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Vegetarianhealth necesitaba un nuevo diseño de logotipo y lanzó un concurso de diseño en 99designs.
Un ganador ha sido elegido entre 139 diseños de 31 diseñadores freelance.
The Vegetarian Health Institute
Our flagship product is The Vegetarian Mastery Program. It's a series of 50 online lessons that teach people to thrive on a vegetarian diet, and not be vulnerable to deficiencies. We also offer custom menu planning, and will sell cooking videos in the future. You can read more here:
Most of our students are adult women. 1/3 are vegetarians. 2/3 are vegans (i.e. they eat no meat, fish, dairy, or eggs). They enroll in our program mostly to learn about nutrition.
For example, how to get enough calcium, iron, protein, and Vitamins A, B12, and D.
But they also learn practical tips, such as how to save money on health food, save time in the kitchen, eat well while traveling, and overcome the social challenges of eating differently.
They have chosen a meat-free diet for a few reasons. (1) Ethical: they don't want to inflict suffering on animals. (2) Health: they want to reduce their risk of high blood pressure, cholesterol, heart disease, or type 2 diabetes. (3) Ecological: they want to reduce their ecological footprint and live a more sustainable lifestyle.
I'd like an icon integrated with our company name. Something original, not reminiscent of generic clip art.
There should probably be green in the logo. Other colors are welcome too. It should represent health, and "thriving". It should have a classy / professional quality. Not cartoon-ish or too informal.
You can leave the word "The" off the beginning of our company name.
It will be used in two ways: (1) at the top of our website and (2) in print materials, such as booklets and PDFs.
If you create a logo out of our initials, then please also spell out our company name to the right of it. (Don't cram it underneath the logo in tiny letters.)
Remember, this will appear at the top of our website.
I am attaching the cover of our Vegetarian Mastery Program because I like the color scheme. Your logo doesn't need to emulate this design, but hopefully, it will complement the design.
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Onderstepoort Journal of Veterinary Research
On-line version ISSN 2219-0635
Print version ISSN 0030-2465
Onderstepoort j. vet. res. vol.78 n.1 Pretoria Jan. 2011
Survey of the livestock ticks of the North West province, South Africa
Arthur M. SpickettI; Ingard H. HeyneI; Roy WilliamsII
IParasites, Vectors and Vector-borne Diseases Programme, ARC-Onderstepoort Veterinary Institute, South Africa
IIVeterinary Geographic Information Systems Programme, ARC-Onderstepoort Veterinary Institute, South Africa
Ticks, as vectors of disease and damage agents, impact directly and indirectly on the economy of the livestock industry in southern Africa. This study surveyed the occurrence and distribution of ticks infesting livestock across the North West province, South Africa. During three phases in consecutive years, officers of the provincial Veterinary Department collected specimens monthly from livestock hosts at specified sites across the province. Data analysis constituted the fourth phase of the study. A total of 1090 collections from 265 sites yielded 42 566 tick specimens, comprising 22 different tick species (18 ixodids, 4 argasids). The specimens represent all of the major tick vectors of disease that occur in South Africa. The major tick-borne diseases (i.e. heartwater, both African and Asiatic bovine babesiosis and anaplasmosis) were found to be prevalent mainly in the north-eastern region of the province, which also displayed the highest tick species diversity. The central region appears transitory to some of the major vectors. Although some tick species were contained within specific regions, others were widespread across the province. Associated serology data show that most herds sampled in areas endemic for babesiosis and anaplasmosis in the north-eastern region are endemically unstable and at risk to these tick-borne diseases should vector control measures become ineffective.
Ixodid ticks are economically of the most important external parasites of livestock in the tropical and sub-tropical parts of the world, including South Africa. Heavy infestation can cause loss of blood, reduce live weight gain rates and lower milk yield, whilst the long-mouthed ticks downgrade the quality of the hides and cause secondary infections (De Castro 1997). They are also recognised worldwide as major vectors of a number of disease-causing pathogens in humans and domestic and game animals, including arboviruses, rickettsiae, spirochaetes and parasitic protozoa. They act as reservoirs and/or multipliers of these organisms and transmit a number of important tick-borne diseases such as heartwater, bovine babesiosis, anaplasmosis and theileriosis. Some ixodid ticks also produce toxins that cause paralysis in sheep (Spickett & Heyne 1988) and sweating sickness in calves (Jongejan & Uilenberg 1994).
Ticks therefore impact both directly (by virtue of heavy infestations) and indirectly (through the transmission of tick-borne diseases) at an economical level as well as in a social context. At the macro-economic level, exports and the commercial production of protein may be affected and at the micro-economic level the subsistence economy of the resource-poor farmer may be at risk. Whilst little actual data exist, it was estimated already some 30 years ago that mortality losses attributed to tick-borne diseases, together with acaricide and vaccine costs, were in the region of R70 million per annum (Van Rensburg 1981), whilst a panel of the Food and Agriculture Organization placed total losses in South Africa at R550 million per annum in 1985. However, these are estimates at best and many resources would have to be harnessed in order to determine more accurate figures regarding the economic impact of ticks. Only one study - on heartwater, which is probably the most important tick-borne disease in South Africa - has been attempted (Minjauw 2005), with total annual losses estimated at R189.6 million.
Paramount to assessing the impact of vectors and disease agents are the identification of the species involved, their distribution and their association with disease. Long-term research since the time of Arnold Theiler in the early 20th century, including the last comprehensive tick survey in South Africa by Gertrud Theiler in 1957 (Theiler 1962), has placed South Africa in the fortunate position of having a wide knowledge of ticks and their associated disease epidemiologies. These findings are documented in wide-ranging publications, with the most important disease-oriented knowledge being condensed into two publications (Coetzer & Tustin 2004; Walker, Keirans & Horak 2000). In the South African context, some 90 ixodid and 25 argasid tick species have been identified. Of these, 35 are normally associated with domestic animals and approximately 15 are considered of economic importance. They transmit, or are associated with, some 23 diseases or health syndromes (Norval & Horak 2004).
In the context of ticks and tick-borne diseases affecting livestock resources, the Directorate of Veterinary Services in the North West province (Department of Agriculture), commissioned a survey to determine tick species presence, their seasonal occurrence, contribution to livestock diseases and distribution across the province.
Materials and methods
Study locality
The survey was conducted over a total area of 116 320 km2 in the North West province of South Africa (between approximately 24º15'S, 22º30'E and 28º15'S, 28º30'E). The area may, according to Acocks (1988), be sectored roughly into three main regions based on vegetation (Figure 1). The north-eastern region consists of bushveld (Mixed, Sour and Sourish-mixed Bushveld, the latter interspersed with Bankenveld and Turf Thornveld). The central region has an equally mixed vegetation, consisting of Dry and Sandy Cymbopogon-Themeda veld with Sourish-mixed Bushveld in its northern reaches. The western, more arid region of the province consists mainly of Kalahari Thornveld.
The climate of the province is characterised by well-defined seasons: hot summers and cool, sunny winters. The climate and rainfall vary from the more mountainous and wetter eastern region to the drier, semi-desert plains of the Kalahari in the west. The rainy season usually falls between October and March. Rainfall is highly variable, with regard to both time and region. On average, the western part of the province receives less than 300 mm rainfall per annum, the central part around 550 mm and the eastern and south-eastern parts receive more than 600 mm.
There are wide seasonal and daily variations in temperature. Summers are very hot (daily average maximum temperatures of 32 ºC in January) and winters are mild to cold (average daily minimum in July is 1 ºC). The far western part is arid, encompassing the eastern portion of the Kalahari Desert. The central part of the province is typically semi-arid, whilst the eastern region is predominantly temperate.
Agriculture is the second most important economic activity. The eastern, wetter region of the province largely supports livestock and crop farming, whilst the central and southern regions are dominated by wheat and maize farming. Livestock and game farming occur in the semi-arid western region of the province. Tourism is considered to have a major growth potential as the province has a rich natural heritage and a network of well-managed, malaria-free national and provincial parks and nature reserves, which boast the 'Big Five'. According to the Department of Agriculture, Forestry and Fisheries (2004) livestock production revolves around the estimated 1.77 million cattle, 729 000 sheep and 753 000 goats in the province. Approximately 43% of cattle, 46% of sheep and 47% of goats are owned by the communal sector. The majority of cattle are found in the north-eastern region (42%), with 34% and 24% being in the central and western regions, respectively. Sheep and goats are farmed predominantly in the western region (44% and 46%, respectively), whilst only to a limited extent in the north-eastern and central regions (sheep: 29% and 27%, respectively; goats: 34% and 20%, respectively). It is this considerable livestock resource that could be adversely affected by ticks and tick-borne diseases.
Survey design and execution
The survey was conducted in four phases over a number of years since 2001. The first three phases included monthly tick collections from identified sites in the north-eastern, central and western regions during three consecutive years (Figure 2).
Collection sites were selected from 1:250 000 charts and subsequently between four and 41 collection sites, depending on spatial distribution, logistics and collectors' time constraints, were assigned to specific areas in each of the three regions (Table 1). Areas considered marginal for specific tick species were included in the selected sites. A total of 114 sites were selected in the north-eastern region (collection phase 1), 116 in the central region (collection phase 2) and 61 in the western region (collection phase 3). As comprehensive coverage as possible of the province was sought to allow for tick distribution mapping. Collection sites were not assigned to the immediate north-east and north-west of Bloemhof (central region) owing to crop farming predominating in these areas.
During each collection phase, nominated animal health technicians from each region received in-house training in basic tick identification, collection and specimen handling before collection commenced at their specified sites. The fourth phase (performed at the Onderstepoort Veterinary Institute [OVI]) involved species identification, database acquisition, distribution mapping using ArcGIS (ESRI) software and reporting.
Ticks were collected off one side of livestock hosts - mainly cattle, goats and sheep - using forceps. Each collection was placed in 70% alcohol in a specimen bottle for dispatch to the OVI for identification and recording. Only one collector, in the Bray area, consistently sampled chicken coops. Owing to prior training collectors were able to perform basic tick species identification in situ, so that as wide a range of species present on the animal could be collected. To gain data on species seasonality, monthly collections from most sites were attempted. Tick collections were, however, disrupted to some extent during the second phase (central region) because of a swine fever outbreak in the Eastern Cape, which required secondment of personnel to assist with containment operations.
In some areas of the north-eastern region, a high incidence of both Rhipicephalus (Boophilus) decoloratus and Rhipicephalus (Boophilus) microplus, the vectors of bovine babesiosis, was evident. A standard immunofluorescent antibody test (Joyner et al. 1972) and a competitive inhibition enzyme-linked immunosorbent assay (Ndung'u et al. 1995; Visser et al. 1992) were used to test blood samples for antibodies to Babesia bovis and Babesia bigemina, and Anaplasma marginale, respectively. Sera collected from 13 properties in the affected areas (from at least 30 cattle per herd, 9-12 months of age) were tested to determine the antibody status of these herds to African and Asiatic babesiosis and anaplasmosis.
Results and discussion
Number of ticks, species composition and collections
A total of 42 566 ticks (from 1190 collections across 265 collection sites) were received for identification. The breakdown of collections is as follows:
(1) north-eastern region: 21 045 specimens from 429 collections
(2) central region: 10 391 specimens from 398 collections
(3) western region: 11 130 from 363 collections.
Owing to the collection method employed almost all the ticks received were adults (97.9%), with roughly equal numbers of males and females. The immatures (nymphs = 1.8%; larvae = 0.3%), mostly Rhipicephalus evertsi evertsi and four nymphs of Otobius megnini, were collected more by chance than intention from the ears of cattle.
Altogether 22 tick species were identified (18 from six Ixodidae genera; four from three Argasidae genera). The main tick species were all hard ticks (Ixodidae) and included R. evertsi evertsi (31.5%), Hyalomma rufipes (22.4%), Amblyomma hebraeum (17.3%), R. (B.) decoloratus (12.5%), Rhipicephalus appendiculatus (11.2%), Hyalomma truncatum (2.3%), R. (B.) microplus (1.6%), Rhipicephalus evertsi mimeticus (0.5%) and Rhipicephalus simus (0.21%). Other ticks of lesser importance or those collected in low numbers or during only a few collections, as well as the Argasidae collections, are as shown in Table 2.
Monthly collections over a period of 10-12 months were received from 70 collection sites, which allowed the seasonal occurrence of the major tick vectors to be determined. Monthly collections from a further 175 collection sites were received over a period varying from 1 to 9 months.
Tick species distribution and seasonality
The distribution patterns and seasonality of the major tick species collected are described below.
Amblyomma hebraeum
According to Norval and Horak (2004), Amblyomma hebraeum is present in grassed bushveld and wooded savanna regions. In the present survey, A. hebraeum accounted for 17.3% of the collected ticks and appears well established in the Mixed and Sourish-mixed Bushveld areas of the North West province (Figure 3). It is present mainly in the north-eastern and northern portion (Mixed Bushveld) of the central region, with singular intrusions into the Kalahari Thornveld south-east of Vryburg and west of Mafikeng. The latter distribution appears to be established populations because they were consistently collected during the summer months at these sites.
Adult ticks prefer large hosts such as cattle and large wild ruminants, but also infest sheep and goats (Horak et al. 1987; Walker et al. 2003). In this survey 90.8% of A. hebraeum specimens were recovered from cattle, 4.9% from goats and 3.3% from sheep (1.0% were not stipulated). The adults of this species were present throughout the year, with a high incidence in both the north-eastern and central regions during November and December (summer), similar to observations by Rechav (1982) for the Eastern Cape. Higher numbers of adults were found in the central region between March and May (autumn) than in the north-eastern region during these months.
Hyalomma rufipes
H. rufipes (previously the subspecies Hyalomma marginatum rufipes [Apanaskevich & Horak 2008]) is a vector of the Crimean-Congo haemorrhagic fever virus. It is the most widely distributed species of this tick genus in South Africa, occurring in the greater part of the country (Norval & Horak 2004). It was found distributed widely over the whole of the North West province, with it being absent from only eight of the collection sites (Figure 4). The life cycle may be completed in one year and peak numbers of adults were evident in the summer months (November-February).
H. rufipes accounted for 22.4% of the total number of specimens collected in this survey. Of these, 97.2% were from cattle, 1.5% from sheep and 0.5% were found on goats (0.8% were not assigned a host).
Hyalomma truncatum
H. truncatum is widely distributed over the whole of the North West province (Figure 5) and was present in all the ecological zones sampled. Of the adult H. truncatum specimens collected, 89.9% were from cattle, 0.8% from sheep and 8.5% from goats; 0.8% were not assigned a host. H. truncatum accounted for only 2.3% of the total number of specimens collected. Some strains of this species transmit a toxin that causes an epitheliotrophic condition called sweating sickness, which affects young calves in particular (Neitz 1959). The tendency for adults to attach preferentially in the tail switch of cattle (where it is easily overlooked during sampling) may explain why this tick was not collected at more of the collection sites. Its seasonal occurrence in the North West province confirms its annual life cycle, with adults reaching peak numbers between January and March.
Rhipicephalus appendiculatus
R. appendiculatus is restricted to the higher-rainfall, eastern regions of South Africa (Walker et al. 2000) and according to Theiler (1962) does not occur in open grassland without bush; it prefers tall grass interspersed with trees. Accordingly, this species was found well established in the north-eastern region of the province and in the bushveld areas of the northern reaches of the central region around Mafikeng (Figure 6). The remainder of the province, especially the western region, appears to be ecologically unsuited to the establishment of this tick species.
This species accounted for 11.2% of the specimens collected. Of the total number of adults collected, 86.9% were from cattle, 7.4% from goats and 5.0% from sheep; the remaining 0.7% were not assigned a host. Adult activity commenced only during the summer months (between December and March), as reported for the Eastern Cape by Rechav (1982).
Rhipicephalus (Boophilus) decoloratus
The ticks we have chosen to name R. (B.) decoloratus and R. (B.) microplus were originally known as Boophilus decoloratus and Boophilus microplus, respectively. However, based on molecular evidence (Beati & Keirans 2001; Murrell, Campbell & Barker 2000), they were included in a 2002 world list of valid tick names as R. (B.) decoloratus and R. (B.) microplus (Horak, Camicas & Keirans 2002). Guglielmone et al. (2010) have subsequently omitted the subgenus and these ticks appear in their list of valid tick names as R. decoloratus and R. microplus. We chose to include the subgenus in our nomenclature.
R. (B.) decoloratus represented 12.5% of the collections in this survey, with 98.1% of specimens being collected from cattle, only 0.5% from sheep and 0.3% from goats. The remaining 1.1% were not assigned hosts. This distribution confirms its host preference for large ungulates (Mason & Norval 1980). The species normally occurs in temperate savanna regions, typically in grass- and woodland areas used by cattle, and tends to be absent in drier areas (Walker et al. 2003). It is well established in the grassed Bushveld biomes (especially the Sourish-mixed Bushveld) of the north-eastern region and northern reaches of the central region of the North West province, around Rustenburg, Zeerust, Mafikeng and Potchefstroom (Figure 7). The tick also inhabits seemingly suitable habitats (probably created by irrigated land use) in the Cymbopogon-Themeda veld near Bloemhof and the Kalahari Thornveld near Kudumane and Vryburg in the western region. Apparently, suitably high temperatures - well above the developmental threshold of 10 ºC (Spickett & Heyne 1990) - and host availability yielded high numbers of this one-host species, even during the winter months. Peak numbers were evident in December and January and again from March to July. Since R. (B.) decoloratus is a vector of B. bigemina, African babesiosis may therefore be a threat throughout the year.
Rhipicephalus (Boophilus) microplus
R. (B.) microplus, as R. (B.) decoloratus, inhabits savanna climatic regions in wooded grasslands used as cattle pasture (Walker et al. 2003). R. (B.) microplus (Figure 8) was found to have a more limited distribution compared to that of R. (B.) decoloratus, being confined to the Sourish-mixed Bushveld of the north-eastern region (around Rustenburg, north-east of Potchefstroom and north of Zeerust). The species was also found in an isolated pocket near Bloemhof, probably introduced by cattle and finding suitable habitats here.
Cattle are considered the only effective hosts of R. (B.) microplus (Mason & Norval 1980), to the extent that this species is absent in game parks, where no cattle occur (Horak et al. 1986). Recently, goats have been implicated as alternate hosts for this species, but in the presence of cattle in order to maintain populations (Nyangiwe & Horak 2007). In the present survey 81.8% of R. (B.) microplus specimens were collected from cattle and, significantly, a relatively high 7.7% were found on goats. None were found on sheep. The remaining 10.5% of the collected R. (B.) microplus specimens were not assigned a host by the collectors, but were most probably collected off cattle.
The seasonality of R. (B.) microplus was similar to that of R. (B.) decoloratus, with peak numbers occurring during the autumn months of April and May.
Rhipicephalus evertsi evertsi
R. evertsi evertsi is widely distributed and common on livestock throughout much of Africa, occurring in desert, steppe, savanna and temperate climatic regions (Walker et al. 2003). It has the most widespread distribution of species in the genus Rhipicephalus in Africa and has an extensive host range (Walker et al. 2000). It was the most commonly collected species in the North West province (31.5% of all specimens), being distributed over the whole province and absent at only two collection sites (Figure 9). In this survey, the adults that were collected came from cattle (79.1%), goats (15.9%) and sheep (3.9%), whilst the remaining 1.1% were unaccounted for as to host. Peak activity was recorded early in autumn (May), although high numbers were also recorded during the summer months.
Rhipicephalus evertsi mimeticus
Although of minimal economic importance, this species is interesting in that it is recorded as occurring in the arid regions of Angola, Namibia and Botswana (Theiler 1962). With regard to morphology and biology it is very similar to its subspecies R. evertsi evertsi and can also cause paralysis in sheep, mainly lambs, owing to secreting a toxin in the saliva whilst feeding (Gothe 1999).
This species has infiltrated the North West province, with suitable habitat conditions enabling it to establish populations in the western region (Figure 10), possibly by means of sheep introduced from Botswana or Namibia, and thus likely displacing R. evertsi evertsi at these localities. Recurring monthly collections of relatively high numbers off sheep from these sites confirmed the establishment of viable R. evertsi mimeticus populations. Being subspecies, R. evertsi mimeticus and R. evertsi evertsi should interbreed, yet both were found to be morphologically distinct and could easily be distinguished taxonomically at the same localities, which may indicate some degree of speciation. This observation needs further investigation.
Rhipicephalus simus
This species establishes in regions with a savanna climate and is never encountered in high numbers (Norval & Mason 1981; Walker et al. 2000). It is well established in the bushveld areas of the north-eastern region of the province to which its distribution is confined (Figure 11). Of the R. simus collected, 71.9% were from cattle, 4.0% from sheep and 18.5% from goats. This species was also recovered from dogs (4.0%), whilst 1.6% were not assigned a host by collectors.
Tick-borne disease serology
As shown in Figures 7 and 8, R. (B.) decoloratus and R. (B.) microplus occurred sympatrically at some localities in the north-eastern region of the province. Both species are associated with the transmission of the causative organism of anaplasmosis (Ana. marginale) as well as the organisms causing bovine babesiosis (Babesia bigemina and Babesia bovis) (De Vos & Potgieter 1994). The antibody status of cattle herds to these tick-borne pathogens in the areas of sympatric distribution of these two tick vector species, as well as the presence (or absence) of the two tick vector species is shown in Table 3.
The results indicate that only one property (Commiesiedrift) is in a state of endemic stability (Norval et al. 1983) to B. bigemina (100%), whereby sufficient infected vector ticks (R. [B.] decoloratus) are present to transmit the pathogen such that all the animals show an antibody response indicative of disease immunity. All other properties appear to experience endemic instability to both B. bigemina and B. bovis, strongly suggesting that intensive chemical control is practiced on these properties, thereby reducing vector challenge and, subsequently, pathogen transmission. On the endemically unstable properties, more than 40% of the cattle show no antibodies to the causative organisms and are thus fully susceptible and at risk to babesiosis should they be challenged by infected ticks.
None of the animals on six properties showed antibodies to B. bigemina despite the presence of the tick vector, possibly owing to uninfected ticks (unlikely) or extremely stringent tick control practices. These animals could be completely susceptible to bovine babesiosis should they be challenged by infected ticks. R. (B.) microplus was absent on five of these properties and, as expected, none of the animals tested positive for B. bovis antibodies. However, on one of the properties (Leeukraal) on which no animals tested positive for B. bigemina in the presence of the tick vector, 50% of the animals tested positive for B. bovis in the presence of the vector tick. The latter case is difficult to explain: it is possibile that R. (B.) microplus, as a vector, presented a much higher challenge than did R. (B.) decoloratus and that antibody manifestation to B. bigemina was subsequently lost. On two properties, respectively 28% and 40% of the animals showed antibody titres to B. bovis, indicative of R. (B.) microplus infestation, although this vector tick was not collected at the time of the survey.
This study was conducted to survey the occurrence and distribution of ticks infesting livestock in the North West province of South Africa. The survey entailed the monthly collection of tick specimens from livestock hosts at specified sites in the north-eastern, central and western regions of the province. Tick specimens were subsequently identified and the distributions of the major species plotted.
According to this survey, livestock in this province harbour 22 tick species (18 ixodids; 4 argasids). The major tick-borne diseases were prevalent mainly in the north-eastern region, which also displayed the highest tick species diversity.
The vectors of Corridor disease (buffalo-associated Theileria parva), namely R. appendiculatus and Rhipicephalus zambeziensis were present in the north-eastern region of the province, which indicates that care should be exercised in the introduction of Corridor-infected buffalo in these regions. The central region appears transitory to the major vectors A. hebraeum and R. (B.) decoloratus, whilst the two Hyalomma vectors of Crimean-Congo haemorrhagic fever virus are widespread over the whole province. The north-western area (Bray) of the western region has been infiltrated with R. evertsi mimeticus, a species considered to be non-endemic to South Africa. Most herds sampled for serology in areas endemic for babesiosis and anaplasmosis in the north-eastern region are endemically unstable and at risk to these tick-borne diseases should vector control measures become ineffective.
This study was funded by the Directorate of Veterinary Services of the North West province (Department of Agriculture). We wish to thank the Directorate for their wholehearted and unstinting support for this survey, at managerial and operational level. Special thanks go to the many officers directly involved in the collections.
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Ndung'u, L.W., Aguirre, C., Rurangirwa, F.R., McElwain, T.F., McGuire, T.C., Knowles, D.P. et al., 1995, 'Detection of Anaplasma ovis infection in goats by major surface protein 5 competitive inhibition enzyme-linked immunosorbent assay', Journal of Clinical Microbiology 33, 675-679. [ Links ]
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Norval, R.A.I. & Mason, C.A., 1981, 'The ticks of Zimbabwe. II. The life cycle, distribution and hosts of Rhipicephalus simus Koch, 1844', Zimbabwe Veterinary Journal 12, 2-9. [ Links ]
Norval, R.A.I. & Horak, I.G., 2004, 'Vectors: Ticks', in J.A.W. Coetzer & R.C. Tustin (eds.), Infectious diseases of livestock, 2nd edn., pp. 3-42, Oxford University Press, Cape Town. [ Links ]
Norval, R.A.I., Fivaz, B.H., Lawrence, J.A. & Daillecourt, T., 1983, 'Epidemiology of tick-borne diseases of cattle in Zimbabwe. I. Babesiosis', Tropical Animal Health and Production 15, 87-94. doi:10.1007/BF02239802, PMid:6868134 [ Links ]
Nyangiwe, N. & Horak, I.G., 2007, 'Goats as alternative hosts of cattle ticks', Onderstepoort Journal of Veterinary Research 74, 1-7. PMid:17708147 [ Links ]
Rechav, Y., 1982, 'Dynamics of tick populations (Acari: Ixodidae) in the eastern Cape Province of South Africa', Journal of Medical Entomology 19, 679-700. PMid:7154025 [ Links ]
Spickett, A.M. & Heyne, H., 1988, 'A survey of Karoo tick paralysis in South Africa', Onderstepoort Journal of Veterinary Research 55, 89-92. PMid:3393373 [ Links ]
Spickett, A.M. & Heyne, H., 1990, 'The prehatch period and larval survival of Boophilus decoloratus (Koch, 1844) (Acarina, Ixodidae) under natural conditions in the Transvaal, South Africa', Onderstepoort Journal of Veterinary Research 57, 95-98. PMid:2339003 [ Links ]
Theiler, G., 1962, 'The ixodoidea parasites of vertebrates in Africa south of the Sahara (Ethiopian Region), Project S 9958', Report to the Director of Veterinary Services, Onderstepoort. [ Links ]
Van Rensburg, S.J.J., 1981, 'The importance and need for tick control - what it means to the industry', in G.B. Whitehead & J.D. Gibson (eds.), Tick biology and control: International conference proceedings, Grahamstown, South Africa, January 27-29, 1981, pp. 119-122. [ Links ]
Visser, E.S., McGuire, T.C., Palmer, G.H., Davis, W.C., Shkap, V., Pipano, E. et al., 1992, 'The Anaplasma marginale msp5 gene encodes a 19-kilodalton protein conserved in all recognized Anaplasma species', Infection and Immunity 60, 5139-5144. PMid:1280624, PMCid:258289 [ Links ]
Walker, A.R., Bouattour, J.-L., Camicas, A., Estrada-Pena, I.G., Horak, I.G., Latif, A.A. et al., 2003, Ticks of domestic animals in Africa: a guide to identification of species, Bioscience reports, Edinburgh. [ Links ]
Walker, J.B., Keirans, J.E. & Horak, I.G., 2000, The genus Rhipicephalus (Acari, Ixodidae): a guide to the brown ticks of the world, Cambridge University Press, Cambridge. [ Links ]
Correspondence to:
Arthur Spickett
Postal address: Private Bag X05
Onderstepoort 0110, South Africa
Email: email@example.com
Received: 12 Nov. 2010
Accepted: 12 Jan. 2011
Published: 14 Sept. 2011
© 2011. The Authors. Licensee: OpenJournals Publishing. This work is licensed under the Creative Commons Attribution License.

subset: commoncrawl


text:
Sunglasses or sun glasses are a form of protective eyewear designed primarily to prevent bright sunlight and high-energy visible light from damaging or discomforting the eyes. They can sometimes also function as a visual aid, as variously termed spectacles or glasses exist, featuring lenses that are colored, polarized or darkened. In the early 20th century they were also known as sun cheaters (cheaters being an American slang term for glasses).[1]
Most people find direct sunlight too bright for comfort during outdoor activities. Healthcare professionals recommend eye protection whenever the sun comes outbeach.
In prehistoric and historic time, Inuit peoples wore flattened walrus ivory "glasses," looking through narrow slits to block harmful reflected rays of the sun.[3]
It is said that the Roman emperor [5]
James Ayscough began experimenting with tinted lenses in spectacles in the mid-18th century, around 1752. These were not "sunglasses" as that term is now used; Ayscough believed blue- or green-tinted glass could correct for specific vision impairments. Protection from the Sun's rays was not a concern for him.
Yellow/amber and brown-tinted spectacles were also a commonly prescribed item for people with syphilis in the 19th[dubious ] and early 20th centuries because sensitivity to light was one of the symptoms of the disease.
Modern developments
In the early 1900s, the use of sunglasses started to become more widespread, especially among stars of movies. It is commonly believed that this was to avoid recognition by fans, but an alternative reason sometimes given is that they often had red eyes from the powerful [6]
Polaroid filter.
Visual clarity and comfort
Sunglasses can improve visual comfort and visual clarity by protecting the eye from glare.[7]
Various types of disposable sunglasses are dispensed to patients after receiving eye examinations.
The lenses of polarized sunglasses reduce glare reflected at some angles off shiny non-metallic surfaces such as water. They are popular among fishermen because they allow wearers to see into water when normally only glare would be seen.
The glare is neutralized by blocking the vertical (magnetic) components of light.
Sunglasses offer protection against excessive exposure to light, including its visible and invisible components.
The most widespread protection is against ultraviolet radiation, which can cause short-term and long-term ocular problems such as solar eclipse.
More recently, [12] Sunglasses are especially important for children, as their ocular lenses are thought to transmit far more HEV light than adults (lenses "yellow" with age).
There has been some speculation that sunglasses actually promote skin cancer.[13] This is due to the eyes being tricked into producing less melanocyte-stimulating hormone in the body.
Assessing the protection of sunglasses
The only way to assess the protection of sunglasses is to have the lenses measured, either by the manufacturer or by a properly equipped optician. Several standards for sunglasses (see below) allow a general classification of the UV protection (but not the blue light protection), and manufacturers often indicate simply that the sunglasses meet the requirements of a specific standard rather than publish the exact figures.
The only "visible" quality test for sunglasses is their fit. The lenses should fit close enough to the face that only very little "stray light" can reach the eye from their sides, or from above or below, but not so close that the eyelashes smear the lenses. To protect against "stray light" from the sides, the lenses should fit close enough to the temples and/or merge into broad temple arms or leather blinders.
It is not possible to "see" the protection that sunglasses offer. Dark lenses do not automatically filter out more harmful UV radiation and blue light as compared to light lenses. Inadequate dark lenses are even more harmful than inadequate light lenses (or wearing no sunglasses at all) because they provoke the pupil to open wider. As result, more unfiltered radiation enters the eye. Depending on the manufacturing technology, sufficiently protective lenses can block much or little light, resulting in dark or light lenses. The lens color is not a guarantee either. Lenses of various colors can offer sufficient (or insufficient) UV protection. Regarding blue light, the color gives at least a first indication: Blue blocking lenses are commonly yellow or brown whereas blue or gray lenses cannot offer the necessary blue light protection. However, not every yellow or brown lens blocks sufficient blue light. In rare cases, lenses can filter out too much blue light (i.e., 100%), which affects color vision and can be dangerous in traffic when colored signals are not properly recognized.
High prices cannot guarantee sufficient protection as no correlation between high prices and increased UV protection has been demonstrated. A 1995 study reported that "Expensive brands and polarizing sunglasses do not guarantee optimal UVA protection."[16]
Further functions of sunglasses
While non-tinted glasses are very rarely worn without the practical purpose of correcting eyesight or protecting one's eyes, sunglasses have become popular for several further reasons, and are sometimes worn even indoors or at night.
Sunglasses can be worn to hide one's eyes. They can make tells which involve eye movement and thus gain an advantage.
Fashion trends can be another reason for wearing sunglasses, particularly designer sunglasses. Sunglasses of particular shapes may be in vogue as a fashion accessory. Fashion trends can also draw on the "cool" image of sunglasses.
People may also wear sunglasses to hide an abnormal appearance of their eyes. This can be true for people with severe visual impairment, such as the nystagmus).
Some lawbreakers have also been known to wear sunglasses during or after committing a crime as an aid to hiding their identities.[17]
Standards for sunglasses
There are three major sunglass standards, which are popularly known mostly as a reference for sunglass protection from UV radiation; the standards do, however, also include further requirements. A worldwide ISO standard does not yet exist, but by 2004, attempts to introduce such standard have led to a respective ISO standards committee, subcommittee, technical committee, and several working groups.[18] Sunglasses sold in the United States are regulated by the Food and Drug Administration and are required to conform to safety standards.
The Australian Standard is AS/NZS 1067:2003 Sunglasses and fashion spectacles. The five ratings for transmittance (filter) under this standard are based on the amount of absorbed light, 0 to 4, with "0" providing some protection from UV radiation and sunglare, and "4" indicating a high level of protection, but not to be worn when driving. Australia introduced the world's first national standards for sunglasses in 1971. They were subsequently updated and expanded, leading in 1990 to AS 1067.1-1990 Sunglasses and fashion spectacles (incl. Part 1 Safety Requirements and Part 2 Performance Requirements), which was superseded in part in 2003 by AS/NZS 1067:2003 Sunglasses and fashion spectacles. The 2003 update made the Australian standard relatively similar to the European standard. This step opened the European market to Australian-made sunglasses, but the standard also maintained requirements considered specific to Australia's climate.[19]
The European standard EN 1836:2005 has four transmittance ratings: "0" for insufficient UV protection, "2" for sufficient UHV protection, "6" for good UHV protection and "7" for "full" UHVV protection, meaning that no more than 5% of the 380 nm rays are transmitted. Products which fulfill the standard receive a CE mark. There is no rating for transmittance protection for radiation of up to 400 nm ("UV400"), as required in other countries (incl. the United States) and recommended by experts.[9] The current standard EN 1836:2005 was preceded by the older standards EN 166:1995 (Personal eye protection –Specifications), EN167: 1995 (Personal eye protection – Optical test methods), and EN168: 1995 (Personal eye protection – Non-optical test methods), which in 2002 were republished as a revised standard under the name of EN 1836:1997 (which included two amendments). In addition to filtering, the standard also lists requirements for minimum robustness, labeling, materials (non-toxic for skin contact and not combustible) and lack of protrusions (to avoid harm when wearing them).[18]
The U.S. standard is [20]
Special-use sunglasses
Sunglasses in sports
As do corrective glasses, sunglasses have to meet special requirements when worn for sports. They need shatterproof and impact-resistant lenses; a strap or other fixing is typically used to keep glasses in place during sporting activities, and they have a nose cushion.
For water sports, so-called water sunglasses (also: surf water skiing.
Mountain climbing or traveling across glaciers or snowfields requires above-average eye protection, because sunlight (including ultraviolet radiation) is more intense in higher altitudes, and snow and ice reflect additional light. Popular glasses for this use are a type called glacier glasses or glacier goggles. They typically have very dark round lenses and leather blinders at the sides, which protect the eyes by blocking the Sun's rays around the edges of the lenses.
Sunglasses in space
Special protection is required for space travel because the sunlight is far more intense and harmful than on Earth, where it is always filtered through the [21]
The first sunglasses used in a Moon landing were the original [21]
1969 on board the Buzz Aldrin stows his sunglasses before the Moon landing
1969: Helmet visor protecting Aldrin's eyes on the Moon
The color distortion, which could affect safety when, for instance, driving a car or a school bus.
- Gray and green lenses are considered neutral because they maintain true colors.
- Brown lenses cause some color distortion, but also increase contrast.
- Turquoise lenses are good for medium and high light conditions, because they are good at enhancing contrast, but do not cause significant color distortion.
- Orange and yellow lenses increase both contrast and depth perception. They also increase color distortion. Yellow lenses are used by pilots, boaters, fishers, shooters, and hunters for their contrast enhancement and width perception properties.[11]
- Blue or purple lenses are mainly cosmetic.
With the introduction of citation needed]
While some blue blocking sunglasses (see citation needed]
Some models have polarized lenses, made of diffuse sky radiation (skylight). This can be especially useful when fishing, for which the ability to see beneath the surface of the water is crucial.
A mirrorshades. A mirror coating does not get hot in sunlight and it prevents scattering of rays in the lens bulk.
Sunglass lenses are made of either glass, plastic, or SR-91. Plastic lenses are typically made from acrylic, polycarbonate, CR-39 or polyurethane. Glass lenses have the best optical clarity and scratch resistance, but are heavier than plastic lenses. They can also shatter or break on impact. Plastic lenses are lighter and shatter-resistant, but are more prone to scratching. Polycarbonate plastic lenses are the lightest, and are also almost shatterproof, making them good for impact protection. CR-39 is the most common plastic lens, due to low weight, high scratch resistance, and low transparency for ultraviolet and infrared radiation. SR-91 is a proprietary material that was introduced by Kaenon Polarized in 2001. Kaenon's lens formulation was the first non-polycarbonate material to pass the high-mass impact ANSI Z.87.1 testing.[26] Additionally, it was the first to combine this passing score with the highest marks for lens clarity. Jerry Garcia's sunglasses had a polykrypton-C type of lens which was 'cutting edge' in 1995.
Any of the above features, color, polarization, gradation, mirroring, and materials, can be combined into the lens for a pair of sunglasses. Gradient glasses are darker at the top of the lens where the sky is viewed and transparent at the bottom. Photochromic lenses gradually darken when exposed to ultraviolet light.
Frames are generally made of plastic, Oakley, for example, has straight resting hooks on all their glasses, preferring to call them "earstems".
Frames can be made to hold the lenses in several different ways. There are three common styles: full frame, half frame, and frameless. Full frame glasses have the frame go all around the lenses. Half frames go around only half the lens; typically the frames attach to the top of the lenses and on the side near the top. Frameless glasses have no frame around the lenses and the ear stems are attached directly to the lenses. There are two styles of frameless glasses: those that have a piece of frame material connecting the two lenses, and those that are a single lens with ear stems on each side.
Some sports-optimized sunglasses have interchangeable lens options. Lenses can be easily removed and swapped for a different lens, usually of a different color. The purpose is to allow the wearer to easily change lenses when light conditions or activities change. The reasons are that the cost of a set of lenses is less than the cost of a separate pair of glasses, and carrying extra lenses is less bulky than carrying multiple pairs of glasses. It also allows easy replacement of a set of lenses if they are damaged. The most common type of sunglasses with interchangeable lenses has a single lens or shield that covers both eyes. Styles that use two lenses also exist, but are less common.
Nose bridge
Nose bridges provide support between the lens and the face. They also prevent pressure marks caused by the weight of the lens or frame on the cheeks. People with large noses may need a low nose bridge on their sunglasses. People with medium noses may need a low or medium nose bridge. People with small noses may need sunglasses with high nose bridges to allow clearance.
Fashion (alphabetically)
Aviator sunglasses
Aviator sunglasses feature oversize teardrop-shaped lenses and a thin metal frame. The design was introduced in 1936 by Bausch & Lomb for issue to U.S. military aviators. As a fashion statement, aviator sunglasses are often made in mirrored, colored, and wrap-around styles.
In addition to pilots, Aviator-style sunglasses gained popularity with young people in the late 1960s and continue to be popular, with only a brief fall in demand during the 1990s.
Clip-on glasses
Clip-on glasses are a form of tinted glasses that can be clipped on to eyeglasses for protection from the Sun. The best protection is polarized lens with 1.1mm. An alternative are flip-up glasses.
Gradient lenses
Gradient lenses go from a darker shade at the top to a lighter one at the bottom, so there will be more protection from sunlight the higher one looks through the lens, but the lower one looks through the lens, the less protection is offered. An advantage is that one can wear them indoors without fear of tripping over something and also allowing the user to see. Wearing sunglasses to nightclubs has become common in recent times, where the gradient lens comes in handy. Gradient lenses may also be advantageous for activities such as flying airplanes and driving automobiles, as they allow the operator a clear view of the instrument panel, low in his line of sight and usually hidden in shadow, while still reducing glare from the view out the windscreen. The Independent (London), has also referred to these style of sunglasses as the Murphy Lens.[27]
Double gradient lenses are dark at the top, light in the middle and dark at the bottom.
Gradients should not be confused with progressive lenses.
Flip-up sunglasses
Flip-up sunglasses add the benefits of sunglasses to corrective eyeglasses, allowing the wearer to flip up the tinted lenses for indoor use. An alternative are clip-on glasses.
Mirrored sunglasses
Mirrored lenses, having a metallic, partially reflective coating on the outer surface, combined with a tinted glass lens, are an alternative to polarization for UV protection, improving contrast when depth perception is important such as seeing moguls and ice while skiing or snowboarding. The mirrored lens reflects glare to protect the eyes, but improves the ability to see contrasts, and mirrored lenses of different colors can expand the range of fashion styles.
Oversized sunglasses
Oversized sunglasses, which were fashionable in the 1980s, are now often used for humorous purposes. They usually come in bright colors with colored lenses and can be purchased cheaply.
The singer Elton John sometimes wore oversized sunglasses on stage in the mid-1970s as part of his Captain Fantastic act.
In the early twenty-first century moderately oversized sunglasses have become a fashion trend. There are many variations, such as the "Onassis", discussed below, and Dior white sunglasses.
Onassis glasses or "Jackie O's" are very large sunglasses worn by women. This style of sunglasses is said to mimic the kind most famously worn by Jacqueline Kennedy Onassis in the 1960s. The glasses continue to be popular with women, and celebrities may use them, ostensibly to hide from paparazzi.
Oversized sunglasses, because of their larger frames and lenses, are useful for individuals who are trying to minimize the apparent size or arch of their nose.[28] Oversized sunglasses also offer more protection from sunburn due to the larger areas of skin they cover, although sunblock should still be used.
Shutter Shades
Shutter Shades were a fad in the early 1980s. Instead of tinted lenses, they decrease sun exposure by means of a set of parallel, horizontal shutters (like a small window shutter). Analogous to Inuit goggles (see above), the principle is not to filter light, but to decrease the amount of sun rays falling into the wearer's eyes. To provide UV protection, Shutter Shades sometimes use lenses in addition to the shutters; if not, they provide very insufficient protection against ultraviolet radiation and blue light.
"Teashades" (sometimes also called "John Lennon glasses", "Round Metal", or, occasionally, "Granny Glasses") were a type of psychedelic art wire-rim sunglasses that were often worn, usually for purely aesthetic reasons, by members of the 1960s counterculture, as well as by opponents of segregation.[citation needed] Pop icons such as Mick Jagger, Roger Daltrey, John Lennon, Jerry Garcia, Boy George, Liam Gallagher and Ozzy Osbourne, all wore teashades. The original teashade design was made up of medium-sized, perfectly round lenses, supported by pads on the bridge of the nose and a thin wire frame. When teashades became popular in the late 1960s, they were often elaborated: Lenses were elaborately colored, mirrored, and produced in excessively large sizes, and with the wire earpieces exaggerated. A uniquely colored or darkened glass lens was usually preferred. Modern versions tend to have plastic lenses, as do many other sunglasses. Teashades are hard to find in shops today; however, they can still be found at many costume Web sites and in some countries.
The term has now fallen into disuse, although references can still be found in literature of the time. "Teashades" was also used to describe glasses worn to hide the effects of marijuana (conjunctival injection) or bloodshot eyes or the effects of opiates such as heroin (pupillary constriction).
The glasses worn by Lady Gaga have been seen wearing several variations of teashades. Howard Stern was also known for wearing teashades in the early to mid 90's and never taking them off in public. Unlike the others, Jerry Garcia actually created his own line of sunglasses in his name just before he passed away.
The Ray-Ban Wayfarer is a plastic-framed design for sunglasses produced by the Ray-Ban company. Introduced in 1952, the trapezoidal lenses are wider at the top than the bottom and were famously worn by James Dean, Roy Orbison and other actors and singers. The original frames were black; frames in many different colors were later introduced. There is always a silver piece on the corners as well.
Wrap-around sunglasses
Wrap-arounds (sometimes also called "Yoko Ono glasses") are a specific design of sunglasses. They are characterized by a single, smooth, semi-circular lens that covers both eyes and much of the same area of the face covered by protective goggles. The lens is usually combined with a minimal plastic frame and single piece of plastic serving as a nosepiece. As an alternative, the glasses can have two lenses, but the design evokes the same semicircle.
Other names for sunglasses
|This section does not references or sources. (January 2010)
There are various words referring to eyepieces with darkened lenses:
- Shades is probably the most widely used term for sunglasses in North America.
- Glares is a term popular in India if the glass is dark.
- Glints is a term for glasses originating from the "glint" that is noticeable when somebody wearing glasses moves their head.
- Sun spectacles is a term used by some opticians.
- Spekkies is a term used predominantly in southern Australia.
- Sun specs (also sunspecs) is the shortened form of sun spectacles.
- Sunglass a monocle version.[citation needed]
- Sun-shades can also refer to the sun-shading eyepiece-type, although the term is not exclusive to these. Also in use is the derivative abbreviation, shades.
- Dark glasses (also preceded by pair of) — generic term in common usage.
- Sunnies is Australian, South African, UK and New Zealand slang
- Smoked spectacles usually refers to the darkened eyepieces worn by blind people.
- Solar shields Usually refers to models of sunglasses with large lenses.
- Stunna shades Used as a slang term in the hyphy movement, usually referring to sunglasses with oversized lenses.
- Glecks is Scottish slang for glasses or sunglasses.
- Cooling glasses is a term used in Southern India (predominantly Kerala) and the Middle East for sunglasses.
Major brands
- Oakley, Inc.
- Ray-Ban
- Kaenon Polarized
- Maui Jim
- Costa Del Mar
- Persol
- Serengeti
- Luxottica
- ic! berlin
- Randolph Engineering, Inc.
See also
- ^ Partridge, Eric (2006). The New Partridge Dictionary of Slang and Unconventional English. Tom Dalzell, Terry Victor. Routledge. p. 377.
- ^ Ellis, Rachel (2010-06-01). "How making your child wear sunglasses could save their sight". Eye Care Trust Organization UK. Daily Mail. http://www.dailymail.co.uk/health/article-1282980/How-making-child-wear-sunglasses-save-sight.html. Retrieved 2010-10-19.
- ^ "Prehistoric Inuit Snow-Goggles, circa 1200". Canadian Museum of Civilization. 1997-10-03. http://collections.civilisations.ca/public/pages/cmccpublic/alt-emupublic/Display.php?irn=855927. Retrieved 2009-01-25.
Acton, Johnny; Adams, Tania; Packer, Matt (2006). Jo Swinnerton. ed. Origin of Everyday Things. 1-4027-4302-5.
- ^ "Pliny the Elder, The Natural History, Book XXXVII, Ch. 16". Perseus.tufts.edu. http://www.perseus.tufts.edu/cgi-bin/ptext?lookup=Plin.+Nat.+37.16. Retrieved 2010-05-13.
- ^ Ament, Phil (2006-12-04). "Sunglasses History – The Invention of Sunglasses". The Great Idea Finder. Vaunt Design Group. http://www.ideafinder.com/history/inventions/sunglasses.htm. Retrieved 2007-06-28.
- ^ "The History Of Sunglasses". http://www.articlesurfing.com/arts_and_crafts/the_history_of_sunglasses.html. Retrieved 2012-05-01.
- ^ Sakamoto Y., Sasaki K., Kojima M., Sasaki H., Sakamoto A., Sakai M., Tatami A. "The effects of protective eyewear on hair and crystalline lens transparency. Dev Ophthalmol. 2002;35:93-103. PMID 12061282.
- ^ http://www.cancer.org.au/File/PolicyPublications/PSeye%20protectionAUG06.pdf. Retrieved 2010-05-13.
- ^ Karlsruhe (retrieved 21 September 2009)
Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Eine dringende Aufgabe und ihre Lösung. Teil 1: Beschaffenheit des Lichts, innere und äußere Abwehrmechanismen. [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution]. Zeitschrift für praktische Augenheilkunde, 29, pp. 111-116.
Siegfried Hünig (2008). Optimierter Lichtschutz der Augen. Teil 2: Sehprozess als Risikofaktor, Lichtschutz durch Brillen [Optimized protection from light-inflicted eye damage. A pressing problem and a simple solution]. Zeitschrift für praktische Augenheilkunde, 29, pp. 197-205.
- ^ Glazer-Hockstein C, Dunaief JL. "Could blue light-blocking lenses decrease the risk of age-related macular degeneration?" Retina. 2006 Jan;26(1):1-4. doi:10.1097/00006982-200601000-00001 PMID 16395131
Margrain TH, Boulton M, Marshall J, Sliney DH. "Do blue light filters confer protection against age-related macular degeneration?" Prog Retin Eye Res. 2004 Sep;23(5):523-31. PMID 15302349
- ^ "Information from Your Eye M.D.: Sunglasses." November 2003.
- ^ article by Charlotte Remé, who also developed the guidelines/norms for Switzerland:
Remé, Charlotte (1997). Lichtschutz der Augen. [Light protection for Eyes] Der informierte Arzt – Gazette Medicale, 18, pp. 243-246
- ^ "Sunglasses Raise Risk of Cancer". Express.co.uk. 2007-06-03. http://www.express.co.uk/posts/view/8739/Sunglasses+raise+risk+of+cancer. Retrieved 2010-05-13.
- ^ Leow YH, Tham SN. "UV-protective sunglasses for UVA irradiation protection." Int J Dermatol. 1995 Nov;34(11):808-10. PMID 8543419.
- ^ "Sunglasses and fashion spectacles—April 2003". Accc.gov.au. . Retrieved 2010-05-13.
- ^ – Some Sunglasses Are Cheap In Price Only
- ^ "10 most wanted bank robbery suspects". ABC Local. 2012-09-19. http://abclocal.go.com/ktrk/gallery?id=8816697&photo=2. Retrieved 2012-11-26. "In each of the instances, the female suspect wore a distinctive wig and sunglasses to conceal her identity."
- ^ no author (2004). Requirements of European Directives and Standards Relating to Sunglasses.. Retrieved 21 September 2009.
- ^ no author (2002). Public eye looks over new standard for sunglasses (2002-01-20). website of Standards Australia. Retrieved 21 September 2009.
- ^ MB Optics Safety (2006). The ANSI Z87.1-2003 standard. Retrieved 22 June 2011.
- ^ NASA website (retrieved on 21 September 2009)
- ^ http://www.silhouette-international.com/silhouette/press/meilensteine_eng.doc
- ^ Optikum, Unabhängiges Augenoptik-Panorama. "optikum, UNABHÄNGIGES AUGENOPTIK-PANORAMA – Silhouette Titan Minimal Art Space Edition – Die leichteste Brille des Universums". Optikum.at. http://www.optikum.at/469.htm. Retrieved 2010-05-13.
- ^ ""no author" ("no date"). American Optical Flight Gear Vintage Sunglasses. on "AAA Pilot Supplies" (retrieved on 21 September 2009)". Aaapilots.com. 1969-07-20. . Retrieved 2010-05-13.
- ^ no author (2006). Look Sharp While Seeing Sharp. (Originating Technology/NASA Contribution). Spinoff 2006, NASA Scientific and Technical Information (STI). Retrieved 17 October 2009.
- ^ Welcome To Pech Optical
- dead link]
- ^ Recommended Type of Sunglasses for People with Large Nose
External links
|Wikimedia Commons has media related to: Sunglasses
- What Makes A Good Pair Of Sunglasses by George W. Waltz 1951 Popular Science article on sunglasses and the method of mass production at that time period.
- 'How to Choose Sunglasses for Your Face Shape'
This article uses material from the Wikipedia article sun glasses, which is released under the Creative Commons Attribution-Share-Alike License 3.0.


text:
Tier-2 leaders named for Qwest/CenturyLink
Denver-based Qwest and Monroe, La.-based CenturyLink, which are in the midst of seeking required approvals for their proposed merger, this week appointed more than 60 executives to leadership positions for the combined company. About 45 percent of those positions will be filled by Qwest executives after the merger closes, expected as early as the first quarter of 2011.
In June, the companies revealed their 12-member senior management team, which will include four Qwest executives.
This week's "tier-2" announcement involves the executives that will report to senior management.
Of particular significance for Colorado is the appointment of Kenny Wyatt (pictured) to the role of Mountain Region President. Wyatt will be responsible for operations in Colorado, Montana, Utah and Wyoming and will be based in Denver. He will report to chief operating officer Karen Puckett, who will be based in Monroe, which is where the combined company will be headquartered. Wyatt is currently CenturyLink's South Central Region President. A former Sprint executive, Read more…


text:
Michael Wu, Ph.D. is Lithium's Principal Scientist of Analytics, digging into the complex dynamics of social interaction and group behavior in online communities and social networks.
Michael was voted a 2010 Influential Leader by CRM Magazine for his work on predictive social analytics and its application to Social CRM.He's a regular blogger on the Lithosphere's Building Community blog and previously wrote in the Analytic Science blog. You can follow him on Twitter at mich8elwu.
Welcome back, and thank you for being patient with me during my relocation to Lithium's new office in San Francisco. It has been a very frantic week for me. After several weeks of digression, we can finally revisit the topic of cyber anthropology – the social anthropology of online communities and social networks. I've previously written about the difference between communities and social networks and their distinct roles in building and maintaining relationships. In those posts we examined the structure of communities and social networks in isolation. In reality, however, they coexist and overlap each other – at any given time we are part of many communities, and are connected to people in these communities as well as those beyond our communities.
Today I will give you a unified view of communities and social networks in an attempt to understand how these two social structures fit together. This post is a little more abstract and theoretical in nature – in comparison to previous posts – but I believe it will give you a novel perspective on the inner workings of social media.
The Social Networks inside Communities
As we've learned, most of the strong relationships in our personal social network (a.k.a. personal network) were developed in communities that were once part of our lives. Figure 1 illustrates the dynamics of a person (hypothetically Bob, the red dot in Figure 1) joining a community (yellow).
From personal experience, you probably recognize the fact that when someone joins a community, the rest of his personal network does not necessarily join with him. That is, your friends generally do not follow you everywhere, at least not immediately, and not all of them. Why is this? The main reason is because people have different interests and they have communities of their own. Upon joining the community and interacting with other community members, Bob would create weak ties (dotted lines). If the interactions were mutually desirable and have the proper environment to develop over time, then some of these emerging weak ties will grow into strong relationships, which will ultimately become part of Bob's personal social network.
As you can see, it is definitely possible to have social networks within a community. In fact, social networks will develop naturally in communities that provide a rich medium for their members engage and interact. Members who have invested much time and effort in the community will tend to have a more extensive network (e.g. the orange dots), whereas new members (e.g. the red dot) will tend to have fewer connections. But this is just one part of Bob's social network (i.e. the localized social network inside this particular community).
In reality, the picture is more complicated. Because Bob, like most people, doesn't just belong to one community. Most people are part of several communities at any given time. Figure 2 illustrates this situation, where Bob is actually part of three other communities (blue, green, and orange). Note that within each of these communities, there are actually complex network structures just like the yellow community, but we've kept these redundant details hidden.
The Communities inside Social Networks
Although the entire social network covers the globe, your personal network (which includes only your direct connections) is more limited in scope. This means we can examine Bob's network in greater detail. Since this section focuses on Bob's personal network, we will hide all the relationships that are not directly connected to Bob. As we discussed in the previous section, Bob has just joined the yellow community, he didn't know anyone in this community before and hasn't established any long term relationship yet. So if we hide the details and only look at Bob's personal network, he actually has no connections in the yellow community.
However, Bob is already a member of three communities, so we can examine the relationships that Bob has established in these communities. Figure 3 shows all of Bob's friends and the communities they belong to (the black lines indicate direct connections to Bob). It is not surprising to see that Bob has friends in the blue, green and orange community. Moreover, one of his friends (the blue dot) shares two common communities (blue and orange) with Bob. Notice that Bob also has friends that do not share any communities with him. These friends are in the pink, violet, and cyan community respectively. Where do these friends come from?
Remember, as we grow and our lives change, it is natural for people to move away from a community and move into another. Since we maintain the relationships we established in communities with our social network, it is therefore logical to find relationships across community boundaries. This means sometime in the past, either Bob has left the pink, violet, and cyan communities, or his friends have left their common communities and then subsequently joined the pink, violet, and cyan communities.
Now that we understand the community structure around Bob, we can begin to fill in the network structures. Figure 3 is incomplete because it doesn't show how Bob's friends are interconnected among themselves. If none of Bob's friend knew each other, then this picture would be correct. However, this is unrealistic, because the social dynamics (such as the triadic closure rule, homophily, etc) that govern tie formation tends to create cliques among friends.
This brings us to Figure 4, which shows the structure of Bob's personal social network, and how it fits with the community structure around him. The black lines are Bob's direct relationships, and the gray lines are connections among Bob's friends. Together they make up Bob's personal network. What do you see inside this network? Do you see communities? Not only will you find communities within personal networks, communities exist inside the global social network too. This will be more obvious if you recognize the fact that the global social network includes everyone in the world. Consequently, any community consisting of a subset of the world's population must lie inside this global network.
So what have we learned? Although the topological structure of communities and social networks are very different, and each social structure has its unique functions in human history, they are tightly interwoven. In fact they complement each other.
We have examined the social structure around a hypothetical person, Bob, and it looks something like Figure 4. But this is only for one person. What is not shown in this picture is that everyone of Bob's friend has a similar social structure around him/her. This also applies to all the people inside the communities that weren't shown, because they weren't directly connected to Bob. In fact, these social structures exist around every single human being on earth. The complexity is truly perplexing, yet beautiful.
Alright, now that we (hopefully) have a more holistic understanding of community and social network, as well as how they fit inside each other, we can begin applying it. Next time, we will use this knowledge to analyze an interesting social media platform – Twitter. But, before that, maybe we can have some discussions around this topic. Comments of any kind are always welcome, so keep them coming.
good discussion on building social network within a community or a community with a social network. actually, both of cases have deep meanings: social network within a community means that we can have certain-type of 'closeness/friendship' build on top of the professional/interests network and community within a network means that we can turn friendship into professional/interests relations.
The diagrams say it all. A great way to explain this concept.
I was particularly interested in knowing the influence of trend-setters on this. From what i have noticed, individuals tend to follow their friends not just within a particular network, but also from one network platform to the other (for example, when i started with the social media, Orkut was pretty big in India. Today i am more active on Facebook. Reason: My friends whom i looked upon as tech savvy, migrated to fb).
From the perspective of the diagrams shown, if we say that the trend-setters usually are the focal point where most of these communities overlap, would that be right?
Hello Dr Chen,
Thank you for stopping by Lithosphere and commenting on my blog.
This is a great comment to this somewhat abstract and theortical post. I just like to rephrase the 2nd point you mentioned.
1. People with similar interests and professional groups can turn into long term friendships.
2. You can find groups among your friends with similar interests and professions, which form cliques in your personal social network.
Great observation!
Thanks again for the excellent comment.
Hello Nirmal,
Thank you for the question.
To answer your question, that really depends on what you mean by trend-setter, because trend setter can have many meanings. From the context in your question, I think trend-setters means adopters of technologies who like to explore new networks, right? Certainly this one kind of trend-setter, but I would not generalize my comment here to other types. To avoid future confusion, I am going to call them network explorers for the time being, and I think from my answer below you will understand why.
What I've shown is the overlap of communities within a social network, but I think what you were asking is the overlap between different social network platforms. Keep in mind that the different social network platforms is an artificial separation of our social network. Whether your friends are on Orkut or FB, they are still your friends, and they are part of your personal social network. With that in mind, I think that the network explorers are probably at the overlap between different social netowrk platforms (if we view different network users as a macroscopic communities). However, they do not necessarily have to be trend-setters. It is certainly possible that these people move to another network created some ties in the new network, but found it not as good as the old one, then move back. That being said, I believe that explorers, early adopters, who tend to explore other networks and communities will tend to be at the overlap between communities (as shown in my diagram). That is a direct consequence of the fact that these explorers tend to have much movement between communities/networks.
Alright, I hope I've address your question. Thanks for asking it and I hope to see you around on Lithosphere again.
Hello Peeyoosh,
I've written quite a bit on influence in communities, and you can find them through the links provided in this summary blog article.
Thank you for the comment.
I like the term "network explorers" . . . could this idea be linked to a computational "curiosity" metric? Any ideas?
Hello Colleenp
Thank you for asking the question.
I think we can use it as a proxy for curiosity, but I wouldn't just take that literally. Many people often play with terms and they can be very misleading.
For example, if the metric is a measure of network overlap, it means network overlap, and that is it. Although network overlap can be a result of people who are curious and like to explore different networks/communities, it doesn't means that network overlap = curiosity. For example another user can have high network overlap due to the fact that he's a traveling salesman, and his work requires him to move from place to place, therefore switch between many communities/networks. But he is totally not curious at all. In fact he hates exploring. In this case, he will have a high network overlap metric, but he may be totally not curious at all. His high network overlap is simply a result of the fact that his work require much traveling.
So one danger about interpreting data is don't try to over-generalize the data. A metrics only mean what it is designed to measure, and that is it. We should not over-interpret it, or else it could lead you to a totally wrong conclusion.
However, we do compute a interest focus metric (bease on the participation entropy) in our communities. It measure how focus a person's participation is. I think that is a much better proxy for curiosity, although it is still not equal to curiosity. It tells how focus a user's interest is. To measure curiosity, we would have to design a metric that specifically measures that. It may use a combination of network overlap, interest focus, and more, because there are many behavioral traits that are a result of curious behaviors.
I hope this addresses your question. Thanks again for this great question. See you around.
Soy Boliviano y uno de los pocos antropologos especializados en Redes Sociales Virtuales, tengo un blog donde escribo diatribas sobre el tema. (http://antradio-pod.blogspot.com/)
El análisis me pareció fundamental, en especial por que se basa fuertemente en las estructuras de redes que no son extrañas para la antropologías.
Me quedo con una pregunta ¿Los antropologos están listos para analizar las modificaciones de las conductas pautales en este nuevo ecosistema?
Hello Jean,
Hmm, unfortunately Spanish is not my native language. So I've used Google Translate to help me. For those who can't read Spanish (like me) here is what Jean said according to Google.
I am Bolivian and one of the few anthropologists who specialize in Virtual Social Networks, I have a blog where I write diatribes on the subject. (Http://antradio-pod.blogspot.com/)
The analysis seemed essential, in particular that relies heavily on network structures that are alien to anthropology.
I'll take one question: Anthropologists are ready to analyze the behavior pautal changes in this new ecosystem?
Now my response.
I think that anthropologist are ready. To understand social media, we need a collaboration between many disciplines. I've used everything from statistics, machine learning, data mining, social network analysis, graph analysis, econometrics, sociology, social psychology, and social anthropology to understand the "social" and user behavioral aspects of social media. It really spans everything from the really rigorous mathematics and statistics, to the softer side of science. Social is not just a challenge of one discipline, it is really every aspects of our life. So I think it is important to look at the problem from multiple lens. If you are interested in the basics of social network analysis. I've written a short blog article on that: Social Network Analysis 101.
Although it is in Spanish, I still appreciate your comment 🙂
I presume you are using the term social network and community for both online and offline relationships.
Hello Larry,
Yes, social network and community are both very robust social structures that existed thousands of years before there are even computers. The idea here is to see if we can get a better understand of the "social" aspect of social media using principles from social anthroplogy, social psychology, social economics etc. Because it is these social aspects of social media that makes social media work. Technology is only an enabler of what the social things that people normally do for ages.
If you have not read the earlier articles in this series, I recommend checking them out:
I'm sure that if you read the prequel to this article, things will make a lot more sense. But thanks for asking the clarification question, and hope to see you around Lithosphere next time.
Hi Michael,
As every marketer would like to know who are the influencers to best spreed out the message and to attract more users/customers, the next task would be: Find and Engage the influencers (they are from the intersection of friend network and the professional network), and let them to market your brand/products/services. That reads, there is a need to find out the answers for the questions: the quality of the influencers friend network & professional networks (against your business target). from business point of view, you wand influencers to' develop' your users/customers from BOTH of their friend network and professional networks. Then there is an question a marketer has to find out: why the influencers 'works' for him...and this is key to social CRM from business point of view.
one more thing, from my facebook experiences, facebook provides more automatic notification tools for friend networks, NOT PAGES. And this is also a reason we need to blend friends network and professional network.
Hello Dr Chen,
Great comment.
Finding influencers is definitely the first step and I've created algorithms and blogged about this topic earlier (See My Chapter on Influencers). Engaging the influencers to co-create value is a much longer term problem that involves strategies, business processes and a change in corporate culture. I've also speak about this topic at webinars and panels, even though I have not blog extensively about it.
Base on my simple 6-factor influence model, we must take into account of the targets (people we want to influence) when looking for influencers. These targets are precisely the personal network of the influencers. Remember, the friendship network and professional network are both part of someone's personal social network. The division between these two network is quite artificial, and is only a result of the inability of social networking platforms to assign and keep track of the different types of relationships we have (See Social Network Analysis 101).
One way to design an algorithms that identifies influencers would be to filter out the irrelevant targets first, provided that we know something about the target. Then we can look for the influencers among the relevant targets. This will ensure that the targets are matched to the business and marketers would know why the particular identified influencers works.
I hope this address your commnet concerning why a particular influencer works for a particular target audience. Thanks for commenting and hope to see you next time.
Hi Michael,
As someone with an anthropology education I'm pleased that the world has stumbled upon a value to our discpline. A relief that my student loans weren't in vain.
My add to this: I've come to think of social media as a real-time annotated Rolodex. Many say that they use social media to keep in touch with people they know IRL Sometimes with people they met on other platforms. Hardly ever do I hear that people meet and become close cross-network without meeting in person. Thus we become voyeurs of other people's network interactions.
Communities allow us to engage with strangers without the implication that we must be introduced by a common network connection, such as on Linked-in. And those relationships are unlikely to expand outside the Community unless they are bolstered with an IRL engagement.
Until online engagement approximates IRL engagement of people in related networks, with real emotional bonding of some kind, online remains a model of IRL engagement, merely supporting IRL. Maybe it's better that way - don't know yet.
thanks, Michael for addressing my question on the influencers. your suggestionwould be a feasible approach (i would call those people the 'Conditional Influencer'):
One way to design an algorithms that identifies influencers would be to filter out the irrelevant targets first, provided that we know something about the target. Then we can look for the influencers among the relevant targets. This will ensure that the targets are matched to the business and marketers would know why the particular identified influencers works.
Hello Maggid,
Glad to know a real anthropologist by training. I believe that the softer science (sociology, social anthropology, social psychology, social economics) will definitely be valuable in terms of understanding the social aspect of social media. As I mentioned in my reply to Jean social is inherently a interdisciplinary subject. We need both the hard core rigorous science (mathematics, machine learning, statistics, social network analysis, etc.) as well as the softer science to understand human behavior.
I believe that (in-real-life) IRL interaction and talking to people face to face still has its value in building strong relationships. Online communication platforms gave us a much wider reach, but also limited us in the depth of interaction. However, I would argue that it is possible to develop strong relationships if people spent enough time together and there is enough reciprocity between them. I've definitely get to know quite a few members on the lithosphere community quite well. Eventually, we linked up on LinkedIn, and I've even met some of them IRL. So, even though I agree that it is much harder to build close and strong relationships online than IRL, I think it is definitely possible.
As we learn more about human behavior, psychology and needs, we may be able to develop a platform that enables deeper level of interaction, which could then make online relationship building easier. That would require a fusion between the softer sciences with the rigorous science.
Thank you for the comment, and hope to see you next time.
Hello Dr Chen,
Welcome back. Great term. I can see your probabilistic modeling expertise leaking out from this term.
However, the set of influencers may be outside the set of potential targets. When filtering out the irrelevant targets, we only get the set of potential targets. The set of conditional influencers, as you call it, is the set of all 1st degree connection to set of all potential targets. The real influencers are within this larger group. That's what I ment when I say finding influencers among them (sorry for not being clear).
Thanks for the comment and see you around.
Hello Dr Chen,
is, sociologicaly spoken, 3 types of social group (small, medium and big) more pointed to analyse web sociation and influencing?
Michael -
Thanks for this useful description of the interplay between Communities we participate in and the Social Networks we have as individuals.
I'm intrigued by the conversation - and your related posts - around influence. Recently, I've been wondering about the various roles played by individuals within communities - and how roles - and their respective "behaviors", interact to impact the stability and integrity of a community. In that sense, I think "influencer" would be less of a role and more of a descriptor of community-building efficacy ... meaning that you can become an influencer for a given target audience by fulfilling any number of more specific roles (e.g. moderator, aggregator, networker, etc.). Does that sound right to you?
How do others feel about the importance of understanding roles within a community? Is such an understanding useful and actionable? For example, if we could identify pivotal roles in certain community "types" that must be filled effectively, then this might lead to some sort of community health or maturity metric. Would love to hear more about the role of roles in community at some point.
- Skip
Hello Skip,
Haven't seen you for a while. Welcome back.
Roles in community is also a feature that arise quite naturally. Because members have a life cycle in the community, more senior members tend to take on some functional roles because they are passionate about certain common goal in the community.But role and influence are not really the same. Althugh I've found that influencers tend to correlate highly with superusers (product experts in the community). This is not surprising because domain credibility is a necessary (althought not sufficient) factor for being influential.
What I've found from analyzing our community data is that depending on the types of communities (e.g. support, enthusiast, innovation community, etc.) different roles are important. For example, in support communities, the product expert role is extremely important, whereas in a enthusiast community, the discussion leader roles is more critical, and finally, in an innovation community, the critics roles is essential. However, in a healthy community, we usually need a mix of different roles.
The understanding of roles is definitely actionable. For example, if you are a support community, you want to have more product experts. But if all you've got is critics and discussion leaders, you may want to focus on cultivating more product experts. We are currently working on metrics that enables our application to automatically identify users having these functional role characteristics.
I will definitely make note of your interest and maybe write a series on the different roles in different types of communities.
Thanks for the comment, and I hope to see you next time. Actually, this week's post will be about influencers and whether they really matter or not.
Thanks, Michael. Your response regarding roles is quite helpful. I like the characterization of community types (support, enthusiast, innovation) you surfaced as well. Do you have any posts or references you'd suggest we review to gain a deeper coverage of community types? I think this may have been covered to some extent in Bernoff and Li's Groundswell, but its been a while since I read that.
Hello Skip,
You are welcome.
Personally, I don't know, off the top of my head, a post on these community type. But communities can really be used for anything. And there are can be many different classification of communities based on size, age, purpose, audience, industry, etc.
The 3 types that I mentioned is a segmentation of communities by purpose, and it arises from an analyis of our client base. But for each of these three types, they can also be divded by audience into B2C, B2B, or internal, and industry, as well as other attributes such as size and age.
We analyze that because our benchmark clustering algorithm is based on these 5 different dimensions. There is a tribal knowledge base article on this. I've also analyze some participation data base on these segmentation in a post I wrote on the Economics of 90-9-1.
In my limited view, early on, business uses of community has been primarily to cut support cost. So support communities has been prevalent for a long time, (10+ years). As social media gain popularity, more and more companies are using it to drive marketing and sales. So later on, maybe 3 years ago, more and more companies are adopting the use of enthusiast communities for marketing and sales. Then shortly after, people are realizing the importance of value co-creation, that is why the innovation use case was created. But this is only my limited view from our client base.
Sorry I couldn't provide any more detail reference. I will seriously consider writing a post about this topic. Thank you for asking the question.
The Strength of Weak Ties
cafe press needs to have neckties with these social network patterns.
Michael, Through Facebook API can we find our fans (fans of our FB page) likes and their further friends likes/dislikes?
Hello Gunjan,
Thank you for the questions.
I don't believe you can get any non-public data on fan's friends and/or their likes/dislikes through the Facebook API. I believe they have to opt-in specifically for you to do that. And most people are not going to let you do that. That is why so few people have Facebook data for any analytics.
Alright, thanks and see you later on Lithosphere.
Dear Michael!
Thank you so much for your brilliant articles about interactions between social networks and communities! I was so inspired by them that decided to share my impression to others. I have translated all of your 5 articles of your mini-series into Russian and published them on habr.ru - the one of the influensest IT community in the russian-speaking world. We have awful huge lack of the discourse in Russian on such topics. I hope you don't mind.
Here are my translations:
How Do People Become Connected? Community vs. Social Networks 2
From Weak Ties to Strong Ties: Community vs. Social Networks 3
Maintaining the Strong Ties: Community vs. Social Networks 4
Hello Maxim,
Thank you for the comment and for your interest. I'm very glad to hear that you are inspired by my work.
Thank you for letting me know that you've translated this mini-series into Russian. I would have completely miss that if you didn't tell me. I think that is great, and I really appreciate your effort in helping to diseminating these knowledge.
Personally, I certianly don't mind you translating and re-publishing my work, however, our marketing does request that you follow good social web etiquette.
1. Mention the author: Dr. Michael Wu or Michael Wu PhD.
2. Mention the fact that I'm the principal scientist at Lithium.
3. Link back to the original source for the blog article.
You can see examples of how others does this when re-publishing my work at this URL. I see that you already did #1 and #2, so you just need to link back to the source article like what MyCustomer.com did at the end of the re-post.
Thanks again and hope to see you around Lithosphere in the future.
Michael, in fact my translations do have the back link to your original articles. The form of publication on Habr.ru suggests you to put a back link in a special field. And then this link is depicted at the end of the publication under the name of the author of the original text. Look at the image beneeth. Is it not enough? Should I dublicate the back link in the text of publication directly?
Hello Maxim,
Thank you for the clarification. In this case, you are all set then.
I just didn't know this convention at Habr.ru 😉
Thanks again for all the translation and re-publishing.
And see you next time.
Even if I am late at it, Welcome back Michael.
I agree that a shared interest is a key driver for a community, just like neighborhoods, people who live their comeback because they live there and have a shared interest within that community. "A rough mind map", but what really drives retention? I figure if I purchase a house in that neighborhood that automatically displays a vested interest. But if I rent, what's my standpoint?
I would like to gain a deeper understanding of community types, can you suggest anymorearticles on this matter?
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Four senior faculty awarded research leave grants
Brandeis University has awarded four senior faculty research leaves for spring 2014. These competitive grants relieve the faculty member of teaching duties for a semester, providing flexible time for major research projects and a small amount of funding for research expenses.
"We received many strong proposals, and the selection committee was extremely impressed by the quality and breadth of the work that our colleagues are doing," said Irving R. Epstein, PhD, the Henry F. Fischbach Professor of Chemistry and senior adviser to the provost for research.
The 2014 recipients and their projects:
- Caren Irr, PhD, (English) is working on a project exploring the literary and intellectual history of orphans in a cross-cultural context from the United States and England to Korea, Brazil, East Africa and Russia.
- Ellen Schattschneider, PhD, (Anthropology and Women's and Gender Studies) will be working on her second book, "The Fetish Goes to War: Violence and its Simulacra in Modern Japan." The book explores how dolls and human-shaped figurines have helped manage memories of the dead in modern Japan, during war and peace.
- Faith Smith, PhD, (English, Women's and Gender Studies, and African and Afro-American Studies) will use novels, memoirs, travelogues, newspapers and photographs as sources for her book, "Whose Modern? Caribbean Cultural and Intellectual Formations, 1885-1915." The work crosses imperial boundaries to examine the Caribbean people's engagements with their own and others' modernities, at a historical moment when they were keenly aware of being subject to the intentions of either Britain, France or Spain, at any given moment (Haiti no less so for being independent), and, particularly after 1898, the United States.
- Govind Sreenivasan, PhD, (History) will be exploring how a seventeenth century German peasant's legal conflicts and exile reflect the social history of peasants in early modern Europe, and how the struggles of European peasants compared to those in non-Western Eurasian societies, including Ottoman Turkey and Qing China.
Return to the BrandeisNOW homepage
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