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Concrete corrosion of wastewater collection systems is a significant cause of deterioration and premature collapse. Failure to adequately address the deteriorating infrastructure networks threatens our environment, public health, and safety. Analysis of whole-metagenome pyrosequencing data and 16S rRNA gene clone libraries was used to determine microbial composition and functional genes associated with biomass harvested from crown (top) and invert (bottom) sections of a corroded wastewater pipe.
Taxonomic and functional analysis demonstrated that approximately 90% of the total diversity was associated with the phyla Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria. The top (TP) and bottom pipe (BP) communities were different in composition, with some of the differences attributed to the abundance of sulfide-oxidizing and sulfate-reducing bacteria. Additionally, human fecal bacteria were more abundant in the BP communities. Among the functional categories, proteins involved in sulfur and nitrogen metabolism showed the most significant differences between biofilms. There was also an enrichment of genes associated with heavy metal resistance, virulence (protein secretion systems) and stress response in the TP biofilm, while a higher number of genes related to motility and chemotaxis were identified in the BP biofilm. Both biofilms contain a high number of genes associated with resistance to antibiotics and toxic compounds subsystems.
The function potential of wastewater biofilms was highly diverse with level of COG diversity similar to that described for soil. On the basis of the metagenomic data, some factors that may contribute to niche differentiation were pH, aerobic conditions and availability of substrate, such as nitrogen and sulfur. The results from this study will help us better understand the genetic network and functional capability of microbial members of wastewater concrete biofilms.
Concrete corrosion of wastewater collection systems is a significant cause of deterioration and premature failure. In the U.S., costs associated with maintaining an estimated 800,000 miles of wastewater collection infrastructure are approximately $4.5 billion per year [1]. Many systems may be beyond their design life and must be replaced because they cannot be rehabilitated [2]. Failure to adequately address the deteriorating infrastructure networks threatens our environment, public health, and safety. In wastewater collection systems microbial-induced concrete corrosion (MICC) may occur in areas under higher concentrations of hydrogen sulfide (H2S) [3-5]. The primary source of sulfur is sulfate (SO42-) which can be reduced by sulfate-reducing bacteria (SRB) to hydrogen sulfide (H2S) under anaerobic conditions. H2S is transferred across the air-water interface to the sewer atmosphere where chemoautotrophic bacteria on the pipe surface, including sulfide-oxidizing bacteria (SOB), convert the H2S to biogenic sulfuric acid (H2SO4). Biogenic sulfuric acid (H2SO4) can be generated by various microbial species [6-9].
While many of the microorganisms and general mechanism involved in MICC has been known for decades, and recent studies using molecular-based approaches have more accurately described the microbial ecology of these engineered systems [6,8,9], a better understanding of the metabolic processes and functional capabilities is needed to develop new approaches to mitigate MICC and its associated effects. The objective of this study was to characterize the microbial community of concrete wastewater biofilms and their functional capability based on molecular analyses of metagenome libraries and to compare it with 16S rRNA gene sequences from previously generated clone libraries [7-11]. Specifically, we sampled biofilms from two sections of a severely corroded concrete wastewater pipe to obtain a better understanding of microbial community colonization processes and mechanisms of concrete deterioration. To our knowledge this is the first published report utilizing metagenomics to elucidate microbial community functional capabilities involved in MICC in wastewater collection systems.
Sampling and extraction of total DNA from biofilms
Biofilm samples were collected from two sections of a corroded concrete sewer pipe located in the Cincinnati metropolitan area. The excavated pipe was installed in 1949 and exposed to residential waste. Biomass was removed from the crown (top section of the pipe, TP) and invert (bottom, BP) sections using a sterile metal spatula by scraping approximately 4 cm2 surface area of each material. Biomass was then transferred to sterile tubes and stored at −20°C. Total DNA was extracted using UltraClean Soil DNA kit following the manufacturer's instructions (MoBio Laboratories Inc., Solana Beach, CA) and used as a template for the generation of pyrosequencing metagenome libraries.
16S rRNA gene sequence analyses
Sequences from Bacteroidetes (n=236), sulfate reducing (n=56) and sulfur oxidizing (n=164) bacteria obtained from a previous study [11] were used to develop phylogenetic trees. Briefly, 16S rRNA gene primers 8F and 787R were used to generate community PCR products, which were then cloned using TOPO TA vectors. Clones were sequenced in both directions and assembled using Sequencher software (Gene Codes Corp, Ann Arbor, MI). Sequences were assigned to specific bacterial groups using MOTHUR v1.19.2 (http://www.mothur.org webcite) with 97% sequence identity as the cut off point for each Operational Taxonomic Unit (OTU). Phylogenetic trees were constructed from the alignments based on the Maximum Likelihood method and calculated using Tamura-Nei model [12]. MEGA v5.03 [13] was used to build trees using 100 replicates to develop bootstrap confidence values. The Classifier tool of the Ribosomal Database Project II release 10.26 [14] and BLASTn [15] were used to classify and identify the nearest neighbors.
Cluster analysis of wastewater concrete biofilms
Cluster analysis based on the transformed (log[x+1]) relative abundance data was used to compare communities associated with different wastewater concrete biofilms. First, we estimated the taxonomic distribution at the genus level of each microbial community from 16S rRNA gene pyrosequences generated in this study and Sanger-chemistry 16S rRNA gene sequences generated in previous studies [7-10]. This information was used to generate Bray-Curtis similarity coefficients of the transformed data using the software PAST v2.03 [16]. This estimator compares the structures by accounting for the abundance distributions of attributes (e.g. species). Dendrograms indicating relationship of biofilms generated by comparing similarity coefficients estimates among sample sites were calculated using the UPGMA method with the software MEGA v5.03 [13].
Metagenomic studies
Pyrosequencing was performed using the 454 Life Sciences GS-FLX Titanium® platform. Prior to sequence analysis we implemented a dereplication pipeline (http://microbiomes.msu.edu/replicates webcite) to identify and remove clusters of artificially replicated sequences, i.e. reads that began at the same position but varied in length or contained a sequencing discrepancy [17]. Filter parameters included a cutoff value of 0.9, no length difference requirement and an initial base pair match of 3 base pairs. Metagenome sequence data (i.e. singleton reads) were processed using two fully automated open source systems: (1) the MG-RAST v3.0 pipeline (http://metagenomics.anl.gov webcite) [18] and (2) the Rapid Analysis of Multiple Metagenomes with a Clustering and Annotation Pipeline (RAMMCAP) [19], available from the Community Cyberinfrastructure for Advanced Microbial Ecology Research and Analysis (CAMERA, http://camera.calit2.net webcite). The analysis included phylogenetic comparisons and functional annotations. All analyses were performed with an expected e-value cutoff of 1e-05 without preprocessing filtering. The metagenomes generated in this paper are freely available from the SEED platform (Projects: 4470638.3 and 4470639.3). Taxonomic relationships between metagenomes were analyzed by two complementary analyses using the MG-RAST pipeline. First, 16S rRNA gene sequences were retrieved and compared to a database of known 16S rRNA gene sequences (e.g. SSU SILVA rRNA database project). Each read that matched a known sequence was assigned to that organism. In the second analysis putative open reading frames (ORF) were identified and their corresponding protein sequences were searched with BLAST against the M5NR database [18]. The M5NR is an integration of many sequence databases into one single, searchable database. This approach provided us with information for assignments to taxonomic units (e.g. class, families and species) with the caveat a protein sequence could be assigned to more than one closely related organism. Taxonomic assignments were resolved using the lowest common ancestor (LCA) approach [18].
Functional analysis and reconstruction of metabolic pathways
ORFs were identified and their corresponding protein sequences were annotated (i.e. assigned functions) by comparison to SEED, Pfam, TIGRfam and COG databases [18,19]. Identified proteins were assigned with their respective enzyme commission number (EC). Prior to quantitative characterization, counts were normalized (relative abundance) against the total number of hits in their respective database (e.g. SEED, COG, etc.) using effective sequence counts, a composite measure of sequence number and average genome size (AGS) of the metagenome as described by Beszteri et al.[20]. Raes and colleagues [21] defined the AGS as an ecological measure of genome size that also includes multiple plasmid copies, inserted sequences, and associated phages and viruses. Previous studies [20,21] demonstrated that the relative abundance of genes will show differences if the AGS of the community fluctuate across samples. The ChaoI and ACE estimators of COG richness were computed with the software SPADE v2.1 (http://chao.stat.nthu.edu.tw webcite) [22] using the number of individual COGs per unique COG function. The proportion of specific genes in metagenomes also provides a method for comparison between samples. By dividing the AGS to the amount of DNA (in kb) per function-specific gene, one can determine the proportion of genomes in the metagenome that are capable of that function [23]. However, direct comparison of the distribution of different functions (i.e. gene) was not established between the metagenome, since length and copy number of the gene was not incorporated in the formula. To define whether a gene was enriched in the environment we calculated the odds ratio or the relative risk of observing a given group in the sample relative to the comparison dataset [24]. The odds ratios were calculated as follows: (A/B)/(C/D) where A is the number of hits to a given category in the x dataset (e.g. TP metagenome), B is the number of hits to all other categories in the x metagenome, C is the number of hits to a given category in the y dataset (e.g. BP metagenome), and D is the number of hits to all other categories in the y dataset. We then used the metagenome profiles to calculate the statistical differences between the two samples based on the Fisher's exact test with corrected q-values (Storey's FDR multiple test correction approach) using the software package STAMP v1.07 [25]. Such randomization procedures were used to find statistically distinct functional groups in each of the wastewater pipe biofilms. Genes with an odds ratio >1 and q < 0.05 were defined as enriched and genes with an odds ratio <1 and q < 0.05 as under-represented.
Taxonomic assignments of metabolic genes
Sequences assigned to the sulfur and nitrogen pathways were identified and retrieved from MG-RAST and RAMMCAP output files (see Metagenomic studies section). Selected genes were taxonomically classified by BLASTX analyses against the NCBI non-redundant protein sequence (nr) database using the CAMERA 2.0 server [26]. Assignment and comparison of taxonomic groups and tree representation of the NCBI taxonomy were performed using the software MEGAN v4.67.1 [27]. The metagenomes were compared at the genus level (when available) using absolute reads counts with default parameters for the lowest common ancestor (LCA) algorithm of min-score of 35, a top-percent value of 10% and min-support of 5.
Results and discussion
Metagenome library construction
In this study, we analyzed the microbial communities of biofilms established on the top (TP) and bottom (BP) of a corroded wastewater concrete pipe. The excavated pipe sections were installed 60 years prior to this study and were replaced due to integrity failure resulting from corrosion (i.e. the crown losing a significant portion of original width). A total of 1,004,530 and 976,729 reads averaging 370 and 427 base pairs for the TP and BP metagenomes, respectively, were analyzed in this study (Table 1). We identified and removed artificially replicated reads, which represented a total of 14% and 12% of sequences from the TP and BP metagenomes, respectively. Less than 50% of our reads were annotated as specific genes or functional group by either CAMERA v2 or MG-RAST v3 (Table 1). The relatively low number of annotated genes is common in metagenomic studies [28-30] and is primarily due to the relatively small and biased diversity of genomes sequenced, novel genes yet to be placed in functional groups, and sequencing and processing errors. For diverse and not well-understood systems such as wastewater biofilms, annotation of gene functions can also be limited by the extent of the database of previously sequenced and characterized genes [31]. Nonetheless, high-quality reads with a comparable average genome size were generated in this study, which allowed us to compare the metagenomic data, in terms of what proportion of genomes harbor a particular function [23].
Table 1. Characterization of 454 pyrosequenced libraries from the microbial community of biofilms
Wastewater biofilms
The taxonomic classification of 629,161 (TP) and 641,853 (BP) sequence reads was assigned using the SEED database (MG-RAST v3). Based on our results, Bacteria-like sequences dominated both samples (>94% of annotated proteins) (Table 1). Approximately 90% of the total Bacteria diversity was represented by the phyla Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria (Figure 1). The bacterial community was diverse with representatives of more than 40 classes. Taxonomic annotation of the functional genes profiles (i.e. annotated proteins) displayed a similar pattern of diversity to taxonomic analysis based on 16S rRNA genes identified from the metagenome libraries ( Additional file 1, Figure S2).
Additional file 1. Figure S1. Distribution (%) of sequences identified to particular subsystems (SEED) in metagenomes of wastewater biofilms.Figure S2. Distribution of bacterial classes on concrete wastewater pipes as determined by taxonomic identification of 16S rRNA genes recovered from metagenome libraries. Numbers in brackets represent percentage of each group from the total number of sequences. Legend: 1. unclassified Bacteria domain, 2. Actinobacteria, 3a. Bacteroidia, 3b. Flavobacteria, 3c. Sphingobacteria, 4. Chloroflexi, 5a. Bacilli, 5b. Clostridia, 6. Fusobacteria, 7a. Alphaproteobacteria, 7b. Betaproteobacteria, 7c. Deltaproteobacteria, 7d. Epsilonproteobacteria, 7e. Gammaproteobacteria, 8. Synergistia and 9. other classes each representing <1%. Groups (phylum): 3. Bacteroidetes, 5. Firmicutes, 7. Proteobacteria . Figure S3. UPGMA cluster analysis of Bray-Curtis similarity coefficients for biofilms in wastewater systems. Sample types were classified by their taxonomic dominant group within the sulfur biogeochemical cycle: sulfur-reducing bacteria (SRB) and sulfur/sulfide-oxidizing bacteria (SOB). Location of biofilm: bottom (a), middle (b), top (c) and outdoor (d). Figure S4. Phylogenetic affiliation of phylotypes identified as Bacteroidetes from each biofilm: top pipe (TP, gray) and bottom pipe (BP, black). Clones were identified by genus or order (*) and percentage of each representative sequence in their respective libraries is provided in the brackets. The tree was inferred using maximum likelihood analysis of aligned 16S rRNA gene sequences with bootstrap values from 100 replicates. Box indicates the two most dominant phylotypes. Figure S5. Phylogenetic affiliation of Deltaproteobacteria phylotypes identified as sulfate-reducing bacteria (SRB) from each biofilm: top pipe (TP, gray) and bottom pipe (BP, black). Clones were identified by genus or family (*) and percentage of each representative sequence in their respective libraries is provided in the brackets. The tree was inferred using maximum likelihood analysis of aligned 16S rRNA gene sequences with bootstrap values from 100 replicates. Box indicates dominant phylotype. Figure S6. Phylogenetic affiliation of the top 20 most abundant Proteobacteria phylotypes identified as sulfur/sulfide-oxidizing bacteria (SOB) from each biofilm: top pipe (TP, gray) and bottom pipe (BP, black). Clones were identified by genus (*family) and percentage of each representative sequence in their respective libraries is provided in the brackets. The tree was inferred using maximum likelihood analysis of aligned 16S rRNA gene sequences with bootstrap values from 100 replicates. Box indicates dominant phylotype Figure S7. Relative abundance of taxonomic groups based on MEGAN analysis of protein families associated with the sulfur pathway. Each circle is scaled logarithmically to represent the number of reads that were assigned to each taxonomic group. Wastewater biofilms: top pipe (TP, white) and bottom pipe (BP, black). EC = Enzyme Commission number. Figure S8. Relative abundance of taxonomic groups based on MEGAN analysis of protein families associated with the nitrogen pathway. Each circle is scaled logarithmically to represent the number of reads that were assigned to each taxonomic group. Wastewater biofilms: top pipe (TP, white) and bottom pipe (BP, black). EC = Enzyme Commission number.
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Figure 1. Distribution of the Bacteria, Archaea and Virus domain as determined by taxonomic identification at class level of annotated proteins. Numbers in brackets represent percentage of each group from the total number of sequences. Bacteria domain: 1. unclassified, 2. Actinobacteria, 3a. Bacteroidia, 3b. Cytophagia, 3c. Flavobacteria, 3d. Sphingobacteria, 4. Chlorobia, 5. Clostridia, 6. Fusobacteria, 7a. Alphaproteobacteria, 7b. Betaproteobacteria, 7c. Deltaproteobacteria, 7d. Epsilonproteobacteria, 7e. Gammaproteobacteria, 8. Synergistia, and 9. other classes each representing <1%. Archaea domain: 10. Thermoprotei, 11a. Archaeoglobi, 11b. Halobacteria, 11c. Methanobacteria, 11d. Methanococci, 11e. Methanomicrobia, 11f. Methanopyri, 11g. Thermococci, 11h. Thermoplasmata, 12. Korarchaeota [phylum] and 13. Thaumarchaeota [phylum]. Phage (host): 14. Actinobacteria, 15. Bacilli, 16. Cyanobacteria, 17a. Alphaproteobacteria, 17b. Betaproteobacteria, 17c. Deltaproteobacteria, 17d. Gammaproteobacteria and 18. other classes each representing <1%. Groups (phylum): 3. Bacteroidetes, 7. and 17. Proteobacteria, 10. Crenarchaeota, 11. Euryarchaeota.
Some annotated proteins were associated with archaeal genes, and to a lesser extent to viral and eukaryotic genes (Table 1, Figure 1). Specifically, a total of 2,837 (TP) and 8,237 (BP) Archaea-related functions were identified using the SEED database. The majority of the annotated sequences in both samples were related to proteins affiliated with archaea members of the class Methanomicrobia. Although, phages are extremely abundant and diverse in natural systems, we were able to identify only a low number of sequences (696), perhaps due to the loss of viruses during the sample concentration or DNA extraction steps [32]. Nonetheless, the results indicated that the community composition and structure of viruses parallels the distribution of Bacterial representatives [33]. Specifically, phages associated to the classes Actinobacteria, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria and Deltaproteobacteria were found to be the dominant phage sequences in our metagenomes (Figure 1). Phages can potentially be used as biocontrol agents to specifically control some of the bacteria implicated in corrosion. Future studies should focus on the use of viral concentration methods to further study the occurrence of phage sequences that could be use as targets to monitor biocorrosion bacteria in wastewater concrete pipes.
Comparative microbial community analysis
In previous studies, biofilms were analyzed from the surface of primary settling tanks from a domestic wastewater treatment plant [7,8] and from coupons placed in a collection system manhole [9], while our study focused on biofilms from top and bottom of a corroded pipe. In spite of the differences in sample matrix, some trends in the bacterial distribution between concrete wastewater biofilms were observed ( 1). For example, the bottom of the pipe (BP) is characterized by direct contact and long residence time with wastewater, which maintains an ideal anaerobic environment for SRB. In fact, obligate anaerobes of the class Deltaproteobacteria (16%) were the dominant cluster in BP biofilm (Figure 1). The BP harbored anaerobic bacteria normally found in the human gut such as members of the Bacteroidia (11%) and Clostridia (5.1%) classes (Figure 1 and 1). This was also supported by data from 16S rRNA gene clone libraries (Additional file 1, Figure S 1). We also retrieved sequences from the gut-related archaeal species Methanobrevibacter smithii in the BP metagenome [34]. These findings are not surprising, as human fecal bacteria has also been noted in concrete biofilms in previous studies [7-9].
Sections of wastewater pipes exhibit conditions that are favorable for the establishment of oxic zones, e.g., at the top of the pipe (TP). In fact, the dominant TP biofilm members were associated with aerobic and facultative anaerobic bacteria (e.g. ThiobacillusAcidiphiliumXanthomonasBradyrhizobium). The biofilms did not contain a significant presence of photosynthetic organisms (e.g. Cyanobacteria), which dominated biofilms in concrete corroded city-surface structures [10]. The latter is supported by the low number of genes assigned to the photosynthesis subsystems in our metagenome libraries ( 1).
Taxonomic analysis based on annotated proteins show two distinct archaeal communities (Figure 1). The BP biofilm was dominated by the classes Methanomicrobia (55%), Thermococcus (10%) and Thermoprotei (8%). The classes Methanomicrobia (38%) and Thermoprotei (17%) were also abundant in the TP site although Halobacteria (15%) and Thaumarchaeota (7%) were also abundant. Members of the Thaumarchaeota phylum are chemolithoautotrophic ammonia-oxidizers, which suggest that they may be playing a role in the nitrogen cycle in wastewater concrete biofilms [35]. Halobacteriales have been previously reported in wastewater sludge and may suggest the presence of alkaline hypersaline microenvironments in wastewater concrete biofilms [36]. The anaerobic niches in the wastewater pipe provide conditions for methanogenesis as suggested by the annotated sequences associated with genera such as MethanospirillumMethanobrevibacterMethanosphaeraMethanosaetaMethanosarcina, and Methanococcoides[37]. However, the more favourable anaerobic conditions at the bottom of the pipe provide better conditions for this process. Indeed, there are a higher percentage of annotated sequences related to methanogenesis in the BP (69%) than in TP metagenomes (47%). Conversely, more methanotrophic and methylotrophic bacteria proteins were present in the TP (3.7%) than in BP biofilm (1.8%). Specifically, many of the sequences were related to proteins affiliated with MethylibiumMethylobacillusMethylobacteriumMethylocellaMethylococcus, and Methylacidiphilum. The dominant annotated methane-oxidizing bacteria in the TP biofilm were affiliated with Methylocella silvestris, a moderately acidophilic (pH values between 4.5 and 7) and mesophilic species [38]. In general, our analysis identified microorganisms associated with one-carbon compound pathways (e.g. methanogenesis, methanotrophs and methylotrophs), although the importance of these metabolic processes in wastewater pipes remains unknown.
The role of biofilms in MICC
Anaerobic conditions in wastewater collection systems support sulfate reducing bacteria (SRB) that convert sulfate and organic sulfides to H2S, which volatilizes to the sewer atmosphere and redissolves on the top of the pipe. The microbial community at the top oxidizes the sulfide to corrosive H2SO4[39]. Consistent with this observation, analysis of 16S rRNA gene clone libraries showed that the community structures differ, with a dominant presence in the BP of sulfate reducing bacteria (SRB) affiliated to Deltaproteobacteria. Specifically, there were 24 phylotypes represented by the genera DesulfobacterDesulfobacteriumDesulfobulbusDesulfomicrobiumDesulforegula and Desulfovibrio (Additional file 1, Figure S 1). The predominant SRB phylotype (5.4%) in the clone libraries is closely related to Desulfobacter postgatei, a strict anaerobic chemoorganotroph that completely oxidizes acetate to CO2 and reduces sulfur compounds (e.g. sulfate, sulfite, or thiosulfate) to H2S [40]. In the TP sample, most SOB phylotypes (i.e., 39 of 45) are affiliated to the genus Thiobacillus (Betaproteobacteria) ( 1), further supporting the importance of this group in concrete corrosion [41]. During the concrete corrosion process it has been shown that Thiobacillus thioparusT. novellusT. neapolitanus, and T. intermedius are involved in the initial and intermediate stages of colonization, while T. thiooxidans dominate in the final stage when the pH reaches values <3 [3]. In our study the majority of the Thiobacillus-like sequences were closely related to uncultured sulfur-oxidizing bacteria clones. Interestingly, two of the dominant clones in our libraries were identified as neutrophilic T. thioparus and T. plumbophilus (>98.5% sequence identity) (Additional file 1, Figure S 1). T. thioparus oxidizes sulfur and thiosulfate, reducing the medium between pH 3.5 and 5 [3]. T. plumbophilus grows by oxidation of H2S and H2 at pH 4 and 6.5 [42]. There were also sequences with a high sequence homology (>99%) to representatives of the Thiomonas intermedia and Acidiphilium acidophilum, members of the Beta- and Alphaproteobacteria class, respectively. T. intermedia is an obligate aerobe and facultative chemolithoautotroph that produces sulfuric acid at an optimum pH between 5 and 7 [43]. Thiomonas species are unable to denitrify or oxidize ferrous iron. In contrast, A. acidophilum is able to grow autotrophically or mixotrophically using sulfur or reduced inorganic sulfur compounds, as well as heterotrophically using various organic compounds and is capable of reducing iron [44].
Wastewater concrete corrosion involves the interaction of multiple groups and the establishment of these groups are driven by factors, such as the pH of the concrete, and the temporal dynamics of sulfur compounds [41]. The data from different studies conducted thus far suggest that the composition of species involved in concrete corrosion may vary within different wastewater systems. For instance, our study did not find any hyper-acidophilic SOB sequences (e.g. T. thiooxidans, Acidithiobacillus thiooxidans) which had been previously detected in various MICC studies [39]. Okabe and colleagues [8] did not find T. thioparus, although A. acidophilum and T. plumbophilus were present at several stages of the MICC process. Altogether, molecular surveys strongly indicate that the dynamics of multiple microbial groups need to be studied in order to better develop condition assessment tools to monitor the performance of biocorrosion control measures.
Comparative metagenome analysis
Analysis of annotated COG (ChaoI and SACE: ≈3932) also showed that the wastewater biofilm samples are highly diverse. The level of COG diversity is similar to that described for whale fall (3,332), soil (3,394), and Sargasso Sea samples (3,714), but higher than that described for acid mine drainage (1,824) and human distal gut (2,556) [24,45]. Statistical tests based on COG categories or SEED subsystems found no significant difference in community richness between the BP and TP samples (t-test, p = 0.156). The majority of the assigned genes in both metagenomes were identified as part of the SEED database Carbohydrate subsystem (Additional file 1, Figure S 1) with sequences linked to CO2 fixation, Central Carbohydrate and Fermentation subsystems. In both biofilms the single most abundant component of the Carbohydrate subsystem was the TCA Cycle followed by the significant presence of common functions involved in Glycolysis and Gluconeogenesis, Photorespiration (oxidative C2 cycle), Pentose phosphate pathway, Entner-Doudoroff Pathway, Trehalose Biosynthesis and CO2 uptake. There were distinctive differences between the metagenomes in the Carbohydrate subsystem (Fisher's exact test, q < 0.05). A significant number of sequences in the TP were associated with CO2 fixation and included CO2 uptake (carboxysome) and photorespiration (oxidative C2 cycle). Carboxysomes are microcompartments that enhance the fixation of CO2 by RuBisCO and are present in several chemoautotrophic bacteria, including sulfur bacteria, such as Thiobacillus denitrificansT. intermedia, and A. ferrooxidans[46]. Most of the BP sequences shared homologies to known genes involved in pyruvate:ferredoxin oxidoreductase, lactose utilization, β-glucoside metabolism, mixed acid fermentation, organic acids utilization (e.g. lactate) and sugar alcohols utilization (e.g. ethanolamine and propanediol). Based on the functional metabolic profile, the data suggest that the community present in the BP is predominantly composed of anaerobic or facultative aerobic bacteria with a wide variety of metabolic functions (Additional file 1, Figure S 1). A relative high number of sequences were associated with cell maintenance and structural functions such as cell division, cell wall and synthesis of DNA, RNA and proteins. Consistent with other environments, individual biochemical pathways (e.g. Nitrogen, Sulfur, Iron, Phosphorous and Potassium) comprised less than 1% of the functional genes profile [47,48]. Although functional similarities were observed, there were also relevant differences between the two biofilm samples. Most of the differences were attributed to the enrichment of specific gene families within metabolic pathways, some of which may indicate functional niches corresponding to varying microenvironments in the sewer pipes.
Sulfur metabolism
Analysis of metagenome libraries identified key genes implicated in the sulfur pathway (Figure 2). These functions were found to be abundant in the metagenomes, although we observed differences in the enrichment of specific gene families within the sulfur pathway. For example, in both metagenomes enzymes of three pathways involved in sulfur oxidation were detected: the Adenosine-5'-Phosphosulfate (EC 18.104.22.168, EC 22.214.171.124), the Sulfite:Cytochrome C oxidoreductase (EC 220.127.116.11) and the Sox enzyme complex (Figure 2). However, we found a relatively low odds ratio for the first pathway (<1.5), while the enzymes of the Sox complex that convert thiosulfate to sulfate were more statistically abundant and enriched (odds ratio >9) in the TP biofilm (Fisher's exact test, q < 0.05) (Table 2, Figure 2). Approximately 66% of the genomes in TP metagenome contained the soxB gene, a key gene of the periplasmic Sox enzyme complex [49] (Table 2). The widespread distribution of the Sox-complex among various phylogenetic groups of SOB was confirmed [50], specifically soxB-sequences affiliated with T. intermediaT. denitrificansT. thioparusAcidiphilium cryptum, and species of Burkholderia among others ( 1). The relative similar level of enrichment of the Adenosine-5'-Phosphosulfate pathway may be explained by the fact that key enzymes can be found in species of SRB and SOB, in which the latter can operate in the reverse direction [51,52]. In addition, the composition of species carrying the dsrB gene (sulfite reductase; EC 22.214.171.124) is noteworthy (Fisher's exact test, q < 0.05) (Figure 2 and Table 2). Retrieved dsrB-sequences for the TP biofilm show 80% of genes were closely related to T. denitrificans (SOB), while 78% in the BP were represented by SRB: Desulfobacter postgateiDesulfomicrobium baculatum, and species of Desulfovibrio among others ( 1).
Figure 2. Enrichment of enzymes in the sulfur metabolic pathway. Diagram with the enzyme classification (identified by their Enzyme Commission number; EC number) for each step in the sulfur pathway. Asterik (*) indicate components that are significantly different between the two samples (q < 0.05) based on the Fisher's exact test using corrected q-values (Storey's FDR multiple test correction approach) (Table 2). Bar chart shows the odds ratio values for each function. An odds ratio of 1 indicates that the community DNA has the same proportion of hits to a given category as the comparison data set [24]. Housekeeping genes: gyrAgyrBrecArpoA and rpoB. Error bars represent the standard error of the mean.
Table 2. Estimation (%) and enrichment of Sulfur and Nitrogen biochemical functional genes in wastewater genomes
The wide range of annotated functions associated in several sulfur pathways may be indicative of the availability of several electron donors at wastewater pipes undergoing corrosion. While the role of some bacterial groups might be predicted based on previous studies, our study suggests that additional bacterial groups might be playing important roles within wastewater concrete corrosion processes. This is the case for SRB as they are a phylogenetically diverse group that cannot be monitored using a single 16S rRNA gene assay ( 1). Our approach provides a sequence-based framework that can be used to monitor relevant microbial populations via function-specific assays. These assays can be used to measure the expression of key genes involved in corrosion processes, and hence be used to provide a condition assessment tool prior to corrosion processes that are irreversible.
Nitrogen metabolism
In spite of the importance of the nitrogen cycle in a wide range of habitats, the functional capabilities and distribution of their enzymes in wastewater systems, such as concrete biofilms, have not been fully explored. We identified key genes for nitrification, denitrification, nitrogen fixation and nitrate ammonification, including ammonia monooxygenase (amoA), nitrate reductase (narGnapAnasA), nitrite reductase (nirKnirS), nitric oxide reductase (nor), nitrous oxide reductase (nosZ), nitrogenase (nifHnifD) and assimilatory nitrite reductase (nrfAnirAnirB) in both metagenomes (Figure 3). Differences in the distribution and taxonomic assignment of key genes involved in the nitrogen cycle were observed in our analysis (Table 2 and 1). Specifically, amoAnarGnapAnirS and nrfA were highly enriched in the BP sample, while there was a higher distribution of the nasAnirK and nirB in the TP (Fisher's exact test, q < 0.05). The majority of the sequences in the BP sample were annotated to species of AcidovoraxThauera and Deltaproteobacteria (i.e. SRB), while most of the genes in the TP were associated with members of the T. intermediaT. denitrificans, and species of Burkholderia among others (Additional file 1, Figure S 1). Differences in the distribution and functional capability may be associated with the availability of oxygen and concentration of N compounds at each environment. Respiratory nitrate reductase (narG) reduces nitrate to nitrite predominantly during anaerobic growth, while the nasA assimilate nitrate during aerobic growth [53]. Furthermore, the enrichment of nirSnor, and nosZ suggest that the majority of the nitrite in the BP biofilm is reduced preferentially through the denitrification pathway (Figure 3). The nrfA enzyme is highly enriched at the BP biofilm (Fisher's exact test, q < 0.05) (Figure 3 and Table 2), supporting the observation that the nrfA enzyme is expressed when nitrate (or nitrite) is limiting in the environment [54]. On the other hand, we observed an enrichment of the nirB at the TP biofilm (Fisher's exact test, q < 0.05) (Figure 3 and Table 2), which is expressed only when nitrate or nitrite is in excess in the environment [54]. The enrichment of nitrification genes in the BP may be explained by the fact that domestic wastewater carry a substantial concentration of nitrogen compounds (20 to 70 mg/L), consisting of 60-70% NH3‒N and 30-40% organic N [55]. In fact, the gene encoding for ammonia monooxygenase (amoA), a key enzyme for ammonia oxidation was highly enriched in the BP metagenome (Fisher's exact test, q < 0.05) (Table 2). The metagenome data suggest that habitat prevailing conditions can select for bacterial populations with functionally equivalent yet ecologically nonredundant genes [56]. Specifically, we noted nirK is enriched in the TP while the nirS (nitrite reductase) is more prevalent in the BP biofilm (Fisher's exact test, q < 0.05).
Figure 3. Enrichment of enzymes in the nitrogen metabolic pathway. Diagram with the enzyme classification (identified by their Enzyme Commission number; EC number) for each step in the nitrogen pathway. Asterik (*) indicate components that are significantly different between the two samples (q < 0.05) based on the Fisher's exact test using corrected q-values (Storey's FDR multiple test correction approach) (Table 2). Bar chart shows the odds ratio values for each function. An odds ratio of 1 indicates that the community DNA has the same proportion of hits to a given category as the comparison data set [24]. Housekeeping genes: gyrAgyrBrecArpoA and rpoB. Error bars represent the standard error of the mean.
Functional diversity
We detected the presence of several types of adaptive responses to various heavy metal ions with the majority of the heavy metal-related functions enriched in the TP biofilms where the acid conditions are prevalent (Table 3). The majority of heavy metals become more soluble and mobile under low pH conditions [57]. It also appears that TP and BP biofilms are dominated by different types of uptake systems to control the intracellular concentration of heavy metal ions: (1) a fast, unspecific and constitutively expressed system and (2) an ATP hydrolysis-dependent slower yet highly specific system [58]. For example, the stand-alone arsB chemiosmotic transport protein (i.e. anion channel) is enriched in the TP biofilm (Fisher's exact test, q < 0.05), while the BP biofilm is rich in arsA enzymes (EC 22.214.171.124) (Fisher's exact test, q < 0.05), which transform the arsB into an arsAB ATPase complex [59]. The presence of heavy metal compounds provide the opportunity for selected individuals to oxidize these substrates and generate energy, as is the case of the presence of Thiomonas spp. with aoxB arsenite oxidase genes (EC 184.108.40.206) [60].
Table 3. Estimation (%) and enrichment of motility, stress, antibiotics and toxic resistance genes in wastewater genomes
A high number of genes associated with motility, stress response, antibiotic resistance, and virulence (e.g. efflux pump) were also identified in this study (Table 3). Motility and chemotaxis related functions seem to be important properties for submerged environments, such as the BP site, enabling bacteria to rapidly colonize surfaces through biofilm formation [61] and to respond to changes in environmental conditions characteristic of wastewater habitats [62]. In extreme and rapidly changing habitats, such as corroded concrete structures, microorganisms must respond with appropriate gene expression and protein activity [63]. We detected the enrichment of stress response components at the TP, which is characterized by the low pH of the surface and temporal changes in heavy metal ions due to corrosion (Table 3). Both biofilms have a high distribution of genes related to antibiotic resistance with a significant percentage of the genes incorporated in their genomes (Table 3). Furthermore, the wastewater biofilms contained an abundance of virulence-associated protein secretion systems, representing a reservoir for virulence genes. This may represent a conservative estimate of the number of potential virulence factors, since we only screened for a subset of genes homologous to type I, IV, V and VI secretion systems [64]. The significant number of resistance and virulence genes in their genomes and distribution based on odds-ratio (i.e. enrichment) analysis is consistent with the idea that sewage systems harbor favorable conditions for the establishment and propagation of antibiotic resistant bacteria [65].
Metagenomic data generated in this study enabled us to detect, identify and reconstruct metabolic pathways involved in MICC. The information generated from these sequencing libraries will help us better understand the genetic network and microbial members involved in wastewater biofilms. This information is also relevant to track microbial populations associated with concrete biofilms and to evaluate molecular assays used to detect key functional genes. In a recent study, Santo Domingo and colleagues [11] failed to detect the presence of ammonia oxidizing bacteria (AOB) on wastewater concrete biofilms using amoA-based PCR assays. These bacteria are expected to be associated with wastewater systems. In this study we were able to detect the presence of putative membrane-associated ammonia monooxygenase in the BP biofilm. The metagenomic sequences were highly homologous to sequences from heterotrophic representatives of the species Acidovorax delafieldiiThauera sp MZ1T and species of Rhizobiales (Additional file 1, Figure S 1). Heterotrophic ammonia oxidizing bacteria are commonly found in wastewater systems [66]. Ammonia oxidation by heterotrophic bacteria usually does not involve the generation of energy and is probably used as a sink for excess reducing power generated by oxidative metabolism [67]. Thus, the lack of previous detection of amoA genes by Santo Domingo et al.[11] can be explained by the fact that the assay cannot detect the amoA in heterotrophic ammonia oxidizing bacteria as they were designed to amplify representatives of the autotrophic ammonia monooxygenase, for example, Nitrosomonas species [68]. On the other hand, this study confirmed the validity of the soxB PCR-based assay to detect the presence of thiosulfate-oxidizing Sox enzyme complex in wastewater concrete [11]. A high percentage (>90%) of our metagenome sequences belong to species that contain the region for the Sox primers designed by Petri and colleagues [69], suggesting that they can be used to ascertain the presence of SOB in this environment.
In wastewater collection systems the sulfur and nitrogen pathways play an important role in MICC, and the populations engaged in these pathways are part of a complex and highly diverse microbial community [39]. The reconstruction of the sulfur metabolism network showed several pathways used to oxidize the end products of sulfate reduction leading to the production of H2SO4, e.g. Sox complex, sulfide quinone oxidoreductase (sqr) and the flavocytochrome c (fccAB) in the corroded section of the pipe (Figure 2). We detected similar levels of enrichment in both biofilms of the dsrB enzyme (Table 3). On the basis of these observations, and to better understand and control MICC, future investigations must consider the ability of these communities to: (1) utilize different sulfur compounds, e.g. thiosulfate (Sox complex) or sulfide (sqrfccAB), (2) adapt to temporal variation in the concentrations of sulfide, e.g. low sulfide (sqr) and high sulfide (fccAB), and (3) reverse the action of their enzymes, e.g. dsrB involves both the oxidative and the reductive mode of the dissimilatory sulfur metabolism. Sequences obtained in this study provide the molecular framework to detect the populations carrying relevant functions in future monitoring studies ( 1 and S 1).
Recently safe and cost-effective approaches to inhibit or prevent corrosion have included influencing the microbial population without the application of biocides by (1) supporting the establishment of competitive biofilms and (2) removing or adding electron acceptors such as nitrate [5,70]. The addition of nitrate can stimulate the growth of competing bacterial populations (e.g. nitrate-reducing bacteria), which can effectively displace the SRB [71]. The success of these approaches must include a detailed analysis of the established bacterial populations and functional capabilities of the microbial community in that particular system. In fact, our data provide evidence of the effect of habitat selective factors on microorganisms and consequently their functional capabilities. For example, the diversity of the denitrification genes nirK and nirS increased in habitats with relatively moderate and low levels of nitrate/nitrite, respectively [72]. Other corrosion control approaches include commercially available coating techniques, for which limited data is available on their performance. The data from this study identified the potential bacterial groups and specific gene sequences that remediation approaches need to target to prevent microbial colonization of key concrete corrosion-associated microbiota.
In the present work, we analyzed wastewater concrete metagenomic and phylogenetic sequences in an effort to better understand the composition and function potential of concrete biofilms. The analyses unveiled novel insights on the molecular ecology and genetic function potential of concrete biofilms. These communities are highly diverse and harbor complex genetic networks, mostly composed of bacteria, although archaeal and viral (e.g., phages) sequences were identified as well. In particular, we provided insights on the bacterial populations associated with the sulfur and nitrogen cycle, which may be directly or indirectly implicated in concrete corrosion. By identifying gene sequences associated with them, their potential role in the corrosion of concrete can be further studied using multiple genetic assays. The development of comprehensive databases such as the one generated in this study as well as for microbial communities in wastewater systems with a wide range of corrosion conditions will be useful in the development of tools in diagnosing and preventing MICC. Although the emphasis of this study was on corrosion processes, we also identified the presence of bacterial virulence factors and antibiotic resistance genes, suggesting that these systems are reservoirs of microbial populations of public health relevance.
Authors' contributions
VGA participated in bioinformatic and statistical analyses. RPR and JSD carried out sample collection and sample processing. RPR and JSD participated in design and coordination of the study. JSD conceived of the study. All authors helped to draft and revise the manuscript. All authors read and approved the final manuscript.
We thank Jarissa Garcia, John Sullivan, and James Weast of the Metropolitan Sewer District of Greater Cincinnati for the technical support provided during the collection of samples, to Dan Murray (USEPA) for discussions on concrete corrosion, to Brandon Iker for laboratory technical support, and to Robin Matlib for bioinformatics support. This manuscript was approved for publication by the United States Environmental Protection Agency (USEPA). Any opinions expressed in this manuscript are of the authors and do not necessarily reflect the official positions and policies of USEPA. Any mention of products or trade names does not constitute endorsement or recommendation for use.
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Window zooming on Mac is different. It will try and analyse the app or webpage you are on and maximise so there is no white or blank space. It seems clever, but I do like to have some apps full screen, just to minimise eye strain and distractions.
That's interesting. At least there is a method to the madness. I'm not so sure that it works correctly as some sites and programs will just stretch and fill the screen accordingly. Like this site when I full screen I can turn a block of text into 2 lines. It becomes a lot easier to read because you won't lose your place in the wall of text.
@Six: For apps I would love to have inssider as all of the wifi detection programs I've seen are so so. (would be equally great on a tablet) Fraps would be another obvious tool that works great on the desktop, and could be pretty useful if it would work out of the box on the phone. Openvpn, paint .net, teamspeak, vmware client.
I'm actually kind of interested in the Asus tablet that was x86 based. That could be a killer product if it was at the right price point. It would be like having a netbook that was actually powerful, yet the keyboard detached for tablet usage. On top of that having a touch screen with metro UI would make it a lot easier to use than a netbook because the touchscreen would work a lot better than the cheap touchpads do. No need to wait for a specific app to show up as you could just run all of your favorite programs.
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Hospital workers/scrub pants carry?
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Fanny Pack is the best but only for a small handgun like a KelTec .380, or a bodyguard .38. You can never take your fanny pack off at work, never! You may also wish to read all the Hospital policy book that is supposed to be available, as often it is buried in a policy.
Ankle holsters do not work , neither do belly bands. If you have a small fanny pack people do not suspect you might be packing. Getting caught with a CCW is a fireing offence in almost every case. Don't ever tell anyone that you carry.
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text:
Stoutland will be Miami interim coach for bowl
CORAL GABLES, Fla. Miami offensive line coach Jeff Stoutland has accepted an offer to be the Hurricanes' interim coach, taking over less than one day after the university fired Randy Shannon.
Stoutland held early strategy sessions with other assistants, all of whom have been told they are welcome to stay through Miami's bowl game, although some may consider leaving if they secure other offers. Players were told of the decision by athletic director Kirby Hocutt and other coaches in a Sunday morning meeting that turned emotional.
Hocutt was scheduled to hold a news conference at 1 p.m, but the university confirmed Stoutland's new title.
"I'm very disappointed," quarterback Jacory Harris said. "Coach Shannon is like my father figure. He's someone who brought me into this program and I wanted to leave with Coach Shannon still being my head coach, but it's an unfortunate situation that we have to go through. It's something that I'm sure a lot of people are mad at, especially on this team."
Hocutt fired Shannon on Saturday night after the Hurricanes completed a 7-5 regular season with a 23-20 overtime loss to South Florida. Shannon received a four-year extension just before the start of the 2010 season. He was 28-22 in four seasons at Miami, with Stoutland as his offensive line coach throughout that tenure.
"Surprised wouldn't be the word. I was a little shocked about it," defensive lineman Adewale Ojomo said. "But you could almost see it coming."
Miami players are not scheduled to practice again until Saturday, though that may change. The Hurricanes expect to have a bowl destination, possibly the Sun Bowl, by week's end.
"We have made a decision to seek new leadership for our football program," Hocutt said in a statement Saturday night. "Our expectations are to compete for championships and return to the top of the college football world."
Since the start of the 2007 season, 47 teams have more wins than Miami - including four from the state of Florida. The Hurricanes were 16-16 in the ACC under Shannon, the sixth-best mark in the 12-team league. And barring a wild turn of events, Miami will finish out of the Top 25 for the fourth time in five years.
The truest consistency was inconsistency.
Miami's longest winning streak under Shannon was five games during 2008, and three of those victories came against teams that finished the year with losing records. The Hurricanes went 1-7 away from home against ranked teams since the start of 2007. The only win over a top-10 team was last season, when Miami beat Oklahoma - a game Sam Bradford sat out with a shoulder injury.
Hocutt made the decision shortly after Miami lost to South Florida in a game where about 27,000 people filled the 73,000 seats at Sun Life Stadium. A plane circled the stadium before kickoff calling for a coaching change.
Shannon drove away from the stadium around 5:30 p.m. Saturday unsure of his fate, though he suspected that he would be fired after the Hurricanes were embarrassed at home by Florida State on Oct. 9 and then were beaten by lowly Virginia three weeks later. He considered making many changes to his staff and was deciding whether to dismiss some coaches later Saturday evening.


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About Schools in Mayfield, UT
Contact a Coldwell Banker® real estate agent to learn more about the schools and school districts in Mayfield, UT.FIND AN AGENT
Mayfield, Utah is located in Sanpete County. Nearby cities and towns include Sterling, Centerfield, Gunnison, Fayette, Manti, Redmond, Salina, Ephraim, Aurora, Scipio, and Sigurd. Mayfield is a rural community with a population of 513. The median household income is $38,124. In Mayfield, 62% of residents are married, and families with children reside in 36% of the households. Half the population of Mayfield commutes 14 minutes or less to work, with 60% of residents holding white collar jobs and 40% residents holding blue collar jobs. The median age of homes in Mayfield, UT is 29 years, with 63% of those homes owned, 11% rented, and 26% not occupied.
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Director: Brett Ratner
Cast: Dwayne 'The Rock' Johnson, Rufus Sewell, Ian McShane, John Hurt, Joseph Fiennes
Rating: ***
What's it about: A retelling of the myth of Hercules, the Greek hero. Here, the demigod has lost it all - family, country and peace of mind. With nothing else left to lose, he lives and fights with his band of fearless mercenaries, eager for a fight and for gold. While there's nothing heroic about this guy except his legend, he takes on the onus of training an army to do battle against a rebellious warlord.
What's hot: McShane as the seer Amphiaraus is brilliant in a role that he completely inhabits. Hurt as Lord Cotys is pure menace even when he's pretending to be the long-suffering king of Thrace. And it does help that Johnson is sincere to the script to a fault. He looks like he can win wars by himself. The story has its moments, but you tire of waiting for them. The saving grace are the one-liners and the fight scenes.
What's not: Several things, actually. Ever hear that line... if it ain't broke, don't fix it? Well, it was said for a reason. When we meet Hercules, he bleeds and he has nightmares. Making the greatest Greek hero of all, simply an incredibly strong human being is quite simply, trying something that while brave, didn't need that treatment. Also, this feels like The Last Samurai-meets-Gladiator. So really, how original was this intended to be, Mr Ratner? And the abundance of accents! Couldn't they just have stuck with one? And the whole thing seems like it was completed in an incredible hurry.
What to do: With two Hercules films already out this year, this one comes off too little, too late despite being a far superior effort than the other two. Could've been so much better. Watchable, but not repeat-worthy.


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23X 700TVL PTZ Security Camera
Product# PTZ-EL700L23X
20X 2 Megapixel Infrared IP Network PTZ Security Camera
Product# IPPTZ-EL2MPIR250L20X
Price $1,214.65
Usually Ships Same Day
Customer Reviews
23X 700TVL PTZ Security Camera
We ordered this camera on the weekend and received it at the office before the following weekend. Great shipping response, camera was packed well and had no apparent damage from shipping as well. The camera provides a pretty astounding clear video picture for 600/TVL/700TVL. The 23X zoom does a a good job as well. Another nice feature about this camera is it's light sensitivity. The camera does extremely well at night, especially if there are street lights, store fronts, or lit store signs in the vicinity.
We also like the Security Camera King intelligent 3-D positioning. Right out of the box, the camera protocol is ready at Pelco-D AND DH-SD. The DH-SD has a slightly different menu system then Pelco-D and it is what allows you to use the intelligent positioning function with a Security Camera King DVR. The difference is that instead of clicking on a menu of a directional button, all you have to do is click and drag downward to create a rectangle. Instantly, the camera moves to that area and zooms in. The more you do this, the more the camera continues to zoom in on and center the area. Reversing your click and drag motion with the mouse, that is clicking and dragging upward on the screen causes the camera to zoom out or widen the field of view. We do a lot of manual PTZ movement with our camera and our old one used a PTZ joystick controller. This is much, much easier, quicker and efficient. The only negative aspect of this is that the DVR needs to be in the vicinity of the monitor and you need to be there too to use the mouse. It still works great though, easy to mount, good performance, quick and accurate movements.
23X 700TVL PTZ Security Camera
1 of 1 people found this posting helpful
I am very impressed with our PTZ-EL700L23X ZPTZ camera. The camera captures a good quality video and is very responsive in it's Pan, Tilt, and Zoom movements. In fact the movements are actually quicker than I expected, maybe not exactly a "speed dome" per se but close. The low light sensitivity is appropriate for a PTZ camera with no on-board infrared illuminators. Although the color low light sensitivity is only what I would consider moderate at 0.1 lux, the black and white mode is incredible with a rating of 0.0002 lux. The camera has a full complement of presets, patterns, tours, etc. In addition, we use this camera with our Security Camera King Ultimate Series DVR and have no need for a separate joystick controller for the PTZ because we can simply control the camera using the USB mouse and the monitoring screen. The wall mount being included is also another nice touch, considering that some vendors will charge up to $70 or more for a wall mount. In addition, the camera has a small braided wire safety cable to keep it from crashing to the ground during installation or configuration. I have can easily rate this camera based on performance and features compared to cost at five stars with good conscience.
Nice Working PTZ!
2 of 2 people found this posting helpful
Love this camera! It's true that if you really want to get the most out of it, use it with a Security Camera King DVR. I actually have to say that I enjoy using this camera. Between the DVR synchronization and the 3D intelligent mouse positioning you can easily move and use the camera any way you want. The Sony Super HAD II CCD and the Enhanced Effio-E digital signal processor are a proven quality combination in video security cameras as I have installed many cameras with this sensor/chipset combination and the video is just as clear and defined as can be expected for the rated resolution. This PTZ has great low light sensitivity especially in black and white mode (most often used at night) as it is rated at an outrageous 0.0002 lux in black and white. Even the color sensitivity is good with a 0.1 lux rating. The 23X zoom lens is quick and clear. The camera has all the "goodies" you need for a PTZ and can be used outside in cold climates as well with its built in heater/blower. I have installed a few of these and haven't had any dissatisfied customers yet. Moreover, Security Camera King has an almost unrealistic technical support team. These guys are willing to answer any question and solve any problem you have that is within their scope. They are polite and a refreshing bunch of people to talk to and they know their equipment.
23X 700TVL PTZ Security Camera
3 of 3 people found this posting helpful
This is what I would call a good upper-middle class PTZ camera. The camera records well and produces a clear color or black and white video. The resolution of the camera is 600TVL in color and 700TVL in black and white. I call it a good "upper-middle class" camera because even though the video is high quality, the color side still has room for improvement on resolution (from 600 to 700TVL) and the PTZ movements of the camera are not exactly what I would call a high-speed PTZ but they are about in the middle. The movements are easily controlled via typical methods and when the camera does Pan, Tilt, or Zoom, it does so accurately and without any excessive vibration. The 23X optical zoom lens does a nice job of zooming in on objects far away to make them clearer as well as objects closer in to see more detail. According to Security Camera King, the rating on the light sensitivity of this camera in black and white mode is amazing at 0.0002 Lux and not bad at all in color at 0.1 lux. Although I do not have a light meter, I can say from experience that the camera does well outside at night without any exterior infrared illumination. The "Upper" side of my description comes from the great low light sensitivity and the advanced On Screen Display (OSD) menu system of the camera. There are plenty of features with various settings to adapt the camera to different environmental conditions. I like the camera, I haven't had any problems with it, and yes, I would recommend it to others if they asked.
23X 700TVL PTZ Security Camera--Good Auto Tracker
3 of 3 people found this posting helpful
This is a quick and reliable auto tracking PTZ. The cost obviously reflects the auto tracking feature and the true day/night camera feature as the resolution isn't all that high (520TVL) in this day and age of megapixel cameras and 700TVL resolution cameras being common. Since it auto tracks (and the 27X zoom is great too) it also has automatic focus. The auto-focus works very well with over compensating one way or the other. I've seen some other manufacturers' PTZs with auto focus where the darn lens goes too long then backs up too short before settling on where it should be giving you a sensation like your vision is going, but this camera does not do that. Of course, Security Camera King is a reliable dealer and sells genuinely high quality products and that is reflected in this particular item by the fact that the camera is actually a Veilux, which is one of the best camera manufacturers in the US if not the world. The camera works pretty well in low light--as long as you have some available ambient light you'll probably acquire a decent picture. There are about 16 DIP switches on the bottom of the camera but don't let them shy you away (I'm talking to DIYers) as they aren't as much to deal with as they may seem. Overall this is a nice auto tracker with a good zoom.
23X 700 TVL PTZ Security Camera
3 of 3 people found this posting helpful
I like this camera for several reasons. First the 23X power zoom is optical not digital so it is a true zoom and it really brings thing in closer. Second, this is a very light sensitive camera; no infrared LEDs here so the night time range isn't necessarily limited by the range of any on board LEDs or external illuminators. The camera is quick to respond, stable, and has a lot of features.
Security Camera King 23X 700TVL PTZ Security Camera
4 of 4 people found this posting helpful
I'd like to find something to complain about with this camera but I really can't. The price is reasonable and the quality is super. The resolution is 600TVL color and 700 TVL black and white. The zoom is 23X optical and 10X digital for a total possible zoom power factor of 230X. I guess if I were to suggest any improvements I would recommend a 700TVL color resolution and a greater power zoom, but of course I'm sure that would dictate and increased price tag. The video capture of this camera is very high quality and is very sharp and concise. The camera's OSD is loaded with a whole lot of menu pages that allow you to adjust settings and features on the camera, some of which you'll definitely want to use and some you never will. The camera housing and body is connected to the mount with a small diameter wire wrapped safety cable to help keep you from accidentally dropping it when servicing it (it's about time someone did that! If you don't know why I say that, try dropping your own from about 25 feet up above a slab of concrete and see how it survives).
This PTZ also boasts Security Camera Kings "3D Intelligent" positioning function. What this means is that first of all, you no longer have to use a separate joystick controller board to operate the PTZ. It can be activated and controlled directly from the DVR. Even more so, you can use the Security Camera King DVR with a USB mouse to control the camera! All you do is point, click and drag with the mouse and the camera knows what to do and performs the proper control movements to give you the best picture. Smart, I guess that's why they call it "intelligent."
23X 700 TVL Security Camera Made for Security Camera King DVRs!
3 of 3 people found this posting helpful
This is definitely a "made for Security Camera King DVR" kind of camera! I really like the 3D position control that it is capable of by just using the mouse to control the PTZ movements. It eliminates the need for a cumbersome joystick/keyboard panel and if someone can't operate this camera using a mouse, I really don't think they could do any better with a joystick controller. The 23X power zoom is a treat on this camera bringing everything closer and making it larger and easier to see and identify. The video captured is of very good quality especially with the color resolution being 600TVL and black and white at 700TVL. I also think the Sony Super HAD II CCD with the Effios-s digital signal processor makes for a good combination for a PTZ camera. Light sensitivity varies greatly depending on what mode you are recording in. In color, this chipset is rated for 0.1 Lux which isn't tremendous but isn't bad. But hold on to your flashlights in black and white because the sensitivity bumps up (or should I say "down) to 0.0002 Lux giving you incredible power for night time shots with a long distance zoom. The camera comes with its own temperature control so it stays thawed out up here in our cold winter climate. Our Security Camera King Ultimate security system is basically a 12 VDC system so I thought that might be a problem since this camera operates on 24 VAC but it comes with its own power supply so there isn't much worry there. PTZ response and movement times are pretty quick and the camera responds quickly to the mouse controls as well.
23X 700TVL PTZ Security Camera
2 of 2 people found this posting helpful
This is a high quality PTZ with what I would call a middle of the road zoom power. It's pretty powerful on the zooming, but the magnification power isn't so high that the camera is going to cost you $1500 but it's not to low too be virtually unnoticeable either. Our company uses this camera in its security camera system for outside surveillance of our building and parking lot and it works very well. The camera can hold its own in low light conditions as well, especially when you switch from color to the black and white mode. (It's rated at 0.1 LUX in color and 0.0002 LUX in black and white). Our parking lot is always lighted at night so it isn't even an issue for us. We can get some fairly challenging Winter weather here and the camera operates well under cold conditions (like the Winter we just had) here. It has a built in heater fan that runs continuously to keep things from freezing up inside. We do own a Security Camera King Ultimate series DVR and this camera works very well with it. The 3D mouse oriented controlling works very well. (You just point and click on your monitor screen where you want the camera to tilt or pan to and it goes there. Drag a rectangle around an area and the camera goes there and zooms in. It's nice if you like the idea of eliminating a PTZ joystick controller. On the other hand, if you prefer the joystick you may not care for this feature but you can still use the controller too.) I like the idea of the safety cable that keeps the camera module connected to the mount when servicing. It's a nice touch to help prevent a $600 camera from smashing to the pavement when you are working on it.
23X 700TVL PTZ Security Camera
4 of 4 people found this posting helpful
As a CCTV technician and independent contractor I'm always happy when I can get a camera with the Sony Super HAD II Effio DSP chip combination, let alone when I can get it in a PTZ because I know the quality of the video is going to be great. This PTZ has a color resolution of 600 TVL and a black and white resolution of 700 TVL. It also has a pretty high quality optical stack as far as the 23X zoom lens is concerned so it provides a nice, clear, detailed video without any flaws. I've had no problems at all with mounting and the camera includes a built in heater and fan since it is rated at IP67 for outdoor use and it includes 4000V lightning and surge protection. My customers like this type of PTZ especially when they purchase or already own Security Camera King DVRs because they can use the 3D intelligent positioning which can virtually eliminate the need for a joystick controller. Basically, all you have to do is pint and click the mouse to move the camera or click and drag the mouse to form a rectangle and the camera will move to that location and zoom in automatically. When it comes to following objects, especially people, this 3D intelligent positioning makes it very easy. It's got a pretty good handle on true day/night vision too with the color mode rated at a minimum of only 0.1 LUX of light needed and the black and white mode at a whopping 0.0002 LUX! As far as the other electronic features you'd expect, they are all there. From an installers perspective I also like the metal wound safety wire or cable that is clipped to the camera body and mount. It helps keeps you from dropping a $500+ camera and smashing it to pieces on the ground or floor below while you are making adjustments and performing the installation.
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Blue Polywire - 1,312'$38.95 As low as: $35.06This Polywire is for permanent or temporary installations and provides an excellent high level of conductivity that allows for the use of high and low powered battery energizers. Learn More
Earn 38 Points
Yellow/Black Polywire - 1,312'$25.45 As low as: $22.91Black and Yellow Polywire has 3 stainless steel wires. This Polywire is an excellent conductor and perfect for temporary fence or controlled grazing. It is very easy to re-spool and has a UV inhibitor added to extend its life. Learn More
Earn 25 Points


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Memorial Day Weekend at Hall-Fawcett Park
The Ohio Association of Garden Clubs in Logan County (DeGraff Garden Club and Fleurette Garden Club) invite the community to attend their annual spring plant sale on Saturday, May 23rd from 9 a.m. until 12 p.m. The sale will be held in front of Big Lots at 1760 South Main Street in Bellefontaine.
The Logan County Garden Clubs region 5 (O.A.G.C) want to invite you and your friends to our yearly Plant Sale in front of Big Lott's at 1760 S. Main Street (Fountaine Shoppin Center)
Spaghetti Supper & Dinner Auction
Saturday, May 23, 2015
5:00pm to 7:00pm
East Liberty Lodge Hall
Menu includes for a donation: Spaghetti, salad, garlic bread & drink
Come and bid on some wonderful desserts prepared by some of our local bakers! Silent dessert auction bidding will end promptly at 6:30pm
Event sponsored by the Perry Township Events Committee
Proceeds benefit our 2015 Independence Day Celebration
Please call 937-666-3974 for more information.


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My two nephrologists (partners) are in disagreement about whether or not I should be on both medications. One prescribed linsopril with furosemide, along with continuing the losartan. The second told me to stop the linsopril because it increases my risk of a heart attack. I have primary edema now and the first doctor believes that the combination linsopril and lasix will reduce my swelling and decrease the protein in my urine. I am scared and confused about this disagreement and don't know what to do. I especially feel put in the middle. I have uncontrolled hypertension.
Is linsopril and cozaar taken together inherently dangerous for me?
- Posted:
- 29 Apr 2012 by MitchieMay
- Topics:
- cozaar, high blood pressure, diabetic kidney disease, furosemide, losartan, edema, medication
Answers (1)
I also take both and I have no problems with either one, although my nephrologist want's me to occasionally skip a dosage of the furosemide so I don't "fry out" too much.
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Brett Whiteley Studio
2 Raper Street, Sydney, NSW 2010Map
+61 2 9225 1881
Neighborhood: Surry Hills
Brett Whiteley was arguably Australia's most famous contemporary artist before his tragic death in 1992. He is best known for his stunning views of Sydney Harbor, sensuous female nudes and self-portraits. In 1985, he converted a former T-shirt factory into a studio and residence. This is now administered as a public museum by the Art Gallery of New South Wales, and showcases examples of Whiteley's work together with personal effects and memorabilia. The museum also mounts regular thematic exhibitions on Whiteley and other artists.
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Sheriff: Neglected Animals Seized From Meeker County Home
Authorities said at least six horses and nine dogs were seized from their owner in south central Minnesota Wednesday night after it was determined they were suffering from neglect. The Meeker County Sheriff's Office had been out to the home on the 24000 block of County State Aid Highway 14 in Darwin, which is in Meeker County just west of Dassel, on a report that some horses had gotten loose.
Best Places For Horseback Riding In Minnesota
Plan a fun horseback riding outing with the family at any of these great stables near the Twin Cities.
After Decade Slump, Horse Breeding & Racing On The Rise
It's a big night for racing in the Twin Cities, as the horses at Canterbury park are ready for the start of the racing season. It's not just the jockeys and trainers who have something to be excited about.
A Selfless Teen's Gift Gives 2-Year-Old Hope
The help of a stranger is bringing a 2-year-old girl with cerebral palsy closer to one day walking. That stranger is 17-year-old named Allie Kanyetzny, a high school girl with a very big heart.
Minn. Farmer 'Shocked' After Horses Put Down By State Patrol
The Minnesota State Patrol had to put down two horses after they got away from their Faribault farm early Monday morning. They'd been trying to get the horses back onto their property when they say the situation just became too unsafe. But, as can be imagined, the horses' owner is very upset.
Can't Bet On The Derby At Running Aces
For the first year, Canterbury Park in Shakopee has exclusive Minnesota rights to Kentucky Derby bidding. That means Running Aces is shut out of one of racing's biggest days.
494 Crash Spills 3 Horses Out Of Trailer
If you think you saw horses on the side of the highway last night, you're right.
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Nearly 70 Horses Seized Due To Neglect In SD
The Pennington County Sheriff's Office has started a criminal investigation after nearly 70 horses were impounded for neglect.
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A southeastern Minnesota man has been charged with 25 animal cruelty counts and one of improper disposal of carcasses after authorities seized 55 horses from his farm.
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'U Of M' Hospital Nurses Horses Back To Health
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