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Located in the southern part of Peru, Arequipa is the country's second largest city with 1 million inhabitants. It's a bustling metropolis with a large and vibrant Spanish colonial quarter at its heart. It's actually a UNESCO World Heritage site thanks to this beautiful architecture and the city's efforts at preserving these links to the past. The historic buildings are made of a white-colored local volcanic rock called sillar, giving the city its nickname: the White City.
Arequipa has a lot going for it and as a result it's becoming an increasingly popular destination for travelers. Many head to the nearby Colca Canyon, one of the world's deepest, to see endangered condors; others go to experience authentic indigenous culture and the natural splendor of Lake Titicaca.
But Arequipa also has plenty of conveniences and advantages that attract retirees and other expats.
The weather is beautiful, just about perfect. Count on 300 sunny days a year and a year-round temperate climate—in the 70s during the day, cooling off into the low 60s at night. It's the perfect place to enjoy the outdoors, whether strolling down a city street or enjoying a coffee on your terrace.
The cost of living is low. Three-bedroom apartments in the most desirable neighborhoods near the historic quarter start at $400 for rentals. Utility costs are also reasonable: electricity costs $50 to $60 per month, water is $10 per month, and internet/cable TV is $70. For meals, plan on paying $2 to $3 for a local meal, $10 for something in a high-end or international restaurant.
There are plenty of modern conveniences. Large grocery stores carry imported and gourmet foods, and there are shopping malls where you can get any product you need.
All that and the scenery and architecture is breathtaking. The mountains and volcanoes that surround the city provide a dramatic backdrop to the grand cathedrals, churches, and homes in the colonial area.
Arequipa is just an hour flight from Lima, but world's apart. Arequipa and Lima actually have a long-time rivalry, with many Arequipa residents considering themselves arequipeño first and Peruvian second. But in any case, the people are very friendly and welcoming of foreigners. And, thanks to the influence of tourism, many speak English.
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It's perfect for summer weddings
Think rainbow-coloured ruffles and ayurvedic-inspired dresses
From what to buy right now, hot new designers, to front row fashion week reports, get the latest fashion and shopping news with daily updates from the Red fashion team.
It's the perfect dress to ease us into spring
Meghan wore the khaki number on her tour of South Africa
It's part of a capsule collection which launched today
Finding something to wear to that spring wedding just got easier
It's available in gold and silver
We love the statement colour!
One of the Duchess' most risqué looks to date
It will go with everything in your winter wardrobe!
But you'll have to be quick!
They will literally go with everything
Did we mention that it's only £50?
The new polka-dot print is perfect for autumn/winter.
Just because you aren't French doesn't mean you can't dress like you are
It's the perfect dress for autumn
Turns out they do have a purpose

subset: commoncrawl


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123do: Creation of a cube with and without collision box
One-Two-3DO (also known as 123do)
One-Two-3DO or in short 123do let's you create 3DO objects for GPL. You can get it here: [Link to One-Two-3DO].
It runs fine here for me with Windows Vista 64 bit with an Nvidia 8800GTS. Only thing which had to be changed is to "Disable desktop composition for the OneTwo3DO.exe like you can see in this screenshot
When you start 123do you will see a window like this:
Now you must understand that you need points (vertices) to attach polygons and lines on them.
The unit measurement 123DO used is in metres. Thanks to Ginetto here's a translation formula:
1 metre = 3.28083 feet = 39.36996 inches
Let's create a simple 3DO cube
Background vertices
First, here's a generic picture of the 3D room and how the vertices are positioned for a cube. This picture shall tell you a bit about the positioning of vertices in GPL.
I have numbered the vertics we need for a cube from 0 to 7. Like a real cube the cube in 3DO has 8 corners. You may ask yourself why I start counting the vertices at 0. 123do and GPL use a different approach for counting. The first element is 0 instead of 1 we're using outside in the real world.
If I want to create a 3DO cube with a dimension of 1 metre for every side of the cube I need to create those 8 vertics:
vertics index x y z 0 1 0 0 1 1 1 0 2 0 1 0 3 0 0 0 4 1 0 1 5 1 1 1 6 0 1 1 7 0 0 1
You need those vertics as points for polygons or lines. Without those vertics you can not assign a polygon or a line to it.
Here's a picture to display an idea how it works for a simple polygon:
The edges of the polygon are attached to the vertices.
Adding vertices
Now this should be enough for the basics of vertices and polygons. Let's get back to the open 123do program and transfer what you have read above to the real cube.
To add the vertics to 123do open the Create/Add vertices manually from here:
You should then see this window, showing you defined vertices on the left side and the possibilities to add/edit/remove vertices on the right. I have filled in the values of vertic 0. Remember from the background section Background about vertices the matrix about the 8 needed vertices.
Now in the next image you see I have filled in all needed vertices for our test cube.
Close the dialog and choose File/Save project. Make it easy and give it the name of the 3DO you wish to have. Please use 8.3 syntax naming the project. In my example I use cube like you can see from the attached picture:
Adding Textures
Now it's time to think about the cube, vertices, polygones and what we will see in GPL. To the cube in GPL it needs to have some bitmaps painted on the sides. You recall that the sides are build out of polygons.
Adding Polygons
Untextured first
Now we come to the hardest part of it. We need to add the polygons. When adding the polygons, the sequenz how you add the vertics will be critical from where your polygon will display an attached texture (bmp in 123do and as a mip in GPL).
If we add the vertices 0,1,2,3 in that sequenz you can see from the picture above that this is the bottom of the cube. Imagine watching from the bottom:
0,1,2,3 would be clockwise. This would result in a plane pointing in your direction which would mean that you can see the image. 3,2,1,0 would be anti-clockwise. This would result in a plane pointing away from you which would mean that you can't see the image.
Please select the Create Polygons button:
I have filled in the values for this polygon as well as the values for the remaining 5 polygons.


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Costa Coffee, Kenco, Mars Honored by Rainforest Alliance
Costa Coffee, Kenco, Mars Honored by Rainforest Alliance
UK chain Costa Coffee, the Kenco Coffee Company and Mars Inc. are among the companies and organizations who have been named Sustainability Standard-Setters this year by the Rainforest Alliance.
The nonprofit organization holds it annual Sustainability Standard-Setter award ceremony tomorrow and released the list of award winners today. The group strives to preserve rainforests, conserve biodiversity and foster sustainable livelihoods through responsible land-use and business practices and consumer behavior.
The 2011 Sustainability Standard-Setter honorees are:
- Costa Coffee, the largest and fastest-growing coffee chain in the United Kingdom, has committed to sourcing all of its beans from Rainforest Alliance Certified farms.
- The Kenco Coffee Company, now a Kraft UK brand, also is working to source 100 percent of its coffee from Rainforest Alliance Certified farms. The company recently began selling coffee in Eco Refill packs that cut the packaging weight for each pound of coffee by 97 percent, compared to standard packaging.
- Mars Inc. is pursuing sustainability of its raw ingredients, including the cocoa used in its chocolate products. By 2020, Mars plans to source 100 percent of its cocoa from sustainable origins, including Rainforest Alliance Certified farms.
- Mexico's Ministry of the Environment and Natural Resources -- National Forestry Commission.
- Eric Poncon, a business leader with long ties to sustainable coffee, forestry and tourism.
- The nonprofit group Mayan Palms.
- The Mayakoba Tourism Development in Mexico and the three hotels that comprise it: the Fairmont Mayakoba, Rosewood Mayakoba and Banyan Tree Mayakoba.
More information on the award winners and the Rainforest Alliance are available at rainforest-alliance.org. This year's awards will be conferred at a gala whose co-chairs include celebrities Sigourney Weaver, Martha Stewart, Jane Alexander and Mary Stuart Masterson.
Credits for photo illustration elements: Image of Sustainability Standard-Setter Award by Silk Studio Inc. and Rainforest Alliance certification logo both via rainforest-alliance.org.


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Northwood by Brian Falkner
(Adventure/Fantasy) Cecelia Undergarment is a courageous girl. When she discovers a neighbour's dog needs her help she hatches a plan. Unfortunately her plan didn't involve the place she finds herself, Northwood Forest, a dark and mysterious place from which no one has ever returned.
(Book trailer HERE)
An Elephant in the Garden by Michael Morpurgo
(Historical-WWII) Lizzie's father is fighting in the war, her mother works at Dresden Zoo. To save a zoo elephant Lizzie's mum brings it home to live in their backyard. But when the bombing starts it's not safe there either and the family and elephant must leave to find somewhere safe to stay.
The Strange Case of Origami Yoda series by Tom Angleberger
(Humorous stories) Tommy's friend Dwight does some weird things, but he does one cool thing - origami. One day he makes a Yoda finger puppet, and Yoda gives great advice that really works. Tommy wants to know how Yoda can be so smart when Dwight really isn't smart. Is Yoda using The Force?
(Book trailer HERE)
The Secret Garden by Frances Hodgson Burnett
(Historical/Children's Classic) Orphaned Mary is sure she won't like living at her uncle's estate until she finds a secret garden, locked and forgotten since the death of her aunt. Mary starts working on the garden to restore it to its former glory. When she finds she has a young invalid cousin living in the house she hopes the secret garden will work its magic on him too.
Grimsdon by Deborah Abela
(Science fiction/Adventure) When the sea surged into Grimsdon three years ago many were rescued, some were lost. Those left behind inhabit the floors of buildings which still rise above the water. Isabella, Griffen and friends survive by scavenging, hiding from bounty hunters & making deals. But these aren't their only worries, they also fear the monster of the deep!
(Book trailer HERE)


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It is currently Thu Apr 02, 2020 3:01 am
Casualty and theft losses are miscellaneous itemized deductions that are reported on IRS Form 4684, which carries over to the Schedule A, then to the 1040 form. Therefore, in order for any casualty or theft loss to be deductible, the taxpayer must be able to itemize deductions. If this is not possible, then no loss can be claimed.
For the monetary loss, I don't think we can get it back. However, we can deduct certain amount (losses -100- 10%*AGI) in us tax return. You can find details at IRS link http://www.irs.gov/taxtopics/tc515.html" onclick="window.open(this.href);return false;
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text: Brothers disclosing when they've been sexually assaulted is an unintended, but welcome, consequence of the #METOO campaign. In the 1970s, at the D.C. Rape Crisis Center, we counseled many African American men and boys who had been sexually assaulted by other men and boys. Prisoners Against Rape was started because the men who raped women outside of prisons, raped men inside. That was when i first heard Black men began speaking out against their own sexual injustices, but only rarely is the conversation broadened so that more brothers participate. I believe homophobia and transphobia prohibits more men and boys from speaking out. Where's the Black Men Against Rape movement?


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Deep ruminations, random thoughts . . . C'mon it's a blog what did you expect?
Saturday, May 10, 2008
Tradition vs. Text
Check out this previous post for some context.
It seemed to be the consensus of the majority of the commenters on my previous post that when faced with biblical texts that lack good historical evidence we use tradition to determine whether or not it should be used in the work of the church.
Guess what, you're all Catholics! Ok, maybe not totally, Catholic, but a little bit.
The Protestant Reformation of the 16th century was, in part, a "protest" against the Catholic church using tradition to interpret Scripture. They wanted to set Scripture over and above the authority of the church. Now you just said that we should interpret Scripture according to the tradition of the church . . .
3 comments:
- Ryan Woods said...
But isn't it somewhat ignorant to believe that we can interpret much without tradition? I don't think anyone in your previous post was arguing that we should place tradition higher than scriptural authority but without tradition we don't have the trinity, we don't have the cannon, we don't have the roots to the tree of salvation (to borrow a metaphor from Paul in Romans 11).
Granted I'm not much of a scholar (especially compared to some of the other people who commented on your blog) but I've always thought that was a problem in the churches of Christ base. We had an assumption that we could enter into the text without any of our baggage (with no filter or paradigm whatsoever) and we fast forwarded from the New Testament church to Stone and Campbell as if there was nothing of value in between. I always thought there was a lot of ignorance in that...then again I'm completely ignorant myself...oh well.
- rich jandt said...
Ryan has a very good point, Our traditions and our cultural situations are the basis in which we read the Bible.
I say that we are not able to interpret without our traditions. When I would write long boring papers about varieous topics or teachings I would spend a lot of time reading history or ancient cultural influences.
Remember the first century Church put tradition before scripture, because they didn't have the scriptures. All they had to work on were the prophecies of others and preaching of those who had been with Jesus.
- Tim said...
I think we're seeing right now, as with Stone & Campbell, who disagreed with each other on many things, a time of great disagreement and reevaluation of our traditions on what is important and what is not, especially as they pertain to how we interpret the Gospel, and also what our actions are based on that interpretation. We've got a huge responsibility to stay true to Scripture while either keeping our traditions, or by throwing out the ones that hinder us from following God's commands.
I think we're in a time right now that is ready to swing the other way on the pendulum away from traditions. I fear we'll swing too far and forget the things that remind us of who we are and who we belong to.


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Your Three Best Plays on Today's "Range-Bound" Oil
We are in the early stages of what may be the most significant revision in energy investments to occur in a decade (or more), and for me, that has meant yet another day full of meetings. As we just adjourned for lunch, I took the opportunity to fill you in on what's been going on here.
The situation remains fluid, although the financing involved is quite large and likely to come in stages.
As this unfolds, I will advise you of what is about to happen, and how to play it. You will also be receiving a "heads up" as soon as the strategy has been settled.
Now, that may not happen until next week. For now, suffice to say that huge worldwide sources of funding are about to start investing globally – and especially in the U.S. – in what will be much more than just another merger and acquisition cycle.
But until I have concrete indicators to pass along, let's today consider a more immediate concern: how to best play oil prices that keep bouncing up and down within a "range," as they have this week.
It's actually quite simple…
Oil is Up 4% One Day, and Down 4% the Next
Here's what I mean. Crude oil prices in New York dropped 4.4% yesterday after a 4.6% rise on Tuesday. This morning the price was rising again by some 2%.
Welcome to our latest period of "range-bound" oil.
On June 23 WTI (West Texas Intermediate, the oil grade used in setting futures contract prices on the NYMEX) eked past $50 a barrel. Yet since then the price has declined 10.7% through close yesterday.
Now some observers had initially suggested there would be a rather straight line from $50 to the low $60s. After all, just about everybody (including myself) believe that is the level the market will realize in the fourth quarter of this year or the first of 2017.
However, I had suggested that we would approach $50 and then find some significant resistance there. My take was not that we would be then collapsing back to the $30s.
Rather, this rise in price is going to be gradual and, as I have put it a number of times before, "ratcheted" going forward (i.e., the overall move up will be accentuated by occasional reversals).
In short, the crude oil situation is stabilizing but in a very different environment than we have experienced in the past. With the massive extractable oil largess unfolding in several places, principally because of massive unconventional (shale and tight) oil in the U.S., the supply side of the supply-demand balance is driving restraint.
Of course, the volume must actually be extracted at the wellhead before it has a genuine impact on market price, as I explained on Tuesday. Nonetheless, traders who actually determine the daily prices via WTI and Dated Brent (the London equivalent) as the yardsticks for setting futures contracts tend to react ahead of the curve.
Here's why…
Traders Tend to Accelerate Oil Price Movements
On any given trading day, there are many more futures contracts ("paper" barrels) than actual consignments of oil ("wet" barrels) circulating in the market. A trader makes money by arbitraging between these two.
As we have discussed before, traders need to estimate ranges of implied volatility upon which to determine options as "insurance policies" on the futures contracts. Futures require that one buy a commodity at a stated price and time. Options provide the right but not the obligation to do so.
Traders are almost never interested in owning the actual commodity – instead, their focus is on making a profit off of it. The options provide the leverage to sell the futures contract prior to expiration (by effectively cancelling out the contract).
Traders try to gauge prices by estimating where the market will go. In stable times, they will peg their contracts on the expected cost of the next available barrel of oil. When oil prices are going up, that will translate into the expected most expensive barrel; when they are declining, it will translate into the least expensive.
That means traders will push the market in the direction it's already heading more aggressively than the actual underlying dynamics justify.
When that happens, your best bet is simply to "jump on the bandwagon" and do whatever the traders are doing.
Unfortunately, that won't work when oil prices are "range-bound" – bouncing between two prices – as they are now, as things will move to fast for regular investors.
And even if you stayed glued to your computer screen, you're most likely not involved in the futures contract trade (nor should you be), which is what the traders use.
But as luck would have it, there's a simple way to trade "range-bound" oil…
How You Can Best Play "Range-Bound" Oil
The tool I recommend you use are select exchange traded funds (ETFs) or parallel exchange traded notes (ETNs). These allow you to play an entire market segment without having to invest in the underlying commodities themselves, or in a multitude of individual companies.
In fact, ETFs and ETNs should be a part of your portfolio in any event. But they are even more important in the "bounded" trading environment we have in oil today.
When it comes to oil, there are two kinds of ETFs and ETNs to consider.
First are ones dealing with oil itself, as well as the direction of oil's price. There are also "bear" and "bull" funds, that magnify the movement of the oil price up to three times (in reverse, for "bear" funds).
As you'd expect, such funds are also subject to high volatility.
Second are a number of funds that provide exposure to a wide group of companies – according to function (for example, producers, oil field services, distributors, midstream pipelines and storage, equipment, refining), global range (broad global to region-specific), and size (small caps, blue-chip).
A rule of thumb when using ETFs and ETNs in the present range-bound environment is this: it makes sense to stay away from funds that focus on small companies, given the acute debt crisis among operators underway in the U.S. market.
Broad exposure is preferable, with funds that have sufficient trading liquidity and low management fees.
Among the many currently available funds, the best straight exposure to oil is United States Oil Fund LP (USO), while a good exposure to the broadest range of producers is provided by SPDR S&P Oil & Gas Exploration & Production ETF (XOP).
If instead you're most interested in oil field services – the market segment that is likely to experience improvement first, before oil producers themselves – the fund to look at would be VanEck Vectors Oil Services ETF (OIH).
Now, with oil prices stuck in their current range, timing will be everything.
P.S. Stay tuned for next week, when I'll have more from my finance meetings. It's going to be big…


text: Book Reviews, Four Stars, Posts September 7, 2016 Dream Houses by Genevieve Valentine Hey guys, it's the start of September, and you know what that means? IT'S ONLY *unintelligable mumbling* MORE DAYS 'TIL HALLOWEEN, YEAHHHHH! 'TIS THE SEASON of pumpkins, cheap plastic skeletons, chewy chocolate candy, and an… Read Post


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AzianiIron.com owner and director Rachel Aziani has announced the release of its first title from Aziani Iron. Rachel Aziani Presents: Aziani's Iron Girls is now available at retailers worldwide. The DVD is being exclusively distributed by VIP Digital Media.
Aziani's Iron Girls introduces some of the world's sexiest female bodybuilder (FBB) and fitness models, who love to get naked and naughty. The first release features Megan Avalon aka "The Muscle Barbie," as well as Ashlee Chambers, Brandi Mae, and never-before-seen amateurs Abby Marie, Briana Beau, Amber DeLuca, and Angela Salvagno.
According to Rachel, "We created this movie to feature female bodybuilders and fitness models in a way seldom seen before. The consumers are able to see their favorite models in a sexy, positive and elegant way. I have really strived to share the personality of each model by truly interacting with them throughout the entire shooting session.
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VIP Digital Media Sales Manager David Peskin said, "Right when we blasted the box cover for this release, it was apparent this has been a major void in the marketplace. The title just streeted, and we are already getting strong re-orders. Rachel also added two explosive bonus boy/girl scenes to the DVD. Aziani's Iron Girls is an absolute winner!"
Both Companies announced at press time the next DVD, Aziani's Iron Girls 2 is scheduled to release at the end of April. Peskin suggested that retail buyers and distributors pre-order the title now.
Retailers can view Aziani's Iron Girls' DVD artwork and trailer by clicking here.
For domestic and foreign sales for DVD, VOD, broadcast and licensing, call or email David Peskin at 818-709-8200 or [email protected]


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Hoedspruit – A South African Gem
In the South African Gem series of my blog, I will discuss an area of our beautiful country that I've visited before. Our country has so much to offer and many people do not even know of half the places you could go to, or things you could do. I truly believe in South Africa we are greatly blessed with one of a kind scenery and abundant wildlife and untouched raw beauty.
First on my radar is the majestic farming town at the foot of the Klein Drakensberg in the Limpopo province, Hoedspruit. So, obviously the scenery is unbelievably beautiful, and can be admired by the many viewing points along the winding road, AKA the Panorama route. The town focuses a lot on eco-tourism, and has numerous wildlife sanctuaries, breeding, and rehabilitation centres, which totally scores them a ton of brownie points.
In the immediate vicinity of Hoedspruit there is a long list of places to see, and things to do. Amongst these is the Blyde River Canyon, which can be viewed from any of the stops on the Panorama route, they include, the Three Rondawels God's window, Bourke's Luck Potholes, and the Pinnacle.
There is also the Hoedspruit Endangered Species Centre, which was originally started to care for cheetahs, which is being threatened in their natural habitats not only by bigger cats like lions and leopards, but also by humans; Mostly farmers trying to protect their own live stock, which is helpless against wild predators like the cheetah, lion, and leopard.
The centre focuses mainly on the conservation of rare, vulnerable or endangered animals. Cheetah Conservation is one of their core disciplines. The centre has grown since First opening their doors in early 90's and is now looking after a number of other endangered wildlife species, like Vultures, wild dogs, Ground Hornbill, and Rhino, to name a few.
Here you can see the Vultures landing at the "Vulture Restaurant". Some of these Vultures fly from as far as Pilansberg. The main threat to vultures are poison, the alarming thing is that in most of the cases the poison was used for other animals, indirectly also poisoning the vultures when they feast on these carcasses.
The five common vulture species found in the Limpopo area are:
~ White-backed vulture
~ Cape vulture
~ Lappet-faced vulture
~ White-headed vulture
~ Hooded vulture
Out of the eleven vulture species found in Africa, ten of them are on the threatened or near-threatened list, of which four are classified as critically endangered. They are; the Hooded Vulture, the White-backed Vulture, the White-headed Vulture, and the Rüppell's Vulture. You can see that two of these are found in the Limpopo area.
The centre also has a pair of Southern Ground Hornbill. They are currently considered 'vulnerable' by the IUCN, but sadly they are classified as 'Endangered' in South Africa. In many ways these massive carnivores are making it very difficult for conservationists to protect, and maybe even try to increase their numbers. The problem is three-fold; Hornbills mate for life, and in many cases even after one of the partners have died off the other will not accept another partner for the rest of their lives, on the other hand, the female gives birth to two eggs, one hatching a few days before the other, the mother, or feeder will only bring enough food for one of them, in the end the older and naturally bigger bird will always win the fight for food, leaving his or her sibling to starve to death. And lastly, the fledgling period can sometimes take up to two years, and if the timing is wrong (ie, at the end of mating season) the period from one hatchling to the next can sometimes be as much as three years.
The centre also looks after two ex-circus lions rescued from an abandoned zoo in South America. The male was neutered at an unnaturally young age, confusing his growth hormones, leaving him without a main and almost twice the size of a normal male lion. They also pulled both of the lion's claws. When the circus went bankrupt the owners literally just left all the animals for dead. People who came to know of this, contacted the centre and not only helped them get the lions here, but also built the enclosure they are kept at the centre.
The Hoedspruit Endangered Species Centre is a non-profit organisation and generates most of its income from donations and sponsorships. It is one of the leading conservation centres, and is also contributing valuable research to the field of conservation and breeding of endangered species. You can visit their website: http://www.hesc.co.za, or phone for an appointment on 015 793 1633. There are many more heart-warming and inspiring stories at the centre.
Other activities in the Hoedspruit area that you might enjoy;
Moholoholo Wildlife Rehabilitation Centre; moholoholo.co.za; 015 795 5236
Blyde dam Boat Cruise; 072 260 4212
Khamai Reptile Park
Baloon Safaris Hoedspruit; goddingandgodding.com; 072 467 3310
African Summer Spa; africasummerspa.co.za; 015 793 1895
Elephant Back Safaris
Eco Caves
Mac Mac falls
Birdlife international. 2016. African vulture pilot study aims to reduce poisoning deaths. http://www.birdlife.org/africa/news/african-vulture-pilot-study-aims-reduce-poisoning-deaths. Accessed 01April 2016.


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text:
Were the U.S. to persistently earn substantially more on its foreign investments ("U.S. claims") than foreigners earn on their U.S. investments ("U.S. liabilities"), the likelihood that the current environment of sizeable global imbalances will evolve in a benign manner increases. However, utilizing data on the actual foreign equity and bond portfolios of U.S. investors and the U.S. equity and bond portfolios of foreign investors, we find that the returns differential of U.S. claims over U.S. liabilities is essentially zero. Ending our sample in 2005, the differential is positive, whereas through 2004 it is negative; in both cases the differential is statistically indecipherable from zero. Moreover, were it not for the poor timing of investors from developed countries, who tend to shift their U.S. portfolios toward (or away from) equities prior to the subsequent underperformance (or strong performance) of equities, the returns differential would be even lower. Thus, in the context of equity and bond portfolios we find no evidence that the U.S. can count on earning more on its claims than it pays on its liabilities.
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text:
Video: Azealia Banks - "Chasing Time"
From her great surprise-released record Broke with Expensive Taste.
Azealia Banks surprised just about everyone when she surprise-released her long-awaited debut LP Broke With Expensive Taste last week, and to celebrate she's just shared the video for her single "Chasing Time." It's a great clip featuring plenty of great outfits, dance moves, and CGI effects, as well as Azealia's now-trademark closeup shots of her rapping very fast. What's not to love! Check it out.


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SUMMARY: Active female members of the US military make up 15% of all active-duty service members, and the unintended pregnancy rate is 50% higher than their civilian counterparts. Dr Daniel Grossman, vice-president of research at Ibis Reproductive Health outlines that an unplanned pregnancy can be an obstacle to the career of a military woman. The US military has one of the most comprehensive health-care systems, Tricare, which covers most FDA approved contraceptives. However, the issue is more that contraceptive measures are simply not available to women while on active-duty. Both houses of congress are working on a bill that attempts to resolve the issue of contraception in the US military, which includes family planning education and counseling, and a provision of specific contraceptive for the entire duration of their deployment.
SOURCE: Michelle Andrews, August 11 2015, 'Women in Combat Zones can have Trouble Getting Contraceptives,' NPR, http://www.npr.org/sections/health-shots/2015/08/11/431382325/women-in-combat-zones-can-have-trouble-getting-contraceptives


text:
By: Joanna
YAWN!June 28, 2018
Hey errybody! Nice to see you all here. We are quite fed up of this censorship malarky. We're finding that we're…Read More
Christmas Life Drawing With Live Christmas Songs!December 5, 2017
Hey ho yo ho! Our normal weekly sketching club at Sloans will be held at the excellent SWG3 down on Eastvale…Read More
Free sketching at Cass ArtDecember 4, 2017
Cass Art Life Drawing Hey yo! Nothing like a little bit of afternoon life drawing to get you inspired… Thank you…Read More
We'll sing from the rooftops if we have to!November 21, 2017
Hiya friends, I'm having a tough time here at ATYN HQ. Established in 2009 at The Flying Duck in Glasgow, ATYN…Read More
The sound you want to hearAugust 9, 2017
Thank you all for a successful 2nd week of Life Drawing in Edinburgh at The Fringe! Thank you to Rosie from Whitespace for…Read More
Life Drawing at The Edinburgh Festival – 1/4July 27, 2017
Hello my dears. Every year it creeps up on us, and every year, we are as unprepared as ever…! Our dear…Read More
Alphonse Mucha and All The Young Nudes aligned…February 9, 2017
Exciting opportunities and ideas are constantly presenting themselves to us here at All The Young Nudes. This February, we were asked…Read More
Up for air…February 3, 2017
Hello. Hey! How are you all doing? We haven't written for a while. We've been snowed under dear sketchers! It's all…Read More
An open letter to FacebookJune 30, 2016
Rules, rules and yet more rules. Facebook, could you give me a call? Hey again Facebook. We've met before. I know…Read More
Craft ScotlandJune 13, 2016
ATYN's founder Joanna is most excited to be speaking at Craft Scotland in Dundee this October! The event sounds fabulous, and…Read More


text:
Here's a lot of links to the coverage of the change in the editor's chair at America magazine.
First, the magazine's statement. Very pointed, focused mostly on the new editor, Fr. Drew Christiansen, S.J.
He is author of more than 100 articles on moral theology, ethics and international affairs, just war and nonviolence, Catholic social teaching, and family care of the elderly. His most recent book is Forgiveness in International Politics: An Alternative Road to Peace (USCCB, 2004), co-authored with William Bole and Robert T. Hennemeyer.
NYTimes article, which leads with the "Vatican said to push Jesuit off magazine" with quotes expressing surprise and friendship from the likes of Phil Lawler and Fr. Neuhaus:
Catholic experts said yesterday that they were stunned to learn of Father Reese's dismissal. "I'd think of him as sort of a mainstream liberal," said Philip F. Lawler, the editor of Catholic World News, a news outlet on the more conservative end of the spectrum. "I think he's been reasonably politic. I watched him during the transition, and I cannot think of a single thing I heard that would have put him in jeopardy."
The Rev. Richard John Neuhaus, editor of another Catholic journal based in New York, First Things, which is more conservative than America, said yesterday, "It would be fair to say that during the pontificate of John Paul II that America apparently saw itself or at least certainly read as a magazine of what some would describe as the loyal opposition. And, needless to say, there's dispute over the definition of 'loyal' and the definition of 'opposition.' "
But Father Neuhaus added that he considered Father Reese a friend who was always "fair-minded" even when they disagreed.
Then, we get to NCR, which ran first, and which includes details of process which neither of the secular papers pick up:
According to one source, the communication about Reese's fate was carried on between the Congregation for the Doctrine of the Faith and the superior general of the Jesuits, Dutch Fr. Peter-Hans Kolvenbach, with the content then relayed to Reese's Jesuit superiors in the United States. Although critics of Reese both in the United States and Rome have occasionally accused him of an anti-hierarchical mentality, supporters noted in their responses to the congregation that over his seven years as editor, America routinely published weighty pieces by prominent members of the hierarchy, at one stage including Ratzinger himself.
In February 2002, the Congregation for the Doctrine of the Faith proposed creating a three-member commission of censors for the magazine, though the idea was never implemented. According to sources, the congregation told the Jesuits that the action was in response to concern from bishops in the United States.
Sources said no bishops were identified by name and that Reese was never directly contacted. According to a source close to the magazine, Jesuit superiors said some bishops were upset that Reese often commented on church matters for general media and that such commentary should be solely the province of bishops.
Note the actors in the drama not mentioned, as I said, in the other pieces: "some bishops."
One more: the AP story, that mentions, which the others don't, that:
An official at the Jesuit headquarters in Washington, the Rev. Albert Diulio, said Reese and his provincial supervisor had reached the decision together, and noted that Jesuits tend to rotate jobs every six or seven years.
In short, what conflict there was seems to have derived from America's publication of some articles (the NCR piece lists them) which, even though some were published in tandem with articles articulating the Church's teaching, were perceived as defining the magazine's identity - that is the "dissenting" articles, especially those on Dominus Iesus.
I'm intrigued by the hint that American bishops were involved, and amused by the suggestion, tinged with huffiness that The Jesuit was doing what The Bishops should be doing On TV. That's odd, if true. There are about a million Catholic commentators on television, and personally, I think the bishops should be far more concerned with Fr. McBrien becoming the default Catholic Clerical Expert on Pundit TV. Secondly, I'm not sensing that many bishops are jumping to do what Reese has done on television. I would suspect most of them are perfectly content to let an expert on the process of papal elections do the commentary on the same. If there's a bishop who wants to get on television, let his people call their people - I can't see a booker saying no to that, myself.
And do remember, on the other hand, the special relationship the Jesuits have, in theory to the Pope. That's why America would come under scrutiny while other journals might not.
More will undoubtedly be said and come out on this over the next few days. And I certainly hope there is, particularly from this side of the sea. Will someone from the Jesuits come out and say, on the record, what happened? After all, I'm sure this is going to be the occasion of some concerns being expressed about openness, about the importance of honesty in dialogue within the Church. Well, let's get started then: let's hear what really happened, for the record, on the record. Because the general impact of relying on rumors and anonymous sources is that we're left with the clear implication that this is, as one of my correspondents said, a "first scalp." If it is, that would be useful to know. If it's not - if it's merely the confluence of events - the normal tenure of a Jesuit in one position is up, combined with some tensions and a sense that now's the time for change - that would be useful and clarifying to know, as well. We've tried to demystify the selection of the Pope and other members of the hierarchy.Good! Now let's demystify the de-selection of the editor of America.


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William Edward Ayrton
- Birthdate
- 1847
- Death date
- 1908
- Fields of study
- Telegraphy
William Edward Ayrton was a British electrical engineer and physicist known for his contributions to electrical measuring instruments and for the development of technological infrastructure in India and Japan.
Ayrton was born in 1847 to a well-connected London family. His father, a noted barrister and linguist, pushed him to excel in school, where he won scholarships in mathematics. These scholarly achievements led to a year-long fellowship to study electrical theory and laboratory technique with Sir William Thomson (later Lord Kelvin) at the University of Glasgow in 1867. Following a subsequent year of study in Europe, he went to India, where he helped develop a system for identifying faults in overland telegraph lines being strung across this British colony.
In 1873, he and his first wife, Matilda, moved to Japan, where the modernizing Meiji government hired him to teach physics and telegraphy at Tokyo's Imperial College of Engineering. He developed a contested relationship with the Meiji leadership, promoting independent research by his Japanese students while also insisting that foreign supervision was necessary to operate its national telegraph system. Although his five-year contract was not renewed, Ayrton remained celebrated for opening Japan's first public electric lighting system at Tokyo's central telegraph station in 1878.
He returned to London in 1879 and took a professorship of physics at Finsbury, applying a model of technical education that proved very popular. Along with teaching, he worked with long-time collaborator John Perry on practical applications of electromagnetism. They developed a number of devices—the ammeter and the wattmeter—that allowed for the direct-reading of electrical output and resistance, along with a clock-based domestic electricity meter. They also pioneered electric transportation systems, such as the first electric tricycle and the block contact switching system, which prevented two electric trains from sharing the same stretch of track.
His second wife was Hertha Marks Ayrton. They married in 1885 and collaborated on many research projects. Hertha Ayrton became the first female member of the Institution of Electrical Engineers.
Ayrton continued to teach, with the requirement that his work could not include commercial consulting. He also served on various English scientific societies and was often hired as an expert witness in patent disputes. He died in 1908.
Further Reading
Yuzo Takahashi, "William Edward Ayrton at the Imperial College of Engineering in Tokyo--The First Professor of Electrical Engineering in the World," IEEE Transactions on Education, Vol. 33, No. 2 (May 1990).


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For other uses, see Asphalt (disambiguation). Note: The terms bitumen and asphalt are mostly interchangeable, Asphalt Pavement Construction in Westcliff except where asphalt is used as a shorthand for asphalt concrete. Natural bitumen from the Dead Sea Refined asphalt The University of Queensland pitch drop experiment, demonstrating the viscosity of asphalt
Asphalt (/ˈæsˌfɔːlt, -ˌfɑːlt/), also known as bitumen (UK English: /ˈbɪtʃəmən, ˈbɪtjʊmən/,[1] US English: /bɪˈt(j)uːmən, baɪˈt(j)uːmən/)[2] is a sticky, black, and highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term asphaltum was also used.
The primary use (70%) of asphalt Driveway Block Paving Cost is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other main uses are for bituminous waterproofing products, including production of roofing felt and for sealing flat roofs.
The terms "asphalt" and "bitumen" are often used interchangeably to mean both natural and manufactured forms of the substance. In American English, "asphalt" (or "asphalt cement") is commonly used for a refined residue from the distillation process of selected crude oils. Outside the United States, the product is often called "bitumen", and geologists worldwide often prefer the term for the naturally occurring variety. Common colloquial usage often refers to various forms of asphalt as "tar", as in the name of the La Brea Tar Pits.
Naturally occurring asphalt is sometimes specified by the term "crude bitumen". Asphalt Pavement Construction Its viscosity is similar to that of cold molasses[6][7] while the material obtained from the fractional distillation of crude oil boiling at 525 °C (977 °F) is sometimes referred to as "refined bitumen". The Canadian province of Alberta has most of the world's reserves of natural asphalt in the Athabasca oil sands, which cover 142,000 square kilometres (55,000 sq mi), an area larger than England.
The word "asphalt" is derived from the late Middle English, in turn from French asphalte, based on Late Latin asphalton, asphaltum, which is the latinisation of the Greek ἄσφαλτος (ásphaltos, ásphalton), a word meaning "asphalt/bitumen/pitch" which perhaps derives from ἀ-, "without" and σφάλλω (sfallō), "make fall". Asphalt Companies Hiring Near Me the first use of asphalt by the ancients was in the nature of a cement for securing or joining together various objects, and it thus seems likely that the name itself was expressive of this application. Specifically, Herodotus mentioned that bitumen was brought to Babylon to build its gigantic fortification wall.[11] From the Greek, the word passed into late Latin, and thence into French (asphalte) and English ("asphaltum" and "asphalt"). In French, the term asphalte is used for naturally occurring asphalt-soaked limestone deposits, and for specialised manufactured products with fewer voids or greater bitumen content than the "asphaltic concrete" used to pave roads.
The expression "bitumen" originated in the Sanskrit words jatu, meaning "pitch", and jatu-krit, meaning "pitch creating" or "pitch producing" (referring to coniferous or resinous trees). The Latin equivalent is claimed by some to be originally gwitu-men (pertaining to pitch), and by others, pixtumens (exuding or bubbling pitch), which was subsequently shortened to bitumen, thence passing via French into English. From the same root is derived the Anglo-Saxon word cwidu (mastix), the German word Kitt (cement or mastic) and the old Norse word kvada.
In British English, "bitumen" is used instead of "asphalt". The word "asphalt" is instead used to refer to asphalt concrete, a mixture of construction aggregate and asphalt itself (also called "tarmac" in common parlance). Bitumen mixed with clay was usually called "asphaltum",[13] but the term is less commonly used today.[citation needed]
In Australian English, "bitumen" is often used as the generic term for road surfaces.
In American English, "asphalt" is equivalent to the British "bitumen". However, "asphalt" is also commonly used as a shortened form of "asphalt concrete" (therefore equivalent to the British "asphalt" or "tarmac").
In Canadian English, the word "bitumen" is used to refer to the vast Canadian deposits of extremely heavy crude oil,[14] while "asphalt" is used for the oil refinery product. Diluted bitumen (diluted with naphtha to make it flow in pipelines) is known as "dilbit" in the Canadian petroleum industry, while bitumen "upgraded" to synthetic crude oil is known as "syncrude", and syncrude blended with bitumen is called "synbit".[15]
"Bitumen" is still the preferred geological term for naturally occurring deposits of the solid or semi-solid form of petroleum. "Bituminous rock" is a form of sandstone impregnated with bitumen. The tar sands of Alberta, Canada are a similar material.
Neither of the terms "asphalt" or "bitumen" should be confused with tar or coal tars.[further explanation needed]
See also: Asphaltene
The components of asphalt include four main classes of compounds:
The naphthene aromatics and polar aromatics are typically the majority components. Most natural bitumens also contain organosulfur compounds, resulting in an overall sulfur content of up to 4%. Nickel and vanadium are found at <10 parts per million, as is typical of some petroleum.
The substance is soluble in carbon disulfide. It is commonly modelled as a colloid, with asphaltenes as the dispersed phase and maltenes as the continuous phase.[16] "It is almost impossible to separate and identify all the different molecules of asphalt, because the number of molecules with different chemical structure is extremely large".
Asphalt may be confused with coal tar, which is a visually similar black, thermoplastic material produced by the destructive distillation of coal. During the early and mid-20th century, when town gas was produced, coal tar was a readily available byproduct and extensively used as the binder for road aggregates. The addition of coal tar to macadam roads led to the word "tarmac", which is now used in common parlance to refer to road-making materials. However, since the 1970s, when natural gas succeeded town gas, asphalt has completely overtaken the use of coal tar in these applications. Other examples of this confusion include the La Brea Tar Pits and the Canadian oil sands, both of which actually contain natural bitumen rather than tar. "Pitch" is another term sometimes informally used at times to refer to asphalt, as in Pitch Lake.
Bituminous outcrop of the Puy de la Poix, Clermont-Ferrand, France
The majority of asphalt used commercially is obtained from petroleum.[18] Nonetheless, large amounts of asphalt occur in concentrated form in nature. Naturally occurring deposits of bitumen are formed from the remains of ancient, microscopic algae (diatoms) and other once-living things. These remains were deposited in the mud on the bottom of the ocean or lake where the organisms lived. Under the heat (above 50 °C) and pressure of burial deep in the earth, the remains were transformed into materials such as bitumen, kerogen, or petroleum.
Natural deposits of bitumen include lakes such as the Pitch Lake in Trinidad and Tobago and Lake Bermudez in Venezuela. Natural seeps occur in the La Brea Tar Pits and in the Dead Sea.
Bitumen also occurs in unconsolidated sandstones known as "oil sands" in Alberta, Canada, and the similar "tar sands" in Utah, US. The Canadian province of Alberta has most of the world's reserves, in three huge deposits covering 142,000 square kilometres (55,000 sq mi), an area larger than England or New York state. These bituminous sands contain 166 billion barrels (26.4×10^9 m3) of commercially established oil reserves, giving Canada the third largest oil reserves in the world. Although historically it was used without refining to pave roads, nearly all of the output is now used as raw material for oil refineries in Canada and the United States.
The world's largest deposit of natural bitumen, known as the Athabasca oil sands, is located in the McMurray Formation of Northern Alberta. This formation is from the early Cretaceous, and is composed of numerous lenses of oil-bearing sand with up to 20% oil.[19] Isotopic studies show the oil deposits to be about 110 million years old.[20] Two smaller but still very large formations occur in the Peace River oil sands and the Cold Lake oil sands, to the west and southeast of the Athabasca oil sands, respectively. Of the Alberta deposits, only parts of the Athabasca oil sands are shallow enough to be suitable for surface mining. The other 80% has to be produced by oil wells using enhanced oil recovery techniques like steam-assisted gravity drainage.
Much smaller heavy oil or bitumen deposits also occur in the Uinta Basin in Utah, US. The Tar Sand Triangle deposit, for example, is roughly 6% bitumen.
Bitumen may occur in hydrothermal veins. An example of this is within the Uinta Basin of Utah, in the US, where there is a swarm of laterally and vertically extensive veins composed of a solid hydrocarbon termed Gilsonite. These veins formed by the polymerization and solidification of hydrocarbons that were mobilized from the deeper oil shales of the Green River Formation during burial and diagenesis.
Bitumen is similar to the organic matter in carbonaceous meteorites.[23] However, detailed studies have shown these materials to be distinct.[24] The vast Alberta bitumen resources are considered to have started out as living material from marine plants and animals, mainly algae, that died millions of years ago when an ancient ocean covered Alberta. They were covered by mud, buried deeply over time, and gently cooked into oil by geothermal heat at a temperature of 50 to 150 °C (120 to 300 °F). Due to pressure from the rising of the Rocky Mountains in southwestern Alberta, 80 to 55 million years ago, the oil was driven northeast hundreds of kilometres and trapped into underground sand deposits left behind by ancient river beds and ocean beaches, thus forming the oil sands.
The use of natural bitumen for waterproofing, and as an adhesive dates at least to the fifth millennium BC, with a crop storage basket discovered in Mehrgarh, of the Indus Valley Civilization, lined with it.[25] By the 3rd millennia BC refined rock asphalt was in use, in the region, and was used to waterproof the Great Bath, Mohenjo-daro.
In the ancient Middle East, the Sumerians used natural bitumen deposits for mortar between bricks and stones, to cement parts of carvings, such as eyes, into place, for ship caulking, and for waterproofing.[3] The Greek historian Herodotus said hot bitumen was used as mortar in the walls of Babylon.
The 1 kilometre (0.62 mi) long Euphrates Tunnel beneath the river Euphrates at Babylon in the time of Queen Semiramis (ca. 800 BC) was reportedly constructed of burnt bricks covered with bitumen as a waterproofing agent.
Bitumen was used by ancient Egyptians to embalm mummies.[3][28] The Persian word for asphalt is moom, which is related to the English word mummy. The Egyptians' primary source of bitumen was the Dead Sea, which the Romans knew as Palus Asphaltites (Asphalt Lake).
Approximately 40 AD, Dioscorides described the Dead Sea material as Judaicum bitumen, and noted other places in the region where it could be found.[29] The Sidon bitumen is thought to refer to material found at Hasbeya.[30] Pliny refers also to bitumen being found in Epirus. It was a valuable strategic resource, the object of the first known battle for a hydrocarbon deposit—between the Seleucids and the Nabateans in 312 BC.
In the ancient Far East, natural bitumen was slowly boiled to get rid of the higher fractions, leaving a thermoplastic material of higher molecular weight that when layered on objects became quite hard upon cooling. This was used to cover objects that needed waterproofing,[3] such as scabbards and other items. Statuettes of household deities were also cast with this type of material in Japan, and probably also in China.
In North America, archaeological recovery has indicated bitumen was sometimes used to adhere stone projectile points to wooden shafts.[32] In Canada, aboriginal people used bitumen seeping out of the banks of the Athabasca and other rivers to waterproof birch bark canoes, and also heated it in smudge pots to ward off mosquitoes in the summer.
In 1553, Pierre Belon described in his work Observations that pissasphalto, a mixture of pitch and bitumen, was used in the Republic of Ragusa (now Dubrovnik, Croatia) for tarring of ships.
Bleeding (roads)
An 1838 edition of Mechanics Magazine cites an early use of asphalt in France. A pamphlet dated 1621, by "a certain Monsieur d'Eyrinys, states that he had discovered the existence (of asphaltum) in large quantities in the vicinity of Neufchatel", and that he proposed to use it in a variety of ways – "principally in the construction of air-proof granaries, and in protecting, by means of the arches, the water-courses in the city of Paris from the intrusion of dirt and filth", which at that time made the water unusable. "He expatiates also on the excellence of this material for forming level and durable terraces" in palaces, "the notion of forming such terraces in the streets not one likely to cross the brain of a Parisian of that generation".
But the substance was generally neglected in France until the revolution of 1830. In the 1830s there was a surge of interest, and asphalt became widely used "for pavements, flat roofs, and the lining of cisterns, and in England, some use of it had been made of it for similar purposes". Its rise in Europe was "a sudden phenomenon", after natural deposits were found "in France at Osbann (Bas-Rhin), the Parc (Ain) and the Puy-de-la-Poix (Puy-de-Dôme)", although it could also be made artificially.[35] One of the earliest uses in France was the laying of about 24,000 square yards of Seyssel asphalt at the Place de la Concorde in 1835.
Among the earlier uses of bitumen in the United Kingdom was for etching. William Salmon's Polygraphice (1673) provides a recipe for varnish used in etching, consisting of three ounces of virgin wax, two ounces of mastic, and one ounce of asphaltum.[37] By the fifth edition in 1685, he had included more asphaltum recipes from other sources.
The first British patent for the use of asphalt was "Cassell's patent asphalte or bitumen" in 1834.[35] Then on 25 November 1837, Richard Tappin Claridge patented the use of Seyssel asphalt (patent #7849), for use in asphalte pavement,[39][40] having seen it employed in France and Belgium when visiting with Frederick Walter Simms, who worked with him on the introduction of asphalt to Britain.[41][42] Dr T. Lamb Phipson writes that his father, Samuel Ryland Phipson, a friend of Claridge, was also "instrumental in introducing the asphalte pavement (in 1836)".[43] Indeed, mastic pavements had been previously employed at Vauxhall by a competitor of Claridge, but without success.
Diverging diamond interchange
Claridge obtained a patent in Scotland on 27 March 1838, and obtained a patent in Ireland on 23 April 1838. In 1851, extensions for the 1837 patent and for both 1838 patents were sought by the trustees of a company previously formed by Claridge. Claridge's Patent Asphalte Company—formed in 1838 for the purpose of introducing to Britain "Asphalte in its natural state from the mine at Pyrimont Seysell in France",—"laid one of the first asphalt pavements in Whitehall". Trials were made of the pavement in 1838 on the footway in Whitehall, the stable at Knightsbridge Barracks,"and subsequently on the space at the bottom of the steps leading from Waterloo Place to St. James Park". "The formation in 1838 of Claridge's Patent Asphalte Company (with a distinguished list of aristocratic patrons, and Marc and Isambard Brunel as, respectively, a trustee and consulting engineer), gave an enormous impetus to the development of a British asphalt industry".[45] "By the end of 1838, at least two other companies, Robinson's and the Bastenne company, were in production",[50] with asphalt being laid as paving at Brighton, Herne Bay, Canterbury, Kensington, the Strand, and a large floor area in Bunhill-row, while meantime Claridge's Whitehall paving "continue(d) in good order".
Asphalt Pavement Construction in Westcliff ?Permeable paving demonstration Stone paving in Santarém, Portugal
Permeable paving is a method of paving vehicle and pedestrian pathways that allows for infiltration of fluids. In pavement design the base is the top portion of the roadway that pedestrians or vehicles come into contact with. The media used for the base of permeable paving may be porous to allow for fluids to flow through it or nonporous media that are spaced so that fluid may flow in between the crack may be used. In addition to reducing surface runoff, permeable paving can trap suspended solids therefore filtering pollutants from stormwater.[1] Examples include roads, paths, and parking lots that are subject to light vehicular traffic, such as cycle-paths, service or emergency access lanes, road and airport shoulders, and residential sidewalks and driveways.
Although some porous paving materials appear nearly indistinguishable from nonporous materials, their environmental effects are qualitatively different. Whether it is pervious concrete, porous asphalt, paving stones or concrete or plastic-based pavers, all these pervious materials allow stormwater to percolate and infiltrate the surface areas, traditionally impervious to the soil below. The goal is to control stormwater at the source, reduce runoff and improve water quality by filtering pollutants in the substrata layers.
Permeable solutions can be based on: porous asphalt and concrete surfaces, concrete pavers (permeable interlocking concrete paving systems – PICP), or polymer-based grass pavers, grids and geocells. Porous pavements and concrete pavers (actually the voids in-between them) enable stormwater to drain through a stone base layer for on-site infiltration and filtering. Polymer based grass grid or cellular paver systems provide load bearing reinforcement for unpaved surfaces of gravel or turf.
Grass pavers, plastic turf reinforcing grids (PTRG), and geocells (cellular confinement systems) are honeycombed 3D grid-cellular systems, made of thin-walled HDPE plastic or other polymer alloys. These provide grass reinforcement, ground stabilization and gravel retention. The 3D structure reinforces infill and transfers vertical loads from the surface, distributing them over a wider area. Selection of the type of cellular grid depends to an extent on the surface material, traffic and loads. The cellular grids are installed on a prepared base layer of open-graded stone (higher void spacing) or engineered stone (stronger). The surface layer may be compacted gravel or topsoil seeded with grass and fertilizer. In addition to load support, the cellular grid reduces compaction of the soil to maintain permeability, while the roots improve permeability due to their root channels.[2]
In new suburban growth, porous pavements protect watersheds. In existing built-up areas and towns, redevelopment and reconstruction are opportunities to implement stormwater water management practices. Permeable paving is an important component in Low Impact Development (LID), a process for land development in the United States that attempts to minimize impacts on water quality and the similar concept of sustainable drainage systems (SuDS) in the United Kingdom.
The infiltration capacity of the native soil is a key design consideration for determining the depth of base rock for stormwater storage or for whether an underdrain system is needed.
Permeable paving surfaces have been demonstrated as effective in managing runoff from paved surfaces.[3][4] Large volumes of urban runoff causes serious erosion and siltation in surface water bodies. Permeable pavers provide a solid ground surface, strong enough to take heavy loads, like large vehicles, while at the same time they allow water to filter through the surface and reach the underlying soils, mimicking natural ground absorption.[5] They can reduce downstream flooding and stream bank erosion, and maintain base flows in rivers to keep ecosystems self-sustaining. Permeable pavers also combat erosion that occurs when grass is dry or dead, by replacing grassed areas in suburban and residential environments.[6]
Permeable paving surfaces keep the pollutants in place in the soil or other material underlying the roadway, and allow water seepage to groundwater recharge while preventing the stream erosion problems. They capture the heavy metals that fall on them, preventing them from washing downstream and accumulating inadvertently in the environment. In the void spaces, naturally occurring micro-organisms digest car oils, leaving little but carbon dioxide and water. Rainwater infiltration is usually less than that of an impervious pavement with a separate stormwater management facility somewhere downstream.[citation needed].in areas where infiltration is not possible due to unsuitable soil conditions permeable pavements are used in the attenuation mode where water is retained in the pavement and slowly released to surface water systems between storm events.
Permeable pavements may give urban trees the rooting space they need to grow to full size. A "structural-soil" pavement base combines structural aggregate with soil; a porous surface admits vital air and water to the rooting zone. This integrates healthy ecology and thriving cities, with the living tree canopy above, the city's traffic on the ground, and living tree roots below. The benefits of permeables on urban tree growth have not been conclusively demonstrated and many researchers have observed tree growth is not increased if construction practices compact materials before permeable pavements are installed.[7][8]
Permeable pavements are designed to replace Effective Impervious Areas (EIAs), not to manage stormwater from other impervious surfaces on site. Use of this technique must be part of an overall on site management system for stormwater, and is not a replacement for other techniques.
Also, in a large storm event, the water table below the porous pavement can rise to a higher level preventing the precipitation from being absorbed into the ground. The additional water is stored in the open graded crushed drain rock base and remains until the subgrade can absorb the water. For clay-based soils, or other low to 'non'-draining soils, it is important to increase the depth of the crushed drain rock base to allow additional capacity for the water as it waits to be infiltrated.
The best way to prevent this problem is to understand the soil infiltration rate, and design the pavement and base depths to meet the volume of water. Or, allow for adequate rain water run off at the pavement design stage.
Highly contaminated runoff can be generated by some land uses where pollutant concentrations exceed those typically found in stormwater. These "hot spots" include commercial plant nurseries, recycling facilities, fueling stations, industrial storage, marinas, some outdoor loading facilities, public works yards, hazardous materials generators (if containers are exposed to rainfall), vehicle service and maintenance areas, and vehicle and equipment washing and steam cleaning facilities. Since porous pavement is an infiltration practice, it should not be applied at stormwater hot spots due to the potential for groundwater contamination. All contaminated runoff should be prevented from entering municipal storm drain systems by using best management practices (BMPs) for the specific industry or activity.[9]
Reference sources differ on whether low or medium traffic volumes and weights are appropriate for porous pavements. For example, around truck loading docks and areas of high commercial traffic, porous pavement is sometimes cited as being inappropriate. However, given the variability of products available, the growing number of existing installations in North America and targeted research by both manufacturers and user agencies, the range of accepted applications seems to be expanding. Some concrete paver companies have developed products specifically for industrial applications. Working examples exist at fire halls, busy retail complex parking lots, and on public and private roads, including intersections in parts of North America with quite severe winter conditions.
Permeable pavements may not be appropriate when land surrounding or draining into the pavement exceeds a 20 percent slope, where pavement is down slope from buildings or where foundations have piped drainage at their footers. The key is to ensure that drainage from other parts of a site is intercepted and dealt with separately rather than being directed onto permeable surfaces.
Cold climates may present special challenges. Road salt contains chlorides that could migrate through the porous pavement into groundwater. Snow plow blades could catch block edges and damage surfaces. Sand cannot be used for snow and ice control on perveous asphalt or concrete because it will plug the pores and reduce permeability. Infiltrating runoff may freeze below the pavement, causing frost heave, though design modifications can reduce this risk. These potential problems do not mean that porous pavement cannot be used in cold climates. Porous pavement designed to reduce frost heave has been used successfully in Norway. Furthermore, experience suggests that rapid drainage below porous surfaces increases the rate of snow melt above.
Some estimates put the cost of permeable paving at two to three times that of conventional asphalt paving. Using permeable paving, however, can reduce the cost of providing larger or more stormwater BMPs on site, and these savings should be factored into any cost analysis. In addition, the off-site environmental impact costs of not reducing on-site stormwater volumes and pollution have historically been ignored or assigned to other groups (local government parks, public works and environmental restoration budgets, fisheries losses, etc.) The City of Olympia, Washington is studying the use of pervious concrete quite closely and finding that new stormwater regulations are making it a viable alternative to storm water.
Some permeable pavements require frequent maintenance because grit or gravel can block the open pores. This is commonly done by industrial vacuums that suck up all the sediment. If maintenance is not carried out on a regular basis, the porous pavements can begin to function more like impervious surfaces. With more advanced paving systems the levels of maintenance needed can be greatly decreased, elastomerically bound glass pavements requires less maintenance than regular concrete paving as the glass bound pavement has 50% more void space.
Plastic grid systems, if selected and installed correctly, are becoming more and more popular with local government maintenance personnel owing to the reduction in maintenance efforts: reduced gravel migration and weed suppression in public park settings.
Some permeable paving products are prone to damage from misuse, such as drivers who tear up patches of plastic & gravel grid systems by "joy riding" on remote parking lots at night. The damage is not difficult to repair but can look unsightly in the meantime. Grass pavers require supplemental watering in the first year to establish the vegetation, otherwise they may need to be re-seeded. Regional climate also means that most grass applications will go dormant during the dry season. While brown vegetation is only a matter of aesthetics, it can influence public support for this type of permeable paving.
Traditional permeable concrete paving bricks tend to lose their color in relatively short time which can be costly to replace or clean and is mainly due to the problem of efflorescence.
Efflorescence is a hardened crystalline deposit of salts, which migrate from the center of concrete or masonry pavers to the surface to form insoluble calcium carbonates that harden on the surface. Given time, these deposits form much like how a stalactite takes shape in a cave, except in this case on a flat surface. Efflorescence usually appears white, gray or black depending on the region.
Over time efflorescence begins to negatively affect the overall appearance of masonry/concrete and may cause the surfaces to become slippery when exposed to moisture. If left unchecked, this efflorescence will harden whereby the calcium/lime deposits begin to affect the integrity of the cementatious surface by slowly eroding away the cement paste and aggregate. In some cases it will also discolor stained or coated surfaces.
Efflorescence forms more quickly in areas that are exposed to excessive amounts of moisture such as near pool decks, spas, and fountains or where irrigation runoff is present. As a result, these affected regions become very slick when wet thereby causing a significant loss of "friction coefficient". This can be of serious concern especially as a public safety issue to individuals, principals and property owners by exposing them to possible injury and increased general liability claims.
Efflorescence remover chemicals can be used to remove calcium/lime build-up without damaging the integrity of the paving surface.
Installation of porous pavements is no more difficult than that of dense pavements, but has different specifications and procedures which must be strictly adhered to. Nine different families of porous paving materials present distinctive advantages and disadvantages for specific applications. Here are examples:Main article: Pervious concrete
Pervious concrete is widely available, can bear frequent traffic, and is universally accessible. Pervious concrete quality depends on the installer's knowledge and experience.[10]
Plastic grids allow for a 100% porous system using structural grid systems for containing and stabilizing either gravel or turf. These grids come in a variety of shapes and sizes depending on use; from pathways to commercial parking lots. These systems have been used readily in Europe for over a decade, but are gaining popularity in North America due to requirements by government for many projects to meet LEED environmental building standards. Plastic grid system are also popular with homeowners due to their lower cost to install, ease of installation, and versatility. The ideal design for this type of grid system is a closed cell system, which prevents gravel/sand/turf from migrating laterally.[citation needed] It is also known as Grass pavers / Turf Pavers in India [11]
Porous asphalt is produced and placed using the same methods as conventional asphalt concrete; it differs in that fine (small) aggregates are omitted from the asphalt mixture. The remaining large, single-sized aggregate particles leave open voids that give the material its porosity and permeability. To ensure pavement strength, fiber may be added to the mix or a polymer-modified asphalt binder may be used.[12] Generally, porous asphalt pavements are designed with a subsurface reservoir that holds water that passes through the pavement, allowing it to evaporate and/or percolate slowly into the surround soils.[13][14]
Open-graded friction courses (OGFC) are a porous asphalt surface course used on highways to improve driving safety by removing water from the surface. Unlike a full-depth porous asphalt pavement, OGFCs do not drain water to the base of a pavement. Instead, they allow water to infiltrate the top 3/4 to 1.5 inch of the pavement and then drain out to the side of the roadway. This can improve the friction characteristics of the road and reducing road spray.[15]
Single-sized aggregate without any binder, e.g. loose gravel, stone-chippings, is another alternative. Although it can only be safely used in very low-speed, low-traffic settings, e.g. car-parks and drives, its potential cumulative area is great.[citation needed]Grass pavement
Porous turf, if properly constructed, can be used for occasional parking like that at churches and stadia. Plastic turf reinforcing grids can be used to support the increased load.[16]:2 [17] Living turf transpires water, actively counteracting the "heat island" with what appears to be a green open lawn.Main article: interlocking concrete pavers
Permeable interlocking concrete pavements are concrete units with open, permeable spaces between the units.[16]:2 They give an architectural appearance, and can bear both light and heavy traffic, particularly interlocking concrete pavers, excepting high-volume or high-speed roads.[18] Some products are polymer-coated and have an entirely porous face.
Permeable clay brick pavements are fired clay brick units with open, permeable spaces between the units. Clay pavers provide a durable surface that allows stormwater runoff to permeate through the joints.Main article: Resin bound paving
Resin bound paving is a mixture of resin binder and aggregate. Clear resin is used to fully coat each aggregate particle before laying. Enough resin is used to allow each aggregate particle to adhere to one another and to the base yet leave voids for water to permeate through. Resin bound paving provides a strong and durable surface that is suitable for pedestrian and vehicular traffic in applications such as pathways, driveways, car parks and access roads.
Elastomerically bound recycled glass porous pavement consisting of bonding processed post consumer glass with a mixture of resins, pigments, granite and binding agents. Approximately 75 percent of glass in the U.S. is disposed in landfills.[19][20]
Stormwater management practices related to roadways:
SealcoatRaised sidewalks beside a 2000-year-old paved road, Pompeii, Italy
A sidewalk (American English) or pavement (British English), also known as a footpath or footway, is a path along the side of a road. A sidewalk may accommodate moderate changes in grade (height) and is normally separated from the vehicular section by a curb. There may also be a median strip or road verge (a strip of vegetation, grass or bushes or trees or a combination of these) either between the sidewalk and the roadway or between the sidewalk and the boundary.
In some places, the same term may also be used for a paved path, trail or footpath that is not next to a road, for example, a path through a park.
The term "sidewalk" is usually preferred in most of North America, along with many other countries worldwide that are not members of the Commonwealth of Nations. The term "pavement" is more common in the United Kingdom,[1] as well as parts of the Mid-Atlantic United States such as Philadelphia and New Jersey.[2][3] Many Commonwealth countries use the term "footpath". The professional, civil engineering and legal term for this in North America is "sidewalk" while in the United Kingdom it is "footway".[4]
In the United States, the term sidewalk is used for the pedestrian path beside a road. "Shared use paths" or "multi-use paths" are available for use by both pedestrians and bicyclists.[5] "Walkway" is a more comprehensive term that includes stairs, ramps, passageways, and related structures that facilitate the use of a path as well as the sidewalk.[6]
In the UK, the term "footpath" is mostly used for paths that do not abut a roadway.[7] The term "shared-use path" is used where cyclists are also able to use the same section of path as pedestrians.[8]East India House, Leadenhall Street, London, 1766. The sidewalk is separated from the main street by six bollards in front of the building.
There is evidence that sidewalks were built in ancient times. It was claimed that the Greek city of Corinth was paved by the 4th-century, and the Romans were particularly prolific sidewalk builders – they called them semitas.[9]
However, by the Middle Ages, narrow roads had reverted to being simultaneously used by pedestrians and wagons without any formal separation between the two categories. Early attempts at ensuring the adequate maintenance of foot-ways or sidewalks were often made, such as the 1623 Act for Colchester, although they were generally not very effective.[10]
Following the Great Fire of London in 1666, attempts were slowly made to bring some order to the sprawling city. In 1671, 'Certain Orders, Rules and Directions Touching the Paving and Cleansing The Streets, Lanes and Common Passages within the City of London' were formulated, calling for all streets to be adequately paved for pedestrians with cobblestones. Purbeck stone was widely used as a durable paving material. Bollards were also installed to protect pedestrians from the traffic in the middle of the road.
A series of Paving Acts from the House of Commons during the 18th century, especially the 1766 Paving & Lighting Act, authorized the City of London Corporation to create foot-ways throughout all the streets of London, to pave them with Purbeck stone (the thoroughfare in the middle was generally cobblestone) and to raise them above the street level with curbs forming the separation.[11] The Corporation was also made responsible for the regular upkeep of the roads, including their cleaning and repair, for which they charged a tax from 1766.[12] By the late 19th-century large and spacious sidewalks were routinely constructed in European capitals, and were associated with urban sophistication.
In the United States, adjoining property owners must in most situations finance all or part of the cost of sidewalk construction. In a legal case in 1917 involving E. L. Stewart, a former member of the Louisiana House of Representatives and a lawyer in Minden in Webster Parish, the Louisiana Supreme Court ruled that owners must pay whether they wish for the sidewalk to be constructed or not.[13]Pedestrians walking on the pavement (sidewalk) in London.
Sidewalks play an important role in transportation, as they provide a safe path for people to walk along that is separated from the motorized traffic. They aid road safety by minimizing interaction between pedestrians and motorized traffic. Sidewalks are normally in pairs, one on each side of the road, with the center section of the road for motorized vehicles.
In rural roads, sidewalks may not be present as the amount of traffic (pedestrian or motorized) may not be enough to justify separating the two. In suburban and urban areas, sidewalks are more common. In town and city centers (known as downtown in North America) the amount of pedestrian traffic can exceed motorized traffic, and in this case the sidewalks can occupy more than half of the width of the road, or the whole road can be reserved for pedestrians, see Pedestrian zone.
Sidewalks may have a small effect on reducing vehicle miles traveled and carbon dioxide emissions. A study of sidewalk and transit investments in Seattle neighborhoods found vehicle travel reductions of 6 to 8% and CO2 emission reductions of 1.3 to 2.2% [14]Sidewalk with bike path See also: Road traffic safety
Research commissioned for the Florida Department of Transportation, published in 2005, found that, in Florida, the Crash Reduction Factor (used to estimate the expected reduction of crashes during a given period) resulting from the installation of sidewalks averaged 74%.[15] Research at the University of North Carolina for the U.S. Department of Transportation found that the presence or absence of a sidewalk and the speed limit are significant factors in the likelihood of a vehicle/pedestrian crash. Sidewalk presence had a risk ratio of 0.118, which means that the likelihood of a crash on a road with a paved sidewalk was 88.2 percent lower than one without a sidewalk. "This should not be interpreted to mean that installing sidewalks would necessarily reduce the likelihood of pedestrian/motor vehicle crashes by 88.2 percent in all situations. However, the presence of a sidewalk clearly has a strong beneficial effect of reducing the risk of a 'walking along roadway' pedestrian/motor vehicle crash." The study does not count crashes that happen when walking across a roadway. The speed limit risk ratio was 1.116, which means that a 16.1-km/h (10-mi/h) increase in the limit yields a factor of (1.116)10 or 3.[16]
The presence or absence of sidewalks was one of three factors that were found to encourage drivers to choose lower, safer speeds.[17]
On the other hand, the implementation of schemes which involve the removal of sidewalks, such as shared space schemes, are reported to deliver a dramatic drop in crashes and congestion too, which indicates that a number of other factors, such as the local speed environment, also play an important role in whether sidewalks are necessarily the best local solution for pedestrian safety.[18]
In cold weather, black ice is a common problem with unsalted sidewalks. The ice forms a thin transparent surface film which is almost impossible to see, and so results in many slips by pedestrians.
Riding bicycles on sidewalks is discouraged since some research shows it to be more dangerous than riding in the street.[19] Some jurisdictions prohibit sidewalk riding except for children. In addition to the risk of cyclist/pedestrian collisions, cyclists face increase risks from collisions with motor vehicles at street crossings and driveways. Riding in the direction opposite to traffic in the adjacent lane is especially risky.[20]
Since residents of neighborhoods with sidewalks are more likely to walk, they tend to have lower rates of cardiovascular disease, obesity, and other health issues related to sedentary lifestyles.[21] Also, children who walk to school have been shown to have better concentration.[22]Native Americans busking at Orchard Road, Singapore
Some sidewalks may be used as social spaces with sidewalk cafes, markets, or busking musicians, as well as for parking for a variety of vehicles including cars, motorbikes and bicycles.
Contemporary sidewalks are most often made of concrete in the United States and Canada, while tarmac, asphalt, brick, stone, slab and (increasingly) rubber are more common in Europe.[23] Different materials are more or less friendly environmentally: pumice-based trass, for example, when used as an extender is less energy-intensive than Portland cement concrete or petroleum-based materials such as asphalt or tar-penetration macadam). Multi-use paths alongside roads are sometimes made of materials that are softer than concrete, such as asphalt.
In the 19th century and early 20th century, sidewalks of wood were common in some North American locations. They may still be found at historic beach locations and in conservation areas to protect the land beneath and around, called boardwalks.
Brick sidewalks are found in some urban areas, usually for aesthetic purposes. Brick sidewalk construction usually involves the usage of a mechanical vibrator to lock the bricks in place after they have been laid (and/or to prepare the soil before laying). Although this might also be done by other tools (as regular hammers and heavy rolls), a vibrator is often used to speed up the process.
Stone slabs called flagstones or flags are sometimes used where an attractive appearance is required, as in historic town centers. In other places, pre-cast concrete slabs (called paving slabs or, less correctly, paving stones) are used. These may be colored or textured to resemble stone.Freshly laid concrete sidewalk, with horizontal strain-relief grooves faintly visible
In the United States and Canada, the most common type of sidewalk consists of a poured concrete ribbon, examples of which from as early as the 1860s can be found in good repair in San Francisco, and stamped with the name of the contractor and date of installation.[citation needed] When quantities of Portland cement were first imported to the United States in the 1880s, its principal use was in the construction of sidewalks.[24]
Today, most sidewalk ribbons are constructed with cross-lying strain-relief grooves placed or sawn at regular intervals typically 5 feet (1.5 m) apart. This partitioning, an improvement over the continuous slab, was patented in 1924 by Arthur Wesley Hall and William Alexander McVay, who wished to minimize damage to the concrete from the effects of tectonic and temperature fluctuations, both of which can crack longer segments.[25] The technique is not perfect, as freeze-thaw cycles (in cold-weather regions) and tree root growth can eventually result in damage which requires repair.
In highly variable climates which undergo multiple freeze-thaw cycles, the concrete blocks will be separated by expansion joints to allow for thermal expansion without breakage. The use of expansion joints in sidewalks may not be necessary, as the concrete will shrink while setting.[26]
In the United Kingdom, Australia and France suburban sidewalks are most commonly constructed of tarmac. In urban or inner-city areas sidewalks are most commonly constructed of slabs, stone, or brick depending upon the surrounding street architecture and furniture.