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Friday, May 29, 2015

Cartoons: How the tune changes

Time passes, things happen and the tune changes. Then it changes again. As the philosophers say: the only constant is change.
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image: cartoon by Mike Luckovich
Mike Luckovich, The Week
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Last year it was the 'pollen vortex', this year it's the 'pollen tsunami'. Call it what you will pollen counts have been rising yearly. or so the reporters say (unable to find numbers to support that). GlobalChange.gov has a good graph on observed CO emissions vs. Temperature.
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image: cartoon by Tom Toles
Tom Toles, The Week

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Last week it was Deflategate, this week it's FIFA corruption charges.
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image: cartoon by Bob Gorrell
Bob Gorrell, The Week

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This cartoon is, for me, self-evident.
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image: cartoon by Steve Kelley
Steve Kelley, The Week

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-- Marge


Wednesday, May 27, 2015

DIY DIWhy

Here are some DIY projects that went wrong or just don't work. You'll see why.

Viralnova coined the term DIWhy. Here's a link to their about page and a sample from Forget DIYs, These Are 2014's 20 Best DI-'Why?' Projects.
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image: photo of furry fridge
Furry Fridge (Imgur via Reddit), ViralNova
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The venerable Popular Mechanics has this article: There, I Fixed It: 10 Hilariously Bad Home DIY Projects.
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image: temporary repair, West Virginia State Dept of Transportation gas station
West Virginia State Dept of Transportation gas station, Popular Mechanics
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Then there's the world that postgrads live in. This is from When DIY Goes Wrong…Or Right (24 Photos).
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image: photo of couch fix
Couch Fixed, Post Grad Problems
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-- Marge


Friday, May 22, 2015

Cartoons: Bankers and Letterman

The cartoons this week are overwhelmingly about Hillary and Jeb, the Middle East and ISIS, and college debt; here are three that aren't.

With chickens and their eggs cage-free is good; with bankers not so much. And to think I store my modest funds in one.
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image: cartoon by Mike Luckovich
Mike Luckovich, The Week
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Another example of the Congress' and the GOP's mixed messages, to say the least.
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image: cartoon by Pat Bagley
Pat Bagley, The Week
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Letterman has left the Late Show, but his Stupid Pet Tricks live on--check YouTube. Here's a tricky word play for you.
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image: cartoon by Walt Handelsman
Walt Handelsman, The Week
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-- Marge


Wednesday, May 20, 2015

DIY: open up your world

image: kids laughing together
Kids, Cincinnati Enquirer
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With so much prejudice, even hate, filling the news now, isn't it time to step back and decide what you want your world to look like and be? An all-white or all-black or all-brown world is NOT a viable solution. Such a solution would entail either shutting yourself off from the majority of humanity in a strongly gated, highly exclusive community or mass genocide. Seems to me the better answer is to teach yourself how to deal with diversity.

To exercise prejudice may be hardwired into humans, as Morgan Freeman points out in the video below--it's a my tribe vs. your tribe mindset. Seems to me it's time for us to outgrow the tribal mindset. As Akhenaten (Egyptian Pharaoh (-1354 BC) said:
True wisdom is less presuming than folly. The wise man doubts often, and changes his mind; the fool is obstinate, and doubts not; he knows all things but his own ignorance.

The video (granted, the study is of mice) here shows that simply associating with someone different opens the door to empathy and ultimately a world with more tolerance.
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The study referred to in the video is reported in Rodent empathy is environmental and not genetic by the Washington Post. The study itself is available at eLife.

Cindy Krantz in the Cincinnati Enquirer wrote in 2000 about Preparing kids for a multicultural world. In her article she breaks down the demographics then. For an analysis of demographics in the U.S. in 2015, check out the Wikipedia article.
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image: graph of U.S. demographics in 1990
U.S. demographics in 1990, Cincinnati Enquirer
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Kids in kindergarten mingle happily with other cultures. Then the prejudices of their parents take over. We can change that.

Stepping down from my soapbox now.

-- Marge




Monday, May 18, 2015

Science: the flux we live in

image: illustration using SGR 1745-525
Magnetar SGR 1745-525, NASA-Chandra

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On May 16th NASA issued a press release reporting that a magnetar near a supermassive black hole delivers surprises. The black hole is the one at the center of the Milky Way; the surprise is that
the amount of X-rays from SGR 1745-2900 is dropping more slowly than other previously observed magnetars, and its surface is hotter than expected.
My interest was piqued. On researching the literature about Magnetars, I found this
1979 discovery
On March 5, 1979, a few months after the successful dropping of satellites into the atmosphere of Venus, the two Soviet spacecraft that were then drifting through the Solar System were hit by a blast of gamma radiation at approximately 10:51 EST. This contact raised the radiation readings on both the probes from a normal 100 counts per second to over 200,000 counts a second, in only a fraction of a millisecond.
This burst of gamma rays quickly continued to spread. Eleven seconds later, Helios 2, a NASA probe, which was in orbit around the Sun, was saturated by the blast of radiation. It soon hit Venus, and the Pioneer Venus Orbiter's detectors were overcome by the wave. Seconds later, Earth received the wave of radiation, where the powerful output of gamma rays inundated the detectors of three U.S. Department of Defense Vela satellites, the Soviet Prognoz 7 satellite, and the Einstein Observatory. Just before the wave exited the Solar System, the blast also hit the International Sun-Earth Explorer. This extremely powerful blast of gamma radiation constituted the strongest wave of extra-solar gamma rays ever detected; it was over 100 times more intense than any known previous extra-solar burst. Because gamma rays travel at the speed of light and the time of the pulse was recorded by several distant spacecraft as well as on Earth, the source of the gamma radiation could be calculated to an accuracy of about 2 arcseconds. The direction of the source corresponded with the remnants of a star that had gone supernova around 3000 B.C.E. It was in the Large Magellanic Cloud and the source was named SGR 0525-66, the event itself was named GRB 790305b, the first observed SGR megaflare.
From another section of the Wikipedia article we learn that "magnetars are around 20 kilometres (12 mi) in diameter and have a greater mass than the Sun." Despite this minute size in comparison to other celestial bodies, the burst of radiation raised the radiation reading from the normal 100 count per second to over 200,000 counts per second in a timeframe of milliseconds when detected by the Soviet probes. None of the radiation is reported to have been detected within Earth's atmosphere.

This is a tale of only one magnetar event. "As of November 2013, 21 magnetars are known, with five more candidates awaiting confirmation." reports Wikipedia.

What I wonder is how is life on Earth would be affected if such radiation penetrated Earth's atmosphere. The wave passed through the solar system at the speed of light, too fast for our bodies to detect and react. But the brain works with electricity, which is in the same realm as solar and other radiation. This EPA page gives a good summary of types of radiation.

If magnetar and similar radiation events affect our brains, how? Mentally? Emotionally? An image that comes to mind is the event following contact with the monolith in 2001: A Space Odyssey: an ape's discovery of using a tool. Don't get me wrong, I'm not saying we should walk around wearing tin-foil helmets, but I am asking if historical and social events are sometimes triggered by the celestial flux we live in.
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image: screenshot from 2001: A Space Odyssey
Discovery, 2001: A Space Odyssey
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-- Marge


Friday, May 15, 2015

Cartoons: sellouts and those clueless

Sometimes we sellout to gain money or security or even love; sometimes we don't know we're selling out 'til it's over. Here are some examples.

Picasso didn't sellout, but the art world has. The latest price is $179 million dollars.
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image: cartoon by Steve Breen
Steve Breen, The Week
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It's beginning to look like the Democratic Party is putting all of it's eggs in one basket--Hillary. Is this a sellout or are they just clueless?
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image: cartoon by Michael Ramirez
Michael Ramirez, The Week
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At the risk of offending my religious readers, my view of religion is that it has for centuries sold out our spirituality. There I said it.
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image: cartoon by Mike Luckovich
Mike Luckovich, The Week
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Drone warfare is still war. Has war been declared? No, but the U.S. Congress approves of the drone strikes.
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image: cartoon by Bill Day
Bill Day, The Week
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-- Marge


Wednesday, May 13, 2015

DIY: sewing your own fashion

image: Vogue pattern 8806
Vogue pattern 8806, Sewing Patterns
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Sewing can be one of the most exasperating endeavors I've encountered--can't tell you how many times I've had to re-do what I just did because I did it backward. That said, in today's retail clothing market, sometimes sewing a garment yourself is about the only way you can find/afford something unique.
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image: Burda pattern 8108
Burda pattern 8108, Sewing Patterns
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Probably the single most common error I make when putting together a sewing project is selecting an inappropriate fabric or print to go with the pattern.  It's best to look at the garment illustration on the pattern envelope carefully and heed the fabric suggestions on the back, unless you have a very clear idea of the look you want to create. Sewing Patterns has a good selection of patterns.

If you're new to sewing, there's a lot to learn. Getting to the stage where you can put together a Vogue Couture pattern may take years. There is a Very Easy Vogue collection that has many desirable designs and suits beginners' skills, such as the one below. While it's always best to buy the size that fits your measurements, in my experience Simplicity and McCalls patterns feel small for the measurements given.
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image: Very Easy Vogue pattern 9115
Very Easy Vogue pattern 9115, Sewing Patterns
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A good guide is essential; one that I've used so much it's falling apart is Simplicity Sewing Book (This links to a revised version at Amazon).

For me, one of the most pleasurable aspects of sewing is shopping for and handling fabrics. There are excellent deals and large selections online (Online Fabric Store slider), but you really should go to a local fabric store to get a sense of how light or heavy, firm or not firm, stiff or pliable--called the hand--a fabric is.

If you really don't want to open this can of worms, fulfilling as it can be, and would rather let someone else do the handiwork, take a look at sites like Etsy Clothing, ArtFire, and Rebels Market. There's a list of Etsy alternatives at Business News Daily.

-- Marge


Monday, May 11, 2015

Politics and polls: boycotting the election

This idea behind a cartoon posted Friday has been haunting me.
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image: cartoon by Gary Varvel
Gary VarvelThe Week
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What if, because of the current state of elections--influence by big money and mind-searing partisanship, people decide that the elections are just not worth their time. Or what if the more pro-active, but democratically debilitating phenomenon takes place and people as a group make their intention to boycott the election known?

According to one reference, the Pew Research Center, there is now a Party of Nonvoters, consisting of "younger, more racially diverse, more financially strapped" people. With the increasing gap between the monied 1% and and the rest of us, the ranks of the financially strapped is likely to increase. Pew Research further defines Who Votes, Who Doesn’t, and Why in an article published in 2006. In 2008, when Obama was first elected, CNN reported Number of votes cast set record, but voter turnout percentage didn't. Wikipedia shows that voter turnout in 2008 was "57.5 percent of the eligible voters."

If you look at the polls at Real Clear Politics, the numbers are kind of overwhelming. Being informed in these times can be a fulltime job. For another view of the issues, take a look at I Side With's list of political issues of 2015.

The idea in a democracy is to have your say via one vote. What that one vote says in this political atmosphere is questionable. And sullying the election process with vast amounts of money only makes things worse. In fact throwing money at the election process in an attempt to entice disenfranchised voters to vote seems pretty ineffective.

I found a few voices calling for boycotts of U.S elections. One voice is Election Boycott Advocates. Their byline is "Reject capitalism, demand democracy." Unfortunately the site has strong socialistic overtones. However, this point by the author resonated with me:
Laws restricting third party participation, an elections system that favors money over votes, a two-party system that has no room for any other than the official liberal and conservative ideologies, a Supreme Court that protects the right of billionaires to buy elections and politicians. Why bother, the majority of Americans ask as they throw their hands up in exasperation with a system that just doesn't work for them.
If you search on 'boycott elections' you'll find that a number of countries have done so. Mehrunisa Qayyum at Huffington Post surveys the effectiveness of some boycotts. (Remember, this is an opinion piece.) One boycott in India is particularly interesting, Village sans hospital to boycott polls. The article quotes a village spokesperson,
Leaders have been coming to us but we decided not to vote for any of them this time. It is high time now not to vote. They only give fake promises --Panja Singh, 62, a resident of Jhangola village

-- Marge


Friday, May 08, 2015

Cartoons: going for the humor

Looks to me like cartoonists are getting as snarky as the politicians and news reporters at Fox.  So today's mix is an attempt to find the humor in it all.

Ben Carson, a Tea Party candidate for president in 2016, is not particularly popular with voters, according to poll results at I Side With... Tom Toll's cartoon below paraphrases Ben Carson's statement, quoted from the Huffington Post, "that being gay was a choice "because a lot of people who go into prison go into prison straight -- and when they come out, they're gay. So, did something happen while they were in there? Ask yourself that question." The paraphase makes much more sense to me.
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image: cartoon by Tom Toles
Tom Toles, The Week
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Republican's denial of climate change has made them a laughingstock to many. I Side With asks "Should the government increase environmental regulations to prevent global warming?" You can check the poll answers.
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image: cartoon by Mike Luckovich
Mike Luckovich, The Week
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I hope Chris Christie is unable to overcome Bridgegate--in my eyes, it says clearly what his values and methods are. We're still allowed to laugh, though.
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image: cartoon by Walt Handelsman
Walt Handelsman, The Week
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Unfortunately this cartoon may be too true in depicting what will happen in November 2016, if the political scene continues to unravel.
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image: cartoon by Gary Varvel
Gary Varvel, The Week
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-- Marge


Wednesday, May 06, 2015

DIY: Backyard dressups

If you have a backyard, there are some really cool ideas for making it a better place to hangout in this article by Peggy Wang at BuzzFeed. If you don't have a backyard, my apologies.

Of the 41 ideas Peggy (quoted below) presents, I like these.

Save your pinecones for bedding, which will keep pups and cats out of your plants.
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image: pinecones for bedding
pinecones for bedding, BuzzFeed
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With a few long pieces of wood, you can also use cinder blocks to create an impromptu couch.
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image: improptu couch
improptu couch, BuzzFeed
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Repurpose an old chandelier as a bird feeder.
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image: bird feeder
bird feeder, BuzzFeed
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Spray paint pebbles with glow-in-the-dark paint to light a path at night.
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image: painted pebbles
painted pebbles, BuzzFeed
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This insanely simple rope swing will provide hours of fun.
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rope swing, BuzzFeed
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Most of these don't need instructions; however, weeds may be a problem with the pinecone idea. Here are 8 homemade weed killers from Good Housekeeping.

-- Marge


Monday, May 04, 2015

Using science to date an ancient battle

image: painting of Krishna and Arjun on the chariot, Mahabharata, 18th-19th century, India
Krishna and Arjun on the chariot, Mahabharata, 18th-19th century, India, Wikipedia
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Delving into ancient tales for proof of actual events can be tricky to say the least. But the work of Dr. Naraha Achar used such intriguing methods that I must respect in his results. The basis for this post is a video about finding evidence of a sunken city called Dwaraka (Dvārakā) in ancient India. You can find Dr. Achar's research explained from times 14:30 to 19:40 of this long, sometimes rambling video. Approach with caution: there are suggestions of a conspiracy to cover up archaeological findings and intimations of alien technology.
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Dr. Achar's research is based on a long, complex Sanskrit epic of ancient India called the Mahabharata. B. N. Narahari Achar is professor emeritus at the Department of Physics and Materials Science, University of Memphis. There are several opinions on when the Kurukshetra War, the main event described in the Mahabharata, occurred.

Subhash Kak, professor emeritus at the Department of Electrical & Computer Engineering, Louisiana State University, addresses some of these opinions and how complex the Mahabharata is. Check out this paper by him. In his paper he mentions Dr. Acher's research, saying
Recently, the historian of astronomy Narahari Achar has in unpublished work argued for the date of 3067 BC with an error of a few decades. Achar’s work does not depend on the classical siddhantic ideas which increases its persuasiveness. (Note.9)
Author Stephen Knapp also mentions Dr. Achar's work in his Time Line of Lord Krishna article; but I tend to give his writing a wide berth because of this opening line--"As devotees and followers of the Vedic path..."

Some interesting reading can be found under the topic of Archaeoastronomy. To get an idea of how deep and varied human beliefs are, take a look at Wikipedia's Lists of Deities.

I came across this quote from J.R.R. Tolkien the other day:
All that is gold does not glitter,
not all those who wander are lost;
the old that is strong does not wither,
deep roots are not reached by the frost.

-- Marge

Friday, May 01, 2015

Cartoons: root causes

It's been a tough week around the world, but toughest for Nepal and Cleveland.

So, what is a root cause? According to Wikipedia:
A root cause is an initiating cause of either a condition or a causal chain that leads to an outcome or effect of interest. Commonly, root cause is used to describe the depth in the causal chain where an intervention could reasonably be implemented to improve performance or prevent an undesirable outcome.
The root cause of the current state of Nepal was the earthquake.
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image: cartoon by Steve Sack
Steve Sack, The Week
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I'm not quite sure what the full extent of the root causes of the riots in Cleveland are, but pretty sure most of them are related to racism.  BTW, the driver of the police van has been charged with the depraved-heart murder of Freddie Gray, who was unlawfully arrested for carrying a pocket knife (not a switchblade).
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image: cartoon by Drew Sheneman
Drew Sheneman, The Week
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The root cause for Republicans taking over Congresses in America is in part gerrymandering, although Democrats attempt to do it too. Partisanship and polarization contribute.
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image: cartoon by Glenn McCoy
Glenn McCoy, The Week
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In a time when many legislative bodies are grappling with raising the minimum wage, the Minnesota House has lowered it for tip workers. Seems to me the root cause here is depraved-heart greed.
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image: cartoon by Steve Sack
Steve Sack, The Week

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-- Marge

Wednesday, April 29, 2015

DIY: Emergency toolkits

image: road damage due to earthquake in Nepal
Earthquake, Nepal, The Telegraph
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You never know when a disaster will strike. Best to be prepared. Many agencies have webpages with advice on how to prepare for and withstand the conditions of an emergency. Often these pages deal specifically with natural disasters likely to occur in your area. Here in Anchorage we have the Emergency Management pages, published by the municipality.

Being prepared often means having supplies and a toolkit set aside, 'just in case'. Ready.gov's Basic Disaster Supplies lists some essentials. The site offers a wealth of information on other topics related to preparedness, as well. And you may want to take a moment to reflect on what you would sorely miss (that can be included) if disaster strikes.

DMV.org and Edmunds list emergency supplies for your car. It's surprising how long these lists are. Edmunds notes
Granted, all these items practically necessitate a Ford Excursion to haul them down the road, but a basic version with two roadside flares, a quart of oil, small first aid kit, extra fuses, flashlight, Leatherman Tool (or any other multipurpose tool commonly containing pliers, wire cutters, knife, saw, bottle opener, screwdrivers, files and an awl), tire inflator, rags, pocket knife, pen and paper and a help sign will take up a minimal amount of trunk space.
For your home there's a list at The Family Handyman that makes for interesting reading. As the article says:
A disaster can make you a victim or victor. Luck plays a part, and so does knowing what to do. But nothing matters more than preparation. And that means having the right stuff in your emergency arsenal. Here are our suggestions to help you overcome disasters big and small.

-- Marge


Monday, April 27, 2015

Nepal earthquake: how do cell signals get through?


image: Kathmandu Valley
Kathmandu Valley, UnitingNepal
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Headlines about Nepal praise Google and Facebook for their "collaborative, cellphone-based tools [deployed] over the weekend to help track victims of the earthquake (Washington Post)." My question is--how do the signals get through? The country has experienced an earthquake of magnitude of 7.8 to 8.1 (Wikipedia), so power stations, cell towers, and network infrastructure must have been badly damaged.

Reuters in one of their reports published this map:
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image: map of Nepal earthquake area
Nepal,earthquake map, Reuters
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Currently, there are 6 colocation data centers in Nepal, all of them are located in Kathmandu. This suggests that the cellphone signals are being processed by sites situated elsewhere or by other means.

It looks like Nepal is a magnet for adventurers wanting to trek in the Himalayas. The Mountain Company's FAQ, answering the question "Do mobile/ cell phones work while on trek?," says:
Over the last few years the mobile/ cell phone network has improved significantly in more remote areas of Nepal. There are now cell phone masts installed at Gorakshep so it is possible to get 3G connectivity throughout the entire Everest Base Camp trek.
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In more remote regions of Nepal such as on Dhaulagiri Circuit, Manaslu Circuit and Tsum Valley, Kanchenjunga Circuit, Upper Dolpo treks there will be no mobile/ cell phone coverage. On these trips we send a satellite phone with our groups for communications and our clients are welcome to use for personal calls and SMS texts if they like. 
Also Indian telecom companies are lending a hand.
Indian telecom companies have made calls to Nepal discounted or completely free. Messaging app Viber has made outgoing calls to landlines and mobiles free users of its Viber Out service.
The 2 companies most mentioned in information about cell service in the Nepal area are Nepal Telecom and N Cell (Facebook link, website unavailable).

This is what I could find; I hope you find it useful.

-- Marge


Friday, April 24, 2015

Cartoons: Losing America

Emma Lazarus wrote in 1883:
Not like the brazen giant of Greek fame,
With conquering limbs astride from land to land;
Here at our sea-washed, sunset gates shall stand
A mighty woman with a torch, whose flame
Is the imprisoned lightning, and her name
Mother of Exiles. From her beacon-hand
Glows world-wide welcome; her mild eyes command
The air-bridged harbor that twin cities frame.
"Keep, ancient lands, your storied pomp!" cries she
With silent lips. "Give me your tired, your poor,
Your huddled masses yearning to breathe free,
The wretched refuse of your teeming shore.
Send these, the homeless, tempest-tossed to me,
I lift my lamp beside the golden door!"
Today this is what the GOP would write.
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image: cartoon by Chan Lowe
Chan Lowe, The Week
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Their greed has no bounds.
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image: cartoon by Tom Toles
Tom Toles, The Week
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Meanwhile, those struggling to support themselves struggle more.
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image: cartoon by Mike Luckovich
Mike Luckovich, The Week
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And officials' perceptions that only those with money (read power and influence) and a pale skin color matter continue to become more evident.
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image: cartoon by Nate Beeler
Nate Beeler, The Week
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-- Marge

Wednesday, April 22, 2015

DIY: unusual ways to charge your phone

New ways to charge your phone include a solar panel sculpture that imitates an bonzai; using a heat engine powered by a cup of coffee (or slushie); and riding your bike.  For more ways, check out Hongkiat's 30 Smartphone Chargers You Have Not Seen Before and The Week's 9 strange ways to power your cellphone.  Here are the ones most intriguing to me.

Electree "is delivered in modules which you assemble to create your own tree. This method makes it possible to produce an infinity of different shapes. You can model it according to your wishes and at the same time optimize the orientation of the photovoltaic cells and thus increase its effectiveness."
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image: electree charger
electree
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Epiphany Labs has a kickstarter underway for the onE Puck. According to their Kickstarter page,
The idea behind the Epiphany onE Puck is to use a stirling engine powered solely by heat disparities, such as a hot or cold drink, a candle, ice, etc. These heat sources will provide enough power to the stirling engine to fully charge your cell phone battery. There's nothing new about Stirling engines - they were invented in the early 1800s - but thanks to modern materials and modern electronics, we are able to put them to use in ways that weren't previously possible.
Take time to watch the video, it has some interesting points to make.
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image: Epiphany Labs' oneE Puck charger
Epiphany Labs' oneE Puck, kickstarter
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BikeCharge Dynamo uses straightforward technology, you just use your bike to do the charging.
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image: BikeCharge Dynamo charger
BikeCharge Dynamo, Tigra Sport
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The WakaWaka Power is such a good idea, I had to include it. Their site says to "buy one = give one" in a developing country and they have a well-developed mission.
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image: WakaWaka Power charger
WakaWaka Power
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Here's something we modile users should keep in mind--Pacific Northwest National Library (PNNL) has found that recharging lithium batteries leaves behind microscopic debris. Quoting the article:
An eruption of lithium at the tip of a battery's electrode, cracks in the electrode's body, and a coat forming on the electrode's surface reveal how recharging a battery many times leads to its demise.

-- Marge


Monday, April 20, 2015

Art: murals old and new

Since the time we lived in caves, we've been drawing on the walls. Sometimes Mom gets mad, sometimes the drawings are works of art. The first cave drawings were likely made using charcoal from the fire or stone tools harder than the cave wall. As humans progressed drawing became painting on the walls.

From the Minoans to Renaissance Italians to the present, frescoes have been the preferred method. In frescoes the pigment is laid down on fresh or wet plaster. As a side note, oil paintings on cave walls have been discovered in Afghanistan that date to the  mid-7th century CE (Common Era, also Current Era or Christian Era).
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image: Oil Painting in Bamiyan Valley, Afghanistan
Bamiyan Oil Painting, CAIS
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In more recent times Diego Rivera held the spotlight for murals, as well as a dispute with one patron that resulted in the destruction of his work "Man at the Crossroads." Here's one of his works still available for viewing.
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image: Rivera Mural in the National Palace, Mexico
Rivera Mural in the National Palace, Mexico
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Often murals are considered decorative art, as stated in the article Reassessing Artworks of Ancient Rome. Pictured in the article is the fresco below. It may have been merely decorative (or commemorative) at the time, but has with the passing of time taken on more meaning.
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image: mural of the The Aldobrandini Marriage
The Aldobrandini Marriage, NY Times
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Murals can be political statements, certainly in artist Rivera's case. In my view, street art often qualifies as murals, although they generally are more transitory. Here's a photo essay of The 50 Most Stunning Wall Murals From Around The World. Note that some of Rivera's pieces are included. The image below appears to me to be a statement some might call political.
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image: Berlin art at Oberbaumbrucke Bridge
Berlin art at Oberbaumbrucke Bridge, The Scenic Sidewalk
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-- Marge