Author Archives: curiouscat

Updated Black and Decker Codeless Lawn Mower Review

Update: Less than 2 years old the battery can’t even mow 1/2 of what the old lawn mower battery could mow after it was much older. Unfortunately it seem that even my pessimistic expectations were too high. They managed to provide worse battery product after years of breakthroughs in improving batteries. I would recommend avoiding Black and Decker.

Better options: Toro 20360 e-Cycler 20-Inch 36-Volt Cordless Electric Lawn Mower – Earthwise 60120 20-Inch 24-Volt Cordless Electric Lawn Mower

The bag is indeed much better than the old version but it is the only improvement. The other problems I mentioned do indeed continue to annoy as it is used.

My old version of this mower just stopped working and the repair guy said it would cost $250 for a new starter, new battery… So I bought a new one: Black & Decker 19-Inch 24-Volt Cordless Electric Mulching Lawn Mower #CMM1200. He said that the new ones were not as well manufactured. I couldn’t imagine how you could make things worse (it is a simple product and just adopting improvement over the years should be really easy).

But, the starter on this model is horrible. You have to tun this incredibly cheap key in a very poorly designed socket. Fails over 80% of the time. The old model started easily essentially every time. The design was just as you would expect, foolproof. Whatever pointy haired boss approved this design needs to go into another line of work.

The ability of the mower to cope with high grass is very poor – much worse than the previous model. I had a good test at first given the time between my mower breaking and getting the new one. Not often an issue, but still not a good thing.

They had a poor indication of the charge left in the battery previously. They now provide no indication of the charge left. It makes you realize that a poor indication was much better than none.

Battery technology has improved a great deal, and that was one of biggest the weaknesses of the last one. Well they seem to have managed to provide worse battery performance after 5 years of improvement in that technology. Pretty sad.
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All About Circuits

All About Circuits is an online textbook covering electricity and electronics. Topics covered include: Basic Concepts of Electricity’ OHM’s Law; Electrical Safety; Series and Parallel Circuits; Physics of Conductors and Insulators; Solid-State Device Theory; Binary Arithmetic; Logic Gates; Switches; Digital Storage? It is a great resource. Enjoy.

Mycoremediation and its Applications In Oil Spills

The webcast shows a talk by mycologist Paul Stamets on Bioremediation with Fungi (an Excerpt from Mushrooms as Planetary Healers). In response he to the British Petroleum/Halliburton oil spill he posted a message, Fungi Perfecti: the petroleum problem

Various enzymes (from mushroom mycoremediation) breakdown a wide assortment of hydrocarbon toxins.
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My work with Battelle Laboratories, in collaboration with their scientists, resulted in TAH’s (Total Aromatic Hydrocarbons) in diesel contaminated soil to be reduced from 10,000 ppm to < 200 ppm in 16 weeks from a 25% inoculation rate of oyster (Pleurotus ostreatus) mycelium, allowing the remediated soil to be approved for use as landscaping soil along highways. [paper]
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Aged mycelium from oyster mushrooms (Pleurotus ostreatus) mixed in with ‘compost’ made from woodchips and yard waste (50:50 by volume) resulted in far better degradation of hydrocarbons than oyster mushroom mycelium or compost alone.
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Oyster mushrooms producing on oil contaminated soil (1–2% = 10,000–20,000 ppm)… Soil toxicity reduced in 16 weeks to less than ~ 200 ppm, allowing for plants, worms and other species to inhabit whereas control piles remained toxic to plants and worms.
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New crop of mushrooms form several weeks later [after contaminating with oil]. The spores released by these mushrooms have the potential – as a epigenetic response – to pre-select new strains more adaptive to this oil-saturated substrate.
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I proposed in 1994 that we have Mycological Response Teams (MRTs) in place to react to catastrophic events, from hurricanes to oil spills. We need to preposition composting and mycoremediation centers adjacent to population centers
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On a grand scale, I envision that we, as a people, develop a common myco-ecology of consciousness and address these common goals through the use of mycelium. To do so means we need to spread awareness and information. Please spread the word of mycelium.

A Breakthrough Cure for Ebola

A breakthrough cure for Ebola By Steven Salzberg

Last week, in what may be the biggest medical breakthrough of its kind in years, a group of scientists published results in The Lancet describing a completely new type of anti-viral treatment that appears to cure Ebola. They report a 100% success rate, although admittedly the test group was very small, just 4 rhesus monkeys.

This is a breakthrough not only because it may give us a cure for an uncurable, incredibly nasty virus, but also because the same method might work for other viruses, and because we have woefully few effective antiviral treatments. We can treat bacterial infections with antibiotics, but for most viruses, we have either a vaccine or nothing. And a vaccine, wonderful as it is, doesn’t help you after you’re already infected.

The scientists, led by Thomas Geisbert at Boston University, used a relatively new genomics technique called RNA interference to defeat the virus. Here’s how it works.
First, a little background: the Ebola virus is made of RNA, just like the influenza virus. And just like influenza, Ebola has very few genes – only 8. One of its genes, called L protein, is responsible for copying the virus itself. Two others, called VP24 and VP35, interfere with the human immune response, making it difficult for our immune system to defeat the virus.

Geisbert and his colleagues (including scientists from Tekmira Pharmaceuticals and USAMRIID) designed and synthesized RNA sequences that would stick to these 3 genes like glue. How did they do that? We know the Ebola genome’s sequence – it was sequenced way back in 1993. And we know that RNA sticks to itself using the same rules that DNA uses. This knowledge allowed Geisbert and colleagues to design a total of 10 pieces of RNA (called “small interfering RNA” or siRNA) that they knew would stick to the 3 Ebola genes. They also took care to make sure that their sticky RNA would not stick to any human genes, which might be harmful. They packaged these RNAs for delivery by inserting them into nanoparticles that were only 81-85 nanometers across.
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Sub $100 Tablet in 2011

I must admit I am skeptical. If it happens this looks very cool.

One Laptop Per Child Revamps Tablet Plans

On Thursday the foundation announced a partnership with chip maker Marvell to collaborate on a sleek and cheap touch-screen tablet for developing-world school children, a device it now plans to launch at the Consumer Electronics Show in January 2011 for less than $100. One Laptop Per Child (OLPC) says that’s close to two years ahead of its scheduled release for the so-called XO-3, the long-awaited upgrade to the non-profit’s XO, the so-called “hundred-dollar laptop” launched in 2007.
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The first XO, for instance, never reached its price target of $100; it now sells for $172. About 2 million of the devices have been sold–a significant achievement for a small nonprofit, but far less than its initial projections. And a flashy double touch-screen model known as the XO-2 was quietly scrapped last year when OLPC decided it couldn’t be made cheaply enough.
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As for Marvell, the partnership with OLPC could lend more credibility to its Moby tablet, which is designed for educational uses like electronic textbooks. OLPC is also building Marvell’s chips into an upgraded form of its XO, known as the XO 1.75, later this year. “When we first met Nicholas, we were very moved by his leadership,” says Dai Weili, Marvell’s chief operating office. “We’ve got the cost structure, feature capability and scalability to support his vision for many years to come.”

USA Science And Engineering Kavli Video Contest

Do you think Science is cool? Do you want to share your passion for science with others? Here is your chance to inspire thousands of people to be more curious, and to care about science & engineering the way you do: create a short video that explores the question “Why is Science Cool?”

We are seeking videos that are creative, surprising, and “contagious” in terms of spreading your enthusiasm about science to others. Videos might explore a scientific concept, show us the wonders of nature, give us a glimpse into the future, show us what scientific discovery has done for us in the past or will do for us in the future, introduce us to a great scientist or engineer, tell us why you think science is so cool or simply show us why we should care about science and/or engineering.

1st prize: $1,000 (to the school or science club); plus $500 electronics gift certificate for the student (or student group); plus a travel stipend to travel to Washington DC for the Expo!

In addition, the winning videos will be screened during the USA Science & Engineering Festival Expo on the National Mall in Washington DC on October 23 and 24, 2010 and at other key Festival events.

Find out how to submit a video.

Home Engineering: Bird Feeder That Automatically Takes Photos When Birds Feed

During a trip to the Smithsonian last week I found this great home engineering project. Kayty Himelstein and Amy Darr were frustrated: birds came to their bird feeder while they were away at school, so the girls never got to see them. They decided to build a bird feeder that automatically takes pictures of all the birds that came to the feeder. I believe, they used Lego Mindstorms as part of building it.

Top Kill Effort to Stop Oil Leak Initially Working

‘Top kill’ stops gulf oil leak for now, official says

Engineers have at least temporarily stopped the flow of oil and gas into the Gulf of Mexico from a gushing BP well, the federal government’s top oil-spill commander, U.S. Coast Guard Adm. Thad Allen, said Thursday morning.

The “top kill” effort, launched Wednesday afternoon by industry and government engineers, had pumped enough drilling fluid to block oil and gas spewing from the well, Allen said. The pressure from the well was very low, he said, but persisting. The top kill effort is not complete, officials caution.

Once engineers had reduced the well pressure to zero, they were to begin pumping cement into the hole to entomb the well. To help in that effort, he said, engineers also were pumping some debris into the blowout preventer at the top of the well.

Update: The top kill effort failed. BP is now trying to capture the oil as it spills into the water with a funnel like device.

Essentials of Genetics Website Reference

Scitable is a science library and personal learning tool on genetics developed by Nature. I must admit I am against the closed science stance Nature normally supports. But this is a good effort on their part at actually talking advantage of the internet to openly promote science. I imagine Nature will eventually more and more move toward supporting open science.

The website has a library of over 200 faculty-written, peer-reviewed articles on core concepts in genetics, plus a video-based online primer called Essentials of Genetics, glossaries, spotlights on key issues, and lots more high quality faculty and student resources.

Scitable is a great place to research and learn more about genetics topics such as diseases, evolution, genetics and society.

Google Prediction API

This looks very cool.

The Prediction API enables access to Google’s machine learning algorithms to analyze your historic data and predict likely future outcomes. Upload your data to Google Storage for Developers, then use the Prediction API to make real-time decisions in your applications. The Prediction API implements supervised learning algorithms as a RESTful web service to let you leverage patterns in your data, providing more relevant information to your users. Run your predictions on Google’s infrastructure and scale effortlessly as your data grows in size and complexity.

Accessible from many platforms: Google App Engine, Apps Script (Google Spreadsheets), web & desktop apps, and command line.

The Prediction API supports CSV formatted training data, up to 100M in size. Numeric or unstructured text can be sent as input features, and discrete categories (up to a few hundred different ones) can be provided as output labels.

Uses:
Language identification
Customer sentiment analysis
Product recommendations & upsell opportunities
Diagnostics
Document and email classification
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