Lifeboat Foundation

Miniaturized semiconductor devices with energy harvesting features have paved the way to wearable technologies and sensors. Although thermoelectric systems have attractive features in this context, the ability to maintain large temperature differences across device terminals remains increasingly difficult to achieve with accelerated trends in device miniaturization. As a result, a group of scientists in applied sciences and engineering has developed and demonstrated a proposal on an architectural solution to the problem in which engineered thin-film active materials are integrated into flexible three-dimensional (3D) forms.

The approach enabled efficient thermal impedance matching, and multiplied heat flow through the harvester to increase efficient power conversion. In the study conducted by Kewang Nan and colleagues, interconnected arrays of 3D thermoelectric coils were built with microscale ribbons of the active material monocrystalline silicon to demonstrate the proposed concepts. Quantitative measurements and simulations were conducted thereafter to establish the basic operating principles and key design features of the strategy. The results, now published on Science Advances, suggested a scalable strategy to deploy hard thermoelectric thin-films within energy harvesters that can efficiently integrate with soft material systems including human tissue to develop wearable sensors in the future.

Thermoelectric devices provide a platform to incorporate ubiquitous thermal gradients that generate electrical power. To operate wearable sensors or the “Internet of Things” devices, the temperature gradient between the surrounding environment and the human body/inanimate objects should provide small-scale power supplies. Continued advances in the field focus on aggressive downscaling of power requirements for miniaturized systems to enhance their potential in thermoelectric and energy harvesting applications. Integrated processors and radio transmitters for example can operate with power in the range of subnanowatts, some recent examples are driven via ambient light-based energy harvesting and endocochlear potential. Such platforms can be paired with sensors with similar power to enable distributed, continuous and remote environmental/biochemical monitoring.

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Purdue University researchers have developed a new flexible and translucent base for silicon nanoneedle patches to deliver exact doses of biomolecules directly into cells and expand observational opportunities.

“This means that eight or nine silicon nanoneedles can be injected into a single cell without significantly damaging a cell. So we can use these nanoneedles to deliver biomolecules into cells or even tissues with minimal invasiveness,” said Chi Hwan Lee, an assistant professor in Purdue University’s Weldon School of Biomedical Engineering and School of Mechanical Engineering.

A surgeon performs surgery on the back of a hand of a patient who has melanoma. Purdue researchers are developing a new flexible and translucent base for silicon patches to deliver exact doses of biomolecules directly into cells and expand observational opportunities. The researchers say skin cancer could be one of the applications for the patches.

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This year, more candidates with degrees in science, medicine and engineering ran for Congress than ever before. Of the nearly two-dozen new candidates in this crop, at least seven won seats in the House of Representatives.

This year, scientists, doctors and engineers ran for office like never before. Here’s how they did.

Scientists in Japan have developed the world’s first test that can detect cancers in patient urine samples. The breakthrough technology by Japanese researchers from engineering firm Hitachi has been in development for two years and it may be made available by 2020.

According to Agence France-Presse, the research team will work with Nagoya University to analyze 250 urine samples to check for breast, colon, and childhood forms of the disease in central Japan. The experiments will begin this month and end in September.

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The kilogram is one of the most important and widely used units of measure in the world — unless you live in the US. For everyone else, having an accurate reading on what a kilogram is can be vitally important in fields like manufacturing, engineering, and transportation. Of course, a kilogram is 1,000 grams or 2.2 pounds if you want to get imperial. That doesn’t help you define a kilogram, though. The kilogram is currently controlled by a metal slug in a French vault, but its days of importance are numbered. Scientists are preparing to re define the kilogram using science.

It’s actually harder than you’d expect to know when a measurement matches the intended standard, even when it’s one of the well–define d Systéme International (SI) units. For example, the meter was originally define d in 1793 as one ten-millionth the distance from the equator to the north pole. That value was wrong, but the meter has since been re define d in more exact terms like krypton-86 wavelength emissions and most recently the speed of light in a vacuum. The second was previously define d as a tiny fraction of how long it takes the Earth to orbit the sun. Now, it’s pegged to the amount of time it takes a cesium-133 atom to oscillate 9,192,631,770 times. Again, this is immutable and extremely precise.

That brings us to the kilogram, which is a measurement of mass. Weight is different and changes based on gravity, but a kilogram is always a kilogram because it comes from measurements of density and volume. The definition of the kilogram is tied to the International Prototype of the Kilogram (IPK, see above), a small cylinder of platinum and iridium kept at the International Bureau of Weights and Measures in France. Scientists have created dozens of copies of the IPK so individual nations can standardize their measurements, but that’s a dangerous way to go about it. If anything happened to the IPK, we wouldn’t have a standard kilogram anymore.

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High in the Andes Mountains, conservators are testing traditional methods for strengthening adobe buildings.

The bell tower of the church of Santiago Apóstol in Kuño Tambo, Peru. Built by the Spanish in 1681, it has been weakened by earthquakes, but traditional techniques are helping with its restoration. Credit Credit Angela Ponce for The New York Times.

Solid-liquid filtration is a ubiquitous process found in industrial and biological systems. Although implementations vary widely, almost all filtration systems are based on a small set of fundamental separation mechanisms, including sieve, cross-flow, hydrosol, and cyclonic separation. Anatomical studies showed that manta rays have a highly specialized filter-feeding apparatus that does not resemble previously described filtration systems. We examined the fluid flow around the manta filter-feeding apparatus using a combination of physical modeling and computational fluid dynamics. Our results indicate that manta rays use a unique solid-fluid separation mechanism in which direct interception of particles with wing-like structures causes particles to “ricochet” away from the filter pores. This filtration mechanism separates particles smaller than the pore size, allows high flow rates, and resists clogging.

Several fundamental mechanisms for solid-fluid separation have been described in the biological and engineering literature, including sieve (1, 2), cross-flow (3–6), hydrosol , and cyclonic separation. Sieve filtration passes a mixture of particles and fluid through a structure with regularly sized pores, causing the particles to be retained while the fluid is drained. Although effective, sieve filters must have pore sizes smaller than the particle size, and they inevitably clog in use (2, 8, 9). Cross-flow filtration is similar to sieving, except that the incoming flow runs parallel rather than perpendicular to the filter. This configuration shears captured particles off the filter’s surface, which reduces but does not eliminate clogging (5, 6). Unlike sieve and cross-flow filters, hydrosol and cyclonic filtration do not require regularly sized pores.

#DidYouKnow : NASA Dawn Mission is the only spacecraft that has ever orbited two worlds beyond Earth. Watch our experts discuss 11 years of scientific discovery, breathtaking imagery and unprecedented feats of engineering from the mission: https://go.nasa.gov/2qlECc9

If you haven’t heard, universities around the world are offering their courses online for free (or at least partially free). These courses are collectively called MOOCs or Massive Open Online Courses.

In the past six years or so, over 800 universities have created more than 10,000 of these MOOCs. And I’ve been keeping track of these MOOCs the entire time over at Class Central, ever since they rose to prominence.

In the past four months alone, 190 universities have announced 600 such free online courses. I’ve compiled a list of them and categorized them according to the following subjects: Computer Science, Mathematics, Programming, Data Science, Humanities, Social Sciences, Education & Teaching, Health & Medicine, Business, Personal Development, Engineering, Art & Design, and finally Science.

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