STT-MRAM is capable of high-speed operation and consumes very little power as it retains data even when the power is off. Because of these features, STT-MRAM is gaining traction as the next-generation technology for applications such as embedded memory, main memory and logic. Three large semiconductor fabrication plants have announced that risk mass-production will begin in 2018.

As memory is a vital component of computer systems, handheld devices and storage, its performance and reliability are of great importance for green energy solutions.

The current capacity of STT-MRAM is ranged between 8Mb-40Mb. But to make STT-MRAM more practical, it is necessary to increase the memory density. The team at the Center for Innovative Integrated Electronic Systems (CIES) has increased the memory density of STT-MRAM by intensively developing STT-MRAMs in which magnetic tunnel junctions (MTJs) are integrated with CMOS. This will significantly reduce the power-consumption of embedded memory such as cache and eFlash memory.

MTJs were miniaturized through a series of process developments. To reduce the memory size needed for higher-density STT-MRAM, the MTJs were formed directly on via holes — small openings that allow a conductive connection between the different layers of a semiconductor device. By using the reduced size memory cell, the research group has designed 128Mb-density STT-MRAM and fabricated a chip.

In the fabricated chip, the researchers measured a write speed of subarray. As a result, high-speed operation with 14ns was demonstrated at a low power supply voltage of 1.2 V. To date, this is the fastest write speed operation in an STT-MRAM chip with a density over 100Mb in the world.

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Losing a limb due to trauma, cancer, or poor circulation can result in phantom limb and stump pain in upwards of 75 percent of amputees in the United States. Primary TMR – the rerouting of nerves cut during amputation into surrounding muscle – greatly reduces phantom limb and residual limb pain, as reported in recent publications by Dr. Ian Valerio, division chief of Burn, Wound and Trauma in Ohio State’s Department of Plastic and Reconstructive Surgery, and Dr. J. Byers Bowen, a former resident who is now in private practice. Their latest work featured in the January 2019 issue of Plastic and Reconstructive Surgery describes how to perform this technique in below-the-knee amputations.

TMR was first developed to allow amputees better control of upper limb prosthetics. Traditionally doctors perform the surgery months or years after the initial amputation. When surgeons discovered the procedure also improves certain causes of pain, they started using it to treat disorganized nerve endings called symptomatic neuromas and/or phantom limb pain.

In this paper, Valerio and Bowen provide a detailed description of TMR in below-the-knee amputees and document the benefits of primary TMR for preventing pain.

“This paper provides a blueprint for improving patient outcomes and quality of life following amputation,” said Dr. K. Craig Kent, dean of The Ohio State University College of Medicine.

Over the course of three years, the surgeons performed 22 TMR surgeries on below-the-knee amputees, 18 primary and four secondary. None of the patients have developed symptomatic neuromas and only 13 percent of patients who received primary TMR reported having pain six months later.

“A significant amount of pain in amputees is caused by disorganized nerve endings, i.e. symptomatic neuromas, in the residual limb. They form when nerves are severed and not addressed, thus they have nowhere to go,” Valerio said. “Attaching those cut nerve endings to motor nerves in a nearby muscle allows the body to re-establish its neural circuitry. This alleviates phantom and residual limb pain by giving those severed nerves somewhere to go and something to do.”

Valerio said patients who’ve had TMR significantly reduce or sometimes stop using narcotics and other nerve pain related medications, which can greatly improve their quality of life.

“TMR has been shown to reduce pain scores and multiple types of pain via a variety of validated pain surveys. These findings are the first to show that surgery can greatly reduce phantom and other types of limb pain directly,” Valerio said.

Bowen added that upper extremity amputees are better able to use and control their prosthetics in addition to their improved pain outcomes. He said, “TMR allows for more individual muscle unit firings through the patient’s thoughts. It provides for better intuitive control resulting in more refined functional movements and more degrees of motion by an advanced prosthetic.”

The researchers believe primary TMR is a reliable technique to prevent the development of disorganized nerve endings and to reduce phantom and other limb pain in all types of amputations. When done at the time of initial amputation, there is minimal health risk and recovery is similar to that of traditional amputation surgery.

Surgeons perform TMR routinely at Ohio State, with primary TMR as the standard of care for most orthopedic-based traumatic and oncologic amputations. Valerio lectures and trains surgeons around the world on the primary TMR technique in an effort to make it a global best practice.

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We have known for the past 20 years that the Universe is expanding at an ever accelerating rate. The explanation is the “dark energy” that permeates it throughout, pushing it to expand. Understanding the nature of this dark energy is one of the paramount enigmas of fundamental physics.

It has long been hoped that string theory will provide the answer. According to string theory, all matter consists of tiny, vibrating “stringlike” entities. The theory also requires there to be more spatial dimensions than the three that are already part of everyday knowledge. For 15 years, there have been models in string theory that have been thought to give rise to dark energy. However, these have come in for increasingly harsh criticism, and several researchers are now asserting that none of the models proposed to date are workable.

In their article, the scientists propose a new model with dark energy and our Universe riding on an expanding bubble in an extra dimension. The whole Universe is accommodated on the edge of this expanding bubble. All existing matter in the Universe corresponds to the ends of strings that extend out into the extra dimension. The researchers also show that expanding bubbles of this kind can come into existence within the framework of string theory. It is conceivable that there are more bubbles than ours, corresponding to other universes.

The Uppsala scientists’ model provides a new, different picture of the creation and future fate of the Universe, while it may also pave the way for methods of testing string theory.

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Researchers from the Dauphin Island Sea Lab and the Mission-Aransas National Estuarine Research Reserve teamed up for a two-year study to document the problem along the Gulf of Mexico shorelines. Their findings are documented in the publication, Accumulation and distribution of marine debris on barrier islands across the northern Gulf of Mexico, in ScienceDirect’s Marine Pollution Bulletin.

From February 2015 to August of 2017, the researchers kept tabs on marine debris that washed up on the shoreline every month at 12 different sites on nine barrier islands from North Padre Island, Texas to Santa Rosa, Florida. The trash was sorted by type, frequency, and location.

The most shocking discovery was that ten times more trash washes up on the coast of Texas than any of the other Gulf states throughout the year.

Most of the trash, 69 to 95 percent, was plastic. The plastic items included bottles and bottle caps, straws, and broken pieces of plastic. Researchers also cited that more trash washed ashore during the spring and summer. This could be because more people are outside and on the water during this time.

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This band of recurring weather, first described by scientists in 1971, is called the Madden-Julian Oscillation. It has profound effects on weather in distant places, including the United States. Atmospheric scientists have long studied how the Madden-Julian Oscillation modulates extreme weather events across the globe, from hurricanes to floods to droughts.

As human activities cause the Earth’s temperature to increase, reliable, well-studied weather patterns like the Madden-Julian Oscillation will change too, say researchers at Colorado State University.

Eric Maloney, professor in the Department of Atmospheric Science, has led a new study published in Nature Climate Change that attributes future changes in the behavior of the Madden-Julian Oscillation to anthropogenic global warming. Maloney and co-authors used data from six existing climate models to synthesize current views of such changes projected for the years 2080-2100.

Their analysis reveals that while the Madden-Julian Oscillation’s precipitation variations are likely to increase in intensity under a warmer climate, wind variations are likely to increase at a slower rate, or even decrease. That’s in contrast to the conventional wisdom of a warming climate producing a more intense Madden-Julian Oscillation, and thus an across-the-board increase in extreme weather.

“In just looking at precipitation changes, the Madden-Julian Oscillation is supposed to increase in strength in a future climate,” Maloney said. “But one of the interesting things from our study is that we don’t think this can be generalized to wind as well.”

Atmospheric science relies on weather patterns like the Madden-Julian Oscillation to inform weather prediction in other areas of Earth. For example, atmospheric rivers, which are plumes of high atmospheric water vapor that can cause severe flooding on the U.S. west coast, are strongly modulated by certain phases of the Madden-Julian Oscillation.

According to Maloney’s work, the Madden-Julian Oscillation’s impact on remote areas may gradually decrease. Degradation in the oscillation’s wind signal may thus diminish meteorologists’ ability to predict extreme weather events. In particular, preferential warming of the upper troposphere in a future, warmer climate is expected to reduce the strength of the Madden-Julian Oscillation circulation.

Maloney and colleagues hope to continue studying the Madden-Julian Oscillation using a broader set of climate models to be used in the next Intergovernmental Panel on Climate Change assessment.

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