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PNNL scientists adjust key metal-organic framework components for intriguing advance to cool buildings

Scientists have known for two decades about a more environmentally friendly way to cool large buildings that is less expensive than conventional cooling systems. The challenge has been making those systems efficient for everyday use.

Targeting the Perfect MOF Cooling Combination

PNNL materials scientist Radha Kishan Motkuri led the study that has been published in the Journal of the American Chemical Society.
Photo: Andrea Starr | PNNL

New research at PNNL, however, shows researchers are moving toward perfecting the technique.

The findings, published in the Journal of the American Chemical Society, show the important molecular understanding and interplay of pore-engineering and refrigerant required to create an improved metal-organic framework (MOF) for adsorption cooling. The researchers, led by PNNL materials scientist Radha Kishan Motkuri, reported a dramatic increase—at least 40 percent—in the efficiency of their pore-engineered MOFs. These metal-ion clusters are porous compounds that take advantage of the adsorption and desorption—the attachment and release—of vapor on and from the surface of refrigerants.

Efficient MOF-cooling systems can now be integrated with conventional refrigeration and air conditioning systems because both use the same refrigerants and evaporator/condenser components. The electric-powered compressor can be turned off when heat is available, like from a solar panel or geothermal resource, to run an MOF-based thermal compressor. Sorption-based cooling systems thus could ease the stress on electricity supplies.

The research builds upon PNNL’s 2017 R&D 100 Award Winning MARCool technology. That innovation created a new class of solid-state cooling technology that operates on wasted heat from power sources such as generators that could lead to significant energy and cost savings in homes, buildings, cars, trucks, navy ships, and industrial processes.

Global energy consumption spike looms

The International Energy Agency, the study notes, estimates that climate control units in buildings consume about 20 percent of the world’s electricity. Global energy demand for space cooling is expected to triple that number by 2050.

Researchers at PNNL have made strides engineering MOFs as adsorbents that can adsorb, or “host,” certain refrigerants. In the JACS-published study, they tested how the common refrigerant, fluorocarbon R134a, performed at the atomic level with MOFs they manipulated to contain a high pore volume and density of open metal centers.

“By increasing these saturation limits, we allow more fluorocarbon to be taken up by the sorbent per cycle of adsorption and desorption based on specified chiller process conditions,” said Motkuri, who for the last 10 years has led material development for various fluorocarbon and water-based adsorption cooling systems. “This increased throughput translates to a 400 percent increase in the theoretical working capacity to cycle between adsorption/desorption state points. Ultimately, correlation of its bulk sorption performance under realistic chiller conditions results in modeled cooling capacities for the expanded MOF, Ni-TPM, that are at least 40 percent larger than that of the parent MOF.”

Seeking better performance

“The study’s researchers embarked to explore which material is the best to pair with the refrigerant to determine the most efficient MOF performance” said Motkuri. “We are engineering these materials to give a better performance,” he added.

“We know that higher adsorbing capacity will result in a more efficient cooling system,” said Pete McGrail, a PNNL Laboratory Fellow who has led the laboratory’s adsorption cooling effort for several years. “This latest research exploits our new ability to custom design MOFs for improved performance in adsorption cooling systems.”

The research was funded by DOE’s Geothermal Technologies Office (GTO). GTO also funded PNNL’s multilayered geothermal Harmonic Adsorption Recuperative Power (HARP) project, which includes materials development that requires a better understanding of the host-guest chemistry to find the best host material. The novel HARP system uses low-grade heat to generate electric power and may help industries reduce costs and increase efficiency. Other funding sources included DOE’s Advanced Photon Source, the National Institute of Standards and Technology, and the U.S. Department of Commerce.

Source: PNNL






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Twist on CRISPR Gene Editing Treats Adult-Onset Muscular Dystrophy in Mice

2020 09 14 DM1 longitudnal muscle

Myotonic dystrophy type I is the most common type of adult-onset muscular dystrophy. People with the condition inherit repeated DNA segments that lead to the toxic buildup of repetitive RNA, the messenger that carries a gene’s recipe to the cell’s protein-making machinery. As a result, people born with myotonic dystrophy experience progressive muscle wasting and weakness and a wide variety of other debilitating symptoms.

CRISPR-Cas9 is a technique increasingly used in efforts to correct the genetic (DNA) defects that cause a variety of diseases. A few years ago, University of California San Diego School of Medicine researchers redirected the technique to instead modify RNA in a method they call RNA-targeting Cas9 (RCas9).

Twist on CRISPR Gene Editing Treats Adult Onset Muscular Dystrophy in

Green muscle fibers with RCas9 (the therapeutic candidate for myotonic dystrophy) have eliminated their toxic RNA (red), whereas fibers lacking RCas9 (dark) have persisting toxic RNA (red). Credit: UC San Diego

In a new study published in Nature Biomedical Engineering, the team demonstrates that one dose of RCas9 gene therapy can chew up toxic RNA and almost completely reverse symptoms in a mouse model of myotonic dystrophy.

“Many other severe neuromuscular diseases, such as Huntington’s and ALS, are also caused by similar RNA buildup,” said senior author Gene Yeo, PhD, professor of cellular and molecular medicine at UC San Diego School of Medicine. “There are no cures for these diseases.” Yeo led the study with collaborators at Locanabio, Inc. and the University of Florida.

Normally, CRISPR-Cas9 works by directing an enzyme called Cas9 to cut a specific target gene (DNA), thereby allowing researchers to inactivate or replace the gene. RCas9 works similarly, but Cas9 is guided to an RNA molecule instead of DNA.

In a 2016 study, Yeo’s team demonstrated that RCas9 worked by using it to track RNA in live cells. In a 2017 study in lab models and patient-derived cells, the researchers used RCas9 to eliminate 95 percent of the aberrant RNA linked to myotonic dystrophy type 1 and type 2, one type of ALS and Huntington’s disease.

The current study advances RCas9 therapy further, reversing myotonic dystrophy type 1 in a living organism: a mouse model of the disease.

The approach is a type of gene therapy. The team packaged RCas9 in a non-infectious virus, which is needed to deliver the RNA-chewing enzyme inside cells. They gave the mice a single dose of the therapy or a mock treatment.

RCas9 reduced aberrant RNA repeats by more than 50 percent, varying a bit depending on the tissue, and the treated myotonic dystrophy mice became essentially indistinguishable from healthy mice.

Initially, the team was worried that the RCas9 proteins, which are derived from bacteria, might cause an immune reaction in the mice and be rapidly cleared away. So they tried suppressing the mice’s immune systems briefly during treatment. As a result, they were surprised and pleased to discover that they prevented immune reaction and clearance, leaving the viral vehicle and its RCas9 cargo to persist, and get the job done. What’s more, they did not see signs of muscle damage. In contrast, they saw an increase in the activity of genes involved in new muscle formation.

“This opens up the floodgates to start testing RNA-targeting CRISPR-Cas9 as a potential approach to treat other human genetic diseases — there are at least 20 caused by buildup of repetitive RNAs,” Yeo said.

It remains to be seen if RCas9-based therapies will work in humans, or if they might cause deleterious side effects, such as eliciting an undesired immune reaction. Preclinical studies such as this one will help the team work out potential toxicities and evaluate long-term exposure.

In 2017, Yeo co-founded a company called Locanabio to accelerate the development of RNA-targeting CRISPR-Cas9 through preclinical testing and into clinical trials for the treatment of myotonic dystrophy and potentially other diseases.

Source: UC San Diego




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Microsoft Buys Bethesda-Owner ZeniMax for $7.5 Billion

Microsoft said on Monday it would acquire ZeniMax Media for $7.5 billion (Rs. 55,223 crores) in cash, strengthening its Xbox video game offering with the studio behind titles such as Fallout and the Doom reboot.

ZeniMax is the parent company of Bethesda Softworks, which has also developed hits including The Elder Scrolls, Wolfenstein, and Dishonored.

The deal comes more than a week after Microsoft’s failed bid for short video app TikTok’s US assets. TikTok has currently structured the deal as a partnership with Oracle and Walmart rather than an outright sale.

Microsoft said it plans to bring Bethesda’s future games into its monthly Xbox Game Pass subscription service when they launch on Xbox or PC. The game pass now has more than 15 million subscribers, Microsoft added.

Bethesda’s structure and leadership will remain in place, Microsoft said.

Gaming is on a tear due to demand from stuck-at-home users during the COVID-19 pandemic and Microsoft has put its faith in offering users many ways to play via its cloud service and consoles at different price points.

Microsoft said the ZeniMax deal will close in the second half of fiscal year 2021, and have minimal impact on adjusted operating income in fiscal years 2021 and 2022.

© Thomson Reuters 2020

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Open source: Why governments need to go further

dc

Commentary: Yes, governments should open source their custom code. But more than that is needed.

Image: lucky-photographer, Getty Images/iStockphoto

For Drupal (and Acquia) founder Dries Buytaert, “the default [in government] should be ‘developed with public money, make it public code.'” That is, if a government is paying for software to be created, that software should be available under an open source license. While he acknowledged there might be exceptions (e.g., for military applications, as I’ve called out), his suggestion makes sense.

Years ago I argued that government mandates of open source made no sense. I still feel that way. Governments (and enterprises) should use whatever software best enables them to get work done. Increasingly, that software will be open source. But when good open source alternatives don’t yet exist, it makes no sense to mandate the use of suboptimal software. 

But software that governments create? There’s no compelling citizen-focused reason for closing it off. Instead, there are many reasons to open it up.

SEE: How to build a successful developer career (free PDF) (TechRepublic)

Of the people, by the people, for the people

This topic of why countries should embrace open source is an easy argument to make. As Buytaert pointed out, if public money pays for the code to be developed, why wouldn’t that code be available to the public (except, as mentioned, in the case of sensitive military software)? 

Some countries have already gone this route. As I detailed in 2016, Bulgaria is one of them. A few years later, Bulgaria has been preparing its own national source code repository, based on Git (as required by law: “administrative authorities shall use public storage and control systems for the source code and technical documentation for development, upgrading or deployment of information systems or electronic services”). 

This is a significant step toward greater transparency. However, it’s not enough.

SEE: Open source can thrive in a recession says Drupal creator Dries Buytaert (TechRepublic)

Collaborating on common government issues

As much as I understand Bulgaria’s desire to build its own source code repository, there’s even greater need for governments to collaborate on code beyond their borders. Think about it: Governments tend to do the same things, like collecting taxes, issuing parking tickets, etc. Currently, each government builds (or buys) software to tackle these tasks. Obscene quantities of custom code are created each year by government organizations operating in silos.

Why isn’t the city of Bogota sharing software with London, which shares software with Lagos, which shares software with Pocatello (that’s in Idaho, by the way)? 

As IBM president (and former Red Hat CEO) Jim Whitehurst said way back in 2009, “The waste in IT software development is extraordinary….Ultimately, for open source to provide value to all of our customers worldwide, we need to get our customers not only as users of open source products but truly engaged in open source and taking part in the development community.” This is particularly true in government, where there isn’t even the competitive pressure (e.g., Bogota doesn’t compete with Pocatello) that might prevent large financial institutions from collaborating (though even they partner on open source).

So, yes, we need governments to open source the software they pay to have built, to Buytaert’s point. But we also need those same governments to share that code beyond their borders, thereby driving greater innovation at lower cost for their citizens. 

Disclosure: I work for AWS but the views expressed herein are mine, not those of my employer.

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