Liquid sunshine Service, Robert F
Science (American Association for the Advancement of Science),
07/2018, Letnik:
361, Številka:
6398
Journal Article
Recenzirano
Ammonia made from sun, air, and water could turn Australia into a renewable energy superpower.
Renewable energy sources, such as wind and solar electricity, are the fastest growing energy sources in ...the world. But the sunniest and windiest spots on Earth are often far from cities where the power is needed, and there are few effective ways to ship electricity over long distances. That leaves much of the world's renewable energy potential untapped. Now, researchers are looking to use renewable electricity to make ammonia, which is already produced on an industrial scale as the main ingredient in fertilizer, and shipped worldwide. Today, ammonia is made primarily by stripping hydrogen molecules from natural gas and combining them with nitrogen purified from air, a process that generates about 1% of all humanmade carbon dioxide. In the future, ammonia could be produced by combining that nitrogen with hydrogen generated by splitting water. Devices called reverse fuel cells could also make it directly by using electricity and catalysts to split water and combine the hydrogen with nitrogen. These advances could enable ammonia to be produced economically on a small scale, allowing farmers to make their own fertilizer and renewable energy producers to store any excess power they may have and ship it where it's needed.
Catalytic approach could eliminate CO
2
emissions from the key step in making fertilizer.
Nitrogen is essential for all life. But even though nitrogen makes up 78% of the atmosphere, it's in a form ...that can't be used by living organisms. Instead it's tied up in nitrogen molecules made up of two nitrogen atoms that share a strong triple bond that's not easily broken. A century ago, two German chemists, Fritz Haber and Carl Bosch, figured out how to sever those bonds with high pressures and temperatures and weld nitrogen atoms with hydrogens to make ammonia, thereby converting nitrogen into the starting material for a nitrogen-rich fertilizer that can be taken up and used by microbes, plants, and people. That process has been so successful that ammonia-based fertilizers now enable farmers to feed billions more people than our planet could otherwise support. But ammonia production also comes at a high environmental cost, as it is responsible for 2% of worldwide energy use and thus a massive greenhouse gas footprint. However, on page
637
of this issue, U.S. chemists report that they've come up with a way to synthesize ammonia from air, water, and sunlight. If the approach can be scaled up, it could offer a means for making an essential commodity without a major cost to the climate.
This Perspective proposes definitions for key terms in the field of HIV-1 latency and eradication. In the context of eradication, a reservoir is a cell type that allows persistence of ...replication-competent HIV-1 on a timescale of years in patients on optimal antiretroviral therapy. Reservoirs act as a barrier to eradication in the patient population in which cure attempts will likely be made. Halting viral replication is essential to eradication, and definitions and criteria for assessing whether this goal has been achieved are proposed. The cell types that may serve as reservoirs for HIV-1 are discussed. Currently, only latently infected resting CD4+ T cells fit the proposed definition of a reservoir, and more evidence is necessary to demonstrate that other cell types, including hematopoietic stem cells and macrophages, fit this definition. Further research is urgently required on potential reservoirs in the gut-associated lymphoid tissue and the central nervous system.
We introduce SRISK to measure the systemic risk contribution of a financial firm. SRISK measures the capital shortfall of a firm conditional on a severe market decline, and is a function of its size, ...leverage and risk. We use the measure to study top financial institutions in the recent financial crisis. SRISK delivers useful rankings of systemic institutions at various stages of the crisis and identifies Fannie Mae, Freddie Mac, Morgan Stanley, Bear Stearns, and Lehman Brothers as top contributors as early as 2005-Q1. Moreover, aggregate SRISK provides early warning signals of distress in indicators of real activity.
For decades, combined estrogen-progestin oral contraceptive pills (OCPs) have been the first-line treatment for menstrual and pelvic pain associated with endometriosis without any clinical evidence ...of efficacy. Initial relief provided by OCPs is likely a result of improvement in primary dysmenorrhea. Biologic data and limited clinical evidence support a potential adverse effect of long-term use of OCPs on the progression of endometriosis. In contrast, there is randomized, controlled trial data to support the use of oral progestin-only treatment for pelvic pain associated with endometriosis and for suppressing the anatomic extent of endometriotic lesions. Both norethindrone acetate and dienogest have regulatory approval for treating endometriosis and may be better than OCPs as a first-line therapy.
The microbiome exerts essential functions in health and disease, modulating key processes in metabolism, inflammation and immunity. Recent evidence has revealed a key role of the microbiome in ...carcinogenesis as well as anti-cancer immune responses in mouse models and patients. Herein, we will review functions of the gut microbiome in hepatocellular carcinoma (HCC), the third leading cause of worldwide cancer mortality. The majority of HCC develops in patients with chronic liver disease, caused by viral hepatitis, non-alcoholic fatty liver disease (NAFLD) and alcohol-related fatty liver disease. In this review, we will discuss mechanisms by which the gut-liver axis promotes the development of HCC in mouse models and patients, including dysbiosis, the leaky gut and bacterial metabolites, with a particular focus on NAFLD as the fastest growing cause of HCC development. Moreover, we will review recent progress in harnessing the gut microbiome as a potential diagnostic tool and novel therapeutic target in patients with HCC, in particular in the setting of immunotherapy.
Cell line drug screening datasets can be utilized for a range of different drug discovery applications from drug biomarker discovery to building translational models of drug response. Previously, we ...described three separate methodologies to (1) correct for general levels of drug sensitivity to enable drug-specific biomarker discovery, (2) predict clinical drug response in patients and (3) associate these predictions with clinical features to perform in vivo drug biomarker discovery. Here, we unite and update these methodologies into one R package (oncoPredict) to facilitate the development and adoption of these tools. This new OncoPredict R package can be applied to various in vitro and in vivo contexts for drug and biomarker discovery.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
8.
Service Innovation Lusch, Robert F.; Nambisan, Satish
MIS quarterly,
03/2015, Letnik:
39, Številka:
1
Journal Article
Recenzirano
In this article, we offer a broadened view of service innovation—one grounded in service-dominant logic—that transcends the tangible–intangible and producer–consumer divides that have plagued extant ...research in this area. Such a broadened conceptualization of service innovation emphasizes (1) innovation as a collaborative process occurring in an actor-to-actor (A2A) network, (2) service as the application of specialized competences for the benefit of another actor or the self and as the basis of all exchange, (3) the generativity unleashed by increasing resource liquefaction and resource density, and (4) resource integration as the fundamental way to innovate. Building on these core themes, we offer a tripartite framework of service innovation: (1) service ecosystems, as emergent A2A structures actors create and recreate through their effectual actions and which offer an organizing logic for the actors to exchange service and cocreate value; (2) service platforms, which enhance the efficiency and effectiveness of service exchange by liquefying resources and increasing resource density (facilitating easy access to appropriate resource bundles) and thereby serve as the venue for innovation; and (3) value cocreation, which views value as cocreated by the service offer(er) and the service beneficiary (e.g., customer) through resource integration and indicate the need for mechanisms to support the underlying roles and processes. In discussing these components, we consider the role of information technology—both as an operand resource and as an operant resource—and then examine the implications for research and practice in digitally enabled service innovation.
Cell death represents a basic biological paradigm that governs outcomes and long-term sequelae in almost every hepatic disease condition. Acute liver failure is characterized by massive loss of ...parenchymal cells but is usually followed by restitution ad integrum. By contrast, cell death in chronic liver diseases often occurs at a lesser extent but leads to long-term alterations in organ architecture and function, contributing to chronic hepatocyte turnover, the recruitment of immune cells and activation of hepatic stellate cells. These chronic cell death responses contribute to the development of liver fibrosis, cirrhosis and cancer. It has become evident that, besides apoptosis, necroptosis is a highly relevant form of programmed cell death in the liver. Differential activation of specific forms of programmed cell death might not only affect outcomes in liver diseases but also offer novel opportunities for therapeutic intervention. Here, we summarize the underlying molecular mechanisms and open questions about disease-specific activation and roles of programmed cell death forms, their contribution to response signatures and their detection. We focus on the role of apoptosis and necroptosis in acute liver injury, nonalcoholic fatty liver disease (NAFLD), nonalcoholic steatohepatitis (NASH) and liver cancer, and possible translations into clinical applications.
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