Cholesterol Primer for Health Professionals

As research continues in the field of coronary artery disease, more information is revealed about various etiological factors. Emerging lipoprotein risk factors have been identified and are now starting to surface as instrumental in the cause and prevention of coronary artery disease. In order to conduct comprehensive cholesterol screening programs and counseling sessions a health professional must have a thorough understanding of lipid metabolism. Recent changes in cholesterol guidelines make it necessary to have a review that addresses the specifics of lipid management. A health professional needs an appropriate knowledge base to be able to understand a major coronary artery disease risk factor and thereby more effectively educate the public about lipid management and coronary artery disease risk reduction. Therefore, the purpose of this article is to review the role of cholesterol in both normal physiological functioning and disease causation and to examine the research concerning new emerging cholesterol risk factors

Thin silicon solar cells: Pathway to cost-effective and defect-tolerant cell design

Thinner silicon wafers are a pathway to lower cost without compromising the efficiency of solar cells. In this work, we study the recombination mechanism for thin and thick silicon heterojunction solar cells, and we discuss the potential of using more defective material to manufacture high performance thin solar cells. Modelling the performance of silicon heterojunction solar cells indicates that at open-circuit voltage the recombination is dominated by Auger and surface, representing nearly 90% of the total recombination. At maximum power point, the surface is responsible for 50 to 80% of the overall recombination, and its contribution increases inversely with the wafer thickness. The experimental results show that for lower quality CZ material with 1 ms bulk lifetime, 60 µm-thick cells perform better than 170 µm-thick cells. The potential efficiency gain is 1% absolute. The gains in voltage of using thinner wafers are significantly higher for the lower quality CZ material, 25 mV, than for standard CZ material, 10 mV

The use of diffuse reflectance infrared spectroscopy to monitor the oxidation of UV irradiated and naturally aged bitumen and asphalt

Between 2013 and 2014 it cost £4.2 billion to repair roads in England [Department for Transport, Statistical Release. (2014). Road conditions in England 2014. Retrieved from https://www.gov.uk/government/uploads/system/uploads/attachment]. Currently, road surface quality is monitored visually and repairs effected when visible damage arises. At this point, repair is unfeasible and costly and time-consuming resurfacing is required. Hence the ability to perform non-invasive monitoring and prediction of road surface degradation could provide a significant advance in highway maintenance. The oxidation of bitumen in road surfaces is known to promote failure of road surfaces as it reduces the cohesion between bitumen and aggregate. This paper reports the use of non-contact, diffuse reflectance infrared Fourier transfer (DRIFT) spectroscopy to monitor the oxidation process in bitumen and asphalt. We outline the comparison between natural and enhanced, artificially promoted ageing of bitumen and asphalt samples using UV light. The IR spectroscopic results show the evolution of oxidation product functional groups and allow the ageing of the samples to be monitored. After 4 weeks of UV ageing and a total exposure of 350 kW/m2 the area of the carbonyl feature had increased from 0.17 to 3.25 and the combined carboxylic & sulphoxide feature had increased from 0.93 to 8.97, while the C–H feature had decreased from 8.16 to 1.18, indicating an increase in the oxidation of the bitumen

Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire: an expert assessment

As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are unlikely in the near future, so to address this gap, we present estimates from 98 permafrost-region experts of the response of biomass, wildfire, and hydrologic carbon flux to climate change. Results suggest that contrary to model projections, total permafrost-region biomass could decrease due to water stress and disturbance, factors that are not adequately incorporated in current models. Assessments indicate that end-of-the-century organic carbon release from Arctic rivers and collapsing coastlines could increase by 75% while carbon loss via burning could increase four-fold. Experts identified water balance, shifts in vegetation community, and permafrost degradation as the key sources of uncertainty in predicting future system response. In combination with previous findings, results suggest the permafrost region will become a carbon source to the atmosphere by 2100 regardless of warming scenario but that 65%–85% of permafrost carbon release can still be avoided if human emissions are actively reduced

Factors affecting ammonium uptake in streams - an inter-biome perspective

The Lotic Intersite Nitrogen experiment (LINX) was a coordinated study of the relationships between North American biomes and factors governing ammonium uptake in streams. Our objective was to relate inter-biome variability of ammonium uptake to physical, chemical and biological processes. 2. Data were collected from 11 streams ranging from arctic to tropical and from desert to rainforest. Measurements at each site included physical, hydraulic and chemical characteristics, biological parameters, whole-stream metabolism and ammonium uptake. Ammonium uptake was measured by injection of \u275~-ammonium and downstream measurements of 15N-ammonium concentration. 3. We found no general, statistically significant relationships that explained the variability in ammonium uptake among sites. However, this approach does not account for the multiple mechanisms of ammonium uptake in streams. When we estimated biological demand for inorganic nitrogen based on our measurements of in-stream metabolism, we found good correspondence between calculated nitrogen demand and measured assimilative nitrogen uptake. 4. Nitrogen uptake varied little among sites, reflecting metabolic compensation in streams in a variety of distinctly different biomes (autotrophic production is high where allochthonous inputs are relatively low and vice versa). 5. Both autotrophic and heterotrophic metabolism require nitrogen and these biotic processes dominate inorganic nitrogen retention in streams. Factors that affect the relative balance of autotrophic and heterotrophic metabolism indirectly control inorganic nitrogen uptake

The effect of dietary phytochemicals on nuclear factor erythroid 2-related factor 2 (Nrf2) activation: a systematic review of human intervention trials

We conducted a systematic review of human trials examining the effects of dietary phytochemicals on Nrf2 activation. In accordance with the PRISMA guidelines, Medline, Embase and CAB abstracts were searched for articles from inception until March 2020. Studies in adult humans that measured Nrf2 activation (gene or protein expression changes) following ingestion of a phytochemical, either alone or in combination were included. The study was pre-registered on the Prospero database (Registration Number: CRD42020176121). Twenty-nine full-texts were retrieved and reviewed for analysis; of these, eighteen were included in the systematic review. Most of the included participants were healthy, obese or type 2 diabetics. Study quality was assessed using the Cochrane Collaboration Risk of Bias Assessment tool. Twelve different compounds were examined in the included studies: curcumin, resveratrol and sulforaphane were the most common (n = 3 each). Approximately half of the studies reported increases in Nrf2 activation (n = 10); however, many were of poor quality and had an unclear or high risk of bias. There is currently limited evidence that phytochemicals activate Nrf2 in humans. Well controlled human intervention trials are needed to corroborate the findings from in vitro and animal studies

Direct Transfer Patterning of Electrically Small Antennas onto Three‐Dimensionally Contoured Substrates

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90030/1/1166_ftp.pd

Message in a Bottle -- An Update to the Golden Record

Communication is an essential asset enabling humankind to forge an advanced civilization. Using approximately 31,000 languages from the Stone Age to our present digital information society, humans have connected and collaborated to accomplish remarkable feats. As the newly dawned Space Age progresses, we are attempting to communicate with intelligent species beyond our world, on distant planets and in Earth's far future. Absent mutually understood signs, symbols, and semiotic conventions, this study, the "Message in a Bottle", uses scientific methods to assess and design a means of communication encapsulating the story of humanity, conveying our thoughts, emotions, ingenuity, and aspirations. The message will be structured to provide a universal yet contextual understanding of modern human society, evolution of life on Earth, and challenges for the future. In assembling this space and time capsule, we aim to energize and unite current generations to celebrate and preserve humanity

Crystal structure and carbohydrate analysis of Nipah virus attachment glycoprotein:a template for antiviral and vaccine design

Two members of the paramyxovirus family, Nipah virus (NiV) and Hendra virus (HeV), are recent additions to a growing number of agents of emergent diseases which use bats as a natural host. Identification of ephrin-B2 and ephrin-B3 as cellular receptors for these viruses has enabled the development of immunotherapeutic reagents which prevent virus attachment and subsequent fusion. Here we present the structural analysis of the protein and carbohydrate components of the unbound viral attachment glycoprotein of NiV glycoprotein (NiV-G) at a 2.2-A resolution. Comparison with its ephrin-B2-bound form reveals that conformational changes within the envelope glycoprotein are required to achieve viral attachment. Structural differences are particularly pronounced in the 579-590 loop, a major component of the ephrin binding surface. In addition, the 236-245 loop is rather disordered in the unbound structure. We extend our structural characterization of NiV-G with mass spectrometric analysis of the carbohydrate moieties. We demonstrate that NiV-G is largely devoid of the oligomannose-type glycans that in viruses such as human immunodeficiency virus type 1 and Ebola virus influence viral tropism and the host immune response. Nevertheless, we find putative ligands for the endothelial cell lectin, LSECtin. Finally, by mapping structural conservation and glycosylation site positions from other members of the paramyxovirus family, we suggest the molecular surface involved in oligomerization. These results suggest possible pathways of virus-host interaction and strategies for the optimization of recombinant vaccines

Required Levels of Catalysis for Emergence of Autocatalytic Sets in Models of Chemical Reaction Systems

The formation of a self-sustaining autocatalytic chemical network is a necessary but not sufficient condition for the origin of life. The question of whether such a network could form “by chance” within a sufficiently complex suite of molecules and reactions is one that we have investigated for a simple chemical reaction model based on polymer ligation and cleavage. In this paper, we extend this work in several further directions. In particular, we investigate in more detail the levels of catalysis required for a self-sustaining autocatalytic network to form. We study the size of chemical networks within which we might expect to find such an autocatalytic subset, and we extend the theoretical and computational analyses to models in which catalysis requires template matching