gebhart/patrepeval huggingface dataset:
Solar-based Single-stage High-efficiency Grid-connected Inverter (2005)

Renewable energy source plays an important role in the energy cogeneration and distribution. Traditional solar-based inverter system is two stages in cascaded, which has a simpler controller but low efficiency. A new solar-based single-stage grid-connected inverter system can achieve higher efficiency by reducing the power semiconductor switching loss and output stable and synchronized sinusoid current into the utility grid. Controlled by the digital signal processor, the inverter can also draw maximum power from the solar array, thereby maximizing the utilization of the solar array. In Chapter 1, a comparison between the traditional two-stage inverter and the single-stage inverter is made. To increase the ability of power processing and enhance the efficiency further, a full-bridge topology is chosen, which applies the phase-shift technique to achieve zero-voltage transition. In Chapter 2, average-mode and switch-mode Pspice simulations are applied. All the features of the inverter system are verified, such as stability, zero voltage transition and feed-forward compensation, etc. All these simulation results provide useful design tips for prototyping. In Chapter 3, a phase-shift controller is designed based on UCC3895. Also, a detailed design procedure is given, including key components selection, transformer and inductor design and driver circuits design. In Chapter 4, experimental results of a prototype DC/DC converter are presented and analyzed. By optimization of the circuit, the problems of the prototype are solved and the prototype is working stably. The thesis' conclusion is given in Chapter 5.
Soluble expression of proteins correlates with a lack of positively-charged surface (2013)

Prediction of protein solubility is gaining importance with the growing use of protein molecules as therapeutics, and ongoing requirements for high level expression. We have investigated protein surface features that correlate with insolubility. Non-polar surface patches associate to some degree with insolubility, but this is far exceeded by the association with positively-charged patches. Negatively-charged patches do not separate insoluble/soluble subsets. The separation of soluble and insoluble subsets by positive charge clustering (area under the curve for a ROC plot is 0.85) has a striking parallel with the separation that delineates nucleic acid-binding proteins, although most of the insoluble dataset are not known to bind nucleic acid. Additionally, these basic patches are enriched for arginine, relative to lysine. The results are discussed in the context of expression systems and downstream processing, contributing to a view of protein solubility in which the molecular interactions of charged groups are far from equivalent.
The autocrine production of transforming growth factor-beta1 during lymphocyte activation. A study with a monoclonal antibody-based ELISA. (1990)

We describe the production and characterization of three mAb to transforming growth factor-beta (TGF-beta) and the use of two of them for the development of a TGF-beta 1-specific ELISA and for the study of the regulation of immune function in vitro. All three mAb bound recombinant human TGF-beta 1 (rHuTGF-beta 1) with high affinity and recognized the dimer form of this molecule in immunoblots. mAb 2G7 immunoprecipitated rHuTGF-beta 1, TGF-beta 2, and rHuTGF-beta 3 and neutralized the growth inhibitory activity of all three molecules in vitro on mink lung epithelial-like cells, Mv1Lu, indicating a shared neutralization epitope. mAb 4A11 neutralized and immunoprecipitated only rHuTGF-beta 1, and mAb 12H5 immunoprecipitated rHuTGF-beta 1 but had no effect on the bioactivity of either rHuTGF-beta 1, TGF-beta 2, or rHuTGF-beta 3. These results suggest that a second neutralization epitope may be unique to TGF-beta 1. The ELISA was developed with mAb 4A11 and 12H5, with a range of 0.63 to 40 ng/ml, i.e., a sensitivity of 0.63 ng/ml or 63 pg/sample. The assay is accurate, precise, and specific for the active but not the inactive or latent TGF-beta 1 complex and fails to react with TGF-beta 2, rHuTGF-beta 3, inhibin A, and activin A. Supernatants obtained from serum-free cultures of human PBMC from multiple donors contained significant quantities of TGF-beta 1 (3 to 15 ng/ml), which was detected in the ELISA only after pH 2 treatment to convert latent TGF-beta to the active form. Treatment of the PBMC with either recombinant human IL-2 (rHuIL-2) or PHA-P/PMA enhanced the production of latent TGF-beta 1. mAb 4A11 and 2G7, but not mAb 12H5 enhanced both the proliferative response of PBMC to rHuIL-2/rHuTNF-alpha and PHA-P and the development of the rHuIL-2/rHuTNF-alpha treated PBMC into LAK cells with cytotoxic activity against COLO target cells. These findings suggest that although PBMC secrete latent TGF-beta 1, mechanisms that convert the latent TGF-beta complex into an active form exist in vitro and that the endogenously produced TGF-beta can regulate immune functions in an autocrine fashion.
Tailoring the dielectric properties of HfO2–Ta2O5 nanolaminates (1996)

Dielectric thin films applicable, for instance, as insulating layers in electroluminescent display devices have been studied. In order to improve dielectric characteristics HfO2–Ta2O5 nanolaminates were prepared by atomic layer epitaxy at 325 °C. The nanolaminates were evaluated in capacitance and current–voltage measurements. By optimizing the layer thicknesses in the nanolaminate structures the dielectric properties, especially leakage current densities, could be tailored remarkably. The best nanolaminates showed charge storage factors improved up to 8 times when compared with those of the single oxide films. The presence of nanosize crystallites of monoclinic and metastable tetragonal HfO2 was observed by x-ray diffraction analysis.
Electron resonant tunneling in Si/SiGe double barrier diodes (1991)

We report upon the fabrication and characterization of the first n-type resonant tunneling diodes in the SiGe materials system. The devices fabricated were Si/SiGe/Si/SiGe/Si double-barrier diodes, employing strain-relieved SiGe as the barrier layers surrounding pseudomorphic tensile strained Si. These devices were prepared using ultrahigh vacuum chemical vapor deposition. Negative differential conductance is observed at room temperature in these devices with a peak-to-valley ratio of 1.2. The corresponding value at 77 K is 1.5.
Synthesis and characterization of DNA oligomers and duplexes containing covalently attached molecular labels: comparison of biotin, fluorescein, and pyrene labels by thermodynamic and optical spectroscopic measurements (1989)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and characterization of DNA oligomers and duplexes containing covalently attached molecular labels: comparison of biotin, fluorescein, and pyrene labels by thermodynamic and optical spectroscopic measurementsJoshua Telser, Kenneth A. Cruickshank, Larry E. Morrison, and Thomas L. NetzelCite this: J. Am. Chem. Soc. 1989, 111, 18, 6966–6976Publication Date (Print):August 1, 1989Publication History Published online1 May 2002Published inissue 1 August 1989https://pubs.acs.org/doi/10.1021/ja00200a011https://doi.org/10.1021/ja00200a011research-articleACS PublicationsRequest reuse permissionsArticle Views822Altmetric-Citations113LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Decreased Risk of Fractures of the Hip and Lower Forearm with Postmenopausal Use of Estrogen (1980)

We interviewed 327 women who had been 50 to 74 years of age when treated for fracture of the hip of lower forearm, to determine their use (or lack of use) of estrogen preparations. Their responses were compared with those in a random sample of 567 women who were of similar age and from the same region. The risk of fracture was 50 to 60 per cent lower in women who had used these drugs for six years or longer than in women who hadnot used them (95 per cent confidence interval of relative risk, 0.3 to 0.6); those using them for shorter periods received less benefit, if any. A decreased risk of fracture was clearly evident only in women still taking estrogens and evident at either common daily dose (0.625 and 1.25 mg). In conjunction with the finding that estrogens can retard the development of osteoporosis in postmenopausal women, our data argue that lowering of the risk of hip and forearm fractures must be weighed as a benefit of long-term estrogen use.
Erythropoietin crosses the blood–brain barrier to protect against experimental brain injury (2000)

Erythropoietin (EPO), recognized for its central role in erythropoiesis, also mediates neuroprotection when the recombinant form (r-Hu-EPO) is directly injected into ischemic rodent brain. We observed abundant expression of the EPO receptor at brain capillaries, which could provide a route for circulating EPO to enter the brain. In confirmation of this hypothesis, systemic administration of r-Hu-EPO before or up to 6 h after focal brain ischemia reduced injury by approximately 50-75%. R-Hu-EPO also ameliorates the extent of concussive brain injury, the immune damage in experimental autoimmune encephalomyelitis, and the toxicity of kainate. Given r-Hu-EPO's excellent safety profile, clinical trials evaluating systemically administered r-Hu-EPO as a general neuroprotective treatment are warranted.
Blue Electroluminescence of Substituted Polyacetylenes (1996)

We report blue emission from a series of alkyl and phenyl disubstituted polyacetylenes, i.e., poly(1-phenyl-1-alkynes) (PPhAs), with alkyne being n -propyne, n -butyne, and n -octyne. Blue electroluminescence from PPhAs is observed by employing a cell with an ITO (indium-tin oxide) coated glass substrate/PPhA/Mg/Al structure. The color of luminescence is changed from blue-green to pure blue and the luminescence intensity is enhanced when the length of alkyl side chain increases, while neither an alkyl nor a phenyl monosubstituted polyacetylene shows an intense luminescence. The electroluminescence efficiency of PPhAs is not efficiently improved by doping with a common electron-transporting material 2-(4-biphenylyl)-5-(4- t -butylphenyl)-1,3,4-oxadiazole (PBD).
Fe-C-N Oxygen Reduction Catalysts Prepared by Combinatorial Sputter Deposition (2006)

Thin-film libraries of libraries (; ) have been prepared by combinatorial sputter deposition. The libraries were subsequently annealed at 700, 800, and to induce structural and compositional changes. Respectable catalytic activity was achieved with libraries having and that were annealed at . This is explained in terms of nitrogen content and the degree of graphitization of the annealed catalysts.
4 Yeast Pre-mRNA Splicing (1992)

I. INTRODUCTION The study of pre-mRNA splicing in yeast has enjoyed remarkable success during the past several years (for other recent reviews, see Guthrie 1991; Rosbash and Seraphin 1991; Ruby and Abelson 1991). This is now a mature discipline in which detailed and mechanistic questions are being asked and answered. However, the complexity of the process, i.e., the large number of gene products needed for splicing and the multiple levels at which the problem is currently being studied, can limit the attention of the casual observer. Yet conclusions from these studies in yeast have played an important, if not central, role in our current view of how eukaryotic pre-mRNA processing takes place. As with many other topics covered in these volumes, two facts help to explain the importance of the yeast work on splicing. First, Saccharomyces cerevisiae allows the application of the three major tools of modern molecular biology: genetics, biochemistry, and physiology. This chapter will show that the ability to combine all three approaches has had a major influence on our current understanding of pre-mRNA splicing. Second, yeast splicing and metazoan splicing are very similar and rely on many of the same factors and principles. The apparent differences may reflect the shortcomings of the strictly biochemical approach available to the metazoan workers, rather than genuine differences in the processes. The genetic study of pre-mRNA splicing in S. cerevisiae has as its roots a study that preceded by almost 10 years the discovery of splicing itself. Between 1967 and 1970,...
Immune dysregulation in human immunodeficiency virus infection: know it, fix it, prevent it? (2008)

Infection of humans by the human immunodeficiency virus (HIV) causes a progressive, multifactorial impairment of the immune system eventually leading to the acquired immunodeficiency syndrome (AIDS). No cure or vaccine exists yet against HIV infection. More worrisome is the fact that despite having identified HIV as the cause of the AIDS, we still do not understand what pathogenic mechanisms lead to the debacle of the immune system. In this review we consider the extent and the limits of our knowledge of HIV pathogenesis, and how this knowledge may be used to design preventive and therapeutic approaches.
On the relations of intensity jnd’s to loudness and neural noise (1986)

It is shown experimentally that, in contradiction of the fundamental concept of Fechner's law, the intensity jnd for auditory sinusoidal signals follows loudness, rather than its derivative with respect to sound intensity. The evidence is obtained by comparing the jnd's of a population with normal hearing to those of a population with hearing loss accompanied by loudness recruitment. Although the recruitment increases the slope of the loudness function, the jnd's of both populations were found to be practically equal when the loudness were equal. The phenomenon is accounted for mathematically by assuming that psychophysically relevant neural noise depends not only on the magnitude of loudness, but also on its derivative with respect to sound intensity. A related derivation accounts for the near miss to Weber's law.
The epidemiology and natural history of Crohn’s disease in population‐based patient cohorts from North America: a systematic review (2002)

Between 400,000 and 600,000 patients in North America have Crohn's disease, and the natural history is marked by frequent exacerbations requiring treatment with corticosteroids, 5-aminosalicylate products and surgery.
An overview of epigenetics and chemoprevention (2010)

It is now appreciated that both genetic alteration, e.g. mutations, and aberrant epigenetic changes, e.g. DNA methylation, cause cancer. Epigenetic dysregulation is potentially reversible which makes it attractive as targets for cancer prevention. Synthetic drugs targeting enzymes, e.g. DNA methyltransferase and histone deacetylase, that regulate epigenetic patterns are active in clinical settings. In addition, dietary factors have been suggested to have potential to reverse aberrant epigenetic patterns. Uncovering the human epigenome can lead us to better understand the dynamics of DNA methylation in disease progression which can further assist in cancer prevention.
Nitrosylation precedes caspase‐3 activation and translocation of apoptosis‐inducing factor in neonatal rat cerebral hypoxia‐ischaemia (2004)

Excessive nitric oxide (NO) production after cerebral hypoxia-ischaemia (HI) may induce cellular injury in various ways, including reaction with superoxide to form the highly reactive peroxynitrite. We characterized the spatial and temporal formation of peroxynitrite through immunohistochemical detection of nitrosylated proteins. Nitrotyrosine immunoreactivity peaked around 3 h post-HI and was detected in areas of injury, as judged by the loss of microtubule-associated protein-2 (MAP-2) staining, in neurones, glia and endothelial cells. Nitrotyrosine staining co-localized with three other cellular markers of injury, active caspase-3, nuclear translocation of apoptosis-inducing factor (AIF) and an oligonucleotide hairpin probe detecting specific DNA strand breaks. The number of nitrotyrosine-positive cells at early time points outnumbered the cells positive for the other three markers of injury, indicating that nitrosylation preceded caspase-3 activation. Pharmacological inhibition of neuronal and inducible nitric oxide synthase (nNOS and iNOS) using 2-iminobiotin, which has been demonstrated earlier to be neuroprotective, significantly reduced nitrotyrosine formation and caspase-3 activation, but not nuclear translocation of AIF, in cortex and striatum of the ipsilatral hemisphere. In summary, nitrotyrosine is an early marker of cellular injury and inhibition of nNOS and iNOS is a promising strategy for neuroprotection after perinatal HI.
Long-Term Temporal Analysis of the Human Fecal Microbiota Revealed a Stable Core of Dominant Bacterial Species (2013)

Next-generation sequencing has greatly contributed to an improved ecological understanding of the human gut microbiota. Nevertheless, questions remain regarding the characteristics of this ecosystem and the ecological processes that shape it, and controversy has arisen regarding the stability of the bacterial populations and the existence of a temporal core. In this study, we have characterized the fecal microbial communities of three human individuals over a one-year period by 454 pyrosequencing of 16S rRNA tags in order to investigate the temporal characteristics of the bacterial communities. The findings revealed a temporal core of 33 to 40 species-level Operational Taxonomic Units (OTUs) within subjects. Although these OTUs accounted only for around 12% of the total OTUs detected, they added up to >75% of the total sequences obtained for each individual. In order to determine the capacity of the sequencing and bioinformatic approaches applied during this study to accurately determine the proportion of a core microbiota, we analyzed the fecal microbiota of nine mice with a defined three-member community. This experiment revealed that the sequencing approach inflated the amount of rare OTUs, which introduced a significant degree of artificial variation across samples, and hence reduced the apparent fraction of shared OTUs. However, when assessing the data quantitatively by focusing on dominant lineages, the sequencing approaches deliver an accurate representation of the community. In conclusion, this study revealed that the human fecal microbiota is dominated by around 40 species that maintain persistent populations over the duration of one year. The findings allow conclusions about the ecological factors that shape the community and support the concept of a homeostatic ecosystem controlled largely by deterministic processes. Our analysis of a three-member community revealed that methodological artifacts of OTU-based approaches complicate core calculations, and these limitations have to be considered in the interpretation of microbiome studies.
Metabolic behavior in rats of a nonprotein microemulsion resembling low‐density lipoprotein (1993)

A protein-free microemulsion (LDE) with a lipid composition resembling that of low-density lipoprotein (LDL) was used in metabolic studies in rats to compare LDE with the native lipoprotein. LDE labeled with radioactive lipids was injected into the bloodstream of male Wistar rats, and plasma kinetics of the labeled lipids were followed on plasma samples collected at regular intervals for 12 h after injection. The 24-h LDE uptake by different tissues was also measured in tissue samples excised after the animals had been sacrificed. We found that LDE plasma kinetics were similar to those described for native LDL [fractional clearance rate (FCR) of cholesteryl ester, 0.42 +/- 0.11 h-1]. The major site for LDE uptake was the liver, and the tissue distribution of the LDE injected radioactivity was as one would expect for LDL. To test whether LDE was taken up by the specific LDL receptors, the LDE emulsion was injected into rats treated with 17 alpha-ethinylestradiol, which is known to increase the activity of these receptors; as expected, removal of LDE from the bloodstream increased (FCR = 0.90 +/- 0.35 h-1). On the other hand, saturation of the receptors that remove remnants by prior infusion of massive amounts of lymph chylomicrons did not change LDE plasma kinetics. These results indicate that LDE is cleared from plasma by B,E receptors and not by the E receptors that remove remnants. Incorporation of free cholesterol into LDE increased LDE plasma clearance. Incubation studies also showed that LDE incorporates a variety of apolipoproteins, including apo E, a ligand for recognition of lipoproteins by specific receptors.(ABSTRACT TRUNCATED AT 250 WORDS)
Polymer–Monomer Pairs as a Reaction System for the Synthesis of Magnetic Fe3O4–Polymer Hybrid Hollow Nanospheres (2004)

Magnetic hollow Fe3O4–polymer hybrid nanospheres (see figure) were prepared by adding Fe3O4 nanoparticles to an aqueous solution of polymer–monomer pairs composed of a cationic polymer (chitosan) and an anionic monomer (acrylic acid), followed by polymerization of acrylic acid and selective crosslinking of chitosan at the end of the polymerization.
Sleep as a Window into the World of Fibromyalgia Syndrome (2011)

One of the most clinically problematic challenges in the management of fibromyalgia syndrome (FM) is the unrefreshing nature of sleep. The problem goes beyond misperceiving the duration or quality of sleep, to a point where patients may feel worse after sleep — a complete loss of the restorative power of sleep. This clinical feature has been associated with changes in sleep that are not readily determined by conventional sleep stages and scoring, but may be identified by a number of complementary analyses. In essence, they all capture in some form the dominance of low amplitude fluctuations in physiological signals during sleep1,2. “Low” is a relative term — pathological sleep, a good example of which is sleep apnea, is dominated by oscillations recurring in nearly every signal trace, every 25–35 seconds. There is a separate set of oscillations at a higher frequency that dominates slow-wave sleep and unfragmented N2 non-rapid eye movement (NREM) sleep, centered on respiration, best seen as strong sinus arrhythmia and breath-to-breath respiratory modulation of blood pressure during periods of stable breathing3. In the electroencephalographic (EEG) … Address correspondence to Dr. Thomas. E-mail: rthomas1{at}bidmc.harvard.edu