gebhart/patrepeval huggingface dataset:
A Simulation Study on the Transient Leakage Current Analysis of a GaN Epitaxial Layer (2020)

GaN epitaxial layers on Si substrate are being used as semiconductors for power devices owing to its wide bandgap, a high breakdown voltage with low on-resistance [1]. Due to the presence of crystal defect both in energy and its depth profile, a transient behavior is commonly observed in the channel current. Some of characterization methods, including deep level transient spectroscopy (DLTS), can extract the energy levels with its depth profile, by adopting a Schottky electrode to the epitaxial layer. Therefore, the extracted profile is limited to the surface of the GaN layers. In this work, we conducted a simulation study to extract the defect density profile from a direct current obtained from a GaN epitaxial layer on Si substrate with an Ohmic contact electrode to the surface. While applying a step voltage to the electrode, the transient current was measured and characterized. The proposed defect extraction method can be analytically expressed by the change in the depletion capacitance (Δ C ) in the epitaxial layer upon a voltage of V applied to the electrode at t =0 as shown in equation (1). Here, ε , W o d , W ∞ d , q , N d and N t are the permittivity, depletion width at t=0, depletion width at steady state, doping density of the GaN layer and the trap density, respectively. The change in the charge accumulated to the electrode (Δ Q ) can be written as the equation (2). Therefore, by the integral of the transient current, one can obtain the relationship between V and N t , which can be transformed into the defect density depth profile of the epitaxial layer. The simulated model is shown in fig. 1(a), where two GaN layers of each N d =10 16 /cm 3 are stacked with in two metal electrodes. The area of the electrode is 0.1 mm 2 . Defect levels of E3 and E7 with a density of N t,E3 and N t,E7 are introduced in the top and bottom GaN layers, respectively. By applying a positive V to the Ohmic top electrode, the depletion width increases from the Schottky bottom electrode, depending on the N d . By the presence of E3 and E7, a transient current with a time constant depending on the defect levels is obtained as is shown in fig. 2(b). By obtaining the relationship between the Δ Q and the V , as shown in fig. (2), firstly we can extract the N d of each layer from the change in the slope. The extract N d values showed a nice agreement to the values set in the simulations. Also, from the Δ Q itself, we can deduce the N t of each layer. In conclusions, we have made a simulation of the transient current response of a stacked GaN layers with different defect levels. From the transient current integral, we can extract the doping density and the defect density of each layer. References [1] B. J. Baliga, Semicon. Sci. Tech. , 28 , 074011 (2013). [2] D.V. Lang, Journal of Applied Physics. , 45 , 3023 (1974) Figure 1
SiC MESFET hybrid amplifier with 30-W output power at 10 GHz (2002)

We report here the demonstration of over 30 watts of output power at X band from a single 12-mm SiC transistor under pulsed-mode conditions. For small (250-/spl mu/m) devices, we also report record high power densities of 5.2 W/mm at 3.5 GHz and 4.5 W/mm at 10 GHz. The 12-mm MESFET's were tested in hybrid amplifiers, matched with chip capacitors and microstrip lines on 15-mil alumina. When operated at 9.7 GHz at a drain bias of 50 V and gate bias of -5.5 V, these hybrid amplifiers showed pulsed output power as high as 30.5 watts at 2-dB compression, with 7.6 dB linear gain. Furthermore, output power of greater than 27 W was obtained with devices from each of three wafers processed together, indicating the good wafer-to-wafer performance of the SiC power MESFET process.
Pathophysiological role of changing atrial size and pressure in modulation of atrial natriuretic factor during evolving experimental heart failure (1990)

The divergent time course of the changes in plasma atrial natriuretic factor concentration, pulmonary capillary wedge pressure, and left atrial dimension suggests that in this model, the release of atrial natriuretic factor becomes attenuated as severe heart failure develops.
Der „Osteoporosis Care Gap“ bei Altersfrakturpatienten kann durch osteologische Begleitung entlang des Behandlungspfads minimiert werden! (2019)

Zusammenfassung Einleitung Ein Fracture Liaison Service (FLS) gilt als geeignete Organisationsstruktur, um den „Osteoporosis Care Gap“ zu schließen. Material und Methodik In diese FLS-Evaluations-Studie wurden zwischen 01/2014 und 12/2015 insgesamt 1270 Patienten &gt; 65 Jahre eingeschlossen, die am Universitätsspital Basel wegen einer Fraktur nach Niederenergietrauma behandelt wurden. Im persönlichen Gespräch konnte das FLS Team die Osteoporoserisikofaktoren erheben und eine ggf. bereits durchgeführte Osteoporosediagnostik oder -therapie erfragen. Auf dieser Basis wurden das individuelle Frakturrisiko errechnet und der Bedarf an weiterer Osteoporosediagnostik oder -therapie festgelegt. Resultate Das grosse, heterogene Kollektiv von Patienten mit Altersfraktur konnte auf diese Art in kleinere Patientengruppen mit jeweils ähnlichen Abklärungsbedürfnissen aufgeteilt werden. Dabei wurden 21 % der Patienten als bereits ausreichend abgeklärt und behandelt erkannt. Bei weiteren 67 % der Patienten konnten Massnahmen zur sekundären Frakturprävention bedarfsgerecht eingeleitet werden. Schlussfolgerung Mit unserem FLS Modell konnte die Versorgungslücke auf 12 % der Patienten verringert werden.
An in vivo comparative study of sonic, desert and Indian hedgehog reveals that hedgehog pathway activity regulates epidermal stem cell homeostasis (2004)

Despite the well-characterised role of sonic hedgehog (Shh) in promoting interfollicular basal cell proliferation and hair follicle downgrowth, the role of hedgehog signalling during epidermal stem cell fate remains largely uncharacterised. In order to determine whether the three vertebrate hedgehog molecules play a role in regulating epidermal renewal we overexpressed sonic (Shh), desert (Dhh) and Indian (Ihh) hedgehog in the basal cells of mouse skin under the control of the human keratin 14 promoter. We observed no overt epidermal morphogenesis phenotype in response to Ihh overexpression, however Dhh overexpression resulted in a range of embryonic and adult skin manifestations indistinguishable from Shh overexpression. Two distinct novel phenotypes were observed amongst Shh and Dhh transgenics, one exhibiting epidermal progenitor cell hyperplasia with the other displaying a complete loss of epidermal tissue renewal indicating deregulation of stem cell activity. These data suggest that correct temporal regulation of hedgehog activity is a key factor in ensuring epidermal stem cell maintenance. In addition, we observed Shh and Dhh transgenic skin from both phenotypes developed lesions reminiscent of human basal cell carcinoma (BCC), indicating that BCCs can be generated despite the loss of much of the proliferative (basal) compartment. These data suggest the intriguing possibility that BCC can arise outside the stem cell population. Thus the elucidation of Shh (and Dhh) target gene activation in the skin will likely identify those genes responsible for increasing the proliferative potential of epidermal basal cells and the mechanisms involved in regulating epidermal stem cell fate.
Fluid‐Driven Soft CoboSkin for Safer Human–Robot Collaboration: Fabrication and Adaptation (2021)

Sensitive Robot Skin In article number 2000038, Geng Yang and co-workers present a fluid-driven soft robot skin with sensing and actuating function that is successfully applied to a collaborative robot. The two arms illustrated on the cover attempt to express the unintended human-robot collision and the contact force sensing process of the CoboSkin. The Tai Chi diagram is composed of an array of two key enabling components of the CoboSkin, including the sensitive cells for force sensing and actuating cells for stiffness control. The Tai Chi diagram represents the harmonious relationship not only between humans and robots during human-robot collaboration, but also between the sensitive function and controllable stiffness of the CoboSkin.
Voice to Vision II: End of Tumbalalaika (2004)

University of Minnesota Center for Holocaust and Genocide Studies. University of Minnesota Department of Art.
FEM-Simulation of the Human Lens during Accommodation (2005)

Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text P. Breitenfeld, T. Ripken, and H. Lubatschowski, "FEM-Simulation of the Human Lens during Accommodation," in Therapeutic Laser Applications and Laser-Tissue Interactions II, H. van den Bergh and A. Vogel, eds., Vol. 5863 of Proc. SPIE (Optica Publishing Group, 2005), paper SuB2. Export Citation BibTex Endnote (RIS) HTML Plain Text Citation alert Save article
Activity and Stability of Nanoscale Oxygen Reduction Catalysts (2015)

Design of highly active and stable nanoscale catalysts for electro-oxidation of small organic molecules is of great importance to the development of efficient fuel cells. The amount and instability of Pt-based catalysts in the cathode limits the cost, efficiency and lifetime of proton exchange membrane fuel cells. We developed a microscopic understanding of the factors governing activity and stability in Pt and PtM alloys. Experimental efforts were focused on probing the size and shape dependence of ORR activity of Pt-based nanoparticles supported on carbon nanotubes. A microscopic understanding of the activity was achieved by correlating voltammetry and rotating ring disk electrodes to surface atomic and electronic structures, which were elucidated predominantly by high-resolution transmission electron microscopy (HRTEM), Scanning transmission electron microscopy energy dispersive X-ray Spectroscopy (STEM-EDS) and synchrotron X-ray absorption spectroscopy (XAS).
<i>In vitro</i><sup>1</sup>H NMR “mapping” of human intervertebral discs (1986)

Human intervertebral discs were investigated by 1H NMR in vitro. The measured parameters of samples differently located in discs give the "maps" of discs. The spin-lattice relaxation-time maps show similar structure to dry matter and bound water maps, which might mean the future possibility to detect certain disc processes via accurate T1 images.
Conduction-band electron effective mass in Zn0.87Mn0.13Se measured by terahertz and far-infrared magnetooptic ellipsometry (2006)

We determine the electron effective mass parameter m*=0.086±0.004m0 of thin-film n-type low-chlorine-doped Zn0.87Mn0.13Se with free-charge-carrier concentration N=4.5×1017cm−3 and optical mobility μ=300±20cm2∕(Vs) using magneto-optic generalized ellipsometry in the terahertz and far-infrared spectral domain for wave numbers from ω=30–650cm−1. The room-temperature measurements were carried out with magnetic fields up to 3 T. We employ synchrotron and black-body radiation sources for the terahertz and far-infrared spectral regions, respectively. Comparison with previous experimental results from samples with considerably higher free electron density and theoretical calculations suggest that our value is sufficiently unaffected by band nonparabolicity and provides a good approximation of the Γ-point conduction band mass in Zn0.87Mn0.13Se. We further provide optical phonon mode parameters and the high-frequency dielectric constant.
Factors Associated with High Myopia After 7 Years of Follow-up in the Correction of Myopia Evaluation Trial (COMET) Cohort (2007)

Children who developed high myopia during 7 years of follow-up were younger and had more myopia at baseline. They also were more likely to have two myopic parents. These children may be at greater risk for sight-threatening conditions later in life.
Theoretical model calculations of long-haul edge-emitting communication lasers: comparison of fractally mixed, fine-pitched and continuously chirped DFB gratings (2004)

We have studied index-coupled semiconductor distributed feedback (DFB) lasers and compared three types including continuously chirped gratings, fractally mixed gratings and fine-pitched gratings. Using transfer matrix model calculations self-consistently combined with the set of rate equations, important static and dynamic laser properties are compared and it is found that they can be designed to be nearly identical above laser threshold for the three types of lasers. Therefore, the grating configuration involving the lowest effort and production cost can be selected: continuously chirped DFB lasers implemented by bent waveguides. These gratings are very attractive since they show high performance and have the potential of production at lower cost.
Pneumoproteinaemia: a new perspective in the assessment of lung disorders (1998)

Here we make the hypothesis that the determination of the concentration of lung specific secretory proteins in serum or pneumoproteinaemia could be used in the evaluation of lung disorders with a similar utility as proteinuria in kidney diseases involving the glomeruli. Human and experimental data indicate that comparable structural and functional features govern the passage of proteins across the lung epithelium/blood barrier and the glomerular filter. The concentrations in serum of some lung-specific secretory proteins, such as the bronchiolar Clara cell 16 kDa protein (CC16) and alveolar surfactant-associated proteins A and B (SP-A and SP-B, respectively), might be used to assess the integrity of the bronchoalveolar/blood barrier known to be disrupted in many lung disorders. In addition, if this barrier is intact or slightly compromised, these proteins might serve as peripheral markers to detect changes in secretory epithelial cells in the lung.
Desynchronization of slow oscillations in the basal ganglia during natural sleep (2018)

Slow oscillations of neuronal activity alternating between firing and silence are a hallmark of slow-wave sleep (SWS). These oscillations reflect the default activity present in all mammalian species, and are ubiquitous to anesthesia, brain slice preparations, and neuronal cultures. In all these cases, neuronal firing is highly synchronous within local circuits, suggesting that oscillation-synchronization coupling may be a governing principle of sleep physiology regardless of anatomical connectivity. To investigate whether this principle applies to overall brain organization, we recorded the activity of individual neurons from basal ganglia (BG) structures and the thalamocortical (TC) network over 70 full nights of natural sleep in two vervet monkeys. During SWS, BG neurons manifested slow oscillations (∼0.5 Hz) in firing rate that were as prominent as in the TC network. However, in sharp contrast to any neural substrate explored thus far, the slow oscillations in all BG structures were completely desynchronized between individual neurons. Furthermore, whereas in the TC network single-cell spiking was locked to slow oscillations in the local field potential (LFP), the BG LFP exhibited only weak slow oscillatory activity and failed to entrain nearby cells. We thus show that synchrony is not inherent to slow oscillations, and propose that the BG desynchronization of slow oscillations could stem from its unique anatomy and functional connectivity. Finally, we posit that BG slow-oscillation desynchronization may further the reemergence of slow-oscillation traveling waves from multiple independent origins in the frontal cortex, thus significantly contributing to normal SWS.
Stereoselective Synthesis of (1→6)‐α‐Linked Di‐ and Trisaccharides, Derivatives of 2‐Deoxysugars. (2006)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access the actual ChemInform Abstract, please click on HTML or PDF.
Generation of half-integer harmonics and efficient THz-to-visible frequency conversion in strained graphene (2021)

We study the generation of harmonics from graphene under the influence of an artificial magnetic field, generated via bending of a graphene flake. We show how the Landau level structure induced by the pseudomagnetic field breaks the centrosymmetry of graphene, thus allowing the generation of even harmonics. We also show that depending on the impinging pulse duration, the nonlinear signal does not only contain the integer harmonics of the impinging pulse but also its half-integer ones due to the peculiar square-root-like nature of Landau levels in graphene.
Real-time genomic profiling of histiocytoses identifies early-kinase domain BRAF alterations while improving treatment outcomes (2017)

Many patients with histiocytic disorders such as Langerhans cell histiocytosis (LCH) or Erdheim-Chester disease (ECD) have treatment-refractory disease or suffer recurrences. Recent findings of gene mutations in histiocytoses have generated options for targeted therapies. We sought to determine the utility of prospective sequencing of select genes to further characterize mutations and identify targeted therapies for patients with histiocytoses. Biopsies of 72 patients with a variety of histiocytoses underwent comprehensive genomic profiling with targeted DNA and RNA sequencing. Fifteen patients (21%) carried the known <i>BRAF</i> V600E mutation, and 11 patients (15%) carried various mutations in <i>MAP2K1</i>, which we confirm induce constitutive activation of extracellular signal-regulated kinase (ERK) and were sensitive to inhibitors of mitogen-activated protein kinase kinase (MEK, the product of <i>MAP2K1</i>). We also identified recurring <i>ALK</i> rearrangements, and 4 LCH patients with an uncommon in-frame deletion in <i>BRAF</i> (N486_P490del or N486_T491>K), resulting in constitutive activation of ERK with resistance to V600E-specific inhibitors. We subsequently describe clinical cases where patients with aggressive multisystem LCH experience dramatic and sustained responses to monotherapy with either dabrafenib or trametinib. These findings support our conclusion that comprehensive genomic profiling should be regularly applied to these disorders at diagnosis, and can positively impact clinical care.
Cell-mediated and cell membrane-coated nanoparticles for drug delivery and cancer therapy (2020)

Nanotechnology-based drug delivery platforms have been developed over the last two decades because of their favorable features in terms of improved drug bioavailability and stability. Despite recent advancement in nanotechnology platforms, this approach still falls short to meet the complexity of biological systems and diseases, such as avoiding systemic side effects, manipulating biological interactions and overcoming drug resistance, which hinders the therapeutic outcomes of the NP-based drug delivery systems. To address these issues, various strategies have been developed including the use of engineered cells and/or cell membrane-coated nanocarriers. Cell membrane receptor profiles and characteristics are vital in performing therapeutic functions, targeting, and homing of either engineered cells or cell membrane-coated nanocarriers to the sites of interest. In this context, we comprehensively discuss various cell- and cell membrane-based drug delivery approaches towards cancer therapy, the therapeutic potential of these strategies, and the limitations associated with engineered cells as drug carriers and cell membrane-associated drug nanocarriers. Finally, we review various cell types and cell membrane receptors for their potential in targeting, immunomodulation and overcoming drug resistance in cancer.
Source imaging of seizure onset predicts surgical outcome in pediatric epilepsy (2021)

Such an application may increase the number of children who are referred for epilepsy surgery and improve their outcome.
The Influence of Induction Therapy for Kidney Transplantation after a Non-Renal Transplant (2011)

Use of IT for kidney transplantation among prior non-renal transplant recipients may not offer a survival advantage in KALu or KAH. However, due to limited power, these findings should be interpreted cautiously. IT+ was associated with inferior outcomes for KALi. Use of IT should be judicially reconsidered in this complex group of recipients.
Molecular Mechanisms of Autophagy in the Cardiovascular System (2015)

Autophagy is a catabolic recycling pathway triggered by various intra- or extracellular stimuli that is conserved from yeast to mammals. During autophagy, diverse cytosolic constituents are enveloped by double-membrane vesicles, autophagosomes, which later fuse with lysosomes or the vacuole to degrade their cargo. Dysregulation in autophagy is associated with a diverse range of pathologies including cardiovascular disease, the leading cause of death in the world. As such, there is great interest in identifying novel mechanisms that govern the cardiovascular response to disease-related stress. First described in failing hearts, autophagy within the cardiovascular system has been characterized widely in cardiomyocytes, cardiac fibroblasts, endothelial cells, and vascular smooth muscle cells. In all cases, a window of optimal autophagic activity seems to be critical to the maintenance of cardiovascular homeostasis and function; excessive or insufficient levels of autophagic flux can each contribute to heart disease pathogenesis. Here, we review the molecular mechanisms that govern autophagosome formation and analyze the link between autophagy and cardiovascular disease.
Purification of the 56-kDa component of the bacteriophage T7 primase/helicase and characterization of its nucleoside 5′-triphosphatase activity. (1988)

Bacteriophage T7 gene 4 protein, purified from phage-infected cells, consists of a mixture of a 56- and a 63-kDa species that provides primase and helicase activities for T7 DNA replication. The 56-kDa species has been purified 1800-fold from Escherichia coli cells containing a plasmid that encodes this gene 4 protein. The purified 56-kDa protein is homogeneous, as determined by denaturing gel electrophoresis, and is monomeric in its native form, as indicated by gel filtration. The binding of the 56-kDa protein to single-stranded DNA is stimulated by nucleoside 5'-triphosphates, as is the case for a mixture of the two molecular weight species. In the presence of DNA, the 56-kDa protein preferentially hydrolyzes dTTP (Bernstein, J. A., and Richardson, C. C. (1988) Proc. Natl. Acad. Sci. U. S. A. 85, 396-400). Since nucleoside 5'-triphosphatase activity is necessary for both helicase activity and for translocation of gene 4 protein to primase recognition sites, we have characterized this activity using the 56-kDa protein alone. In the DNA-dependent hydrolysis reaction, the enzyme displays a Km of 10 mM for dTTP, and a Vmax of 2.9 x 10(-5) M/min/mg of protein (at 2.5 micrograms/ml). There is little cooperativity with respect to dTTP binding (Hill coefficient = 1.1) except in the presence of ribonucleoside 5'-triphosphate, an inhibitor of dTTP hydrolysis (Hill coefficient greater than 1.5). The apparent KD for single-stranded circular DNA is 0.2 microM. The active species in dTTP hydrolysis is an oligomer of at least two subunits, as indicated by the effect of enzyme concentration upon the rate of DNA-dependent hydrolysis. The 56-kDa protein also catalyzes DNA-independent hydrolysis of dTTP with a Km of 0.11 mM and a Vmax of 1.3 x 10(-7) M/min/mg of protein (at 8 micrograms/ml). The active species in DNA-independent dTTP hydrolysis is also an oligomer.
Free radicals in retinal and choroidal blood flow autoregulation in the piglet: interaction with prostaglandins. (1994)

These findings indicate that free radicals play a major role in setting the upper limit of RBF and ChBF autoregulation of the newborn animal. In addition, there exists a positive feedback interaction between free radicals and cyclooxygenase activity in ocular tissues, such that during hypertension the cyclooxygenase pathway is an important producer of free radicals and in turn is also activated by them.