gebhart/patrepeval huggingface dataset:
Spatial inhomogeneities in Al<sub><i>x</i></sub>Ga<sub>1−<i>x</i></sub>N quantum wells induced by the surface morphology of AlN/sapphire templates (2015)

The effects of the template on the optical and structural properties of Al0.75Ga0.25N/Al0.8Ga0.2N multiple quantum well (MQWs) laser active regions have been investigated. The laser structures for optical pumping were grown on planar c-plane AlN/sapphire as well as on thick epitaxially laterally overgrown (ELO) AlN layers on patterned AlN/sapphire. Two ELO AlN/sapphire templates were investigated, one with a miscut of the sapphire surface to the m-direction with an angle of 0.25°, the other with a miscut angle of 0.25° to the sapphire a-direction. The MQWs are studied by atomic force microscopy, plan-view cathodoluminescence (CL) at room temperature and 83 K as well as transmission electron microscopy using high-angle annular dark-field imaging and energy-dispersive x-ray spectroscopy. The results are compared to optical pumping measurements. It was found that the surface morphology of the templates determines the lateral wavelength distribution in the MQWs observed by spectral CL mappings. The lateral wavelength spread is largest for the laser structures grown on ELO AlN with miscut to sapphire a-direction caused by the local variation of the MQW thicknesses and the Ga incorporation at macrosteps on the ELO-AlN. A CL peak wavelength spread of up to 7 nm has been found. The MQWs grown on planar AlN/sapphire templates show a homogeneous wavelength distribution. However, due to the high threading dislocation density and the resulting strong nonradiative recombination, laser operation could not be achieved. The laser structures grown on ELO AlN/sapphire show optically pumped lasing with a record short wavelength of 237 nm.
Palladium Alkoxides:  Potential Intermediacy in Catalytic Amination, Reductive Elimination of Ethers, and Catalytic Etheration. Comments on Alcohol Elimination from Ir(III) (1996)

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTPalladium Alkoxides: Potential Intermediacy in Catalytic Amination, Reductive Elimination of Ethers, and Catalytic Etheration. Comments on Alcohol Elimination from Ir(III)Grace Mann and John F. HartwigView Author Information Department of Chemistry Yale University, P.O. Box 208107 New Haven, Connecticut 06520-8107 Cite this: J. Am. Chem. Soc. 1996, 118, 51, 13109–13110Publication Date (Web):December 25, 1996Publication History Received17 September 1996Published online25 December 1996Published inissue 1 January 1996https://doi.org/10.1021/ja963273wCopyright © 1996 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views5048Altmetric-Citations290LEARN 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 InReddit Read OnlinePDF (129 KB) Get e-AlertscloseSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Amines,Aromatic compounds,Ethers,Palladium,Reductive elimination Get e-Alerts
Wetting Kinetics and Microstructure Analysis of BNi2 Filler Metal over Selective Laser Melted Ti-6Al-4V Substrate (2020)

The wetting kinetics of nickel-based filler metal (BNi2) over selective laser-melted Ti-6Al-4V (SLMed TC4) titanium alloy in a protective argon atmosphere is experimentally investigated using a real-time in situ hot stage equipped with an optical microscope. The spreading processes at different temperatures are similar, and the overall wetting/spreading process can be roughly divided into three stages: (i) an initial stage, (ii) a rapid spreading stage, and (iii) an asymptotic stage. Moreover, the wetting kinetics of the BNi2/SLMed TC4 system can be expressed by empirical power exponential function <i>R<sup>n</sup>~t</i> with <i>n</i> = ~1. In the process of spreading, Ti-based solid solution (Ti(ss)) and intermetallic compound (Ti<sub>2</sub>Ni and TiB<sub>2</sub>) were formed at the interface within the reaction domain, and the phase transition of α' martensitic to α-Ti and β-Ti also took place. The influence of elevated temperature on the spreading and wetting kinetics of the BNi2/SLMed TC4 system was studied, and the results show that the increase of temperature has a slightly promoting effect on the spreading, but a limited impact on the value of <i>n</i>. In addition, the spreading and wetting kinetics of BNi2/SLMed TC4 system are similar to those of BNi2 on conventional forged TC4 substrate.
Macromolecular Imaging Agents Containing Lanthanides: Can Conceptual Promise Lead to Clinical Potential? (2012)

Macromolecular magnetic resonance imaging (MRI) contrast agents are increasingly being used to improve the resolution of this noninvasive diagnostic technique. All clinically-approved T<sub>1</sub> contrast agents are small molecule chelates of gadolinium [Gd(III)] that affect bound water proton relaxivity. Both the small size and monomeric nature of these agents ultimately limits the image resolution enhancement that can be achieved for both contrast enhancement and pharmacokinetic/biodistribution reasons. The multimeric nature of macromolecules, such as polymers, dendrimers, and noncovalent complexes of small molecule agents with proteins, have been shown to significantly increase the image contrast and resolution due to their large size and ability to incorporate multiple Gd(III) chlelation sites. Also, macromolecular agents are advantageous as they have the ability to be designed to be nontoxic, hydrophilic, easily purified, aggregation-resistant, and have controllable three-dimensional macromolecular structure housing the multiple lanthanide chelation sites. For these reasons, large molecule diagnostics have the ability to significantly increase the relaxivity of water protons within the targeted tissues and thus the image resolution for many diagnostic applications. The FDA approval of a contrast agent that consists of a reversible, non-covalent coupling of a small Gd(III) chelate with serum albumin for blood pool imaging (marketed under the trade names of Vasovist and Ablivar) proved to be one of the first diagnostic agent to capitalize on these benefits from macromolecular association in humans. However, much research and development is necessary to optimize the safety of these unique agents for in vivo use and potential clinical development. To this end, recent work in the field of polymer, dendrimer, and noncovalent complex-based imaging agents are reviewed herein and the future outlook of this field is discussed.
Behavior of Rapidly Expansion Materials for Maintenance Railroad Bed Subjected to Cyclic Loading (2009)

The differential settlement may be generated by the variation of stresses caused by the soft ground or ground water. The cracks are usually created when the structures are leaned or deformed due to the differential settlement. A grouting method has been mainly used till now to improve the bearing capacity of the ground when the foundation of the structure is deformed by differential settlements. However, when this method is used, it takes too long time to obtain the required strength and the period of the reinforcement effect is not long enough. The advantage of GPCON injection method is to have good mechanical properties and durability, and easy construction. In addition, the GPCON method rapidly fills up the void in soils by injecting some materials into underground and also obtain the increase of bearing and shearing forces due to the expansion. In this paper the restoration capability of the foundation settlement of railway and subway subjected to cyclic loading is analytically and experimentally evaluated using the high density rapidly expansion GPCON in order to investigate the types of deformations and vibrational characteristics.
A novel conditional <i>Sgsh</i> knockout mouse model recapitulates phenotypic and neuropathic deficits of Sanfilippo syndrome (2017)

Mucopolysaccharidosis (MPS) type IIIA, or Sanfilippo syndrome, is a neurodegenerative lysosomal storage disorder caused by a deficiency of the lysosomal enzyme N-sulfoglucosamine sulfohydrolase (SGSH), involved in the catabolism of heparan sulfate. The clinical spectrum is broad and the age of symptom onset and the degree of preservation of cognitive and motor functions appears greatly influenced by genotype. To explore this further, we generated a conditional knockout (Sgsh <sup>KO</sup> ) mouse model with ubiquitous Sgsh deletion, and compared the clinical and pathological phenotype with that of the spontaneous Sgsh <sup>D31N</sup> MPS-IIIA mouse model. Phenotypic deficits were noted in Sgsh <sup>KO</sup> mice prior to Sgsh <sup>D31N</sup> mice, however these outcomes did not correlate with any shift in the time of appearance nor rate of accumulation of primary (heparan sulfate) or secondary substrates (GM2/GM3 gangliosides). Other disease lesions (elevations in lysosomal integral membrane protein-II expression, reactive astrocytosis and appearance of ubiquitin-positive inclusions) were also comparable between affected mouse strains. This suggests that gross substrate storage and these neuropathological markers are neither primary determinants, nor good biomarkers/indicators of symptom generation, confirming similar observations made recently in MPS-IIIA patients. The Sgsh <sup>KO</sup> mouse will be a useful tool for elucidation of the neurological basis of disease and assessment of the clinical efficacy of new treatments for Sanfilippo syndrome.
Practical Total Syntheses of (R)-(+)- and (S)-(-)-14-Hydroxy-4,14-retro-retinol. (1994)

Practical and facile total syntheses of the remarkably unstable (R)-(+)-14-hydroxy-4, 14-retro-retinol [(R)-14HRR] 1 and of its enantiomer 2 have been achieved via an acid-catalyzed dehydration reaction of the respective tetraeneol intermediates 10 and its enantiomer obtained from (R)-(+)-1, 2-O-isopropylidene-butane-1, 2, 3-triol 3.
Machine Learning-Driven Multiscale Modeling: Bridging the Scales with a Next-Generation Simulation Infrastructure (2023)

Interdependence across time and length scales is common in biology, where atomic interactions can impact larger-scale phenomenon. Such dependence is especially true for a well-known cancer signaling pathway, where the membrane-bound RAS protein binds an effector protein called RAF. To capture the driving forces that bring RAS and RAF (represented as two domains, RBD and CRD) together on the plasma membrane, simulations with the ability to calculate atomic detail while having long time and large length- scales are needed. The Multiscale Machine-Learned Modeling Infrastructure (MuMMI) is able to resolve RAS/RAF protein-membrane interactions that identify specific lipid-protein fingerprints that enhance protein orientations viable for effector binding. MuMMI is a fully automated, ensemble-based multiscale approach connecting three resolution scales: (1) the coarsest scale is a continuum model able to simulate milliseconds of time for a 1 μm<sup>2</sup> membrane, (2) the middle scale is a coarse-grained (CG) Martini bead model to explore protein-lipid interactions, and (3) the finest scale is an all-atom (AA) model capturing specific interactions between lipids and proteins. MuMMI dynamically couples adjacent scales in a pairwise manner using machine learning (ML). The dynamic coupling allows for better sampling of the refined scale from the adjacent coarse scale (forward) and on-the-fly feedback to improve the fidelity of the coarser scale from the adjacent refined scale (backward). MuMMI operates efficiently at any scale, from a few compute nodes to the largest supercomputers in the world, and is generalizable to simulate different systems. As computing resources continue to increase and multiscale methods continue to advance, fully automated multiscale simulations (like MuMMI) will be commonly used to address complex science questions.
The adaptation of spike backpropagation delays in cortical neurons (2013)

We measured the action potential backpropagation delays in apical dendrites of layer V pyramidal neurons of the somatosensory cortex under different stimulation regimes that exclude synaptic involvement. These delays showed robust features and did not correlate to either transient change in the stimulus strength or low frequency stimulation of suprathreshold membrane oscillations. However, our results indicate that backpropagation delays correlate with high frequency (>10 Hz) stimulation of membrane oscillations, and that persistent suprathreshold sinusoidal stimulation injected directly into the soma results in an increase of the backpropagation delay, suggesting an intrinsic adaptation of the backpropagating action potential (bAP), which does not involve any synaptic modifications. Moreover, the calcium chelator BAPTA eliminated the alterations in the backpropagation delays, strengthening the hypothesis that increased calcium concentration in the dendrites modulates dendritic excitability and can impact the backpropagation velocity. These results emphasize the impact of dendritic excitability on bAP velocity along the dendritic tree, which affects the precision of the bAP arrival at the synapse during specific stimulus regimes, and is capable of shifting the extent and polarity of synaptic strength during suprathreshold synaptic processes such as spike time-dependent plasticity.
&lt;title&gt;Signal processing for robotically assisted laser photocoagulation of the retina&lt;/title&gt; (1999)

A new system for robotically assisted retinal surgery requires real-time signal processing of the reflectance signal from small targets on the retina. Laser photocoagulation is used extensively by ophthalmologists to treat retinal disorders such as diabetic retinopathy and retinal breaks. Currently, the procedure is performed manually and suffers from several drawbacks which a computer-assisted system could alleviate. Such a system is under development that will rapidly and safely place multiple therapeutic lesions at desired locations on the retina in a mater of seconds. This system provides real- time, motion-stabilized lesion placement for typical clinical irradiation times. A reflectance signal from a small target on the retina is used to derive high-speed tracking corrections to compensate for patient eye movement by adjusting the laser pointing angles. Another reflectance signal from a different small target on the retina is used to derive information to control the laser irradiation time which allows consistent lesion formation over any part of the retina. This paper describes the electro-optical system which dynamically measures the two reflectance signals, determines the appropriate reflectance parameters in real time, and controls laser pointing and irradiation time to meet the stated requirements.
Genetic and Antigenic Evidence Supports the Separation of<i>Hepatozoon canis</i>and<i>Hepatozoon americanum</i>at the Species Level (2000)

Recognition of Hepatozoon canis and Hepatozoon americanum as distinct species was supported by the results of Western immunoblotting of canine anti-H. canis and anti-H. americanum sera against H. canis gamonts. Sequence analysis of 368 bases near the 3' end of the 18S rRNA gene from each species revealed a pairwise difference of 13.59%.
Options for transport energy conservation in Pakistan (2014)

Increasing demand for mobility, expansion of the economy, and the realisation of new goals for development have caused tremendous growth in the transport sector of Pakistan. Consequently, transport's share of commercial energy consumption has been increasing and the transport sector has emerged as Pakistan's single largest consumer of petroleum products. Road transport's growth has been more swift and significant than other modes of transport. Opportunities exist to reduce the transport energy demand by switching to energy efficient modes of transport and by employing better management practices. This paper reviews the evolution of transport, patterns of energy demand and supply, and suggests measures to reduce the transport energy demand in Pakistan.
Mass spectrometry-based multi-attribute method in protein therapeutics product quality monitoring and quality control (2023)

The multi-attribute method (MAM), a liquid chromatography-mass spectrometry (LC-MS)-based peptide mapping method, has gained increased interest and applications in the biopharmaceutical industry. MAM can, in one method, provide targeted quantitation of multiple site-specific product quality attributes, as well as new peak detection. In this review, we focus on the scientific and regulatory considerations of using MAM in product quality attribute monitoring and quality control (QC) of therapeutic proteins. We highlight MAM implementation challenges and solutions with several case studies, and provide our perspective on the opportunities to use MS in QC for applications other than standard peptide mapping-based MAM.
Early development of small intestinal function. (2006)

<title>Abstract</title> To accommodate the rapid transition to external nutrient sources, the chicken small intestine goes through morphological, cellular and molecular changes towards the end of incubation. The weight of the intestine, as a proportion of embryonic weight, increases from approximately 1% at 17 days of incubation (17E) to 3.5% at hatch. At this time, the embryonic small intestinal villi are divided into two main developmental stages, which differ in both length and shape. Mucin-producing cells can be observed from 17E and at that time contain only acidic mucin. The activity and RNA expression of brush-border enzymes, which digest disaccharides and small peptides, and of major transporters (sodium-glucose transporter and ATPase) which are found at 15E, begin to increase at 19E (2 days prior to hatch), and increase further on the day of hatch. Although the digestive capacity begins to develop a few days before hatch, most of the development occurs post-hatch when the neonatal chick begins consuming feed. During the post-hatch period, the weight of the small intestine increases at a faster rate than body mass. Rapid enterocyte proliferation and differentiation occur. In addition the intestinal crypts, which begin to form at hatch, are clearly defined several days post-hatch, increasing in both cell number and size. Goblet cells produce acidic and neutral mucins in similar proportions. Studies have shown that feeding immediately post-hatch or even pre-hatch accelerates the functional development of the small intestine, while delayed access to external feed arrests the development of the small intestine's mucosal layer and changes mucin dynamics.
Experience in implementing a quality management system in a tuberculosis laboratory, Kisumu, Kenya (2015)

We implemented a quality management system (QMS) and documented our improvements in a tuberculosis (TB) laboratory in Kisumu, Kenya. After implementation of the QMS, a sustained reduction in culture contamination rates for solid (from 15.4% to 5.3%) and liquid media (from 15.2% to 9.3%) was observed, and waste from product expiry was reduced significantly. External quality assurance (EQA) results were satisfactory before and after QMS implementation, and a client survey after implementation revealed 98% satisfaction. The laboratory attained ISO 15189 accreditation in October 2013. The implementation of QMS facilitated the attainment of target quality indicators, reduced waste due to expiry and led to high client satisfaction.
Surface recombination velocity of highly doped <i>n</i>-type silicon (1996)

New experimental data for the minority-carrier surface recombination velocity of n-type silicon, Sp, are reported. The data, obtained from photoconductance decay measurements of the recombination currents corresponding to different phosphorus diffusions, include oxide-passivated, unpassivated and metal-coated surfaces. For the passivated case, Sp increases linearly with surface dopant density, ND, for dopant densities higher than 1×1018 cm−3, while for unpassivated (bare) and for metal-coated silicon Sp remains essentially constant, at about 2×105 cm/s and 3×106 cm/s, respectively. The experiments also allow for a determination of the apparent energy bandgap narrowing as a function of dopant density, ΔEgapp=14 meV [ln(ND/1.4×1017 cm−3)]. These surface recombination velocity and ΔEgapp data form, together with the dependences of minority-carrier lifetime, τp, and mobility, μp, used in the analysis, a consistent set of parameters that fully characterize highly doped n-type silicon.
Role of adenine nucleotides in the regulation of bacterial energy metabolism: theoretical problems and experimental pitfalls. (1990)

The effect of growth rate on ATP pool and adenylate energy charge (EC) value of Escherichia coli has been studied in batch culture on different media (mu max varying from 0.1 h-1 to 1.2 h-2) and in continuous culture at dilution rates (D = mu) from 0.045 h-1 to 0.310 h-1. Within the limits of error both ATP pool and EC values did not change with alterations in the relative growth rate of E. coli. The effect of in vivo EC values on experimental errors in ATP, ADP and AMP measurements with the luciferin-luciferase method, and, subsequently, on measurements of different ratios between adenylates, as in the case of adenylate kinase in vivo equilibrium, is discussed.
Low-Drift Optoelectronic Oscillator Based on a Phase Modulator in a Sagnac Loop (2017)

A low-drift optoelectronic oscillator (OEO) is developed and experimentally shown. In the proposed OEO, a fiber Sagnac interferometer, including an optical phase modulator (PM) and a nonreciprocal bias unit, functions as an intrinsically drift-free intensity modulator. The phase noise of the proposed OEO is modeled in phase space, which is verified by experiments. Phase noise and frequency stability of the photonically generated microwave signals are measured. The single-sideband phase noise of the generated microwave signal is -106.6 dBc/Hz at 10-kHz offset from the 10.833-GHz carrier, with 120-fs rms timing jitter integrated from 1 kHz to 10 MHz. Frequency drift measurements show ±0.85-ppm maximum fractional frequency deviation over 35 h, mainly caused by drift of the fiber delay line.
Immunotherapy of the BB Rat * (2019)

This chapter describes the use of the BB rat as an animal model of insulin-dependent diabetes mellitus (IDDM) and its use as a system in which various immunotherapeutic procedures can be tested. Immunotherapy for IDDM should be directed only at the components of immune system responsible for pancreatic beta cell destruction. The clinical appearance of disease in the diabetes prone BB rat is similar to that observed in children experiencing the acute onset of IDDM. Diabetes-resistant -BB/Wor rats were derived from diabetes-prone forebears, but have been brd for resistance to the disease. The large number of relevant immunological observations in BB rat suggest a correspondingly large number of potential targets towards which immunotherapeutic interventions can be directed. Available data suggest that the pancreatic beta cell of the BB rat is intrinsically normal. Removal of large amounts of blood from prediabetic diabetes-prone BB rats, originally undertaken for unrelated reasons, was found to decrease substantially the incidence of disease in the animals.