gebhart/patrepeval huggingface dataset:
Synchronous helical pulse sequences in magic-angle spinning nuclear magnetic resonance: Double quantum recoupling of multiple-spin systems (2000)

Some general principles of radio-frequency pulse sequence design in magic-angle spinning nuclear magnetic resonance are discussed. Sequences with favorable dipolar recoupling properties may be designed using synchronous helical modulations of the space and spin parts of the spin Hamiltonian. The selection rules for the average Hamiltonian may be written in terms of three symmetry numbers, two defining the winding numbers of the space and spin helices, and one indicating the number of phase rotation steps in the radio-frequency modulation. A diagrammatic technique is used to visualize the space-spin symmetry selection. A pulse sequence C1445 is designed which accomplishes double-quantum recoupling using a low ratio of radio frequency field to spinning frequency. The pulse sequence uses 14 radio frequency modulation steps with space and spin winding numbers of 4 and 5, respectively. The pulse sequence is applied to the double-quantum spectroscopy of C313-labeled L-alanine. Good agreement is obtained between the experimental peak intensities, analytical results, and numerically exact simulations based on the known molecular geometry. The general symmetry properties of double quantum peaks in recoupled multiple-spin systems are discussed. A supercycle scheme which compensates homonuclear recoupling sequences for chemical shifts is introduced. We show an experimental double-quantum C13 spectrum of [U–13C]–L-tyrosine at a spinning frequency of 20.000 kHz.
A Re-Examination of the Relative Turgidity Technique for Estimating Water Deficits in Leaves (1962)

The relative turgidity technique consists in comparing the initial and turgid water contents, on a percentage basis, of disks punched from leaves, the turgid water content being obtained by floating the disks on water.
Severe dietary restriction initiated in aged rats: evidence for poor adaptation in terms of protein metabolism and intestinal functions (1999)

Aged rats clearly exhibit a defect of adaptation to long-term DR initiated at an advanced age. Severe DR leads to malnutrition, which becomes of major importance after 12 weeks, in particular at the intestine level. Hence, application of these experimental results to elderly, malnourished people may contribute to a better knowledge of denutrition-induced disorders.
Interpretation and Use of Natriuretic Peptides in Non-Congestive Heart Failure Settings (2010)

Natriuretic peptides (NPs) have been found to be useful markers in differentiating acute dyspneic patients presenting to the emergency department (ED) and emerged as potent prognostic markers for patients with congestive heart failure (CHF). The best-established and widely used clinical application of BNP and NT-proBNP testing is for the emergent diagnosis of CHF in patients presenting with acute dyspnea. Nevertheless, elevated NPs levels can be found in many circumstances involving left ventricular (LV) dysfunction or hypertrophy; right ventricular (RV) dysfunction secondary to pulmonary diseases; cardiac inflammatory or infectious diseases; endocrinology diseases and high output status without decreased LV ejection fraction. Even in the absence of significant clinical evidence of volume overload or LV dysfunction, markedly elevated NP levels can be found in patients with multiple comorbidities with a certain degree of prognostic value. Potential clinical applications of NPs are expanded accompanied by emerging reports regarding screening the presence of secondary cardiac dysfunction; monitoring the therapeutic responses, risk stratifications and providing prognostic values in many settings. Clinicians need to have expanded knowledge regarding the interpretation of elevated NPs levels and potential clinical applications of NPs. Clinicians should recognize that currently the only reasonable application for routine practice is limited to differentiation of acute dyspnea, rule-out-diagnostic-tests, monitoring of therapeutic responses and prognosis of acute or decompensated CHF. The rationales as well the potential applications of NPs in these settings are discussed in this review article.
EBC Slurry Infiltrated Matrix/Coatings For Woven SiC/SiC Composites (2018)

This chapter examines the use of ceramic matrix composites (CMCs) in high temperature applications such as hot section and exhaust components of the turbine and hypersonic engines. Slurries were infiltrated into a series of 2D woven porous Chemical Vapor Infiltrated (CVI) SiC/SiC composites with different porosity as part of an experiment. The CMC specimen (woven sample) was placed in holder in the lower chamber. The slurry was injected through a funnel into the upper chamber and held by a closed valve. Vacuum applied to the lower chamber reduced air trapped inside of CMC specimen. The infiltration procedure was repeated several times until all pores were filled by solid particles as much as possible and a layer of particle cake formed on the surface of the sample. Excess material was brushed off of the surface and infiltrated specimen was dried in air and sintered in air in a high-temperature furnace. The porometry of all three batches SiC/SiC composites were studied before and after slurry infiltration, including pore structure, permeability and pore size distribution.
Understanding and Quantifying Arc Flash Hazards in the Mining Industry (2011)

Arc flash generally refers to the dangerous exposure to thermal energy released by an arcing fault on an electrical power system, and in recent years, arc flash hazards have become a prominent safety issue in many industries. This problem, however, has not been effectively addressed in the mining industry. Mine Safety and Health Administration (MSHA) data for the period 1990 through 2001 attribute 836 injuries to “noncontact electric arc burns,” making them the most common cause of electrical injury in mining. This paper presents results from several elements of a recent National Institute for Occupational Safety and Health study of arc flash hazards in mining and provides information and recommendations that can help reduce these injuries. The characteristics of past arc flash injuries in mining are first outlined, such as the electrical components and work activities involved (based on MSHA data). This is followed by a review of important concepts and terminology needed to understand this hazard. Next, methods for identifying, measuring, and managing arc flash hazards on a power system are covered, with emphasis on recommendations found in NFPA 70E, Standard for Electrical Safety in the Workplace. Finally, results are presented from a detailed arc flash hazard analysis performed on a sample mine electrical power system using IEEE 1584-2004a, focusing on components and locations presenting severe hazards, as well as engineering solutions for reducing the risk to personnel.
Acetylene-containing highly birefringent rod-type reactive liquid crystals based on 2-methylhydroquinone (2017)

New highly birefringent reactive liquid crystal materials based on the 2-methylhydroquinone core were designed and synthesised. Rod-type liquid crystal compounds bearing photo-crosslinkable reactive group of acryloyl, methacryloyl, cinnamoyl, furylacryloyl group were synthesised by introducing acetylene groups via Sonogashira coupling to obtain high birefringence, and lateral groups such as fluoro and methyl to adjust the temperature of the liquid crystal phase. The synthesised compounds were characterised using nuclear magnetic resonance spectroscopy, mass spectrometry and elemental analysis. In addition, their thermal behaviour was investigated using differential scanning calorimetry and polarised optical microscopy. After aligning the synthesised compounds, liquid crystal films were prepared by photo-irradiation. Photo-elastic modulator results showed that the obtained liquid crystal films had high birefringence (Δn) values of 0.32–0.40.
Depression of Human Neutrophil Motility by Influenza Virus In Vitro (1977)

After in vitro treatment of human peripheral neutrophils for 60 min at 37°C with purified influenza A virus, their random locomotion (no chemoattractant), chemokinesis (migration in the presence of a chemoattractant without a gradient), and chemotaxis were depressed, as determined by a modification of the Boyden method. The inhibition was accentuated by the presence of human serum devoid of antibodies to the virus. A strain of influenza B virus did not depress neutrophil motility at the same concentration and agglutinated the neutrophils at higher concentrations. Antiserum treatment partly abolished the inhibitory activity of the influenza virus. Inactivation of the virus infectivity with Tween 80 and ether did not change the ability of the virus to inhibit neutrophil motility. Bacterial neuraminidase did not inhibit neutrophil motility. Pretreatment of neutrophils with amantadine hydrochloride, which has been reported to block viral replication in its early stages, did not modify the depression of neutrophil motility by influenza A virus. The results give additional support to the suggested mechanism of depressed neutrophil function as a cause of bacterial superinfection after influenza.
Sources and Distribution of Organic Compounds Using Passive Samplers in Lake Mead National Recreation Area, Nevada and Arizona, and Their Implications for Potential Effects on Aquatic Biota (2010)

The delineation of lateral and vertical gradients of organic contaminants in lakes is hampered by low concentrationsand nondetection of many organic compounds in water. Passive samplers (semipermeable membrane devices [SPMDs] and polar organic chemical integrative samplers [POCIS]) are well suited for assessing gradients because they can detect synthetic organic compounds (SOCs) at pg L(-1) concentrations. Semi-permeable membrane devices and POCIS were deployed in Lake Mead, at two sites in Las Vegas Wash, at four sites across Lake Mead, and in the Colorado River downstream from Hoover Dam. Concentrations of hydrophobic SOCs were highest in Las Vegas Wash downstream from waste water and urban inputs and at 8 m depth in Las Vegas Bay (LVB) where Las Vegas Wash enters Lake Mead. The distribution of hydrophobic SOCs showed a lateral distribution across 10 km of Lake Mead from LVB to Boulder Basin. To assess possible vertical gradient SOCs, SPMDs were deployed at 4-m intervals in 18 m of water in LVB. Fragrances and legacy SOCs were found at the greatest concentrations at the deepest depth. The vertical gradient of SOCs indicated that contaminants were generally confined to within 6 m of the lake bottom during the deployment interval. The high SOC concentrations, warmer water temperatures, and higher total dissolved solids concentrations at depth are indicative of a plume of Las Vegas Wash water moving along the lake bottom. The lateral and vertical distribution of SOCs is discussed in the context of other studies that have shown impaired health of fish exposed to SOCs.
Phase and group delay calibration of a very long baseline interferometer by East Coast VLBI Group (1980)

Precisely timed pulses injected into the input of each receiver are used to calibrate the phase and group delay through each interferometer terminal. The short duration pulses are generated at a 1 MHz rate directly from the output of the frequency standard. The pulses are injected into the receiver at a level low enough to produce less than one percent increase in system temperature, yet can be extracted during processing with a high enough signal to noise ratio to determine the phase of the calibration rails within 1 degree in 1 second of integration. The calibration system also includes precise cable measurement electronics and a pulse echo for clock synchronization.
UTILITY OF A GENERAL PROGNOSTIC SCORE IN IDENTIFYING PATIENTS WITH POOR OUTCOMES AFTER AORTIC VALVE REPLACEMENT (2018)

The 2017 American College of Cardiology guidelines recommend consideration of life expectancy during aortic valve replacement (AVR) evaluation; however, how to estimate prognosis remains uncertain. We evaluated whether a popular general prognostic score, the Lee index (JAMA 2006), could aid in identifying patients with limited life expectancy who may not benefit from AVR. We prospectively enrolled 246 older patients undergoing surgical or transcatheter AVR at an academic center and assessed their ability to perform activities of daily activity and physical tasks over 12 months. The Lee index (range: 0–41) was calculated before surgery. Poor outcome was defined as death, or New York Heart Association Class III or IV with functional decline over 12 months. Of 91 surgical and 137 transcatheter patients with available outcome data, the mean Lee index score was 9.2 in surgical patients (range: 3–17) and 13.4 in transcatheter patients (range: 7–23). In the combined cohort, the risk of poor outcome increased with higher risk score quartiles (6.8%, 17.9%, 20.0%, 34.0%; p-for-trend<0.001). A similar trend was observed in the surgical patients (2.1%, 4.0%, 15.4%, 20.0%; p-for-trend=0.05). In comparison, no such trend existed in transcatheter patients (27.3%, 29.0%, 31.3%, 35.4%; p-for-trend=0.42). Our results suggest that while a prognostic model developed from the general population may be useful for surgical AVR patients, it has limited utility in identifying patients undergoing transcatheter AVR, with a higher burden of comorbidity, frailty, and functional limitations. Thus, better prognostic tools are needed to guide decisions for this specific population.
The Proteome of the Dentate Terminal Zone of the Perforant Path Indicates Presynaptic Impairment in Alzheimer Disease (2019)

Synaptic dysfunction is an early pathogenic event in Alzheimer disease (AD) that contributes to network disturbances and cognitive decline. Some synapses are more vulnerable than others, including the synapses of the perforant path, which provides the main excitatory input to the hippocampus. To elucidate the molecular mechanisms underlying the dysfunction of these synapses, we performed an explorative proteomic study of the dentate terminal zone of the perforant path. The outer two-thirds of the molecular layer of the dentate gyrus, where the perforant path synapses are located, was microdissected from five subjects with AD and five controls. The microdissected tissues were dissolved and digested by trypsin. Peptides from each sample were labeled with different isobaric tags, pooled together and pre-fractionated into 72 fractions by high-resolution isoelectric focusing. Each fraction was then analyzed by liquid chromatography-mass spectrometry. We quantified the relative expression levels of 7322 proteins, whereof 724 showed significantly altered levels in AD. Our comprehensive data analysis using enrichment and pathway analyses strongly indicated that presynaptic signaling, such as exocytosis and synaptic vesicle cycle processes, is severely disturbed in this area in AD, whereas postsynaptic proteins remained unchanged. Among the significantly altered proteins, we selected three of the most downregulated synaptic proteins; complexin-1, complexin-2 and synaptogyrin-1, for further validation, using a new cohort consisting of six AD and eight control cases. Semi-quantitative analysis of immunohistochemical staining confirmed decreased levels of complexin-1, complexin-2 and synaptogyrin-1 in the outer two-thirds of the molecular layer of the dentate gyrus in AD. Our in-depth proteomic analysis provides extensive knowledge on the potential molecular mechanism underlying synaptic dysfunction related to AD and supports that presynaptic alterations are more important than postsynaptic changes in early stages of the disease. The specific synaptic proteins identified could potentially be targeted to halt synaptic dysfunction in AD.
ARMA feeding techniques for isoflux coverage from a micro satellite (2017)

This paper deals with the design of a new reconfigurable beam antenna used to improve the efficiency of spatial telemetry links on Nano-Satellite. This agile beam antenna is not built on the well-known array concept AESA (Agile Electronically Scanned Array) but using a new one called ARMA (Agile Matrix Radiating Antenna); MARPEM in French. In this paper there is the design of the circularly polarized matrix antenna, the generation of two beam forming modes, the design of the distribution circuit and the polarization circuits.
A New Defined Lower Bit Rate AMR Mode in GSM and WCDMA Networks (2007)

Adaptive multi-rate (AMR) codec can adaptively select one of eight modes according to the channel condition or the system load. AMR allows making a trade-off between voice capacity and the voice quality. In GSM networks, when the channel condition is worse than the threshold, the voice quality is unacceptable even using the lowest rate mode (4.75 kbps). In this paper, by compressing the AMR frame, a new defined lower bit rate AMR mode with 3.95 kbps is proposed to guarantee the voice quality in this case. The proposed mode is completely compatible with the specified AMR codec in standard. Moreover, this mode can be adopted in WCDMA networks. Compared with 12.2 kbps mode, this new one can increase the capacity by 135% and increase the coverage gain by 2.6 dB.
ELECTRICAL AND OPTICAL CHARACTERIZATION OF POLYMER NANOCOMPOSITES SWELLING (2008)

In this work, polymer layers used in the fabrication of chemical sensors are characterized by means of an optical method based on white light interferometry. The study focuses on poly (hydroxy ethyl methacrylate) (PHEMA) and on nanocomposite Carbon black/PHEMA layers commonly used in chemical sensor technology for VOCs measurements. The response of nanocomposite PHEMA/CB layer upon exposure to vapour solvents is investigated in terms of film expansion and compared to the swelling properties of the PHEMA layer.
Protocols for Culturing and Imaging a Human Ex Vivo Osteochondral Model for Cartilage Biomanufacturing Applications (2019)

Cartilage defects and diseases remain major clinical issues in orthopaedics. Biomanufacturing is now a tangible option for the delivery of bioscaffolds capable of regenerating the deficient cartilage tissue. However, several limitations of <i>in vitro</i> and experimental animal models pose serious challenges to the translation of preclinical findings into clinical practice. <i>Ex vivo</i> models are of great value for translating <i>in vitro</i> tissue engineered approaches into clinically relevant conditions. Our aim is to obtain a viable human osteochondral (OC) model to test hydrogel-based materials for cartilage repair. Here we describe a detailed step-by-step framework for the generation of human OC plugs, their culture in a perfusion device and the processing procedures for histological and advanced microscopy imaging. Our <i>ex vivo</i> OC model fulfils the following requirements: the model is metabolically stable for a relevant culture period of 4 weeks in a perfusion bioreactor, the processing procedures allowed for the analysis of 3 different tissues or materials (cartilage, bone and hydrogel) without compromising their integrity. We determined a protocol and the settings for a non-linear microscopy technique on label free sections. Furthermore, we established a clearing protocol to perform light sheet-based observations on the cartilage layer without the need for tedious and destructive histological procedures. Finally, we showed that our OC system is a clinically relevant in terms of cartilage regeneration potential. In conclusion, this OC model represents a valuable preclinical <i>ex vivo</i> tool for studying cartilage therapies, such as hydrogel-based bioscaffolds, and we envision it will reduce the number of animals needed for <i>in vivo</i> testing.
Racemic and optically active tocopherol analogues with a modified side chain: Synthesis and biological activity (Review) (2007)

Information on the synthesis and biological activity of natural and synthetic analogues of alpha-tocopherol with a modified side chain is systematized. These compounds are of interest as vitamin E metabolites, hydrophilic antioxidants, and precursors of drugs with combined pharmacological properties useful in therapy of pathological disorders caused by oxidative stress.
Photoconductance Measurements on Thin-Film Crystalline Silicon p–n Diodes (2010)

We present photoconductance measurements of polycrystalline silicon thin-film p–n diodes on glass. The measurements were conducted with the WCT-100 photoconductance instrument using a pulsed high-energy 808-nm laser as the illumination source rather than a flash lamp, and a variable-gain transimpedance amplifier connected to the photodetector rather than a single resistor. By averaging ten thousand 30-ms pulses, the signal-to-noise ratio was made sufficiently high that a genuine photoconductance signal could be detected over 1–2 orders of magnitude. Each measurement took 5 minutes. Complications that relate to sample heating, carrier mobilities, depletion region modulation, and trapping are addressed.
Site-selective Ru-catalyzed C–H bond alkenylation with biologically relevant isoindolinones: a case of catalyst performance controlled by subtle stereo-electronic effects of the weak directing group (2019)

A general regio- and site-selective ruthenium-catalyzed C–H bond alkenylation with the biologically relevant isoindolinone fragment serving as a weak directing group is presented.
Imaging alone versus microelectrode recording–guided targeting of the STN in patients with Parkinson’s disease (2018)

According to the present analysis, approximately 80% of electrodes were appropriately targeted using imaging alone. In the other 20%, imaging alone led to suboptimal targeting that could be corrected by a trajectory course correction guided by the acquired MER data. The authors' results suggest that preoperative imaging is insufficient to obtain optimal results in all patients undergoing STN DBS.
Mutating protein kinase cAMP-binding sites into cGMP-binding sites. Mechanism of cGMP selectivity. (1991)

The cAMP-dependent protein kinase contains two different cAMP-binding sites referred to as the slow and fast sites. Mutation of Ala-334 to a threonine in the slow site of the bovine type I regulatory subunit created a site with marked increase in cGMP affinity without changing cAMP affinity (Shabb, J. B., Ng. L., Corbin, J. D. (1990) J. Biol. Chem. 265, 16031-16034). The corresponding fast site residue (Ala-210) was changed to a threonine by oligonucleotide-directed mutagenesis, and a double mutant containing a threonine in each site was also made. Holoenzymes were formed from native catalytic subunit and each recombinant regulatory subunit. The fast site mutant holoenzyme exhibited an improved cGMP activation constant and an impaired cAMP activation constant. The double mutant cGMP/cAMP selectivity was 200-fold greater than that of wild-type holoenzyme, making it as responsive to cGMP as native cGMP-dependent protein kinase. The increased intrinsic binding energies of mutated sites for cGMP were 2.7-3.0 kcal mol-1, consistent with the presence of an extra hydrogen bond. Cyclic nucleotide analog studies implied that this hydrogen bond was between the threonine hydroxyl and the 2-amino of cGMP. Comparisons of amino acid sequences and cyclic nucleotide specificities suggested that the Ala/Thr difference may also impart cAMP/cGMP binding selectivity to related proteins such as cyclic nucleotide-gated ion channels.