gebhart/patrepeval huggingface dataset:
Orientation of Back Reflection Laue Photographs: A Semi-Automated Approach (1975)

Computer simulation of back reflection Laue patterns now provides the means to plot Laue patterns for any crystal system in any orientation. This capability makes it possible to determine, rapidly and accurately, the orientation of single crystals and large grains in polycrystalline materials even in cases where little or no symmetry is displayed in the Laue photograph. A set of standard Laue patterns is first simulated to cover the stereographic triangle of the crystal being studied. The Laue photograph obtained from the crystal, or grain, is compared with the set of simulated Laue patterns. The pattern most similar to the photograph is used to determine the (HKL) values of three Laue spots. The (HKL) values of these spots and half their angular separations from the x-ray beam, along with the lattice constants, are used by a computer program to calculate the (HKL) value of the crystallographic plane perpendicular to the x-ray beam. A simulated Laue pattern can now be obtained in exactly the same orientation and it can be drawn directly to the scale of the Laue photograph. Thus the validity of the orientation can be easily verified by direct comparison. The (HKL) value of the crystallographic plane perpendicular to the x-ray beam can also be used to plot a stereographic projection of the crystal poles. Therefore, the complete orientation of the crystal can be determined.
<i>In situ</i>X-ray powder diffraction study of R<sub>1−<i>x</i></sub>Nd<sub><i>x</i></sub>AlO<sub>3</sub>(R = La, Pr) (2009)

At room temperature (RT) compounds RAlO 3 of the early rare-earth metals with R = La, Pr, Nd adopt rhombohedral structures (R 3 c), which transform into the cubic perovskite
Hypothalamic and Pituitary Enzymatic Degradation of Luteinizing Hormone-Releasing Hormone during the 4-Day Estrous Cycle of the Rat (1986)

Luteinizing hormone-releasing hormone (LHRH) degrading activity may be of physiological significance as a mechanism capable of partial regulation of hypothalamic LHRH release as well as LHRH levels at the gonadotroph. The possibility of cyclic fluctuations in LHRH-degrading activity was investigated in female rat hypothalami and pituitaries. These tissues were collected at selected time points during the 4-day estrous cycle, homogenized, and centrifuged at 100,000 g. Supernatants were incubated with synthetic LHRH, the reactions terminated, and the decapeptide and its products separated by high-performance liquid chromatography. Degradation of LHRH incubated with active cytosol was estimated by comparison of integrated LHRH peak area with that from incubations with heat-inactivated cytosol. Hypothalamic LHRH degradation was depressed during the latter hours of diestrus 2, a time during which the LHRH content in the hypothalamus has been reported to be increasing. From diestrus 24.00 h to proestrus 15.00 h, there was a significant increase in degrading activity. This was then followed by a decline from 15.00 to 18.00 h proestrus; at the time of the LH surge, the activity had not undergone significant increase in comparison to 18.00 h. Pituitary LHRH degradation was significantly increased during the 6-hour period preceding the surge, but was significantly depressed at the surge. The hypothalamic reduction in activity associated with diestrus 2 as well as the hypothalamic and pituitary reductions associated with proestrus may represent a permissive effect allowing increased LHRH accumulation in the hypothalamus and its prolonged action in the pituitary.(ABSTRACT TRUNCATED AT 250 WORDS)
Miscibility and complexation behavior of poly(cyanomethyl methacrylate) and poly(2‐cyanoethyl methacrylate) with tertiary amide polymers (1995)

Abstract The miscibility and complexation behavior of poly(cyanomethyl methacrylate) (PCYMMA) and poly(2‐cyanoethyl methacrylate) (PCYEMA) with various tertiary amide polymers was studied. PCYMMA and PCYEMA form interpolymer complexes with poly( N ‐methyl‐ N ‐vinylacetamide) (PMVAc) or poly( N ‐vinyl‐2‐pyrrolidone) (PVP) in tetrahydrofuran (THF) solutions. PCYMMA also forms complexes with poly( N,N ‐dimethylacrylamide) (PDMA) in THF solutions. However, PCYEMA does not form complexes with PDMA in THF solutions, but the THF‐cast blends are miscible over the entire composition range. Both PCYMMA and PCYEMA do not form complexes with poly(2‐ethyl‐2‐oxazoline) (PEOx) in THF solutions and are only miscible with PEOx when the blend contains greater than 60 wt % PCYMMA or 80 wt % PCYEMA. On the other hand, both PCYMMA and PCYEMA do not form complexes with PMVAc, PVP, or PDMA in N,N ‐dimethylformamide (DMF) solutions. The compositions of the complexes consist of simple mole ratios of the component polymers, and the glass‐transition temperatures of the complexes are higher than those of the DMF‐cast blends of similar compositions. Fourier‐transform infrared spectroscopy provides further evidence on the miscibility behavior through changes in the amide carbonyl absorption bands of each tertiary amide polymer in the blends as well as in the cyano absorption band of PCYEMA. © 1995 John Wiley & Sons, Inc.
Development of Pre-Crash Safety Technology for Large Trucks (2005)

As one of the key technologies to improve the safety of large trucks, pre-crash safety technology (PCS) was studied. PCS is the system which automatically activates the brake when a collision is unavoidable. From the accident analysis, it was determined that collisions with stationary vehicles and accidents on expressways would be considered in this study. To cope with the accidents on expressways where collision speeds are usually high, the PCS system needs to detect the objects and apply the brake from a long distance. To achieve this, the sensor should be tuned to enable long distance sensing. Generally this can result in difficulties to clearly divide real objects on the road and something on the roadside, especially at curves. If the activation of the system can be limited to only on expressways, there is a possibility that this can be improved, because on the expressways traffic lanes are wider and thus roadside objects are a little far from the center of the traffic lane, and the radii of curves are more than a certain value. Activation timing of the brake should be decided so that the driver does not place too much trust in the system. For this reason, the brake should not be activated when there is certain possibility that the collision is avoidable.
Millimeter wave channel model and system design considerations (2015)

In order to exploit millimeter wave (mmWave) bands for 5G communications, challenges mainly due to blockage and strong dependency on beamforming operation need to be overcome. In this work, we address some of the fundamental issues related to the use of mmWave bands for 5G communications, from propagation channel characteristics and modeling to the implications on system and network architecture design. A statistical mmWave channel model considering cluster-level spatial/temporal correlation is proposed. System-level simulation results based on the proposed model demonstrate the channel characteristics and system performance. Following that, key techniques in enabling mmWave system operation are discussed. Although we believe that mmWave bands can be utilized in 5G networks, significant efforts and time are needed in order to complete the air interface, device and network design which is shown to be quite different from the existing cellular design.
Cerebral hemodynamics and metabolism in pseudotumor cerebri (1978)

A comprehensive analysis of cerebral hemodynamics and metabolism was carried out in 14 patients with pseudotumor cerebri. Tracer techniques were employed to measure cerebral blood flow (CBF) and vascular reactivity to acute changes in arterial carbon dioxide tension and blood pressure, cerebral blood volume (CBV), and the cerebral metabolic rate for oxygen and glucose. There was a small reduction (p less than 0.01) in CBF (44 +/- 7 ml/100 gm/min; normal, 54 +/- 9) with normal vascular reactivity; an increase (p less than 0.005) in CBV (4.8 +/- 0.8 ml/100 gm; normal, 3.6 +/- 0.5), and normal cerebral metabolism. We conclude that an abnormality of the cerebral microvasculature is responsible for an elevation in CBV, but the intracranial hypertension can be explained only by tissue swelling due to an increase in water content. The relationship between the vascular abnormality and the tissue swelling remains to be defined.
Extracellular ATP regulates transcervical permeability by modulating two distinct paracellular pathways (1997)

Extracellular ATP stimulates a biphasic change in transepithelial electrical resistance (RTE) across cultures of human cervical epithelial cells: an acute decrease (phase I), followed by a delayed increase in resistance (phase II). The objective of this study was to determine the contributions of changes in the lateral intercellular space resistance (RLIS) and the tight junctional resistance (RTJ) to the changes in RTE. Phase I and phase II effects were uncoupled by treatment with 1,2-bis(2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (BAPTA)-acetoxymethyl ester, which blocks the ATP-induced increases in cytosolic Ca2+ and abolishes phase I. BAPTA-loaded cells differed from control cells in that 1) phase I began when ATP was added, in contrast to a delay of 1.5-3.5 min in phase II, 2) phase I decreases in RLIS followed a simple exponential pattern, in contrast to the complex kinetics of phase II, and 3) the magnitude of phase II varied between 20 and 100% for increases of RTJ in day 2-6 cultures; the phase I decrease of 50% in RLIS was unrelated to different experimental conditions. These results indicate that phase I and phase II are induced simultaneously and independently by ATP, and they contribute to the total changes in RTE. We conclude that ATP regulation of RLIS and RTJ may be important mechanisms of modulating cervical mucus production in vivo.
Analysis of Microscale Transport for BioMEMS (2004)

Micron-resolution Particle Image Velocimetry (micro-PIV) is used to measure fluid motion in 30 x 300 micron channels. The results indicate that the no-slip boundary condition may not necessarily hold for hydrophobic surfaces in micro and nanochannels. Micro-PIV is also used to measure AC electrokinetic flow. Microscale mixing can be induced by precisely controlled 20 micron vortices. Finite element simulations are used to show that these vortices can be used in Bio-MEMS to enhance receptor/ligand binding on functionalized surfaces by a factor of four to six. SLIP FLOW BACKGROUND At the macroscopic level, it is well accepted that the boundary condition for a viscous fluid at a solid wall is “no-slip”, i.e. the fluid velocity matches the velocity of the solid boundary. While the no-slip boundary condition has been proven experimentally to be accurate for a number of macroscopic flows, it remains an assumption that is not based on physical principles. In fact, nearly two hundred years ago Navier (1823) proposed a general boundary condition that incorporates the possibility of fluid slip at a solid boundary. Navier’s proposed boundary condition assumes that the velocity, w u , at a solid surface is
<title>Active contours applied to the shape and motion analysis of amoeba</title> (2001)

We present a method based on active contours to track and segment biological cells in large image sequences obtained by video-microscopy. This task is facilitated by good time resolution and global contrast, but important obstacles are the low contrast boundary deformations known as pseudopods, as well as cell aggregations and divisions. In order to allow better detection of local boundary deformations, we adopted the gradient vector flow (GVF) model of Xu and Prince, which is defined as the steady-state solution of a reaction-diffusion problem. We discuss an undesirable effect of boundary competition in the GVF that can lead to incorrect segmentations for grey-level images. We propose to replace the steady-state solution by a transient solution of the diffusion equation to alleviate this effect, which also allows significant gains in computation time. To enhance pseudopods over texture features, we use a binary edge map obtained from a Canny-Deriche filter followed by hysteresis thresholding. We use topological operators to efficiently detect intersections and maintain contour separation between aggregating cells. Cell divisions are automatically handled by this method. We discuss limits and possible improvements of this work.
Simple method for eliminating the warming-up time of an Antares cw mode-locked Nd:YLF laser (1993)

Mode locking of a cw Nd:YLF laser is sensitive to cavity-length mismatch. When a cw mode-locked Nd:YLF laser is turned on the power dissipation from the lamps causes a slow change in the cavity length because of heating of mechanical resonator parts. A method is presented to eliminate these warming-up effects.
Genomic Analysis of the Unfolded Protein Response in Arabidopsis Shows Its Connection to Important Cellular Processes[W] (2003)

We analyzed the breadth of the unfolded protein response (UPR) in Arabidopsis using gene expression analysis with Affymetrix GeneChips. With tunicamycin and DTT as endoplasmic reticulum (ER) stress-inducing agents, we identified sets of UPR genes that were induced or repressed by both stresses. The proteins encoded by most of the upregulated genes function as part of the secretory system and comprise chaperones, vesicle transport proteins, and ER-associated degradation proteins. Most of the downregulated genes encode extracellular proteins. Therefore, the UPR may constitute a triple effort by the cell: to improve protein folding and transport, to degrade unwanted proteins, and to allow fewer secretory proteins to enter the ER. No single consensus response element was found in the promoters of the 53 UPR upregulated genes, but half of the genes contained response elements also found in mammalian UPR regulated genes. These elements are enriched from 4.5- to 15-fold in this upregulated gene set.
A comparison of feature and pose-based mapping using vision, inertial and GPS on a UAV (2011)

This paper presents and compares two different approaches to integrating sensor information from an Inertial Measuring Unit (IMU), Global Positioning System (GPS) receiver and monocular vision camera mounted to a low-flying Unmanned Aerial Vehicle (UAV) for building large-scale 3D terrain reconstructions. Both approaches utilise a statistically optimal bundle adjustment formulation that incorporates Vision, IMU and GPS observations into the map and pose optimisation process. Our first approach employs a novel pose-only formulation that optimises relative camera poses based on vision feature matches between frames, while incorporating IMU and GPS information. Our approach is related to, but differs from existing pose-graph techniques by formulating a set of 1D epipolar constraints for features matched between two camera frames, rather than minimising 4D feature re-projection errors, or marginalising feature states. We compare results of the method to a second approach which estimates both 3D features and poses together, using airborne vision, IMU and GPS data collected in an ecology mapping application. The results demonstrate a reduction in the computational complexity during optimisation for the pose-only approach, while producing equivalent accuracy in the reconstructed 3D terrain map.
Effects of Phorbol Esters and Cytokines (Interleukin-2,-4, and -6) on the Proliferation and Surface Phenotype of Epstein-Barr Virus Immortalised Human B Lymphocytes (1992)

Epstein-Barr virus (EBV)-induced in vitro infection of peripheral blood mononuclear cells (PBMCs) leads to a polyclonal proliferation and immortalisation of B lymphocytes. In the present study we determined the effects of three different cytokines, interleukin-2 (IL-2), interleukin-4 (IL-4) and interleukin-6 (IL-6), and the tumour promoting phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA) on EBV-immortalised B lymphocytes. These factors have known activities on normal B cells. IL-4 and IL-6 increased significantly EBV-B cell proliferation after 3 and 5 days of culture, where IL-2 had no effect. The effect of IL-4 and IL-6 on EBV-B cells was abolished after pre-incubation with anti-IL-4 and anti-IL-6 neutralising antisera, respectively. TPA induced a dose dependent inhibition of proliferation both in serum free and 10% fetal calf serum (FCS) supplemented culture medium. Combinations of TPA and interleukins did not restore lymphoblastoid cell proliferation to background levels. All possible combinations of the three cytokines showed no synergistic or antagonistic effect on proliferation. TPA induced significant phenotypic changes of EBV immortalised B lymphocytes, by increasing IL-2 receptor (IL-2R) expression and decreasing CD20 and CD23 antigen expression. Other B cell differentiation antigens; HLA-DR, CD19, and transferrin receptor (CD71), did not demonstrate significant changes. A dose dependent inhibition of CD21 and increase in CD22 expression was observed in 2 out of 3 lymphoblastoid cell lines tested.
A SiGe-BiCMOS Wideband (2–22 GHz) Active Power Divider/Combiner Circuit Supporting Bidirectional Operation (2016)

A power divider/combiner circuit, which simultaneously achieves wide bandwidth, flat gain characteristics, and bidirectional operation, is proposed for multichannel broadband system applications. The proposed circuit utilizes cascode-based bidirectional amplifier cores, which steer the operation modes between a divider and a combiner depending on the control input, and a two-stage distributed-amplifier topology with artificial transmission lines. Implemented in a 130-nm silicon-germanium BiCMOS technology platform, the proposed divider/combiner provides the advantage of seamless integration with digital control blocks. The power divider/combiner exhibits the flat in-band gain of 9 dB and the operational bandwidth of 2-22 GHz, which covers S-, C-, X-, and Ku-bands. In addition, it shows the amplitude imbalance of 0.8 dB, the phase imbalance of 3.5°, the port-to-port isolation of 22 dB, the output 1-dB compression point of 3 dBm, and good impedance matching under 100-mW dc power consumption.
Energy Efficient Architecture for Green Handsets in Next Generation IP-Based Wireless Networks (2011)

Next generation wireless networks are expected to integrate harmoniously in an IP-based core network. Such paradigm shift will amalgamate several distinct radio access technologies into a unifying composite network. However, this creates a fundamental problem for handsets which manifests in high power consumption due to network discovery that is typically carried out by performing scanning operations. Since handsets are naturally constrained by its battery lifetime, this paper analyzes the impact of network discovery on the handsets' power consumption from the network architecture perspective. Particular, we focus on network discovery through the scanning (information pulling) and broadcasting (information pushing) approaches. In this context, we extend a unified analytical model to evaluate the performance comparison of energy efficiency between the legacy and terminal oriented network-assisted (TONA) architectures. Comprehensive numerical and simulation results show that the TONA handover architecture provides an energy saving of 8 35% to promote green handsets under various network load and scanning intervals.
Stereoselective synthesis of oxazolidinonyl-fused piperidines of interest as selective muscarinic (M<sub>1</sub>) receptor agonists: a novel M<sub>1</sub> allosteric modulator (2016)

Syntheses of (1RS,2SR,6SR)-2-alkoxymethyl-, 2-hetaryl-, and 2-(hetarylmethyl)-7-arylmethyl-4,7-diaza-9-oxabicyclo[4.3.0]nonan-8-ones, of interest as potential muscarinic M1 receptor agonists, are described. A key step in the synthesis of (1RS,2SR,6SR)-7-benzyl-6-cyclobutyl-2-methoxymethyl-4,7-diaza-9-oxabicyclo[4.3.0]nonan-8-one, was the addition of isopropenylmagnesium bromide to 2-benzyloxycarbonylamino-3-tert-butyldimethylsilyloxy-2-cyclobutylpropanal. This gave the 4-tert-butyldimethylsilyloxymethyl-4-cyclobutyl-5-isopropenyloxazolidinone with the 5-isopropenyl and 4-tert-butyldimethylsilyloxymethyl groups cis-disposed about the five-membered ring by chelation controlled addition and in situ cyclisation. This reaction was useful for a range of organometallic reagents. The hydroboration-oxidation of (4SR,5RS)-3-benzyl-4-(tert-butyldimethylsilyloxymethyl)-4-cyclobutyl-5-(1-methoxyprop-2-en-2-yl)-1,3-oxazolidin-2-one gave (4SR,5RS)-3-benzyl-4-(tert-butyldimethylsilyloxymethyl)-4-cyclobutyl-5-[(SR)-1-hydroxy-3-methoxyprop-2-yl]-1,3-oxazolidin-2-one stereoselectively. 4,7-Diaza-9-oxabicyclo[4.3.0]nonan-8-ones with substituents at C2 that could facilitate C2 deprotonation were unstable with respect to oxazolidinone ring-opening and this restricted both the synthetic approach and choice of 2-heteroaryl substituent. The bicyclic system with a 2-furyl substituent at C2 was therefore identified as an important target. The addition of 1-lithio-1-(2-furyl)ethene to 2-benzyloxycarbonylamino-3-tert-butyldimethylsilyloxy-2-cyclobutylpropanal gave (4SR,5RS)-4-tert-butyldimethylsilyloxymethyl-4-cyclobutyl-5-[1-(2-furyl)ethenyl]-1,3-oxazolidinone after chelation controlled addition and in situ cyclisation. Following oxazolidinone N-benzylation, hydroboration at 35 °C, since hydroboration at 0 °C was unexpectedly selective for the undesired isomer, followed by oxidation gave a mixture of side-chain epimeric alcohols that were separated after SEM-protection and selective desilylation. Conversion of the neopentylic alcohols into the corresponding primary amines by reductive amination, was followed by N-nosylation, removal of the SEM-groups and cyclisation using a Mitsunobu reaction. Denosylation then gave the 2-furyloxazolidinonyl-fused piperidines, the (1RS,2SR,6SR)-epimer showing an allosteric agonistic effect on M1 receptors. Further studies resulted in the synthesis of other 2-substituted 4,7-diaza-9-oxabicyclo[4.3.0]nonan-8-ones and an analogous tetrahydropyran.
ChemInform Abstract: The Tandem Insertion of Allyl Carbenoids and Aldehydes or Ketones into Zirconacyclopentanes: Variation of the Allyl Moiety and Functionalization of the Final Carbon‐Zirconium Bond. (1995)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.