gebhart/patrepeval huggingface dataset:
Discrimination of weeds in brassica crops using optical spectral reflectance and leaf texture analysis (1999)

Optical spectral reflectance and image analysis techniques were investigated as possible solutions to discriminate crop and weed plants. The range of pants included two brassica crop species, a cereal crop and eight weed species. Spectral signatures were obtained form optical reflectance measurement taken with a spectrophotometer in reflectance mode in the region between 700 and 1350 nm. Algorithms were developed based on multivariate statistical analysis of the plant reflectance spectra. By minimizing wavebands of interest for certain crop/weed combinations, better than 95 percent discrimination accuracy was obtained for only two or three waveband measures. Using filters at these wavebands it was possible to easily segregate corp from weed plants in images. Discrimination on the basis of leaf texture was investigated using textural signatures for whole leaves derived from a gray level co-occurrence matrix of nearest- neighbor pixel intensity. Textural features of leaves were expressed in the form of feature vectors comprising nine textural parameters extracted from the co-occurrence matrix. A numerical Bayesian classifier was used to classify leaves based on minimum distance between a mean feature vector determined form a training set and the test feature vector. A mean discrimination accuracy of 90 percent was achieved between al plant species and almost 100 percent separation was achieved between the crop and weeds. The results show that a combination of spectral imaging and texture analysis may provide a robust method of discrimination with potential for real time application.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Vertical Spreading of Aqueous Trisiloxane Solution Driven by a Spontaneously Developing Surface Tension Gradient (2008)

This article reports the results of experiments conducted on the spontaneous climbing of an aqueous film of trisiloxane surfactants (“superspreaders”) on a vertical strongly hydrophobic solid surface. The final height achieved is much in excess of that expected purely on the basis of the capillary wetting action and suggests that a spontaneously developing surface tension gradient aids in film climbing. Maxima are observed in both the spreading rate and the height achieved as a function of the surfactant concentration, similar to the spreading of a superspreader drop on a horizontal hydrophobic surface.
A quantitative study of the pathways involved in the formation of radiolysis products in ethyl palmitate (1983)

Abstract The various compounds produced by irradiation in ethyl palmitate have been determined by direct mass spectrometry and gas chromatography mass spectrometry. Postulated mechanisms for their formation have been confirmed by a comparison of product yields, and a material balance is shown between the G‐values for products and their putative precursors. The total product yield is seen to be nearly equal to the amount of radiation absorbed. Three new radiolysis products, viz. ethyl α‐ethylpalmitate, ethyl hexadecen‐2‐oate and butyl palmitate are reported.
Parasites, nutrition, immune responses and biology of metabolic tissues (2017)

Nutritional immunology, immunometabolism and identification of novel immunotherapeutic targets are areas of active investigation in parasitology. There is a well-documented crosstalk among immune cells and cells in metabolically active tissues that is important for homeostasis. The numbers and function of these cells are altered by obesity leading to inflammation. A variety of helminths spend some part of their life cycle in the gastrointestinal tract and even entirely enteral nematode infections exert beneficial effects on glucose and lipid metabolism. The foundation of this review is the ability of enteric nematode infections to improve obesity-induced type 2 diabetes and the metabolic syndrome, which are significant health issues in developed areas. It considers the impact of nutrition and specific nutritional deficiencies, which are occur in both undeveloped and developed areas, on the host's ability mount a protective immune response against parasitic nematodes. There are a number of proposed mechanisms by which parasitic nematodes can impact metabolism including effects gastrointestinal hormones, altering epithelial function and changing the number and/or phenotype of immune cells in metabolic tissues. Nematodes can also exert their beneficial effects through Th2 cytokines that activate the transcription factor STAT6, which upregulates genes that regulate glucose and lipid metabolism.
VARIATION IN GROWTH AND ION UPTAKE IN RICE CULTIVARS UNDER NaCl STRESS IN HYDROPONICS (2007)

The study was planned to screen rice genotypes against different levels of salinity. Nursery was sown in sand. At two leaf stage, nursery was shifted to iron tubs floating over Yoshida nutrient solution in wire house-based hydroponics unit at three salinity levels (60 mol m -3 , 100 mol m -3 and 150 mol m -3 ) using CRD factorial arrangement. Phenotypic performance based on survival of tolerant and susceptible genotypes was evaluated after 28 days of salt (NaCl) stress. Results of trial showed that the increase in salinity level decreased the growth of the seedlings of rice genotypes. However, decrease was more pronounced at 150 mol m -3 NaCl concentrations in the growth medium. Genotype KS-282 performed best at all levels of salinity on basis of shoot, root fresh and dry weight basis, respectively. Chemical analysis of shoots using flame photometer showed an increase in Na+ contents and reduction in K+ contents with each increment in salinity, irrespective of rice genotypes. A rapid increase in the K+:Na+ ratio in shoots was mainly the result of a high accumulation of Na + . The genotype KS-282 exhibited a low accumulation of Na + contents and high accumulation of K + contents followed by IR-6 when compared to the other genotypes in saline environment. The physio-chemical analysis indicated that KS-282 was the most tolerant and KS-412 was the most sensitive genotypes. However, the selectivity of K+ over Na+, as exhibited by KS-282 and IR-6, appeared to be an important salt tolerant determinant.
Lymphocyte mechanotransduction: The regulatory role of cytoskeletal dynamics in signaling cascades and effector functions (2019)

The process of mechanotransduction, that is, conversion of physical forces into biochemical signaling cascades, has attracted interest as a potential mechanism for regulating immune cell activation. The cytoskeleton serves a critical role in a variety of lymphocyte functions, from cellular activation, proliferation, adhesion, and migration, to creation of stable immune synapses, and execution of functions such as directed cytotoxicity. Though traditionally considered a scaffold that enables formation of signaling complexes that maintain stable immune synapses, the cytoskeleton was additionally shown to play a dynamic role in lymphocyte signaling cascades by sensing physical cues such as substrate rigidity, and transducing these mechanical features into chemical signals that ultimately influence lymphocyte effector functions. It is thus becoming clear that cytoskeletal dynamics are essential for the lymphocyte response, beyond the role of the cytoskeleton as a stationary framework. Here, we describe the transduction of extracellular forces to activate signaling pathways and effector functions mediated through the cytoskeleton in lymphocytes. We also highlight recent discoveries of cytoskeleton-mediated mechanotransduction on intracellular signaling pathways in NK cells.
Domain walls, domain wall transformations and structural changes in permalloy nanowires when subjected to current pulses (2007)

Abstract We report the direct transmission electron microscopy observation of spin structure transformations in nanoscale Permalloy zigzag wires due to Joule heating during the injection of current pulses. This heating is sufficient to overcome the energy barriers separating the different metastable domain wall spin structures. Due to the large energy barriers these are stable and observable at room temperature by off‐axis electron holography and Fresnel imaging. The interaction between different domain walls is probed and the main pinning mechanism is determined to be the edge roughness. In addition to transformations, we also report on thermally assisted domain wall hopping between two pinning sites and structural changes that occur when the samples are subjected to even higher current pulses. (© 2008 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)
Magnetoresistive characterization of thin-film structures by a gradient-field method (abstract) (1994)

Magnetoresistance measurements can be used during manufacturing to characterize basic magnetic parameters at the device level. A fruitful approach is to take advantage of the gradient field generated by the current flowing through the sample. This method was employed by Smith et al. in an elegant series of experiments that led to precise measurements of exchange constant in soft magnetic thin films. In the present paper, local coupling in bilayers, anisotropy, and interface quality are investigated using magnetoresistive response to gradient fields. Permalloy samples consisting of two sputtered layers (0.1 μm thick) separated by thin SiO2 spacers were patterned in the form of long stripes parallel to the easy axis. Variation in resistance was measured as a function of external field applied in the easy-axis direction and of current density. For similar geometries, the samples have similar resistance. The curves display a sharp decrease in the resistance near zero field that is associated with the reversal of the magnetization in the stripe. Once the sample has switched, coupled layers have a flat response versus field: exchange coupling between the layers constrains the fanning of the magnetization, as previously described. For uncoupled or weakly coupled samples, the curves show curvature at higher fields, and the curvature increases markedly with current density. The fanning within each layer is constrained by exchange, but the average magnetization in one layer rotates under the influence of the field generated by the current in the other layer.
Wireless Integrated Voltametric and Amperometric Biosensing (2006)

Central Nervous System (CNS) uses the interplay between signals of different modalities to transfer and process information. Neurological events are characterized by changes in both neurochemical concentrations and the electrical activity of neurons. Electro physiological and neurochemical events are highly correlated as one causes the other and vice-versa. The ability to simultaneously record electrical and chemical activity is of considerable research and diagnostic importance. Here, we present a hardware implementation for wireless power and clock transfer to and serial transmission of digitized neurochemical and electro physiological data from sensors over one RF link. The idea can be extended to sensors of different modalities having widely different data rates. Neurochemical data are acquired in real-time from a custom multichannel very large scale integrated (VLSI) potentiostat chip at 5 Hz. Field potential data were sampled at 400 Hz. A custom VLSI chip powers up and supplies clocks to the potentiostat and telemeters the multiplexed data. All the chips were fabricated in AMI 3M-2P 0.5μ CMOS process. We demonstrate successful operation of the system with wireless powering and telemetry of the multiplexed data.
An extension of PESQ for assessing the quality of speech degraded by severe time clipping and linear frequency response distortions (2004)

PESQ (ITU-T recommendation P.862) has been establishedas a world standard for assessing speech quality. This paper shows its limitations when it is used for assessing the quality of speech that has been degraded by large amounts of time clipping and linear frequency distortions. A significant improvement in correlation could be obtained without degrading the PESQ performance on other types of distortion.
Dolly (2011)

Cloud computing platforms are becoming increasingly popular for e-commerce applications that can be scaled on-demand in a very cost effective way. Dynamic provisioning is used to autonomously add capacity in multi-tier cloud-based applications that see workload increases. While many solutions exist to provision tiers with little or no state in applications, the database tier remains problematic for dynamic provisioning due to the need to replicate its large disk state. In this paper, we explore virtual machine (VM) cloning techniques to spawn database replicas and address the challenges of provisioning shared-nothing replicated databases in the cloud. We argue that being able to determine state replication time is crucial for provisioning databases and show that VM cloning provides this property. We propose Dolly, a database provisioning system based on VM cloning and cost models to adapt the provisioning policy to the cloud infrastructure specifics and application requirements. We present an implementation of Dolly in a commercial-grade replication middleware and evaluate database provisioning strategies for a TPC-W workload on a private cloud and on Amazon EC2. By being aware of VM-based state replication cost, Dolly can solve the challenge of automated provisioning for replicated databases on cloud platforms.
Ultra‐low‐angle microtomy to back up S‐SIMS molecular depth profiling with C <sub>60</sub> <sup>+</sup> and Bi <sub>n</sub> <sup>+</sup> for the nanoscale analysis of high‐tech industrial materials (2010)

Abstract Polyatomic projectiles such as C 60 + have been used for molecular sputter depth profiling in time‐of‐flight static secondary ion mass spectrometry (ToF‐S‐SIMS). However, the practical application for nanoscale analysis problems still depends on the likely change of secondary ion yield with depth. Therefore, ultra‐low‐angle microtomy (ULAM) has been applied in conjunction with dual beam depth profiling (Bi 3 + C 60 + + + ) on polymer systems relevant to printing industry. Sputter depth profiles have been recorded from two 200 nm poly(methyl methacrylate) (PMMA) layers with additives. Furthermore, also a poly(vinyl pyrrolidone) (PVP)‐PMMA bilayer on Si (thickness of each layer 200 nm) was analyzed using sputter depth profile measurements. Identical samples have been prepared using UV‐cured acrylate as substrate allowing ULAM to be performed. The exposed surfaces have been analyzed using Bi n q+ liquid metal ion gun (LMIG). Use of a cutting angle of 0.3° and 0.1° makes that, in principle, surface analysis off the section with a spot of 150 nm characterises a depth range of 0.3–0.8 nm in the initial sample. The results show that ULAM is a valuable tool to complement the exploratory use of direct sputter depth profiling. To the best of our knowledge, this feasibility study is the first to show the experimental verification of molecular C 60 + sputter depth profiles. Copyright © 2010 John Wiley &amp; Sons, Ltd.
Impact of the cultivation strategy on resveratrol production from glucose in engineered Corynebacterium glutamicum (2017)

The health benefits of polyphenols such as stilbenes and flavonoids for humans are increasingly attracting attention. Resveratrol is a well-characterized naturally-occurring stilbene and potent anti-oxidant, which is used as food supplement and cosmetic ingredient. Several microorganisms including Corynebacterium glutamicum were engineered for resveratrol production from glucose. Based on the cultivation of a resveratrol-producing C. glutamicum strain in shake flasks, different strategies for improving production under controlled conditions at bioreactor scale were tested. To this end, different cultivation parameters including substrate concentration and operation modes (batch and fed-batch) were evaluated. Whereas the highest biomass concentration was observed during fed-batch fermentation, the maximum resveratrol production was achieved in batch mode. The maximal titer obtained was 12mgL<sup>-1</sup> of resveratrol without the addition of the fatty acid synthase inhibitor cerulenin, which was previously shown to be crucial for production with C. glutamicum. The specific growth rate during production seems to have a significant effect in resveratrol production and apparently low specific growth rates may redirect the metabolic bottleneck from p-coumaric acid formation to malonyl-CoA or ATP availability. We also show that high oxygen concentrations in the bioreactor negatively affected the obtained resveratrol titers with C. glutamicum, which is most likely due to the strong tendency of resveratrol to oxidize or oligomerize. Thus, up-scaling of the resveratrol production process is technically challenging and individual process parameters have to be optimized cautiously.
P-D3 Structural determinants for the selective Anti-HIV-1 activity of the all-beta alternative conformer of XCL1 (2016)

We recently reported that the C-chemokine XCL1/lymphotactin is a conformation-dependent broad-spectrum inhibitor of HIV-1 infection, acting at the level of viral entry via an unconventional mechanism that is mediated by direct interaction with the external envelope glycoprotein, gp120. HIV-1 inhibition by XCL1 requires access to the alternative all-beta conformation, which interacts with glycosaminoglycans (GAG) but not with the specific XCL1 receptor, XCR1. To investigate the structural determinants of the HIV-inhibitory function of XCL1, we performed a detailed structure-function analysis of a stabilized all-beta variant, XCL1 W55D. Individual alanine substitutions of two basic residues within the 40s' loop, K42 and R43, abrogated the ability of XCL1 to bind to the viral envelope and block HIV-1 infection; moreover, a loss of HIV-inhibitory function, albeit less marked, was seen upon individual mutation of three additional basic residues, R18, R35 and K46. In contrast, mutation of K42 to arginine did not cause any loss of function, indicating that the interaction with gp120 is primarily electrostatic in nature. Strikingly, four of these five residues cluster to form a large (∼350Å2) positively-charged surface in the all-beta XCL1 conformation, while they are dissociated in the classic chemokine fold, which is inactive against HIV-1, providing a structural basis for the selective antiviral activity of the alternatively-folded XCL1. Furthermore, we observed that changes to the N-terminal domain, which is proximal to the cluster of putative HIV-1 gp120-interacting residues, also affect the antiviral activity of XCL1. Interestingly, the complement of residues involved in HIV-1 blockade is partially overlapping, but distinct from those involved in the GAG-binding function of XCL1. These data identify key structural determinants of anti-HIV activity in XCL1, and may be useful in guiding the rational design of new inhibitors of HIV-1 entry.
The relationship between optimal and biologically plausible decoding of stimulus velocity in the retina (2009)

A major open problem in systems neuroscience is to understand the relationship between behavior and the detailed spiking properties of neural populations. We assess how faithfully velocity information can be decoded from a population of spiking model retinal neurons whose spatiotemporal receptive fields and ensemble spike train dynamics are closely matched to real data. We describe how to compute the optimal Bayesian estimate of image velocity given the population spike train response and show that, in the case of global translation of an image with known intensity profile, on average the spike train ensemble signals speed with a fractional standard deviation of about 2% across a specific set of stimulus conditions. We further show how to compute the Bayesian velocity estimate in the case where we only have some a priori information about the (naturalistic) spatial correlation structure of the image but do not know the image explicitly. As expected, the performance of the Bayesian decoder is shown to be less accurate with decreasing prior image information. There turns out to be a close mathematical connection between a biologically plausible "motion energy" method for decoding the velocity and the Bayesian decoder in the case that the image is not known. Simulations using the motion energy method and the Bayesian decoder with unknown image reveal that they result in fractional standard deviations of 10% and 6%, respectively, across the same set of stimulus conditions. Estimation performance is rather insensitive to the details of the precise receptive field location, correlated activity between cells, and spike timing.
3D phase-shifting fringe projection system on the basis of a tailored free-form mirror (2013)

Phase-shifting fringe projection is an effective method to perform 3D shape measurements. Conventionally, fringe projection systems utilize a digital projector that images fringes into the measurement plane. The performance of such systems is limited to the visible spectral range, as most projectors experience technical limitations in UV or IR spectral ranges. However, for certain applications these spectral ranges are of special interest. We present a wideband fringe projector that has been developed on the basis of a picture generating beamshaping mirror. This mirror generates a sinusoidal fringe pattern in the measurement plane without any additional optical elements. Phase shifting is realized without any mechanical movement by a multichip LED. As the system is based on a single mirror, it is wavelength-independent in a wide spectral range and therefore applicable in UV and IR spectral ranges. We present the design and a realized setup of this fringe projection system and the characterization of the generated intensity distribution. Experimental results of 3D shape measurements are presented.
Finite-difference Solutions of Electromagnetic Wave Propagation in Conducting Media (1995)

Time-domain electromagnetic methods in geophysics include the relatively low frequency transient (TEM) and ground-penetrating radar methods. Problems of time-dependent electromagnetic wave propagation are generally not yet solvable for complex media. Mostly, these problems have been treated theoretically through frequency-domain approaches.
A Comparison of Evaluation Metrics for a Broad-Coverage Stochastic Parser (2003)

This paper reports on the use of two distinct evaluation metrics for assessing a stochastic parsing model consisting of a broad-coverage Lexical-Functional Grammar (LFG), an efficient constraint-based parser and a stochastic disambiguation model. The first evaluation metric measures matches of predicate-argument relations in LFG f-structures (henceforth the LFG annotation scheme) to a gold standard of manually annotated f-structures for a subset of the UPenn Wall Street Journal treebank. The other metric maps predicate-argument relations in LFG f-structures to dependency relations (henceforth DR annotations) as proposed by Carroll et al. (Carroll et al., 1999). For evaluation, these relations are matched against Carroll et al.&amp;apos;s gold standard which was manually annnotated on a subset of the Brown corpus. The parser plus stochastic disambiguator gives an F-measure of 79% (LFG) or 73% (DR) on the WSJ test set. This shows that the two evaluation schemes are similar in spirit, although accuracy is impaired systematically by mapping one annotation scheme to the other. A systematic loss of accuracy is incurred also by corpus variation: Training the stochastic disambiguation model on WSJ data and testing on Carroll et al.&amp;apos;s Brown corpus data yields an F-score of 74% (DR) for dependency-relation match. A variant of this measure comparable to the measure reported by Carroll et al. yields an F-measure of 76%. We examine divergences between annotation schemes aiming at a future improvement of methods for assessing parser quality.