cssi/SciSciGPT-SciSciNet huggingface dataset:
Dynamic pressure gradient modulation for comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry detection

Abstract Dynamic pressure gradient modulation (DPGM) is investigated for comprehensive two-dimensional gas chromatography (GC × GC) with time-of-flight mass spectrometry (TOFMS) detection. With DPGM, a commercial pneumatic “pulse” valve is opened to introduce a suitably high auxiliary gas pressure at a T-junction connecting the first dimension (1D) and second dimension (2D) columns during the modulation period (PM), temporarily stopping the 1D flow. The valve is then closed for the duration of a pulse width (pw) to “re-inject” temporally focused 1D eluate onto the 2D column for separation. This flow modulation technique is observed to be compatible with TOFMS detection using a 2D flow rate of 4 ml/min for the separation of a 90-component test mixture. A 25 min separation window using a PM = 1 s and pw = 200 ms for full modulation (and 100% duty cycle) provided an average 1Wb = 4.5 s and 2Wb = 130 ms for a 2D peak capacity of nc,2D = 2700 (100 peaks per min). The detector response enhancement factor (DREF) serves as a metric for the enhanced sensitivity of the modulated relative to the unmodulated 1D peaks, with DREFs ranging between 10 and 20 and about a 5-fold improvement in signal-to-noise ratio (S/N). The bilinear “quality” of the GC × GC data is studied using the chemometric method parallel factor analysis (PARAFAC). Since PARAFAC requires sufficiently trilinear data, the reproducibility of the 2D peak shape for a given analyte is confirmed using lack-of-fit (LOF) and percent variation (R2) metrics. The limit-of-detection (LOD) for the representative analyte hexadecane is determined using PARAFAC, providing an LOD of 0.7 ppb (±0.03 ppb) for three replicates. Seven heavily overlapped analytes are also fully resolved by PARAFAC down to the part-per-million (ppm) concentration level, producing reproducible spectra with a majority of spectral match values (MV) over 800 (RSD ≤ 7.1%). This study provides promising results for DPGM as a flow modulation technique compatible with GC × GC-TOFMS, providing high sensitivity data suitable for chemometric analysis.
Giant omphalocele closure utilizing botulinum toxin

Abstract An omphalocele is a rare congenital abdominal wall defect of the umbilical ring. A giant omphalocele is typically defined as 5 cm or larger. Here we present a case of utilizing botulinum toxin to aid in closure of a giant omphalocele. Lack of abdominal domain prevented visceral reduction and initial treatment involved and alloderm silo and wound vac dressing allowing granulation tissue epithelialization. Patient underwent two rounds of botox injections and fascial closure was obtained. Chemical component separation with botox injection of the abdominal wall musculature is safe and effective for augmenting closure of giant omphalocele.
Professional Development to Support Teachers’ Implementation of Intensive Reading Intervention: A Systematic Review

Many educators are unprepared to meet the needs of students with the most intensive reading intervention needs. The purpose of this review was to identify how researchers have provided professional...
Stable membrane candidate for deployable membrane space telescopes

Larger mirrors are needed to satisfy the requirements of the next generation of UV–Vis space telescopes. Our study attempts to meet this requirement by demonstrating a technology that would deploy a large, continuous, high figure accuracy membrane mirror. The figure of the membrane mirror is corrected after deployment using a contiguous coating of a magnetic smart material (MSM) and a magnetic field. The MSM is a magnetostrictive material that is operable by magnetic write head(s), locally imposed on the nonreflective side of the membrane mirror. We report preparation, figure accuracy, stress analysis, and stability of the MSM coated CP1 polyimide substrate membrane mirror. The figure accuracy and magnetostrictive performance of the MSM coated membrane mirror are measured; furthermore, stability of the CP1 membrane for 48 h is observed and the results are found to be promising. In addition to membrane coating and the experimental procedure, the results of the surface profiling experiments are introduced and discussed.
Abstract 5443: Modulating plasticity in aggressive variant prostate cancers

Aggressive Variant Prostate Cancers (AVPC) are a clinically and molecularly distinct subset of prostate cancers with a poor prognosis characterized by androgen-indifference, platinum-sensitivity and combined defects in Tp53, RB1 and PTEN, for which novel therapeutic approaches are urgently needed. Defects observed in these tumor suppressor pathways have been linked to lineage plasticity in genetically engineered mouse models. We hypothesized that this plasticity can be identified in human tumor samples, and can be modulated to serve as the foundation for effective combination therapies for the AVPC subset. We previously defined a gene expression signature derived from mouse embryonic day 6.5 that is representative of extensive cellular plasticity (PMID:26123483). We determined the plasticity scores in 12 patient-derived xenograft (PDX) models representative of the spectrum of prostate cancer biology (using available RNA sequencing profiles), and in 26 macrodissected tumor biopsies obtained from patients who received platinum-based chemotherapy for aggressive prostate cancer (using ALMAC Affymetrix gene expression microarray). As expected, the AVPC PDX models exhibited high plasticity scores as did 11 (42.3%) of the patient samples, associated with patient progression free- and overall survival. We next treated a well characterized AVPC PDX model (144-4) with the anti-EMT drug (p38MAPK inhibitor) SB203580 at 10mg/kg, and observed a decrease in stem-cell and EMT factors associated with plasticity. These data confirm the association between plasticity and AVPC in human tumor samples, and suggest that changes in plasticity can be measured in tumor samples to determine the value of its modulation in clinical trials. Acknowledgments: ALMAC Diagnostics Services, UK, and UTMDACC ATGC Core Lab (CCSG-CA016672-ATGC) for RNA sequencing services; UTMDACC Prostate Cancer SPORE (RS, SAM, AA), UTMDACC IRG (RS), and the UTMDACC Prostate Cancer Moonshot Program (AA) for financial support. Citation Format: Rama Soundararajan, Petra den Hollander, Peter Shepherd, Nora Navone, Daniele Lorenzini, Caddie Laberiano-Fernandez, Wei Lu, Jianling Zhou, Jingjing Liu, Jianhua Zhang, Luisa Maren Solis-Soto, Sendurai A. Mani, Ana Aparicio. Modulating plasticity in aggressive variant prostate cancers [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5443.
LED-based Solar Ring Light Simulator on a Measurescope

Luminance and irradiance uniform ring-light is essential for image processing and machine vision for measure scopes. A curved lens is designed for irradiance uniformity and five types of wavelengths of LEDs are used to fulfill luminance uniformity.
Experimental demonstration of tethered gene drive systems for confined population modification or suppression

Homing gene drives hold great promise for the genetic control of natural populations. However, current homing systems are capable of spreading uncontrollably between populations connected by even marginal levels of migration. This could represent a substantial sociopolitical barrier to the testing or deployment of such drives and may generally be undesirable when the objective is only local population control, such as suppression of an invasive species outside of its native range. Tethered drive systems, in which a locally confined gene drive provides the CRISPR nuclease needed for a homing drive, could provide a solution to this problem, offering the power of a homing drive and confinement of the supporting drive. Here, we demonstrate the engineering of a tethered drive system in Drosophila, using a TARE drive to support modification and suppression homing drives. Each drive was able to bias inheritance in its favor, and the TARE drive was shown to spread only when released above a threshold frequency in experimental cage populations. After the TARE drive had established in the population, it facilitated the spread of a subsequently released split homing modification drive (to all individuals in the cage) and of a homing suppression drive (to its equilibrium frequency). Our results show that the tethered drive strategy is a viable and easily engineered option for providing confinement of homing drives to target populations.
Epithelial Immunomodulation by Aerosolized Toll like Receptor Agonists Attenuate Allergic Responsiveness in Mice

Abstract Allergic asthma is a chronic inflammatory respiratory disease associated with eosinophilic infiltration, increased mucus production, airway hyperresponsiveness (AHR), and airway remodeling. Epidemiologic data has revealed that the prevalence of allergic sensitization and associated diseases has increased in the twentieth century. This has been hypothesized to be partly due to reduced contact with microbial organisms (the hygiene hypothesis) in industrialized society. Airway epithelial cells, once considered a static physical barrier between the body and the external world, are now widely recognized as immunologically active cells that can initiate, maintain, and restrain inflammatory responses, such as those that mediate allergic disease. Airway epithelial cells can sense allergens via myriad expression of Toll-like receptors (TLRs) and other pattern-recognition receptors (PRRs). We sought to determine whether the innate immune response stimulated by a combination of Pam2CSK4 (“Pam2”, TLR2/6 ligand) and a class C oligodeoxynucleotide ODN362 (“ODN”, TLR9 ligand) when delivered together by aerosol (“Pam2ODN”), can modulate the allergic immune response to allergens. Treatment with Pam2ODN 7 days before sensitization to House Dust Mite (HDM) extract resulted in a strong reduction in eosinophilic and lymphocytic inflammation. This Pam2ODN immunomodulatory effect was also seen using Ovalbumin (OVA) and A. oryzae (Ao) mouse models. The immunomodulatory effect was observed as much as 30 days before sensitization to HDM, but ineffective just 2 days after sensitization, suggesting that Pam2ODN immunomodulation lowers the allergic responsiveness of airway epithelial cells. Furthermore, Pam2 and ODN cooperated synergistically suggesting that this treatment is superior to any single agonist in the setting of allergen immunotherapy. One Sentence Summary A synergistic combination of Toll-like Receptor agonists, delivered directly into the lung mucosa, can attenuate allergic responsiveness of airway epithelial cells and prevent host sensitization to aeroallergens. What is already known Allergic sensitization has increased in the 20th century due to reduced contact with microbial organisms in industrialized society (ie. hygiene hypothesis) We have previously identified a pharmacological means to stimulate innate immunity of lung epithelial cells. What this study adds Activation of innate immunity in lung epithelial cells attenuates the allergic responsiveness of mice. Synergistic cooperation of pattern recognition receptors induces stronger immunomodulatory responses What is the clinical significance Aerosolized Toll-like Receptor agonists have been demonstrated as safe in human clinical trials This study provides proof-of-principle that aerosolized toll-like receptor agonists could have clinical efficacy in the setting of the allergen immunotherapy
Intellectual Property, Cultural Heritage and Human Rights

The relationship between intellectual property and human rights in the cultural heritage context is both complex and challenging. Although these two sets of rights frequently align, they also compete against each other. The resulting tensions and conflicts affect not only the relevant cultural groups but all of us. Even more challenging, there has so far been no consensus on how to protect cultural heritage. Nor are there generally agreed definitions of "culture" and "cultural heritage." Although a diverse array of conventions, protocols, declarations, laws, policies and guidelines has been established to protect cultural heritage and cultural diversity, many of these normative documents include definitions that were drafted on a text-by-text basis. It is therefore difficult to generalize definitions across a variety of contexts, including those at the intersection of intellectual property and human rights. This chapter begins by mapping the contours of the international human rights framework at it relates to intellectual property and cultural heritage. The chapter then offers three sets of illustrations covering situations in which tensions and conflicts between human rights and intellectual property rights may arise: (1) the production of user-generated content; (2) the reproduction of indigenous cultural heritage; and (3) the digitization, sharing or dissemination of cultural materials by museums, libraries and archives. This chapter concludes by advancing a three-step balancing process to help resolve these potential tensions and conflicts.
Wittgenstein, Frazer and Religion

It is now almost platitudinous to state that there is a profound reli­gious dimension to the work of Ludwig Wittgenstein. Nevertheless, this attribution of a religious quality may seem bizarre when one is confronted with his two masterpieces — Tractatus Logico-Philosophicus and Philosophical Investigations — which seem to have little application to life, let alone to affairs of the spirit. Yet Wittgenstein’s work became associated with religion when sympathetic philosophers applied his notions of ‘language-games’ and ‘forms of life’ to religious belief and practice. Closer attention to Wittgenstein’s philosophy (and how he perceived it) then revealed that much of his writing was conditioned by religious considerations. For instance, his correspondence with Paul Engelmann and Ludwig von Ficker regarding the contents of the Tractatus reveal his conviction that ‘the point of the book is ethical’ (Wittgenstein 1979a: 94). And there is good reason to think that he regarded his other works as such: for example, the foreword to the Philosophical Remarks states ‘This book is written to the glory of God’ (Wittgenstein 1975: 7).
Fast random rotation matrices

Publisher Summary This chapter describes a method for generation of uniformly distributed random rotations of a unit sphere and illustrates an efficient procedure for creating random 3 × 3 rotation matrices. The chapter describes a complete algorithm, combining the reflection and simple rotation. The procedure of random rotation requires three uniformly distributed random numbers between 0 and 1. If the three random numbers are obtained by stratified or jittered sampling of the unit cube, the resulting rotation matrices will inherit the benefit of, less clumping. If the range of the random input variables is restricted, then uniformly distributed perturbations or wobbles within given limits can be generated. The chapter presents the result of applying 1,000 random rotations to a sphere with an arrow painted at one pole. The resulting pattern looks much the same from any vantage point, providing visual confirmation of uniformity.
Rebecca Dickinson: Independence for a New England Woman

Rebecca Dickinson: Independence for a New England Woman takes a microhistorical approach in its exploration of 1738–1815 New England. Marla R. Miller, who teaches at the University of Massachusetts...
Reshaping the 2D MPI PSF to be isotropic and sharp using vector acquisition and equalization

Magnetic particle imaging (MPI) is a promising imaging technique for a variety of clinical and scientific applications ranging from angiography [1] to stem cell tracking [2]. The native 2D point spread function (PSF) presents two challenges: the PSF is anisotropic, and there is an obscuring image “haze” that reduces image contrast due to the long tails of the 2D PSF [3]. These effects are illustrated in Fig. 1 (b), (c)). Full deconvolution can improve spatial resolution and anisotropy, but the cost in SNR can be objectionable [4-5]. Here, we show that performing k-space equalization and vector acquisition [6] can address both of these challenges with minimal loss of SNR and a significant increase in CNR.
Residual feed intake is repeatable for lactating Holstein dairy cows fed high and low starch diets.

Abstract Residual feed intake (RFI) is a tool to quantify feed efficiency in livestock and is commonly used to assess feed efficiency independent of production level, body weight (BW), or BW change. Lactating Holstein cows (n=109; 44 primiparous and 65 multiparous), averaging (mean ± standard deviation, SD) 665±77kg of BW, 42±9kg of milk/d, and 120±30 d postpartum, were fed diets of high (HI) or low (LO) starch content in 4 crossover experiments with two 28-d treatment periods. The LO diets were ~40% neutral detergent fiber (NDF) and ~14% starch and the HI diets were ~26% NDF and ~30% starch. Individual dry matter intake (DMI) of a cow was modeled as a function of milk energy output, metabolic BW, body energy change, and fixed effects of parity, experiment, cohort nested within experiment, and diet nested within cohort and experiment; RFI for each cow was the residual error term. Cows were classified as high (>0.5 SD of the mean), medium (±0.5 SD of the mean), or low (
Localization Errors in MR Spectroscopic Imaging due to the Drift of the Main Magnetic Field and their Correction

Purpose: To analyze the effect of B0 field drift on multivoxel MR spectroscopic imaging and to propose an approach for its correction. Theory and Methods: It is shown, both theoretically and in a phantom, that for ∼30 min acquisitions a linear B0 drift (∼0.1 ppm/h) will cause localization errors that can reach several voxels (centimeters) in the slower varying phase encoding directions. An efficient and unbiased estimator is proposed for tracking the drift by interleaving short (∼ ), nonlocalized acquisitions on the nonsuppressed water each pulse repetition time, as shown in 10 volunteers at 1.5 and 3 T. Results: The drift is shown to be predominantly linear in both the phantom and volunteers at both fields. The localization errors are observed and quantified in both phantom and volunteers. The unbiased estimator is shown to reliably track the instantaneous frequency in vivo despite only using a small portion of the FID. Conclusion: Contrary to single-voxel MR spectroscopy, where it leads to line broadening, field drift can lead to localization errors in the longer chemical shift imaging experiments. Fortunately, this drift can be obtained at a negligible cost to sequence timing, and corrected for in post processing. Magn Reson Med, 70:895–904, 2013. © 2012 Wiley Periodicals, Inc.
Liposarcoma of the anterior mediastinum and thymus. A clinicopathologic study of 28 cases.

We studied 28 cases of anterior mediastinal liposarcoma occurring in 16 males and 12 females with a mean age of 43 years (range, 14-72). Presenting symptoms included dyspnea (four cases) and chest pain (four cases), although 11 tumors were detected incidentally by routine chest radiography. Seven cases were believed to be located within the thymus. Most (i.e., 25) of the cases were of low grade, with the well-differentiated lipoma-like or sclerosing subtypes constituting 60% and the myxoid subtype constituting 28%; the remaining 12% exhibited mixed features. Three cases were pleomorphic type. Several low-grade tumors exhibited widespread, dense aggregates of mature-appearing lymphocytes and plasma cells, which occasionally obscured the mesenchymal nature of the neoplasm, suggesting instead a lymphoid neoplasm or a reactive fibroinflammatory condition. The three high-grade tumors showed combinations of pleomorphic and round cell patterns, with focal myxoid areas. Of the cases grossly arising within the thymus, only one showed extensive thymic tissue within the lesion ("thymoliposarcoma"); six others exhibited residual thymus peripheral to the tumor. Clinical follow-up in 23 cases revealed recurrence in seven patients (31.8%), with a mean interval to recurrence of 3 years. Eight patients died (mean survival, 2.6 years), one postoperatively and three following a recurrence. Fifteen patients were alive (mean survival, 2 years), four with recurrent tumor. The myxoid tumors had a somewhat more aggressive course than the well-differentiated tumors. Metastases were not observed in any of the patients.
Head waving in Aplysia californica. II. Functional anatomy and muscular activity during behaviour.

Bending and twisting movements of the body during head-waving behaviour of the sea hare Aplysia californica are produced by the concerted action of the muscles of the body wall on the hydrostatic skeleton formed by the haemocoel and internal organs. In this study, we describe the orientations and possible mechanical actions of muscles in the body wall. We also describe the spatial and temporal patterns of longitudinal muscle activity during different head-waving movements in a freely moving animal. The body-wall muscles are arranged as a network of longitudinal, circular and left- and right-handed helical muscle fascicles. Each fascicle consists of a few to several hundred muscle fibres enclosed in a connective tissue sheath. The sheath also connects muscle fascicles of different orientations at the points where they cross, forming a tightly connected network. In addition, a series of large longitudinal muscle fascicles, including the lateral columellar muscles, lies against the inside wall of the dorsal hemicylinder of the animal. In animals with hydrostatic skeletons, longitudinal and circular muscles are necessary for producing all basic elongation, shortening and bending movements, and in Aplysia, the extensive distribution of helical muscles provides the animal with the ability to twist its body about the longitudinal axis, as is observed during horizontal head-waving movements. Muscle activity in the lateral muscles is antiphasically coordinated during horizontal bends, and when the animal is bent to one side, movement towards the centre is accompanied by muscle activity on the side of shortening, i.e. there is no passive return to centre. The muscles near the holdfast are the most active during head-waving movements, with relatively little activity in the head region. The activity of dorsal muscles corresponds to both the existing vertical posture of the body and to discrete dorsal bending movements. In most cases, depression of the head is passive, i.e. both dorsal and ventral longitudinal muscles relax, although foot muscles may also be involved. These observations, together with the constancy of the hydrostatic pressure in the haemocoel during all movements in animals attached to the substratum, suggest specific patterns of motor neurone coordination during different movements.
Variation with Temperature of the Electrification Produced in Air by the Disruption of Water Drops and Its Bearing on the Prevalence of Lightning

The total charge carried by the negative ions which are produced in the air when a water drop is disrupted by falling through a horizontal stream of air was measured for different stream velocities at temperatures between 1\ifmmode^\circ\else\textdegree\fi{}C and 63\ifmmode^\circ\else\textdegree\fi{}C. The dependence of this charge upon the size of the drop was found from observations made with drops differing in volume between 0.076 cc and 0.092 cc. For blasts exceeding that necessary just to disrupt the drops, the charge obtained per drop disrupted increases rapidly both with the velocity of the blast and with increase of temperature. The rate at which the charge changes with increase of temperature of the drop depends upon the magnitude of the air stream employed for producing the disruption. For drops of 5.8 mm diameter falling from a height of 2 cm through a horizontal cylindrical stream of 1 cm diameter and having an average velocity of 20 m/sec., the relation between the numbers of negative ions produced per drop disrupted at the temperatures 1.3\ifmmode^\circ\else\textdegree\fi{}C, 24.2\ifmmode^\circ\else\textdegree\fi{}C, 42.1\ifmmode^\circ\else\textdegree\fi{}C and 62.5\ifmmode^\circ\else\textdegree\fi{}C, respectively, was found to be 1: 3: 6.4: 11. In the range of temperatures found in the atmosphere at different times the amount of electrification produced in the air when raindrops are disrupted by air currents of a given magnitude may be at least three times as large when the rain-water is warm as when it is cold. Rain temperature is therefore an important factor in determining the frequency and the intensity of lightning discharges.
Synergy of Irofulven in combination with various anti-metabolites, enzyme inhibitors, and miscellaneous agents in MV522 lung carcinoma cells: marked interaction with gemcitabine and 5-fluorouracil

The novel agent Irofulven (HMAF, NSC 683863) has demonstrated significant antitumor activity against solid tumors in various xenograft models and human clinical trials. The antitumor potential of combining irofulven with 72 different anti-metabolite, enzyme inhibiting, and miscellaneous agents was investigated in this study. The human lung carcinoma MV522 cell line and its corresponding xenograft model were used to evaluate the activity of irofulven in combination with these different agents. Irofulven in combination with select anti-metabolites, notably cytidine or adenine-derived agents, displayed strong synergistic activity in both in vitro and in vivo studies. Agents demonstrating strong synergistic interaction with irofulven included gemcitabine, cyclocytidine, cytarabine, fludarabine phosphate, cladribine, and 5-fluorouracil. Other anti-metabolites, enzyme inhibitors, and a variety of miscellaneous agents failed to interact beneficially when administered in combination with irofulven. The therapeutic activity of irofulven is enhanced considerably when irofulven is combined with select anti-metabolite agents, and further clinical evaluation of these combinations is warranted. The synergistic interaction with these combinations may stem from a variety of actions including inhibition of the nucleotide excision repair (NER) pathway, topoisomerase I activity, and caspase-dependent and independent induction of apoptosis.
A comparison of multicontinuum theory based failure simulation with experimental results

Abstract This paper is part of a broader exercise to determine the predictive capability of several currently accepted composite failure criteria. Blind failure and stress–strain predictions were originally submitted by us to the organizers of the exercise for 14 different cases involving four different composite materials. A finite element based analysis was used to simulate progressive failure of the various composite laminates under uniaxial and multiaxial loading. Under the assumption of the composite acting as a multicontinuum, fiber and matrix constituent stress and strain states were derived. This information formed the input to a quadratic, stress-interactive constituent-based failure criteria to predict damage at the composite level. Two-dimensional failure envelopes and stress–strain curves for the composite were developed. In what follows, the experimental results have been made available to us for comparison against our analytical failure simulations. Generally, these analytical predictions were in good agreement with experimental results. The presence of simultaneous normal and shear stresses in a composite laminate was found to significantly enhance shear strength which was not accounted for in the proposed failure criteria.
Impact of subtle gaze direction on short-term spatial information recall

Contents of Visual Short-Term Memory depend highly on viewer attention. It is possible to influence where attention is allocated using a technique called Subtle Gaze Direction (SGD). SGD combines eye tracking with subtle image-space modulations to guide viewer gaze about a scene. Modulations are terminated before the viewer can scrutinize them with high acuity foveal vision. This approach is preferred to overt techniques that require permanent alterations to images to highlight areas of interest. In our study, participants were asked to recall the location of objects or regions in images. We investigated if using SGD to guide attention to these regions would improve recall. Results showed that the influence of SGD significantly improved accuracy of target count and spatial location recall. This has implications for a wide range of applications including spatial learning in virtual environments as well as image search applications, virtual training and perceptually based rendering.
Catheter Ablation of Canine Myocardium with Radiofrequency Energy

High energy direct-current shocks delivered via an electrode catheter have been used to ablate the atrioventricular junction since 1981. This technique has also been adapted for ablation of other cardiac tissues including the atrium, posterior interatrial septum and ventricular myocardium. The limitations of this technique include inadequate control of the energy source, poor understanding of the mechanisms of myocardial injury, and untoward complications possibly related to barotraumatic injury. Radiofrequency energy has been shown to create ablative injury when delivered to the myocardium via standard electrode catheters. This report will review our experience with radiofrequency catheter ablation of the canine myocardium with specific emphasis on the biophysical aspects of lesion formation.
Effect of potassium upon the magnesium status of the corn plant

Abstract The relationship between soil K, fertilizer K, plant K, and plant Mg was investigated at three sample periods. A statistically significant linear correlation between variables vas observed. Simple correlations between soil K vs plant K and fertilizer K vs plant K were positive, and simple correlations between soil K vs plant Mg, fertilizer K vs plant Mg, and plant K vs plant Mg were negative in all sample periods. It was shown that there is a possibility that Mg may be limiting corn yields when plant K is at the critical percentage derived under the conditions of this experiment.
High-performance scalable molecular dynamics simulations of a polarizable force field based on classical Drude oscillators in NAMD.

Incorporating the influence of induced polarization in large-scale atomistic molecular dynamics (MD) simulations is a critical challenge in the progress toward computations of increased accuracy. One computationally efficient treatment is based on the classical Drude oscillator in which an auxiliary charged particle is attached by a spring to each nucleus. Here, we report the first implementation of this model in the program NAMD. An extended Lagrangian dynamics with a dual-Langevin thermostat scheme applied to the Drude−nucleus pairs is employed to efficiently generate classical dynamic propagation near the self-consistent field limit. Large-scale MD simulations based on the Drude polarizable force field scale very well on massively distributed supercomputing platforms, the computational demand increasing by only a factor of 1.2 to 1.8 compared to nonpolarizable models. As an illustration, a large-scale 150 mM NaCl aqueous salt solution is simulated, and the calculated ionic conductivity is shown to be i...
An efficient algorithm for solving constrained nonlinear programming problems

Abstract This paper discusses the basis for an efficient technique which transforms a general constrained nonlinear programming problem to a single unconstrained problem. The theoretical considerations are first presented. This is followed by a development of the algorithm. Lastly, an illustrated example is given to demonstrate the methodology.
Circular and near-circular polarization states of evanescent monochromatic light fields in total internal reflection.

Conditions for the production of near-circular polarization states of the evanescent field present in the rarer medium in total internal reflection of incident monochromatic p-polarized light at a dielectric–dielectric planar interface are determined. Such conditions are satisfied if high-index (>3.2) transparent prism materials (e.g., GaP and Ge) are used at angles of incidence well above the critical angle but sufficiently below grazing incidence. Furthermore, elliptical polarization of incident light with nonzero p and s components can be tailored to cause circular polarization of the resultant tangential electric field in the plane of the interface or circular polarization of the transverse electric field in a plane normal to the direction of propagation of the evanescent wave. Such polarization control of the evanescent field is significant, e.g., in the fluorescent excitation of molecules adsorbed at solid–liquid and solid–gas interfaces by total internal reflection.
Ricochet: lateral error correction for time-critical multicast

Ricochet is a low-latency reliable multicast protocol designed for time-critical clustered applications. It uses IP Multicast to transmit data and recovers from packet loss in end-hosts using Lateral Error Correction (LEC), a novel repair mechanism in which XORs are exchanged between receivers and combined across overlapping groups. In datacenters and clusters, application needs frequently dictate large numbers of fine-grained overlapping multicast groups. Existing multicast reliability schemes scale poorly in such settings, providing latency of packet recovery that depends inversely on the data rate within a single group: the lower the data rate, the longer it takes to recover lost packets. LEC is insensitive to the rate of data in any one group and allows each node to split its bandwidth between hundreds to thousands of fine-grained multicast groups without sacrificing timely packet recovery. As a result, Ricochet provides developers with a scalable, reliable and fast multicast primitive to layer under high-level abstractions such as publish-subscribe, group communication and replicated service/object infrastructures. We evaluate Ricochet on a 64-node cluster with up to 1024 groups per node: under various loss rates, it recovers almost all packets using LEC in tens of milliseconds and the remainder with reactive traffic within 200 milliseconds.
Large displacement analysis of viscoelastic shells of revolution

Abstract The incremental equilibrium equations for a body subjected to large deformations are given in a Lagrangian description. The loading terms due to both conservative and nonconservative types of loading are derived using virtual work considerations. The simple integral constitutive laws of the infinitesimal theory of linear viscoelasticity are generalized to small strain, large rotation applications through the use of invariant strain and stress measures. The viscoelastic material is characterized using a Prony series expansion for the relaxation modulus, leading to a simple algorithm for the evaluation of the convolution integrals. The shell geometry and displacement fields are discretized by the “degenerate” isoparametric shell element. The numerical examples include the post-buckling behavior of an elastic shallow spherical shell and the viscoelastic creep buckling of a spherical cap subjected to sustained loading.
Coherent Backscattering in the Cross-Polarized Channel

We analyze the asymptotic behavior of the cross-polarized enhancement factor in the framework of the standard low-packing-density theory of coherent backscattering by discrete random media composed of spherically symmetric particles. It is shown that if the particles are strongly absorbing or if the smallest optical dimension of the particulate medium (i.e., the optical thickness of a plane-parallel slab or the optical diameter of a spherically symmetric volume) approaches zero, then the cross-polarized enhancement factor tends to its upper-limit value 2. This theoretical prediction is illustrated using direct computer solutions of the Maxwell equations for spherical volumes of discrete random medium.
A review of North Atlantic modes of natural variability and their driving mechanisms

[1] This paper reviews three modes of natural variability that have been identified in the North Atlantic Ocean, namely, the North Atlantic Oscillation (NAO), the Atlantic Multidecadal Oscillation (AMO) and the Atlantic Meridional Mode (AMM). This manuscript focuses on the multidecadal fluctuations of these three modes. A range of different mechanisms to initiate phase reversals in these modes on multidecadal timescales has been suggested previously. We propose a systematic grouping of these mechanisms into three types that involve, respectively, (1) the dependency of the Atlantic thermohaline circulation (THC) on salinity, (2) the sensitivity of the THC to changes in ocean heat transport and (3) the dependency of the NAO to changes in the Atlantic meridional temperature gradient. Some new density data is also provided, demonstrating physical links between the THC and the AMO.
The A to Z of SoCs

The exploding complexity of new chips and the ever decreasing time-to-market window are forcing fundamental changes in the way systems are designed. The advent of Systems-on-Chip (SoC) based on pre-designed intellectual-property (IP) cores has become an absolute necessity for embedded systems companies to remain competitive. Designing an SoC, however, is extremely complex, as it encompasses a range of difficult problems in hardware and software design. This paper explains a wide range of SoC issues including market drivers and trends, technology and integration aspects, early architecture definition, methodology, hardware and software design and verification techniques.
Auditory temporal discrimination by trained listeners

Abstract Previous reports from this laboratory have shown that untrained listeners cannot name the order of sounds in extended sequences of unrelated items such as hisses, tones, and buzzes at item durations of 200 msec, even though identification of order for the sounds of speech and music is accomplished readily at much shorter item durations. The present study indicates that under appropriate conditions subjects can be trained to distinguish between and to identify permuted orders within sequences of nonrelated sounds each lasting only 10 msec or less. Evidence is presented suggesting that much of what passes for direct identification of order is actually based on prior identification of a larger pattern. Two principal mechanisms seem to mediate discrimination of auditory temporal order: (1) fine resolution (requiring prior training) permitting identification of over-all patterns and capable of operating with item durations of only a few msec; (2) coarse resolution (special prior training not required) allowing naming of order of items having minimal durations usually above 200 msec for unfamiliar sequences.
Eye and head movements in patients with achromatopsia

The diagnosis of patients with rod monochromatism (RM) and blue-cone monochromatism (BCM) may be difficult. The relative direction and symmetry of nystagmus of the two eyes, as well as the existence or nature of rhythmic head movements, are not known. We analyzed simultaneous eye and head movement recordings of 16 patients with RM and three patients with BCM. Longitudinal examinations were performed in seven patients. Younger patients had pendular, intermittent or continuous oblique nystagmus with both eyes oscillating in phase or out of phase with equal amplitudes. Older patients had continuous symmetrical oblique jerk nystagmus with decreasing velocities in the slow phase. In two children, we demonstrated evolution from pendular to predominantly jerk nystagmus. Rhythmic head movements were detected in all children. Patients with RM and BCM exhibit a distinct entity of nystagmus and can be differentiated from patients with congenital or latent nystagmus. However, eye and head movements can mimic spasmus nutans.
Factors Affecting Rheological Characteristics of Fibril Gels: The Case of β-Lactoglobulin and α-Lactalbumin

Some of the factors that affect the rheological characteristics of fibril gels are discussed. Fibrils with nanoscale diameters from beta-lactoglobulin (beta-lg) and alpha-lactalbumin (alpha-la) have been used to create gels with different rheological characteristics. Values of the gelation time, t(c), the critical gel concentration, c(0), and the equilibrium value of the storage modulus, G, such as at long gelation times, derived from experimental rheological data, are discussed. Fibrils created from beta-lg using solvent incubation and heating result in gels with different rheological properties, probably because of different microstructures and fibril densities. Partial hydrolysis of alpha-la with a serine proteinase from Bacillus licheniformis results in fibrils that are tubes about 20 nm in diameter. Such a fibril gel from a 10% (w/v) alpha-la solution has a higher modulus than a heat-set gel from a 10% (w/w) beta-lg, pH 2.5 solution; it is suggested that one reason for the higher modulus might be the greater stiffness of alpha-la fibrils. However, the gelation times of alpha-la fibrils are longer than those of beta-lg fibrils.
Improved Analysis of Long-Term Monitoring Data Demonstrates Marked Regional Declines of Bat Populations in the Eastern United States

Bats are diverse and ecologically important, but are also subject to a suite of severe threats. Evidence for localized bat mortality from these threats is well-documented in some cases, but long-term changes in regional populations of bats remain poorly understood. Bat hibernation surveys provide an opportunity to improve understanding, but analysis is complicated by bats' cryptic nature, non-conformity of count data to assumptions of traditional statistical methods, and observation heterogeneities such as variation in survey timing. We used generalized additive mixed models (GAMMs) to account for these complicating factors and to evaluate long-term, regional population trajectories of bats. We focused on four hibernating bat species – little brown myotis (Myotis lucifugus), tri-colored bat (Perimyotis subflavus), Indiana myotis (M. sodalis), and northern myotis (M. septentrionalis) – in a four-state region of the eastern United States during 1999–2011. Our results, from counts of nearly 1.2 million bats, suggest that cumulative declines in regional relative abundance by 2011 from peak levels were 71% (with 95% confidence interval of ±11%) in M. lucifugus, 34% (±38%) in P. subflavus, 30% (±26%) in M. sodalis, and 31% (±18%) in M. septentrionalis. The M. lucifugus population fluctuated until 2004 before persistently declining, and the populations of the other three species declined persistently throughout the study period. Population trajectories suggest declines likely resulted from the combined effect of multiple threats, and indicate a need for enhanced conservation efforts. They provide strong support for a change in the IUCN Red List conservation status in M. lucifugus from Least Concern to Endangered within the study area, and are suggestive of a need to change the conservation status of the other species. Our modeling approach provided estimates of uncertainty, accommodated non-linearities, and controlled for observation heterogeneities, and thus has wide applicability for evaluating population trajectories in other wildlife species.
Using a Serial Marker to Predict a Repeated Measures Outcome in a Cohort Study

Consider the cohort design and suppose that the outcome of primary interest is a continuous random variable observed repeatedly over time. Suppose that the value of a "clinical marker," which is thought to be predictive of the primary outcome, is also recorded. We would like to determine whether there is an association between the two variables as they evolve over time. We might also want to predict the pattern for the primary outcome conditionally on a specific profile of clinical interest for the serial marker. A model is developed to address these issues. One regression model is created for the primary outcome while a second regression model is developed for the clinical marker. The vector autoregressive model, i.e., VAR(1), is used to characterize the covariance structure between the two sets of repeated observations. Hypotheses of interest are described and procedures for testing them are elaborated. The Diabetes Control and Complications Trial is used to illustrate the procedures.
Synopsis of the results from overpressurizing a reinforced concrete containment model

Abstract Sandia National Laboratories completed the testing of a 1:6-scale containment building for a light water reactor in July 1987. Results from this and other containment model testing are being used by the US Nuclear Regulatory Commission to benchmark analytical techniques. The validated techniques can then be used to predict the behavior of actual nuclear power plant containments to a variety of hypothesized severe accidents. The most recent containment building tested was made of reinforced concrete and had many of the features found in full-size containments. Testing consistent of a structural integrity test, and integrated leak rate test, and concluded with an overpressurization test of the structure. Highlights of the results from the overpressurization of the containment model are presented.
Breakdowns and stagnation in iterative methods

One of the disadvantages of Krylov subspace iterative methods is the possibility of breakdown. This occurs when it is impossible to get the next approximation of the solution to the linear system of equationsAu=f. There are two different situations: lucky breakdown, when we have found the solution and hard breakdown, when the next Krylov subspace cannot be generated and/or the next approximate solution (iterate) cannot be computed. We show that some breakdowns depend on the chosen method of generating the basis vectors. Another undesirable feature of the iterative methods is stagnation. This occurs when the error does not change for several iterative steps. We investigate when iterative methods can stagnate and describe conditions which characterize stagnation. We show that in some cases stagnation can imply breakdown.
Race and Regionalism in the Politics of Taxation in Brazil and South Africa

Nationally-specific definitions of citizenship proved decisive for the development of the Tax State in Brazil and South Africa in the twentieth century. Although both countries had been divided along racial and regional lines in the late nineteenth century, watershed constitutions addressed these political problems in very different ways. South Africa's institutionalized white supremacy created a level of political solidarity that contributed to the development of a highly progressive and efficient tax system. In Brazil, federalism and official non-racialism proved more divisive, making the enactment and collection of progressive taxes much more difficult. The legacy of these divergent state-building processes remains evident at the beginning of the twenty-first century. Lieberman extends this analysis to a wider group of country cases and finds similar patterns and causal relationships between the politics of race, region, and taxation. The findings are based on field research, large-scale national surveys, macroeconomic data, and various archival sources.