cssi/SciSciGPT-SciSciNet huggingface dataset:
Electrophysiological Maturation of Cerebral Organoids Correlates with Dynamic Morphological and Cellular Development

Summary Cerebral organoids (COs) are rapidly accelerating the rate of translational neuroscience based on their potential to model complex features of the developing human brain. Several studies have examined the electrophysiological and neural network features of COs; however, no study has comprehensively investigated the developmental trajectory of electrophysiological properties in whole-brain COs and correlated these properties with developmentally linked morphological and cellular features. Here, we profiled the neuroelectrical activities of COs over the span of 5 months with a multi-electrode array platform and observed the emergence and maturation of several electrophysiologic properties, including rapid firing rates and network bursting events. To complement these analyses, we characterized the complex molecular and cellular development that gives rise to these mature neuroelectrical properties with immunohistochemical and single-cell transcriptomic analyses. This integrated approach highlights the value of COs as an emerging model system of human brain development and neurological disease.
Trends in Therapy and Outcomes Associated With Respiratory Failure in Patients Admitted to the Cardiac Intensive Care Unit.

Purpose:To describe the epidemiology, outcomes, and temporal trends of respiratory failure in the cardiac intensive care unit (CICU).Materials and Methods:Retrospective cohort analysis of 2,986 uni...
A serine protease-encoding gene that marks activated cytotoxic T cells in vivo and in vitro

Activated cytotoxic T lymphocytes (CTLs) are presumed to be the effectors in the lysis of virally infected or transformed host cells, the mediators of graft rejection, and the potential culprits in a number of autoimmune diseases. Unfortunately, there is no marker available that specifically identifies these cells in vivo, making it difficult to prove unequivocally that CTLs are the effector cells in these immune functions. Mature T cells are usually divided into subsets on the basis of their surface phenotype: Those that express the CD8 antigen are assumed to be potential cytotoxic cells, and those that express the CD4 antigen, potential helper cells. However, the identification of CD4+CD8- CTLs (Golding et al. 1985) and CD4-CD8+ helper cells (Swain and Panfili 1979) both in vitro and in graft rejection in vivo (Rosenberg et al. 1987) limits the usefulness of this division. A more serious problem with using phenotype to imply function is that these markers are expressed on both active and resting T cells. Thus, they cannot be used to distinguish between the cells participating in a localized immune response and those nonspecifically present at the site. To identify cytotoxic lymphocytes more accurately, we used a molecular genetic approach to isolate genes expressed by these cells.
Clinical Diagnosis and General Laboratory Evaluation

The aims of the initial clinical encounter in a patient with stroke are to: diagnose the cause and extent of the brain and vascular disease in order to quickly begin specific treatment to attempt to minimize brain damage; recognize risk factors for vascular disease so as to institute measures to prevent subsequent cardiac, cerebrovascular, and peripheral vascular disease; recognize medical comorbidities that will impact on the care of the stroke patient and on their general health; and anticipate potential complications of the stroke such as pulmonary and urinary infections and deep vein thrombosis in order to institute measures for preventing these complications. Diagnosis of the cause and extent of the brain and vascular lesions leading to stroke is the most difficult and urgent task for treating physicians. This must be done as quickly as possible in order to prevent or minimize any damage to vital brain regions. Cardiac and vascular imaging tests should be ordered after analysis of the brain imaging results to be sure that the key supply channels in the individual patient are all properly investigated. Noninvasive tests such as ultrasound, magnetic resonance angiography, or spiral computed tomography angiography almost always should precede catheter angiography. It is suggested that some patients whose preliminary tests suggest important coronary artery disease may require coronary angiography.
Multi-Objective Model Selection via Racing

Model selection is a core aspect in machine learning and is, occasionally, multi-objective in nature. For instance, hyper-parameter selection in a multi-task learning context is of multi-objective nature, since all the tasks’ objectives must be optimized simultaneously. In this paper, a novel multi-objective racing algorithm (RA), namely S-Race, is put forward. Given an ensemble of models, our task is to reliably identify Pareto optimal models evaluated against multiple objectives, while minimizing the total computational cost. As a RA, S-Race attempts to eliminate non-promising models with confidence as early as possible, so as to concentrate computational resources on promising ones. Simultaneously, it addresses the problem of multi-objective model selection (MOMS) in the sense of Pareto optimality. In S-Race, the nonparametric sign test is utilized for pair-wise dominance relationship identification. Moreover, a discrete Holm’s step-down procedure is adopted to control the family-wise error rate of the set of hypotheses made simultaneously. The significance level assigned to each family is adjusted adaptively during the race. In order to illustrate its merits, S-Race is applied on three MOMS problems: 1) selecting support vector machines for classification; 2) tuning the parameters of artificial bee colony algorithms for numerical optimization; and 3) constructing optimal hybrid recommendation systems for movie recommendation. The experimental results confirm that S-Race is an efficient and effective MOMS algorithm compared to a brute-force approach. 1 , 2 1 A preliminary version of this paper appeared in [1] .
Colo-rectal Lithobezoar: A Rare Cause of Colonic Obstruction.

Bezoar is the foreign body material in the digestive tract. Primary colonic lithobezoar is rarely reported in childhood and is usually associated with the history of iron deficiency anemia, pica or psycho-social disorders. [1] These cases may present with chronic constipation, recurrent abdominal pain, and painful defecation. Evacuation under anesthesia is the usual treatment, but surgery can be considered if this procedure fails or colonic injury occurs.[2-4]
Artificial neural network for nonlinear projection of multivariate data

The authors propose a learning algorithm to train a multilayer feedforward neural network to perform the well-known Sammon nonlinear projection. The learning algorithm is an extension of the backpropagation algorithm. A significant advantage of the network-based projection over the original Sammon algorithm is that the trained network is able to project new patterns. Experimental results indicate that the projection network has good generalization capability when an appropriately sized training set and network are utilized. A lower bound for the number of free parameters required to achieve the same representation power as Shannon's algorithm is derived. This lower bound, together with the generalization capability, provides some guidelines about the size of the network that should be used. >
DIVERSITY AND NICHE EVOLUTION ALONG ARIDITY GRADIENTS IN NORTH AMERICAN LIZARDS (PHRYNOSOMATIDAE)

Deserts occupy approximately 12% of the Earth's land surface, and are thought to have species poor but highly specialized biotas. However, few studies have examined the evolutionary origins of desert biotas and of diversity patterns along aridity gradients. Further, it is unclear if species occurring in more extreme conditions on a given niche axis (i.e., precipitation) are more specialized for those conditions (i.e., have narrower niche breadths). We address these questions here using a time-calibrated phylogeny and climatic data for 117 species of phrynosomatid lizards. Phrynosomatids are the most species-rich family of lizards in North America, and are found from deserts to rainforests. Surprisingly, we find that phrynosomatids have higher richness in more arid environments. This pattern occurs seemingly because they have been present in more arid habitats longer (~55 million years), and lineages in mesic environments are recently derived from more arid-dwelling ancestors. We find little support for the hypothesis that species in more extreme environments are more specialized. Instead, many desert-dwelling species are broadly distributed, and species in the most mesic environments have the broadest niche breadths. In summary, phrynosomatids offer a counterexample to the idea that arid regions are inhabited by a small number of recent and highly specialized lineages.
Cyclic AMP regulates the migration and invasion potential of human pancreatic cancer cells

Aggressive dissemination and metastasis of pancreatic ductal adenocarcinoma (PDAC) results in poor prognosis and marked lethality. Rho monomeric G protein levels are increased in pancreatic cancer tissue. As the mechanisms underlying PDAC malignancy are little understood, we investigated the role for cAMP in regulating monomeric G protein regulated invasion and migration of pancreatic cancer cells. Treatment of PDAC cells with cAMP elevating agents that activate adenylyl cyclases, forskolin, protein kinase A (PKA), 6-Bnz-cAMP, or the cyclic nucleotide phosphodiesterase inhibitor cilostamide significantly decreased migration and Matrigel invasion of PDAC cell lines. Inhibition was dose-dependent and not significantly different between forskolin or cilostamide treatment. cAMP elevating drugs not only blocked basal migration, but similarly abrogated transforming-growth factor-β-directed PDAC cell migration and invasion. The inhibitory effects of cAMP were prevented by the pharmacological blockade of PKA. Drugs that increase cellular cAMP levels decreased levels of active RhoA or RhoC, with a concomitant increase in phosphorylated RhoA. Diminished Rho signaling was correlated with the appearance of thickened cortical actin bands along the perimeter of non-motile forskolin or cilostamide-treated cells. Decreased migration did not reflect alterations in cell growth or programmed cell death. Collectively these data support the notion that increased levels of cAMP specifically hinder PDAC cell motility through F-actin remodeling.
Exploiting known topologies to navigate with low-computation sensing

Exploiting prior knowledge about the general characteristics of an environment can reduce the amount of sensing required. For example, in an indoor environment floors tend to be flat and walls tend to be straight and static. In such an environment, simple range sensors can provide enough information to support robust sensor-driven goal-directed navigation. This paper will describe a navigation experiment using a real robot, and speculate on how the techniques used can be extended to other domains.
Tracer diffusion in the chromium–nickel system†

Self diffusion of Cr51 in pure chromium, Cr + 20 wt% Ni, Cr + 44 wt% Ni, and Cr + + 65 wt% Ni has been measured over the temperature ranges of 1000 to 1900, 1000 to 1525, and 900 to 1350 °C, respectively. Over the temperature range of 1000 to 1750 °C the Arrhenius plot for the self diffusion of Cr51 in pure Cr is linear and gave the relation D = 1.6 exp (− 81.0/RT) cm2/s. The penetration plots for the experiments on pure chromium and the Cr rich alloys within ≈ 100 deg of the melting point were non linear, yielding two diffusion coefficients. By comparison with results from a single crystal specimen at high temperatures, the higher diffusion coefficients are shown to be due to some type of high temperature grain boundary diffusion process, possibly due to local melting at the grain boundaries. In addition to this, the Arrhenius plots for these systems all exhibit upwards curvature within ≈ 100 deg of the melting point. This is associated with a divacancy contribution to the diffusion process. The penetration plots and Arrhenius plot for the diffusion of Cr51 and Ni63 in the f.c.c. Cr + 65 wt% Ni alloy were all linear, typical of a normal face centered cubic system. No evidence was found for a high temperature structure of chromium other than b.c.c., either from the diffusion data or from associated X-ray experiments.
Five Essential Elements of Crisis Intervention for Communities and Schools When Responding to Technological Disasters

Technological disasters result from human error, negligence, or limitations in perceiving and reducing risk. They are a form of manmade disaster that exerts a devastating effect on impacted individuals, communities, and ecosystems. Because of their negative impacts, technological disasters often erode community connectedness, undermine adaptive coping strategies in victims, contribute to income and social capital loss, result in complicated legal proceedings that can forestall the provision of needed post-disaster resources, and make it difficult for victims to find meaning in their struggles and recover from disaster. However, 5 empirically supported intervention principles may help mitigate some of these negative effects. These include promoting a sense of safety among victims, calming and supporting fearful individuals, engendering a general sense of self-efficacy and collective efficacy, increasing feelings of connectedness, and inspiring hope in discouraged disaster victims. This article discusses th...
A dynamic Bayesian network approach to multi-cue based visual tracking

Visual tracking has been an active research field of computer vision. However, robust tracking is still far from satisfactory under conditions of various background clutter, poses and occlusion in the real world. To increase reliability, This work presents a novel dynamic Bayesian networks (DBNs) approach to multi-cue based visual tracking. The method first extracts multi-cue observations such as skin color, ellipse shape, face detection, and then integrates them with hidden motion states in a compact DBN model. By using particle-based inference with multiple cues, our method works well even in background clutter without the need to resort to simplified linear and Gaussian assumptions. The experimental results are compared against the widely used condensation and KF approaches. Our better tracking results along with ease of fusing new cues in the DBN framework suggest that this technique is a fruitful basis to build top performing visual tracking systems.
A new quadrifilar helix antenna for space communications

This paper presents a new quadrifilar helix antenna designed to deploy on a space craft for space communications. The quadrifilar helix is beryllium based and is deployed on top of a square ground plane. The ground plane is optimized to reduce back lobe radiation and achieve optimal gain and beam width. A trade off analysis is achieved and is discussed herein. The antenna dimensions and structure are studied to preserve operation in the S-band range while preserving stable radiation characteristics.
A method of imaging viscoelastic parameters with acoustic radiation force

Acoustic radiation force has been proposed as a method of interrogating the mechanical properties of tissue. One simple approach applies a series of focused ultrasonic pulses to generate an acoustic radiation force, then processes the echoes returned from these pulses to estimate the radiation-force-induced displacement as a function of time. This process can be repeated at a number of locations to acquire data for image formation. In previous work we have formed images of tissue stiffness by depicting the maximum displacement induced at each tissue location after a finite period of insonification. While these maximum displacement images are able to differentiate materials of disparate mechanical properties, they exploit only a fraction of the information available. In this paper we show that the time-displacement curves acquired from tissue mimicking phantoms exhibit a viscoelastic response which is accurately described by the Voigt model. We describe how the viscous and elastic parameters of this model may be determined from experimental data. Finally, we show phantom images that depict not only the maximum local displacement, but also the viscous and elastic model parameters. These images offer complementary information about the target.
Design and construction of an automated multiobject spectroscopy system

An automated multi-object spectroscopy system (AMOS) is being developed for use on the 3-meter telescope at Lick Observatory. The overall design is compatible with the eventual goal of acquiring up to one hundred spectra simultaneously in a one degree field of view. The speed and accuracy of AMOS preserve the real time decision making and field changing flexibility associated with traditional singlesource observing techniques. AMOS will operate at the 3-meter prime focus and will feed a floor-mounted spectrograph. We describe some engineering design details and the results of laboratory and 1-meter telescope testing of AMOS.
Morphological and physiological changes in Bovicola limbata (Mallophaga : Trichodectidae) reared on diet containing synthetic juvenile hormone.

Premature 3rd molts or supernumerary molts occurred when the Angora-goat biting louse, Bovicola limbata (Gervais), was reared on diet containing 5 or 50 ppm of the mixed isomers of synthetic juvenile hormone (methyl 10-epoxy-7-ethyl-3,ll-dimethyl-2,6-tridecadienoate). Also, 4th- and 5th-stage nymphal forms and 4th- and 5th-stage nymphal-adult-intermediates were observed. Lice fed diet containing 0.5 or 5 ppm of the synthetic hormone survived normally and produced viable eggs, but lice fed diet containing 50 ppm remained nymphs and incapable of depositing eggs (females) or of mating successfully (males).
Negative-pion capture by 4He

Abstract A simple way to explain the recent Virginia experiment on non-radiative π − -capture by 4 He is discussed.
Effects of antinutrient proteins on Hessian fly (Diptera: Cecidomyiidae) larvae.

Abstract One strategy to enhance the durability of Hessian fly resistance (R) genes in wheat is to combine them with transgenes for resistance. To identify potential transgenes for resistance a protocol for rapidly screening the proteins they encode for efficacy toward resistance is required. However, the Hessian fly is an obligate parasite of wheat and related grasses. Consequently, no protocol for in vitro delivery of antinutrient or toxic proteins to feeding larvae is available. We report here the development of a H essian fly i n planta t ranslocation (HIT) feeding assay and the evaluation of eight lectins and the Bowman–Birk serine proteinase inhibitor for potential in transgenic resistance. Of the antinutrient proteins evaluated, Galanthus nivalis L. agglutinin (GNA), commonly termed snowdrop lectin, was the most efficacious. Ingestion of GNA caused a significant reduction in growth of Hessian fly larvae, disruption of midgut microvilli, and changes in transcript level of genes involved in carbohydrate metabolism, digestion, detoxification, and stress response. These effects of GNA are discussed from the perspective of larval Hessian fly physiology.
Organic Thin Film Transistors based on Pentacene and PTCDI as the Active Layer and LiF as the Insulating Layer

Due to the advantages of low production cost, flexibility and low temperature fabrication, much effort has been devoted to the development of organic electronic devices such as light emitting diodes, photovoltaics and transistors. Organic thin film transistors have several important applications such as switching devices for active-matrix OLED displays, smart cards, identification tags and sensors [1-3]. However, the low carrier mobility in organic materials and the difficulty of integrating organic devices into inorganic processing procedures have hindered the development of organic transistors that are comparable to traditional transistors [4]. Much effort has been devoted to develop new organic materials with higher carrier mobility, while retaining the same conventional inorganic metal-oxide-semiconductor structures. Lithium fluoride (LiF) has the largest band gap and the largest negative electron affinity of any solid, [5] making it a superb candidate for use in the insulating layer of transistors. Using LiF as the gate dielectric layer can facilitate the organic transistor fabrication. In this work, thin film transistors based on pentacene and PTCDI-C8 (N,N′-Dioctyl-3,4,9,10-perylenedicarboximide) as organic semiconductor layers and LiF as gate dielectrics are studied. The electrical properties of these devices have been investigated in atmospheric conditions and under variable light exposure. Output and transfer characteristics of several photo-responsive thin film transistors using different organic materials but with the same insulating layer will be presented and the increase of drain-source current upon illumination will be discussed based on the photoconduction properties of the transistor active layer.
The NASCAR experience: Examining the influence of fantasy sport participation on ‘non-fans’

While NASCAR has traditionally been among the most watched sports in the US, the brand has suffered due to economic conditions and waning interest. As a result, NASCAR has focused its promotional efforts on new marketing and revenue-generating strategies to raise awareness of the sport. One way to increase awareness is through fantasy sports, which have seen a marked uptick in global popularity. However, using fantasy sports to activate involvement among self-described non-fans of a particular sport remains a relatively unexplored area. The purpose of this study was to examine the influence of fantasy sports on attitude and certain behavioral factors using a mixed-method, comparison group design. Employing the path analytic model to examine relationships among variables, results indicate significant differences between study conditions and regression analyses show how patronage intentions were influenced. Focus group data buttress the quantitative results and support the use of fantasy sports as a way to convert self-identified sport non-fans into involved fans.
Bayesian normalization model for label-free quantitative analysis by LC-MS

We introduce a new method for normalization of data acquired by liquid chromatography coupled with mass spectrometry (LC-MS) in label-free differential expression analysis. Normalization of LC-MS data is desired prior to subsequent statistical analysis to adjust variabilities in ion intensities that are not caused by biological differences but experimental bias. There are different sources of bias including variabilities during sample collection and sample storage, poor experimental design, noise, etc. In addition, instrument variability in experiments involving a large number of LC-MS runs leads to a significant drift in intensity measurements. Although various methods have been proposed for normalization of LC-MS data, there is no universally applicable approach. In this paper, we propose a Bayesian normalization model (BNM) that utilizes scan-level information from LC-MS data. Specifically, the proposed method uses peak shapes to model the scan-level data acquired from extracted ion chromatograms (EIC) with parameters considered as a linear mixed effects model. We extended the model into BNM with drift (BNMD) to compensate for the variability in intensity measurements due to long LC-MS runs. We evaluated the performance of our method using synthetic and experimental data. In comparison with several existing methods, the proposed BNM and BNMD yielded significant improvement.
On the Genealogy of a Rare Allele

The gene genealogy is derived for a rare allele that is descended from a mutant ancestor that arose at a fixed time in the past. Following Thompson (1976, Amer. J. Human Genet. 28, 442-452), the fractional linear branching process is used as a model of the demography of a rare allele. The model does not require the total population size to be constant or the mutant class to be neutral; so long as individuals in the class are selectively equivalent, the class as a whole may have a selective advantage, or disadvantage, relative to other alleles in the population. An exact result is given for the joint probability distribution of the coalescence times among a sample of alleles descended from the mutant. A method is described for rapidly simulating these coalescence times. The relationship between the genealogical structure of a discrete generation branching process and a continuous generation birth-death process is elucidated. The theory may be applied to the problem of estimating the ages of rare nonrecurrent mutations.
Two‐dimensional electron gas magnetic field sensors

We describe the use of accumulation layers of electron charge in applications as magnetoresistive devices. We consider two such systems: an InGaAs/InP heterostructure in which we identify a two‐dimensional electron gas from the observation of the quantum Hall effect, and InAs films, in which a strong surface accumulation of charge is inferred from depth profiling studies of the galvanomagnetic coefficients. Magnetoresistive devices fabricated from these materials exhibit outstanding field sensitivity and temperature stability due to the existence of electrons of relatively high density and mobility in the accumulation regions. We also model the magnetosensitivity of our devices.
Development of inferences over elementary-school grades: II. Retention of explicit and implicit words

Elementary-school students in Grades 3–8 were read sentences containing either explicit or implicit names of tools. There was a reliable increment over grades in the number of implicit tools recalled, as measured by a word-stem-completion task; a sharp increase occurred from combined third- and fourth-grade classes to combined fifth- and sixth-grade classes, with a lesser increment from the latter to combined seventh- and eighth-grade classes. Smaller, statistically nonreliable increments occurred in recall of explicitly named tools. The results suggest that there is an increment in the generation of inferences over the early grades.
Relative Superiority of Key Centrality Measures for Identifying Influencers on Social Media

Marketers have been increasingly turning to social media for marketing campaigns, including viral marketing. A key step in viral marketing is to identify influencers in order to maximize the reach of a marketing message. Existing research shows that centrality measures, such as degree and betweenness, are effective methods for influencer identification. However, viral marketing models used in different studies vary greatly, making it difficult to compare findings across the studies. In this paper, the authors built an agent-based framework of viral marketing that supports different experiment settings, such as different network structures and information diffusion modes, and used it to study relative superiority of various centrality measures. The results show that relative superiority of the measures are affected by some factors, but not as much by others. Practical implications of the results are discussed.
A computational study of enantioselective adsorption in a homochiral metal–organic framework

The potential application of a homochiral metal–organic framework (MOF) made from cadmium corners and BINOL-type linkers for enantioselective separations of chiral hydrocarbons was investigated using grand canonical Monte Carlo simulations. Adsorption of racemic mixtures of (R,S)-1,3-dimethyl-1,2-propadiene, (R,S)-1,2-dimethylcyclobutane and (R,S)-1,2-dimethylcyclopropane was simulated. The results show that an enantiomeric excess (ee) of over 50% can be achieved for 1,3-dimethyl-1,2-propadiene, while more moderate ee values were observed for the cyclic compounds. The adsorption sites, diastereomeric complexes and adsorption energies were analysed to understand the enantioselective adsorption. It is shown that the small zigzag pores of the homochiral MOF account primarily for the enantioselective adsorption, whereas the larger helical pores show almost no enantioselectivity. The results also demonstrate that both intrinsic enantioselectivity and accessibility of the adsorption sites are important for the ...
Cytotoxicity and DNA-protein crosslink formation in rat nasal tissues exposed to vinyl acetate are carboxylesterase-mediated

Vinyl acetate is used in the paint, adhesive, and paper board industries. Vinyl acetate is a nasal carcinogen in rats exposed by inhalation for 2 years to 200 and 600 ppm, but not 50 ppm. Previous studies from our laboratory suggest that rat liver microsome-activated vinyl acetate induces plasmid DNA-histone crosslinks, in vitro, through esterase-mediated metabolism. Since nasal tissues contain high levels of carboxylesterase, tumorigenesis may be related to in situ production of the hydrolysis products acetaldehyde and acetic acid. Vinyl acetate was cytotoxic to both respiratory and olfactory tissues in vitro at 50-200 mM, but not 25 mM, after 2 hr exposure. Pretreatment of rats with the carboxylesterase inhibitor, bis-(p-nitrophenyl) phosphate (BNPP), attenuated the cytotoxic effects and metabolism of vinyl acetate in both tissue types. Semicarbazide, an aldehyde scavenger, was unable to protect the tissues from vinyl acetate-induced cytotoxicity. When the metabolites were tested, acetic acid, but not acetaldehyde, was cytotoxic to both tissues. The induction of DNA-protein crosslink (DPXL) formation by acetaldehyde and vinyl acetate in rat nasal epithelial tissues was detected using a sodium dodecyl sulfate/KCl precipitation technique. Endogenous crosslink levels ranged from 0.5 to 2.0% of total DNA and were considered background. Epithelial cells isolated from both olfactory and respiratory turbinates exhibited dose- and time-dependent increases in DPXL formation when exposed to 10-150 mM acetaldehyde for 1-2 hr at 37 degrees C. Similarly, respiratory and olfactory epithelial cells exposed to 5-75 mM vinyl acetate for 1-2 hr accumulated up to 12- and 15-fold higher crosslink levels than untreated cells, respectively. However, vinyl acetate appears to induce much higher levels of DPXLs at equimolar doses than acetaldehyde. This is thought to be related to stimulation of acetaldehyde-induced DPXL formation by the pH lowering effect of acetic acid production (via vinyl acetate hydrolysis). Pretreatment of the nasal turbinates with 1 mM BNPP reduced 25 mM vinyl acetate-induced DPXL formation by over 75% in both tissues. These data support a hypothesis that carboxylesterase-mediated hydrolysis of vinyl acetate is necessary to generate the active intracellular cross-linking agent, acetaldehyde, and the cytotoxic metabolite, acetic acid.
On selection with restriction

In this paper, we .consider the problem of prediction of an unobserved variable and then selecting a group of individuals which are superior with respect to this variable. It is desired at the same time that for this group, mean values of other unobserved variables or some other function of some variable are above certain prespecified levels. We provide the methods of computing the decision rules for these problems. These problems may be termed as the problems of restricted prediction.
Kinetics of acetyl radical formation from methyl radicals and carbon monoxide and crystal structures of two acetylcobalt complexes

Methyl radicals react with macrocyclic cobalt complexes (H[sub 2]O)[sub 2]LCo[sup 2+] (L[sup 1] = 1,4,8,11-tetraazacyclotetradecane, L[sup 2] = C-meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) in the presence of CO in acidic aqueous solution. The reaction yields a mixture of methyl and acetyl complexes as a result of the competition between CO and (H[sub 2]O)[sub 2]CoL[sup 2+] for CH[sub 3][center dot]. Kinetic competition experiments yielded the rate constant for the capture of CH[sub 3][center dot] by CO, k[sub CO] = (2.0 [+-] 0.3) [times] 10[sup 6] M[sup [minus]1] s[sup [minus]1]. The acetyl complex of CoL[sup 1] crystallizes with either H[sub 2]O or ClO[sub 4][sup [minus]] coordinated trans to the acetyl group. Both the red [(ClO[sub 4])L[sup 1]CoC(O)CH[sub 3]](ClO[sub 4]) (1) and the yellow [(H[sub 2]O)L[sup 1]-CoC(O)CH[sub 3]](ClO[sub 4])[sub 2][center dot]H[sub 2]O (2) crystallize in the centric space group P2[sub 1]/c with four molecules in a unit cell of dimensions a = 10.539 (1) [angstrom], b = 12.548 (2) [angstrom], c = 14.915 (2) [angstrom], and [beta] = 93.74 (3)[degree] for 1 and a = 12.588 (3) [angstrom], b = 8.821 (3) [angstrom], c = 19.398 (5) [angstrom], and [beta] = 96.34 (2)[degree] for 2. The data refined to final values of the unweighted R factors ofmore » 0.037 (1) and 0.054 (2).« less
Enhancing the lithiation rate of silicon nanowires by the inclusion of tin

Silicon (Si) has a very high lithium storage capacity and is being explored as a negative electrode material in lithium-ion batteries (LIBs). Si nanowires can exhibit relatively stable performance for many cycles of charging; however, conductive carbon must often be added to the electrode layer to improve the rate capability due to the relatively low electrical conductivity of Si. The added carbon lowers the capacity of the electrode. Here, we show that the rate capability of Si in LIBs can be substantially enhanced by incorporating tin (Sn) into Si nanowires. The solubility of Sn in Si is very low (0.015 at%); yet, Sn used as a seed for supercritical fluid–liquid–solid (SFLS) growth can be trapped in Si nanowires with relatively high concentration (10 at%). Such Sn-containing Si nanowires and no added conductive carbon in the electrode layer, could be cycled in LIBs with high capacity (∼1000 mA h g−1 over 100 cycles) at a current density of 2.8 A g−1 (1 C). Capacities exceeding that of graphite could still be reached at cycle rates as high as 2 C. Real-time in situ transmission electron microscopy (TEM) revealed that lithiation occurs five times faster in Si nanowires with significant amounts of Sn than in the Si nanowires without Sn, and twice as fast as in nanowires that were coated with carbon.
An embedded level set method for sharp-interface multiphase simulations of Diesel injectors

Abstract We propose a comprehensive approach for treating complex wall boundaries in two-phase, free-surface flow simulations on a Cartesian adaptive grid. The external gas–liquid interface is handled by the well-known combined level-set volume-of-fluid (CLSVOF) method. The new element is the coupling with the wall boundary representation using a second level-set function. The no-slip boundary condition at the walls is enforced by properly populating the ghost cells of a narrow band inside the solid body, using a simple and numerically robust treatment of the contact line. In this framework, merging and separation of multiple solid bodies are easily accommodated. Verification tests with grid convergence analysis are presented for a stationary/oscillating body in single-phase flow and for a drop on an inclined plane. Two examples demonstrate the suitability of the proposed approach to study liquid injection. The first is a validation study with data from a scaled-up Diesel injector, to demonstrate how the seamless calculation of internal flow and jet primary atomization can be accomplished. The second is a demonstration of transient atomization response to a measured three-dimensional needle displacement of the injector.
On crack-crack interaction and coalescence in fatigue

Abstract The effect of crack-crack interaction and coalescence in fatigue was studied for a single pair of cracks analytically and for multi-cracks based on real microstructure variations by means of Monte Carlo simulations. Crack-crack interaction and coalescence lower the mean fatigue lifetime. The magnitude of lowering increases with increasing crack density and becomes particularly important in the low failure probability regime. Results of this investigation provide insight for laying the foundation of quantitative predictive technology on crack interaction and coalescence aspects of fatigue.
Fibronectin and VLA-4 in haematopoietic stem cell–microenvironment interactions

THE self-renewal and differentiation of haematopoietic stem cells occurs in vivo and in vitro in direct contact with cells making up the haematopoietic microenvironment1–4. In this study we used adhesive ligands and blocking antibodies to identify stromal cell-derived extracellular matrix proteins involved in promoting attachment of murine haematopoietic stem cells. Here we report that day-12 colony-forming-unit spleen (CFU-S12)5 cells and reconstituting haematopoietic stem cells attach to the C-terminal, heparin-binding fragment of fibronectin by recognizing the CS-1 peptide of the alternatively spliced non-type III connecting segment (IIICS) of human plasma fibronectin. Furthermore, CFU-S12 stem cells express the α4 subunit of the VLA-4 integrin receptor, which is known to be a receptor for the CS-1 sequence, and monoclonal antibodies against the integrin α4 subunit of VLA-4 block adhesion of CFU-S12 stem cells to plates coated with the C-terminal fibronectin fragment. Finally, polyclonal antibodies against the integrin β1 subunit of VLA-4 inhibit the formation of CFU-S12-derived spleen colonies and medullary haematopoiesis in vivo following intravenous infusion of antibody-treated bone marrow cells.
Time course of the development of the enhanced behavioral and biochemical responses to amphetamine after pretreatment with amphetamine.

Abstract These experiments were designed to examine the time course of development of the enhanced stereotyped behavioral response to amphetamine after withdrawal from chronic pretreatment with amphetamine and to determine whether this time course correlates with that of the enhancement in the amphetamine-induced stimulation of the release of dopamine (DA) from striatal slices. Rats were pretreated with amphetamine (5 mg/kg, i.p.) or saline, twice daily for 5 consecutive days. At 3, 15 and 30 days after withdrawal of the drug the stereotyped behavioral response and the release of endogenous DA from slices of striatum in response to a challenge dose of amphetamine were measured. At all 3 times tested, the stereotyped behavioral response to the challenge dose of amphetamine was enhanced in the rats pretreated with amphetamine, with the greatest degree of enhancement seen at 15 and 30 days after withdrawal of the drug. At these times, the responses were associated with a significant attenuation in the stimulation of locomotor activity produced by the challenge dose of amphetamine, which was probably related to the enhanced stereotyped behavioral response. Amphetamine stimulated the release of endogenous DA from slices of striatum in rats pretreated with saline and amphetamine. However, the release of endogenous DA from slices of rats pretreated with amphetamine was significantly greater than that of saline-pretreated rats at 15 and 30 days after withdrawal of the drug, but not at 3 days after withdrawal. Thus, pretreatment with amphetamine resulted in enhanced behavioral and biochemical responses to amphetamine which increased over time after withdrawal of the drug. These results suggest that the enhanced behavioral response to amphetamine may be due to increased sensitivity of dopaminergic neurons in the striatum to the releasing actions of amphetamine.
Enterprise Risk and Return Management for Financial Institutions

Abstract It is important to include both risk and return in finding the optimal balance of assets and liabilities for financial institutions. Insurance companies, with their range of sophisticated assets and liabilities, are perhaps the best example of the value of such an approach. Examples in the paper refer to the insurance industry, but parallels to other types of financial institutions are easily drawn. The analysis in the paper shows that a comprehensive approach to risk and return produces some interesting conclusions with respect to asset allocation, active versus passive asset management, and the mix and pricing of liabilities.
Long-term behavioral effects of cognitive dissonance.

Abstract The study was conducted to investigate whether or not the arousal of cognitive dissonance can produce long-term behavioral effects. Children were told not to play with a very desirable toy under high or low threat, and were left alone with the toy. Those who did not play with it were given a second opportunity to play with the toy several weeks later, with the original trreat removed. The prediction was that those subjects who had resisted temptation under mild threat would be less likely to play with the toy in this second session than would those who had resisted under severe threat. The results supported this prediction.
Micropatterned substrates: Approach to probing intercellular communication pathways

Intercellular signaling is critical for the normal development and physiology of the central nervous system (CNS). To study such signaling, it is vital to control where and when the cells make contact with one another. It is also important to determine whether the process used for cell localization has an impact on signaling. This paper describes a technique that controls the location for cell growth in vitro and demonstrates that the technique has minimal (if any) impact on intercellular signaling. By using photolithographic methods, poly(dimethylsiloxane) molds were fabricated to function as templates for micrometer-level patterning of a nonadhesive agar (agarose) onto glass coverslips coated with a cell adhesive film (poly(L-lysine)). This process yields a surface composed of well-defined adhesive and nonadhesive microdomains. When endothelia or astrocytes are plated onto these substrates, confluent domains of endothelia or astrocytes grow on the poly(L-lysine) domains. Cocultures of astrocytes and neurons can also successfully be used to form interwoven networks on the adhesive domains. Moreover, studies of calcium signaling revealed that astrocytes grown on such patterns retain their native physiological activity. This conclusion is based on the observed propagation rate for calcium waves within individual astrocyte domains and across neighboring, but spatially disconnected, astrocyte domains. The potential to apply these micropatterned substrates as platforms for interrogating communication pathways in key components of the CNS is discussed.
Teacher training, teacher quality and student achievement

Abstract We study the effects of various types of education and training on the productivity of teachers in promoting student achievement. Previous studies on the subject have been hampered by inadequate measures of teacher training and difficulties in addressing the non-random selection of teachers to students and of teachers to training. We address these issues by estimating models that include detailed measures of pre-service and in-service training, a rich set of time-varying covariates, and student, teacher, and school fixed effects. We find that elementary and middle school teacher productivity increases with experience (informal on-the-job training). The largest gains from experience occur in the first few years, but we find continuing gains beyond the first five years of a teacher's career. In contrast, we do not find a consistent relationship between formal professional development training and teacher productivity. However, this may be partly driven by estimation issues as we find more significant positive effects of formal training in the subject-grade combination where estimates should be most precise (middle school math). There is no evidence that teachers' pre-service (undergraduate) training or college entrance exam scores are related to productivity.
A Poset-based Approach to Embedding Median Graphs in Hypercubes and Lattices

A median graph G is a graph where, for any three vertices u, v and w, there is a unique node that lies on a shortest path from u to v, from u to w, and from v to w. While not obvious from the definition, median graphs are partial cubes; that is, they can be isometrically embedded in hypercubes and, consequently, in integer lattices. The isometric and lattice dimensions of G, denoted as dim I (G) and dim Z (G), are the smallest integers k and r so that G can be isometrically embedded in the k-dimensional hypercube and the r-dimensional lattice respectively. Motivated by recent results on the cover graphs of distributive lattices, we study these parameters through median semilattices, a class of ordered structures related to median graphs. We show that not only does this approach provide new combinatorial characterizations for dim I (G) and dim Z (G), they also have nice algorithmic consequences. Assume G has n vertices and m edges. We prove that dim I (G) can be computed in O(n + m) time, and an isometric embedding of G on a hypercube with dimension dim I (G) can be constructed in O(n × dim I (G)) time. The algorithms are extremely simple and the running times are optimal. We also show that dim Z (G) can be computed and an isometric embedding of G on a lattice with dimension dim Z (G) can be constructed in $O( n \times dim_I(G) + dim_I(G)^{2.5})$ time by using an existing algorithm of Eppstein’s that performs the same tasks for partial cubes. We are able to speed up his algorithm by using our framework to provide a new “interpretation” to the algorithm. In particular, we note that its main part is essentially a generalization of Fulkerson’s method for finding a smallest-sized chain decomposition of a poset.
Editorial introduction to the special issue: new scholarship in Japan sport studies

The 20th-century sports world of Japan was centered on baseball and sumo, and both sports drew much of the attention of sport scholars. This special issue show cases new directions in Japan sports studiestowards other sports and towards analysis of sport and broader social issues like disability, political issues like ethnicity, and historical questions of nationalism, colonial rule, and class formation.
A numerical study of the effect of particle properties on the radial distribution of suspensions in pipe flow

Abstract We employ a Lagrangian–Lagrangian (LL) numerical formalism to study two- and three-dimensional (2D, 3D) pipe flow of dilute suspensions of macroscopic neutrally buoyant rigid bodies at flow regimes with Reynolds numbers (Re) between 0.1 and 1400. A validation study of particle migration over a wide spectrum of Re and average volumetric concentrations demonstrates the good predictive attributes of the LL approach adopted herein. Using a scalable parallel implementation of the approach, 3D direct numerical simulation is used to show that (1) rigid body rotation affects the behavior of a particle laden flow; (2) an increase in neutrally buoyant particle size decreases radial migration; (3) a decrease in inter-particle distance slows down the migration and shifts the stable position further away from the channel axis; (4) rigid body shape influences the stable radial distribution of particles; (5) particle migration is influenced, both quantitatively and qualitatively, by the Reynolds number; and (6) the stable radial particle concentration distribution is affected by the initial concentration. The parallel LL simulation framework developed herein does not impose restrictions on the shape or size of the rigid bodies and was used to simulate 3D flows of dense, colloidal suspensions of up to 23,000 neutrally buoyant ellipsoids.