cssi/SciSciGPT-SciSciNet huggingface dataset:
Up-regulation of neurosteroid biosynthesis as a pharmacological strategy to improve behavioural deficits in a putative mouse model of post-traumatic stress disorder.

Benzodiazepines remain the most frequently used psychotropic drugs for the treatment of anxiety spectrum disorders; however, their use is associated with the development of tolerance and dependence. Another major hindrance is represented by their lack of efficacy in many patients, including patients with post-traumatic stress disorder (PTSD). For these nonresponders, the use of selective serotonin reuptake inhibitors (SSRIs) has been the therapy of choice. In the past decade, clinical studies have suggested that the pharmacological action of SSRIs may include the ability of these drugs to normalise decreased brain levels of neurosteroids in patients with depression and PTSD; in particular, the progesterone derivative allopregnanolone, which potently, positively and allosterically modulates the action of GABA at GABAA receptors. Preclinical studies using the socially-isolated mouse as an animal model of PTSD have demonstrated that fluoxetine and congeners ameliorate anxiety-like behaviour, fear responses and aggressive behaviour expressed by such mice by increasing corticolimbic levels of allopregnanolone. This is a novel and more selective mechanism than serotonin reuptake inhibition, which, for half a century, has been considered to be the main molecular mechanism for the therapeutic action of SSRIs. Importantly, this finding may shed light on the high rates of SSRI resistance among patients with PTSD and depression, comprising disorders in which there appears to be a block in allopregnanolone synthesis. There are several different mechanisms by which such a block may occur, and SSRIs may only be corrective under some conditions. Thus, the up-regulation of allopregnanolone biosynthesis in corticolimbic neurones may offer a novel nontraditional pharmacological target for a new generation of potent nonsedating, anxiolytic medications for the treatment of anxiety, depression, and PTSD: selective brain steroidogenic stimulants.
Modeling Languages: Declarative and Imperative Descriptions of Chemical Reactions and Processing Systems

Publisher Summary This chapter describes two modeling languages: Language for Chemical Reasoning (LCR) and MODELing LAnguage (MODEL.LA.). Both are based on the same principles and have a common structure. The chapter describes the components of a modeling language, called LCR that was developed to represent the knowledge about chemically reacting systems. First, the basic modeling elements that constitute the building blocks for the representation of the declarative knowledge about molecules, reactions, and pathways have been described. Second, the semantic relationships among the basic modeling elements have been discussed. These semantic relationships establish the “meaning” behind the linguistic expressions, defining knowledge about molecules and reactions. Third, the syntax used by the language for the description of chemically reacting systems has been presented. The nine basic modeling elements of LCR are generic enough to allow (1) infinite extensibility of LCR's vocabulary through a finite set of rules, and (2) representation and analysis of any potential reaction pathway. The chapter also examines the mechanisms that LCR possesses to achieve these objectives. MODEL.LA. is a high-level, special-purpose language that was developed to support the modeling activities of a broad range of process engineering tasks; process design, simulation, operations planning, diagnosis, configuration of control systems, and others. MODEL.LA. is quite distinct in both scope and capabilities from other modeling languages such as Advanced System for Computations in ENgineering Design (ASCEND), MODeling Assistant (MODASS), and Object-oriented Modeling Language (OMOLA). MODEL.LA. shares many common features with LCR. Both languages share a common set of semantic relationships and a common syntax. They differ in their modeling elements that reflect the different vocabularies of chemistry and process engineering. The modeling elements of each language are organized into subsets, which depict the structural and behavioral knowledge of the corresponding domains. The chapter provides an overview of MODEL.LA.'s structure and discusses the utilization of MODEL.LA. within the scope of engineering problems.
Gas Laser Instabilities and their Interpretation

Although the special interests of many laser researchers relate to instabilities and chaos in lasers and nonlinear optical systems, it is well to recall that in a mathematical sense many of the specific phenomena in which we are interested have long been recognized and studied in nonoptical systems. Maintaining this broader perspective can sometimes provide insight into the types of behavior that might or might not be expected in optics-related experiments. Thus, it may be noted that periodic oscillations in mechanical systems have been known for millennia, and this fact may be illustrated by a consideration of the ancient history of music and musical instruments. Early studies in music were directed toward such ideals as purity of tone, beauty of melody, richness of harmony, and elegance of rhythm. (Listening to a teenager’s radio, however, soon reveals that, as in optics, such ideals are sometimes now abandoned in favor of an emphasis on power, noise, and chaos.) The study of periodic instabilities in electrical systems is a somewhat more recent area of endeavor, but it still dates back centuries. The earliest electrical oscillators were electro-mechanical systems which today might simply be referred to as electric motors. These were followed in the last century by electroacoustical oscillators motivated by the problem of positive feedback in telephone repeaters. The first modern electronic oscillators used the triode vacuum tube (audion) and were reported in 1915.1 The first electronic circuit that may have produced a chaotic output was the sinusoidally-driven glow-lamp relaxation oscillator described by van der Pol and van der Mark in 1927, and those authors remark on “an irregular noise” at transitions between locking states.2,3 Van der Pol’s subsequent work with forced triode circuits inspired the forced van der Pol equation, that has been of great interest to mathematicians. The first autonomous circuits to exhibit chaotic behavior may have been glow-lamp ring oscillators. It was reported by Ives in 1958 that these circuits sometimes perform “erratically” and are hard to adjust for a specific firing order.4 Besides chaotic behavior, these circuits can also exhibit a large number of independent limit cycles.5
Photovoltaic systems overview

Selected photovoltaic systems currently under user-environment field test by the U.S. Department of Energy Photovoltaics Program are discussed, and operational results are summarized. There are many systems in the stand-alone sector that are cost effective now. As proven products become available, distributed residential, commercial, institutional and industrial on-site systems should be able to displace significant amounts of centrally-generated electricity throughout most of the United States. Finally, utilities should ultimately be able to augment their generating capacity with larger-scale systems. Field experience and industry interface has led to excellent overall product performance.
Hepatic focal nodular hyperplasia: findings with color Doppler sonography

Color Doppler sonographic images of five patients with a total of six lesions of FNH were reviewed. All cases were confirmed pathologically. All six lesions showed increased intralesional flow in comparison to surrounding liver parenchyma on color Doppler sonography. Four of the six lesions showed significant peripheral flow; two of the six lesions showed central flow radiating peripherally from a central vessel. We conclude that increased color Doppler flow may be a characteristic feature of FNH. Increased internal flow has also been reported in HCC and hepatic metastatic disease. Considerable overlap is seen in color Doppler flow patterns. However, in patients clinically at low risk for malignancy, detection of a liver mass with increased color Doppler flow should suggest the diagnosis of FNH.
Unsupervised deep feature learning for deformable registration of MR brain images

Establishing accurate anatomical correspondences is critical for medical image registration. Although many hand-engineered features have been proposed for correspondence detection in various registration applications, no features are general enough to work well for all image data. Although many learning-based methods have been developed to help selection of best features for guiding correspondence detection across subjects with large anatomical variations, they are often limited by requiring the known correspondences (often presumably estimated by certain registration methods) as the ground truth for training. To address this limitation, we propose using an unsupervised deep learning approach to directly learn the basis filters that can effectively represent all observed image patches. Then, the coefficients by these learnt basis filters in representing the particular image patch can be regarded as the morphological signature for correspondence detection during image registration. Specifically, a stacked two-layer convolutional network is constructed to seek for the hierarchical representations for each image patch, where the high-level features are inferred from the responses of the low-level network. By replacing the hand-engineered features with our learnt data-adaptive features for image registration, we achieve promising registration results, which demonstrates that a general approach can be built to improve image registration by using data-adaptive features through unsupervised deep learning.
How Cannabis Acts

The Science of Marijuana. Leslie L. Iversen. Oxford University Press, Oxford, 2000. 301 pp. 29.95, £18.99. ISBN 0-19-513123-1. An important contributor to the House of Lords Select Committee report on cannabis, Iversen provides a well-balanced account of the scientific background for the current debates on the uses of marijuana.
A Diamond-Shaped Equiponderant Graphical Display of the Effects of Two Categorical Predictors on Continuous Outcomes

Three-dimensional (3-D) bar graphs and their current 2-D alternatives have certain limitations when the primary objective is to provide an equal representation of the effects of two predictors on an outcome. This article proposes a graphing methodology (in the shape of a diamond) that projects 3-D bar graphs into 2-D whereby the third dimension is replaced with a polygon whose area and middle vertical and horizontal lengths represent the outcome. The proposed graphical representation is invariant to rotations and avoids outcomes in categories being concealed by others. This article shows several applications of our proposal to a variety of data types (e.g., proportions, incidence rates, relative risks), which can be easily implemented with available software.
Varied shock and simple escape.

5 groups of rats were trained on an operant escape task under high, intermediate, or low shock conditions. Each of 3 groups received one of these intensities on all days and trials. The fourth group alternated between high and low shock intensities on consecutive days and the fifth group between high and low shock intensities randomly on consecutive trials within a day. High-intensity shock elicited faster escape responding than did low-intensity shock. Responding at a given shock level was similar regardless of the schedule of shock presentation (i.e., constant, alternated, or random). It was concluded that drive level on a given trial was the major determinant of performance.
Experimental investigation of apex fence flaps on delta wings

The effects on leading edge vortex formation produced by apex fences mounted on two delta wings were examined in a subsonic wind tunnel. Pressure data were collected on the upper surface of the test wings and oil flow and bubble flow visualizations were performed. The deflections studied were 74, 90 and 65 deg in one-sided and two-sided configurations. Full span and semi-span delta wing planforms were used. Relatively small, symmetrically deployed apex fences provided enhanced upper surface suction which, in some angle-of-attack situations, could lead to a pitch-up force. Asymmetrically-deployed fences showed promise for yaw control at high angles of attack, althouh the force effectiveness has yet to be quantified.
Dibutyryl cyclic AMP resistant MDCK cells in serum free medium have reduced cyclic AMP dependent protein kinase activity and a diminished effect of PGE1 on differentiated function

Prostaglandin E1 (PGE1) has a stimulatory effect both on the growth and the expression of differentiated function of Madin Darby Canine Kidney (MDCK) cells in a hormonally defined medium (Medium K-1). While the stimulatory effect of PGE1 on MDCK cell growth is observed in subconfluent cultures, the effect of PGE1 on differentiated function (i.e., dome formation) is observed at confluency. PGE1 may possibly affect growth and such differentiated functions by separate mechanisms. In order to examine this possibility, dibutyryl cyclic AMP resistant variants of MDCK were selected. All of the variants were partially resistant to the growth inhibitory effects of dibutyryl cyclic AMP and theophylline. The cyclic AMP dependent protein kinase activity of four of the five variant clones studied was significantly reduced as compared with normal MDCK cells. The dependence of the kinase activity of several of the dibutyryl cyclic AMP resistant variants (DBr2 and DBr3) on the cyclic AMP concentration in the reaction mixture was compared with that of normal MDCK cells. At all of the cyclic AMP concentrations tested DBr2 and DBr3 cells had reduced protein kinase activity as compared with normal MDCK cells. This reduced activity could be attributed to a decrease in the Vmax for kinase in the two variants, rather than to a change in the Km of kinase for cyclic AMP. The cyclic AMP phosphodiesterase activity of dibutyryl cyclic AMP resistant variants was also studied. Unlike PGE1 independent clone 1, DBr2 and DBr3 cells did not differ significantly from normal MDCK cells with regard to their ability to degrade cyclic AMP. The growth and functional responsiveness of DBr2 and DBr3 cells to PGE1 was also examined. DBr2 and DBr3 cells were shown to retain a normal growth response to PGE1. However the capacity of DBr2 and DBr3 cells to form domes in response to PGE1 was dramatically reduced as compared with normal MDCK cells. Nevertheless DBr3 cells were shown to still retain the capacity to form domes in response to other inducers. The effect of PGE1 on one of the functional parameters involved in dome formation (the activity of the Na+/K+ ATPase) was examined. The rate of ouabain-sensitive Rb+ uptake was observed to be elevated in confluent monolayers of normal MDCK cells maintained in Medium K-1, as compared with monolayers maintained in Medium K-1 minus PGE1. In contrast in confluent DBr3 monolayers, the rate of ouabain-sensitive Rb+ uptake was significantly lower than in normal MDCK monolayers, both in Medium K-1 and in K-1 minus PGE1, and a stimulatory effect of PGE1 on Rb+ uptake was not observed. These observations indicate that we have isolated a second class of variants which are phenotypically distinct from PGE1 independent cells. Furthermore these observations are consistent with the hypothesis that PGE1 increases MDCK cell growth and expression of differentiated function by different mechanisms.
Impact of Health Literacy on Longitudinal Asthma Outcomes

The term health literacy has been used to describe the ability to read and comprehend medical information.1 Such skills may impact all aspects of medical care. In particular, multiple studies carried out in different countries provide evidence that patients with less health literacy have worse health outcomes.2,3 Some of the main outcomes considered were resource utilization and markers of disease control.4,5 In addition, it is possible that health literacy may not only act directly on outcomes, but also may exert its effects through other variables. Thus, the true impact of health literacy may not be appreciated unless a detailed analysis of its effects on other known determinants of outcome is carried out. For example, for patients with asthma, inadequate health literacy may prevent acquisition of asthma knowledge and self-efficacy, and may lead to less effective asthma self-management.6,7 All these variables are well-known determinants of long-term asthma outcomes8,9 and the possible impact of health literacy on these variables is not known. The goals of this analysis were to measure the association between health literacy and longitudinal outcomes in a cohort of asthma patients, and to assess the relationship between health literacy and other variables that are independently related to outcomes.
Solid angle subtended by a circular cylinder

Abstract The solid angle subtended at a point by the lateral surface of a right circular cylinder is approximated by replacing the cylinder surface area seen from the point by a regular polygonal cylindrical surface. This approximation combined with a similar approximation for the solid angle subtended by a circular disc, enables the calculation of the total solid angle from a right circular cylinder to any desired degree of accuracy.
Soliton stability in multimode fibers

We study numerically stability of optical solitons in few-mode fibers. While a single fundamental soliton propagating in any fiber mode is stable, simultaneous propagation of multiple solitons becomes unstable under certain conditions.
Through-Space Charge Transfer and Nonlinear Optical Properties of Substituted Paracyclophane

The introduction, within a π-conjugated donor−acceptor molecule, of an intermediate barrier to electron tunneling and its size scaling and influence on electronic polarization properties have remai...
Large-scale synthesis of arrays of high-aspect-ratio rigid vertically aligned carbon nanofibres

We report on techniques for catalytic synthesis of rigid, high-aspect-ratio, vertically aligned carbon nanofibres by dc plasma enhanced chemical vapour deposition that are tailored for applications that require arrays of individual fibres that feature long fibre lengths (up to 20 µm) such as scanning probe microscopy, penetrant cell and tissue probing arrays and mechanical insertion approaches for gene delivery to cell cultures. We demonstrate that the definition of catalyst nanoparticles is the critical step that enables growth of individual, long-length fibres and discuss methods for catalyst particle preparation that allow the growth of individual isolated nanofibres from catalyst dots with diameters as large as 500 nm. This development enables photolithographic definition of catalyst and therefore the inexpensive, large-scale production of such arrays.
Electrical properties of high-temperature oxides, borides, carbides, and nitrides

High-temperature materials including oxides, borides, carbides, and nitrides encompass all types of conductors: metallic, semiconducting, and ionic. Their electrical conductivities are generally very sensitive to impurities regardless of the type of conductor. For large band-gap materials, which includes most of the oxides, the conductivities at low temperatures are frequently dominated by impurities or dopants, and intrinsic conduction only becomes significant above a temperature which depends largely on the level of dopant, the band gap and the defect structure of the base material. The borides, carbides, and nitrides of transition metals are metallic conductors with conductivities and temperature coefficients of resistivity comparable to that of their parent metals.
Performance of DS-CDMA protocols in wireless LANs

The performance of direct-sequence code-division multiple access (DS-CDMA) systems in indoor wireless channels is presented. TCP traffic, channel noise and signal characteristics are measured using commercial products that implement the IEEE 802.11b DS-CDMA standard. The measured throughputs for a low density mobile network are typically around 4.2 Mbps when one of the two end-systems is on the wired segment. Multipath interference is shown to contribute to significant degradation in TCP performance. Packet loss rates ranging from 0.02 to 0.2 percent are observed in line-of-sight conditions. The BER performance of DS-CDMA is estimated using an image source based channel model of the rectangular room to compute the spatial variation of the channel impulse response. These impulse responses provide a quantitative measure of the system performance and provide estimates of signal power levels required for supporting high data rates in channels influenced by multipath interference.
High Spatial Resolution Observations of a Hot Region in a Solar Flare with the Transition Region and Coronal Explorer

The Transition Region and Coronal Explorer (TRACE) provides some of the highest spatial resolution images ever taken of hot solar flare plasma. The TRACE 195 A channel is particularly sensitive to high-temperature flare plasma because of the presence of the Fe XXIV λ192 resonance line in this bandpass. The TRACE 171 A channel observes emission from thermal bremsstrahlung during a flare. Since this emission is generally weak, it is usually not possible to derive electron temperatures for flare plasma from TRACE observations. In this Letter, we present analysis of the 2000 March 24 X1.8 limb flare that produced high count rates in both the TRACE 195 and 171 A channels. We find evidence for a small, high-temperature region near the top of the flare arcade. This hot region appears to lie at the base of the cusp-shaped structure that extends above the arcade. The TRACE observations are consistent with a strong enrichment of Fe over its photospheric value in the hot region that suggests in situ heating of this plasma. We also find that multithermal simulations of flare evolution reproduce the observations much better than an isothermal model does.
ANAEROBIC METABOLIC RESPONSES TO ACUTE MAXIMAL EXERCISE IN MALE ATHLETES.

Abstract 1. 1. Anaerobic responses to acute maximal exercise were studied in 32 physically trained men by serial changes in concentrations of blood lactate and pyruvate. 2. 2. Excess lactate averaged from 7.9 to 10.7 mM. per liter with different types of maximal exercise; accordingly, the estimated relative contribution of anaerobic metabolism to total metabolic responses ranged from 20 to 28 per cent. 3. 3. It was concluded that a major difference between normal subjects and patients in heart failure is primarily a quantitative difference in circulatory capacity for oxygen transport during exercise, and any difference in mechanisms of energy supply secondary to this limitation of transport is also dependent upon the type, severity, and duration of exertion.
An Energetically Structured Model of Mammalian Cell Metabolism. 1. Model Development and Application to Steady-State Hybridoma Cell Growth in Continuous Culture

Incomplete understanding of mammalian cell culture kinetics hinders the ability of the biochemical engineer or biologist to design and control mammalian cell culture systems and to develop operating strategies. To address this problem, a mechanistic, structured mathematical model has been developed to simulate mammalian cell culture kinetics under a variety of bioreactor operating conditions. An important feature of in vitro mammalian cell metabolism in conventional cell culture media is the partial substitutability of the substrates glucose and glutamine for provision of energy in the cell. The utilization of glucose and glutamine by cells can therefore vary substantially, and these changes can profoundly affect the culture behavior. The model developed here specifically addresses the dynamics of substrate consumption and energy metabolism in mammalian cell culture. This energetically structured (ES) model is also distinguished by the consideration of changes in the specific cell mass with specific growth rate and the consideration of essential amino acids as potentially growth rate limiting. The model is applied here to simulate literature data on the growth and metabolism of a murine hybridoma in continuous culture.
2MASSW J0746425+200322: Is the Secondary a Star or Brown Dwarf?

2MASSW J0746425+200322 is the first L dwarf system with a dynamical mass determination. It has been claimed that the system is young (<500 Myr) and that therefore the secondary is clearly substellar. We argue that the balance of evidence suggests the system is old; the secondary is likely either a star or a long-lived transition object.
AVIAN NEUROHYPOPHYSIAL HORMONES: PHARMACOLOGICAL PROPERTIES AND TENTATIVE IDENTIFICATION

The pattern of pharmacological activities in the chicken ncurohypophysis has been studied and described. These activities correspond to those of a mixture of oxytocin and arginine vasotocin, an analogue of oxytocin synthesized by Katsoyannis and du Vigneaud. Paper chromatographic and enzymatic studies, together with the demonstration of inactivation by thioglycollatc, furnish additional evidence suggesting that oxytocin and arginine vasotocin may be neurohypophysial hormones in the chicken, Gallus domesticus.
Depression among caregivers of children with asthma and its impact on communication with health care providers

Summary Background Caregiver depression is common, can negatively influence one's ability to communicate with health care providers, and may hinder appropriate care for children with asthma. Objective To evaluate the impact of caregiver depression on communication and self-efficacy in interactions about asthma with their child's physician. Study design Cross sectional analysis using data from the Prompting Asthma Intervention in Rochester–Uniting Parents and Providers study. Methods We enrolled caregivers of children (2–12 yrs) with persistent asthma prior to their health care visit. Caregivers were interviewed via telephone after the visit to assess depression, self-efficacy, and provider communication at the visit. Caregiver depression was measured using the Kessler Psychological Distress scale. We assessed caregiver self-efficacy using items from the Perceived Efficacy in Patient–Physician Interactions scale; caregivers rated their confidence for each item (range 0–10). We also inquired about how well the provider communicated regarding the child's asthma care. Bivariate and multivariate analyses were used. Results We interviewed 195 caregivers (response rate 78%; 41% Black, 37% Hispanic), and 30% had depressive symptoms. Caregiver rating of provider communication did not differ by depression. Most caregivers reported high self-efficacy in their interactions with providers; however depressed caregivers had lower scores (8.7 vs. 9.4, p = .001) than non-depressed caregivers. Further, depressed caregivers were less likely to be satisfied with the visit (66% vs. 83%, p = .014), and to feel all of their needs were met (66% vs. 85%, p = .007). In multivariate analyses, depressed caregivers were >2× more likely to be unsatisfied with the visit and to have unmet needs compared to non-depressed caregivers. Conclusions Depressed caregivers of children with asthma report lower confidence in interactions with providers about asthma and are less likely to feel that their needs are met at a visit. Further study is needed to determine the best methods to communicate with and meet the needs of these caregivers.
3′ processing of eukaryotic precursor tRNAs

Biogenesis of eukaryotic tRNAs requires transcription by RNA polymerase III and subsequent processing. 5' processing of precursor tRNA occurs by a single mechanism, cleavage by RNase P, and usually occurs before 3' processing although some conditions allow observation of the 3'-first pathway. 3' processing is relatively complex and is the focus of this review. Precursor RNA 3'-end formation begins with pol III termination generating a variable length 3'-oligo(U) tract that represents an underappreciated and previously unreviewed determinant of processing. Evidence that the pol III-intrinsic 3'exonuclease activity mediated by Rpc11p affects 3'oligo(U) length is reviewed. In addition to multiple 3' nucleases, precursor tRNA(pre-tRNA) processing involves La and Lsm, distinct oligo(U)-binding proteins with proposed chaperone activities. 3' processing is performed by the endonuclease RNase Z or the exonuclease Rex1p (possibly others) along alternate pathways conditional on La. We review a Schizosaccharomyces pombe tRNA reporter system that has been used to distinguish two chaperone activities of La protein to its two conserved RNA binding motifs. Pre-tRNAs with structural impairments are degraded by a nuclear surveillance system that mediates polyadenylation by the TRAMP complex followed by 3'-digestion by the nuclear exosome which appears to compete with 3' processing. We also try to reconcile limited data on pre-tRNA processing and Lsm proteins which largely affect precursors but not mature tRNAs.A pathway is proposed in which 3' oligo(U) length is a primary determinant of La binding with subsequent steps distinguished by 3'-endo versus exo nucleases,chaperone activities, and nuclear surveillance.
Non‐epithelial tumors of the nasal cavity, paranasal sinuses and nasopharynx. A clinicopathologic study. VIII. Adipose tissue tumors (lipoma and liposarcoma)

In a study of 256 non-epithelial neoplasms involving the nasal cavity, paranasal sinuses and nasopharynx, only two lesions were classified as adipose tissue tumors (one lipoma and one liposarcoma). The lipoma was found incidentally when tissue removed from the maxillary sinus was studied histologically, the patient having been treated with a Caldwell-Luc procedure for maxillary sinusitis. The liposarcoma produced a large mass involving the nasal cavity, maxillary sinus, ethmoid area, hard palate and maxillary, temporal and sphenoid bones. The tumor extended into the cranial cavity and eventually led to the patient's death. The problems involved in histologically differentiating liposarcomas from other lesions are discussed. Even though adipose tissue tumors are among the most common soft tissue neoplasms, these lesions rarely occur in the nasal cavity, paranasal sinuses and nasopharynx.
Bcl-2 maintains B cell memory

The number of lymphocytes in an animal is remarkably constant despite antigen-driven proliferation and a high rate of B-cell lymphopoiesis. This reflects the relatively brief lifespan of many newly generated B cells and argues for a well-regulated death mechanism. Even so, a secondary immune response can be generated years after a primary exposure to antigen. Antigen that might restimulate B cells persists for extended periods on follicular dendritic cells in the light zone of germinal centres. Antigen-binding B cells have also been found months after the end of obvious cell division. The precise signal that enables certain B cells to emerge as long-term surviving memory cells is unknown. Bcl-2, an inner mitochondrial membrane protein, blocks programmed cell death in B cells. We report here that this proto-oncogene maintains immune responsiveness. Transgenic mice overproducing Bcl-2 have a long-term persistence of immunoglobulin-secreting cells and an extended lifetime for memory B cells.
Targeting Techniques for Enhancing Process Yield

A hierarchical procedure is developed to identify maximum targets for the overall yield of the process. First, we identify the key causes for loss in overall process yield. Then, several mass integration strategies are proposed to attain maximum yield. These include rerouting of raw materials, optimization of reaction yield, rerouting of product from undesirable outlets to desirable outlets, and recycle of unreacted raw materials. Path equations are tailored to provide the appropriate level of details for modelling the process performance as a function of the optimization variables pertaining to design and operating variables. Interval analysis is used as an inclusion technique that provides rigorous bounds regardless of the process nonlinearities. The proposed procedure is systematic, rigorous, and computationally efficient. A case study is used to illustrate the applicability of the proposed procedure.
Factors influencing mutual gaze in captive female Japanese monkeys (Macaca fuscata)

Mutual gaze occurs when two animals simultaneously look at each other, and therefore signals reciprocal visual attention. We studied the occurrence of mutual gaze among adult female Japanese monkeys (Macaca fuscata) housed at the Central Park Zoo in New York City (USA). We found that the frequency of mutual gaze varied according to one aspect of social context (proximity), and that monkeys’ age-rank was negatively correlated with the frequency of mutual gaze. The behavioral contexts in which mutual gaze was observed did not include aggression, and social rank did not predict frequency of mutual gaze. Mutual gaze therefore varies according to some aspects of social context and is generally predicted by factors that influence other social behaviors (e.g., age).
Influence of phosphorus level on VA Mycorrhizal colonization and growth of cowpea cultivars

Vesicular-arbuscular mycorrhizal (VAM) associations often vary according to the abundance of available soil phosphorus (P). Therefore, understanding the response of crop plants to colonization by VAM fungi necessitates the study of the response of colonized and noncolonized plants, from a range of cultivars, to differing levels of P. Cowpea is grown throughout the world, often on impoverished soils in which it can benefit from formation of mycorrhizae. The present study was conducted to determine the response of four cultivars of cowpea (Vigna unguiculata (L.) Walp.), varying in nitrogen fixation capacity, to inoculation withGlomus fasciculatum at four levels of added P in the rooting medium. In a greenhouse experiment, four cowpea cultivars, Mississippi Silver, Brown Crowder, Six Week Browneye and MI 35, were grown with and without the mycorrhizal fungus at four levels of added P, 0, 10, 20 and 30 ppm. Root colonization (%) was negatively correlated with P content of the growth medium and shoot P concentration. Intraspecific variability was shown for shoot dry weight and leaf area in response to inoculation withG. fasciculatum at different P levels. The range of P required in the growth medium which allowed benefit fromG. fasciculatum was identified for individual cultivars using shoot dry weight and leaf area, and collectively across cultivars for other parameters.
Caring for a Family Member With Cancer: Past Communal Behavior and Affective Reactions1

An important recent development in the caregiving literature is an increased focus on the role played by the interpersonal relationship between caregiver and care recipient. In this study, a prediction derived from communal relationship theory (Clark & Mills, 1979, 1993; Mills & Clark, 1982) was tested in a sample of patients with recurrent cancer and their family caregivers. Specifically, it was hypothesized that if a relationship had been communal in the past (i.e., characterized by mutual demonstrations of concern for and responsiveness to one another's needs), positive feelings about helping one's partner should continue even when one partner's needs far outweigh those of the other. Consistent with this hypothesis, results indicated that caregivers whose relationship with the patient before illness onset had been characterized by relatively infrequent communal behaviors evidenced more symptoms of depression that did those whose relationship had been characterized by more frequent communal behaviors. In addition, the effects of prior communal behavior on depressed affect were both mediated and moderated by feelings of burden. Caregivers who recalled relatively few communal behaviors in their past relationship felt more burdened by their caregiving role, and burden in turn predicted greater depressive symptomatology. Implications for early identification of caregivers at risk for becoming distressed are discussed.
Parent–Child Interaction Therapy: A Meta-Analysis of Child Behavior Outcomes and Parent Stress

Parent–Child Interaction Therapy (PCIT) is a behavioral family therapy approach that aims to establish a parent–child relationship that will enable parents to teach their preschool-age child prosocial skills, leading to a decrease in inappropriate and maladaptive behaviors. The purpose of this article is to review recent research on PCIT and conduct a meta-analysis to evaluate the effectiveness of this parenting intervention as reported in 11 studies that met criteria for involvement. In addition to child behavior, this meta-analysis focuses on parenting stress as a primary outcome of interest. The authors found an emphasis on effectiveness, dissemination, and portability to diverse populations in our review of PCIT outcome studies from 2004 to 2011. Implications for practice, policy, and research are addressed.
PC‐Based Traffic Accident Data Analysis Program

A menu-oriented microcomputer database package has been developed to record and analyze traffic accident data in a small- to medium-sized jurisdiction. Designed primarily for the traffic engineer, the package was developed during a microcomputer software development project funded by the FHWA Rural Technical Assistance Program. The program runs under MS-DOS on IBM PC compatible machines, and requires dBase III or III Plus. KSLAD accepts up to 59 data items from each accident report, nine of which can be defined by the user to meet any particular need. The database can be used with any accident report form, because the allowable values of coded data fields may be altered by the user. Output consists of summary reports based on location or accident characteristic criteria specified by the user, or for the entire data set; a high accident location analysis procedure is also included. The program provides a starting point for the evaluation and correction of high accident locations.
A High Gain, Composite Nd:YVO4/SiC Thin Disk Amplifier

We have demonstrated a new form of Nd:YVO4 amplifier operating at 1064 nm based on a 800 µm thick Nd:YVO4 gain layer bonded to a 4H-SiC prism. The amplifier was tested in the ‘master oscillator - power amplifier’ (MOPA) configuration, where both the seed source and the single pass amplifier were operated in a quasi-continuous wave (Q-CW) regime: pulse duration 500 µs, pulse repetition frequency (PRF) - 100 Hz. The Nd:YVO4gain element was pumped by a 808 nm laser diode bar stack to amplify seed inputs in the power range of 1 to 55 W with a gains of 4 to 2.6, respectively, with 25% optical-to-optical extraction efficiency. The temperature distribution of the gain medium was measured under operational conditions using thermography.
On maximum likelihood solutions for exponential survival models

Stochastic survival models which adjust for covariate information have been developed by Beck (1979). These models can include one or two living states and several competing death states. The transitions between stages are assumed irreversible and the transition intensity functions are assumed to be independent of time but dependent upon the covariates. Explicit solutions of the maximum likelihood equations for such models when there are one or two dichotomous covariates are presented. Applications of these models to the case of heart transplants and lung cancer are discussed and survival in two or four groups is compared. (summary in FRE) (EXCERPT)
Comment on “Particle-number-conserving Bogoliubov method which demonstrates the validity of the time-dependent Gross-Pitaevskii equation for a highly condensed Bose gas”

A recent paper of Gardiner [Phys. Rev. A 56, 1414 (1997)] introduces a particle-number-conserving Bogoliubov method for the excitation spectrum of a Bose-condensed gas, for use in theories of recently experimentally produced trapped atomic Bose condensates. Gardiner's approach is compared and contrasted with the 1959 Girardeau-Arnowitt theory [Phys. Rev. 113, 755 (1959)], to which it is closely related and which is also fully number conserving. The number-conserving Bogoliubov quasiparticle operators of the Girardeau-Arnowitt theory satisfy Bose commutation relations exactly so long as states with the condensate totally depleted are neglected, whereas those of Gardiner satisfy Bose commutation relations only in an approximation that deteriorates progressively as the condensate is depleted.
Identification of Two Quorum-Sensing Systems in Sinorhizobium meliloti

Sinorhizobium meliloti is a free-living soil bacterium which is capable of establishing a symbiotic relationship with the alfalfa plant (Medicago sativa). This symbiosis involves a network of bacterium-host signaling, as well as the potential for bacterium-bacterium communication, such as quorum sensing. In this study, we characterized the production of N-acyl homoserine lactones (AHLs) by two commonly used S. meliloti strains, AK631 and Rm1021. We found that AK631 produces at least nine different AHLs, while Rm1021 produces only a subset of these molecules. To address the difference in AHL patterns between the strains, we developed a novel screening method to identify the genes affecting AHL synthesis. With this screening method, chromosomal groEL (groELc) was shown to be required for synthesis of the AHLs that are unique to AK631 but not for synthesis of the AHLs that are made by both AK631 and Rm1021. We then used the screening procedure to identify a mutation in a gene homologous to traM of Agrobacterium tumefaciens, which was able to suppress the phenotype of the groELc mutation. A traR homolog was identified immediately upstream of traM, and we propose that its gene product requires a functional groELc for activity and is also responsible for inducing the synthesis of the AHLs that are unique to AK631. We show that the traR/traM locus is part of a quorum-sensing system unique to AK631 and propose that this locus is involved in regulating conjugal plasmid transfer. We also present evidence for the existence of a second quorum-sensing system, sinR/sinI, which is present in both AK631 and Rm1021.
Integra® dermal regenerative template application on exposed tendon

Background Tendon without paratenon presents the reconstructive surgeon with a tissue coverage challenge. Integra® dermal regenerative template has been shown to initiate a stable, vascularized bed for skin grafting over tendon. However, histological processes that occur during incorporation have not been described. The purpose of this study is to characterize the pattern of changes that occur when Integra® is applied to an avascular tendon. We hypothesize that vascular incorporation will originate from the wound periphery and proceed toward the tendon center.
On reasoning from data

Our society is currently entering a new phase in which gigabytes of’ information are becoming readily available for exploration over academic networks, digital libraries, and commercial information services as well as in proprietary commercial and governmental databases. This important technological development presents a substantial challenge, as future intelligent systems must be able to store very large streams of data, summarize and index this data using concise and efficient models, and subsequently perform very efficient retrieval and reasoning in response to real-time queries and updates. We informally refer to this challenging task as reasoning from data. Most previous AI research and applications have concentrated on relatively simple operations, for example, highly constrained queries on relatively static, immutable systems of knowledge such as mathematics, chess, and hardware components inventories, where it is possible to abstract rules that can be viewed as true and valid. There are many other domains in which data changes more or less rapidly and in which abstract truths are at best temporary or contingent, for example, robot environments, software environments, demographic databases and public-health data, ecological and economics (ecosystems, chemical processes, marketing and point-of-sale databases, financial time series, and video and text databases. In addition, these domains are associated with a demand for very fast response to unanticipated queries and continuous updates over uncertain, dynamic, interactive, and rapidly changing environments. These domains present a challenge for purely symbolic, rule-based approaches to AI. For instance, it appears to be difficult to give a formal logical specification of concepts such as an important electronic message, a fair scheduler, an urgent phone call, a good travel package to Hawaii, an intriguing new paper about Bayesian reasoning, a high-risk car, a good real-estate investment, or an interesting economic trend. Statistical decision theory [Pearl 1988] provides a useful framework to model adaptive intelligent agents in stochastic and rapidly evolving domains. Moreover, it provides precise criteria (loss functions, expected utility) to evaluate the performance of such agents. i30wever, when the environment is large, the process of fitting good models (finding maximum u posterior models or even maximum likelihood models) to data generated by the environment is typically computationally intractable. When the envwonment is small, we often have trouble getting sufficient statistics. Thus the models we can devise effectively are rarely accurate, regardless of the size of
Controlling cell geometry on substrates of variable stiffness can tune the degree of osteogenesis in human mesenchymal stem cells

The physical properties of the extracellular matrix (ECM) play an important role in regulating tissue-specific human mesenchymal stem cell (MSC) differentiation. Protein-coated hydrogels with tunable stiffness have been shown to influence lineage specific gene expression in MSCs. In addition, the control of cell shape - either through changing substrate stiffness or restricting spreading with micropatterning - has proved to be important in guiding the differentiation of MSCs. However, few studies have explored the interplay between these physical cues during MSC lineage specification. Here, we demonstrate geometric control of osteogenesis in MSCs cultured on micropatterned polyacrylamide gels. Cells cultured on fibronectin-coated gels express markers associated with osteogenesis in a stiffness dependent fashion with a maximum at ~30kPa. Controlling the geometry of single cells across the substrate demonstrates elevated osteogenesis when cells are confined to shapes that promote increased cytoskeletal tension. Patterning MSCs across hydrogels of variable stiffness will enable the exploration of the interplay between these physical cues and their relationship with the mechanochemical signals that guide stem cell fate decisions.