cssi/SciSciGPT-SciSciNet huggingface dataset:
VT-BEST: Shaping biomedical professional development programming across colleges and campuses

Abstract When the NIH BEST awards were introduced in 2013, Virginia Tech had recently entered a new phase of growth in the biomedical and health sciences, with the establishment of its health sciences campus, medical school, and biomedical research institute, as well as new interdisciplinary research training programs that were under way. The award came at a propitious time for shaping this evolving training environment for graduate students and postdocs across the university, by facilitating the creation of novel experiential learning opportunities, collaboratives to develop and test creative new curricular elements, and a framework for sustainability. In this chapter we discuss how Virginia Tech's structure and community influenced our VT-BEST program design and implementation. We also overview our key program components, and discuss some challenges and insights gained over the course of the BEST experiment.
HDAC3 regulates senescence and lineage-specific transcriptional programs in non-small cell lung cancer

Transcriptional deregulation is a common feature of many cancers, which is often accompanied by changes in epigenetic controls. These findings have led to the development of therapeutic agents aimed at broad modulation and reprogramming of transcription in a variety of cancers. Histone Deacetylase 3, HDAC3, is one of the main targets of HDAC inhibitors currently in clinical development as cancer therapies, yet the in vivo role of HDAC3 in solid tumors is unknown. Here, we define the role of HDAC3 in two genetic engineered models of the most common subtypes of Kras-driven Non-Small Cell Lung Cancer (NSCLC), KrasG12D, STK11-/- (KL) and KrasG12D, p53-/- (KP), where we found that HDAC3 is strongly required for tumor growth of both genotypes in vivo. Transcriptional profiling and mechanistic studies revealed that HDAC3 represses p65 RelA/NF-kB-mediated induction of the Senescence Associated Secretory Program (SASP). Additionally, HDAC3 was found to cooperate with the lung cancer lineage transcription factor NKX2-1 to mediate expression of a common set of target genes. Leveraging observations about one HDAC3/NKX2-1 common target, FGFR1, we identified that an HDAC3-dependent transcriptional cassette becomes hyperactivated as Kras mutant cancer cells develop resistance to the MEK inhibitor Trametinib, and this can be rescued by treatment with the Class I HDAC inhibitor Entinostat. These unexpected findings reveal new roles for HDAC3 in proliferation control in tumors in vivo and identify specific therapeutic contexts for the utilization of HDAC3 inhibitors, whose ability to mechanistically induce SASP may be harnessed therapeutically.
Real-time measurements of fluorescent aerosol particles in a living laboratory office under variable human occupancy and ventilation conditions

Abstract The abundance of super-micron biological and abiotic particles in occupied indoor environments can be influenced by time-dependent changes in human-associated emissions and building ventilation conditions. Real-time measurements of fluorescent aerosol particles (FAPs) were integrated with a building sensing platform to evaluate the influence of human occupancy and ventilation on the temporal dynamics of fluorescent biological and abiotic particles in a living laboratory office. Concentrations and size distributions of FAPs were measured via laser-induced fluorescence (LIF). Human occupants were identified as a major source of super-micron FAPs in mechanically ventilated office buildings. Mass concentrations and size distributions of FAPs larger than 3 μm scaled with human occupancy in the office. Detailed single particle fluorescence data indicated that human-associated emissions enriched the office atmosphere with specific FAP types that varied in morphology. Office occupants were strong emitters of ABC-type particles (number and mass), and to a lesser extent, A-type particles (number and mass), AB-type particles (mass), and B-type particles (mass). Such FAP types are related to common indoor bacterial and fungal aerosols and fluorescent clothing fabric fibers. The introduction of natural ventilation via a double skin glass facade increased the indoor abundance of FAPs due to the efficient transport of outdoor FAPs into the office. While LIF provides valuable real-time data on indoor FAP dynamics, it lacks specificity and cannot fully resolve the origins of fluorescent biological and abiotic particles in indoor spaces.
Non-linear Archetypal Analysis of Single-cell RNA-seq Data by Deep Autoencoders

Advances in single-cell RNA sequencing (scRNA-seq) have led to successes in discovering novel cell types and understanding cellular heterogeneity among complex cell populations through cluster analysis. However, cluster analysis is not able to reveal continuous spectrum of states and underlying gene expression programs (GEPs) shared across cell types. We introduce scAAnet, an autoencoder for single-cell non-linear archetypal analysis, to identify GEPs and infer the relative activity of each GEP across cells. We use a count distribution-based loss term to account for the sparsity and overdispersion of the raw count data and add an archetypal constraint to the loss function of scAAnet. We first show that scAAnet outperforms existing methods for archetypal analysis across different metrics through simulations. We then demonstrate the ability of scAAnet to extract biologically meaningful GEPs using publicly available scRNA-seq datasets including a pancreatic islet dataset, a lung idiopathic pulmonary fibrosis dataset and a prefrontal cortex dataset.
A Study of Exploring Different Schedules of Spacing and Retrieval Interval on Mathematics Skills in ITS Environment

The present study was designed to help answer several questions regarding the impact of spacing and expanding retrieval practice on mathematics skills. For this study, we set up four different interval schedules (1 day; 4 days; 7 days; 14 days) in an ITS environment, and examined the impact on retention performance by comparing results across groups. There were significant performance differences on different groups of students, and all fours groups of students showed small declines in the retention performance with longer intervals. Furthermore, we examined students with high-, medium-, and low-knowledge of skills, and found a strong effect on retention performance with the basis of initial performance on skills. In addition, students with weaker knowledge showed a much more rapid forgetting than students with higher knowledge. These results suggest retention intervals should probably not be fixed, but should vary based on the student’s knowledge of the skill.
The Titan Wind Tunnel: A new tool for investigating extraterrestrial aeolian environments

Abstract Aeolian processes occur throughout the Solar System and likely on extrasolar planets as well. Models based on data collected in boundary layer wind tunnels have contributed to understanding the physics of these processes. Planetary wind tunnels allow simulation of conditions (atmospheric pressure, density, or kinematic viscosity) on extraterrestrial bodies, and their use over several decades has demonstrated important differences between terrestrial and extraterrestrial aeolian processes. A high-pressure wind tunnel is now available in the Planetary Aeolian Laboratory (PAL) at the NASA Ames Research Center. Used up to the early 1990’s for Venus analog experiments, this wind tunnel has been refurbished and is now in use as the Titan Wind Tunnel (TWT) for Titan analog experiments. Initial results for threshold friction wind speeds at Titan analog conditions do not agree with models based on experimental data at terrestrial, Martian, and Venusian analog conditions (Burr et al., 2015). These results from the TWT work continue a history of wind tunnel experiments that show repeated under-prediction of threshold by models based on non-analog conditions. In addition to suggesting caution in extrapolating from one surface environment to another, this historical record highlights the utility of experiments in wind tunnels that provide closely analogous conditions to the environment of interest. The TWT, along with other PAL facilities, provides the means for further analog experiments by the scientific community to support continued advancement in understanding planetary aeolian processes.
Carcinoma of the thyroid in children and young adults: iatrogenic relation to previous irradiation.

Fifteen cases of carcinoma of the thyroid and four cases of thyroid adenoma in children and young adults are reported. In all, except one, irradiation had been given to the head, neck, or chest of these patients 5 to 17 years previously. These observations suggest that carcinoma of the thyroid in children is related to irradiation, often prescribed for uncertain therapeutic effect. Irradiation to the head, neck, or chest of infants and children should be avoided wherever possible. We believe these cases represent a remarkably high incidence of thyroid neoplasia to occur in a single practicing pediatric office. The practicing pediatrician who now follows his patients longitudinally from infancy through adolescence has a unique opportunity to observe the development of disease, even years later.
Wild-type gas vesicle formation requires at least ten genes in the gvp gene cluster of Halobacterium halobium plasmid pNRC100.

Abstract To study the functions of the 13 gvp genes, gvpMLKJIHGFEDACN, on plasmid pNRC100 of Halobacterium halobium in gas vesicle formation, we carried out linker scanning mutagenesis of the gene cluster. We constructed a 24.5-kb Escherichia coli-H. halobium shuttle plasmid, pFL2, containing the gvp gene cluster and introduced a kanamycin resistance (kappa) cassette into each gene (except for gvpA). Transformation of H. halobium SD109, which had the entire gvp gene cluster deleted, with pFL2 and mutated pFL2 derivatives showed that while the unmutated gene cluster successfully programmed gas vesicle formation, derivatives with insertion of the kappa cassette in any of the gvp genes, except gvpM, did not lead to production of normal gas vesicles. Insertions in gvpL, -K, -J, -I, and -F resulted in a complete block in gas vesicle synthesis, while insertions in gvpH, -G, -E, -D, -C, and -N resulted in greatly reduced gas vesicle synthesis. In most cases, the block in gas vesicle synthesis did not result from polar effects, since similar results were obtained for derivatives of the insertion mutants in which most of the internal portion of the kappa cassette was deleted and only small (15 to 54-bp) insertions remained. The only exceptions were for gvpH and gvpD, where deletion of the internal portion of the kappa insertions resulted in phenotypic reversion. Electron microscopic analysis of the kappa mutants revealed that interruptions of gvpC and gvpN result in the formation of smaller gas vesicle than in the wild type, while interruptions of gvpF, -G, -H, -J, -K, and -L produce no discernible vesicle intermediates. These results indicate the gvpA, -C, and -N, which have the rightward transcriptional orientation, encode structural proteins, with gvpC and gvpN necessary for late stages of vesicle formation, and gvpL, -K, -J, -I, -H, -G, and -F, which have the leftward transcriptional orientation encode proteins involved in early steps in the assembly of gas vesicles.
Tertiary and quaternary structure of tobacco mosaic virus and protein. I. Effect of pH on fluorescence and 2-p-toluidinylnaphthalene-6-sulfonate binding.

Abstract Tobacco mosaic virus and its protein exhibit pH-dependent changes in their wavelength and intensity of maximum emission, λ max,pro and I pro , respectively. The binding of 2-p- toluidinylnaphthalene-6-sulfonate (TNS) to tobacco mosaic virus protein or tobacco mosaic virus produces a strong increase in its fluorescence intensity, I TNS . This binding is pH dependent. The protein is severely denatured at pH >; 10.5 or as indicated by large increases in λ max,pro . Strong increases in I TNS occur concomitantly with these increases in λ max,pro , indicating increased binding of TNS upon denaturation. Presumably hydrophobic sites, exposed on denaturation, provide effective binding sites for TNS. Heat denaturation of tobacco mosaic virus protein at pH 7 led to similar increases in λ max,pro and I TNS . In the pH range where aggregation of the protein occurs, pH 6–7, λ max,pro remains constant and only minor changes in I pro and I TNS occur. Major conformational changes do not appear to accompany aggregation. No significant changes in λ max,pro , I pro and I TNS occur between pH 6 and 7 when the native virus is titrated. The changes in I pro and I TNS for tobacco mosaic virus protein in this pH range are apparently associated with the aggregation of the protein. TNS is bound more weakly to the virus than to the protein at all pH values.
PERFORMANCE IMBALANCES IN THE CHAIN: EU TRADITIONAL FOOD SECTOR

Abstract Organizations nowadays no longer compete as independent entities, but as chains (Christopher, 1998, Cox, 1999, Lambert and Cooper, 2000). Hence, being part of a well-performing chain is crucial for the future of the individual food firm, especially in the context of the globalizing economy. As a result, understanding differences between low, medium and high performing chains is essential for the different chain members. The objective of this study is to measure and to identify the main determinants of traditional food chain performance. Therefore, quantitative data were collected via individual interviews with 271 chain members (91 suppliers, 91 focal companies and 89 customers) of 91 traditional food chains from three European countries (Belgium, Italy and Hungary), representing six different traditional food product categories (cheese, beer, ham, sausage, white pepper and bakery). The results differentiate six different kinds of chain imbalances, namely: dyadic upper and lower, up- and downstream, internal and external indicate both dyadic and chain-wise imbalance. Most chain imbalances are noticed in relation to lowering logistic costs and to reducing lead time. Further, the most discriminating determinant of low, medium and high performing chains is chain reputation. Governance structures although do not reveal any significant difference. These results are valid across member states, across product categories and across different sized chains. Future research should investigate whether the well-performing chains generate a sustainable competitive advantage over time. In addition, performance indicators can be enlarged with parameters other than economical ones such as ecological and social ones.
Extreme Periodontal Disease in a Brazilian Free-Tailed Bat (Molossidae: Tadarida brasiliensis) from Eastern Texas

Abstract A male Brazilian free-tailed bat (Tadarida brasiliensis), collected from a colony in Huntsville, Walker County, Texas, had severe periodontal disease resulting in extensive loss of teeth. Although demonstrating normal activity and a healthy appearance, this individual had only eight teeth: normal complement is 30–32 teeth. The remaining teeth appeared to be sufficient for this individual to adequately process food and maintain an average body weight as reported for this species.
The adaptive decision maker: Studying contingent decisions: An integrated methodology

Introduction The preceding chapter offered a theoretical framework for understanding how people decide which decision strategy to use in solving a particular judgment or choice problem. We hypothesized that the use of multiple strategies by a decision maker was an adaptive response to decision problems, given that the decision maker had goals for both the accuracy of the decision and for the effort required. A major distinction between our framework and that of several other researchers is the emphasis we place on understanding contingent decision behavior at a detailed information-processing level of explanation. This emphasis on understanding process requires an integrated methodology with two features: the capability to derive specific process level predictions regarding adaptivity in decision processes; and tests of those predictions on detailed, process-tracing data from individuals facing decision problems. We propose and illustrate such an approach in this chapter. Our approach combines the use of simulation of decision processes to make detailed predictions with the use of a computerized system for collecting process-tracing data on information acquisition behavior, which can then be used to test those predictions. This integrated methodology is unique to our work and is at a more detailed level than is typical in most research on decision making. In the next sections we present the components of our methodology. First, we examine how to simulate decision strategies using production systems, discuss some computer simulation results, and consider the predictions for process data that these results imply.
The response of subthalamic nucleus neurons to dopamine receptor stimulation in a rodent model of Parkinson's disease.

Overactivity in the subthalamic nucleus (STN) is believed to contribute to the pathophysiology of Parkinson’s disease. It is hypothesized that dopamine receptor agonists reduce neuronal output from the STN. The present study tests this hypothesis by using in vivo extracellular single unit recording techniques to measure neuronal activity in the STN of rats with 6-hydroxydopamine-induced lesions of the nigrostriatal pathway (a model of Parkinson’s disease). As predicted, firing rates of STN neurons in lesioned rats were tonically elevated under basal conditions and were decreased by the nonselective dopamine receptor agonists apomorphine and l-3,4-dihydroxyphenylalanine (l-DOPA). STN firing rates were also decreased by the D2 receptor agonist quinpirole when administered after the D1 receptor agonist (±)- 1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol (SKF 38393). Results of the present study challenge the prediction that dopaminergic agonists reduce STN activity predominantly through actions at striatal dopamine D2 receptors. Firing rates of STN neurons were not altered by selective stimulation of D2 receptors and were increased by selective stimulation of D1 receptors. Moreover, there was a striking difference between the responses of the STN to D1/D2 receptor stimulation in the lesioned and intact rat; apomorphine inhibited STN firing in the lesioned rat and increased STN firing in the intact rat. These findings support the premise that therapeutic efficacy in the treatment of Parkinson’s disease is associated with a decrease in the activity of the STN, but challenge assumptions about the roles of D1 and D2 receptors in the regulation of neuronal activity of the STN in both the intact and dopamine-depleted states.
The Basis of Authority in Religion

RELIGIONISTS go to two extremes. There are the dogmatists who try to fetter the roving human mind. They are fundamentally fascistic; history teems with illustrations of the evil which they have done. There are also the anarchists; seeing the evils of dogmatism, they reject all authority. The result is confusion. Reactionary Catholics and literalistic Protestants incline toward the first extreme; liberal Protestants are in danger of the second. This writer recalls a student who wrote on an examination: "A Protestant can believe anything that he wishes." No one has a right to believe anything that he wishes; everyone is under obligation to test his beliefs. While Roman Catholicism suffers from excess authority, liberal Protestantism's weakness is lack of authority. Freedom lovers leave the Catholic Church because of its dogmatism. The perplexed leave the Protestant fold because they find little security. Thus the problem of authority is directly related to the basic issues of life. Since our age is chaotic, it is not at all surprising that there is confusion in religion. Yet religion is so important, so vitally related to the destiny of men and of nations that we must not allow confusion to be the last word. If we do disintegration will be the result followed by new forms of authoritarianism. We are forced, therefore, to again consider the basis of authority with the hope of finding some working solution. 2. WAYS THAT HAVE BEEN TRIED
Climate, Race, and Imperial Authority: The Symbolic Landscape of the British Hill Station in India

Abstract Nostalgia for home is quite natural among expatriates. The English country life recreated in the hill stations of India, however, was elaborated on by the greater prestige of an imperial people. This paper examines the hill station as a landscape type tied to nineteenth-century discourses of imperialism and climate. Both discourses serve as evidence of a belief in racial difference and, thereby, the imperial hill station reflected and reinforced a framework of meaning that influenced European views of the non-western world in general. Because the hill station was seen as a resource to be protected for use by the British ruler, the standards used in colonial settlement planning are framed in these discourses of privilege and difference. Primary attention is given to the high imperial age from 1870 to 1914 when construction activity was greatest. Ootacamund, the summer capital of the Madras presidency in southern India, serves as the case study for evaluating this landscape type.
Oral Rotavirus Vaccines: How Well Will They Work Where They Are Needed Most?

Rotavirus vaccines hold promise to decrease the burden of severe diarrhea in the poorest countries, where 85% of deaths due to rotavirus occur. However, the potency of live oral vaccines is lower in these challenging settings than in middle- and upper-income countries. Many hypotheses have been suggested to explain these differences that could provide clues to improve the ultimate success of these novel vaccines. Although introduction today of even moderately effective vaccines will decrease the morbidity and mortality associated with rotavirus in low-income settings, research is urgently needed to understand why these differences in efficacy occur and what could be done to improve vaccine performance to maximize the life-saving benefits of vaccination.
Numerical study of high-area-ratio H2/O2 rocket nozzles

Calculations were made for high-area-ratio H2/O2 rocket nozzles by using the RPLUS code which employs an implicit finite volume, lower-upper symmetric successive over-relaxation scheme to solve the Navier-Stokes equations and the species equations in a coupled manner. The combustion processes of hydrogen and oxygen are modeled by an 8-species and 18-step reaction mechanism, and the turbulence is simulated by the Baldwin-Lomax turbulence model with a pressure gradient correction on the van Driest's damping constant in the inner-layer model. The calculated results for two different rocket nozzles are presented as contours, profiles, and performance values. The predicted specific impulse and thrust agree well with the experimental data and those from the industry standard code. It is demonstrated that the RPLUS code can be used for analysis of rocket nozzles.
Pattern matching in the Hamming distance with thresholds

It has long been known that pattern matching in the Hamming distance metric can be done in O(min(|@S|,m/logm)nlogm) time, where n is the length of the text, m is the length of the pattern, and @S is the alphabet. The classic algorithm for this is due to Abrahamson and Kosaraju. This paper considers the following generalization, motivated by the situation where the entries in the text and pattern are analog, or distorted by additive noise, or imprecisely given for some other reason: in any alignment of the pattern with the text, two aligned symbols a and b contribute +1 to the similarity score if they differ by no more than a given threshold @q, otherwise they contribute zero. We give an O(min(|@S|,m/logm)nlogm) time algorithm for this more general version of the problem; the classic Hamming distance matching problem is the special case of @q=0.
Moderate-Resolution Imaging Spectroradiometer ocean color polarization correction

The polarization correction for the Moderate-Resolution Imaging Spectroradiometer (MODIS) instruments on the Terra and Aqua satellites is described. The focus is on the prelaunch polarization characterization and on the derivation of polarization correction coefficients for the processing of ocean color data. The effect of the polarization correction is demonstrated. The radiances at the top of the atmosphere need to be corrected by as much as 3.2% in the 412 nm band. The effect on the water-leaving radiances can exceed 50%. The polarization correction produces good agreement of the MODIS Aqua water-leaving radiance time series with data from another, independent satellite-based ocean color sensor, the Sea-Viewing Wide Field-of-View Sensor (SeaWiFS).
Management of ischemic stroke: Part 2. The inpatient stay

BACKGROUND: Acute ischemic stroke is commonly encountered by the hospitalist. There have been dramatic changes in our ability to care for these patients both acutely and in secondary prevention. The Joint Commission on Accreditation of Healthcare Organizations (JCAHO) primary stroke center certification has become progressively more important to institutions nationally and emphasizes many elements of the inpatient stay and discharge process. PURPOSE: After admission, the focus changes to avoidance of complications and the appropriate initiation of allied therapies and secondary prevention. DATA SOURCES: Primary trials, current guidelines. CONCLUSIONS: The hospitalist is well-positioned to play a major role in the treatment of stroke patients as well as the systems work that aids in the management of this population. Journal of Hospital Medicine 2010;5:88–93. © 2010 Society of Hospital Medicine.
Field-aligned currents in the polar cap during saturation of the polar cap potential

Abstract During periods of very strong southward magnetic field in the solar wind the polar cap potential becomes saturated. Recent investigations of the saturation of the polar cap potential suggest that the Region 1 current system plays a major role in balancing the solar wind pressure, leading to the saturation effect. To do this, the Region 1 current must flow on open field lines, closing outside Earth magnetosphere, where it can exert a J × B force on the solar wind. In this paper we present observations from DMSP F13 of the low-altitude distribution of field-aligned currents with Region 1 polarity relative to the boundary between open and closed field lines. The observations show that during a period of strongly southward solar wind magnetic field, a substantial amount of field-aligned current was flowing on field lines that had merged with the interplanetary magnetic field. On the other hand, during a period of nominal southward solar wind magnetic field, much less field-aligned current with Region 1 polarity was found in the open field line region. These observations support the view that Region 1 field-aligned currents can play a role in the force balance between the magnetosphere and the solar wind during periods of strongly southward IMF.
Life course transitions in early adulthood and SES disparities in tobacco use

A huge literature has documented adult socioeconomic disparities in smoking but says less about how these disparities emerge over the life course. Building on findings that smoking among adolescents differs only modestly by parental SES, we utilize a life course perspective on social differentiation to help explain the widening disparities in smoking in young adulthood. Our theory suggests that achieved socioeconomic status and the nature and timing of adult role transitions affect age-based trajectories of smoking and widen disparities in adult smoking. The analyses use data from the National Longitudinal Study of Adolescent Health, which follows a representative national sample over four waves from ages 11-17 in 1994/1995 to 26-34 in 2007/2008. The results show divergent age trajectories in smoking by parental education and that achieved socioeconomic status and life course roles in young adulthood account in good part for differences in the age trajectories. The findings demonstrate the value of the life course perspective in understanding processes of increasing stratification in health behavior and health during the transition to adulthood.
Comparing the Motivational Interviewing Integrity in Two Prevalent Models of Brief Intervention Service Delivery for Primary Care Settings

Abstract This quasi experimental study compared the motivational interviewing (MI) integrity in two prevalent brief intervention (BI) service delivery models for drug abuse. Routine primary care providers (RCPs) and non-routine care providers (NRCPs) performed BIs using an MI style within the same medical setting, patient population, and Screening, Brief Intervention, and Referral for Treatment (SBIRT) protocol. Interventionists (9 RCPs and 6 NRCPs) underwent similar MI training and performed a total of 423 audiorecorded BIs. We compared the MI integrity scores for all audio recorded sessions from these two SBIRT models for up to 40months post MI training. Both groups met the lower standard (beginning proficiency in MI) on 4 of 5 MI integrity scores, but NRCPs met more of the higher standards (competency in MI) than RCPs. There may be limitations with regards to MI fidelity when using RCPs to conduct BIs in some primary care settings. Further experimental investigation is warranted to replicate this finding and identify casual factors of observed differences in MI fidelity.
Detection of thermal and acoustic transients in materials using heterodyned euv radiation

Nonlinear optical photoacoustic techniques have been extended from the visible to the EUV using high harmonics for the first time. This will enable measurements of thermal and acoustic transients in materials with sub-100 nm spatial resolution
Dispositional and situational moderators of female and male causal attributions

To increase understanding of the relationships between gender and causal attributions, dispositional and situational variables were examined to determine if they affected causal attributions differently if the subjects were females or males. Four dispositional variables—locus of control, neuroticism, achievement motivation, and self-esteem—and five situational variables—expectancy of success, self-reported commitment, perceived productivity, perceived task complexity, and actual performance—were examined for their moderating effects on the gender-causal attributional relationships. The dispositional variables did not moderate any causal relationships. By comparison, four situational variables—performance, commitment, productivity, and complexity—moderated at least one of the gender-attribution relationships. It was concluded that more attention should be directed to the identification of situational moderators.
Three-dimensional characterization of dendritic microstructures

Abstract The first complete characterization of a dendritic microstructure is presented. The dendrite morphology is obtained via a novel serial-sectioning process that allows the three-dimensional microstructure of opaque materials to be determined in a routine manner. Using the reconstructed dendrite we determine the spatial distribution of the mean and Gaussian curvature as well as the probability density distributions of these curvatures. These measurements yield many insights into the local processes that shape these topologically complex structures that are vital in setting many material properties.
The Role of the Entorhinal Cortex in Paraphrenia

Evidence derived from postmortem brain studies has implicated the uncal cortex in paraphrenia. In the present review, we expand on the anatomic and physiologic nuances endogenous to this region that make entorhinal cortex pathology an important clinicopathological correlate to paraphrenia. First, we summarize the anatomic landmarks and histologic features that will allow the reader to define the entorhinal region in future research studies. As cortical regions usually project to neighboring cortices, inferences will be drawn as to the function of the entorhinal region based on the surrounding cortical regions. The results will help explain why patients with paraphrenia may exhibit amnestic deficits that stand in contrast to a well-preserved thought process and personality. We also review the results of surgical ablation studies in animals. These studies suggest that some risk factors currently associated with paraphrenia (eg, social isolation) may in reality be an early manifestation of entorhinal pathology. Finally, the author provides a parallelism between the hallucinations observed in some paraphrenic patients and the results of electrical stimulation of the uncal cortex. The results will help explain why hallucinations in paraphrenia are usually limited to the patient’s surroundings.
A tale of two polymers: new insights into helical filaments

Many proteins function as helical polymers within the cell. Two intensively studied examples are eukaryotic actin and bacterial RecA, which belong to two different protein superfamilies. However, most other members of these superfamilies do not polymerize into helical filaments. General features of polymorphism, cooperativity and allostery that emerge from studies of eukaryotic actin and bacterial RecA raise more general issues about how conserved these filamentous structures have been during evolution.
Use of an indirect antiglobulin consumption test to detect isoantibodies following human cancer cell homotransplants.

Resume Un test indirect de consommation de l'antiglobuline (IAGC) a ete utilise pour la mise en evidence, a la surface de la cellule, d'anticorps reagissant avec des cellules cancereuses humaines ((HEp 2 ), cultivees “in vitro”. Cette technique fut employee pour etudier la formation d'anticorps, a la suite d'homogreffes de differentes lignees de cellules cancereuses humaines, chez des receveurs sains et chez patients atteints de cancer en phase avancee. A la suite d'homogreffes primaires, cette technique ne permettait habituellement pas la mise en evidence d'anticorps. Par contre, apres des homogreffes repetees, un anticorps fut detecte dans la moitie des cas environ. Chez les receveurs sains, le taux des anticorps approchait du maximum, deux semaines environ apres la greffe, atteignait ce maximum apres quatre semaines, et diminuait ensuite, pour rester decelable jusqu' a la sixieme ou huitieme semaine. L'anticorps n'etait pas specifique pour la lignee cellulaire transplantee. Chez les receveurs sains, les taux d'anticorps variaient parallelement a la croissance et au rejet du greffon. Cependant, des taux comparables d'isoanticorps apparaissaient chez des sujets cancereux qui rejetaient le greffon avec un delai plus long, montrant par la que l'anticorps serique n'est pas une mesure exacte de la capacite de rejet de ces homogreffes. Les resultats avec le test IAGC sont en accord avec ceux obtenus par la technique de l'agglutination des globules rouges tannes, mais la methode IAGC n'est pas satisfaisante pour isoler des taux tres bas d'anticorps, parce que des modifications s'exprimant par des differences d'une dilution ne sont pas reproductibles. Les serums provenant de nombreux sujets, avant transplantation, et particulierement de patients atteints de cancer ou d'une autre affection alterant l'etat general, donnaient une reaction non specifique qu'il convient de distinguer de l'isoanticorps. La signification de cette reaction non specifique est inconnue.
Band Structure of Homocatenated Indium Polymer

The electronic structure of linear homocatenated indium (In) polymer has been studied by tight-binding band calculations with the extended Huckel approximation. The polymer was found to have semiconducting behavior with a direct gap. The highest occupied crystal orbital (HOCO) of the polymer are formed by σ-bonding between neighboring p orbitals of In atoms, whose σ-electrons were well delocalized along the main chain. The possible presence of σ-conjugation in the chains can result in σ – σ* interband transitions, as in the case of polysilane, which is formed by group 14 elements.
On the cohomology of ring extensions

In this article we are primarily concerned with the relativized cohomology theory of ring extensions, as initiated by G. Hochschild [ 141. Our main objective is to lay the foundation for a general vanishing theory of relativized extension functors. The significance of such a theory rests on the unification it provides for the various classical results from the cohomology theories of groups, associative algebras, and Lie algebras. The approach chosen here heavily emphasizes locally nilpotent operators as an underlying principle for vanishing and isomorphism theorems. Although in algebraic homology theory these concepts have appeared only recently (cf. [5]), they occur implicitly in singular homology theory of topological spaces. The conventional proof of the excision theorem, for instance, resorts, by means of barycentric subdivision, to the construction of a locally nilpotent operator that is chain homotopic to the identity. In Section 1 we study the question to what an extent properties of operators are inherited by resolutions. It is shown that resolutions defined by injective envelopes and projective covers are suitable tools for ordinary homology. In the framework of relative homological algebra of a given ring extension R:S the availability of standard resolutions allows the application of more computational techniques. We show that the commutator algebra of the centralizer C,(S) of S in R operates on these resolutions in a natural fashion. This result in conjunction with a certain homotopy is subsequently utilized to show that the associated action on the spaces Ext;,, S) (M, N) is trivial. The succeeding section combines these techniques with basic facts concerning locally finite operators to establish various vanishing theorems for extension functors. The third section deals with the study of the cohomology theory of Frobenius extensions. We address questions emerging from recent developments in the cohomology theories of finite dimensional modular [9] and finite dimensional restricted Lie algebras [7-93. Our results are closely
Bacteriophage P2 head morphogenesis: cleavage of the major capsid protein.

Abstract The protein products of four P2 head genes have been identified, and their molecular weights estimated by migration in SDS polyacrylamide gels. The product of the N gene is a protein with a molecular weight of 44,000, which is cleaved to give the major capsid protein, N∗, with a molecular weight of 36,000. Two other protein components of the head may also be cleavage products of the N protein. Coupled to the cleavage of the N protein is the cleavage of the O gene product from a 30,000 molecular weight protein to material of less than 17,000 molecular weight. The P gene product has been identified and is bound to rapidly sedimenting material, possibly membrane. The products of genes M, O, and P are not detected in mature phage heads. Mutants in head genes L, M, P, and Q can synthesize head-like structures under nonpermissive conditions, but mutants in genes O and N cannot. A model of P2 head assembly is presented in which the O and N gene products assemble and are cleaved to give a semistable head precursor. This precursor is then acted upon by the four other head gene products to form the mature head.
Supercooling Helium Vapor: Nucleation and Fog Formation Induced by Strong Evaporation

We have studied heterogeneous nucleation of liquid 4He on cesiated surfaces using calorimetric techniques. Nucleation kinetics are strongly influenced by wetting properties. Since liquid 4He does not wet cesium below 2K, substantial supercooling of the vapor is expected on theoretical grounds. Experimentally, however, we have been unable to detect any supercooling in our cells. This may be due to microscopic defects in the Cs coating, which in turn may be related to the fact that we have been unable to find a cell construction material which is wetted by Cs. Somewhat paradoxically, it is possible to supercool helium vapor even in a container made of conventional wetted materials by imposing a large heat and mass flux from the liquid to the vapor across the bulk liquid-vapor interface. When evaporation is sufficiently strong, the vapor above the liquid becomes unstable, and forms a dense fog. Videos of this process show that the fog front propagates rapidly from very near the liquid-vapor interface upward into the vapor. Fog formation near the liquid interface implies that the vapor is in a supercooled metastable state. Qualitative ideas from non-equilibrium thermodynamics and kinetic theory are used to explain this phenomenon.
Computer Simulation of Three-Dimensional Chip Kinematics in Machining

Effective chip control is an essential requirement of modern automatic and computer numerically controlled (CNC) machining operations. This paper asserts that the study of chip control can be divided into three branches—chip dynamics, chip kinematics, and chip breaking mechanics—each having different research emphasis. Chip kinematics is becoming a promising research area, serving as an essential bridge between the other two branches. In developing the mathematical formulation of chip kinematics, this paper introduces three patterns of chip curl, i.e., up-, side-, and lateral-curl, followed by the establishment of a Cartesian coordinate system. Chip form is measured by three geometric parameters: the resultant radius R of chip curl, the pitch P of the chip helix, and the inclined angle θ of the helical axis to the helical surface. It is revealed that the final chip form is determined by four governing variables: chip up-, side-, and lateral-curl radii (Ru , Rs , and Rl ) and chip side-flow angle (ηs ). The effect of Ru , Rs , Rl , and ηs on chip forms is investigated. A set of new chip kinematical equations and computer-simulated chip forms are also established in this paper.Copyright © 2002 by ASME
Determination of ventilatory liver movement via radiographic evaluation of diaphragm position

Abstract Purpose: To determine the accuracy of estimation of liver movement inferred by observing diaphragm excursion on radiographic images. Methods and Materials: Eight patients with focal liver cancer had platinum embolization microcoils implanted in their livers during catheterization of the hepatic artery for delivery of regional chemotherapy. These patients underwent fluoroscopy, during which normal breathing movement was recorded on videotape. Movies of breathing movement were digitized, and the relative projected positions of the diaphragm and coils were recorded. For 6 patients, daily radiographs were also acquired during treatment. Retrospective measurements of coil position were taken after the diaphragm was aligned with the superior portion of the liver on digitally reconstructed radiographs. Results: Coil movement of 4.9 to 30.4 mm was observed during normal breathing. Diaphragm position tracked inferior-superior coil displacement accurately (population σ 1.04 mm) throughout the breathing cycle. The range of coil movement was predicted by the range of diaphragm movement with an accuracy of 2.09 mm (σ). The maximum error observed measuring coil movement using diaphragm position was 3.8 mm for a coil 9.8 cm inferior to the diaphragm. However, the distance of the coil from the top of the diaphragm did not correlate significantly with the error in predicting liver excursion. Analysis of daily radiographs showed that the error in predicting coil position using the diaphragm as an alignment landmark was 1.8 mm (σ) in the inferior-superior direction and 2.2 mm in the left-right direction, similar in magnitude to the inherent uncertainty in alignment. Conclusions: This study demonstrated that the range of ventilatory movement of different locations within the liver is predicted by diaphragm position to an accuracy that matches or exceeds existing systems for ventilatory tracking. This suggests that the diaphragm is an acceptable anatomic landmark for radiographic estimation of liver movement in anterior-posterior projections for most patients.
Mental Models of Boolean Concepts.

Negation, conjunction, and disjunction are major building blocks in the formation of concepts. This article presents a new model-based theory of these Boolean components. It predicts that individuals simplify the models of instances of concepts. Evidence corroborates the theory and challenges alternative accounts, such as those based on minimal descriptions, algebraic complexity, or structural invariance. A computer program implementing the theory yields more accurate predictions than these rival accounts. Two experiments showed that the numbers of models of a Boolean concept predict the difficulty of formulating a description of it. As mental models may also underlie deductive reasoning, the present theory integrates two hitherto separate areas of investigation.
Phenotyping mouse pulmonary function in vivo with the lung diffusing capacity

The mouse is now the primary animal used to model a variety of lung diseases. To study the mechanisms that underlie such pathologies, phenotypic methods are needed that can quantify the pathologic changes. Furthermore, to provide translational relevance to the mouse models, such measurements should be tests that can easily be done in both humans and mice. Unfortunately, in the present literature few phenotypic measurements of lung function have direct application to humans. One exception is the diffusing capacity for carbon monoxide, which is a measurement that is routinely done in humans. In the present report, we describe a means to quickly and simply measure this diffusing capacity in mice. The procedure involves brief lung inflation with tracer gases in an anesthetized mouse, followed by a 1 min gas analysis time. We have tested the ability of this method to detect several lung pathologies, including emphysema, fibrosis, acute lung injury, and influenza and fungal lung infections, as well as monitoring lung maturation in young pups. Results show significant decreases in all the lung pathologies, as well as an increase in the diffusing capacity with lung maturation. This measurement of lung diffusing capacity thus provides a pulmonary function test that has broad application with its ability to detect phenotypic structural changes with most of the existing pathologic lung models.
Development of the gin trap reflex in Manduca sexta: a comparison of larval and pupal motor responses

1. Responses of motor neurons in larvae and pupae ofManduca sexta to stimulation of tactile sensory neurons were measured in both semiintact, and isolated nerve cord preparations. These motor neurons innervate abdominal intersegmental muscles which are involved in the production of a general flexion reflex in the larva, and the closure reflex of the pupal gin traps. 2. Larval motor neurons respond to stimulation of sensory neurons innervating abdominal mechanosensory hairs with prolonged, tonic excitation ipsilaterally, and either weak excitation or inhibition contralaterally (Figs. 4A, 6). 3. Pupae respond to tactile stimulation of mechanosensory hairs within the gin traps with a rapid closure reflex. Motor neurons which innervate muscles ipsilateral to the stimulus exhibit a large depolarization, high frequency firing, and abrupt termination (Figs. 2, 4B). Generally, contralateral motor neurons fire antiphasically to the ipsilateral motor neurons, producing a characteristic triphasic firing pattern (Figs. 7, 8) which is not seen in the larva. 4. Pupal motor neurons can also respond to sensory stimulation with other types of patterns, including rotational responses (Fig. 3 A), gin trap opening reflexes (Fig. 3 B), and ‘flip-flop’ responses (Fig. 9). 5. Pupal motor neurons, like larval motor neurons, do not show oscillatory responses to tonic current injection, nor do motor neurons of either stage appear to interact synaptically with one another. Most pupal motor neurons also exhibit i-V properties similar to those of larval motor neurons (Table 1; Fig. 10). Some pupal motor neurons, however, show a marked non-linear response to depolarizing current injection (Fig. 11).