cssi/SciSciGPT-SciSciNet huggingface dataset:
Theories and models on the biology of cells in space

A wide variety of observations on cells in space, admittedly made under constraining and unnatural conditions in may cases, have led to experimental results that were surprising or unexpected. Reproducibility, freedom from artifacts, and plausibility must be considered in all cases, even when results are not surprising. The papers in symposium on 'Theories and Models on the Biology of Cells in Space' are dedicated to the subject of the plausibility of cellular responses to gravity -- inertial accelerations between 0 and 9.8 m/sq s and higher. The mechanical phenomena inside the cell, the gravitactic locomotion of single eukaryotic and prokaryotic cells, and the effects of inertial unloading on cellular physiology are addressed in theoretical and experimental studies.
Depth cueing for visual search and cursor positioning

Previously reported research has illustrated the dependence of stereoscopic utility on the figures of merit selected as well as the display application. This paper reports on a subsequent experiment in which subjects not only judged the relative depth ordering and subjective quality of planar symbols in a 3-D plan view display, but also manipulated a 3-D cursor. The 3-D images were presented on a Tektronix SGS 620 field-sequential stereoscopic CRT (19-inch diagonal, 120-Hz field rate, passive glasses). Three sources of depth information (cue types) were combined factorially to construct exemplary 3-D images: relative size (angular subtense decreased with increasing depth); stereo (binocular disparity varied from crossed to uncrossed with increasing depth); and luminance (luminance decreased with increasing depth). In addition, depth cue salience and display complexity were included in the factorial design. Inclusion of each of the three depth cues produced significantly faster depth judgments, more accurate cursor positioning, and improved image quality ratings. While the use of multiple depth cues had a complementary effect on performance and image quality ratings (i.e., more was better), the effects were clearly interactive rather than strictly additive.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Erratum to: Quality control verification and mapping for chemical application

Recent re-evaluation of the original work published in 2003 found that theoretical droplet size diameters were reported incorrectly. In all cases reported in the original work, the theoretical droplet diameters were under-reported by 17.5%. The error in theoretical droplet diameter resulted in an incorrect estimate for spread factor (reported as 0.392 in the original work). The correct spread factor, based on the ratio of the ‘‘correct’’ theoretical droplet diameter to the measured stain diameter is 0.474. In all cases, the droplet size distributions were actually 17.2% higher than what was originally reported. It should be noted that the conclusions from the original work are unchanged, viz., blended-pulse control during large-scale spray applications provides a wider dynamic range and better control for maintaining consistency of spray deposition. Results presented in the original work showed that droplet size changes for mitigation of spray drift were possible while sensing weather conditions and potentially hazardous sprayer locations. Additionally, use of on-board GPS and environmental data collection equipment for mapping application parameters and environmental conditions can assist applicators in providing efficacious and safe applications while also providing documentation of the application for regulatory compliance.
Field Study to Investigate WIDE Technology for TCE Extraction

A full-scale field study was conducted using well injection depth extraction (WIDE) technology to remove trichloroethylene (TCE) from subsurface profiles with fine-grained soils. WIDE incorporates the use of geosynthetic wick drains, attached to an aboveground PVC pipe network, designed to (1) extract contaminated fluids from a specific depth using vacuum pressure, and/or (2) inject flushing solutions. Both extraction-only and concurrent injection-extraction testing schemes were conducted, and fluid flow rates, TCE recovery rates, and groundwater elevations were monitored over a 9 month time interval. During extraction-only operational schemes, gas-phase TCE extraction rates were significantly higher than liquid-phase extraction rates due to the increased volume of air within the geosynthetic wells and PVC piping. TCE extraction rates were less than 2,000 mg∕h for airflow rates less than 100,000 L∕h , and increased significantly to 5,700 mg∕h as the airflow rate approached 600,000 L∕h . Long term testing ...
Measurement of the magnetic field of the CDF magnet

The magnetic field of the CDF (Collider Detector at Fermilab) superconducting solenoid has been measured using a newly designed field mapping device. NMR probes and a system of three orthogonal search coils were used as sensing elements. The central uniform region inside the solenoid coil and the fringing field in the conical end plugs were measured. The detailed field distribution and its characteristics are described.
Women Experiencing Psychological Abuse: Are They a Homogenous Group?

Dichotomizing women as “abused” versus “not abused” assumes that any psychological maltreatment results in similar outcomes. A national sample of women in conflictual relationships completed an online survey. Women with no incidence (N = 33), the lowest quartile (N = 86), and the top quartile (N = 81) of psychological maltreatment demonstrated significant differences in reactions to the maltreatment, mental health indicators, personality variables, perceived harm, problematic relationship schemas, and response styles. Women with no psychological abuse and women in the lowest quartile produced similar scores that were typically distinct from the top-quartile women. Effective treatment of women with lower amounts of psychological abuse might not require a unique intervention likely necessary for women experiencing much psychological abuse.
Real-time performance of an open-source protocol stack for low-cost, embedded systems

Modern embedded devices often require some form of network connectivity, to offer features like remote configuration, diagnostics, and firmware updates. The availability of open-source, lightweight, and portable protocol stacks, makes this goal relatively easy to accomplish, even on very low-cost devices. Interoperability is guaranteed because they implement, at the very least, the TCP/IP and UDP/IP protocols on an Ethernet interface. However, these applications are quite undemanding for what concerns real-time and, for this reason, little is known about the real-time characteristics of the underlying protocol stacks. This paper shows that an open-source protocol stack, when properly coupled with a real-time operating system and an Ethernet interface, can indeed reach an acceptable performance level and thus support an Ethernet-basedfieldbus protocol on the device side.
Site-Directed Mutagenesis Studies of Selected Motif and Charged Residues and of Cysteines of the Multifunctional Tetracycline Efflux Protein Tet(L)

All of the transmembrane glutamates of Tet(L) are essential for tetracycline (TET) resistance, and E397 has been shown to be essential for all catalytic modes, i.e., TET-Me(2+) and Na(+) efflux and K(+) uptake. Loop residues D74 and G70 are essential for TET flux but not for Na(+) or K(+) flux. A cysteineless Tet(L) protein exhibits all activities.
Tobit factor analysis

A new approach is proposed for data which are skewed and have a sizeable proportion of observation at variable end points. Using a covariance structure modelling framework, the new approach assumes censored multivariate normal variables. Using bivariate information, this leads to the use of ‘tobit’ correlations in weighted least squares estimation. The behaviour of the tobit approach is compared to that of normal theory estimation and ADF estimation.
Patients With Positive Axillary Lymph Nodes: How to Use Genomic Assays

The treatment of breast cancer is continually evolving. Standard treatment for early stage, node positive breast cancer has included adjuvant chemotherapy. As we learn more about differences in a tumor’s genetic makeup that result in different patterns of recurrence and survival, we are starting to include gene expression in addition to the routine clinical and pathological factors when we make treatment recommendations. For lymph node negative, early stage breast cancer, there are two genomic assays in routine use to predict prognosis and benefit from adjuvant chemotherapy. There is emerging data to support that the same tests may also predict prognosis and chemotherapy benefit, or lack thereof, in lymph node positive tumors. Currently there are no standard of care and this is an area in which more research is being done. Given that the biology of breast tumors is independent of nodal status, there are certainly cases of node positive early stage breast cancer where clinicians can feel comfortable making treatment decisions based on genomic assays. These include women with micrometastases in the lymph nodes or those with one to three positive lymph nodes. Currently, the genomic assays are limited to use in tumors that are estrogen receptor positive. It is still clearly the standard of care to administer chemotherapy to estrogen receptor negative, lymph node positive tumors.
SINGLE DAILY DOSE OF ANTITHYROID MEDICATION IN ADOLESCENTS WITH HYPERTHYROIDISM

Many adolescent patients with hyperthyroidism fail to take antithyroid medication several times daily and, consequently, remain hyperthyroid. Greer, (NEJM,272:888,65) and Barnes, (JCEM,35:250,72) have reported successful therapy of hyperthyroid adults using a large single daily dose (SDD) of propylthiouracil (PTU) or methimazole (M). We have studied 9 adolescents with hyperthyroidism, 7 initially treated with a SDD of PTU (300mg/m2/24hr) and 2 with a SDD of M(30mg/m2/24hr). Over a 3 month follow-up period, we have monitored several parameters: symptoms of patient; opinion of physician re: thyroid status; weight change; goiter size; WBC, and serum thyroxine(CPB). After 3 months, 5 patients were asymptomatic and 4 patients experienced minimal symptoms. The physician considered 2 patients euthyroid and 7 definitely improved but slightly hyperthyroid. Gain in weight, expressed as mean ±S.E. was 3.0 ± 1.3kg (range:−2.5 to 10.9); P<0.035. Goiter size decreased in 7, remained the same in 1, and increased in 1 patient. At no time did the WBC fall below 4,000/cc in any of the 9 patients. Initial thyroxine level was 21.6 ± 1.7ug%, (range 18.1 to 31.0). Decrease in thyroxine was 10.0 ± 2.2 (range 2.0 to 24.8). Although follow-up has been relatively short, these results suggest that a SDD of antithyroid medication is successful and safe in inducing a remission in adolescents with hyperthyroidism and would enhance compliance.
Male-Specific Cuticular Compounds of the Six Drosophila paulistorum Semispecies: Structural Identification and Mating Effect

We have identified cuticular pheromones that sustain the integrity of the six Drosophila paulistorum semispecies. Hexane extracts of male and female cuticles were separated on a silica gel column and analyzed using gas chromatography/mass spectrometry. Both sexes of each of the six semispecies have the same fifteen major cuticular components, all hydrocarbons ranging from C31 to C37. However, all males have four additional ester compounds. Bioassay observations showed that this four-component ester complex imparts a strong anti-aphrodisiac effect on intra-semispecific mating behavior, thus confirming its pheromonal role. The three major ester components are methyl (Z)-9-tetradecenoate (C(15)H(28)O(2)), 11-docosenyl acetate (C(24)H(46)O(2)), and 19-triacontenyl acetate (C(32)H(62)O(2)). The fourth ester is a di-unsaturated acetate with molecular formula C(32)H(60)O(2), but the positions of unsaturation have not been determined. Bioassays indicate that the male-specific complex of the transitional semispecies, the relict ancestor, imparts anti-aphrodisiac effects on the other semispecies as well, but effectiveness decreases with phylogenetic distances. Across the six semispecies, the male-specific compounds are the same, but vary quantitatively. Apparently, the quantitative differences among these incipient species act efficiently to preclude hybridization in nature. Because Drosophila paulistorum is a cluster of incipient species, this opportunity to observe pheromonal influences on speciation is unique.
Iron and Human Disease

Introduction. Iron, Aging, and Human Disease: Historical Background and New Hypotheses (R.B. Lauffer). Chemistry and Molecular Biology of Iron and Iron-Binding Proteins: Structure and Molecular Biology of Iron-Binding Proteins and the Regulation of 'Free' Iron Pools (R.R. Crichton and R.J. Ward). Genetic Control of the Genes for Iron Storage and Transport: Links with the Acute Phase Response (J.T. Rogers). Iron Accumulation and METABOLISM in Humans: Iron Balance in Western Societies as Measured by Serum Ferritin (J.W. Halliday and B.A. Leggett). Hereditary Hemochromatosis and Other Diseases Associated with Iron Overload (J.W. Halliday and L.W. Powell). Iron and the Immune System (J.H. Brock). Cellular Acquisition of Iron and the Iron withholding Defense Against Microbial and Neoplastic Invasion (E.D. Weinberg). Iron and Oxidative Stress: Iron and Damage to Biomolecules (B. Halliwell). Lipofuscin, Lysosomes, and Iron (U.T. Brunk, M.R. Marzabadi, and C.B. Jones). Roles for Iron in Cardiovascular Diseases: Role of Iron in the Oxidative Modification of Low Density Lipoprotein (S. Parthasarathy). Iron and Myocardial Reperfusion Injury (J.L. Zweier). Stored Iron as a Risk Factor for Ischemic Heart Disease (J. Sullivan). Iron and Stroke (L.S. Terada, I.R. Willingham, and J.E. Repine). Roles for Iron in Other COmmon Diseases: Iron and Cancer (R.G. Stevens). Brain Iron and Nigra-Striatal Dopamine Neurons in Parkinson's Disease (D. Ben-Shachar, and M. Youdim). Proteins of Iron Regulation in Alzheimer's Disease (J.R. Connor). Iron-Promoted Oxidative Damage in Rheumatic Diseases (C.W. Trenam, P.G. Winyard, C.J. Morris, and D.R. Blake). Iron and Ethanol-Induced Tissue Damage (A.I. Cederbaum). Iron Metabolism and Oxygen Radical Injury in Premature Infants (J. Sullivan). Implications for Prevention and Therapy: Preventive Measures for the Maintenance of Low But Adequate Iron Stores (R.B. Lauffer). Therapeutic Strategies to Inhibit Iron-Catalyzed Tissue Damage (B. Hed lund and P.E. Hallaway) Iron and Oxidative Balance (J. McCord).
Analyzing spike trains with circular statistics

In neuroscience, specifically electrophysiology, it is common to replace a measured sequence of action potentials or spike trains with delta functions prior to analysis. We apply a method called circular statistics to a time series of delta functions and show that the method is equivalent to the power spectrum. This technique allows us to easily visualize the idea of the power spectrum of spike trains and easily reveals oscillatory and stochastic behavior. We provide several illustrations of the method and an example suitable for students, and suggest that the method might be useful for courses in introductory biophysics and neuroscience.
Reliability modeling of flexible manufacturing systems

Abstract This paper presents a modeling approach for assessing the reliability of flexible manufacturing systems. FMSs are very difficult to model by analytical methods, because of their complexity. Many of their parameters, especially equipment failure and repair rates, exhibit great uncertainty. The proposed approach owes its success to an effective heuristic method called Group Method of Data Handling . The algorithm has proven very useful for modeling complex nonlinear systems with large number of parameters and little collected data. By combining it with analytical methods, models that closely predict the FMS output are produced that become valuable tools for evaluating FMSs during their design and operation.
Efficient distributed channel allocation for cellular networks

The performance of a distributed dynamic channel allocation algorithm is measured by the call blocking rate, the number of messages exchanged per channel acquisition and the delay incurred in acquiring a channel. In general, there are two approaches in designing distributed channel allocation algorithms: Search and Update. Both of these approaches have advantages and disadvantages. The update approach has shorter acquisition delay and lower call blocking rate, but higher message complexity. On the other hand, the search approach has lower message complexity, but longer acquisition delay and higher call blocking rate. In this paper, we first propose a novel distributed acquisition algorithm, which has similar message complexity as the search approach and similar acquisition delay as the update approach. Then, we present a channel selection algorithm and integrate it into our distributed acquisition algorithm. By a rigorous analysis in terms of delay and message complexity, we show that our channel selection algorithm performs significantly better than the update approach [X. Dong, T.H. Lai, Proceedings of the International Conference on Distributed Computing systems, 1997] and the search approach [R. Prakash, N. Shivaratri, M. Singhal, Proceedings of the 14th ACM Symposium on Principles of Distributed Computing, 1995, pp. 47-56]. Detailed simulation experiments are carried out in order to evaluate our proposed methodology. The performance of our algorithm is compared with those of the Geometric strategy [A. Baiocchi, F.D. Proscoli, F. Grilli, F. Sestini, IEEE Trans. Veh. Technol. February (1995) 14-23], the Search approach [R. Prakash, N. Shivaratri, M. Singhal, Proceedings of the 14th ACM Symposium on Principles of Distributed Computing, 1995, pp. 47-56] and the Update approach [X. Dong, T.H. Lai, Proceedings of the International Conference on Distributed Computing systems, 1997]. Simulation results show that our algorithm outperforms all other approaches in terms of call blocking probability under uniform as well as non-uniform traffic distributions.
CH4/NH3/H2O spark tholin: chemical analysis and interaction with Jovian aqueous clouds.

Abstract The organic solid (tholin) produced by spark discharge in a CH4 + NH3 + H2O atmosphere is investigated, along with the separable components of its water-soluble fraction. The chemistry of this material serves as a provisional model for the interaction of Jovian organic heteropolymers with the deep aqueous clouds of Jupiter. Intact (unhydrolyzed) tholin is resolved into four chemically distinct fractions by high-pressure liquid chromatography (HPLC). Gel filtration chromatography reveals abundant components at molecular weights ⋍600–700 and 200–300 Da . Gas chromatography/mass spectrometry of derivatized hydrolysis products of unfractionated tholin shows about 10% by mass protein and nonprotein amino acids, chiefly glycine, alanine, aspartic acid, β-alanine, and β-aminobutyric acid, and 12% by mass other organic acids and hydroxy acids. The stereospecificity of alanine is investigated and shown to be racemic. The four principal HPLC fractions yield distinctly different proportions of amino acids. Chemical tests show that small peptides or organic molecules containing multiple amino acid precursors are a possibility in the intact tholins, but substantial quantities of large peptides are not indicated. Candidate 700-Da molecules have a central unsaturated, hydrocarbon- and nitrile-rich core, linked by acid-labile (ester or amide) bonds to amino acid and carboxylic acid side groups. The core is probably not HCN “polymer.” The concentration of amino acids from tholin hydrolysis in the lower aqueous clouds of Jupiter, about 0.1 μM, is enough to maintain small populations of terrestrial microorganisms even if the amino acids must serve as the sole carbon source.
Probabilistic thinking and death anxiety: a terror management based study.

Terror Management Theory has been utilized to understand how death can change behavioral outcomes and social dynamics. One area that is not well researched is why individuals willingly engage in risky behavior that could accelerate their mortality. One method of distancing a potential life threatening outcome when engaging in risky behaviors is through stacking probability in favor of the event not occurring, termed probabilistic thinking. The present study examines the creation and psychometric properties of the Probabilistic Thinking scale in a sample of young, middle aged, and older adults (n = 472). The scale demonstrated adequate internal consistency reliability for each of the four subscales, excellent overall internal consistency, and good construct validity regarding relationships with measures of death anxiety. Reliable age and gender effects in probabilistic thinking were also observed. The relationship of probabilistic thinking as part of a cultural buffer against death anxiety is discussed, as well as its implications for Terror Management research. Language: en
Potentials of mean force for acetylcholine unbinding from the alpha7 nicotinic acetylcholine receptor ligand-binding domain.

The nicotinic acetylcholine receptor is a prototype ligand-gated ion channel that mediates signal transduction in the neuromuscular junctions and other cholinergic synapses. The molecular basis for the energetics of ligand binding and unbinding is critical to our understanding of the pharmacology of this class of receptors. Here, we used steered molecular dynamics to investigate the unbinding of acetylcholine from the ligand-binding domain of human alpha7 nicotinic acetylcholine receptor along four different predetermined pathways. Pulling forces were found to correlate well with interactions between acetylcholine and residues in the binding site during the unbinding process. From multiple trajectories along these unbinding pathways, we calculated the potentials of mean force for acetylcholine unbinding. Four available methods based on Jarzynski's equality were used and compared for their efficiencies. The most probable pathway was identified to be along a direction approximately parallel to the membrane....
Iron as a therapeutic agent in pediatric practice.

Summary 1. Iron salts have a well-established role in the prevention and treatment of iron deficiency states. 2. Iron should be administered as a simple iron salt, in divided doses, and for adequate periods of time. Adjuncts such as cobalt, folic acid, molybdenum, copper, and ascorbic acid are of no practical use in the treatment of iron deficiency. 3. In rare instances in which chronic gastrointestinal disease prohibits the absorption of oral iron, iron-dextran can be given intramuscularly. In other situations it is no more effective than iron salts given by mouth. 4. Specific diagnosis is the keystone to successful and safe iron therapy. Chronic, toxic iron overload is a potential danger in any patient being given iron in the absence of a proper diagnosis. 5. The anger of accidental, acute iron poisoning in small children must be appreciated by any family in which medicinal iron is to be used.
Surface proteins of Bordetella pertussis

Bordetella pertussis cells express multiple virulence-associated surface proteins, including adenylate cyclase, agglutinogens 2 and.3, filamentous hemagglutinin, pertussis toxin, and outer-membrane protein (Omp) 30/32 and Omp91. Surface proteins that are not virulence-associated include three peptidoglycan-associated Omps of apparent molecular weights 40,000, 25,000, and 18,000. Omp40 is an anion-selective porin and is the most abundant surface protein of virulent and avirulent cells. Three independent approaches immunomicroscopy, surface radioiodination, and isolation of Triton X-100-insoluble envelope proteins - suggest that the Triton-insoluble fraction of the B. pertussis cell envelope is the outer membrane. Agglutinogens 2 and 3 and filamentous hemagglutinin lie outside the outer membrane, the first two as fimbriae and the last as a microcapsule. Adenylate cyclase and pertussis toxin are present in the outer membrane but may be present transiently or present in small amounts.
A Simplified General Method for Resistance-Capacity Coupled Amplifier Design

The steady state analysis of the general resistance-capacity coupled amplifier stage is thrown into such a form that any amplifier stage is characterized by three easily computed constants which make it possible to read off its complete steady state performance immediately from three perfectly general analytical curves. These curves are shown, as are some applications of the method.
Rapid word identification in pure alexia is lexical but not semantic.

Following the notion that patients with pure alexia have access to two distinct reading strategies-letter-by-letter reading and semantic reading-a training program was devised to facilitate reading via semantics in a patient with pure alexia. Training utilized brief stimulus presentations and required category judgments rather than explicit word identification. The training was successful for trained words, but generalized poorly to untrained words. Additional studies involving oral reading of nouns and of functors also resulted in improved reading of trained words. Pseudowords could not be trained to criterion. The results suggest that improved reading can be achieved in pure alexia by pairing rapidly presented words with feedback. Focusing on semantic processing is not essential to this process. It is proposed that the training strengthens connections between the output of visual processing and preexisting orthographic representations.
Enabling Real-Time Querying of Live and Historical Stream Data

Applications that query data streams in order to identify trends, patterns, or anomalies can often benefit from comparing the live stream data with archived historical stream data. However, searching this historical data in real time has been considered so far to be prohibitively expensive. One of the main bottlenecks is the update costs of the indices over the archived data. In this paper, we address this problem by using our highly-efficient bitmap indexing technology (called FastBit) and demonstrate that the index update operations are sufficiently efficient for this bottleneck to be removed. We describe our prototype system based on the TelegraphCQ streaming query processor and the FastBit bitmap index. We present a detailed performance evaluation of our system using a complex query workload for analyzing real network traffic data. The combined system uses TelegraphCQ to analyze streams of traffic information and FastBit to correlate current behaviors with historical trends. We demonstrate that our system can simultaneously analyze (1) live streams with high data rates and (2) a large repository of historical stream data.
A horizontal approach for software process improvement

Software process improvement practice and research have predominantly assumed a vertical approach to definition and change. Our studies show that vertical approaches have inherent difficulties. We have developed a new approach called horizontal change (HOC-A) that provides a new environment for change in software development organizations. We describe some of the difficulties of the vertical process improvement approaches and demonstrate, with examples, how the horizontal change approach addresses these difficulties.
Clinical Utility of Proton Magnetic Resonance Spectroscopy in Characterizing Breast Lesions

Proton magnetic resonance spectroscopy ((1)H MRS) of the breast has been proposed as an adjunct to the magnetic resonance imaging (MRI) examination to improve the specificity of distinguishing malignant breast tumors from benign breast tumors. In this review, we carry out a pooled analysis of the clinical breast (1)H MRS studies undertaken to date to determine the factors that influence the diagnostic performance of this method. In total, five studies of breast (1)H MRS from four independent centers around the world have been published to date. Altogether, 153 tumors were examined, 100 of which were confirmed histologically to be malignant and 53 of which were benign. The lesions presenting a detectable composite choline signal in their corresponding (1)H MR spectra were diagnosed as malignant, whereas the lesions with no choline signal were diagnosed as benign. The sensitivity and specificity of breast (1)H MRS for detecting breast cancer were 83% (95% confidence interval [CI] = 73% to 89%) and 85% (95% CI = 71% to 93%), respectively, and both values could be as high as 92% after technical exclusions. In a subgroup of 20 young women, the sensitivity and the specificity of the method approached 100%. The factors limiting the sensitivity of the examination were mainly technical. The use of the composite choline signal as a marker for malignancy in breast (1)H MRS is a robust method with highly reliable interpretation, because it is based on the appearance of a single peak. The method is likely to provide even better results with technologic advances in breast MRS that lead to the improved detection of the composite choline signal.
An HDP Model for Inducing Combinatory Categorial Grammars

We introduce a novel nonparametric Bayesian model for the induction of Combinatory Categorial Grammars from POS-tagged text. It achieves state of the art performance on a number of languages, and induces linguistically plausible lexicons.
Economic Development Perspective and City Leadership

The viability of traditional economic development strategies has long been questioned by urban policy scholars; yet traditional strategies remain the norm among city leaders. Traditional concerns emphasize economic and business considerations at the expense of nontraditional community considerations such as quality of life. In this paper, we examine the conditions under which city leaders give weight to nontraditional community concerns when making economic development decisions. Our analysis of the results of a survey conducted of more than 200 leaders in over 150 Texas cities indicates that although traditional economic development concerns remain dominant, certain conditions may exist that allow or compel city leaders to give increased weight to non-traditional community considerations. Conditions revealed by our study include the socioeconomic status of Texas cities and the relative differences in leadership positions and professionalism among city leaders. The paper concludes with a discussion of how our study contributes to the literature about economic development policy and points to avenues for future research on the conditions under which decision-making strategies are pursued by city leaders.
MAGNETIC RESONANCE IMAGING OF THE LIGAMENTOUS STRUCTURES OF THE OCCIPITOATLANTOAXIAL REGION IN THE DOG

Our objectives were to establish a magnetic resonance (MR) protocol for the examination of, and then describe, the normal ligaments and the supporting structures of the occipitoatlantoaxial region. This was done in 10 cadaver dogs. In addition, MR images of three patients with cervical pain localized to the occipitoatlantoaxial region are included to provide examples of ligamentous abnormalities. All ligaments were hypointense in all pulse sequences. The apical, dorsal atlantoaxial, and dorsal longitudinal vertebral ligaments were seen best in the sagittal T1W and PD-weighted images. The transverse ligament was best visualized in the transverse plane in all pulse sequences and appeared to be confluent with the dorsal longitudinal vertebral ligament dorsal to the dens in the sagittal plane. A 20° dorsal plane reconstructed image in 0.6-mm slice thickness was necessary to visualize the alar ligaments, which were visible in 9/10 dogs. The dorsal longitudinal vertebral ligament appeared continuous with the apical ligament and tectorial membrane. Abnormalities in clinically affected dogs included thickening of the alar ligaments, absence of transverse ligament and elongation, and irregularity of the apical ligament.
Religiosity and Loneliness Among the Elderly

Based on a deprivation model of religiosity we analyze the relationship between two dimensions of religiosity and loneliness among the elderly with the effects of involvement in various types of family and friendship relations controlled and compared with the effects of religiosity. Data were collected through interviews with 131 residents of a 199-unit apartment facility for the elderly. Results of the regression analysis showed that greater involvement in the social aspects of religion was significantly related to less loneliness more consistently than involvement in the variousfamily andfriendship relations. In contrast, the subjective dimension of religiosity was not significantly related to loneliness with the social contact variables controlled, even though the direction was as hypothesized
Thresher: an improved algorithm for peak height thresholding of microbial community profiles.

Motivation: This article presents Thresher, an improved technique for finding peak height thresholds for automated rRNA intergenic spacer analysis (ARISA) profiles. We argue that thresholds must be sample dependent, taking community richness into account. In most previous fragment analyses, a common threshold is applied to all samples simultaneously, ignoring richness variations among samples and thereby compromising cross-sample comparison. Our technique solves this problem, and at the same time provides a robust method for outlier rejection, selecting for removal any replicate pairs that are not valid replicates. Results: Thresholds are calculated individually for each replicate in a pair, and separately for each sample. The thresholds are selected to be the ones that minimize the dissimilarity between the replicates after thresholding. If a choice of threshold results in the two replicates in a pair failing a quantitative test of similarity, either that threshold or that sample must be rejected. We compare thresholded ARISA results with sequencing results, and demonstrate that the Thresher algorithm outperforms conventional thresholding techniques. Availability and Implementation: The software is implemented in R, and the code is available at http://verenastarke.wordpress.com or by contacting the author. Contact: vstarke@ciw.edu or http://verenastarke.wordpress.com Supplementary information: Supplementary data are available at Bioinformatics online.
Intervention research, theoretical mechanisms, and causal processes related to externalizing behavior patterns

Intervention research with children and adolescents has suffered from a dearth of relevant theoretical grounding and from the lack of a reciprocal "feedback" mechanism by which clinical trials can inform relevant theorizing and conceptualization. There are hopeful signs, however, of increasing confluence between clinical efforts and theoretical models. Indeed, the key issue I discuss is how intervention studies can yield information about developmental and clinical theory as well as mechanisms related to psychopathology. Specific research examples in the field, particularly those emanating from the Multimodal Treatment Study of Children with attention deficit/ hyperactivity disorder (MTA study), reveal that probes of moderator and mediator variables can clearly enhance our knowledge of relevant processes and mechanisms. In fact, recent MTA findings have relevance for models of genetic and epigenetic influence on symptomatology related to attentional deficits and hyperactivity. It would be overzealous, however, to make premature claims regarding etiologic variables from intervention research, as treatment studies typically address variables that are causally far "downstream" from primary causal factors and most clinical trials have statistical power that is barely sufficient for main outcome questions, much less mediational linkages. Overall, the field has severely underutilized experimental intervention research to subserve the dual ends of improving the lives of youth and advancing theoretical conceptualization regarding development and psychopathology.
Studying Signal Transduction in Single Dendritic Spines

Many forms of synaptic plasticity are triggered by biochemical signaling that occurs in small postsynaptic compartments called dendritic spines, each of which typically houses the postsynaptic terminal associated with a single glutamatergic synapse. Recent advances in optical techniques allow investigators to monitor biochemical signaling in single dendritic spines and thus reveal the signaling mechanisms that link synaptic activity and the induction of synaptic plasticity. This is mostly in the study of Ca2+-dependent forms of synaptic plasticity for which many of the steps between Ca2+ influx and changes to the synapse are now known. This article introduces the new techniques used to investigate signaling in single dendritic spines and the neurobiological insights that they have produced.
Diagnostic and Prognostic Role of Basic Fibroblast Growth Factor in Wilms' Tumor Patients'

Basic fibroblast growth factor (bFGF) is a potent angiogenic peptide implicated in the growth and metastasis of solid tumors. Elevated concentrations of bFGF have been found in the urine of patients with bladder, prostate, and renal tumors. Furthermore, urinary bFGF levels have been shown to correlate with extent of disease. In order to test the utility of urinary bFGF as a Wilms' tumor marker, we measured bFGF levels in preoperative and postoperative urine samples from 97 patients with Wilms' tumor. Preoperative urine samples (n = 97), early postoperative samples obtained from 1 to 3 weeks after surgery (n = 43), and late postoperative samples obtained from 1 to 6 months after surgery (n = 66) were collected from Wilms' tumor patients at 30 institutions between 1989 and 1993. Urine samples from age-matched controls (n = 17) were also obtained. The bFGF levels were determined in duplicate by a competitive sandwich ELISA capable of measuring bFGF at the pg/ml level. Samples were normalized for creatinine content. Urinary bFGF was elevated in 42% of preoperative samples when compared to controls (>90th percentile of normal). Patients with stage III, IV, and V disease had significantly higher preoperative levels of urinary bFGF when compared to patients with stage I and II disease (P < 0.01). Patients with relapse or persistent disease had significantly elevated late postoperative bFGF levels when compared to disease-free patients and controls (P < 0.05). Thus, in patients with Wilms' tumor, elevated preoperative urinary bFGF levels raise the suspicion of aggressive disease while elevated postoperative levels may indicate recurrence or persistence of disease. These data suggest that bFGF is a biological marker for Wilms' tumor and may have a role in the evaluation of patients with this disease.
Elastic Dislocations in a Layered Half‐Space–II The Point Source

Summary The static displacement and strain fields caused by the introduction of a shear dislocation point source into a layered elastic half space have been evaluated using a Thomson-Haskell matrix method (Singh). The point source was found to be an adequate representation of a fault at distances greater than four fault lengths. Gross earth structure (oceanic, shield and tectonic models) cause fields that differ little from those of a uniform half space. However, significant departures from the uniform half-space fields are found to be caused by low rigidity layers, both at the surface (representing sediment cover) and at depth (representing possible zones of partial melt). Both of these features cause complexities in the strain fields that depend on the source orientation and source-receiver distance, and these may result in amplification or attenuation of the uniform halfspace fields by factors of up to 10.
Splicing-related catalysis by protein-free snRNAs

Removal of intervening sequences from eukaryotic messenger RNA precursors is carried out by the spliceosome, a complex assembly of five small nuclear RNAs (snRNAs) and a large number of proteins. Although it has been suggested that the spliceosome might be an RNA enzyme, direct evidence for this has been lacking, and the identity of the catalytic domain of the spliceosome is unknown. Here we show that a protein-free complex of two snRNAs, U2 and U6, can bind and position a small RNA containing the sequence of the intron branch site, and activate the branch adenosine to attack a catalytically critical domain of U6 in a reaction that is related to the first step of splicing. Our data provide direct evidence for the catalytic potential of spliceosomal snRNAs.
Implementing a Computerized Triage System in the Emergency Department

Information Technology (IT) solutions are rapidly being developed for different health care applications throughout the country’s hospitals. The development and implementation of IT applications go through different phases. To successfully implement an IT application, these phases have to be merged with process re-engineering and organizational changes. The required organizational changes are critical to the overall success of IT implementation projects, but the required efforts to achieve the institutional level of commitment remain underestimated and, as a result, often cause unforeseen outcomes and implementation failures. From the very first moments of an IT implementation effort, the technological system capabilities must be tightly coupled with change processes and user involvement. Although common sense supports the idea that the IT application should support a health care provider in caring for patients, it frequently occurs that health care providers are asked to support the IT application. This may lead to the design of systems that have a lower degree of user acceptance and data integrity.
Simulator sickness during driving simulation studies

While driving simulators are a valuable tool for assessing multiple dimensions of driving performance under relatively safe conditions, researchers and practitioners must be prepared for participants that suffer from simulator sickness. This paper describes multiple theories of motion sickness and presents a method for assessing and reacting to simulator sickness symptoms. Results showed that this method identified individuals who were unable to complete a driving simulator study due to simulator sickness with greater than 90% accuracy and that older participants had a greater likelihood of simulator sickness than younger participants. Possible explanations for increased symptoms experienced by older participants are discussed as well as implications for research ethics and simulator sickness prevention.
Age-related changes in thirst, salt appetite, and arterial blood pressure in response to aldosterone-dexamethasone combination in rats

This work examined the effects of age on daily water and sodium ingestion and cardiovascular responses to chronic administration of the mineralocorticoid, aldosterone (ALDO) either alone or together with the glucocorticoid, dexamethasone (DEX). Young (4 mo), adult (12 mo), and aged (30 mo) male Brown Norway rats were prepared for continuous telemetry recording of blood pressure (BP) and heart rate (HR). Baseline water and sodium (i.e., 0.3 M NaCl) intake, BP, and HR were established for 10 days. Then ALDO (60 μg/day sc) was infused alone, or together with DEX (2.5 or 20 μg/day sc), for another 10 days. Compared with baseline levels, ALDO stimulated comparable increases in daily saline intake at all ages. ALDO together with the higher dose of DEX (i.e., ALDO/DEX20) increased daily saline intake more than did ALDO, but less so in aged rats. Infusion of ALDO/DEX20 increased mean arterial pressure (MAP), and decreased HR, more than did infusion of ALDO. The changes in MAP in response to both treatments depended on age. For all ages, MAP and saline intake increased simultaneously during ALDO, while MAP always increased before saline intake did during ALDO/DEX20. Contrary to our predictions, MAP did not increase more in old rats in response to either treatment. We speculate that age-related declines in cardiovascular responses to glucocorticoids contributed to the attenuated increases in sodium intake in response to glucocorticoids that were observed in older animals.
A comparison of scientific and engineering criteria for Bayesian modelselection

Given a set of possible models for variables X and a set of possible parameters for each model, the Bayesian “estimate” of the probability distribution for X given observed data is obtained by averaging over the possible models and their parameters. An often-used approximation for this estimate is obtained by selecting a single model and averaging over its parameters. The approximation is useful because it is computationally efficient, and because it provides a model that facilitates understanding of the domain. A common criterion for model selection is the posterior probability of the model. Another criterion for model selection, proposed by San Martini and Spezzafari (1984), is the predictive performance of a model for the next observation to be seen. From the standpoint of domain understanding, both criteria are useful, because one identifies the model that is most likely, whereas the other identifies the model that is the best predictor of the next observation. To highlight the difference, we refer to the posterior-probability and alternative criteria as the scientific criterion (SC) and engineering criterion (EC), respectively. When we are interested in predicting the next observation, the model-averaged estimate is at least as good as that produced by EC, which itself is at least as good as the estimate produced by SC. We show experimentally that, for Bayesian-network models containing discrete variables only, the predictive performance of the model average can be significantly better than those of single models selected by either criterion, and that differences between models selected by the two criterion can be substantial.
The Effects of Eolian Sorting and Abrasion Upon the Shapes of Fine Quartz Sand Grains

ABSTRACT Grain-shape and surface-texture analyses were conducted on fine quartz sand grains from North Padre Island and the South Texas eolian sand sheet. The purpose was to determine the effects of eolian shape sorting and abrasion upon the shapes of eolian sand grains. Two conclusions are reached. The first is that the wind preferentially transports spherical, rounded sand grains, and this can result in the isolation and accumulation of such grains in an eolian deposit after a relatively short transport distance. The second is that eolian abrasion can greatly increase the roundness of sand grains during their transport over a distance of less than 160 km. Abrasion does not, however, produce any regular downwind change in sand-grain sphericity.