cssi/SciSciGPT-SciSciNet huggingface dataset:
Influence of frame size and body condition score on performance of Brahman cattle.

The effects of frame size (FS) and body condition score (BCS) on performance of Brahman cows were evaluated using records collected from 1984 to 1994 at the Subtropical Agricultural Research Station, Brooksville, Florida. Age at puberty (AP), calving rate (CR), calving date (CD), survival rate (SR), weaning rate (WR), birth weight (BWT), weaning weight (WWT), preweaning ADG, and kilograms of calf produced per cow exposed (PPC) were obtained from first- (n = 215), second- (n = 130), and third or greater-parity (n = 267) dams. Based on hip height at 18 mo of age, heifers were assigned to three FS groups: small (115 to 126 cm), medium (127 to 133 cm), or large (134 to 145 cm). Small and medium FS heifers attained puberty at younger (P < .05) ages (633.2 ± 12.3 and 626.4 ± 12.0 d) than large FS heifers (672.3 ± 17.1 d). Calving rate in large FS second-parity dams was 27% less (P < .05) than in small and medium FS dams. In third or greater-parity dams, CR was greater (P < .05) for small FS cows than for medium and large FS cows. Across the three parity groups, CR improved with increasing BCS. Except for the first-parity dams, animals with better fall BCS calved earlier (P < .05). In first-parity dams, SR was less (P < .01) in large (47.9 ± 11.0%) than in small (80.7 ± 5.2%) and medium (83.4 ± 4.7%) FS groups. Weaning rates of large FS first- and second-parity dams were less (P < .05) than those of small and medium FS dams. Second-parity dams with BCS 3 had lower (P < .05) WR than dams with BCS 4 and 5. Within first- and third or greater-parity dams, BWT of calves born to small FS cows were the lightest, and those born to large FS dams were the heaviest; those born to medium FS dams were intermediate (P < .05). In second-parity dams, BWT of calves of large FS dams were greater (P < .05) than those of small and medium FS dams. In first- parity dams, calves weaned by small FS cows had lower (P < .05) WWT than those weaned by higher FS cows. In the third or greater-parity group, large FS dams weaned heavier calves (P < .05) than other dams. In all parity groups of dams, calves out of large FS cows had greater ADG (P < .05) than those from small and me- dium FS cows. In first-parity dams, PPC was compara- ble between small and medium FS dams, but both tended to be greater (P < .10) than PPC of large FS dams. Small and medium FS females reached puberty at an earlier age, calved earlier, and had greater calv- ing, survival, and weaning rates, as well as greater kilograms of calf produced per cow exposed than the large FS females. As the large FS cows matured, they seemed to have overcome the negative effects imposed by FS that were observed at younger ages. Their perfor- mance traits were generally all comparable to those of smaller cows once they had reached maturity.
Gender Differences in the Epidemiology and Treatment of Anxiety Disorders

Women are more likely than men to develop anxiety disorders. Yet, relatively few studies have investigated whether women with anxiety disorders have characteristics that are distinct from those of men with the same disorders. The cause of the enhanced vulnerability to anxiety for women remains largely undetermined. Recent data suggest that female reproductive hormones and related cycles may play an important role. In addition to etiologic functions, reproductive hormones may substantially influence the clinical course of preexisting anxiety conditions in women. Psychotropic medications are more likely to be prescribed to women, and gender differences have been identified in the pharmacokinetics of psychotropic medication. Yet, relatively few systematic data are available concerning the potential clinical relevance or possible treatment implications of gender differences in the treatment of women with anxiety disorders. This article reviews the unique characteristics of primary anxiety disorders in women, summarizes the neurobiological effects associated with estrogen and progesterone, discusses gender differences in medication metabolism and the potential relevance of these differences in the pharmacologic management of women with anxiety disorders, and reviews issues specific to women (e.g., hormone therapy, oral contraceptives, menstrual cycle, pregnancy, lactation) that may impact treatment with psychotropic medication.
The Electric Brain and Behavioral Medicine

This chapter explores the use of electrophysiological methods in behavioral medicine. Studies are reviewed that involve recording the electroencephalogram (EEG), event-related potential (ERP), or evoked potential. Electrophysiological methods have been applied in examining disease: cardiovascular disease, diabetes and neuroendocrine disorder, cancer, immunological disorders, chronic pain, respiratory diseases, and kidney and blood diseases. In addition, electrophysiological methods have been used to examine the effects of hormone treatment, stress, biofeedback and to examine health behaviors. In the review of these studies, the following four conclusions were drawn. First of all, it appears that electrophysiological methods are rarely used in behavioral medicine research. Second, in the studies we identified, electrophysiological methods were used to examine cognitive function rather than affective and motivational states. Third, since EEG and ERP measures are sensitive both to biological and psychological factors, it is necessary for investigators to take a biopsychosocial approach in examining health and disease. Finally, in the studies reviewed in this chapter, EEG and ERP measures have predominantly been used as markers rather than to examine processes in health and disease.
The limits of system improvement through liquid diagonal routing of interconnects

An interconnect distribution for a system utilizing liquid diagonal routing is rigorously derived. Using the distribution in conjunction with a wiring layer assignment algorithm, the limits of clock frequency and area improvements are quantified as a function of wiring efficiency, the ratio of utilized wiring area to those available. A liquid-routed system with only a 28% wiring efficiency is equivalent to an orthogonally routed system with a 40% wiring efficiency. A wiring efficiency of a liquid-routed system below 28% results in an inferior design in regards to clock frequency and/or required metal resources. If a 40% wiring efficiency is maintained, however, the power-constrained clock frequency can be increased by 38% with a 69% reduction in area, or the power-density-constrained area can be reduced by 75% with a 47% reduction in power. Liquid diagonal routing promises improvements to both area and clock frequency if the wiring efficiency is maintained above roughly 30%.
Parental involvement in adolescent romantic relationships: patterns and correlates

This study examined dimensions of mothers’ and fathers’ involvement in adolescents’ romantic relationships when offspring were age 17. Using cluster analysis, parents from 105 White, working and middle class families were classified as positively involved, negatively involved, or autonomy-oriented with respect to their adolescents’ romantic relationships. Patterns of parental involvement were generally not associated with parent–offspring relationship quality at about adolescent age 13, but earlier parent–offspring relationship quality moderated the associations between parental involvement and adolescent romantic experiences at about age 18. Positive parent–offspring relationship quality buffered the effects of negative parental involvement, whereas poorer parent–offspring relationship quality was a more adaptive context for adolescents of autonomy-oriented parents. Discussion focuses on the importance of parenting practices in adolescent romantic relationships and the emotional climate of parent–offspring relationships as a developmental context for those practices.
TU‐A‐9A‐01: A Precise Deformable Image Registration System Using Feature‐Based Irregular Meshes

Purpose: To develop a deformable image registration system using irregular meshes generated based on image features. Finer meshes are generated at organ or tissue boundaries so that higher deformation resolution is achieved with limited number of control points. Methods: This deformable image registration system consists of two parts: a finite element modeling system and a GPU-based registration system. The finite element modeling system is used to generate irregular meshes for the entire body or region of interest without segmentation. This system uses a Laplacian of Gaussion operator to extract features such as boundaries between organs and tissues. The placement of control points (vertices) of meshes is optimized based on feature intensities. The registration framework uses elastic energy as regularity and guarantees the final deformation vector field to be diffeomorphic. This system has been compared with registration algorithms based on regular meshes or voxels (Demons). The comparison is performed on XCAT digital phantom data and patient data. Results: Both XCAT male phantom and female phantom were used. Two respiratory phases were treated as floating and fix images for every phantom. Similarity measures were performed for image intensity and displacement vector field (DVF) for four sets of testing data with three types of deformation algorithms (irregular mesh, regular grid, and voxel). It clearly shows that the voxel-based Demons algorithm leads to slightly better images. However, the DVF results show that mesh-based algorithms behave much better. Compared with regular meshes, the irregular mesh we proposed leads to much faster convergence and converge to better results. The calculation is accelerated by GPU cards and a typical registration of patient data could be completed in about 1 minute. Conclusion: The feature-based irregular meshing method provides a fast and accurate deformable image registration. This research is supported by CPRIT individual investigator award RP110329 and Varian research grant.
Increases in cytosolic Ca2+ are not required for abscisic acid-inhibition of inward K+ currents in guard cells of Vicia faba L.

The inward K+ channels (IKin) of guard cells are inhibited upon application of abscisic acid (ABA). It has been postulated that IKin inhibition requires an elevation in cytosolic free Ca2+ levels ([Ca2+]c) because: (i) experimental increases in [Ca2+] c can mimic the ABA effect, and; (ii) ABA can trigger an elevation of [Ca2+]c in guard cells. However, not all guard cells respond to ABA with a [Ca2+]c increase, and the magnitude of the increases that do occur is variable. Therefore, an obligate role for Ca2+ in the regulation of downstream effectors of ABA response, such as the IKin channels, remains in question. In this study, we developed a methodology for simultaneous patch clamping and confocal ratiometric Ca2+ imaging of Vicia faba L. guard-cell protoplasts. This allowed us to directly assess the relationship between ABA-induced changes in [Ca2+]c and IKin inhibition. In the presence of extracellular Ca2+, the extent of [Ca2+]c elevation correlated with the extent of IKin inhibition. However, upon chelation of either extracellular Ca2+, [Ca2+]c, or both, extracellular Ca2+ and [Ca2+]c, [Ca2+]c elevation did not occur in response to ABA yet IKin currents were still strongly inhibited. These data illustrate that Ca2+-independent regulation is involved in ABA-inhibition of stomatal opening processes.
ATP depletion causes translational immobilization of cell surface transferrin receptors in K562 cells

We have used quantitative fluorescence microscopy and fluorescence photobleaching recovery to examine the role of metabolic energy in the translational movement of transferrin receptors in the plasma membrane of K562 erythroleukemia cells. Cellular ATP depletion caused a significant decrease in the translational mobility of cell surface transferrin receptors and a significant increase in the number of receptors on the cell surface. ATP repletion restored receptor translational mobility and cell surface expression to control values. Inhibition of ATP hydrolases by orthovanadate also immobilized cell surface transferrin receptors and altered cell surface receptor expression, in a concentration-dependent manner. Vanadate-induced changes in receptor mobility and cell surface expression were reversible upon washing out the drug. Cellular ATP depletion did not affect the translational mobility of plasma membrane glycophorins or a fluorescent phospholipid analogue. We conclude that the translational movement of cell surface transferrin receptors specifically requires metabolic energy and ATP hydrolysis. © 1996 Wiley-Liss, Inc.
“We Talk about Life”—KTCK, The Ticket, and the Influence of Guy Talk on Sports-Talk Radio

KTCK, “the Ticket,” in Dallas is a prime example of a sports-talk station whose format has evolved into “guy talk.” The station is the object of imitation in the sports-talk community, having reportedly earned $33 million in 2006. “The Ticket is a great radio station; there's no denying they do a wonderful job,” the program director of KILT-AM in Houston, Bill Van Rysdam says. Sports-talk stations across the country have learned that “guy talk” is the “ticket” for higher ratings and greater profits.
Penalized Estimation of Free-Knot Splines

Abstract Polynomial splines are often used in statistical regression models for smooth response functions. When the number and location of the knots are optimized, the approximating power of the spline is improved and the model is nonparametric with locally determined smoothness. However, finding the optimal knot locations is an historically difficult problem. We present a new estimation approach that improves computational properties by penalizing coalescing knots. The resulting estimator is easier to compute than the unpenalized estimates of knot positions, eliminates unnecessary “corners” in the fitted curve, and in simulation studies, shows no increase in the loss. A number of GCV and AIC type criteria for choosing the number of knots are evaluated via simulation.
Granular Dynamics Simulation on Multiple GPUs Using Domain Decomposition

This paper describes the software infrastructure needed to enable massive multi-body simulation using multiple GPUs. Utilizing a domain decomposition approach, a large system made up of billions of bodies can be split into self-contained subdomains which are then transferred to different GPUs and solved in parallel. Parallelism is enabled on multiple levels, first on the CPU through OpenMP and secondly on the GPU through NVIDIA CUDA (Compute Unified Device Architecture). This heterogeneous software infrastructure can be extended to networks of computers using MPI (Message Passing Interface) as each subdomain is self-contained. This paper will discuss the implementation of the spatial subdivision algorithm used for subdomain creation along with the algorithms used for collision detection and constraint solution.Copyright © 2012 by ASME
Formaldehyde: A Reagent for Simultaneous Protection of Heterocyclic NH and Activation of Alternative Locations to Electrophilic Attack. Part II. A New Synthetic Method for the 5(3)-Substitution of N-Unsubstituted Pyrazoles☆

Abstract N-Unsubstituted pyrazole 1 is readily converted into 5-substituted [tautomeric with 3-substituted 8] derivatives 2 in moderate to good overall yields in a one-pot sequence, using formaldehyde both for N-protection and to mediate lithiation at the 5-position. The dilithiohemiaminals 5 react with electrophiles at the pyrazole 5-position to give 5-substituted 1-lithioxymethylpyrazoles 6 which undergo smooth dehydroxymethylation under mild conditions (acid hydrolysis or silica gel) to give N-unsubstituted 5(3)-substituted pyrazoles.
Morphologic and Molecular Characterization of a Demodex (Acari: Demodicidae) Species from White-Tailed Deer (Odocoileus virginianus)

Demodex mites, although usually nonpathogenic, can cause a wide range of dermatological lesions ranging from mild skin irritation and alopecia to severe furunculosis. Recently, a case of demodicosis from a white-tailed deer (Odocoileus virginianus) revealed a Demodex species morphologically distinct from Demodex odocoilei. All life cycle stages were considerably larger than D. odocoilei and although similar in size to D. kutzeri and D. acutipes from European cervids, numerous morphometrics distinguished the four species. Adult males and females were and μm in length, respectively. Ova, larva, and nymphs measured , , and μm in length, respectively. For phylogenetic analyses, a portion of the 18S rRNA gene was amplified and sequenced from samples of the WTD Demodex sp., two Demodex samples from domestic dogs, and Demodex ursi from a black bear. Phylogenetic analyses indicated that the WTD Demodex was most similar to D. musculi from laboratory mice. A partial sequence from D. ursi was identical to the WTD Demodex sequence; however, these two species can be differentiated morphologically. This paper describes a second Demodex species from white-tailed deer and indicates that 18S rRNA is useful for phylogenetic analysis of most Demodex species, but two morphologically distinct species had identical partial sequences. Additional gene targets should be investigated for phylogenetic and parasite-host association studies.
Effect of Left Ventricular Assist Device Infection on Post-transplant Outcomes

Background In this study, we sought to confirm which types of device-related infections impact bridge-to-transplant rates. We also aimed to determine the effect of device-related infections on post-transplant survival and post-transplant infection. Methods We retrospectively reviewed paper and electronic medical records for 149 patients undergoing left ventricular assist device (LVAD) implantation as a bridge to transplantation at the Columbia Presbyterian Medical Center between 2000 and 2006. The primary outcome measures were survival to transplantation, post-transplant infection and post-transplant survival. Results Patients with sepsis were less likely to be successfully bridged to cardiac transplantation (7 of 22 vs 103 of 127, 31.8% vs 81.1%, p = 0.01). However, if transplanted, their survival rates at 1 year were not decreased (6 of 7 vs 85 of 103, 85.7% vs 82.5%, p = 1.00). No other pre-transplant device-related infection affected post-transplant survival at 1 year (22 of 27 vs 69 of 83, 81.5% vs 83.1%, p = 1.00). Pre-transplant drive-line infections predicted post-transplant infection in former drive-line or pocket sites (11 of 16 vs 14 of 94, 68.8% vs 14.9%, p = 0.01) and increased overall post-transplant hospital length of stay (16 vs 19 days, p = 0.04). They did not, however, affect post-transplant survival at 1 year (22 of 25 vs 69 of 85, 88% vs 81.2%, p = 0.56). Conclusions Although survival to transplantation was diminished in LVAD patients with sepsis, if successfully transplanted, post-transplant survival was unaffected. Patients with local device infections and signs of early sepsis may warrant evaluation for urgent transplantation. A pre-transplant drive-line infection was associated with post-transplant infection in either the former pocket or drive-line site, and increased overall length of stay, but it did not decrease post-transplant survival.
Freeze-fracture of neurons in nucleus magnocellularis of the chick

4- to 8-day-old chicks were used to examine the ultrastructure of end bulbs and neurons of nucleus magnocellularis by freeze-fracture and thin section techniques. Both normal animals and animals deafferented by removal of the basilar papilla were used to describe the pre- and postsynaptic membranes of these neurons. Postsynaptic membrane specializations similar to those described in rodents were found in normal and deafferented chicks. In the presynaptic end bulb there was an immediate cessation of endocytotic vesicle formation after deafferentation. There was also a shift in the preferential fracture plane from the presynaptic to postsynaptic membranes 48-72 h after basilar papilla removal. These results indicate that the ultrastructure of this synaptic complex is comparable to that seen in mammals.
The X-linked Mental Retardation Protein OPHN1 Interacts with Homer1b/c to Control Spine Endocytic Zone Positioning and Expression of Synaptic Potentiation

At glutamatergic synapses, local endocytic recycling of AMPA receptors (AMPARs) is important for the supply of a mobile pool of AMPARs required for synaptic potentiation. This local recycling of AMPARs critically relies on the presence of an endocytic zone (EZ) near the postsynaptic density (PSD). The precise mechanisms that couple the EZ to the PSD still remain largely elusive, with the large GTPase Dynamin-3 and the multimeric PSD adaptor protein Homer1 as the two main players identified. Here, we demonstrate that a physical interaction between the X-linked mental retardation protein oligophrenin-1 (OPHN1) and Homer1b/c is crucial for the positioning of the EZ adjacent to the PSD, and present evidence that this interaction is important for OPHN1's role in controlling activity-dependent strengthening of excitatory synapses in the rat hippocampus. Disruption of the OPHN1-Homer1b/c interaction causes a displacement of EZs from the PSD, along with impaired AMPAR recycling and reduced AMPAR accumulation at synapses, in both basal conditions and conditions that can induce synaptic potentiation. Together, our findings unveil a novel role for OPHN1 as an interaction partner of Homer1b/c in spine EZ positioning, and provide new mechanistic insight into how genetic deficits in OPHN1 can lead to impaired synapse maturation and plasticity.
Enjoyment as a preventive of depressive affect

Previous work suggests two mechanisms whereby finding enjoyment in life decreases the likelihood of depressive affect: (a) enjoyment counteracts depressive affect and (b) failure to find enjoyment is itself a stimulus for depressive affect. The present study, based on interviews with 2168 adults in two communities, yields findings which are consistent with the proposition that satisfaction with major life areas is a factor in finding enjoyment in life, thereby a factor in avoiding depressive affect and thereby a factor in avoiding psycho-physiologic problems. Thus the present study provides a measure of support for the proposition that finding enjoyment in life reduces the likelihood of depressive affect and for the corollary of this proposition, that social, psychological, and other factors in the enjoyment of life are thereby also factors in depressive affect and its consequences.
Silica Hydride Surfaces: Versatile Separation Media for Chromatographic and Electrophoretic Analyses

Abstract Silica hydride, where Si‐H groups replace 95% of the silanols on the surface, is rapidly being developed as a chromatographic support material for HPLC. This chemical structure results in changes of fundamental properties compared to ordinary silica, as well as the bonded stationary phases produced by the further modification of the hydride surface. Several unique chromatographic capabilities of hydride based phases are described, as well as some general application areas where these bonded materials may be used in preference to, or have advantages not available from current commercial stationary phases. The fabrication, properties and applications of etched chemically modified capillaries for electrophoretic analysis are also reviewed. The etching process creates a surface that is fundamentally different in comparison to a bare fused silica capillary. The new surface matrix produces altered electroosmotic flow properties and is more compatible with basic and biological compounds. After chemical ...
Young children's sensitivity to direct and indirect request structure

Effects of request structure and listener characteristics on young children's compliance with requests were examined in two experi ments. In Experiment 1, an adult used direct (imperative) requests (e.g., 'Give me ...'/'What is ... ?'), indirect embedded requests (e.g., 'Can you give me ... ?'/`Can you tell me ... ?'), and hint requests (e.g., 'The water is spilling ...'/`I wonder what ...') for action and information. The requests were used with 3- and 5-year- olds (10 at each age) in structured play interactions. Five-year-olds complied with all request forms more often than 3-year-olds. Within action requests, both groups complied with the embedded form most often, followed by the direct then hint forms. Within information requests, they complied with the direct form most often, followed by embedded then hint forms. In Experiment 2, syntactically simple and complex direct and embedded forms were used with 4-year-olds grouped for tested language comprehension ability. The 15 low-ability children complie...
Carrier Mediated Uptake of Deoxyguanosine in Rat Liver Mitochondria

It has been known for a number of years that mitochondria contain enzymes important for the synthesis of DNA. A distinct mitochondrial deoxyguanosine kinase was first documented by Gower etal. (1) in calf thymus. Mitochondrial deoxycytidine/deoxythymidine kinase (2) was demonstrated in blast cells of leukemia patients and HeLa mitochondria contain a deoxythymidine kinase (3). Mouse, human and chick mitochondria possess a deoxypyrimidine kinase (3). A recent report by Fabianowska-Majewska and Greger (4) shows that rat liver mitochondria contain deoxythymidine, deoxcytidine, deoxyadenosine and deoxyguanosine kinase activities, however few details regarding these activities were reported.
Diode-pumped 2- and 3-um solid state lasers

Broadly tunable cw laser emission is demonstrated at room temperature in the 1.85 - 2.15 micrometers and 2.20 - 2.45 micrometers regions from Tm:YALO solid-state laser with 795 nm diode laser pumping. Also efficient cw laser operation at room temperature is demonstrated from the Er3+ in a garnet host at 2.8 microns, which is resonantly pumped with the 970 nm diode laser, resulting in a laser slope efficiency of 36%.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A comparison of statistical methods for prenatal screening for Down syndrome

Currently, prenatal screening for Down Syndrome (DS) uses the mother's age as well as three biochemical markers for risk prediction. Risk calculations for the biochemical markers use a quadratic discriminant function. In this paper we compare several classification procedures to quadratic discrimination methods for biochemical-based DS risk prediction, based on data from a prospective multicentre prenatal screening study. We investigate alternative methods including linear discriminant methods, logistic regression methods, neural network methods, and classification and regression-tree methods. Several experiments are performed, and in each experiment resampling methods are used to create training and testing data sets. The procedures on the test data set are summarized by the area under their receiver operating characteristic curves. In each experiment this process is repeated 500 times and then the classification procedures are compared. We find that several methods are superior to the currently used quadratic discriminant method for risk estimation for these data. The implications of these results for prenatal screening programs are discussed.
Management of type 2 diabetes: evolving strategies for the treatment of patients with type 2 diabetes

The prevalence of type 2 diabetes continues to increase at an alarming rate around the world, with even more people being affected by prediabetes. Although the pathogenesis and long-term complications of type 2 diabetes are fairly well known, its treatment has remained challenging, with only half of the patients achieving the recommended hemoglobin A1c target. This narrative review explores the pathogenetic rationale for the treatment of type 2 diabetes, with the view of fostering better understanding of the evolving treatment modalities. The diagnostic criteria including the role of hemoglobin A1c in the diagnosis of diabetes are discussed. Due attention is given to the different therapeutic maneuvers and their utility in the management of the diabetic patient. The evidence supporting the role of exercise, medical nutrition therapy, glucose monitoring, and antiobesity measures including pharmacotherapy and bariatric surgery is discussed. The controversial subject of optimum glycemic control in hospitalized and ambulatory patients is discussed in detail. An update of the available pharmacologic options for the management of type 2 diabetes is provided with particular emphasis on newer and emerging modalities. Special attention has been given to the initiation of insulin therapy in patients with type 2 diabetes, with explanation of the pathophysiologic basis for insulin therapy in the ambulatory diabetic patient. A review of the evidence supporting the efficacy of the different preventive measures is also provided.
Nanocluster Size Evolution Studied by Mass Spectrometry in Room Temperature Au25(SR)18 Synthesis

We show that MALDI mass spectrometry, suitable for mixtures, is an indispensable tool in probing the mechanism of nanocluster synthesis enabling positive identification of nanoclusters. The size evolution of the mixture of larger clusters (Au(102), Au(68), Au(38)) to form highly monodisperse Au(25) nanoclusters is demonstrated and probably includes the participation of Au(I) thiolate. The size evolution via structural reconstruction of the larger cores such as 38, approximately 44, 68, and 102 to a Au(25) nanocluster has been discussed.
Dissecting T cell receptor nanocluster signaling

The early steps of T cell activation involve the spatial rearrangement of T cell receptors (TCR) and associated molecules into small nanoclusters at the interface with the antigen presenting cell. Recent evidence suggests they are actively signaling, however their role in signal initiation and propagation is still unclear. To mechanically control the agonist MCC-MHC per TCR cluster we use microcorrals of fluid supported lipid bilayer with a confined number of MCC-MHC and correspondingly bound TCR. T cell activation (measured by calcium flux) on these microcorrals is significantly reduced at low MCC-MHC concentrations, compared to cells off them. T cell activation depends not on the overall number of agonist-MHC present, but on their number per microcorral. At least two MCC-MHCs per corral are required to trigger T cell calcium flux. Cells that can cluster even more MCC-MHC per TCR cluster do not exhibit higher signaling. This result provides an extension to the heterodimer hypothesis, by which a direct complex between agonist-MHC-TCR and co-agonist-MHC-TCR is the functional signaling unit. It confirms that two MCC-MHC-TCR are required and suggests that they are sufficient for TCR nanocluster signaling.
Enhanced four-wave mixing by use of frequency-shifted optical waves in photorefractive BaTiO3.

We present theory and experiments to show that the efficiency of four-wave mixing in photorefractive materials can be enhanced by use of optical waves of slightly different frequencies. The optimum frequency shift scales inversely with the response time of the material. We show that the \ensuremath{\sim}1-Hz frequency shift previously observed in the output of a self-pumped phase conjugator that used photorefractive BaTi${\mathrm{O}}_{3}$ is the result of this inherent property of four-wave mixing.
An electron microscopic analysis of gliogenesis in rat optic nerves.

The development of neuroglia has been studied in rat optic nerves with the electron and light microscopes. The main findings of this investigation are as follows:
A study of the neutron-rich isotopes near A = 100 by means of the (t, p) reaction

Abstract The (t, p) reaction has been used to study the nuclides 102 Mo, 106 Ru and 112 Pd, all of which are two neutrons beyond the stable isotopes. A (t, p) spectrum of the 102 Ru(t, p) 104 Ru process was also obtained. The incident triton energy was 15 MeV in all cases and a magnetic spectrograph was used for momentum analysis of the reaction protons with an energy resolution of ≈ 20 keV FWHM resulting. Differential cross sections were measured for many transitions and spin and parity assignments have been made for a number of states. Examination of the results indicates that only 102 Mo shows characteristics of being a transitional nucleus between regions of different nuclear shape whereas the other nuclei studied appear to be in regions where the coupling scheme changes more slowly. The first 2 + state of 102 Mo is markedly lower in excitation energy than in the lighter isotopes and a low-lying 0 + state is excited with large intensity relative to the ground state. The present results agree with previous results from the Berkeley group on the decay of fission fragments and in a qualitative way support several recent theoretical predictions.
Drug and sexual risk in four men who have sex with men populations: evidence for a sustained HIV epidemic in New York City

The objective of this article was to examine drug and sexual risk in four salient groups of men who have sex with men (MSM) in New York City (NYC): (1) nonhomeless young MSM (YMSM), (2) homeless YMSM, (3) adult MSM Speed users, and (4) HIV-positive “POZ Party” MSM. Lifetime and current exposure to drugs, drug injection, and selected drug-sex interactions are highlighted in each group. Data derive from recently completed field-based, ethnoepidemiological studies that used venue-oriented/targeted sampling and semistructured interviews. Across all four groups, findings show that both drug and sexual risk remain prevalent in the MSM population in NYC. This is especially troubling given the already high background prevalence of HIV and other sexually transmitted diseases in NYC and the widespread suffering and death already wrought by HIV/AIDS among MSM. These findings suggest that available public health interventions today are, in many respects, failing to reach, engage, and affect critical risk groups within the NYC MSM population.
The use of concerns theory in inservice training for computer education

Abstract The introduction of computers in the schools represents a dramatic change. Bentzen [1], Goodlad [2], and Hall [3] have documented the important role of the individual in the change process. Our research focused on the personal dimensions of the change process, and on teacher concerns about using microcomputers in the classroom. Eighteen teachers at the senior high school level volunteered to complete the Stages of Concern Questionnaire that reliably yields data on seven distinct stages of concerns (Hall et al. [4]). Based on their SoCQ profiles, three “users” and three “non-users” were interviewed to determine the present and projected uses of computers in teaching. This data base was used to design a set of inservice activities that over a three day period for 15 hours, produced a significant change in teachers' concerns towards microcomputers. A change model assuming a person-level orientation to an innovation is a promising approach to be used in inservicing.
Multiple fibroblast growth factors support growth of the ureteric bud but have different effects on branching morphogenesis.

Abstract Together with glial-derived neurotrophic factor (GDNF), soluble factors present in a metanephric mesenchyme (MM) cell conditioned medium (BSN-CM) are necessary to induce branching morphogenesis of the isolated ureteric bud (UB) in vitro (Proc. Natl. Acad. Sci. USA 96 (1999) 7330). Several lines of evidence are presented here in support of a modulating role for fibroblast growth factors (FGFs) in this process. RT-PCR revealed the expression of two FGF receptors, FGFR1(IIIc) and FGFR2(IIIb), in isolated embryonic day 13 rat UBs, which by indirect immunofluorescence displayed a uniform distribution. Rat kidney organ culture experiments in the presence of a soluble FGFR2(IIIb) chimera or a neutralizing antibody to FGF7 suggested an important contribution of FGFs other than FGF7 to the branching program. Several FGFs, including FGF1, FGF2, FGF7 and FGF10, in combination with GDNF and BSN-CM were found to affect growth and branching of the isolated UB, albeit with very different effects. FGF1 and FGF7 were at extreme ends of the spectrum, with FGF10 (more FGF1-like) and FGF2 (more FGF7-like) falling in between. FGF1 induced the formation of elongated UB branching stalks with distinct proliferative ampullary tips, whereas FGF7 induced amorphous buds displaying nonselective proliferation with little distinction between stalks and ampullae. Electron microscopic examination demonstrated that FGF1 treatment induced cytoskeletal organization, intercellular junctions and lumens along the stalk portion of the developing tubules, while the ampullary regions contained ‘less differentiated’ cells with an abundant secretory apparatus. In contrast, FGF7-induced UBs displayed this ‘less differentiated’ morphology regardless of position on the structure and were virtually indistinguishable from FGF1-induced ampullae. Consistent with this, GeneChip array analysis (employing a novel nanogram-scale assay consisting of two rounds of amplification and in vitro transcription for analyzing small quantities of RNA) revealed that FGF7-induced UBs expressed more markers of cell proliferation than FGF1, which caused the UB to express cytoskeletal proteins, extracellular matrix proteins, and at least one integrin, some of which may be important in UB branch elongation. Thus, while the various FGFs examined all support UB growth, FGF1 and FGF10 appear to be more important for branching and branch elongation, and may thus play a role in determination of nephron number and patterning in the developing kidney. These in vitro data may help to explain results from knockout and transgenic studies and suggest how different FGFs may, together with GDNF and other factor(s) secreted by MM cells, regulate branching morphogenesis of the UB by their relative effects on its growth, branching and branch elongation and differentiation, thereby affecting patterning in the developing kidney.
The incorporation of S35O4 into bile of chicks.

SummaryChicks utilize sulfate-S35 to synthesize taurine. Dietary cholic acid, taurine or both are associated with increased volumes of bile fluid. Cholic acid feeding enhances sulfate-S35 incorporation into the bile while taurine decreases such reactions.
Diffusible and bound actin in nuclei of xenopus laevis oocytes

Abstract Several criteria have been used to identify actin in hand-isolated nuclei of Xenopus laevis oocytes; these include co-migration with actin on SDS-polyacrylamide gels, immunological cross-reactivity with antiserum against actin, binding to DNAase I and peptide mapping on SDS gels. The use of hand-isolated nuclei precludes the possibility of contamination from cytoplasmic actin or the leakage of significant amounts of actin from nuclei during isolation. Actin constitutes roughly 6% of the total nuclear protein. Approximately 75% of the actin is diffusible under the conditions of nuclear isolation used. About 25%, however, is stably associated with an insoluble nuclear gel, in which chromosomes, nucleoli and other nuclear granules are embedded. Actin is the single most prominent component of the nuclear gel, comprising roughly 16% of the total protein of the complex. The possible significance of diffusible and bound actin in these nuclei is discussed.
Impacts of Mobile Computing on Student Learning in the University: A Comparison of Course Assessment Data

This study focuses on the impact of wireless, mobile computing tools on student assessment outcomes. In a campus-wide wireless, mobile computing environment at an upper Midwest university, an empir...
HIGH FIDELITY FETAL RADIOELECTROCARDIOGRAPHY.

Abstract 1. 1. A new method for obtaining fetal electrocardiograms of superior quality has been described. 2. 2. Our technic employs a dual channel radioelectrocardiograph, a low pass filter, a miniaturized microamplifier electrode assembly, and a silver oxide conductive jelly developed in this laboratory. 3. 3. Fetal electrocardiograms of diagnostic quality were obtained in 47 of 50 consecutive patients studied during active labor. 4. 4. The tracings taken with this system have a stable baseline and no somatic tremor even during an active uterine contraction. The fetal QRS complexes are shown in excellent detail, and their voltage equals or exceeds that of the maternal.
Precipitation induced by ion beam thinning

SUMMARY Ion beam thinning of aluminium–lithium alloys under conventional conditions required to produce electron microscope thin foils is shown to induce significant microstructural changes, equivalent to heating the specimen in excess of ∼400 K.
Effects of Modeling on Attitudes and Perceptions of Preservice Special Education Teachers

The current study examined the effect of modeling instructional strategies in an introductory class for preservice special education teuchers. Participants' attitudes toward various instructional strategies with regard to their own learning and their perceptions of instructional strategies to use with teaching students with exceptionalities were examined. Results indicated that attitudes and perceptions of preservice special educators were positively affected by the instructor's modeling of certain strategies.
Analysis of peptides from pigeon cerebrum: A comparison of sacrifice methods

Abstract BARRACO, R. A., M. S. ABEL AND D. M. TERRIAN. Analysis of peptides from pigeon cerebrum: A comparison of sacrifice methods . BRAIN RES. BULL. 3 (6) 645–653, 1978.—Peptides were extracted and fractionated from pigeon cerebrum and analyzed by thin-layer chromatography, polyacrylamide disc gel electrophoresis, and amino acid analysis. A highly consistent pattern of peptides in the 700–5000 molecular weight range was obtained from each cerebral sample. A comparison was also made between cerebral peptide patterns obtained from animals sacrificed by decapitation with those from animals sacrificed by microwave irradiation. Amino acid analysis of the peptide fraction from microwaved and decapitated animals revealed slight differences in the amount and incidence of various amino acids. These differences may be due to post-mortem proteolysis in the cerebra of decapitated pigeons prior to homogenization and freezing.
Varieties of chemical closure. Three kinds of coherence observed in chemical systems, and their relation to societal integration

: Covalent bonding within chemical molecules and the internal electronic structure of atoms involve closure of phase relations in electronic wave functions, as suggested de Broglie by many years ago. The structures of crystals involving positive and negative ions can be understood in terms of replication of unit cells that may be classified in terms of symmetry. The main principle involved in crystal symmetry can be understood by examining possible patterns in decorative borders. A more widely applicable type of chemical closure occurs in oscillating reactions (dissipative structures), in which an autocatalytic process is balanced by some exit reaction. As is the case for the other types of chemical coherence, the number of distinct types of oscillating reactions is rather small. Otherwise puzzling aspects of human social and organizational behavior may be clarified by analogy with chemical oscillating reactions.
Variational calculation of NMR relaxation of diffusing ions by impurity centers

The relaxation rate of a diffusing spin influenced by an impurity center is treated. We present both a qualitative scaling argument which can predict the dependence of the rate on various parameters and a variational principle which can be used to obtain a quantitative result accurate to within about 12% for a simple trial function. The methods should be useful for the study of NMR in fast ion conductors in situations, such as anistropic diffusion in a low-dimensional system or impurity-influenced diffusion rate, where exact solutions of a continuum diffusion equation with a sink are not obtainable. For example, we treat (i) the standard three-dimensional case with a ${r}^{\ensuremath{-}6}$ interaction and compare the simple variational calculation with the known exact result, and (ii) a quasi-one-dimensional system which has not previously been solved.
Correlation of resting electrocardiographic ST-T wave abnormalities with exercise thallium-201 stress testing in patients with known or suspected coronary artery disease

Abstract Resting ST-T wave abnormalities have been associated with an increased risk of adverse cardiac events. Because increased myocardial ischemia represents a possible mechanism for these abnormalities, this study sought to determine whether patients with resting ST-T have greater myocardium in jeopardy as evidenced by stress-induced thallium-201 perfusion abnormalities. One hundred thirty-two consecutive patients not taking digitalis were prospectively studied with combined symptom-limited exercise testing and quantitative thallium-201 imaging. Patients with (n = 43) versus without (n = 89) resting ST-T were older and more frequently had diabetes mellitus. No difference between the 2 groups was seen with respect to gender, cardiac medications, systemic hypertension, prior myocardial infarction, or coronary artery bypass surgery. The results of stress testing were similar for the 2 groups with respect to maximal heart rate, maximal blood pressure, and METs achieved. The mean depth of ST depression was similar in the 2 groups, although patients without resting ST-T were more likely to have upsloping ST depresssion, and had a shorter duration of ST depression after exercise. With use of an 11 segment model analysis of stress and rest planar thallium-201 scintigrams, patients with versus without resting ST-T had significantly more scan segments showing redistribution defects (1.1 ± 1.7 vs 0.5 ± 1.1; p = 0.03) and total (both redistribution and persistent) defects (2.5 ± 2.5 vs 1.3 ± 1.9; p = 0.002). The lung-heart ratios (normal
Primary photochemical processes in isolated reaction centers of Rhodopseudomonas viridis

Picosecond and nanosecond spectroscopic techniques have been used to study the primary electron transfer processes in reaction centers isolated from the photosynthetic bacterium Rhodopseudomonas viridis. Following flash excitation, the first excited singlet state (P*) of the bacteriochlorophyll complex (P) transfers an electron to an intermediate acceptor (I) in less than 20 ps. The radical pair state P+I-) subsequently transfers an electron to another acceptor (X) in about 230 ps. There is an additional step of unknown significance exhibiting 35 ps kinetics. P+ subsequently extracts an electron from a cytochrome, with a time constant of about 270 ns. At low redox potential (X reduced before the flash), the state P+I- (or PF) lives approx. 15 ns. It decays, in part, into a longer lived state (PR), which appears to be a triplet state. State PR decays with an exponential time of approx. 55 microseconds. After continuous illumination at low redox potential (I and X both reduced), excitation with an 8-ps flash produces absorption changes reflecting the formation of the first excited singlet state, P*. Most of P* then decays with a time constant of 20 ps. The spectra of the absorbance changes associated with the conversion of P to P* or P+ support the view that P involves two or more interacting bacteriochlorophylls. The absorbance changes associated with the reduction of I to I- suggest that I is a bacteriopheophytin interacting strongly with one or more bacteriochlorophylls in the reaction center.