cssi/SciSciGPT-SciSciNet huggingface dataset:
Sex and risk in young women's tourist experiences: context, likelihood, and consequences.

Abstract This study offers an empirical application of the tripartite model of context, likelihood, and consequences for understanding risk in tourism among young women engaging in sexual risk-taking. Data, collected via an online survey (N = 853; mean age of 23.5 years), were analyzed using descriptive statistics, independent and paired samples t-tests, and exploratory factor analysis. The women identified eight to nine days long, rest and relaxation, sightseeing, and backpacking tourist experiences in tropical destinations and European countries as the ultimate settings for sex with a steady and casual sexual partner. In assessing the likelihood of engaging in sexual risk-taking, a distinct difference between reported moderate personal propensity and a higher evaluation of people's general proclivity was identified. Expected consequences were classified into three motivational/reward factors: Anonymous Experimentation, Safe Thrills and Empowerment, and Fun and Less Inhibition. Theoretical insights regarding sexual risk-taking in tourism and implications for related health promotion programs are discussed.
Heteranthery in Clarkia: pollen performance of dimorphic anthers contradicts expectations.

Author(s): Peach, Kristen; Mazer, Susan J | Abstract: Premise of the studyWild plant species that require the services of pollen-feeding insects for reliable pollination may evolve features that attract and reward their mutualistic partners. Heterantherous species have been proposed to exhibit a "division of labor" whereby "feeding anthers" (which produce pollen that may be consumed by an insect) are distinguished from "reproductive anthers" (which produce pollen more likely to contribute to reproduction). In some heterantherous species, including Clarkia unguiculata (Onagraceae), these two anther types differ with respect to stamen length, anther size, pollen production, and pollen color.MethodsThe primary goal of this study was to test one component of the "division of labor" hypothesis by comparing the performance of the pollen produced by each type of anther in C. unguiculata. To achieve this goal, under greenhouse conditions, we hand pollinated and assessed pollen performance (using epifluorescence microscopy) within ~228 flowers.Key resultsThe pollen produced by the two anther types differed significantly with respect to both stigma and style penetration. The inner series of anthers produce pollen with higher performance than the outer series of longer, dark red anthers.ConclusionsThese findings contradict previous descriptions of the genus, reporting that the inner diminutive series of anthers in Clarkia produce "abortive and nonfunctional" pollen. We outline the future research required to demonstrate the ecological function of heteranthery in this iconic wildflower group.
Rapid response to COVID-19: health informatics support for outbreak management in an academic health system.

Objective To describe the implementation of technological support important for optimizing clinical management of the COVID-19 pandemic. Materials and methods Our health system has confirmed prior and current cases of COVID-19. An Incident Command Center was established early in the crisis and helped identify electronic health record (EHR)-based tools to support clinical care. Results We outline the design and implementation of EHR-based rapid screening processes, laboratory testing, clinical decision support, reporting tools, and patient-facing technology related to COVID-19. Discussion The EHR is a useful tool to enable rapid deployment of standardized processes. UC San Diego Health built multiple COVID-19-specific tools to support outbreak management, including scripted triaging, electronic check-in, standard ordering and documentation, secure messaging, real-time data analytics, and telemedicine capabilities. Challenges included the need to frequently adjust build to meet rapidly evolving requirements, communication, and adoption, and to coordinate the needs of multiple stakeholders while maintaining high-quality, prepandemic medical care. Conclusion The EHR is an essential tool in supporting the clinical needs of a health system managing the COVID-19 pandemic.
Mitral Stenosis and Left Atrial Myxoma

The normal area of the mitral valve orifice is 4 to 6 cm2. Clinical symptoms of mitral stenosis are most likely to begin where the mitral orifice area is reduced to 1.5 cm2 or less, and severe symptomatic mitral stenosis is usually associated with narrowing of the orifice to 1 cm2 or less.
Do Two Wrongs Make a Right? Persistent Uncertainties Regarding Environmental Selenium-Mercury Interactions.

Mercury (Hg) is a pervasive environmental pollutant and contaminant of concern for both people and wildlife that has been a focus of environmental remediation efforts for decades. A growing body of...
Effects of fetal and maternal genotype on placentome morphology in sheep.

Both maternal and fetal genotypes contribute to conceptus development. The objective was to determine how placentome number, size, and type and fetal weight was influenced after reciprocal embryo transfer in Columbia and Romanov sheep. Reciprocal embryo transfer was conducted between Columbia and Romanov ewes where a single embryo was transferred into Romanov and Columbia recipients [Romanov embryo in a Romanov uterus (RinR, n = 9); Romanov embryo in a Columbia uterus (RinC, n = 7); Columbia embryo in a Columbia uterus (CinC, n = 8); Columbia embryo in a Romanov uterus (CinR, n = 4)]. On day 130 of gestation, fetuses were weighed and placentomes were morphologically typed, weighed, and measured. Regardless of maternal genotype, Romanov fetuses were smaller (P < 0.05) compared to Columbia fetuses. Moreover, CinC fetuses were larger (P < 0.05) than CinR fetuses. There was a tendency (P = 0.12) for a fetal by maternal genotype interaction on total placentome weight, but main effects were significant for fetal genotype (P = 0.04) and maternal genotype (P < 0.01). The number of Type A placentomes was greater than any other types. Type A placentomes had a greater (P < 0.05) contribution to total placentome weight within the Romanov uterus, or when associated with a Romanov fetus, than within the Columbia breed, in which placentome type was evenly distributed. The hypothesis that the Romanov uterus would limit the growth of a Columbia conceptus is accepted; however, the Romanov conceptus did not experience augmented growth when transferred into a Columbia uterus as predicted.
Correlation Between Gastrocnemius Tightness and Heel Pain Severity in Plantar Fasciitis

Background:It is known that there is an association between gastrocnemius tightness and plantar fasciitis, but this has never been quantified. The purpose of the study was to determine the correlat...
Analysis of tumor-infiltrating NK and T cells highlights IL-15 stimulation and TIGIT blockade as a combination immunotherapy strategy for soft tissue sarcomas

Purpose Given the unmet need for novel immunotherapy in soft tissue sarcoma (STS), we sought to characterize the phenotype and function of intratumoral natural killer (NK) and T cells to identify novel strategies to augment tumor-infiltrating lymphocyte (TIL) function. Experimental design Using prospectively collected specimens from dogs and humans with sarcomas, archived specimens, and The Cancer Genome Atlas (TCGA) data, we evaluated blood and tumor NK and T cell phenotype and function and correlated those with outcome. We then assessed the effects of interleukin 15 (IL-15) stimulation on both NK and T cell activation and TIGIT upregulation. Finally, we evaluated cytotoxic effects of IL-15 combined with TIGIT blockade using a novel anti-TIGIT antibody. Results TILs were strongly associated with survival outcome in both archived tissue and TCGA, but higher TIL content was also associated with higher TIGIT expression. Compared with blood, intratumoral NK and T cells showed significantly higher expression of both activation and exhaustion markers, in particular TIGIT. Ex vivo stimulation of blood and tumor NK and T cells from patients with STS with IL-15 further increased both activation and exhaustion markers, including TIGIT. Dogs with metastatic osteosarcoma receiving inhaled IL-15 also exhibited upregulation of activation markers and TIGIT. Ex vivo, combined IL-15 and TIGIT blockade using STS blood and tumor specimens significantly increased cytotoxicity against STS targets. Conclusion Intratumoral NK and T cells are prognostic in STS, but their activation is marked by significant upregulation of TIGIT. Our data suggest that combined IL-15 and TIGIT blockade may be a promising clinical strategy in STS.
Effective Erythropoiesis from Human iPSC-Derived RBC in Immunodeficient Mice

Transfusion of red blood cells (RBCs) was the earliest developed form of cell therapy and is still a highly effective life-saving treatment for many patients. Induced pluripotent stem cells (iPSC) can differentiate into RBCs (iPSC-RBCs) and may provide a novel source for blood transfusion and a cellular model for erythroid differentiation. Here we developed a murine model to investigate the in vivo properties of human iPSC-RBCs. Human iPSC were generated from peripheral blood mononuclear cells of healthy donors by transfection of plasmids containing OCT4, SOX2, MYC, KLF4 and BCL-XL genes. iPSC lines expressed TRA-1-60, SSEA4 and Nanog markers, and showed a normal karyotype. iPSCs were induced to differentiate along the erythroid lineage using a 3-stage culture system requiring 33 days. At the end of the culture period, iPSC-RBCs were CD34-CD235a+CD41+CD43+CD71low; about 10% of cells were enucleated (CD235a+DRAQ5-). iPSC-RBCs were harvested and transfused into immunodeficient NSG mice which had been pretreated with clodronate liposomes and cobra venom factor (CL/CVF). CL/CVF treatment of NSG mice markedly promoted the survival of transfused human iPSC-RBC in vivo, which could be detected with anti-human CD235a antibodies for at least 7 days, although the numbers progressively decreased with time. Interestingly, a large number of transfused iPSC-derived cells homed to bone marrow of NSG mice. In NSG mice that were repetitively treated with CL/CVF every 3 days, nucleated iPSC-derived cells were still detectable in the bone marrow 4 weeks after transfusion. Furthermore, at 3 weeks after transfusion, human iPSC-RBCs reappeared in the peripheral circulation. These circulating iPSC-RBCs were > 90% enucleated and were present at levels more than 4-fold higher than at 1 hour after transfusion. These results suggest that iPSC-RBCs which homed to the bone marrow of NSG mice retained the capability to complete differentiation into enucleated erythrocytes and egress the bone marrow into the peripheral blood. The results offer a new model using human peripheral blood iPSC and CL/CVF-treated NSG mice to investigate the development of human erythroid cells in vivo. Disclosures Jajosky: Biconcavity Inc.: Other: CEO and partial owner; BioMarin Pharmaceuticals: Current equity holder in publicly-traded company; Magenta Therapeutics: Current equity holder in publicly-traded company.
A Crystal Structure-Based Eigentransformation and its Work-Conjugate Material Stress

In the abstract of his 1970 paper, Eshelby stated: “The force on a dislocation or point defect, as understood in solid-state physics, and the crack extension force of fracture mechanics are examples of quantities which measure the rate at which the total energy of a physical system varies as some kind of departure from uniformity within it changes its configuration.” He then went on to demonstrate that the elastic energy-momentum tensor proves to be a useful tool in calculating such forces. The ‘forces’ turn out to be the appropriate traction vectors associated with the energy-momentum (stress) tensor. It is therefore natural and perhaps even fundamental to look for the ’strain tensor’ that can be paired with the ’stress tensor’ to form work. The ’strain rate’ would then be that some kind of departure from uniformity within a physical system. In this paper, we examine the configurational changes brought about by atomic diffusion in a nonuniform alloy crystal. The transformation from a reference, single-parameter simple cubic cell to a six-parameter alloy crystal cell, called the eigentransformation, is identified as the needed kinematic tensor.
The Bankruptcy Crisis

Americans love records, statistics, and amazing numbers. Home runs, rushing yardage, presidential-approval ratings, smoking-related deaths, and murder rates-all offer great material for attention-grabbing headlines. In 1996, the bankruptcy system stepped into the spotlight by supplying an attention-grabbing number of its own: more than a mnillion bankruptcies were filed in a single year.' The filing rate had increased sharply over the previous year, but this was nothing new. Rather, the magic of "one million" made bankruptcy a newsworthy subject to be covered in virtually every newspaper, news magazine, and national television news program during the year. Bankruptcy, like baseball and publicopinion polls, had become a sport of numbers, perhaps not widely understood, but the subject of breathless reports, as the benchmark of a million-plus consumer filings was passed. The million-filing mark might have been a short-lived subject for the popular press but for one factor: the filing rate gave the credit industry an opportunity to plead its case publicly that Congress should significantly restructure the bankruptcy laws. The fact that one million families filed for bankruptcy signified a crisis, namely that it is too easy to file for bankruptcy. The credit industry also offered the blueprint for a solution: make it more difficult for families to file for bankruptcy. Business bankruptcy filings are not part of the alleged crisis. Perhaps a robust economy or the increasing sophistication of parties to craft out-of-court workouts has kept the business bankruptcy system out of the news. Business bankruptcy cases account for only about four percent of all bankruptcy filings and the
Mutual Legal Assistance and Extradition: Human Rights Implications

Crime in China has taken on an increasingly transnational dimension. In part this is due to the cross-border nature of certain crimes, such as smuggling and drug trafficking. In other situations, the crimes are committed solely within China but the suspects flee, sometimes with the alleged fruits of the crime in hand. In either case, there is a need for cooperation between Chinese and foreign law enforcement and judicial authorities. This cooperation comes in many forms. China’s Ministry of Justice lists three major avenues for cooperation in criminal matters: 1) bilateral judicial-assistance treaties, 2) multilateral conventions with provisions on judicial assistance and extradition, and 3) cooperation in individual cases with countries that have not concluded a treaty with China. This article focuses on bilateral treaties and their relevance to the protection of human rights, including issues presented by politicized prosecutions, limits on criminal defendants’ access to evidence, and cases where criminal defendants may face the death penalty in China.
Risk aversion in decision models

Risk aversion has formed an integral part in most applied decision models under uncertainty, where the latter is generated by a probabilistic mechanism. This mechanism is not completely known, so that the environment under which decisions are to be made is random. However, the source of randomness may differ from one application to another, hence the decision-making response may vary. For example, in micro-economic models, consumer’s or producer’s response behavior is analyzed under conditions of price or cost parameter uncertainty and this behavior is compared with the case when there is no uncertainty. In engineering systems having a number of channels, the reliability levels may vary between channels and the noise elements may vary: the decision problem is one of maximizing the system reliability. In quality control, a sample inspection plan seeks to determine an acceptable quality level (AQL) of a product lot by minimizing the cost of making wrong decisions, where the latter involves producer’s risk (α) and consumer’s risk (β). The probability that a sampling plan will reject AQL is called the producer’s risk a i.e. the Type I error, whereas the probability that the plan will accept fraction-defective levels (FDL) is called consumer’s riskβ i.e. the Type II error. Usually, if the lot quality is equal to or better than AQL quality, p a is equal to or greater than (1 — α), where p a denotes the probability of acceptance which is usually 0.95 i.e. α = 0.05. Similarly, if the lot quality is equal to or worse than FDL quality, p a is equal to or less thanβ, the Type II decision error and p a is usually 0.10.
Statistics Metadata: Linear Regression Analysis

This paper deals with statistics metadata in the context of estimating the parameters and analysis of data, using statistical linear regression analysis techniques. Statistics metadata consists of complex data objects and the rules for manipulating them. The paper includes a brief outline of statistical linear estimation and establishes the important role that statistics metadata can play in real time linear regression analysis. The paper also discusses the structure of the statistics metadata for range-select-query, link-query, insert-query, delete-query and update-query. Statistics metadata locking is also discussed.
PRML (partial response maximum likelihood) simulator with nonlinearity compensated channel model

As linear recording density of optical discs increases, the channel non-linearity grows larger. And narrowing of track pitch also makes the read-out signals affected by large crosstalk from adjacent tracks. These non-linearity and crosstalk degrade the performance of the disc read-out systems. So we need to design equalizers and detecting methods - especially MLSD(Maximum Likelihood Sequence Detector) - considering those deteriorating factors.
Options for the disposal of unwanted donations.

Abstract Donations of biomedical books and journals frequently duplicate the holdings of a receiving library. A decision must then be made concerning the distribution of the material to other libraries that may need it. What options are available to the librarian? Are many volumes of valuable material destroyed each year because libraries lack the necessary staff, space, or money to distribute donated materials? Are libraries restricted in choice of methods for distribution or unaware of available options? A survey questionnaire was mailed to 150 health sciences libraries in the spring of 1988 to determine the various methods used to dispose of unwanted gift materials. A total of 113 responses was received (75% return rate). This paper reports the results and discusses some of the creative methods used by receiving libraries to place unneeded materials. Statistical comparisons are included for the methods used by academic, hospital, and other types of health sciences libraries.
Principles and a Decision-Making Process for Accountable Partnership Engagement to Create Healthy Food and Active Living Environments in the United States

Objective: Voluntary engagement strategies are used by national governments, industry and non-governmental organizations to address obesity and non-communicable diseases (NCDs) through research, po...
Medium access control in a network of ad hoc mobile nodes with heterogeneous power capabilities

MAC layer protocols for wireless ad hoc networks typically assume that the network is homogeneous with respect to the transmit power capability of individual nodes in the network. The IEEE 802.11 MAC protocol has been popular for use in ad hoc networks. We investigate the performance of this protocol when it is used in a network with nodes that transmit at various power levels. We show that overall throughput is lower than the throughput of a network in which all nodes transmit at identical power levels. In addition, low power nodes have a disadvantage in accessing the medium due to higher levels of interference from the high power nodes. We consider propagating the control messages generated by a node wishing to initiate communication to distant nodes so that they may forbear transmissions for some time, thereby allowing clear access to the initiating node. We find that the overhead incurred due to the additional message transmissions outweighs the potential gain achieved by propagating these messages. This indicates that the signalling mechanism used in the IEEE 802.11 standard or the variants thereof are not sufficient to alleviate the loss in throughput and the lack of fairness engendered by networks that are heterogeneous with regard to the transmit power capabilities of individual nodes.
Mammogram iterative pompeiu-hausdorff registration algorithm

Accurate mammogram registration is vital to future breast cancer research. In order to detect changes over time and/or bilateral asymmetry, computer aided detection algorithms must first be able to accurately align two mammogram images. The Mammogram Iterative Pompeiu-Hausdorff Registration Algorithm (MIPHRA) is a novel process designed to accurately register two mammogram images. MIPHRA is built upon a new technique for efficiently minimizing the Pompeiu-Hausdorff distance between two images (or point sets) over rigid body motion. A recent study comprised of 100 bilateral mammogram pairs revealed that MIPHRA offers increased accuracy and efficiency over current rigid-body mammogram registration techniques, such as mutual information.
α-Oxoketene dithioacetals: Versatile substrates for 1,3-carbonyl transpositions

Abstract A two step procedure for the conversion of α-oxoketene dithioacetals to β-substituted α, β-unsaturated thioesters or acids is described. The overall transformation represents a 1,3-carbonyl transposition in which the original ketone carbonyl emerges as the carbonyl of an acid or thioester. The resulting thioesters and acids constitute versatile acylating reagents in accord with established procedures.
A new neurological focus in neonatal intensive care

Advances in the care of high-risk newborn babies have contributed to reduced mortality rates for premature and term births, but the surviving neonates often have increased neurological morbidity. Therapies aimed at reducing the neurological sequelae of birth asphyxia at term have brought hypothermia treatment into the realm of standard care. However, this therapy does not provide complete protection from neurological complications and a need to develop adjunctive therapies for improved neurological outcomes remains. In addition, the care of neurologically impaired neonates, regardless of their gestational age, clearly requires a focused approach to avoid further injury to the brain and to optimize the neurodevelopmental status of the newborn baby at discharge from hospital. This focused approach includes, but is not limited to, monitoring of the patient's brain with amplitude-integrated and continuous video EEG, prevention of infection, developmentally appropriate care, and family support. Provision of dedicated neurocritical care to newborn babies requires a collaborative effort between neonatologists and neurologists, training in neonatal neurology for nurses and future generations of care providers, and the recognition that common neonatal medical problems and intensive care have an effect on the developing brain.
Yttrium oxide based three dimensional metamaterials for visible light cloaking

Metamaterial with negative refractive index is the key phenomenon behind the concept of a cloaking device to hide an object from light in visible spectrum. Metamaterials made of two and three dimensional lattices of periodically placed electromagnetic resonant cells can achieve absorption and propagation of incident electromagnetic radiation as confined electromagnetic fields confined to a waveguide as surface plasmon polaritons, which can be used for shielding an object from in-tune electromagnetic radiation. The periodicity and dimensions of resonant cavity determine the frequency, which are very small as compared to the wavelength of incident light. Till now the phenomena have been demonstrated only for lights in near infrared spectrum. Recent advancements in fabrication techniques have made it possible to fabricate array of three dimensional nanostructures with cross-sections as small as 25 nm that are required for negative refractive index for wavelengths in visible light spectrum of 400-700 nm and for wider view angle. Two types of metamaterial designs, three dimensional concentric split ring and fishnet, are considered. Three dimensional structures consisted of metal-dielectric-metal stacks. The metal is silver and dielectric is yttrium oxide, other than conventional materials such as FR4 and Duroid. High κ dielectric and high refractive index as well as large crystal symmetry of Yttrium oxide has been investigated as encapsulating medium. Dependence of refractive index on wavelength and bandwidth of negative refractive index region are analyzed for application towards cloaking from light in visible spectrum.
New Model for Schistosome Granuloma Formation using a Soluble Egg Antigen and Bentonite Particles

INJECTION of purified Schistosoma mansoni eggs into mice results in granuloma formation1, and it has been shown that egg antigen is gradually released to phagocytes which accumulate around the eggs and engage in antigen sequestration and destruction in situ2. Schistosome granuloma formation as seen in the infected host is a complex immunological response probably involving several synergistic mechanisms3. In experimental anamnestic granulomas of mice, the augmented and accelerated cell response is mediated by delayed hypersensitivity4 and is partly suppressed by immunosuppressive drugs, neonatal thymectomy, ALS (antilymphocyte serum) and X-irradiation5–8; it is slightly inhibited by ellagic acid9. Soluble egg antigens have been obtained from Schistosome eggs by phosphate buffered saline (PBS) extraction and ultra-centrifugation which enhance granuloma formation around schistosome eggs in mice and induce dermal reactivity in the mouse footpad (unpublished work of D. L. Boros and K. S. Warren). This material is currently being analysed immunochemically.
avr‐15 encodes a chloride channel subunit that mediates inhibitory glutamatergic neurotransmission and ivermectin sensitivity in Caenorhabditis elegans

Ivermectin is a widely used anthelmintic drug whose nematocidal mechanism is incompletely understood. We have used Caenorhabditis elegans as a model system to understand ivermectin9s effects. We found that the M3 neurons of the C.elegans pharynx form fast inhibitory glutamatergic neuromuscular synapses. avr‐15 , a gene that confers ivermectin sensitivity on worms, is necessary postsynaptically for a functional M3 synapse and for the hyperpolarizing effect of glutamate on pharyngeal muscle. avr‐15 encodes two alternatively spliced channel subunits that share ligand binding and transmembrane domains and are members of the family of glutamate‐gated chloride channel subunits. An avr‐15 ‐encoded subunit forms a homomeric channel that is ivermectin‐sensitive and glutamate‐gated. These results indicate that: (i) an ivermectin‐sensitive chloride channel mediates fast inhibitory glutamatergic neuromuscular transmission; and (ii) a nematocidal property of ivermectin derives from its activity as an agonist of glutamate‐gated chloride channels in essential excitable cells such as those of the pharynx.
Tonic and myoclonic seizures in lennox-gastaut syndrome mistaken as complex partial seizures

Abstract Five children with the Lennox-Gastaut syndrome had seizures consisting of staring, mental status change, and automatic movements associated with subtle repetitive motor jerks. Based on the clinical history and observations, the seizures were classified as complex partial seizures. Because of poor responses to treatment directed toward complex partial seizures, time-locked video/EEG evaluations were performed and correctly identified the seizures as clusters of generalized myoclonic or tonic seizures. These observations demonstrate that patients with Lennox-Gastaut syndrome may develop series of brief, repeated tonic or myoclonic seizures in which the behavioral phenomena are more pronounced than the motor activity. Successful treatment of seizures in patients with Lennox-Gastaut syndrome may require careful differentiation between seizure types.
Effects of Individual Differences and Situational Features on Age Differences in Mindless Reading

OBJECTIVE Mindless reading occurs when an individual shifts their attention away from the text and toward other off-task thoughts. This study examined whether previously reported age-related declines in mindless reading episodes are due primarily to (a) situational features related to the text itself (e.g., text genre or interest in the text) and/or (b) individual differences in cognitive ability. METHOD Participants read 2 texts written in different genres but about the same topic. During reading, they were randomly probed to indicate whether they were on-task or mind-wandering. They also indicated their perceptions regarding the interest and difficulty of the text, and completed a battery of cognitive ability measures. RESULTS The results showed that (a) text genre may engender some age differences in mindless reading and (b) greater age and perceived interest in the text were each uniquely predictive of reduced mindless reading for both text genres. Individual differences in cognitive abilities (e.g., working memory, vocabulary) did not account for additional significant variance in mindless reading after interest and age were taken into account. DISCUSSION Our findings are discussed in terms of implications for age differences in lapses of attention during reading and predictors of mind-wandering generally.
The Physical Biochemistry and Molecular Genetics of Sulfate Activation

AbstractThis article is an overview of current research in the area of sulfate activation. Emphasis is placed on presenting unresolved issues in an appropriate context for critical evaluation by the reader. The energetics of sulfate activation is reevaluated in light of recent findings that demonstrate that the synthesis of activated sulfate is thermodynamically driven by GTP hydrolysis. The structural and functional bases of this GTPase activation are discussed in detail. The bonding and hydrolysis of the high-energy, phosphoric-sulfuric acid anhydride bond of activated sulfate are presented along with an analysis of the importance of the divalent cation and pyrophosphate protonation in the equilibria governing activated sulfate formation. The molecular genetics of sulfate assimilation in prokaryotes is reviewed with an emphasis on the regulation of the pathway. Recent discoveries connecting sulfate activation to plant/microbe symbiogenesis are presented, as are several examples of the importance of acti...
Heterosynaptic correlates of long-term potentiation induction in hippocampal CA3 neurons.

Abstract Previous studies have demonstrated that tetanization of hippocampal mossy fibers induces a long-term potentiation of non-tetanized (heterosynaptic) non-mossy fiber afferents (Schaffer collateral/commissural and fimbrial fibers). Tetanization of these non-mossy fiber afferents, in contrast, does not induce mossy fiber long-term potentiation, but induces a long-term depression of mossy fiber responses (Bradler and Barrionuevo, Synapse 4, 132–142, 1989). The synaptic activity necessary to evoke these heterosynaptic alterations of efficacy is not known. Specifically, the dependence of heterosynaptic efficacy on the activation of N-methyl- d -aspartate receptors has not been assessed. In addition, the capability of different afferents to CA3 neurons to support alterations in heterosynaptic efficacy remains largely unknown. In the present study, heterosynaptic alterations of efficacy in the rat did not require the activation of N-methyl- d -aspartate receptors. Mossy fibers supported N-methyl- d -aspartate receptor-indepedent heterosynaptic long-term depression, and N-methyl- d -aspartate receptor-independent long-term potentiation. In contrast, non-mossy fiber afferents expressed N-methyl- d -aspartate receptor-independent heterosynaptic long-term potentiation induced by a mossy fiber tetanus, and an x N-methyl- d -aspartate receptor-independent long-term depression, in addition to N-methyl- d -aspartate receptor-dependent homosynaptic long-term potentiation. The possibility that N--methyl- d -aspartate receptor activity in non-tetanized afferents is necessary for heterosynaptic long-term potentiation induction is discussed. Heterosynaptic long-term depression was induced in the absence of homosynaptic long-term potentiation, suggesting that these concomitant forms of synaptic plasticity rely on different mechanisms.
Brain Morphometry with Multiecho MPRAGE

In brain morphometry studies using magnetic resonance imaging, several scans with a range of contrasts are often collected. The images may be locally distorted due to imperfect shimming in regions where magnetic susceptibility changes rapidly, and all scans may not be distorted in the same way. In multispectral studies it is critical that the edges of structures align precisely across all contrasts. The MPRAGE (MPR) sequence has excellent contrast properties for cortical segmentation, while multiecho FLASH (MEF) provides better contrast for segmentation of subcortical structures. Here, a multiecho version of the MPRAGE (MEMPR) is evaluated using SIENA and FreeSurfer. The higher bandwidth of the MEMPR results in reduced distortions that match those of the MEF while the SNR is recovered by combining the echoes. Accurate automatic identification of cortex and thickness estimation is frustrated by the presence of dura adjacent to regions such as the entorhinal cortex. In the typical MPRAGE protocol, dura and cortex are approximately isointense. However, dura has substantially smaller T2* than cortex. This information is represented in the multiple echoes of the MEMPR. An algorithm is described for correcting cortical thickness using T2*. It is shown that with MEMPR, SIENA generates more reliable percentage brain volume changes and FreeSurfer generates more reliable cortical models. The regions where cortical thickness is affected by dura are shown. MEMPR did not substantially improve subcortical segmentations. Since acquisition time is the same for MEMPR as for MPRAGE, and it has better distortion properties and additional T2* information, MEMPR is recommended for morphometry studies.
Total nutrient admixtures appear safer than lipid emulsion alone as regards microbial contamination : Growth properties of microbial pathogens at room temperature

Background The extraordinary growth properties of most microorganisms in 10% and 20% lipid emulsions has led to the Centers for Disease Control and Prevention recommendation that if lipids are given through an i.v. line, the administration set should be replaced every 24 hours rather than the usual 72-hour interval used for crystalloid solutions, including those used for conventional total parenteral nutrition. For nearly 15 years, parenteral alimentation has been given as a total nutrient admixture (TNA), with the glucose, amino acids, and lipid mixed within the same bag and infused continuously over 24 hours. Methods We prospectively studied in a representative TNA (17.6% glucose, 5% amino acids, 4% lipid; pH 5.6, osmolality 1778) and in a control solution, 5% dextrose-in-water (D5%/W), the growth properties at 4, 25, and 35 degrees C of three isolates each of Staphylococcus epidermidis, Staphylococcus aureus, Enterobacter cloacae, Klebsiella oxytoca, Serratia marcescens, Acinetobacter calcoaceticus, Stenotrophomonas maltophilia, Pseudomonas aeruginosa, Burkholderia cepacia, Flavobacterium spp, and Candida albicans, and two isolates of Staphylococcus saprophyticus, the species that are most likely to contaminate TNA during preparation or administration and that have been implicated in >95% of all outbreaks and sporadic cases of nosocomial bloodstream infections traced to contaminated parenteral admixtures reported in the world literature. Results Growth in TNA at 25 and 35 degrees C occurred with only two species, C. albicans and S. saprophyticus, and only after 24 to 48 hours; D5%/W allowed growth at 25 degrees C of two gram-negative species, S. marcescens and B. cepacia. Conclusions We conclude that TNA is a poor growth medium for most nosocomial pathogens and is no better than D5%/W. The need to replace administration sets every 24 hours with TNA should be reconsidered and ideally be studied in a prospective randomized trial.
Life cycle assessment of high temperature electrolysis for hydrogen production via nuclear energy

Abstract A life cycle assessment (LCA) of one proposed method of hydrogen production—the high temperature electrolysis of water vapor—is presented in this paper. High temperature electrolysis offers an advantage of higher energy efficiency over the conventional low-temperature alkaline electrolysis due to reduced cell potential and consequent electrical energy requirements. The primary energy source for the electrolysis will be advanced nuclear reactors operating at temperatures corresponding to those required for the high temperature electrolysis. The LCA examines the environmental impact of the combined advanced nuclear-high temperature electrolysis plant, focusing upon quantifying the emissions of carbon dioxide, sulfur dioxide, and nitrogen oxides per kilogram of hydrogen produced. The results are presented in terms of the global warming potential (GWP) and the acidification potential (AP) of the system. The GWP for the system is 2000 g carbon dioxide equivalent and the AP, 0.15 g equivalents of hydrogen ion equivalent per kilogram of hydrogen produced. The GWP and AP of this process are one-sixth and one-third, respectively, of those for the hydrogen production by steam reforming of natural gas, and are comparable to producing hydrogen from wind- or hydro-electricity powered conventional electrolysis.
Mobility enhancement due to charge trapping & defect generation: Physics of self-compensated BTI

Threshold voltage VT of a transistor degrades with time both due to the formation of defects at the oxide/Si interface, as well as charge trapping into bulk defects - a phenomenon commonly known as Bias Temperature Instability (BTI). However, we have shown earlier that with appropriate mobility vs. vertical effective electric field characteristics, transistor's drivability (i.e., drain current) can be made far less sensitive to the NBTI-induced threshold voltage degradation ΔV T , than previously presumed. Higher steepness of the mobility-field characteristics results in an increase in mobility due to interface defects, which can self-compensate the effect of ΔV T on drain current. In this paper, for the first time we analyze the additional effect of PBTI-induced ΔV T in NMOS transistor parameters and show that mobility at constant gate voltage always increases with PBTI, irrespective of the mobility-field steepness. Therefore, self-compensation for PBTI is even more pronounced compared to NBTI. Next, we demonstrate the consequence of self-compensation via an intuitive analysis in simple digital circuits and show that lifetime of digital ICs increases dramatically once we incorporate the effect of self-compensation by using appropriate sign for mobility variation at constant gate voltage. This might in turn reduce the requirement of different circuit level optimization techniques, currently employed to manage transistor variabilities. Finally, we establish the importance of flatter transfer characteristics for self-compensation, which can be obtained through advanced CMOS technologies.
Preparative Purification of a High-Mannose TypeN-Glycan from Soy Bean Agglutinin by Hydrazinolysis and Tyrosinamide Derivatization

Abstract The N-linked oligosaccharide from soy bean agglutinin (Man 9 ) was isolated on a preparative scale following derivatization with Boc-tyrosine. The procedure utilized preparative hydrazinolysis to release the oligosaccharide and yielded multi-μmol quantities of Boc-tyrosine-Man 9 which was characterized by 1 H NMR and ES-MS.
The effect of microbial contamination and pH changes in storage solutions during in vitro assays of bonding agents

A study of pH changes in, and microbial colonization of, storage solutions being utilized during an in vitro evaluation of luting agent solubility has been made. Microbial growth in storage solutions was observed to occur at as high as 105 colony-forming units (cfu)/mL after seven days' incubation. A strong time-dependent inverse correlation between pH and cfu was found, with the pH dropping to as low as 5.3 (p<0.01). Decreases in pH were not found in presterilized control samples (p<0.05). Further, it was demonstrated that presterilization with ethylene oxide or the addition of respiratory inhibitors prevented both microbial colonization and the pH drop when compared with controls (p<0.001). These data suggest that studies of dental materials which include incubations in various fluids should be controlled for the potential effects of micro-organisms and their effect on pH.
Role of Fas-mediated cell death in the regulation of immune responses.

Abstract Interaction of the cell-surface molecule Fas (CD95 APO-1) with its specific ligand triggers apoptotic death of T and B lymphocytes. This pathway is important for eliminating self-reactive lymphocytes and thus preventing autoimmunity. Fas is also involved in controlling injurious lymphocyte reactions in immunologically ‘privileged’ tissues, and may provide a strategy for reducing graft rejection.
Power analysis for quantitative trait locus mapping in populations derived by multiple backcrosses

Populations derived by multiple backcrosses are potentially useful for quantitative trait locus (QTL) mapping studies. Comparisons of relative power to detect QTL using populations derived by multiple back-crosses are needed to make decisions when mapping projects are initiated. The objective of this study was to theoretically compare the power to detect QTL in populations derived by multiple backcrosses relative to mapping in a recombinant inbred population of equal size. Backcrossing results in a reduction in genetic variance with each generation and also results in an increasing frequency of the recurrent parent marker genotype. The relevant outcome for QTL mapping is a reduction in genetic variance to partition between marker genotype classes and increasing unbalance of the number of individuals contributing to the mean of the marker genotypes. Both of these factors lead to a decrease in the power to detect a QTL as the number of backcross generations increases. Experimental error was held constant with the populations compared. From a theoretical standpoint, backcross-derived populations offer few advantages for QTL detection. If, however, a backcrossing approach is the most efficient method to achieve a desired breeding objective and if QTL detection is an objective of equal or less importance, backcross-derived populations are a reasonable approach to QTL detection.
Methods of computing effects of secondary fluid injection on rocket engine performance

Analytical evaluation of secondary flow injection effects on rocket engine performance including cold flow and simulated hot flow data
The PTEN–PI3K pathway: of feedbacks and cross-talks

The tumor suppressor PTEN was originally identified as a negative regulator of the phosphoinositide 3-kinase (PI3K) signaling, a main regulator of cell growth, metabolism and survival. Yet this function of PTEN is extremely relevant for its tumor-suppressive ability, albeit the recent characterization of many PI3K-independent tumor-suppressive activities. PI3K-mediated PIP(3) production leads to the activation of the canonical AKT-mTORC1 pathway. The implications of this signaling cascade in health and disease have been underscored by the high number of regulators within the pathway whose alterations give rise to different malignancies, including familiar syndromes, metabolic dysfunctions and cancer. Moreover, PI3K is tightly buffered at multiple levels by downstream components, which have turned this signaling pathway literally upside down. PI3K and its downstream components in turn cross-talk with a number of other pathways, thereby leading to a complex network of signals that may have dramatic consequences when perturbed. Here, we review the current status of the PTEN-PI3K signaling pathway with special emphasis on the most recent data on targets and regulation of the PTEN-PI3K axis. This provides novel provocative therapeutic implications based on the targeted modulation of PI3K-cross-talking signals.
Expression of ectonucleotide pyrophosphate phosphodiesterase and peroxisome proliferator activated receptor gamma in morbidly obese patients.

Background Recently, two genes, peroxisome proliferator activated receptor gamma (PPARγ) and ectonucleotide pyrophosphate phosphodiesterase (ENPP1), have been localized and associated with diabetes and obesity. This report hypothesizes that there is a correlation between the genetic expression of ENPP1 and PPARγ from gastrointestinal tissue and body mass index (BMI).
TEACHING JOB INDEPENDENCE AND FLEXIBILITY TO MENTALLY RETARDED STUDENTS THROUGH THE USE OF A SELF-CONTROL PACKAGE

We examined mentally retarded individuals' use of picture cues and self-monitoring to initiate a series of tasks of varying type and order. Four severely to moderately retarded high school students participating in a vocational training program were trained to use a picture-cue system. The system consisted of photographs of vocational tasks that were inserted in the assigned order in a photoalbum sheet; self-management was accomplished by marking off each photo after its corresponding task was completed. Students were assigned seven tasks from a pool of 13 each day. Results indicated that the students quickly learned to use the picture-cue system to change tasks throughout their workday without trainer prompts and that performance was maintained as trainer feedback and presence were decreased. At the end of the study, two students who were exposed to novel photographs were able to initiate independently after only minimal training, suggesting that the use of the picture-cue system had become a generalized skill.
Electron Temperature Dependence of the Recombination Coefficient in Pure Helium

The phenomenon of "afterglow quenching" is employed to determine the electron temperature dependence of the electron-ion recombination coefficient in plasmas produced in purified helium (estimated impurity 1:${10}^{9}$). The total visible light intensity was studied as a function of electron temperature. By means of 1.5% bandwidth filters, the light intensity of two helium spectral lines (5876 A and 3888 A) were also investigated. It is found that the recombination coefficient for highly purified helium varies as the minus three-halves power of the electron temperature from 300\ifmmode^\circ\else\textdegree\fi{} to \ensuremath{\sim}1500\ifmmode^\circ\else\textdegree\fi{}K at electron densities of \ensuremath{\sim}${10}^{11}$/cc, and gas pressures from 12.6 to 30.3 mm Hg. At 300\ifmmode^\circ\else\textdegree\fi{}K (temperature determined from collision frequency measurements), the recombination coefficient in purified helium is found to be (8.9\ifmmode\pm\else\textpm\fi{}0.5)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}9}$ ${\mathrm{cm}}^{3}$/ion sec. It is found that both the recombination coefficient and its electron temperature dependence were strongly influenced by the addition of controlled amounts (2\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}4}$ to 1300\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}4}$%) of neon impurities.