cssi/SciSciGPT-SciSciNet huggingface dataset:
Distinction between far- and near-ultraviolet light killing of recombinationless (recA) Salmonella typhimurium

Abstract Recombinationless ( rec ) mutants of Salmonella typhimurium are sensitive to visible and near-ultraviolet light. The effects are distinct from those produced by shorter wavelength far-ultraviolet, in the following ways: (1) DNA is rapidly degraded in recA mutants following far-ultraviolet exposure; it remains intact after inactivation by visible or near-ultraviolet light. (2) Pyrimidine dimers are formed by far-ultraviolet; they are not detected following visible and near-ultraviolet exposure. (3) DNA solutions protect rec cells from far-ultraviolet death, but not from visible and near-ultraviolet. (4) Phage multiply in recA cells killed by far-ultraviolet; they fail to multiply in visible and near-ultraviolet exposed cells. These differences between far-ultraviolet and visible and near-ultraviolet effects support the view that death of recA mutants by irradiation need not be followed by DNA degradation.
The effects of methylphenidate on the interactions of preschool ADHD children with their mothers.

Abstract The effects of two doses of methylphenidate (0.15 mg/kg b.i.d. and 0.50 mg/kg b.i.d.) on the interactions of 27 preschool attention deficit hyperactivity disordered (ADHD) children with their mothers were evaluated using a double-blind, placebo-controlled crossover design, in which each drug condition lasted 7 to 10 days. Results indicated few drug effects during free play at either dose of medication, except for a decrease in the mothers' use of commands during the low dose of medication. Attention deficit hyperactivity disordered children on high doses decreased their off-task and noncompliant behavior and significantly increased their rates of compliance as well as the length of sustained compliance with maternal commands.
The Three Domains of Disgust Scale: Factor Structure, Psychometric Properties, and Conceptual Limitations

This investigation examined the measurement properties of the Three Domains of Disgust Scale (TDDS). Principal components analysis in Study 1 (n = 206) revealed three factors of Pathogen, Sexual, and Moral Disgust that demonstrated excellent reliability, including test-retest over 12 weeks. Confirmatory factor analyses in Study 2 (n = 406) supported the three factors. Supportive evidence for the validity of the Pathogen and Sexual Disgust subscales was found in Study 1 and Study 2 with strong associations with disgust/contamination and weak associations with negative affect. However, the validity of the Moral Disgust subscale was limited. Study 3 (n = 200) showed that the TDDS subscales differentially related to personality traits. Study 4 (n = 47) provided evidence for the validity of the TDDS subscales in relation to multiple indices of disgust/contamination aversion in a select sample. Study 5 (n = 70) further highlighted limitations of the Moral Disgust subscale given the lack of a theoretically consistent association with moral attitudes. Lastly, Study 6 (n = 178) showed that responses on the Moral Disgust scale were more intense when anger was the response option compared with when disgust was the response option. The implications of these findings for the assessment of disgust are discussed.
Molecular Analysis of Murine Leukemia Cell Lines Resistant to 5,10-Dideazatetrahydrofolate Identifies Several Amino Acids Critical to the Function of Folylpolyglutamate Synthetase

Abstract Four L1210 murine leukemia cell lines resistant to 5,10-dideazatetrahydrofolate (DDATHF) and other folate analogs, but sensitive to continuous exposure to methotrexate, were developed by chemical mutagenesis followed by DDATHF selective pressure. Endogenous folate pools were modestly reduced but polyglutamate derivatives of DDATHF and ALIMTA (LY231514, MTA) were markedly decreased in these mutant cell lines. Membrane transport was not a factor in drug resistance; rather, folypolyglutamate synthetase (FPGS) activity was decreased by >98%. In each cell line, FPGS mRNA expression was unchanged but both alleles of the FPGS gene bore a point mutation in highly conserved domains of the coding region. Four mutations were in the predicted ATP-, folate-, and/or glutamate-binding sites of FPGS, and two others were clustered in a peptide predicted to be β sheet 5, based on the crystal structure of theLactobacillus casei enzyme. Transfection of cDNAs for three mutant enzymes into FPGS-null Chinese hamster ovary cells restored a reduced level of clonal growth, whereas a T339I mutant supported growth at a level comparable to that of the wild-type enzyme. The two mutations predicted to be in β sheet 5, and one in the loop between NH2- and COOH-terminal domains did not support cell growth. When sets of mutated cDNAs were co-transfected into FPGS-null cells to mimic the genotype of drug-selected resistant cells, clonal growth was restored. These results demonstrate for the first time that single amino acid substitutions in several critical regions of FPGS can cause marked resistance to tetrahydrofolate antimetabolites, while still allowing cell survival.
Inhibition of rat mammary microsomal oxidation of ethanol to acetaldehyde by plant polyphenols

We previously reported that the microsomal fraction from rat mammary tissue is able to oxidize ethanol to acetaldehyde, a mutagenic-carcinogenic metabolite, depending on the presence of NADPH and oxygen but not inhibited by carbon monoxide or other cytochrome P450 inhibitors. The process was strongly inhibited by diphenyleneiodonium, a known inhibitor of NADPH oxidase, and by nordihydroguaiaretic acid, an inhibitor of lipoxygenases. This led us to suggest that both enzymes could be involved. With the purpose of identifying natural compounds present in food with the ability to decrease the production of acetaldehyde in mammary tissue, in the present studies, several plant polyphenols having inhibitory effects on lipoxygenases and of antioxidant nature were tested as potential inhibitors of the rat mammary tissue microsomal pathway of ethanol oxidation. We included in the present screening study 32 polyphenols having ready availability and that were also tested against the rat mammary tissue cytosolic metab...
Stereoselective high-performance liquid chromatographic assay with fluorometric detection for the isomers of mivacurium in human plasma.

A high-performance liquid chromatographic assay with fluorometric detection was developed for the analysis of the stereoisomers of mivacurium, a new short-acting neuromuscular blocker, in plasma. The isomers were isolated from plasma by solid-phase extraction with C18 and anion-exchange cartridges. The extracts were chromatographed on a LiChrosphere 60 RP Select B column (125 mm × 4.6 mm I.D.) using a mobile phase of acetonitrile—water (4:6, v/v) containing 0.005 M octanesulfonic acid. The fluorescence excitation and emission wavelengths were 202 and 320 nm, respectively. The accuracy and precision of the assay, expressed as the percentage deviation of measured values from true values and the percentage coefficient of variation, respectively, were ≤ 10% at all concentrations except for the percentage coefficient of variation at the lower limit of quantitation (5 ng/ml). The assay has been successfully used for the analysis of plasma samples from a pharmacokinetic study in human volunteers.
Prediction of workpiece deformation in a fixture system using the finite element method

Abstract Knowledge of workpiece deformations induced by loading in a fixture–workpiece system is important to ensure quality part production. Suitable methods for accurately predicting such deformations are essential to the design and operation of fixtures. In this regard, finite element modeling has been widely applied by researchers and practitioners. However, these studies generally neglect the role of compliance of the fixture body on workpiece deformation. Also lacking is knowledge of the effects of different finite element model parameters on workpiece deformation. This study uses finite element analysis (FEA) to model a fixture–workpiece system and to explore the influence of compliance of the fixture body on workpiece deformation. In addition, the effects of certain finite element model parameters on the prediction accuracy are also examined. Experimental verification of the workpiece deformations and locator reaction forces predicted by the FEA model shows agreement within 5% of the experimental data. For the fixture–workpiece system analyzed in this study, it was found that 98% of all system compliance is captured by modeling just the workpiece and fixture contact tips. The remainder of deformation occurred in the other fixture components. The accuracy and computational time tradeoffs are given for various fixture models.
Etigy and screening of cervical cancer

Abstract The etiology of cervical carcinoma is intrinsically linked to multiple interactions of viral products, particularly from human papillomavirus, with cellular DNA over time. Additional destabilization and interaction with circulating nicotine metabolites and with human-immunodeficiency-virus effects further increase the likelihood of a sustained neoplastic process. Protection of patients from the development of cervical carcinoma includes recommendations to not smoke and to avoid exposure to sexually transmitted diseases. Screening for the presence of a neoplastic process will decrease the incidence of the disease, but barriers to successful screening must be addressed and appropriate intervals for screening must be clinically driven. Recognition that infection with human immunodeficiency virus changes the time course of the neoplastic process is essential to the screening process.
Making generic functions useable in Smalltalk

There have traditionally been two approaches to object orientation with respect to defining code to operate on objects. The first and more common one is message passing. The other is generic functions which use multiple dispatch (also known as multimethods). While Smalltalk provides one of the simplest implementations of a message passing system, there are some circumstances where generic functions provide a more concise solution to the problem. The goals of this project are two-fold: first, to take a look at how to implement generic functions in Smalltalk alongside the existing message passing system, and secondly, to look into how to nicely integrate the infrastructure for creating generic functions into the Squeak programming environment.
Theoretical Analysis of Wankel Engine Combustion

Abstract A one-dimensional model for. the spark ignition Wankel engine combustion is presented, The model is based on the use of a turbulent diffusivity for heat and mass transfer by which the motion of the finite-thickness, unsteady turbulent flame is calculated. A one-step second order reaction rate equation is used and wall heat transfer losses are included. The instantaneous chamber pressure and the local and instantaneous gas temperature, density, and velocity are calculated. Results are presented for a typical engine design. Initial results of two parametric studies are also reported, but their generalization is not undertaken, at this point, due to the complexity of the process.
Using a Metaphor Exercise to Explore the Principles of Organizational Culture

Students often complain that text discussions of culture are bland, lack practical application, and do not provide them with tools to assess the cultural dynamics of the groups in which they work. This article presents an exercise that the authors developed to show their students how they can assess and better understand Bion's principles of culture. It shows how to administer the exercise and how it can offer feedback regarding the culture of their class or the class groups in which they participate.
Trans-isomerization of oleic acid and potassium oleate by ionizing radiation

The oleic acid of IV 89.2 was irradiated with cathode rays at doses of 15 × 106 to 70 × 106 rep and was found to have beentrans-isomerized from 2.5% at 45 × 106 rep to 9.4% at 70 × 106 rep; the oleic acid of IV 89.8 irradiated at doses of 13.4 × 106 to 401.6 × 106 rep and was found to have beentrans-isomerized to 4.9% at 187.4 × 106 rep and to 14.6% at 401.6%. Thetrans-isomerization was independent of oxygen. Aqueous solutions of potassium oleate at 1% concentration were irradiated with doses from 1 × 106 rep to 5 × 106 rep. The oleic acid recovered from the irradiated solutions was found to have beentrans-isomerized from 8.1% at 1 × 106 rep to 1.9% at 5 × 106 rep; the oleic acid recovered from the 2.5% solutions was found to have beentrans-isomerized to 8.3% at 5 × 106 rep, 11.9% at 10 × 106 rep, and 0.1% at 30 × 106 rep. A modified “baseline” technique in infrared spectrophotometric analysis is described.
Compound synapses within the GABAergic innervation of the auditory inner hair cells in the adolescent mouse

Ultrastructural investigation of the gamma-aminobutyric acid (GABA) component of the inner spiral bundle in adolescent mice revealed a pathway of glutamic acid decarboxylase (GAD)-positive and -negative fibers and vesiculated endings that contact inner hair cells and their afferents through a complex of axosomatic and axodendritic synapses. Ultrastructural details were investigated by using conventional electron microscopy. Several synaptic arrangements were observed: Main axosomatic synapses form between vesiculated endings and individual or adjoining inner hair cells (interreceptor synapses). Spinous synapses form on long, spinelike processes that protrude from inner hair cells to reach distant efferent endings. The efferent endings associate with inner hair cells and their synaptic afferents through compound synapses-serial, "converging," and triadic-otherwise characteristic of sensory relay nuclei. Serial synapses form by the sequential presynaptic alignment of the efferent-->receptor-->afferent components. Converging synapses result from the simultaneous apposition of a receptor ribbon synapse and a presynaptic efferent terminal on a recipient afferent dendrite. Triadic synapses comprise a vesiculated efferent ending in contact with an inner hair cell and with its synaptic afferent. Additionally, efferent endings may form simple axodendritic and axoaxonal synapses with GAD-negative vesiculated endings. The combination of different synaptic arrangements leads to short chains of compound synapses. It is assumed that these synaptic patterns seen in the adolescent mouse represent adult synaptology. The patterns of synaptic connectivity suggest an integrative role for the GABA/GAD lateral efferent system, and imply its involvement in the pre- and postsynaptic modulation of auditory signals.
Improved stability of amorphous zinc tin oxide thin film transistors using molecular passivation

The role of back channel surface chemistry on amorphous zinc tin oxide (ZTO) bottom gate thin film transistors (TFTs) has been characterized by positive bias-stress measurements and x-ray photoelectron spectroscopy. Positive bias-stress turn-on voltage shifts for ZTO-TFTs were significantly reduced by passivation of back channel surfaces with self-assembled monolayers of n-hexylphosphonic acid when compared to ZTO-TFTs with no passivation. These results indicate that adsorption of molecular species on the exposed back channel of ZTO-TFTs strongly influence observed turn-on voltage shifts, as opposed to charge injection into the dielectric or trapping due to oxygen vacancies.
Modern geochemical and molecular tools for monitoring in-situ biodegradation of MTBE and TBA

Methyl tert-butyl ether (MTBE) is a major gasoline oxygenate worldwide and a widespread groundwater contaminant. Natural attenuation of MTBE is of practical interest as a cost effective and non-invasive approach to remediation of contaminated sites. The effectiveness of MTBE attenuation can be difficult to demonstrate without verification of the occurrence of in-situ biodegradation. The aim of this paper is to discuss the recent progress in assessing in-situ biodegradation. In particular, compound-specific isotope analysis (CSIA), molecular techniques based on nucleic acids analysis and in-situ application of stable isotope labels will be discussed. Additionally, attenuation of tert-butyl alcohol (TBA) is of particular interest, as this compound tends to occur alongside MTBE introduced from the gasoline or produced by (mainly anaerobic) biodegradation of MTBE.
23 STATURAL GROWTH AND SKELETAL MATURATION IN CHILDREN WITH CONGENITAL ADRENAL HYPERPLASIA (CAH)

23 STATURAL GROWTH AND SKELETAL MATURATION IN CHILDREN WITH CONGENITAL ADRENAL HYPERPLASIA (CAH)
Language: Creating a Literate Environment for Reading and Writing Development

This paper provides speech-language pathologists with information they can use to assist general and special education teachers of kindergarten and primary level students in creating a literate environment for reading and writing instruction. Included is a discussion of those aspects of the preschooler's rich literate environment which promote reading and writing development and specific suggestions for teacher modeling for organizing and managing the classroom, and for providing a range of meaningful reading and writing opportunities. Instruction which incorporates these suggestions is intended to extend and refine children's written language skills acquired prior to school and to provide a transition from the informal instruction offered in the home environment to the formal instruction found in the schools.
The Peak Boiling Heat Flux in Saturated Ethanol-Water Mixtures

The present work provides original measurements of the burnout heat flux in saturated ethanol-water mixtures, over the full range of concentrations. These data were obtained at atmospheric pressure on horizontal cylinders, ranging from 0.51 to 2.16 mm in diameter. They reveal significant improvements of the peak heat flux for mixtures, over that which would be expected from pure fluids with the properties of the mixture. This improvement is most pronounced at low ethanol mass fractions. McEligot has suggested that the improved heat flux results from a subcooling created by selective distillation at the liquid-vapor interface. Combining this idea with a recent correlation of subcooled burnout, we estimate the extent of effective subcooling qualitatively and discuss the use of this estimate to correlate burnout in binary mixtures. Two dimensionless groups are proposed to characterize this effec­ tive subcooling, both based on appropriate characterizations of the phase equilibrium diagram.
Biochemical systems theory: operational differences among variant representations and their significance.

An appropriate language or formalism for the analysis of complex biochemical systems has been sought for several decades. The necessity for such a formalism results from the large number of interacting components in biochemical systems and the complex non-linear character of these interactions. The Power-Law Formalism, an example of such a language, underlies several recent attempts to develop an understanding of integrated biochemical systems. It is the simplest representation of integrated biochemical systems that has been shown to be consistent with well-known growth laws and allometric relationships—the most regular, quantitative features that have been observed among the systemic variables of complex biochemical systems. The Power-Law Formalism provides the basis for Biochemical Systems Theory, which includes several different strategies of representation. Among these, the synergistic-system (S-system) representation is the most useful, as judged by a variety of objective criteria. This paper first describes the predominant features of the S-system representation. It then presents detailed comparisons between the S-system representation and other variants within Biochemical Systems Theory. These comparisons are made on the basis of objective criteria that characterize the efficiency, power, clarity and scope of each representation. Two of the variants within Biochemical Systems Theory are intimately, related to other approaches for analyzing biochemical systems, namely Metabolic Control Theory and Flux-Oriented Theory. It is hoped that the comparisons presented here will result in a deeper understanding of the relationships among these variants. Finally, some recent developments are described that demonstrate the potential for further growth of Biochemical Systems Theory and the underlying Power-Law Formalism on which it is based.
Gas-phase reactions of divalent Ni complex ions with acetonitrile: Chelate ring size, inductive, and steric effects

Ni(II) complexes of a series of pentadentate polyamine ligands have been reacted with CH3CN in the gas phase using a modified quadrupole ion trap mass spectrometer. The ligands have structural features such that upon complexation, chelate ring size, sterics, and inductive effects can be evaluated in the gas phase. Rate and equilibrium constants for CH3CN addition to the metal complexes show that there is a general decrease in the gas-phase reactivity as the chelate ring size is increased. Density functional theory calculations at the B3LYP/LANL2DZ level of theory have been used to obtain minimum energy structures and Mulliken charges for the complexes. The decreased reactivity observed as the chelate ring size is increased correlates with a decrease in the atomic charge on the metal. A larger chelate ring size enhances ligand flexibility and improves the overlap of the ligand’s donor atoms with the metal center. Adding methyl groups adjacent to or on the nitrogen donor groups of a ligand also decreases the rate and equilibrium constants for the reactions of a given complex with CH3CN. Analysis of Mulliken charges for these complexes indicates that both inductive and steric effects are responsible for lower complex reactivity. These results suggest that while the gas-phase reactivity of a metal complex with CH3CN is very dependent on the functional groups directly bound to the metal, in some cases steric effects can conceal the correlation between reactivity and coordination structure.
Primate auditory recognition memory performance varies with sound type

Neural correlates of auditory processing, including for species-specific vocalizations that convey biological and ethological significance (e.g., social status, kinship, environment), have been identified in a wide variety of areas including the temporal and frontal cortices. However, few studies elucidate how non-human primates interact with these vocalization signals when they are challenged by tasks requiring auditory discrimination, recognition and/or memory. The present study employs a delayed matching-to-sample task with auditory stimuli to examine auditory memory performance of rhesus macaques (Macaca mulatta), wherein two sounds are determined to be the same or different. Rhesus macaques seem to have relatively poor short-term memory with auditory stimuli, and we examine if particular sound types are more favorable for memory performance. Experiment 1 suggests memory performance with vocalization sound types (particularly monkey), are significantly better than when using non-vocalization sound types, and male monkeys outperform female monkeys overall. Experiment 2, controlling for number of sound exemplars and presentation pairings across types, replicates Experiment 1, demonstrating better performance or decreased response latencies, depending on trial type, to species-specific monkey vocalizations. The findings cannot be explained by acoustic differences between monkey vocalizations and the other sound types, suggesting the biological, and/or ethological meaning of these sounds are more effective for auditory memory.
Effectiveness of computer-based education in colleges

AbstractA meta-analysis of findings from 101 controlled evaluations showed that computer-based education (CBE) has usually had positive effects on college students. CBE raised student examination scores by 0.26 standard deviations in the average study—a small but significant effect. CBE effects were somewhat lower in unpublished studies than they were in published ones, and they were also somewhat lower in the hard and nonlife sciences than in the social sciences and education. In addition, CBE produced small but positive changes in student attitudes toward instruction and computers. Finally, CBE also reduced substantially the amount of time needed for instruction.
Anterior cingulate cortex choline levels in female adolescents with unipolar versus bipolar depression: a potential new tool for diagnosis.

Background Delayed diagnosis in bipolar disorder (BD) due to misdiagnosis as major depressive disorder (MDD) is a significant public health concern. Thus, identification of relevant diagnostic biomarkers is a critical unmet need, particularly early in the course of illness. The anterior cingulate cortex (ACC) is thought to play an important role in mood disorder pathophysiology. Case-control studies utilizing proton-1 magnetic resonance spectroscopy (1H-MRS) have found increased total choline levels in several brain regions in MDD. However, there are no published 1H-MRS reports directly comparing adolescents with MDD and BD. We hypothesized that ACC choline levels would be increased in adolescents with unipolar versus bipolar depression.
Nonlint material identification using computer vision and pattern recognition

ABSTRACT This paper discusses methods used to evaluate a feature space for identification of non-lint mate-rial (trash) in cotton samples. A main criterion for accepting any feature in the identification task was invariance under translation, rotation, and, in most cases, scale. In subsequent processing, most features were normalized. Classical grouping was performed in an n-dimensional featurespace using divisive hierarchical clustering based on the Euclidian distance metric. The best re-sults for identifying bark, stick, and leaf/pepper trash in the sample data set was 92%. By cate-gory, bark was identified correctly 88%, stick 84%, and leaf/pepper 94% of the time. Identifica- tion between leaf and pepper could be handled by defining an area cutoff in the pepper-leaf continuum. 2. BACKGROUND The Southwestern Cotton Ginning Research Laboratory (SWCGRL) is part of the United StatesDepartment of Agriculture (USDA), Agricultural Research Service. SWCGRL is charged withinvestigating any aspects of cotton ginning where improvement could result in better return for the
Privacy concerns in e-commerce: an empirical investigation of gender differences

Privacy of personal information disclosed during e-commerce transactions continues to be an important issue for internet users. Previous research indicates the existence of gender differences in privacy concerns online. However, little has been done to explore these differences in the context of various dimensions of privacy and their influence on purchasing behaviour. This study focuses on gender differences from two perspectives. First, it explores gender differences along three specific dimensions of privacy. Second, it considers the moderating role of gender in the relationships between dimensions of privacy and purchasing behaviour. Results of this study show that female and male internet users do not differ in their concern about information privacy online. However, they differ in the way privacy concerns influence their purchasing behaviour online.
Do plant defenses enhance or diminish prey suppression by omnivorous Heteroptera

Abstract Omnivorous plant-feeding predators have been predicted to both increase and decrease prey consumption on resistant host-plants because of behavioral shifts in food preferences and direct ingestion of phytotoxins, respectively. To help resolve this debate, we reviewed the published literature on plant defense-heteropteran interactions using both vote-counting and meta-analytical approaches. The Heteroptera are ideal for this analysis because as a group they are broadly omnivorous, critical in the biocontrol of crop pests, and frequently come in contact with plants varying in quality. We identified 37 studies that matched our search criteria, involving at least 16 species of Heteroptera. Overall, plant resistance lowered the abundance of heteropterans in the field, but had virtually no impact on their performance when reared in the lab (aside from a significant, albeit minor, increase in development time). Prey consumption was strongly affected by plant resistance; however, the outcome was extremely variable with near equal evidence for increasing (22 cases) vs. decreasing (21 cases) predation on resistant host-plants. Thus, prey consumption is far more variable across plant-types differing in quality when compared with either abundance or performance. Heteropteran family and developmental stage (adult vs. nymph) were poor predictors of the outcome for prey suppression. Our results indicate that the feeding ecology of omnivorous heteropterans is highly contingent on plant defense expression, more so than other ecologically-relevant traits, but the factors mediating behavioral shifts in prey consumption remain elusive.
Air-water hybrid cooling for computer servers: A case study for optimum cooling energy allocation

Air-water hybrid cooling offers flexible design choices for computer systems with components of different thermal management needs. On one hand, water cooling enables the continuous growth of CPU performance and increasing packaging density. High performance cold plates such as microchannels have been successfully implemented for water cooling in previous high-end systems. When coupled with an air-water heat exchanger or radiator, the water loop becomes a closed one with no need for facility chilled water. This significantly reduces the complexity to deploy the server in the data center. On the other hand, for components with less thermal demand, traditional air-cooling technology is adequate with low cost, high availability and better serviceability. For the computer system as a whole, an air-water hybrid cooling system may be optimized. Such a hybrid system typically requires pumps to drive the water loops, air-movers to drive air through the radiator and blowers or fans to drive the air flow for component cooling. It is the focus of this paper to study the optimum allocation of energy between the pumps and air-movers for a given total cooling energy budget and overall load. The goals are to achieve better overall thermal performance and to reduce the cooling energy consumption. To this end models for each cooling block are established based on test data. These include the air-water heat exchanger, pumps, blowers, and cold plates. These models are linked together to predict the overall thermal system operating points for different application scenarios. A parametric study is then conducted to define the near optimum allocation of cooling energy for these scenarios that meets the thermal design objectives. Additionally, sub-threshold leakage for the CPU is taken into account to enhance the model since temperature provides positive feedback. It is shown through modeling that additional performance enhancement is possible with judicious allocation of cooling energy for a given overall energy budget. It is argued in this paper that overall energy efficiency can be improved significantly through intelligent data driven energy allocation.
Dry etching of bulk single-crystal ZnO in CH 4 /H 2 -based plasma chemistries

Abstract The effect of inert gas additive (He, Ar, Xe) to CH4/H2 discharges for dry etching of single crystal ZnO was examined. The etch rates were higher with Ar or Xe addition, compared to He but in all cases the CH4/H2-based mixtures showed little or no enhancement over pure physical sputtering under the same conditions. The etched surface morphologies were smooth, independent of the inert gas additive species and the Zn/O ratio in the near-surface region decreases as the mass number of the additive species increases, suggesting preferential sputtering of O. The plasma etching improved the band-edge photoluminescence intensity from the ZnO for the range of ion energies used here (290–355 eV), due possibly to removal of surface contamination layer.
Amino-acid Protection of Ultra-violet-irradiated Bacillus subtilis

IT has been reported1 that cultivation of Hansenula wingei, prior to ultra-violet irradiation, in beef-extract glucose broth supplemented with small concentrations of either tryptophan, cystine, tyrosine, phenylalanine, leucine, cysteine, threonine, isoleucine, histidine, or the amino-acid analogues, ethionine or norvaline, protected this yeast against ultra-violet exposure. The hypothesis was made that amino-acids may be strongly active as protective or reactivating agents in Gram-positive organisms, but only slightly active in this capacity in Gram-negative organisms because of permeability differences in the two types of organisms. The present investigation was initiated to determine if amino-acids reverse or protect against the inactivating effects of ultra-violet radiation in a Gram-positive bacterium.
Modelling fluid flow in domains containing moving interfaces

A method for the numerical simulations of fluid flow in domains containing moving rigid objects or boundaries is presented, which falls into the general category of arbitrary Lagrangian-Eulerian methods. The method is based on a fixed mesh that is modified locally both in space and time to describe the moving interfaces that are allowed to displace independently of the mesh. It results in a fully robust formulation capable of calculating in irregular meshes on domains of complex geometry containing moving devises without danger of the mesh becoming unsuitable due to its continuous deformation. This work presents the ideas in the context of two space dimensions, and constitutes the first stage in the development of a three-dimensional model to interface with the KIVA simulator developed by Los Alamos National Laboratory. The method’s capabilities and accuracy are assessed using several examples including a case that has an analytical solution.
Diurnal and seasonal variations in intraocular pressure in the rabbit

The diurnal variations in intraocular pressure in the rabbit were measured during a period of 12 months in a cross-sectional study. The average intraocular pressure of all the measurements taken during the year was 19.6 +/- 2.0 mmHg (mean +/- S.D.; n = 1957). The daily curve showed a continuous rise during the day from 18.2 +/- 1.7 mmHg (n = 175) at 0800 hr to 20.6 +/- 1.8 mmHg (n = 167) at 1700 hr. During the month of June, when the measurements were extended until midnight, this rise in intraocular pressure continued until 2200 hr, reached a level of 22.5 +/- 1.6 (n = 16), and started to decline. A similar daily pattern was observed throughout the year. The annual curve showed two peaks, during the summer and winter seasons, with a daily average of 20.2 +/- 2.1 (n = 404) and 20.2 +/- 2.0 (n = 638) respectively. The lowest average daily IOP value was obtained during the spring and was 18.8 +/- 2.0 (n = 509). An intermediate level between the summer/winter and the spring values was obtained during the autumn and was 19.4 +/- 1.7 (n = 406).
Autoimmunity to the thyroid stimulating hormone receptor

Summary Thyroid disorders are the most common endocrine diseases and affect a large segment of the population. Most of the thyroid diseases are autoimmune in nature and can be broadly grouped into two categories; one mediated by autoimmune responses to the thyroglobulin (i.e. Hashimoto's thyroiditis), and the other mediated by autoimmunity to the thyrotropin receptor (primarily Graves' disease). Although patients with autoimmune thyroid diseases exhibit immune responses against a number of thyroid antigens, such as thyroglobulin, thyrotropin receptor and thyroid peroxidase, responses directed against a specific antigen appear to play an important role in the disease pathogenesis. For example, Hashimoto's thyroiditis is primarily mediated by T cell responses directed toward the thyroglobulin receptor, whereas Graves' disease is mediated by antibodies directed against the thyrotropin receptor. In this review we will focus on thyroid diseases mediated by autoimmune responses tothethyrotropinreceptor.
Cell cycle control and cancer

Multiple genetic changes occur during the evolution of normal cells into cancer cells. This evolution is facilitated in cancer cells by loss of fidelity in the processes that replicate, repair, and segregate the genome. Recent advances in our understanding of the cell cycle reveal how fidelity is normally achieved by the coordinated activity of cyclin-dependent kinases, checkpoint controls, and repair pathways and how this fidelity can be abrogated by specific genetic changes. These insights suggest molecular mechanisms for cellular transformation and may help to identify potential targets for improved cancer therapies.
Biochemical Evaluation of the Decarboxylation and Decarboxylation-Deamination Activities of Plant Aromatic Amino Acid Decarboxylases

Plant aromatic amino acid decarboxylase (AAAD) enzymes are capable of catalyzing either decarboxylation or decarboxylation-deamination on various combinations of aromatic amino acid substrates. These two different activities result in the production of arylalkylamines and the formation of aromatic acetaldehydes, respectively. Variations in product formation enable individual enzymes to play different physiological functions. Despite these catalytic variations, arylalkylamine and aldehyde synthesizing AAADs are indistinguishable without protein expression and characterization. In this study, extensive biochemical characterization of plant AAADs was performed to identify residues responsible for differentiating decarboxylation AAADs from aldehyde synthase AAADs. Results demonstrated that a tyrosine residue located on a catalytic loop proximal to the active site of plant AAADs is primarily responsible for dictating typical decarboxylase activity, whereas a phenylalanine at the same position is primarily liable for aldehyde synthase activity. Mutagenesis of the active site phenylalanine to tyrosine in Arabidopsis thaliana and Petroselinum crispum aromatic acetaldehyde synthases primarily converts the enzymes activity from decarboxylation-deamination to decarboxylation. The mutation of the active site tyrosine to phenylalanine in the Catharanthus roseus and Papaver somniferum aromatic amino acid decarboxylases changes the enzymes decarboxylation activity to a primarily decarboxylation-deamination activity. Generation of these mutant enzymes enables the production of unusual AAAD enzyme products including indole-3-acetaldehyde, 4-hydroxyphenylacetaldehyde, and phenylethylamine. Our data indicates that the tyrosine and phenylalanine in the catalytic loop region could serve as a signature residue to reliably distinguish plant arylalkylamine and aldehyde synthesizing AAADs. Additionally, the resulting data enables further insights into the mechanistic roles of active site residues.
Kidney retransplants after initial graft loss to vascular thrombosis

Background: Vascular thrombosis early after a kidney transplant is an infrequent but devastating complication. Often, no cause is found. These recipients are generally felt to be good candidates for a retransplant. However, their ideal care at the time of the retransplant and their outcomes have not been well documented. We studied outcomes in 16 retransplant recipients who had lost their first graft early posttransplant ( < 1 month) to vascular thrombosis. Methods: Of 2003 kidney transplants between 1 January 1984 and 30 September 1998, we identified 32 recipients who had lost their first graft early posttransplant to vascular thrombosis. Of these 32 recipients, 16 were subsequently retransplanted and detailed chart reviews were done. Results: Of the 16 retransplant recipients, 12 lost their first graft to renal vein thrombosis and 4 to renal artery thrombosis. Thrombosis generally occurred early (mean, 3.6 d). Five recipients underwent a complete hematologic workup to rule out a thrombophilic disorder before their retransplant: 4 had a positive result (presence of antiphospholipid antibodies, n = 3; increased homocysteine levels, n = 1). These 4 recipients, along with 1 other recipient who had a strong family history of thrombosis, underwent thrombosis prophylaxis at the time of their retransplant. Prophylaxis consisted of low-dose heparin for the first 3-5 d posttransplant, followed by acetylsalicylic acid or Coumadin. Of the 16 retransplant recipients, none developed thrombosis. Of the 5 who underwent thrombosis prophylaxis, none had significant bleeding complications. At a mean follow-up of 5.4 yr, 10 (63%) recipients have functioning grafts. Causes of graft loss in the remaining 6 recipients were death with function (n = 5, 31%) and acute rejection (n = 1, 6%). Graft and patient survival rates after these 16 retransplants were equivalent to results after primary transplants. The incidence of acute and chronic rejection was also no different (p = ns). Conclusion: Vascular thrombosis in the absence of obvious technical factors should prompt a workup for a thrombophilic disorder before a retransplant. Recipients with an identified disorder should undergo prophylaxis at the time of the retransplant. Results in these retransplant recipients are equivalent to those seen in primary transplant recipients.
Measurements and Monte Carlo simulation of grain growth in the heat-affected zone of Ti–6Al–4V welds

Abstract Grain size and topological class distributions in the heat-affected zone (HAZ) of gas tungsten arc welded Ti–6Al–4V alloy were measured for various heat inputs in the range of 0.55–4.33 MJ m −1 . The evolution of grain structure and topological class distributions were also calculated using a three-dimensional Monte Carlo model utilizing thermal cycles computed from a well tested numerical heat transfer and fluid flow model. Both the experimental data and the calculated results showed that the average prior-β grain size near the fusion plane was about four to twelve times larger than the average grain size in the base plate, depending on the heat input. At locations equidistant from the fusion plane, the grains were larger in the mid-section vertical symmetry plane as compared to those at the top surface due to local variations of the thermal cycles. The normalized grain size distributions were unaffected by the local differences in the thermal cycles. It is demonstrated that the presence of a spatial gradient of temperature in the HAZ significantly impeded grain growth due to thermal pinning effect. Furthermore, the steep temperature gradients near the fusion plane did not introduce any significant texture in the grains. Both the experimental data and the calculated results indicated that the grains in the HAZ of the Ti–6Al–4V alloy were significantly smaller than the grains in the commercially pure titanium for identical welding conditions.
Modeling the interferometric radius measurement using Gaussian beam propagation

We model the interferometric radius measurement using Gaussian beam propagation to identify biases in the measurement due to using a simple geometric ray-trace model instead of the more complex Gaussian model. The radius measurement is based on using an interferometer to identify the test part's position when it is at two null locations, and the distance between the positions is an estimate of the part's radius. The null condition is observed when there is no difference in curvature between the reflected reference and the test wavefronts, and a Gaussian model will provide a first-order estimate of curvature changes due to wave propagation and therefore changes to the radius measurement. We show that the geometric ray assumption leads to radius biases (errors) that are a strong function of the test part radius and increase as the radius of the part decreases. We tested for a bias for both microscaled (<1 mm) and macroscaled parts. The bias is of the order of parts in 10(5) for micro-optics with radii a small fraction of a millimeter and much smaller for macroscaled optics. The amount of bias depends on the interferometer configuration (numerical aperture, etc.), the nominal radius of the test part, and the distances in the interferometer.
Photoconductive gain of SiGe/Si quantum well photodetectors

Abstract A SiGe/Si Multiple Quantum Wells (MQWs) structure is proposed for highly sensitive photodetection. A large photoconductive gain is obtained because of the unique SiGe/Si band structure, i.e., a large band offset in the valence band, but a small band offset in the conduction band. Such a structure allows the trapping of photogenerated holes inside the valance band quantum wells. Alternatively, photogenerated electrons appear in shallow quantum wells and have relatively high mobility. These give rise to a large photoconductive gain. The calculated photoconductive gain for this structure exceeds 2 × 107. Experimental results confirmed a high gain of the structure.
Anatomy of Ambivalence: The International Community and Human Rights Abuse in the North Caucasus

Why has the international community done so little to address grave human rights abuses in Chechnya and the North Caucasus?
The Mre11 Complex and the Response to Dysfunctional Telomeres

In this study, we examine the telomeric functions of the mammalian Mre11 complex by using hypomorphic Mre11 and Nbs1 mutants (Mre11(ATLD1/ATLD1) and Nbs1(Delta)(B/)(DeltaB), respectively). No telomere shortening was observed in Mre11(ATLD1/ATLD1) cells after extensive passage through culture, and the rate of telomere shortening in telomerase-deficient (Tert(Delta)(/)(Delta)) Mre11(ATLD1/ATLD1) cells was the same as that in Tert(Delta)(/)(Delta) alone. Although telomeres from late-passage Mre11(ATLD1/ATLD1) Tert(Delta)(/)(Delta) cells were as short as those from Tert(Delta)(/)(Delta), the incidence of telomere fusions was reduced. This effect on fusions was also evident upon acute telomere dysfunction in Mre11(ATLD1/ATLD1) and Nbs1(Delta)(B/)(DeltaB) cells rendered Trf2 deficient by cre-mediated TRF2 inactivation than in wild-type cells. The residual fusions formed in Mre11 complex mutant cells exhibited a strong tendency toward chromatid fusions, with an almost complete bias for fusion of telomeres replicated by the leading strand. Finally, the response to acute telomere dysfunction was strongly impaired by Mre11 complex hypomorphism, as the formation of telomere dysfunction-induced DNA damage foci was reduced in both cre-infected Mre11(ATLD1/ATLD1) Trf2(F/)(Delta) and Nbs1(Delta)(B/)(DeltaB) Trf2(F/F) cells. These data indicate that the Mre11 complex influences the cellular response to telomere dysfunction, reminiscent of its influence on the response to interstitial DNA breaks, and suggest that it may promote telomeric DNA end processing during DNA replication.
Radiobiological studies with cyclotron-produced neutrons currently used for radiotherapy.

Abstract The introduction of high energy cyclotron-produced neutrons into radiotherapy is an exciting development, and their radiobiological properties need to be studied in detail. Survival curves have been determined for single and split doses of 60 Co gamma rays and also for neutrons generated at the Naval Research Laboratory cyclotron (35 Mev d→Be). The split dose experiments indicate that the accumulation and repair of sublethal damage is virtually absent for neutrons, while being of great importance for gamma rays. Comparative measurements have been made with three high energy cyclotron produced neutron beams: TAMVEC (50 Mev d→Be), the Naval Research Laboratory (35 Mev d→Be), and a beam designed to simulate that used at the Hammersmith Hospital (16 Mev d→Be). The oxygen enhancement ratio remains unchanged at about 1.6 for all three neutron spectra, but the relative biological effectiveness changes significantly with neutron energy and this must be taken into account when comparing treatment regimens at the various neutron therapy centers.