cssi/SciSciGPT-SciSciNet huggingface dataset:
Insertion of a left ventricular assist device in patients without thorough transplant evaluations: a worthwhile risk?

Abstract Objectives Patients in acute cardiogenic shock may require placement of left ventricular assist devices before undergoing standard pretransplant evaluations. This practice raises ethical and logistic concerns and has led us to investigate the short- and long-term outcomes for this patient population. Methods and results We examined our adult bridge-to-transplant left ventricular assist device population over a 6-year period to characterize those patients with acute cardiogenic shock who received left ventricular assist devices on an emergency basis (ie, placement of a device within 24 hours of being listed for cardiac transplantation). Outcomes before and after transplant were compared with those of candidates with nonemergency evaluations by Kaplan-Meier survival curves and the Fisher exact test where appropriate. Of the 115 patients who required left ventricular assist device support, 73 (63%) patients required emergency placement; 70% of these patients survived to transplant compared with 83% of those with nonurgent device implantation (not statistically significant). Posttransplant survival curves were similar for patients with emergency device placement and those with nonurgent placement (not statistically significant). Twenty-two patients having emergency device placement did not undergo heart transplantation because of multisystem organ failure (14), device support withdrawal from irreversible neurologic injury (4), device or technical problems (2), and left ventricular assist device explant due to myocardial recovery (2). Conclusions At our institution, the majority of left ventricular assist devices are placed on an emergency basis. Few of these patients require discontinuation of device support due to undetected conditions during abbreviated preoperative evaluation. Survival before and after transplant is comparable with those of patients who undergo nonurgent left ventricular assist device placement or medical therapy.
Identification of Calcium Hydrogen Phosphate Dihydrate Crystals in Human Fibrocartilage

RECENTLY, we identified microcrystalline calcium pyro-phosphate dihydrate in certain pathological human synovial fluids1. Roentgenograms of the involved joints showed calcifications in cartilaginous structures; the clinical picture was distinctive enough to suggest a specific syndrome, which we named ‘pseudogout’2. In two cases multiple cartilages were examined post mortem and most contained localized deposits of these crystals3. The interplanar spacings found on X-ray diffraction powder pattern are virtually identical with those reported for calcium pyrophosphate dihydrate prepared by Brown et al.4 by hydrolytic degradation of calcium polymetaphosphate gel. Monoclinic and triclinic dimorphs have been identified by these same workers5. In human material, the triclinic dimorph predominates although interplanar spacings indicative of the monoclinic form are detected frequently6.
Business networks, “brain circulation”, and the American Chinese diaspora

Purpose – Overseas Chinese business networks have had a profound effect on the economic development of mainland China and on the global economy as a whole. Such networks are based predominantly on familial, language and cultural factors and provide a foundation on which business is conducted, often with reduced transaction costs and with resilience to major shifts in the financial markets. This paper aims to explore business networks in the US Chinese diaspora.Design/methodology/approach – The paper begins with a brief introduction to the concept of ethnic business networks. Subsequent sections provide historical background on the Chinese diaspora and the role Chinese business networks have played around the world. An examination of how such networks have evolved in the US context follows. Finally, implications are discussed and a research agenda is suggested.Findings – It is suggested that a different type of business networking pattern has evolved in the US context, one that is less reliant on the tradi...
Rapid turnover of sphingosine synthesized de novo from [14C]serine by Chinese hamster ovary cells.

Summary It has been hypothesized that complex sphingolipids may serve as another “lipid second messenger” system via their hydrolysis to free sphingosine, which inhibits protein kinase C and affects multiple cellular functions. To investigate sphingolipid turnover, Chinese hamster ovary cells were pulse labelled with [ 14 C]serine and the [ 14 C]sphingosine in cellular sphingolipids was determined over time. Much of the radiolabelled sphingosine was initially seen in ceramides and was incorporated into sphingomyelin during the 5-hour chase. A major portion of the radiolabel that was initially seen in other sphingolipids disappeared over time. Overall, about half of the total long-chain bases made during this pulse were degraded within 2 to 5 h, depending on the method of analysis. Hence, a substantial portion of the sphingosine synthesized de novo by these cells is turned over fairly quickly. Since the doubling time of these cells is 12 h, this rapid turnover may reflect the remodelling of the cell surface, or the utilization of the free sphingosine derived from sphingolipid turnover, as part of the control of cell growth and division.
On the resilience of bicultural exchange under prolonged and persistent acculturative stress: implications for the study of demoralization

Drawing on the historical experiences of a bicultural society in Goa, a former Portuguese state on the western coast of India, this article describes how the exchange between two groups with conflicting and contrasting cultures, Hindus and Christians, continued to persist and grow for more than four centuries. The Goan acculturation took place in three stages. A relatively peaceful co-existence of the two groups, lasting about 30 years, was followed by almost 200 years of both Christianization and ‘westernization’ as well attempts to eliminate the interaction between Hindus and Christians. These attempts were unsuccessful and eventually the discriminatory practices were outlawed. A skillful collective use of adaptive strategies led to the prevention and minimization of demoralization and the creation of a vibrant hybrid culture, the Indo-Portuguese culture of Goa.
Pulsed laser deposited La2−xSrxCuO4+δ thin films

Abstract High quality La2−xSrxCuO4+δ thin films have been grown with different strain and oxygen content. Strain was controlled by depositing either compressive or tensile SrLaAlO4 buffer layer on SrTiO3 substrate. Oxygen content was controlled by whether or not using an ozone/molecular oxygen mixture during cooling to achieve better oxygen uptake. We found that both full oxygenation and compressive in-plane strain are critical for the superconducting properties of the La2−xSrxCuO4+δ thin films, and perhaps the compressive strain makes the oxygenation much easier.
A self-consistent fragmented-flux-tube calculation of the low-mass hadron spectrum

Abstract An approximate self-consistent approach to the calculation of the low-mass hadron ( q q , qqq ,…, GG ,…) spectrum is presented, in which the fragmentation of the flux tube joining the valence quarks and gluons is taken into account. Ground-state 0++ and 2++ GG gluonium masses of 1.34 and 1.73 GeV are predicted.
Effect of intravenous heroin and naloxone on regional cerebral blood flow in the conscious rat

Abstract Regional cerebral blood flow (RCBF) was measured with the [ 14 C]iodoantipyrine technique and quantitative autoradiography in awake, restrained rats shortly after intravenous injection of heroin, naloxone or naloxone before heroin. The RCBF observed in these animals was compared to those obtained in similarly treated, saline-injected rats. In an identically treated series of animals, no significant change in arterial blood gases, pH or bicarbonate was seen following any of the drug treatments at the equivalent time RCBF was determined. Blood flow increased an average 36% in 37 of the 40 areas measured 1 min after heroin injection. Significant increases were found in 21 areas including visual and piriform cortex, basal ganglia, diencephalon, limbic system, midbrain tegmentum, superior colliculus, periaqueductal gray, internal capsule and fornix. These elevations in blood flow were reversed in rats receiving heroin following naloxone pretreatment. RCBF decreased in 35 areas (mean = −12%) 4 min after naloxone injection; a 40% decrease in blood flow to entorhinal cortex was significant. These results suggest that opiate receptor stimulation by heroin increases functional activity within selected brain areas, and this effect is not to regions with dense populations of opiate receptors.
Electrophysiological assay and characterization of central adrenoceptors: techniques and neuropharmacology.

Several single unit electrophysiological studies that have investigated central adrenoceptors are reviewed. The techniques and paradigms employed to electrophysiologically assay such adrenoceptors are discussed. Several regions of the brain, e.g., the nucleus locus coeruleus, the dorsal raphe nucleus, the lateral geniculate nucleus, and the cerebellar Purkinje neurons, are examined in detail, with reference to the nature of the adrenoceptor(s) located on these neurons. From the studies reviewed, it can be concluded that single unit electrophysiological recordings provide a valuable and powerful assay for adrenoceptors. Modification of this technique to study adrenoceptors from awake (behaving) or chronically treated animals is likely to result in significant advances in our understanding of mechanisms contributing to neuroreceptor plasticity.
CONTRIBUTIONS OF THE US ARMY NATICK RESEARCH AND DEVELOPMENT CENTER TO THE OBJECTIVE MEASUREMENT OF THE TEXTURAL QUALITY OF MEAT

Several approaches to the problem of objective measurement of the texture of meat, including modification of existing devices and development of new units, are presented. A mathematical-mechanical model is introduced which shows that some of the simpler tests presently used measure only part of the textural properties of meat; additional tests are needed to improve texture evaluation.
Phosphatidylinositol transfer proteins: Negotiating the regulatory interface between lipid metabolism and lipid signaling in diverse cellular processes

Phosphoinositides represent only a small percentage of the total cellular lipid pool. Yet, these molecules play crucial roles in diverse intracellular processes such as signal transduction at membrane-cytosol interface, regulation of membrane trafficking, cytoskeleton organization, nuclear events, and the permeability and transport functions of the membrane. A central principle in such lipid-mediated signaling is the appropriate coordination of these events. Such an intricate coordination demands fine spatial and temporal control of lipid metabolism and organization, and consistent mechanisms for specifically coupling these parameters to dedicated physiological processes. In that regard, recent studies have identified Sec14-like phosphatidylcholine transfer protein (PITPs) as "coincidence detectors," which spatially and temporally link the diverse aspects of the cellular lipid metabolome with phosphoinositide signaling. The integral role of PITPs in eukaryotic signal transduction design is amply demonstrated by the mammalian diseases associated with the derangements in the function of these proteins, to stress response and developmental regulation in plants, to fungal dimorphism and pathogenicity, to membrane trafficking in yeast, and higher eukaryotes. This review updates the recent advances made in the understanding of how these proteins, specifically PITPs of the Sec14-protein superfamily, operate at the molecular level and further describes how this knowledge has advanced our perception on the diverse biological functions of PITPs.
Caenorhabditis elegans operons: form and function

Nematodes are unusual among animals in having a substantial proportion of their genes arranged in polycistronic clusters that are similar to bacterial operons. Recently, a nearly complete database of the Caenorhabditis elegans genes that are transcribed in operons has been produced. Analysis of this database has identified the types of genes that are contained in the operons and the extent to which operons co-regulate genes of related function.
Fe-15Ni-13Cr austenitic stainless steels for fission and fusion reactor applications. II. Effects of minor elements on precipitate phase stability during thermal aging

The precipitate phase stability in Fe–15Ni–13Cr base austenitic alloys was investigated as a function of minor alloying additions after thermally aging at 600°C and 675°C for times ranging from 24 h to one year. Seven major precipitate phases were found in aged specimens, including M23C6, Laves, Eta (η), TiO, NbC, MC, and M2P. The types and amounts of precipitate phases varied with alloying element additions, aging temperature, and aging time. By analyzing the composition of each individual particle, it was possible to determine the essential constituent elements for each phase. From this information, a strategy to promote or suppress certain precipitate phases was developed. Among the seven phases, the most desirable precipitate phases were considered to be MC and M2P, because these particles form on a fine scale with a high number density and, therefore, can serve as effective gas atom trap sites under irradiation.
Pyrimidine nucleoside catabolism in Sphingomonas paucimobilis: role of cytidine deaminase and uridine phosphorylase.

Pyrimidine nucleoside catabolism in the human pathogen Sphingomonas paucimobilis was studied. It was observed that S. paucimobilis was only capable of utilizing cytidine or deoxycytidine as a sole nitrogen source when glucose served as the carbon source. Thinlayer Chromatographic analyses of cytidine and uridine catabolic products revealed that the enzymes cytidine deaminase and uridine phosphorylase were active in the extracts prepared from S. paucimobilis cells. The levels of cytidine deaminase and cytosine deaminase activities were lowered after growth on cytidine or deoxycytidine as a nitrogen source instead of ammonium sulfate. Uridine phosphorylase activity increased more than 4-fold after growth on deoxycytidine as a nitrogen source while growth on the nitrogen source cytidine caused a depression in phosphorylase activity.
Review: stimulants improve overt and covert aggression related behaviours in attention deficit hyperactivity disorder.

(2002) J Am Acad Child Adolesc Psychiatry 41, 253; Connor DF, Glatt SJ, Lopez ID, et al. . Psychopharmacology and aggression. I: A meta-analysis of stimulant effects on overt/covert aggression-related behaviors in ADHD. . Mar; . : . –61 . [OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4] QUESTION: In children with attention deficit hyperactivity disorder (ADHD), are stimulants more effective than placebo for improving overt and covert aggression related behaviours? Studies were identified by searching Medline (1970–2001) and by reviewing bibliographies of relevant articles. Studies in English language were selected if they were controlled trials (crossover or parallel groups) comparing stimulants with placebo, were published in peer reviewed scientific journals, reported quantitative data on independent effects for aggression related behaviours, used a rating scale or method of observation to assess aggression related behaviours, and included children or youth (mean age <18 y) with ADHD. Reports that only included effects of stimulants on the core symptoms of ADHD were excluded. Data were extracted on sample size, demographical characteristics, comorbid psychiatric disorder, key components of the intervention, duration of treatment, study quality, and outcomes. Outcomes included overt (resulting in a direct confrontation with others) and covert … [1]: {openurl}?query=rft.jtitle%253DJournal%2Bof%2Bthe%2BAmerican%2BAcademy%2Bof%2BChild%2Band%2BAdolescent%2BPsychiatry%26rft.stitle%253DJ%2BAm%2BAcad%2BChild%2BAdolesc%2BPsychiatry%26rft.aulast%253DConnor%26rft.auinit1%253DD.%2BF.%26rft.volume%253D41%26rft.issue%253D3%26rft.spage%253D253%26rft.epage%253D261%26rft.atitle%253DPsychopharmacology%2Band%2Baggression.%2BI%253A%2BA%2Bmeta-analysis%2Bof%2Bstimulant%2Beffects%2Bon%2Bovert%252Fcovert%2Baggression-related%2Bbehaviors%2Bin%2BADHD.%26rft_id%253Dinfo%253Adoi%252F10.1097%252F00004583-200203000-00004%26rft_id%253Dinfo%253Apmid%252F11886019%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.1097/00004583-200203000-00004&link_type=DOI [3]: /lookup/external-ref?access_num=11886019&link_type=MED&atom=%2Febmental%2F5%2F4%2F108.atom [4]: /lookup/external-ref?access_num=000174118400004&link_type=ISI
The Nutrition Transition: New Trends in the Global Diet

Analyses of economic and food availability data for 1962–1994 reveal a major shift in the structure of the global diet marked by an uncoupling of the classic relationship between incomes and fat intakes. Global availability of cheap vegetable oils and fats has resulted in greatly increased fat consumption among low-income nations. Consequently, the nutrition transition now occurs at lower levels of the gross national product than previously, and is accelerated further by high urbanization rates. Data from Asian nations, where diet structure is rapidly changing, suggest that diets higher in fats and sweeteners are also more diverse and more varied. Given that preferences for palatable diets are a universal human trait, fat consumption may be governed not by physiological mechanisms but by the amount of fat available in the food supply. Whereas economic development has led to improved food security and better health, adverse health effects of the nutrition transition include growing rates of childhood obesity. The implications of these trends are explored.
Impurity relaxation mechanism for dynamic magnetization reversal in a single domain grain

The interaction of coherent magnetization rotation with a system of two-level impurities is studied. Two different, but not contradictory mechanisms, the ``slow-relaxing ion'' and the ``fast-relaxing ion,'' are utilized to derive a system of integrodifferential equations for the magnetization. These expressions do not contain any phenomenological parameter and apply to any dynamic magnetization process, including complete reversal. In the case that the impurity relaxation rate is much greater than the magnetization precession frequency, these equations can be written in a form similar to the Landau-Lifshitz-Gilbert equation with damping. The damping parameter can be directly calculated from these microscopic impurity relaxation processes. A realistic estimate of the damping parameter for a magnetic nanograin is obtained.
Energy Analysis of Piezoelectric-Actuated Structures Driven by Linear Amplifiers

Energy expressions for a piezoelectric actuator coupled to a resonant mechanical load are analyzed for the purpose of determining the energy requirements of controlled structures. The analysis illustrates that the energy dissipated within the linear amplifier is a function of four parameters: the driving frequency, the piezoelectric coupling coefficient, the relative stiffness of the actuator and load, and the amplifier supply voltage. The piezoelectric actuator and the mechanical load are assumed to be lossless to highlight the relationship between energy dissipated within the amplifier and the energy stored in the actuator. For a specific frequency, the minimum energy dissipation within the amplifier is equal to twice the stored electrical energy in the piezoelectric when the amplifier voltage is equal to the driving voltage of the actuator. Additional energy is dissipated within the amplifier when the supply voltage is greater than the driving voltage. In the case when the actuator displacement is cons...
Understanding the intrinsic circuitry of the cat's lateral geniculate nucleus: electrical properties of the spine-triad arrangement.

Electron-microscopic studies of relay cells in the lateral geniculate nucleus of the cat have shown that the retinal input to X-cells is associated with a special synaptic circuitry, termed the spine--triad. The retinal afferent makes an asymmetrical synapse with both a dendritic appendage of the X-cell and a geniculate interneuron. The interneuron contacts in turn the same dendritic appendage with a symmetrical synaptic profile. The retinal input to geniculate Y-cells is predominantly found on dendritic shafts without any triadic arrangement. We explore the integrative properties of X- and Y-cells resulting from this striking dichotomy in synaptic architecture. The basis of our analysis is the solution of the passive cable equation in a HRP-stained and reconstructed geniculate X-cell with known somatic input resistance. Recent evidence shows that geniculate interneurons stain for glutamic acid decarboxylase, the synthesizing enzyme for the inhibitory neurotransmitter $\gamma $-aminobutyric acid (GABA). Under the assumption that the GABAergic inhibition has a reversal potential close to the resting potential of the cell, activation of the interneuron reduces very efficiently the excitatory postsynaptic potential induced by the retinal afferent without affecting the electrical activity in the rest of the cell. Therefore, the spine--triad circuit implements the analogue version of an AND--NOT gate. Functionally, this corresponds to a presynaptic, feed-forward type of inhibition of the optic tract terminal although inhibition actually occurs at a postsynaptic site. If the inhibition has a reversal potential well below the resting potential, the inhibitory postsynaptic potential would hyperpolarize large parts of the relay cell, abolishing the local character of the synaptic veto operation. Since Y-cells lack this structure, inhibition acts globally, reducing the general electrical activity of the cell. We propose that geniculate interneurons gate the flow of visual information into the X-system as a function of the behavioural state of the animal, enhancing the centre-surround antagonism and possibly mediating reciprocal lateral inhibition and eye-movement-related suppression.
Study to determine the ability of cortisone to sensitize the skin

Abstract A study to determine whether the human skin could be sensitized by patch test applications of cortisone yielded negative results in 44 subjects. Two procedures were employed: (1) initial prolonged patch test exposures for 3 to 7 days followed by a 7 day challenging dose, and (2) frequent, short (1 day) exposures followed by a short challenging exposure. Within the limits of the described experiments, it would appear that cortisone is not an active cutaneous sensitizer.
A Sensitivity Analysis Approach for Some Deterministic Multi-Criteria Decision-Making Methods*

Often data in multi-criteria decision making (MCDM) problems are imprecise and changeable. Therefore, an important step in many applications of MCDM is to perform a sensitivity analysis on the input data. This paper presents a methodology for performing a sensitivity analysis on the weights of the decision criteria and the performance values of the alternatives expressed in terms of the decision criteria. The proposed methodology is demonstrated on three widely used decision methods. These are the weighted sum model (WSM), the weighted product model (WPM), and the analytic hierarchy process (AHP). This paper formalizes a number of important issues on sensitivity analysis and derives some critical theoretical results. Also, a number of illustrative examples and computational experiments further illustrate the application of the proposed methodology.
AIDS Exceptionalism: Another Constituency Heard From

Amidst current debates over resources for AIDS, we examine the policy preferences of the people who are navigating AIDS in their daily lives. Survey and ethnographic data on the prioritization of HIV/AIDS interventions were collected in a longitudinal cohort study in rural Malawi. Study participants gave higher priority to problems other than AIDS. Confining analysis to HIV-positive survey respondents only weakly raises the prioritization of HIV/AIDS services. The ethnographic data are consistent with these findings: although rural Malawians are fully aware of the risk of dying from AIDS, other problems are perceived as more pressing for their community.
Analysis of Thermal Radiation Bidirectionally Reflected from Roughened Brass

Thermal radiant power (energy/time) reflected from a series of carefully prepared, roughened, brass surfaces has been investigated experimentally. The data were acquired by holding the angle of incidence constant and varying the angle of reflection. A four parameter empirical equation fits the data to within 10% for a very wide range of laboratory variables. These variables include variations in the incidence angle of from 10° to 80° and in the reflected angle from 8° to 90°. Surface roughnesses can be described as ranging from "mirror-like" to nearly "diffuse."
On the Kolmogorov-Smirnov Test for the Exponential Distribution with Mean Unknown

Abstract The standard tables used for the Kolmogorov-Smirnov test are valid when testing whether a set of observations are from a completely specified continuous distribution. If one or more parameters must be estimated from the sample then the tables are no longer valid. A table is given in this note for use with the Kolmogorov-Smirnov statistic for testing whether a set of observations is from an exponential population when the mean is not specified but must be estimated from the sample. The table is obtained from a Monte Carlo calculation.
Enhanced Heat Transfer Due to Secondary Flows in Mixed Turbulent Convection

An experimental study of the fluid flow and heat transfer phenomena associated with opposing mixed turbulent convection in vertical ducts has been conducted. The duct considered had vertical and horizontal aspect ratios of 24.4 and 9.7, respectively. The working fluid was Freon-113, providing a Prandtl number of approximately 6.5. The results showed that a number of flow bifurcations occurred. The first bifurcation observed was from parallel turbulent mean flow to a large single flow cell in the x-z plane. Further bifurcations to multiple cells and eventually pure large-scale chaos were also observed. A correlation for the enhanced heat transfer was found.
Snowbird Intergenerational Family Relationships

This qualitative study examined the family relationships of snowbirds. Interviews were conducted with 25 older adults from the Midwest who migrated seasonally to the Sunbelt. Snowbirds did not perceive their winter experience as having a negative impact on their families in any significant way. The vast majority of snowbirds expressed satisfaction with how well they maintained their intergenerational ties and holiday traditions with family while they were away. Grandchildren were very significant in the lives of snowbirds, and family change affected, but did not end, seasonal migration. Seasonal migration enhanced the opportunity for almost a fourth of the participants to spend time with children and grandchild living near their Sunbelt residence.
An atomistic view of structural and electronic properties of rare earth ensembles on Si(0 0 1) substrates

Abstract Synergistic experimental and theoretical studies of low coverage adsorption geometries of rare earth adatoms on Si(0 0 1) were performed. Density functional calculations showed charge transfer from adatoms to Si(0 0 1) and explained observed bias dependence in scanning tunneling microscopy images. Comparison of STM simulations with empty states STM data revealed a direct correlation between coverage and surface reconstructions; the (4 × 8) reconstruction is a low coverage precursor to (2 × 4) reconstruction. Charge transfer from adatom to substrate was also confirmed by Kelvin probe force microscopy; contact potential difference measurements of Dy/Si(0 0 1) reveal a 0.28 eV higher surface potential than that of (2 × 1) reconstructed Si.
Clinical observations suggesting a changing site of action during induction and recession of spinal and epidural anesthesia.

The cephalad borders of analgesia were determined 0.75 to 4 hours following the induction of spinal or lumbar epidural anesthesia. Levels thus obtained followed a straight line best described by the skin intercept of a transverse section through the trunk. They differed markedly from the dorsolaterally slanting pattern of segmental analgesia commonly associated with these blocks and observed during the onset of analgesia. There was no difference between spinal and epidural anesthesia in his regard. It is suggested that local anesthetics act first upon radicular structures and later upon structures inside the spinal cord. Because of different rates of anesthetic uptake and elimination, cord blockade becomes clinically apparent after the block of the more peripheral structures has worn off.
Gelatinization Kinetics of Starch by Using Raman Spectroscopy

After the Raman effect was discovered in 1928, Raman spectroscopy has been widely applied to the qualitative and quantitative analysis of organic, inorganic and biological systems. Especially for the study of biological compounds, Raman spectroscopy has advantages over the other spectroscopic methods. The advantages of Raman spectroscopy are the small sample requirement, the minimal interference by water, and the conformational sensitivity etc. The advantages enable Raman spectroscopy to be a promising tool for the study of starch gelatinization.
Deformation and scattering in graphene over substrate steps

The electrical properties of graphene depend sensitively on the substrate. For example, recent measurements of epitaxial graphene on SiC show resistance arising from steps on the substrate. Here we calculate the deformation of graphene at substrate steps, and the resulting electrical resistance, over a wide range of step heights. The elastic deformations contribute only a very small resistance at the step. However, for graphene on SiC(0001) there is strong substrate-induced doping, and this is substantially reduced on the lower side of the step where graphene pulls away from the substrate. The resulting resistance explains the experimental measurements.
The regulation of D2 dopamine receptor expression.

The question of whether or not there is a polymorphism in or near DRD2 which is associated with receptor density remains unanswered. Both clinical and animal data demonstrate that D 2 dopamine receptor density is highly variable among individuals; differences of more than 100% are not uncommon. Among inbred mouse strains and F 2 intercrosses produced from these strains, it appears that most of the genetic variation in receptor expression is not associated with polymorphisms in or near Drd2.
Days of miracle and wonder

Like public health, telecommunications, and the automobile before them, sensor nets will be a vehicle of social transformation. What technologies will make developing a sensor net as easy as, for example, building an Internet application? What must we do to make installing a network of sensors as simple as creating a wireless home network?
Staphylococcus epidermidis-associated enterocolitis.

Nineteen infants (mean±SD gestational age 30±2 weeks, birth weight 1.28±0.53 kg) with Staphylococcus epidemidis bacteremia were found on retrospective chart review to have had signs and symptoms of acute enterocolitis. This S. epidemidis -associated enterocolitis constituted 37% of the 51 cases of enterocolitis and 23% of the 81 cases of S. epidemidis sepsis during the study period. S. epidemidis -associated enterocolitis was relatively mild compared with other forms of enterocolitis. Although abdominal radiographs showed markedly abnormal bowel gas patterns with distended bowel loops and bowel wall edema, only one infant had pneumatosis intestinalis and none had portal venous or free intraperitoneal gas. Only three infants had neutropenia, and five had thrombocytopenia. None of these infants required surgical intervention. Although bloody stools often persisted for weeks, none of the neonates had prolonged feeding intolerance or development of a stricture. We conclude that S. epidermidis infection is commonly associated with a mild form of enterocolitis in the neonate and that this association should be considered when selecting antibiotics for therapy.
Reduction of deer browsing of Douglas-fir (Pseudotsuga menziesii) seedlings by quadrivalent selenium.

Abstract The feasibility of using selenite ion as a systemic deer repellent for the protection of Douglas-fir ( Pseudotsuga menziesii ) seedlings is evaluated. When applied to the soil, the selenite ion is absorbed by the seedling roots, transported to the foliage, and thereafter volatilized. Acute phytotoxicity is observed only when selenium foliar concentrations exceed 100 ppm, while animal repellency is demonstrated at concentrations as low as 1–2 ppm. The design of a slow release device, based on a sparingly soluble salt of selenious acid, is reported, and its evaluation in a series of field trials is described. Preliminary results indicate that statistically significant reduction of browse damage can be achieved.
Automated multifrequency measurements of the complex impedance of fast ion conductors

Abstract An automated apparatus based on phase synchronous detection has been assembled for measurements of the complex impedance of fast ion conductors. Procedures for calibration and for data acquisition and analysis are described. The relative advantages and disadvantages of this method are compared with ac bridge and pulse methods. The method is illustrated with measurements of the sodium beta-aluminas.
Videogames and Ideological Frames

Based on cognitive linguist George Lakoff's notions of metaphor and frame as the principle organizers of political discourse, this article offers an approach to analyzing political rhetoric in videogames intended to carry ideological bias. I then argue for 3 ways games function in relation to ideological frames—reinforcement, contestation, and exposition—through examples of political games (Tax Invaders), art games (Vigilance 1.0), and commercial games (Grand Theft Auto: San Andreas). I also offer thoughts on issues likely to arise from the hypothetical adoption of political frame and metaphor as design principles.
Can depression treatment in primary care reduce disability? A stepped care approach.

Objective To assess effects of stepped collaborative care depression intervention on disability. Design Randomized controlled trial. Setting Four primary care clinics of a large health maintenance organization. Patients Two hundred twenty-eight patients with either 4 or more persistent major depressive symptoms or a score of 1.5 or greater on the Hopkins Symptom Checklist. Depression items were randomized to stepped care intervention or usual care 6 to 8 weeks after initiating antidepressant medication. Intervention Augmented treatment of persistently depressed patients by an on-site psychiatrist collaborating with primary care physicians. Treatment included patient education, adjustment of pharmacotherapy, and proactive monitoring of outcomes. Main outcome measures Baseline, 1-, 3-, and 6-month assessments of the Sheehan Disability Scale and the social function and role limitation subscales of the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Results Patients who received the depression intervention experienced less interference in their family, work, and social activities than patients receiving usual primary care (Sheehan Disability Scale, z = 2.23; P =.025). Patients receiving intervention also reported a trend toward more improvement in SF-36-defined social functioning than patients receiving usual care (z = 1.63, P =.10), but there was no significant difference in role performance (z = 0.07, P =.94). Conclusions Significant disability accompanied depression in this persistently depressed group. The stepped care intervention resulted in small to moderate functional improvements for these primary care patients. Arch Fam Med. 2000;9:1052-1058
Training in Family Psychology: A Competencies‐Based Approach

After providing an overview of the family psychology landscape and the competencies-based movement in professional psychology, attention is paid to eight family-specific competencies in the following areas: the application of scientific knowledge to practice, psychological assessment, psychological intervention, consultation and interprofessional collaboration, supervision, professional development, ethics and legal issues, and individual and cultural diversity. Effective strategies for providing family-focused education and training to psychology trainees at the doctoral, internship, and postdoctoral levels and to psychologists through continuing professional education in these core competency domains are provided.
Robust Failure Detection for Reentry Vehicle Attitude Control Systems

This paper presents a robust failure detection methodology for the attitude control system of reusable launch vehicles (RLVs). In particular, we consider the problem of estimating the thrust from multiple jets e ring from an RLV reaction control system (RCS), as well as the related problem of distinguishing between failures in the RCS and the aerosurfaces. For accurately known vehicle and sensor models, the Kalman e lter provides the optimal estimate for the jet thrust, in the least-squares sense. During reentry, however, plant model uncertainties are a major problem for such a e lter as the vehicle’ s aerodynamics vary widely with rapidly changing Mach number, making gain scheduling impractical. Consequently, the Kalman e lter’ s performance degrades. Even if the Mach number were accurately known, rapid gain scheduling may not be desirable or even possible, because of the large data storage requirements it entails. Transient, robust H1 or game-theoretic e lters are proposed for nextgeneration RLV, and a prototype design is demonstrated for the Space Shuttle Orbiter’ s attitude determination system. Simulation results demonstrate that the robust e lters can be insensitive to plant model uncertainties over a much wider range of Mach numbers than a traditional Kalman e lter, while remaining sensitive to failures in the aerosurfaces and the RCS jets.
Purging flow protection of infrared telescopes

The use of a purging gas flow as a means of protecting the cryogenic optics in space infrared telescopes from condensible gaseous contaminants has been studied. The significance of both the purge/contaminant differential scattering cross section and the purge gas density distribution is analyzed. It is concluded that it is important to use the correct form of the differential scattering cross section as well as accurate purge gas density distributions when estimating the effectiveness of purging flows for contaminant protection. Experimental verification of the techniques that are used here to calculate purge gas density distributions are presented. Complete contaminant rejection from the interior of a telescope is unlikely, since for realistic purge gas densities most of the contaminants prevented from reaching the optical surfaces will condense on the telescope's internal optical baffling. Specific examples of contaminant shielding for two modes of purge gas injection are presented for the Orris I telescope. The effectiveness of helium and neon as purge gases is compared.
Production and reversal of DOCA-salt hypertension in baboons.

We describe for the first time a non-human primate model of mineralocorticoid-salt hypertension. Baboons instrumented for chronic, direct measurement of arterial pressure, underwent sodium chloride loading (8.6 or 17.1 mEq/kg/day) by different routes for several weeks and deoxycorticosterone acetate (DOCA) 5 mg/2 days i.m., in addition to sodium chloride, for periods lasting up to several months. Salt loading alone at 8.6 mEq/kg/day had no chronic effect on mean arterial pressure (MAP). Salt loading at both doses in combination with DOCA produced increases in MAP within a few days which became progressively larger over weeks to months. DOCA-salt hypertension was associated with hyporeninemia and mild hypokalemia, without consistent changes in heart rate or plasma catecholamines. A biofeedback procedure applied to three animals failed to reduce tonic blood pressure. In two of these animals, administration of clonidine or atenolol also had no antihypertensive effect, whereas a diuretic combination (hydrochlorothiazide and triamterene) rapidly abolished the hypertension. The absence of amelioration of the hypertension by a central sympatholytic agent or a beta-adrenoceptor blocker, coupled with the absence of increased plasma catecholamines, suggests that increased sympathetic activity may not contribute to the hypertension in contrast with findings in lower animals but consistent with clinical reports.
Insulin but not insulin-like growth factor-1 promotes the primordial to primary follicle transition.

A critical step in ovarian biology is the transition of the developmentally arrested primordial follicle to the growing primary follicle. The current study utilizes a rat ovarian organ culture system to investigate the role of insulin and insulin-like growth factor-1 (IGF-1) in this process. Four-day-old rat ovaries were cultured and the degree of primordial to primary follicle transition measured. Insulin increased the primordial to primary follicle transition 30% over control with a half maximal effective concentration (EC50) between 2.5 and 5 ng/ml. IGF-1 did not cause an increase in the primordial to primary follicle transition at concentrations up to 100 ng/ml. Ovaries were also treated with epidermal growth factor (EGF) and hepatocyte growth factor (HGF) and neither had an effect on the primordial to primary follicle transition. Ovaries were treated with insulin in conjunction with other factors known to promote the primordial to primary follicle transition in order to discern any potential synergistic effects. Previous experiments have shown that kit ligand (KL), basic fibroblast growth factor (bFGF) and leukemia inhibitory factor (LIF) promote the primordial to primary follicle transition. Insulin was shown to have an additive effect with KL and LIF, but not bFGF. The fact that insulin can influence the primordial to primary follicle transition at low concentrations (i.e. 5 ng/ml) and that IGF-1 has no effect suggests that insulin is acting at the insulin receptor, not the IGF-1 receptor. The observation that insulin has an additive effect with KL and LIF, but not bFGF, suggests the insulin's site of action is likely the oocyte. In summary, observations suggest that insulin acts as an endocrine type factor to help coordinate primordial to primary follicle transition at the level of the oocyte. The significance of the observations in relation to diabetes and female infertility is discussed.
Contact among families who share the same sperm donor.

Objective To examine the experience of contact among families who share the same sperm donor and the purpose served by contact. Design Study 1: retrospective survey; study 2: archival data analysis. Setting Donor insemination (DI) program. Patient(s) Study 1: 14 parents from the first cohort of matched families; study 2: Archival data about 515 families from the DI program. Intervention(s) Study 1: Interview of parents via anonymous mail-back survey; study 2: none. Main Outcome Measure(s) Study 1: Survey questions focused on the family, contact experience, and relationship to the matched family. Study 2: Comparison of families in the matching service to DI program families on family structure, parity, and type of donor (anonymous or open-identity). Result(s) Study 1: Single women and lesbian couples headed most families. Parents reported positive experiences with contact. Reasons for contact focused on creating family for the child and addressing questions about the donor. Study 2: Families with open-identity donors and those headed by single women were overrepresented in the matching service; heterosexual couple-headed families were underrepresented. Conclusion(s) Findings indicate positive outcomes for contact among families who share the same donor. Contact appears to serve the purpose of creating extended family for the child and may also help answer questions about the donor.
The General Systems Approach to the Understanding of Groups

This Sixth Annual Dorothy Nyswander Lecture was given April 13, 1962 at the School of Public Health of the University of California at Berkeley, where Dr. Nyswander was Professor of Health Education until her retirement.
Formation of a putative relaxation intermediate during T‐DNA processing directed by the Agrobacterium tumefaciens VirD1, D2 endonuclease

During the initial stages of crown gall tumorigenesis, the T-DNA region of the Agrobacterium tumefaciens Ti-plasmid is processed, resulting in the production of T-DNA molecules that are subsequently transferred to the plant cell. Processing of the T-DNA in the bacterium involves the nicking of T-DNA border sequences by an endonuclease encoded by the virD locus, and the subsequent tight (possibly covalent) association of the VirD2 protein with the 5' end of the processed single-stranded or double-stranded T-DNA molecule. To investigate the interaction of the VirD1,D2 endonuclease with a right T-DNA border, a set of plasmids containing both the border and virD sequences on the same high-copy-number replicon has been constructed and introduced into Escherichia coli. In this model system a tight nucleoprotein complex is formed between the relaxed double-stranded substrate plasmid and the VirD2 protein. This putative T-DNA processing complex may be analogous to the covalent relaxation complex formed between the pilot protein and plasmid DNA during bacterial conjugation. VirD2 attachment to the relaxed substrate plasmid was resistant to denaturing agents but sensitive to S1 nuclease digestion, indicating a single-stranded region near the site of protein attachment. We speculate that this structure may be an intermediate formed prior to T-strand unwinding from the substrate plasmid in a host bacterium.
Characterization of risk factors for Helicobacter pylori infection among men attending a sexually transmitted disease clinic: lack of evidence for sexual transmission

The mechanism of transmission of Helicobacter pylori is unknown. To investigate the role of sexual behavior and demographic factors in the acquisition of H. pylori infection, we evaluated the seroprevalence of antibody to H. pylori in 370 men attending an urban sexually transmitted diseases clinic. Sera from the following three groups were analyzed by enzyme-linked immunosorbent assay for H. pylori-specific immunoglobulin G: 78 human immunodeficiency virus (HIV)-seropositive homosexual men, 102 HIV-seronegative homosexual men, and 190 HIV-seronegative heterosexual men. Overall, the seroprevalence of H. pylori was 100 of 370 men (27%), with rates of 18% in HIV-seropositive homosexual men and 20% in HIV-seronegative homosexual men versus 35% in heterosexual men (P less than 0.005, chi 2 test). By ethnic group, 21 (12%) of 181 Caucasian men, 40 (41%) of 97 black men, and 37 (43%) of 87 Hispanic men were seropositive (P less than 0.001, chi 2 test). Multivariate analysis revealed that race was associated with H. pylori seropositivity independent of HIV status, sexual preference, or age. There was no relationship between H. pylori seropositivity and the number of lifetime sexual partners or previous sexually transmitted diseases. Three HIV-seropositive men with H. pylori immunoglobulin G had essentially identical antibody titers over 8 to 16 months of follow-up. In conclusion, black and Hispanic men have significantly higher H. pylori seroprevalence rates than do Caucasian men, but neither sexual behavior nor HIV infection influences the presence or persistence of H. pylori antibody. Further evaluation of the factors associated with these ethnic differences may lead to a better understanding of H. pylori acquisition and transmission.