cssi/SciSciGPT-SciSciNet huggingface dataset:
Evidence of Spring Spawning Lake Trout in Lake Superior

Abstract In 1992, the U. S. Fish and Wildlife Service began research on the life history, population dynamics, and stock delineation of siscowet lake trout Salvelinus namaycush siscowet in Lake Superior. Siscowet were captured with gill nets in 80-150 m of water on 23-26 April 1992 north of the Apostle Islands in western Lake Superior. Of 91 captured siscowets, one male had fully developed testes in nearly ripe condition and one female had eggs running from the vent. This observation represents the earliest dates that lake trout of any morphotype have been found in spawning or near-spawning condition.
OVARIAN INFLUENCE ON THE RESPONSE OF THE ANTERIOR PITUITARY TO ESTROGENS

There are two theories of the action of sex hormones on the gonadotrophic functionof the hypophysis. One theory is that sex hormones (estrogens or androgens) inhibit or suppress the gonadotrophic function of the hypophysis; the other is that the sex hormones stimulate the hypophysis to elaborate and release increased quantities of gonadotrophic hormone. Review of the evidence supporting these concepts indicates that one is based on the resultsof long-term experiments and the other on interpretation of short-term experiments. Long-term experiments are those in which the rats, although immature initially, reached the normal age of maturity during the course of treatment. Furthermore, since the estrous cycle of the rat is 4 or 5 days in length and the gestation period is 22 days, many of the long-term experiments exceeded these normal reproductive processes in duration. The duration of short-term experiments more closely approximates the length of the sexual cycle.
Hormonal factors controlling the development of sexual behavior in the male golden hamster

Abstract Masculine and feminine responses of male hamsters castrated on the day of birth (Day 1) and treated with androgen, estrogen or control substances on Days 2–4 were investigated. Male hamsters treated with testosterone, testosterone propionate, estradiol, estradiol benzoate, or diethylstilbestrol displayed mounting behavior after TP treatment in adulthood. Androsterone, dihydrotestosterone or control substances given neonatally failed to induce the potential for masculine sexual behavior. These data support the hypothesis that the development of masculine sexual behavior is dependent upon the presence of estrogen or androgens which can be converted to estrogen during sexual differentiation. Sexual receptivity in response to adult ovarian hormone treatment was decreased in Day 1 castrated males which received testosterone propionate or estrogens neonatally. Receptivity measures of males treated with testosterone, androsterone or dihydrotestosterone were not different from controls. Treatment of the neonatally castrated male with androgens early in life resulted in significant development of the penile bone cartilage, whereas the peripheral morphology of males treated neonatally with estrogen was not different from control males. These results indicate that alterations of peripheral morphology and mechanisms involved in the differentiation of sexual behavior may be hormone specific.
Effect of internal maxillary arterial occlusion on nasal blood flow in swine.

Objectives: The precise effects of therapeutic occlusion of the internal maxillary artery (IMA) on distal nasal mucosal perfusion are unknown. A better understanding of these effects has important implications regarding the rationale and expected efficacy of certain therapeutic interventions for epistaxis management. The authors developed an animal model to assess these issues. Study Design: The effects of “proximal” and progressively more “distal” occlusions of the IMA on nasal mucosal blood flow (NBF) were assessed in anesthetized swine using continuous laser Doppler flowmetry. The levels of arterial occlusion were selected to simulate clinical therapeutic occlusions used for the management of epistaxis. Methods: Nineteen swine were entered into one of four experimental groupings: proximal IMA occlusion using platinum micro-coils (n = 6), mid-grade distal IMA occlusion with polyvinyl alcohol particulate (PVA) suspensions (300 to 500 microns, n = 5), high-grade distal IMA occlusion with polyvinyl alcohol particulate suspensions (50 to 150 microns, n = 5), and sham control (n = 2). Results: All embolizations resulted in acute decreases in average NBF from 120 mL/min per 100 g to 40 mL/min per 100 g (P <.05 for all groups). NBF returned to baseline in all three treated groups within 2 to 8 days after therapeutic embolization, depending on the level of occlusion (coils, 2 d; mid-grade PVA, 2–3 d; high-grade PVA, 8 d). Follow-up angiography showed recanalization and collateralization as possible methods of reestablishing NBF. Conclusions: This study supports the rationale for performing distal IMA occlusion with transarterial particulate embolization, in order to provide a longer period of time of diminished NBF. This theoretically should promote hemostasis within an injured portion of the nasal mucosa by decreasing perfusion pressure within the capillary bed. However, the benefits of distal IMA embolization must be balanced against potential ischemic complications, as may be more commonly seen with high-grade particulate embolization.
Dark current analysis of InAs/GaSb superlattices at low temperatures

Abstract A limitation to the advancement of the strained-layer superlattice technology for infrared detection is unwanted high dark currents and low R 0 A values, especially at long-wavelengths. In this paper, we discuss dark current characteristics of LWIR InAs/GaSb type-II superlattice detectors. Comparing devices with different dominant mechanisms, a more thorough analysis at low temperatures is provided.
Parametric finite element analysis of verterbral bodies affected by tumors

The vertebral column is the most frequent site of metastatic involvement of the skeleton. Due to the proximity to the spinal cord, from 5% to 10% of all cancer patients develop neurologic manifestations. As a consequence, fracture risk prediction has significant clinical importance. In this study, we model the metastatically involved vertebra so as to parametrically investigate the effects of tumor size, material properties and compressive loading rate on vertebral strength. A two-dimensional axisymmetric finite element model of a spinal motion segment consisting of the first lumbar vertebral body (no posterior elements) and adjacent intervertebral disc was developed to allow the inclusion of a centrally located tumor in the vertebral body. After evaluating elastic, mixed, and poroelastic formulations, we concluded that the poroelastic representation was most suitable for modeling the metastatically involved vertebra's response to compressive load. Maximum principal strains were used to localize regions of potential vertebral trabecular bone failure. Radial and axial vertebral body displacements were used as relative indicators of spinal canal encroachment and endplate failure. Increased tumor size and loading rate, and reduced trabecular bone density all elevated axial and radial displacements and maximum tensile strains. The results of this parametric study suggest that vertebral tumor size and bone density contribute significantly to a patients risk for vertebral fracture and should be incorporated in clinical assessment paradigms.
Teachers' Undergraduate Coursework in Economics in the Baccalaureate and Beyond Longitudinal Study

The National Center for Educational Statistics' Baccalaureate and Beyond (B and B) Longitudinal Study followed a nationally representative sample of approximately 11,000 students after their graduation in the 1992-93 academic year, with interviews conducted in 1994 and 1997. Approximately 1,700 graduates reported working as teachers at some time in their careers. Using transcript data from the B and B study, the authors report the quantity and type of economics courses that these teachers completed as undergraduates and their average grades in these courses and then compare those figures to the overall B and B population.
Eosinophil-particle interactions: a model system for study of cellular adherence and activation.

Abstract In its role as an effector capable of killing large multicellular parasites, the eosinophil must be especially adapted for dealing with noningestible surfaces. A model system of Sepharose beads coated with serum protein or concanavalin A (Con A) has been used to study interactions between guinea pig peritoneal exudate eosinophils and noningestible particles. A small percentage of eosinophils were adherent to serum treated Sepharose; however, many cells were adherent to Con A-Sepharose. Adherence to Con A-Sepharose was decreased by pretreatment with 1 mM α-methylmannoside (α-MM). As compared to resting eosinophils, incubation of eosinophils with serum-treated Sepharose led to activation of oxidative metabolism as indicated by an eight-fold increase in superoxide anion production and an approximately threefold increase in quantitative leukocyte iodination. Eosinophils which were adherent to Con A beads could not be activated by either phorbol myristate acetate (PMA) or preopsonized zymosan. However, if adherence was reduced by preincubation with α-MM, PMA was able to activate the eosinophils. Neither soluble Con A nor Sepharose beads interfered with the assay of superoxide anion. These studies demonstrate the utility of Sepharose beads for studying interactions between eosinophils and noningestible particles.
Calculation of titratable acidity from urinary stone risk factors

Calculation of titratable acidity from urinary stone risk factors. Using urine samples and standard solutions, this study demonstrates that the existing procedure for measuring titratable acidity in the urine is not reliable and may result in overestimates of up to 25%. The accuracy is affected by loss of CO 2 , the presence of uric acid crystals, and the precipitation of calciumphosphate phases during the titration. A method is presented for calculating titratable acidity, using a number of routinely-measured urine components and a computer program for calculating complex equilibria in the urine. The calculated titratable acidity is shown to be more reliable then the measured one. The results are compiled in a nomogram from which the titratable acidity can be directly read. When the parameters of urine pH, PO 4 content and pCO 2 are used, the accuracy of the nomogram is > 96% for urine samples with a pH value above 6.0 and >89% for urine samples with a pH value below 6.0. For all samples, the accuracy is improved to > 97% when the nomogram using uric acid and citrate content is used in additionally.
Simulation of integrated silicon-based Ge/Si quantum-well-and-superlattice infrared photodetectors

We have performed quantum-mechanical analyses of strain- symmetrized Ge/Si QWIPs grown upon a realized buffer layer of Si0.4Ge0.6 on Si. The multi-quantum-well (MQW) QWIP has 50 angstrom-thick compressively strained p-doped Ge quantum wells and 200 angstrom-thick tensile-strained Si- rich SiGe barriers. This MQW allows shorter-wavelength IR sensing than prior-art unbuffered Si0.64Ge0.36/Si asymmetrically strained QWIPs because the valence band offsets are approximately 3x larger. We predict normal- incidence higher-temperature operation over the 1.7-to-3.8- micrometers wavelength band using the bound-to-bound and bound-to- continuum transitions HH1-SO1 and HH1-SO-C respectively. We expect that the p-i-p Ge/Si MQW pixels analyzed here can be fashioned into 2D imaging arrays, and that the arrays can be integrated monolithically with Si readout circuity. We also anticipate that multi-spectral IR imaging will be feasible by the technique of vertical epitaxial stacking of 'sub- QWIPs' within each pixel - where each sub-QWIP has a narrowband spectral response that differs from its neighbor's, and each sub-QWIP's electrical readout current is independent of its neighbor's.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Sedimentary processes across the continental rise of the southern Antarctic Peninsula

Abstract A series of large sediment mounds have been identified along the Pacific portion of the Antarctic Peninsula continental rise. These mounds are composed of sediment delivered to the continental rise during the advance and retreat of grounded ice across the shelf. The stratigraphic development of one of these sediment deposits, the Tula sediment mound, is examined to investigate how the onset of glaciation influenced the deep-sea depositional environment along this portion of the margin. The stratal relationships, associated facies distribution, and the physiography observed along the southern Antarctic margin reflect the waxing and waning of the Antarctic ice sheets; various processes erode, transport, and deposit sediment along the outer shelf, slope, and rise throughout a glacial cycle. A deep-sea erosional unconformity is apparent at the base of the Tula deposit. This surface may reflect the first onset of intensified bottom water circulation along the margin perhaps induced by the tectonic opening of the Drake Passage. The Tula sediment mound is comprised predominantly of canyon/overbank systems. Evidence for the onset of canyon cutting and the development of the thick overbank deposits (> 2 km) is found immediately above the deep-sea erosional unconformity. Relating increased canyon cutting across the continental rise to the fluctuation of ice across the shelf implies that the onset of predominantly glacial conditions commenced soon after the onset of intensified bottom water circulation along this margin. The volume of sediment associated with the Tula deposit and the apparent ‘point source’ distribution of the channel systems suggests that much sediment was transported to the slope and rise perhaps by meltwater processes through these canyons.
Democratic capitalism: Developing a conscience for the corporation

One way of ensuring that individual actions do not violate a group's moral norms is to develop within each individual a conscience. Conscience consists in the internalization or acceptance of a group's moral norms as correct and overriding one's self-interest when they conflict. Corporations as well as individuals need a conscience to monitor and control their behavior. The correlative of a personal conscience in a corporation consists in the representation of group interests in the running and managing of the firm. This means consumer and employee representation on the board of directors and management is the most effective way to promote corporate moral behavior.
Performance, Accuracy and Efficiency Evaluation of a Three-Dimensional Whole-Core Neutron Transport Code AGENT

The AGENT (Arbitrary Geometry Neutron Transport) an open-architecture reactor modeling tool is deterministic neutron transport code for two or three-dimensional heterogeneous neutronic design and analysis of the whole reactor cores regardless of geometry types and material configurations. The AGENT neutron transport methodology is applicable to all generations of nuclear power and research reactors. It combines three theories: (1) the theory of R-functions used to generate real three-dimensional whole-cores of square, hexagonal or triangular cross sections, (2) the planar method of characteristics used to solve isotropic neutron transport in non-homogenized 2D) reactor slices, and (3) the one-dimensional diffusion theory used to couple the planar and axial neutron tracks through the transverse leakage and angular mesh-wise flux values. The R-function-geometrical module allows a sequential building of the layers of geometry and automatic sub-meshing based on the network of domain functions. The simplicity of geometry description and selection of parameters for accurate treatment of neutron propagation is achieved through the Boolean algebraic hierarchically organized simple primitives into complex domains (both being represented with corresponding domain functions). The accuracy is comparable to Monte Carlo codes and is obtained by following neutron propagation through real geometrical domains that does not require homogenization or simplifications. Themore » efficiency is maintained through a set of acceleration techniques introduced at all important calculation levels. The flux solution incorporates power iteration with two different acceleration techniques: Coarse Mesh Re-balancing (CMR) and Coarse Mesh Finite Difference (CMFD). The stand-alone originally developed graphical user interface of the AGENT code design environment allows the user to view and verify input data by displaying the geometry and material distribution. The user can also view the output data such as three-dimensional maps of the energy-dependent mesh-wise scalar flux, reaction rate and power peaking factor. The AGENT code is in a process of an extensive and rigorous testing for various reactor types through the evaluation of its performance (ability to model any reactor geometry type), accuracy (in comparison with Monte Carlo results and other deterministic solutions or experimental data) and efficiency (computational speed that is directly determined by the mathematical and numerical solution to the iterative approach of the flux convergence). This paper outlines main aspects of the theories unified into the AGENT code formalism and demonstrates the code performance, accuracy and efficiency using few representative examples. The AGENT code is a main part of the so called virtual reactor system developed for numerical simulations of research reactors. Few illustrative examples of the web interface are briefly outlined. (authors)« less
Hidden agendas and ripple effects : Implications of four recent supreme Court decisions for forensic mental health professionals

Abstract Supreme Court decisions have implications far beyond the legal principles they articulate, and it is essential that individuals working in the forensic mental health and correctional systems understand the extent to which such decisions can affect their practice and the facilities in which they work. The seemingly-unrelated cases of Godi-nez v. Moran (1993) (establishing a unitary standard for the determinations of competency to plead guilty, competency to waive counsel, and competency to stand trial), Kansas v. Hendricks (1997) (upholding the constitutionality of one state's “Sexually Violent Predator Act”), Pennsylvania Department of Corrections v. Yeskey (1998) (ruling that the Americans with Disabilities Act (ADA) applies to state prisons), and Olmstead v. L.C. (1999) (finding a qualified right to community treatment for certain persons institutionalized because of mental disability) may have profound impacts on forensic mental health and correctional practices. These potential impacts, howev...
Anthesis and floral senescence in Chlorogalum pomeridianum (Liliaceae).

Flowers of the soap-plant, Chlorogalum pomeridianum (DC.) Kunth., open for a few hours on only one day. The flowers open rapidly in the late afternoon, produce nectar, and close some 6-8 hr later. As the time of anthesis nears, the tepals become contorted, and progressively larger cavities appear in the tepal mesophyll. Multicellular trichomes at the tips of the tepals increase in length, untangle, and allow the flowers to spring open. Senescence is accompanied by the breakdown of mesophyll cells and by increased ethylene production as the perianth segments twist together and become deliquescent. Anthesis has a weak but discernible rhythmic component and is strongly influenced by alternating light and dark periods. Experiments showed that the length of the uninterrupted light period is of primary importance in the control of
Macrofaunal colonization of disturbed deep-sea environments and the structure of deep-sea benthic communities

Abstract Trays of azoic sediment and organic additions were used to determine the responses of deep-sea species to disturbance at two sites and south of New England: Deep Ocean Station One (DOS 1) at 1800-m depth and Deep Ocen Station Two (DOS 2) at 3600-m depth. Species diversity was higher in the natural community at the deeper site. Rates of colonization were similar at the two sites, but slow relative to those in similar experiments conducted in shallow water. Trays of azoic sediment resting on the bottom for 5 years did not achieve the density of individuals or species found in the natural community. Species of polychaete worms in the families Spionidae, Capitellidae, and Sigalionidae were the most consistent colonists regardless of the kind of disturbance. Highest densities were achieved in patches of organic material. At the deeper DOS 2 site, densities of the sibling species of Capitella were 829 per m2 in the vicinity of wood blocks, and the dorvilleid polychaete, Ophryothrocha sp. A, occurred dat 1274 per m2 in natural, patchy accumulations of decomposing seaweed, Sargassum. The response to disturbance represented by the sediment trays was much more variable at DOS 2 than at DOS 1, with several taxa achieving high densities in only one tray. Pholoe anoculata, Ophelina cylindricaudata, and Hesionidae spp. were consistent colonists of the sediment trays at DOS 1. A few taxa such as Capitella spp., Myriotrochus spp. and Ophiura ljungmani increased greatly under screens. Predators excluded by the screens in these experiments may normally prevent juveniles of these species from becoming abundant. Occasional escape from predation may explain the rare instances of dense populations of these species. The responses of deep-sea populations to Sargassum, wood and azoic sediments indicate that a temporal mosaic of small-scale patches of organic enrichment and disturbance are very important in structuring deep-sea communities. The high diversity of species in the deep sea is maintained by: (1) patchiness of organic input against a background of low productivity; (2) sporadic, small-scale, discrete disturbance events occurring against a background of relative constancy; (3) the lack of barriers to dispersal among populations distributed over an enormous area.
Parameters for evaluation of viability assays: Accuracy, precision, specificity, sensitivity, and standardization

The selection of appropriate viability assays is critical in evaluating the efficacy of any cryopreservation procedure. The appropriateness of a given assay depends on the specific tissue and the function which is being optimized. Although a broad range of "viability" assays have been used, these assays can be classified in seven principle groups: (i) Morphological procedures, including routine histology, surface antigen localization, and transmission electron or scanning microscopy; (ii) proliferation studies; (iii) metabolic assays; (iv) implantation; (v) mechanical assays; (vi) motility; and (vii) DNA or RNA synthetic assays. Regardless of the class of assay, each assay may be further characterized as qualitative, quantitative, or quantal and each type may vary in the degree of subjectivity. In selecting a specific viability assay, biological variability, assay bias, and the statistical probability of both Type I and Type II errors should be considered crucial. Here we discuss a number of critical factors involved in validating viability assays, including accuracy, precision, standardization, specificity, sensitivity, selection of statistical methodology, and range of the assay.
Curriculum, equipment and student project outcomes for mechatronics education in the core mechanical engineering program at Kettering University

Abstract Following an NSF grant in 1997 to develop undergraduate mechatronics laboratories and courses, two senior-level elective courses were introduced in the mechanical engineering curriculum at Kettering University. The student popularity of the subject, and relevance to graduating mechanical engineers soon made it clear that mechatronics education belonged to the core curriculum at Kettering. To integrate mechatronics into the mechanical engineering core, two existing sophomore-level courses were redesigned to include significant educational experiences in mechatronics design and prototype fabrication. Introduction to Design (ME-203) previously featured a 6-week student project in which teams of students would design and build an electromechanical device to accomplish functionality defined in design constraints provided by the professor. However, these devices were not mechatronic in nature. In the revised course, the objective is to evolve these designs to utilize embedded microcontrollers, sensors and actuators and achieve much more sophisticated functionality. To accommodate the anticipated increase in time required to complete such projects, the existing sophomore course Instrumentation (ME-204) was revised to incorporate learning objectives from the senior-level mechatronics elective courses. Further, 6 weeks of laboratory time from Instrumentation could then be dedicated to the aforementioned mechatronic projects. As such, both ME-203 and ME-204 have been integrated to form an eight-credit “Introduction to Mechatronics Design” course. This paper details the scope of this course, the specialized equipment developed for it and student project outcomes.
The Eye Regards Itself: Benefits and Challenges of Reflexivity in Qualitative Social Work Research

Much has been written about the central role of reflexivity in qualitative research, yet there has been no empirical study of how researchers actually practice reflexivity and what it is like for them to do so. To address this question, a project was developed to gather information directly from qualitative social work researchers about the perceived benefits, challenges, and limitations of reflexivity. Participants, representing eight countries with the majority (65%) from the United States, included researchers using diverse methods with varying degrees of experience. In their interviews, these 34 scholars discussed the benefits of reflexive activities for both themselves and their research projects; obstacles that were personal, project-related, professional, and systemic; a discrepancy between valuation and actual use of reflexive practices; and the need to balance flexibility and rigor. The article concludes with directions for further inquiry and suggestions for assessing the adequacy of reflexivity in published studies.
A THERMODYNAMICALLY INDUCED FINITE-AMPLITUDE CONVECTIVE INSTABILITY IN STELLAR ENVELOPES

Stellar envelopes are subject to a finite-amplitude convective instability that originates with the reduction in the adiabatic exponent Γ1 = ad accompanying partial ionization of the principle plasma constituents, notably hydrogen. The instability is one-sided; low-Γ1 perturbations are unstable, while high-Γ1 perturbations are stable. Since a partially ionized fluid has a lower adiabatic exponent than either a fully recombined or fully ionized one, convective downflows are stabilized in the upper regions of a convective envelope where the nearly fully recombined fluid is embedded in a partially ionized background. They are significantly destabilized at a depth, however, where the partially ionized downflowing fluid has a lower Γ1 than does the highly ionized mean state. Convective upflows, by contrast, are stabilized at a depth where their fully ionized state contrasts with the partially ionized background and are destabilized only in the very upper layers where the mean state of the fluid is nearly fully recombined and the upflows are partially ionized. This Letter illustrates the instability mechanism, its finite-amplitude character, and its possible significance to both idealized compressible convection simulations and the solar convective envelope.
Variation with season and with polymerized ragweed immunotherapy in IgE against ragweed antigen E in plasma and eluted from the basophil surface in patients with ragweed pollenosis

Sixteen patients with ragweed pollenosis were studied immediately before and after the 1979 ragweed season with measurement of total plasma IgE, specific plasma IgE against ragweed antigen E (IgE-a-AgE), molecules of IgE-a-AgE eluted per basophil, total antibody binding of AgE (blocking antibody), and maximum percentage histamine release in response to AgE. Thirteen received immunotherapy with polymerized ragweed and the measurements were repeated just before and after 1980 ragweed season. The patients kept symptom score diaries for each ragweed season. With season before immunotherapy, plasma IgE-a-AgE and total IgE rose. The ratio of specific to total IgE has been demonstrated to correlate with the IgE-a-AgE molecules eluted per basophil. This ratio, molecules of IgE-a-AgE eluted per basophil, and histamine release did not change. With immunotherapy, there was a significant decrease in symptom scores and a marked increase in blocking antibody. Specific IgE in plasma remained the same as total IgE fell from October 1979 to July 1980. Thus, there was a modest increase in ratio and in the number of IgE-a-AgE molecules eluted per basophil. With these changes, there was no alteration of histamine release. With season, after immunotherapy, there was not significant change in any parameter measured.
Treatment of hepatitis C with milk thistle

In a hypothetical case, a 35-year-old female presents to the pharmacy for a refill of her prescription oral contraceptive. She also asks about taking milk thistle. She states that several members of her “liver disease support group” are using the herbal supplement. She has recently been diagnosed with chronic hepatitis C and is currently receiving interferon alfa-2b and ribivarin. Her past history is significant for illegal drug and alcohol abuse in her early twenties.
Regulation of membrane associated protein kinase C activity by guanine nucleotide in rabbit peritoneal neutrophils.

Abstract Evidence is shown that protein kinase C is the major kinase which can phosphorylate histone H-1 in a membrane fraction prepared from rabbit peritoneal neutrophils. Addition of phorbol-12-myristate-13-acetate (PMA) (0.1μg/ml) or guanosine-5′-(3-O-thio)triphosphate (GTPγS) (10μM) to the membrane fraction results in an increase of the phosphorylation of histone H-1. To achieve this effect, calcium (20μM) is required for GTPγS but not for PMA. The effect of GTPγS, but not PMA is inhibited in membranes obtained from cells pretreated with pertussis toxin. The kinase activity is also enhanced by treatment of the membrane with 10μM of GppNHp or GTP but not with GDP, GMP, cGMP, ATP, ADP, AMP and cAMP. This is the first direct evidence that a GTP binding protein is involved in the activation of membrane associated protein kinase C.
Supersonic jet epitaxy of silicon carbide on silicon using methylsilane

Abstract Cubic SiC thin films have been epitaxially grown on silicon substrates using the single source precursor methylsilane (H3Si–CH3). Single phase films were grown by supersonic jet epitaxy (SJE) at temperatures as low as 560°C on Si(111) and 600°C on Si(001). Growth rates and crystal quality were found to be strongly dependent on substrate temperature and methylsilane kinetic energy. Films were characterized by X-ray diffraction (XRD) and cross-sectional transmission electron microscopy (XTEM).
Biofilm formed by a hypervirulent (hypermucoviscous) variant of Klebsiella pneumoniae does not enhance serum resistance or survival in an in vivo abscess model

A new hypervirulent (hypermucoviscous) clinical variant of Klebsiella pneumoniae (hvKP) has emerged over the last decade. Our goal is to identify new mechanisms, which increase the virulence hvKP. It has been shown that hvKP strains produce more biofilm than "classical" stains of K. pneumoniae, therefore we hypothesized that biofilm formation may contribute to the pathogenesis of systemic infection. To test this hypothesis, transposon mutants of the model pathogen hvKP1 were generated and screened for decreased production of biofilm. Three mutant constructs with disruptions in glnA [putatively encodes glutamine synthetase, hvKP1 glnA:: EZ::TN (glnA::Tn)], sucD [putatively encodes succinyl-CoA synthase α subunit, hvKP1 sucD:: EZ::TN (sucD::Tn)], and tag [putatively encodes transcriptional antiterminator of glycerol uptake operon, hvKP1 tag:: EZ::TN (tag::Tn)] were chosen for further characterization and use in biologic studies. Quantitative assays performed in rich laboratory medium and human ascites confirmed the phenotype and a hypermucoviscosity assay established that capsule production was not affected. However, compared with its wild-type parent, neither planktonic cells nor biofilms of glnA::Tn, sucD::Tn and tag::Tn displayed a change to the bactericidal activity of 90% human serum. Likewise, when assessed in a rat subcutaneous abscess model, the growth and survival of glnA::Tn, sucD::Tn and tag::Tn in abscess fluid was similar to hvKP1. In this report we identify three new genes that contribute to biofilm formation in hvKP1. However, decreased biofilm production due to disruption of these genes does not affect the sensitivity of these mutant constructs to 90% human serum when in planktonic form or within a biofilm. Further, their virulence in an in vivo abscess model was unaffected.
Efficacy of Nifekalant Hydrochloride in the Treatment of Fatal Ventricular Arrhythmia in Patients With Ischemic Heart Disease

Ventricular tachycardia (VT), which causes hemodynamic instability, and ventricular fibrillation (VF) sometimes occur in patients with severe underlying cardiovascular disease such as myocardial ischemia or infarction, and are associated with high mortality. This report presents the efficacy of nifekalant hydrochloride (nifekalant), a pure class III antiarrhythmic agent, in treating life-threatening ventricular arrhythmia in such patients. From June 2000, when nifekalant became commercially available in Japan, to May 2003, 30 ischemic heart disease (IHD) patients with VT/VF resistant to direct-current (DC) countershock received nifekalant in our hospital. These 30 patients served as the nifekalant group in this study. As a control group, we also included 33 IHD patients with VT/VF that had been resistant to DC countershock upon or during hospitalization between January 1996 and May 2000 before nifekalant became commercially available. No significant differences were observed in patient background factors and treatments between the two groups. The rates of death within 48 hours of occurrence of VT/VF were significantly lower in the nifekalant group (7%, 2/30) than in the control group (27%, 9/33; P < 0.03). The rates of cardiac death during hospitalization were also significantly lower in the nifekalant group (40%, 12/30) than in the control group (67%, 22/33; P < 0.03). The rates of survival until hospital discharge were significantly higher in the nifekalant group (57%, 17/30) than in the control group (30%, 10/33; P < 0.03). Multivariate analysis of all 63 patients revealed nifekalant administration was the factor that significantly improved the mortality (odds ratio for cardiac death, 0.26; 95% confidence interval (CI), 0.07 to 0.95; P = 0.041). Nifekalant improves the prognosis for life-threatening ventricular arrhythmia in IHD patients.
Genomic variation and adaptation in Africa: implications for human evolutionary history and disease

Africa contains the greatest levels of human genetic variation and is the source of the worldwide range expansion of all modern humans. However, relatively little is known about genomic variation in ethnically diverse African populations. Knowledge of genetic structure within Africa has important implications for the design and implementation of disease association studies in Africans and in African Americans, and for reconstructing modern human origins. In addition, studies of genetic adaptation in Africa have important implications for identifying genes that play an important role in human evolution and disease. The African populations included in this study practice diverse subsistence patterns and have diverse diets (e.g. the study includes hunter-gatherers, pastoralists, agriculturalists and agro- pastoralists). The populations studied live in diverse environments with differing pathogen exposure (tropical forest, savannah, coastal, desert, low altitude and high altitude) and, therefore, are likely to have experienced local adaptation. In this talk I will discuss results of analyses of genome-scale microsatellite and SNP genotyping data in a large set of geographically, linguistically and ethnically diverse African populations, as well as locus- specific analyses of genes that play a role in adaptation to diet and infectious disease. Implications for future whole genome sequencing analyses will be discussed.
GROWTH EFFECT AND TISSUE DISTRIBUTION OF VITAMIN A FOLLOWING INTRAVENOUS INJECTION OF VITAMIN A-RICH CHYLE.

SummaryIntravenous injection of vitamin A in the form of rat chyle into vit A-deficient assay rats produced a growth response twice that produced by the same dose given orally. The characteristic vit A auto-fluorescence was absent from the parenchy-mal cells of liver and adrenal cortex of assay rats depleted of vit A; the autofluorescence was restored to the distribution in these tissues characteristic of the normally fed rat only after intravenous injection of rat chyle which contained vit A. In contrast, intravenous injection of artificial emulsions which contained vit A resulted in a marked localization of vit A fluorescence in the reticulo-endo-thelial cells of spleen, lungs and liver and to a smaller extent in the liver and adrenal parenchymal cells. Most of the vit A content of rat plasma has been reported to be in the soluble fraction; however, we found most of the vit A content of post-absorptive rat chyle in the chylomicron fraction.
Technological Change and Spatial Transformation in an Information Economy: 2. The Influence of New Information Technology on the Urban System

A model of the urban system in the new era of information technology is developed by the introduction of new concepts and new variables to location theory. By use of the model one can generate different urban configurations and can bring differentiation to different locations, as opposed to traditional models which cannot explain the spatial structure of the contemporary urban system. It is shown that as concentrations get economically disadvantaged by congestion, information technology will facilitate a dispersal to the fringe and to rural areas.
On the transferability of atomic solvation parameters: Ab initio structural prediction of cyclic heptapeptides in DMSO.

A statistical mechanics methodology for predicting the solution structures and populations of peptides developed recently is based on a novel method for optimizing implicit solvation models, which was applied initially to a cyclic hexapeptide in DMSO (C. Baysal and H. Meirovitch, Journal of American Chemical Society, 1998, vol. 120, pp. 800–812). Thus, the molecule has been described by the simplified energy function Etot = EGRO + ∑k σkAk , where EGRO is the GROMOS force-field energy, σk and Ak are the atomic solvation parameter (ASP) and the solvent accessible surface area of atom k, respectively. In a more recent study, these ASPs have been found to be transferable to the cyclic pentapeptide cyclo(D-Pro1–Ala2–Ala3–Ala4–Ala5) in DMSO (C. Baysal and H. Meirovitch, Biopolymers, 2000, vol. 53, pp. 423–433). In the present paper, our methodology is applied to the cyclic heptapeptides axinastatin 2 [cyclo(Asn1–Pro2–Phe3–Val4–Leu5–Pro6–Val7)] and axinastatin 3 [cyclo(Asn1–Pro2–Phe3–Ile4–Leu5–Pro6–Val7)], in DMSO, which were studied by nmr by Mechnich et al. (Helvetica Chimica Acta, 1997, vol. 80, pp. 1338–1354). The calculations for axinastatin 2 show that special ASPs should be optimized for the partially charged side-chain atoms of Asn while the rest of the atoms take their values derived in our previous work; this suggests that similar optimization might be needed for other side chains as well. The solution structures of these peptides are obtained ab initio (i.e., without using experimental restraints) by an extensive conformational search based on EGRO alone and E, which consists of the new set of ASPs. For E, the theoretical values of proton–proton distances, 3J coupling constants, and other properties are found to agree very well with the nmr results, and they are always better than those based on EGRO. © 2000 John Wiley & Sons, Inc. Biopoly 54: 416–428, 2000
Hunter-gatherer populations and archaeological inference

Abstract Human local populations differ in the extent to which social relationships are diffused over large areas or are condensed into semi‐discrete clusters. This dimension of structuring is reflected in the amounts of local genetic variability, of dialect variability, and in stylistic variability of archaeological remains over the area. Because of the nature of the resources exploited, hunter‐gatherers have a very diffuse patterning of social relationships, resulting in little genetic differentiation (low inbreeding) and stylistic uniformity in artefacts over large areas.
Reliability of Fine Needle Aspiration for Thyroid Nodules Greater Than or Equal to 4 Cm

Abstract Background Fine-needle aspiration (FNA) is considered the diagnostic test of choice in the evaluation of thyroid nodules. Some practice recommendations, however, suggest surgical resection of larger thyroid nodules due to concerns of FNA unreliability in the diagnosis of thyroid malignancy. The purpose of this study was to determine the reliability of FNA in thyroid nodules ≥4 cm. Methods Retrospective review of prospectively collected data of 1068 consecutive patients who underwent FNA and thyroidectomy at a single tertiary medical center from 2003 to 2010 was performed. Patients were divided into two groups: those patients with a dominant thyroid nodule ≥4 cm ( n = 212) and those patients with a dominant thyroid nodule n = 856). Sensitivity, specificity, and negative and positive predictive values were calculated for FNA results and final histopathology after thyroidectomy. Results Of 212 patients with lesions ≥4 cm, 35% had thyroid malignancy on final pathology. Conversely, 54% of 856 patients with dominant thyroid nodules Conclusions The reliability of FNA as a diagnostic test is not affected by the size of thyroid nodules. Routine surgical resection for all thyroid nodules ≥4 cm should not be used as the only independent factor in determining need for surgical resection.
Sorption of trihalomethanes in foods

Trihalomethanes (THMs, namely, CHCl(3), CHCl(2)Br, CHClBr(2) and CHBr(3)) are disinfection by-products that are present in drinking water. These toxic chemicals are also present in meat, dairy products, vegetables, baked goods, beverages and other foods, although information regarding their concentrations and origin is very limited. This study investigates sorption of THMs occurring during rinsing and cooking of foods and the significance of food as an exposure source. Initial estimates of THM uptake were measured in experiments representing rinsing with tap water at 25 C using nine types of food, and for cooking in tap water at 90 C for fourteen other foods. A subset of foods was then selected for further study over a range of THM concentrations (23.7-118.7 microg/l), temperatures (25 C and 90 C), food concentrations (0.2-1.4, food weight: water weight), and contact times (5-240 min). Data were analyzed using regression and exponential models, and diffusion models were used to help explain the trends of THM uptake. Among vegetables, sorbed THM concentrations at 25 C were 213 to 774 ng/g for CHCl(3), 53 to 609 ng/g for CHCl(2)Br, and 150-845 ng/g for CHClBr(2). Meats at 90 C tended to have higher concentrations, e.g., 870-2634 ng/g for CHCl(3). Sorbed concentrations increased with contact time and THM concentration, and decreased with food concentration in rinsing tests (using spinach, iceberg-head lettuce and cauliflower) and cooking tests (using tomato, potato, beef and miso-tofu soup). For most foods, THM uptake was diffusion limited and several hours were needed to approach steady-state levels. Swelling, hydrolysis and other physical and chemical changes in the food can significantly affect sorption. Screening level estimates for CHCl(3) exposures, based on experimental results and typical food consumption patterns, show that uptake via foods can dominate that due to direct tap water consumption, suggesting the importance of sorption and the need for further evaluation of THM intake due to foods.
Skin Impedance and Phase Angle as a Function of Frequency and Current

The impedance of the human skin decreased from approximately 130 to 30 Kohm as the frequency of a-c input increased from 1 to 1000 cycles per second. Over this same range of frequencies, the phase angles changed from -2 to -58 degrees. Changing the peak-to-peak current through the subject from 14 to 62 microamperes had no effect or the phase angles.
Environmentally conscious redesign of turbine blade fixtures

This paper examines the re-design of turbine blade fixtures for the plasma spray coating process. The plasma spray process is used to apply a ceramic coating to turbine blades prior to gas turbine engine assembly. Without the ceramic coating, the blades would fail under the high temperatures produced during combustion. As a result, the plasma spray process is essential to modern gas turbine engines; the process as is stands, however, is environmentally expensive. Turbine blade holding fixtures are an integral part of the coating process, to both hold the blades within the furnace, and to protect precision assembly features on the root section of the turbine blade. In addition to the fuel costs and safety problems associated with the high temperature furnace, an environmentally hazardous acid bath is used to strip the ceramic coating from the fixtures to allow reuse. This acid bath is costly in terms of both production and the environment. The fixture redesign examines the functionality of the existing fixture design using a combination of classical, design for manufacturing, and axiomatic design methodologies, and develops a new design to eliminate the need for the acid bath. The new design also improves the productivity and safety of the plasma spray coating process. A prototype for the new design has been constructed and tested. The paper also discusses the economic benefits of the improved fixture design.
Mixture experiments in the interior: Yantram designs

We introduce a very rich class of mixture designs in the interior of the simplex, which are useful when all experiments must constitute a complete mixture, that is, when none of the components is absent from the mixture. These designs are called yantram designs, as they are directly derivable from the Hindu yantrams, which are certain numerical configurations of positive integers having certain properties. Not only do these designs work well within the interior of the simplex, they can also be easily refined to satisfy the constraints, if there are any, on the mixture components. Leverage values for such designs are more evenly distributed among interior points compared to simplex-lattice or simplex-centroid designs, which tend to place higher leverages on the vertices or edge design points where the experiments may not be feasible.
A note on the history force on a spherical bubble at finite Reynolds number

An approximate expression for the history force on a spherical bubble is proposed for finite Reynolds number, Re. At small time, the history‐force kernel is a constant, which decreases with increasing Re, and the kernel decays as t−2 for large time. For an impulsively started flow over a bubble, accurate finite difference results show that the history force on the bubble decays as t−2 at large time. Satisfactory agreement is observed between the presently proposed history force and the numerical solution.