cssi/SciSciGPT-SciSciNet huggingface dataset:
Bovine erythrocyte superoxide dismutase. Subunit structure and sequence location of the intrasubunit disulfide bond.

The subunit assembly of bovine erythrocyte superoxide dismutase has been studied, through analysis of the effects of heat, removal of metal ion cofactors, and disulfide bond reduction, upon the dissociation of the subunits. Investigations utilizing sodium dodecyl sulfate-acrylamide gel electrophoresis and sedimentation equilibrium analysis demonstrate that the 2 polypeptide subunits of the protein are not covalently joined, but are associated through unusually strong noncovalent interactions. This absence of intersubunit disulfide bonds, in conjunction with the titration of a single free sulfhydryl group per subunit polypeptide chain, necessitates that the 3 half-cystine residues per subunit exist as 1 residue of cystine, forming an intrasubunit disulfide bond, and 1 residue of cysteine. The specific half-cystine residues participating in the disulfide linkage and contributing the free thiol function were identified. Analysis of the products of cyanogen bromide cleavage, with acrylamide gel electrophoresis, demonstrates that the intrasubunit disulfide links 1 half-cystine residue in the sequence NH2-terminal to Met-115, to another half-cystine residue in the sequence COOH-terminal to Met-115. Through conventional procedures of enzymatic digestion, peptide isolation, and peptide characterization, Cys-55 and Cys-144 are shown to participate in the intrasubunit disulfide linkage, and Cys-6 to exist as free cysteine.
Autonomous mobile robot motion planning enhanced with extended configuration-space and half-planes

It is commonly argued that C-space buffering is too computationally expensive, consumes too much free space, keeps the robot too close to objects, seals off marginally traversable regions and does not allow for curved path segments. However, the research described in this paper uses half-planes and doors to extend C-space so that mobile robot global motion planning is not only safe and fluid, but also unhindered by tight passageways. Further, it is shown that free space consumption is limited to only what the robot needs to circumnavigate known obstacles. >
Effect of liquid addition on the bulk and flow properties of fine and coarse glass beads

The effect of water on the packing and flow properties of fine and coarse particles was experimentally investigated. Four different particle sizes of glass beads, from 5 to 275 μm, were studied with increasing water weight-percentages. Using a FT4 Powder Rheometer, changes in bulk properties were collected as a function of water content and particle size. The results show that water content plays a significant role on the packing and flow of the particles. Small amounts of water created porous aggregates due to liquid bridging. Greater amounts of water resulted in the filling of the void-spaces. This was indicated by an increase in basic flow energy, density, and pressure drop, with a decrease in porosity. A greater understanding of bulk properties of wetted material is useful to develop standard systems that can be used to examine the behavior of more complex situations, and implement changes to improve materials handling and processing. © 2015 American Institute of Chemical Engineers AIChE J, 62: 648–658, 2016
In vitro effect of mercury and cadmium on brain Ca2+-ATPase of the catfish Ictalurus punctatus.

Freshwater teleosts possess a calcium activated adenosine triphosphatase in the gills and brain which has an important role in calcium metabolism. Earlier studies have demonstrated that pesticides are found to inhibit the Ca/sup 2 +/-ATPase activity in the gills of fish. Although heavy metals have been shown to affect Na/sup +/-K/sup +/-ATPase in the brain and Ca/sup 2 +/-ATPase in the gills of fish, the mode of action of heavy metals on fish brain Ca/sup 2 +/-ATPase has not been clearly understood to date. Since heavy metals are known to produce neurotoxic action in higher vertebrates, the disruptive action of heavy metals on calcium pump in fish brain could be explained if they were found to affect this enzyme. Hence, this study was undertaken to evaluate the in vitro effect of divalent metals, mercury and cadmium on Ca/sup 2 +/-ATPase in the brain of catfish, Ictalurus punctatus.
Protective effects of adenosine in myocardial ischemia.

Adenosine is released from the myocardium in response to a decrease in the oxygen supply/demand ratio, as is seen in myocardial ischemia; its protective role is manifested by coronary and collateral vessel vasodilation that increase oxygen supply and by multiple effects that act in concert to decrease myocardial oxygen demand (i.e., negative inotropism, chronotropism, and dromotropism). During periods of oxygen deprivation, adenosine enhances energy production via increased glycolytic flux and can act as a substrate for purine salvage to restore cellular energy charge during reperfusion. Adenosine limits the degree of vascular injury during ischemia and reperfusion by inhibition of oxygen radical release from activated neutrophils, thereby preventing endothelial cell damage, and by inhibition of platelet aggregation. These effects help to preserve endothelial cell function and microvascular perfusion. Long-term exposure to adenosine may also induce coronary angiogenesis.
An Ionization Profile Monitor for the Brookhaven AGS

A non-destructive internal emittance device has been built for the AGS, with separate units to measure the horizontal and vertical profiles of the circulating beam. Positive ions from collisions of the beam with background gas are collected in a 3-kV/cm electric field onto a 64-channel parallel strip detector. Because positive ions rather than electrons are collected, profile broadening due to space charge is small. Tests indicate that a quantitative, reproducible and accurate measurement of beam size throughout the acceleration cycle is provided.
LPS-induced suppression of gastric motility relieved by TNFR:Fc construct in dorsal vagal complex

Our previous studies suggested that the cytokine tumor necrosis factor-α (TNF-α) may act within the neural circuitry of the medullary dorsal vagal complex (DVC) to affect changes in gastric functio...
The accuracy of surface elevations in forward global barotropic and baroclinic tide models

Abstract This paper examines the accuracy of surface elevations in a forward global numerical model of 10 tidal constituents. Both one-layer and two-layer simulations are performed. As far as the authors are aware, the two-layer simulations and the simulations in a companion paper (Deep-Sea Research II, 51 (2004) 3043) represent the first published global numerical solutions for baroclinic tides. Self-consistent forward solutions for the global tide are achieved with a convergent iteration procedure for the self-attraction and loading term. Energies are too large, and elevation accuracies are poor, unless substantial abyssal drag is present. Reasonably accurate tidal elevations can be obtained with a spatially uniform bulk drag c d or horizontal viscosity K H , but only if these are inordinately large. More plausible schemes concentrate drag over rough topography. The topographic drag scheme used here is based on an exact analytical solution for arbitrary small-amplitude terrain, and supplemented by dimensional analysis to account for drag due to flow-splitting and low-level turbulence as well as that due to breaking of radiating waves. The scheme is augmented by a multiplicative factor tuned to minimize elevation discrepancies with respect to the TOPEX/POSEIDON (T/P)-constrained GOT99.2 model. The multiplicative factor may account for undersampled small spatial scales in bathymetric datasets. An optimally tuned multi-constituent one-layer simulation has an RMS elevation discrepancy of 9.54 cm with respect to GOT99.2, in waters deeper than 1000 m and over latitudes covered by T/P (66 ∘ N to 66 ∘ S). The surface elevation discrepancy decreases to 8.90 cm (92 percent of the height variance captured) in the optimally tuned two-layer solution. The improvement in accuracy is not due to the direct surface elevation signature of internal tides, which is of small amplitude, but to a shift in the barotropic tide induced by baroclinicity. Elevations are also more accurate in the two-layer model when pelagic tide gauges are used as the benchmark, and when the T/P-constrained TPXO6.2 model is used as a benchmark in deep waters south of 66 ∘ S. For Antarctic diurnal tides, the improvement in forward model elevation accuracy with baroclinicity is substantial. The optimal multiplicative factor in the two-layer case is nearly the same as in the one-layer case, against initial expectations that the explicit resolution of low-mode conversion would allow less parameterized drag. In the optimally tuned two-layer M 2 solution, local values of the ratio of temporally averaged squared upper layer speed to squared lower layer speed often exceed 10.
Effect of Trapped Particles on the Nonlinear Evolution of a Wave Packet

We present numerical simulations of the evolution of a large-amplitude electrostatic wave packet in a hot collisionless plasma. When resonant particles are trapped by the wave potential during a transit time, the number of lobes in the packet is observed to increase. This is explained in terms of an equation of propagation for the packet amplitude and a dispersion relation involving the trapped particles.
Reduced activity of tryptophan 2,3-dioxygenase in the liver of rats treated with chlorinated dibenzo-p-dioxins (CDDs): Dose-responses and structure-activity relationship

Abstract The activity of tryptophan 2,3-dioxygenase (TdO) was measured in the livers of male Sprague-Dawley rats after acutely toxic doses (LD 20 –LD 80 ) of chlorinated dibenzo- p -dioxins (CDDs) with 4 of the up to 7 chlorine substituents occupying the 2,3,7,8-positions. Treatment with toxic doses of CDDs results in voluntary feed refusal of rats. A corresponding involuntary reduction of feed intake in naive animals (pair-feeding) causes elevated levels of TdO activity. In the CDD treated rats, however, TdO activities were dose-dependently reduced. An LD 80 reduced TdO activity to about 50% of the level found in the corresponding pair-fed animals. This decrease of TdO activity explains the dose-dependent increase of serum tryptophan, which in turn is the likely cause of voluntary feed refusal observed in CDD-treated rats. The activity of another enzyme which is regulated in a fashion very similar to that of TdO, viz., tyrosine aminotransferase (TAT), was consistently, but not dose-dependently, affected by treatment with CDDs.
Experimental hypertension elicited by injections of methyl cellulose.

Des injections sous-cutanes d'une solution de methyl-cellulose provoquent dans la rate une vraie hypertension arterielle maligne. Les animaux utilises eurent frequemment des œdemes et des ascites et toujours des lesions arterielles dans le cœur, les reins et ailleurs.
Mt. St. Helens: evidence of increased magmatic gas component

Abstract This paper presents measurements of SO 2 flux and ash leachate chemistry from Mt. St. Helens volcano during the period May 18 to July 22 which are in contrast to similar data from before May 18. Comparison of post-18 May SO 2 data with similar data from other volcanoes leads to the conclusion that between 15 and 25 May the SO 2 flux reached typical magmatic levels. Ash leachate chemistry from the eruption of 18 May, 22 June and 22 July also indicate a large magmatic gas component. Concentrations of Cl − and SO 2− 4 on May 18 ash increase with distance from the volcano and decrease with time. Leachate chemistry is used to estimate that a minimum of 2.4 × 10 5 tons of S were released on May 18. Low F concentrations on the ash, though increasing, present to health hazards.
Horizontal Transmission of Candida albicans and Evidence of a Vaccine Response in Mice Colonized with the Fungus

Disseminated candidiasis is the third leading nosocomial blood stream infection in the United States and is often fatal. We previously showed that disseminated candidiasis was preventable in normal mice by immunization with either a glycopeptide or a peptide synthetic vaccine, both of which were Candida albicans cell wall derived. A weakness of these studies is that, unlike humans, mice do not have a C. albicans GI flora and they lack Candida serum antibodies. We examined the influence of C. albicans GI tract colonization and serum antibodies on mouse vaccination responses to the peptide, Fba, derived from fructose bisphosphate aldolase which has cytosolic and cell wall distributions in the fungus. We evaluated the effect of live C. albicans in drinking water and antimicrobial agents on establishment of Candida colonization of the mouse GI tract. Body mass, C. albicans in feces, and fungal-specific serum antibodies were monitored longitudinally. Unexpectedly, C. albicans colonization occurred in mice that received only antibiotics in their drinking water, provided that the mice were housed in the same room as intentionally colonized mice. The fungal strain in unintentionally colonized mice appeared identical to the strain used for intentional GI-tract colonization. This is the first report of horizontal transmission and spontaneous C. albicans colonization in mice. Importantly, many Candida-colonized mice developed serum fungal-specific antibodies. Despite the GI-tract colonization and presence of serum antibodies, the animals made antibodies in response to the Fba immunogen. This mouse model has potential for elucidating C. albicans horizontal transmission and for exploring factors that induce host defense against disseminated candidiasis. Furthermore, a combined protracted GI-tract colonization with Candida and the possibility of serum antibody responses to the presence of the fungus makes this an attractive mouse model for testing the efficacy of vaccines designed to prevent human disseminated candidiasis.
Original article: A simple model for laser drilling

A simple mathematical model of laser drilling is proposed. Assuming axi-symmetry of the process around the axis of the laser beam, a one-dimensional formulation is obtained after cross-sectional averaging. The novelty of the approach relies on the fact that even after dimension reduction, the shape of the hole can still be described. The model is derived, implemented and validated for drilling using lasers with intensities in the GW/cm^2 range and microsecond pulses.
Remotely imaging the plasma sheet with low-altitude satellite clusters

Abstract Low-altitude satellites make latitudinal cuts through the entire plasma sheet within a few minutes. We show that by combining several such satellites it is possible to form an image of a large portion of the plasma sheet within a relatively short time. Strictly speaking such a technique images the field-aligned portion of the plasma sheet, however, theoretical work as well as extensive in situ observations have demonstrated that the plasma sheet is highly isotropic. In practice the most significant limitation is that electron acceleration events (including the auroral bulge) require discarding the associated ion data. An instance when five DMSP satellites (F10–F14) went through the southern hemisphere nightside oval within a 19 min period is used to construct the first partial magnetotail image. The possibilities of combining data from other missions to construct more complete composite images is considered. This technique is also highly useful in statistical studies of the plasma sheet. Because a low-altitude spacecraft cuts through the plasma sheet about 25 times as often as a mid-altitude spacecraft, and hundreds of times more often than high-altitude spacecraft, statistically meaningful surveys of the plasma sheet as a whole are hundreds of times easier using a collection of DMSP satellites. We demonstrate herein that the dawn LLBL flank is an apparent source of cold magnetosheath plasma supplied to the central plasma sheet.
First Evidence that Bone Marrow Cells Contribute to the Construction of Tissue Engineered Vascular Autografts In Vivo

The authors designed and tested a bone marrow cell-seeded biodegradable scaffold to repair cardiac defects that avoids the problems of unwanted adverse effects and lack of growth potential. After being labeled with green fluorescence, bone marrow cells were seeded onto scaffolds and implanted in the inferior vena cava of dogs. After implantation, the grafts were analyzed by using antibodies against endothelial cell lineage markers, endothelium and smooth muscle cells at 3 hours, and then at 2, 4, and 8 weeks. The tissue-engineered vascular autographs caused no obstruction or stenosis. The seeded bone marrow cells expressed endothelial cell lineage markers that were adhered to the scaffold. Proliferation and differentiation followed and resulted in the expression of smooth muscle cell markers and endothelial cell markers, vascular endothelial growth factor and angiopoietin-1. The study results provide evidence that bone marrow cells enable the establishment of tissue-engineered vascular autographs.
Structural basis for germline gene usage of a potent class of antibodies targeting the CD4 binding site of HIV-1 gp120

Background: A large number of anti-HIV-1 antibodies targeting the CD4 binding site (CD4bs) on gp120 have recently been reported. These antibodies, typified by VRC01, are remarkable for both their breadth and potency. Crystal structures have revealed a common mode of binding for several of these antibodies; however, the precise relationship among CD4bs antibodies remains to be defined. Methods: We analyze existing structural and sequence data, propose a set of signature features for potent VRC01-like (PVL) antibodies, and test the importance of these features by mutagenesis. Results: A group of highly potent CD4bs antibodies, previously isolated from 5 different individuals, all derive from the human VH1-2 gene segment and share a set of characteristic residues, including W50, N58, R71, and W100B. Mutagenesis studies on a half-germline version of a VRC01-like antibody confirm that these signature residues are critical for gp120 binding. Neutralization assays with viruses mutated at sites that contact these critical antibody residues also confirm the significance of these interactions. Conclusion: The signature features explain why PVL antibodies derive from a single germ-line human VH gene segment and why certain gp120 sequences are associated with antibody resistance. This analysis also suggests that immunization experiments to elicit VRC01-like antibodies may be problematic in mice or rabbits since they lack germ-line VH genes with all the critical residues. Our results bear on vaccine development and structure-based design to improve the potency and breadth of anti- CD4bs antibodies.
Laban notation, and its application to treating clumsy children.

SUMMARY The Laban method of movement notation has been used for some years to record and analyse body movement of children with various motor disorders. This paper describes the system and discusses its application in the rehabilitation of such children. RESUME Notacion de Laban et son application au traitement des enfants maladroits La methode de Laban de notation du mouvement a ete utilisee depuis quelques annees pour enregistrer et analyser les mouvements corporels d'enfants presentant des troubles moteurs varies. L'article decrit la methode et discute ses applications a la readaptation de tels enfants. ZUSAMMENFASSUNG Die Laban Methode und ihre Anwendung bei der Behandlung unbeholfener Kinder Die Laban Methode ist seit einigen Jahren zur Aufzeichnung und Analysierung von Korperbewegungen bei Kindern mit verschiedenen motorischen Storungen angewandt worden. Diese Arbeit gibt eine Beschreibung der Methode und diskutiert ihre Anwendung bei der Rehabilitation solcher Kinder. RESUMEN Notacion de Laban y su aplicacion en el tratamiento de ninos torpes El metodo de Laban de notacion del movimiento se ha usado durante varios anos para registrar y analizar el movimiento corporal de ninos con diversas alteraciones motoras. La presente comunicacion describe el sistema y discute la aplicacion en la rehabilitacion de tales ninos.
Dust Emission and Molecular Depletion in L1498

The dust continuum emission provides information aboiut the chemical depletion and the properties of cold cores where there is a lack of gas tracers.
Recent trends in Arctic Ocean mass distribution revealed by GRACE

[1] Measurements of ocean bottom pressure by the Gravity Recovery and Climate Experiment (GRACE) and new in situ bottom pressure measurements confirm the accuracy and utility of GRACE measurements in the Arctic Ocean. They reveal a declining trend in bottom pressure that corresponds to mass changes due to decreasing upper ocean salinities near the North Pole and in the Makarov Basin. The spatial distribution and magnitude of these trends suggest the Arctic Ocean is reverting from the cyclonic state characterizing the 1990s to the anticyclonic state that was prevalent prior to the 1990s.
Strategies for the weakest link

(2003). Strategies for The Weakest Link. The American Mathematical Monthly: Vol. 110, No. 4, pp. 330-334.
Determining the toughness of plastically deforming joints

An analysis is presented for the fracture of an adhesively bonded double-cantilever beam that fails with extensive plastic deformation of the adherends. The analysis permits a value for the toughness of the joint to be distinguished from the energy absorbed by the plastic deformation. Specifically, this value for toughness can be determined from post-fracture observations of the deformation and from a knowledge of the constitutive properties of the adherends. The analysis has been used to determine experimentally the toughness of plastically deforming joints formed using three different adhesives to bond a series of different thicknesses of aluminium and steel. In each case, it was found that, despite large differences in the extent of deformation, the value for toughness was dependent only on the materials used to form the joint. The toughness was independent of the thickness of the adherends.
Comparison of cell-based and cell-free protocols for producing target proteins from the Arabidopsis thaliana genome for structural studies.

We describe a comparative study of protein production from 96 Arabidopsis thaliana open reading frames (ORFs) by cell-based and cell-free protocols. Each target was carried through four pipeline protocols used by the Center for Eukaryotic Structural Genomics (CESG), one for the production of unlabeled protein to be used in crystallization trials and three for the production of 1 5 N-labeled proteins to be analyzed by 1 H- 1 5 N NMR correlation spectroscopy. Two of the protocols involved Escherichia coli cell-based and two involved wheat germ cell-free technology. The progress of each target through each of the protocols was followed with all failures and successes noted. Failures were of the following types: ORF not cloned, protein not expressed, low protein yield, no cleavage of fusion protein, insoluble protein, protein not purified, NMR sample too dilute. Those targets that reached the goal of analysis by 1 H- 1 5 N NMR correlation spectroscopy were scored as HSQC + (protein folded and suitable for NMR structural analysis), HSQC′ (protein partially disordered or not in a single stable conformational state), HSQC- (protein unfolded, misfolded, or aggregated and thus unsuitable for NMR structural analysis). Targets were also scored as X- for failing to crystallize and X+ for successful crystallization. The results constitute a rich database for understanding differences between targets and protocols. In general, the wheat germ cell-free platform offers the advantage of greater genome coverage for NMR-based structural proteomics whereas the E. coli platform when successful yields more protein, as currently needed for crystallization trials for X-ray structure determination.
Path Selection and Rate Allocation for Video Streaming in Multihop Wireless Networks

In this paper, we investigate the important problem of optimal path selection and rate allocation for concurrent video sessions in a multihop wireless network. We present a novel formulation of the problem, which optimizes the application level performance such as video distortion, while seamlessly incorporating the network layer parameters such as packet delay and loss. For the formulated problem, we propose a branch-and-bound framework, predicated on the powerful reformulation-linearization technique, that can produce (1-epsi) optimal solutions. We demonstrate through analytical and simulation results that the proposed mechanism can fully utilize the network capacity and improve the quality of reconstructed video. The proposed approach provides an important methodology for addressing non-convex, non-polynomial programming problems that arise in wireless networks, especially those involving cross-layer design and optimizations
Stochastic Decomposition: An Algorithm for Two-Stage Linear Programs with Recourse

We present a cutting plane algorithm for two-stage stochastic linear programs with recourse. Motivated by Benders' decomposition, our method uses randomly generated observations of random variables to construct statistical estimates of supports of the objective function. In general, the resulting piecewise linear approximations do not agree with the objective function in finite time. However, certain subsequences of the estimated supports are shown to accumulate at supports of the objective function, with probability one. From this, we establish the convergence of the algorithm under relatively mild assumptions.
Pulmonary scintigraphy in pediatrics

Pulmonary radionuclide studies in children provide reliable information on regional lung perfusion and ventilation. They are easily and safely performed and they do not usually require full patient cooperation. Their clinical indications and applications are not as well defined as and frequently differ from those in pulmonary disorders of the adult patient. Radiation exposures resulting from radionuclide pulmonary examinations are well within acceptable limits set up for a variety of radiologic diagnostic procedures. Our lung scanning experience with a spectrum of congenital and acquired cardiopulmonary diseases is presented and the contribution of the radionuclide methods to the specific problems facing the pediatrician or the surgeon is discussed.
The in vitro motility of human gliomas increases with increasing grade of malignancy

Background. Malignant gliomas are a highly invasive disease with a dismal prognosis despite aggressive therapeutic interventions. Methods. The authors tested the hypothesis that increasing in vitro motility of human glial tumors correlates with increasing grade of malignancy. A radial dish assay was used to quantitatively assess the brain tumor cell motility of 14 low passage cell lines derived from human glial tumors of varied malignancy, and 3 cell lines derived from human glia. The egress of cells from a central region of high tumor cell density to a region of lower tumor cell density was determined at various time points. A motility coefficient (MC), the slope of distance traveled against time, was generated by simple linear regression analysis. Results. The MC increased with the increased histologic grade of malignancy. Generation of a t-statistic was used to determine the significance of differences in motility among 5 histopathologic groups: 10 glioblastoma (World Health Organization Grade IV) cell lines (mean MC, 0.00396), 2 mixed anaplastic oligoastrocytoma (Grade III) cell lines (mean MC, 0.00382), 1 anaplastic astrocytoma (Grade III) cell line (mean MC, 0.00295), 1 Grade I glioma cell line (mean MC, 0.00206), and 3 human glial cell lines (mean MC, 0.00110). Conclusions. The radial dish assay provided a reproducible method for quantitatively assessing brain tumor cell motility. The higher MC observed with the malignant human glioma cell lines correlated with the tendency of these tumors to invade into adjacent brain tissue. The potential to inhibit glial tumor motility may provide an important therapeutic avenue in the future. Cancer 1995;75:2904–9.
Synthesis and identification of small molecules that potently induce apoptosis in melanoma cells through G1 cell cycle arrest.

Late-stage malignant melanoma is a cancer that is refractory to current chemotherapeutic treatments. The average survival time for patients with such a diagnosis is 6 months. In general, the vast majority of anticancer drugs operate through induction of cell cycle arrest and cell death in either the DNA synthesis (S) or mitosis (M) phase of the cell cycle. Unfortunately, the same mechanisms that melanocytes possess to protect cells from DNA damage often confer resistance to drugs that derive their toxicity from S or M phase arrest. Described herein is the synthesis of a combinatorial library of potential proapoptotic agents and the subsequent identification of a class of small molecules (triphenylmethylamides, TPMAs) that arrest the growth of melanoma cells in the G1 phase of the cell cycle. Several of these TPMAs are quite potent inducers of apoptotic death in melanoma cell lines (IC50 ∼ 0.5 μM), and importantly, some TPMAs are comparatively nontoxic to normal cells isolated from the bone marrow of healt...
Termination of reproductive diapause in the Sitka spruce weevil, Pissodes strobi (Peck) (Col., Curculionidae) in western Washington

Laboratory tests were conducted to determine the role of cold temperature conditioning and host material on termination of reproductive diapause of female Pissodes strobi. Females exposed to temperatures of 4.4°C, 10°C, 15.5°C and 21.1 °C for periods of 20, 40 and 60 days did not break diapause. However, females fed on Sitka spruce (Picea sitchensis) terminals under long days matured their ovaries; females on lateral branches continued to have undeveloped ovaries. Males did not show evidence of reproductive diapause. Zusammenfassung Untersuchungen zur Beendigung der Reproduktionsdiapause bei Pissodes strobi (Peck) (Col., Curculionidae) In Laborversuchen wurde gezeigt, welche Bedeutung niedrige Temperaturen und das Wirtsmaterial fur die Beendigung der Reproduktionsdiapause der Weibchen von P. strobi haben. Bei Weibchen, die Temperaturen von 4,4 °C, 10 °C, 15,5 °C und 21,1 °C fur 20, 40 oder 60 Tage ausgesetzt waren, konnte die Diapause nicht gebrochen werden. Jedoch hatten Weibchen, die unter Kurztagbedingungen am Terminaltrieb der Sitkafichte (Picea sitchensis) frasen, reife Ovarien; bei Weibchen, die an den Seitentrieben gefressen hatten, waren die Ovarien noch nicht reif. Bei den Mannchen konnte keine Reproduktionsdiapause festgestellt werden.
Anticipated mortality HIV vulnerability and psychological distress among adolescents and young adults at higher and lower risk for HIV infection.

This study described multivariate patterns of associations among psychological distress, anticipated mortality, and perceived vulnerability to HIV among urban, multiethnic samples of (a) adolescents (N = 120) undergoing substance abuse treatment, and (b) young adult university students (N = 222). While there were significant correlations between (a) psychological distress and reported vulnerability to HIV in the treatment sample; and (b) psychological distress and anticipated mortality in the university sample, there was no significant relation between anticipated mortality and perceived vulnerability to HIV in either sample. Cluster analysis revealed four distinct and meaningful groups in both samples, including parallel high- and low-functioning subgroups. Multivariate group differences in both samples were validated via corresponding group differences in (a) motives for drinking during sex, and (b) markers of serious psychological distress (e.g., suicidal thoughts and attempts). The findings challenge popular sterotpes of adolescents' perceptions of their own mortality and vulnerability to HIV and may have significant implications for the planning and implementation of effective HIV preventions among at-risk youth.
Histone acetyltransferase Rtt109 is required for Candida albicans pathogenesis

Candida albicans is a ubiquitous opportunistic pathogen that is the most prevalent cause of hospital-acquired fungal infections. In mammalian hosts, C. albicans is engulfed by phagocytes that attack the pathogen with DNA-damaging reactive oxygen species (ROS). Acetylation of histone H3 lysine 56 (H3K56) by the fungal-specific histone acetyltransferase Rtt109 is important for yeast model organisms to survive DNA damage and maintain genome integrity. To assess the importance of Rtt109 for C. albicans pathogenicity, we deleted the predicted homolog of Rtt109 in the clinical C. albicans isolate, SC5314. C. albicans rtt109−/− mutant cells lack acetylated H3K56 (H3K56ac) and are hypersensitive to genotoxic agents. Additionally, rtt109−/− mutant cells constitutively display increased H2A S129 phosphorylation and elevated DNA repair gene expression, consistent with endogenous DNA damage. Importantly, C. albicans rtt109−/− cells are significantly less pathogenic in mice and more susceptible to killing by macrophages in vitro than are wild-type cells. Via pharmacological inhibition of the host NADPH oxidase enzyme, we show that the increased sensitivity of rtt109−/− cells to macrophages depends on the host’s ability to generate ROS, providing a mechanistic link between the drug sensitivity, gene expression, and pathogenesis phenotypes. We conclude that Rtt109 is particularly important for fungal pathogenicity, suggesting a unique target for therapeutic antifungal compounds.
Changes in pulsatile release of neuropeptide-Y and luteinizing hormone (LH)-releasing hormone during the progesterone-induced LH surge in rhesus monkeys

In previous studies we have shown that the pulsatility of LH-releasing hormone (LHRH) release in gonadectomized monkeys is modulated by input from neuropeptide-Y (NPY) neurons: 1) the endogenous release of NPY in the stalk-median eminence (S-ME) was pulsatile; 2) NPY pulses were temporally correlated with LHRH pulses, with NPY pulses preceding LHRH pulses by approximately 5 min; and 3) infusion of NPY into the S-ME stimulated LHRH release, whereas 4) infusion of antiserum to NPY suppressed endogenous LHRH pulses. It is not known, however, whether ovarian steroid hormones alter the pulsatility of NPY and LHRH release or whether the temporal correlation of NPY and LHRH pulses is maintained during the LH surge. In the present study we examined the changes in pulsatile release of NPY and LHRH in ovariectomized monkeys treated with estradiol benzoate (EB) followed by progesterone or oil. Using push-pull perfusion, perfusate samples from S-ME were collected at 10-min intervals for 15 h. NPY and LHRH concentrations in the perfusates were measured by RIA. Circulating LH levels were also monitored by periodic blood sampling and RIA. Injection of progesterone (sc) after EB induced an LH surge with a peak latency of 7.3 +/- 1.3 h (mean +/- SE) in seven of seven monkeys, whereas oil injection after EB elicited an LH surge in none of seven monkeys. The progesterone-induced LH surge was associated with an increase in LHRH release; the mean, pulse amplitude, and pulse frequency increased significantly (for all, P < 0.05) 4-8 h after progesterone. NPY pulse frequency also increased significantly (P < 0.05) 4-8 h after progesterone treatment, whereas mean release and pulse amplitude did not change in response to progesterone. Oil treatment after EB administration did not alter any parameter of LHRH and NPY pulses. Interestingly, the NPY and LHRH pulses were highly correlated (P < 0.001) in monkeys treated with either EB-progesterone or EB-oil, and NPY pulses preceded LHRH pulses by 4.8 +/- 0.7 and 5.1 +/- 0.6 min, respectively. In summary, 1) an episode of increased LHRH release occurs before and during the progesterone-induced LH surge; 2) acceleration of LHRH pulse frequency and the increase in LHRH pulse amplitude after progesterone are accompanied by acceleration of NPY pulse frequency; and 3) ovarian steroids do not affect the temporal correlation between NPY and LHRH pulses.(ABSTRACT TRUNCATED AT 400 WORDS)
Evolution of plant defense mechanisms. Relationships of phenylcoumaran benzylic ether reductases to pinoresinol-lariciresinol and isoflavone reductases.

Abstract Pinoresinol-lariciresinol and isoflavone reductase classes are phylogenetically related, as is a third, the so-called “isoflavone reductase homologs.” This study establishes the first known catalytic function for the latter, as being able to engender the NADPH-dependent reduction of phenylcoumaran benzylic ethers. Accordingly, all three reductase classes are involved in the biosynthesis of important and related phenylpropanoid-derived plant defense compounds. In this investigation, the phenylcoumaran benzylic ether reductase from the gymnosperm, Pinus taeda, was cloned, with the recombinant protein heterologously expressed inEscherichia coli. The purified enzyme reduces the benzylic ether functionalities of both dehydrodiconiferyl alcohol and dihydrodehydrodiconiferyl alcohol, with a higher affinity for the former, as measured by apparent K m andV max values and observed kinetic3H-isotope effects. It abstracts the 4R-hydride of the required NADPH cofactor in a manner analogous to that of the pinoresinol-lariciresinol reductases and isoflavone reductases. A similar catalytic function was observed for the corresponding recombinant reductase whose gene was cloned from the angiosperm,Populus trichocarpa. Interestingly, both pinoresinol-lariciresinol reductases and isoflavone reductases catalyze enantiospecific conversions, whereas the phenylcoumaran benzylic ether reductase only shows regiospecific discrimination. A possible evolutionary relationship among the three reductase classes is proposed, based on the supposition that phenylcoumaran benzylic ether reductases represent the progenitors of pinoresinol-lariciresinol and isoflavone reductases.
Normative Conflicts and The Logic of ‘Ought’

On the face of it, normative conflicts are commonplace. Yet standard deontic logic declares them to be logically impossible. That prompts the question, What are the proper principles of normative reasoning if such conflicts are possible? This paper examines several alternatives that have been proposed for a logic of ‘ought’ that can accommodate normative conflicts, and finds all of them unsatisfactory as measured against three criteria of adequacy. It then introduces a new logic that does meet all three criteria, and so allows for the possibility of genuine normative conflicts.
Cumulus Convection in Shear Flow—Three-Dimensional Numerical Experiments

Abstract A three-dimensional model of deep, moist convection is described. The model is fully compressible and utilizes a “time-splitting” method of integration in order to make the model economically feasible. This study represents an extension of the numerical experiments reported by Cotton (1975). In that work the profiles of the ratio of average cloud water content to the moist-adiabatic water content (Qc/QA) predicted by a one-dimensional Lagrangian (1DL) and a one-dimensional time-dependent (1DTD) model are compared with case study observed data and the average Qc/QA profiles reported by Warner (1970a). In this work, data predicted by a three-dimensional (3D) cloud simulation in a stagnant environment and a 3D cloud simulation in the observed shear flow are compared with observed data and the earlier model calculations. The results of this study demonstrated that all the cloud simulations in an initially stagnant environment, including the 1DL, 1DTD and 3D models, predicted profiles of Qc/QA whic...
Germline gain-of-function mutations in SOS1 cause Noonan syndrome

Noonan syndrome, the most common single-gene cause of congenital heart disease, is characterized by short stature, characteristic facies, learning problems and leukemia predisposition. Gain-of-function mutations in PTPN11, encoding the tyrosine phosphatase SHP2, cause approximately 50% of Noonan syndrome cases. SHP2 is required for RAS-ERK MAP kinase (MAPK) cascade activation, and Noonan syndrome mutants enhance ERK activation ex vivo and in mice. KRAS mutations account for <5% of cases of Noonan syndrome, but the gene(s) responsible for the remainder are unknown. We identified missense mutations in SOS1, which encodes an essential RAS guanine nucleotide-exchange factor (RAS-GEF), in approximately 20% of cases of Noonan syndrome without PTPN11 mutation. The prevalence of specific cardiac defects differs in SOS1 mutation-associated Noonan syndrome. Noonan syndrome-associated SOS1 mutations are hypermorphs encoding products that enhance RAS and ERK activation. Our results identify SOS1 mutants as a major cause of Noonan syndrome, representing the first example of activating GEF mutations associated with human disease and providing new insights into RAS-GEF regulation.
Reduction of Cr(edta)(OH)2− at mercury electrodes as controlled by the rate of its protonation

Abstract Sampled dc and normal pulse polarography were employed to measure the kinetics of the chemical reaction that precedes the reduction of Cr(edta)(OH)2− to Cr(edta)OH2−2 at mercury electrodes. The chemical reaction was identified as the protonation of the complex by protons and acidic components of buffers. The requirement that protonation precede reduction is argued to result from the lower activation energy involved in elongating a chromium—water compared with a chromium—hydroxide bond.
Shape and Albedo Variations of Asteroid 15 Eunomia

447measurements are usually hemisphere- and time-inte- lightcurve instances. Observations done at different aspectgrated with no provision made to measure projected angles give data for different observed sub-Earth latitudesarea variations and albedo variations over a rotation. of the asteroid thus slightly different hemispheres of theUsing a technique in which reﬂected and emitted ﬂux asteroid with possibly differing surface properties areare concurrently measured for a target asteroid in order viewed.to match accurately rotational phases, relative changes The use of time-resolved reﬂected and emittedin projected area and albedo may be calculated in order lightcurveswouldallowinvestigationofhowprojectedareato deduce variations in asteroid shape, albedo, and surface and albedo change over a rotation period for an asteroid.thermal properties. Albedo and possibly color variations would be detectableThe research reported here takes the simultaneously as well as gross topographic features which would changemeasured reﬂected near-infrared lightcurve and emitted the projected area in a unique and identiﬁable manner.thermal lightcurve and uses the standard, nonrotating, Since the general shape of an asteroid is unknown to startspherical thermal model, not to calculate absolute values with, the initial assumption is made that the object underfor projected area (and thus diameters) and albedo, but study is spherical in order to use the generally acceptedto ﬁnd relative changes in these values over a rotational thermal model to calculate total thermal output. The mea-period. This is a quantitative extension of the combined surement of visible and thermal ﬂux under good conditionsvisible and thermal infrared (V/TIR) lightcurve technique canbequiteprecise.Largesystematicerrorscanarisewhen(Lebofsky and Rieke 1979, Hartmann and Cruikshank applying an imperfect thermal model in ﬁnding absolute1980, Lebofsky
Effect of para-aminohippurate on renal transport of oxalate.

Effect of para-aminohippurate on renal transport of oxalate. Infusion of para-aminohippurate (PAH) at rates below the maximum rate of transport (T m ) of PAH in the rat resulted in a significant decrease in the fractional excretion of oxalate (FE Ox ) from 128.1% to 113.9% (P Ox ) to the early proximal tubule, however, was unchanged from control values, whereas FD Ox to the late proximal tubule was significantly decreased from 126.4% to 107.4% (P m of PAH resulted in a decrease in FD Ox to the early proximal tubule to 105.3% and to the late proximal tubule to 105.5%, and in FE Ox to 100.5%. These changes were not the result of alterations in urinary sodium or bicarbonate excretion. Microinjection studies indicated that PAH did not affect the tubular absorption of oxalate. These studies suggest that PAH inhibits the tubular secretion of oxalate and that there may be more than one secretory system for oxalate with differing affinities for oxalate and PAH in the early and late proximal tubules. Effet du para-aminohippurate sur le transport renal de l'oxalate. La perfusion de para-aminohippurate (PAH) a des debits inferieurs au T m PAH chez le rat a pour consequence une diminution significative de l' excretion fractionnelle de l'oxalate (FE Ox ) de 128,1% a 113,9% (P Ox , au tube contourne proximal precoce, n'est cependant pas differente des valeurs controles alors que FD Ox au tube proximal tardif diminue significativement de 126,4% a 107,4% (P Ox au tube proximal precoce a 105,3%, a 105,5% au tube proximal tardif, et a 100,5% pour FE Ox . Ces modifications ne sont pas les consequences de modifications de l'excretion urinaire de bicarbonate ou de sodium. Des microinjections montrent que le PAH ne modifie pas la reabsorption de l'oxalate. Ces etudes suggerent que le PAH inhibe la secretion tubulaire de l'oxalate et qu'ilpourrait y avoir plud d'un systeme de secretion pour l'oxalate avec des affinites differentes pour l'oxalate et le PAH dans le tube proximal precoce et tardif.
When Words Speak Louder than Actions: Environmental Problem Solving in the Classroom

Abstract Learning by doing may not be the most effective strategy for teaching environmental problem-solving skills. A survey of Michigan educators indicates that of the teaching strategies listed, case studies and talking about what others do to solve environmental problems are the most important. The implications of building familiarity with environmental issues and solutions from a variety of examples are discussed, and an explanation for the reported low success of classroom action projects is presented.
Non-Franck-Condon transitions in two-electron capture from D2 by low-energy, highly charged Ar projectiles.

The process of two-electron capture has been studied for the collision systems Ar/sup +5/+D/sub 2/ at 500 and 1000 eV (v = 0.022 and 0.032 a.u.). The total laboratory energies of the deuterons emitted in the Coulomb explosion of the target following double capture were measured in coincidence with the charge-changed projectiles detected at selected scattering angles. Using a computer simulation of the kinematics of these reactions, we were able to deduce the effective two-electron binding energies for D/sub 2/ as a function of collision energy. The results indicate that at these low energies the Franck-Condon principle is not applicable.
Normal mode calculation of a netropsin-DNA complex: effect of structural deformation on vibrational spectrum.

Calculations of the normal mode spectrum of a netropsin-DNA complex, an isolated DNA helix of the same sequence, and a free netropsin molecule were carried out and compared with observations. We find that the frequency of modes of the complex that are primarily vibrations localized to the helix are relatively unchanged from the frequencies found for similar modes of the isolated helix. On the other hand, the frequencies of those modes of the complex that are found to be primarily in the netropsin are found to change significantly in the complex from that of the free netropsin. Further analysis indicates that the changes in the “netropsin modes” are primarily due to the conformational deformation induced in the netropsin by formation of the complex. All the frequencies and shifts in frequency are in good agreement with recent Raman measurements. © 1995 John Wiley & Sons, Inc.
Application of the superarmed glycosyl donor to chemoselective oligosaccharide synthesis.

Recently, we discovered a novel method for “superarming” glycosyl donors. Herein, this concept has been exemplified in one-pot oligosaccharide syntheses, whereby the superarmed glycosyl donor was chemoselectively activated over traditional “armed” and disarmed glycosyl acceptors. Direct side-by-side comparison of the reactivities of the classic armed and superarmed glycosyl donors further validates the credibility of the novel concept.