cssi/SciSciGPT-SciSciNet huggingface dataset:
Blood DNA methylation profiles improve breast cancer prediction

Although blood DNA methylation (DNAm) profiles are reported to be associated with breast cancer incidence, they have not been widely used in breast cancer risk assessment. Among a breast cancer case-cohort of 2,774 women (1,551 cases) in the Sister Study, we used candidate CpGs and DNAm estimators of physiologic characteristics to derive a methylation-based breast cancer risk score, mBCRS. Overall, 19 CpGs and five DNAm estimators were selected using elastic net regularization to comprise mBCRS. In a test-set, higher mBCRS was positively associated with breast cancer incidence, showing similar strength to the polygenic risk score (PRS) based on 313 single-nucleotide polymorphisms (313-SNP). Area under the curve (AUC) for breast cancer prediction was 0.60 for self-reported risk factors (RFs), 0.63 for PRS and 0.63 for mBCRS. Adding mBCRS to PRS and RFs improved breast cancer prediction from 0.66 to 0.71. mBCRS findings were replicated in a nested case-control study within the EPIC-Italy cohort. These results suggest that mBCRS, a risk score derived using blood DNAm, can be used to enhance breast cancer prediction.
Accountability and cyber conflict: examining institutional constraints on the use of cyber proxies:

As state-sponsored cyber operations have proliferated, some states are outsourcing these operations to non-state cyber proxies. However, given the relative ease of outsourcing cyber operations, it ...
Theories of Delinquency Intervention and Treatment Research Strategies

This chapter discusses how the Adolescent Diversion Project attempted to bridge the gap between delinquency intervention theories and treatment research methods. Thus it introduces both the intervention theories and the research methods used by the project. Because of the complexity of the issues we tried to address, two distinct research strategies were utilized—both experimental and correlational. Therefore, the questions that each strategy attempted to address will be described here as well.
Passive Mechanical Skin Stretch for Multiple Degree-of-Freedom Proprioception in a Hand Prosthesis

In this paper, we present a passive linear skin stretch device that can provide proprioceptive feedback for multiple degrees of freedom (DOF) in a prosthetic hand. In a 1-DOF virtual targeting task, subjects performed as well with our device as with a vibrotactile array, and significantly better (\(p<0.05\)) than having no feedback at all. In a 3-DOF grip recognition task, subjects were able to classify six different grips with 88.0 % accuracy. Training took 6 min and the average time to classification was 5.2 s. Subjects were also able to match a set of target grip apertures with 11.1 % error on average.
The Src family tyrosine kinase, fyn, is a negative regulator of inflammation-induced apoptosis in the lung (1176.6)

Endothelial cell apoptosis is an early event in the development of acute respiratory distress syndrome (ARDS). We hypothesized that the Src-family tyrosine kinases (STK) would differentially regulate endothelial cell apoptosis. Human pulmonary microvascular endothelial cells (hPMVEC) were transfected with siRNA against fyn or yes and then treated with cytomix (LPS, TNF-α, IL-1β and INF-γ) or vehicle. Following cytomix treatment knock-down of fyn resulted in greater levels of caspase 3 activity and lower viable cell numbers, while knock-down of yes resulted in lower levels of caspase 3 activity and greater viable cell numbers, than in scramble treated control hPMVEC. We then tested the hypothesis that mice deficient in fyn will have greater lung injury following exposure to LPS. Wild-type and fyn-/- mice were given LPS 10 mg/kg or saline before harvesting tissues or measuring static lung compliance. The fyn-/- mice had lower static lung compliance 24 hours after LPS compared to the WT mice. LPS exposure al...
An internet multicast symposium concerning the microcirculation of the islets of langerhans

Abstract The Internet Globally-linked Computer System was used to conduct an international scientific symposium. The symposium was held at the VAMC-Long Beach and consisted of prepared lectures that were multicast over the Internet. The basic unit of hardware used for the Internet Multicast was the Silicon Graphics Indy Unix Workstation, which was equipped with a color video camera. The multicast required four additional pieces of software from the file transfer protocol. The multicast backbone protocol allowed for simultaneous audio and video signals (the presenter, the slides, and the videotape images of islet microcirculation studies) to be transmitted over the computer network. The faculty included 12 experts in microcirculation, who gave 15-min lectures that included a question and answer period. All lectures were received at 14 computer stations in six countries. Eleven of the faculty gave their lectures at the VAMC-Long Beach, and one gave her lecture at the Massachusetts Institute of Technology in Boston, MA. The presenter from Boston was able to receive and answer questions from the faculty at the VAMC-Long Beach. An estimated $12,000 was saved in travel, hotel, and food costs and an estimated 180 travel hours were saved by viewers who did not have to travel to the symposium. We have demonstrated that a scientific symposium can be conducted using the Internet. We propose that many of our future meetings will be organized over the computer network. This format of multiimage projections allows us to effectively communicate in a personal way with a reduction in expensive and time-consuming travel.
Are there easy-to-check necessary and sufficient conditions for straightforward interval computations to be exact?

We prove that no “efficient” (easy-to-check) necessary and sufficient conditions are possible for checking whether straightforward interval computations lead to the exact result.
The sources of forecast errors

Abstract In Muth's original theory, the passage of time is the only source of forecast error. Persistent rejections led Muth to surmise problems in the data also cause forecast error; Keane and Runkle argue that many rejections of Muth's theory are reversed if data problems are properly considered. Experimental evidence allows a particularly clean test because the data are inherently simpler. The continued rejection of Muth's hypothesis suggests model uncertainty as a source of forecast error.
Disabling Asterixis Induced By Gabapentin

We describe a case of an 80-year-old woman who developed disabling asterixis after taking gabapentin for post-herpetic neuropathy. She had end-stage renal disease necessitating intermittent hemodialysis for the previous 5 years. She had begun taking gabapentin about 1 week prior to being admitted to the hospital, and a family member observed a new tremor developing about 3 days prior to hospital admission. Neurologic examination revealed diffuse axial and appendicular negative myoclonus. Because of her renal dysfunction, the gabapentin dose was empirically reduced from 300 mg by mouth three times daily to 100 mg three times daily. Gabapentin was discontinued on hospital day 5 because of concerns for drug toxicity causing the abnormal movements. Two days after gabapentin was discontinued, she has complete resolution of her negative myoclonus. J Med Cases. 2015;6(7):285-286 doi: http://dx.doi.org/10.14740/jmc2143w
Carotid intima-media thickness measurements are not affected by the ultrasound frequency.

Objective: Carotid intima-media thickness (IMT) is a B-mode ultrasound measure of subclinical atherosclerosis predictive of future cardiovascular risk. Carotid IMT measurements were historically obtained at an ultrasound frequency of 8 MHz or lower, but it is unknown whether measurements obtained at higher frequencies using newer, more advanced ultrasound technology allow for valid comparison to the older general population databases that are commonly used for the interpretation of carotid IMT results. Methods: Carotid IMT studies were conducted in 35 consecutive patients at standard (8 MHz) and high (14 MHz) frequencies and measurements were performed by two independent expert readers. Systematic bias was assessed by using the paired t-test and agreement was analyzed with the Bland–Altman method. Results: The sample mean carotid IMT obtained at 14 MHz was 0.006 mm lower than that obtained at 8 MHz. The 95% confidence interval (CI) for the mean difference between frequencies indicated that the population mean for 14 MHz is unlikely to be more than 0.02 mm lower than for 8 MHz (95% CI –0.017 to 0.004). The 95% reference range for the difference between the two transducer frequencies indicated that the thickness obtained at 14 MHz was within 0.05 mm of that obtained at 8 MHz for 95% of subjects. Conclusions: Carotid IMT measurements obtained at higher transducer frequencies are similar to those obtained at standard frequency. This finding has important clinical implications because it validates comparison of carotid IMT measurements obtained with newer, more advanced ultrasound technology with the landmark reference carotid IMT studies commonly used for interpretation of carotid IMT results. (Echocardiography 2012;29:354-357)
Solid‐phase extraction of primary aromatic amines from aqueous samples; comparison with liquid‐liquid extraction techniques

Abstract The extraction of the following primary aromatic amines from aqueous samples was studied: 1,4‐phenylenediamine, 2,4‐diaminotoluene, benzidine, 4,4'‐methylenebis (2‐chloroaniline), 3,3'‐dimethylbenzidine, and 3,3'‐dichlorobeiizidine. Five different adsorbents were evaluated for solid‐phase extraction (SPE) in the reversed‐phase mode. An SPE method utilizing a styrene/divinylbenzene copolymer disk was developed, and compared to separatory funnel and continuous liquid‐liquid extraction techniques. Significantly better recoveries were obtained on fortified tap, stream, and lake water samples using SPE.
The effect of site and technique of splenic tissue reimplantation on pneumococcal clearance from the blood

The technique and site of reimplantation of splenic tissue influences survival of laboratory animals following intravenous injection of pneumococci. Splenic tissue was prepared by slicing, mincing, or grating the spleen. The tissue was placed subcutaneously, intraperitoneally, retroperitoneally, or in an omental pouch. This study was designed to determine the rate of pneumococcal clearance from the blood stream 16 weeks following splenic reimplantation by four different methods. All animals were challenged with an intravenous 1 mL bolus containing 10 7 bacteria. The New Zealand white rabbits were divided into six groups: (1) intact spleen; (2) splenectomized; (3) spleen slices in an omental pouch; (4) minced spleen in an omental pouch; (5) splenic tissue implanted subcutaneously; and (6) bits of spleen dropped into the peritoneal cavity. Animals with an intact spleen and those with spleen slices implanted into an omental pouch cleared bacteria during the first hour and all bacteria had disappeared at three hours. Bacteremia persisted longer than three hours in the other groups. Splenic tissue had regenerated in all animals with omental pouch implants, in four of six with minced spleen dropped into the peritoneal cavity but in only one with a subcutaneous implant. Reimplanted splenic tissue clears pneumococci from the blood stream best when thin slices of spleen are placed in an omental pouch. This technique also assures successful regeneration of splenic tissue.
Alkaline phosphatase activity in leukocytes of dogs and cats

Alkaline phosphatase activity was not found in mature neutrophils in the peripheral blood of healthy dogs and cats. Negative results were obtained using four different technics; after staining smears at different incubation temperatures, times and pH; after incubation of smears in substrate solutions containing known activators of the enzyme; after the cell membrane permeability was altered; and after administration of corticotrophin, prednisolone and progesterone. In contrast, alkaline phosphatase activity was demonstrated in some eosinophils of both species. The proportion of ALP-positive eosinophils and the degree of enzyme activity varied with animals in each species. The enzyme activity in eosinophils generally increased with increase in the incubation temperature, time, and pH. The anticoagulant used did not significantly influence the enzyme activity. Administration of different hormones and addition of various activators to the incubation medium had variable effects on eosinophilic alkaline phosphatase activity. A small number of ALP-positive immature leukocytes were seen in the bone marrow of dogs and cats. On the basis of granule size, most of these cells were considered to belong to either the eosinophil series or the neutrophil series.
A Neuro-ForecastWater-Filling Scheme of Server Scheduling

Dynamic server scheduling schemes in queuing systems accommodating delay-sensitive traffic need to address the tradeoff between efficiency and fairness. For delay-sensitive traffic, threshold-exceeding delay or equivalently loss is used as a measure of efficiency. In this paper, a pair of dynamic server scheduling schemes for queuing systems accommodating delaysensitive traffic are compared. Each scheme consists of two components. The first component attempts at forecasting the arriving traffic patterns of the sources sharing the server bandwidth and the second component makes the assignment of server bandwidth among the sources. The schemes utilize BFGS and resilient backpropagation learning in perceptron neural networks to forecast the arriving traffic patterns, respectively. Once the traffic patterns are forecast, the schemes rely on water-filling to make the server bandwidth assignments max-min fair. Our simulations reveal the efficiency and fairness characteristics of the schemes.
Structural and functional properties of human and mouse apolipoprotein A-I

Abstract Mouse and human plasma apolipoprotein A-I (apo A-Im and apo A-Ih, respectively) were investigated to compare their molecular properties in solution, their incorporation into palmitoyloleoylphosphatidylcholine-apo A-I (POPC-apo A-I) discoidal complexes, their structural stability in discoidal complexes and high-density lipoproteins (HDL), and their effect on structural rearrangement of discoidal complexes upon interaction with low-density lipoproteins (LDL). Unlike apo A-Ih, only minimal concentration-dependent self-association was observed for apo A-Im. While both apo A-Im and apo A-Ih formed discoidal complexes of distinct composition and size that reflected reassembly molar ratios of POPC/apo A-I, apo A-Im demonstrated specific deficiencies in formation of larger-sized complexes. Denaturation of both apo A-Im- or apo A-Ih-containing complexes and HDL with guanidine hydrochloride (GuHCl) indicated significantly reduced stabilization of apo A-Im by lipid in these particles. Interaction of apo A-Im- or apo A-Ih-containing discoidal complexes with human plasma LDL revealed a more extensive conversion of apo A-Im-complexes to smaller species. Mean hydrophobicities and mean hydrophobic moments of amphipathic helical segments in apo A-Im and apo A-Ih were compared; differences potentially contributing to differential lipid-binding properties between apo A-Im and apo A-Ih were identified. Our results demonstrate differences between apo A-Im and apo A-Ih that may contribute to the major changes in plasma HDL distribution and function observed in apo A-Ih transgenic mice.
Microglial Phagocytosis Induced by Fibrillar β-Amyloid and IgGs Are Differentially Regulated by Proinflammatory Cytokines

Microglia undergo a phenotypic activation in response to fibrillar beta-amyloid (fAbeta) deposition in the brains of Alzheimer's disease (AD) patients, resulting in their elaboration of inflammatory molecules. Despite the presence of abundant plaque-associated microglia in the brains of AD patients and in animal models of the disease, microglia fail to efficiently clear fAbeta deposits. However, they can be induced to do so during Abeta vaccination therapy attributable to anti-Abeta antibody stimulation of IgG receptor (FcR)-mediated phagocytic clearance of Abeta plaques. We report that proinflammatory cytokines attenuate microglial phagocytosis stimulated by fAbeta or complement receptor 3 and argue that this may, in part, underlie the accumulation of fAbeta-containing plaques within the AD brain. The proinflammatory suppression of fAbeta-elicited phagocytosis is dependent on nuclear factor kappaB activation. Significantly, the proinflammatory cytokines do not inhibit phagocytosis elicited by antibody-mediated activation of FcR, which may contribute to the efficiency of Abeta vaccination-based therapy. Importantly, the proinflammatory suppression of fAbeta phagocytosis can be relieved by the coincubation with anti-inflammatory cytokines, cyclooxygenase inhibitors, ibuprofen, or an E prostanoid receptor antagonist, suggesting that proinflammatory cytokines induce the production of prostaglandins, leading to an E prostanoid receptor-dependent inhibition of phagocytosis. These findings support anti-inflammatory therapies for the treatment of AD.
Anthropologie ; l'écriture et Lacan

L’auteur s’interroge sur la facon dont les diverses modalites d’invention de l’ecriture reamenagent les liens et les oppositions entre signifiant et signifie. Il examine alors les liens entre les theories de Levi-Strauss et celles de Lacan, tout en plaidant pour une anthropologie soucieuse de l’histoire.
A Community Mental Health Implementation of Parent-Child Interaction Therapy (PCIT)

Parent-Child Interaction Therapy (PCIT) has been identified as an evidence-based practice in the treatment of externalizing behavior among preschool-aged youth. Although considerable research has established its efficacy, little is known about the effectiveness of PCIT when delivered in a community mental health setting with underserved youth. The current pilot study investigated an implementation of PCIT with primarily low-socioeconomic status, urban, ethnic minority youth and families. The families of 14 clinically referred children aged 2-7 years and demonstrating externalizing behavior completed PCIT initial assessment, and 12 began treatment. Using standard PCIT completion criteria, 4 families completed treatment; and these families demonstrated clinically significant change on observational and self-report measures of parent behavior, parenting stress, and child functioning. Although treatment dropouts demonstrated more attenuated changes, observational data and parent-reported problems across sessions indicated some improvements with lower doses of intervention. Attendance and adherence data, referral source, barriers to treatment participation, and treatment satisfaction across completers and dropouts are discussed to highlight differences between the current sample and prior PCIT research. The findings suggest that PCIT can be delivered successfully in an underserved community sample when families remain in treatment, but that premature dropout limits treatment effectiveness. The findings suggest potential directions for research to improve uptake of PCIT in a community service setting.
Unified dynamics of electrons and photons via Zitterbewegung and spin-orbit interaction

We show that when an electron or photon propagates in a cylindrically symmetric waveguide, it experiences both a zitterbewegung effect and a spin-orbit interaction leading to identical propagation dynamics for both particles. Applying a unified perturbative approach to both particles simultaneously, we find that to first-order in perturbation theory their Hamiltonians each contain identical Darwin (zitterbewegung) and spin-orbit terms, resulting in the unification of their dynamics. The presence of the zitterbewegung effect may be interpreted physically as the delocalization of the electron on the scale of its Compton wavelength, or the delocalization of the photon on the scale of its wavelength in the waveguide. The presence of the spin-orbit interaction leads to the prediction of several rotational effects: the spatial or time evolution of either particle's spin/polarization vector is controlled by the sign of its orbital angular momentum quantum number, or conversely, its spatial wave function is controlled by its spin angular momentum.
Effects of interleukin-1 infused into brain are antagonized by α-MSH in a dose-dependent manner

Abstract Interleukin-1 (IL-1) in the brain stimulates the pituitary-adrenal axis and markedly suppresses cellular immune responses. α-Melanocyte-stimulating hormone (α-MSH) introduced into the ventricular system simultaneously with IL-1 blocked these effects of IL-1 in a dose-dependent manner, with 10 ng of α-MSH totally blocking the elevation of plasma ACTH and corticosterone and suppression of Natural Killer (NK) cell activity produced by a dose of IL-1 (100 pg) that otherwise causes maximal effects. In that IL-1 has been shown to promote production of α-MSH, these results suggest that actions of IL-1 in brain are under negative feedback control and, consequently, that the effects of this cytokine in brain are of biological significance.
Extended classical over-barrier model for collisions of highly charged ions with conducting and insulating surfaces

We have extended the classical over-barrier model to simulate the neutralization dynamics of highly charged ions interacting under grazing incidence with conducting and insulating surfaces. Our calculations are based on simple model rates for resonant and Auger transitions. We include effects caused by the dielectric response of the target and, for insulators, localized surface charges. Characteristic deviations regarding the charge-transfer processes from conducting and insulating targets to the ion are discussed. We find good agreement with previously published experimental data for the image energy gain of a variety of highly charged ions impinging on Au, Al, LiF, and KI crystals. @S1050-2947~98!01001-4#
Numerical Simulation for Collision and Growth of Inclusions in Ladles Stirred with Different Porous Plug Configurations

A mathematical model has been developed to predict the collision and aggregation among inclusions in the ladle with different porous plug configurations. The numerical results showed that the porous plug configuration has a profound effect on the inclusion removal process in ladle. The eccentric bottom blowing is better than the central bottom blowing. The terminal inclusion removal efficiency decreases with the increasing porous plugs. The inclusions captured by the top slag accounts for the majority of the removed inclusions, inclusion adhesion to the sidle wall is the minor manner, and inclusions adhered to the ladle bottom wall can be negligible. In order to avoid newly generated large inclusions to be remained in the liquid steel after about 16 min of treatment, it is necessary to prolong the treating time on the condition of one porous plug configuration.
Characterization of axo‐axonic synapses in the piriform cortex of Mus musculus

Previous anatomical and physiological studies have established major glutamatergic and GABAergic neuronal subtypes within the piriform cortical circuits. However, quantitative information regarding axo-axonic inhibitory synapses mediated by chandelier cells across major cortical subdivisions of piriform cortex is lacking. Therefore, we examined the properties of these synapses across the entire piriform cortex. Our results show the following. 1) γ-Aminobutyric acid membrane transporter 1-positive varicosities, whose appearance resembles chandelier cartridges, are found around the initial segments of axons of glutamatergic cells across layers II and III. 2) Both the density of axo-axonic cartridges and the degree of γ-aminobutyric acid membrane transporter 1 innervation in each axo-axonic synapse are significantly higher in the piriform cortex than in the neocortex. 3) Glutamate decarboxylase 67, vesicular GABA transporter, and parvalbumin, but not calbindin, are colocalized with the presynaptic varicosities, whereas gephyrin, Na-K-2Cl cotransporter 1, and GABA(A) receptor α1 subunit, but not K-Cl cotransporter 2, are colocalized at the presumed postsynaptic sites. 4) The axo-axonic cartridges innervate the majority of excitatory neurons and are distributed more frequently in putative centrifugal cells and posterior piriform cortex. We further describe the morphology of chandelier cells by using parvalbumin-immunoreactivity and single-cell labeling. In summary, our results demonstrate that a small population of chandelier cells mediates abundant axo-axonic synapses across the entire piriform cortex. Because of the critical location of these inhibitory synapses in relation to action potential regulation, our results highlight a critical role of axo-axonic synapses in regulating information flow and olfactory-related oscillations within the piriform cortex in vivo.
Khruschov's rule and the abrasive wear resistance of multiphase solids

Abstract Khruschov has pointed out that the abrasive wear resistance of composites can often be expressed as ∑iυiϵi where υi and ϵi are the volume fraction and wear resistance of the ith phase. This expression accurately predicts the wear resistance of metal composites but not of composites of metals and ceramic materials. While the volume abrasive wear rates of metals are believed to be proportional to the applied load, there is evidence that the volume wear rates of ceramic materials can be non-linear functions of both the applied load and the area of the abraded surface. The abrasive wear resistance of a model composite system is considered for steady state wear. For this system it can be shown that the relationship suggested by Khruschov is realized if the volume wear rates of the phases constituting the composite are proportional to the load. However, the relationship does not hold if the volume wear rates of the individual phases depend on the area or are non-linearly related to the load.
Forces of Nature Affect Implicit Connections With Nature

The purpose of this study was to examine whether seasonal and meteorological changes in nature correspond to environmental attitudes and concerns. An implicit connection to nature task, environmental concern scale, and conservation behavior survey were administered to 220 participants across spring, autumn, and winter seasons in a temperate region of the United States. These behavioral data were correlated with temperature and precipitation data from the U.S. National Weather Service. Results indicated seasonal and meteorological factors were associated with performance on the implicit task, but not explicit, environmental attitudes and self-reported behaviors. These findings suggested contextual influences in the natural environment correspond to implicit connectedness with nature.
Enrichment of Intestinal Mucosal Phospholipids with Arachidonic and Eicosapentaenoic Acids Fed to Suckling Piglets Is Dose and Time Dependent

Infant formula companies began fortifying formulas with long-chain PUFA in 2002, including arachidonic acid (ARA) at approximately 0.5% of total fatty acids. The primary objective of this study was to determine the time-specific effects of feeding formula enriched with supra-physiologic ARA on fatty acid composition of intestinal mucosal phospholipids. One-day-old pigs (n = 96) were fed a milk-based formula for 4, 8, or 16 d. Diets contained either no PUFA (0% ARA, negative control), 0.5% ARA, 2.5% ARA, 5% ARA, or 5% eicosapentaenoic acid (EPA) of total fatty acids (wt:wt). Growth (299 +/- 21 g/d) and clinical hematology were unaffected by treatment (P > 0.6). Although minimal on d 4, concentrations of ARA in jejunal mucosa were enriched 47, 272 and 428% by d 8 and 144, 356, and 415% by d 16 in pigs fed the 0.5% ARA, 2.5% ARA, and 5% ARA diets, respectively, compared with the 0% ARA control pigs (P 50%. As ARA increased, linoleic acid content decreased reciprocally. Although maximal enterocyte enrichment with EPA approached 20-fold by d 8, concentrations were only approximately 50% of those attained for ARA. Negligible effects on gross villus/crypt morphology were observed. These data demonstrate a dose-dependent response of intestinal mucosal phospholipid ARA concentration to dietary ARA with nearly full enrichment attained within 8 d of feeding formula containing ARA at 2.5% of total fatty acids and that supra-physiologic supplementation of ARA is not detrimental to growth.
Removal of ammonia from air on molybdenum and tungsten oxide modified activated carbons.

Microporous coconut-based activated carbon was impregnated with solutions of ammonium metatungstate or ammonium molybdate and then calcined in air in order to convert the salts into their corresponding oxides. The surface of those materials was characterized using adsorption of nitrogen, potentiometric titration, Fourier-transform infrared spectroscopy, X-ray diffraction, and thermal analysis. The results indicated a significant increase in surface acidity related to the presence of tungsten or molybdenum oxides. On the materials obtained, adsorption of ammonia from either dry or moist air was carried out. The oxides distributed on the surface provided Lewis and/or Bronsted centers for interactions with ammonia molecules or ammonium ions. Water on the surface of carbon or in the gas phase increased the amount of ammonia adsorbed via involvement of Bronsted-type interactions and/or by leading to the formation of molybdate or tungstate salts on the surface. Although the amount of ammonia adsorbed is closely related to the number of moles of oxides and their acidic centers, the carbon surface also contributes to the adsorption via providing small pores where ammonia can be dissolved in the water film.
Effects of isoproterenol, theophylline and carbachol on cyclic nucleotide levels and relaxation of bovine tracheal smooth muscle.

Abstract The effect of theophylline and isoproterenol on bovine tracheal smooth muscle tension and cyclic AMP levels was investigated. Concentrations of isoproterenol (4 × 10 −6 M) and theophylline (10 mM) that relaxed carbachol-contracted tracheal muscle by 85–95% did not significantly elevate control levels of cyclic AMP. In the absence of carbachol, several-fold increases in cyclic AMP were caused by isoproterenol although no elevations by theophylline were measurable. However, when isoproterenol and theophylline were administered together, theophylline potentiated the rise in cyclic AMP caused by isoproterenol. Phosphodiesterase studies in tracheal muscle showed the presence of a high and a low K m enzyme which were inhibited by theophylline. Cyclic GMP levels were elevated in muscles contracted by carbachol as well as in carbachol-contracted muscles that had been relaxed by theophylline. In non-tension studies, in which the tracheal muscle was not under isometric tension, carbachol or theophylline alone increased cyclic GMP and together they synergistically elevated cyclic GMP. Atropine blocked the elevation caused by carbachol but not that caused by theophylline. In contrast to theophylline, isoproterenol did not elevate cyclic GMP, and in carbachol-contracted muscles that had been relaxed by isoproterenol, cyclic GMP levels were no different from control. Also, in non-tension studies, isoproterenol decreased basal cyclic GMP and antagonized the increase in cyclic GMP due to carbachol. The results indicate that whole-tissue levels of cyclic AMP and cyclic GMP do not correlate with the state of tracheal smooth muscle tension. Cyclic GMP levels do not clearly correlate with either contraction or relaxation. The inhibition by carbachol of increases in cyclic AMP due to isoproterenol and the inhibition by isoproterenol of increases in cyclic GMP due to carbachol provide evidence for a reciprocal cholinergic-adrenergic antagonism of cyclic AMP and cyclic GMP levels. The antagonism did not appear to be due to either cyclic nucleotide affecting the elevation of the other since the levels of both cyclic nucleotides were depressed.
Modeling of inhibition/excitation firing in olfactory bulb through spiking neurons

Spiking neural systems are based on biologically inspired neural models of computation since they take into account the precise timing of spike events and therefore are suitable to analyze dynamical aspects of neuronal signal transmission. These systems gained increasing interest because they are more sophisticated than simple neuron models found in artificial neural systems; they are closer to biophysical models of neurons, synapses, and related elements and their synchronized firing of neuronal assemblies could serve the brain as a code for feature binding and pattern segmentation. The simulations are designed to exemplify certain properties of the olfactory bulb (OB) dynamics and are based on an extension of the integrate-and-fire (IF) neuron, and the idea of locally coupled excitation and inhibition cells. We introduce the background theory to making an appropriate choice of model parameters. The following two forms of connectivity offering certain computational and analytical advantages, either through symmetry or statistical properties in the study of OB dynamics have been used: a) all-to-all coupling, b) receptive field style coupling. Our simulations showed that the inter-neuron transmission delay controls the size of spatial variations of the input and also smoothes the network response. Our IF extended model proves to be a useful basis from which we can study more sophisticated features as complex pattern formation, and global stability and chaos of OB dynamics.
THE 3'-5' EXONUCLEASE SITE OF DNA POLYMERASE III FROM GRAM-POSITIVE BACTERIA : DEFINITION OF A NOVEL MOTIF STRUCTURE

The primary structure of the 3′–5′ exonuclease (Exo) site of the Gram+ bacterial DNA polymerase III (Pol III) was examined by site-directed mutagenesis of Bacillus subtilis Pol III (BsPol III). It was found to differ significantly from the conventional three-motif substructure established for the Exo site of DNA polymerase I of Escherichia coli (EcPol I) and the majority of other DNA polymerase-exonucleases. Motifs I and II were conventionally organized and anchored functionally by the predicted carboxylate residues. However, the conventional downstream motif, motif III, was replaced by motif IIIe, a novel 55-amino-acid (aa) segment incorporating three essential aa (His565, Asp533 and Asp570) which are strictly conserved in three Gram+ Pol III and in the Ec Exo epsilon (e). Despite its unique substructure, the Gram+ Pol III-specific Exo site was conventionally independent of Pol, the site of 2′-deoxyribonucleoside 5-triphosphate (dNTP) binding and polymerization. The entire Exo site, including motif IIIe could be deleted without profoundly affecting the enzyme's capacity to polymerize dNTPs. Conversely, Pol and all other sequences downstream of the Exo site could be deleted with little apparent effect on Exo activity. Whether the three essential aa within the unique motif IIIe substructure participate in the conventional two-metal-ion mechanism elucidated for the model Exo site of EcPol I, remains to be established.
GX 340+0 as a Hot Neutron Star

MARGON et al.1 have shown the X-ray spectrum of GX 340+0 to be consistent, in the range 1–10 keV, with that of a black-body of radius 8±4 km at a temperature Te≃ 1.5×107 K. This source has many of the expected properties of thermal radiation from a relatively massive neutron star. Margon et al. quote Tsuruta and Cameron2 as indicating the cooling time for such a star to be at most a few years; they are therefore forced to postulate a somewhat strained accretion process to understand such a high temperature.
Perturbation of EGF-induced MAP kinase activation by TGF-beta 1.

TGF-s1 regulates both cellular growth and phenotypic plasticity important for maintaining a growth advantage and increased invasiveness in progressively malignant cells. Recent studies indicate that TGF-s-1 stimulates the conversion of epitheliod to fibroblastoid phenotype which presumably leads to the inactivation of growth-inhibitory effects by TGF-s1 (Portella et al. (1998) Cell Growth and Differentiation, 9: 393-404). Therefore, the investigation of TGF-s1 signaling that leads to altered growth and migration may provide novel targets for the prevention of increased cell growth and invasion. Although much attention has been paid to TGF-s1 responses in epithelial cells, the above studies suggest that examination of signal transduction pathways in fibroblasts are important as well. Data from our laboratory are consistent with the concept that TGF-s1 can act as a regulatory switch in density-dependent C3H 10T1/2 fibroblasts capable of either promoting or delaying G1 traverse. The regulation of this switch is proposed to occur prior to pRb phosphorylation, namely prior to activation of cyclin-dependent kinases. The current study is concerned with the evaluation of a key cyclin (cyclin D1) which activates cdk4 and p27KIP1 which in turn inhibit cdk2 in the proliferative responses of epidermal growth factor (EGF) and platelet-derived growth factor (PDGF) and their modulation by TGF-s1. Although the molecular events that lead to elevation of cyclin D1 are not completely understood, it appears likely that activation of p42/p44MAPK kinases is involved in its transcriptional regulation. TGF-s1 delayed EGF- or PDGF-induced cyclin D1 expression and blocked the induction of active p42/p44MAPK. The mechanism by which TGF-s1 induces a block in p42/p44MAPK activation is being examined and the possibility that TGF-s1 regulates phosphatase activity is being tested.
Clinical studies of gonadotropins in the female.

Clinical studies of gonadotropins in the female are reviewed. Areas discussed include fetal gonadotropins the role of gonadotropins in ovarian maturation precocious puberty pseudopuberty and delayed puberty the pattern of luteinizing hormone and follicle stimulating hormone secretion over the menstrual cycle spontaneous fluctuations in daily gonadotropin levels correlations between steroid levels and gonadotropin levels during events of the menstrual cycle the feedback mechanism of gonadotropin secretion. and the role of gonadotropins in cases of anovulation amenorrhea ovulation induction human chorionic gonadotropin secretion and in the postmenopausal period.
Effects of microwave exposure on the hamster immune system. III. Macrophage resistance to vesicular stomatitis virus infection.

Exposure of hamsters to microwave (MW) energy (2.45 GHz, 25 mW/cm2, 1 h) resulted in activation of peritoneal macrophages (PM) to a viricidal state restricting the replication of vesicular stomatitis virus (VSV). The PM from MW-exposed hamsters were viricidal as early as 1 day after exposure and remained active for 5 days. Immunization of hamsters with vaccinia virus induced viricidal PM by 3 to 4 days and they remained active for 7 days. To test the hypothesis that thermogenic MW exposure results in the release of endotoxin across the intestinal epithelium which subsequently activates PM, hamsters were injected with lipopolysaccharide (LPS) and their viricidal activity was studied. Lipopolysaccharide in vitro (0.2 microgram) and in vivo (0.5 microgram) activated macrophages to a viricidal state. When administered in vivo, LPS (0.5 microgram) activated macrophages as early as 1 day and the activity remained for 3 days. While MW exposure of PM in vitro failed to induce viricidal activity, exposure of PM to LPS in vitro induced strong viricidal activity. This suggests that the in vivo response of PM to MW is an indirect one, which is consistent with the hypothesis that MW-induced PM viricidal activity may be mediated via LPS. In preliminarymore » experiments, MW exposure resulted in extended survival time for hamsters challenged with a lethal dose of vesicular stomatitis virus, supporting the concept that MW-activated PM may be a useful therapeutic modality.« less
Diastereoselective Synthesis of 2,3,6-Trisubstituted Piperidines

We report the diastereoselective and chromatography-free syntheses of four 2-phenyl-6-alkyl-3-aminopiperidines. Ring construction was accomplished through a nitro-Mannich reaction linking a nitroketone and phenylmethanimine, followed by a ring-closure condensation. Relative stereocontrol was achieved between C-2 and C-3 by kinetic protonation of a nitronate or by equilibration of the nitro group under thermodynamic control. Stereocontrol at C-6 was accomplished by utilizing a variety of imine reduction methods. The C-2/C-6-cis stereochemistry was established via triacetoxyborohydride iminium ion reduction, whereas the trans relationship was set either by triethylsilane/TFA acyliminium ion reduction or by Lewis acid catalyzed imine reduction with lithium aluminum hydride.
Amperometric Biosensor for Adenosine-5′-Triphosphate Based on a Platinum-Dispersed Carbon Paste Enzyme Electrode

Abstract A new amperometric biosensor for adenosine-5′-triphosphate (ATP) was designed using a platinum-dispersed carbon paste into which glycerol kinase and glycerol-3-phosphate oxidase were incorporated. The biosensor is based on the detection of hydrogen peroxide produced by the enzymatic reaction of ATP with glycerol and the subsequent oxidation of glycerol-3-phosphate. The use of the platinum-dispersed carbon paste electrode lowered the oxidation potential for hydrogen peroxide, permitting the sensitive detection of ATP at 0.4 V vs. Ag/AgCl. A linear response to ATP was observed in the concentration range of 1 x 10−5 to 2.5 x 10−3 M. Permanent address: Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Okayama 700, Japan.
Effects of the Zebra Mussel, Dreissena polymorpha, on Community Nitrogen Dynamics in Saginaw Bay, Lake Huron

The effects of the zebra mussel, Dreissena polymorpha, on chlorophyll and nutrient concentration changes and community ammonium uptake and regeneration rates were determined in bottle experiments on waters collected from a eutrophic site and an oligotrophic site in Saginaw Bay, Lake Huron in 1992. Our objectives were to estimate nitrogen cycling rates and to determine the direct (excretion) and indirect (foodweb) effects of the zebra mussel on these rates. Isotope labeling experiments with added 15NH4+ were conducted on waters collected on five sampling dates between April and October. Direct effects of zebra mussels on ammonium regeneration and potential uptake were examined by comparing results from bottles incubated with (15 individuals in 4 L lake water) and without added zebra mussels. Indirect foodweb effects were examined by measuring regeneration and potential uptake rates in subsamples of water that had previously been incubated in the presence or absence of zebra mussels. Zebra mussels removed a large fraction of chlorophyll from the oligotrophic site on all sampling dates and from the eutrophic site in October, but had a negligible effect on chlorophyll levels in waters from the eutrophic site in June, July, August, and September when cyanophytes were abundant. Community ammonium regeneration rates and uptake rates both followed seasonal patterns resembling those for chlorophyll concentrations in control treatments at the eutrophic site. Rates for water from the oligotrophic site were low (usually not significantly different from zero) and are not reported here. Community ammonium regeneration rates were consistently enhanced in the presence of zebra mussels, indicating that zebra mussel excretion could have a dominant effect on nitrogen regeneration in regions where it is abundant. Zebra mussels appeared to decrease community uptake rates of ammonium in August and September but did not predictably affect nitrogen remineralization rates by other lower foodweb organisms (e.g. bacteria, protozoans, zooplankton).
Labeling deoxyribonucleic acid to high specific activity in vitro by nick translation with DNA polymerase I

Circular (e.g. simian virus 40) and linear (e.g. λ phage) DNAs have been labeled to high specific radioactivities (>108 cts/min per μg) in vitro using deoxynucleoside [α-32P]triphosphates (100 to 250 Ci/mmol) as substrates and the nick translation activity of Escherichia coli DNA polymerase I. The reaction product yields single-stranded fragments about 400 nucleotides long following denaturation. Because restriction fragments derived from different regions of the nick-translated DNA have nearly the same specific radioactivity (cts/min per 10[su3] bases), we infer that nicks are introduced, and nick translation is initiated, with equal probability within all internal regions of the DNA. Such labeled DNAs (and restriction endonuclease fragments derived from them) are useful probes for detecting rare homologous sequences by in situ hybridization and reassociation kinetic analysis.
Control of Death-associated Protein Kinase (DAPK) Activity by Phosphorylation and Proteasomal Degradation

Activation of death-associated protein kinase (DAPK) occurs via dephosphorylation of Ser-308 and subsequent association of calcium/calmodulin. In this study, we confirmed the existence of the alternatively spliced human DAPK-β, and we examined the levels of DAPK autophosphorylation and DAPK catalytic activity in response to tumor necrosis factor or ceramide. It was found that DAPK is rapidly dephosphorylated in response to tumor necrosis factor or ceramide and then subsequently degraded via proteasome activity. Dephosphorylation and activation of DAPK are shown to temporally precede its subsequent degradation. This results in an initial increase in kinase activity followed by a decrease in DAPK expression and activity. The decline in DAPK expression is paralleled with increased caspase activity and cell apoptosis. These results suggest that the apoptosis regulatory activities mediated by DAPK are controlled both by phosphorylation status and protein stability.
The principle of least action and fundamental solution of two-point boundary value problems in orbital mechanics

The two-point boundary value problem (TPBVP) in orbital mechanics involving a small body (e.g., a spacecraft or asteroid) and N larger bodies is considered. The least action principle TPBVP formulation is converted into an initial value problem via the addition of an appropriate terminal cost to the action functional. The latter formulation is used to obtain a fundamental solution, which may be used to solve the TPBVP for a variety of boundary conditions within a certain class. In particular, the method of convex duality allows one to interpret the least action principle as a differential game, where an opposing player maximizes over an indexed set of quadratics to yield the gravitational potential. In the case where the time-duration is less than a specific bound, the fundamental solution is obtained as a set of solutions of Riccati equations associated with the resulting differential game.
Individual differences and system development

Using an order of magnitude more subjects, this replication of a study by Dos Santos and Hawk confirms its finding that system development professionals' attitudes can be classified as user-oriented, technically-oriented, or socio-politically-oriented. Furthermore, we found that these attitudes are related to such demographic individual differences as age, education, system development experience, and managerial position. We also looked for differences by gender, but the data do not support differences in attitude according to gender.