cssi/SciSciGPT-SciSciNet huggingface dataset:
Differences in Dissolved Organic Carbon and Nitrogen Responses to Storm-Event and Ground-Water Conditions in a Forested, Glaciated Watershed in Western New York1

: Differences in the storm-event responses of dissolved organic carbon (DOC) and nitrogen (DON) in streamflow and ground water were evaluated for a glaciated forested watershed in western New York. Eight to ten storm events with varying rainfall amounts, intensities, and antecedent moisture conditions were studied for three catchments (1.6, 3.4, and 696 ha) over a three-year period (2003-2005). Concentrations of DOC in streamflow exiting the catchments were significantly higher for storm events following a dry period, whereas no similar response was observed for DON. Highest DON concentrations in streamflow were typically associated with storm events following wet antecedent moisture conditions. In addition to antecedent moisture conditions, DOC concentrations were also positively correlated with precipitation amounts, while DON did not reveal a consistent pattern. Streamwater and ground-water concentrations of DOC during storm events were also strongly correlated with riparian ground-water depths but a similar relationship was not observed for DON. Ground-water DON concentrations were also more variable than DOC. We hypothesized that the differences in DOC and DON responses stemmed from the differences in catchment sources of these solutes. This study suggests that while DOC and DON are intrinsically linked as components of dissolved organic matter, their dynamics and exports from watersheds may be regulated by a different set of mechanisms and factors. Identifying these differences is critical for developing more reliable and robust models for transport of dissolved organic matter.
Reconstructing brain white matter pathways with diffusion tensor MRI using kernel-based diffusion simulations

A novel algorithm for approximating anatomical brain connectivity in vivo is presented using diffusion tensor magnetic resonance imaging (DT-MRI). This technique relies on simulating diffusion process within a series of overlapping three dimensional diffusion kernels that cover only a small portion of the human brain volume. The shape of the anisotropic diffusion represented by diffusion fronts is used to estimate the directional organization of the underlying white matter fiber tracts. The proposed algorithm is tested on both simulated and real DT-MRI data. The demonstration shows that the synthetic tracts are accurately replicated, while various examples of white matter fiber pathways can be reconstructed as well, with assigned connectivity indices showing uncertainty. Several features of the algorithm are elucidated by the tracking experiments, including its capability of handling fiber branching and crossing, and robustness to noise. Impact of thresholding settings and the kernel size on performance o...
Proton ENDOR studies of soliton wave functions and dynamics in polyacetylenes

Electron nuclear double resonance (ENDOR) studies were carried out over a range of temperatures for five different preparations of polyacetylenes (PAs): Shirakawa (trans-PA), Shirakawa (cis-PA), Durham PA, Naarmann PA, and “enolic PA”. EPR and magnetic susceptibility (SQUID) measurements were also performed and correlated with ENDOR measurements. Whereas the same quasi-delocalized paramagnetic defect (“soliton”) appears to give rise to the ENDOR spectra for all preparations, the extent and dynamics of the soliton defect vary significantly with different preparations illustrating the importance of the lattice (cross-links, residual catalyst, elimination products, adjacent polyene chains, etc.) surrounding and terminating a soliton in defining apparent delocalization of the observed soliton. The analysis of the temperature dependence of ENDOR spectra is complicated by the relatively high concentration of paramagnetic solitons, which may facilitate exchange narrowing of ENDOR spectra. The ambiguity of wheth...
A wheat genomic DNA fragment reduces pollen transmission of maize transgenes by reducing pollen viability

A genomic DNA fragment from wheat carrying the Glu-1Dx5 gene has been shown to exhibit reduced pollen transmission in transgenic maize. To localize the region of the DNA fragment responsible for this reduced pollen transmission, we produced transgenic maize plants in which the wheat genomic DNA proximal to the 1Dx5 coding sequence was replaced with the maize 27 kDa gamma-zein promoter. Like the wheat promoter-driven Glu-1Dx5 transgene, this zein promoter-driven transgene functioned to produce 1Dx5 in maize endosperm. However, with the zein promoter-driven transgene, pollen transmission of the transgene loci was normal in most self- and cross-pollinations. We concluded that the wheat genomic DNA proximal to the wheat 1Dx5 coding sequence was required for reduced pollen transmission of the transgene in maize. In two of four transformation events of the wheat promoter-driven construct examined, pollen exhibited two morphological classes. In one class, pollen was normal in morphology and displayed average viability, and in the second, pollen was reduced in size and did not germinate on artificial media. DNA from the transgene was detectable in mature pollen from plants with reduced pollen transmission of transgene loci. To explain these observations, we hypothesize that elements within the transgene construct interfere with pollen development. We demonstrated that the wheat genomic DNA fragment can be used to control pollen transmission of an herbicide resistance transgene genetically linked to it. The wheat genomic DNA fragment may contain elements that are useful for controlling pollen transmission of transgene loci in commercial maize grain and seed production.
Exploring differential gene expression in zebrafish to teach basic molecular biology skills.

Abstract In an effort to engage students in original research while teaching them basic molecular biology skills, we have designed a course for upper level undergraduate students and beginning graduate students that employs in situ hybridization in whole-mount zebrafish embryos to explore the concept of differential gene regulation. The course was taught in a workshop format during a break between the normal fall and spring semesters, which allowed students to immerse themselves in the concepts and techniques full time over a 13-day period. Overall, the course was successful in exposing students to a variety of techniques in the context of an ongoing research project in our laboratory, which provided beneficial outcomes for students and instructors alike. Here we provide a detailed account of the course organization and preparation, as well as an analysis of learning outcomes achieved by the students.
Optimum scheduling of a new maintenance program under stochastic degradation

Abstract In this paper we consider an intermittently operating system which is under periodic review and which is subject to random aging or degradation. The optimal schedule when initiating a new maintenance program is analyzed so as to minimize the long term discounted cost. The scheduled maintenance is based on the level of system degradation rather than time. The functional equation approach enables one to incorporate such factors as the fixed cost of maintenance, the recurring costs, the discount factor and the probability distribution of aging in a given period. The analysis is illustrated with an example.
Propranolol and atenolol inhibit norepinephrine spillover rate into plasma in conscious spontaneously hypertensive rats.

Radiotracer techniques capable of measuring norepinephrine clearance and spillover rate into plasma were used to test the hypothesis that the antihypertensive effects of propranolol and atenolol in conscious spontaneously hypertensive rats are associated with an inhibition of norepinephrine release from postganglionic sympathetic neurons. The 10%–15% fall in mean arterial pressure produced over 4 h by propranolol (1, 3.3 and 10 mg/kg, s. c.) and atenolol (1, 3.3 and 10 mg/kg, s. c.) was not dose-related, and only the largest dose of propranolol caused a significant bradycardia. Each dose of atenolol significantly lowered heart rate. The decrease in blood pressure caused by propranolol and atenolol was not related to the decrease in heart rate. Both propranolol and atenolol inhibited norepinephrine clearance by 12% to 16%. The 1 mg/kg doses of propranolol and atenolol significantly suppressed norepinephrine spillover rate by 21 % and 32%, respectively, at 4 h postinjection. As the dose of propranolol was increased, the inhibition of norepinephrine spillover was reversed as plasma epinephrine concentration rose by 125%. The suppression of norepinephrine spillover rate caused by atenolol was more persistent but did diminish after the 10 mg/kg dose, when plasma epinephrine concentration was elevated by 55%. Both drugs suppressed plasma renin concentration, but the inhibition of norepinephrine spillover rate by propranolol and atenolol was not related to the fall in plasma renin concentration. By comparison, treatment with the adrenergic neuron blocking agent bretylium (5, 10, 20 and 40 mg/kg, s. c.) elicited a dose-related vasodepression with no change in heart rate or plasma renin concentration. The 10 mg/kg dose of bretylium inhibited norepinephrine spillover rate by 40%, but increasing the dose did not produce a further suppression of norepinephrine spillover rate. Bretylium caused a dose-related elevation of plasma epinephrine concentration (354% increase at 40 mg/kg). In a separate study, propranolol (10 mg/kg) and bretylium (40 mg/kg) significantly increased epinephrine spillover rate by 85% and 118%, respectively. Based on these data, we conclude that the β-adrenoceptor antagonists lower blood pressure by inhibiting norepinephrine release from postganglionic sympathetic neurons.
Whole-angle-mode micromachined fused-silica birdbath resonator gyroscope (WA-BRG)

We present the fused-silica micromachined birdbath resonator gyroscope (μ-BRG) operating in the whole-angle (WA) mode. The key advantages of the whole angle mode operation is rotation angle measurement, large bandwidth, and full-scale range which is needed in detecting the motion of fast-moving objects. The μ-BRG is made with fused silica using a micro blow-torching process and has n = 2 wineglass modes at 10.46 kHz with a small frequency mismatch (Δf = 10 Hz) and a decay time (τ) of 2.2s. The WA-BRG achieves a stable angular gain (Ag) and a large full scale range (700°/s).
Analysis of microchannels for integrated cooling

Abstract Recent advances in the precision machining of small channels have made possible the use of such micro-channels in ultra compact, very efficient heat exchangers, which capitalize on the channels' large surface area to volume ratio to transport high heat fluxes with small thermal resistances. For instance, such micro-channels can be fabricated right into the back of electronic chips to effectuate the cooling of these chips. In this paper, we analyze such heat exchangers by solving numerically a conjugate heat transfer problem consisting of the simultaneous determination of the temperature fields in both the solid substrate and the fluid. Additionally, we present a design algorithm for the selection of the heat exchanger's dimensions.
A new semantic functional similarity over gene ontology

Identifying functionally similar or closely related genes and gene products has significant impacts on biological and clinical studies as well as drug discovery. In this paper, we propose an effective and practically useful method measuring both gene and gene product similarity by integrating the topology of gene ontology, known functional domains and their functional annotations. The proposed method is comprehensively evaluated through statistical analysis of the similarities derived from sequence, structure and phylogenetic profiles, and clustering analysis of disease genes clusters. Our results show that the proposed method clearly outperforms other conventional methods. Furthermore, literature analysis also reveals that the proposed method is both statistically and biologically promising for identifying functionally similar genes or gene products. In particular, we demonstrate that the proposed functional similarity metric is capable of discoverying new disease related genes or gene products.
Interactions of oxygen and inert gases in Drosopfflla

Abstract The narcotic potency for Drosophila of nitrogen (34 atm), argon (24 atm), xenon (1.7 atm), nitrous oxide (1.7 atm) and CO 2 (0.2 atm) is markedly enhanced by raising the oxygen pressure from 0.21 to 1.0 atm or more. In 1 atm of oxygen alone the flies survive about a week, but in the presence of these inert gases this tension of oxygen causes collapse in a few hours. No such synergism between oxygen and inert gases is evident with helium at similar pressures. Alcohol and ether give somewhat similar results; they shorten the survival times at all tensions of oxygen, the optimum partial pressure of oxygen for survival being displaced to values higher than in normal air.
Mechanosensitive ion channels in interstitial cells of Cajal and smooth muscle of the gastrointestinal tract

Normal gastrointestinal (GI) motility is required to mix digestive enzymes and food and to move content along the GI tract. Underlying the complex motor patterns of the gut are electrical events that reflect ion flux across cell membranes. Smooth muscle electrical activity is directly influenced by GI interstitial cells of Cajal, whose rhythmic oscillations in membrane potential in part determine the excitability of GI smooth muscle and its response to neuronal input. Coordinated activity of the ion channels responsible for the conductances that underlie ion flux in both smooth muscle and interstitial cells is a requisite for normal motility. These conductances are regulated by many factors, including mechanical stress. Recent studies have revealed mechanosensitivity at the level of the ion channels, and the mechanosensor within the channel has been identified in many cases. This has led to better comprehension of the role of mechanosensitive conductances in normal physiology and will undoubtedly lead to understanding of the consequences of disturbances in these conductances.
Application of Fixator-Norator Pairs in Designing Active Loads and Current Mirrors in Analog Integrated Circuits

Design of analog integrated circuits is discussed in this paper. The emphasis is on the biasing design of ICs using Fixator-norator pairs. Fixators are used to keep the driver transistors biased at the desirable operating points while the pairing norators are used to allocate and specify the bias-supporting components. A bias-supporting component is shown to be one of the two categories: 1) a DC voltage source or a DC current source/sink or 2) a power-conducting component. A power-conducting component is typically a resistor in lumped circuits but an active load or current mirror in an analog IC. Three types of active loads are introduced and their design is also discussed in this paper. Two examples, one in bipolar and one in CMOS technology, demonstrate the analog IC design procedure.
Non-linear frequency response characteristics of an impact pair

Abstract The method of harmonic balance is used to develop approximate analytical solutions to the equations of motion of a single impact pair including a general discussion of the existence and stability of these solutions. Non-linear frequency response characteristics are obtained for a single frequency excitation and primary resonance (no subharmonic or superharmonic response) and the results are validated using an analog computer simulation. It has been found that the use of digital simulation (numerical integration) may lead to inaccurate results over certain frequency ranges. It is also shown that, although the shapes of the force-displacement relationship for clearance non-linearity and the classic cubic non-linearity are similar, the resulting non-linear frequency response curves can be quite different. Various issues related to the clearance non-linearity problem are discussed.
What Difference a Definition Makes, or, William Dean Howells and the Sophist's Shoes

ABSTRACT Starting from a chance quotation in William Dean Howells' “Novel-Writing and Novel-Reading,” this essay reflects on the differences (and relations) between what classical tradition would call “grammatical” and “rhetorical” approaches to discourse—and, likewise, what might be called “hermeneutic” and “productive” approaches to rhetoric. The grammatical/hermeneutic approach is oriented towards reaching an understanding of what a text says or means, or what its argument is, while the rhetorical/productive approach is characterized by the questions, How was it done? and How can I do that? It is this latter approach—the orientation toward the cultivation of productive discursive skill—that disciplinarily makes rhetoric, as opposed to a variety of philosophy or literary criticism. This notion is further aligned, on one hand, with a revisionist “sophist's history of rhetoric,” and, on the other hand, with a “sophistic” approach to rhetorical education derived from the tradition of Isocrates.
Transgenic mouse blastocysts that overexpress metallothionein-I resist cadmium toxicity in vitro

The role of metallothionein with regard to cadmium toxicity in vitro was investigated using preimplantation mouse blastocysts derived from a transgenic strain that constitutively overexpresses metallothionein-I transgenes (MT-I*). Northern blot and in situ hybridization revealed high levels of MT-I mRNA in transgenic blastocysts when compared with control blastocysts, and reverse transcriptase-polymerase chain reaction-amplified MT-I mRNA was almost exclusively MT-I*. Moreover, pulse-labeling experiments showed that the relative rate of synthesis of MT was 9-fold higher in transgenic blastocysts. Cadmium (Cd 2+ ) toxicity was assessed after incubating blastocysts for 4 hr in Whitten's medium containing 50 μM Cd 2+ . Embryos that displayed abnormal morphology were judged sensitive. Transgenic blastocysts were more resistant to cadmium-induced morphological changes than were control blastocysts. Sensitive and resistant blastocysts were individually genotyped by polymerase chain reaction, or they were transferred to foster mothers, and embryonic development to midterm was monitored. Of the blastocysts derived from mating heterozygous transgenic males with control females, 56% were transgenic before incubation with Cd 2+ , whereas 95% of the blastocysts that retained normal morphology after incubation were transgenic. Moreover, after Cd 2+ exposure, transgenic blastocysts with normal morphology were nine times more likely to develop to midterm than were control blastocysts with normal morphology. Blastocysts with abnormal morphology failed to develop to midterm. These studies indicate that MT plays a central role in protection from Cd 2+ toxicity within the physiological context of the developing mouse embryo.
Helping parents of premature babies: A cognitive-behavioral approach

Having an infant in an intensive care setting is highly stressful for parents and may disrupt the bonding process. This article presents a cognitive-behavioral framework as a useful way of understanding and intervening with parents of normal, healthy, premature babies. Differences are shown between stimulus events experienced by parents of term and premature babies and the consequent differences in thoughts, feelings, and behaviors are discussed. Suggestions are made for helping parents of premature babies replace dysfunctional irrational cognitions with more appropriate and rational beliefs.
CORE COMPLEX DEVELOPMENT IN CENTRAL ANATOLIA, TURKEY

Tectonic models for the central Anatolian segment of the Alpine-Himalayan orogen have not considered this region as part of the Aegean extensional province. We have found evidence, however, for Oligocene-Miocene extension and exhumation of midcrustal rocks in a metamorphic dome (Nigde massif) that is structurally and petrologically similar to Miocene core complexes >500 km to the west. Strong correspondence in the timing and kinematic development of the Menderes (western Turkey) and Nigde core complexes suggests that extensional tectonics and exhumation of mid- to lower-crustal rocks affected much of the eastern Mediterranean region. In the Nigde massif, supracrustal rocks were buried to depths of 16‐20 km at high temperatures (>700 °C) during contraction associated with closure of Neo-Tethyan seaways in late Mesozoic‐early Cenozoic time. Following cooling and decompression to <600 °C and <10 km, metasedimentary rocks underwent a second heating event at low pressures during Miocene magmatism that postdated much of the unroofing of the massif. Development of the Nigde core complex was related to exhumation of thickened and thermally weakened continental crust in the upper plate of a north-dipping subduction zone. The partial subduction of the Tauride carbonate platform in the Eocene resulted in choking of the subduction zone, followed by isostatic rebound and exhumation of the buoyant platform. This in turn caused a rapid emergence of the upper plate, resulting in erosion of upper-crustal rocks and exhumation of midcrustal rocks along the northern edge of the Inner Tauride suture zone. Although northern regions of central Anatolia contain the same protoliths as the Nigde massif and underwent extensive Tertiary magmatism, they did not undergo similar extension, suggesting that core complex development in south-central Turkey was controlled by the location of thickened and thermally weakened crust adjacent to a suture zone.
Conversion of an Existing Complete Denture to a Temporary Obturator Prosthesis

With the advent of light-cured materials, many new opportunities for reconstruction present themselves. This brief article describes the technique for converting an existing complete denture into a temporary obturator prosthesis. This can be done chairside with minimal patient discomfort and anxiety.
Diurnal fluctuations in borehole water levels: configuration of the drainage system beneath Bench Glacier, Alaska, USA

Water levels were measured in boreholes spaced along the entire length of Bench Glacier, Alaska, USA, for a period in excess of 2 years. Instrumented boreholes were arranged as nine pairs along the center line of the glacier and an orthogonal grid of 16 boreholes in a 3600 m 2 region at the center of the ablation area. Diurnal fluctuations of the water levels were found to be restricted to the late melt season. Pairs of boreholes spaced along the length of the ablation area often exhibited similar fluctuations and diurnal changes in water levels. Three distinct and independent types of diurnal fluctuations in water level were observed in clusters of boreholes within the grid of boreholes. Head gradients suggest water did not flow between clusters, and a single tunnel connecting the boreholes could not explain the observed pattern of diurnal water-level fluctuations. Inter-borehole and borehole- cluster connectivity suggests the cross-glacier width of influence of a segment of the drainage system connected to a borehole was limited to tens of meters. A drainage configuration whereby boreholes are connected to a somewhat distant tunnel by drainage pipes of differing lengths, often hundreds of meters, is shown with a numerical test to be a plausible explanation for the observed borehole behavior.
Race-Ethnicity, Education, and Employment After Spinal Cord Injury:

The objective of this article was to identify the relationship between race-ethnicity and employment after spinal cord injury (SCI), while evaluating interrelationships with gender, injury severity...
Two Basque accentual systems and the notion of pitch-accent language

The term ‘pitch-accent language’ is used in reference to languages like Swedish, where words contrast in the melody associated with the stressed syllable, and it is also applied to languages like Tokyo Japanese, where words have at most one syllable specified as bearing a tonal contour (accent), including an unaccented class. Both types of ‘pitch-accent language’ are found in different Basque dialects: Coastal Bizkaian Basque varieties have a prosodic system that resembles that of Tokyo Japanese and some local dialects of western Navarre, such as Goizueta, have a system of the Swedish type. Here I explore the lexical distribution of prosodic classes in Goizueta Basque and sketch a possible diachronic scenario to account for lexical correspondences between Goizueta and Coastal Bizkaian. I suggest, as a hypothesis, that, at the most recent common stage, the language had a prosodic system with three classes of words, two classes lexically specified for one of two types of tonal contour plus an unaccented class. The typological interest of this investigation is that it leads us to reconsider whether there is in fact some deep commonality underlying these seemingly so different types of pitch-accent system by establishing a possible diachronic link.
Problems in calculating parity ratios for nuclear level densities with the Fermi gas model.

The Fermi gas model is widely used in calculating nuclear level densities. With the use of modern computers, calculations can be made including both pairing and shell effects. Despite these improvements, there are indications that the model fails to properly predict the parity ratio even in situations where the level density itself is correctly described. A detailed examination of the discrepancies for some specific systems is presented.
Differentiation of resistance in cattle to larval Hypoderma lineatum.

Abstract Cattle were successively infested for 4 years with larval cattle grubs, Hypoderma lineatum, to demonstrate the acquisition of resistance. The effects of host age and dietary-induced state with Vitamin A on susceptibility to infestation and their interactions with effects from previous infestations were also determined. Cattle acquired resistance to infestation after a single infestation. This resistance was not affected by host age for at least 4 years, was not affected by a deficiency of vitamin A, and was effective in the skin and connective tissues of the host. The effects of this acquired resistance were highly variable in degree, were produced primarily during the first 90 days of infestation and increased after repeated provocation to provide nearly complete protection in some animals. Calves and yearlings had innate resistance that decreased with age, was localized in the skin, was impaired by a deficiency of Vitamin A, and resulted in a mean loss of 65–75% of the larvae in an infestation dose of up to 150. The combined effects of the 2 types of resistance reduced the grub-burden in cattle throughout their life.
Nerve growth factor-induced neuronal differentiation of PC12 pheochromocytoma cells: Lack of inhibition by a tumor promoter

Abstract Reports of inhibition of vitro neuronal and non-neuronal differentiation by tumor promote prompted the study of effects of phorbol myristate acetate (PMA), a potent tumor promoter, on PC12 rat pheochromocytoma cells. PC12 cells are a well characterized in vitro cell line which undergoes initiation of neurite outggrowth transcription-requiring cellular response to nerve growth factor (NGF). Cells which have been incubated in the presence of NGF for a week also acquire the capacity for rapid, transcription-independent regeneration of neurites. This capacity is known as ‘NGF-priming’. We show that PMA does not inhibit initiation, regeneration, or NGF-priming of PC12 cells. This contrasts with previously reported inhibitory effects of PMA on neurite outgrowth in other cell types. However, morphologic l changes induced by PMA in PC12 cells are consistent with reduced neurite-substrate adhesion. PMA appears to shift the dose-response curve of NGF so that low doses of NGF are more effective in initiating neurite outgrowth.
Army-Navy Precipitation-Static Project: Part I-The Precipitation-Static Interference Problem and Methods for Its Investigation

In order to provide a background for the detailed technical papers of the series, the organization, objectives, and problems of the joint Army-Navy Precipitation Static Project are reviewed. The main lines of attack and the mechanisms responsible for the production of corona and radio interference on aircraft are discussed.
A mathematical model of the grinding wheel profile required for a specific twist drill flute

Abstract Obtaining a straight cutting edge in the case of small twist drills warrants an accurate grinding of the “primary” flute. A transformed mathematical model which would yield the proper flute-grinding wheel profile for a straight cutting edge is developed from an existing orthogonal flute model. Also discussed in this paper is a mathematical model that describes the wheel profile for the “secondary” (non-cutting edge) flute as a function of parameters such as land width, web thickness and chip removal capacity of the drill. The model enables an analysis of the effects of improper wheel setting and point grinding on the straightness of the cutting edge. From this analysis, an optimum wheel profile that would grind a maximum number of acceptable flutes can be obtained.
Complications following radiation therapy to the head

A case is presented in which a child who received therapeutic radiation as part of his treatment regimen for rhabdomyosarcoma of the infratemporal and parapharyngeal region demonstrated undesirable sequelae in the dentition and the mandible.
Self-report scales of hypnotic depth.

Abstract Hypnotic “depthyy is a complex theoretical concept, for which no direct measures exist at present, but which is reflected in various experiential and behavioral responses to hypnosis. Thirty-five Ss were asked to scale their depth of hypnosis on a 10-point scale after each suggestibility test item on the Stanford Hypnotic Susceptibility Scale, Form C (Weitzenhoffer & Hilgard, 1962). These self-reports were highly correlated with measures of hypnotic behavior and experience. Instructions to report depth immediately and without thinking produced reports which correlated somewhat better with the other measures than instructions to consciously make a best estimate. This self-report scale promises to be highly useful in studies of hypnosis.
Copper modulates the phenotypic response of activated BV2 microglia through the release of nitric oxide.

Microglia are resident immune cells of the central nervous system. Their persistent activation in neurodegenerative diseases, traditionally attributed to neuronal dysfunction, may be due to a microglial failure to modulate the release of cytotoxic mediators such as nitric oxide (NO). The persistent activation of microglia with the subsequent release of NO vis-a-vis the accumulation of redox transition metals such as copper (Cu) in neurodegenerative diseases, prompted the hypothesis that copper would alter NO signaling by changing the redox environment of the cell and that, by altering the fate of NO, microglia would adopt a different phenotype. We have used the microglial cell model, BV2, to examine the effects of Cu(I) on NO production and activation as they have been shown to be phenotypically plastic. Our results show that cell viability is not affected by Cu(I) in BV2 microglia and that it has no effect on iNOS mRNA, protein expression and nitrite release. However, when LPS is added to Cu(I)-treated medium, nitrite release is abrogated while iNOS expression is not significantly altered. This effect is Cu(I)-specific and it is not observed with other non-redox metals, suggesting that Cu(I) modulates NO reactivity. Immunofluorescence analysis shows that the M1 (inflammatory) phenotype of BV2 microglia observed in response to LPS, is shifted to an M2 (adaptive) phenotype when Cu(I) is administered in combination with LPS. This same shift is not observed when iNOS function is inhibited by 1400W. In the present study we show that Cu(I) modulates the release of NO to the media, without altering iNOS expression, and produces phenotypic changes in BV2 microglia.
Stimulus similarity and positive induction

In order to assess the effect of stimulus similarity on the magnitude of positive induction, the keypeck responses of two pigeons were reinforced in the presence of one of three line orientations on a three-ply multiple schedule with identical variable-interval 2-min schedules of reinforcement associated with each component. The constant-component and variable-component stimuli remained unchanged. The altered-component stimulus was systematically varied to increase or decrease its similarity to the variable-component stimulus, while the variable-component reinforcement schedule was periodically changed to a differential- reinforcement-of-high-rate schedule. Positive induction occurred in six out of eight conditions, and the magnitude of the positive induction was a direct function of stimulus similarity. These results are not accounted for by Terrace’s (1966) interpretation of multiple-schedule interactions.
Modulus anisotropy and shear stability of geofiber-stabilized sands

A systematic laboratory approach is established to evaluate shear stability or bearing capacity improvement of sand-geofiber stabilization for rapid road and airfield construction. The approach deals with the investigation of directional dependency, anisotropy, and modulus properties and links stability to shear stress levels typically applied on specimens during testing in relation to their strength. An advanced triaxial testing machine referred to as the University of Illinois FastCell is used together with direct shear tests for determining the anisotropic resilient moduli and the strength properties of two geofiber-reinforced sands (poorly and uniformly graded sands) prepared with three 51-mm geofibers: fibrillated, monofilament, and tape. The use of different geofiber types and the various amounts of clay and silt fines present in the sand mixtures significantly affected the recorded horizontal and vertical moduli and the shear stresses at applied stress states. Monofilament-type geofiber stabilizati...
A Single Dose of the Ovotoxicant 4-Vinylcyclohexene Diepoxide Is Protective in Rat Primary Ovarian Follicles

Repeated dosing of rats with the ovotoxic chemical, 4-vinylcyclohexene diepoxide (VCD), destroys primordial and primary ovarian follicles via apoptosis (physiological cell death) by accelerating the normal rate of atresia. The present study investigated the effect of a single dose (1×) of VCD. Immature (d28) female Fischer 344 rats were dosed 1× or 15× with VCD (80 mg/kg ip). Ovaries were collected 24 h or 15 days following 1× VCD or after 15× for classification and evaluation. Following 1× VCD the number of healthy primary follicles was greater (p < 0.05) than control 24 h and 15 days later. This effect reflected a slowing of the normal rate of atresia seen in control ovaries. There was no effect of a single dose on primordial or growing follicles at any time. Expression of mRNA encoding the cell death gene bax was reduced (p < 0.05) on d1 after 1× VCD in isolated primordial and primary follicles. These observations were in contrast to a decreased (p < 0.05) number of healthy primary and primordial follicles in ovaries and increased (p < 0.05) bax mRNA in isolated follicles from rats dosed 15× for 15 days. Immunofluorescence staining revealed that, the distribution of Bax protein was similar between ovaries from controls and 1× or 15× VCD-treated rats. These data provide evidence for a “protective” response against the normal rate of atresia in primary ovarian follicles following exposure to 1× VCD. Additionally, changes in expression of bax mRNA paralleled alterations in the rate of atresia.
Calculation of agonist efficacy, apparent affinity, and receptor population changes after administration of insurmountable antagonists: comparison of different analytical approaches.

Abstract The determination of the affinity and efficacy of an agonist in functional (as opposed to radioligand binding) experiments is necessary to explain its potency. Using modeled dose-response data both in their ideal form and with an added average deviation as well as previously published experimental data, a variety of analytical approaches were compared which differed in goodness-of-fit, ease of handling, and range of successful application. A nonlinear curve-fitting algorithm that analyzed several dose-response curves simultaneously and fitted them to an extended version of the operational model of Black and Leff (1983) (Proc R Soc Lond B 220: 141–162) was demonstrated to be superior to the other approaches using the above criteria. However, judging from the limitations of the analytical approaches, claims of efficacy or affinity differences between agonists that are based on less than 10-fold numerical differences in the same behavioral paradigm should be viewed with skepticism. It was also found that simple inspection of dose-response curves obtained before and after administration of an insurmountable antagonist give estimates of fair accuracy under most circumstances.
Numerical studies on an air-breathing proton exchange membrane (PEM) fuel cell stack

Air-breathing proton exchange membrane (PEM) fuel cells provide for fully or partially passive operation and have gained much interest in the past decade, as part of the efforts to reduce the system complexity. This paper presents a detailed physics-based numerical analysis of the transport and electrochemical phenomena involved in the operation of a stack consisting of an array of vertically oriented air-breathing fuel cells. A comprehensive two-dimensional, nonisothermal, multi-component numerical model with pressurized hydrogen supply at the anode and natural convection air supply at the cathode is developed and validated with experimental data. Systematic parametric studies are performed to investigate the effects of cell dimensions, inter-cell spacing and the gap between the array and the substrate on the performance of the stack. Temperature and species distributions and flow patterns are presented to elucidate the coupled multiphysics phenomena. The analysis is used to determine optimum stack designs based on constraints on desired performance and overall stack size.
CubeThat: news article recommender

The CubeThat browser extension for Chrome displays recommended additional news stories related to the same topic as the current news story. The recommended stories are organized into clusters, and clusters that the user has already sampled from are grayed out, in order to encourage users to explore multiple aspects of a story. Users can also provide feedback to improve the clustering, by dragging stories from one cluster to another.
PINCH-1 Is an Obligate Partner of Integrin-linked Kinase (ILK) Functioning in Cell Shape Modulation, Motility, and Survival

PINCH-1 is a widely expressed focal adhesion protein that forms a ternary complex with integrin-linked kinase (ILK) and CH-ILKBP/actopaxin/α-parvin (abbreviated as α-parvin herein). We have used RNA interference, a powerful approach of reverse genetics, to investigate the functions of PINCH-1 and ILK in human cells. We report here the following. First, PINCH-1 and ILK, but not α-parvin, are essential for prompt cell spreading and motility. Second, PINCH-1 and ILK, like α-parvin, are crucial for cell survival. Third, PINCH-1 and ILK are required for optimal activating phosphorylation of PKB/Akt, an important signaling intermediate of the survival pathway. Whereas depletion of ILK reduced Ser473 phosphorylation but not Thr308 phosphorylation of PKB/Akt, depletion of PINCH-1 reduced both the Ser473 and Thr308 phosphorylation of PKB/Akt. Fourth, PINCH-1 and ILK function in the survival pathway not only upstream but also downstream (or in parallel) of protein kinase B (PKB)/Akt. Fifth, PINCH-1, ILK and to a less extent α-parvin are mutually dependent in maintenance of their protein, but not mRNA, levels. The coordinated down-regulation of PINCH-1, ILK, and α-parvin proteins is mediated at least in part by proteasomes. Finally, increased expression of PINCH-2, an ILK-binding protein that is structurally related to PINCH-1, prevented the down-regulation of ILK and α-parvin induced by the loss of PINCH-1 but failed to restore the survival signaling or cell shape modulation. These results provide new insights into the functions of PINCH proteins in regulation of ILK and α-parvin and control of cell behavior.
Effectiveness of an eating disorder preventative intervention in primary care medical settings

Abstract Objective To conduct a pilot effectiveness trial of a brief dissonance-based eating disorder preventative program, the Body Project, when implemented at primary care medical clinics. Method Sixty-six female adolescents between the ages of 13 and 17 who reported at least some body image dissatisfaction were recruited at two primary care clinics and randomized to Body Project groups or an educational video control condition; eating disorder risk factors and symptoms were measured at pretest, posttest, and 3-month follow-up. Results Body Project versus educational video control participants showed significantly greater reductions in thin-ideal internalization, pressure to be thin, dieting, and eating disorder symptoms at posttest, which were medium to large effect sizes. Body Project participants also showed greater decreases in body dissatisfaction and negative affect at posttest, though these moderate sized effects were not significant. Effects persisted through 3-month follow-up. Conclusion Average pre–post effect sizes (d = 0.58) compare favorably to those observed in past Body Project efficacy (average d = 0.59) and effectiveness trials (average ds of 0.43 and 0.69), suggesting that primary care clinics may represent a novel venue for offering and extending the reach of this eating disorder prevention program.
Azimuth variation in microwave scatterometer and radiometer data over Antarctica

While designed for ocean observation, scatterometer and radiometer data have proven very useful in a variety of cryosphere studies. Over large regions of Antarctica, ice sheet and bedrock topography and the snow deposition, drift, and erosional environment combine to produce roughness on various scales. Roughness ranges from broad, basin-scale ice-sheet topography at /spl sim/100 km wavelengths to large, spatially coherent dune fields at /spl sim/10 km wavelength to erosional features on the meter scale known as sastrugi. These roughness scales influence the microwave backscattering and emission properties of the surface, combining to introduce azimuth-angle dependencies in the satellite observation data. In this paper, the authors explore the use of NASA scatterometer (NSCAT) data, European remote sensing (ERS) advanced microwave instrument (AMI) scatterometer mode data, and special sensor microwave/imager (SSM/I) data to study surface roughness effects in Antarctica. All three sensors provide strong evidence of azimuth modulation, which is correlated with the surface slope environment and results in a katabatic wind flow regime. Due to its broad azimuth coverage, NSCAT data appears to be the best suited for azimuth-angle observations. A simple empirical model for the azimuth variation in the radar backscatter is developed, and an algorithm for computing the parameters of the model from NSCAT data at a fine scale is presented. Results indicate relationships exist between the azimuthal variation of the data and the orientation of the surface slope and small-scale roughness relative to the sensor-look direction.
Quantifying the operational status of the DNSSEC deployment

This paper examines the deployment of the DNS Security Extensions (DNSSEC), which adds cryptographic protection to DNS, one of the core components in the Internet infrastructure. We analyze the data collected from the initial DNSSEC deployment which started over 2 years ago, and identify three critical metrics to gauge the deployment: availability, verifiability, and validity. Our results provide the first comprehensive look at DNSSEC's deployment and reveal a number of challenges that were not anticipated in the design but have become evident in the deployment. First, obstacles such as middle-boxes (firewalls, NATs, etc.) that exist in today's Internet infrastructure have proven to be problematic and have resulted in unforeseen availability problems. Second, the public-key delegation system of DNSSEC has not evolved as it was hoped and it currently leaves over 97% of DNSSEC zones isolated and unverifiable, unless some external key authentication mechanism is added. Furthermore, our results show that cryptographic verification is not equivalent to validation; a piece of verified data can still contain the wrong value. Finally, our results demonstrate the essential role of monitoring and measurement in the DNSSEC deployment. We believe that the observations and lessons from the DNSSEC deployment can provide insights into measuring future Internet-scale cryptographic systems.
Lifetime Model for Advanced N-Channel Transistor Hot-Carrier-Injection Degradation

A hot-carrier-injection (HCI) lifetime model of high-voltage (HV) N-channel transistors based on physical and mathematical basis is proposed. HV N-channel transistors show two peak values in the substrate-current-gate-voltage curve due to two high-electric-field regions (THFRs). The THFRs of HV transistors are found to be responsible for two coexistent HCI degradation mechanisms-interface trap generation and hole injection. The HCI lifetime model is modified based on the combined degradation mechanisms and updated substrate current model in HV N-channel transistors.
Origin and development of tafoni in Tunnel Spring Tuff, Crystal Peak, Utah, USA

Bedding-parallel tafoni are well developed over much of the surface of the Tunnel Spring Tuff (Oligocene) exposed in 300-m-high Crystal Peak, an inselberg. The Tunnel Spring Tuff is a crudely stratified, non-welded rhyolite ash-flow tuff with > 30 per cent porosity. Clasts of Palaeozoic dolomite, limestone and quartzite make up 10 per cent of the tuff. The tafoni are remarkable because of their size (up to 20 m wide but rarely wider than 4 m), shape of the openings (spherical, arch-like or crescent-shaped) and abundance (up to 50 per cent of an outcrop face). They are actively forming today. Calcite is abundant (10 to 40 per cent by weight) in tafoni as an efflorescence in spalling flakes of tuff on their roofs and walls. Halite and gypsum generally make up less than 0·01 per cent of the efflorescence. The absence of corroded quartz and feldspar grains in spall fragments indicates that chemical weathering is unimportant in development of the tafoni. Calcite, aragonite, halite and gypsum dust from modern salt pans less than 20 km from Crystal Peak are potential sources of salt in the tuff, but the prevailing winds are in the wrong direction for significant amounts of these evaporite minerals to reach the inselberg. Calcite is the only evaporite mineral present in the tafoni in more than trace amounts, and this mineral is readily available within the tuff itself as a result of rock weathering. We propose that meteoric water containing carbonic acid infiltrates the tuff, dissolves carbonate clasts, and migrates to the steep flanks (>20°) of the peak through abundant megapores and micropores. There it evaporates and precipitates calcite. Crystallization pressure spalls off grains and sheets as the physical manifestation of salt weathering. The quasi-uniform spacing of tafoni suggests that a self-organization process is active in the water flow. Copyright © 2000 John Wiley & Sons, Ltd.