cssi/SciSciGPT-SciSciNet huggingface dataset:
Wet deposition from clouds and precipitation in three high-elevation regions of the Eastern United States

Abstract Three regions are identified in the Eastern United States (US) that contain substantial land area at high elevations: the mid-Appalachian region (MAR), Eastern New York state (ENY), and the New England region (NER). Approximately 75% of the land cover in these areas is forested, with 5.6–29% of the total acreage above 600 m and subject to cloud deposition. Measurements of cloud deposition are scarce. A 6-year data record of measurements at two high-elevation locations is considered, and scaling factors are developed to enable the rough estimation of area-wide cloud deposition at various elevations in each region. Estimates of precipitation and associated ion deposition are made at 12 arc-second resolution for the Eastern US and are used to obtain elevation-resolved precipitation-mediated deposition for the three study regions. At high elevations, clouds account for a substantial proportion of wet deposition (i.e., the sum of that from clouds and precipitation). For the total land area above 600 m , clouds may account for 20–60% of the total wet ion deposition, with the exact proportion depending on both location and ion species. At elevations above 600 m , but below the climatic tree line, the ratio of cloud-to-precipitation-mediated deposition is higher in NER and ENY than in MAR. At the highest elevations of each study region, clouds may account for over 80% of the wet ion deposition. Although the wet deposition of ammonium (NH4+), sulfate (SO42−), nitrate (NO3−), and hydrogen (H+) ions is enhanced at higher elevations by clouds over precipitation, this enhancement is the largest for ammonium. This study illustrates the major and perhaps dominant role that clouds may play by delivering considerable ion loads to montane ecosystems in selected elevation ranges where these ecosystems may be especially vulnerable.
Sensitivity of pathway rate to activities of substrate-cycle enzymes: application to gluconeogenesis and glycolysis

In a study of metabolic regulation, it is frequently useful to consider the degree to which an enzyme can influence the rate of its pathway. The most productive expression of rate-controlling influence is the fractional change in pathway rate per fractional change in enzyme activity (called control strength or sensitivity coefficient). We have developed a system for considering how a substrate-cycle enzyme's control strength depends on its flux and reaction order and on related features of other enzymes of its pathway. We have applied this system to the gluconeogenic pathway of rat liver and the glycolytic pathway of bovine sperm, where enough fluxes and reaction orders have been published to allow valid estimates of several control strengths. In normal fed animals where gluconeogenesis is slow and unidirectional substrate-to-product and product-to-substrate fluxes are comparable, all substrate-cycle limbs have very high and similar control strengths regardless of their flux rates and positions in the pathway. The activity of a step affects all substrate-cycle control strengths similarly as it affects unidirectional end-to-end fluxes relative to net rate. Control strengths of non-substrate-cycle enzymes are negligible compared to those of substrate cycles. In fasting animals, on the other hand, where unidirectional Pyr----Glc flux is much greater than Glc----Pyr flux, upstream enzymes (near Pyr) have a regulatory advantage over downstream enzymes (near Glc). In this circumstance, control strength of each substrate-cycle enzyme is inversely related to rate limitingness between its substrate and the pathway substrate. Because the Pyr/PEP cycle is significantly rate limiting, the control strength of the Pyr----PEP limb is much greater than that of pyruvate kinase and all downstream enzymes. In the glycolytic pathway of bovine sperm, strong product inhibition of hexokinase detracts greatly from its rate limitingness and control strength, which are very small despite its position at the beginning of the pathway and its large free energy. Because the glucose-transport-hexokinase segment is not rate limiting, phosphofructo 1-kinase has almost as much control strength as it would have as the first enzyme of the pathway, and because the F6P/FDP cycle is only moderately rate limiting, Fru-1,6-P2ase and enzymes further downstream have substantial control strengths. When glycolysis is accelerated by stimulation of phosphofructo 1-kinase, control strength shifts from phosphofructo-1-kinase and all downstream enzymes to the transporthesokinase segment.(ABSTRACT TRUNCATED AT 400 WORDS)
A comparative study of root coverage with connective tissue and platelet concentrate grafts: 8-month results.

Background: Gingival recession presents destruction of both soft and hard tissues. The objectives of this randomized clinical trial were to assess the clinical efficacy of platelet concentrate grafts (PCG) in the treatment of Miller Class I or II buccal gingival defects and to compare their soft tissue healing with those of subepithelial connective tissue grafts (SCTG). Methods: Seventeen arches in 15 patients with bilateral gingival recessions were treated with SCTG and PCG covered by coronally advanced flaps. Vertical recession depth (VRD), clinical attachment level (CAL), clinical probing depth (PD), and width of keratinized tissue (KTW) were measured preoperatively and 8 months postsurgery. Surveys on post-surgical discomfort level (PSDL) and manual platelet count were also performed. Esthetic outcomes were also evaluated. Paired t test, repeated measures analysis of variance (ANOVA), and chi-square and signed-rank tests were used to access statistical significance (α = 0.05). Results: Mean VRD statis...
The interfacial dynamics of water sandwiched between graphene sheets are governed by the slit width

Atomic scale characterization and fluxional properties of water molecules in the vicinity of the graphene interface is carried out using molecular dynamics (MD) simulations. The structural properties of proximal water molecules near the graphene interface are strongly correlated to their vibrational densities of states while being studied as a function of the slit width of the graphene sheets. Our simulations indicate that the local orientation, ordering and solvation dynamics of interfacial water molecules are a strong function of the graphene slit width. Systematic trends in libration, bending, and stretching bands are correlated with local ordering of water molecules and hydrogen-bonding network. Smaller blue shifts in the intermolecular O…O…O bending mode and larger blue shifts in the O…O intermolecular stretching modes of water molecules are observed for strongly confined water molecules in comparison to bulk water, which is attributed to the interfacial proximity effects resulting in the restricted transverse oscillations of confined water. The O―H stretching band is red-shifted for confined water in comparison to bulk water whereas the libration and bending bands for interfacial water are blue shifted with respect to bulk water. The observed frequency shifts are a consequence of the distortion of the tetrahedral order in confined water caused by lateral diffusion being reduced and also by changes in the distribution of hydrogen bonds. These simulations suggest that the extent of the shifts of confined water in comparison to bulk water are due to the proximity from the hydrophobic surface, their local confinement and hydrogen bonding status.
Nitrate Losses from Disturbed Ecosystems

A systematic examination of nitrogen cycling in disturbed forest ecosystems demonstrates that eight processes, operating at three stages in the nitrogen cycle, could delay or prevent solution losses of nitrate from disturbed forests. An experimental and comparative study of nitrate losses from trenched plots in 19 forest sites throughout the United States suggests that four of these processes (nitrogen uptake by regrowing vegetation, nitrogen immobilization, lags in nitrification, and a lack of water for nitrate transport) are the most important in practice. The net effect of all of these processes except uptake by regrowing vegetation is insufficient to prevent or delay losses from relatively fertile sites, and hence such sites have the potential for very high nitrate losses following disturbance.
Psychodynamics of Coping and Survival of the African-American Female in a Changing World.

Scientific breakthroughs, technological advances, and the overall, rapid pace of modern urban life are the hallmarks of the present century. The highest standard of living in the world has not been achieved without cost. African-Americans, historically isolated from the mainstream, have been unable to resist the allure of this momentum that surges forth into the 21st century. AfricanAmericans can be considered more spectators than true participants in the technological renaissance. That is, the objective conditions of life confronting the majority of persons of African ancestry are still predominately those of poverty, limited employment, thwarted educational opportunities, discrimination, and overt/covert acts of racism. Some individual African-Americans have benefited from employment opportunities in professions formerly not available to their predecessors. Swinton (1988: 130) states that "in fact, there has been an increase in proportion of African-Americans who can be classified as upper middle class." Yet no people have ever been judged by the condition of its exceptions. Although an AfricanAmerican's median income has increased in absolute dollars since 1970 (with the exception of 1982), the startling reality is one where "average median black income for the 1990's is only $16,476 as compared to $17,765 for the 1970's" (Swinton, 1988: 132). Another
Delayed gastric perforation resulting from hydrochloric acid ingestion.

1All authors: Department of Radiology, Harborview Medical Center, University of Washington School of Medicine, 325 Ninth Ave., Box 359728, Seattle, WA 981042499. Address correspondence to F. A. Mann (famann@u.washington.edu). Case Report A 29-year-old man with schizophrenia presented to the emergency department with abdominal pain immediately after ingesting approximately 200 mL of cleaning solution containing 36% hydrochloric acid. Initial unenhanced CT of the chest, abdomen, and pelvis showed an intact stomach and a small amount of free intraperitoneal fluid (Fig. 1A). Direct endoscopy showed mucosal injury in the oropharynx, hypopharynx, and supraglottic region, and diffuse caustic injury to the esophageal mucosa. Because of worsening clinical status, a contrast-enhanced CT of the abdomen was performed 2 days later, showing gastric necrosis and perforation (Fig. 1B). The patient died shortly thereafter.
The design of function generators using short-time memory devices and nonlinear elements

The analog computer field is frequently concerned with the generation of periodic nonsinusoidal functions of time. At present this waveform generation is frequently performed with biased diode networks, curve followers, and synchronous switches. The main purpose of this paper is to give the theoretical design and analysis of nonsinusoidal function generators which utilize delay-type or short-time memory devices and certain nonlinear elements in their structure. The different types of function generators to be discussed have the common property that the output waveform may be controlled easily and may be made to approximate various desired shapes to high degrees of accuracy.
Infrared (10.6-μm) radiation induced evaporation of large water drops

The evaporation rate of water drops (~1.0–2.5-mm diameter) suspended in a CO2 laser beam has been measured using an optical technique involving fixed-angle forward-scattering observations of the expanding diffraction pattern. The results show a dr/dt ≈ 1.6-μm-sec−1 increase over the natural evaporation rate that is due to the internal particle heating produced by 10.6-μm energy absorption at an irradiance of ~1.65 W cm−2. Drop temperature records and dr/dt fluctuations over 30-μm-radius increments indicate a quasi-steady-state evaporation process in which free convection and internal drop circulation are important temperature-regulating mechanisms.
Reinitiation of an arrested cleavage crack

Abstract Transverse-wedge-loaded compact specimens were used to measure the fracture toughness associated with reinitiation of an arrested cleavage crack. The data are consistent with more conventional measurements as well as large-cylinder thermal-shock results. It is suggested that this procedure can provide single-specimen crack-initiation and crack-arrest toughness.
Fractionation and subcellular localization of marker enzymes in rainbow trout liver

Abstract The subcellular fractionation of rainbow trout liver homogenates prepared in 0.25 M sucrose was investigated using marker enzymes to assess the homogeneity of the resulting fractions. In addition to the usual mitochondrial and microsomal fractions, an additional fraction was sedimented between 8000 g for 10 min and 13,300 g for 10 min. Of the four accepted hydrolytic “marker” enzymes for rat liver lysosomes, the high relative specific activity (R.S.A.) of acid phosphatase was indicative of enrichment in this fraction. The R.S.A. patterns of 5'-nucleotidase and alkaline phosphatase indicated that the plasma membranes of fish liver were sedimenting with “nuclear” and microsomal pellets. This latter fraction contained the highest percentage of the total glucose 6-phosphatase, benzopyrene hydroxylase and glucuronyl transferase assayed in the fish liver homogenate before fractionation. The R.S.A. of these same enzymes in the microsomal pellet indicated an enrichment in this fraction relative to other cellular fractions.
Inelastic collisions between selectively excited rubidium atoms and ground-state rubidium atoms

Inelastic-collision processes in fine-structure-changing collisions have been studied by selective stepwise excitation and observation of the resulting fluorescence. Hereby, the effect of ground-state rubidium atoms colliding with excited-state rubidium atoms was investigated. The ground-state density was changed by three orders of magnitude by performing the measurements over the temperature range of 75 to 200 /sup 0/C. The cross section for fine-structure-changing collisions (i.e., Rb(6/sup 2/D/sub 5/2/)+Rb(5/sup 2/S/sub 1/2/)..-->..Rb(6/sup 2/D/sub 3/2/) + Rb(5/sup 2/S/sub 1/2/)) is sigma/sub fs/ = (1.0 +- 0.6) x 10/sup -13/ cm/sup 2/. The cross sections for transfer out of the fine-structure doublet (i.e., Rb(6/sup 2/D)+Rb(5/sup 2/S/sub 1/2/)..-->.. states other than Rb(6/sup 2/D)) is sigma/sub tr/ = (3.8 +- 0.6) x 10/sup -13/ cm/sup 2/. It is demonstrated that for the intermediate excited rubidium states, both the fine-structure-changing and transfer cross sections are of the order of the geometrical cross section of the excited rubidium states.
Epidermal growth factor induces rapid tyrosine phosphorylation of proteins in A431 human tumor cells

Addition of EGF to A431 cells at physiological concentrations causes a rapid three- to four-fold increase in the abundance of phosphotyrosine in cellular protein. The increase is essentially complete within 1 min and is maintained for several hours. No change in phosphotyrosine levels is found with fibroblast growth factor or insulin. Two phosphoproteins (molecular weights of 39 and 81 kd) containing phosphotyrosine appear de novo upon administration of EGF to A431 cells. The EGF receptor itself is a phosphoprotein containing phosphotyrosine as well as phosphoserine and phosphothreonine. Changes in the phosphorylation pattern of the EGF receptor are seen upon treatment of A431 cells with EGF. Increased phosphorylation of tyrosine is the most rapid response of cells to EGF known, and may play an important role in the biological effects of EGF.
Neurosecretory system of the American dog tick, Dermacentor variabilis (Acari: lxodidae). I. Diversity of cell types.

An arbitrary classification scheme is presented for the thirteen distinct types of secretory cells distinguished within the central nervous system of Dermacentor variabilis by several specific and general neurosecretory staining techniques. Comparisons to classic arthropod neurosecretory cell types are made and the histochemical implications of the chromophilic response of various secretory products are discussed. Dermacentor cells of Types I, VII, IX and X may be considered neurosecretory on the basis of intracellular elaboration and discharge of secretory product. Type II, III, IV, V, VI, XI and XII cells are considered as putative neurosecretory cells although secretory products were detected only within the perikarya. The large Type XII cells are also similar to motor neurones reported from other arachnids. Cells of Types VIII and XIII appear to be glial elements. The secretory products of Type XIIIA are distributed within trabecular processes in the subperineurium. These products may play a trophic role or they may have some endocrine function as a form of "gliosecretion".
THE EFFECT OF PROPHYLACTIC SURFACTANT vs SURFACTANT TREATMENT OF ESTABLISHED RESPIRATORY DISTRESS SYNDROME: UPDATED OVERVIEW. † 1595

Seven randomized controlled trials comparing prophylactic administration of natural surfactant extract to natural surfactant extract treatment of established Respiratory Distress Syndrome (RDS) have been reported. These 7 trials enrolled 2455 infants. Six of the studies enrolled infants less than 30 weeks gestation exclusively; one study enrolled infants 29-32 weeks gestation. Infants were given either prophylactic surfactant at birth or surfactant treatment if assisted ventilation was required and parenchymal lung disease was noted. Infants who received prophylactic surfactant were treated within 10 minutes of birth. The average time of treatment in the selective treatment group varied from 1.5 to greater than 6 hours. The results of the meta-analysis are given below: Table Prophylactic administration of surfactant leads to a decreased risk of pneumothorax and mortality. No differences in the risk of other neonatal complications are noted. Improved identification of high risk infants could lead to even greater efficacy of prophylactic therapy. Cochrane Neonatal Review Group sponsored by NIH Contract NO1-6-3252.
Eicosanoids mediate nodulation responses to bacterial infections in larvae of the tenebrionid beetle, Zophobas atratus

Abstract Nodulation is the temporally and quantitatively predominant cellular defense response to bacterial infection in insects and other invertebrates. Inhibition of eicosanoid biosynthesis in larvae of the tenebrionid beetle, Zophobas atratus, immediately prior to intrahemocoelic injections with heat killed preparations of the bacterium, Serratia marcescens, strongly reduced the nodulation response. Separate treatments with specific inhibitors of phospholipase A2, cyclooxygenase, and lipoxygenase reduced nodulation, supporting the view that nodule formation is a complex process involving both cyclooxygenase and lipoxygenase products. The inhibitory effects of the phospholipase A2 inhibitor, dexamethasone, on nodulation were apparent 1 h after infection, and the effects increased, relative to controls, over 24 h. The dexamethasone effects were expressed in a dose-dependent manner, and they were reversed by treating bacteria injected insects with the eicosanoid-precursor polyunsaturated fatty acid, arachidonic acid (C20:4n-6). Treatments with the saturated fatty acid, 16:0, which is not an eicosanoid precursor, did not reverse the dexamethasone effects on nodulation. The insects contain low levels of three eicosanoid precursor polyunsaturated fatty acids in six different tissues, and fat body preparations are competent to produce both cyclooxygenase and lipoxygenase products. These findings strongly support the identification of nodulation as a specific insect cellular defense mechanism that is mediated by eicosanoids.
Cytochrome P450 reductase-mediated anaerobic biotransformation of ethanol to 1-hydroxyethyl-free radicals and acetaldehyde

The ability of cytochrome P450 reductase to metabolize ethanol (EtOH) to acetaldehyde (AC) and 1-hydroxyethyl free radicals (1HEt) in anaerobic media was studied. Determination of AC was made by GC-FID analysis of the head space of incubation mixtures. The formation of 1HEt was established by GC-MS analysis of the adduct formed between the radical and the spin trap PBN. Results showed that pure human P450 reductase is able to biotransform EtOH to AC and 1HEt in a NADPH-dependent process under an oxygen-free nitrogen atmosphere. Pure FAD in the presence of NADPH was also able to generate AC and 1HEt from the alcohol. Anaerobic incubation mixtures containing either rat liver microsomes or pure nuclei were also able to biotransform EtOH to AC and 1HEt in the presence of NADPH. These processes were inhibited by antibody against rat liver microsomal P450 reductase. Results suggest that semiquinone forms of the flavin in P450 reductase may biotransform EtOH. These reactions might be of some significance in tissues where the P450 reductase is present in the absence of specific forms of cytochrome P450 known to be involved in EtOH metabolism (e.g. CYP2E1). However the toxicological significance of this enzymatic process remains to be established.
ϕ-Value Analysis for Ultrafast Folding Proteins by NMR Relaxation Dispersion

Proteins that fold rapidly, on the (sub-) microsecond time scale, offer the prospect of direct comparison between experimental data and molecular dynamics simulations. However, experimental studies for such proteins frequently are hindered because folding rates are too fast to measure using conventional stopped-flow methods. To overcome this impediment, NMR spin relaxation dispersion experiments are used to quantify mutational effects on kinetics (ΔΔG°), stability (ΔΔG°), and ϕ-values (ΔΔG†/ΔΔG°) for proteins exhibiting chemical exchange line broadening that is fast on the NMR chemical shift time scale. The accuracy of ϕ-value analysis is enhanced because mutational effects on denatured or intermediate states can be detected through changes in line broadening. The transition and intermediate states of the villin headpiece domain, HP67, are characterized in varying solvent conditions to validate the method.
Acetaldehyde scavengers and their effects on thermal stability and physical properties of poly(ethylene terephthalate)

The acetaldehyde (AA) scavenging abilities of poly(ethylene terephthalate) (PET) blends containing various concentrations of anthranilamide, meta-xylenediamine (MXDA), or alpha-cyclodextrin have been evaluated. It was found that higher AA scavenger concentrations generally resulted in greater reductions in detectable AA in terms of both the AA generation rates and residual AA contents. As little as 100 ppm, by weight, of anthranilamide and MXDA were respectively shown to reduce residual AA detected in PET preforms by 46% and 36%. Melt-blending 500 ppm of alpha-cyclodextrin, into PET, reduced preform residual AA concentration by 42%. The scavengers acted as PET nucleating agents causing more rapid crystallization while heating the blends from the glassy state and when cooling from the melt; however, they caused no changes in the glass transitions, melting characteristics, or oxygen permeation behaviors of the blends. Addition of optimal scavenger concentrations had minimal effects on preform intrinsic viscosity and color changes. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Investigating the distance limit of a metal nanoparticle based spectroscopic ruler

Conventional Forster resonance energy transfer (FRET) processes involving a pair of fluorophore and organic quencher are restricted to an upper distance limit of ~10 nm. The application of a metal nanoparticle as a quencher can overcome the distance barrier of the traditional FRET technique. However, no standard distance dependence of this resonance energy transfer (RET) process has been firmly established. We have investigated the nonradiative energy transfer process between an organic donor (fluorescein) and gold nanoparticle quencher connected by double stranded (ds) DNA. The quenching efficiency of the gold nanoparticle as a function of distance between the donor and acceptor was determined by time-resolved lifetime analyses of the donor. Our results showed a 1/d4 distance dependence for the RET process for longer distances (>10 nm) and 1/d6 distance dependence for shorter distances (<10 nm). Our results clearly indicate the applicability of metal nanoparticle based quenchers for studying systems that exceed the 10 nm FRET barrier.
Procedure for building a consistent embedding at the QM–CM interface

We propose and test a method for a consistent embedding of a domain treated with detailed quantum mechanical methods (QM) inside a domain treated using classical mechanical (CM) potentials. The physical context of this embedding is the response of a system to mechanical strain which leads to fracture. To provide a quantitative test of qualitative ideas, a model system capable of being treated by QM in its entirety is chosen: a silica nano-rod, comprised of 108 atoms. The embedding is constructed so that the CM description yields the same linear response to mechanical strain as the QM description to within a few percent. An acceptable composite representation of the full system requires (1) a CM potential for the classical domain with appropriate linear mechanical response, (2) pseudo-atoms for the termination of dangling bonds at the QM/CM interface, and (3) a dipole description for the polarization of the remainder of the CM region. A key test for the fidelity of the modeled QM domain is accurate forces and electronic charge densities. We show that the composite has the small strain behavior of the full QM treatment of the nano-rod. We find similar success in the application of this method to two other silica model systems: the notched rod, and a nano-ring. Both transfer Hamiltonian (TH) and density functional theory (DFT) are used for the underlying QM.
The neuroscience of memory: implications for the courtroom

Psychology and neuroscience studies have shown that memory is a reconstructive process that is susceptible to distortion. Lacy and Stark summarize the evidence and discuss how this insight could be applied to police and courtroom procedures.
Design and modeling of chemical vapor deposition reactors

Abstract The performance of chemical vapor deposition (CVD) reactors is strongly dependent on fluid flow, heat transport and mass transport. The optimized design of CVD reactors requires an understanding of how these phenomena influence the uniformity in growth rate, composition, and doping. This article will review recent developments in the study of CVD reactors. The focus will be on understanding how the interplay of physical properties and reactor geometries influences fluid flow and growth uniformity. Both numerical models and flow visualization studies of transport phenomena are reviewed. Despite the considerable power of these computational and experimental tools, the greatest asset in reactor design is the ability to conceptualize the interplay and relative significance of different transport phenomena. With this in mind, the underlying goal of this review is to provide a conceptual framework of the fundamental transport phenomena at work in CVD reactors, the conditions under which each of these phenomena plays a roll, and their combined impact on reactor design.
Opposing interactions of ionophores (valinomycin and monensin) on calcium ion uptake in rat retinal preparations

Valinomycin is a potent inhibitor of taurine-stimulated ATP-dependent calcium ion uptake in rat retinal membrane preparations but had no effect on ATP-dependent calcium ion uptake in the absence of taurine and no effect on ATP-independent calcium ion uptake. The presence of potassium ions in the buffer systems were required for valinomycin to be inhibitory. On the contrary, monensin stimulated calcium ion uptake in the ATP-dependent system but had no effect on ATP-independent calcium ion uptake. The crude retinal homogenate was also fractionated into various subcellular components. The fraction which contained photoreceptor cell synaptosomes (P1) had a higher, specific activity for taurinestimulated ATP-dependent calcium ion uptake than the crude homogenate or either the fractions which contained synaptosomes derived from the plexiform layer (P2) or rod outer segments (ROS). No differences in calcium ion uptake were observed in the various subcellular fractions compared to the homogenate when assayed for ATP-dependent calcium ion uptake. Valinomucin inhibited both ATP-dependent and taurine-stimulated ATP-dependent calcium ion uptake in the P1, P2, and ROS fractions while monensin stimulated the ATP-dependent calcium ion uptake in the subcellular fractions.
Evolution of Laboratory Parameters During Sickle Cell Painful Crisis: Evidence Compatible with Dense Red Cell Sequestration Without Thrombosis

We find that during 51 episodes of sickle cell painful crisis indirect bilirubin fell 52% from its steady state value of 2.3 ± 1.9 mg% to a value of 1.1 ± 0.37 mg% at the end of crisis (p <.00000085). The indirect bilirubin decline correlates with a decrease in the dense sickle cells during crisis (r = .31, p <.0009). During steady state, both indirect bilirubin and lactic acid dehydrogenase correlate significantly with number of dense red cells (r = .62, p < .000002 and r = .32, p < .02 respectively). Platelet counts, β-thromboglobulin, Platelet Factor 4, and Fibrinopeptide A levels all were elevated during steady state and did not change during the evolution of crisis. These data demonstrate that elevated indices usually associated with platelet activation are a feature of the steady state of sickle cell disease but argue against thrombosis as a factor in the progression of a sickle cell painful crisis episode. The parallel decline of both dense cells and bilirubin during painful crises indicates that the disappearance of dense cells during crisis is not caused by hemolysis and supports the hypothesis that dense red cell sequestration, in the absence of evidence of thrombosis, is an intrinsic component of the evolution of sickle cell painful crisis.
Caspase-3-like proteases and 6-hydroxydopamine induced neuronal cell death.

Neurotoxicity induced by 6-hydroxydopamine (6-OHDA) is believed to be due, in part, to the production of reactive oxygen species (ROS) and/or an inhibition of mitochondrial function. However, little is known about the ensuing intracellular events which ultimately result in cell death. Here we show that exposure to relatively low concentrations of 6-OHDA induces apoptosis of cerebellar granule neurons (CGN). 6-OHDA-induced apoptosis of CGN is associated with activation of a caspase-3-like protease. Western blots of cytosolic extracts from 6-OHDA-treated CGN reveal a translocation of cytochrome c from mitochondria to the cytosol, which precedes activation of the protease detected by Ac-DEVD-pNA. DNA laddering can be blocked by caspase inhibitors zVAD-FMK and Ac-DEVD-CHO, however cell death can only be attenuated for a short time period in the presence of these inhibitors. Our data suggest that 6-OHDA-induced apoptosis of CGN involves activation of a caspase-3-like protease. In contrast to the neurotoxicity induced by MPP+, however, the peptide inhibitors zVAD-FMK and Ac-DEVD-CHO can only attenuate early neuronal death induced by 6-OHDA. At later time points, neuronal death lacking DNA laddering occurs even in the presence of the peptide inhibitor zVAD-FMK or Ac-DEVD-CHO.
Analysis and control of a hybrid fuel delivery system for a polymer electrolyte membrane fuel cell

Abstract A polymer electrolyte membrane fuel cell (PEM FC) system as a power source used in mobile applications should be able to produce electric power continuously and dynamically to meet the demand of the driver by consuming the fuel, hydrogen. The hydrogen stored in the tank is supplied to the anode of the stack by a fuel delivery system (FDS) that is comprised of supply and recirculation lines controlled by different actuators. Design of such a system and its operation should take into account several aspects, particularly efficient fuel usage and safe operation of the stack. The exiting unconsumed hydrogen is circulated and reused to increase the efficiency and at the same time maintain the humidity in the anode side of the stack, thereby preventing drying and flooding in the channel which can affect the stack performance. A high pressure difference across a cell between the anode and cathode could cause damage on thin layers of the cell components and water imbalance in the membranes. In this paper, we analyze a hybrid fuel delivery system that consists of two supply and two recirculation lines. The major components were a pressure regulator, a flow control valve, an ejector, and a blower. These models were developed and connected in order to analyze dynamic behavior of the fuel delivery system. Based on the models, two control strategies, a decentralized classic proportional and integral control and a state feed-back control were designed and optimized to keep a constant pressure in the anode flow channel and a constant ratio of mass flow rates from recirculation to supply lines. The integrated system with the two different controllers was simulated to evaluate its tracking and rejection performance at different references and disturbances.
The mediating role of parenting in the associations between household chaos and children’s representations of family dysfunction

Children’s drawings are thought to reflect their mental representations of self and their interpersonal relations within families. Household chaos is believed to disrupt key proximal processes related to optimal development. The present study examines the mediating role of parenting behaviors in the relations between two measures of household chaos, instability and disorganization, and how they may be evidenced in children’s representations of family dysfunction as derived from their drawings. The sample (N = 962) is from a longitudinal study of rural poverty exploring the ways in which child, family, and contextual factors shape development over time. Findings reveal that, after controlling for numerous factors including child and primary caregiver covariates, there were significant indirect effects from cumulative family disorganization, but not cumulative family instability, on children’s representation of family dysfunction through parenting behaviors. Results suggest that the proximal effects of dail...
Social Security Claimants with Developmental Disabilities - Problems of Policy and Practice

This article, which is a contribution to a symposium in the Kansas Law Review on Developmental Disabilities and the Law, argues that broad policy changes within the Social Security Administration (SSA) have exacerbated the inherent practical difficulties confronted by claimants with developmental disabilities when dealing with the Social Security Bureaucracy. In particular, the SSA has come increasingly to emphasize its limited resources and responsibility for conserving those resources, resulting in a tightening of standards, insistence on objective evidence of disabilities and their impact on a claimant’s ability to work, and pressure on decisionmakers throughout the administrative hierarchy to deny benefits in doubtful cases. While these forces have adversely affected claimants in general, claimants with developmental disabilities are especially vulnerable. The article argues that while the resource problems plaguing disability programs are real, a bureaucratically imposed series of policies that fall most heavily on those least able to protect themselves is not an appropriate response. It is also hoped that a careful examination of the issues surrounding claims based on developmental disabilities will help practitioners overcome some of the bureaucratic obstacles they must address.The article begins with a general discussion of various policies and practices adopted by SSA during the 1980s that reflected a shift in focus toward increasing productivity of disability decisionmakers, securing adjudicatory consistency, and reducing erroneous awards of benefits. The article then considers the tightening of substantive standards and SSA’s increasing demands for objectively verifiable proof of disability, and considers how those changes led to changes in substantive standards and their application that make it increasingly difficult to establish eligibility for benefits based on a developmental disability. The article then turns to the procedural apparatus used to process benefit claims, arguing that it is vulnerable to a systemic anti-claimant bias and that various procedural obstacles may be especially difficult for claimants with developmental disabilities to overcome. Finally, the article considers the broader policy implications of these substantive and procedural issues.
Analysis of pseudo-interleaving AWG

Testing of a read channel for hard disk drives (HDD) requires an extremely high-speed arbitrary waveform generator (AWG) to emulate Lorentzian waveforms for read functional tests. If a sampling rate required to the AWG exceeds the maximum available rate of the instrument, a possible solution is to use two AWG's together running at the same rate synchronously and generating signal alternately to make their equivalent sampling rate doubled. One of the key components of such interleaving AWG is a high-speed analog selector. However it is not easy to find a good selector in ultra high frequency range. An application note proposes a practical solution that is a pseudo interleaving AWG. It is a variation of traditional signal combining method using a power combiner instead of a high-speed selector. This paper describes about performance analysis and experimental results of the pseudo interleaving compared to a true interleaving. Data stored in two AWG's are created with the same method as the true interleaving AWG. The data are simply distributed alternately into each AWG. The results show that the pseudo interleaving works well in spite of its simple structure and can be useful for generating Lorentzian waveforms
Redox signaling and splicing dependent change in myosin phosphatase underlie early versus late changes in NO vasodilator reserve in a mouse LPS model of sepsis.

Microcirculatory dysfunction may cause tissue malperfusion and progression to organ failure in the later stages of sepsis, but the role of smooth muscle contractile dysfunction is uncertain. Mice w...
Polyunsaturated Fatty Acids and Bovine Interferon-τ Modify Phorbol Ester-Induced Secretion of Prostaglandin F2α and Expression of Prostaglandin Endoperoxide Synthase-2 and Phospholipase-A2 in Bovine Endometrial Cells

Embryonic mortality in cattle may occur because of inadequate inhibition of uterine secretion of prostaglandin (PG) F2a mediated by bovine interferon-t (bIFN-t). The objectives of the present study were to determine whether polyunsaturated fatty acids inhibit secretion of PGF2a from bovine endometrial cells induced by stimulating protein kinase C with phorbol 12,13 dibutyrate (PDBu) and to investigate possible mechanisms of action. Confluent cells were exposed for 24 h to 100 mM of linoleic, arachidonic (AA; C20:4, n-6), linolenic (LNA; C18:3, n-3), eicosapentaenoic (EPA; C20:5, n-3), or docosahexaenoic (DHA; C22:6, n-3) acid. After incubation, cells were washed and stimulated with PDBu. The EPA, DHA, and LNA attenuated secretion of PGF2a in response to PDBu. The EPA and DHA were more potent inhibitors than LNA. The EPA inhibited secretion of PGF2a at 6.25 mM. Secretion of PGF2a in response to PDBu decreased with increasing incubation time with EPA. Both bIFN-t and EPA inhibited secretion of PGF2a, and their inhibitory effects were additive. The bIFN-t, but not EPA, reduced the abundance of PG endoperoxide synthase-2 (PGHS-2) mRNA. Incubation with 100 mM EPA, DHA, or AA for 24 h followed by treatment with PDBu did not affect concentrations of PGHS-2 and phospholipase A2 proteins. The EPA and DHA inhibit secretion of PGF2a through a mechanism different from that of bIFN-t. The effect of EPA on PGF2a secretion may be caused by competition with AA for PGHS-2 activity or reduction of PGHS-2 activity. The use of EPA and DHA to inhibit uterine secretion of PGF2a and to improve embryonic survival in cattle warrants further investigation. conceptus, cytokines, female reproductive tract, implantation, uterus
Role of development in the evolution of the scapula of the giant sthenurine kangaroos (Macropodidae: Sthenurinae)

Extinct giant sthenurine kangaroos possessed scapulae morphologically distinct from those of all other extant and extinct adult macropodids, but qualitatively resembling those of newborn macropodids. The similarity between adult sthenurine and neonatal macropodid scapulae suggests that a developmental process, such as heterochrony, might have been behind the evolution of the unique sthenurine scapular morphology. By incorporating adult and ontogenetic data, this study examines the evolution and development of the sthenurine scapula. This study quantitatively upholds the previous qualitative morphological observations of macropodid scapulae and finds that ontogenetic and evolutionary morphological changes are correlated in macropodids. The similarity of scapula morphology in sthenurines and newborn macropodids, the correlation between ontogenetic and evolutionary morphological change, and information from other sources (i.e., sthenurine evolutionary history) suggests that pedomorphic shifts in morphology, most likely due to neotenic processes, occurred within the development of the scapula of giant sthenurines. J. Morphol. © 2005 Wiley-Liss, Inc.
Additives used to limit systemic absorption

Abstract Use of local anesthetics is not without risk from systemic absorption. The amount absorbed is dependent on a variety of factors that include: the anesthetic itself, the location injected, volume, concentration, and additives with vasoconstrictive properties. Many agents with vasoconstrictive properties have been used to counteract the vasodilating properties of local anesthetics. Additives include epinephrine, phenylephrine, norepinephrine, levonordefrin, and felypressin, among others. Vasoconstrictors can decrease systemic blood levels of local anesthetics, prolong the duration of action of local anesthetics, act as a marker of intravascular injection, and increase the speed of onset of a block. Contraindications to the addition of vasoconstrictors include: unstable angina, uncontrolled hypertension, cardiac dysrhythmias, concomitant use of monoamine oxidase inhibitors or tricyclic antidepressants, peripheral nerve blocks in areas with end vessels, intravenous regional anesthesia, and situations where uteroplacental insufficiency may occur.
Factors influencing receptivity to future screening options for pancreatic cancer in those with and without pancreatic cancer family history.

Background Pancreatic cancer (PC) is considered the most lethal cancer and approximately 10% of PC is hereditary. The purpose of the study was to assess attitudes of at-risk family members with two or more relatives affected with pancreas cancer (PC) toward PC risk and future screening options.
Phosphorus, iron, and manganese distribution in sediment cores of six Wisconsin lakes1

Depositional patterns of iron, manganese, and phosphorus in one central and five northern Wisconsin lakes ranging from oligotrophic to eutrophic, primarily from natural causes, have been investigated. One-meter cores from one or more locations within each lake were analyzed. The historical pattern of iron and manganese deposition is closely related to the pattern of phosphorus deposition in most of the cores. Four of the nine cores show a strong positive correlation coefficient between P and Fe and seven between P and Mn. Manganese has more predictive value than iron for determining the concentration of phosphorus in a given core; however, the iron content appears to be the dominant factor in the phosphorus sorptive and retentive capacity of sediments.
Using Home Range Estimates To Construct Social Networks For Species With Indirect Behavioral Interactions

Social network analysis has become a vital tool for studying patterns of individual interactions that influence a variety of processes in behavior, ecology, and evolution. Taxa in which interactions are indirect or whose social behaviors are difficult to observe directly are being excluded from this rapidly expanding field. Here, we introduce a method that uses a probabilistic and spatially implicit technique for delineating social interactions. Kernel density estimators (KDE) are nonparametric techniques that are often used in home range analyses and allow researchers studying social networks to generate interaction matrices based on shared space use. We explored the use of KDE analysis and the effects of altering KDE input parameters on social network metrics using data from a natural population of the spatially persistent forked fungus beetle, Bolitotherus cornutus.
Nonequilibrium Green’s function method for a quantum Hall device in a magnetic field

We have developed a practical approach for the inclusion of magnetic fields in the nonequilibrium Green's function method and we have formulated a general scheme for transport calculations in a multiterminal device with magnetic field. Formulas for the self-energy terms in the presence of magnetic fields have been derived and disorder effects in the potential have been introduced through a model accounting for scattering by impurities. To demonstrate the validity of the model, we have applied it to the quantum Hall effect (QHE), for which a wealth of experimental results and information is readily available. Calculations for a simple structure at zero temperature were first carried out to verify the properties of the solutions over a wide range of conditions. The calculated Green's function results provide the carrier density distribution in the structure, and in order to analyze the QHE results, the resistances ${R}_{\mathrm{xx}}$ and ${R}_{\mathrm{xy}}$ are obtained using B\"uttiker's approach. Our results for the integer QHE show a pattern that clearly resembles the edge state picture of transport. To further validate the theoretical model, comparisons have been conducted with experimental results for a realistic quantum Hall device at finite temperature, obtaining good agreement.
Power-aware scheduling for AND/OR graphs in real-time systems

Power aware computing has become popular, recently and many techniques have been proposed to manage processor energy consumption for traditional real-time applications. In this paper, we are concerned mainly with the AND/OR model of real-time applications that have different execution paths consisting of different tasks. The contribution of this paper is twofold. First, we propose a greedy slack stealing algorithm to deal with applications represented by AND/OR graphs and prove its correctness in terms of meeting the timing constraints. Then, using statistical information about the applications, we propose a few variations of speculative scheduling algorithms that intend to save energy by reducing the number of speed changes (and, thus, the overhead) while ensuring that the application meets its timing constraints. Some practical issues are also considered, such as shared memory access contention and idle energy consumption. The performance of the algorithms is analyzed with respect to processor energy savings. The results surprisingly show that the greedy slack stealing scheme is better than some speculative schemes and that the greedy scheme is good enough when a reasonable minimal speed exists in the system or when there are only a few (four to six) voltage/speed levels.