cssi/SciSciGPT-SciSciNet huggingface dataset:
Towards a complexity hierarchy of wait-free concurrent objects

The author studies the time complexity of wait-free implementations of a generalized version of consensus, the set-consensus problem, in synchronous message-passing systems. The time complexity of such characteristic problems as consensus and strong renaming have been studied earlier. These two problems seem to exist at two ends of the spectrum, one taking O(n) time, while the other has an O(logn) time complexity. The class of problems introduced represent varying levels of time complexity ranging from O(1) to O(n) and therefore, bridge this gap. It also gives further evidence to support the existence of a non-trivial complexity hierarchy for wait-free implementations of concurrent objects. Both consensus and strong renaming have been linked to certain concurrent data structures, showing that these data objects are powerful enough to solve these problems. This has facilitated the analysis of wait-free implementations of these data objects by reducing this problem to the easier problem of analyzing these decision problems. >
A Time‐Dependent Risk Assessment for Broken Compact Fluorescent Lamps

Environmental Protection Agency (EPA) ambient air quality guidelines are meant to limit long-term exposures of toxins to safe levels. Unfortunately, there is little guidance for what constitutes a safe level from a one-time (or very infrequent) short exposure(s). In the case of mercury, a review of the derivation of the EPA ambient air quality standard shows that it implicitly assumes a tissue burden model. The time dependence of the tissue burden is commonly described in terms of a half-life, a modeling assumption that presumes that the decline in the tissue burden after a single exposure can be approximately described as an exponential decay. In this article, we use a simple exponential tissue burden model to derive a time-dependent no observable adverse effect level (NOAEL) for mercury concentrations in air. The model predicts that tissue body burden will asymptotically approach the EPA air quality level for long exposure times, and reach workplace standard levels for exposures of a few hours. The model was used along with data on mercury levels from experimental work done by the Maine Department of Environmental Protection to evaluate the risks from a broken compact fluorescent lamp in a residential setting. Mercury levels approached the NOAEL only when the debris was left in an almost sealed room. Normal common-sense cleaning measures: removal of debris to an outside area, and ventilation of the room for several minutes, reduced exposures to less than 1% of the NOAEL.
On the Edit Distance from K2,t-Free Graphs

The edit distance between two graphs on the same vertex set is defined to be the size of the symmetric difference of their edge sets. The edit distance function of a hereditary property, H, is a function of p, and measures, asymptotically, the furthest graph of edge density p from H under this metric. In this article, we address the hereditary property Forb K2,t, the property of having no induced copy of the complete bipartite graph with two vertices in one class and t in the other. Employing an assortment of techniques and colored regularity graph constructions, we are able to determine the edit distance function over the entire domain p∈[0,1] when t=3,4 and extend the interval over which the edit distance function for Forb K2,t is known for all values of t, determining its maximum value for all odd t. We also prove that the function for odd t has a nontrivial interval on which it achieves its maximum. These are the only known principal hereditary properties for which this occurs. In the process of studying this class of functions, we encounter some surprising connections to extremal graph theory problems, such as strongly regular graphs and the problem of Zarankiewicz.
Management of patients with multiple rib fractures

Multiple rib fractures in trauma patients are associated with significant morbidity and mortality. Delayed morbidity for patients with rib fractures is often a result of hypoventilation leading to atelectasis, pneumonia, and respiratory failure. Pain management was first recognized as an important factor in preventing complications in these patients. Later, management of the respiratory system became more widely recognized as a major factor in patients' care. It is now known that patients with multiple rib fractures benefit most from adequate pain control, rapid mobilization, and meticulous respiratory care to prevent complications. A protocol based on a synthesis of the existing literature is developed. Development of such a protocol for decisions about rapid mobilization, respiratory support, and pain management is the first step in testing the hypothesis that these interventions will decrease the length of patients' stay in intensive care units.
Influence of Dopant Concentration on Creep Properties of Nd2O3‐Doped Alumina

The microstructural features and tensile creep behavior of Al 2 O 3 doped with Nd 2 O 3 at levels ranging from 100 to 1000 ppm (Nd:Al atomic ratio) were systematically investigated. Compositional mapping, using both high-resolution scanning transmission electron microscopy and secondary ion mass spectroscopy revealed that, for all of the compositions studied, the Nd 3+ ions were strongly segregated to the Al 2 O 3 grain boundaries. Microstructural observations revealed that the solubility of Nd 2 O 3 was between 100 and 350 ppm. Tensile creep tests were conducted over a range of temperatures (1200°-1350°C) and stresses (20-75 MPa). Both the stress and grain-size exponents were analyzed. In selected experiments, controlled grain-growth anneals were used to enable creep testing of samples of the same average grain size but different neodymium concentrations. Independent of dopant level, the neodymium additions decreased the creep rate by 2-3 orders of magnitude, compared with that of undoped Al 2 O 3 . The value of the apparent creep activation energy increased with increased dopant concentration and then saturated at dopant levels exceeding the solubility limit. Overall, the results of the present study were consistent with a creep-inhibition mechanism whereby oversized segregant ions reduce grain-boundary diffusivity by a site-blocking mechanism.
Bound state vibrational spectrum of the 3 9 atom-surface interaction

The potential V(z) = C9z9 − C3z3 is a reasonable parametrization of the atom-surface interaction. We evaluate the discrete spectrum En of bound states for this potential with arbitrary coefficients C9 and C3. The resulting form in the WKB approximation is En = −D [1 − (n + l2)L]6, where L depends on the mass and D is the well depth. We find that the exact solution of the Schrodinger equation can be written in the same form, with n shifted slightly by an amount δn, which we calculate. The results are applied to the case of He near a NaF surface, in which the calculated eigenvalue spectrum agrees well with experimental values.
Familial neurovisceral lipidosis

Histochemical studies on renal tissue obtained from an infant with familial neurovisceral lipidosis indicate that a mucopolysaccharide rather than a glycolipid is the major storage material contained within the vacuoles of the glomerular epithelium. Electron microscopic studies indicate that the storage vacuoles are probably lysosomes. Because of the clinical similarity to Hurler's syndrome and the storage of a mucopolysaccharide, it is suggested that familial neurovisceral lipidosis may be related to the genetic mucopolysaccharidoses.
Modeling the Effect of Oxygen on Photopolymerization Kinetics

Summary: A comprehensive one-dimensional photopolymerization model was utilized to investigate the effect of oxygen on the free-radical photopolymerization kinetics. The spatial profiling aspect of the model provided insight into the heterogeneity of the cure kinetics due to oxygen inhibition, specifically the variance in the concentration profile of monomer and oxygen. Double bond conversion was negligible for the top ten microns of the film due to continuous oxygen diffusion, and increased with increasing depth. Similarly, the oxygen concentration decreased with increasing depth due to the competition between oxygen diffusion time and the polymerization rate. The effect of initiation rate on the extent of oxygen inhibition was investigated for various oxygen concentrations. As the initiation rate increased, the polymerization rate increased, and eventually approached that of a sample in an inert environment. Similarly, as the oxygen concentration was decreased, the polymerization rate increased. The effect of varying the initiation rate on the cure profile in the oxygen-exposed film was also studied. It was found that the unpolymerized tacky layer decreased from 50 µm to 5 µm with a 3 order of magnitude increase in initiation rate. Using the pseudo steady state approximation, the relationship between polymerization rate and initiation rate was derived for films in an oxygen environment. A direct relationship between the polymerization and initiation rate was found for films in air. The polymerization model supported this derivation and found that as the oxygen concentration was decreased, the dependence on initiation rate, or alpha, decreased, reaching the accepted value of 0.5 for alpha in inert environments. Double bond conversion versus film depth and cure time.
Phosphonate Diester and Phosphonamide Synthesis. Reaction Coordinate Analysis by 31P NMR Spectroscopy: Identification of Pyrophosphonate Anhydrides and Highly Reactive Phosphonylammonium Salts1

A series of phosphonochloridates was prepared from the corresponding phosphonate monoesters, and their reactions with alcohols, amines, and the bisnucleophile 4-aminobutan-1-ol have been investigated using 31P NMR spectroscopy. In the conversion of phosphonate monoesters to phosphonochloridates via the addition of thionyl chloride or oxalyl chloride, pyrophosphonate anhydrides were found to be formed readily as byproducts. The anhydrides reacted readily with alcohols, but more slowly than the corresponding phosphonochloridates, and only sluggishly, if at all, with amines. Therefore, when phosphonamides are prepared, anhydride formation must be suppressed. This is accomplished when the monoester is added to the chloridating agent. Unhindered phosphonochloridates reacted predominantly with the amino function of 4-aminobutan-1-ol to furnish the phosphonamidates, whereas a sterically hindered phosphonochloridate demonstrated a preference for O-coupling. This result indictes that the energy gained during P−O b...
Exactly how are fluid intelligence, working memory, and executive function related? Cognitive neuroscience approaches to investigating the mechanisms of fluid cognition

Blair proposes that fluid intelligence, working memory, and executive function form a unitary construct: fluid cognition. Recently, our group has utilized a combined correlational–experimental cognitive neuroscience approach, which we argue is beneficial for investigating relationships among these individual differences in terms of neural mechanisms underlying them. Our data do not completely support Blair's strong position.
Exercise Graded by Heart Rate in Electrocardiographic Testing for Angina Pectoris

Standardization of an exercise electrocardiographic test for myocardial ischemia is desirable. Standardization of exercise should be based upon a standardized challenge to the coronary circulation, not upon a standardized challenge to the skeletal muscles, for the stresses upon the heart are not identical. With the use of heart rate during exercise as an index of cardiac stress, the levels of exercise prescribed on the basis of age, sex, and weight in standard "two-step" test tables produce widely varying levels of cardiac stress-sometimes too low to induce significant ST-segment depression in patients with angina pectoris and, occasionally, much greater than necessary to produce such diagnostic electrocardiographic changes. The graded exercise test, using 85 per cent of the maximal age-predicted heart rate that may be induced by exercise, produces a closer approximation of a standardized cardiac stress, regardless of age, sex, or body build. Its use with angina pectoris patients and normal subjects resul...
Effects of electrical and mechanical stimulation on two foci of spontaneous activity which develop in primary afferent neurons after peripheral axotomy

In 28 Sprague-Dawley rats, unilateral division of the sciatic nerve at the level of the midfemur was performed. Animals were observed for behavioral changes for 1-21 days, and electrophysiological recordings were made from microfilaments dissected from the ipsilateral L5 dorsal rootlets and sciatic nerve from 1 to 14 days postoperatively. Spontaneous discharges of two types were recorded: (1) variable frequency (0-100 Hz) discharges which typically occurred in rhythmic bursts and could be driven by mechanical stimulation of the neuroma; and (2) lower frequency (0.25-14 Hz) irregular activity which persisted after either excision or local anesthesia of the neuroma. The latter activity could also be recorded from the proximal cut end of the sciatic nerve following removal of the neuroma. The first type of activity was felt to be produced from the neuroma while the second originated in the region of the dorsal root ganglion (DRG). Analysis of the conduction velocities of fibers involved in each type of discharge indicated that both involved smaller myelinated filaments. However, the DRG activity involved significantly smaller fibers with conduction velocities in the A delta range. Spontaneous activity was recorded at 3 and 4 days for the neuroma and DRG activity, respectively. Ongoing discharges maximized at 7-10 days and were rare by 14 days. Autotomy of the ipsilateral foot was found to occur over a similar time course. Tetanic electrical stimulation (100 Hz) produced either little change in the baseline firing rate or prolonged afterdischarges in fibers manifesting neuroma activity. In fibers with ongoing activity of DRG origin, stimulation produced a stereotyped, brief low-frequency afterburst and then prolonged inhibition of firing. Mechanical stimulation of the neuroma produced both brief increases in spontaneous discharges and prolonged afterdischarges. In fibers with spontaneous DRG activity, minimal mechanical stimulation of their ganglion of origin produced high-frequency firing. This study demonstrates that peripheral axotomy of DRG neurons produces spontaneous activity distinct from ongoing neuroma activity in a proportion of fibers which are potentially nociceptive (A delta) as well as abnormal mechanosensitivity of the DRG. Furthermore, electrical stimulation of these fibers produces prolonged inhibition of the discharge. This finding may partially explain the prolonged relief of symptoms patients with chronic pain of peripheral origin may experience following peripheral tetanic electrical stimulation.
BH4 therapy impacts the nutrition status and intake in children with phenylketonuria: 2-year follow-up

The impact of tetrahydrobiopterin (BH4) treatment on phenylalanine tolerance, medical-food consumption, and nutrition status in patients with phenylketonuria (PKU) was investigated. Six children (5–12 years) with well-controlled PKU, responding to a BH4 dose of 20 mg/kg per day, were assessed for 24 months. Mean dietary phenylalanine tolerance increased from 421 ± 128 to 1470 ± 455 mg/day. Height Z scores significantly improved from 0.25 ± 0.99 at baseline to 0.53 ± 1.16 at 24 months (p for trend < 0.001). Patients tolerated more phenylalanine and more intact protein and required less medical food (protein supplement). Improved linear growth and nutrition status was seen over the course of the 24-month follow-up. Due to the variation in phenylalanine tolerance, dietary recommendations should be tailored to the patient’s individual requirements.
Effects of short- and long-term fasting on plasma and stomach ghrelin, and the growth hormone/insulin-like growth factor I axis in the tilapia, Oreochromis mossambicus.

Ghrelin is a highly conserved peptide hormone secreted by the stomach, which is involved in the regulation of food intake and energy expenditure. Ghrelin stimulates growth hormone (GH) release, and increases appetite in a variety of mammalian and non-mammalian vertebrates, including several fish species. Studies were conducted to investigate the effect of feeding and fasting on plasma and stomach ghrelin, and the growth hormone/insulin-like growth factor I (IGF-I) axis in the Mozambique tilapia, a euryhaline teleost. No postprandial changes in plasma and stomach ghrelin levels or stomach ghrelin mRNA levels were observed. Plasma levels of GH, IGF-I and glucose all increased postprandially which agrees with the anabolic roles of these factors. Fasting for 4 and 8 d did not affect ghrelin levels in plasma or stomach. Plasma GH was elevated significantly after 4 and 8 d of fasting, while plasma IGF-I levels were reduced. Plasma ghrelin levels were elevated significantly after 2 and 4 wk of fasting, but no change was detected in stomach ghrelin mRNA levels. Four weeks of fasting did not affect plasma GH levels, although plasma IGF-I and glucose were reduced significantly, indicating that GH resistance exists during a prolonged nutrient deficit (catabolic state). These results indicate that ghrelin may not be acting as a meal-initiated signal in tilapia, although it may be acting as a long-term indicator of negative energy balance.
Economics of offshore outsourcing: anything new under the sun?

Based on International Economics, this paper provides a theoretical perspective of the economic rationale behind the current phenomenon of offshore outsourcing of IT related activities.
CK2α is essential for embryonic morphogenesis

CK2 is a highly conserved serine–threonine kinase involved in biological processes such as embryonic development, circadian rhythms, inflammation, and cancer. Biochemical experiments have implicated CK2 in the control of several cellular processes and in the regulation of signal transduction pathways. Our laboratory is interested in characterizing the cellular, signaling, and molecular mechanisms regulated by CK2 during early embryonic development. For this purpose, animal models, including mice deficient in CK2 genes, are indispensable tools. Using CK2α gene-deficient mice, we have recently shown that CK2α is a critical regulator of mid-gestational morphogenetic processes, as CK2α deficiency results in defects in heart, brain, pharyngeal arch, tail bud, limb bud, and somite formation. Morphogenetic processes depend upon the precise coordination of essential cellular processes in which CK2 has been implicated, such as proliferation and survival. Here, we summarize the overall phenotype found in CK2α −/− mice and describe our initial analysis aimed to identify the cellular processes affected in CK2α mutants.
Interleukin-2 induces N-glycosylation in T-cells: characterization of human lymphocyte oligosaccharyltransferase.

We have investigated the enzyme mediating N-glycosylation in "resting" and activated lymphocytes. Normal peripheral blood lymphocytes (PBLs) were found to have low activity for glycosylation of a synthetic glycan acceptor peptide. N-glycosylation activity increased 10-fold after mitogen activation of PBLs. N-glycosylation activity remained elevated during long-term culture and expansion of human lymphocytes when growth was supported by interleukin-2. To our knowledge, this is the first biochemical evidence for induction of endoplasmic reticulum functions during T-cell activation. The enzyme mediating N-glycosylation in lymphocytes was localized predominantly but not entirely to a microsomal organelle by subcellular fractionation. After solubilization and 85-fold purification from salt-washed microsomes, the enzyme preparation contained four predominant proteins. N-terminal sequence analysis identified the proteins as ribophorin I, ribophorin II (doublet), and a 50-kDa homologue of Wbp1, a yeast protein essential for N-glycosylation.
Outlook: The subprime lending crisis: Focus on the problem: Subprime borrowers in trouble

Abstract Public policy should be directed at serving the large number of borrowers who have recently taken out subprime loans and who are at serious risk of losing their homes when their mortgages reset. Practicing forbearance and providing counseling for defaulting homeowners, as well as allowing them to refinance into a Federal Housing Administration loan, can be particularly helpful. Broad changes in housing programs and in the structure of the mortgage market should be considered on their merits as good or bad public policy for the long term, not simply as solutions to the subprime problem.
Sturge-Weber syndrome: a study of cerebral glucose utilization with positron emission tomography.

We measured local cerebral metabolic rate for glucose (ICMRGIc) using positron emission tomography (PET) in six children with Sturge-Weber syndrome (SWS) and in six neurologically asymptomatic children with facial capillary hemangloma suggestive of SWS. Children with advanced SWS showed markedly depressed ICMRGIc in the anatomically affected cerebral hemisphere in a distribution that extended beyond the abnormalities depicted on computed tomography scan. In two infants with SWS and recent seizure onset, interictal PET revealed a paradoxical pattern of increased ICMRGIc in the cerebral cortex of the anatomically affected hemisphere. In one of these infants, ICMRGIc was also increased in the contralateral cerebellum, suggesting activation of the cortico-ponto-cerebellar circuitry. Subsequent PET (28 months later) in this child revealed the typical ICMRGIc pattern seen in advanced SWS. Further study of this transient ICMRGIc increase may be important in disclosing the pathogenesis of unilateral cerebral degeneration in SWS. In neurologically asymptomatic children with the facial stigmata of SWS and in children with early SWS, PET provides a sensitive measure of the extent and degree of cerebral metabolic impairment. Serial PET studies in children with SWS can be used to assess disease progression and, together with computed tomography or magnetic resonance imaging, may be useful in the selection of suitable candidates for cerebral hemispherectomy or focal cortical resection.
Looping mechanics of rods and DNA with non-homogeneous and discontinuous stiffness

Abstract DNA molecules may form loops in response to binding with regulatory proteins that control the expression of genes. While DNA looping is a widely accepted gene regulatory mechanism, basic questions regarding the mechanics of the looping process remain open. The present paper contributes a computational rod model that accounts for non-homogeneous and discontinuous changes in stiffness to support the analysis of DNA looping. We pursue this objective in two steps. First, we illustrate the effects of non-homogeneous stiffness on the looping of generic rods under pure torsion. Results computed for this idealized case support our intuition that elastic deformation and strain energy localize in ‘soft’ regions and that equilibrium bifurcations are sensitive to non-homogenous stiffness. Next, we extend the formulation to describe the combined bending, torsion and compression induced on DNA by the LacR protein. We demonstrate that while moderate stiffness variations have only modest influence on LacR-mediated DNA looping, highly localized softening (e.g., ‘kinkable’ or ‘melted’ subdomains) may substantially reduce the energetic cost of looping and profoundly affect loop geometry.
NCHRP Report 350 Crash Test Results for Connecticut Truck-Mounted Attenuator

The results of four full-scale crash tests performed on the Connecticut Truck Mounted Attenuator (CTMA) are summarized. The tests were conducted in accordance with the guidelines of NCHRP Report 350 for Test Level 2 devices. NCHRP Report 350 specifies two required and two optional tests. The four crash tests passed all requirements of NCHRP Report 350. No repeat tests were required, and the results were uniformly excellent. The successful CTMA test series is the first of several NCHRP Report 350 test programs that are anticipated to gain compliance for various impact attenuation systems designed and developed in Connecticut.
Cerium(III) as a Stabilizer of Perfluorinated Membranes Used in Fuel Cells: In Situ Detection of Early Events in the ESR Resonator

We present experiments in an in situ fuel cell (FC) inserted in the resonator of the ESR spectrometer that allowed separate monitoring of radical formation at anode and cathode sides. The in situ FC was operated at 300 K under closed and open circuit voltage conditions, CCV and OCV, respectively, with a membrane-electrode assembly (MEA) based on Nafion 117 10% neutralized by Ce(III) and Pt as catalyst, notation MEA/Ce. The presence of the unstable intermediates was determined by addition of 5,5-dimethylpyrroline-N-oxide (DMPO) as a spin trap, simulation of the spectra from the DMPO adducts, and analysis of the corresponding magnetic parameters and relative intensities. The main objective of these experiments was to identify early events in the mitigation mechanism of Ce(III) on Nafion degradation. The present results were therefore compared to an in situ FC based on Nafion 117 in the acid form, notation MEA/H (Danilczuk et al. J. Phys. Chem. B 2009, 113, 8031−8042) that served as baseline. The differences...
Glutathione synthesis and its role in redox signaling

Glutathione (GSH) is the most abundant antioxidant and a major detoxification agent in cells. It is synthesized through two-enzyme reaction catalyzed by glutamate cysteine ligase and glutathione synthetase, and its level is well regulated in response to redox change. Accumulating evidence suggests that GSH may play important roles in cell signaling. This review will focus on the biosynthesis of GSH, the reaction of S-glutathionylation (the conjugation of GSH with thiol residue on proteins), GSNO, and their roles in redox signaling.
THE B ISOTOPIC COMPOSITION OF ARC LAVAS FROM MARTINIQUE, LESSER ANTILLES

Island-arc samples from Martinique, Lesser Antilles, are enriched in B relative to oceanic crust or the mantle, with B contents varying between 5 and 54 ppm, and have δ11B falling in a range between 1.8‰ and −5.3‰, less than the δ11B of altered oceanic crust. The combination of these results indicates that both sediments and altered oceanic crust must have been involved in the generation of those magmas, since the abundance of B in the mantle is too low to produce such low δ11B values with such high B concentrations. B content and δ11B are not correlated, showing that the amount of B added to the arc magma was decoupled from its isotopic composition by the mixing of at least three distinct components. Boron concentrations, considered in conjunction with 87Sr/86Sr, 143Nd/144Nd, δ18O and δ11B data, show that variable amounts of B were added by a B-enriched fluid to different batches of mantle-derived magma. The B, Sr and Nd isotopic compositions of these samples are consistent with a two-stage process in which enriched magma is produced in the mantle wedge by the addition of an aqueous fluid derived from dehydrating, subducting lithosphere and then modified during ascent by assimilation of variable amounts of sediment and altered oceanic crust. Most of the B contained in the fluid was probably derived from altered oceanic crust plus as little as 3% sediment, while the material involved in assimilation was apparently largely continentally derived sediment. A two-stage process like this also explains the distribution of δ18O, within the context of the B, Sr and Nd isotopic compositions of Martinique arc lavas.
Generation of all permutation and combination of Matchings in a Bipartite graph and its applications

This paper discusses an approach to generate all permutations and combinations of valid matching edges, valid pass-through edges and un-matched edges of a Bipartite graph (B-graph). Matchings would range from no-match to perfect-match. B-graph is represented as matrix where rows and columns represent two disjoint sets of vertex and its values represent the edges. It involves 3 stages of operation to get all sets of valid matched edges, pass-through edges and unmatched edges of a B-graph. In first stage, the rows and columns of a perfect-match B-graph matrix are swapped to get all permutations. In second stage, each of those B-graph matrix are superimposed over set of binary-matrix (generated by incrementing integers) and AND logical operation is performed on the matrix values to create all combinations of the B-graph. In third stage, the invalid B-graphs are eliminated by checking for invalid-pass-through edges. If pass-through edges are not required, then third stage can be eliminated. Generating all permutations and combinations of B-graphs aids as an input to validate various Matching algorithms and also to represent Redundancy models of High Availability platforms.
Breast cancer in African Americans: from patient to survivor.

Purpose: The purpose of this synthesis is to explore the experience of the transition from cancer patient to survivor in African Americans with breast cancer, addressing the risk/ protective factors that have an influence on successful transition using the social ecological model. Methods: The investigator searched CINAHL, PubMed, and PsycInfo databases. Articles were assessed for content addressing risk and protective factors of transition in African American breast cancer survivorship. Eleven research articles were obtained and synthesized. Results: Risk and protective factors exist at all levels of the social ecological model. Emotional issues are prevalent after the cessation of cancer treatment, enhanced by the lack of social support in this population. Spirituality was shown to be present in many levels as a protective factor during this period. Conclusions and Implications for Practice: The entrance to survivorship represents a time of increased stressors and subsequent coping. Through careful iden...
Velocity Dispersion and the Redshift-Space Power Spectrum

A large (N ~ 17 × 106) high-resolution N-body simulation of a standard cold dark matter (CDM) universe is used to investigate the effects of peculiar velocities on the power spectrum of galaxies in redshift space. The unprecedented dynamical range of the simulation code allows galaxy halos to be resolved in the numerical data while maintaining good statistical sampling on large scales. We present evidence that the redshift-space power spectrum Ps(k) can be related to its real-space counterpart by means of a simple filter function which reflects both small-scale velocity dispersion and large-scale linear flows. After transformation to redshift space, we find that the power spectrum is insensitive to the normalization of the CDM model at scales below 20 h-1 Mpc. Hence Ps(k) does not provide an unambiguous cosmological constraint at small scales. Nonetheless, it is significant that the redshift-space power spectra from CDM models with two different normalizations both compare remarkably well with results from the galaxies in the IRAS 1.2 Jy survey (Fisher et al.) on scales between 1 and 50 h-1 Mpc. By excluding a fraction of the most tightly bound halos, we create a galaxy catalog with 80% of the original objects in the lower normalization model that matches both the IRAS power spectrum and the inferred pairwise velocity dispersion on megaparsec scales. Thus, in contrast to previous reports, we find that the CDM scenario does not produce excess power at small scales.
Does the combination of solid and liquid swallows improve esophageal manometry in patients with dysphagia

Does the combination of solid and liquid swallows improve esophageal manometry in patients with dysphagia
Stress relaxation at wave fronts in one-dimensional media described by non-linear viscoelastic models

Abstract Constitutive equations are presented for non-linear viscoelastic materials under variable stress loading nd are interpreted in terms of non-linear viscoelastic models. Analytical solutions are obtained for stress, velocity and strain at the wave front in an impulsively loaded semi-infinite rod of material described by these non-linear constitutive equations within the assumptions of small deformation theory.
Nonlinear analysis of reinforced concrete structures

Abstract For the prediction of yield and failure of concrete under combined stress, a generalization of the Mohr-Coulomb behavior is made in terms of the principal stress invariants. The generalized yield and failure criteria are developed to account for the two major sources of nonlinearity: the progressive cracking of concrete in tension, and the nonlinear response of concrete under multiaxial compression. Using these criteria, incremental stress-strain relationships are established in suitable form for the nonlinear finite element analysis. For the analysis of reinforced concrete members by finite elements, a method is introduced by which the effect of reinforcement is directly included. With this approach, the stress-strain laws for the constituent materials of reinforced concrete are uncoupled permitting efficient and convenient implementation of a finite element program. The applicability of the method is shown on sample reinforced concrete analysis problems.
Influence of decaying sweet potato crop residues on nutrient uptake of sweet potato plants

Sweet potato cultivar ‘Centennial’ (Ipomoea batatas (L.) Lam.) indicator plants were grown in either coarse silica sand or silt loam soil amended with either dried peatmoss, cowpea (Vigna unguiculata (L.) Walp.) shoots, sweet potato vines or sweet potato roots at a rate of 1.67% (w/w). The effects of these plant residues on nutrient concentration and uptake of sweet potato shoots were compared with a non-amended control. Whole shoots were analyzed for P, K, Ca, Mg, S, Na, Fe, Zn, Mn, B, Al and Cu. Shoot dry weights were less for plants grown in either sweet potato vine or root residue, regardless of growing media, suggesting that sweet potato residues have an allelopathic effect. Indicator plants grown in sweet potato crop residues had lower concentrations of Ca, Mg and S. Tissue analysis data expressed as plant content suggested reduced uptake of P, K, Ca, Mg, S, Zn, B and Cu. Significant correlations between plant growth and Ca, Mg and S concentrations in shoots were found. Although growth inhibition could not be associated conclusively with reduced uptake of a particular nutrient, the altered uptake of these three nutrients might affect plant growth in soils which contain decaying sweet potato crop residues.
Cyclic nucleotide metabolism in electroplax of Electrophorus electricus.

— In order to describe the regulation of cyclic nucleotide metabolism in a cholinergic tissue, the properties of cyclic nucleotide phosphodiesterase were determined in electroplax of Electrophorus electricus and compared to those of mammalian brain. Electroplax phosphodiesterase was Mg2+ -dependent. localized in the soluble fraction and displayed normal linear Lineweaver-Burk kinetics (Km: cyclic AMP. 1.4 μm; cyclic GMP, 0.54 μm). No low affinity (i.e. high Km) activity was detected. These results were correlated with comparatively low tissue levels of cyclic AMP (67 pmol/g) and cyclic GMP (3.2 pmol/g). Attempts were made to detect calcium-dependent phosphodiesterase because of the presence of large amounts of the calcium-dependent regulator protein (CDR) in electroplax, as this protein has been shown to activate brain phosphodiesterase. Assay with EGTA under a variety of conditions revealed that no calcium-dependent activity could be detected. Preparation of CDR-deficient phosphodiesterase also failed to produce calcium-dependent activity. Assay of phosphodiesterase in other cholinergic tissues revealed calcium-dependent activity in Electrophorus muscle and rat diaphragm but not in Torpedo electroplax. The results suggest that calcium-dependent activity is not a significant portion of phosphodiesterase in electroplax and indicate alternate roles for CDR in electric tissue.
N-terminal deletions of the øX174 external scaffolding protein affect the timing and fidelity of assembly

Abstract The first α-helices of Microviridae external scaffolding proteins function as coat protein substrate specificity domains. Mutations in this helix can lengthen the lag phase before progeny production. 5′ deletion genes, encoding N-terminal deletion proteins, were constructed on plasmids and in the oX174 genome. Proteins lacking the first seven amino acids were able to rescue a nullD mutant when expressed from a plasmid. However, the lag phase before progeny production was lengthened. The oX174 mutant with the corresponding genomic gene grew very poorly. The molecular basis of the defective phenotype was complex. External scaffolding protein levels were reduced compared to wild-type and most of the viral coat protein in mutant infected cells appears to be siphoned off the assembly pathway. Second-site suppressors of the growth defects were isolated and appear to act via two different mechanisms. One class of suppressors most likely acts by altering mutant external scaffolding protein expression while the second class of suppressors appears to act on the level of protein–protein interactions.
Does bilingualism twist your tongue

The current study investigated whether bilingualism affects the processing of sub-lexical representations specifying the sound structure of words. Spanish-English bilinguals, Mandarin-English bilinguals, and English-only monolinguals repeated English tongue twisters. Twister materials had word or nonword targets (thus varying in whether lexical information did or did not support sound processing), and similar or dissimilar sounds (thus varying in difficulty with respect to competition at a sub-lexical level). Even though bilinguals had learned English at an early age, and spoke English without an accent, Spanish-English bilinguals produced significantly more twister errors than monolinguals, particularly in the absence of lexical support. Mandarin-English bilinguals were also disadvantaged, but more consistently across all twister types. These results reveal that bilingual disadvantages extend beyond the lexical level to affect the processing of sub-lexical representations. More generally, these findings suggest that experience with sound structures (and not simply their intrinsic complexity) shapes sub-lexical processing for all speakers.
Segregated school effects on first grade reading gains: Using propensity score matching to disentangle effects for African-American, Latino, and European-American students

Abstract Increasing evidence from observational studies indicates that students attending minority segregated schools are at risk for constrained performance in reading. However, analyses of data gathered under observational conditions may yield biased results. Using data from the Early Childhood Longitudinal Study, 1998–1999 Kindergarten Cohort, this study used propensity score matching to address selection bias due to students’ observed socio-economic, literacy, and social-emotional background characteristics, allowing for a less biased estimate of minority segregated schooling on African-American, Latino, and European-American students’ reading gains in first grade. We found that African-American students attending segregated schools made less gain in reading across the first grade year than African-American students in non-segregated schools. There was no evidence for significant negative effects of segregation on reading gains for Latino and European-American students.
A genetic algorithm for intelligent imaging from quantum-limited data

Abstract A parallel genetic algorithm is presented for 2-D object recognition and simulataneous estimation of object position, magnification and orientation from quantum-limited sensor data. Traditional approaches to this problem are based on matching a concise set of features (boundaries, corners, moments, etc.) from the sensor data to a corresponding set of model features. These approaches break down at low SNR due to a deluge of artifacts among the data features, and inconsistencies arising from the lack of optimal interaction between high-level and low-level vision processes. As a first step towards overcoming the above hurdles, this paper presents a drastic departure from conventional vision-based approaches that (i) avoids the computation of features from noisy data, and (ii) uses a synergistic interaction of high-level and low-level vision processes to avoid inconsistencies. The combined vision problem is posed as a large-scale global optimization over a single objective function that directly involves the sensor data, the noise model and object templates. The optimization is accomplished using a genetic algorithm that runs on a parallel computer with 40 Transputers. Experimental results are presented which demonstrate robust operation and high accuracy with quantum-limited (5–10 events/pixel) data.
Ion conduction and selectivity in acid-sensing ion channel 1.

The ability of acid-sensing ion channels (ASICs) to discriminate among cations was assessed based on changes in conductance and reversal potential with ion substitution. Human ASIC1a was expressed in Xenopus laevis oocytes, and acid-induced currents were measured using two-electrode voltage clamp. Replacement of extracellular Na+ with Li+, K+, Rb+, or Cs+ altered inward conductance and shifted the reversal potentials consistent with a selectivity sequence of Li ∼ Na > K > Rb > Cs. Permeability decreased more rapidly than conductance as a function of atomic size, with PK/PNa = 0.1 and GK/GNa = 0.7 and PRb/PNa = 0.03 and GRb/GNa = 0.3. Stimulation of Cl− currents when Na+ was replaced with Ca2+, Sr2+, or Ba2+ indicated a finite permeability to divalent cations. Inward conductance increased with extracellular Na+ in a hyperbolic manner, consistent with an apparent affinity (Km) for Na+ conduction of 25 mM. Nitrogen-containing cations, including NH4+, NH3OH+, and guanidinium, were also permeant. In addition to passing through the channels, guanidinium blocked Na+ currents, implying competition for a site within the pore. The role of negative charges in an external vestibule of the pore was evaluated using the point mutation D434N. The mutant channel had a decreased single-channel conductance, measured in excised outside-out patches, and a macroscopic slope conductance that increased with hyperpolarization. It had a weakened interaction with Na+ (Km = 72 mM) and a selectivity that was shifted toward larger atomic sizes. We conclude that the selectivity of ASIC1 is based at least in part on interactions with binding sites both within and internal to the outer vestibule.
Arsenic Bioaccumulation in Freshwater Fishes

ABSTRACT The arsenic ambient water quality criterion (AWQC) for protection of human health via ingestion of aquatic organisms is currently 0.14 μ g/L. This AWQC is derived using a bioconcentration factor (BCF) of 44, which is a consumption-weighted average based on two data points for oysters and fish that was proposed by the U.S. Environmental Protection Agency in 1980 for broad application to freshwater and marine environments. This BCF is based on the assumption that bioaccumulation is a simple linear function of the exposure concentration. In the nearly quarter of a century since this BCF was promulgated, there have been additions to the arsenic bioaccumulation database and a broader scientific understanding of bioaccumulation mechanisms and how they can be applied to estimating tissue concentrations in aquatic organisms. From this database, we identified 12 studies of arsenic bioaccumulation in freshwater fishes in order to explore differences in laboratory-generated BCFs and field-generated bioaccum...
Assessing the potential of hybrid hpc systems for scientific applications: a case study

We have conducted a detailed study to understand the po-tential of hybrid CPU/FPGA High-Performance Computers for improving the performance of data-intensive, scientific applications. In particular, we have focused on an application in proteomics (Polygraph), which is representative of many types of computational analysis applications in the lifesciences: it focuses on extracting useful information from a large body of experimentally collected data (identifying ob-served peptide spectra collected from a mass spectrometer against a well-known protein database). Our preliminary analysis of Polygraph found that morethan half (51%) of the computation time was spent in three routines. We have implemented an FPGA version of themost computationally-intensive routine (20% of the time)on a Cray XD-1 system, and measured the overall speed up achieved in comparison to an optimized software version ofthe routine running on the Cray XD-1's native Opteron processors. We have achieved computational speedups of up to9.16. When we include data movement costs, the overall speedup is reduced to 1.78. We discuss the design and implementation strategies thatled to these results, as well as advantages and limitations we found on the Cray XD-1 platform. We also addressthe advantages and limitations of current development environments, as well as discuss relevant issues we found in our experience as hybrid CPU/FPGA programming model "users".
Morning sickness: impact on offspring salt preference

These studies examined the relationship between salt preference of adult offspring and their mothers' symptoms of morning sickness during pregnancy. College students who could provide information about their mothers' symptoms of morning sickness completed a survey about their dietary salt intake (study 1; n = 169) or rated and consumed ten snack foods (study 2; n = 66). In study 1 a salt-use score was calculated based on responses to the Salt Intake Questionnaire; offspring of women with moderate or severe vomiting reported a significantly higher level of salt use (p < 0.01) than those whose mothers report little or no symptoms. In study 2 saltiness and pleasantness ratings of high-salt foods, intake of those foods and total sodium intake were the focus of analysis. Offspring of women reporting moderate or severe vomiting showed a significantly greater preference for the snack food subjects rated as saltiest than those whose mothers reported no or mild vomiting. They also ate more of that food and consumed more total sodium during the test session. Effects were stronger in Caucasian than Asian subjects. These studies suggest that moderate to severe vomiting during pregnancy can be associated with significantly higher salt intake in offspring. Thus, a gestational event may be an important determinant of salt intake and preference in adulthood.
A Proposed Category for the Diagnostic and Statistical Manual of Mental Disorders (DSM): Pervasive Labeling Disorder

The purpose of this essay is to propose a new diagnostic category for inclusion in the American Psychiatric Association’s Diagnostic and Statistical Manual ofMental Disorders, better known as the DSM. As noted in a recent edition (American Psychiatric Association, 1987), the DSM should be viewed as “only one still frame in the ongoing process of attempting to better understand mental disorders.” The category proposed here represents a significant contribution to the composition of the next still frame by focusing on one of the most ubiquitous, yet least recognized, of all mental disorders.
Experimental Stability Studies of the Herringbone-Grooved Gas-Lubricated Journal Bearing

Herringbone grooved gas lubricated journal bearing stability, testing effects of geometries and clearances on onset speed for half frequency whirl