cssi/SciSciGPT-SciSciNet huggingface dataset:
Histogenesis and cell lineage analysis of medulloblastomas

Although the histopathology, ultrastructural features, and cellular immunoreactivity for neuron-specific enolase and synaptophysin suggest that medulloblastomas are neuronal in character, the histogenesis of these tumors has not been firmly established due to conflicting observations surrounding the expression of intermediate filament proteins. In the present study the question of cell lineage in medulloblastomas was re-explored by examining tumors for the presence of neurofilament protein using a highly sensitive assay which employs a cocktail of monoclonal antibodies, as well as A2B5 antigen, and glial fibrillary acidic protein. With this assay, 12 of 14 tumors tested (86%) expressed high levels of both neurofilament protein and A2B5 antigen, whereas glial fibrillary acidic protein was either absent or expressed in very low percentages of the cells. The distributions of neurofilament and A2B5 antigens closely paralleled one another. These observations suggest that medulloblastomas have a common histogenesis from A2B5+ progenitor cells, and consistently manifest a trend toward neuronal rather than glial differentiation.
Sintering kinetics of supported metals: new perspectives from a unifying GPLE treatment

Abstract Studies of sintering kinetics of conventional supported metal catalysts are reviewed. Available kinetic data for sintering have been reanalyzed using the new General Power Law Expression (GPLE), which provides the capability of treating these data in a consistent, unifying fashion such that quantitative comparisons regarding effects of reaction conditions and catalyst properties are possible for the first time. It is shown that all available dispersion-versus-time data can be fitted to either first or second order GPL kinetics. From the analysis of these data new conclusions arise regarding the effects of atmosphere, time, temperature, support, promoters, and metal on the thermal stability of supported metals.
A sensitive dichromate dosimeter for the dose range, 0.2–3 kGy

Abstract The response of aqueous dichromate dosimeters can be enhanced by adding small controlled amounts of organic reducing agents, however, such additives cause instabilities before and after irradiation. A choice is made of combinations of potassium dichromate, silver dichromate, perchloric acid, with the organic agent, acetic acid, to enhance appreciably the radiation chemical yield, G(-Cr 2 O 7 ) -2 and still have sufficient stability for practical use in dosimetry in the food irradiation range. The reduction yield is thereby increased from the reported value for the classic K-Ag dichromate dosimeter (G ≅ 0.04 μmol J -1 ) to G ≅ 0.17 μmol J -1 . This enhancement allows the dosimeter to be used with good precision down to the upper part of the dose range of the Fricke dosimeter (≈ 200 Gy) up to the lower part of the dose range of the conventional K-Ag dichromate dosimeter (≈ 3000 Gy). Because of instability of the solutions containing acetic acid, however, there is the limitation that spectrophotometry should not be made until at least three hours after irradiation.
Drinking water contribution to aggregate perchlorate intake of reproductive-age women in the United States estimated by dietary intake simulation and analysis of urinary excretion data.

Estimates of perchlorate intake by the US population can be derived from either urinary excretion data or through simulation of dietary intake. Estimates from surveys of urinary excretion (NHANES) are subject to substantial uncertainty owing to the small numbers of subjects for which data are currently available. In addition, current excretion estimates are derived from “spot” urine samples and include a component of short-term (intra-day) variability that may give biased estimates of the variability in average daily intakes. Previous dietary estimates have generally not included any contribution from drinking water, owing to a lack of data related to perchlorate concentrations in water supplies. In this paper, we derive simulation (Monte Carlo) estimates of dietary perchlorate intake distributions for reproductive-age women, which include explicit contributions from drinking water, and compare them to estimates based on urinary excretion. Perchlorate concentrations in water were estimated based on measurements from the US Environmental Protection Agency's UCMR1 database, and from other regional studies of perchlorate contamination. We find that including the drinking water contributions in the dietary simulations yields increases in the population's geometric mean perchlorate intake of 3–8 percent, with a conservative maximum of about 24 percent, compared to intakes estimated based on food intake alone. The intake distributions estimated from dietary and water consumption were found to be very similar to estimates based on creatinine-adjusted perchlorate excretion data from the NHANES, except for having lower population variability. When the dietary simulation data were adjusted to include a contribution from short-term variability similar to that in the “spot” urine samples, the variability in the NHANES and diet-derived estimates were found to be very similar. Our analyses indicate that a reasonable upper-bound estimate for the 95th percentile perchlorate intake among women of reproductive age in the US is on the order of 1.5 × 10−4 mg/kg/day.
Delta-configurations: Flare activity and magnetic-field structure

Complex sunspots in four active regions of April and May 1980, all exhibiting regions of magnetic classification delta, were studied using data from the NASA Marshall Space Flight Center vector magnetograph. The vector magnetic field structure in the vicinity of each delta was determined, and the location of the deltas in each active region was correlated with the locations and types of flare activity for the regions. Two types of delta-configuration were found to exist, active and inactive, as defined by the relationships between magnetic field structure and activity. The active delta exhibited high flare activity, strong horizontal gradients of the longitudinal (line-of-sight) magnetic field component, a strong transverse (perpendicular to line-of-sight) component, and a highly non-potential orientation of the photospheric magnetic field, all indications of a highly sheared magnetic field. The inactive delta, on the other hand, exhibited little or no flare production, weaker horizontal gradients of the longitudinal component, weaker transverse components, and a nearly potential, non-sheared orientation of the magnetic field. We conclude that the presence of such sheared fields is the primary signature by which the active delta may be distinguished, and that it is this shear which produces the flare activity of the active delta.
Sedimentation Rates in a Coastal Marsh Determined from Historical Records

Historical records indicate that Flax Pond, a smallSpartina alterniflora marsh located on the north shore of Long Island, New York, was opened to marine waters in 1803. This opening is recorded in the sediments by a sharp transition from sedge (brackish or fresh water) peat toSpartina (salt marsh) peat. This dated horizon was used to calculate an average net rate of vertical accretion of 2.5 mm/yr and a maximum net rate of 4.7 mm/yr. These estimates may serve to predict the rate at whichSpartina marshes are able to recover from physical disturbance. *** DIRECT SUPPORT *** A00BY066 00002
Performance search engine driven by prior knowledge of optimization

For scientific array-based programs, optimization for a particular target platform is a hard problem. There are many optimization techniques such as (semantics-preserving) source code transformations, compiler directives, environment variables, and compiler flags that influence performance. Moreover, the performance impact of (combinations of) these factors is unpredictable. This pa- per focuses on providing a platform for automatically searching through search space consisting of such optimization techniques. We provide (i) a search-space description language, which enables the user to describe optimization options to be used; (ii) search engine that enables testing the performance impact of optimization options by executing optimized programs and checking their results; and (iii) an interface for implementing various search algorithms. We evaluate our platform by using two simple search algorithms - a random search and a casetree search that heuristically learns from the already examined parts of the search space. We show that such algorithms are easily implementable in our plat- form, and we empirically find that the framework can be used to find useful optimized algorithms.
Remediation of chronic attention deficits in traumatic brain-injured patients

The present study evaluated an A-B-A single case design attention-remediation program for traumatically brain-injured survivors with chronic attention deficits. Four adult male TBI survivors participated in an intensive, hierarchically ordered, attention-remediation program based on Posner's four-component model of attention. No clinically significant improvement was obtained on the attentional measures, neuropsychological variables, psychological characteristics, activities of daily living, or subjective ratings of changes in attentional abilities. The efficacy of this attention-remediation program for TBI survivors is examined in light of other outcome studies.
A Study of Catalyst Support Systems for Fume-Abatement of Hydrocarbon Solvents

In a stainless steel pilot plant system, operating with combined thermal incineration and catalytic oxidation, studies have been made of the influence of catalyst-support geometry on abatement efficiency. Catalyst supports tested were ceramic spherical pellets, metal foils, and ceramic honeycomb structures, all with precious metal catalyst. Data obtained cover a range of space velocities from 30,000 to 175,000 scf/hr— cu ft bed and a range of catalytic reactor temperatures from 150 to 450°C. Results show that optimum fume-abatement performance is obtained by combining incineration and catalytic oxidation and that catalyst support geometry has a significant effect on performance.
Blood loss severity prediction using game theoretic based feature selection

Detection of hypovolemia in the early stages of hemorrhage is an important but unsolved problem in medicine. Many preventable deaths amongst critically injured patients happen due to delayed treatment of uncontrolled hemorrhage. Using a database of physiological signals collected during simulated hemorrhage on human subjects, our research applies a variety of signal processing techniques to extract a multi- tude of features that enable the prediction of the severity of hemorrhage. In this study, a novel feature selection method based on coalition game theory has been proposed which helps identify the most valuable features and thereby reduce the size of the feature space. This reduction in feature space not only improves the efficiency, but also improves the prediction accuracy and reliability of the developed model. This feature selection algorithm is independent of the underlying classifi- cation method and can be combined with any classification method based on the employed data. The proposed feature selection method significantly enhances the prediction accuracy by optimally selecting the features compared to the state of the art.
The 1960s Drought and the Subsequent Shift to a Wetter Climate in the Catskill Mountains Region of the New York City Watershed

AbstractThe precipitation history over the last century in the Catskill Mountains region that supplies water to New York City is studied. A severe drought occurred in the early to mid-1960s followed by a wet period that continues. Interannual variability of precipitation in the region is related to patterns of atmospheric circulation variability in the midlatitude east Pacific–North America–west Atlantic sector with no link to the tropics. Associated SST variations in the Atlantic are consistent with being forced by the anomalous atmospheric flow rather than being causal. In winter and spring the 1960s drought was associated with a low pressure anomaly over the midlatitude North Atlantic Ocean and northerly subsiding flow over the greater Catskills region that would likely suppress precipitation. The cold SSTs offshore during the drought are consistent with atmospheric forcing of the ocean. The subsequent wet period was associated with high pressure anomalies over the Atlantic Ocean and ascending southerl...
An Angle-Dependent Impedance Boundary Condition for the Split-Step Parabolic Equation Method

A formulation of the impedance boundary condition (IBC) is derived, which can be used in split-step parabolic wave equation solvers to accurately represent an interface with arbitrary dielectric properties. The approach relies on ensuring that the plane-wave decomposition of the field satisfies the appropriate IBC for each spectral component. Numerical experiments illustrating the robustness of the approach for low-contrast interfaces and angles-of-incidence near the Brewster angle are presented.
CBT with Youth: Immodest Proposals for Training the Next Generation

January 2014 brings the inauguration of the Affordable Care Act (ACA) in the United States. The ACA introduces affordable healthcare to all citizens and proposes a system to hold all healthcare providers accountable for quality treatment. This article discusses differences in the new healthcare climate and highlights specific areas of focus for training child clinicians in CBT in the midst of this evolution. Child clinicians, more than ever, will need a sound foundation of CBT theory and training so that they may fluidly practice and apply core principles in any setting, with any intervention. Transformations to the health care arena brought about by the ACA will see doctoral level clinicians practicing in a wider variety of roles, in highly integrated settings, and with an increasingly diverse population. Ability to ground intervention in solid theoretical framework will enable clinicians to practice in these numerous conditions effectively and meet accountability standards set by the ACA. Arming child clinicians with these skills will create a generation of practitioners well-prepared to care for youth in the developing atmosphere of mental health care in the United States.
Group theory: students' artistic visualizations†

Students in an introductory abstract algebra course often struggle with the basic concept of a group. I present an art project I assigned to my students to help address this challenge in which they were asked to visualize a group in an artistic medium of their choice. The resulting art was often pleasing to my eye and revealed the aspects of the structure of the depicted group. † Contributing Student Artists: Andrew Yau, Lauren Stein, Rachel Crossno, Richard Langford and Sabrina Schmidt.
Interpositional carotid artery bypass strategies in the surgical management of aneurysms and tumors of the skull base

Cerebral revascularization is an important component in the surgical management of complex skull base tumors and aneurysms. Patients who harbor complex aneurysms that cannot be clipped directly and in whom parent vessel occlusion cannot be tolerated may require cerebrovascular bypass surgery. In cases in which skull base tumors encase the carotid artery (CA) and a resection is desired, a cerebrovascular bypass may be necessary in planned CA occlusion or sacrifice. In this review the authors discuss options for performing high-flow anterograde interposition CA bypass for lesions of the skull base. The authors review three important bypass techniques involving saphenous vein grafts: the cervical-to-petrous internal carotid artery (ICA), petrous-to-supraclinoid ICA, and cervical-to-supraclinoid ICA bypass. These revascularization techniques are important tools in the surgical treatment of complex aneurysms and tumors of the skull base and cavernous sinus.
The LSST camera overview: design and performance

The LSST camera is a wide-field optical (0.35-1μm) imager designed to provide a 3.5 degree FOV with 0.2 arcsecond/pixel sampling. The detector format will be a circular mosaic providing approximately 3.2 Gigapixels per image. The camera includes a filter mechanism and shuttering capability. It is positioned in the middle of the telescope where cross-sectional area is constrained by optical vignetting and where heat dissipation must be controlled to limit thermal gradients in the optical beam. The fast f/1.2 beam will require tight tolerances on the focal plane mechanical assembly. The focal plane array operates at a temperature of approximately -100°C to achieve desired detector performance. The focal plane array is contained within a cryostat which incorporates detector front-end electronics and thermal control. The cryostat lens serves as an entrance window and vacuum seal for the cryostat. Similarly, the camera body lens serves as an entrance window and gas seal for the camera housing, which is filled with a suitable gas to provide the operating environment for the shutter and filter change mechanisms. The filter carousel accommodates 5 filters, each 75 cm in diameter, for rapid exchange without external intervention.
Identification of a brefeldin A-insensitive guanine nucleotide-exchange protein for ADP-ribosylation factor in bovine brain.

Abstract ADP-ribosylation factors (ARFs) are approximately 20-kDa guanine nucleotide-binding proteins that participate in vesicular transport in the Golgi and other intracellular compartments and stimulate cholera toxin ADP-ribosyltransferase activity. ARFs are active in the GTP-bound form; hydrolysis of bound GTP to GDP, possibly with the assistance of a GTP hydrolysis (GTPase)-activating protein results in inactivation. Exchange of GDP for GTP and reactivation were shown by other workers to be enhanced by Golgi membranes in a brefeldin A-sensitive reaction, leading to the proposal that the guanine nucleotide-exchange protein (GEP) was a target of brefeldin A. In the studies reported here, a soluble GEP was partially purified from bovine brain. Exchange of nucleotide on ARFs 1 and 3, based on increased ARF activity in a toxin assay and stimulation of binding of guanosine 5'-[gamma-[35S]thio]triphosphate, was dependent on phospholipids, with phosphatidylserine being more effective than cardiolipin. GEP appeared to increase the rate of nucleotide exchange but did not affect the affinity of ARF for GTP. Whereas the crude GEP had a size of approximately 700 kDa, the partially purified GEP behaved on Ultrogel AcA 54 as a protein of 60 kDa. With purification, the GEP activity became insensitive to brefeldin A, consistent with the conclusion that, in contrast to earlier inferences, the exchange protein is not itself the target of brefeldin A.
CHEMICALLY-INDUCED ALTERATIONS IN THE BEHAVIORAL EFFECTS OF LSD-25.

Abstract When LSD-25 is administered to rats trained to press a bar for food, a dose-dependent period of no responding occurs. After pretreatment with reserpine, tetrabenazine, or tranylcypromine and after recovery from behavioral effects of these compounds, the response to ED 90 or threshold doses of LSD-25 was markedly enhanced. Such effects were correlated with a change in levels of brain serotonin and norepinephrine; i.e., they occurred 5 hr after tetrabenazine when the amines were only 12% to 14% below normal. Fifteen mg benzquinamide/kg affected neither the LSD-25 response nor the levels of amines, whereas 30 μg chlorpromazine/kg attenuated the effect of 130 μg LSD-25/kg. The relationship of these findings to mechanisms regulating brain amines is discussed.
Approaches to consistency adjustment

Saaty's proposals for deriving a consistent ranking from a reciprocal matrix have generated a lively debate. This paper distinguishes between inference and description in consistency adjustment, offers an interpretation and a critique of the eigenvalue method of consistency adjustment, and discusses properties of the methods of weighted least squares and least lines, through which certain types of constraints may easily be imposed on the ranking.
Pedal and knee loads using a multi-degree-of-freedom pedal platform in cycling

To provide a scientific basis for the design of bicycle pedals which possibly alleviate over-use knee injuries, two hypotheses were tested in the present study. The two hypotheses were: (1) that the three-dimensional pedal constraint loads; and (2) that the three-dimensional intersegmental knee loads would be reduced more significantly by a foot/pedal platform allowing both adduction/abduction and inversion/eversion rotations simultaneously than by a platform which allowed either rotation individually. To test these hypotheses, pedal load and lower limb kinematic data were collected from 10 subjects who pedaled with four pedal platforms which allowed zero, one, and two degrees of freedom. A number of quantities describing both pedal loads and intersegmental knee loads was computed for each of the four pedal platforms using a previously reported biomechanical model. The quantities included the positive and negative extremes, averages, and areas, as well as the total absolute area and RMS. Quantities were compared using analysis of variance techniques. The key results were that there were significant reductions in the coupled nondriving moments at the pedal for the dual-rotation platform compared to each of the single-rotation cases. The significant reductions in the coupled moments at the pedal were not manifest at the knee. However, a general nonsignificant reduction in both coupled knee moments was evident. Also, the valgus knee moment was significantly reduced by the dual-rotation platform compared to the inversion/eversion only design. Although the axial knee moment was not significantly reduced by the dual-rotation platform over the adduction/abduction design, there was a general nonsignificant reduction. The lack of significance in knee load results occurred because of high intersubject variability. Accordingly, load reduction benefits made by introducing the second degree of freedom need to be considered individually.
Dual Mechanisms of Nucleophilic Substitution of Thiamin Analogs: Estimating the Special Kinetic Effect of Sulfite Ion

Abstract The thiamin derivative 4-amino-5-bromomethyl-l,2-dimethylpyrimidinium bromide (2a) reacts with p -nitrobenzenethiolate, thiosulfate, and azide ions and the corresponding 5-chloromethyl derivative, 2b , reacts with thiosulfate and azide ions, each substrate by an S N 2 mechanism. Large kinetic leaving group effects ( k Br / k Cl > 30) are found with thiosulfate and aside ions but not with sulfite ion. With sulfite ion 2a reacts by two competing mechanisms, mainly nucleophilic substitution by the unique multistep S N (AE) route found for thiamin and many of its analogs and also by a competing S N 2 mechanism. A linear free energy relationship comparing the reactivities of 2a and benzyl bromide toward a series of nucleophiles shows that the rate acceleration for the S N (AE) route over that for the S N 2 pathway is negligible for 2a and sulfite ion.
Targeted isolation, sequence analysis, and physical mapping of nonTIR NBS-LRR genes in soybean.

Most cloned plant disease resistance genes (R-genes) code for proteins belonging to the nucleotide binding site (NBS) leucine-rich repeat (LRR) superfamily. NBS-LRRs can be divided into two classes based on the presence of a TIR domain (Toll and interleukin receptor-like sequence) or a coiled coil motif (nonTIR) in their N-terminus. We used conserved motifs specific to nonTIR-NBS-LRR sequences in a targeted PCR approach to generate nearly 50 genomic soybean sequences with strong homology to known resistance gene analogs (RGAs) of the nonTIR class. Phylogenetic analysis classified these sequences into four main subclasses. A representative clone from each subclass was used for genetic mapping, bacterial artificial chromosome (BAC) library screening, and construction of RGA-containing BAC contigs. Of the 14 RGAs that could be mapped genetically, 12 localized to a 25-cM region of soybean linkage group F already known to contain several classical disease resistance loci. A majority of the genomic region encompassing the RGAs was physically isolated in eight BAC contigs, together spanning more than 1 Mb of genomic sequence with at least 12 RGA copies. Phylogenetic and sequence analysis, together with genetic and physical mapping, provided insights into the genome organization and evolution of this large cluster of soybean RGAs.
Proton dipole form factor quark model

The dipole-shaped electromagnetic form factors of the proton may imply an exponential radial dependence of the wave function describing the charged constituents of the proton. The hypercentral potential required by the three-body Dirac equation to produce such an exponential radial wave function for three bound quarks is found to have a linear confining potential plus an attractive Coulombic central diagonal part. The configuration assumed for the quark constituents is the (1/2+)3 positive parity configuration, coupled to the spin of the proton. Assuming equal-mass Dirac quarks with no anomalous magnetic moments, we find the largest magnetic moment for this wave function to be 2.763 nuclear magnetons, close to, but less than the experimental value of 2.793. The hypercentral potential is mostly the sum of three quark-quark potentials, but a small three-body potential is required.
Variations in Nursing Care Quality across Hospitals

Title. Variations in nursing care quality across hospitals. Aims. The aim of the study was to describe Registered Nurses’ reports of unmet nursing care needs and examine the variation of nursing care quality across hospitals. Background. Large proportions of Registered Nurses have reported leaving necessary care activities undone because they lacked the time to complete the activities. Nursing care left undone can be expected to adversely affect the quality of care. However, little is known about the degree of variation in the quality of nursing care across hospitals. Methods. In 2008, a secondary analysis of a 1999 survey of Registered Nurses (n = 10,184) was conducted using descriptive and comparative statistics. Data were derived from inpatient staff nurses working in acute care hospital settings (n = 168). A hospital-level measure (i.e. unmet nursing care needs) of the quality of nursing care was developed from care needs left undone among all nurses. Results. Across hospitals there was a wide range in the proportion of Registered Nurses who reported leaving each nursing care need undone. They reported leaving two of seven necessary nursing care activities undone during their last shift. After controlling for nurses’ demographic information, we found statistically significant variations in the quality of nursing care across hospitals. Conclusion. Differences in nursing care quality across hospitals appear to be closely associated with variations in the quality of care environments. Understanding the determinants of unmet nursing care needs can support policy decisions on systems and human resources management to enhance nurses’ awareness of their care practices and the care environment.
Domain motion and threshold behavior of charge-density waves

The relationship between the various computer-simulation theories of charge-density-wave motion is discussed, and some new simulation results in one and three dimensions are presented, which provide evidence that the motion near threshold proceeds by domains analogous to the Lee-Rice domains becoming unstable and jumping rapidly. The consequences of a model based on this picture are then discussed. This model leads to a threshold field which is different from the Lee-Rice depinning field (which is argued to be the field necessary to depin a typical domain but not necessarily sufficient to cause sustained motion of the charge-density wave), for strong pinning.
Ventricular standstill after intravenous diphenylhydantoin

Abstract A patient who suffered a cardiac arrest after rapid intravenous injection of diphenylhydantoin is presented. Slow infusion and careful monitoring of both the electrocardiogram and the blood pressure are mandatory when diphenylhydantoin is employed intravenously as an antiarrhythmic agent.
Novel spherical assembly of gold nanoparticles mediated by a tetradentate thioether.

The ability to construct three- and two-dimensional architectures via nanoscale engineering is important for emerging applications of nanotechnology in sensors, catalysis, controlled drug delivery,...
Amphetamine-modified acoustic startle responding and prepulse inhibition in adult and adolescent alcohol-preferring and -nonpreferring rats

Selective breeding has been used to develop the alcohol-preferring (P) and -nonpreferring (NP) rats, with the P rat having lower CNS levels of dopamine (DA) and reduced DA innervation in the nucleus accumbens compared with the NP rat. The acoustic startle response (ASR) and prepulse inhibition (PPI) of the ASR are experimental behaviors altered by DA agonists. We examined whether functional differences in amphetamine (AMPH)-modified ASR and PPI exist between P and NP rats. AMPH [0.0 (saline), 1.0, 2.0, or 4.0 mg/kg] was injected 15 min prior to placement into a startle apparatus. After a 5-min habituation period, rats were given approximately twelve 95-, 105-, or 115-dB white-noise burst (ASR) and PPI trials. As adults, P rats were sensitive to AMPH potentiation of the ASR to a greater extent than NP rats. During adolescence, P and NP rats had similar levels of AMPH-potentiated ASR. As adults, NP rats displayed potentiated, rather than disrupted, PPI at the 1.0-mg/kg dose, whereas P rats displayed the expected disrupted PPI at the 4.0-mg/kg dose. As adolescents, NP rats did not display significant differences in PPI after AMPH, whereas P rats displayed dose-dependent disruption of PPI, which was significant at the 4.0-mg/kg dose. The limited effect of AMPH on increasing the ASR and the presence of AMPH-potentiated PPI at the lowest dose in the adult NP rat suggests reduced functioning of the interactions between DA circuits and the neurocircuitry mediating the ASR and PPI, compared with P rats. However, the neurocircuitry mediating PPI does not appear to be fully developed in the adolescent NP rat. The present findings also indicate that lower levels of DA content and immunoreactive fibers in the P rat may not reflect reduced DA neuronal activity, because the P rat displayed AMPH-potentiated ASR, and, at the highest dose, AMPH disruption of PPI during both adulthood and adolescence.
Aberrant Time to Most Recent Common Ancestor as a Signature of Natural Selection

Natural selection inference methods often target one mode of selection of a particular age and strength. However, detecting multiple modes simultaneously, or with atypical representations, would be advantageous for understanding a population’s evolutionary history. We have developed an anomaly detection algorithm using distributions of pairwise time to most recent common ancestor (TMRCA) to simultaneously detect multiple modes of natural selection in whole-genome sequences. As natural selection distorts local genealogies in distinct ways, the method uses pairwise TMRCA distributions, which approximate genealogies at a nonrecombining locus, to detect distortions without targeting a specific mode of selection. We evaluate the performance of our method, TSel, for both positive and balancing selection over different time-scales and selection strengths and compare TSel’s performance with that of other methods. We then apply TSel to the Complete Genomics diversity panel, a set of human whole-genome sequences, and recover loci previously inferred to be under positive or balancing selection.
A structure approach to code correspondence analysis

Results from a code correspondence analysis task for the trusted computing base of an internet gateway system are reported. Analysis placement within the context of the overall assurance demonstration for the system is described, and the definition and employment of a method to increase the credibility of the code correspondence effort as compared with previous efforts are discussed. The method described is a refinement of the approach promulgated by a US Department of Defense standard. The integrated assurance demonstration approach is presented in a manner that is applicable to requirements that may be identified as critical, though not necessarily security related. The results obtained from applying specific techniques that make the integrated assurance demonstration real within a development project are summarized. >
The role and suppression of carrier leakage in 1.5 /spl mu/m GaInNAsSb/GaAs lasers

Recently, the first room temperature, continuous wave (CW), 1.49 /spl mu/m GaAs-based lasers were demonstrated. The injection efficiency, /spl eta//sub inj/, was quite low in these devices, /spl sim/45%. Determining the origin of the low /spl eta//sub inj/ allows further improvements in device performance. The origin of the low /spl eta//sub inj/ is due to carrier leakage and nonradiative recombination. In this paper, several techniques are proposed to reduce this defect-enhanced electron leakage mechanism, including a novel asymmetric quantum well structure.
Behavioral and mechanical determinants of collective subsurface nest excavation.

Collective construction of topologically complex structures is one of the triumphs of social behavior. For example, many ant species construct underground nests composed of networks of tunnels and chambers. Excavation by these ‘superorganisms’ depends on the biomechanicsofsubstratemanipulation,theinteractionofindividuals, and media stability and cohesiveness. To discover principles of robust social excavation, we used X-ray computed tomography to monitor the growth in three dimensions of nests built by groups of fire ants (Solenopsis invicta) in laboratory substrates composed of silica particles, manipulating two substrate properties: particle size and gravimetric moisture content. Ants were capable of nest construction in all substrates tested other than completely dry or fully saturated; for a given particle size, nest volume was relatively insensitive to moisture content. Tunnels were deepest at intermediate moisture content and the maximum tunnel depth correlated with measured yield force on small rod-shaped intruders (a proxy for cohesive strength). This implies that increased cohesive strength allowed creation of tunnels that were resistant to perturbation but did not decrease individual excavation ability. Ants used two distinct behaviors to create pellets composed of wetted particles, depending on substrate composition. However, despite the ability to create larger stable pellets in more cohesive substrates, pellet sizes were similar across all conditions. We posit that this pellet size balances the individual’s load-carrying ability with the need to carry this pellet through confined crowded tunnels. We conclude that effective excavation of similarly shaped nests can occur in a diversity of substrates through sophisticated digging behaviors by individuals which accommodate both differing substrate properties and the need to work within the collective.
Hot filament assisted diamond growth at low temperatures with oxygen addition

Addition of a small amount of oxygen to the CH{sub 4} and H{sub 2} feed gas permits hot filament assisted chemical vapor deposition (HFCVD) of diamond at significantly lower filament and substrate temperatures. The former can be reduced to as low as 1400{degree}C and the latter to 450{degree}C. The amount of oxygen required is much lower than what has been used in most studies of the oxygen effect. For each CH{sub 4}{percent}, there is a narrow window in the O/C ratio, where diamond can be deposited at low temperature. This window shifts to higher O/C ratios as the CH{sub 4}{percent} increases and expands with increases in filament temperature. The effects of changing substrate and filament temperatures on growth rate and film quality are often not consistent with previous experiences with HFCVD of diamond. Increasing the filament temperature does not always improve the growth rate and film quality, and the non-diamond carbon content in the film is dramatically reduced at lower substrate temperatures. Optimum conditions were found that gave reasonable growth rates ({approximately}0.5{mu}m/h) with high film quality at filament temperatures below 1750{degree}C and substrate temperatures below 600{degree}C. With these reductions in operating temperatures, power consumption can be significantly reduced and themore » filament lifetime extended indefinitely. {copyright} {ital 1997 Materials Research Society.}« less
Evidence-based management of hyperglycemic emergencies in diabetes mellitus

The hyperglycemic emergencies, diabetic ketoacidosis (DKA) and hyperglycemic hyperosmolar state (HHS) are potentially fatal complications of uncontrolled diabetes mellitus. The incidence of DKA and the economic burden of its treatment continue to rise, but its associated mortality rate which was uniformly high has diminished remarkably over the years. This Improvement in outcome is largely due to better understanding of the pathogenesis of hyperglycemic emergencies and the application of evidence-based guidelines in the treatment of patients. In this article, we present a critical review of the evidence behind the recommendations that have resulted in the improved prognosis of patients with hyperglycemic crises. A succinct discussion of the pathophysiology and important etiological factors in DKA and HHS are provided as a prerequisite for understanding the rationale for the effective therapeutic maneuvers employed in these acute severe metabolic conditions. The evidence for the role of preventive measures in DKA and HHS is also discussed. The unanswered questions and future research needs are also highlighted.
Centrin1 is required for organelle segregation and cytokinesis in Trypanosoma brucei

Centrin is a calcium-binding centrosome/basal body–associated protein involved in duplication and segregation of these organelles in eukaryotes. We had shown that disruption of one of the centrin genes (centrin1) in Leishmania amastigotes resulted in failure of both basal body duplication and cytokinesis. Here, we undertook to define the role of centrin1 (TbCen1) in the duplication and segregation of basal body and its associated organelles kinetoplast and Golgi, as well as its role in cytokinesis of the procyclic form of Trypanosoma brucei by depleting its protein using RNA inhibition methodology. TbCen1-depleted cells showed significant reduction in growth compared with control cells. Morphological analysis of these cells showed they were large and pleomorphic with multiple detached flagella. Both immunofluorescence assays using organelle-specific antibodies and electron microscopic analysis showed that TbCen1-deficient cells contained multiple basal bodies, kinetoplasts, Golgi, and nuclei. These multiple organelles were, however, closely clustered together, indicating duplication without segregation in the absence of centrin. This failure in organelle segregation may be the likely cause of inhibition of cytokinesis, suggesting for the first time a new and unique role for centrin in the segregation of organelles without affecting their multiplication in the procyclic form of T. brucei.
Robust, Efficient, Globally-Optimized Reinforcement Learning with the Parti-Game Algorithm

Parti-game (Moore 1994a; Moore 1994b; Moore and Atkeson 1995) is a reinforcement learning (RL) algorithm that has a lot of promise in overcoming the curse of dimensionality that can plague RL algorithms when applied to high-dimensional problems. In this paper we introduce modifications to the algorithm that further improve its performance and robustness. In addition, while parti-game solutions can be improved locally by standard local path-improvement techniques, we introduce an add-on algorithm in the same spirit as parti-game that instead tries to improve solutions in a non-local manner.
Home, Sweet Home: American Residential Zoning in Comparative Perspective

This paper explores the emergence of zoning in early twentieth-century America against the background of zoning in two European countries: Germany and England. The common interpretation is that zon...
Should health plans be accountable for clinical performance measures

The concept of managed care is pretty straightforward: maximize value of economic resources assembled to provide services for a population of patients. In addition to prudent management of financial capital, managed care companies need to develop networks of providers and coordinate benefits to facilitate effective and efficient health care for its enrollees. These tasks, in and of themselves, are not always guaranteed to run efficiently and effectively when a company opens up for new business. Clearly, some managed care companies may simply be more effective at structuring its programs than competitors. Because managed care programs in the United States are frequently connected with employer health insurance programs, purchasers of health insurance have pressed the industry to develop benchmarks to document effective care of patients whose employment related premiums sustain the economic enterprise. Thus, formal measurement systems such as HEDIS from the National Committee on Quality Assurance have evolved to provide benchmarks of performance to compare plans. Increasingly, such performance measurement is made publicly available to all participants and stakeholders in the health care system [1]. Nevertheless, it remains an open question as to whether health plans themselves have a real impact upon these performance measures. Since …
Variable differential-group-delay module without second-order PMD

We propose a design for a variable differential-group-delay (DGD), formed by concatenation of four identical fixed DGD segments. Due to the symmetry involved, it produces zero second-order polarization mode dispersion (PMD). The generated third-order PMD is half the value of the conventional two-segment concatenation for variable DGD.
A mechanism for masking receptors with particular application to asthma.

Abstract This study ensconces the concept currently popular in neurophysiology that nerve terminals can be sensitized by'unmasking' more receptors, but goes on to propose that the unknown substance masking the remainder is surface-active phospholipid. These molecules are considered to bind reversibly by adsorption to receptor surfaces just as they are known to do at a variety of tissue surfaces at which they impart ‘barrier’ properties very similar to those much exploited in the physical sciences. This model of nonspecific adsorption is further extended to a wide variety of receptors in lung airways including those on smooth muscle, to explain the normal control of sensitivity of reflex bronchoconstriction indicated by many physiological features. In the corollary hypothesis, asthma is attributed to a basic deficiency in surfactant causing undue unmasking of receptors exposed to the next noxious stimulus to enter the lungs. This model is shown to be compatible with the actions of a very wide variety of sensitizing agents which are physical, chemical and biological in nature; while the inflammation arising from the more biological routes can be correlated according to whether they release surfactant or disrupt it. Special attention is focused upon the diverse actions of nonsteroidal anti-inflammatory drugs versus steroids widely prescribed for asthma which promote the secretion of surfactant, as do the popular β-agonists.
Hydrological Monitoring with Hybrid Sensor Networks

Existing hydrological monitoring systems suffer from shortcomings in accuracy, resolution, and scalability. Their fragility, high power consumption, and lack of autonomy necessitate frequent site visits. Cabling requirements and large size limit their scalability and make them prohibitively expensive. The research described in this paper proposes to alleviate these problems by pairing high-resolution in situ measurement with remote data collection and software maintenance. A hybrid sensor network composed of wired and wireless connections autonomously measures various attributes of the soil, including moisture, temperature, and resistivity. The measurements are communicated to a processing server over the existing GSM cellular infrastructure. This system enables the collection of data at a scale and resolution that is orders of magnitude greater than any existing method, while dramatically reducing the cost of monitoring. The quality and sheer volume of data collected as a result will enable previously infeasible research in hydrology.
Mood, motivation, and misinformation: Aging and affective state influences on memory

Normative age differences in memory have typically been attributed to declines in basic cognitive and cortical mechanisms. The present study examined the degree to which dominant everyday affect might also be associated with age-related memory errors using the misinformation paradigm. Younger and older adults viewed a positive and a negative event, and then were exposed to misinformation about each event. Older adults exhibited a higher likelihood than young adults of falsely identifying misinformation as having occurred in the events. Consistent with expectations, strength of the misinformation effect was positively associated with dominant mood, and controlling for mood eliminated any age effects. Also, motivation to engage in complex cognitive activity was negatively associated with susceptibility to misinformation, and susceptibility was stronger for negative than for positive events. We argue that motivational processes underlie all of the observed effects, and that such processes are useful in understanding age differences in memory performance.
Velocity–depth ambiguity and the seismic structure of large igneous provinces: a case study from the Ontong Java Plateau

SUMMARY The seismic structure of large igneous provinces provides unique constraints on the nature of their parental mantle, allowing us to investigate past mantle dynamics from present crustal structure. To exploit this crust–mantle connection, however, it is prerequisite to quantify the uncertainty of a crustal velocity model, as it could suffer from considerable velocity–depth ambiguity. In this contribution, a practical strategy is suggested to estimate the model uncertainty by explicitly exploring the degree of velocity–depth ambiguity in the model space. In addition, wide-angle seismic data collected over the Ontong Java Plateau are revisited to provide a worked example of the new approach. My analysis indicates that the crustal structure of this gigantic plateau is difficult to reconcile with the melting of a pyrolitic mantle, pointing to the possibility of large-scale compositional heterogeneity in the convecting mantle.
Incomplete Urethral Duplication and Urinary Retention

Summary Three boys with incomplete urethral duplication and urinary retention are reported. The mechanism of retention is discussed and operative correction by marsupialisation of both channels and subsequent urethroplasty described.