cssi/SciSciGPT-SciSciNet huggingface dataset:
Perturbed structure of molecular hydrogen near the second dissociation limit.

The region of the second dissociation limit of H{sub 2} converging to H(1{ital s})+H(2{ital s},2{ital p}) has been investigated using high-resolution double-resonance spectroscopy through the {ital E},{ital F} {sup 1}{Sigma}{sub {ital g}}{sup +} state. Transitions to the very high vibrational levels of the {ital B} {sup 1}{Sigma}{sub {ital u}}{sup +}, {ital B}{prime} {sup 1}{Sigma}{sub {ital u}}{sup +}, and {ital C} {sup 1}{Pi}{sub {ital u}} states have been measured with 0.02-cm{sup {minus}1} accuracy. Numerous perturbations and unexpected transitions are observed as far as 10 cm{sup {minus}1} below the dissociation limit. This complex structure, still not fully understood, arises from a combination of electronic, fine-structure, and hyperfine interactions.
Physiological arousal in the context of a specified anticipatory period and experimentally induced expectancy for shock

Abstract Anticipatory and reactive components of skin conductance and heart rate were assessed under different levels of shock expectancy. Sixty college males received two shock and two nonshock trials of a 12-light count-up where shock occurred at the eighth light. Expectancies were experimentally induced via 20 preliminary trials during which a red light substituted for shock. The red light appeared on 18 20 , 10 20 , and 2 20 preliminary trials for 90, 50, and 10% expectancy groups, respectively. Prior to each test trial, subjects estimated the likelihood of receiving shock. Major findings were that: (a) mean probability estimates corresponded closely with values provided by preliminary trials; (b) tonic skin conductance during anticipation was higher with greater expectancy for shock; (c) phasic change in skin conductance to the count-up lights was greatest in the 90% group during anticipation; and (d) reactivity at impact tended to be greater with higher anticipatory arousal. The relationship of event probability to stress was discussed with respect to length of the anticipatory periods and methods used to establish expectancies.
Radiation damping of autoionizing resonances

Radiative decay of resonances is investigated in detail for electron - ion recombination cross sections of He-like ions of carbon and iron. Relativistic close-coupling calculations are carried out using the Breit - Pauli R-matrix method, combined with a perturbative treatment for radiative and autoionization decay, as well as with the relativistic distorted-wave method. Good agreement is found with the synchrotron-storage ring experimental data for C V by Mannervik et al, and the electron-beam ion-trap data for Fe XXV by Beiersdorfer et al. Radiation damping is considerably more significant for Fe XXV than C V; however, contrary to claims by Gorczyca and Badnell and Robicheaux et al, it is unlikely to be of importance in general since the radiative decay rates are orders of magnitude smaller in atomic species other than the He-like and the H-like ions.
Linking trade and external debt strategies

Abstract Despite the productive inefficiencies generated by policies of export promotion and of import substitution, such development strategies can improve welfare when used in conjunction with a debt strategy. Export promotion can increase the availability of foreign finance, and import substitution can reduce debt service. When the latter strategy is optimal, partial debt forgiveness increases the creditor group's payoff. Import substitution is more profitable with a large inherited debt, high world interest rate, low terms of trade, and when creditors fail to reduce inherited debt.
Analysis of the interaction of a laser pulse with a silicon wafer - Determination of bulk lifetime and surface recombination velocity

The decay of excess minority carriers produced in a silicon wafer of thickness d by a laser pulse is analyzed. A comprehensive theory based on this analysis is presented for the determination of bulk lifetime Tau(b) and surface recombination velocity S. It is shown that, starting with an exponential spatial profile, the carrier profile assumes a spatially symmetrical form after approximately one time constant of the fundamental mode of decay. Expressions for the spatial average of the carrier density as a function of time are derived for three temporal laser pulse shapes: impulse, square, and Gaussian. Particular attention is paid to the time constants of the fundamental and higher modes of decay. The ratios of the time constants of the higher modes to the fundamental mode, as well as the time constant of the fundamental mode, are presented over wide ranges of values of S and d. For Sd less than about 40 sq cm/s, a two-wafer method is developed to determine Tau(b) and S; it is also shown that the requirement of d/Tau(b) greater than about 20S is sufficient to adequately guarantee that the asymptotic value of the instantaneous observed lifetime differs from the bulk lifetime by no more than 10 percent.
Understanding the impacts of integrating New Urbanist neighborhood and street design ideals with conventional traffic engineering standards: the case of Stapleton

This research considers the implications of building places that possess many of the qualities that make New Urbanism so desirable but also marginalizing them with other qualities that prioritize automobility to meet the demands of conventional traffic engineering standards. By examining the existing built environment of Stapleton – a New Urbanist development in Denver, Colorado – in terms of street network characteristics, street designs, and intersection designs, I investigate the inconsistencies of the resulting built environment with respect to the latest research and state-of-the-practice New Urbanism design ideals. The outcomes are then considered in terms of how people actually use the transportation system by way of vehicle speed studies and travel diaries. The trends suggest that mixing New Urbanist neighborhood and street design characteristics with conventional traffic engineering standards results in travel behaviors more consistent with conventional auto-oriented developments.
Justifications for a hybrid approach to optical computing

A hybrid approach to optical computing is currently studied at the University of California, San Diego for performing parallel processing. Figure 1 shows a promising parallel processing architecture, in which an optical processing array is connected massively in parallel to an optical memory array. An optical processing array consists of an array of electronic logic gates; each cell in the array has at least one photodetector (or phototransistor) and one modulator for optical input/output. Similarly, an optical memory array consists of an array of electronic memory circuits; each cell in the array has also optical input/output. Within the optical processing array or the optical memory array, local interconnections among neighboring cells can be established electronically. Between the optical processing array and the optical memory array, global interconnections among distant cells can be established optically using the optical input/output in each cell. One important application of such a massively interconnected architecture would be to perform matrix-tensor multiplications (Ref. 1) not only for numeric computing, but also for artificial intelligence and neural computing (Ref. 2). There are three unique aspects associated with the parallel architecture of Figure 1, which may serve to justify this hybrid approach toward optical computing: optical interconnection, 3-D computational topology and optical memory.
Learning to detect events with Markov-modulated poisson processes

Time-series of count data occur in many different contexts, including Internet navigation logs, freeway traffic monitoring, and security logs associated with buildings. In this article we describe a framework for detecting anomalous events in such data using an unsupervised learning approach. Normal periodic behavior is modeled via a time-varying Poisson process model, which in turn is modulated by a hidden Markov process that accounts for bursty events. We outline a Bayesian framework for learning the parameters of this model from count time-series. Two large real-world datasets of time-series counts are used as testbeds to validate the approach, consisting of freeway traffic data and logs of people entering and exiting a building. We show that the proposed model is significantly more accurate at detecting known events than a more traditional threshold-based technique. We also describe how the model can be used to investigate different degrees of periodicity in the data, including systematic day-of-week and time-of-day effects, and to make inferences about different aspects of events such as number of vehicles or people involved. The results indicate that the Markov-modulated Poisson framework provides a robust and accurate framework for adaptively and autonomously learning how to separate unusual bursty events from traces of normal human activity.
Troglitazone-induced liver failure: A case study

Abstract Background Troglitazone was removed from the U.S. market because its use was associated with an increased risk of liver failure. We evaluated the clinical features of all cases reported to the Food and Drug Administration and estimated the duration and magnitude of the risk of liver failure associated with continued use of the drug. Methods Data from cases of liver failure associated with troglitazone use were abstracted and analyzed. The extent of troglitazone use was determined from national marketing data, and the duration of use was estimated with data from a large, multistate, health care company. Survival analysis was performed to estimate monthly incidence rates and the cumulative risk of liver failure. Results Ninety-four cases of liver failure (89 acute, 5 chronic) were reported. Of the acute cases, 58 (67%) were women and only 11 (13%) recovered without liver transplantation. Progression from normal hepatic functioning to irreversible liver injury occurred within 1 month in 19 patients who were indistinguishable clinically from the 70 patients who had an unknown time course to irreversibility, except for the post hoc observation that prior cholecystectomy was less common in those with rapid onset. The incidence of liver failure was elevated from the first through at least the 26th month of troglitazone use. Accounting for case underreporting, the number needed to harm from troglitazone use was between 600 to 1500 patients at 26 months. Conclusion The progression to irreversible liver injury probably occurred within a 1-month interval in most patients, casting doubt on the value of monthly monitoring of serum aminotransferase levels as a means of preventing troglitazone-induced acute liver failure. The cumulative risk of hepatic failure increased with continued use.
jMonitor: Java Runtime Event Specification and Monitoring Library

jMonitor is a pure Java library and runtime utility for specifying event patterns and associating them with user provided event monitors that get called when the specified runtime events occur during the execution of legacy Java applications. jMonitor APIs define an event specification abstraction layer allowing programmers to design event patterns to monitor runtime execution of legacy Java applications. jMonitor instrumentation works at the Java bytecode level and does not require the presence of source code for the Java application that is being monitored. jMonitor overloads the dynamic class loader and takes the event specification and monitors (in the form of Java class files) as additional arguments when launching the target Java application. The class bytecodes of the monitored Java program are instrumented on the fly by the jMonitor class loader according to the needs of the externally specified jMonitor event patterns and event monitors.
The physical metallurgy of titanium alloys

A brief review of titanium physical metallurgy is given and related to alloy development work based on modification of the Ti6Al4V alloy. Highlights of the alloy development work are given. Observations are made on the manner in which Ti3Al may contribute to seawater embrittlement and a possible direction for attaining yield strengths in the range 250–275, 000 psi is indicated.
Surface Segmental Mobility and Adhesion—Effects of Filler and Molecular Mass

The adhesion of thin films of poly(methyl acrylate) (PMA) on glass slides in contact with tape has been measured as a function of thickness, molecular mass, and amount of silica-based filler. In all cases studied the polymer thin-film, tape-peel tests resulted in linear force-velocity plots. The best-fit lines were extrapolated to find the fracture energies at zero velocity. For thin layers of rubbery PMA on glass slides the PMA-tape fracture energies were found to decrease (from 55–20 J/m2) with increasing PMA thickness (50–1000 nm). Thin films made from glassy poly(methyl methacrylate) (PMMA) were found to have no thickness dependence and much higher fracture energies (∼ 140 J/m2). The effect of PMA molecular mass was found to be smaller than the effect of film thickness. Including silica in the films at low levels dramatically increased the fracture energies, with a maximum (182 J/m2) found with 5.2% silica. With larger amounts of silica, the fracture energy declined significantly.
Covalent and noncovalent interactions of membrane proteins from the chick lens.

Bifunctional crosslinking reagents, in conjunction with diagonal electrophoresis, have been used to characterize nearest-neighbor interactions of membrane proteins from the chick lens. The Main Intrinsic Polypeptide (MIP) of 26 000 daltons is crosslinked into apparent homodimers by both the cupric-phenanthroline oxidizing reagent and by the lipophilic 4,4′-dithiobisphenylazide bifunctional reagent. In addition, a 30 k component is also linked via native disulfide bonding to a membrane component of 17 000 daltons. Analysis of radio-iodinated tryptic peptides indicates similar but not identical maps for the 30 k and 26 k peptides. Together, these results demonstrate that the 26 k and 30 k components are related membrane proteins that are both involved in extensive protein-protein interactions in the chick lens.
The motor units of cat medial gastrocnemius. Twitch potentiation and twitch-tetanus ratio.

Twitch potentiation and the associated changes in contraction time and 1/2 relaxation time have been studied in a sample of 78 medial gastrocnemius motor units from 8 cats. Potentiation was produced by repetitive stimulation of the motor units every 10 sec with a brief tetanus followed 2 sec later by a twitch. Fast twitch fatigue resistant units were found to potentiate more strongly than either slow twitch (contraction time >45 msec) or fast twitch fatigable units. It is concluded that Type C muscle fibres are more susceptible to potentiation than either Type A or Type B fibres. In a sample of 88 motor units from the same experiments, values for twitch/tetanus ratio were compared amongst units sharing similar mechanical properties. Slow contracting units developed small tetanic tensions and had small twitch/tetanus ratios. Fast twitch non fatigable units had intermediate values for contraction strength and twitch/tetanus ratio overlapping the ranges found for both the slow twitch and the more powerful fast twitch fatigable units. It is concluded that differences in twitch/tetanus ratio for medical gastrocnemius motor units are primarily related to motor unit contraction strength rather than differences in muscle fibre type.
An optimal single/concurrent link MAC scheme for a single-hop MIMO network

It is generally accepted that enabling concurrent links via the use of multi antenna techniques is an effective means of improving throughput in a MANET. Several MAC protocols (i.e. MIMA MAC, and SPACEMAC) have even been introduced in the literature specifically to increase the number of concurrent links. Recent work, however, has shown that this is not universally true. Given a MIMO enabled network, there are easily produced topologies where a single link MAC will outperform a concurrent MAC, which motivates the need for a MAC scheme that could choose between single link and concurrent link operation as the dynamics of the system changes. In this paper we present a novel MIMO MAC design that can adaptively switch between a single link scheme and a concurrent link scheme. Our design objective is to improve the link throughput by guaranteeing each link's throughput to be no less than that achievable via a single link MAC protocol. To demonstrate our design principle, we first present an idealized derivation where all network information is perfectly known at all nodes. Then as a realistic implementation, we further present a practical MAC protocol that uses distributed handshaking and imperfect channel estimation to run the adaptive switching function. Simulation results validate that our design's link throughput is greater than or equal to a single link MAC's throughput with 2% – 12% outage probabilities. Moreover, the proposed MAC's ergodic link throughput is 20%–30% higher than single link MAC and MIMA-MAC's counterparts.
Men's and women's attitudes and beliefs about the menstrual cycle

Recent analyses of menstrual distress have emphasized sociocultural influences. Yet beliefs and attitudes of men—an important socialization force in the lives of women—have received little attention. In the present study, 239 students (156 females and 83 males) from three colleges filled out a survey on expectations for menstrual and premenstrual symptoms, attitudes about mensturation, sources of menstrual-related information, and effects of menstruation upon daily activities. The major findings are as follows: First, although both males and females believed women experience certain cycle-related symptoms, females reported that women experience more severe menstrual and premenstrual symptoms (when compared to intermenstrual ones) than males reported, while males believed women experience more severe menstrual than premenstrual symptoms than females believed. Second, males learned less about menstruation from the majority of possible informational sources and rated most sources as more negative than did the females. Third, males believed that menstruation had more of an effect on women's moods and had a more debilitating effect on women's lives than did females. Fourth, females rated menstruation as more bothersome than did males. Fifth, more males believed their mothers experienced menstrual irritability and moodiness, while more females believed their mothers experienced swelling. The findings are discussed in terms of the role of socialization and the type of information imparted to males and females in America today.
Free-radical crosslinking copolymerization of styrene/unsaturated polyester resins: 1. Phase separation and microgel formation

Abstract An important feature of free-radical crosslinking copolymerization of styrene (ST)/unsaturated polyester (UPE) resins is the formation of a heterogeneous structure through strong intramolecular reactions and phase separation. Such structure formation affects not only the cure behaviour and rheological changes of the resin but also the physical properties of final products. In this study, the phase separation process was investigated by optical microscopy and time-resolved light scattering goniometry. Partially reacted samples of ST/UPE resin before macrogelation were also prepared by stopping the polymerization at preset times. The size and composition of primary polymers were determined using dynamic light scattering goniometry and Fourier transform infra-red spectroscopy.
Metallocene basicity. IV. Conformational and electronic behaviour of some protonated ferrocenes

Abstract The PMR spectra of several substituted ferrocenes in HBF3OH have been recorded and the metal protonated species are discussed. 1,3-di-t-butylferrocenonium compounds were found to exist as two noninterconverting rotamers in acid solution. Hammett substituent constants for ferrocene and ferrocenonium have been determined.
Apheresis in three dogs weighing <14 kg.

History CaridianBCT apheresis machines require a ~285 mL priming volume (extracorporeal blood) that is withdrawn from the patient in ~10 minutes. Therefore, apheresis in dogs has generally been limited to dogs >~ 20 kg to assure <20% of the blood volume is removed in the priming phase.
Non-adrenergic non-cholinergic relaxation of the rat stomach

1. Receptive and adaptive relaxations of the proximal third of the stomach are reflex responses that enable the stomach to accommodate large volumes with minimal increases in intraluminal pressure. The smooth muscle relaxations are termed non-adrenergic non-cholinergic (NANC). 2. Nitric oxide (NO) and vasoactive intestinal polypeptide (VIP) are considered to be the principal neurotransmitters of NANC relaxation of the rat stomach. NO appears to be mainly responsible for the speed of the relaxation and VIP appears to be responsible for the duration. 3. Studies indicate that inhibitory neurons may also release other neurotransmitters, such as adenosine triphosphate (ATP) and peptide histidine isoleucine (PHI). 4. NANC relaxation of the rat stomach is a complex phenomenon that appears to involve many neurotransmitters, each with a specific role.
Percutaneous endoscopic gastrostomy

Over the past 5 to 7 years, the veterinary profession has benefitted from our increased ability to provide nutrition to the small animal patient who cannot or will not eat. The adaptation of the percutaneous endoscopic gastrostomy (PEG) for use in the dog and cat deserves a great deal of credit in advancing the level of care we can now give to the chronically ill or critical care patient. The PEG is a relatively simple technique that has proved to be a very cost-efficient way to maintain the nutritional status of the small animal patient. In the author's experience, owner acceptance of using the PEG in the home environment on a chronic basis has been excellent.
Formation of Oxalacetate and Aspartate from Phospho-Enol-Pyruvate in Spinach Leaf Chloroplast Extract

WHILE investigating the ability of water extracts1 of spinach leaf chloroplasts to catalyse ‘dark’ carb-oxylation reactions, we have found that the addition of phospho-enol-pyruvate and 14CO2 to the colourless chloroplast extract causes the accumulation of labelled oxalacetate and labelled aspartate in the reaction mixture. Bandurski and Greiner2 using spinach leaves, Tchen and Vennesland3 using wheat germ and spinach leaves, and Utter et al. 4 using bird liver, have described enzyme preparations which catalyse irreversible and reversible carboxylations of phospho-enol-pyruvate to oxalacetate. The formation of oxalacetate in our experiments indicates the presence of a phospho-enol-pyruvate carboxylase in the chloroplast. Aspartate can then be formed by transamination of oxalacetate. The rate of carbon fixation was increased when, in addition to phospho-enol-pyruvate, either alanine, glutamine or aspartic acid was added to the reaction mixture.
Effect of Surface Chemistry on Mechanical Energy Dissipation: Silicon Oxidation Does Not Inherently Decrease the Quality Factor

The rate of energy dissipation in megahertz-range micromechanical silicon resonators is unaffected by the controlled oxidation of one-half monolayer of surface sites, thereby proving that silicon oxidation does not inherently decrease the quality factor (Q). Homogeneously mono-oxidized surfaces were prepared by the controlled reaction of dodecyl aldehyde with H-terminated silicon surfaces to form dodecoxy-terminated surfaces (C12H25O−Si). The existence of an approximately half monolayer of Si−O−R species (the maximum allowed by steric constraints) was confirmed by infrared spectroscopy. As a control, dodecyl-terminated surfaces (C12H25−Si) were prepared by the reaction of 1-dodecene with H-terminated surfaces. Infrared spectroscopy showed that the density and ordering of the alkyl chains on the dodecoxy- and dodecyl-terminated surfaces were nearly identical, and no subsurface oxidation was detected on either surface. Dodecoxy- and dodecyl-terminated resonators displayed similar quality factors both immedi...
Death as seen in books for young children

Abstract This paper summarizes and evaluates 22 children's books dealing with death in terms of their usefulness in helping 3-to 9-year-old children understand and cope with the concept of death. Included in the analysis are 12 books dealing with the death of an animal and 10 books dealing with the death of a person. Some of the books contain confusing references to abstract concepts such as linear time; living and nonliving; animate and inanimate; the finality, irreversibility, and universality of death; and religious ideas. Yet, except for one book on the death of a dog, all of the books treat the topic of death in a generally acceptable way by using direct and concrete words and avoiding euphemisms, involving the main characters in the funeral and at the cemetery, showing respect and acceptance of feelings, understanding the child's grieving process, explaining death in a positive way, and ending on a hopeful note with the main characters getting on with life.
Graphical calculation of waist-to-waist transfer in particle optics

Abstract A graphical method is described to calculate waist-to-waist transfer in the in-lens particle optics. Example are given to show the method would allow one to a design a beam line great speed and reasonbale precision.
Bioactivity of echinoderm ethanolic body-wall extracts: an assessment of marine bacterial attachment and macroinvertebrate larval settlement

The ethanolic body-wall extracts of 16 species of echinoderms from 16 genera were screened for their ability to affect the attachment of the marine bacteria Deleya marina (Baumann) and Alteromonas luteo-violacea (Gauthier). Body-wall extracts were tested at concentrations which mimic mean natural tissue concentration, 3.0 mg/ml seawater, and four half-log dilutions of this initial concentration. The extracts of three echinoderm species caused significant inhibition of bacterial attachment, while extracts of eight species caused significant enhancement of attachment. The body-wall extract of the asteroid Goniaster tesselatus (Lamarck) displayed the most potent antimicrobial activity, completely inhibiting attachment of both bacterial species at a concentration of 3.0 mg/ml seawater. The ethanolic extracts of 20 echinoderm species were also tested at a similar range of concentrations for their ability to affect the settlement of cyprid larvae of the barnacle Balanus amphitrite (Darwin), and coronate larvae of the bryozoan Bugula neritina (Linne). All echinoderm extracts inhibited settlement of both barnacle and bryozoan larvae at the highest concentration tested (3.0 mg/ml seawater). Eleven of the 20 echinoderms tested (13 asteroids, 3 holothuroids, 3 ophiuroids and a crinoid) had body-wall extracts that inhibited settlement of competent barnacle and bryozoan larvae at concentrations as low as 0.12 mg/ml seawater. These extracted echinoderm compounds may function as non-toxic or toxic antifoulants, and to promote bacterial surface colonization, which could be valuable to the organisms disease resistance.
Pattern classification via linear programming

Abstract This paper presents a linear programming-based pattern classification method that is completely nonparametric and algorithmic. The proposed method can be used for any classification problem, regardless of the number of classes, the dimensionality of a feature vector, or the separability nature of training targets. Furthermore, this LP-based method can be viewed as a neural network training algorithm since its classification procedure can be precisely replicated by an artificial neural network. The experimental results show that the proposed linear programming-based pattern classification method is promising.
Development of invariant feature maps via a computational model of simple and complex cells

In the primate's primary visual cortex (V1), cells are classified in terms of two categories: simple cells and complex cells, given their response properties. While simple cells respond strongly to gating and bar stimuli at a certain phase and location, responses of complex cells are insensitive to small translation of stimulus within the receptive field [1]. Inspired by the response properties of simple and complex cells in the primary visual cortex, we propose a computational network to learn the receptive fields of these cells, and address the development of translation invariance from a temporal sequence of natural images. A generative model with sparseness constraints is devised to minimize the energy of prediction errors. Each simple cell is modulated by a higher layer of complex cells in a multiplicative fashion, where a slowness property and a trace-like rule are enforced on complex cells, as the result of a temporal coherence soft constraint. Furthermore, non-negativity constraints of the latent cell variables and weight matrices are imposed to fit the known neurophysiology. We present an online gradient descent algorithm to train our model from natural image sequences, in which a pre-training strategy is used to initialize the weights. The developed connection weights show that complex cell outputs are directly proportional to quadratic forms of simple cell responses. Each receptive field of simple cells develop a Gabor-like orientation filter, and each complex cell pools similar simple cell receptive fields - in retinotopic and feature space - producing the locally-invariant representation.
An approach to derivative causality in bond graph models of mechanical systems

Abstract Dynamic system models involving rigidly coupled inertia elements often result in derivative causality problems when represented in bond graph form. This means that explicit state equations can only be obtained after algebraic manipulation. The problem is particularly severe when geometric nonlinearities are involved as represented by displacement modulated transformers. A practical solution is to eliminate the derivative causality by defining an I-field or an IC-field using generalized momenta and (if necessary) generalized coordinates as is done when applying Lagrange's or Hamilton's equations. The inversion of a mass matrix is required. In the worst case, the inversion may have to be done repeatedly during a computer simulation.
Construction of an Optimal Sequential Plan for Testing a Treatment for an Adverse Effect

Abstract Classical sequential procedures that collect a single observation at a time are often found impractical, expensive, and time consuming. Sequentially planned procedures, or simply sequential plans, extend and generalize the concepts of sequential analysis by allowing observations to be collected in groups of variable sizes. After every group, all of the previously collected data are used to determine the next course of action. An optimal (Bayes) sequential plan minimizes the (Bayes) risk function that combines the decision loss, observation (variable) cost, and group (fixed) cost. In general, determining the optimal sequential plan remains an open and challenging problem mainly because it requires risk optimization over a huge and rather unstructured set of all sequential plans. This article demonstrates how to obtain the optimal solution for a particular class of problems that may arise in testing a treatment for a rare but severe adverse effect. This solution is obtained by studying a number of ...
Brief Report: Associations between Emotional Competence and Adolescent Risky Behavior

The current study examines associations between emotional competence (i.e., awareness, regulation, comfort with expression) and adolescent risky behavior. Children from a longitudinal study participated at age 9 and 16 (N=88). Semi-structured interviews were conducted with children about their emotional experiences and coded for areas of emotional competence. Associations were examined for the emotions of sadness and anger concurrently during adolescence, and longitudinally from middle childhood to adolescence. Results suggested that children with poor emotional awareness and regulation had a higher likelihood of using hard drugs. Difficulty regulating emotions was associated with having more sexual partners, and both emotion regulation and expression difficulties were associated with greater behavioral adjustment problems. Results were consistent across the concurrent and longitudinal findings and pointed to anger as an important emotion. Findings suggest that children's emotional competence may serve as a useful point of intervention to decrease risky behavior in adolescence.
Elimination/minimization of edge-induced stress singularities in fiber composite laminates

Abstract The stress singularities along the edges of a linear elastic laminate consisting of 0° and off-axis plies in uniaxial stress are shown to either vanish or be minimized by a special fiber orientation for the off-axis plies. The particular orientation is obtained analytically using both a recently proposed specific three-dimensional constitutive equation and the more general constitutive theory, but for fiber-dominated lamina. The prescribed angle is defined by the simple relationship: 0 * = tan - 1 ( 1 v L ) , where v1 is the longitudinal Poisson's ratio of the lamina. Tensile test data arc consistent with the theoretical result.
Correlation between ion fluxes and ion-stimulated adenosine triphosphatase activity of plant roots.

The energy-dependent influx of Rb+ into excised roots of corn, wheat, and barley has been determined and compared to the Rb+-stimulated ATPase activity of membrane fractions obtained from root homogenates of these species. The external Rb+ concentrations studied were in the range of 1 to 50 mm. The ratio of Rb+ influx/Rb+-stimulated ATPase was approximately 0.85 and was nearly constant for all the species and Rb+ concentrations studied. The correlation coefficient for Rb+ influx versus Rb+-activated ATPase was 0.94. The results support the concept that ATP is the energy source for ion transport in roots and that an ATPase participates in the energy transduction process involved in energy-dependent ion transport.
Biological influences on modern sulfates: Textures and composition of gypsum deposits from Guerrero Negro, Baja California Sur, Mexico

Abstract Gypsum (CaSO 4 ·2H 2 O) deposits from a range of sedimentary environments at Guerrero Negro, Baja California Sur, Mexico were investigated for microscale texture and composition in order to differentiate features formed under substantial microbial influence from those for which microbial effects were relatively minor or absent. Gypsum deposits were classified according to their sedimentary environment, textures, crystal habit, brine composition and other geochemical factors. The environments studied included subaqueous sediments in anchialine pools and in solar salterns, as well as subsurface sediments of mudflats and saltpans. Gypsum that developed in the apparent absence of biofilms included crystals precipitated in the water column and subsedimentary discs that precipitated from phreatic brines. Subsedimentary gypsum developed in sabkha environments exhibited a sinuous microtexture and poikilitically enclosed detrital particles. Water column precipitates had euhedral prismatic habits and extensive penetrative twinning. Gypsum deposits influenced by biofilms included bottom nucleated crusts and gypsolites developing in anchialine pools and saltern ponds. Gypsum precipitating within benthic biofilms, and in biofilms within subaerial sediment surfaces provided compelling evidence of biological influences on crystal textures and habits. This evidence included irregular, high relief surface textures, accessory minerals (S°, Ca-carbonate, Sr/Ca-sulfate and Mg-hydroxide) and distinctive crystal habits such as equant forms and crystals having distorted prism faces.
Noninvasive prenatal chromosomal aneuploidy detection using plasma cell-free nucleic acid

It has been shown that by the end of the first trimester of pregnancy, a small but significant portion of DNA extracted from maternal plasma is of fetal origin. This knowledge has been utilized for the development of clinical diagnostic assays that are widely used outside the USA for the minimally invasive prenatal determination of, for example, fetal Rhesus antigen status. Such assays that enable the detection of paternally inherited fetal alleles are relatively straightforward, because the fetal sequence of interest is unique to the father and is therefore not masked by any identical maternal alleles. By contrast, maternally inherited traits, including the majority of common human aneuploidies such as trisomy 21, are much harder to detect in plasma because of the overwhelming background of endogenous maternal sequences that are identical to the fetal target alleles. One way to ‘see’ fetal DNA past the veil of maternal genomic DNA is to utilize methods that can selectively amplify or enrich fetal alleles...
Recent Developments in NBS Spectrographic Standard Samples of Iron-Base Alloys

Eight new ingot iron and low-alloy steel spectrographic standards, which are certified for 17 elements, including carbon and phosphorus, recently have been made available by the National Bureau of Standards. The standards are in the form of rods 7/32 in. in diameter and 4 in. long, and disks 1¼ in. in diameter and ¾ in. thick. The compositions of these standards are given in a table. Also shown in tables are the final certificate values for two groups of stainless steel spectrographic standards issued several years ago but which have had several elements added to the original certificates. Standard samples for x-ray fluorescence analysis of stainless steel (six standards) and tool steel (six standards) have been provided in the form of disks 1¼ in in diameter and ¼ in. thick.
Chemical transformations of Hg° during Arctic mercury depletion events sampled from the NASA DC-8

Abstract. Atmospheric Mercury Depletion Events (MDEs) in Arctic springtime were investigated utilizing a box model based on airborne measurements from the NASA DC-8 during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) field campaign. Measurements showed that MDEs occurred near the surface and always over the Arctic Ocean accompanied by concurrent ozone (O3) depletion, enhancement in Br2 mixing ratios, and decreases in ethyne and light weight alkanes. Backward trajectories indicated that most air masses inside the MDEs originated at low altitude over the ocean presumably generating a halogen-rich environment. We developed a box model which considered only gas phase reactions of mercury, halogen species, and O3 chemistry. We conducted a series of sensitivity simulations to determine the factors that are of most importance to MDE formation. The box model results suggested that continuous enhancement of Br2 mixing ratios, a high intensity of solar radiation, or a relatively high NOx regime expedited Hg° depletion. These environments generated high concentrations of Br radical, and thus the model results indicated that the Br radical was very important for Hg° depletion. Utilizing different rate constants for reaction of Hg° + Br produced times to reach Hg° depletion ranging from 22 to 32 h.
Computing a Bias-Optimal Policy in a Discrete-Time Markov Decision Problem

This paper treats a discrete-time Markov decision model with an infinite planning horizon and no discounting. A "bias-optimal" policy for this decision problem satisfies a criterion that is more selective than maximizing the gain rate. The problem of computing a bias-optimal policy, also treated by Veinott in 1966, is here parsed into a sequence of three simple Markov decision problems, each of which can be solved by linear programming or policy iteration.
Will escaped transgenes lead to ecological release

One potential effect of transgenes escaped from cultivation, either in crop plants themselves or introgressed into wild relatives, is release of the plants from ecological constraints that currently limit or control their distribution and abundance. Release may occur only within the community that the species presently occupies, or it may allow range expansion into new communities. Experience with ecological range expansions of invading plant species suggests that when ecological release occurs, the consequences can be severe. To assess properly the likelihood of ecological release, the factors that currently limit species' distributions and abundances must be determined by manipulative experiments. The effect of transgenes on these factors must then be investigated throughout the life cycle of the species and on a case-by-case basis. For ruderal annual species, seed survival and seedling establishment phases may be particularly important.
Rayleigh and mie enhancement of blackbody radiation in nanoscale devices

A method for suppressing long wavelength radiation in blackbody emission is presented. In particular, Rayleigh and Mie theory are considered for the design nanoscale devices to shape the spectrum of blackbody radiation. The method combines the Planck blackbody emission spectrum with the Maxwell equation based suppression of long wavelength radiation from sub-wavelength apertures. In this, constituent nanoscale devices are used as blackbody radiators rather than scatterers of an incident field, a fundamentally different notion than classical scattering of an incident electromagnetic field. In essence, the nanoscale devices serve as an intermediary for converting energy into short-wavelength photons. Although the development focuses on using nanoscale devices to enhance visible wavelength while suppressing infrared, the approach is not limited to optical wavelengths. Results are presented showing potential for reducing the emitted wavelength by 25% to 50%. Finally, the method may prove useful in applications such as energy conversion systems, solar cells, and lighting.
ON exact maximum-likelihood detection for non-coherent MIMO wireless systems: A branch-estimate-bound optimization framework

Fast fading wireless environments pose a great challenge for achieving high spectral efficiency in next generation wireless systems. Joint maximum-likelihood (ML) channel estimation and signal detection is of great theoretical and practical interest, especially for multiple-input multiple-output(MIMO) systems where the multiple channel coefficients need to be estimated. However, this is a hard combinatorial optimization problem, for which obtaining efficient exact algorithms has been elusive for the general MIMO systems. In this paper, we propose an efficient branch-estimate-bound non-coherent optimization framework which provably achieves the exact ML joint channel estimation and data detection for general MIMO systems. Numerical results indicate that the exact joint ML method can achieve substantial performance improvements over suboptimal methods including iterative channel estimation and signal detection. We also derive analytical bounds on the computational complexity of the new exact joint ML method and show that its average complexity approaches a constant times the length of the coherence time, as the SNR approaches infinity.
Two prospective studies of changes in stress generation across depressive episodes in adolescents and emerging adults.

The stress generation hypothesis was tested in two different longitudinal studies examining relations between weekly depression symptom ratings and stress levels in adolescents and emerging adults at varied risk for depression. Participants in Study 1 included 240 adolescents who differed with regard to their mother’s history of depressive disorders. Youth were assessed annually across 6 years (Grades 6 through 12). Consistent with the depression autonomy model, higher numbers of prior major depressive episodes (MDEs) were associated with weaker stress generation effects, such that higher levels of depressive symptoms predicted increases in levels of dependent stressors for adolescents with ≤ 2 prior MDEs, but depressive symptoms were not significantly related to dependent stress levels for youth with ≥ 3 prior MDEs. In Study 2, participants were 32 remitted-depressed and 36 never-depressed young adults who completed a psychosocial stress task to determine cortisol reactivity and were re-assessed for depression and stress approximately eight months later. Stress generation effects were moderated by cortisol responses to a laboratory psychosocial stressor, such that individuals with higher cortisol responses exhibited a pattern consistent with the depression autonomy model, whereas individuals with lower cortisol responses showed a pattern more consistent with the depression sensitization model. Finally, comparing across the two samples, stress generation effects were weaker for older participants and for those with more prior MDEs. The complex, multi-factorial relation between stress and depression is discussed.
Risk factors for gyrA and parC mutations in Pseudomonas aeruginosa.

OBJECTIVE The major mechanism of fluoroquinolone (FQ) resistance in Pseudomonas aeruginosa (PSA) is modification of target proteins in DNA gyrase and topoisomerase IV, most commonly the gyrA and parC subunits. The objective of this study was to determine risk factors for PSA with and without gyrA or parC mutations. DESIGN Case-case-control study SETTING Two adult academic acute-care hospitals PATIENTS Case 1 study participants had a PSA isolate on hospital day 3 or later with any gyrA or parC mutation; case 2 study participants had a PSA isolate on hospital day 3 or later without these mutations. Controls were a random sample of all inpatients with a stay of 3 days or more. METHODS Each case group was compared to the control group in separate multivariate models on the basis of demographics and inpatient antibiotic exposure, and risk factors were qualitatively compared. RESULTS Of 298 PSA isolates, 172 (57.7%) had at least 1 mutation. Exposure to vancomycin and other agents with extended Gram-positive activity was a risk factor for both cases (case 1 odds ratio [OR], 1.09; 95% confidence interval [CI], 1.04–1.13; OR, 1.14; 95% CI, 1.03–1.26; case 2 OR, 1.09; 95% CI, 1.03–1.14; OR, 1.13; 95% CI, 1.01–1.25, respectively). CONCLUSIONS Exposure to agents with extended Gram-positive activity is a risk factor for isolation of PSA overall but not for gyrA/parC mutations. FQ exposure is not associated with isolation of PSA with mutations. Infect Control Hosp Epidemiol 2015;00(0): 1–7
Ligand-Gated Ion Channels

This Teaching Resource provides a summary and slides derived from a lecture covering ligand-gated ion channels (LGICs), and is part of the course "Cell Signaling Systems: A Course for Graduate Students." The lecture focuses on two families of LGICs: the Cys-loop receptors and the ionotropic glutamate receptors. For Cys-loop receptors, much of the material is based on studies of the nicotinic acetylcholine receptor, including overall receptor topology, the basis for ionic selectivity, the identity of the gate, and the coupling of agonist binding to the opening of the gate. In the glutamate receptors, the conserved topology, and the differential kinetics and ion selectivities, among the AMPA-type and NMDA-type glutamate receptors are covered. The unique voltage-dependence of NMDA-type receptors is addressed, with special reference to the role of these receptors in synaptic plasticity.