cssi/SciSciGPT-SciSciNet huggingface dataset:
La1−x−0.025Ce0.025Sr2+xAl1−xSixO5 solid solutions as tunable yellow phosphors for solid state white lighting

Solid solutions of two isotypic compounds from the end members LaSr2AlO5 and Sr3SiO5 are hosts for Ce3+ activator ions, allowing for careful tuning of the various parameters associated with efficient solid state (blue + yellow =) white lighting. By incorporating this phosphor with an encapsulant on InGaN light-emitting diodes (λmax = 430 nm), we obtain white light with a color rendering index (Ra) between 67 and 70 and color temperatures between 6550 and 7345 K, with relatively high efficacies, suggesting these solid solutions are promising for applications in solid state white lighting.
Common and distinct associations between aggression and alcohol problems with trait disinhibition

Disinhibition (vs. Constraint; DvC) represents the tendency to act in an undercontrolled (vs. controlled) manner and has been shown to be strongly linked to externalizing psychopathology. Further, recent research has found lower-order DvC components to have distinct patterns of associations with important externalizing-related outcomes, suggesting that although DvC represents a general diathesis to externalizing behaviors, lower order components likely present more specific risks for particular behaviors. To further characterize the association between components of DvC and externalizing behaviors, the current study aimed to expand upon these recent findings by examining common and distinct associations between components of DvC and aggression and alcohol problems within a large, diverse sample of undergraduates (N = 933; 36.8 % Black/African-American, 34.3 % White, 14.6 % Asian/Asian-American). Results of structural equation modeling analyses revealed that low Agreeableness and low Self-Control/Premeditation evidenced distinct patterns of associations with externalizing outcomes. Although low Agreeableness and low Self-Control/Premeditation were both associated with all externalizing outcomes, low Agreeableness was most strongly associated with Proactive Aggression whereas low Self-Control/Premeditation was most strongly associated with Reactive Aggression and alcohol problems. These associations did not vary by either race (White vs. African-American) or gender. Further, the three DvC components significantly interacted with one another in explaining these externalizing outcomes. Taken together, these findings suggest both common and distinct associations between DvC and externalizing behaviors that are generalizable to both White and African-American, as well as both male and female, participants. The current study therefore confirms the importance of focusing on lower-order DvC components in future research in service of further explicating differential DvC-related etiological mechanisms associated with various phenotypic expressions of the externalizing spectrum of behavior.
Nanoparticle dynamics: a multiscale analysis of the Liouville equation.

A theory of nanoparticle dynamics based on scaling arguments and the Liouville equation is presented. We start with a delineation of the scales characterizing the behavior of the nanoparticle/host fluid system. Asymptotic expansions, multiple time and space scale techniques, the resulting coarse-grained dynamics of the probability densities of the Fokker−Planck−Chandrasekhar (FPC) type for the nanoparticle(s), and the hydrodynamic models of the host medium are obtained. Collections of nanoparticles are considered so that problems such as viral self-assembly and the transition from a particle suspension to a solid porous matrix can be addressed via a deductive approach that starts with the Liouville equation and a calibrated atomic force field, and yields a generalized FPC equation. Extensions allowing for the investigation of the rotation and deformation of the nanoparticles are considered in the context of the space-warping formalism. Thermodynamic forces and dissipative effects are accounted for. The no...
Technical efficiency of carp pond culture in South Asia: An application of a stochastic meta‐production frontier model

Abstract A stochastic meta‐production frontier model is estimated to examine the inter‐country differences in levels of technical efficiency of semi‐intensive/intensive and extensive carp pond culture systems among the major carp producing countries in South Asia, namely India, Bangladesh, Pakistan, and Nepal. The mean technical efficiencies for semi‐intensive/intensive farms vary from 0.68 for Nepal to 0.79 for India, with an overall average of 0.75 and those for extensive farms vary from 0.48 for Bangladesh to 0.62 for Pakistan, with an overall mean of 0.57. Differences in efficiency levels are explained in terms of various farm‐specific and country‐specific factors by estimating a model for technical inefficiency effects. The adoption of recommended fish, water, and feed management practices is found to be critical for improved performance of carp producers. For each country, the study also compares the efficiency scores based on its own production frontier with those obtained from the meta‐production ...
On fundamental theorems of algebraic K-theory

and Staffeldt [6] have given simplified proofs of some of the foundational theorems of algebraic K-theory [S]. Especially in Staffeldt’s treatment these theorems are shown to be consequences, via standard homotopy theoretical methods, of the so-called additioity theorem which therefore assumes the role of a basic result in algebraic K-theory. There are two formulations of the additivity theorem, one in terms of original Q-
Isolation of a Substance with Blood ‐group P1 Activity from Human Erythrocyte Stroma

Lyophilized erythrocyte stroma were extracted with chloroform methanol, and a fraction with blood-group P1 activity was obtained by chromatography on columns of silicic acid followed by preparative thin-layer chromatography. The active fraction contained at least two glycosphingolipids, and it is concluded, tentatively, that the erythrocyte P1 antigen is a glycosphingolipid.
2013 William Allan Award Introduction: Aravinda Chakravarti1

The highest and most prestigious honor that The American Society of Human Genetics (ASHG) can bestow on any scientist is the William Allan Award. This honor is awarded each year in memory of William Allan to a scientist who has had far-reaching and substantial scientific contributions to the field of human genetics and who has thus demonstrated a sustained period of productivity over their lifetime. William Allan was a physician, an educator, and one of the early pioneers of American human genetics.
Treatment, promotion, commotion: antibiotic alternatives in food-producing animals

Alternatives to antibiotics are urgently needed in animal agriculture. The form these alternatives should take presents a complex problem due to the various uses of antibiotics in animal agriculture, including disease treatment, disease prevention, and growth promotion, and to the relative contribution of these uses to the antibiotic resistance problem. Numerous antibiotic alternatives, such as pre- and probiotics, have been proposed but show variable success. This is because a fundamental understanding of how antibiotics improve feed efficiency is lacking, and because an individual alternative is unlikely to embody all of the performance-enhancing functions of antibiotics. High-throughput technologies need to be applied to better understand the problem, and informed combinations of alternatives, including vaccines, need to be considered.
A MICRORADIOGRAPHIC-MICROPHOTOMETRIC AND POLARIZED-LIGHT STUDY OF THE DEMINERALIZATION PATTERN IN CARIOUS LESIONS.

Abstract The pattern of demineralization in incipient and advanced carious lesions in the enamel of deciduous and permanent teeth was studied in hand-lapped planoparallel ground sections by microradiographic-microphotometric and polarized-light procedures. Polarized-light and microradiographic examination revealed that incipient carious lesions had a higher mineral content at the outer surface as compared to underlying enamel, the latter having varying degrees of demineralization in different areas. There was no indication of hypercalcified areas. The progress of the lesion along the striae of Retzius and the interprismatic substance was disclosed. From without inward, the main body of the lesion, the dark zone, and the translucent zone could be identified. In some cases there appeared to be an additional translucent zone within the central part of the lesion. Comparison of densitometric tracings of microradiographs and intrinsic retardation measurements showed greatest demineralization in the dark zone and minimal demineralization in the translucent zone. A similarity was found between carious lesions in deciduous and permanent teeth.
Juvenile firesetting: A review and methodological critique☆

Abstract Juvenile firesetting is a potentially dangerous behavior that contributes significantly to the national fire problem and has medical, financial, social, and psychological implications. As one form of preventable emergency, firesetting behavior has generated a burgeoning psychological and psychiatric literature and a demand by fire service organizations for increasing professional involvement. This paper reviews the existing clinical and research literature and attempts to provide a substantive overview of the descriptive characteristics, assessment, and treatment of the juvenile firesetter. Areas in need of further exploration are highlighted in the context of a discussion of theoretical, methodological, therapeutic, and organizational issues.
State-space control of prosthetic hand shape

In the field of neuroprosthetic control, there is an emerging need for simplified control of high-dimensional devices. Advances in robotic technology have led to the development of prosthetic arms that now approach the look and number of degrees of freedom (DoF) of a natural arm. These arms, and especially hands, now have more controllable DoFs than the number of control DoFs available in many applications. In natural movements, high correlations exist between multiple joints, such as finger flexions. Therefore, discrepancy between the number of control and effector DoFs can be overcome by a control scheme that maps low-DoF control space to high-DoF joint space. Imperfect effectors, sensor noise and interactions with external objects require the use of feedback controllers. The incorporation of feedback in a system where the command is in a different space, however, is challenging, requiring a potentially difficult inverse high-DoF to low-DoF transformation. Here we present a solution to this problem based on the Extended Kalman Filter.
"Nonspecific" ST and T-Wave Changes

A study was made of 1,000 consecutive adult in-patient electrocardiograms to determine the possibility of making a more precise diagnosis than "nonspecific ST and T-wave changes." More than 50 per cent (209) of the 410 abnormal electrocardiograms (exclusive of arrhythmias) were characterized by nonspecific depression of ST segment or T wave inversion, or both. These 209 cases comprised four groups: (1) 46 patients (22 per cent) had received digitalis, which could account for the ST-T changes; (2) 57 patients (27 per cent) had had an acute episode of cardiac pain within 5 days prior to the electrocardiogram; (3) 57 patients (27 per cent) had had no recent cardiac pain but suffered from some disease that could be regarded as a possible cause for the ST-T changes; and (4) 49 patients (24 per cent) had no apparent cause for the electrocardiographic changes. In the last group, in contrast with the others, the ST-segment depression was less than 0.5 mm. and the T-wave inversion less than 1 mm. In patients with ...
Electrophoretic analysis of amylase isozymes in geographical strains of Sitophilus oryzae (L.), S. zeamais Motsch., and S. granarius (L.) (Coleoptera: Curculionidae)

Abstract Electrophoretic analysis of adult intestinal tracts indicated that two strains of Sitophilus oryzae (L.) (Japan and Tanzania-90) lacked the major α-amylase isozyme present in 12 other geographical strains. Amylase zymograms of adults of 17 strains of Sitophilus zeamais Motschulsky were not only different from those of S. oryzae but showed significant between-strain variation. Strains of S. zeamais could be arranged into approximately four groups based on isoamylase patterns. There was no apparent correlation between geographical origin or culture diet and isoamylase pattern within these groups. One strain of Sitophilus granarius (L.) (3SG) had an additional minor isozyme not present in five other strains of this species. Although the biological or functional significance of the wide strain to strain variation in isoamylase patterns of S. zeamais has yet to be determined, the qualitative and quantitative differences in amylases between these weevil species indicate these enzymes may be useful chemotaxonomic markers. In addition to differences in amylase composition, there was significant strain variation in weights of wheat-fed weevils from each species.
An example in “significant-digit” arithmetic

Different methods of handling the summing process for the geometric series are shown to give results indicating widely differing significances when carried out in a machine incorporating “significant-digit” arithmetic.
Developmental aspects of the effects of spinal cord transection upon audiogenic seizures in mice

The contributions of somatic sensory and motor processes during audiogenic seizures were investigated in mice. Subjects were 395 DBA/2J mice which received either complete transection of the lower thoracic spinal cord or an identical sham operation without actual cordotomy. Additional control procedures were also employed to detect “side effects” of surgery. Paraplegic mice, lacking substantial input from the posterior body, were compared with control mice for seizures. Postoperative intervals of 1 h, 1 day, 4–5 days, or 12 days were used in mice of various ages. Convulsions cephalad to paralysis were studied in two experiments. In 21 day-old-mice (at the ontogenic peak of susceptibility to audiogenic seizures), paraplegic subjects had substantially reduced incidences of wild-running attacks, clonic-tonic convulsions, and fatalities induced by a 95-dB SPL noise band (Experiment 1). In contrast to 21-day-olds, younger and older paraplegic mice did not differ from their respective control mice in seizure incidence. In fact, there was a tendency for paraplegic mice to be more susceptible to audiogenic seizures at these ages (Experiment 2). The findings indicate that interruption of spinal cord pathways influenced paroxysmal activity in the brain, and this influence was related to ontogenic factors.
Design of self-compensated, water-hydrostatic bearings

Abstract A new type of hydrostatic bearing for precision machine linear motion axes has been developed and tested. The bearing has many of the traditional benefits of hydrostatic bearings systems including high stiffness (on the order of 2,000 N/μm at a supply pressure of 13.5 atm), excellent straightness characteristics (less than 0.5 μm vertical motion over 100 mm), which can exceed the straightness characteristics of the rails by using the averaging effect of the fluid, high damping, and low noise levels. Additionally, the bearings are modular in design, and use water-based cutting fluids (or pure water) as the hydrostatic fluid so it does not have the environmental problems associated with oil-based hydrostatic systems. The smallest passage is typically 3–5 mm in diameter, which virtually eliminates clogging of the hydrostatic passages. The design of the bearing system is simplified primarily by the deterministic design of the restrictor passages. The restrictors have a linear sensitivity with respect to stiffness. Fixed-compensation restrictors have a gap cubed sensitivity. This also helps manufacturing significantly because hand-tuning of restrictors is eliminated, and the restrictors are less sensitive to manufacturing errors than are traditional hydrostatic bearing systems.
Replica Exchange Simulations of the Thermodynamics of Aβ Fibril Growth

Replica exchange molecular dynamics and an all-atom implicit solvent model are used to probe the thermodynamics of deposition of Alzheimer's Aβ monomers on preformed amyloid fibrils. Consistent with the experiments, two deposition stages have been identified. The docking stage occurs over a wide temperature range, starting with the formation of the first peptide-fibril interactions at 500 K. Docking is completed when a peptide fully adsorbs on the fibril edge at the temperature of 380 K. The docking transition appears to be continuous, and occurs without free energy barriers or intermediates. During docking, incoming Aβ monomer adopts a disordered structure on the fibril edge. The locking stage occurs at the temperature of ≈360 K and is characterized by the rugged free energy landscape. Locking takes place when incoming Aβ peptide forms a parallel β-sheet structure on the fibril edge. Because the β-sheets formed by locked Aβ peptides are typically off-registry, the structure of the locked phase differs from the structure of the fibril interior. The study also reports that binding affinities of two distinct fibril edges with respect to incoming Aβ peptides are different. The peptides bound to the concave edge have significantly lower free energy compared to those bound on the convex edge. Comparison with the available experimental data is discussed.
Inverse problems in radiative transfer: Layered media

Abstract A basic problem in radiative transfer is the estimation of the physical parameters of a scattering and absorbing atmosphere based on measurements of the diffusely reflected light. In this series of papers we shall show how such tasks may be viewed as nonlinear boundary-value problems which may be solved computationally using the technique of quasilinearization. In this paper we consider a stratified atmosphere consisting of two layers illuminated by a source of uniform parallel rays. Our aim is to determine the optical depth and the albedo for single scattering of each layer based on measurements of the angular dependence of the light diffusely reflected from the slab. The results of some numerical experiments are presented.
A mobile program for enhancing engineering education

This paper focuses on a mobile K-12 outreach program titled "Engineers on Wheels" (EOW). Funding was acquired to retrofit two vans with modern technology and engineering activities. Travel is conducted in colorful vehicles that represent the institution name and bring engineering alive for the select audience. The idea for a mobile program was developed as many school districts do not have resources for field trips. These vans are driven to area schools to promote all engineering disciplines to K-12 students and educators. Engineering activities are also demonstrated outside the vehicles at scheduled school locations. The goal of the EW project is to deliver engineering concepts into K-12 classrooms using simple cost effective hands on activities. This project is unique in that the activities are developed or selected entirely by engineering students and delivered to school districts by students/faculty. Engineering students develop and pilot the activities, lesson plans, and handouts, for the Engineers on Wheels project through a course called the Engineering Clinic. All engineering disciplines are represented via these activities to give students a well-rounded idea of what different engineering involves. Samples of activities include Solar, Wind and Water Power, Biodiesel and Lip Gloss Processing, Bridge Building, Strength of Materials etc. The goal of the project is to use these activities to mitigate some of the issues that prevent girls and boys from understanding engineering and its specialty areas, thus preventing consideration of engineering as a career choice. Students travel to select school districts throughout the academic year to expose the challenges and excitement of engineering to K-12 students and educators. Surveys are conducted to assess the impact of the program. This successful program is in its seventh year and just received national recognition as the 2013 WEPAN Outstanding Women in Engineering Program Initiative.
Structural variation in organically templated uranium sulfate fluorides

The ability of templated uranium sulfate fluorides to adopt diverse inorganic architectures is demonstrated in six novel materials. The inorganic structures present in [N2C6H16][UO2F2(SO4)](USFO-2), [N2C6H16][UO2F(SO4)]2(USFO-3), [N2C3H12][UO2F(SO4)]2.H2O (USFO-4), [N2C5H14][UO2F(H2O)(SO4]2(USFO-5), [N2C6H18]2[UO2F(SO4)]4.H2O (USFO-6) and [N2C3H12][UO2F(SO4)]2.H2O (USFO-7) range from infinite chains to five different layer topologies. The chain, and two of the five layers, have unprecedented structure types. These compounds illustrate the structural diversity within this new family of materials, arising from the varied coordination of the U6+ centres. Each material was synthesised under hydrothermal conditions, through reaction of uranyl acetate, sulfuric acid, HF(aq), water, and the respective organic template.
Petrofacies and provenance of a Late Cretaceous suture zone thrust-top basin, Cantwell Basin, central Alaska Range

ABSTRACT The lower Cantwell Formation, in the Cantwell basin, provides an excellent opportunity to study the petrofacies and provenance of siliciclastic deposits from an ancient thrust-top basin. The Late Cretaceous Cantwell basin formed on a series of thrust sheets along a suture zone between the allochthonous Wrangellia composite terrane and the North American continental margin (i.e., the Yukon-Tanana terrane). Analysis of the lower Cantwell Formation provides an understanding of sediment transport in the interior of an ancient suture zone. Sandstone and conglomerate compositional data indicate two main source areas for the lower Cantwell Formation: (1) uplifted thrust sheets, located south of the basin, associated with development of the suture zone, and (2) a regional anticlinorium, locat d north of the basin, along the North American continental margin. In the northwestern Cantwell basin, petrofacies, southward paleocurrent directions, and alluvial lithofacies record reactivation of a regional anticlinorium located in the metamorphic Yukon-Tanana terrane. Lithic types in this part of the basin are dominated by quartz-mica tectonite, mica schist, metamorphic chert, and other quartz-rich metamorphic and sedimentary varieties (Q48F2L50; Lv0Lm54Ls46). In the northeastern and southern parts of the basin, sediment was derived from volcanic and sedimentary strata exposed in the hanging walls of thrust faults that define the southern margin of the basin. Source-diagnostic conglomerate clasts, spatial variations in sandstone detrital modes, northward paleocurrent indicators, and progressively rotated strata record syndepositional uplift of local thrust sheets along the suture zone. The dominant sandstone grain types in these parts of the basin are plagioclase grains and lithic fragments of argillite, radiolarian-bearing mudstone, and metabasalt (Q44F28L28; Lv2Lm23Ls75). Sandstone compositions documented for the Cantwell basin may be typical of thrust-top basins that form along suture zones. The two main petrofacies of the lower Cantwell Formation consist of a petrofacies rich in sedimentary and volcanic detritus associated with uplifted oceanic rocks along areas of the basin proximal to the suture zone, and a petrofacies characterized by quartz-rich metamorphic and sedimentary detritus along areas of the basin proximal to the deformed continental margin. Compositional data from this study, combined with previous petrologic studies of similar basins, show that sandstones from suture zone thrust-top basins are more feldspathic than sandstones from "typical" foreland basins. These compositional differences reflect a complex assemblage of accreted terran s, which include relict volcanic arcs, batholiths, oceanic sedimentary deposits, and ophiolitic melanges, that are accreted to continental margins along suture zones in collisional-accretionary orogenic belts.
Foraging to balance conflicting demands: novel insights from grasshoppers under predation risk

Animal foraging may be influenced by multiple demands simultaneously (eg., nutrient gain and predator avoidance). Conventional approaches to understand the trade-ofii between these demands require cramming them in ffmilar currencies, which is impractical in many field situations. We introduce a new method, called multiobjective programming, as a framework to explore how animals balance conflicting demands. Multiobjective programming allows one to explore die influence of foraging demands directly, without explicit assumptions about how they enter into fitness and without conversion to some common currency. Using multiobjective programming, we show that, as foraging demands change, animait may adaptivety adjust their behavior, even if the constraints on feasible behavior are unaffected (contrary to die predictions of the conventional models). Hence, we may see a variable response in foraging that is consistent with adaptive behavior. We used an empirical test with herbivore grasshoppers and predator spiders to evaluate die utility of multiobjective programming Our experiments show that grasshoppers are able to optimally balance die foraging objectives of energy intake and vigilance under changing levels of predation risk. The multiobjective model is used both to evaluate die biological «ignifiranrf of the broad variation that was observed in die grasshoppers' foraging behavior and to quantify explicitly die trade-off between energy intake and predator avoidance. Key words: adaptive behavior, Mdanopius ftmui i ubrwn, multiobjective optimization, optimal foraging, single-objective optimization, tradeoffs, variability. fBthav Ecol 8:551-559 (1997)]
Numerical and Experimental Analysis of the Static and Dynamic Morphing Characteristics of a Chiral Core Airfoil

Aeroelastic tailoring requires structural compliance and thus often conflicts with stiffness requirements to carry prescribed aerodynamic loads. Recently however, the application of cellular structural concepts has suggested the potential to achieve compliance while conserving required load-carrying capacity. Among the proposed concepts, a chiral geometry in particular is a novel configuration which features an in-plane negative Poisson’s ratio which leads to a very high shear modulus, while maintaining some degree of compliance. In particular, the chiral geometry allows large continuous deformations of the airfoil assembly, with the constitutive material remaining in the linear region of its stress-strain curve. The ability to sustain large deformations without exceeding yield conditions is required to recover the original shape and to provide smooth deformations as required by aerodynamic considerations. In previous work, a coupled-physics model, comprising of simultaneous CFD and elastic analyses, is developed to investigate the influence of the chiral core geometry on the behavior of a given airfoil. The modification of geometric parameters defining the considered layout leads to significant variations in mechanical properties, which can be exploited to achieve various levels of compliance. The morphing capabilities of the proposed airfoil, quantified as camber changes, are evaluated for various design configurations of the internal core structure. Specifically, three such airfoils have been constructed to study the influence of core geometric parameters on the elastic behavior observed in numerical simulations. Experiments on the aforementioned airfoil samples are characterized by imposing large camber-wise deflections, via static loading, and measuring the resulting strain, both in the honeycomb core and in the airfoil profile. The experimental results confirm the ability of the airfoils to sustain large deflections while not exceeding yield strain limits, in addition to producing continuous deformations, which are critical for the implementation of aeroelastic tailoring.
Ethanol exposure decreases mitochondrial outer membrane permeability in cultured rat hepatocytes

Mitochondrial metabolism depends on movement of hydrophilic metabolites through the mitochondrial outer membrane via the voltage-dependent anion channel (VDAC). Here we assessed VDAC permeability of intracellular mitochondria in cultured hepatocytes after plasma membrane permeabilization with 8 microM digitonin. Blockade of VDAC with Koenig's polyanion inhibited uncoupled and ADP-stimulated respiration of permeabilized hepatocytes by 33% and 41%, respectively. Tenfold greater digitonin (80 microM) relieved KPA-induced inhibition and also released cytochrome c, signifying mitochondrial outer membrane permeabilization. Acute ethanol exposure also decreased respiration and accessibility of mitochondrial adenylate kinase (AK) of permeabilized hepatocytes membranes by 40% and 32%, respectively. This inhibition was reversed by high digitonin. Outer membrane permeability was independently assessed by confocal microscopy from entrapment of 3 kDa tetramethylrhodamine-conjugated dextran (RhoDex) in mitochondria of mechanically permeabilized hepatocytes. Ethanol decreased RhoDex entrapment in mitochondria by 35% of that observed in control cells. Overall, these results demonstrate that acute ethanol exposure decreases mitochondrial outer membrane permeability most likely by inhibition of VDAC.
Leadership and Change at NASA: Sean O’Keefe as Administrator

Sean O’Keefe was administrator of NASA a little more than three years. In that eventful and turbulent period, he dealt with numerous issues. Appointed to cope with a huge cost overrun on the International Space Station, he was soon engulfed in the Columbia shuttle accident and its investigation. Subsequently, he engineered a presidential decision that NASA return to the moon and go eventually to Mars. He also sought to terminate the immensely popular Hubble Space Telescope. The Moon-Mars decision was O’Keefe’s most important achievement, as that involving Hubble was his most controversial action. This essay tracks O’Keefe’s role at NASA as a case study in leadership and change.
Envy-Free Pricing with General Supply Constraints for Unit Demand Consumers

The envy-free pricing problem can be stated as finding a pricing and allocation scheme in which each consumer is allocated a set of items that maximize his/her utility under the pricing. The goal is to maximize seller revenue. We study the problem with general supply constraints which are given as an independence system defined over the items. The constraints, for example, can be a number of linear constraints or matroids. This captures the situation where items do not pre-exist, but are produced in reflection of consumer valuation of the items under the limit of resources. This paper focuses on the case of unit-demand consumers. In the setting, there are n consumers and m items; each item may be produced in multiple copies. Each consumer i ∈ [n] has a valuation vij on item j in the set Si in which he/she is interested. He/she must be allocated (if any) an item which gives the maximum (non-negative) utility. Suppose we are given an α-approximation oracle for finding the maximum weight independent set for the given independence system (or a slightly stronger oracle); for a large number of natural and interesting supply constraints, constant approximation algorithms are available. We obtain the following results. 1) O(α log n)-approximation for the general case. 2) O(αk)-approximation when each consumer is interested in at most k distinct types of items. 3) O(αf)-approximation when each type of item is interesting to at most f consumers. Note that the final two results were previously unknown even without the independence system constraint.
Factors Limiting Reproductive Efficiency in Selected Laboratory Animals

The mouse, rat, hamster, and rabbit have had remarkable success in surviving in the wild, which attests to their high reproductive capability. In fact, Parkes refers to mice conceiving at each postpartum estrus having the potential for 13 litters per year. Paufler et al. used GnRH to repeatedly cause ovulation in 27 rabbits a few days after parturition, resulting in an average pregnancy rate of 71.5%, 7.0 young born, 5.8 young weaned, and 50 young per doe per year. All four species produce an excess of spermatozoa relative to the requirements for fertilization. The rabbit is suitable for semen collection, artificial insemination, and most of the techniques one might wish to model for reproductive studies in both males and females. A major limitation to reproduction in these species is that reproductive capacity fails long before the finite oocyte population formed prenatally is depleted. The uterus of the aged female appears to be the major cause of reproductive failure, as fertilized eggs replaced in such a uterus usually soon deteriorate. With in vitro techniques, much is still to be learned about harvesting, maturing and fertilizing oocytes and identifying those most likely to result in formation of a healthy neonate.
Gas release rates from pyroclastic flows: a assessment of the role of fluidisation in their emplacement

Estimates are presented for the rates of release of dissolved water from the particles in a pyroclastic flow by diffusion. Velocities of gas escaping from pyroclastic flows of different thicknesses are calculated. For quite small residual gas contents (0.2 to 0.8% H2O), gas velocities of 10 to over 100 cm/sec during the first 103 sec of release are estimated for flows of thickness 1 to 20 m, which experimental studies demonstrate are the velocities required to fluidise fine to medium ash. Flows with high residual gas contents or large volume (thick flows) are likely to be substantially fluidised by exsolving gas. 30% to over 60% of the particles in such flows are predicted to be fluidised. Fluidisation is thus believed to be an important mechanism in the flow and in determining the mobility of the large magnitude, prehistoric pyroclastic flows which formed extensive ignimbrite sheets. Small pyroclastic flows, however, of the magnitude observed in several historic eruptions are not believed to be fluidised, because of their low residual gas contents, small volume, and the substantial amount of cooling that occurs during their emplacement.
Augmentation of 1-β-d-Arabinofuranosylcytosine Cytotoxicity in Human Tumor Cells by Inhibiting Drug Efflux

Dipyridamole is a potent inhibitor of membrane nucleoside transport into mammalian cells. Since the membrane transporter mediates both the influx and the efflux of nucleosides, dipyridamole should be able to block nucleoside efflux from cells as well. In human ovarian carcinoma cells (2008) and promyelocytic leukemia cells (HL60), we observed that sequential treatment with 20 µm dipyridamole 2 h after their initial exposure to varying concentrations of 1-β-d-arabinofuranosylcytosine (ara-C) increased the cytotoxicity of this nucleoside analogue by 100 to 300% at all drug concentrations tested. In washout experiments in which cells were exposed to radiolabeled ara-C for 2 h and reincubated in fresh medium, the presence of 20 µm dipyridamole in the reincubation medium resulted in significantly elevated levels of intracellular radioactivity at the end of a 24-h period. High performance liquid chromatography analyses of cellular nucleotide pools during this 24-h period revealed that cells treated with the sequential ara-C/dipyridamole regimen have 2- to 3-fold higher levels of ara-CTP at all time points studied. Using alkaline elution assays, we measured a 30% increase in DNA strand breaks in cells treated with ara-C followed by dipyridamole when compared to cells treated with ara-C alone, while dipyridamole alone did not produce DNA lesions. ara-C resistance in tumor cells is associated with either the natural substrates competing with ara-C for phosphorylation and incorporation into macromolecules or increased catabolism of the parent drug. Sequential exposure regimens may overcome such tumor resistance by increasing the cellular pools of ara-C and its metabolites. A second advantage to the sequential regimen is that the prolonged retention of ara-C in non-S-phase cells may improve its efficacy. The applicability of such regimens in treating human cancer awaits the results from preclinical efficacy and toxicity trials.
Personal Leadership Conundrum

The Personal Leadership Conundrum leadership development project is a semester-long, personal leadership inquiry that provides students with a self-directed learning opportunity. The guiding framework for this leadership inquiry is a personal leadership conundrum developed by students based on their experience. Students engage in problem-based learning and reflect on their experience to develop a clear understanding of their conundrum and how they might resolve it in practice. The exercise provides a structure through which students can become lifelong learners. In addition to the students' personal development, through interviews conducted by the students with leaders, the project creates a community of inquiry into leadership within the institution and/or field that it is employed.
Proximal tubular injury and rapid formation of atubular glomeruli in mice with unilateral ureteral obstruction: a new look at an old model

Unilateral ureteral obstruction (UUO), employed extensively as a model of progressive renal interstitial fibrosis, results in rapid parenchymal deterioration. Atubular glomeruli are formed in many renal disorders, but their identification has been limited by labor-intensive available techniques. The formation of atubular glomeruli was therefore investigated in adult male mice subjected to complete UUO under general anesthesia. In this species, the urinary pole of Bowman's capsule is normally lined by tall parietal epithelial cells similar to those of the proximal tubule, and both avidly bind Lotus tetragonolobus lectin. Following UUO, these cells became flattened, lost their affinity for Lotus lectin, and no longer generated superoxide (revealed by nitroblue tetrazolium infusion). Based on Lotus lectin staining, stereological measurements, and serial section analysis, over 80% of glomeruli underwent marked transformation after 14 days of UUO. The glomerulotubular junction became stenotic and atrophic due to cell death by apoptosis and autophagy, with concomitant remodeling of Bowman's capsule to form atubular glomeruli. In this degenerative process, transformed epithelial cells sealing the urinary pole expressed α-smooth muscle actin, vimentin, and nestin. Although atubular glomeruli remained perfused, renin immunostaining was markedly increased along afferent arterioles, and associated maculae densae disappeared. Numerous progressive kidney disorders, including diabetic nephropathy, are characterized by the formation of atubular glomeruli. The rapidity with which glomerulotubular junctions degenerate, coupled with Lotus lectin as a marker of glomerular integrity, points to new investigative uses for the model of murine UUO focusing on mechanisms of epithelial cell injury and remodeling in addition to fibrogenesis.
The Role of Daily Positive Emotions During Conjugal Bereavement

The role of daily positive emotions in the stress process was examined in a sample of 34 recently bereaved older adult widows. Humor coping and perceived stress were measured in questionnaires, and positive emotions, depression, anxiety, and stress were assessed daily for 98 days. Results highlight the critical role of daily positive emotions in the months immediately following conjugal loss. Intraindividual analyses revealed significant reductions in the magnitude of the stress-depression correlation on days in which greater positive emotions were present. Results also suggest that different vulnerability and resilience factors are implicated in the emotion differentiation process. For widows with greater humor coping skills, there was less overlap in daily ratings of positive emotions and depressive symptoms. In contrast, higher levels of chronic stress resulted in less differentiation of emotional responses.
Management and therapy for cardiomyopathy in Friedreich's ataxia.

The autosomal-recessive disorder Friedreich’s ataxia is characterized by progressive ataxia, often in association with cardiomyopathy. The most frequent cause of death is cardiac dysfunction, reflecting congestive heart failure, ventricular arrhythmias and cardio–embolic stroke. With the discovery of the underlying genetic mutation, a variety of novel therapies are now progressing into clinical trials. Consequently, it is crucial to understand the features of cardiomyopathy in this disease and how new treatments may improve cardiac function. The present artcle reviews the molecular basis of the disease, the clinical features of cardiomyopathy in Friedreich’s ataxia and the upcoming therapies.
The Popular Front in France: Prelude or Interlude?.

â€œFrenchman, too conservative to go communist, too anarchistic to like fascism, what are you going to do with yourself?â€ Thus was concluded a penetrating diagnosis of contemporary social trends in France published about a year ago. It is significant that such a survey should have come from the pen of a brilliant young journalist belonging to what may be called the post-war generation. For, whatever else recent dramatic developments in French public affairs may portend, there is no doubt that political control is passing to a new set of leaders, as well as, perhaps, to new ideologies.France is now twenty-two years removed from the outbreak of the World War. Men born as late as 1900 are approaching middle age. Among the eighth of the population now over sixty years of age, only a handful of persons remain who can remember the Franco-Prussian War. Most of the men who were directing national policy through the World War and the peace settlement have diedâ€”Clemenceau, PoincarA©, Briand, PainlevA©, Barthou, Viviani, and Ribot.
Detection of Macrolide Resistance in Mycoplasma pneumoniae by Real-Time PCR and High-Resolution Melt Analysis

Mycoplasma pneumoniae is a significant cause of community-acquired pneumonia, which is often empirically treated with macrolides or azalides such as erythromycin or azithromycin. Recent studies have discovered the existence of macrolide-resistant strains within the population that have been mapped to mutations within the domain V region of the 23S rRNA gene. Currently, identification of these resistant strains relies on time-consuming and labor-intensive procedures such as restriction fragment length polymorphism, MIC studies, and sequence analysis. The current study reports two distinct real-time PCR assays that can detect the A2063G or A2064G base mutation (A2058G or A2059G by Escherichia coli numbering) conferring macrolide resistance. By subjecting the amplicon of the targeted domain V region of the 23S rRNA gene to a high-resolution melt curve analysis, macrolide-resistant strains can quickly be separated from susceptible strains. Utilizing this method, we screened 100 clinical isolates and found 5 strains to possess mutations conferring resistance. These findings were concordant with both sequencing and MIC data. This procedure was also used successfully to identify both susceptible and resistant genotypes in 23 patient specimens. These patient specimens tested positive for the presence of M. pneumoniae by a separate real-time PCR assay, although the bacteria could not be isolated by culture. This is the first report of a real-time PCR assay capable of detecting the dominant mutations that confer macrolide resistance on M. pneumoniae, and these assays may have utility in detecting resistant strains of other infectious agents. These assays may also allow for clinicians to select appropriate treatment options more rapidly and may provide a convenient method to conduct surveillance for genetic mutations conferring antibiotic resistance.
Terascale Beam-Beam Simulations for Tevatron, RHIC and LHC

In this paper, we report on recent advances in terascale simulations of the beam-beam interaction in Tevatron, RHIC and LHC. Computational methods for self-consistent calculation of beam-beam forces are reviewed. A new method for solving the two-dimensional Poisson equation with open boundary conditions is proposed and tested. This new spectral-finite difference method is a factor of four faster than the widely used FFT based Green function method for beam-beam interaction on axis. We also present applications to the study of antiproton losses during the injection stage at Tevatron, to the study of multiple bunch coherent beam-beam modes at RHIC, and to the study of beam-beam driven emittance growth at LHC.
Very high strain-rate response of a NiTi shape-memory alloy

The compressive response of a NiTi shape-memory alloy is investigated at high strain rates, using UCSDs modified split Hopkinson pressure bar and a mini-Hopkinson bar with specially designed striker bars. To obtain a constant strain rate during the formation of the stress-induced martensite phase in a Hopkinson test, a copper-tube pulse shaper of suitable dimensions or a stepped striker bar is employed, since without a pulse shaper or with a uniform striker bar, the strain rate of the sample will vary significantly as the materials microstructure changes from austenite to martensite, whereas with proper pulse shaping techniques a nearly constant strain rate can be achieved over a certain deformation range. At a very high strain rate, the yield stress and the stress-induced martensite formation process are significantly different from those at moderately high strain rates, suggesting that, correspondingly, different microstructural changes may be involved in the phase transition regime. The materials yield stress appears lower when measured in a mini-Hopkinson bar (with very small samples) as compared with that measured by a 1/2-in. Hopkinson bar (with relatively large samples), possibly due to the sample size that may produce different deformation mechanisms within the superelastic strain range. The transition stress from the austenite to the martensite phase shows strain-rate sensitivity. This may be explained by considering the interfacial motion of the formed martensite phase, based on the thermally activated and dislocation-drag models. There exists a certain critical strain-rate level, at which the transition stress for the stress-induced martensite formation equals the yield stress of the austenite phase. Therefore, the shape-memory alloy deforms by the formation of stress-induced martensites, accompanied by the yielding of the martensite phase at this critical strain rate, while the material deforms plastically by the dislocation-induced plastic slip at strain rates above this critical level. 2004 Elsevier Ltd. All rights reserved.
Multilateralism and Democracy: A Dissent Regarding Keohane, Macedo, and Moravcsik

In an article printed last year in International Organization, Keohane, Macedo, and Moravcsik argued that multilateral organizations (MLO) could actually be good for democracy. We argue that KMM discount the prospect that MLO influence can be detrimental to democracies not because MLOs are “distant, elitist, and technocratic” but precisely because MLOs are highly political. International organizations have much to offer in improving the welfare of citizens and facilitating coordinations among states. They are not likely to improve procedural functions of democracies without a cost that itself is problematic for democracy.