cssi/SciSciGPT-SciSciNet huggingface dataset:
Uniaxial stress study of the quantum transitions in a strained layer (001) In0.21Ga0.79As/GaAs single quantum well

Abstract We have studied the effects of large, external uniaxial stress ( T ) along [100] and [110] on the optical properties of a strained layer (001) In 0.21 Ga 0.79 As/GaAs single quantum well (SQW). Because of the large stresses employed the observed energy shifts exhibit a nonlinear behavior due to the stress-induced coupling with the spin-orbit split band. For T ∥[110] the piezoelectric coupling produces an electric field along [001] which has a significant effect on both the energies and intensities of the various intersubband transitions.
Multiplanar Reconstruction of Three-Dimensional Transthoracic Echocardiography Improves the Presurgical Assessment of Mitral Prolapse

Background The aim of this study was to evaluate the value and accuracy of multiplanar reconstruction (MPR) of three-dimensional (3D) transthoracic echocardiographic data sets in assessing mitral valve pathology in patients with surgical mitral valve prolapse (MVP). Methods Sixty-four patients with surgical MVP and preoperative two-dimensional (2D) and 3D transthoracic echocardiography were analyzed. The descriptions obtained by 3D MPR and 2D were compared in the context of the surgical findings. Results Two-dimensional echocardiography correctly identified the prolapsing leaflets in 32 of 64 patients and 3D MPR in 46 of 64 patients ( P = .016). Among the 27 patients with complex pathology (ie, more than isolated middle scallop of the posterior leaflet prolapse), 3D MPR identified 20 correctly, as opposed to 6 with 2D imaging ( P Conclusion Interpretation of 3D transthoracic echocardiographic images with MPR improved the accuracy of the description of the MVP compared with 2D interpretation. This added value of 3D MPR was most important in extensive and/or commissural prolapse.
An image analysis system for coaxially viewed weld scenes

We present a complete, working system for analyzing coaxially viewed robotic weld scenes. The analysis is cast in the form of a consistent labeling problem in which the objects are small image regions from a regular tesselation and the possible labels are base metal, electrode, gas cup, filler wire, weld bead, and weld pool. Local domain knowledge and measurements on the image function are used to produce an initial set of labeling probabilities. These are then adjusted by probabilistic relaxation using global domain knowledge to arrive at a final consistent labeling, which constitutes the image analysis. The primary goal of this analysis is a sufficiently accurate description of the size and shape of the weld pool to allow quality monitoring of the welding process. This represents a significant departure from the primary objectives of prior work in this area, most of which has focused on the seam tracking problem. Discussions with welding engineers indicate that they are anxious to acquire whatever information may be available. Thus, this system serves the secondary goal of providing some idea of what might be possible, given both relatively modest, and therefore affordable, resources and a real time performance requirement. In constructing and demonstrating a complete system, we provide useful insight into the engineering of such systems for practical applications, addressing attribute extraction, feature selection, and statistical region classification. A novel, efficient near-optimal feature selection algorithm which we callratchet search is also presented. Finally, we discuss how such a system, which is quite robust, could be embedded into robotic welding systems to provide important weld quality analysis for process control.
A portable suction dredge for quantitative sampling in difficult substrates

A lightweight, portable suction dredge has been used for five bottom types which usually present problems to benthic investigators. Water depth ranged from 0.25 m to 5 m. By use of a 0.25 m2 quadrat or using the suction end as a probe with the depth of penetration limited by a collar, quantitative samples were taken in coarse sand, fine flocculent mud, dense turtle grass (Thalassia testudinum), sparse turtle grass over coralline rubble (Porites sp.) and carbonate rock with an overlay of shell rubble. The samples consisted of the material retained by a collecting bag attached to the suction dredge. None of the commonly used benthic sampling devices could obtain samples at all stations.
Communication in a hierarchical network

An analogy is drawn between a hierarchical communication network and a pyramidal election system. An equation is derived relating the probability that a given person will vote for an issue to the probability that the elected officer will also vote for that issue. The equation contains the size of the population, the required majority ratio, and the number of stages in the election system as parameters.
A Novel System for Identification of Inhibitors of Rift Valley Fever Virus Replication

Rift Valley fever virus (RVFV) is a human and livestock pathogen endemic to sub-Saharan Africa. We have developed a T7-dependent system for the efficient production of RVFV-like particles (RVF-VLPs) based on the virulent ZH-501 strain of RVFV. The RVF-VLPs are capable of performing a single round of infection, allowing for the study of viral replication, assembly, and infectivity. We demonstrate that these RVF-VLPs are antigenically indistinguishable from authentic RVFV and respond similarly to a wide array of known and previously unknown chemical inhibitors. This system should be useful for screening for small molecule inhibitors of RVFV replication.
Shrimp Antimicrobial Testing. II. Toxicity Testing and Safety Determination for Twelve Antimicrobials with Penaeid Shrimp Larvae

Abstract The need for federally approved chemotherapeutants for use in domestic shrimp culture in the USA is acute. A summary of toxicity testing of 12 antimicrobials against penaeid shrimp larvae is presented. In addition, the toxicity data are examined in concert with previously reported data on minimum inhibitory concentrations to establish a therapeutic index (a measure of margin of safety) for each compound tested. The 11 prospective antimicrobials were compared with the reference compound, chloramphenicol. The antimicrobials tested were enrofloxacin, erythromycin, florfenicol, oxytetracycline, paromomycin, four experimental fluoroquinolines (PD124816, PD127391, PD131628, PD132133), Romet-30®, and Sarafin®. The top six compounds (in their relative order of safety, from the safest to the least safe) were PD127391, oxytetracycline, chloramphenicol, enrofloxacin, florfenicol, and Romet-30.
Simulation of Radionuclide Migration in Groundwater Away from an Underground Nuclear Test

Reactive transport simulations are being used to evaluate the nature and extent of radionuclide contamination within alluvium surrounding an underground nuclear test at the Nevada Test Site (NTS). Simulations are focused on determining the abundance and chemical nature of radionuclides that are introduced into groundwater, as well as the rate and extent of radionuclide migration and reaction in groundwater surrounding the working point of the test. Transport simulations based upon a streamline-based numerical model are used to illustrate the nature of radionuclide elution out of the near-field environment and illustrate the conceptual modeling process. The numerical approach allowed for relatively complex flow and chemical reactions to be considered in a computationally efficient manner. The results are particularly sensitive to the rate of melt glass dissolution, distribution of reactive minerals in the alluvium, and overall groundwater flow configuration. They provide a rational basis from which defensible migration assessments can proceed.
Infrared imaging arrays based on superlattice photodiodes

We report on the status of focal plane arrays (FPAs) based on GaSb/InAs type-II superlattice diodes grown by molecular beam epitaxy (MBE) and designed for infrared absorption in the 2-5μm and 8-10μm bands. Recent LWIR devices have produced differential resistance-area product greater than 100 Ohmcm2 at 80K with a long wavelength cutoff of approximately 10μm. The measured quantum efficiency of these front-side illuminated devices is close to 25% in the 8-9 μm range. MWIR devices have produced detectivities as high as 8x1013 Jones with a differential resistance-area product greater than 3x107 Ohmcm2 at 80K with a long wavelength cutoff of approximately 3.7μm. The measured quantum efficiency of these front-side illuminated MWIR devices is close to 40% in the 2-3μm range at low temperature and increases to over 60% near room temperature. Initial results on SiO2 and epitaxial-regrowth based passivation techniques are also presented, as well as images from the first lot of 1kx1k MWIR arrays and our latest 256x256 LWIR arrays.
Structure of Hawaiian volcanoes from seismic refraction data

Numerous seismic refraction traverses were carried out over the Hawaiian Islands to outline the structure of the volcanoes and determine the thickness of the layers of the crust. Results indicate that there is a progressive thickening of the crust in the area from younger to older volcanic islands. High velocity mantle-like material was detected under rift zones and in volcanic plugs. Volcanic regions were found to be intersected by flexure zones in the crust and in the mantle.
Dropwise evaporation : thermal analysis of multidrop systems

Abstract This paper investigates the heat transfer from a heated solid surface to droplets evaporating in the low superheat regime, where the droplets stick onto the surface without bubble nucleation. The model consists of a regular array of identical droplets interacting thermally through the solid. Analytical expressions for the Nusselt number involving a power series of κ 1 2 , where κ is the fraction of the solid surface wetted by the droplets, are derived. It is found that droplet interactions cannot, in general, be ignored. Furthermore, the strength of these interactions is a function of droplet contact angle, solid conductivity, and droplet concentration.
Nature’s bioreactor: the rumen as a model for biofuel production

As a major component of the plant cell wall, cellulose is the most abundant source of terrestrial carbon and therefore attractive for biofuel production. However, current industrial efforts to convert plant biomass into biofuels have been hampered because plant polysaccharides such as cellulose and hemicelluloses are difficult to break down and the fermentation of the resulting sugars is not efficient. Natural systems that hydrolyze and ferment cellulose could therefore inform these industrial efforts. The rumen, as part of the digestive tract in some herbivores, houses a microbial community that naturally and efficiently hydrolyzes cellulose and ferments the resulting sugars to products that are precursors to biofuels. Genomic and metagenomic sequencing of the rumen microbial community is leading to the discovery of fibrolytic enzymes and the identification of the multiple approaches used by rumen microbes to digest cellulosic substrates. These sequencing efforts are also identifying microbial interactio...
Wound closure: evidence of cooperation between fibroblasts and collagen matrix

The closure of severe wounds where viable tissue has been destroyed by trauma involves the depositing of a new connective tissue matrix, the amount of which is dictated by the severity of trauma. That new connective tissue matrix is immature, and in some cases, can reduce itself. When this occurs in a healing wound it is called wound contraction. When it occurs in the scar of a healed wound, it is called scar contracture. Forces generated in fibroblasts organise the surrounding connective tissue matrix, and this is responsible for the contraction of wounds and the contracture of scars. The experimental work presented here supports the idea that these contractile forces residing in the fibroblast work as individual units to contract the wound. There is no evidence to support the idea of the myofibroblast, a specialised cell, being responsible for contractile forces, as reported. The morphological appearance of stress fibres, which denote the presence of myofibroblasts, may, in fact, signify the termination of the generation of contractile forces. Control of cellular contractile forces appears to be linked to the composition of the connective tissue matrix. A matrix rich in type III collagen contracts faster and to a greater degree than one made from type I collagen. It is suggested that granulation tissue and immature scar with a matrix rich in type III collagen will contract more readily than a more mature scar with less type III collagen. Evidence presented from in vitro models suggests that fibroblasts generate the forces of contraction, and collagen controls those forces in wound closure and scar contracture.
Gonadal hormones do not alter the development of antinociceptive tolerance to delta-9-tetrahydrocannabinol in adult rats

Abstract The purpose of this study was to determine whether sex differences in the development of antinociceptive tolerance to delta-9-tetrahydrocannabinol (THC) are due to activational effects of gonadal hormones. Rats were sham-gonadectomized (sham-GDX) or gonadectomized (GDX). GDX females received no hormone replacement (GDX + 0), estradiol (GDX + E2), progesterone (GDX + P4), or both (GDX + E2/P4). GDX male rats received no hormone (GDX + 0) or testosterone (GDX + T). Two weeks later, antinociceptive potency of THC was determined (pre-chronic test) on the warm water tail withdrawal and paw pressure assays. Vehicle or a sex-specific THC dose (females, 5.7 mg/kg, males, 9.9 mg/kg) was administered twice-daily for 9 days, then the THC dose–effect curves were re-determined (post-chronic test). On the pre-chronic test (both assays), THC was more potent in sham-GDX females than males, and gonadectomy did not alter this sex difference. In GDX females, P4 significantly decreased THC's antinociceptive potency, whereas E2 had no effect. In GDX males, T did not alter THC's antinociceptive potency. After chronic THC treatment, THC's antinociceptive potency was decreased more in sham-GDX females than males, on the tail withdrawal test; this sex difference in tolerance was not altered in GDX or hormone-treated groups. These results suggest that greater antinociceptive tolerance in females, which occurred despite females receiving 40% less THC than males, is not due to activational effects of gonadal hormones.
On the Cauchy problem for an elliptic system

It is well known that the Cauchy problem for the Laplace equation is not well posed in the sense of HADAMnRO, i.e., the solution does not depend continuously on the Cauchy data. Recently mathematicians have renewed interest in Cauchy problems that are not well posed since some physical situations actually correspond to such problems [33]. Much of this attention has been devoted to the study of the uniqueness of the solution [1, 2, 4 -8 , 10-33, 35-38]. To derive stability results, PuccI [31] imposed a uniform bound on the solution of the Cauchy problem for an elliptic equation. Under this assumption, LAU~NTIEV [17] demonstrated that the solution of the Cauchy problem for the Laplace equation depends continuously on the Cauchy data. Based upon these works, PAYN~ [26] presented a method for obtaining pointwise bounds for the solution of the Cauchy problem for the Laplace equation in N dimensions. He has extended this technique to an elastic plate problem [27] and to a general second order uniformly elliptic operator [28]. In the elastic plate problem PAYN~ assumed that the Laplacian of the solution was also uniformly bounded. TRYTT~N [36] extended these results to a general nonlinear second order uniformly elliptic equation. Presently, we obtain uniqueness and stability results by means of the method of PAYNE and TRYTTEN for the Cauchy problem for the nonlinear system
Cyclic formation of debris avalanches at Mount St Augustine volcano

VOLCANIC debris avalanches have been seen at many volcanoes since the 1980 eruption of Mount St Helens, but typically only one or two avalanche deposits are identified at each eruptive centre, suggesting that catastrophic slope failures are rare or even unique events in the lifetime of a volcano1–4 Here we present a series of radiocarbon dates from volcanic deposits showing that the summit edifice of Mount St Augustine, a 1,220-m-high active volcano on Augustine Island in the Cook Inlet area of south-central Alaska, has repeatedly collapsed and regenerated, averaging 150–200 years per cycle, during the past 2,000 years. The unprecedented frequency of summit edifice failure was made possible by sustained lava effusion rates over 10 times greater than is typical of plate-margin volcanoes.
Parental and perinatal factors influencing the development of handedness in captive chimpanzees

It has been proposed that human right handedness is determined by genetic factors associated with the emergence of language, whereas non-human primate handedness is determined by random, non-genetic factors. These different mechanisms account for differences in the distribution of handedness between human and non-human primates. Here we report evidence that genetic factors play a role in the determination of handedness in chimpanzees. We further report that differential rearing has no influence on the expression of handedness in related individuals. Contrary to many theories of the origin of handedness, these results indicate that genetic factors have a significant influence on handedness in chimpanzees.
The effect of cortisone and corticotropin on the biologic decay of thyroidal radioiodine.

SEVERAL recent studies have been interpreted as showing that cortisone and corticotropin induce hypothyroidism by suppressing the secretion of thyrotropin by the pituitary (Hill et al., 1950; Frederickson, 1951). The evidence for this conclusion has been reviewed in detail elsewhere (Albert, 1952). Part of this evidence is the observation that I131 uptake by the thyroid in both animals and man is diminished during administration of either corticotropin or cortisone. If thyroid function is defined in terms of the accumulation of I131 over a given interval (a poor definition), then it could be said that both cortisone and corticotropin reduce thyroid function. However, it would not necessarily follow that such a depression of thyroid function resulted from suppression of thyrotropin, since there are many possible explanations for the reduction of I131 accumulation apart from any alteration in the secretion of thyrotropin. In evaluating studies with I131 the definition of “thyroid function” becomes of paramo...
Skeletal change in response to altered strain environments: Is woven bone a response to elevated strain?

Abstract Studies demonstrate that geometric changes in bone architecture in response to altered mechanical strain occur through the formation of woven bone. The goal of this study was to test the hypothesis that these changes are partly the result of surgical manipulation rather than a true adaptive response to altered strain. Beagle dogs were subjected to either an ulnar osteotomy, an osteotomy with plate fixation, or sham operation. Strains on the radius were measured just prior to sacrifice 1, 3 or 6 months after surgery. Our results support the idea that woven bone can be a normal response to an abnormal strain environment if the mechanical challenge is intense enough; that elevated mechanical strains can cause the endocortical bone envelope to revert to a state of net formation; and that “adaptive remodeling” in adults in response to a change in mechanical strain may be a special case of modeling in which resorption is not required prior to formation at a particular skeletal site.
Oxidation catalysis in air with Cp*Ir: influence of added ligands and reaction conditions on catalytic activity and stability

We describe the systematic evaluation of Cp*Ir catalysts for the aerobic oxidation of alcohols. Our results demonstrate turnover numbers up to 270 per [Cp*IrCl2]2 which have not been previously achieved for this reaction. Using air as the sole oxidant under base-free conditions, the effects of solvent systems and additives on the catalytic activity are documented systematically. We further elucidate the role of additives in catalyst decomposition processes and establish a novel buffer system which results in significant catalyst stabilization upon prolonged reaction times.
Comparative ecophysiology of Chrysanthemum pacificum Nakai and solidago altissima L. 1. why S. altissima cannot be established on the seashore

A fieldsurvey was made to elucidate whether salt spray is a major factor in preventing a common inland weed,Solidago altissima, from being established on the seashore of Boso Peninsula. Seasonal changes in the intensity of salt spray, sodium content in the soil water and soil water contents were measured at the seashore and inland. Seeds ofS. altissima were sown at both sites with those of a common maritime species,Chrysanthemum pacificum. The number of surviving shoots of the seedlings were periodically counted for 1 year. The intensity of the salt spray, sodium content and water contents of the soil on the seashore fluctuated seasonally. There were some periods when the intensity of salt spray was comparable to that of the inland site. Most of theS. altissima seedlings survived at the inland site. AllS. altissima seedlings germinated at the seashore were completely eliminated. The death rate ofS altissima seedlings at the seashore was not constant. Ninety-five percent of theS. altissima seedling in total died out during the four periods of intensive salt spray. The death rate ofC. pacificum seedlings on the seashore was not especially high during those periods. Correlation between seasonal changes in the death rate ofS. altissima seedlings and the sodium content or water content of the soil was low. These results indicate that intensive salt spray, intermittently blown in from the sea, is one of the most critical environmental factors that eliminatesS. altissima from the seashore.
Simultaneous optical recording of evoked and spontaneous transients of membrane potential and intracellular calcium concentration with high spatio-temporal resolution

Abstract We have developed a system for simultaneous optical recording of transients of membrane potential and intracellular calcium concentration from mammalian brain slice preparations with high spatio-temporal resolution. Simultaneous recording was achieved by using two dedicated photodetectors together with two fluorescent indicators. Specifically, the calcium-sensitive dye Calcium Orange and the voltage-sensitive dye RH-414 were selected because they have overlapping excitation spectra, but separable emission spectra. Transverse guinea pig hippocampal slices were double-loaded by bath application of the membrane-permeant form of Calcium Orange and RH-414. Transients of intracellular calcium concentration and membrane potential associated with evoked neural activity in hippocampal areas CA1 and CA3 were recorded. Furthermore, we have recorded calcium and voltage transients associated with spontaneous epileptiform activity induced by bath application of an epileptogenic drug, 4-aminopyridine. The use of photodiode matrices (10 × 10 elements each) as detectors gives the high spatial (200 × 200 μm/element with a 10 × objective) and temporal resolution (570 μs/frame). The recording system also includes a CCD camera for obtaining images of the preparation and overlaying the image with the optically detected signals. A software package has been developed for setting up the experimental protocol(s) and for collecting, processing, displaying, and analyzing the data in an user-friendly, windows-based environment.
Autonomous decision making in layered and Reconfigurable Video Coders

Layered compression and reconfigurable coding paradigms require coupled encoding decisions among layers or codec components in order to achieve optimal distortion performance under buffer constraints. Moreover, due to the dynamic and time-varying source characteristics, and temporal coupling of encoding decisions through the buffer constraints, both the immediate and long-term rate-distortion impact of encoding decisions must be considered. In many scenarios, however, it may be impractical to make such joint coding decisions. To address this problem, we propose a framework for autonomous decision making in layered and reconfigurable coders, which decouples the decision making processes of the various layers or codec components using a layered Markov decision process.
AMENITY BENEFITS AND PUBLIC POLICY: AN APPLICATION TO THE CONNECTICUT DAIRY SECTOR

This article develops a conceptual framework for analyzing the role of state-level policies towards the dairy sector in the presence of farmland amenity benefits, and applies it to Connecticut. Milk supply, demand and amenity benefit functions are estimated, and three exogenously determined milk prices are considered. The empirical findings show, under each price scenario, the extent to which land is underallocated to the dairy sector if amenity benefits are ignored. Analysis of policy options reveals that a partial production cost subsidy represents the least-cost alternative for attaining the socially optimal solution for the region.
Design and fabrication of an angular microactuator for magnetic disk drives

Angular electrostatic microactuators suitable for use in a two-stage servo system for magnetic disk drives have been fabricated from molded chemical-vapor-deposited (CVD) polysilicon using the HexSil process. A 2.6-mm-diameter device has been shown to be capable of positioning the read/write elements of a 30% picoslider over a /spl plusmn/1-/spl mu/m range, with a predicted bandwidth of 2 kHz. The structures are formed by depositing polysilicon via CVD into deep trenches etched into a silicon mold wafer. Upon release, the actuators are assembled onto a target wafer using a solder bond. The solder-bonding process will provide easy integration of mechanical structures with integrated circuits, allowing separate optimization of the circuit and structure fabrication processes. An advantage of HexSil is that once the mold wafer has undergone the initial plasma etching, it may be reused for subsequent polysilicon depositions, amortizing the cost of the deep-trench etching over many structural runs and thereby significantly reducing the cost of finished actuators. Furthermore, 100-/spl mu/m-high structures may be made from a 3-/spl mu/m deposition of polysilicon, increasing overall fabrication speed.
Early Child Risk Factors for Externalizing and Internalizing Behaviors: A 5-Year Follow-Forward Assessment

The purpose of this follow-forward study was to determine if behavioral groupings, created when children were preschoolers, were associated with different outcomes 5 years later. Participating in this follow-forward study were parents of three groups of children who participated in a larger study 5 years earlier. Children had been identified as preschoolers with hyperactivity, hyperactivity and aggression, or comparisons. Response rate for the follow-forward study was 66% and attrition rates were similar across the groups. Parents completed the Child Behavior Checklist (CBCL) at the outcome assessment. Analyses were conducted to determine if the original groups could be differentiated on the CBCL factors 5 years later. Results from this study clearly illuminated the importance of early assessments of hyperactivity and aggression, as they were associated with later behavior problems.
The health pros and cons of continuous versus intermittent calorie restriction: More questions than answers

Beneficial effects on health of limiting food intake for certain periods of time have been recognized for a long time. While many diets can produce short-term weight loss, most fail to result in a long-lasting impact. Current data suggest that intermittent fasting may be beneficial for overall health and wellbeing. However, the lack of properly designed clinical studies makes it challenging to formulate evidence-based practice recommendations. Potential health risks of drastic changes in food intake are often ignored and might only be revealed after extensive follow-up. This review summarizes the popular intermittent dieting methods and their potential impact on fertility and reproduction.
Model for degradation of GaAs/AlGaAs HBTs under temperature and current stress

The similarities between GaAs/AlGaAs heterojunction bipolar transistors (HBTs) and GaAs-based light-emitting diodes (LEDs) and laser diodes (LDs) under current and temperature stress are demonstrated. Electroluminescence on HBTs with degraded current gain shows a marked decrease in light emission. One device which suffered rapid degradation in current gain also showed a dark line defect (DLD). Finally, an equation used to model light output as a function of time under bias stress in LEDs and LDs was modified to model collector current vs. time for HBTs under bias stress. An excellent fit to the data is shown.
An In Vitro Investigation Into the Effects of Repetitive Motion and Nonsteroidal Antiinflammatory Medication on Human Tendon Fibroblasts

Soft tissue injuries due to repetitive motion are common sports injuries and are often treated with antiinflamma tory therapies. We investigated the in vitro effects of repetitive motion and nonsteroidal antiinflammatory medication on human tendon fibroblasts. In addition, we studied the effects related to the presence of inflam matory cells. Repetitive motion was associated with an increased release of prostaglandin E2 and increased deoxyribonucleic acid (DNA) and protein synthesis. The presence of nonsteroidal antiinflammatory medication decreased prostaglandin E2 release and DNA synthe sis but increased protein synthesis. Contact with mac rophages caused a marked additional increase in pros taglandin E2 and a concomitant increase in DNA synthesis. Release of interleukin-6 by the macrophages also suggested that this cytokine plays a role in the re sponse to repetitive motion. Our results can aid in the search for a more scientific approach to the treatment of soft tissue injuries associated with repetit...
Differential Importance of Hierarchical Learning, Abstractness, and Imagery

This research examined the relative contribution of hierarchical sequencing, abstractness, and imagery to learning. In the past, hierarchical, logical sequencing was not shown to be superior to other modes of instruction, and the interaction of imagery, abstractness, and sequencing had not been examined, especially regarding the possible superiority of any of these as a contributor to learning. The data were produced by 108 high school students who studied sequences of hierarchically related information arranged in a 2 x 2 x 2 factorial design the dimensions of which varied according to the degree of imagery (high and low), abstractness (abstract and concrete), and type of sequencing (logical and scrambled). Analyses of the amount of learning under these conditions showed that hierarchical sequencing is not only relevant to learning but more related than either imagery or the abstractness of material to be learned. Additional suggestions are made regarding instruction and research especially in relation to matrix rather than hierarchial arrangements of information.
Social Engagement and Physical and Cognitive Health Among American Indian Participants in the Health and Retirement Study

Social engagement has many demonstrated benefits for aging non-Hispanic Whites in the U.S. This study examined data from the U.S. Health and Retirement Study to determine whether these benefits were similar among American Indians and Alaska Natives older than 50 years. Linear regression techniques were used to examine the associations between level of social engagement, scores for memory and mental status, and self-reported health among 203 American Indian and Alaska Native elders who participated in the Health and Retirement Study and had data available between 1998 and 2010. Level of social engagement was significantly associated with memory, mental status, and self-reported health. However, only the association of social engagement with mental status and self-reported health remained significant (p = 0.04 and p = 0.05, respectively) after adjusting for sociodemographic variables, number of known health conditions, and scores on the Center for Epidemiologic Studies Depression scale. Level of social engagement was not associated with patterns of decline across time in cognitive or physical health. Higher levels of social engagement are associated with better physical and cognitive functioning in American Indian and Alaska Native elders. Future studies should examine whether this association acts through cognitive stimulation, increase in physical activity resulting from social engagement, or access to resources that support physical and cognitive health.
A combinatorial optimization framework for subset selection in distributed multiple-radar architectures

Widely distributed multiple radar architectures offer parameter estimation improvement for target localization. For a large number of radars, the achievable localization minimum estimation mean-square error (MSE), with full resource allocation, may extend beyond the system predetermined performance goals. In this paper, a performance driven resource allocation scheme for multiple radar systems is proposed. The number of transmit and receive radars employed in the estimation process is minimized by effectively selecting a subset of active radars such that the required MSE performance threshold is attained. As the goal is to obtain a performance level with the lowest cost, in terms of active system elements, the problem is formulated in a combinatorial optimization framework as a knapsack problem (KP). The Cramer-Rao bound (CRB) is used as a performance metric. Cost parameters, representing operational cost or any other utilization constraints on the radars, are associated with each of the radars. These are incorporated in the KP formulation, as decision making factors in the selection process. Radar subset selection is implemented through a heuristic algorithm, successively selecting radars that minimize the performance gap between the temporal CRB and a given MSE goal. The proposed algorithm offers considerable reduction in computational complexity when compared with an exhaustive search. By minimizing the number of operational radars needed to complete the task, this concept introduces savings in both communication link needs and central processing load, in addition to the operational ones.
Enzymnachbildungen auf der Basis supramolekularer Koordinationschemie

In der aktuellen supramolekularen Koordinationschemie konnen makromolekulare Komplexe mit Enzymeigenschaften synthetisiert werden. Dieser Aufsatz behandelt solche Strukturen, die nicht in erster Linie die aktiven Zentren von Enzymen nachbilden sollen, sondern von deren Eigenschaften und Funktionen inspiriert sind. Die Komplexe werden in konvergenter Weise mit modularen Methoden in hohen Ausbeuten synthetisiert, wobei ihre Grose, Form und Eigenschaften masgeschneidert werden konnen. Viele der Strukturen zeigen eine Reaktivitat und Spezifitat, die an naturliche Systeme erinnern, und manche haben Funktionen, die uber jene ihrer Vorbilder hinausgehen.
Lasso tree for cancer staging with survival data

The tumor-node-metastasis staging system has been the lynchpin of cancer diagnosis, treatment, and prognosis for many years. For meaningful clinical use, an orderly grouping of the T and N categories into a staging system needs to be defined, usually with respect to a time-to-event outcome. This can be reframed as a model selection problem with respect to features arranged on a partially ordered two-way grid, and a penalized regression method is proposed for selecting the optimal grouping. Instead of penalizing the L1-norm of the coefficients like lasso, in order to enforce the stage grouping, we place L1 constraints on the differences between neighboring coefficients. The underlying mechanism is the sparsity-enforcing property of the L1 penalty, which forces some estimated coefficients to be the same and hence leads to stage grouping. Partial ordering constraints is also required as both the T and N categories are ordinal. A series of optimal groupings with different numbers of stages can be obtained by varying the tuning parameter, which gives a tree-like structure offering a visual aid on how the groupings are progressively made. We hence call the proposed method the lasso tree. We illustrate the utility of our method by applying it to the staging of colorectal cancer using survival outcomes. Simulation studies are carried out to examine the finite sample performance of the selection procedure. We demonstrate that the lasso tree is able to give the right grouping with moderate sample size, is stable with regard to changes in the data, and is not affected by random censoring.
Site Condition, Structure, and Growth of Baldcypress Along Tidal/Non-Tidal Salinity Gradients

This report documents changes in forest structure and growth potential of dominant trees in salt-impacted tidal and non-tidal baldcypress wetlands of the southeastern United States. We inventoried basal area and tree height, and monitored incremental growth (in basal area) of codominant baldcypress (Taxodium distichum) trees monthly, for over four years, to examine the inter-relationships among growth, site fertility, and soil physico-chemical characteristics. We found that salinity, soil total nitrogen (TN), flood duration, and flood frequency affected forest structure and growth the greatest. While mean annual site salinity ranged from 0.1 to 3.4 ppt, sites with salinity concentrations of 1.3 ppt or greater supported a basal area of less than 40 m2/ha. Where salinity was < 0.7 ppt, basal area was as high as 87 m2/ha. Stand height was also negatively affected by higher salinity. However, salinity related only to soil TN concentrations or to the relative balance between soil TN and total phosphorus (TP), which reached a maximum concentration between 1.2 and 2.0 ppt salinity. As estuarine influence shifts inland with sea-level rise, forest growth may become more strongly linked to salinity, not only due to salt effects but also as a consequence of site nitrogen imbalance.
Critical comparison of the experimental optical activity of helical polypeptides and the predictions of the molecular exciton model.

The predictions of the presently accepted molecular exciton model for the optical activity of helical polypeptides are in reasonable agreement with experimental spectra in the accessible wavelength range. However, crucial verification requires the detect of a significant negative rotatory hand just below the accessible range. A computer-oriented method is utilized to obtain information concerning the inaccessible range. Optical rotatory dispersion computed by evaluation of the Kronig-Kramers integral transform from the experimentally determined circular dichroism of several helical homopolypeptides in solution are compared with the experimentally determined optical rotatory dispersion. Computed and experimental curves are congruent within an uncertainty approaching that of the experimental technique, whatever the polypeptide sample lot, side chains, and solvent. It is shown that t his agreement is not a computational or experimental artifact. These results can be interpreted in two ways: (1) that the predicted band does not exist, and (2) that the perturbation of the predicted band is being negated by other inaccessible bands in the vacuum ultraviolet. Arguments are presented to show that the first of these two possibilities is more probable.
Expression of endothelin 1 in rat random-pattern skin flaps treated with topical nifedipine.

Conclusions: The correlation between tissue levels of ET-1andtheseverityoftissuenecrosissuggeststhatET-1 mayplayapivotalroleinischemicinjuryofRPSFs.Moreover, treatment with topical nifedipine may antagonize the vasoconstrictive effects of ET-1. Although immunohistochemical analysis revealed ET-1 staining within the flap microvasculature, no quantitative differences were detectedbetweenthenifedipine-andplacebo-treatedflaps. Further studies are needed to define the role of ET-1 in RPSF necrosis.
Diffraction of a plane shock by an analytic blunt body

A study is made of the transient flow which results from the impingement of a plane shock on a blunt body. The analysis is based on Taylor-series expansions in the space and time variables of the flow properties and of the shape of the reflected shock. Coefficients of the series are determined numerically so as to satisfy the exact equations of motion and shock jump conditions. Convergence problems are ameliorated by recasting the series into continued fractions. While the analysis does not treat the transition from regular to Mach reflexion, it remains valid for all time in the subsonic region of the flow if the incident shock is sufficiently strong. In any case, it is accurate enough where it is valid to be useful for evaluation of more conventional numerical methods.
A constant daylength during the Precambrian era

The semidiurnal atmospheric thermal tide would have been resonant with free oscillations of the atmosphere when the day was approximately 21 h long, c. 600 Ma ago. Very large atmospheric tides would have resulted, with associated surface pressure oscillations in excess of 10 mbar in the tropics. Near resonance the Sun's gravitational torque on the atmospheric tide--accelerating Earth's rotation--would have been comparable in magnitude to the decelerating lunar torque upon the oceanic tides. The balance of the opposing torques may have long maintained a resonant approximately 21 h day, perhaps for much of the Precambrian. Because the timescale of lunar orbital evolution is not directly affected, a constant daylength would result in fewer days/month. The hypothesis is shown not to conflict with the available (stromatolitic) evidence. Escape from the resonance could have followed a relatively abrupt global warming, such as that occurring at the end of the Precambrian. Alternatively, escape may simply have followed a major increase in the rate of oceanic tidal dissipation, brought about by the changing topography of the world's oceans. We integrate the history of the lunar orbit with and without a sustained resonance, finding that the impact of a sustained resonance on the other orbital parameters of the Earth-Moon system would have not been large.
Putting first things first: critical issues for public administration education:

This article begins by reviewing developments in the field of public administration over the past 50 years and identifying factors that have served, in some cases unintentionally, to undermine publ...
The Genetics of Parkinson Disease

Parkinson disease (PD) is the second most common neurodegenerative disorder. In most instances, PD is thought to result from a complex interaction between multiple genetic and environmental factors, though rare monogenic forms of the disease do exist. Mutations in 6 genes (SNCA, LRRK2, PRKN, DJ1, PINK1, and ATP13A2) have conclusively been shown to cause familial parkinsonism. In addition, common variation in 3 genes (MAPT, LRRK2, and SNCA) and loss-of-function mutations in GBA have been well-validated as susceptibility factors for PD. The function of these genes and their contribution to PD pathogenesis remain to be fully elucidated. The prevalence, incidence, clinical manifestations, and genetic components of PD are discussed in this review.
3D Scene Understanding by Voxel-CRF

Scene understanding is an important yet very challenging problem in computer vision. In the past few years, researchers have taken advantage of the recent diffusion of depth-RGB (RGB-D) cameras to help simplify the problem of inferring scene semantics. However, while the added 3D geometry is certainly useful to segment out objects with different depth values, it also adds complications in that the 3D geometry is often incorrect because of noisy depth measurements and the actual 3D extent of the objects is usually unknown because of occlusions. In this paper we propose a new method that allows us to jointly refine the 3D reconstruction of the scene (raw depth values) while accurately segmenting out the objects or scene elements from the 3D reconstruction. This is achieved by introducing a new model which we called Voxel-CRF. The Voxel-CRF model is based on the idea of constructing a conditional random field over a 3D volume of interest which captures the semantic and 3D geometric relationships among different elements (voxels) of the scene. Such model allows to jointly estimate (1) a dense voxel-based 3D reconstruction and (2) the semantic labels associated with each voxel even in presence of partial occlusions using an approximate yet efficient inference strategy. We evaluated our method on the challenging NYU Depth dataset (Version 1 and 2). Experimental results show that our method achieves competitive accuracy in inferring scene semantics and visually appealing results in improving the quality of the 3D reconstruction. We also demonstrate an interesting application of object removal and scene completion from RGB-D images.
Pineal regulation of immunoreactive luteinizing hormone and prolactin in light-deprived female hamsters.

The influence of light deprivation pinealectomy and pineal denervation on pituitary and plasma levels of luteinizing hormone (LH) and prolactin in 62 adult female hamsters was studied. 46 of the hamsters were blinded by bilateral orbital enucleation. 10 of the blinded animals were pinealectomized and 11 were superior cervical ganglionectomized. After 8 weeks 12 blinded and 8 intact hamsters received 4-mcg LH-releasing hormone (RH)/day for 1 week after which all animals were necropsied. Immunoreactive LH and prolactin levels were determined by double antibody radioimmunoassays. The blinded hamsters had significantly higher levels of LH within the pituitary than the normal controls (p less than .001). Pituitary prolactin levels in the blinded were significantly decreased (p less than .001). LH-RH treatment did not markedly alter LH or prolactin levels in the pituitary. Plasma LH of the blinded hamsters was about twice as high as the controls. LH-RH did significantly raise plasma LH in the intact and blinded (p less than .01 and p less than .02 respectively). Blinded hamsters that were pinealectomized or ganglonectomized had LH and prolactin levels comparable to the controls. Plasma prolactin levels were only slightly altered among the 6 experimental groups.
Women with Beards and Men in Frocks: Gender Nonconformity in Modern American Film

The present study examines the portrayal of gender nonconformity in 36 American films released from 2001 to 2011. Mainstream and independent films with at least one character portrayed in a gender transgressive way were chosen for analysis. The films were coded at two levels: (1) the entire film, and (2) the individual characters. The entire films were coded for mainstream versus independent production, genre, and screen time of gender nonconforming characters. The characters were coded for the type of gender transgression, the characters’ demographics, and their purposes in the plot. The most common purpose of the non-conforming characters was humor, especially in mainstream films. Exploring identity was a much less common purpose and these films were far more likely to be independent films. The non-conforming characters were far more likely to identify as a static identity, man or woman, rather than anything else. Gender identity was almost always presented as something simple, static and binary.