cssi/SciSciGPT-SciSciNet huggingface dataset:
An experimental investigation on the effects of Web-based instruction/training on cognitive and psychomotor learning

The purpose of this study was to investigate the effects of web-based instruction (WBI) on cognitive and psychomotor learning. The subjects of the study received two types of instructional methods, WBI (experimental group) and traditional classroom instruction (control group). Each group received 30 minutes of instruction on "Soldering a Circuit Board." The researcher chose this content subject because it involved both cognitive and psychomotor objectives, which suited the purpose of this study. It was hypothesized that there would be no significant difference between the two methods of instruction, and also that there would be no significant interaction effects between methods of instruction and gender. Forty-six subjects from a population of students enrolled in summer classes offered by the Applied Technology, Training and Development (ATTD) program at the University of North Texas voluntarily participated in this study. Random assignment of subjects was applied in this study. A subject matter expert delivered the content for both the experimental and control groups. To measure cognitive variable, a 10 item, multiple-choice test was administered immediately after instruction. To measure the psychomotor variable, a 15-item checklist was utilized by trained judges to evaluate learners performances while soldering. The 2 x 2 factorial model with interaction was used in this study. The analysis was run for each of the dependent variables, cognitive and psychomotor learning. Although there was not a statistically significant difference in the main effects of method of instruction or interaction effects between method and gender, the results imply that students in the traditional-classroom instruction group performed better than those in the WBI group in psychomotor learning. Perhaps, this trend would be statistically significant if the sample size were larger. This study provides empirical evidence for the effectiveness of WBI in delivering cognitive and psychomotor objectives. The outcome of this study supports the need for more research on the effects of WBI on learning domains.
Euler calculations for a complete aircraft

We describe a new finite element method for solving the Euler equations, and present the results of a transonic flow calculation for a commercial aircraft with pylon mounted engines. The finite element method uses a tetrahedral mesh, and establishes conservation of mass, momentum and energy in polyhedral control volumes by summing fluxes through the faces of the tetrahedra. The tetrahedra are generated by using a DeLaunay triangulation to connect a swarm of mesh points surrounding the aircraft.
Context-Dependent Smooth Eye Movements Evoked by Stationary Visual Stimuli in Trained Monkeys

The appearance of a stationary but irrelevant cue triggers a smooth eye movement away from the position of the cue in monkeys that have been trained extensively to smoothly track the motion of movi...
Kinetics of biosynthesis of iron-regulated membrane proteins in Escherichia coli.

Using biological iron chelators to control specifically iron availability to Escherichia coli K-12 in conjunction with radioactive pulse-labels, we examined the biosynthesis of six iron-regulated membrane proteins. Iron deprivation induced the synthesis of five proteins, which had molecular weights of 83,000 (83K), 81K (Fep), 78K (TonA), 74K (Cir), and 25K. The kinetics of induction were the same in entA and entA + strains, but were affected by the initial iron availability in the media. Iron-poor cells induced rapidly (half-time, 10 min), whereas iron-rich cells began induction after a lag and showed a slower induction half-time (30 min). Within this general pattern of induction after iron deprivation, several different kinetic patterns were apparent. The 83K, 81K, and 74K proteins were coordinately controlled under all of the conditions examined. The 78K and 25K proteins were regulated differently. The synthesis of a previously unrecognized 90K inner membrane protein was inhibited by iron deprivation and stimulated by iron repletion. Both ferrichrome and ferric enterobactin completely repressed 81K and 74K synthesis when the siderophores were supplied at concentrations of 5 μM in vivo (half-time, 2.5 min). At concentrations less than 5 μM, however, both siderophores repressed synthesis only temporarily; the duration of repression was proportional to the amount of ferric siderophore added. The half-lives of the 81K and 74K mRNAs, as measured by rifampin treatment, were 1.2 and 1.6 min, respectively. The results of this study suggest that enteric bacteria are capable of instantaneously detecting and reacting to fluctuations in the extracellular iron concentration and that they store iron during periods of iron repletion for utilization during periods of iron stress. Neither iron storage nor iron regulation of envelope protein synthesis is dependent on the ability of the bacteria to form heme. Images
Frequent nut consumption and decreased risk of cholecystectomy in women.

BACKGROUND Gallstone disease is a major source of morbidity in the developed countries. Nuts are rich in several compounds that may protect against gallstone disease. OBJECTIVE The association between nut intake and cholecystectomy was examined in a large cohort of women. DESIGN We prospectively studied nut (peanuts, other nuts, and peanut butter) consumption in relation to the risk of cholecystectomy in a cohort of 80,718 women from the Nurses' Health Study who were 30-55 y old in 1980 and had no history of gallstone disease. As part of the Nurses' Health Study, the women reported on questionnaires mailed to them every 2 y both their consumption of nuts and whether they had undergone cholecystectomy. The women were followed through 2000. RESULTS During 1,393,256 person-years of follow-up from 1980 to 2000, we documented 7831 cholecystectomies. After adjustment for age and other known or suspected risk factors, women who consumed > or =5 units of nuts (1 unit = 1 oz or 28.6 g nuts)/wk (frequent consumption) had a significantly lower risk of cholecystectomy (relative risk: 0.75; 95% CI: 0.66, 0.85; P for trend < 0.0001) than did women who never ate nuts or who ate <1 unit/mo (rare consumption). Further adjustment for fat consumption (saturated fat, trans fat, polyunsaturated fat, and monounsaturated fat) did not materially alter the relation. In analyses examining consumption of peanuts and other nuts separately, both were associated with a lower risk of cholecystectomy. CONCLUSION In women, frequent nut consumption is associated with a reduced risk of cholecystectomy.
Evaluation of in vivo behavior of ameroid ring constrictors in dogs with congenital extrahepatic portosystemic shunts using computed tomography.

Objective To evaluate the in vivo pattern of ameroid constrictor closure of congenital extrahepatic portosystemic shunts in dogs. Study Design Prospective study. Animals Dogs (n = 22) with congenital extrahepatic portosystemic shunts. Methods Contrast-enhanced computed tomography was performed immediately before, and at least 8 weeks after placement of ameroid ring constrictors. Plastic-encased ameroid constrictors were used in 17 dogs and metal constrictors in 5 dogs. Presence of residual flow through the portosystemic shunt, additional anomalous vessels, acquired shunts and soft tissue associated with the ameroid constrictor was recorded. Postoperative internal diameter was recorded for the 17 plastic constrictors. Correlations between internal diameter and pre- and postoperative serum protein concentration were analyzed. Results No ameroid constrictor closed completely: shunt occlusion was always dependent on soft tissue within the ameroid ring. Residual flow through the shunt was present in 4 dogs (18%), although this caused persistent elevation of shunt fraction in only 1 dog (dog 8). The change in ameroid constrictor internal diameter was not significantly correlated with serum protein concentration. Conclusions Complete shunt occlusion after AC placement is usually dependent on soft tissue reaction. Ameroid constrictors ≥5 mm diameter may not promote complete shunt occlusion.
Deposition of highly oriented low-stress ZnO films

Several-micron-thick layers of ZnO films were deposited on glass substrates. The films were grown by reactive DC magnetron sputtering from a zinc target. The films are highly oriented, as indicated by X-ray diffraction analysis, and the C-axis of the films is normal to the substrate. A moire deflectometer was built to determine the film stress by measuring the substrate curvature. The films have relatively low stress at higher deposition pressures. The acoustic coupling constant, k/sub t/, of the films was measured to be as high as 0.26, which is 90% the value for single-crystal ZnO. The dependence of film quality and stress on various deposition parameters such as pressure and power is presented. >
Bridge-gap buried digit-line for high density stacked DRAMs

Explores the interaction of design and process to achieve a manufacturable low digit-line resistance-a key element to DRAM (dynamic random access memory) speed and to minimizing overall process complexity. They propose an interaction between stacked DRAM design and process called the bridge-gap process for achieving low digit-line resistance while minimizing overall process complexity. A study of digit-line resistance as a function of word-line gap and digit-line poly-Si thickness indicates that there is a well-defined, poly-Si dependent forbidden gap which gives rise to high, variable, and even open digit-line resistance. After word-line (n-channel transistor) spacer formation, digit-line buried contact formation, and digit-line poly-Si deposition, this gap partially closes and so presents a deep trench, which the LPCVD (low pressure chemical vapor deposited) WSi/sub x/ cannot adequately cover. For a minimum digit-line poly-Si thickness that can withstand the WSi/sub x/ stress, word-line gaps are designed so that they are either less than (bridged digit-line) or greater than (gapped digit-line) the forbidden gap. >
EVALUATION OF MATHEMATICAL MODELS FOR ORDERED POLYCHOTOMOUS RESPONSES

In this paper, mathematical modeling is treated as distinct from curve fitting. Considerations of psychological reality behind our data are emphasized, and criteria such as additivity in a model its natural generalization to a continuous response model, satisfaction of the unique maximum condition and orderliness of the modal points of the operating characteristics of the ordered polychotomous responses are proposed. Strengths and weaknesses of mathematical models for ordered polychotomous responses that include the normal ogive model, the logistic model, the acceleration model and the family of ordered polychotomous models developed from Bock’s nominal model are observed and discussed in terms of such criteria. It was concluded that it will be better to leave Bock’s model as a nominal model as he intended it to be, without expanding it to ordered polychotomous models.
Archipelagic Diaspora, Geographical Form, and Hurston's Their Eyes Were Watching God

Drawing a distinction between culturally oriented and formally oriented geographical approaches to American literary studies, this essay frames Zora Neale Hurston's Their Eyes Were Watching God (1937) as engaging with the geographical form and spatial materiality of the vast archipelago that W. E. B. DuBois, in his description of the planetary color line, referred to as "the islands of the sea." The insular spaces upon which the novel relies include Key West, Palm Beach, the Caribbean, Hellas, the Malay Archipelago, and others. Each of these spaces exerts parallax influence upon Their Eyes's creation of the horizon-space that Janie, the novel's protagonist, uses to animate her geographical search for the unpresentable. Attentiveness to the novel's varied reliances on insular and archipelagic forms helps make accessible Their Eyes's investments in critiquing and ironizing the geoformally oriented underpinnings of US sovereignty. Finally, the essay suggests that cultivating a new geographical formalism-in complement to literary studies that rely on cultural geography-lends pivotal modes of legibility to literary texts as well as to reading practices. These modes of legibility have specific implications for the notion of diaspora as well as for the intense critical readings and rereadings Their Eyes has received during recent decades.
Laboratory evaluation of several chemicals for preservation of excess colostrum

Abstract The influence of several chemicals on fermentation and preservation of colostrum at 32 C was examined under laboratory conditions. Chemicals studied were sodium benzoate, sodium propionate, sodium formate, sodium acetate, benzoic acid, sorbitol, and gluconic acid lactone. Additions of sodium benzoate and benzoic acid resulted in a slower decrease in pH and maintenance of a more constant pH for 21 days than the control and colostrum with other additives. No differences were significant in nutrient breakdown between day 0 and 14 of fermentation although sodium benzoate and benzoic acid tended toward a lower protein degradation than most other treatments. Coliform counts at 14 days were reduced by all chemicals. For other microbial analyses, the most notable results were a reduced mold and yeast count with additions of sodium benzoate and benzoic acid.
Multiple aspects of the stress response under social evaluative threat: An electrophysiological investigation

Affective traits and states may be important moderators of stress reactivity, providing insight into stress-related consequences on cognitive functioning. This study assessed cognitive control processes using response-related brain electrical activities-the error-related negativity (ERN) and error positivity (Pe)-that are sensitive to trait and state affect. To assess the role of cognitive control in affective and cortisol reactivity to social evaluative threat, 55 undergraduates first completed a standard task designed to elicit the ERN in order to index 'baseline' error monitoring. Participants then performed a difficult mathematical task designed to elicit the ERN under conditions of exposed failure and social evaluation. Baseline ERN amplitude predicted future cortisol reactivity to social evaluative threat in highly punishment-sensitive individuals (high self-reported Behavioral Inhibition System: Carver and White [1994. Behavioral inhibition, behavioral activation, and affective responses to impending reward and punishment: the BIS/BAS scales. J. Pers. Soc. Psych. 67, 319-333], although the presence of outliers suggest the need for replication. The math stress ERN amplitude was diminished in direct relationship to trait (punishment sensitivity) and state (fear and shame) negative affect. Individuals high in punishment sensitivity also showed specific deficits in task performance following error feedback under stress. High state affect related to a larger Pe amplitude. Results are interpreted as consequences of different motivational and affective reactivities under social evaluative threat.
Cytogenetic study in multiple myeloma

Ten patients with multiple myeloma (MM) were studied cytogenetically, using the G-banding technique. It was found that five patients had a normal karyotype, whereas five patients exhibited various chromosomal abnormalities. The presence of marker chromosomes was a consistent finding. Among those, the 14q+ marker chromosome was present in three cases, partial or complete trisomy for 1q was detected in four cases, and chromosome #6 was involved in two cases. In one case the 14q+ marker chromosome was determined to result from a translocation between chromosomes #11 and #14. In one patient with Bence Jones kappa multiple myeloma, there was a translocation between chromosomes #2 and #8.
Negative Poisson’s ratio behavior of idealized elastomeric auxetic cellular structures for various carbon black nanoparticles loadings:

Auxetic materials exhibit a negative Poisson’s ratio behavior that makes them useful for a variety of structural applications by virtue of their ability to counterintuitively deform due to a reentrant cellular structure. This property allows the cellular material to expand laterally when pulled in the longitudinal direction or, conversely, contract laterally when compressed, with the manner of deformation of the internal structure depending upon the configuration of the cellular structure. The purpose of this research was to develop carbon black nanoparticle-reinforced natural rubber vulcanizates and to investigate the effects of carbon black reinforcement on the mechanical behavior of an idealized auxetic foam structure using modeling and numerical simulation techniques. This has been achieved by mechanically characterizing vulcanized natural rubber of various nanoparticle loadings and then using the test data to perform finite element (FE) simulations on the foam models. Material models have been develo...
Brittle fracture of low molecular weight polymers

A new model is presented to predict the fracture energy of polymers with molecular weights smaller than the threshold value for the formation of chain entanglements. A fracture mechanism is assumed that calls for the sliding of the polymer chains in a microscopic craze at the crack tip. The plastic work is related to the chain interpenetration distance, which has been derived from the solution of the Fokker-Planck equation. The predictions of the model agree with experimental data of the fracture energy of polystyrene.
Oasis: an overlay-aware network stack

Overlays have enabled several new and popular distributed applications such as Akamai, Kazaa, and Bittorrent. However, the lack of an overlay-aware network stack has hindered the widespread use of general purpose overlay packet delivery services [16, 29, 26]. In this paper, we describe the design and implementation of Oasis, a system and toolkit that enables legacy operating systems to access overlay-based packet delivery services. Oasis combines a set of ideas - network address translation, name resolution, packet capture, dynamic code execution - to provide greater user choice. We are in the process of making the Oasis toolkit available for public use, specifically, to ease the development of PlanetLab-based packet delivery services.
Economic and Agronomic Assessment of Deep Tillage in Soybean Production on Mississippi River Valley Soils

Using deep tillage to alleviate the adverse effects of deleterious soil physical properties has been tried many times. Consistent economic returns have been reported for in-the-row subsoiling of loamy sand and coarser soils and for deep loamy soils where the subsoil slit bisects the water flow channel during rainfall events where there is runoff. Recent reports of yield responses on clayey soils and silt loams led to a reassessment of subsoiling of these soils in Arkansas. A randomized complete block design was conducted at four locations with tillage treatments of conventional shallow, deep chisel, subsoil dry, subsoil wet, subsoil at 45° to planting direction, and paratill. Plots were harvested for grain. Economic analysis was performed using the Mississippi State Budget Generator (MSBG). The machinery complement was commensurate with that found on farms in the region. Net returns above total specified costs (NRAT) rather than above direct costs were calculated to reflect the decision framework of a producer. A profitable yield response was obtained from subsoiling in dry soil on deep alluvial clayey and silt loam soils but not on the thin loessial silt loams. Net returns to subsoiling wet were not significantly higher than those to conventional shallow tillage. Tillage with a chisel plow as deep as it could be operated (approximately 15 cm) was not a substitute for subsoiling because yield responses from deeper tillage were not comparable. The 45° subsoiling in dry soil tended to be superior to all other tillage treatments.
Dynamic method for determining the coefficient of transverse deformation of refractories at high temperatures

We developed a direct dynamic method and constructed apparatus for determining the coefficient of transverse deformation of refractory materials.
Modeling of optical alignment and metrology schemes used in integrated circuit manufacturing

The aim ofour work was to develop rigorous models to study various optical alignment and metrology schemes implemented in commercial tools. These schemes indude wafer alignment schemes in steppers and linewidth measurement schemes in optical microscopes. A simulator called METRO based on the models developed has been implemented to facilitate this task. Theoretical and experimental verification efforts have been performed to examine the validity of the simulation results and good agreement has been obtained. By utilizing METRO process engineers can gain more insight into the equipment under operation so as to obtain more accurate alignment and measurement results. Also the equation formulation in METRO is general enough so that optics designers can easily adopt or modify the code to help in devising innovative alignment and metrology schemes. 1.
The Logarithmic Sobolev and Sobolev Inequalities Along the Ricci Flow

Based on Perelman’s entropy monotonicity, uniform logarithmic Sobolev inequalities along the Ricci flow are derived. Then uniform Sobolev inequalities along the Ricci flow are derived via harmonic analysis of the integral transform of the relevant heat operator. These inequalities are fundamental analytic properties of the Ricci flow. They are also extended to the volume-normalized Ricci flow and the Kahler–Ricci flow.
Hemopoietic colony studies. VI. Increased eosinophil‐containing colonies obtained by antigen pre‐treatment of irradiated mice reconstituted with bone marrow cells

The cellular response to an intraperitoneal injection of antigen (tetanus toxoid) was studied in reconstituted animals in order to determine the mechanism of control of eosinophil granulocytopoiesis. Antigen treatment of the marrow cell donors did not consistently increase the number of spleen and bone marrow colonies in recipient animals or change the percentage of eosinophil or other hemopoietic colony types. Antigen pre-treatment of the irradiated recipients increased the percentage of eosinophil-containing colonies in the spleen and femoral bone marrow without significantly changing the total number of either spleen or marrow colonies. Antigen treatment of both the bone marrow cell donor and recipient produced a further increase in the percentage of eosinophil-containing colonies in the marrow cavity, but not in the spleen. Antigen treatment of the irradiated recipient increased the number of eosinophilic cells (but not the total number of cells) in both the peritoneal cavity and the bone marrow. Antigen treatment of both the marrow donor and recipient produced a further increase in the number of eosinophilic cells in the peritoneal cavity, but not in a single femur. Since antigen treatment of the marrow recipient, or recipient and donor, but not of the marrow donor alone, results in increased eosinophilic cell and colony numbers, the effect of antigen appears to be mediated through some host factor(s), perhaps the eosinophilic hemopoietic inducing microenvironment (HIM), rather than directly on the hemopoietic stem cells.
Squamous cell tumors in mice heterozygous for a null allele of Atp2a2, encoding the sarco(endo)plasmic reticulum Ca2+-ATPase isoform 2 Ca2+ pump.

Mutations in the human ATP2A2gene, encoding sarco(endo)plasmic reticulum Ca2+-ATPase isoform 2 (SERCA2), cause Darier disease, an autosomal dominant skin disease characterized by multiple keratotic papules in the seborrheic regions of the body. Mice with a single functional Atp2a2allele (the mouse homolog of ATP2A2) were shown previously to have reduced levels of SERCA2 in heart and mildly impaired cardiac contractility and relaxation. Here we show that aged heterozygous mutant (Atp2a2 +/−) mice develop squamous cell tumors of the forestomach, esophagus, oral mucosa, tongue, and skin. Squamous cell tumors occurred in 13/14Atp2a2 +/− mice but were not observed in age- and sex-matched wild-type controls. Hyperkeratinized squamous cell papillomas and carcinomas of the upper digestive tract were the most frequent finding among Atp2a2 +/− mice, and many animals had multiple tumors. Western blot analyses showed that SERCA2 protein levels were reduced in skin and other affected tissues of heterozygous mice. The development of squamous cell tumors in agedAtp2a2 +/− mice indicates that SERCA2 haploinsufficiency predisposes murine keratinocytes to neoplasia. These findings provide the first direct demonstration that a perturbation of Ca2+ homeostasis or signaling can serve as a primary initiating event in cancer.
Influence of dynamic strain aging on the dislocation substructure in a uniaxial tension test

In many metals containing alloying elements or impurities a tangled dislocation structure is developed in the temperature range of the yield stress plateau whereas dislocations are distributed uniformly at room temperature after monotonic tensile testing. Above the temperature range of the yield stress plateau the dense cell structure is replaced by a uniform dislocation substructure. In this paper the change in substructure with temperature in alloys (especially in Zircaloy) is explained in terms of dynamic strain aging. In the athermal region of yield stress the dynamic strain aging increases the tendency for a dislocation velocity increase in a low internal stress field and for a dislocation velocity decrease in a high internal stress field. These result in clustering of dislocations at the site of the high internal stress field. However, above the temperature range of the yield stress plateau, dislocations tend to move at the average velocity irrespective of the internal stress field. This tendency results in a homogeneous distribution of dislocations.
On the convergence of the Bremmer series for the Helmholtz equation in 2-D

In this paper we discuss the convergence of the Bremmer series in two dimensions. We show that when the field is separated into left and right travelling waves, the series will diverge if the operator coupling left and right travelling waves is unbounded.
Computers and morphology.

Computers level of society. In the laboratory, virtually all sophisticated instruments have been coupled with computers to acquire, to display, and to analyze data with speed and accuracy. For those interested in correlating structure with function, the computer affords the opportunity to visualize tissues and their cellular and subcellular components in three dimensions (3-D) and to calculate their two-dimensional (2-D) and 3-D parameters. 1 Three-dimensional computer reconstruction of tissues from serial sections represents a major advance in research methodology for the morphologist. The reconstructed tissues can be represented either as wire frame models 2 or as solid objects 3 depending on the software and hardware available to the investigator. The 3-D computer reconstruction represents the epitome of model making because the models can be dissected and put back together at will without their being damaged or destroyed as may occur with models constructed of plasticene, paper, or plastic. In addition,
Fish Utilization of Great Lakes Coastal Wetlands

Correspondence analysis was used to partition fish species associated with the open water of each of the five Great Lakes and nine coastal wetlands for which data were available. Included in the analysis were 113 species in 25 families. Three species complexes were suggested: a Great Lakes taxocene (31 species); a transitional community which utilized open water, nearshore, and wetlands (35 species); and a wetlands taxocene, comprised of 47 species found to be closely associated with coastal wetlands. The wetland species split into two main groups: permanent residents (e.g., brown bullhead Ictalurus nebulosus, mudminnow Umbra lima, longnose gar Lepisosteus osseus) and migratory species. Migratory species included three subgroups: (1) those that spawned in the wetlands and then left (e.g., northern pike Esox lucius, common carp Cyprinus carpio, white sucker Catostomus commersoni, walleye Stizostedion vitreum), (2) those that used the wetlands as a nursery area (e.g., northern pike, gizzard shad Dorosoma cepedianum, spottail shiner Notropis hudsonius), and (3) those that migrated into the wetland from other wetlands or a Great Lake for shelter, spawning sites, or food; as part of the sustaining process of dispersal of young; or as part of wandering behavior (e.g., burbot Lota lota, rainbow smelt Osmerus mordax, rainbow trout Oncorhynchus mykiss). It was found that most remaining coastal wetlands are degraded or altered to some degree, and are dominated by a characteristic silt- and turbidity-tolerant fish fauna (e.g., common carp, gizzard shad, goldfish Carassius auratus, and brown bullhead). Nevertheless, even degraded wetlands still functioned as important fish habitat by exporting large quantities offish, first to avian, piscine, and mammalian food chains through predation, and second to the Great Lakes as young-of-the-year sport and forage fish. The research implies that a wetland must maintain a connection with a Great Lake to promote and enhance efficient fish utilization of the high productivity of marshes; that additional resilience is provided to species which spawn in wetlands since they can produce two cohorts (one in wetlands and one in the Great Lakes), and that fluctuating water levels are important in sustaining habitat diversity and productivity.
On the parallelization of a global climate-chemistry modeling system

Abstract Coupled climate-chemistry simulations are computationally intensive owing to the spatial and temporal scope of the problem. In global chemistry models, the time integrations encountered in the chemistry and aerosol modules usually comprise the major CPU consumption. Parallelization of these segments of the code can contribute to multifold CPU speed-ups with minimal modification of the original serial code. This technical note presents a single program-multiple data (SPMD) strategy applied to the time-split chemistry modules of a coupled climate – global tropospheric chemistry model. Latitudinal domain decomposition is adopted along with a dynamic load-balancing technique that uses the previous time-step’s load/latitude estimates for distributing the latitude bands amongst the processors. The coupled model is manually parallelized using the Message Passing Interface standard (MPI) on a distributed memory platform (IBM-SP2). Load-balancing efficiencies and the associated MPI overheads are discussed. Overall speed-ups and efficiencies are also calculated for a series of runs employing up to eight processors.
β‐Endorphin: synthesis and properties of human β‐endorphin‐(1–28) and its analogs

Three analogs of human beta-endorphin (beta h-EP) were synthesized by the solid-phage method: beta h-EP-(1--28) (I). [Gln8]-beta h-EP-(1--28) (II), and [D-Ala2, Gln8]-beta h-EP-(1--28) (III). Radioreceptor binding assay with use of tritiated beta h-EP as primary ligand gave relative potencies as follows: beta h-EP, 100; I, 85; II, 380; III, 146. Relative potencies in an analgesic assay were: beta h-EP; 100; I, 18; II, 36; III, 13.
Electrophysiologic Study of the Left Ventricle: Indications and Safety

Eighty patients (69 with documented or suspected recurrent ventricular tachycardia or fibrillation, ten with left bundle-branch block, and one with the Wolff-Parkinson-White syndrome) underwent both right ventricular and left ventricular programmed electrical stimulation, including ventricular pacing and the introduction of one or two ventricular extrastimuli or electrode catheter mapping of the left ventricle (or both). Left ventricular catheters were introduced precutaneously via the femoral artery (of 61 patients, one required secondary repair) or via brachial arteriotomy (of 19 patients, two required secondary repair). All patients received an intravenously administered bolus of heparin (5,000 units) following the insertion of the left ventricular catheter and then 1,000 units/hr after the first hour of study. No patients had cerebrovascular, systemic thromboembolic, or cardiac sequelae. In four (12 percent) of 34 patients with inductible ventricular tachycardia, programmed electrical stimulation of the left ventricle was required for initiation. Extensive left ventricular endocardial mapping was performed in 45 patients. Our experience suggests that (1) electrophysiologic study of the left ventricle can be performed safely, (2) programmed electrical stimulation of the left ventricle is indicated when a suspected ventricular tachyarrhythmia cannot be induced from the right ventricle, and (3) endocardial mapping of the left ventricle is indicated when surgery is being considered to abolish recurrent sustained ventricular tachycardia.
In-Vitro Wall Shear Stress Measurements for Microfluid Flows by Using Second-Order SPE Micro-PIV

Conventional single pixel evaluation (SPE) significantly improves the spatial resolution of PIV measurements to the physical limit of a CCD camera based on the forward difference interrogation (FDI). This paper further enhances the computational algorithm to second-order accuracy by simply modifying the numerical scheme with the central difference interrogation (CDI). The proposed central difference scheme basically superposes the forward-time and the backward-time correlation domains, thus resulting in reduced bias error as well as rapid background noise elimination. An assessment of the CDI SPE algorithm regarding the measurement errors was achieved via numerous synthetic images subject to a four-roll mill flow. In addition, preliminary wall shear stress (WSS) measurements regarding different algorithms are also evaluated with an analytical turbulent boundary flow. CDI scheme showed a 0.32% error deviated from the analytical solution and improved the same error in FFT-based correlation correlation (FFT-CC) by 32.35%. To demonstrate the performance in practice, in-vitro measurements were implemented in a serpentine microchannel made of polydimethyl siloxane (PDMS) for both CDI SPE and spatial cross-correlation. A series of steady-state flow images at five specified regions of interest were acquired using micro-PIV system. Final comparisons of the WSS regarding the Pearson correlation coefficient, R2 , between the numerical schemes and the simulations showed that an overall result was improved by CDI SPE due to the fine resolution and the enhanced accuracy.Copyright © 2007 by ASME
Acid-catalyzed hydrolysis of lignin β-O-4 linkages in ionic liquid solvents: a computational mechanistic study

This work presents a computational mechanistic study of the acid-catalyzed hydrolysis of lignin β-O-4 linkages in ionic liquid solvents. Model compound 2-hydroyxyethyl phenyl ether undergoes dehydration to vinyl phenyl ether followed by hydrolysis to phenol and “Hibbert's ketones”. Larger model compound α-hydroxy-phenethyl phenyl ether illustrates an E1 dehydration mechanism involving resonance-stabilized carbocations. Continuum models for ionic liquid solvents indicate that solvation can significantly affect the reaction rates. The tested continuum ionic liquid solvents give similar results, and differ significantly from continuum organic solvents with comparable dielectric constants. The acidic ionic liquid cation 1-H-3-methylimidazolium has lower predicted catalytic activity than hydronium or HCl, consistent with the former's relatively small acid dissociation constant. Calculations with dispersion-corrected density functionals give similar behavior. Calculations on Lewis acidic metal chlorides used experimentally for lignin hydrolysis suggest that the metal chloride may participate in the initial dehydration. These results provide a baseline for future studies of improved hydrolysis catalysts.
Are Cell Phones or Radio-Frequency Electromagnetic Fields Possibly Carcinogenic to Humans? [Telecommunications Health and Safety]

Notwithstanding the recent classification of radio-frequency electromagnetic fields, including those employed by cellular mobile telephones, as possibly carcinogenic to humans, the question of whether there could be some cancer risk associated with use of cell phones remain confused and ever more controversial.
On flow in Northwestern Gulf of Alaska, May 1972

Southwestward volume transport (referred to 1,500 db) out of the Gulf of Alaska seaward of the continental shelf in May 1972 was 12.5 Sv, and nearly 3/4 of this flow occurred within 50 km of the shelf edge. Mean geostrophic velocities of about 50 cm s−1 occurred in a band 20 km wide, which extended 500 km along the shelf edge; a maximum velocity of 98 cm s−1 (nearly 2 knots) was obtained. Bottom flow along the inshore part of the shelf as determined by seabed drifters was generally onshore at 0.5 cm s−1. Evidence is presented of a large cyclonic gyre on the shelf encompassing the Portlock and Albatross Banks, perturbations in surface flow along the shelf edge, and relations between coastal tidal heights and fluctuations in geopotential topography at the shelf edge.
Scalable Algorithms for Distributed-Memory Adaptive Mesh Refinement

This paper presents scalable algorithms and data structures for adaptive mesh refinement computations. We describe a novel mesh restructuring algorithm for adaptive mesh refinement computations that uses a constant number of collectives regardless of the refinement depth. To further increase scalability, we describe a localized hierarchical coordinate-based block indexing scheme in contrast to traditional linear numbering schemes, which incur unnecessary synchronization. In contrast to the existing approaches which take O(P) time and storage per process, our approach takes only constant time and has very small memory footprint. With these optimizations as well as an efficient mapping scheme, our algorithm is scalable and suitable for large, highly-refined meshes. We present strong-scaling experiments up to 2k ranks on Cray XK6, and 32k ranks on IBM Blue Gene/Q.
Three-Dimensional Molecular Dynamics Analysis of Atomic-Scale Indentation

The complete atomic-scale indentation cycle is analyzed using molecular dynamics simulations. A hysteresis is observed in the instantaneous normalforce versus surface separation distance curve obtained with an atom or a rigid tip indenting and, subsequently, retracting from a dynamic face-centered-cubic substrate consisting of argon or copper. The generation of irreversible deformation in a Lennard-Jones solid is revealed in light of simulation results for indentation by a single atom. The direction of irreversible deformation is shown to coincide with that of macroscopic plastic flow. The compressive yield strength decreases with increasing substrate temperature and decreasing indentation speed. The phenomena of tip wetting by substrate atoms and connective neck formation, elongation, and rupture at the tip/substrate interface are elucidated by simulation results for the unloading process. It is shown that energy dissipation decreases as the substrate temperature increases and the energy consumed by irreversible deformation is always greater than that due to heating.
The fluorescence of tyrosine in alkaline solution

Abstract 1. 1. Contrary to previous reports in the literature, tyrosine in strongly alkaline solution (0.12 N NaOH in our experiments) was found to have a measurable fluorescence, and determinations of the relative quantum yield of this species are presented. 2. 2. It was found that tyrosine and two proteins exhibiting tyrosine fluorescence, insulin and RNAase, show a shift in the peak of their fluorescence spectra from 315 mμ in neutral H2O to 345 mμ in 0.12 N NaOH. 3. 3. Under neutral conditions the quantum yield of tyrosine incorporated in a protein is diminished when compared with that of free tyrosine in solution. This is not the case in 0.12 N NaOH, suggesting the presence under neutral conditions of a “structural quenching effect” not present under alkaline conditions.
Oligomeric State of a Pannexin Channel

Pannexins are a recently-discovered family of integral membrane proteins in vertebrates that form non-selective homomeric or heteromeric pores in the plasma membrane. These channels seem important in ATP signaling in the central nervous system and the immune response, as well as in ischemic and apoptotic cell death, yet their mechanism remains unknown. One important question is how pannexin subunits come together to form the large channel. While the membrane topology suggests that pannexins resemble hexameric connexins, there has been no bona fide evidence supporting such structural analogy between the two distinct large-pore channels with no sequence similarity. To address how many subunits constitute pannexin channels, we first identified a pannexin orthologue that forms a monodisperse oligomer upon solubilization in a relatively mild detergent, such as dodecyl maltoside, using the fluorescence detection size exclusion chromatography strategy. Interestingly, we discovered that most of the 28 arbitrarily collected pannexin channels from multiple organisms tend to aggregate or dissociate into monomers upon solubilization in detergents, making the selected stable pannexin channel an ideal paradigm for biochemical characterization. We subsequently purified this stable pannexin channel using a baculovirus-insect cell expression system. In this poster, we present the oligomeric state of the pannexin channel measured through multi-angle light scattering and crosslinking experiments.
Enhanced functions of osteoblasts on nanophase ceramics

Select functions of osteoblasts (bone-forming cells) on nanophase (materials with grain sizes less than 100 nm) alumina, titania, and hydroxyapatite (HA) were investigated using in vitro cellular models. Compared to conventional ceramics, surface occupancy of osteoblast colonies was significantly less on all nanophase ceramics tested in the present study after 4 and 6 days of culture. Osteoblast proliferation was significantly greater on nanophase alumina, titania, and HA than on conventional formulations of the same ceramic after 3 and 5 days. More importantly, compared to conventional ceramics, synthesis of alkaline phosphatase and deposition of calcium-containing mineral was significantly greater by osteoblasts cultured on nanophase than on conventional ceramics after 21 and 28 days. The results of the present study provided the first evidence of enhanced long-term (on the order of days to weeks) functions of osteoblasts cultured on nanophase ceramics; in this manner, nanophase ceramics clearly represent a unique and promising class of orthopaedic/dental implant formulations with improved osseointegrative properties.
Numerical Calculation of Heat Transfer Coefficient of Liquid Flow With NPCM in Microchannels

A continuum model is applied to the numerical simulation of the laminar hydrodynamic and heat-transfer characteristics of suspension with nano phase change material (NPCM) particles in a microchannel. The analytical/numerical formulation based on CFD modeling technique, and the computer code is developed. Local wall-to-suspension heat transfer coefficients are calculated by the simultaneous solution of the conservation of mass, momentum and thermal energy equations. By providing detailed information on the local behavior of the wall-to-suspension heat transfer coefficients, preliminary calculations expose that there exists a particle-depleted layer next to the wall under the laminar flow condition. It plays an important role on the heat transfer between the suspension and the wall under the laminar flow condition. The main contribution of NPCM particles is the increase in the thermal capacity under the laminar flow condition. The qualitative comparison with the experimental observations and measurements on the flow and heat transfer of microencapsulated PCM slurry in circular duct indicates that the preliminary results are reasonable. It interprets the observation in the literature where heat transfer between the suspension and the wall is weaker than that between the pure fluid and the wall for laminar flow conditions.Copyright © 2003 by ASME
The Fredholm Index for Elements of Toeplitz-Composition C * -Algebras

We analyze the essential sectrum and index theory of elements of Toeplitz-composition C*-algebras (algebras generated by the Toeplitz algebra and a single linear-fractional composition operator, acting on the Hardy space of the unit disk). For automorphic composition operators we show that the quotient of the Toeplitz-composition algebra by the compacts is isomorphic to the crossed product C*-algebra for the action of the symbol on the boundary circle. Using this result we obtain sufficient conditions for polynomial elements of the algebra to be Fredholm, by analyzing the spectrum of elements of the crossed product. We also obtain an integral formula for the Fredholm index in terms of a generalized Chern character. Finally we prove an index formula for the case of the non-parabolic, non-automorphic linear fractional maps studied by Kriete, MacCluer and Moorhouse.
Residential Proximity to Methyl Bromide Use and Birth Outcomes in an Agricultural Population in California

Background: Methyl bromide, a fungicide often used in strawberry cultivation, is of concern for residents who live near agricultural applications because of its toxicity and potential for drift. Little is known about the effects of methyl bromide exposure during pregnancy. Objective: We investigated the relationship between residential proximity to methyl bromide use and birth outcomes. Methods: Participants were from the CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas) study (n = 442), a longitudinal cohort study examining the health effects of environmental exposures on pregnant women and their children in an agricultural community in northern California. Using data from the California Pesticide Use Reporting system, we employed a geographic information system to estimate the amount of methyl bromide applied within 5 km of a woman’s residence during pregnancy. Multiple linear regression models were used to estimate associations between trimester-specific proximity to use and birth weight, length, head circumference, and gestational age. Results: High methyl bromide use (vs. no use) within 5 km of the home during the second trimester was negatively associated with birth weight (β = –113.1 g; CI: –218.1, –8.1), birth length (β = –0.85 cm; CI: –1.44, –0.27), and head circumference (β = –0.33 cm; CI: –0.67, 0.01). These outcomes were also associated with moderate methyl bromide use during the second trimester. Negative associations with fetal growth parameters were stronger when larger (5 km and 8 km) versus smaller (1 km and 3 km) buffer zones were used to estimate exposure. Conclusions: Residential proximity to methyl bromide use during the second trimester was associated with markers of restricted fetal growth in our study.
Bent crystal analyzer without grooves for inelastic scattering -- first experimental results

A new design of a bent crystal analyzer for high energy resolution inelastic X-ray scattering has been recently proposed. It has been theoretically predicted that an analyzer with reflecting planes at a certain angle with respect to a crystal surface, bent with two different radii of curvature, will have the same energy resolution as a perfect crystal. The first experimental measurement obtained at the Advanced Photon Source of a bandwidth of such an analyzer is presented. The overall energy resolution of the analyzer and monochromator observed with a narrow beam is equal to 16.4 meV (FWHM) at 13.84 KeV.