cssi/SciSciGPT-SciSciNet huggingface dataset:
Research on the Line Style of Shaft Housing Pairs of Progressing Cavity Pump

The progressing cavity pump (PCP) has a good usage foreground on the seabed oilfield. The most important invalidation reason of PCP is the rubber shaft housing’s abrasion. This article introduced the hypocycloid single-screw hydraulic machinery’s primary line style and isometric profiles equations, analyzed the contact status between the primary line styles of rotor and stator, and explained why the isometric curves have been used as the cross section of PCP. Defined the concept of turning point, deduced the turning point and midpoint’s contact angle formula of the hypocycloid singlescrew hydraulic machinery, then compared the contact angles of three models as i = 1/2, 2/3, 3/4. Concluded that if shorten the contact time of rotor with stator’s turning point, the abrasion of stator’s turning point will be relieved, the life of the hypocycloid single-screw hydraulic machinery will be longer.Copyright © 2010 by ASME
Subgradient Methods for Saddle-Point Problems

We study subgradient methods for computing the saddle points of a convex-concave function. Our motivation comes from networking applications where dual and primal-dual subgradient methods have attracted much attention in the design of decentralized network protocols. We first present a subgradient algorithm for generating approximate saddle points and provide per-iteration convergence rate estimates on the constructed solutions. We then focus on Lagrangian duality, where we consider a convex primal optimization problem and its Lagrangian dual problem, and generate approximate primal-dual optimal solutions as approximate saddle points of the Lagrangian function. We present a variation of our subgradient method under the Slater constraint qualification and provide stronger estimates on the convergence rate of the generated primal sequences. In particular, we provide bounds on the amount of feasibility violation and on the primal objective function values at the approximate solutions. Our algorithm is particularly well-suited for problems where the subgradient of the dual function cannot be evaluated easily (equivalently, the minimum of the Lagrangian function at a dual solution cannot be computed efficiently), thus impeding the use of dual subgradient methods.
Electronic Government and Online Engagement: Citizen Interaction with Government via Web Portals

This exploratory study examines civic engagement with e-government via Web sites. It provides an analytical framework that integrates both the supply and the demand sides of citizen interaction with e-government. In modeling three dimensions of online civic engagement (government information access, service transactions, and contributing to government policy-making processes), the study framework incorporates a number of variables, including political activism, civic involvement, perceived benefits and difficulties, information channels, and demographic characteristics. Based on a national sample of Internet users, the study highlights the importance of the supply side (availability of e-government) for promoting civic engagement. Furthermore, political activism is found to be related positively to accessing government policy information and contributing to policy-making processes. The study results also confirm the significant impact of perceived benefits in fostering online civic engagement. Future research can benefit from this study by utilizing a more comprehensive model, treating various dimensions of online engagement separately, and conducting an in-depth analysis of the elements of perceived benefits.
"Making Sense" in a Collaborative Teacher Education Prografll: Lessons from Project PART Students:

We studied the first cohort to graduate from a collaborative elementary/special education teacher education program at the University of Florida. The program was federally funded, and the curriculum was created by requiring elementary majors to take additional special education courses. However, because we exercised no control over course instructors, the content they taught and the perspectives they espoused were not necessarily consistent with ours. We were concerned that the program lacked thematic integrity and that students might flounder in the absence of a consistent message from instructors. To address these concerns, we observed students in field placements, interviewed them and their cooperating teachers, and reviewed documents. Our interpretation of these data suggests that PART students were little troubled by the diversity of instructor perspectives; to the contrary, because exposure to diverse points of view broadened their repertoires, they regarded it as a strength of the program. They als...
Norms of powers of the Volterra operator

The norms of them-th powers of the Volterra operatorV onL2[0, 1] are computed form=1,...,10. These numbers suggest that the sequencem!‖V‖ is bounded above and below, which is shown, and that this sequence converges to 1/2, which is conjectured.
Wikipedia in Action: Ontological Knowledge in Text Categorization

We present a new, ontology-based approach to the automatic text categorization. An important and novel aspect of this approach is that our categorization method does not require a training set, which is in contrast to the traditional statistical and probabilistic methods. In the presented method, the ontology, including the domain concepts organized into hierarchies of categories and interconnected by relationships, as well as instances and connections among them, effectively becomes the classifier. Our method focuses on (i) converting a text document into a thematic graph of entities occurring in the document, (ii) ontological classification of the entities in the graph, and (iii) determining the overall categorization of the thematic graph, and as a result, the document itself. In the presented experiments, we used an RDF ontology constructed from the full English version of Wikipedia. Our experiments, conducted on corpora of Reuters news articles, showed that our training-less categorization method achieved a very good overall accuracy.
Gordius: a data parallel algorithm for spatial data conversion

Abstract A data parallel algorithm is presented for spatial data (raster-to-vector) conversion. It operates on pure two-dimensional raster images and derives a fully topological vector data set, where polygons are defined by homogeneity criteria. The algorithm is implemented in data parallel C, and makes extensive use of scan functions that combine communication and computation along grid axes. Code segments listing each step in building a hierarchy of points, lines, and polygons are listed. Performance evaluations on a Connection Machine-2 reveal that run-time is not sensitive to the number of polygons in the image, and increases sublinearly with grid size.
Charts of normal body measurements and revised width-weight tables in graphic form

Tables and graphs showing means and standard deviations of head, face, and bodymeasurements for 6,000 girls and 6,000 boys, aged one to 15 years, have been prepared to be used as a normal backdrop to help assess growth problems. Comparing physical measurements of a given child with those of a large number of normal, healthy children, offers a gauge of the child's normality and documents clincal judgment. A graphic form is often better understood by parents than a complicated explantation. The width-weight table (Chart 10 for boys) in graphic form predicts appropriate weight for age and sex at each inch of height modified by bi-iliac and lateral thoracic diameters.
Ultraviolet spectroscopic study of ferric hydroxide complexation

Ultraviolet absorbance spectra of ferric ions in 0.68m NaClO4 were studied as a function of pH at 4.0, 14.9, and 25.0°C. The results provided an evaluation of the stability constant for the formation of FeOH2+ which is *β1=[FeOH+][H+]/[Fe3+]. The enthalpy change for the reaction Fe3++H2O⇌ FeOH2++H+ was calculated as 10.0±0.3 kcal-mole−1. Increasing temperature was also found to promote the reaction Fe3++2H2O⇌ Fe(OH)2++2H+. Our results were combined with the results of other to produce an expression describing the first hydrolysis equilibrium at ionic strengths between 0 and 3m and temperatures between 4.0 and 45.0°C at 1 atm total pressure. At 25°C and 0.68m the ionic strength *β1=1.90×10-3
A One-Dimensional Model for Dispersive Wave Turbulence

A family of one-dimensional nonlinear dispersive wave equations is introduced as a model for assessing the validity of weak turbulence theory for random waves in an unambiguous and transparent fashion. These models have an explicitly solvable weak turbulence theory which is developed here, with Kolmogorov-type wave number spectra exhibiting interesting dependence on parameters in the equations. These predictions of weak turbulence theory are compared with numerical solutions with damping and driving that exhibit a statistical inertial scaling range over as much as two decades in wave number.
Continuous culture as a tool for investigating the growth physiology of heterotrophic hyperthermophiles and extreme thermoacidophiles

Although there is great scientific and technological interest in examining the physiology and bioenergetics of micro-organisms from extreme environments, difficulties encountered in their cultivation and lack of genetic systems hampers the investigation of these issues. As such, we have adapted methods for continuous cultivation of mesophilic organisms to extremes of temperature and pH to study extremophiles. Since the risk for contamination of extrem-ophilic continuous cultures is relatively small, long-term, steady state experiments investigating physiological response to culture perturbations are possible. Experiments along these lines have provided insights into the significance of specific enzymes in the metabolism of particular substrates, in addition to providing a better understanding of stress response and unusual physiological characteristics of hyperthermophilic and extremely thermoacidophilic micro-organisms. Several examples are provided here, including the thermal stress response of Metallosphaera sedula (T opt 74 °C) growing at pH 2.0, and the response of the heterotrophic hyperthermophiles Pyrococcus furiosus (T opt 98°C), Thermococcus litoralis (T opt 88 °C) and T. maritima (T opt 80 °C) to changes in growth medium. Also discussed will be how the same experimental systems have been used to study exopolysaccharide production and biofilm formation by hyperthermophilic heterotrophs and facilitated the estimation of bioenergetic parameters for these organisms under a variety of growth conditions. Continuous culture, used in conjunction with genome sequence information, two-dimensional gel electrophoresis and differential gene expression, can provide important insights into the metabolism of high temperature extremophiles.
Kidney dysfunction in the recipients of liver transplants

1. Pretransplant kidney function is an important predictor of posttransplant kidney function. 2. Chronic kidney disease is present in 20% of liver transplant recipients by 5 years. 3. Kidney function is impacted by pretransplant management of the consequences of the hepatorenal syndrome. 4. The use of calcineurin inhibitor (CNI)-based immunosuppression is an important factor in the development of chronic kidney disease, and the use of mycophenolic acid- or sirolimus-based immunosuppression with reduced-dose CNI may be of benefit.
Development and application of earth system models

The global environment is a complex and dynamic system. Earth system modeling is needed to help understand changes in interacting subsystems, elucidate the influence of human activities, and explore possible future changes. Integrated assessment of environment and human development is arguably the most difficult and most important “systems” problem faced. To illustrate this approach, we present results from the integrated global system model (IGSM), which consists of coupled submodels addressing economic development, atmospheric chemistry, climate dynamics, and ecosystem processes. An uncertainty analysis implies that without mitigation policies, the global average surface temperature may rise between 3.5 °C and 7.4 °C from 1981–2000 to 2091–2100 (90% confidence limits). Polar temperatures, absent policy, are projected to rise from about 6.4 °C to 14 °C (90% confidence limits). Similar analysis of four increasingly stringent climate mitigation policy cases involving stabilization of greenhouse gases at various levels indicates that the greatest effect of these policies is to lower the probability of extreme changes. The IGSM is also used to elucidate potential unintended environmental consequences of renewable energy at large scales. There are significant reasons for attention to climate adaptation in addition to climate mitigation that earth system models can help inform. These models can also be applied to evaluate whether “climate engineering” is a viable option or a dangerous diversion. We must prepare young people to address this issue: The problem of preserving a habitable planet will engage present and future generations. Scientists must improve communication if research is to inform the public and policy makers better.
Berezin Quantization and K-Homology

The E-theory defined by Connes and Higson provides a realization of K-homology, the generalized homology theory dual to K-theory, based on the notion of asymptotic homomorphisms. With this realization it becomes possible to associate a K-homology element to a quantization scheme. In this article we associate an asymptotic homomorphism and K-homology element to the Berezin quantization of a bounded symmetric domain. Further, we identify this element with the element of K-homology defined by the Dolbeault operator of the domain.
Piezotronic and Piezophototronic Effects

Owing to the polarization of ions in a crystal that has noncentral symmetry, a piezoelectric potential (piezopotential) is created in the material by applying a stress. The creation of piezopotential together with the presence of Schottky contacts are the fundamental physics responsible for a few important nanotechnologies. The nanogenerator is based on the piezopotential-driven transient flow of electrons in the external load. On the basis of nanomaterials in the wurtzite semiconductors, such as ZnO and GaN, electronics fabricated by using a piezopotential as a gate voltage are called piezotronics, with applications in strain/force/pressure-triggered/controlled electronic devices, sensors, and logic gates. The piezophototronic effect is a result of three-way coupling among piezoelectricity, photonic excitation, and semiconductor transport, which allows tuning and controlling of electro-optical processes by a strain-induced piezopotential.
Mosquito repellents and superwarfarin rodenticides--are they really toxic in children?

PURPOSE OF REVIEW: In many United States households, there are many substances used to control the exposure of our children to mosquitoes, mice and rats. This review provides information on common mosquito repellents and rodenticides used in households and discusses their toxicity, in order to help pediatricians better advise their patients of their proper use. RECENT FINDINGS: A recent study has demonstrated that many continue to have practices of applying DEET (N,N-diethyl-3-methylbenzamide) based repellents that may lead to undesirable effects. Picaridin and oil of lemon eucalyptus are two products that have recently been shown to have an efficacy similar to that of DEET-based repellents. Studies within the last five years show that most unintentional superwarfarin ingestions can be managed at home with close outpatient follow-up. There does not appear to be a benefit of prophylactic vitamin K or gastrointestinal decontamination in patients with relatively small ingestions of superwarfarins. SUMMARY: With education and correct usage, mosquito repellents and the superwarfarin rodenticides can help protect children from significant vector-borne diseases. Not all exposures lead to significant morbidity or mortality. With recognition of the current literature, most of these exposures can be managed safely at home or as an outpatient, ultimately saving healthcare costs. Language: en
Growth of genome screening needs debate

There could be unexpected consequences if greater understanding of disease genetics gives parents more choice in what they pass to their children, says David B. Goldstein.
A method for the precise switching of speech

A simple procedure by which a speech signal may be switched on or off (or from one ear to the other) at a precise instant of time is described. The speech sample is first recorded on a magnetic tape loop. A reference pulse is then recorded preceding the speech signal. This reference pulse triggers an adjustable time delay which in tum operates an electronic switch at an appropriate time.
Contamination simulation facility with in situ infrared analysis capability

A new volatile condensable materials (VCM) facility has been constructed. The facility features a unique in situ Fourier transform infrared spectrophotometric system in addition to a quartz crystal microbalance and quadrupole mass spectrometer. Contaminants can be collected and subjected to infrared spectroscopy at the collection temperature, circumventing problems associated with ex situ infrared measurements. Preliminary results indicate that VCM, with deposition thicknesses less than 200 A, can be identified.
Combination chemotherapy with mitomycin C, methotrexate, cisplatin, and vinblastine in the treatment of non‐small cell lung cancer

The combination of mitomycin C, methotrexate, cisplatin, and vinblastine was administered to 45 patients with unresectable non-small cell lung cancer. Thirty-nine patients satisfied criteria for assessment of response to chemotherapy. All patients had a performance status of greater than 50%, had evaluable disease, and had not received previous chemotherapy. The overall response rate was 54% with responses seen in 12 of 19 squamous cell, 8 of 16 adenocarcinoma, and 1 of 4 undifferentiated large cell lung cancer patients. Median survival was increased by 3 months in those patients with an objective response to chemotherapy. Drug-associated toxicity was rare, but apparent mitomycin C-related pulmonary fibrosis was observed in two patients. This four-drug combination was shown to be an active regimen in the treatment of non-small cell bronchogenic carcinoma.
Applications of Hellinger's integrals in detection theory

Consider the stochastic process x(t) = a(t) + n(t), (- 02 <t < co), (1) where n(t) is a complex-valued weakly stationary Gaussian process which represents the noise, and a(t) is a complex-valued function representing the signal. Let the spectral distribution function F(.) of n(t) be absolutely continuous (a.c.) with respect to (w.r.t.) the Lebesgue (Leb.) measure. Let a(.) be square-integrable w.r.t. Leb. measure and d(a) be its Fourier transform. W. L. Root in [l] and [2], E. J. Kelly and others in [3] have shown that if
BARRIERS TO PRENATAL CARE IN A MULTIETHNIC, URBAN SAMPLE

The barriers that prevent women from obtaining prenatal care were studied in a multiethnic, primarily indigent urban population. Two thousand nine hundred eighty-seven women were delivered at the University of Miami/Jackson Memorial Medical Center from January 15 to April 10, 1988. Of these women, 227 (7.6%) did not access any prenatal care. These women formed the study group. The results indicated that the main barriers were systematic (35.5%), patient-related (35.5%), and financial (29%). Ethnic group, marital status, and education influenced access to prenatal care, whereas age did not appear to do so. Although low birth weight rates were higher in the study group, it was apparent that cultural behavior influenced birth weight, whether or not prenatal care was obtained.
Monochromator-induced glitches in EXAFS data I. Test of the model for linearly tapered samples

Abstract When EXAFS samples are slightly nonuniform in thickness, spikes, referred to as “glitches”, are observed in the data. Such features are intrinsic to data collected using crystal monochromators. We have recently developed a model to show why such features, persist in ratioed data. Here we test the predictions for linearly tapered samples. Our results suggest that the glitch mplitude can be significantly reduced by taking a second spectrum with the sample inverted, and then averaging the two spectra.
On the Structure and Properties of Differentially Rotating, Main-Sequence Stars in the 1-2 M☉ Range

We present models for chemically homogeneous, differentially rotating, main-sequence stars with masses in the range 1-2 M☉. The models were constructed using a code based on a reformulation of the self-consistent field method of computing the equilibrium stellar structure for a specified conservative internal rotation law. Relative to nonrotating stars of the same mass, these models all have reduced luminosities and effective temperatures, and flattened photospheric shapes (i.e., decreased polar radii) with equatorial radii that can be larger or smaller, depending on the degree of differential rotation. For a fixed ratio of the axial rotation rate to the surface equatorial rotation rate, increasingly rapid rotation generally deepens convective envelopes, shrinks convective cores, and can lead to the presence of a convective core (envelope) in a 1 (2) M☉ model, a feature that is absent in a nonrotating star of the same mass. The positions of differentially rotating models for a given mass in the H-R diagram can be shifted in such a way as to approximate the nonrotating ZAMS for lower mass stars. Implications of these results include (1) possible ambiguities arising from similarities between the properties of rotating and nonrotating models of different masses, (2) a reduced radiative luminosity for a young, rapidly rotating Sun, (3) modified rates of lithium destruction by nuclear processes in the layers beneath an outer convective envelope, and (4) the excitation of solar-like oscillations and the operation of a solar-like hydromagnetic dynamo in some 1.5-2 M☉ stars.
Catalysis of the Oligomerization of O-Phospho-Serine, Aspartic Acid, or Glutamic Acid by Cationic Micelles

Treatment of relatively concentrated aqueous solutions of O-phospho-serine (50 mM), aspartic acid (100 mM) or glutamic acid (100 mM) with carbonyldiimidazole leads to the formation of an activated intermediate that oligomerizes efficiently. When the concentration of amino acid is reduced tenfold, few long oligomers can be detected. Positively-charged cetyltrimethyl ammonium bromide micelles concentrate the negatively-charged activated intermediates of the amino acids at their surfaces and catalyze efficient oligomerization even from dilute solutions.
The conserved R166 residue of ALDH5A (succinic semialdehyde dehydrogenase) has multiple functional roles.

Abstract ALDH5 (aka succinic semialdehyde dehydrogenase) is a NAD + -dependent aldehyde dehydrogenase crucial for the proper removal of the GABA metabolite succinic semialdehyde (SSA). All known ALDH5 family members contain the conserved amino acid sequence “MITRK”. Our studies of rat ALDH5A indicate that residue R166 in this sequence may play a role in the substrate specificity of ALDH5A for the γ-carboxylated succinic semialdehyde versus other aliphatic and aromatic aldehydes including acetaldehyde and benzaldehyde. We tested the hypothesis that the R166 residue regulates aldehyde specificity by utilizing rat ALDH5A wild-type (R166wt) and R166K, R166H, R166A, and R166E mutants. The V MAX using SSA fell whereas the K M for SSA increased for all mutants analyzed yielding k cat / K M (s −1 /μM) ratios of 52.3 (R166wt), 5.5 (R166K), 0.01 (R166H), 0.008 (R166E), and 0.004 (R166A). Utilization of acetaldehyde by the R166H mutant was similar to R166wt with k cat / K M 's of 0.003 and 0.002, respectively. Almost no activity towards acetaldehyde was noted for the R166E and R166A mutants. Unexpectedly, the K M for NAD + changed: 21 μM (R166wt), 81 μM (R166K), 63 μM (R166H), 35 μM (R166E) and 44 μM (R166A). As release of NADH can be a rate-limiting step for ALDH activity, NADH binding was evaluated for R166wt and R166H enzymes. The K D of NADH for R166H (0.9 μM) was 11-fold less than that of ALDH5A wt (10.3 μM) and possibly explains the increase in the K M for NAD + . Furthermore, data using R166K and R166H mutants demonstrate that inhibition of enzyme activity by low pH is regulated in part by the R166 residue. Our data indicate that the R166 residue of ALDH5A regulates multiple enzymatic functions.
Regulated high-level expression of the Herpes simplex type I thymidine kinase gene in Escherichia coli

Abstract A plasmid-borne Herpes simplex virus type 1 (HSV-1) thymidine kinase (TK) gene ( tk ) was expressed in Escherichia coli by inserting a 203-bp lac L8/UV5 promoter-operator segment, in frame, 53 bp 5' to the native tk translational start codon. The hybrid gene created by this fusion encodes a polypeptide which has 25 additional amino acids on the amino terminus of the HSV-1 TK protein and phenotypically complements a tdk − mutation of E. coli . This fusion polypeptide has been characterized by maxicell, immunoprecipitation, and native gel techniques, and its activity is inhibited by anti-HSV-1 antibody. In a tk expressor strain containing a F' lacI q (which overproduces the lactose repressor), the isopropyl-β- d -thiogalactoside (IPTG) causes > 1000-fold coordinate induction of the plasmid-encoded TK and chromosomal β-galactosidase activities. Pulse-chase induction demonstrates the fused TK polypeptide to be as stable as β-galactosidase. HSV-1 rife-specific RNA isolated from this bacterial strain has a short half-life characteristic of bacterial messages.
Contingency management in a municipally-administered antabuse program for alcoholics☆

Abstract A municipally-administered Antabuse program involving contingency management for chronic alcoholics is described. Chronic “revolving door” alcoholics were given the option of the usual jail sentence or a 1 yr probation with continued Antabuse treatment. Participants in the program were required to visit the probation office twice a week to take their Antabuse; failure to appear resulted in immediate reinstatement of the suspended jail sentence. The Antabuse program in conjunction with contingency control was effective in reducing the rate of arrests.
The role of social reinforcement in maintaining an obsessive-compulsive neurosis

Abstract A patient with obsessive fears of being bitten by cats or dogs was treated with thought-stopping. While relatively successful, the treatment did not completely eliminate the obsession. After an analysis of the reinforcement contingencies for the patient's behavior, a contract limiting the patient's husband's delivery of social reinforcers was instituted. This contract successfully eliminated the obsession.
The watershed protection approach

The Water Protection Approach (WPA) by USEPA is outlined. The historical development of the approach is of an old date, starting since 1980. Definition of the approach and experience to date is summarized. It is not a new programm, but a new way of thinking about how environmental programs have to be managed.
Methodological variables in verbal discrimination learning

In a factorial experiment the study-test method of presenting VD pairs was found to be superior to the standard anticipation procedure. Instructions to guess on the first trial resulted in more errors in the anticipation condition but not in the recall condition, as compared to instructions merely to observe the pairs on the first trial. Serial vs random ordering of the pairs resulted in no significant differences in performance, but females consistently made fewer errors than males in all conditions.
Cultural Approaches to Parenting

SYNOPSIS This article first introduces some main ideas behind culture and parenting and next addresses philosophical rationales and methodological considerations central to cultural approaches to parenting, including a brief account of a cross-cultural study of parenting. It then focuses on universals, specifics, and distinctions between form (behavior) and function (meaning) in parenting as embedded in culture. The article concludes by pointing to social policy implications as well as future directions prompted by a cultural approach to parenting. This article not subject to US copyright law.
Facilitating application of electrical safety best practices to “other” workers

The premise of this paper is that a significant portion of the workforce has been unintentionally overlooked in some efforts to reduce electrical injuries and fatalities in North America. This paper discusses the limitations, application, and potential impact of North American standards providing measures for electrical injury and fatality prevention and protection to workers. In particular, it discusses workers who may not be considered the primary beneficiaries of the requirements in the standard NFPA70E, Standard for Electrical Safety in the Workplace . For many organizations, the focus of and improvement in electrical safety programs have largely addressed electrical workers whose primary work tasks involve construction, operation, and/or maintenance of electrical equipment. However, nearly 50% of workplace electrical injuries and fatalities are not of electrical workers. Managers and administrators, painters, truck drivers, farm workers, and grounds keepers and gardeners are among the top ten occupations having the most fatal electrical injuries. For these nonelectrical workers, the exposure to electrical hazards ranges from the use of common portable tools and appliances to unintentional contact with overhead power lines in the course of routine work activities. This paper provides methods to help facilitate the application of specific requirements in NFPA70E and CSA Z462 and other best practices to these “other” workers.
Filtrations, rees rings, and ideal transforms

Let I be an ideal, and let f = {Kn|n ≥ 0 } be a filtration of the Noetherian ring R, such that In ⊆ Kn for all n ≥ 0. We study when the Rees ring R(f) is either finite or integral over the Rees ring R(I), for two types of filtrations f which have recently drawn interest. If I and J are ideals in R, and if m(n) is the least power of J such that (In : Jm(n) + 1), we show that the function m(n) is eventually non-decreasing. For J regular, we characterize when it is eventually constant.
Second-order forced waves in an eccentrically-rotating circular cylinder

The free-surface motion induced by the constant rotation of a fluid-filled circular cylinder about a vertical axis offset from its geometrical center is investigated theoretically. Assuming potential flow, and using a perturbation parameter defined in terms of the axis offset, the theoretical analysis includes terms up to second-order in this parameter. The velocity potentials at first- and second-order are expressed as eigenfunction expansions involving unknown coefficients which are subsequently determined through the boundary conditions. Numerical results are presented that illustrate the influence of the various problem parameters on the free-surface elevation and the induced velocity field in the fluid at both first- and second-order.
Enabling new capabilities and insights from quantum chemistry by using component architectures

Steady performance gains in computing power, as well as improvements in Scientific computing algorithms, are making possible the study of coupled physical phenomena of great extent and complexity. The software required for such studies is also very complex and requires contributions from experts in multiple disciplines. We have investigated the use of the Common Component Architecture (CCA) as a mechanism to tackle some of the resulting software engineering challenges in quantum chemistry, focusing on three specific application areas. In our first application, we have developed interfaces permitting solvers and quantum chemistry packages to be readily exchanged. This enables our quantum chemistry packages to be used with alternative solvers developed by specialists, remedying deficiencies we discovered in the native solvers provided in each of the quantum chemistry packages. The second application involves development of a set of components designed to improve utilization of parallel machines by allowing multiple components to execute concurrently on subsets of the available processors. This was found to give substantial improvements in parallel scalability. Our final application is a set of components permitting different quantum chemistry packages to interchange intermediate data. These components enabled the investigation of promising new methods for obtaining accurate thermochemical data for reactions involving heavy elements.
Function and Structure in Aristotle

Aristote adopte parfois un schema d'inference passant de la complexite du fonctionnement d'une entite a celle de sa structure metaphysique. Cet article soutient qu'Aristote rejette cette inference dans le cas des essences elementaires, qui constituent l'ultime difference permettant de determiner le genre auquel l'entite appartient. Plus precisement, la difference fonctionnelle entre les raisonnements actif et passif chez l'humain n'est pas reflechie dans la structure de son essence elementaire. L'essence elementaire est une unite immediate au sens fort, ce qui veut dire qu'elle est entierement depourvue de parties qui en composeraient la structure. Le fonctionnement rationnel complexe provient d'une essence elementaire qui est metaphysiquement simple.
Observations on cells of the ovotestis of a pulmonate snail

The numerous cytological problems in spermatogenesis and yolk formation have been studied intensively by light microscopists, but it is only recently that electron microscopy has been utilized in an effort to understand the profound nuclear and cytoplasmic changes which take place. The cells of the ovotestis of pulmonate snails offer excellent material for study in these areas. The following report gives an account of studies on both male germ cells and nurse cells of the snail Otala vermiculata including observations for both nuclear and cytoplasmic structures.
PLANAR DIRECTIONAL CONTRIBUTIONS TO OPTIC FLOW RESPONSES IN MST NEURONS

Duffy, Charles J. and Robert H. Wurtz. Planar directional contributions to optic flow responses in MST neurons. J. Neurophysiol. 77: 782–796, 1997. Many neurons in the dorsal region of the medial s...
Optimization of extrinsic source/drain resistance in ultrathin body double-gate FETs

Extrinsic resistance due to contacts and nonabrupt lateral extension doping profile can become a performance-limiter in ultrathin body double-gate FETs (DGFET). In this paper, two-dimensional device simulations are used to study and optimize the extrinsic resistance in a sub-20 nm gate length DGFET. For a given lateral doping gradient, the extension doping needs to be offset from the gate edge by an amount called the underlap. The current drive, and hence transistor performance, is maximized when the underlap is chosen in such a way as to balance the impact of nonabrupt doping on the short channel effects and series resistance. This optimization depends upon the maximum allowed off-state subthreshold leakage current and the electrostatic integrity of the device structure.
Dynamic Coexistence of Frequency Hopping Networks Using Parallel and Gaussian Allocations

This paper studies the coexistence of several independent and dynamic wireless networks using the frequency hopping technique in the unlicensed radio band. We propose a new hopping scheme that allows more networks to collocate effectively, but does not violate federal restrictions regarding frequency constraint (related to the minimum number of frequencies in a hopping set) and time constraint (related to the maximum duration of using a particular frequency). The coexisting networks follow the Gaussian distribution in choosing transmission frequencies from parallel hopping spaces without the overhead of extra message exchange. Simulation results include comparison with other contemporary approaches and establish the viability of the proposed scheme.
Physical Anhedonia, Perceptual Aberration, and Psychosis Proneness

Two groups of hypothetically psychosis-prone subjects were chosen from among college students who scored deviantly high on scales of Physical Anhedonia (n = 50) or Perceptual Aberration (n = 65). Scores on these two scales had a small negative correlation, indicating that the scales identify different sets of deviant subjects. These experimental subjects and a control group (n = 66) were interviewed using a modification of the Schedule for Affective Disorders and Schizophrenia--Lifetime Version. A second interview covered social and academic adjustment. Psychotic and psychotic-like symptoms (attenuated forms of psychotic experiences) were scored on a recently devised scale of deviancy. The perceptual aberration subjects exceeded the control subjects on each of several psychotic-like experiences (auditory and visual experiences, thought transmission, passivity experiences, aberrant beliefs), as well as on depression, hypomania, social withdrawal, problems of concentration, deviances in communication and speech, and a composite score for schizotypal features. Anhedonics did not differ from controls on psychotic-like experiences but were more socially withdrawn, had less heterosexual interest and activity, and scored higher on the composite score of schizotypal features. The findings support the hypothesis that the scales identify persons who are at risk for psychosis but probably for different psychoses.
α2β1 Integrin and Development of Atherosclerosis in a Mouse Model. Assessment of Risk

Objectives— The α 2 β 1 integrin serves as a collagen or collagen/laminin receptor on many cell types, including endothelial cells and platelets. Many studies indicate that the α 2 β 1 integrin is a critical mediator of platelet adhesion to collagen. Epidemiologic studies suggest a direct correlation between the genetically determined platelet surface density of the α 2 β 1 integrin and the risk of thrombotic diseases, such as myocardial infarction and stroke, in the young, which are well-established complications of atherosclerosis. We have now used the α 2 β 1 integrin–deficient mouse to evaluate the contributions of the α 2 β 1 integrin to the development of atherosclerosis. Methods and Results— We generated wild-type (α 2 +/+ ) or α 2 β 1 integrin–deficient (α 2 −/− ) mice that were also deficient in the apolipoprotein E (ApoE) gene (ApoE −/− ) and compared atherosclerotic lesion development in α 2 +/+ ApoE −/− and α 2 −/− ApoE −/− mice that were fed a high-fat, cholesterol-containing diet for 6 or 15 weeks. Total lesional area did not differ significantly between the α 2 -null animals and the wild-type animals at either 6 or 15 weeks. Conclusions— Our results suggest that risk for arterial thrombotic disease associated with high-level α 2 β 1 integrin expression is not attributable to enhanced development of atherosclerosis per se but may rather be a consequence of thrombotic complications at the plaques.
Pulsed laser characterization of multicomponent polymer acoustic and mechanical properties in the sub-GHz regime

We investigated the acoustic properties in the sub-GHz frequency regime of a multilayer system comprising alternating 100-nm scale TiO2/poly(methyl methacrylate) (PMMA) layers through a laser photoacoustic method, impulsive stimulated thermal scattering (ISTS). The acoustic dispersion curves were determined, and the mechanical properties were extracted from the experimental results.
Mixed explicit/implicit time integration of coupled aeroelastic problems: Three‐field formulation, geometric conservation and distributed solution

A three-field arbitrary Lagrangian-Eulerian (ALE) finite element/volume formulation for coupled transient aeroelastic problems is presented. The description includes a rigorous derivation of a geometric conservation law for flow problems with moving boundaries and unstructured deformable meshes. The solution of the coupled governing equations with a mixed explicit (fluid)/implicit (structure) staggered procedure is discussed with particular reference to accuracy, stability, distributed computing, I/O transfers, subcycling and parallel processing. A general and flexible framework for implementing partitioned solution procedures for coupled aeroelastic problems on heterogeneous and/or parallel computational platforms is described. This framework and the explicit/implicit partitioned procedures are demonstrated with the numerical investigation on an iPSC-860 massively parallel processor of the instability of flat panels with infinite aspect ratio in supersonic airstreams.
Start-Up and Dynamic Modeling of the Multilevel Modular Capacitor-Clamped Converter

This paper will present the analytical proof of concept of the multilevel modular capacitor-clamped converter (MMCCC). The quantitative analysis of the charge transfer mechanism among the capacitors of the MMCCC explains the start-up and steady-state voltage balancing. Once these capacitor voltages are found for different time intervals, the start-up and steady-state voltages at various nodes of the MMCCC can be obtained. This analysis provides the necessary proof that explains the stable operation of the converter when a load is connected to the low-voltage side of the circuit. In addition, the analysis also shows how the LV side of the converter is (1/N)th of the HV side excitation when the conversion ratio of the circuit is N. In addition to the analytical and simulation results, experimental results are included to support the analytical proof of concept.
A Site‐Specific Center Pivot Irrigation System for Highly‐Variable Coastal Plain Soils

The Coastal Plains Soil, Water, and Plant Research Center has been monitoring spatial yield in a test field since 1985, using a conventional corn-wheat-soybean rotation most of that time. Observations of variation in soil and crop response that correlate with yield variation suggest that crop water relations may be the key feature that causes spatial variability in yield for the Southeastern Coastal Plain. Experience with mechanistic modeling indicates that for normal weather years, the final yield is particularly sensitive to variations in soil water, presumably because the surface soil is sandy and rooting volume is limited. These conclusions, plus difficulties encountered in scheduling irrigation under a center pivot on typically variable soils, led the USDA-ARS to desi~n and build a site-specific center pivot capable of differentially irrigating lOO-m areas. A 3-tower commercial center pivot was modified by adding 39 9.2-m manifolds in 13 sections, 3 to a section. The manifolds and nozzles were sized lx, 2x, and 4x, so that octal combinations would provide up to 7x the minimum application depth for a given outer tower speed. At 50% speed, the application depths are 0 to 12.5 mm in 1.8-mm increments. A prograrnrnable controller was attached near the pivot end of the boom, so that it was proximal to but avoided the pivot control panel when the system rotated. The individual manifolds were controlled by a program residing in the progranunable controller, which obtained pivot position and other information via radio modem link with the pivot control panel. Water and nitrogen application has been accomplished using this system on a replicated field experiment. Experience gained during this phase will guide modification of a similar pivot for site-specific water, nutrient, and pesticide management on a typically variable Coastal Plain field.
Characterization of Uranium Speciation in a Metallic Matrix

Three metallic slag samples recovered from the site of their inadvertent creation several decades after the fact were sectioned and analyzed to determine uranium speciation to evaluate environmental behavior as well as assess proliferation resistance of the waste form. Uranium concentration in the highly inhomogeneous samples was up to 5% by weight as determined by gamma spectroscopy. Sample sections were milled in a hardened steel ball mill for x-ray absorption spectroscopy analysis (XAS). Powders were digested in a mixture of heated concentrated nitric acid and peroxide and analyzed for elemental content using ICP-AES and ICP-MS. Though elemental content of the samples varied widely, high concentrations of Al were consistently found. Other metals of significance were Ti, Fe, Ni, Cu, Zn, and Sn. High Pb concentrations were occasionally found. XAS analysis revealed the samples contained primarily uranyl and another phase identified as a uranium-aluminum melt.
The first sequence. Fred Sanger and insulin.

FRED Sanger is an amazingly modest man, and his own retrospective, written after he retired, a delightful prefatory chapter for the Annual Reviews of Biochemistry, is called “Sequences, sequences, and sequences” ([Sanger 1988][1]). In it he describes the paths that led to the successful methods
Oxidation processes and phase changes in metastable Al-Ti mechanical alloys

Oxidation of Al-Ti mechanical alloys with Ti concentrations from 5 to 25 at% was studied and compared to the oxidation of Al powders using thermal analysis in the temperature range of 300–1500 °C in oxygen. Differential scanning calorimetry (DSC) and differential thermal analysis (DTA) with simultaneous thermo-gravimetric analysis (TGA) were used to monitor phase changes and oxidation reactions. Intermediate reaction products were recovered at different temperatures and analyzed using x-ray diffraction (XRD) and scanning electron microscopy (SEM). Oxidation of all samples occurred stepwise. The temperature of the first oxidation step for Al-Ti mechanical alloys correlates with the exothermic formation of the Al3Ti intermetallic at T>700 °C and has a higher rate and greater degree of oxidation than the first oxidation step observed for pure aluminum. The second and third oxidation steps in mechanical alloys and aluminum occur at higher temperatures and both appear to be controlled by changes in the permeability of the Al2O3 films. The effect of the Al2O3 film becomes less noticeable at increased Ti concentrations.
A Distributed algorithm for mobile robot localization and mapping in wireless sensor networks

This paper presents a navigation and mapping technique that integrates the global view of a wireless sensor network and the local advance sensing of mobile robots. Search and rescue missions rely on robots that can successfully navigate through an indoor environment which may be undefined and filled with unpredictable obstacles. The onboard sensors and local navigation schemes can provide obstacle avoidance and help robots navigate locally, but not for a long distant goal due to lack of global knowledge and problems of local minima. Therefore some help from the environment were proposed in many previous works such as visual landmarks, or radio signal transmitted from Wi-Fi beacons or wireless sensor networks. The latter, which involves many sensor nodes, if deployed in well-organized formation, can serve as signposts that will help mobile robots for navigation. Hence the need for a predefined map can be eliminated. By utilizing robots on-board sensors to process the received data from near-by nodes and combining it with the on-board sensed data, the algorithm we propose will provide the ad hoc SLAM capability to both robots and wireless sensor network which in turn can guide the robot to its destination at the same time.