cssi/SciSciGPT-SciSciNet huggingface dataset:
Geometric construction of balanced block designs with nested rows and columns

A new series of balanced block designs with nested rows and columns is constructed using the finite Euclidian geometry. Some such designs along the line of Cheng (1986) are also considered. A result on the system of distinct representatives is seen to be helpful in the derivation.
Polysiphonia boldii sp. nov. from Texas

Abstract Polysiphonia boldii sp. nov. is described from the Texas coast of the Gulf of Mexico. Its chief features are: six pericentral cells, paired spermatangial branches, endogenous branches not associated with trichoblasts, and a pronounced prostrate system.
The asymptotic stochastic strength of bundles of elements exhibiting general stress-strain laws

Abstract The fiber bundle model is widely used in probabilistic modeling of various phenomena across different engineering fields, from network analysis to earthquake statistics. In structural strength analysis, this model is an essential part of extreme value statistics that governs the left tail of the cumulative probability density function of strength. Based on previous nano-mechanical arguments, the cumulative probability distribution function of strength of each fiber constituting the bundle is assumed to exhibit a power-law left tail. Each fiber (or element) of the bundle is supposed to be subjected to the same relative displacement (parallel coupling). The constitutive equations describing various fibers are assumed to be related by a radial affinity while no restrictions are placed on their particular form. It is demonstrated that, even under these most general assumptions, the power-law left tail is preserved in the bundle and the tail exponent of the bundle is the sum of the exponents of the power-law tails of all the fibers. The results have significant implications for the statistical modeling of strength of quasibrittle structures.
Throughput Optimization in Energy Sharing Wireless Sensor Networks

Energy harvesting is becoming an important enabling technology for sustainable sensor networks. However, the uncertainty and non-uniformity of harvestable energy and the unbalanced workload will often result in the node failures of solar-powered sensor networks. In order to decrease the energy depletion and improve the performance, we introduce an ultra-capacitor-based energy sharing system and design an energy sharing scheme based on it to optimize the network throughput. Different from most of the existing approaches which are focusing on energy management on single node, our design considers energy as a shared resource which makes it be used more efficiently, especially in the case with limited energy. Theoretical analysis and simulation results indicate the energy sharing system as well as the energy sharing schemes can effectively improve the network performance.
Investigating the penalty reward calculus of software users and its impact on requirements prioritization

ContextThe current requirements engineering techniques for prioritization of software requirements implicitly assume that each user requirement will have an independent and symmetric impact on user satisfaction. For example, it is assumed that implementing a high priority user requirement will positively impact his satisfaction and not implementing a high priority user requirement will negatively impact his satisfaction. Further, the impacts of implementing multiple user requirements on his satisfaction are expected to be additive. But is this always the case? ObjectiveThis paper empirically examines whether the assumptions of symmetric and multiplicative impacts of user requirements on his satisfaction are valid. Further, the study assesses the relative efficacy of 5 methods of requirements prioritization in managing these effects as reflected by the user satisfaction with the prioritized requirement sets. MethodTo test for existence and mitigation of asymmetric effects an adaptation of the widely accepted PRCA (Penalty Reward Contrast Analysis) method was used for 5 requirements prioritization techniques. To test for existence and mitigation of multiplicative effects MHMR (Moderated Hierarchical Multiple Regression) a well-accepted technique for testing interaction effects was used. ResultsBoth asymmetric and multiplicative effects of software requirements on user satisfaction were observed for requirements prioritized using all 5 requirements prioritization methods raising questions about the efficacy of present day requirements prioritization techniques. Further, the results of the experiment led to proposing a new method for requirements prioritization for managing these effects. ConclusionThe study empirically demonstrates the complexities of prioritizing software requirements and calls for a new generation of methods to address them. Understanding and resolving these complexities will enable software providers to conserve resources by enabling them to parsimoniously selecting only those requirements for implementation in the software product that have maximum incremental impact on user satisfaction.
The Eighty-Hour Workweek: Surgical Attendings' Perspectives

Objective The year 2008 was a sentinel year in resident education; this was the first graduating general surgery class trained entirely under the 80-hour workweek. The purpose of this study was to evaluate attending surgeon perceptions of surgical resident attitudes and performance before and after duty-hour restrictions. Design An electronic survey was sent to all surgical teaching institutions in North Carolina. Both surgeon and hospital characteristics were documented. The survey consisted of questions designed to assess residents' attitudes/performance before and after the implementation of the work-hour restriction. Results In all, 77 surveys were returned (33% response rate). The survey demonstrated that 92% of educators who responded to the survey recognized a difference between the restricted residents (RRs) and the nonrestricted residents (NRRs), and most respondents (67%) attributed this to both the work-hour restrictions and the work ethic of current residents. Most attending surgeons reported no difference between the RRs and the NRRs in most categories; however, they identified a negative change in the areas of work ethic, technical skills development, decision-making/critical-thinking skills, and patient ownership among the RR group. Most surgeons expressed less trust (55%) with patient care and less confidence (68%) in residents' ability to operate independently in the RR group. Eighty-nine percent indicated that additional decreases in work hours would continue to hamper the mission of timely and comprehensive resident education. Conclusions The perception of surgical educators was that RRs are clearly different from the NRRs and that the primary difference is in work ethic and duty-hour restrictions. Although similar in most attributes, RRs are perceived as having a lower baseline work ethic and a less developed technical skill set, decision-making ability, and sense of patient ownership. Subsequent study is needed to evaluate these concerns.
Factions and Communities in Early Modern Central Europe

On 12 November 1745, the ad hoc militias of two peasant factions collided near Schmitzingen, a small village in the Black Forest country of Hauenstein, which constituted the southeastern quarter of the Habsburg province of Outer Austria. Several days before, the larger of the two forces had laid siege to Waldshut, the administrative seat of Hauenstein. The smaller band of peasants, recruited from cantons in the north of Hauenstein, had marched through the night to relieve the town. As it approached Waldshut, this relief force was ambushed, encircled, and routed. Two peasants died from wounds suffered in the melee, and many more were severely wounded.
Recirculating mixed convection flow for energy extraction

Abstract Energy may be extracted from the sensible heat stored in a body of fluid by means of a recirculating flow. A numerical study of the time-dependent, two-dimensional, laminar, convective flow that arises is carried out. The hot fluid is withdrawn at the top and the cold fluid discharged at the bottom of the storage region to preserve the thermal stratification. The nature of the flow is found to be very strongly affected by the buoyancy and the flow configuration. Numerical results are presented over a wide range of governing parameters, that arise from the inflow conditions, flow configuration and the heat transfer mechanisms at the boundaries.
Effects of diisopropyl phosphofluoridate, sarin and soman on the accessibility of proteins, in the electroplax membrane, to lactoperoxidase-catalyzed iodination.

Abstract Anticholinesterases (anti-ChE) have some effects on biological properties including behavior, vision, and electroencephalograms, which are often long lasting and which do not appear to be due to cholinesterase (ChE; EC 3.1.1.7) inhibition, but which may be due to alterations in the organization and/or functioning of the cellular membrane. We assessed the effects of anti-ChE agents on the asymmetric organization of proteins in the innervated (excitable) and in the non-innervated (non-excitable) plasma membrane of the electroplax from the electric eel. Lactoperoxidase-catalyzed iodination (LCI) was carried out under impenetrable conditions in intact electroplax (where protein exposure on the external surface is monitored) and in split electroplax (where total protein labeling on both the external and internal monolayers of the plasma membrane bilayer is monitored). Labeling in split electroplax was much greater than in intact electroplax for all molecular weight groupings of proteins (30,000 to > 200,000). The anti-ChE agents diisopropyl phosphofluoridate (DFP; 10 −3 M), sarin (10 −4 M) and soman (10 −4 M, 10 −6 M, 2.5 × 10 −9 M) did not alter permeability, protein content or the electrophoretic pattern of the plasma membrane proteins of the electroplax. DFP, sarin and 10 −6 M soman (but not 2.5 × 10 −9 M or 10 −4 M soman) increased labeling of some of the molecular weight fractions in the non-innervated plasma membrane as monitored by LCI in intact electroplax. Under these same conditions, DFP and 10 −4 M soman increased labeling in the innervated plasma membrane while 10 −6 M soman decreased labeling. When LCI was carried out in split electroplax, 10 −4 M soman caused a decrease in labeling in both the innervated and non-innervated plasma membrane indicating a decrease of exposed proteins on the cytoplasmic surface of the plasma membrane. These concentrations of the anti-ChE agents caused almost complete ChE inhibition in the electroplax cells, except for 2.5 × 10 −9 M soman which caused little or no inhibition. These results suggest that alterations in protein asymmetry, as monitored by LCI of accessible proteins, are not directly due to ChE inhibition. These changes in organization of membrane proteins could contribute to a variety of effects of anti-ChE agents which are not due to ChE inhibition.
Assessment of Pediatric Residents' Otoscopic Interpretive Skills by Videotaped Examinations

Background.—Accurate diagnosis of otitis media is essential to facilitate appropriate management. Few residency programs assess formally their residents' competency in diagnosing middle ear disease. Objective.—To evaluate the performance of pediatric residents' otoscopic interpretive skills by level of training, with a videotaped otoendoscopic examination (VOE). Methods.—A VOE was used to assess and compare the performance of a cross-sectional sample of 141 residents with one another by level of training as well as with novice and expert groups. Total score, sensitivity, specificity, and kappa coefficients were calculated for each subject by comparing the subject's answers on the 50-ear test with the VOE's expert panel–derived answers, and averages were determined for each training level. Results.—Each pediatric resident training group had moderate agreement (mean κ coefficient range: .45–.56) with the VOE answers, compared with the novice group (mean κ: .31, fair) and expert group (mean κ: .80, substantial). Twenty-eight residents (20%) had fair or less agreement (κ Conclusions.—We found the VOE to be a feasible and reliable instrument to accurately distinguish novice, resident, and expert level skills in the determination of middle ear effusion status.
The Impact of Recent Changes in the Epidemiology of Dental Caries on Guidelines for the Use of Dental Sealants

This paper reviews recent changes in the epidemiology of dental caries and assesses their potential impact on the diagnosis and management of the disease and the planning and operation of sealant programs. These changes, such as the decline in caries and slowing of the rate of progression of the disease, have important implications for diagnosing and treating incipient lesions, predicting caries risk, and conducting effective disease preventive programs. Traditional paradigms for restoring carious lesions are being replaced by newer strategies that emphasize disease prevention and conservation of tooth structure. The search continues for the identification of practical models for predicting caries risk at the individual level. This paper describes a method useful for targeting resources in sealant placement programs by enabling one to determine the relative effectiveness of sealing alternative tooth surfaces in the oral cavity. One guide serves as a widely adopted manual for those who use or intend to use dental sealants in caries prevention programs. This paper provides a brief review of that document, "Preventing Pit and Fissure Caries: A Guide to Sealant Use," as well as guidelines for sealant utilization provided by the American Dental Association, and information regarding dental sealant programs under Medicaid. The final portion of the paper provides a synthesis of the epidemiology reviewed and summarizes the implications of findings for sealant programs.
WATER EXCHANGE OF COLLAGENOUS TISSUES AND OF GELATIN

Water exchange of parenchymatous tissue, namely liver, kidney, or pancreas, occurs by osmosis, and the movement of water, as is well known, occurs in direct relation to the concentration of the surrounding solution. But the present work shows that the hydration of collagenous tissues, like that of gelatin, occurs in strong as well as in weak solutions of sodium chloride. The water intake of collagenous tissue in solutions of sodium chloride or of sucrose increases with increased density of the tissue and the sequence of changes is like that observed with gels of increasing gelatin content under the same conditions. Dense collagenous tissue, apparently impervious to the movement of water, exhibits a conspicuous ability to attract and hold it.
The culture question in participatory design

As efforts to promote Participatory Design (PD) outside of the Nordic region have grown, how to deal with culture has been perceived as an increasingly pressing issue. This paper explicates the cultural problems PD has had and presents alternative approaches to dealing with them.Anthropology is a discipline that has largely been organized through debates about culture. The paper draws on this discourse to argue against PD's tendency to conceive of culture as a single, unified "thing" with ontological status. Rather, cultural perspectives are produced via use of analytic constructs. PD can develop culturally appropriate senses of both participation and design by learning to decompose totalizing notions of culture. One can begin by separating from each other the aspects of culture relevant to a particular PD project, dealing serially with each of them, and only then attempting to construct a "holistic" cultural account. The argument is largely theoretical, an effort to apply the approach being contained in another paper on what happened when PD was tried in Mozambique.
Temporal and spatial analysis of electrogenerated Ru(bpy)33+ chemiluminescent reactions in flowing streams

The effect of hydrodynamics on chemiluminescence (CL) emission is investigated for the tris(2,2‘-bipyridine)ruthenium(II/III) (Ru(bpy)32+/3+) electrogenerated chemiluminescence (ECL) system in solution phase and immobilized in Nafion. The maximum CL emission is obtained at low linear velocities for slow reactions, at intermediate linear velocities for reactions with intermediate kinetics, and at high linear velocities for fast reactions. Relative kinetic information for a variety of analytes is acquired by comparing charge-coupled device (CCD) images to stopped-flow and flow injection analysis data obtained with a photomultiplier tube (PMT). CCD images are also utilized to observe reproducibility and homogeneity of different Nafion film preparations. The spatial resolution provided by the CCD allows a more comprehensive analysis of the effects of flow on observed CL reaction kinetics than is possible with a PMT. These studies yield important guidelines for application and optimization of CL detection in f...
Stokes Shift Spectroscopy and Imaging for highlighting the difference of breast cancerous and normal tissues

Stokes Shift Spectroscopy (S3) and imaging offer a novel way to rapidly measure spectral fingerprints of fluorophores in tissue, which highlights the difference of cancerous and normal tissues.
A note on minimax estimation and Kalman filtering

A minimax estimator for the state of a discrete time-varying linear plant with an a priori unknown control sequence is developed. No statistics for the sequence of control vectors are assumed to exist. It is assumed, however, that the a priori unknown control sequence can be measured in additive Gaussian noise with zero mean and known variance.
Spirometric patterns in childhood asthma: Peak flow compared with other indices

The objective of this study was to determine patterns of pulmonary function abnormalities and to evaluate how adequately peak flow monitoring was correlated to other spirometric indices in childhood asthma. Ninety-one children, aged 8-15 years, with moderate-to-severe asthma were repeatedly tested in a summer camp. On-site medical staff permitted 24-hour-a-day supervision. Subjective and objective clinical evaluations of asthma status were made over 14 consecutive days. Detailed clinical history and clinical observations were made by an experienced staff, and a total of 2,663 pulmonary function tests were performed regularly three times daily and whenever a child sensed asthma symptoms. Patterns of obstruction were divided into large airway abnormalities and small airway abnormalities. There was a low concordance between standard large airway measures, such as the peak expiratory flow rate (PEFR) or the forced expiratory volume in 1 second (the FEV1), and measures of small airway obstruction, such as the forced expiratory flow rate 25-75% (FEF25–75). Normal PEFR measurements do not always indicate that all other pulmonary function measures are normal. In fact, 18% of children with a normal PEFR had abnormal FEF25–75 values. Results demonstrated that the FEF25–75 was the most specific and sensitive measure of airway obstruction. PEFR is widely used to monitor asthma symptoms objectively because it is technically simple to perform, relatively inexpensive, and helpful in most cases. It is, therefore, appropriate for asthma education programs to recommend PEFR as an objective measure to guide in making therapeutic decisions. Our data and clinical observations support the “Guidelines for the Diagnosis and Management of Asthma” of the NIH Health Asthma Education Program that suggest that children have more complete pulmonary function testing along with frequent PEFR measures. Many children may appear asymptomatic, while recording normal PEFR measures, and still having significant asthma. Repeated pulmonary function testing and evaluation of the pattern of respiratory obstruction aids in managing this challenging group. We recommend that efforts be made to develop a simple and inexpensive method of measuring FEF25–75 that will allow this measurement to be made even at home. Pediatr Pulmonol. 1995; 20:372–379. © 1995 Wiley-Liss, Inc.
Neuropsychological Correlates of the Electroencephalogram in Epileptics: II. The Waking Posterior Rhythm and its Interaction with Epileptiform Activity

Relationships between psychological functions and waking dominant posterior rhythm frequency (DPRF) of the EEG were evaluated with and without simultaneous evaluation of epileptiform discharges. Ninety adult epileptics with uncontrolled seizure disorders treated solely by diphenylhydantoin underwent EEGs during wakefulness and administrations of an extensive battery of neuropsychological tests. The DPRF was particularly related to abilities simultaneously requiring attention an complex mental manipulations. Rhythms slower than 7.5-8.0 Hz were accompanied by relatively poorer performance than rhythms which were faster. When epileptiform discharges were considered in combination with the DPRF, larger differences in abilities were demonstrated, and the psycholoigcal correlates tended to be more substantial for the epileptiform discharge variable than for the DPRF variable. The selection of tests employed and the range of rhythms assessed are critical to these findings, and the substantial construction of these variables by many previous investigators is believed to be related to the negative findings often reported.
Multimonopoles in arbitrary gauge groups and the complete SU(2) two-monopole system

We show how to extract exact expressions for the multimonopole gauge fields and Higgs field from their integral representation in the Atiyah-Drinfeld-Hitchin-Manin-Nahm (ADHMN) construction, for arbitrary gauge groups. In particular, this allows us to construct the complete two-monopole solution for the SU(2) gauge group.
Field Emission from Niobium in the Normal and Superconducting States

The change of field emission current from a superconductor as a result of a transition to the normal state under constant field and temperature conditions was calculated. The derivation is based on the Bardeen-Cooper-Schrieffer formulation of the density of states and band gap model for a superconductor. The experimental method for determining the current change consisted in measuring the current increment between a niobium field emitter in the superconducting state at 4.2\ifmmode^\circ\else\textdegree\fi{}K and in the normal state at a temperature $T$ above the transition. After correcting for the current increase occurring as a result of the temperature increase alone, the residual would be that associated with the superconducting-normal transition. This was less than the detectability of the measurements, although the calculations indicated an expected increase in current easily measurable if the superconducting-normal transition had occurred at the emitter surface. It is speculated that under high-field conditions, the superconducting state is quenched at the surface.
Evidence for intrinsic electrical conduction in the linear metal-chain semiconductor bis(1,2-benzoquinonedioximato)platinum(II), Pt(bqd)2

Abstract The four-electrode dc conductivity of single crystals of the linear metal-chain compound bis(1,2-benzoquinonedioximato)platinum(II), Pt(bqd)2, measured parallel to the long axis of the crystals, reveals ohmic behavior over the temperature range 77–550°K, and averages to σ = 3.3 × 10 −3 Ω −1 cm −1 at room temperature. Unlike the well-characterized Magnus' Green Salt (MGS), Pt(NH3)4PtCl4 ( σ = 5.5 × 10 −4 Ω −1 cm −1 ) , the present compound is found to be an intrinsic, small band gap semiconductor. The PtPt distance of 3.180 A, the shortest yet observed in Pt(II) glyoximates, was determined by powder X-ray diffraction. The small band gap is related to the unusually high conductivity of Pt(bqd)2, which is most reasonably interpreted in terms of this short PtPt separation. Preliminary results of polarized single crystal reflectance spectra demonstrating the anisotropic behavior of this compound are presented.
Sex effects and sentencing: An analysis of the statistical literature

We analyze the statistical literature on gender and sentencing to determine whether findings of “sex effects” favoring women are related to the statistical procedures used, to court contexts and sample composition, and to conceptual dimensions of the research. The unit of analysis (or case) is court data sets; our search identified 50 such cases, most of which analyze data from the 1970s. Half of these showed sex effects favoring women; one-quarter each showed mixed effects or no effects. These proportions remained constant when the sample was weighted by a quality score. In comparison with Kleck's review of race and sentencing, sex effects favoring women are far more frequent than race effects favoring whites. Results from the weighted sample suggest that sex effects are evident in both recent and older data sets and in both recent and earlier published work. They are more likely to emerge in analyses of felony offenses, in offenses prosecuted in felony courts, in courts in urban areas, and in the decisi...
Experimental test of morphological stability theory for a planar interface during rapid solidification

We report a parameter-free test of the theory predicting the critical solute concentration that destabilizes a planar solid-liquid interface in the high-velocity regime where nonequilibrium interface kinetics are important. Rapid solidification following pulsed laser melting was used to make metastable solid solutions of silicon-tin. Rutherford backscattering spectrometry and transmission electron microscopy were used to measure the breakdown concentration. Samples remained microsegregation free with near perfect crystallinity at tin concentrations up to 10 times the maximum equilibrium solubility and 100 times that predicted by linear stability theory with local interfacial equilibrium. These measurements, covering velocities from 1 to 10 m/s, agree with the predictions of linear stability theory when the latter incorporates a velocity-dependent partition coefficient and a thermodynamically consistent kinetic liquidus, and contains no adjustable parameters. We also report a systematic increase of the breakdown concentration with increasing deviation from steady-state conditions, which is not addressed by current stability theories, parametrized by the concentration gradient just prior to breakdown.
Numerical simulation of a simulated countercurrent moving bed chromatographic reactor

A mathematical model of a simulated countercurrent moving bed chromatographic reactor (SCMCR) has been developed. The model represents a multiple column reactor consisting of a series of either four or five tubular fixed beds packed with a mixture of catalyst and adsorbent, with a port that can serve either as an inlet or an outlet between each. A reversible first order reaction, A /agB, with rate coefficients and rate parameters taken from the hydrogenation of 1,3,5-trimethylbenzene is incorporated into the model. The partial differential equations governing the isothermal reactor at 463 K are solved by an adaptive finite element method with uneven grid points. Model predictions of concentration profiles in the columns, and overall reactor performance, are obtained. It is shown that reaction and separation occur simultaneously, and that the conversion of this equilibrium limited reaction is greatly increased over the 0.62 that would be the maximum obtainable in a non-separative system. Under appropriate operating conditions, the model calculations predict that high product purity streams (98–99%) and nearly unit conversions can be obtained.
Studying stress-induced morphological evolution with the discrete atom method

This article presents an overview of the discrete atom method and recent findings concerning general coherency problems. Continuum linear elasticity on coherence strain is also reviewed along the framework of Eshelby’s inclusion theory.
Database considerations in a technology-transfer network

A computer-based network to support technology transfer between campuses of the California State University and local industry is described. Options associated with designing the database and configuring the hardware are evaluated. The TECHNET system involves 20 campuses of the state university system and is designed to support 1,000 industrial firms. The database consists of faculty expertise in the forms of resumes and company products and capabilities. Member companies may query the database to identify faculty (preferably at a local campus) and/or another company that can help them solve technological and business problems. The benefit of TECHNET to companies in addition to problem solving is new business opportunities and to faculty is consulting opportunities. The work is supported by the California Competitive Technology Project office of the California Department of Commerce.
Matching unit load and inventory system

Abstract The cost of handling and storing materials are important elements in the total cost of inventory. Existing models do not appear to address these elements in a suitable way. This paper considers the special problem of unit handling, where the appropriate method is selected with respect to different inventory cost models. A computer program has been developed which can be used to carry out the required calculations and both the method and the computer program are illustrated by a numerical example.
On the Universal Embedding of the U2n(2) Dual Polar Space

A. E. Brouwer has shown that the universal embedding of the U2n(2) dual polar space has dimension at least (4n+2)/3 and has conjectured equality. The present paper proves this conjecture by establishing a related result about permutation modules for GLn(4). The method is the same used in the author's previous paper on an analogous question for the Sp2n(2) dual polar space.
Cognitive behavior therapy of endogenous depression: Part 2: Preliminary findings in 16 unmedicated inpatients

A series of 16 unmedicated hospitalized depressed patients were treated with an intensive (5 sessions per week) course of cognitive behavior therapy (CBT) as an alternative to pharmacotherapy. Outcome at discharge (following an average course of 13 sessions) was excellent, both in terms of response rate (13/16; 81%) and symptomatic improvement (p's
A kinase-mediated regulation of granulosa cell-derived insulin-like growth factor binding proteins (IGFBPs): disparate response sensitivities of distinct IGFBP species.

Rat granulosa cell-derived insulin-like growth factor (IGF) binding proteins (BPs) have been found subject to biphasic dose-dependent regulation by FSH under in vitro circumstances. Since cAMP may play an intermediary role in FSH hormonal action, we have undertaken to characterize the A kinase-mediated regulation of the elaboration of IGFBPs by cultured rat granulosa cells. Treatment with increasing concentrations of prostaglandin E2 or choleragen, both established cAMP-generating agonists, produced biphasic dose-dependent regulation of the release of the major 28-29 kilodalton (kDa) IGFBP species while promoting the release of their minor 24 (and 19) kDa counterparts. Similar effects were noted for other cAMP-generating agonists including vasoactive intestinal peptide and forskolin (a potent activator of adenylate cyclase). Moreover, concomitant treatment with a functionally inert low dose (10(-7) M) of forskolin, substantially potentiated the FSH (10 ng/ml)-mediated inhibition of the elaboration of the ...
Application of a nonlinear stress-strain model to axisymmetric turbulent swirling flows

Abstract A nonlinear stress-strain relation (NLSM) for the turbulence stresses is applied to axisymmetric free shear flows with and without swirl. This relation is an explicit solution to an algebraic Reynolds stress model (ARSIVI). The stress relation is a finite sum of tensor groups depicting various interactions between the mean strain and vorticity fields. Implementation is in the context of a k −e type model. Comparisons are made between flow field predictions obtained with the full Reynolds stress model, the NLSM corresponding to improved and standard ARSMs, the k −e model and experimental data.
Detection of gangliosides that bind cholera toxin: direct binding of 125I-labeled toxin to thin-layer chromatograms.

Abstract Gangliosides that bind cholera toxin can be detected by the direct binding of 125 I-labeled toxin to thin-layer chromatograms followed by autoradiography. The method is very sensitive: 0.1 ng of G M1 (70 fmol) can be detected on chromatograms of total lipid extracts of cells. The method may be useful in defining the receptors of other toxins or proteins such as some lectins, antibodies, and hormones that bind carbohydrates.
Expanding maps on compact metric spaces

Abstract The notions of locally expansive, positively expansive, expanding in the sense of Ruelle and expanding in the sense of Duvall and Husch are equivalent in a quite general setting.
Developmental and hormonal regulation of cholesterol side chain cleavage cytochrome P-450 in the fetal rabbit testis.

Abstract Male sexual differentiation is dependent upon the induction of testosterone synthesis by the fetal testis at a critical phase of development. In the rabbit, testosterone synthesis by the fetal testis is initiated after 17.5–18 days of gestation, reaches peak values by day 21 and subsequently declines. In the present study, we analyzed the specific activity and concentration of immunoreactive cholesterol side chain cleavage cytochrome P -450 (cytochrome P -450 scc ) in the fetal rabbit testis during development to assess its possible role as a key regulatory enzyme in fetal testicular Steroidogenesis. The effects of human chorionic gonadotropin (hCG) and dibutyryl cyclic AMP on the specific activity and synthesis of cytochrome P -450 scc in fetal rabbit testes in vitro also were evaluated. We observed that changes in cholesterol side chain cleavage activity paralleled the induction of testosterone synthesis; the specific activity of this enzyme which was ⋍- 0.25 pmol min −1 mg −1 protein in testes from 19-day fetal rabbits was increased ⋍- 10-fold in testes of 21-day fetuses and thereafter declined dramatically. Immunoreactive cytochrome P -450 scc , which was first detectable in gonads of 19-day fetal rabbits, was induced markedly in 21-day fetal testes, reached maximum levels on day 24 and declined slightly thereafter. Incubation of testes from 19-and 21-day gestational age fetal rabbits with hCG or dibutyryl cyclic AMP for 24 h resulted in an induction of testosterone synthesis, cholesterol side chain cleavage activity and synthesis of cytochrome P -450 scc . These findings are suggestive that androgen synthesis by the fetal Leydig cell is mediated by an induction of the synthesis and specific activity of cytochrome P -450 scc . In addition, these data support the hypothesis that the developmental changes in the synthesis of cytochrome P -450 scc are regulated by fetal gonadotropin and are mediated by cyclic AMP.
Left brain, right brain: One brain, two brains

It is an odd assignment, this one: not as a non-neuroscientist the request to write a review of a book on the structure and functioning of the left and right hemispheres of the brain, for The master and his emissary is after all aimed at the intelligent general reader, and in this context I can at least lay claim to being a general reader; but rather the invitation to make such an assessment for a journal whose readership is largely confined to neurologists and neuroscientists, an audience whose expertise on the underlying brain science is orders of magnitude greater and more sophisticated than mine. How to tackle such a task? It makes no sense for me to devote much space to a critique of Iain McGilchrist’s mastery of the research literature on which he draws to make his case, for there are literally thousands of reviewers more competent than I to undertake such an assessment. Instead, like other non-specialist readers, I must perforce take largely on trust his claims to represent the current state of neuroscientific knowledge, and will turn most of my attention elsewhere: to where his analysis sits in a long-running historical debate on the duality of the brain; and to an examination of his attempt to move from the narrow findings of neuroscience to a remarkably bold and ambitious attempt to understand their implications for, as he puts it in his subtitle, ‘the making of the Western world’. ![Graphic][1] That human and mammalian brains are composed of two hemispheres has long been known. Greek physicians from the third century before the Christian Era knew of and speculated about the divided brain, and McGilchrist mentions, largely in passing, that Galen’s anatomical researches, mostly conducted on animals, made this basic duality of the brain known to all interested parties from … [1]: /embed/inline-graphic-1.gif
Distribution of glutamic acid decarboxylase (Mr 67,000) in the basal ganglia of the rat: an immunohistochemical study with a selective cDNA-generated polyclonal antibody.

Distinct isoforms of glutamic acid decarboxylase, the synthetic enzyme for GABA, exist in brain. Their distribution at the cellular level is not known, because previous studies have been confounded by the lack of monospecificity of available antibodies. We have examined the distribution of glutamic acid decarboxylase (Mr 67 000; GAD67) in the basal ganglia of the rat with a polyclonal antibody generated against the protein expressed in bacteria transformed with the corresponding cDNA. This antibody, which is directed against a portion of GAD67 non homologous to other known glutamic acid decarboxylase isoforms, selectively recognizes GAD67 on western blots. We show that GAD67 is present to various degree in all types of GABAergic neurons previously described in these regions. In contrast with results obtained with non-selective antibodies for glutamic acid decarboxylase, GAD67-positive neuronal cell bodies were readily detected in sections of the striatum, pallidum and substantia nigra in the absence of colchicine treatment. Modifications in the immunohistochemical procedure favoured staining of glutamic acid decarboxylase-positive fibres with the same antibody, indicating that GAD67 is also present in axon terminals of GABAergic neurons. The results suggest that GAD67 may be involved in GABA synthesis in both cell bodies and axon terminals of all GABAergic neurons of the basal ganglia, but is particularly abundant or accessible in their cell bodies.
Scale- and rotation-invariant pattern recognition by a rotating kernel min-max transformation

A new hybrid optical/digital method for scale- and rotation-invariant pattern recognition is presented using a rotating kernel mm-max transformation. In this method, the input object is convolved with a long, narrow 2-D kernel. As the kernel rotates, the convolution output is monitored and the maximum [=Maxl and minimum [=MinJ values, along with the angle °M at which Max is found, are stored. The processed object is given by some function f[ , I of Max and Mm values. From the description (f[ , , OM), the 9-projection is first calculated. To obtain scale invariance, this projection is normalized by its integral. The normalized 0-projection exhibits an approximate scale invariance, the recognition capability depending to a small degree on the kernel length used. Since the kernel rotates, rotation invariance is achieved. Results of numerical experiments are presented. Some effects that variations in the kernel length have on the discrimination of objects are discussed.
New photocycle intermediates in the photoactive yellow protein from Ectothiorhodospira halophila: picosecond transient absorption spectroscopy.

Abstract Previous studies have shown that the room temperature photocycle of the photoactive yellow protein (PYP) from Ectothiorhodospira halophila involves at least two intermediate species: I 1 , which forms in μ s lifetime to I 2 , which itself subsequently returns to the ground state with a 140-ms time constant at pH 7 (Genick et al. 1997. Biochemistry . 36:8–14). Picosecond transient absorption spectroscopy has been used here to reveal a photophysical relaxation process (stimulated emission) and photochemical intermediates in the PYP photocycle that have not been reported previously. The first new intermediate (I 0 ) exhibits maximum absorption at ∼510nm and appears in ≤3ps after 452nm excitation (5ps pulse width) of PYP. Kinetic analysis shows that I 0 decays with a 220±20ps lifetime, forming another intermediate (I ‡ 0 ) that has a similar difference wavelength maximum, but with lower absorptivity. I ‡ 0 decays with a 3±0.15ns time constant to form I 1 . Stimulated emission from an excited electronic state of PYP is observed both within the 4–6-ps cross-correlation times used in this work, and with a 16-ps delay for all probe wavelengths throughout the 426–525-nm region studied. These transient absorption and emission data provide a more detailed understanding of the mechanistic dynamics occurring during the PYP photocycle.
ThYme: a database for thioester-active enzymes

The ThYme (Thioester-active enzYme; http://www.enzyme.cbirc.iastate.edu) database has been constructed to bring together amino acid sequences and 3D (tertiary) structures of all the enzymes constituting the fatty acid synthesis and polyketide synthesis cycles. These enzymes are active on thioester-containing substrates, specifically those that are parts of the acyl-CoA synthase, acyl-CoA carboxylase, acyl transferase, ketoacyl synthase, ketoacyl reductase, hydroxyacyl dehydratase, enoyl reductase and thioesterase enzyme groups. These groups have been classified into families, members of which are similar in sequences, tertiary structures and catalytic mechanisms, implying common protein ancestry. ThYme is continually updated as sequences and tertiary structures become available.
Prior stressor exposure primes the HPA axis

Exposure to stressors often alters the subsequent responsiveness of many systems. The present study tested whether prior exposure to inescapable tailshock (IS) alters the corticosterone (CORT) or adrenocorticotropin hormone (ACTH) response to either an injection of bacterial endotoxin (lipopolysaccharide; LPS) or subsequent placement on a pedestal. Rats were exposed to IS or remained as home cage controls (HCC). 1, 4, 10, or 21 days later animals were injected i.p. with either 10 µg/kg LPS or equivolume sterile saline. Prior IS significantly increased plasma CORT 1 h, but not 2 or 5 h after LPS, compared to controls 1, 4, and 10 days, but not 21 days after IS. Exposure to IS 24 h earlier also significantly increased plasma ACTH 1 h after LPS. Additional animals were placed on a pedestal 24 h after IS, and plasma CORT was measured 15, 30, and 60 min later. IS significantly increased plasma CORT 15 min after pedestal exposure, but not after 30 or 60 min. These results suggest that exposure to IS sensitizes the CORT and ACTH response to subsequent HPA activation.  2002 Elsevier Science Ltd. All rights reserved.
Pathology of tumors in fish associated with retroviruses: a review.

Thirteen proliferative diseases in fish have been associated in the literature with 1 or more retroviruses. Typically, these occur as seasonal epizootics affecting farmed and wild fish, and most lesions resolve spontaneously. Spontaneous resolution and lifelong resistance to reinfection are 2 features of some piscine retrovirus–induced tumors that have stimulated research interest in this field. The purpose of this review is to present the reader with the epidemiological and morphological features of proliferative diseases in fish that have been associated with retroviruses by 1 or more of the following methods: detection of C-type retrovirus-like particles or reverse transcriptase activity in tumor tissues; successful tumor transmission trials using well-characterized, tumor-derived, cell-free inocula; or molecular characterization of the virus from spontaneous and experimentally induced tumors. Two of the diseases included in this review, European smelt spawning papillomatosis and bicolor damselfish neu...
An 8-18-GHz all-optical microwave downconverter with channelization

A wide-band fiber-optic image-rejection downconverter capable of channelizing received signals into a 500-MHz intermediate frequency band is demonstrated. The downconverter utilizes phase modulators to convert received signals into optical side-bands prior to heterodyne detection with the system local oscillator. Experimental measurements performed on a two-channel system which maps 8-18-GHz signals into intermediate frequencies between 2 and 2.5 GHz reveal an image rejection of 20 dB and a spur-free dynamic range of 107 dB/Hz/sup 2/3/.
Modulation of predator–prey interactions by the Allee effect

An Allee effect arising from density-dependent mating success can have significant impacts at the ecosystem level when considered in the context of predator–prey interactions. These are captured by a mathematical model for the exchange of biomass between a structured predator population (continuous weight distribution) and a resource. Because the predator’s mating success affects the amount of resources required for the production of offsprings and their future growth into mature organisms, it influences the flux of biomass between trophic levels. Under simple assumptions, the equations can be reduced to an equivalent unstructured predator–prey model in which the Allee effect modulates the predation rate: the mating probability multiplies the rate of predator growth as well as the rate of resource depletion. Implications of the Allee effect for the bifurcation structure and equilibrium densities are examined. The model is compared to a modified version in which the Allee effect instead modulates the assimilation efficiency, hence the mating probability does not appear in the dynamical equation for the resource density. Both models exhibit qualitatively similar dynamics. However, compared to the model in which the Allee effect modulates predation, the model in which the Allee effect modulates assimilation efficiency predicts (i) unrealistically inefficient resource assimilation when predator density is low, (ii) a higher risk of catastrophic extinction resulting from a change in the parameter controlling the strength of the Allee effect, and (iii) no possibility of an increase in population size when the density dependence is enhanced.
Kinetics of Oxidation of Ni Aluminide Exposed to Oxygen-Sulfur Atmospheres

As part of a development effort on nickel aluminides based on Ni3Al as structural materials for fossil energy applications, oxidation/sulfidation studies are being conducted at Argonne National Laboratory on materials that are being developed at Oak Ridge National Laboratory. Sheet samples of nickel aluminide, containing 23.5 at, % Al, 0.5 at. % Hf, and 0.2 at. % B were tested in an annealed condition and after preoxidation treatments. Continuous weight-change measurements were made at 875°C by a thermogravimetric technique in exposure atmospheres of air, a low-p02 gas mixture, and low-p02 gas mixtures with several levels of sulfur. getailed analyses of the corhosion product scale layers were conducted using a scanning electron microscope equipped with an energy dispersive x-ray analyzer and an electron microprobe. The air-exposed specimens developed predominantly nickel oxide; the specimen exposed to a low-p02 environment developed an aluminum oxide scale. As the sulfur content of the gas mixture increased, the alumina scale exhibited spallation and the alloy tended to form nickel sulfide as the reaction phase. The results indicated that the sulfidation reaction in nickel aluminide specimens (both bare and preoxidized) was determined by the rate of transport of nickel from the substrate through the scale to the gas/alumina scale interface, mechanical integrity of the scale, and the H2S concentration in the exposure environment.