cssi/SciSciGPT-SciSciNet huggingface dataset:
TRANSIENT HOLES IN THE ERYTHROCYTE MEMBRANE DURING HYPOTONIC HEMOLYSIS AND STABLE HOLES IN THE MEMBRANE AFTER LYSIS BY SAPONIN AND LYSOLECITHIN

Ferritin and colloidal gold were found to permeate human erythrocytes during rapid or gradual hypotonic hemolysis. Only hemolysed cells contained these particles; adjacent intact cells did not contain the tracers. Ferritin or gold added 3 min after the onset of hypotonic hemolysis did not permeate the ghost cells which had, therefore, become transiently permeable. By adding ferritin at various times after the onset of hemolysis, it was determined that for the majority of the cells the permeable state (or interval between the time of development and closure of membrane holes) existed only from about 15 to 25 sec after the onset of hemolysis. It was possible to fix the transient "holes" in the open position by adding glutaraldehyde only between 10 and 20 sec after the onset of hemolysis. The existence of such fixed holes was shown by the cell entry of ferritin and gold which were added to these prefixed cells. Membrane defects or discontinuities (of the order of 200–500 A wide) were observed only in prefixed cells which were permeated by ferritin subsequently added. Adjacent prefixed cells which did not become permeated by added ferritin did not reveal any membrane discontinuities. Glutaraldehyde does not per se induce or create such membrane defects since cells which had been fixed by glutaraldehyde before the 10-sec time point or after the 180-sec time point were never permeable to added ferritin, and the cell membranes never contained any defects. It was also observed that early in hemolysis (7–12 sec) a small bulge in one zone of the membrane often occurred. Ghost cells produced by holothurin A (a saponin) and fixed by glutaraldehyde became permeated by ferritin subsequently added, but no membrane discontinuities were seen. Ghosts produced by lysolecithin and fixed by glutaraldehyde also became permeated by subsequently added ferritin, and many membrane defects were seen here (about 300 A wide).
Filtrations for periodic modules over restricted Lie algebras

Periodic modules are modules which admit periodic projective resolutions. In this paper it is shown that under suitable conditions periodic modules over the restricted enveloping algebra of a graded restricted Lie algebra admit filtrations in terms of intermediate (Verma) modules. Moreover, using filtrations results about determining projectivity of modules by detecting projectivity upon restriction to certain subalgebras are given for graded Lie algebras.
Dynamic pushing strategies for dynamically stable mobile manipulators

This paper presents three effective manipulation strategies for wheeled, dynamically balancing robots with articulated links. By comparing these strategies through analysis, simulation and robot experiments, we show that contact placement and body posture have a significant impact on the robot's ability to accelerate and displace environment objects. Given object geometry and friction parameters we determine the most effective methods for utilizing wheel torque to perform non-prehensile manipulation.
Head injury pattern in children can help differentiate accidental from non-accidental trauma

Our aim was to define the radiographic findings that help differentiate abusive head trauma (AHT) from accidental head injury. Our trauma registry was queried for all children ≤5 years of age presenting with traumatic brain injury (TBI) from 1996–2011. Of 2,015 children with TBI, 71 % had accidental injury and 29 % had AHT. Children with AHT were more severely injured (ISS 22.1 vs 14.4; p < 0.0001) and had a higher mortality rate (15 vs 5 %; p < 0.0001). Patients with AHT had higher rates of diffuse axonal injury (14 vs 8 %; p < 0.0001) and subdural hemorrhage (76 vs 23 %; p < 0.0001). Children with accidental injury had higher rates of skull fractures (52 vs 21 %; p < 0.0001) and epidural hemorrhages (11 vs 3 %). AHT occurred in 29 % of children and resulted in increased mortality rates. These children had higher rates of subdural hemorrhages and diffuse axonal injury. Physicians initially evaluating injured children must maintain a high index of suspicion for abuse in those who present with subdural hematoma or diffuse axonal injury.
Regions of autumn Eurasian snow cover and associations with North American winter temperatures

The extent of snow cover over Eurasia during autumn has been shown to be influential in shaping atmospheric circulation over the Northern Hemisphere the following winter via the Arctic Oscillation (AO), North Atlantic Oscillation (NAO), and the Pacific/North American (PNA) teleconnections. Regions of Eurasian snow cover were derived from Principal Component Analysis and compared to winter temperatures across North America for 1967/1968–2007/2008, excluding 1969/1970 and 1971/1972. The score time series of each principal component was then compared to winter averages of the AO, NAO, and PNA indices in order to identify possible links in the snow-temperature relationship. Results showed that autumn snow cover from northern Scandinavia to the West Siberian Plain is most significantly associated with winter temperatures over the interior of North America. More (less) frequent snow cover over this region is related to lower (higher) winter temperatures over the interior of North America in January, extending to the eastern and southern United States in February. The greatest temperature response to anomalous snow cover occurred near the geographic centre of North America where winter temperature differences exceeded 5 °C. More (less) frequent autumn snow cover across the eastern Tibetan Plateau was associated with higher (lower) temperatures in the Great Basin and eastern Canada. Copyright © 2011 Royal Meteorological Society
Identidade e discurso em “Avenida Brasil”; “Falar, Ler e Escrever Português” e “Ponto de Encontro”

Este trabalho analisa tres livros-texto de portugues como segunda lingua, empregando metodos da Analise Critica do Discurso focados no conceito de identidade: Avenida Brasil 1 (1991), Falar, Ler, Escrever Portugues (1999) e Ponto de Encontro (2007). Discutimos (1) o conceito de linguagem, conhecimento e de aprendizagem de um idioma estrangeiro presentes no texto; (2) as relacoes de poder entre o emissor-emissario e no proprio texto; e (3) como o texto apresenta os conceitos de identidade, cultura e sociedade, o Brasil e o estrangeiro. Os resultados mostram que os tres livros empregam estrategias discursivas diferentes para seduzir o leitor e tratam de temas relacionados a ideologia, linguagem, o processo de aprendizagem linguistico e cultura. Eles mostram, assim, perspectivas muito diferentes das possibilidades discursivas em portugues como segunda lingua.
1,2,4,5-tetrazine based energetic materials

Abstract The synthesis and properties of several new energetic 1,2,4,5-tetrazine derivatives are described. These include energetic salts of 3,6-dihydrazino-1,2,4,5-tetrazine and several symmetrically and unsymmetrically substituted tetrazines with energetic substituents, in addition to a new nitro-tetrazine.
Regulation of calcium release is gated by calcium current, not gating charge, in cardiac myocytes

In skeletal muscle, intramembrane charge movement initiates the processes that lead to the release of calcium from the sarcoplasmic reticulum. In cardiac muscle, in contrast, the similarity of the voltage dependence of developed tension and intracellular calcium transients to that of calcium current suggests that the calcium current may gate the release of calcium. Nevertheless, a mechanism similar to that of skeletal muscle continues to be postulated for cardiac muscle. By using rapid exchange (20 to 50 milliseconds) of the extracellular solutions in rat ventricular myocytes in which the intracellular calcium transients or cell shortening were measured, it has now been shown that the influx of calcium through the calcium channel is a mandatory link in the processes that couple membrane depolarization to the release of calcium. Thus, intramembrane charge movement does not contribute to the release of calcium in heart muscle.
Heat capacity of carbon nanotubes

Abstract The low-temperature behavior of the heat capacity, CV, of carbon nanotubes is estimated in order to address the question: How small must nanotubes be for CV to be measureably different from that of bulk graphite? We predict that all single-walled tubes should have CV ∝ T at sufficiently low temperature, even if the tubes are semiconducting. The range of temperature and tube radii for which this is expected to be observable is shown to be well within current experimental constraints. Multi-walled tubes are also discussed.
Bad vibrations: new evidence on commons quality and localism at California’s surf breaks

This study extends prior empirical research on issues associated with the common-pool resource represented by California’s surf breaks by (1) expanding the test area to include all of the state’s surf breaks, (2) exploring additional aspects of surf break quality, (3) redefining “access” to the surf breaks by would-be users, and (4) re-examining linear restrictions present in prior empirical modeling. The results presented in this study are perhaps even more striking than those from prior research—indicating that marginal increases in surf break quality lead to relatively large increases in the probability of observing fierce localism at surf breaks. Results also indicate that localism is heightened along the surf breaks of Central California, an area previously unstudied. Although this study focuses on the relationship between surf break quality and localism, its findings offer greater understanding of the general importance of informal property rights protection of common-pool resources.
Explaining the success and failure of post-communist revolutions

Abstract Since 1999, the post-Communist states have seen a series of attempts to overthrow semi-authoritarian governments, with the successful attempts known as the “colored revolutions.” However, not all such attempts have succeeded. This paper seeks to explain the variation in outcomes. Most accounts have focused on the development of grass-roots activist movements. The central argument here is that elites, and in particular security services, play a much more significant role in these revolutions than has generally been appreciated. This hypothesis is elaborated through a threshold model of protest, in which the central question is whether protests achieve a “tipping point” that makes them continue to grow larger until success is inevitable. The actions of elites, it is argued, play a decisive role in whether mass protests reach a tipping point. The argument is examined through a paired comparison of two failed attempts to overthrow governments through street protests (Serbia 1996–1997 and Ukraine 2001) with two successful cases (Serbia 1999 and Ukraine 2004). By studying cases with variation on the dependent variable, this paper seeks to improve the empirical and methodological basis of research on post-communist revolutions.
Two-field versus three-field irradiation technique in the postoperative treatment of head-and-neck cancer

Purpose: We have increasingly used a two-field noncoplanar “caudal tilt” technique (CTT) for irradiating postlaryngectomy and pharyngectomy patients to avoid matchline problems that can be encountered with the classic three-field head-and-neck radiation technique (3FT). This report compares the clinical outcomes of patients treated with postoperative radiation (PORT) using either 3FT or CTT. Methods and Materials: We conducted a retrospective review of the medical records of all patients with laryngeal or hypopharyngeal cancers consecutively treated with PORT between 1997 and 2002. Three-dimensional dosimetric planning was carried out for all patients. Results: Of 91 patients, 39 were treated with 3FT and 52 with CTT. The median follow-up was 34 months. Estimated rates of 2-year locoregional control, disease-free survival, and overall survival for patients treated with 3FT and CTT were, respectively, 92% and 85% ( p = 0.241), 62% and 55% ( p = 0.497), and 77% and 72% ( p = 0.616). There were no significant differences in the incidence of acute or late side effects in the two groups. Conclusions: “Caudal tilt” technique is often used as an alternative to 3FT for postoperative radiotherapy in cases of greater medical and technical complexity. Despite its use in more challenging cases, CTT provides similar long-term clinical outcomes compared with standard 3FT, when computerized three-dimensional dosimetry is used to assure adequate dosimetry throughout the treated volume.
Education: Barrier or Boon to Changing Occupational Roles of Women?

Traditional educational institutions have contributed to occupational stratification by sex, but they have the potential to play a primary role in the sexual integration of the occupational world. Research on the ontogeny of the occupational aspirations of young women is reviewed, and three major sex-biased educational practices which may be contributing to the restriction of these aspirations are discussed: textbooks and instructional materials, differential curricula for males and females, and vocational counseling and testing. Recent legislation is evaluated for its usefulness in modifying each of these sex biases. A conceptual framework is suggested for designing policy relevant research which is aimed at maximizing women's occupational potential.
A sequence defined by M-sequences

Abstract In this note we consider the sequence whose n th term is the number of M -sequences of length n . We show that the n th term of this sequence is bounded above by the n th Fibonacci number and bounded below by the number of integer partitions of n into distinct parts.
Glu-Leu-Arg-Negative CXC Chemokine Interferon γ Inducible Protein-9 As a Mediator of Epidermal–Dermal Communication During Wound Repair

Normal wound healing is a complex, highly regulated dynamic process that requires co-ordinate responses of both epidermal and dermal compartments. To accomplish the healing process several growth factors, chemokines, and matrix elements signal both cell proliferation and migration during the inflammatory and reparative phases and limit these responses during the remodeling phase. We have found that the Glu-Leu-Arg-negative CXC chemokines interferon γ inducible protein 10, monokine induced by interferon γ, and platelet factor 4, limit fibroblast responsiveness to growth factors, but the functioning of these factors in wound healing remains uncertain. We hypothesized that the keratinocyte-derived member of this Glu-Leu-Arg-negative CXC family, interferon γ inducible protein 9 (IP-9) CXCL11 (also known as I-TAC, β-R1, and H-174) signals to the dermal compartment to synchronize the re-epithelialization process. Interferon γ inducible protein 9 was produced after mechanical wounding of a keratinocyte monolayer, suggesting for the first time that this could be a wound response factor. Interferon γ inducible protein 9 limited epidermal growth factor (EGF)-induced fibroblast motility (57±7%) by the same protein kinase A (KA)-mediated inhibition of calpain activation and cell de-adhesion as described for interferon γ inducible protein 10. Surprisingly, interferon γ inducible protein 9 enhanced growth factor-induced motility in undifferentiated keratinocytes (137±19%) as determined in a two-dimensional in vitro wound healing assay, and interferon γ inducible protein 9 alone promoted motility in undifferentiated keratinocytes (49±10% of epidermal growth factor-induced motility). A stimulated keratinocyte/target cell coculture system revealed that interferon γ inducible protein 9 acts as a soluble keratinocyte-derived paracrine factor for both fibroblasts and keratinocytes. Further, we found that in both fibroblasts and undifferentiated keratinocytes, interferon γ inducible protein 9 exerted its action through modulation of a cytosolic protease, calpain. Interestingly, interferon γ inducible protein 9 increased calpain activity in undifferentiated keratinocytes, whereas the same chemokine inhibited the calpain activity in fibroblasts. This provides for a model whereby redifferentiated basal keratinocytes could limit fibroblast repopulation of the dermis underlying healed wounds while simultaneously promoting re-epithelialization of the remaining provisional wound.
Development of a trpE promoter-strength measuring system and its use in comparison of the trpEDCBA, trpR and aroH promoters.

Abstract An expression System was developed for measuring in vivo promoter strength at the single copy level and this System was used to compare the trp , aroH and trpR promoters. This System employs trpE enzyme activity as a measure of promoter strength and lacZ expression for internal copy number reference. Promoter-containing fragments are inserted into a cloning vector and subsequently recombined on to phage lambda by genetic exchange. Single lysogens are then prepared and used in promoter-strength analyses. The strength of several promoters was determined using this system. Among the promoters tested, the Escherichia coli trpEDCBA promoter was the strongest; it was four times more active than the lacUV5 promoter and about ten times stronger than the trpR and aroH promoters. To validate measurement of trpE enzyme activity as an indicator of promoter strength, trpE enzyme activity was compared with the level of trpE mRNA. There was excellent correspondence between the two, suggesting that with this system trpE enzyme activity accurately reflects promoter strength. We also examined a homologous promoter-strength measuring system in which the promoter-cloning plasmid lacked a 104 base-pair DNA spacer that was present immediately downstream from the promoter-cloning site in our preferred system. We found that the spacer was essential; the transcribed region accompanying a cloned promoter apparently affected trpE translational efficiency and/or trpE mRNA stability.
GENETIC HOMOLOGY OF WINE YEASTS WITH SACCHAROMYCES CEREVISIAE

Two wine yeasts (a Montrachet and a Burgundy) were shown to be homothallic diploids, chromosomally homologous to heterothallic, laboratory-bred strains of S. cerevisiae and to a homothallic diploid strain of S. uvarum. Hybrids between the two wine yeasts, and between the two yeasts and selected non-commercial yeasts are stable and produce an abundance of viable ascospores. The strains are amenable to genetic analysis and modification of commercially important characteristics. The five other wine yeasts examined are not immediately amenable to genetic analysis. Two would not sporulate and three sporulated at low frequency and produced few viable ascospores.
Variable threshold discrimination in a photon-imaging detector.

The photon statistics of a particular photon-imaging detector are studied, and the conditional probability of photon counts in the output given a certain number of counts in an associated reference channel is derived. This result is applied in a variable level discrimination technique which significantly reduces detection errors approaching the ideal limit. These results can be applied to other photon-limited detectors with nonideal pulse height distributions.
An ethnobotany of Western Cape Rasta bush medicine.

Abstract Aims of this study This descriptive ethnobiological research is the first documentation of the materials utilized in the pharmacopeia of a novel group of herbalists, Rasta bush doctors, found in the botanically diverse Western Cape of South Africa. This article suggests that medicinal plants used by bush doctors unite the disparate ethnomedicines found in South Africa. Materials and methods Ethnospecies name and parts used were recorded during detailed inventories of 39 bush doctors. Collection of voucher specimens for botanical identification occurred in 15 locations. Herbal remedies were classified into use categories and were compared to historical ethnobotanical literature to ascertain previous cultural affiliations. Results There were 205 ethnospecies found in the Rastafari ethnobiology, 181 were used medicinally. Ethnospecies belong to 71 plant families and 71% belonged to six plant families: Rutaceae (13), Asteraceae (13), Apiaceae (9), Lamiaceae (8), Fabaceae (8), and Euphorbiaceae (7). The majority of remedies (49%) were foliage. Medicinal plants treated over 30 ailments including: gastrointestinal symptoms (11%), urogential complaints (11%), skin ailments (9%), and cardiovascular diseases (8%). Bush doctors appropriated remedies traditionally important to Zulu, KhoiSan, European and Xhosa healing traditions. Novel plants and plant utilization were noted for 22 plant species. Conclusions Use of previously undocumented plant materials as medicinals denote distinct local knowledge including novel Rastafarian utilization of herbs for spiritual and ritual purposes. The range of the largely herbaceous pharmacopeia is narrow compared to the region's highly biodiverse materials and historical records of medicinal use. Bush doctors’ experimentation with known herbal remedies illustrates a striking level of cross-cultural adaptation. This syncretic pharmacopeia reflects the cultural diversity of Southern Africa, drawing upon recent invasive species, European influence and traditional herbs used by the KhoiSan, Zulu and Xhosa peoples.
Calculation of the capture of negative pions in light elements and comparison with experiments pertaining to cancer radiotherapy

Abstract Reactions resulting from the capture of π− mesons in carbon, nitrogen, oxygen, and aluminum have been studied using a Monte Carlo intranuclear-cascade model. The calculation predicts the multiplicities of the particles emitted following π− capture and the residual nuclei remaining after the reaction. The energy distributions of the emitted particles and the residual nuclei have also been determined. The results of the calculation have been compared with experiments investigating the feasibility of the use of π− mesons in cancer radiotherapy, and reasonable agreement has been obtained.
Yearly Changes in the Body Composition and Muscular Strength of High School Wrestlers.

Abstract The purpose of this investigation was to determine the yearly changes in body composition as well as absolute and relative isokinetic forearm flexion and extension strength of high school wrestlers. Evaluations of body composition (underwater weighing) were performed on 27 high school wrestlers prior to three consecutive seasons. In addition, isokinetic forearm flexion and extension strength values at 180°/s (Cybex II) were available for 20 of the subjects. The mean ages at the times of laboratory testing were 15.5 (± .5), 16.5 (± .5), and 17.5 (± .5) years. Repeated measures ANOVA or ANCOVA with Tukey post-hoc comparisons were used to locate significant (p<.05) differences across age for height, body weight, relative fat, body density, fat weight, fat-free weight, absolute muscular strength, and muscular strength covaried for body weight and fat-free weight. There were yearly increases in all variables except fat weight, forearm flexion covaried for fat-free weight and forearm extension covaried...
Issues in the design of a randomized noninferiority clinical trial of telemental health psychotherapy for rural combat veterans with PTSD

This methodological article provides a description of the design, methods, and rationale of the first prospective, noninferiority designed randomized clinical trial evaluating the clinical and cost implications of delivering an evidence-based cognitive-behavioral group intervention specifically treating posttraumatic stress disorder (PTSD) with a trauma-focused intervention via video teleconferencing (VTC). PTSD is a prevalent mental health problem found among returning Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) military populations. These returning military personnel often live in rural areas and therefore have limited access to care and specialized psychological treatments. In the field of mental health, telemental health (TMH) technology has introduced a potential solution to the persistent problem of access to care in remote areas. This study is enrolling approximately 126 returning veterans with current combat-related PTSD who are receiving services through the Veteran Administration (VA) mental health care clinics on 4 Hawaiian Islands. Cognitive Processing Therapy (CPT), an empirically supported manualized treatment for PTSD, is being delivered across 9 cohorts. Participants are assigned to either the experimental VTC condition or the in-person control condition. Assessments measuring clinical, process, and cost outcomes are being conducted at baseline, mid-treatment, post-treatment, and 3 and 6 months post-treatment. The study employs a noninferiority design to determine if the group treatment delivered via VTC is as good as the traditional in-person modality. In addition, a cost analysis will be performed in order to compare the cost of the 2 modalities. Novel aspects of this trial and specific challenges are discussed.
Improved calculation on the isotope effect in dissociative electron attachment to acetylene

We performed nuclear dynamics calculations on ${\text{C}}_{2}{\text{H}}_{2}$ and ${\text{C}}_{2}{\text{D}}_{2}$ to study the isotope effect in dissociative electron attachment (DEA). Our previous calculations at 0 K led to a ratio ${\ensuremath{\sigma}}_{0\ensuremath{\rightarrow}\text{DEA}}^{({\text{C}}_{2}{\text{H}}^{\ensuremath{-}})}/{\ensuremath{\sigma}}_{0\ensuremath{\rightarrow}\text{DEA}}^{({\text{C}}_{2}{\text{D}}^{\ensuremath{-}})}$ of about 28.9 which is about a factor of 2 higher than recent experimental results. This discrepancy was attributed to the contribution of higher vibrational modes in the yield of the anion fragments. We included the four lowest bending vibrational states presenting nonvanishing populations at the experiment temperature of $T=333\text{ }\text{K}$. The resulting ratio is found to be 17.9 which is in closer agreement with the measured value.
The Genomic System of Classification as a Guide to Intergeneric Hybridization with the Perennial Triticeae

Of the approximately 325 species in the tribe Triticeae (= Hordeeae), about 250 are perennials that include many of the world’s important forage grasses. Although more than 75% of the species in the Triticeae are perennials, they have received far less attention from cytogeneticists and plant breeders than have the annuals, which include three major cereal crops--wheat, barley, and rye. In addition to being important in their own right as forages, the perennials form a vast genetic reservoir that might be used to improve the annual cereals.
The absolute structure of ptilosarcenone 2.5-hydrate, a diterpenoid briarane from the orange sea pen Ptilosarcus gurneyi (Gray).

In the title compound, C24H29ClO8·2.5H2O, which contains two organic mol­ecules (A and B) and five heavily disordered water mol­ecules in the asymmetric unit, the γ-lactone ring and the cyclo­hexenone ring are both trans-fused to the central cyclo­decene ring. The cyclehexenone ring features an α,β-unsaturated ketone with torsion angles between the conjugated carbonyl and alkene bonds of 0.6 (3) and 7.4 (4)° for mol­ecules A and B, respectively. The ptilosarcenone torsion angles between conjugated alkene bonds are 56.2 (5) and 55.4 (6)° for A and B, respectively. In the crystal, the components are linked by O—H⋯O hydrogen bonds. The absolute configuration of ptilosarcenone was determined unambiguously and exhibits similar absolute stereochemistry to that found in the crystal structures of other octocoralline briaranes.
Detection of tumor necrosis factor induced nuclear damage with p-phenylenediamine.

Abstract A simple technique has been used to observe the effects of rTNFα on nuclear morphology. Using the intercalating dye p -phenylenediamine to stain nuclei, we detected TNFα-induced nuclear alterations which characteristically occur during apoptosis in the TNFα sensitive U937 cell line. Nuclear alterations were visible prior to the loss of plasma membrane integrity and subsequent cell death. A subclone of U937 cells was isolated in which TNFα failed to alter either cell viability or nuclear morphology. TNFα resistant U937 cells, however, retained the ability to bind, internalize and degrade TNFα. These results suggest that nuclear damage induced by TNFα in sensitive U937 cells occurs early and precedes cell death as measured by dye exclusion assays. Staining cells with p -phynylenediamine and visualization with a 520 nm fluorescence filter provides a rapid and simple method to monitor apoptotic cell death.
Estimation of contemporaneous mortality factors

We present methods for solving and making statistical inferences about marginal attack rates based on observed death rates for contemporaneous mortality factors. The general method of solution involves solving a system of nonlinear equations which depend in part on competition coefficients that express the outcome when more than one agent attacks the same host individual. For two factors, we present a detailed analysis of the effect of varying this competition coefficient. Statistical inferences are illustrated using standard large sample approximations (the delta method) and the bootstrap, which is a resampling technique. We also extend the results to allow inferences fork-values.
Some analytical results for the initial phase of bottom slamming

Abstract The deformation of boat hull bottom panels during the initial phase of slamming is studied analytically using a linear elastic Euler–Bernoulli beam as a representation of the cross section of a bottom panel. The slamming pressure is modeled as a high-intensity peak followed by a lower constant pressure, traveling at constant speed along the beam. The problem is solved using a Fourier sine integral transformation in space and a Laplace–Carson integral transformation in time. Deflection and bending moment as functions of time and position for different speeds, bending stiffnesses, etc. are given. In particular the effect of slamming load traveling speed on structural response of the simplified bottom structure is investigated. It is found that rather large deflections and bending moments are encountered at certain speeds of the pressure, which suggests that bottom panels may benefit from tailoring their stiffness and mass properties such that loads are reduced. This would vary with boat particulars and operation (deadrise angle, mass, speed, sea state, etc). The importance of the high-intensity pressure peak often encountered during slamming is also studied. It is seen that for relatively slow moving slamming loads the pressure peak has little influence. However, for faster moving loads its influence can be significant.
The preejection period of the fetal cardiac cycle. I. Umbilical cord occlusions.

Abstract The preejection period (PEP) of the fetal cardiac cycle was studied in the chronically instrumented fetal lamb. A specially constructed device permitted the occlusion of either both umbilical veins, or of both umbilical arteries, or of the total umbilical cord. A prolongation of the PEP together with an increase in blood pressure was a consistent finding during any type of cord occlusion. In poorly oxygenated fetal lambs a two-step increase in the duration of the PEP was observed during the occlusion. It was accompanied by a simultaneous two-step increase in fetal arterial blood pressure. A correlation was found between the steady-state fetal p O 2 before the occlusion and the increase in fetal arterial diastolic blood pressure during the blockade of the umbilical circulation. During occlusion the main determining factors of the PEP prolongation appear to be the increase in afterload and the decrease in preload of the fetal heart. The second step in the prolongation of the PEP during the occlusions in poorly oxygenated fetal lambs is attributed to a chemoreceptor-induced reflex, resulting in a redistribution of cardiac output in the fetal lamb.
People, words, and perceptions: a phenomenological investigation of textuality

Two experiments investigated how textual factors influence the perception of bibliographical records. Subjects in the first experiment browsed indexes for the subject descriptor associated with the displayed record. Results showed that topical and broader descriptors are matched to records more easily than narrower descriptors. In the second experiment, subjects ranked the relevance of descriptors for a bibliographic record. The interaction of three textual factors are reported: (a) semantic distance; (b) direction up or down a generic tree of descriptors; and (c) term overlap. Both experiments found that relevance perceptions degraded systematically with semantic distance, but the rate of degradation was different for top and bottom records. Term overlap modified these effects
The calculation of polyvacancy concentrations in rigid disk and hard sphere solids using cell cluster techniques

Abstract Formal expressions for the concentrations of monovacancies and for equilibrium constants for higher order vacancies are derived for v -dimensional hard sphere solids near close packing. The concentration of monovacancies is found to be P 1.1 = K 1.1 exp ⁡ [ D – v ] exp ⁡ [ – v / ( т – 1 ) ] where P 1.1 is the fraction of lattice sites occupied by monovacancies, K 1.1 is a ratio of free volumes, τ is the reduced volume for the system and D is a constant due to the curvature of the accessible regions of the spheres. Cell cluster theory is discussed and used to evaluate numerically expressions for the concentrations of mono- and divacancies in the f.c.c. and h.c.p. lattices of hard spheres. The significance of the results is discussed in relation to cell cluster theory and experimental results for the concentration of, and free energy of formation of vacancies.
Role of probabilistic analysis in integrity assessments of reactor pressure vessels exposed to pressurized thermal-shock conditions

Abstract In recent years, probabilistic analyses have been playing an increasing role in safety assessments for nuclear power plants (NPPs) in the USA. An important example is the treatment of integrity analyses for the primary reactor pressure vessel (RPV) when it is exposed to pressurized thermal-shock (PTS) events. The U.S. Nuclear Regulatory Commission’s (NRC) approach to ensuring PTS integrity over the RPV lifetime has been to establish limits that ensure that the likelihood of through-wall-crack (TWC) development is kept below a prescribed very low level. The key elements for the probabilistic fracture mechanics (PFM) analysis package include thermal-hydraulic analysis input, neutron exposure models, embrittlement models for RPV steels, representations of fracture properties data, flaw characterization models, PFM models, and computational computer codes. The state of knowledge that existed when the NRC initially formulated the PTS rule in the 1980s necessitated that the rule and its technical bases use conservative treatment of parameters and models. Advancements made in the ensuing 20 years have motivated the NRC to undertake a comprehensive update of these technical bases to support potential revisions to the rule. The current status of the key technical elements has now been established, and an updated PFM methodology is being drafted and used for preliminary analyses of three U.S. PWRs. The frequencies of vessel failure predicted by these analyses have been compared with those calculated under the early PTS methodology and are encouraging that a revision to the PTS rule may be forthcoming. Because the PFM calculations utilize a series of deterministic LEFM fracture analyses, it is important to know the degree to which the LEFM methods are applicable to the analysis of thick-wall vessels. U.S. efforts to establish this applicability have been extensive and included a significant number of fracture experiments using large-scale vessels to validate analysis methods and demonstrate margins within design codes. This paper includes a summary of results from several of those key experiments.
Respiratory Syncytial Virus Hospitalizations Among American Indian and Alaska Native Infants and the General United States Infant Population

Objective. To determine the burden of respiratory syncytial virus (RSV) disease among American Indian (AI) and Alaska Native (AN) infants, by examining RSV-associated hospitalizations. Methods. Infant hospitalizations from 1997 through 2001 with RSV listed as a diagnosis were selected by using Indian Health Service/tribal hospital discharge data for AIs/ANs and National Hospital Discharge Survey data for the general US population. Results. In 2000–2001, RSV disease was listed as a diagnosis for 14.4% of all AI/AN infant hospitalizations, with bronchiolitis attributable to RSV infection (12.2%) being among the top 5 listed diagnoses. The rate of RSV-specific hospitalizations was 34.4 hospitalizations per 1000 infants for AI/AN infants and 27.4 hospitalizations per 1000 births for the general US infant population. The hospitalization rates for AI/AN infants living in the Alaska and Southwest regions (70.9 and 48.2 hospitalizations per 1000 infants, respectively) were much higher than the overall rate for US infants. Conclusions. RSV infection is one of the leading causes of hospitalization among all infants in the United States, and AI/AN infants living in the Southwest and Alaska regions are at especially high risk for hospitalizations associated with RSV infection. Development of vaccines, antiviral agents, and other strategies to prevent RSV disease could yield substantial public health benefits.
DRiBAC: Fine-grained dynamic role interaction access control using ontology

Multiagent systems are characterized by enriched interactions among agents, which have dynamic and autonomous behavior, towards achieving some common goals. Such interactions involve accessing an agent's resources and functionalities by other agents. It is critical that such interactions are secure and agents engage in only authorized interactions based on their roles. In this paper, we propose a fine-grained Dynamic Role Interaction Access Control (DRiBAC) model to support exclusive authorization for agents that need to engage in interactions with other agents by dynamic assignments of roles and permissions and their activations. We extend an earlier proposed RiBAC model with the notion of role interaction and interaction assignment and context-aware constraints. To capture the model and its context, and to support semantic reasoning of DRiBAC policies, we propose DRiBAC ontology and illustrate its use on an example online tutoring system.
Implications of long-term changes in valley geomorphology on the behavior of small-volume pyroclastic flows

Abstract Stratigraphic mapping in the lower 3km of the Vazcun Valley on the NE flank of Volcan Tungurahua (Ecuador) provides insight into the effects of long-term geomorphic changes on pyroclastic flow behavior. Exposures of deposits in the Vazcun Valley record activity over the last 2000years, during which time significant changes in the geomorphology of the valley have occurred. Two sets of terraces are present in the lower 2–3km of the valley, the older of which grades into a small debris fan at the mouth of the valley. Each terrace formed during a period of frequent activity that was separated by a long period of quiescence during which the Rio Vazcun eroded a channel as deep as 40m reaching the previous base level. The pyroclastic flows from historical eruptions appear to have been largely contained within the channel that is cut through the higher terraces and debris fan. Their surface forms the lower terrace located upstream from the head of the debris fan. Thin pyroclastic deposits exposed within the city of Banos are mostly related to ash cloud surges that detached from the main flows as they slowed down within the channel. The lower reach of the present channel of the Rio Vazcun is very sinuous and deeply incised into the two sets of terraces. The winding channel would severely impede the mobility of future pyroclastic flows resulting in the deposition of thick deposits. Detachment of an overriding ash cloud surge could also occur in this region. Such a surge could be more likely to surmount the channel banks and travel over the surface of the terraces and debris for up to several kilometers from the channel.
Regulation of Interferon-Stimulated Genes in Peripheral Blood Leukocytes in Pregnant and Bred, Nonpregnant Dairy Cows

In ruminants, pregnancy results in up-regulation of a large number of IFN-stimulated genes (ISG) in the uterus. Recently, one of these genes was also shown to increase in peripheral blood leukocytes (PBL) during early pregnancy in sheep. Our working hypothesis is that conceptus signaling activates maternal gene expression in PBL in dairy cattle. The objectives of this study were to characterize ISG expression in PBL from pregnant (n = 20) and bred, nonpregnant (n = 30) dairy cows. Steady-state levels of mRNA for Mx1, Mx2, beta2-microglobulin, ISG-15, IFN regulatory factor-1, and IFN regulatory factor-2 were quantified. Holstein cows were synchronized to estrus and artificially inseminated (d 0). Blood samples were collected (coccygeal venipuncture) on d 0 and 16, 18, and 20 d after insemination for progesterone analysis and PBL isolation. Pregnancy was confirmed by transrectal ultrasonography at approximately 40 d after breeding. A status x day interaction was detected for Mx1, Mx2, and ISG-15 gene expression. When analyzed within day, levels of mRNA for ISG-15 and Mx1 were greater in pregnant compared with bred, nonpregnant cows on d 18 and 20, respectively. Expression of the Mx2 gene increased in the pregnant group compared with bred, nonpregnant cows on d 16, 18, and 20 after insemination. beta2-Microglobulin, IFN regulatory factor-1, and IFN regulatory factor-2 were not different between groups. The results clearly indicated that components of the innate immune response are activated in PBL during the period of pregnancy recognition and early embryo signaling. The physiological implications of these changes on maternal immune function are as yet unknown; however, they do provide a unique opportunity to identify bred, nonpregnant, cows 18 d after insemination in dairy cattle.
Primary myopathy and accumulation of PrPSc-like molecules in peripheral tissues of transgenic mice expressing a prion protein insertional mutation.

Abstract A nine-octapeptide insertional mutation in the prion protein (PrP) gene is associated with an inherited variant of Creutzfeldt–Jakob disease in humans. Transgenic mice that express the mouse PrP homologue of this mutation (designated PG14) under control of a PrP promoter display a progressive neurological disorder characterized by ataxia, apoptosis of cerebellar granule cells, and accumulation in the brain of mutant PrP molecules that display the biochemical hallmarks of PrPSc, the pathogenic isoform of PrP. In this report, we have investigated the expression of PG14 PrP in the peripheral tissues of these mice. We found highest levels of mutant PrP in the brain and spinal cord, intermediate levels in skeletal muscle, heart, and testis and low levels in kidney, lung, spleen, intestine, and stomach. Up to 70% of the PG14 PrP expressed in peripheral tissues was detergent-insoluble, and digestion with low concentrations of proteinase K yielded a PrP 27–30 fragment. These results suggest that the mutant protein was converted to a physical state reminiscent of PrPSc, although its infectivity remains to be determined. Histological analysis of skeletal muscle, one of the peripheral tissues with the highest level of PG14 PrP, revealed features indicative of a progressive, primary myopathy, including central nuclei, necrotic and regenerating fibers, and variable fiber size. These results indicate that the PG14 mutation structurally alters the protein in a way that promotes conversion to a PrPSc-like state, regardless of the tissue context, and suggest that accumulation of PrPSc can have deleterious effects on skeletal muscle cells as well as on neurons.
The Significance of William Osler's Museum Specimens of Aortic Aneurysms

ir William Osler developed his clinical acumen from a base of almost 1,000 autopsies which he performed, largely at the Montreal General Hospital.' He utilized the material from the autopsies, both clinical protocols and morphologic material, for a variety of purposes, including his museum of pathology, teaching, presentations at meetings of medical societies, his textbook, and many publications in journal^.^ Specimens prepared by Osler for his museum reflect in large part the diseases in which he had the greatest interest. Included are 11 specimens of aortic aneurysms, which are still in existence in the Pathology Institute of McGill University, Montreal. They are equal in number and quality to those specimens of Osler's other major interest, endocarditi~.~ A review of the specimens and related protocols of autopsies and of the publications by Osler has highlighted many aspects of his professional exper
Holographic implementation of a fully connected neural network

A holographic implementation of a fully connected neural network is presented. This model has a simple structure and is relatively easy to implement, and its operating principles and characteristics can be extended to other types of networks, since any architecture can be considered as a fully connected network with some of its connections missing. The basic principles of the fully connected network are reviewed. The optical implementation of the network is presented. Experimental results which demonstrate its ability to recognize stored images are given, and its performance and analysis are discussed based on a proposed model for the system. Special attention is focused on the dynamics of the feedback loop and the tradeoff between distortion tolerance and image-recognition capability of the associative memory. >
Crystallization and metastable phase transformations of zeolite ZSM-5 in the (TPA)2ONa2OK2OAl2O3SiO2H2O system

Abstract Zeolite ZSM-5 was synthesized as the only crystalline phase from Na-TPA, and for the first time from the K-TPA, and Na,K-TPA mixed cation systems. As the organic cation/ alkali metal cation ratio was decreased in the reaction mixture, metastable phases were found to coexist with ZSM-5. These were an “analcime-like” phase, and a “mordenite” phase in the Na-TPA system, and a “harmotome-like” phase in the K-TPA system. An isothermal metastable phase transformation diagram was developed for the Na-TPA system. A “gismondine-like” phase was added to the metastable phases coexisting with ZSM-5 and the crystallization sequence, mordenite, ZSM-5, analcime was found to change to gismondine, mordenite, ZSM-5, analcime with the addition of alkali metal salts to the reaction mixture. The “apparent activation energies” obtained for ZSM-5 were 25.57 and 19.41 kcal/gmole for nucleation and crystallization, respectively. The synthesis system could be modified as a result of the cation replacements and the exploratory runs with salt additions, to result in pronounced changes in the morphology, i.e., either to yield larger single crystals or crystal aggregates, desired for the commercial applications.
A Doppler Radar Emulator with an Application to the Detectability of Tornadic Signatures

Abstract A Doppler radar emulator was developed to simulate the expected mean returns from scanning radar, including pulse-to-pulse variability associated with changes in viewing angle and atmospheric structure. Based on the user’s configuration, the emulator samples the numerical simulation output to produce simulated returned power, equivalent radar reflectivity, Doppler velocity, and Doppler spectrum width. The emulator is used to evaluate the impact of azimuthal over- and undersampling, gate spacing, velocity and range aliasing, antenna beamwidth and sidelobes, nonstandard (anomalous) pulse propagation, and wavelength-dependent Rayleigh attenuation on features of interest. As an example, the emulator is used to evaluate the detection of the circulation associated with a tornado simulated within a supercell thunderstorm by the Advanced Regional Prediction System (ARPS). Several metrics for tornado intensity are examined, including peak Doppler velocity and axisymmetric vorticity, to determine the degra...