cssi/SciSciGPT-SciSciNet huggingface dataset:
Prostaglandin production by mouse fibrosarcoma cells in culture: inhibition by indomethacin and aspirin.

Abstract Five clonal strains of mouse tumor cells (HSDM1) synthesize and secrete large quantities (0.70-2.0 μg/mg cell protein/24 hr) of prostaglandin E2. Five lines of control cells did not synthesize significant amounts of prostaglandins. HSDM1 cells produce prostaglandin E2 during both the logarithmic and stationary phases of the cell growth cycle. Prostaglandin production was inhibited by aspirin-like drugs; for example, 50% inhibition was obtained with as little as 3 × 10−9 M indomethacin. We conclude that the HSDM1 cell system will serve as a useful model system to study prostaglandin synthesis and secretion.
The learning curve and sentinel node biopsy.

Abstract Background: The ability of sentinel node biopsy (SNB) to replace axillary node dissection for accurate breast cancer staging is absolutely dependent on the consistent and accurate determination and removal of the “true” sentinel node. There are a wide variety of variables that affect the ability of the physician to achieve this goal. One important and potentially controllable variable is physician training and competence to employ the available techniques successfully. There is a large diversity of opinion regarding the minimum number of cases required under supervision prior to independent utilization of the technique but there are data to support at least 20 cases done in conjunction with axillary dissection or under direct supervision. Methods: Data from single institution and multicenter trials are reviewed and the learning curves are described. An overview of surgical education methods, testing, and credentialing is also addressed. Results: A review of single institution series show that the false negative rate and identification rates vary considerably. In all cases where authors published a second series success rate improved compared with their initial series. Of the four multicenter trials only two can provide reliable learning curves and these have shown a decrease in the false negative rate to ≤5% after 20 to 30 procedures are performed. Conclusions: There are data to show that there is a definite learning curve for SNB that cannot be ignored. It is possible that other factors, (ie, a skin injection with technetium-99, Sappeys plexus injection, and mentoring) could decrease this learning curve but until compelling evidence to suggest otherwise is available, surgeons should obtain a minimum experience of 20 cases.
Nonstandard (non-σ-additive) probabilities in algebraic quantum field theory

Traditionally, physicists deduce the observational (physical) meaning of probabilistic predictions from the implicit assumption that thewell-defined events whose probabilities are 0 never occur. For example, the conclusion that in a potentially infinite sequence of identical experiments with probability 0.5 (like coin tossing) the frequency of heads tends to 0.5 follows from the theorem that sequences for which the frequencies do not tend to 0.5 occur with probability 0. Similarly, the conclusion that in quantum mechanics, measuring a quantity always results in a number from its spectrum is justified by the fact that the probability of getting a number outside the spectrum is 0. In the mid-60s, a consistent formalization of this assumption was proposed by Kolmogorov and Martin-Lof, who defined arandom element of a probability space as an element that does not belong to any definable set of probability 0 (definable in some reasonable sense). This formalization is based on the fact that traditional probability measures are σ-additive, i.e., that the union of countably many sets of probability 0 has measure 0. In quantum mechanics with infinitely many degrees of freedom (e.g., in quantum field theory) and in statistical physics one must often consider non-σ-additive measures, for which the Martin-Lof's definition does not apply. Many such measures can be defined as “limits” of standard probability distributions. In this paper, we formalize the notion of a random element for such finitely-additive probability measures, and thus explain the observational (physical) meaning of such probabilities.
Phototoxicity testing of fragrance raw materials.

Abstract Of 160 fragrance raw materials tested for phototoxicity by a procedure involving topical application of the test agents to the skin of hairless mice and miniature swine, followed by exposure of the skin either to simulated sunlight or to near-ultraviolet light (UV-A), 21 elicited a phototoxic response. Of these, 20 were members of the botanical families Rutaceae or Umbelliferae; the single exception was from the family Verbenaceae. Several selected materials were tested, in sunlight and under three laboratory light sources, on the skin of mouse, man and miniature swine. Mouse skin was the most sensitive, reactions in human and swine skin being qualitatively and quantitatively similar.
Size-Dependent Methanol Electro-oxidation Activity of Pt Nanoparticles with Different Shapes

We report a comparative electrochemical investigation of size-dependent methanol electro-oxidation activity on cubic vs. octahedral/tetrahedral Pt nanoparticles. The size range for the former was 9.5 nm to 5.6 nm to 4.5 nm and for the latter was 9.7 nm to 6.0 nm to 5.0 nm. Different trends were observed: the methanol activity increased as the nanoparticle size decreased on the cubic Pt nanoparticles but decreased on the octahedral/tetrahedral Pt nanoparticles. Although the presence of residual polyvinylpyrrolidone that was used as stabilizing ligand during the nanoparticles synthesis did complicate the mechanistic understanding of the observed trends, these observations nonetheless highlighted the fundamental and practical importance and the necessity of investigating and understanding, in a controllable fashion, the orientational sensitivity of catalytic activity at nanoscale in conjunction with size.
Vacuum-ultraviolet spectral-irradiance calibrations: method and applications

A method to determine the spectral irradiance of a radiation source in the vacuum ultraviolet through the use of recently developed spectral-radiance standards is described. The method has been applied between 138 and 310 nm, and the spectral irradiances of several different light sources have been measured on an absolute scale with estimated uncertainties less than 10%.
Synthesis of fac-[FeII(CN)(CO)3I2]− and chemistry of the fac-[FeII(CN)x(CO)3I(3 − x)]− series (x = 1–3)

Abstract Whole series of fac- [Fe II (CN) x (CO) 3 I (3 − x ) ] − ( x = 1–3) generated by stepwise replacement of iodide from fac- [Fe II (CO) 3 I 3 ] − by cyanide were isolated and structurally characterized. The infrared trend of this series demonstrates the effect of the electronic properties of ligands on the coordinated CO stretching frequencies.
Validation of an Instrument to Measure High School Students' Attitudes Toward Fitness Testing

Purpose The purpose of this investigation was to develop an instrument that has scores that are valid and reliable for measuring students' attitudes toward fitness testing. Method The method involved the following steps: (a) an elicitation study, (b) item development, (c) a pilot study, and (d) a validation study. The pilot study included 427 student-completed instruments from 3 schools. Pilot study data analyses were conducted resulting in a proposed model for the final study. Participants for the final study were 1,199 students (524 boys and 675 girls) from 13 schools. Thirty-six experts in physical education pedagogy were the participants of the content validity study. Results The data fit a model with 4 factors: cognitive, affective-enjoyment, affective-feelings, and affective-teacher. Fit statistics from the confirmatory factor analysis indicated an overall good fit of the data to this model. Goodness of Fit Index (GFI), GFI Adjusted for Degree of Freedom, root mean square error of approximation, Ben...
Characterization of Follistatin-Type Domains and Their Contribution to Myostatin and Activin A Antagonism

Follistatin (FST)-type proteins are important antagonists of some members of the large TGF-β family of cytokines. These include myostatin, an important negative regulator of muscle growth, and the closely related activin A, which is involved in many physiological functions, including maintenance of a normal reproductive axis. FST-type proteins, including FST and FST-like 3 (FSTL3), differentially inhibit various TGF-β family ligands by binding each ligand with two FST-type molecules. In this study, we sought to examine features that are important for ligand antagonism by FST-type proteins. Previous work has shown that a modified construct consisting of the FST N-terminal domain (ND) followed by two repeating follistatin domains (FSD), herein called FST ND-FSD1-FSD1, exhibits strong specificity for myostatin over activin A. Using cell-based assays, we show that FST ND-FSD1-FSD1 is unique in its specificity for myostatin as compared with similar constructs containing domains from FSTL3 and that the ND is critical to its activity. Furthermore, we demonstrate that FSD3 of FST provides affinity to ligand inhibition and confers resistance to perturbations in the ND and FSD2, likely through the interaction of FSD3 of one FST molecule with the ND of the other FST molecule. Additionally, our data suggest that this contact provides cooperativity to ligand antagonism. Cross-linking studies show that this interaction also potentiates formation of 1:2 ligand-FST complexes, whereas lack of FSD3 allows formation of 1:1 complexes. Altogether, these studies support that domain differences generate FST-type molecules that are each uniquely suited ligand antagonists.
Origin and central projections of rat dorsal penile nerve: Possible direct projection to autonomic and somatic neurons by primary afferents of nonmuscle origin

Cell number, size, and somatotopic arrangement within the spinal ganglia of the cells of origin of the rat dorsal penile nerve (DPN), and their spinal cord projections, were studied by loading the proximal stump of the severed DPN with horseradish peroxidase (HRP). The DPN sensory cells were located entirely in the sixth lumbar (L6) dorsal root ganglia (DRG), in which a mean of 468 78 cells per side were observed, measuring 26.7 + 0.8 pm in their longest axis (range 10-65 pm) and distributed apparently randomly within the ganglia. Within the spinal cord, no retrograde label was found, i.e., no motoneurons were labeled, indicating that in the rat the DPN is formed exclusively of sensory nerve fibers. Although labeled fibers entered the cord only through L6, transganglionically transported HRP was evident in all spinal segments examined, i.e., TI3-S2. Labeled fibers projected along the inner edge of the dorsal horn (medial pathway) throughout their extensive craniosacral distribution. However, laminar distribution varied with spinal segment. In the dorsal horn, terminals or preterminal axons were found in the dorsal horn marginal zone (lamina I), the substantia gelatinosa (lamina 111, the nucleus proprius (laminae I11 and IV-the most consistent projection), Clarke's column (lamina VI), and the dorsal gray commissure. In the ventral horn, terminals were found in lamina VII and lamina IX. Label apposed to cell somas and dentrites in lamina VII may represent direct primary afferent projections onto sympathetic autonomic neurons. In lamina IX, labeled terminals delineated the somas and dendrites of cells that appeared to be motoneurons. This is the first description of an apparently monosynaptic contact onto motoneurons by a primary afferent of nonmuscle origin.
Simulated laser fluorosensor signals from subsurface chlorophyll distributions

A semianalytic Monte Carlo model has been used to simulate laser fluorosensor signals returned from subsurface distributions of chlorophyll. This study assumes the only constituent of the ocean medium is the common coastal zone dinoflagellate Prorocentrum minimum. The concentration is represented by Gaussian distributions in which the location of the distribution maximum and the standard deviation are variable. Most of the qualitative features observed in the fluorescence signal for total chlorophyll concentrations up to 1.0 microg/liter can be accounted for with a simple analytic solution assuming a rectangular chlorophyll distribution function.
Designing the design process: exploiting opportunistic thoughts

This study shows that top-down decomposition is problematic in the early stages of design. Instead, an opportunistic decomposition is better suited to handle the ill-structuredness of design problems. Designers are observed interleaving decisions at various levels of abstraction in the solution decomposition. The verbal protocols of three professionals designing a software system of realistic complexity are analyzed to determine the frequency and causes of opportunistic decompositions. The sudden discovery of new requirements and partial solutions triggered by data-driven rules and associations, the immediate development of solutions for newly discovered requirements, and drifting through partial solutions are shown to be important causes of opportunistic design. A top-down decomposition appears to be a special case for well-structured problems when the designer already knows the correct decomposition. Two cognitive models are briefly discussed in relation to opportunistic design. Finally, implications for training, methods, and computational environments to support the early stages of design are outlined.
Random Generation of Combinatorial Structures using Context-Fee Grammars

Abstract The problem of computing a random combinatorial structure such as balanced strings, trees, and flowcharts arises in a variety of applications, including the evaluation of heuristic algorithms which use these structures. The main challenge here is to assure that each instance of the possible structure has the same probability of selection. A brute-force method of first creating a list of all instances of the structure with a given size, say, and then choosing one from the list at random is typically impractical because of the very large number of instances. We provide here a unified approach, using context-free grammars as a backbone for defining the desired combinatorial structure, for efficiently generating a random instance of that structure. The algorithm typically takes a linear or quadractic amount of time in the size of the structure, following some initial computations which is also polynomial in the size of the structure.
Chimpanzees: The Culture-Zone Concept Becomes Untidy

The discovery that chimpanzees in Cameroon use stone tools reinvigorates a long-standing puzzle: what explains the geographical distribution of chimpanzee traditions?
Exact Bayesian estimation of system reliability from component test data

System reliability is often estimated by the use of components' reliability test results when system test data are not available, or are very scarce. A method is proposed for computing the exact posterior probability density function, cumulative distribution function, and credible intervals for system reliability in a Bayesian setting, with the use of components' prior probability distributions and current test results. The method can be applied to series, parallel, and many mixed systems. Although in theory the method involves evaluating infinite series, numerical results show that a small number of terms from the infinite series are sufficient in practice to provide accurate estimates of system reliability. Furthermore, because the coefficients in the series follow some recurrence relations, our results allow us to calculate the reliability distribution of a large system from that of its subsystems. Error bounds associated with the proposed method are also given. Numerical comparisons with other existing approaches show that the proposed method is efficient and accurate.
Loss of low-affinity nerve growth factor receptor during malignant transformation of the human prostate.

Background: The low-affinity nerve growth factor receptor (LNGFR) exhibits an inverse association of epithelial expression with the degree of differentiation of prostate adenocarcinoma tissue. However, the stage at which loss of LNGFR expression is first manifested in the malignant prostate has not been determined. Methods: In order to characterize loss of LNGFR expression in the clinically localized malignant prostate of untreated patients, the pattern of expression of the LNGFR was examined in nonmalignant tissues, consisting of normal and prostatic intraepithelial neoplastic tissues, and in malignant tissues that had been graded by Gleason's scores and categorized into well, moderately, and poorly differentiated adenocarcinomas. In order to determine whether there was an inverse correlation between LNGFR expression and prostate-specific antigen (PSA) secretion, preoperative concentrations of PSA in the serum were also analyzed in relation to the differentiative state of the adenocarcinomas. Results: Premalignant prostate tissues exhibited expression of the LNGFR on all epithelia, whereas in malignant prostate tissues a proportion of epithelia exhibited loss of expression of the LNGFR. An increase in Gleason score of the adenocarcinoma tissue was associated with an increase in the proportion of epithelia that exhibited loss of expression of the LNGFR. Moreover, the proportion of epithelia expressing the LNGFR was inversely correlated with an increase in the concentration of serum PSA. The loss of LNGFR expression was first manifested in epithelia that occurred toward the center of adenocarcinoma tissue. Furthermore, extensive loss of expression of the LNGFR of approximately 63% occurred in well-differentiated adenocarcinomas. Conclusions: These observations demonstrate that loss of LNGFR expression is first observed in well-differentiated malignant epithelia. Hence, loss of the LNGFR may be indicative of the initial stages of malignant transformation of prostate epithelia, as well as all subsequent stages of prostate adenocarcinomas.
Recovery of lotic periphyton communities after disturbance

Periphyton communities represent potentially excellent candidates for assessing the recovery of lotic ecosystems after disturbance. These communities are ubiquitous, relatively easy to sample and measure (in terms of total community biomass), have short generation times, and may influence the recovery rates of higher trophic levels. The first section of this article analyzes how site availability, species availability, and differential species performance influence periphyton successional dynamics. This background information provides a foundation for understanding how periphytic organisms respond after a disturbance. The second section of this article analyzes how periphyton communities respond to four different types of disturbance (flood events, desiccation, organic nutrient enrichment, and toxic metal exposure). Although data are limited, it is concluded that the fast growth rates and short generation times of periphytic organisms, coupled with their flexible life history strategies and good dispersal ability, allow lotic periphyton communities to recover relatively quickly after a disturbance. In addition, disturbance type and severity, local environmental conditions, and site-specific factors also will influence recovery rates.
Determination of α-pinene-derived organic nitrate yields: particle phase partitioning and hydrolysis

Abstract. The hydroxyl radical oxidation of α-pinene under high NO x conditions was studied in a photochemical reaction chamber to investigate organic nitrate (RONO 2 ) production and partitioning between the gas and particle phases. We report an organic nitrate yield of 26 ± 7% from the oxidation of this monoterpene in the presence of nitric oxide (NO). However, the organic nitrate yield was found to be highly dependent on both chamber relative humidity (RH) and seed aerosol acidity, likely as a result of particle phase hydrolysis. The particle phase loss of organic nitrates perturbs the gas-particle equilibrium within the system, leading to decreased RONO 2 yields in both the gas and particle phases at elevated RH and an apparent non-equilibrium partitioning mechanism. This resulted in smaller apparent partition coefficients of the total organic nitrate species under high chamber RH. The hydrolysis of particle phase organic nitrates at low chamber relative humidity in this study implies that aerosol partitioning of organic nitrates may be an important sink for atmospheric NO x and may have a significant impact on regional air quality.
Static and Fatigue Behavior of Epoxy/Fiberglass Composites Hybridized with Alumina Nanoparticles

Advanced composites are hybridized by the integration of alumina nanoparticles into the matrix and onto the fabric surface. Alumina was pre-dispersed by sonication. Pre-processing of alumina was ca...
Supply chain models for an assembly system with preprocessing of raw materials

In this paper, we investigate the material procurement and delivery policy in a production system where raw materials enter into the assembly line from two different flow channels. The system encompasses batch production process in which the finished product demand is approximately constant for an infinite planning horizon. Two distinct types of raw materials are passed through the assembly line before to convert them into the finished product. Of the two types of raw materials, one type requires preprocessing inside the facility before the assembly operation and other group is fed straightway in the assembly line. The conversion factors are assigned to raw materials to quantify the raw material batch size required. To analyze such a system, we formulate a nonlinear cost function to aggregate all the costs of the inventories, ordering, shipping and deliveries. An algorithm using the branch and bound concept is provided to find the best integer values of the optimal solutions. The result shows that the optimal procurement and delivery policy minimizes the expected total cost of the model. Using a test problem, the inventory requirements at each stage of production and their corresponding costs are calculated. From the analysis, it is shown that the rate and direction change of total cost is turned to positive when delivery rates per batch reaches close to the optimal value and the minimum cost is achieved at the optimal delivery rate. Also, it is shown that total incremental cost is monotonically increasing, if the finished product batch size is increased, and if, inventory cost rates are increased. We examine a set of numerical examples that reveal the insights into the procurement-delivery policy and the performance of such an assembly type inventory model.
Increased incidence of anti-β-amyloid autoantibodies secreted by Epstein-Barr virus transformed B cell lines from patients with Alzheimer's disease

During the past several years, evidence has been accumulated to support the thesis that immunological factors may play some role in Alzheimer's disease (AD). We have characterized the reactive antigens detected by certain monoclonal antibodies secreted by Epstein-Barr virus (EBV)-transformed B cell lines from the peripheral blood of AD patients and controls. Autoantibodies against beta-amyloid protein beta-amyloid protein (beta-A) in amyloid plaques and blood vessels and in enzyme-linked immunosorbent assays (ELISA) have been reported in four cell lines derived from an AD patient. In this study, over 3300 EBV-transformed B cell lines from thirteen individuals were tested in ELISAs for antibodies against beta-A peptides. Significantly more autoantibodies against beta-A (1-40) were found in the AD group, 2.26 +/- 0.62% (39/1794 cell lines) than in the control group, 0.28 +/- 0.36% (5/1552 cell lines) with P < 0.005. These new antibodies did not react with plaques or amyloid deposits in blood vessels. In contrast to the four plaque-reactive autoantibodies which reacted better with beta-A (1-40) than with beta-A (1-28), 70% of these anti-beta-A (1-40) antibodies reacted as well or better with beta-A (1-28). Many of them were also reactive with beta-A (1-16). Tested against a panel of cytoskeletal proteins and Hela cells, many of these anti-beta-A (1-40) antibodies appear to be polyreactive. The higher incidence of anti-beta-A antibody secreting B cells in AD patients provides further evidence that autoimmunity may play a role in AD.
Wikipedia and the emergence of dialogic expertise

Wikipedia's popularity as an online encyclopedia calls attention to fundamental assumptions about the management and dissemination of information. Drawing on a Bakhtinian framework, this article posits a model of dialogic expertise. Specifically, it argues that, by facilitating an ongoing chain of interdependent and multivocal “utterances,” Wikipedia challenges traditional “monologic” expertise. Nonetheless, the site's purportedly democratic defiance of knowledge elites (of encyclopedic publishing, academe, etc.) is compromised by the establishment of a “technocratic” hierarchy. Implications extend to the scholarly debate surrounding dialogue and rhetoric and to our understanding of Wikipedia's success in the context of a cultural anxiety—Americans are at once dependent on an extensive system of experts and uneasy about the deferential distribution of power within that system.
Molecular beam epitaxial growth of GaInSbBi for infrared detector applications

Abstract The growth of a new quaternary semiconductor alloy GaInSbBi suitable for 8–12 μm infrared detector applications by molecular beam epitaxy is reported for the first time. By the introduction of Ga into the InSbBi alloy, the following have been achieved: (1) enhancement of Bi incorporation, (2) improved lattice-matching to InSb, and (3) suppression of multiple-phase growth and improved surface morphology. The dependence of Bi content and surface morphology on growth temperature and substrate orientation has been investigated. Significant improvement in surface morphology is achieved for films grown on large angle off-axis substrates including (311)A and (511)A. Infrared absorption measurements performed at 77 K indicate that a cutoff wavelength as long as 10.7 μm was achieved. The principles demonstrated in this work are quite general and can be applied to other quaternary material systems containing N, P, As, and Sb such as GaInTlSb and GaInAsN to cover a wide range of band gaps.
Access Disparity Mitigation in Multi-hop Wireless Networks

In Multi-hop Wireless Networks (MWNs), the end-to-end performance degrades exponentially with hop counts and the degree of traffic aggregation at each hop. Fair allocation of bandwidth among nodes is one of the challenging problems in MWNs. The IEEE 802.11 distributed coordination function standard stipulates long-term equalization of throughput among stations by giving the same number of transmission opportunities regardless of their individual bit rates. In this paper, we propose a bandwidth allocation scheme for MWNs that uses the underlying hop contention graph, along with hop counts and traffic aggregates in order to achieve a long-term equalization of the end-to-end throughput. The proposed scheme first determines direct and indirect (hidden) contentions among nodes, it then finds the end-to-end upstream and downstream access probabilities, and finally allocates access opportunities accordingly. The scheme significantly improves fairness among nodes. The performance, in terms of throughput, delay, and fairness, has been studied under various traffic sources, traffic loads, and different network topologies.
Statistical analysis of optical turbulence intensity over a 2.33 km propagation path.

Refractive index and microclimate fluctuations can significantly affect free-space laser communications. To better understand these physics relationships, optical scintillometer data were collected over a near-horizontal propagation path along with in-situ rooftop measurements of temperature variance. Regression analysis of time-averaged data revealed that fairly high correlation values (i.e., R ≥ 0.80) occurred in 8 of 21 cases studied. Analysis suggests that point sensors can provide valuable information on optical turbulence for extended paths. Additional research is recommended to further explore point measurements and their relation to integrated values of optical turbulence over inhomogeneous paths.
Relationships between in Vitro Genetic Toxicity and Carcinogenidty Studies in Animals

In vitro genetic toxicity assays currently in use cannot be used to unambiguously define all potential carcinogens. The relationship between the various in vitro endpoints (mutation, cytogenetic effects, transformation) and the patterns of tumorigenicity is quite complex. Additional data, particularly for noncarcinogens, are needed to better understand the inconsistencies and to define the limits of predictability. For example, we must empirically define the concordance and discordance between in vivo and in vitro systems related to chemical classes or structures. At this time, since there are no nontrivial generalizations and no general predictivity is possible, we must use judgment in applying short-term test results. There is a clear need to identify as soon as possible the minimum number of in vitro systems that can be used, nonredundantly, to discriminate between carcinogens and noncarcinogens. However, we must continue to address the sources of discordance in order to understand the ways in which short-term test results can and cannot be used. Many trans-sex/trans-species carcinogens show the capacity to induce multiple endpoints of genetic toxicity and this class of rodent carcinogens may have the greatest implications for potential human health effects. A much more selective use of short-term test results to identify potential carcinogens such as these will achieve many of the goals for which these tests were developed.
Ductile crack growth-I. A numerical study using computational cells with microstructurally-based length scales

Many metals which fail by a void growth mechanism display a macroscopically planar fracture process zone of one or two void spacings in thickness characterized by intense plastic flow in the ligaments between the voids; outside this region, the voids exhibit little or no growth. To model this process a material layer containing a pre-existing population of similar sized voids is assumed. The thickness of the layer, D, can be identified with the mean spacing between the voids. This layer is represented by an aggregate of computational cells of linear dimension D. Each cell contains a single void of some initial volume. The Gurson constitutive relation for dilatant plasticity describes the hole growth in a cell resulting in material softening and, ultimately, loss of stress carrying capacity. The collection of cells softened by hole growth constitutes the fracture process zone of length l1. Two fracture mechanism regimes can be identified corresponding to l1 ≈ D and l1 ⪢ D. The connection between these mechanisms and fracture resistance is discussed. Finite element calculations have been carried out to determine crack growth resistance curves for plane strain, mode I crack growth under small scale yielding. A row of voided cells is placed on the symmetry plane ahead of the initial crack. These cell elements are embedded within a conventional elastic-plastic continuum. Under increasing load, the voids in the cells grow and coalesce to form a new crack surface thereby advancing the crack. Resistance curves are calculated for crack growth exceeding many multiples of D. The parameters affecting fracture resistance are discussed emphasizing the roles of microstructural parameters and continuum properties of the material. The effect of crack tip constraint on fracture resistance is examined under small scale yielding by way of the T-stress. As a final application, resistance curves for a deep and a shallow crack bend bar are computed. These are compared with experimental data.
Stable isotope chronology and climate signal calibration in neotropical montane cloud forest trees

without annual growth rings. High-resolution d 18 O measurements are used to identify regular cycles in wood of up to 9%, which are associated with seasonal changes in precipitation and moisture sources. The calculated annual growth rates derived from the isotope time series match those observed from long-term basal growth measurements. Interannual variability in the oxygen isotope ratio of lower forest trees is primarily related to interannual changes in wet season precipitation. Forward modeling independently supports our detection of both annual chronology and a climate signal. The confirmation of annual chronology and sensitivity to interannual climate anomalies suggests that tropical cloud forest dendroclimatology can be used to investigate local and regional hydroclimatic variability and change.
Developing Enhanced Blood-Brain Barrier Permeability Models: Integrating External Bio-Assay Data in QSAR Modeling.

Purpose Experimental Blood–Brain Barrier (BBB) permeability models for drug molecules are expensive and time-consuming. As alternative methods, several traditional Quantitative Structure-Activity Relationship (QSAR) models have been developed previously. In this study, we aimed to improve the predictivity of traditional QSAR BBB permeability models by employing relevant public bio-assay data in the modeling process.
Contingency factors in negative practice of smoking.

Summary.-100 cigarette smokers were randomly assigned to 1 of 5 treatment groups balancing the level of smokers within groups. To uncover the importance of chaining in overresponding or satiation treatments of cigarette smoking, 2 of these groups were required to double or triple their baserate in 2 or 3 cigarene chains while a third group simply doubled their daily consumption. For comparison, a fourth group received covert sensitization treatment of their smoking while a fifth group acted as an anention-monitoring control. Following 1 wk. of cigarette-by-cigarette baserate each group received 1 wk. of treatment and 3 wk. of follow-up meetings. Contacts with all subjects were also made 3 and 6 mo. after treatment. All groups significantly decreased smoking following treatment, but the 3-mo. follow-up showed no significant difference from baserate. Group differences were not statistically significant, although the attention-monicoring group was least effective at all posttreatment measurement points. Although subject reports indicate chaining increased the aversiveness of the negative practice regime, it showed no effect on treatment efficiency.
Perceived Discrimination Among Three Groups of Refugees Resettled in the USA: Associations With Language, Time in the USA, and Continent of Origin

The objectives of this study were to assess the prevalence and predictors of discrimination among a community-based sample of refugees resettled in the USA. We sought to test whether language, gender, time in the USA and country of origin were associated with the experience of discrimination among individuals resettled in the USA as part of the refugee resettlement program. Perceived discrimination was assessed among individuals from East Africa (n = 92), West Africa (n = 74), and from Eastern Europe (n = 112) using a multi-item measure of discrimination. Bivariate associations revealed statistically significant associations between experiences of discrimination and time in the USA, language ability, and sending country. A logistic regression model revealed that refugees from African sending countries were more likely than Eastern European individuals to experience discrimination, even after controlling for potentially confounding factors. We interpret this finding as evidence of racism and discuss the implications for population health and resettlement practice.
ADIABATIC INVARIANTS OF PERIODIC CLASSICAL SYSTEMS

Recently there has been renewed interest in adiabatic invariants of simply-periodic classical systems subject to perturbation by slow variation of parameters. In several interesting cases it has been shown that if the system varies slowly from one steady state to a different steady state, the appropriate adiabatic invariant is constant to an arbitrarily high order in a slowness parameter.It is shown here how these and similar results may be derived by systematic use of a technique of perturbation theory of classical Hamiltonian systems. The method is essentially iteration of the transformation to action and angle variables.
Oxytocin in plasma of pregnant, lactating and cycling ewes during vaginal stimulation.

A method for extracting and concentrating oxytocin from blood, combined with a sensitive bioassay for oxytocin performed on the isolated rat mammary strip, was utilized to determine the effect of vaginal distention on the level of oxytocin in the plasma of lactating, pregnant and normally cycling ewes. Before distention, plasma of lactating and cycling ewes contained about 6 μU oxytocin/ml plasma. The plasma oxytocin concentration increased by 133 ± 29 % (mean ±SE) and 123 ±16%, respectively, in those 2 groups of animals during the first minute of stimulation. In pregnant animals, by contrast, the plasma oxytocin titer decreased 48 ± 5 % from a control level of 11 ±2 μU/ml plasma. The conclusion that some factor peculiar to pregnancy interferes with the reflex release of oxytocin in response to vaginal stimulation is discussed. (Endocrinology 83: 272, 1968)
Secondary intracranial neoplasia in the dog: 177 cases (1986-2003).

Background: This study investigates the frequency, location, and clinical findings associated with 177 secondary brain tumors in dogs. Hypothesis: Secondary intracranial neoplasia is more common than primary intracranial neoplasia in dogs during the time period studied, and hemangiosarcoma (HSA) is the most common secondary intracranial tumor. Animals: One hundred and seventy-seven client-owned dogs presented to the Matthew J. Ryan Veterinary Hospital between 1986 and 2003. Methods: Medical records were searched for a diagnosis of intracranial neoplasia in dogs who underwent complete postmortem examination. Of these dogs, those with a diagnosis of primary intracranial neoplasia were excluded. Results: Of the 177 secondary brain tumors, 51 (29%) were HSAs, 44 (25%) were pituitary tumors, 21 (12%) were lymphosarcomas, and 21 (12%) were metastatic carcinomas. The average age at diagnosis was 9.6 ± 3.0 years. Most tumors were located in the cerebrum, and a mentation change was the most common presenting clinical sign. On postmortem examination, the same tumor that was in the brain was also present in the lung in 84 cases (47%), in the kidney in 62 cases (35%), and in the heart in 55 cases (31%). Conclusions and Clinical Importance: Secondary intracranial neoplasia in dogs was more common than primary intracranial neoplasia during the time period studied. Many of these dogs had related disease in other body systems that was apparent on diagnostic tests such as thoracic radiography.
On the design of reactionless 3-DOF planar parallel mechanisms

A reactionless machine will not apply reaction forces and moments on the mounting base during motion. This article presents the theory for design of a reactionless planar parallel mechanism. The salient features of this design are: (i) it uses auxiliary parallelograms to locate the center of mass of each leg at the base, (ii) choice of geometric and inertial parameters to satisfy the reactionless conditions and/or selection of trajectory to achieve a reactionless design. We illustrate the reactionless feature of such a mechanism through computer simulations.
A planarized, capacitor-loaded loop structure for wireless power transfer

Simulation, optimization, and implementation of a capacitor-loaded wireless power transfer structure at 6.78 MHz are presented. It is found that the optimal configuration for this structure is coplanar and that by replacing thick wire with copper strip, a planarized structure can be obtained. It is also shown by simulation that the capacitor-loaded structure is not strongly affected by nearby dielectric materials.
An offset finite element model and its applications in predicting sheet metal assembly variation

Dimensional variation in sheet metal assembly affects product fit and functionality. To predict the variation of assembled products, variation simulation analysis has been gradually adopted in the early design stage. However, variation simulation based on rigid body assumptions usually results in over estimation of the assembly variation. In this paper, we propose an offset beam element model for predicting the assembly variation of deformable sheet metal parts joined by resistance spot welding. The purpose of using the offset beam element is to include the shear effect provided by resistance spot weld nuggets that cannot be captured by the conventional beam element. The offset element is then applied to predict sheet metal assembly variation for one-dimensional (1D) models extracted from industrial practice. The first example evaluates the effects of sheet metal thicknesses on assembly variation. The second example shows how the assembly sequence affects assembly variation. These models provide interesting insights into the mechanisms of variation stackup and will lead to the understanding of more complex sheet metal assemblies.
The clock is ticking: The role of uncertainty, regulatory focus, and level of risk on supply chain disruption decision making behavior

Abstract Supply chain employees must make decisions on when and how to react to potential and realized supply chain disruptions. Drawing on regulatory focus theory, we examine how an individual’s regulatory focus, level of risk, as well as the uncertainty of the supply chain disruption affect willingness to pursue a new disruption mitigation strategy. Employing a vignette-based field experiment, we present and discuss findings related to supply chain risk decision making. These findings have implications for future behavioral supply chain risk research.
MSB estimation of bound fraction: bias from binding energy uncertainty

Magnetic spectroscopy of nanoparticle Brownian motion, MSB, uses the magnetization produced by magnetic nanoparticles in a sinusoidal magnetic field, which can be observed remotely at low enough concentrations to enable it to be used for "molecular imaging". The MSB signal is sensitive to chemical binding, temperature and viscosity. If the MSB signals from nanoparticles in multiple bound states are known, a mixture model can be used to find the concentration of nanoparticles in each bound state. The accuracy has been shown to be high for two and three bound states. However, if the bound states are not accurately known, as is often the case in vivo, the model is perturbed significantly. Using simulations of two bound states based on the effective field approximation to the Fokker-Planck equations, we show that the error in the bound fraction is roughly proportional to the error in the bound state relaxation time. The errors in bound fraction were roughly proportional to the error in the relaxation time for the bound state used in the mixture model. The largest errors occurred for short relaxation time bound states. But for all bound state relaxation times, 10% errors in the relaxation time of the bound state resulted in errors in the bound fraction of less than 10%.
Breakwell memorial lecture: Review of Astrodynamics, 1958 – 2001 - a personal perspective

Abstract A review of Astrodynamics during the 43 year career of the author is presented. The following projects/programs are reviewed: (1) launch vehicles-as launchers of small satellites and also the use of advanced robust reduced order techniques for autopilot control of contemporary flexible, expendable systems; (2) the use of the Clohessy-Wiltshire equations for the Gemini mission rendezvous, and recently in constellation formation flying station keeping; (3) lessons learned from the design of attitude control system for gravity-gradient and dual-spin spacecraft; (4) design of attitude control systems for large, flexible space platforms and antenna systems; (5) participation in the original Tethered-Shuttle-Subsatllite system and other proposed orbiting tethered systems; and (6) integrated structural/control optimization of large (articulated) structures in low Earth orbit. This review will emphasize lessons learned as well as advances in astrodynamics techniques/concepts.
Scrapbooking as an Intervention for Grief Recovery With Children

ABSTRACT This article describes scrapbooking in the context of bereavement counseling. For the purposes of this article, scrapbooking combines many different types of art-related therapy interventions into one concrete format to utilize in counseling with children who are working to overcome grief or trauma related to the loss of a parent. A case illustration is provided, along with a sample scrapbook page, timeline, and the materials needed.
The methylation of tRNA in KB cells after treatment with actinomycin D

Abstract Extensive shifts in the distribution of labeled methylated constituents of tRNA were observed in KB cells treated with actinomycin D for 30 min prior to a 90-min pulse with 3H-CH3-methionine. Although this treatment completely blocked the synthesis of tRNA, methylation continued to the extent of 12–15% of controls (pulsed without antibiotic). Under this condition the relative proportion of radioactivity incorporated into 3-methylcytosine, N2-methylguanine and 2′-O-methylribose was markedly increased (170–235% of control values), it was moderately reduced in 1-methyladenine, 5-methyl-cytosine and 5-methyluracil (35–70% of controls) and markedly reduced in 1-, 7- and N2N2-methylguanines (15–30% of controls). These data suggest that specific types of methylations occur at particular times during the processing of pre-tRNAs.
Does limited access at school result in compensation at home? The effect of soft drink bans in schools on purchase patterns outside of schools

This paper investigates the effects of soft drink bans in schools on purchases outside of schools. Using unique household-level data, we exploit the implementation of a state-mandated ban on soft drinks in Connecticut (USA) in a triple difference approach. We compare soft drink purchases of households with school-age children before and after implementation with purchases of households without school-age children in Connecticut, as well as households with and without school-age children in other states. Our analysis does not support the notion that school-age children compensate for the limited availability at school with increased consumption at home.
Significance of isolated bradycardia detected by home monitoring.

Abstract Objective: To determine the cause of isolated bradycardia during home cardiorespiratory monitoring. Setting: A tertiary care hospital. Study design: A retrospective review of the charts of 8 patients with severe isolated bradycardia on their home monitoring reports. All subjects underwent polysomnography including a pH probe. Results: Monitor reports showed a characteristic pattern of long (30 to 60 seconds) periods of bradycardia, sometimes with asystole, associated with irregular respiratory efforts. All patients had severe gastroesophageal reflux, with a pH