cssi/SciSciGPT-SciSciNet huggingface dataset:
Structure of 22,12-Polyurethane in Chain-Folded Lamellar Crystals

Aliphatic 22,12-polyurethane has been crystallized directly from the melt and isothermally at 105 °C from N,N-dimethylformamide to give chain-folded lamellae of thickness ≈ 14 nm. The crystals have been investigated using X-ray diffraction, electron microscopy (imaging and diffraction), and computer modeling. The diffraction data was used to establish that the chains crystallize in a single-chain, triclinic unit cell, and the structure bears a strong resemblance to chain-folded lamellar crystals of even−even nylons. The results show that, even for a molecule with relatively long alkane segments, the hydrogen bonds exercise a controlling influence on the crystallization process and crystalline structure. Two models were investigated: one based on an analogy with nylon 6 6 and the other derived using molecular dynamics; they both turned out to be closely related. The model generated using molecular dynamics predicted localized rotations at the termini of the ester−amide coupled units. The resolution of the...
Design, and initial experiment results of a novel LH launcher on Alcator C-Mod

The design, construction and initial results of a new lower hybrid current drive (LHCD) launcher on Alcator C-Mod (Hutchinson et al 1994 Phys. Plasmas 1 1511) are presented. The new LHCD launcher (LH2) is based on a novel splitter concept which evenly distributes the microwave power in four ways in the poloidal direction. This design allows for simplification of the feeding structure while keeping the flexibility to vary the peak launched toroidal index of refraction, Ntoroidal, from ?3.8 to 3.8. An integrated model predicts good plasma coupling over a wide range of edge densities, while poloidal variations of the edge density are found to affect the evenness of power splitting in the poloidal direction. The measured transmission loss is about 30% lower than the previous launcher, and a clean Ntoroidal spectrum has been confirmed. Power handling capability exceeding an empirical weak conditioning limit and reliable operation up to 1.1?MW net LHCD power have been achieved. A survey of antenna?plasma coupling shows the existence of a millimetric vacuum gap in front of the launcher. Fully non-inductive, reversed shear plasma operation has been demonstrated and sustained for multiple current diffusion times. The current drive efficiency, ?LH ? neR0Ip/PLH, of these plasmas is (0.2?0.25) ? 1020?m?2A?W?1, which is in agreement with the expected efficiency on the International Thermonuclear Experimental Reactor (ITER).
In vitro evaluation of corpus luteum function of cycling and pregnant rhesus monkeys: progesterone production by dispersed luteal cells

Corpus luteum function in the cycling and the pregnant rhesus monkey (Macaca mulatta) was evaluated through short term in vitro studies of progesterone production by suspensions of collagenase-dispersed luteal cells in the presence and absence of exogenous gonadotropin (human chorionic gonadotropin, HCG). Cells from mid-luteal phase of the menstrual cycle secreted progesterone, as measured by accumulation of this hormone in the incubation medium, and responded to the addition of 100 ng HCG/ml with a marked increase in progesterone secretion significantly above basal level (63.7 +/- 13.1 versus 24.7 +/- 5.5 ng progesterone/ml/5 x 10(4) cells/3 hr, X +/- S.E., n =6 ; p less than 0.05). However, luteal cells from early pregnancy (23-26 days after fertilization) secreted siginificantly less progesterone than cells of the non-fertile menstrual cycle (3.6 +/- 2.4 versus 24.7 +/- 5.5 ng/ml/5 x 10(4) cells/3 hr, n =3 ; p less than 0.05) and did not respond to HCG with enhanced secretion. By mid-pregnancy (108-118 days gestation ) luteal cells exhibited partially renewed function, and near the time of parturition (163-166 days gestation) basal and HCG-stimulated progesterone secretion (30.2 +/- 5.6 and 63.0 +/- 13.0 ng/ml/5 x 10(4) cells/3 hr, respectively; n = 3) was equivalent to that of cells from the luteal phase of the non-fertile menstrual cycle. The data suggest that following a period around the fourth week of gestation, when steroidogenic activity is markedly diminished, the corpus luteum of pregnancy progressively reacquires its functional capacity and at term exhibits gonadotropin-sensitive steroidogenesis similar to that the corpus luteum of the menstrual cycle.
Role of Closed Magnetic Fields in Solar Wind Flow

In this paper we demonstrate how closed magnetic fields appear to be playing a significant role in solar wind flow. Confinement or trapping of plasma is the physical process, while confinement duration, as characterized by the first ionization potential (FIP) bias, is the attribute that divides the fast- and slow-wind regions. The trapped plasma is released along ubiquitous and predominantly radial open field lines, presumably by continual reconnection at the base of the corona, with evidence for this process coming from the appearance of the imprint of polar coronal holes, quiet Sun, and active regions in the outer corona and interplanetary space. When trapping is not long enough to enrich the elemental abundance (FIP bias near 1), the coronal radial density gradient is steep, coronal temperature is low, and a fast wind flows in the overlying corona. However, the presence of closed fields still influences the flow of the fast wind, as revealed by the fact that flow speed is anticorrelated with, or characterized by, the density at the base of the corona. When trapping is long enough to enrich the abundance (FIP bias > 1), a slow wind flows, and FIP bias characterizes its properties. Enhanced FIP bias gives rise to a decreased coronal radial density gradient, as manifested by the extension of coronal streamers in white-light coronal images, increased coronal temperature, and decreased solar wind speed in the overlying corona.
A quantitative paleoecological approach to high-resolution cyclic and event stratigraphy: the Upper Ordovician Miamitown Shale in the Type Cincinnatian

Stratigraphic cycles form an underlying high-resolution chronostratigraphic structure for much of the sedimentary record. However, before their chronostratigraphic utility can be realized they must be reliably correlated. A new integrated cyclic, quantitative lithologic and faunal method of correlating meter-scale cycles has been developed for a 12 m interval of the Miami-town Shale in the Upper Ordovician of the Cincinnati, Ohio area. First, using lithologic criteria alone, six flooding-surface-bound (shale-on-limestone) shoaling-upward (shale-to-limestone) cycles were delineated and correlated between seven outcrop sections within a 30 km radius; many correlations were ambiguous. Unusual fossil occurrences constrain correlations of cycles 3 and 4, and the limited presence of a dalmanellid, Heterorthina fairmountensis, shows that the flooding surface above cycle 3 lies 10 cm below the lithologic limestone-shale contact. Cluster analysis of faunal abundance data constrained correlations between all cycles and showed a major transition at the top of cycle 2, again below the lithologic limestone-shale contact. Finally, faunal depth gradient fluctuations interpreted from ordination of faunal abundance data confirmed and clarified the nature of cycle correlations; the major transition at the top of cycle 2 is a transgressive surface, and the middle part of cycle 3 includes the interval of maximum water depth. These features delineate a larger, 10-m-scale, cyclicity. The smaller, meter-scale cycles, interpreted as averaging 40–100 ka in duration, demonstrate the potential of a ten-to twenty-fold increase in the resolution of the type Cincinnatian stratigraphic record.Ecostratigraphy, faunal cyclicity, cyclic stratigraphy, event stratigraphy epiboles, benthic paleoecology, Upper Ordovician, Maysvillian, Caradocian, Ashgillian, Cincinnati.
Optical Efficiency Factors for Concentric Spheres

Extinction, scattering, and absorption efficiency factors for a concentric sphere of a nonlight absorbing nucleus (m = 1.5) and an absorbing shell (m = 1.95 − 0.66i) were calculated based on the theory of Aden and Kerker. For small size parameters (ν < 1), the magnitude of the extinction efficiency factor is markedly affected by the shell thickness. An approximating equation, based on the Rayleigh light scattering equation, is presented which relates the increase of the extinction efficiency factor of an absorbing sphere over the extinction efficiency factor of a nonabsorbing sphere to the pertinent variables (refractive index and size parameter).
Properties of One-Dimensional Correlated Gaussian Wave Functions

The properties of a certain class of unsymmetrized one-dimensional correlated Gaussian wave functions---those which are ground-state eigenfunctions of some coupled harmonic-oscillator Hamiltonian---are investigated in detail. It is shown that a properly symmetrized wave function constructed from these may be used to calculate the expectation value ${E}_{0}$ of the Hamiltonian appropriate to a system of interacting one-dimensional atoms and that this energy is, to a high degree of accuracy, equal to the value obtained when the unsymmetrized wave function is used. A method is given by which correction terms to ${E}_{0}$ may be obtained. In addition, it is found that even though the number of particles be very large, the necessary multivariable integrals may be performed quite simply.
The Effect of Hypertrophic Cardiomyopathy (HCM) Mutations of Tropomyosin on Force Generation and Cross-Bridge Kinetics in Thin-Filament Reconstituted Bovine Cardiac Muscle Fibers

Two DCM mutations (E40K and E54K) of Tropomyosin (Tm) were examined using the thin-filament extraction and reconstitution technique. Effects of Ca2+, ATP, phosphate and ADP concentrations on force and its transients were studied at 25°C and compared to WT. Both E40K and E54K showed significantly lower high-Ca (pCa 4.66) tension (THC, 1.21±0.06 and 1.24±0.07, respectively), low-Ca (pCa 7.0) tension (TLC, 0.07±0.02 and 0.06±0.02 at pCa 7.0), and Ca2+ activatable tension (Tact=THC-TLC, 1.15±0.08 and 1.18±0.06) compared to WT (THC=1.53±0.07, TLC=0.12±0.01, Tact=1.40±0.07) (±sem, N=8-21 for all studies). All tensions were normalized to Ta, the tension of actin-filament reconstituted myocardium at the standard activating condition. pCa50 (Ca2+ sensitivity) of E40K (5.23±0.02) and E54K (5.24±0.03) was similar to WT (5.26±0.03). The cooperativity increased in both mutants (E40K 3.24±0.29, E54K 3.73±0.25) compared to WT (2.80±0.17). Four equilibrium constants were deduced using sinusoidal analysis. E40K and E54K showed significantly increased K1 (ATP association constant, 2.51±0.40 mM−1 and 1.28±0.26 mM−1, respectively) than WT (0.36±0.06 mM−1). E40K showed significantly higher K2 (cross-bridge detachment step: 1.49±0.17) than E54K (0.80±0.10) and WT (0.82±0.07). E40K also showed significantly lower K4 (force generation step: 0.78±0.12) and K5 (Pi association constant: 0.18±0.03) than E54K (1.52±0.21 and 0.28±0.04, respectively) and WT (2.35±0.43 and 0.39±0.07). The cross-bridge distribution of the three Tms was calculated from the equilibrium constants. E40K showed ∼20% less force generating cross-bridges than WT, but E54K remained similar to WT. These results indicate that, under pCa4.66, force/cross-bridge is ∼20% less in E54K than WT, but remains similar in E40K. We conclude that the decreased force generating ability of these two mutants may be the underlying cause of the pathogenesis of DCM.
Continuous-Time Bilinear System Identification

The objective of this paper is to describe a new method for identification of a continuous-time multi-input and multi-output bilinear system. The approach is to make judicious use of the linear-model properties of the bilinear system when subjected to a constant input. Two steps are required in the identification process. The first step is to use a set of pulse responses resulting from a constant input of one sample period to identify the state matrix, the output matrix, and the direct transmission matrix. The second step is to use another set of pulse responses with the same constant input over multiple sample periods to identify the input matrix and the coefficient matrices associated with the coupling terms between the state and the inputs. Numerical examples are given to illustrate the concept and the computational algorithm for the identification method.
A Highly Accurate Method of Localizing Regions of Neuronal Activation in the Human Brain with Positron Emission Tomography

Functional mapping of the human brain with positron emission tomography (PET) can best be performed by obtaining multiple short measurements of cerebral blood flow in a single sitting. In this manner regional changes in blood flow accompanying the increased neuronal activity from a movement, sensation, or even cognition task, have been identified. However, localizing a functional region with PET has been severely limited by the poor resolving properties of PET devices. Using a new method of data analysis we recently reported the mapping of visual field stimuli on human visual cortex with surprisingly high reliability as measured by the low standard deviation in positions across different subjects (as low as 1 mm). In this work the analysis technique enabling such high-resolution functional brain mapping is fully described. Additionally, simulations are presented to illustrate its advantages and limitations.
Trends in Same‐gender Sexual Partnering, 1988–1998

Nationally representative data from the General Social Surveys indicate that from 1988 to 1998 there was an increasing likelihood that American men and women had had a same‐gender sexual partner during the previous year. Increases in same‐gender sexual partnering and decreases in exclusively opposite‐gender sexual partnering during the previous 5 years were also evident among women over the 1988–1998 period. Same‐gender sexual partnering was found to be associated with age, birth cohort, race, size of hometown at age 16, and mothers’ education. The increase in same‐gender sexual partnering over the 1988–1998 period persisted after controlling for these factors. Several possible explanations for the trend are discussed.
Diced Cartilage Grafts Wrapped in AlloDerm for Dorsal Nasal Augmentation

Dorsal nasal augmentation is commonly performed for various aesthetic deficiencies and/or reconstructive defects such as the saddle nose deformity. However, the optimal technique for volume augmentation has yet to be identified. The senior author (F.P.) has since developed a new modified technique using wrapped diced cartilage within an AlloDerm. This novel construct provides the plastic surgeon a smooth, convenient, pliable option with similar operative times as compared with other popular techniques. In summary, this technique has been proven to be successful in achieving attractive, safe, and acceptable outcomes in nasal dorsal configuration and overall patient satisfaction.
Absenteeism from work: the experience of employed breast and prostate cancer patients in the months following diagnosis.

Background: A better understanding of how cancer treatments affect patient's employment may help patients and physicians make more informed choices between treatment alternatives. This study examined the number of days employed patients undergoing treatment for either breast or prostate cancer were absent from their jobs. Method: Using the Detroit Surveillance, Epidemiology, End-Results registry, all potentially eligible women diagnosed with breast cancer and men diagnosed with prostate cancer were selected. Subjects who were employed full-time were included in this analysis. Results: Women treated for breast cancer missed an average of 44.5 days from work; the median days missed was 22. The median days missed by women treated with surgery and chemotherapy was 40. Men diagnosed with prostate cancer missed an average of 27 days (median days=20) from work. The median days missed for men treated surgically without hormone or radiation therapy was 25. In multivariable analyses, taking a leave of absence and greater elapsed time from diagnosis to interview were associated with the greatest number of days absent from work for all patients. Men treated with hormone and/or radiation therapy or who were not treated missed fewer days from work relative to men undergoing surgery. Conclusion: Research and interventions are needed to minimize work loss for cancer patients. Vocational rehabilitation programs may minimize the impact of treatment on work. Information on how treatments may infringe the ability for patients to earn a living may influence treatment decisions. Copyright © 2005 John Wiley & Sons, Ltd.
Heterogeneous mantle domains: signatures, genesis and mixing chronologies

Abstract A Sr Nd Pb isotope data base is available now which includes over 300 samples from some 43 oceanic islands or island groups. This data base supports the identification by Zindler and Hart [20] of four principal end-member isotopic components in oceanic basalts: depleted MORB mantle (DMM), high U/Pb mantle (HIMU) and two enriched mantle components (EMI, EMII). Linear mixing arrays (in five isotopic dimensions) between EMI and HIMU and between DMM and HIMU are documented and argue for similar proportions of Sr Nd Pb in these three components. EMI is argued to be a slightly modified bulk-earth component; HIMU is a component with a greatly enhanced U/Rb ratio, probably generated by intra-mantle metasomatism. It is unlikely that either EMI or HIMU are recycled oceanic crust or sediment. EMII is easily reconciled with a recycled (subducted) sediment protolith; this leads to strong Pb enrichment and consequently to markedly curved mixing arrays between EMII and the other components. The DUPAL anomaly is demonstrated to be unequivocally real, and is marked by basalts with enhanced contents of EMI, EMII, or HIMU; polar regions are marked by only weak or absent signatures from these components. Not all basalts from the DUPAL belt show a strong DUPAL signature, but 95% of all basalts showing a strong DUPAL signature lie between 0° and 50° south latitude. The mesosphere boundary layer model of Allegre and Turcotte [21] is shown to be consistent with available data, provided a somewhat ad-hoc plea is made for preferential recycling of sediments and delaminated continental lithosphere within the DUPAL latitudes. An alternative model is proposed which links the DUPAL with other deep mantle geophysical anomalies, and utilizes a core/mantle boundary layer as a source of the DUPAL components. The low-degree mantle circulation is viewed as whole mantle quadrupolar convection, with equatorial upwelling; this serves to concentrate DUPAL components (and hotspots themselves) into the low-latitude regions.
The function of PP2A/B56 in non‐metazoan multicellular development

Abstract DB56, the Dictyostelium B56 homolog, displayed high sequence homology to other eukaryotic B56 subunits of the PP2A and a specific association with the PP2A catalytic subunit. Cells lacking DB56, psrA−, displayed higher PP2A phosphatase activity compared with the wild type, ∼10 hr of delayed expression of ecmA and ecmB prestalk markers, and inefficient culmination. The prespore marker cotB declined as wild-type cells culminate, but no such decline was observed from psrA− cells. Interestingly, psrA− cells exhibited higher GSK3 kinase activity. Furthermore, the expression of the dominant negative GSK3 mutant (K84/85M) in psrA− cells improved both prestalk and prespore expression patterns similarly to wild-type cells. However, culmination was not restored in psrA− cells expressing dominant negative GSK3, which suggests that PP2A/DB56 has an extra target during terminal differentiation. This report shows that PP2A/DB56 controls not only metazoan development, but also non-metazoan cell fate decision processes.
Methicillin‐Resistant Staphylococcus aureus Burden in Nursing Homes Associated with Environmental Contamination of Common Areas

Objectives: To determine whether environmental cleaning and contamination are associated with variation in the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) between nursing homes. Design: Prospective study of environmental contamination and cleaning quality. Setting: Nursing home. Participants: Ten California nursing homes. Measurements: Nursing homes were categorized into two groups based upon high and low differences in MRSA point prevalence and admission prevalence (delta prevalence) from nares screenings of nursing home residents. Environmental cleaning and infection control practices were evaluated by culturing common area objects for MRSA, assessing removal of intentionally applied marks visible only under ultraviolet (UV) light, and administering surveys on infection control and cleaning. Results: Overall, 16% (78/500) of objects were MRSA positive, and 22% (129/577) of UV-visible marks were removed. A higher proportion of MRSA-positive objects was found in the high (19%) than in low (10%) nursing home groups (P = .005). Infection control and cleaning policies varied, including the frequency of common room cleaning (median 2.5 times daily, range 1�3 times daily) and time spent cleaning per room (median 18 minutes, range 7�45 minutes). In multivariate models, MRSA-positive objects were associated with high delta prevalence nursing homes (odds ratio (OR) = 2.8, P = .005), less time spent cleaning each room (OR = 2.9, P < .001), and less-frequent cleaning of common rooms (OR = 1.5, P = .01). Conclusion: Substantial variation was found in MRSA environmental contamination, infection control practices, and cleaning quality. MRSA environmental contamination was associated with greater differences between MRSA point and admission prevalence, less-frequent common room cleaning, and less time spent cleaning per room, which suggests that modifying cleaning practices may reduce MRSA environmental contamination and burden in nursing homes.
A Research Approach for Tracking Local Economic Conditions in Small-Town America

This article describes a practical, low-cost research approach for tracking economic conditions in a small community. The federal government and even some state and large city governments have already addressed this issue with national and regional economic forecasts. But what about the fate of small, isolated metropolitan areas? National and regional forecasts that provide information of a macro nature do not contain data relevant to businesses in a small community. This article describes an approach used in a small Pennsylvania community that has employed a longitudinal study of local economic conditions extending over the past 8 years. The information obtained from this study has proven beneficial to local businesses, economic development agencies, elected officials, and others who are involved in improving the economic health of the community. The approach is technically and financially within reach of local organizations with modest research budgets and can be adapted readily to help other small comm...
Allergic rhinitis: Options for pharmacotherapy and immunotherapy

PREVIEWA trial of allergy medication can be both diagnostic and therapeutic in a patient with suspected allergic rhinitis, but with so many treatment options, it is sometimes difficult to know where to start. In this second of two articles on allergic rhinitis, Dr Ferguson provides information on efficacy and costs for various allergy drugs and discusses when to consider immunotherapy. The first article, beginning on page 110, discusses signs, symptoms, and triggering allergens.
Prediction of Reduced Ion Mobility Constants of Organic Compounds from Molecular Structure

Quantitative structure−property relationships (QSPRs) are used to develop mathematical models that accurately predict the reduced ion mobility constants (K0) for a set of 168 organic compounds directly from molecular structure. The K0 values are taken from an unpublished database collected by G. A. Eiceman, Chemistry Department, New Mexico State University. The data were collected using a Graseby Ionics environmental vapour monitor (EVM) gas chromatography/ion mobility spectrometer. Standardized conditions with controlled temperature, pressure, and humidity were used, and 2,4-lutidine was used as an internal standard. K0 values were measured for all monomer peaks. The best model was found with a feature selection routine which couples the genetic algorithm with multiple linear regression analysis. The set of six descriptors was also analyzed with a fully connected, feed-forward neural network. The model contains six molecular structure descriptors and has a root-mean-square error of about 0.04 K0 unit. Th...
Change detection in temporally evolving computer networks: A big data framework

The focus of this paper is to utilize a big data framework to characterize the behavior of central nodes over time in order to detect changes in large evolving computer networks. Changes in large evolving networks may indicate potential events such as cyber attacks, network failures or major shifts in network usage due to current events. Our approach entails the use of big data processing techniques such as MapReduce, to monitor central nodes to determine Consistency and Inconsistency (CoIn) in their availability and degree centrality across time periods. We also identify the Time Periods of Change (TPC) associated with CoIn. We present experimental results using real world internet traffic trace data, which indicates the potential of our approach to efficiently combine distributed processing techniques such as MapReduce to identify patterns of deviations.
Sources of chloride in hydrothermal fluids from the Valles caldera, New Mexico: a 36Cl study

The Valles caldera in New Mexico hosts a high-temperature geothermal system, which is manifested in a number of hot springs discharging in and around the caldera. In order to determine the fluid pathways and the origin of chloride in this system, we measured 36Cl/Cl ratios in waters from high-temperature drill holes and from surface springs in this region. The waters fall into two general categories: recent meteoric water samples with low Cl− concentrations (< 10 mg/L) and relatively high 36Cl/Cl ratios [(300–1000) × 10−15]; and geothermal brines with high Cl− concentrations (800–9400 mg/L) but low 36Cl/Cl ratios [(11–26) × 10−15]. The 36Cl/Cl ratios for meteoric waters are slightly higher than expected for this region, suggesting a small addition of anthropogenic 36Cl. Because of low 36Cl/Cl ratios and high Cl− concentrations in the brines, chloride in these waters must be derived from subsurface sources. A comparison between the observed 36Cl/Cl ratios in the brines and those calculated for potential source formations in this region indicates that the present host formations, mainly volcanic tuffs, cannot be major sources of chloride, and that formations at greater depth, such as the Paleozoic and Precambrian formations are more likely to be sources of chloride in the brines. The results suggest that brines are meteoric waters which penetrated into the basement where they derive chloride from leaching of basement rocks and/or from saline pore fluids trapped there, along with likely addition of chloride from Paleozoic strata. Although these fluids have since come to reside in the intracaldera volcanic sequence after convective upwelling, they do not derive much Cl− from the volcanic strata; and residence times of fluids in the volcanics are < 100,000 years.
Sex hormone-binding globulin, oligomenorrhea, polycystic ovary syndrome, and childhood insulin at age 14 years predict metabolic syndrome and class III obesity at age 24 years.

Objective We hypothesized that oligomenorrhea (menstrual cyclicity ≥42 days), hyperandrogenism, low levels of sex hormone-binding globulin (SHBG), childhood insulin, and metabolic syndrome (MetS) at age 14 years would predict MetS and class III obesity (body mass index ≥40 kg/m 2 ) at age 24 years. Study design In this prospective study of schoolgirls, at age 14 years, the girls were categorized as regularly cycling (n = 375), oligomenorrheic (n = 18), or oligomenorrhea plus biochemical hyperandrogenism (polycystic ovary syndrome [PCOS]; n=12), together designated PCOS. Results Significant explanatory variables for MetS at age 24 years included childhood insulin, MetS, and PCOS category (all positive) and SHBG (negative) at age 14 years. Using categorical data, top decile of childhood insulin, MetS at age 14, bottom decile of SHBG, and PCOS category were significant positive predictors for MetS at age 24. SHBG (negative), black race (positive), and oligomenorrhea (positive) were significant explanatory variables for class III obesity at age 24. Using categorical data, black race, MetS at age 14, bottom decile of SHBG, PCOS category, and top decile of childhood insulin were positive explanatory variables for class III obesity at age 24 years. Conclusions Oligomenorrhea, PCOS (a subcohort of oligomenorrhea), hyperandrogenism, low SHBG, MetS, and childhood insulin at age 14 years may represent a critical, reversible pathway for the development of MetS and class III obesity in young adulthood.
Determination of the dynamical behaviour of biological materials during impact using a pendulum device

Abstract A pendulum device has been developed to measure contact force, displacement and displacement rate of an impactor during its impact on the sample. Displacement, classically measured by double integration of an accelerometer, was determined in an alternative way using a more accurate incremental optical encoder. The parameters of the Kuwabara–Kono contact force model for impact of spheres have been estimated using an optimization method, taking the experimentally measured displacement, displacement rate and contact force into account. The accuracy of the method was verified using a rubber ball. Contact force parameters for the Kuwabara–Kono model have been estimated with success for three biological materials, i.e., apples, tomatoes and potatoes. The variability in the parameter estimations for the biological materials was quite high and can be explained by geometric differences (radius of curvature) and by biological variation of mechanical tissue properties.
Learning to teach in a field-based methods course: The development of pedagogical content knowledge

Abstract This study describes what and how seven preservice teachers learned during a field-based elementary physical education methods course. Observations of all classes, interviews, and the preservice teachers' written work were data sources. An ecological approach to perception and action was used to interpret the data. All seven preservice teachers discussed the development of pedagogical content knowledge as salient. Development was described as increased differentiation in terms of individual/task/environment relations. Preservice teachers linked inadequate pedagogical content knowledge to problems observing and teaching, and connected knowledge development to improved observing and teaching. It was evident that pedagogical content knowledge included experiential dimensions.
Interaction of bacteria and host cell walls: its relation to mechanisms of induced resistance

Abstract Cells of avirulent (B1) and incompatible (S210) strains of Pseudomonas solanacearum attach readily to the walls of tobacco mesophyll cells. By 4 h after infiltration of tobacco leaves with 10 8 bacterial cells/ml, fibrillar and granular material extruded from the host cell walls and bound by the outer wall layer envelop the attached bacteria. At the site of attachment, the host cell wall is frequently eroded, the plasmalemma separates from the cell wall and becomes convoluted and numerous membrane-bound vesicles accumulate in the space between the plasmalemma and the cell wall. With these bacteria, a hypersensitive reaction (HR) develops by 6 to 12 h after infiltration; as a result, the host cell collapses and organelles are deranged. In contrast, virulent strains of the pathogen (K60) are not attached and remain free to multiply in the intercellular fluid, causing no visible changes in organelle structure during the first 12 h after infiltration. Saprophytic bacteria ( Bacillus subtilis, Escherichia coli ) are attached and enveloped, but do not cause a visible HR. When heat-killed B1 cells are infiltrated into tobacco leaves, the dead bacteria attach in the same manner as avirulent, live cells and the initial host cell responses that envelop the bacteria are observed, but there is no cell collapse. After 24 h, challenge inoculation of the pretreated leaves with 10 8 live B1 cells/ml does not result in the HR and these bacteria do not attach to and are not enveloped by the host cell walls. Prevention of the HR appears to be related to this lack of attachment to the host cell walls.
Predicting changes in neuronal excitability type in response to genetic manipulations of K + -channels

The way a neuron undergoes rest-spiking transitionsdetermines the type of excitability and the computationalproperties of a neuron. Such transitions are particularlyimportant in the motor system, specifically with respect tomotor-unit recruitment and gradation of force. If weregard the electrophysiological activity of a neuron as adynamical system, the rest-spiking transition can bethought of as a bifurcation. That is, a qualitative change inthe trajectories followed by the variables in the system.Recordings from Drosophila neurons show that the spik-ing activity of a neuron undergoes qualitative changes asoccurs after genetic manipulations that affect the popula-tion of potassium channels [1]. We developed a singlecompartment model of the dynamics of the identifiedmotor neuron MN5 from Drosophila based on publishedexperimental results [2]. In vivo, MN5 controls the dorsal-longitudinal fiight muscle, firing trains of action poten-tials with a frequency between 6 and 25 Hz depending onthe excitatory drive it receives. Bifurcation studies wereperformed to elucidate the changes in phase space as afunction of different biophysical parameters includinghalf activation potentials, gating charge, close-open ratesand number of membrane channels. Bifurcation analysisand simulations predict that the number of channels andthe half-activation potential for the delayed rectifiers andA-type potassium channels can explain changes in spikingbehavior resulting from genetic manipulations asreported in [1,2]. For instance, decreasing the half activa-tion potential for the delayed rectifier channel induces achange in bifurcation from saddle-node (no subthresholdoscillations before spiking) to Hopf (subthreshold oscilla-tions before sustained spikes). Biophysical parametersobtained from MN5 patch clamp recordings will be usedin the future to restrict the parameter space specifically forMN5. The theoretical results from this study can be testedusing targeted genetic manipulations of potassium chan-nels.
Subcooled Pool Boiling Experiments on Horizontal Heaters Coated With Carbon Nanotubes

Pool boiling experiments were conducted with three horizontal, flat, silicon surfaces, two of which were coated with vertically aligned multiwalled carbon nanotubes (MWCNTs). The two wafers were coated with MWCNT of two different thicknesses: 9 μm (Type-A) and 25 μm (Type-B). Experiments were conducted for the nucleate boiling and film boiling regimes for saturated and subcooled conditions with liquid subcooling of 0―30°C using a dielectric fluorocarbon liquid (PF-5060) as test fluid. The pool boiling heat flux data obtained from the bare silicon test surface were used as a base line for all heat transfer comparisons. Type-B MWCNT coatings enhanced the critical heat flux (CHF) in saturated nucleate boiling by 58%. The heat flux at the Leidenfrost point was enhanced by a maximum of ∼150% (i.e., 2.5 times) at 10°C subcooling. Type-A MWCNT enhanced the CHF in nucleate boiling by as much as 62%. Both Type-A MWCNT and bare silicon test surfaces showed similar heat transfer rates (within the bounds of experimental uncertainty) in film boiling. The Leidenfrost points on the boiling curve for Type-A MWCNT occurred at higher wall superheats. The percentage enhancements in the value of heat flux at the CHF condition decreased with an increase in liquid subcooling. However the enhancement in heat flux at the Leidenfrost points for the nanotube coated surfaces increased with liquid subcooling. Significantly higher bubble nucleation rates were observed for both nanotube coated surfaces.
Provider Choice: Essential To Autonomy or Advertising Gimmick?

Free choice of provider is heralded as a right of autonomy, but the goals of autonomy are better served in today's health care environment when there is informed choice of the care delivery system. The principle of liberty is distinguished from respect for autonomy. Free choice of provider would be demanded only by liberty, except that allocation of health care resources does not meet criteria for the application of liberty. Patients attempting to choose the best practitioner do not have data to support the decision. If data were available, access to these superior practitioners would become an allocation problem. A mythology of the wise practitioner fosters the concept of provider choice as a personal judgement about clinical knowledge. The emerging trends of collaborative care, standardization of practice guidelines and diversity of delivery systems among reimbursers create a situation where a patient's autonomy to choose goals for treatment is respected through the choice of delivery system.
Research to Production: Lessons Learned from an Innovative Information System Development Approach

The development and delivery of large-scale, complex information systems is difficult, resulting in a low success rate industry-wide. Most production information systems are developed with the use of a top-down approach often called the waterfall model. In developing a complex information system, many variables must be considered and many potential solutions evaluated simultaneously; a linear approach is not conducive to this activity. Also, projects of this scale and complexity can be disruptive and unmanageable in a production environment. The research and development (R&D) environment is better suited to address the challenges presented by these kinds of projects. Development and transfer should not be considered separately, because the former will have a significant effect on the latter. Development in an R&D environment can provide important advantages for ensuring a successful transfer. A realworld case study of transferring an archived data management system from research to production is used to h...
A prospective study of immune responsiveness in human melanoma. I. Assessment of initial pretreatment status with stage of disease.

The clinical findings in 262 patients with melanoma were correlated with an assessment of their cellular-mediated immunity by delayed-type hypersensitivity (DTH) skin tests, by lymphocyte blastogenesis, and by leukocyte enumerations. Patients with systemic metastases (stage IV) and those with evidence of tumor burden had fewer positive DTH reactions for recall antigens than did patients with localized disease (stage I), patients with no evidence of tumor burden, and 227 normal controls. However, no differences were found in the magnitude of response among patients with melanoma or when compared with controls. Patients with melanoma had fewer responses to dinitrochlorobenzene (40%) than did controls (98%), but there were no differences by stage or tumor burden. Similarly, blastogenesis in the presence of PHA, Con A, and PWM was depressed when compared with controls, but there was no meaningful correlation with the clinical status. Leukocyte, T cell, or B cell counts revealed no alteration from normal for the patients with melanoma. The usefulness of these studies for routine clinical monitoring is questioned.
Resistance of monkeys to aerosol administration of purified cholera enterotoxin.

Abstract Four species of monkey were exposed for periods of 27–30 min to aerosols generated from 20 mg of highly purified cholera enterotoxin. None of the monkeys died after exposure to doses of toxin between 85 and 311 μg/kg. These results suggest that the cholera enterotoxin is not easily transported into the circulatory system via the respiratory route.
Ion Torrent sequencing for conducting genome-wide scans for mutation mapping analysis

Mutation mapping in mice can be readily accomplished by genome wide segregation analysis of polymorphic DNA markers. In this study, we showed the efficacy of Ion Torrent next generation sequencing for conducting genome-wide scans to map and identify a mutation causing congenital heart disease in a mouse mutant, Bishu, recovered from a mouse mutagenesis screen. The Bishu mutant line generated in a C57BL/6J (B6) background was intercrossed with another inbred strain, C57BL/10J (B10), and the resulting B6/B10 hybrid offspring were intercrossed to generate mutants used for the mapping analysis. For each mutant sample, a panel of 123 B6/B10 polymorphic SNPs distributed throughout the mouse genome was PCR amplified, bar coded, and then pooled to generate a single library used for Ion Torrent sequencing. Sequencing carried out using the 314 chip yielded >600,000 usable reads. These were aligned and mapped using a custom bioinformatics pipeline. Each SNP was sequenced to a depth >500×, allowing accurate automated calling of the B6/B10 genotypes. This analysis mapped the mutation in Bishu to an interval on the proximal region of mouse chromosome 4. This was confirmed by parallel capillary sequencing of the 123 polymorphic SNPs. Further analysis of genes in the map interval identified a splicing mutation in Dnaic1 c.204+1G>A, an intermediate chain dynein, as the disease causing mutation in Bishu. Overall, our experience shows Ion Torrent amplicon sequencing is high throughput and cost effective for conducting genome-wide mapping analysis and is easily scalable for other high volume genotyping analyses.
Damage detection and diagnosis of composites using built-in piezoceramics

An investigation was performed to develop a technique for using built-in piezoelectrics to detect delaminations and to estimate their size and location in laminated composite structures. Both experimental and analytical work were conducted in the study. Piezoceramics were utilized as sensors for receiving signals and as actuators for dispatching diagnostic waves. A diagnostic technique was developed which combines an electromechanical structural model with an iterative damage identification algorithm to form a closed loop. The structural model was used to predict the frequency response of normal and delaminated structures excited by actuators. The identification algorithm compares the calculation with the data to find a best estimate of delamination size and location. The technique first compares the measured dynamic response to a baseline. If they disagree, the technique searches through the possible locations and sizes of delaminations using the structural model and compares the results with the measurements. The loop terminates when the calculated and the measured frequency responses agree. Tests on composite beams with implanted delaminations were conducted to verify the model and predictions. Overall, the predictions agreed with the data.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Potentiation of leukotriene formation in pulmonary and vascular tissue

Leukotriene (LT) release from vascular and pulmonary tissue was assessed by a radioimmunoassay for peptide leukotrienes (i.e., LTC4, LTD4 and LTE4). The calcium ionophore A-23187 at 1-3 micrograms/ml and platelet activating factor (PAF) at 10 micrograms/ml produced marked formation of peptide leukotrienes in minced cat pulmonary tissue. This was also confirmed by bioassay of the incubates in isolated perfused cat coronary arteries. Rat pulmonary tissue was comparable to cat with regard to LT production, but guinea-pig lung produced about 30-50% less on a weight basis. In addition, aortic and coronary artery vessel walls produced significant amounts of LTs. The time course for maximal leukotriene production occurred at 45-60 min of incubation at 37 degrees C in both the radioimmunoassay and the bioassay. Cat coronary artery constricted markedly to LTC4 or LTD4 (30-40 mm Hg) and to the lung or blood vessel incubate. This constriction was virtually totally blocked by the leukotriene antagonist FPL-55712, but not by the thromboxane receptor antagonist, pinane thromboxane A2, the alpha-adrenergic receptor antagonist, phenoxybenzamine, or the angiotensin receptor antagonist, saralasin. Thus, pulmonary and vascular tissue produce leukotrienes that appear to exert coronary constrictor effects on specific leukotriene receptors. These results indicate that the ischemia of shock and anaphylaxis may be accentuated by the release of peptide leukotrienes.
Interaction of the Antitumor Compound Cryptophycin-52 with Tubulin†

Cryptophycin-52 (LY355703) is currently undergoing clinical evaluation for cancer chemotherapy. It is a potent suppresser of microtubule dynamics in vitro, and low picomolar concentrations appear to inhibit cancer cell proliferation at mitosis by stabilizing spindle microtubules. In the present study, using [3H]cryptophycin-52, we found that the compound bound to tubulin at a single high-affinity site [apparent Ka (3.6 ± 1) × 106 L/mol, 34 °C]. The binding of cryptophycin-52 to tubulin was rapid, not appreciably temperature-dependent, and very poorly reversible. However, we could remove [3H]cryptophycin-52 from [3H]cryptophycin-52−tubulin complex by denaturing the complex with either urea treatment or boiling. These data suggest that the binding of cryptophycin-52 to tubulin is not covalent. A van't Hoff plot of the binding data indicated that the binding of cryptophycin-52 to tubulin is primarily entropy-driven with a minimum enthalpy contribution. In addition, cryptophycin-52 perturbed the far-ultraviol...
Large-grain polycrystalline silicon films with low intragranular defect density by low-temperature solid-phase crystallization without underlying oxide

The solid-phase crystallization of an amorphous silicon film to polycrystalline silicon by a low-temperature (⩽600 °C) furnace anneal has been investigated in a suspended cantilever structure without underlying silicon oxide by transmission electron microscopy and Raman spectroscopy. The grain size of polysilicon increases up to ∼3.0 μm and the density of intragranular defects decreases one order of magnitude in the samples without underlying oxide, compared with those with underlying oxide. The main reasons for the high quality of the suspended structures are thought to be due to the lower stress in the films during crystallization and a reduced grain nucleation rate.
Effects of CaO on the Strength and Toughness of AIN

Fully dense, undoped AIN is found to have the following average mechanical properties: hardness, 12.2 GPa; strength, 377 MPa; and fracture toughness (based on the fracture load sustained by indented disks), 3.6 MPa·m½. The addition of 2 wt% CaO to AIN changes the fracture mode from transgranular to intergranular while concurrently decreasing the hardness, strenght, and toughness. Increasing the grain size of CaO-doped AlN decreases strength and increases toughness. Toughness estimates based on the fracture load sustained by indented disks are about twice the value determined for crack extension after indentation.