cssi/SciSciGPT-SciSciNet huggingface dataset:
A Depositional Model for the Linton tetrapod Assemblage (Westphalian D, Upper Carboniferous) and its Palaeoenvironmental Significance

A palaeoenvironmental study indicates that fossils from the famous Upper Carboniferous vertebrate deposit of Linton, Ohio, are preserved in an allochthonous organic filling of an abandoned river channel. A depositional model developed from this analysis is corroborated by other Coal Measure vertebrate localities in Europe that also appear to represent abandoned channels. Additional vertebrate occurrences were discovered in the Ohio Valley by prospecting coal-bearing intervals for similar channel deposits. These results suggest that environmental models based on study of geological controls influencing fossil concentrations, combined with information on collecting histories of classic sites, offer an improved understanding of seemingly extraordinary assemblages and a means by which further fossiliferous deposits may be located.
Evaluation of a family planning program for individuals with mental retardation.

An evaluation was conducted to answer the question: Can a specially designed program for women with mental retardation increase the use of birth control methods? Results indicate there was a significant shift to permanent birth control for the treatment group, from 42.5 percent at baseline to 68.0 percent after one year. The results suggest that an intensive, individually designed prevention program can reduce the occurence of unwanted pregnancies for women with mental retardation.
Screening and designing patchy particles for optimized self-assembly propensity through assembly pathway engineering

Self-assembly holds promise for creating new materials and devices because of its inherent parallelism, allowing many building blocks to simultaneously organize using preprogrammed interactions. An important trend in nanoparticle and colloid science is the synthesis of particles with unusual shapes and/or directional (“patchy”) interactions, whose anisotropy allows, in principle, assemblies of unprecedented complexity. However, patchy particles are more prone to long relaxation times during thermodynamically driven assembly, and there is no a priori way of predicting which particles might be good assembly candidates. Here we demonstrate a new conceptual approach to predict this information using sequences of intermediate clusters that appear during assembly. We demonstrate our approach on a family of model building blocks as well as a real system of CdTe/CdS tetrahedra and find design rules for engineering the optimized assembly of target structures.
Effects of mechanical drawing on gas transport in an emulsion acrylic multipolymer

A study was conducted on the gas sorption and transport properties of a multiphase commercial acrylic polymer trade-named Korad ACV before and after subjecting the polymer to mechanical drawing operations. The Korad system is an emulsion-polymerized amorphous composite comprised of a glassy, predominantly PMMA matrix phase and a ply(butyl acrylate)-dispersed phase surrounded by a PMMA/PBA copolymer shell. Large increases (up to eightfold) in permeability P to several gases were observed upon drawing Korad. The observed changes in the permeability to He, Ar, N2, and CH4 on drawing were correlated with the draw ratio, drawing temperature, and molecular diameter of the gas penetrant. Most of the increase in permeability occurred at low draw ratios (1–2). The increases in P were most dramatic for drawing temperatures below or near the Tg of the matrix phase (about 90°C) and were quite small for drawing temperatures 30°C or more above the matrix Tg. The extent of the permeability increase also depended on the gas, being greatest for CH4 and essentially imperceptible for He. The changes in permeability behavior were interpreted in terms of a morphological transformation in the phase of the drawn Korad, which causes the originally dispersed rubber particles to assume a more continuous character. The behavior of the composite was modeled by the Takayanagi and Nielson treatments of two-phase composite systems. Volumetric, thermal, mechanical, and viscoelastic properties were measured for the as-received and processed Korad films to elucidate physical changes in the drawn polymer.
Myoglobin synthesis studiedin vitro in the chick embryo

Summary Chick embryos (as young as Hamburger-Hamilton stages 4–6) and their isolated body parts were capable of myoglobin synthesis, when measured with anin vitro system using incorporation of lysine-U-14C into precipitates formed with specific antimyoglobin serum. Crude minces and homogenates were capable of continuing this incorporation for 5–7 hours. Myoglobin, as well as total soluble protein, synthetic ability increased with advancing age, most strikingly between age 2 and 4 daysin ovo. Older embryos failed to demonstrate continuing increases in myoglobin synthetic ability, while they did increase their capacity for production of total soluble proteins. Approximately 7–8% of total soluble protein synthesis of 1-day-old embryos was detectable as incorporation into myoglobin, while only about 1% of total soluble protein synthesis of 7-day-old embryos could be accounted for as myoglobin production. Most myoglobin synthesis in the 1-day-old embryo (60%) occurred in the head region. With age, the head became relatively less important as a site of myoglobin synthesis. The cardiac area maintained a relatively constant portion of the total body myoglobin synthesis, approximately 25%, while the proportion which occurred in the hind-body region rose with increasing age. There was a reduction in the ratio of myoglobin to protein synthesis in each of the chick body parts with age. This was most prominent, however, in the head and midbody regions and was due to a greater relative synthesis of proteins other than myoglobin by these embryo parts.
EUS-guided portal vein catheterization and pressure measurement in an animal model: a pilot study of feasibility.

Abstract Background The extrahepatic portal vein is inaccessible to direct catheterization. Methods Because EUS can readily image the portal vein, the feasibility of EUS-guided portal vein catheterization by using a 22-gauge needle was studied in 7 normal pigs and 14 pigs in which portal hypertension was induced (7/14 anticoagulated). Results Catheterization was not possible by EUS or transhepatic methods in, respectively, 3 and 5 animals. One anticoagulated animal had a small amount of periduodenal bleeding as a result of EUS catheterization. The mean normal portal vein pressure (1 standard deviation) as determined by EUS and transhepatic methods was, respectively, 20.3 (4) mm Hg and 20.4 (2) mm Hg. Injection of polyvinyl alcohol particles increased the portal vein pressure by 10.2 (11.59) mm Hg. There was a close correlation under all conditions between the mean portal vein pressures obtained by EUS and transhepatic catheterization (r=0.91). Conclusions EUS-guided portal vein catheterization appears to be feasible in an animal model and provides accurate pressure measurements.
Effect of Resistant and Digestible Starch on Intestinal Absorption of Calcium, Iron, and Zinc in Infant Pigs

The first nonmilk foods that are given to infants contain high levels of starch, a fraction of which is resistant to enzyme hydrolysis. Incomplete digestion of starch may interfere with the absorption of certain minerals. A fraction of dietary starch which is resistant to in vitro enzymatic hydrolysis has been termed resistant starch. The aim of this study was to compare the intestinal apparent absorption of calcium, phosphorus, iron, and zinc in the presence of either resistant or digestible starch. Twelve 7-10-d-old piglets were fitted with a T-tube inserted into the intestine approximately 3 m distal to the duodenum. Animals received in random order 200 mL of a test meal of cooked, cooled, high amylose corn starch (16.4% resistant starch), or cooked rice starch (digestible starch) administered by an orogastric tube. Both meals contained the same amount of calcium, phosphorus, iron, and zinc. The test meal also contained tracer amounts of 59Fe and 65Zn, as well as polyethylene glycol 3350, as a nonabsorbable marker. Intestinal apparent absorption of starch was greater the meal with digestible starch (71.0 +/- 17.0%) than after the meal with resistant starch (49.2 +/- 10.3) (p < 0.001). After feeding the meals with resistant and digestible starch, mineral apparent absorption was, respectively: calcium, 40.2 +/- 11.8% versus 28.1 +/- 16.4% (p < 0.05); phosphorus, 73.2 +/- 14.0% versus 67.8 +/- 18% (NS); iron, 24.1 +/- 12.2% versus 12.6 +/- 10.6% (p < 0.01), and zinc, 35.0 +/- 13.0% versus 30.6 +/- 8.22% (NS). In conclusion, a meal containing 16.4% resistant starch resulted in a greater apparent absorption of calcium and iron compared with a completely digestible starch meal. If this finding holds true for the whole bowel, administration of resistant starches could have a positive effect on intestinal calcium and iron absorption.
Breast cancer prevention strategies for the twentieth century

The incidence of breast cancer has reached epidemic proportions in most Western developed countries. The breast cancer rate is three times higher than in developing countries. In the USA alone, one in eight women will develop breast cancer during her lifetime. Molecular medicine has allowed us to make great advances in understanding disease susceptibility and pathogenesis. It has also let us forge inroads into the genetic screening of women who have a family history of breast cancer. However, women who have been classified as members of the high-risk groups have expectations of effective prevention or prophylactic therapy that cannot, as yet, be delivered. It is time to give serious consideration to the emerging prophylactic strategies that take advantage of the advances in molecular techniques in order to address this deficit.
Specific resistivity of the cerebral cortex and white matter

Abstract Electrical resistance of the cortex and white matter of the cat was investigated by comparing the resistivity with that measured from solutions of known conductivities. At 36 C it was found that the specific resistance of the cortex is 556 ± 45 (SD) ohm cm and of the white matter, 580 ± 53 (SD) ohm cm.
Solution structure of the aminofluorene [AF]-external conformer of the anti-[AF]-C8-dG adduct opposite dC in a DNA duplex

The Escherichia coli genome contains a C-G1-G2-C-G3-C-C NarI hot spot sequence for −2 deletion mutations at G3 by aromatic amine carcinogens 2-acetylaminofluorene (AAF) and 2-aminofluorene (AF) that form covalent adducts at the C8-position of the guanine ring. Each of the three guanines are positioned in different sequence contexts (C-G1-G, G-G2-C, and C-G3-C) which provides an opportunity to investigate the potential sequence dependent interconversion between AF-intercalated and AF-external conformers of the [AF]dG adduct positioned opposite dC within the NarI sequence at the duplex level. We have prepared and purified DNA duplexes containing the [AF]dG adduct positioned in C-[AF]G-G, G-[AF]G-C, and C-[AF]G-C NarI sequence contexts and observe the ratio of AF-intercalated to AF-external conformers to be 30:70, 10:90, and 50:50, respectively. We have applied a combined NMR-molecular mechanics approach to define the structure of the AF-external conformer in the G-[AF]G-C NarI sequence context where it is t...
Constraining Supersymmetric Dark Matter With Synchrotron Measurements

The annihilations of neutralino dark matter (or other dark matter candidate) generate, among other standard model states, electrons and positrons. These particles emit synchrotron photons as a result of their interaction with the galactic magnetic field. In this paper, we use the measurements of the Wilkinson Microwave Anisotropy Probe satellite to constrain the intensity of this synchrotron emission and, in turn, the annihilation cross section of the lightest neutralino. We find this constraint to be more stringent than that provided by any other current indirect detection channel. In particular, the neutralino annihilation cross section must be less than $\ensuremath{\approx}3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}26}\text{ }\text{ }{\mathrm{cm}}^{3}/\mathrm{s}$ ($1\ifmmode\times\else\texttimes\fi{}{10}^{25}\text{ }\text{ }{\mathrm{cm}}^{3}/\mathrm{s}$) for 100 GeV (500 GeV) neutralinos distributed with a Navarro-Frenk-White halo profile. For the conservative case of an entirely flat dark matter distribution within the inner 8 kiloparsecs of the Milky Way, the constraint is approximately a factor of 30 less stringent. Even in this conservative case, synchrotron measurements strongly constrain, for example, the possibility of wino or Higgsino neutralino dark matter produced nonthermally in the early universe.
Queueing behaviour of two interconnected buffers of a packet network with application to the evaluation of packet routeing policies

In this paper, the behaviour of two interconnected nodes of a packet communication network is analysed. The packet arrival process to the first node is described by an i.i.d. discrete time process. The packet arrival process to the second node consists of two mutually independent streams; one stream carries the packet output process from node 1; the other stream carries a packet traffic described by a dependent discrete time process. For this system, the following quantities are derived: (a) the first two moments of the buffer occupancy and the mean packet delay in the first node; (b) a description of the packet output process of the first node; (c) the first two moments of the buffer occupancy and the mean packet delay in the second node. In the sequel, the behaviour of the buffers is investigated under some simple routeing policies in node 1. The objective at this point is to evaluate the queueing behaviour of both buffers under some routeing policies and it is not to seek for the optimal packet routeing policy in the first node. It is shown how the routeing policy in node 1 can be incorporated in the description of the packet output process of node 1 and, then, the behaviour of buffer 2 be accurately evaluated. The numerical results show that the queueing behaviour of buffer 2 cannot be accurately evaluated by incorporating a Bernoulli approximation on the output process of node 1. Furthermore, it is shown that different routeing policies in the first node result in different intensities of the queueing problems in the second node, although the packet output rate from the first node is constant for all routeing policies considered. It turns out that a routeing policy which best randomizes the packet output process results in the least significant queueing problems in the second node. The latter implies that routeing decisions should be based not only on the desired packet traffic rates (which achieve optimality in the load distribution among the nodes), but also on the packet randomization affect of the routeing policy considered.
The fragmentation of metastable NH+3 ions and isotopic analogs: an example of tunneling through a rotational barrier

The fragmentation of metastable NH+3 ions and isotopic analogs via the reaction NH+3 → NH+2 + H has been investigated using mass analysed ion kinetic energy spectrometry (MIKES). Kinetic energy release distributions and the metastable intensity were measured as a function of ion source temperature. Both the average kinetic energy release and the metastable intensity increase with ion source temperature. The data are consistent with the metastable reaction arising from tunneling through a rotational barrier. The experimental data are compared with the predictions of a tunneling model.
Gray and Green Revisited: A Multidisciplinary Perspective of Gardens, Gardening, and the Aging Process

Over fourteen years ago, the concept of “gray and green” was first introduced by Wright and Lund (2000) to represent a new awareness and a call for increased scholarship at the intersection of environmental issues and the aging process. This review paper revisits that concept with a fresh perspective on the specific role of gardens and gardening in the aging experience. As example, gardening is one of the most popular home-based leisure activities in the US and represents an important activity in the lives of older adults in a variety of residential settings. Yet, there has been a lack of any comprehensive and multidisciplinary (science and humanities) examination of the nexus between gardening and the aging experience, and in particular with research connections to stewardship and caring. In this paper, we review contemporary articles demonstrating the multidisciplinarity of gardening and the aging process. First, we will focus on the beneficial psychological effects resulting from the cultivation of caring, including personal contentment and artistic expression. Second, we will focus on stewardship and how gardening increases health, community awareness, and a connection to future generations. On the surface, this may demonstrate a separation between the humanities and science, but we will clarify a symbiotic relationship between the two disciplines in our conclusion.
Molecular-crowding effects on single-molecule RNA folding/unfolding thermodynamics and kinetics.

The effects of “molecular crowding” on elementary biochemical processes due to high solute concentrations are poorly understood and yet clearly essential to the folding of nucleic acids and proteins into correct, native structures. The present work presents, to our knowledge, first results on the single-molecule kinetics of solute molecular crowding, specifically focusing on GAAA tetraloop–receptor folding to isolate a single RNA tertiary interaction using time-correlated single-photon counting and confocal single-molecule FRET microscopy. The impact of crowding by high–molecular-weight polyethylene glycol on the RNA folding thermodynamics is dramatic, with up to ΔΔG° ∼ −2.5 kcal/mol changes in free energy and thus >60-fold increase in the folding equilibrium constant (Keq) for excluded volume fractions of 15%. Most importantly, time-correlated single-molecule methods permit crowding effects on the kinetics of RNA folding/unfolding to be explored for the first time (to our knowledge), which reveal that this large jump in Keq is dominated by a 35-fold increase in tetraloop–receptor folding rate, with only a modest decrease in the corresponding unfolding rate. This is further explored with temperature-dependent single-molecule RNA folding measurements, which identify that crowding effects are dominated by entropic rather than enthalpic contributions to the overall free energy change. Finally, a simple “hard-sphere” treatment of the solute excluded volume is invoked to model the observed kinetic trends, and which predict ΔΔG° ∼ −5 kcal/mol free-energy stabilization at excluded volume fractions of 30%.
Slowing progression of early stages of AD with alternative therapies: A feasibility study

This pilot study identified the feasibility and efficacy of the effect of combining healing touch (HT) and body talk cortices (BTC) on the progression of Alzheimer's disease (AD). Both HT and BTC elicit the relaxation response and support cognitive function from two different perspectives. A two-group, repeated measures design was used. Subjects (n = 22), 65 or older with early stage (less than four) AD, residing in the community (n = 2) or in care agencies (n = 20), were assigned to either the HT-BTC group (n = 12) or the control group (n = 10) randomized by residence. The treatment group received, 6 months of weekly HT and performed the BTC technique daily. The usual medical regimen for all subjects was continued. The control group had no additional interventions. Both groups were assessed at baseline, 3 and 6 months. The groups did not differ significantly at baseline on cognitive reserve, age, gender, and ethnicity, nor on the outcome variables (cognitive function, mood, & depression). Adherence (76%) to the BTC protocol, the major feasibility problem, related to memory deficits. Significant interactions occurred regarding cognitive function and mood. Significant improvements in cognitive function (p = .008), mood (p = .001), and depression (p = .028) were observed in the treatment group which is not the usual course of AD. A decline in cognitive function occurred in the control group typical of AD's usual course. Although the number of subjects in this pilot study was small, and there were feasibility challenges with recruitment and adherence, important trends were noted suggesting areas for future study.
An arithmetical approach to the mechanics of blood flow in small caliber blood vessels.

Abstract The problem of theoretical investigation of the blood flow in small caliber blood vessels is a difficult one since the number of red blood cells occupying the cross-section of such a blood vessel is too small to treat the blood as a continuous fluid medium, and is too large to account for the motion of all individual particles. Consequently, it is necessary that a study of methodology providing an approach to the physics of the problem at hand precede the analysis. In order to provide a theoretical basis of the mechanics of blood flow in small blood vessels, such as the velocity profile, and the pressure-flow relationship, a mathematical model of the problem is presented and studied based on an arithmetical approach. The characteristics of the flow exhibited by the highly idealized model of the flow employed in this study are qualitatively similar to that of the blood flow in many respects.
A Poisson Fishing Model

A fishing model of Starr, Wardrop, and Woodroofe is related to the sequential search model of Cozzolino. The latter is generalized to allow an arbitrary joint distribution of capture times and fish sizes. Implications to the foraging models of Oaten and Green and to debugging software are indicated.
Mechanotransduction of rat aortic vascular smooth muscle cells requires RhoA and intact actin filaments

Abstract —The growth-promoting effect of mechanical stress on vascular smooth muscle cells (VSMCs) has been implicated in the progress of vascular disease in hypertension. Extracellular signal–regulated kinases (ERKs) have been implicated in cellular responses, such as vascular remodeling, induced by mechanical stretch. However, it remains to be determined how mechanical stretch activates ERKs. The cytoskeleton seems the most likely candidate for force transmission into the interior of the cell. Therefore, we examined (1) whether the cytoskeleton involves mechanical stretch–induced signaling, (2) whether Rho is activated by stretch, and (3) whether Rho mediates the stretch-induced signaling in rat cultured VSMCs. Mechanical stretch activated ERKs, with a peak response observed at 20 minutes, followed by a significant increase in DNA synthesis. Treatment with the ERK kinase-1 inhibitor, PD98059, inhibited the stretch-induced increase in DNA synthesis. Cytochalasin D, which selectively disrupts the network of actin filaments, markedly inhibited stretch-induced ERK activation. In the control state, RhoA was observed predominantly in the cytosolic fraction, but it was translocated in part to the particulate fraction in response to mechanical stretch. Botulinum C3 exoenzyme, which inactivates Rho p21 (known to participate in the reorganization of the actin cytoskeleton), attenuated stretch-induced ERK activation. Inhibition of Rho kinase (p160ROCK) also suppressed stretch-induced ERK activation dose dependently. Our results suggest that mechanotransduction in VSMCs is dependent on intact actin filaments, that Rho is activated by stretch, and that Rho/p160ROCK mediates stretch-induced ERK activation and vascular hyperplasia.
Outage Probability Analysis in a Cooperative UAVs Network Over Nakagami-m Fading Channels

The outage probability in a network of cooperative unmanned airborne vehicles (UAVs) is studied analytically. A master-slave topology with one ground control unit (GCU) is assumed where the GCU communicates directly with a master UAV. The master-slave and master-GCU links are assumed to satisfy a certain minimum data rate required by the application provided by the UAV. The outage probability of the system is defined as the probability that either the rate of transmission over any of the links drops below the predefined minimum value for that link, or the GCU-master link is not able to transmit the aggregate data from all UAVs besides the minimum rate achieved by the master UAV itself. The outage probability is considered over Nakagami-m fading channels. The resultant expression for the outage probability can be used to provide guidelines for system designers to minimize the outage probability of the cooperative UAVs network. In the same time, it could be used to maximize the system throughput with the constraint of not exceeding a certain outage probability limit.
Coherent activation of a synthetic mammalian gene network.

A quantitative analysis of naturally-occurring regulatory networks, especially those present in mammalian cells, is difficult due to their high complexity. Much simpler gene networks can be engineered in model organisms and analyzed as isolated regulatory modules. Recently, several synthetic networks have been constructed in mammalian systems. However, most of these engineered mammalian networks have been characterized using steady-state population level measurements. Here, we use an integrated experimental-computational approach to analyze the dynamical response of a synthetic positive feedback network in individual mammalian cells. We observe a switch-like activation of the network with variable delay times in individual cells. In agreement with a stochastic model of the network, we find that increasing the strength of the positive feedback results in a decrease in the mean delay time and a more coherent activation of individual cells. Our results are important for gaining insight into biological processes which rely on positive feedback regulation.
TWIN SCREW EXTRUSION OF PINK SALMON MUSCLE: EFFECT OF MIXING ELEMENTS AND FEED COMPOSITION

The effects of type of mixing element in the screw configuration and feed composition on specific mechanical energy input and product attributes during twin-screw extrusion were investigated. The mixing elements studied were kneading, reverse screw and combination of kneading and reverse screw elements. The feed composition was changed by altering the ratio of rice flour to pink salmon muscle. Incorporation of mixing elements increased the specific mechanical energy, and water solubility index; but decreased apparent density and Warner-Bratzler shear stress. Expansion ratio was maximum with kneading elements. However, reverse screw and combination produced extrudates with lesser expansion than that obtained using conveying screws with no mixing element. Increasing the fish solids content in the feed decreased specific mechanical energy, expansion ratio, and water solubility index; but increased the shear stress and apparent density. The shear stress for 0% and 30% fish solids blends were not affected in the expansion ratio range of 3 to 10. Water solubility index and shear stress were linearly related to specific mechanical energy and apparent density respectively.
Protein interfacial pocket engineering via coupled computational filtering and biological focusing criterion.

To engineer bio-macromolecular systems, pro- tein-substrate interactions and their configurations need to be understood, harnessed, and utilized. Due to the inherent large numbers of combinatorial configurations and confor- mational complexity, methods that rely on heuristics or stochastics, such as practical computational filtering (CF) or biological focusing (BF) criterions, when used alone rarely yield insights into these complexes or successes in (re)design- ing them. Here we use a coupled CF-BF criterion upon an amenable interfacial pocket (IP) of a protein scaffold complexed with its substrate to undergo residue replacement and R-group refinement (R 4 ) to filter out energetically unfavorable residues and R-group conformations, and focus in on those that are evolutionarily favorable. We show that this coupled filtering and focusing can efficiently provide a putative engineered IP candidate and validate it computa- tionally and empirically. The CF-BF criterion may permit holistic understanding of the nuances of existing protein IPs and their scaffolds and facilitate bioengineering efforts to alter substrate specificity. Such approach may contribute to accelerated elucidation of engineering principles of bio- macromolecular systems.
An Institutional Perspective on Prehispanic Maya Residential Variation: Settlement and Community at San Estevan, Belize

This article explores implications of a pattern of residential settlement found at the prehispanic Maya community of San Estevan in northern Belize. Although an awareness of the decision-making behavior of domestic groups helped to isolate the pattern, a household approach cannot by itself account for the overall community structure that emerged from the differential distribution of San Estevan's residential forms. Making sense of the organizational forces underlying this distribution requires a more comprehensive set of explanatory tools drawn from conceptualizations of institutions and their powers to shape the spaces of social practice.
Detection of polymer transition temperatures by infrared absorption spectrometry

Infrared bands in the 900–1100 cm−1 region are sensitive to thermal energy. These bands can result from intermolecular coupling, producing the crystal lattice, or from intramolecular coupling of the various atomic groups in a regular helix or coiled chain. In either case an increase in temperature will disrupt the coupling mode, resulting in a form of structural relaxation and a reduction in the integrated absorbance. It is proposed that the temperature at which the peak areas begin to decrease be assigned as the Tg. This is measured by continuously scanning a selected peak in the infrared spectrum of a polymer film while it is heated at a rate of about 1°C/min. Using this technique polyamides (nos. 6,66, and 610) exhibited transitions in the 30–50°C range, and by studying the increase in the free NH region (3440 cm−1) of nylon 66 two other transitions were detected at 80 and 137°C; the latter represents a change in the nylon 66 crystal state. An amorphous film of poly(ethylene terephthalate) displayed a transition at 58–68°C (Tg) and at 85°C, which is the crystallization temperature. Films of poly(vinyl acetate) and polystyrene exhibited transitions at 25–37°C and at 70°C, respectively.
Torsades de pointes: unanswered questions.

Torsade de pointes(Tdp)is a polymorphic ventricular tachycardia(VT)in which the axis of the QRS complex changes direction after a certain number of complexes as if the complex rotated around the baseline. Tdp is usually associated with QT prolongation and dispersion of ventricular repolarlization(DR). Experimental models of tdp are usually associated with induction of early after depolarizations(EADs). Several aspects of the pathogenesis of tdp are incompletely understood. The purpose of this article is to propose the directions in research that may increase our current understanding of the factors responsible for tdp. The most plausible hypotheses requiring further supporting evidence are :1 . The occurrence of tdp requires the presence of DR i.e. tdp does not occur in the absence of DR .2 . EADs appear to play an important role as a trigger to tdp in the animal models but more evidence are needed at the clinical level. 3. EADs may be responsible for arrhythmias other than tdp. 4. The greater incidence of tdp in the females than in tha males may be attributed to differences in the duration of the QT interval and different morphology of the ST‑segment and the T‑wave. The above gender differences may be caused by the effects of gonadal hormones which modulate some of the membrane currents flowing during early ventricular repolarization. (J Nippon Med Sch 2002; 69: 218―223)
Surface Current Determination from Electric-Fields Distribution Measurement

Determination of induced surface current on cylindrical reflectors in a parallel-plate region from measurements of electricfields distribution is described. The probe-reflector interaction in the measurement of electric-fields distribution is examined and the requirement of probe reflector spacing which ensure the small interaction is also investigated.
Reproducing Identity: Using Images to Promote Pronatalism and Sexual Endogamy among Tibetan Exiles in South Asia

In this paper the authors analyze images from publications, produced by the Tibetan Government-in-Exile during the 1990s, that were used to educate Tibetan exiles living in India about health issues. The purpose is to show how the images promote pronatalism and ethnic endogamy–objectives that Tibetan exiles view as essential steps toward stemming a perceived threat, perpetrated by China, to their existence as a distinct ethnic group. The authors argue that the storybook aesthetics used in these images efface the ideological controversy of their encoded messages by evoking the style and authority of remedial health education.
Sodium requirement of the turkey hen

Abstract 1. Two experiments were conducted to determine the sodium requirement of the Large White turkey hen. 2. A supplementation rate of 0.59 g sodium/kg diet (1.0 g sodium/kg in total) was required for maximum production when the hens were fed a maize‐soyabean meal diet. 3. The egg production of hens receiving a diet without added sodium had fallen to zero after 70 d. After 1.18 g sodium/kg was added to the diet 40% of hens returned to production within 14 d.
Insights on Emerging Trends and the Future of Human Resource Development

The problem and the solution. The future holds countless challenges. The future cannot be known, and it must not be ignored. Understanding trends and indicators emerging today helps us to proactively think about potential future developments and positions us to constructively shape them. This article reports on a survey of 55 human resource development (HRD) and HRD-related practitioners and academics who identified trends, variables, and challenges that they believe are affecting and will affect the profession during the next 15 to 20 years.
Towards an algebraic quantum chromodynamics

We outline a quantum theory of quarks and gluons based on fields with values taken from a noncommutative Jordan algebra. These fields automatically satisfy a triality rule: Quark-antiquark and three-quark states are color singlets. If the elements of the algebra are position dependent, the theory leads to a minimal gauge-invariant coupling between quarks and gluons. The quantization of such a theory is outlined; we find that only color-singlet clusters of quarks and antiquarks have particle properties. The color-nonsinglet fields do not support a representation of the Lorentz group; in fact, their phases are undefined. We conjecture that this can be remedied by a coupling between space-time and flavor symmetries as suggested by Hawking and Pope. Such a coupling naturally leads to one-third-integer values of the quark charges.
Abrupt Transition to Strong Superrotation in an Axisymmetric Model of the Upper Troposphere

Abrupt transitions to strongly superrotating states have been found in some idealized models of the troposphere. These transitions are thought to be caused by feedbacks between the eddy momentum flux convergence in low latitudes and the strength of the equatorial flow. The behavior of an axisymmetric shallow-water model with an applied tropical torque is studied here to determine if an abrupt transition can be realized without eddy feedbacks. The upper-tropospheric layer is relaxed to a radiative equilibrium thickness, exchanging mass and thus momentum with the nonmoving lower layer. For low values of the applied torque, the circulation is earthlike; however, for larger values, an abrupt transition to a strongly superrotating state can occur. In some cases, the system remains superrotating as the torque is subsequently decreased. A simple analytical model is used to better understand the system. The bifurcation is caused by a feedback between the applied torque and the strength of the Hadley cell. As the torque increases, the strength of the cell decreases, reducing the damping caused by momentum transfer from the lower layer.
Search for exotic states with JETSET at LEAR

Several experiments at LEAR concern themselves with meson spectroscopy and searches for exotics in the annihilation of antiprotons with protons at rest. In JETSET we will exclusively study in‐flight annihilations in a search for gluonic states and exotics in the mass region from 1.96 to 2.43 GeV. The experiment uses a molecular hydrogen gas jet target and an advanced general purpose dector, which surrounds the interaction point. One of the unique features of the detector is its excellent kaon identification at the trigger level. This will enable us to achieve our first physics goal of searching resonances in the excitation function of the OZI‐forbidden, ‘‘gluon rich’’ reaction pp→φφ. The physics interest in the φφ channel and additional goals of the collaboration will be outlined.
Potential Mechanisms of Retronasal Odor Referral to the Mouth

The current study took a first step toward elucidating the sensory input that drives retronasal odor referral to the mouth. In 2 experiments, subjects performed odor localization tasks under various oral–nasal stimulation conditions that allowed us to assess the effects of direction of airflow, taste, and tactile stimulation on retronasal odor referral. Subjects reported the locations of perceived odors when food odorants were inhaled through the mouth alone or in the presence of water or various tastants in the mouth. The results indicated that when perceived alone, vanilla and soy sauce odor were localized 54.7%: 26.4%: 18.9% and 60.0%: 21.7%: 18.3% in the nose, oral cavity, and on the tongue, respectively. The localization of odors alone was not significantly different from when water was presented simultaneously in the mouth, indicating that tactile stimulation itself is not sufficient to enhance odor referral. However, the presence of sucrose, but not other tastes, significantly increased localization of vanilla to the tongue. Likewise, only NaCl significantly augmented referral of soy sauce odor to the tongue. These data indicate that referral of retronasal odors to the mouth can occur in the absence of a either taste or touch but that referral to the tongue depends strongly on the presence of a congruent taste.
Wideband IF-Integrated Terahertz HEB Mixers: Modeling and Characterization

This paper presents a detailed study of the IF properties of phonon-cooled NbN hot electron bolometer (HEB) terahertz mixers and receivers, performed over the widest intermediate frequency range reported so far. First, a broadband technique is used to obtain the IF small-signal output impedance of HEB mixers using network analyzer measurements. The impedance is measured over an IF range of 300 kHz to 8.5 GHz under the presence of dc bias and local oscillator (LO) illumination. The LO frequencies (f LO) used in this investigation range from 694 GHz to nearly 2 THz, covering frequencies below and above the superconducting bandgap frequency of the NbN film for the first time. The impedance (real and imaginary parts) can be fitted to the Standard model for HEB devices over almost the entire range of frequencies measured. The impedance data are then used in conjunction with a computer-aided design model for the monolithic micorwave integrated circuit IF amplifier to design and analyze the performance of integrated receivers (mixer/IF amplifier combinations). The measured and predicted variations of the receiver noise, mixer gain, and mixer output noise with IF are in good agreement. A record IF noise bandwidth of 8 GHz (obtained for f LO= 694 GHz) is demonstrated for a receiver designed using the technique described in this paper.
To Invest or Detach? Coping Strategies and Workplace Culture in Service Work

Drawing on original ethnographic research and interweaving food servers' voices with theories of labor, this article examines the emotional content of interactions between customers and workers in restaurants. It addresses the potential benefits of emotional labor, the effect of gender on how workers make sense of and cope with the demands of their jobs, and the work culture that arises as a result of workers' approaches to the emotional demands of their jobs. The article culminates with a discussion of the potential for exploitation when servers, particularly waitresses, begin to care for the customers who pay them.
Analysis and design of a new voltage sag compensator for critical loads in electrical power distribution systems

In this paper, a new voltage sag compensator for powering critical loads in electric distribution systems is discussed. The proposed scheme employs a pulsewidth-modulation AC-AC converter (four insulated gate bipolar transistors per phase) along with an autotransformer. During a disturbance such as voltage sag, the proposed scheme supplies the missing voltage and helps in maintaining rated voltage at the terminals of the critical load. The approach does not employ any energy storage components such as bulk capacitors/inductors and provides fast response at low cost. Under normal conditions the approach works in bypass mode, delivering utility power directly to the load; this method of control allows the transformer to be rated only for transient conditions, thus reducing its required size. A four-step switching technique to drive the AC-AC converter is employed to realize snubberless operation. A design example is presented, and simulation results are shown for a three-phase 230-V 5-kVA system. Experimental results on a single-phase unit are discussed. The proposed approach can be easily integrated into a distribution transformer supplying critical loads.
The effect of pressor and depressor drugs on intramedullary bone-marrow pressure.

1. Intramedullary bone-marrow pressure levels are dependent upon the systemic-blood pressure and the patency of the nutrient artery and possibly other smaller vessels. 2. Intramedullary pressure may be lowered by simultaneously lowering systemic-blood pressure by injection of histamine. The marrow pressure can be increased simultaneously with the systemic pressure by amphetamine. 3. Intramedullary pressure may be lowered while there is a simultaneous rise in the systemic-blood pressure. Adrenalin, nor-epinephrine, and pituitrin produce the response. 4. From the evidence presented, it is believed that the major effect of adrenalin, nor-epinephrine, and pituitrin is produced locally and is independent of systemic-blood pressure. The marked fall in marrow pressure following injection of adrenalin and nor-epinephrine is probably due to vasoconstriction of the nutrient vessels.
A bayesian approach to distinguishing interdigitated muscles in the tongue from limited diffusion weighted imaging

Fiber tracking in crossing regions is a well known issue in diffusion tensor imaging (DTI). Multi-tensor models have been proposed to cope with the issue. However, in cases where only a limited number of gradient directions can be acquired, for example in the tongue, the multi-tensor models fail to resolve the crossing correctly due to insufficient information. In this work, we address this challenge by using a fixed tensor basis and incorporating prior directional knowledge. Within a maximum a posteriori (MAP) framework, sparsity of the basis and prior directional knowledge are incorporated in the prior distribution, and data fidelity is encoded in the likelihood term. An objective function can then be obtained and solved using a noise-aware weighted l1-norm minimization. Experiments on a digital phantom and in vivo tongue diffusion data demonstrate that the proposed method is able to resolve crossing fibers with limited gradient directions.
Toward personalized medicine for the tiniest patients

Maintaining adequate oxygen delivery to the brain is one of the central tasks of the cardiovascular system. A mismatch between cerebral oxygen demand and cerebral perfusion can lead to impaired neurocognitive function, irreversible neurologic damage, and ultimately neuronal cell death. To guard against possible fluctuations in cerebral blood flow, the vasculature of the brain can actively modulate its resistance and thereby regulate its own blood supply—a property termed cerebrovascular autoregulation. This process may be critically underdeveloped in babies born prematurely. With impaired autoregulation, arterial hypotension leads to uncompensated cerebral hypoperfusion, resulting in hypoxic-ischemic injury to the brain. Arterial hypertension, on the other hand, may lead to distention and rupture of fragile cerebral blood vessels, resulting in a hemorrhagic injury. The key, therefore, is to keep arterial blood pressure “normal” in premature babies. But what is the normal blood pressure for a 750 g newborn that was delivered 14 weeks too early and whose mean arterial pressure (MAP) measures a mere 29 mm Hg? A rational approach to personalized hemodynamic management in this vulnerable population is currently lacking. To close this gap, da Costa and colleagues evaluated a new index of cerebrovascular autoregulation. This index was the correlation coefficient between slow-wave fluctuations in tissue oxygenation (measured by near-infrared spectroscopy) and heart rate. A low absolute value of the correlation coefficient indicated intact cerebrovascular autoregulation. The authors defined an optimal blood pressure for an individual baby as the MAP value of the baby corresponding to the lowest associated value of the new autoregulation index, thus maximizing the brain’s autoregulatory capacity. In a cohort of 60 preterm babies, the authors were able to demonstrate that babies with measured MAPs significantly below the calculated individualized optimal blood pressure had an increased rate of mortality, whereas those with MAPs exceeding the optimal blood pressure suffered from more severe cerebral hemorrhage. Their results suggest that personalization of hemodynamic management may be possible by titrating blood pressure so as to maximize a baby’s autoregulatory capacity. Given the potential for severe and lifelong disability stemming from brain injury early in life, these results are encouraging and call for prospective validation to improve the care of the tiniest and most fragile of patients. C. S. da Costa et al ., Monitoring of cerebrovascular reactivity for determination of optimal blood pressure in preterm infants. J. Pediatr. 10.1016/j.jpeds.2015.03.041 (2015). [[Abstract]][1] [1]: http://www.jpeds.com/article/S0022-3476%2815%2900342-X/abstract