cssi/SciSciGPT-SciSciNet huggingface dataset:
Generalized Fourier Nuclear Magnetic Resonance (NMR) Imaging Methods

The speed and accuracy with which NMR imaging methods can produce images in the presence of an inherently low signal-to-noise ratio is a major issue in the development of NMR imaging as a clinical imaging modality. In this regard, the Fourier and zeugmatographic techniques are among the most efficient in that they gather and interpret NMR signals from all portions of the imaged region simultaneously. Fourier NMR imaging has usually been viewed as a process of obtaining NMR spectra in the presence of constant field gradients followed by interpretation of the spectral distributions as projected spatial distributions. An equally valid perspective interprets the noisy raw NMR signals (FIDs) as corrupted partial spatial-frequency mappings of the imaged object. Insights afforded by this viewpoint are translatable straightforwardly into theoretical formulations which permit 1) quantitative comparison of performance characteristics of existing Fourier methods (including the zeugmatographic methods), and 2) derivation of new methods with optimal spatial-frequency sensitivity and accuracy characteristics, or with reduced minimum imaging times. A brief mathematical development of this spatial-frequency-domain interpretation of Fourier NMR imaging is followed by derivation of a proposed NMR imaging method with imaging performance capabilities superior to those of existing Fourier NMR imaging methods. Simulation results supporting these theoretical results are presented. Use of other optimality criteria to derive other new imaging methods is discussed.© (1982) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The Gandras catheter for uterine artery embolization: the procedure-driven development of a novel medical device.

Uterine artery embolization (UAE) is a safe and effective therapy for women suffering from symptomatic fibroid tumors of the uterus. In order to complete the procedure, the interventionalist must be able to catheterize both uterine arteries from a single femoral puncture site. The uterine arteries are subsequently embolized, or occluded, to stasis by injecting small particles mixed with radio opaque contrast under fluoroscopic guidance. Historically, it has been necessary to use several different catheters of varying shapes, lengths and materials to accomplish the catheterization of both uterine arteries when performing UAE. Every catheter exchange increases the length and difficulty of the procedure. The risk and radiation dose of any interventional radiological procedure is directly proportional to its overall duration. Thus if a single catheter could achieve the objective of catheterizing the bilateral uterine arteries for UAE throughout the procedure, its use would decrease the length of the procedure...
Theory of the quantized hall conductivity plateaus of two-dimensional electron systems

Abstract The width of the plateaus of the quantized Hall conductivity of two- dimensional electron systems is expected to drop sharply as a function of μBH/kT from the zero point value of 2mμ B H/π h ; 2 , when it is expressed in terms of electron density.
Resource use in the tropical karstlands of central Belize

Rural tropical ecosystems are subject to many traditional land uses that employ the indigenous karst resources: rock, water, soil, vegetation, and wildlife. Individual resource pressures often are subtle, but their combined impact can precipitate instability in the tropical karst environment, potentially resulting in disruption of food, water, and fuel supplies. The karst of central Belize was used intensively for some six centuries by Maya farmers, but between the 10th and 19th centuries AD most of it reverted to secondary forest. Commercial logging dominated the 19th and early 20th centuries, followed by the expansion of subsistence and commercial agriculture after 1945. In the 1980s resource use has accelerated as population and other pressures increase. Much karst remains forested, but there is increasing clearance for agricultural uses, particularly for citrus cultivation and small-scale mixed agriculture. Soil depletion has begun to occur, water resources are increasingly taxed, and some wildlife is threatened by habitat destruction and increased hunting. Lime production for the citrus industry has promoted quarrying, water extraction, and fuelwood use. Environmental stresses currently do not exceed the threshold of instability, but the rapidly developing rural economy warrants careful monitoring of resource pressures.
MicroRNAs Regulate and Provide Robustness to the Myogenic Transcriptional Network

The genetics of skeletal muscle lineage commitment are deceptively complicated. MyoD overexpression is sufficient to convert fibroblasts into skeletal muscle myotubes. In vivo, there are a number of different steps of differentiation that require a large network of transcription factors that control differentiation and homeostasis of skeletal muscle progenitors. Each transcription factor has been shown to have the ability to promote the next factor in the cascade, but the mechanisms regulating the transitions remain incomplete. Recently, microRNAs have been shown to be important for a large number of developmental and oncogenic processes. In this review, we will discuss recent advances in the understanding of how microRNA is critical for skeletal muscle development by interacting with protein-coding genes that had previously been shown to be important for myogenesis.
Stalled democratization of an authoritarian regime: The case of Algeria

Algeria has experienced important transformations since the bloody riots of October 1988. Numerous political reforms have been initiated, due to the pressure exerted by an emerging civil society; also the regime has been subject to fragmentation, thus exacerbating the power struggle among various political clans. The now‐banned Islamic Salvation Front (FIS), emerging as the most powerful party, eclipsed the old ruling party, the National Liberation Front (FLN). Algerian society today is completely polarized while the intensification of violence since the interruption of the political process, in January 1992, has prolonged the political stalemate. This article deals with the reasons why the authoritarian rulers initiated a process of democratization in the first place: the principal political reforms; the contending parties in the political arena; the reasons for the initial popularity of the FIS and the tactics used by factions of the FLN‐State to prolong the life of the old regime. Also the role of the ...
Agonistic and sexual behaviour in the Chukar Partridge (Alectoris graeca)

Abstract Agonistic and sexual behaviour in Chukar Partridges was observed by placing together two birds at a time in an indoor pen for 15-minute trials. Each of 9 males and 5 females was matched against all other birds, and their various elements of behaviour recorded by 1-minute intervals. Males were highly intolerant of each other with a clear-cut, straight-line dominance relationship among the 9 birds. Outcome of encounters was usually settled within the first few minutes of a trial. Behaviour of dominant males was distinct from that of subordinate ones. Females were highly tolerant of each other but when intolerant showed the same behaviour as males although at lower frequency and intensity. Male and female birds tended to tolerate each other during the first minute of an encounter when copulation was likely to occur. With the presumed sudden drop in sexual tendency, the male then became highly aggressive towards the female as evidenced by waltzing, attack, and rape. The female avoided and was often entirely submissive. As the male's aggressiveness waned, tidbitting replaced waltzing. Tidbitting results from a thwarted sex tendency. It appeased the female who approached the male with copulation then resulting. Aggressiveness, as indicated by waltzing, had a strong influence upon the time and frequency of occurrence of much male and female behaviour. Much of what appears to be courtship is in reality aggression by the male. True sexual activity occurs as tidbitting and is relatively inconspicuous and infrequent. The function of waltzing was to establish the male's dominance over the female and as a means of sex identification. Tidbitting appeased the female and induced her to crouch for copulation. The nest ceremony functions to strengthen the pair bond in a species where the male plays an important parental role.
Silicon and indium doping of GaAs: Measurements of the effect of doping on mechanical behavior and relation with dislocation formation

Abstract The effect of indium and silicon doping on dislocation formation in GaAs single crystals has been studied experimentally using dynamic compression tests and indentation rosettes. By direct measurements of the critical resolved shear stress (CRSS) in temperature range from 400 to 1100° C using dynamic compression tests, we found that at the melting point, the critical resolved shear stress of GaAs: In is twice that of undoped GaAs. More recent measurements show that at high temperatures (T ⩾ 1000° C) the critical resolved shear stress of silicon-doped crystals is lower than that of undoped GaAs. Well-defined indentation rosettes were obtained at high temperatures from a Vickers indenter using small loads. Analysis of such rosettes confirm that the mechanical behavior of the GaAs crystals is not drastically affected by the presence of dopants. Reduction of dislocation densities in doped crystals is attributed to modifications introduced by the dopant in the equilibrium concentration of native defects at the melting point (particularly gallium and arsenic vacancies).
“The Negro at the Gate”: Enslaved Labor in Eighteenth-Century Boston

In eighteenth-century Boston, slaves participated in a diversified economy that allowed some of its members to challenge and manipulate the institution of slavery from within, thus bringing themselves a measure of autonomy and the opportunity to enjoy the fruits of their labor.
Employing web mining and data fusion to improve weak ad hoc retrieval

When a user issues a reasonable query to a retrieval system and obtains no relevant documents, he or she is bound to feel frustrated. We call these weak queries and retrievals. Improving their effectiveness is an important issue for ad hoc retrieval and would be most rewarding for these users. We explain why data fusion of sufficiently dissimilar retrieval lists can improve weak query results and confirm this with experiments using short and medium size queries. To realize sufficiently dissimilar retrieval lists, we propose composing alternate queries through web search and mining, employ them for target retrieval, and combine with the original query retrieval list. Methods of forming web probes from longer queries, including salient term selection and query text window rotation, are investigated. When compared with normal ad hoc retrieval, web assistance and data fusion can more than double the original weak query effectiveness. Other queries can also improve along with weak ones.
Heat transfer in the thermal entrance of non-Newtonian fluid flow

The problem of heat transfer for fully developed flow of a third order Rivlin-Ericksen type of non-Newtonian fluid in a channel has been studied by means of the variational formulation. Consideration is given to the case when the walls of the channel are kept at one constant temperature upstream of the origin and at a different constant temperature downstream. A solution is presented for the temperature distribution and Nusselt number variation with dimensionless axial distance.
Minimum fuel powered dynamic soaring of unmanned aerial vehicles utilizing wind gradients

This paper studies optimal powered dynamic soaring flights of unmanned aerial vehicles (UAVs) that utilize low-altitude wind gradients for reducing fuel consumptions. Three-dimensional point-mass UAV equations of motion are used, and linear wind gradients are assumed. Fundamental UAV performance parameters are identified through the normalization of the equations of motion. In particular, a single wind condition parameter is defined that represents the combined effect of air density, UAV wing loading, and wind gradient slope on UAV flight. An optimal control problem is first used to determine bounds on wind conditions over which optimal powered dynamic soaring is meaningful. Then, powered UAV dynamic soaring flights through wind gradients are formulated as non-linear optimal control problems. For a jet-engined UAV, performance indices are selected to minimize the average thrust required per cycle of powered dynamic soaring that employs either variable or constant thrust. For a propeller-driven UAV, in comparison, performance indices are selected to minimize the average power required per cycle of powered dynamic soaring with either variable or constant power. All problem formulations are subject to UAV equations of motion, UAV operational constraints, proper initial conditions, and terminal conditions that enforce a periodic flight. These optimal control problems are converted into parameter optimization with a collocation method and solved numerically using the parameter optimization software NPSOL. Analytical gradient expressions are derived for the numerical solution process. Extensive numerical solutions are obtained for a wide range of wind conditions and UAV performance parameters. Results reveal basic features of powered dynamic soaring flights through linear wind gradients. Copyright © 2004 John Wiley & Sons, Ltd.
Energy Metabolism of Broiler Breeder Hens.1. The Partition of Dietary Energy Intake

The partitioning of AME intake (MEI) and recovered energy (RE; defined as MEI minus heat production) was investigated on Hubbard broiler-breeder hens (BB) by using indirect calorimetry and energy balance. The regression of RE on MEI was linear (R2 = .96; P less than .01) with a slope of .817 +/- .024 (SE) and a y-intercept of -238.3 +/- 10.7 (SE). The maintenance energy requirement was 292 kilojoule (kJ) per kg per day (367 kJ per kg.75 per day). The regression of body RE, defined as RE minus egg energy, on MEI was linear (R2 = .96; P less than .01) with a slope of .799 +/- .045 (SE) and a y-intercept of -344.9 +/- 19.7 (SE). Therefore, an MEI of 432 kJ per kg per day was required by BB hens to maintain body energy equilibrium when they were laying at approximately 85% production. At an MEI of less than 432 kJ per kg per day, body energy was used for egg production. The AME cost of depositing 1 kJ of body, egg, protein, or fat energy was (mean +/- SE) 1.21 +/- .06, 91 +/- .32, 1.96 +/- .71, and 1.05 +/- .15 kJ, respectively. The results indicate that individually caged BB hens between 28 and 36 wk of age in a thermal-neutral environment (21 C) require approximately 1.6 megajoule (MJ) of AME per bird per day for normal growth (3 g/per day) and egg production (85%).
Structure of three class I human alcohol dehydrogenases complexed with isoenzyme specific formamide inhibitors

Formamides are aldehyde analogues that have demonstrated potent and selective inhibition of human alcohol dehydrogenase isoenzymes. The alphaalpha, beta(1)beta(1), gamma(2)gamma(2), and sigmasigma isoforms have all been found to be strongly inhibited by substituted formamides. In this paper, the structure of the alphaalpha isoform of human alcohol dehydrogenase complexed with N-cyclopentyl-N-cyclobutylformamide was determined by X-ray crystallography to 2.5 A resolution, the beta(1)beta(1) isoform of human alcohol dehydrogenase complexed with N-benzylformamide and with N-heptylformamide was determined to 1.6 and 1.65 A resolution, respectively, and the structure of the gamma(2)gamma(2) isoform complexed with N-1-methylheptylformamide was determined to 1.45 A resolution. These structures provide the first substrate-level view of the local structural differences that give rise to the individual substrate preferences shown by these highly related isoenzymes. Consistent with previous work, the carbonyl oxygen of the inhibitors interacts directly with the catalytic zinc and the hydroxyl group of Thr48 (Ser48 for gamma(2)gamma(2)) of the enzyme. The benzene ring of N-benzylformamide and the carbon chains of N-heptylformamide and N-1-methylheptylformamide interact with the sides of the hydrophobic substrate pocket whose size and shape is dictated by residue exchanges between the beta(1)beta(1) and gamma(2)gamma(2) isoenzymes. In particular, the exchange of Ser for Thr at position 48 and the exchange of Val for Leu at position 141 in the gamma(2)gamma(2) isoenzyme create an environment with stereoselectivity for the R-enantiomer of the branched N-1-methylheptylformamide inhibitor in this isoenzyme. The primary feature of the alphaalpha isoform is the Ala for Phe93 exchange that enlarges the active site near the catalytic zinc and creates the specificity for the branched N-cyclopentyl-N-cyclobutylformamide inhibitor, which shows the greatest selectivity for this unique isoenzyme of any of the formamide inhibitors.
Particle productivity in pp and pA collisions.

In the framework of the geometrical branching model for pp and pA collisions, we discuss the dependence of the particle-productivity function on impact parameter and give a new description for it without any free parameter. It is then shown that an excellent description of the pp data is obtained.
Adult attachment and dating strategies: How do insecure people attract mates?

When asked to choose among secure or insecurely attached partner prototypes, research shows that people tend to select secure individuals as their first choice. Despite this pattern, not everyone chooses secure partners in reality. The goal of this study was to examine the ways in which insecure individuals present themselves that might make them attractive to others. To achieve this goal, participants were led to believe that they were interacting with a possible date. That insecure individuals presented themselves as warm, engaging, and humorous people when communicating with potential mates were found. These findings suggest that insecure people have numerous dating tactics and positive qualities that they display to win over romantic partners.
Volume flux during folding in the Helvetic nappes, Switzerland

Volume loss due to pressure solution along spaced cleavage and volume gain represented by dilatant veins have been quantified for folded carbonates from the Helvetic nappes. Samples from two formations with low clay contents (
Frax prediction without BMD for assessment of osteoporotic fracture risk.

ABSTRACT Objective To compare Fracture Risk Assessment Tool (FRAX) calculations with and without bone mineral density (BMD) in predicting the 10-year probability of hip and major osteoporotic fractures (MOF). Methods A cross-sectional review of patients requiring screening for osteoporosis as part of their routine medical care was conducted. Postmenopausal women and men over 50 years of age who were never diagnosed with osteoporosis or treated with U.S. Food and Drug Administration-approved agents for osteoporosis were included. Height, weight, FRAX questionnaire, femoral neck BMD, and T-score data were obtained. FRAX scores with BMD (FRAX/BMD) and without BMD (FRAX) were calculated. Subjects were separated on the basis of identical and different treatment recommendations. Fracture risk factors were compared between groups using simple Student’s t test analysis of numerical variables and Fisher’s exact test analysis of binary variables. Results Of 151 total subjects, 127 (84%) had identical fracture risk predictions with or without BMD included in the FRAX calculation. Thirty subjects met treatment criteria and 97 did not, but the FRAX prediction was the same with risk factors alone or with risk factors plus BMD. Age was the only risk factor that was significantly different between those with identical and different predictions (median age, 64.42 and 76.25 years, respectively; P<.001). Conclusion In most cases, FRAX alone provides the same prediction as FRAX with BMD. Younger age is more indicative of an identical prediction. (Endocr Pract. 2013;19:780-784)
Connections in acyclic hypergraphs: extended abstract

We demonstrate a sense in which the equivalence between blocks (subgraphs without articulation points) and biconnected components (subgraphs in which there are two edge-disjoint paths between any pair of nodes) that holds in ordinary graph theory can be generalized to hypergraphs. The result has an interpretation for relational databases that the universal relations described by acyclic join dependencies are exactly those for which the connections among attributes are defined uniquely. We also exhibit a relationship between the process of Graham reduction [6] of hypergraphs and the process of tableau reduction [1] that holds only for acyclic hypergraphs.
The expression of antiapoptotic protein survivin is transcriptionally upregulated by DEC1 primarily through multiple sp1 binding sites in the proximal promoter

Human differentially expressed in chondrocytes (DEC), mouse stimulated with retinoic acid and rat split and hairy related proteins constitute a structurally distinct class of the basic helix-loop-helix proteins. DEC1 is abundantly expressed in tumors and protects against apoptosis induced by serum starvation. In this study, we report that DEC1 antiapoptosis is achieved by inducing survivin, an antiapoptotic protein. In paired tumor–normal tissues, survivin and DEC1 exhibited a paralleled expression pattern. Tetracycline-induced expression of DEC1 in stable lines proportionally increased the expression of survivin. In reporter assays, DEC1 transactivated the survivin promoter but repressed the DEC2 promoter. In contrast to the repression, the activation was delayed and varied depending on serum concentrations and cycle blockers. Studies with reporter mutants located, in the survivin promoter, two Sp1 sites that supported DEC1 transactivation. Electrophoretic mobility shift assay and chromatin immunoprecipitation detected the presence of DEC1 in the survivin promoter. These findings establish that the survivin gene is a transcription target of DEC1, and induction of survivin is at least in part responsible for DEC1 antiapoptosis.
Peierls transition in a quasi-one dimensional system☆

Abstract We study the thermodynamics of a noninteracting electron system with a half filled strongly anisotropic tight binding band in the mean field approximation. This system may exhibit a structural transition dimerizing along the high conductivity direction. The conditions for the instability to occur are given as a function of the degree of anisotropy. The relationship to the behavior of TCNQ salts is discussed.
Spectral broadening of VLF transmitter signals observed on DE 1: A quasi-electrostatic phenomenon?

Spectrally broadened VLF transmitter signals are observed on the DE 1 satellite using alternatively both electric and magnetic field sensors. It is found that at times when the electric field component undergoes significant bandwidth expansion (up to about 110 Hz) the magnetic field component has a bandwidth of less than 10 Hz. The results support the theory that the off-carrier components are quasi-electrostatic in nature. Measurement of the absolute E and B field magnitudes of the broadened signals are used to determine the wave Poynting vector. It is found that the observed power levels can be understood without invoking any strong amplification process that operates in conjunction with the spectral broadening. The implications of this finding in distinguishing among the various possible mechanisms for spectral broadening are discussed.
The effect of chronic maternal alcohol consumption on the development of central nervous system myelin subfractions in rat offspring

Abstract Female Sprague-Dawley rats were pair-fed using isocaloric control or 6.6% (v/v) ethanol liquid diets for one month prior to conception and throughout gestation. The development of three central nervous system (CNS) myelin subfractions was examined in the 18- to 54-day-old offspring (control and ethanol pups) of control and ethanol-treated females. During the same age period, the in vivo incorporation of [ 3 H] leucine into myelin subfraction proteins and of [ 14 C] glucose into myelin subfraction lipids was also studied. Despite the fact that the ethanol pups consistently had smaller brain and body weights than normal rats, 18- and 25-day-old ethanol pups had more CNS myelin than control pups. However, the increased myelin content was due solely to an excess of the chemically and morphologically immature heavy myelin fraction. Fifty-four-day-old ethanol pups had a small deficit of total CNS myelin. Developing ethanol pups also demonstrated abnormal rates of incorporation of [ 3 H] leucine and [ 14 C] glucose into the myelin subfractions. At 18 and 25 days, the ethanol pups incorporated more of both precursors into all fractions of myelin, while at 54 days they demonstrated decreased incorporation. Although the quantity and rate of synthesis of individual myelin subfractions was abnormal in ethanol pups, the protein composition of the separated subfractions was normal. In addition, the ethanol pups had a normal distribution of 3 H and 14 C radioactivity, in separated myelin subfraction proteins and lipids, respectively. The results of the present study suggest that the consumption of a 6.6% (v/v) ethanol liquid diet prior to conception and throughout gestation resulted in a premature onset and slow-down of active myelination.
The energetics of the lower stratosphere including radiative effects

Approximate solutions of radiative heating are developed using monthly mean radiative parameters and are combined with the geopotential and temperature fields to study the energetics of the Northern Hemisphere lower stratosphere on a daily basis for 1964. Significant leakage of energy from the troposphere occurs throughout the year and absorption of this energy in the lower stratosphere contributes to the maintenance of the eddies for all months except January. In winter there is significant transmission of tropospheric energy into the upper stratosphere which suggests a close coupling of the upper and lower atmospheres. The seasonal circulations are examined and it is found that the spring warming of 1964 was due to a period of enhanced convergence of tropospheric energy flux. In the fall absorption of tropospheric energy intensifies the flow. The role of radiation is to destroy available potential energy for all months of the year.
Effects of magnetostatic interaction on domain microstructure evolution in magnetic shape memory alloys: Phase field simulation

Domain microstructure evolution during magnetic field-induced twin boundary motion in magnetic shape memory alloys was investigated using phase field micromagnetic microelastic modeling. The computer simulations show bending and splitting of magnetic domain walls, magnetization rotation due to external and internal magnetic fields and pinning of magnetic domain wall motion at twin boundaries. The study reveals the important roles of magnetostatic interaction in the domain processes, providing insights into the complex domain phenomena in magnetic shape memory alloys and explaining experimentally observed domain microstructures.
Chain Packing Analysis of the Passivating Layer on Nanocrystalline Quantum Dot Surfaces

The organic passivant layer on nanomaterial surfaces has been examined by correlating the phase behavior of the passivant using attenuated total reflection infrared spectroscopy (ATR-IR), coupled with differential scanning calorimetry (DSC). The thermodynamic melting dynamics in the passivant layer supports the description of self-assembled monolayer-like interactions, with an initial constrained chain melting followed by modulation of the surface packing. Correlation of chain length with particle diameter and headgroup functionality suggests that in systems in which the radius of the particle is larger than the passivant layer thickness, chain-chain interactions dominate thermodynamic stabilities, with only a minimal contribution from headgroup stabilization of the passivating layer.
Crystallographic texturing in Nb3Sn multifilamentary superconducting composites

Crystallographic texturing in Nb3Sn composites, fabricated by both the external diffusion and the commercial bronze processes, has been investigated. In the external‐diffusion‐processed composite the as‐drawn texture of the copper matrix contained ca. 55% 〈111〉 and 45% 〈100〉; after recrystallization at 650 °C for 16 h this changed to 70% 〈111〉 and 30% 〈100〉. Tin plating and reaction heat treatment for 40 h at 650 °C eliminated most of the texturing. In a commercial bronze‐processed composite a 〈211〉 or 〈221〉 texture was obtained in the as‐drawn bronze matrix, and after a reaction heat treatment at 700 °C for 30 h a diffuse 〈100〉 texture was developed. In both composites the Nb3Sn reaction layer exhibited no preferred orientation.
Unwanted Intrusive Thoughts and Cognitive Functioning in Kindergarten and Young Elementary School-Age Children Following Hurricane Katrina

Seven months after Hurricane Katrina, 183 five- to eight-year-old children were surveyed about their own intrusive thoughts and tested on their level of cognitive functioning (knowledge about the mind and the mind's operations). Basic developmental research suggests that children who lack sufficient knowledge about the mind should have difficulties answering questions about intrusive thoughts. Hurricane-affected children reported relatively more intrusive thoughts with negative content than nonaffected children reported. An association between children's level of understanding of the mind and their ability to report on their own intrusive thoughts supports this hypothesis. Results point to a funneling of intrusive thoughts toward negative content following a traumatic event and highlight the importance of considering children's level of understanding of the mind when investigating intrusive thoughts in young children.
Paracellular transport characteristics of Aplysia juliana intestine

Abstract 1. 1. Current-voltage measurements strongly suggested the existence of a low resistance paracellular pathway in the intestinal epithelium. 2. 2. Na + and Cl − transport across the intestine involved both a cellular and a paracellular pathway. 3. 3. The paracellular pathway for both Na + and Cl − constituted the major conductive route for these ions. 4. 4. Diffusion potentials in the intestinal epithelium were symmetrical.
VIBRIO PARAHÆMOLYTICUS OUTBREAKS IN THE UNITED STATES

Abstract Vibrio parahœmolyticus has only lately been recognised as a significant cause of gastroenteritis outbreaks in the United States. By 1972, thirteen outbreaks have been reported, and the epidemiological, clinical, bacteriological, and environmental aspects of these outbreaks are reviewed here. Outbreaks were reported from eight States, ranging from the Atlantic seaboard to the Gulf of Mexico, Pacific northwest, and Hawaii. Crab, shrimp, lobster, and oysters were involved as vehicles. Cooked seafood was responsible for all but two of the outbreaks. A variety of different serotypes of the organisms were involved. Errors in refrigeration, cooking, or food-handling hygiene contributed to the incidents.
Dietary magnesium prevents fructose-induced insulin insensitivity in rats.

Increased dietary fructose may produce insulin insensitivity and elevate blood pressure in rats. It is possible that the reduced magnesium content of the high-fructose commercial diet used in some studies may play a role in these abnormalities because it is known that magnesium deficiency can produce insulin insensitivity and increased angiotensin II action in humans. To study this, we maintained rats for 9 weeks on either a normal control diet, a standard high-fructose diet, or the same high-fructose diet supplemented with magnesium. Glucose uptake was assessed using a perfused rat hindquarter preparation sequentially with 0, 900, and 120,000 pmol/L of added insulin. Basal serum glucose, plasma insulin, and basal glucose uptake in the absence of insulin were similar among all three groups. However, insulin sensitivity, defined as glucose uptake in the presence of 900 pmol/L insulin minus basal, was depressed in the high-fructose compared with the control group (1.02 +/- 0.38 to 1.77 +/- 0.57 mumol/g per hour, P < .05). In contrast, the high-fructose group supplemented with normal magnesium had similar insulin sensitivity as the control group (2.09 +/- 0.69 mumol/g per hour). Total serum magnesium was reduced in the high-fructose group compared with control or high-fructose plus magnesium-supplemented groups. Blood pressure and fasting insulin levels were also lower in the magnesium-supplemented group. These results suggest that magnesium deficiency and not fructose ingestion per se leads to insulin insensitivity in skeletal muscle and changes in blood pressure.
Skyrmions from instantons at finite temperature

Abstract The recent proposal by Atiyah and Manton to construct R 3 skyrmions from R 4 instantons is extended to finite temperature instantons using Polyakov lines. The relevance of the latter for baryons as skyrmions at finite temperature is discussed.
Varicella zoster as a manifestation of immune restoration disease in HIV-infected children.

Abstract Background Exacerbation of opportunistic infections in HIV-infected patients shortly after initiation of highly active antiretroviral therapy (HAART) has been named immune restoration disease (IRD). Thus far, IRD has not been reported in children. Objective We describe the clinical and immune characteristics of IRD in HIV-infected children treated with HAART. Methods A historical cohort study was conducted in a tertiary HIV center in perinatally HIV-infected children who were started on a first stable HAART between January 1996 and July 2002. The incidence of opportunistic infections, newly AIDS-defining events or death after initiation of HAART, and virologic and immunologic information was evaluated at baseline and every 3 months post-HAART. Results Sixty-one perinatally HIV-infected children were started and maintained on HAART for >6 months. Seven episodes of IRD occurred. All were cutaneous herpes zoster (HZ). Children who developed HZ had significantly lower baseline CD4 + and CD8 + T-cell numbers compared with children who did not. HZ occurred only in children (7 of 34 subjects) with virological and immunological success to HAART. In children with a previous history of varicella infection, the risk of developing HZ after HAART was higher in those without a protective level of varicella-specific IgG (50%, or 5 of 10 subjects) compared with those with seroprotection (10%, or 2 of 20). Conclusion Herpes zoster is a common manifestation of IRD in HIV-infected children after the initiation of HAART. Risks for developing HZ include no protective varicella-specific antibody despite previous varicella infection, severe immunodeficiency at baseline, and vigorous immunologic and virologic responses to HAART.
A discrete-time direct-torque and flux control for direct-drive PMSG wind turbines

This paper proposes a novel discrete-time direct-torque and flux control (DTFC) scheme for a permanent-magnet synchronous generator (PMSG) used in a variable-speed direct-drive wind power generation system. The proposed DTFC does not rely on machine parameters, such as the inductances and permanent-magnet flux linkage, while the main advantages of the DTC, e.g., fast dynamic response and no need of coordinate transform, are preserved. The stator flux linkage is estimated by an adaptive low-pass filter (LPF), in which a variable cutoff frequency is used. The adaptive LPF stator flux observer can achieve high estimation precision over a wide operating range of the PMSG. A space-vector modulation (SVM) module is integrated into the control scheme of the PMSG to achieve a fixed switching frequency as well as lower flux and torque ripples when comparing with the conventional DTC. The overall control scheme is simple to apply and is robust to parameter uncertainties and variations. The effectiveness of the proposed discrete-time DTFC scheme is verified by simulation and experimental results on a 2.4-kW PMSG used in a variable-speed direct-drive wind turbine system.
Titan's Snowline

Abstract We show that the “snowline” altitude on Titan, above which the condensed nonideal methane–nitrogen phase is solid, is lower (∼14 km) near the equator than at high latitudes (∼19 km). This counterintuitive result derives from the thermodynamic behavior of the binary condensate. The snowline altitude is an operating constraint on future Titan missions where icing would pose a ceiling on atmospheric flight. These snowline altitudes are higher than likely topography, suggesting that optically bright regions on Titan are not due to veneering caused by methane frost deposition.
Secondary amenorrhea and infertility caused by an inhibin-B-producing ovarian fibrothecoma.

Abstract Objective: To report a case of secondary amenorrhea and infertility caused by an inhibin-B-producing ovarian fibrothecoma. Design: Case report. Setting: Academic medical center. Patient: A 37-year-old woman with a 2-year history of secondary amenorrhea and infertility. Intervention(s): Operative removal of a 5-cm ovarian fibrothecoma. Main Outcome Measure(s): Luteinizing hormone, FSH, E 2 , inhibin-B, TSH, and prolactin measured preoperatively and postoperatively. Immunostaining of tumor cells for inhibin and LH. Result(s): Preoperative hormone levels were as follows: FSH, 1.7 mIU/mL; LH, 23.4 mIU/mL; E 2 , 31 pg/mL; and inhibin B, 1,154 pg/mL. Three weeks postoperatively, the FSH was 1.5 mIU/mL, LH decreased to 7.1 mIU/mL, E 2 increased to 276 pg/mL, and inhibin-B decreased to 17 pg/mL. The fibrothecoma did not stain for LH but was strongly positive for inhibin. Regular menstrual cycles resumed 28 days postoperatively. Conclusion(s): Inhibin-B produced by an ovarian tumor profoundly suppressed FSH levels and resulted in secondary amenorrhea and infertility. Use of sensitive and specific immunoassays for inhibin-A and -B may aid in the differential diagnosis of hormonally active ovarian tumors.
Influence of soil gas contamination on tree root growth

Rooted-cuttings and saplings of green ash (Fraxinus lanceolata) and hybrid poplar (Populus spp) were planted on a former municipal refuse landfill and on a nearby nonlandfill control plot. The root systems of four trees of each species and size were excavated on the landfill plot-two growing in an area where the concentrations of anaerobic landfill gases were relatively high and two in a relatively low-gas area. Two trees of each species and size were also excavated on the control. The root systems of both species were significantly shallower on the landfill plot than on the control. Green ash appeared to avoid the adverse gas environment of the deeper soil layers on the landfill by producing adventitious roots. Hybrid poplar became adapted in a different manner, by redirecting root growth from the deepter soil layers to the soil surface.
Electromechanical Transient Performance of Induction Motors

This paper is the result of a differential analyzer study of the starting characteristics of 2-phase induction motors. The prototype of the motors investigated is the small 2-phase machine commonly used in closed cycle control systems. The performance equations of the induction motor are solved, and summary curves based upon the conclusions reached are presented in a form useful to motor designers. No published data of this type have come to the attention of the authors. It is hoped that the results herein reported can be utilized in the design of better motors for servo applications.
Coming to Grips with a “New” State of Consciousness: The Study of Rapid-Eye-Movement Sleep in the 1960s

The recognition of rapid-eye-movement sleep (REM) and its association with dreaming in 1953 by Aserinsky and Kleitman opened a new world to explore in the brain. Discussions at two major symposia in the early 1960s reveal that a state with characteristics resembling both wakefulness and sleep was overturning accepted views of the regulation of the two states. Participants grappled with the idea that cortical activation could occur during sleep. They struggled with picking a name that would capture the essence of REM without focusing on just one aspect of the state. Questioning whether REM in cats could be homologous with that of humans suggested an anthropocentric focus on human dreaming as the essence of the state. The need for biochemical studies was evident given that deprivation of REM caused a rebound in the amount of subsequent REM, which indicated that simple synaptic activity could not support this phenomenon.
An improved synthesis of α,β-unsaturated nitrones relevant to the stephacidins and analogs thereof

A new method is reported for the synthesis of the α,β-unsaturated nitrone moiety characteristic of the stephacidin/avrainvillamide family of bioactive prenylated indole alkaloids. Application to the synthesis of stephacidin analogs and a potential biological probe are showcased.
Optical transitions in semiconductor superlattices with zinc-blende structure in the k

Transition-matrix elements for superlattices consisting of materials with the zinc-blende structure are presented in analytical form in the k\ensuremath{\cdot}p approximation including the ${\mathrm{\ensuremath{\Gamma}}}_{6}$, ${\mathrm{\ensuremath{\Gamma}}}_{7}$, and ${\mathrm{\ensuremath{\Gamma}}}_{8}$ bands. The resulting selection rules for cases where the magnetic field is absent, and where the magnetic field is applied perpendicular to the superlattice layers, are discussed. The results can be used for type-I, -II, and -III superlattices. They can also be used for other systems, such as a single quantum well.
A Coaxial Wavewide Commutator Feed for a Scanning Circular Phased Array Antenna

A coaxial waveguide amplitude commutation feed system has been developed for application to the scanning circular array antenna problem. A dominant TEM mode and a pair of orthogonal TE/sub 11/ modes suitably excited at the input of a coaxial waveguide feed are employed to generate a simply commutatable low-sidelobe discrete amplitude distribution at the peripheral output ports of the coaxial circular array feed. The major advantages of the coaxial commutator feed compared to other circular array feed types are the broad bandwidth and small insertion loss simultaneously achieved with a simple feed geometry. The design and measured performance capability of a 30-percent RF bandwidth low-sidelobe coaxial commutator feed are described in detail.
EXPLORING THE DRIVERS OF INTERORGANIZATIONAL RELATIONSHIP MAGNITUDE

Firms manage a portfolio of different relationships within their supply chains. Because each relationship is unique, the context from which it develops is unique as well. Utilizing a qualitative study, this research explored the situational drivers that influence the magnitude of the relationship that firms develop. Eight drivers were identified: capabilities, expected benefits, external influence, history, importance, interpersonal interaction, performance, and strategy congruence. Theoretical and managerial implications and research opportunities are provided.
Visual Scanning of Faces in Autism

The visual scanpaths of five high-functioning adult autistic males and five adult male controls were recorded using an infrared corneal reflection technique as they viewed photographs of human faces. Analyses of the scanpath data revealed marked differences in the scanpaths of the two groups. The autistic participants viewed nonfeature areas of the faces significantly more often and core feature areas of the faces (i.e., eyes, nose, and mouth) significantly less often than did control participants. Across both groups of participants, scanpaths generally did not differ as a function of the instructions given to the participants (i.e., “Please look at the faces in any manner you wish.” vs. “Please identify the emotions portrayed in these faces.”). Autistic participants showed a deficit in emotion recognition, but this effect was driven primarily by deficits in the recognition of fear. Collectively, these results indicate disorganized processing of face stimuli in autistic individuals and suggest a mechanism that may subserve the social information processing deficits that characterize autism spectrum disorders.
LAPAROSCOPIC BILATERAL HAND ASSISTED NEPHRECTOMY FOR AUTOSOMAL DOMINANT POLYCYSTIC KIDNEY DISEASE: INITIAL EXPERIENCE

Purpose: The laparoscopic technique for bilateral nephrectomy in patients with autosomal dominant polycystic kidney disease is technically difficult. The procedure may be more acceptable if alterations to the technique made it safer and easier to perform. We describe our initial experience with, and the feasibility and potential benefits of hand assisted laparoscopic nephrectomy for approaching these large kidneys in patients with autosomal dominant polycystic kidney disease.Materials and Methods: This approach was successfully applied in 3 patients with end stage renal disease due to autosomal dominant polycystic kidney disease. After obtaining transumbilical pneumoperitoneum ports were placed in the umbilicus (12 mm.), sub-xiphoid in the midline (12 mm.) and subcostal in the midclavicular line on each side (12 mm.). The table was tilted 40 degrees away from the planned side of initial nephrectomy with the patient in the half lateral position. A 7 cm. midline incision was made that incorporated the umbil...
A Markovian Replacement Model with a Generalization to Include Stocking

The following model is considered: A machine is inspected at the beginning of discrete time periods and its operating state (condition) is determined. After each inspection a decision upon whether or not to replace the machine at the end of the period must be made. It is shown that under certain conditions on the costs and the transition distributions the optimal policy has a simple form. A generalisation to the case where one is allowed to stock reserve machines is also given.
Component-wise parameter smoothing for learning mixture models

In this paper, we propose a novel component-wise smoothing algorithm that constructs a hierarchy (or family) of smoothened log-likelihood surfaces. Our approach first smoothens the likelihood function and then applies the EM algorithm to obtain a promising solution on this smoothened surface. Using the most promising solutions as initial guesses, the EM algorithm is applied again on the original likelihood. This effective optimization procedure eliminates extensive search in the non-promising regions of the parameter space. Empirical results on some standard datasets show the reduction of the number of local maxima and improvements in the log-likelihood values.
Identification of the ligand binding site in Fas (CD95) and analysis of Fas-ligand interactions.

Fas (CD95), a member of the tumor necrosis factor receptor superfamily, and its ligand (FasL), a tumor necrosis factor-like protein, are intensely studied because their interaction on the cell surface is critical for the induction of programmed cell death (apoptosis) and the regulation of immune responses. The structure and specificity of the extracellular binding domains of Fas and its ligand were studied, in different laboratories, by combining molecular modeling, mutagenesis, and a variety of binding and functional experiments. Residues critical for the receptor-ligand interaction were identified and, in the absence of experimentally determined structures, binding sites and details of the Fas-ligand interactions were predicted. These studies provide an instructive example for the close combination of prediction and experiment and illustrate how insights into the structure and binding characteristics of Fas and its ligand were gradually refined. Discussed methodological aspects are representative of structure-function studies on extracellular domains of other single-path transmembrane proteins. Proteins 1999;35:475–482. © 1999 Wiley-Liss, Inc.