cssi/SciSciGPT-SciSciNet huggingface dataset:
Removal of ambient K+ inhibits net Na+ transport in toad bladder by reducing Na+ permeability of the luminal border.

Sodium crosses epithelia in two steps: an influx into the cell through the luminal membrane down an electrochemical gradient, and an energy-requiring efflux across the serosal border against a gradient. Koefoed-Johnsen and Ussing1 originally proposed that cellular efflux of Na+ at the serosal border of frog skin is coupled to K+ influx by an exchange pump. It was, therefore, assumed that the inhibition of active Na+ transport following the removal of K+ from the serosal side was due to a reduced pool of K+ available for the coupled exchange. Indirect evidence suggests that this is not correct. (1) K+ influx from the serosa does not correlate to any significant degree with active Na+ transport2–5. (2) Removal of Na+ as well as K+ from the serosal medium substantially reduces the inhibitory effect of K+ removal on active transport2,6. (3) One would predict that if K+ removal did inhibit active transport only at the serosal pump site, then as active transport decreased the ‘active transport pool’, that is, the mucosally derived cell Na+, would increase as it does with ouabain. Studies by Robinson and Macknight7, however, showed that the mucosally derived pool does not change on removal of external K+. Essig and Leaf2 suggested that removal of serosal K+ inhibited Na+ transport by decreasing the permeability of the luminal membrane. They showed that when K+ was removed from the serosa, there was a decrease in the amount of 22Na taken up into the tissue after exposure of the luminal surface to the isotope for 5 min. We have recently found that tissue uptake of 22Na after exposure of toad bladders to the isotope is linear with time for only up to 24 s. Because only the linear portion of the uptake is a measure of the Na+ flux across the luminal border8, it is clear that longer periods of uptake are more representative of the steady-state isotope distribution in the tissue. This value is controlled not only by the luminal permeability but also by the serosal permeability and the rate of net transport. These issues prompted us to re-investigate the effect of low external K+ on Na+ movement across the luminal border. We report here that the Na+ transport inhibition seems to be due to a reduced Na+ permeability at the luminal border.
Phragmén-Lindelöf principles for solutions of elliptic differential inequalities

On considere des operateurs differentiels elliptiques lineaires d'ordre 2: Lu=Σ i,j=1 n a i j∂ u 2u/∂x i ∂x j +Σ I=1 n bi∂u/∂x i +cu, ou les coefficients a i j, b i , c sont definis dans un domaine de R n . On etudie les fonctions barrieres pour de tels operateurs. On etablit des principes de Phragmen-Lindelof pour des points limites finis et le point limite a l'infini
Aesthetic fields: a two-dimensional lattice solution satisfying integrability

Abstract In our previous paper we obtained examples of lattice solutions to the aesthetic field equations. A drawback with these solutions was that the integrability equations were not satisfied. In this paper we find a solution to the aesthetic field equations which describes a two-dimensional lattice structure. The integrability equations are satisfied in this case. We work within a six-dimensional framework in this paper. Three of the coordinates are real and three of the coordinates are pure imaginary. It is a generalization of the Minkowski version of aesthetic field theory.
Eye movements during visual search for artistically embedded targets

Eye movements were measured as subjects searched for a word target embedded in line drawings. Time taken to find the target was directly related to the degree of embeddedness or target conspicuity. Detections were predicted by multiple-fixation clusters exceeding 400 msec within 3 deg of the target. Search errors resulted from faulty pattern recognition in which the target was fixated, but for dwell times shorter than the 400-msec detection threshold found for hits. Dwell time is taken to reflect recognition and decision processes used to discriminate real from potential targets. Several search tasks have shown that the conspicuity of the target, defined as the degree to which the target is embedded in the surround, directly influences target detection (Kundel & Nodine, 1978; Kundel, Revesz, & Graber, 1974). Embedded targets, because they have more features in common with the surround and there­ fore blend into it, are harder to find than nonembedded targets that stand out from the surround. The targets (the word NINA) in artist Al Hirschfeld's drawings, are noted for their lack of conspicuity because most of the features of the word are constructed of the same lines used to make up the picture. Finding NINAs is both entertaining and instructive, because it shows how the artist effectively uses the principle of embed­ ding to hide targets in an artistically rendered scene. In fact, and paradoxically, the "background" in which NINAs are embedded is usally considered the "fore­ ground" from both the artist's and the viewer's point of view, and the NINA targets are synonymous with Hirschfeld's signature. Other artists have also experi­ mented with the principle of embedding to hide figures in their art works. One of the best known examples is Salvador Dali's painting, "The Slave Market with Disappearing Bust of Voltaire." From these examples, it is clear that the artist has discovered that the principle of embedding depends on the interrelationship between target and background. The greater the overlap between these two feature sets, the greater the degree of embedding. In a similar way, military targets are embedded in scenic backgrounds using another invention of the artist: camouflage. In this case, the principle of embed­ ding may include not only overlap of target and back
Fatigue analysis of spot welds using a mesh-insensitive structural stress approach

Abstract This paper describes the application procedures of a nodal force based mesh-insensitive structural stress parameter for analysis of a comprehensive set of spot weld fatigue test data collected from a series of advanced high strength sheet steels. The structural stress parameter is calculated in an equilibrium sense in terms of bending and membrane components from nodal forces and moments at each grid point along the periphery of a weld nugget. Based on fracture mechanics considerations, an equivalent structural stress parameter is then used to take into account the effects of loading mode and sheet thickness on the fatigue of spot welded joints. The equivalent structural stress is proven effective in consolidating the large amount of fatigue data of spot welds for transformation induced plasticity (TRIP), dual-phase (DP), and high strength low alloy (HSLA) steels subjected to both tensile shear and coach peel loadings. As a result, a single master S–N can be established for fatigue design and life prediction of spot-welded structures.
Sampling Plans Which Approximately Minimize the Maximum Expected Sample Size

Abstract Let θ denote the unknown proportion of defectives in an indefinitely large population. A sampling plan is constructed which approximately minimizes the maximum expected sample size among all plans satisfying the conditions Pθ (plan will accept the population) ≥ 1− α if θ ≤ θ−1 Pθ (plan will accept the population) ≤ β if θ≥θ1.
Control Strategy for Fault-Tolerant Cascaded Multilevel Converter based STATCOM

Cascaded multilevel converters have been widely used in STATCOM application. Attentions were drawn to the issue of reliability because of the high number of power devices. In this paper, the concept of redundancy is applied to improve the reliability of CMC, a protection scheme to achieve HBBB redundancy in CMC-based STATCOM is proposed. The operating principle and control strategy are introduced and discussed. A 7-level CMC-based STATCOM simulation platform is set up. Controller for the system is designed. Proposed protection scheme is implemented. Simulation results verify the proposed HBBB redundancy protection scheme.
Evaluation of an Automated Pressure Ulcer Risk Assessment Model

The key to timely interventions and reducing avoidable incidence is the early identification of patients at risk for developing pressure ulcers. To enable the automatic detection of such patients a...
Control over uplifts and hassles and its relationship to adaptational outcomes

The relationship of perceived control over daily uplifts and hassles to depression and restraint was examined in a sample of 140 middle-class sixth graders. Results indicated that greater control over uplifts was associated with better functioning and lower control over hassles with poorer functioning, even after partialing out the respective number of uplifts and hassles reported. Moreover, when directly compared, control over uplifts showed more powerful associations with adaptational outcomes than did control over hassles. In a separate analysis, the number of uplifts over which children reported high control showed opposite relationships to adaptational outcomes than did the number of uplifts over which children reported low control. A different pattern appeared for hassles. Although the number of hassles with low control was associated with poorer functioning, the number of hassles over which children had high control was unrelated to adaptational outcomes. The possibility that control operates somewhat differently for positive and negative events is discussed.
Platelet-activating factor augments tumor necrosis factor and procoagulant activity.

Abstract Infusion of platelet activating factor (PAF) reproduces the host physiologic response to endotoxemia and sepsis. Tumor necrosis factor (TNF) and procoagulant activity (PCA) are two other potentially deleterious central inflammatory mediators produced in large quantities by tissue-fixed macrophages (Mφ). The relationship, if any, between PAF and TNF or PCA production is unknown. Rabbit alveolar Mφ were treated in vitro with PAF alone and prior to endotoxin (LPS). PAF alone had no effect on Mφ PCA or TNF. PAF (10−9−10−6M) cotreatment enhanced Mφ PCA and TNF levels in a dose response from two- to sixfold above that of LPS treatment alone. PAF (10−6M) pretreatment of Mφ at T -4 to -6 hr produces an eight- to ninefold enhancement in both TNF and PCA levels. Thus, both coincubation and pretreatment or “priming” of the Mφ with PAF prior to LPS stimulation greatly increase Mφ production of PCA and TNF. The ability to augment the production of these two potent inflammatory mediators may explain in part the mechanism of action of PAF in vivo.
Uterotrophic activity of polychlorinated biphenyls (PCB) and induction of precocious reproductive aging in neonatally treated female rats.

Abstract Polychlorinated biphenyls (PCBs) have been found to contaminate the ecosystem and reach both prenatal and postnatal individuals via the placental circulation and milk, respectively. Some PCBs also possess weak estrogenic activity. Experiments were devised to examine the estrogenic activity of Aroclors (Monsanto Co.) and their capacity to induce a permanently altered pattern of neuroendocrine reproductive function in female rats treated only during neonatal development. Aroclor 1221 at a dose of 1000 μg/kg body weight produced significant uterine growth 24 hr after treatment in weanling rats. This estrogenic PCB given to pups only on the second and third days of life induced precocious puberty, persistent vaginal estrus (PVE), and anovulation by 6 months of age; the latter end points are signs of reproductive again and do not normally occur in rats until later in life. Aroclors 1242, 1254, and 1260 did not produce a uterotrophic response in weanling rats at the doses tested nor did they induce the PVE syndrome when given to neonates. It is concluded that there is an association between the estrogenic activity of a PCB and its effectiveness in altering neuroendocrine differentiation and inducing premature reproductive aging.
The Nucleotide Binding Folds of the Cystic Fibrosis Transmembrane Conductance Regulator Are Extracellularly Accessible

Analysis of the primary sequence of the cystic fibrosis transmembrane conductance regulator (CFTR) has suggested the presence of two predicted cytoplasmic regions of the protein which are thought to be nucleotide binding folds (NBF1 and NBF2). Previous studies have shown that purified recombinant NBF1 can form anion conducting channels in planar phospholipid bilayers [Arispe et al. (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 1539−1543] and that the bacterial His P protein (analogous to a NBF) can be extracellularly labeled with a membrane-impermeant reagent [Baichwal et al. (1993) Proc. Natl. Acad. Sci. U.S.A. 90, 620−624]. Based on these observations, it is reasonable to hypothesize that the NBFs from the CFTR are associated with the plasma membrane and have extracellularly-accessible regions. Direct biochemical evidence for this was obtained by determining the ability of the individual NBFs, expressed in intact Hi5 cells, to be chemically modified with the membrane-impermeant reagent NHS-biotin. The result...
Circadian and menstrual cycle variation in serum ascorbic acid levels in baboons.

A report on circadian and menstrual cycle variation in serum ascorbic acid levels in baboons is presented. Ascorbic acid levels were determined every 6 hours over a 36-hour period and every other day throu ghout complete menstrual cycles in 5 normally cycling female baboons. No evidence of a circadian rhythm in ascorbic acid levels was seen. Ascorbic acid levels during the menstrual cycle did not vary markedly although periovulatory levels tended to be lower and a positive significant (p less than .05) regression coefficient was obtained during the luteal phase. The time required for disappearance of 1/2 of an im injection of 1 gm L-ascorbic acid during the follicular periovulatory and luteal phases was 70 62 and 67 minutes respectively. When diet and environment were rigidly controlled and the periovulatory period was accurately timed as a marker during the menstrual cycle there did not appear to be any relationship between physiologic levels of sex hormones and serum ascorbic acid levels.
Effect of L-asparaginase on carbohydrate metabolism.

Abstract Glucose tolerance tests and simultaneous serum insulin and human growth hormone (HGH) levels were determined in 4 patients undergoing cancer chemotherapy with L-asparaginase. A significant impairment occurred in the glucose tolerance test in two of these patients receiving L-asparaginase. Serum insulin levels decreased significantly in all patients. An additional patient had a very low serum insulin level despite severe hyperglycemia which preceded his death. In all patients HGH remained normal to low. It appears that the hyperglycemia which results from L-asparaginase therapy is due to a decrease in insulin synthesis.
Serotonin axons in the supra- and subependymal plexuses and in the leptomeninges; Their roles in local alterations of cerebrospinal fluid and vasomotor activity

Extensive plexuses of serotonin axons form a supra- and subependymal system in the walls of the ventricles, in the arachnoid sheath around major cerebral blood vessels, and in the pia over the spinal cord. These have been demonstrated by autoradiography after continuous intraventricular perfusions of exogenous [3H]5-HT in rats and monkeys. The axons accumulate 5,6-DHT rendering them electron opaque, but have no uptake systems for [3H]NE. After treatment with MAO inhibitors and [3H]5-HT, the axonal boutons contain large (70nm) variably dense synaptic vesicles, and small (35 nm) vesicles each equipped with a dense dot. The latter vesicles are not seen in untreated controls. Electrical stimulation in the raphe nuclei causes significant increases in axonal [3H]5-HT uptake indicating that the fibers originate in the raphe. Quantitatively, the supraependymal plexus is variable, profuse over the dorsal and ventral aqueductal surfaces, sparse over the lateral aspects. Individual raphe neurons have their specific uptake affinities for [3H]5-HT that are independent of tracer concentration or diffusion gradient. It is suggested that raphe neurons with low 5-HT uptake may utilize other neurotransmitters. Two new functional roles are proposed: (1) the serotonin ventricular and pial axons are probably important modifiers of local cerebrospinal fluid (CSF) composition so that regional CSF variations in 5-HT and its metabolites are highly probable; (2) the subarachnoid plexus around major cerebral vessels may contribute to local vasomotor action, thus affecting the cerebral blood flow. The possible significance of these serotonin systems for an understanding of certain neurological entities such as migraine and hemodynamic regulation in cerebral vascular disease is indicated.
BIFURCATION OF EQUILIBRIA IN MICROMACHINED ELASTIC STRUCTURES WITH ELECTROSTATIC ACTUATION

The determination of critical actuator voltages for the onset of "pull-in" or buckling of micromachined elastic structures or microelectromechanical systems (MEMS) with a finite number of electrostatic actuators is posed as a multiparameter bifurcation problem associated with a nonlinear partial differential equation. By making suitable approximations, the problem is reduced to one involving a multiparameter family of mappings on a bounded subset of a finite-dimensional Euclidean space RP into itself. Then the problem is reposed as one involving the intersection of level sets of certain functions whose levels correspond to the variable parameters (squares of actuator voltages). A sufficient condition for fold bifurcation when the actuator voltages exceed certain critical values is deduced using simple geometric arguments. The paper concludes with a discussion on the bifurcation of equilibrium of such systems for the limiting case where the number of actuators tends to infinity.
Experimental quantification of the plastic blunting process for stage II fatigue crack growth in one-phase metallic materials

Abstract The plastic blunting process during stage II fatigue crack growth was studied in pure polycrystalline Ni to investigate effects of strain localization and inelastic behavior on the kinematics of crack advance. Correlations were obtained between strain fields ahead of a fatigue crack, crack advance per cycle and crack growth kinetics. Strain fields were quantified using a combination of in situ loading experiments, scanning electron microscopy and digital image correlation for 8 m = 2 1 + 1 1 + n ′ , where n′ is the cyclic hardening exponent (0
Treatment of scapholunate dissociation by ligamentous repair and capsulodesis

We believe that direct scapholunate ligamentous repair, supported by a dorsal radioscaphoid capsulodesis, should be considered for the treatment of most scapholunate dissociations when there is no osteoarthritis, regardless of the time that has elapsed since injury. We treated 24 patients by this technique between 1972 and 1988. The records of 21 were available for study. Average time from injury to surgical treatment was 17 months (range, 1 to 84 months). Results were evaluated clinically and by means of patient questionnaire and x-ray films. The significant change in range of motion was a loss of palmar flexion, which averaged 11.5 degrees. Grip strength, pain, and x-ray appearance improved in all cases. Only one patient had to change occupations after surgery because of wrist symptoms. Three had minimal x-ray degenerative changes, which did not result in increased pain or in loss of motion and grip strength. There were no complications.
CHANGES IN THE PERMEABILITY OF PLANT CELLS TO P32O4 AND WATER AS A RESULT OF EXPOSURE TO OZONATED HEXENE (SMOG)

Artificial smog resulted in a decrease in the permeability of the cells of Pinto bean leaves to radioactive phosphate when the plants were exposed to a mixture of 1 p.p.m. of ozone with an excess of 1-n-hexene for periods up to 3 hr. Longer exposures resulted in a reversal of this effect and increased the permeability of the leaf cells to phosphate. This increased permeability was associated with the appearance of visible smog damage on the leaves. Potato-tuber disks showed similar effects from smog on uptake of P/sup 32/ from a buffer solution and on both uptake and loss of water over short periods of time.
The road to equal-norm Parseval frames

Abstract The construction of equal-norm Parseval frames is fundamental for many applications of frame theory. We present a construction method based on a system of ordinary differential equations, which generates a flow on the set of Parseval frames that converges to equal-norm Parseval frames. We developed this method to address a question posed by Vern Paulsen: How close is a nearly equal-norm, nearly Parseval frame to an equal-norm Parseval frame? The distance estimate derived here can be used to substantiate numerically found, approximate constructions of equal-norm Parseval frames. The estimate is valid for a fairly general class of frames — requiring that the dimension of the Hilbert space and the number of frame vectors is relatively prime. In addition, we re-phrase our distance estimate to show that certain projection matrices which are nearly constant on the diagonal are close in Hilbert–Schmidt norm to ones which have a constant diagonal.
The Process of Ethical Decision-Making: Experts vs Novices

As one approach to examining the way ethical decisions are made, we asked experts (i.e., ethicists, regulatory officials, and experienced researchers) and novices (i.e., inexperienced graduate students) to review a set of scenarios that depict some important ethical tensions in research. The method employed was “protocol analysis,” a talk-aloud technique pioneered by cognitive scientists for the analysis of expert performance. The participants were asked to verbalize their normally unexpressed thought processes as they responded to the scenarios, and to make recommendations for courses of action. We found that experts spent more time working through the decision-making process than novices and also raised substantially more concerns than novices. Differences also exist among the three groups of experts.
Communications: Bacteria in the Hemolymph of the Freshwater Prawn Macrobrachium rosenbergii

Abstract Bacteria from the hemolymph of the freshwater prawn Macrobrachium rosenbergii were identified and quantified. Total bacterial counts ranged from 0.0 to 4.6 × 105 cells/1.0 mL of hemolymph. Predominant bacteria isolated included Aeromonas spp., Bacillus sp., and Pseudomonas spp. No bacteria were found in the hemolymph of prawns without lesions. The predominant species of bacteria isolated from water samples of prawn culture ponds was a chitinoclastic Bacillus sp.
Effect of terminal perfluorocarbon chain containing mesogens on phase behaviors of chiral comb-like liquid crystalline polymers

A novel perfluorinated liquid crystal 4′-(2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluorooctanoyloxy)biphenyl-4-yl undec-10-enoate (PFOBU) was synthesized, which exhibited smectic C phase. Several liquid crystalline polymers (PI–PVI) were synthesized by use of poly(methylhydrogeno)siloxane, PFOBU, and cholesteryl 3-(4-allyloxy-phenyl)-acryloate. The chemical structures and liquid crystalline (LC) properties of the monomers and polymers, and some ferroelectric properties of the chiral smectic C (S C * ) phase were characterized by use of various experimental techniques. The effect of perfluorocarbon chains on phase behaviors of the fluorinated LC polysiloxanes was studied as well. PI and PII showed single chiral nematic (N*) mesophase when they were heated and cooled, but PIII, PIV, PV, and PVI containing more perfluorocarbon chain units exhibited S C * phase besides N* mesophase. Introduction of perfluorocarbon chain containing mesogens to the chiral cholesteryl-containing polymer systems resulted in a S C * mesophases, indicating that the fluorophobic effect could lead to microphase segregation and modifications of smectic mesophases from the chiral nematic phase.
Singing Practices in 10 Families with Young Children

This article addresses types and functions of singing practices in 10 families with 3-year-old children living in New York City, with illustrative cases of three families. Initial interviews were h...
An ion milling pattern transfer technique for fabrication of three-dimensional micromechanical structures

We describe a useful method of transferring mask patterns over large distances using ion milling. This technique exploits the anisotropy of a collimated ion beam to etch the projection of a stencil mask pattern into a thin film. This method avoids the difficulties associated with photoresist processing on highly nonplanar substrates, and thus provides an alternative process avenue for the development of three-dimensional microstructures. We demonstrate this technique, in a process including wet anisotropic silicon etching, by fabricating arrays of high aspect ratio barbs which are intended for use in tissue fasteners in biomedical applications. >
ROLE OF GRAVITY IN PREMIXED METHANE-AIR FLAME-VORTEX INTERACTIONS

Studies of flame-vortex interactions can improve our understanding of turbulent flames. Experiments conducted in a microgravity environment suggest that the flame-vortex interactions observed in Earth gravity may be complicated by the effects of buoyancy. Therefore, detailed, time dependent numerical simulations of flame-vortex interactions in different gravitational environments have been carried out. By comparing downward, upward and zero-gravity flamevortex interactions, additional insight has been gained. Our simulations show that in all cases, the final shape of the flame is strongly influenced by gravity. Phenomena such as pocket formation and flame quenching are observed to be essentially the same in both Earth gravity and zero gravity. Detailed comparisons of weak vortex-flame interactions in Earth and zero gravity indicate that the flame generated vorticity is not strongly associated with the hydrostatic pressure gradient.
Non-human primate model of Kaposi's sarcoma-associated herpesvirus infection

Since Kaposi's sarcoma-associated herpesvirus (KSHV or human herpesvirus 8) was first identified in Kaposi's sarcoma (KS) lesions of HIV-infected individuals with AIDS, the basic biological understanding of KSHV has progressed remarkably. However, the absence of a proper animal model for KSHV continues to impede direct in vivo studies of viral replication, persistence, and pathogenesis. In response to this need for an animal model of KSHV infection, we have explored whether common marmosets can be experimentally infected with human KSHV. Here, we report the successful zoonotic transmission of KSHV into common marmosets (Callithrix jacchus, Cj), a New World primate. Marmosets infected with recombinant KSHV rapidly seroconverted and maintained a vigorous anti-KSHV antibody response. KSHV DNA and latent nuclear antigen (LANA) were readily detected in the peripheral blood mononuclear cells (PBMCs) and various tissues of infected marmosets. Remarkably, one orally infected marmoset developed a KS-like skin lesion with the characteristic infiltration of leukocytes by spindle cells positive for KSHV DNA and proteins. These results demonstrate that human KSHV infects common marmosets, establishes an efficient persistent infection, and occasionally leads to a KS-like skin lesion. This is the first animal model to significantly elaborate the important aspects of KSHV infection in humans and will aid in the future design of vaccines against KSHV and anti-viral therapies targeting KSHV coinfected tumor cells.
LC resonant clock resource minimization using compensation capacitance

Distributed-LC resonant clock distribution is a viable technique to reduce clock distribution network (CDN) dynamic power. However, resonant clocks can require significant on-chip resources to form the inductors and decoupling capacitors which discourages adoption. This paper uses a compensation capacitor (C c ) to reduce the overhead of the on-chip inductor and capacitor resources without changing the performance of a distributed-LC resonant clock. Analysis on the ISPD clock benchmarks show nearly 12% reduction in passive device area compared to previous resonant clocks while still saving 49.9% power over traditional buffered clocks.
Primary drug treatment for glaucoma: beta-blockers versus other medications.

This set of Viewpoints articles examines the merits of beta-blockers versus other medications as the primary drug treatment for glaucoma. Ophthalmologists must balance issues such as efficacy, compliance, cost, and side effects when deciding on the appropriate medication to prescribe. Dr. Stamper stresses the advantages of tailoring the choice of medication to the needs of the individual patient. Drs. Wigginton and Higginbotham review the benefits of beta-blockers and present some of the disadvantages of the non-beta-blocker class of medications. ( Surv Ophthalmol 47: 63-73, 2002. © 2002 by Elsevier Science Inc. All rights reserved.)
Cognition Is Not Modified by Large but Temporary Changes in Sex Hormones in Men

Context: Little is known about the role of testosterone and estradiol on cognition in healthy older men. Objective: The cognitive effects of increasing or lowering testosterone or estradiol were examined. Design: Cognition was assessed before and after 6 wk of double-blind placebo-controlled hormone modification. Setting: The study was conducted at an academic medical center. Participants: Healthy older (ages 60–80 yr) and younger men (ages 25–35 yr) were recruited from the community. Intervention: Men were randomized to one of four treatments: 1) maintain testosterone and estradiol at eugonadal levels for young men (GnRH agonist + testosterone gel); 2) block testosterone’s conversion to estradiol (GnRH agonist + testosterone gel + aromatase inhibitor); 3) induce hypogonadism (GnRH agonist alone); and 4) all placebo. Main Outcome Measures: Measures of executive function, memory, and spatial cognition were obtained before and after treatment. Hormone levels were obtained 10 times over the course of the stu...
Longitudinal Profiles of Ephemeral Streams in Southeastern Arizona

Two longitudinal profile segments of different concavity in ephemeral streams heading in the mountains of southeastern Arizona are related to the longitudinal variation of drainage area (A) , bed-material size ( D mm ), and channel width: depth ratio (W/D) . These parameters approximate discharge, sediment load, and roughness, which have been found to control stream profiles in other regions, but were unavailable for this ephemeral-stream study. Inclusion of basin relief (R) and lithology allowed development of statistically significant equations for both segments of streams draining granitic and sedimentary terrains: Sedimentary concave: Sedimentary straight: Granitic concave: Granitic straight: Profiles of streams in two additional mountain ranges were predicted from the equations with an accuracy within the limits of accuracy of the field and map measurements. Precipitation-elevation relations have no apparent effect on the accuracy of the predictions or on stream-profile concavity.
Evolution and distribution of the ospC gene, a transferable serotype determinant of Borrelia burgdorferi.

Borrelia burgdorferi, an emerging bacterial pathogen, is maintained in nature by transmission from one vertebrate host to another by ticks. One of the few antigens against which mammals develop protective immunity is the highly polymorphic OspC protein, encoded by the ospCgene on the cp26 plasmid. Intragenic recombination among ospCgenes is known, but the extent to which recombination extended beyond the ospClocus itself is undefined. We accessed and supplemented collections of DNA sequences of ospCand other loci from ticks in three U.S. regions (the Northeast, the Midwest, and northern California); a total of 839 ospC sequences were analyzed. Three overlapping but distinct populations of B. burgdorferi corresponded to the geographic regions. In addition, we sequenced 99 ospCflanking sequences from different lineages and compared the complete cp26 sequences of 11 strains as well as the cp26 bbb02loci of 56 samples. Besides recombinations with traces limited to the ospC gene itself, there was evidence of lateral gene transfers that involved (i) part of the ospCgene and one of the twoflanks or (ii) the entireospCgene and different lengths of bothflanks. Lateral gene transfers resulted in different linkages between the ospCgene and loci of the chromosome or other plasmids. By acquisition of the complete part or a large part of a novel ospCgene, an other- wise adapted strain would assume a new serotypic identity, thereby being comparativelyfitter in an area with a high prevalence of immunity to existing OspC types. IMPORTANCE The tick-borne zoonosis Lyme borreliosis is increasing in incidence and spreading geospatially in North America. Further understanding of the evolution and genetics of its cause, Borrelia burgdorferi, in its environments fosters progress to- ward ecologically based control efforts. By means of DNA sequencing of a large sample collection of the pathogen from across the United States, we studied the gene for the bacterium's highly diverse OspC protein, protective immunity against which devel- ops in animals. We found that the distributions and frequencies of types of OspC genes differed between populations of B. burg- dorferiin the Northeast, the Midwest, and California. Over time, OspC genes were transferred between strains through recombi- nations involving the whole or parts of the gene and one or bothflanks. Acquisitions of OspC genes that are novel for the region confer to recipients unique identities to host immune systems and, presumably, selective advantage when immunity to existing types is widespread among hosts.
Treatment of fetal tachycardia.

i n h t o c ntroduction he goal of fetal tachycardia management and treatment is he near-term delivery of a nonhydropic fetus in sinus hythm. On the one hand, fetal demise occurs in as many as 0% of fetuses with sustained tachycardia and hydrops. On he other hand, every antiarrhythmic medication has the otential to cause fatal proarrhythmia or serious and lasting ide effects, such as hypothyroidism, to the mother, the etus, or both. Therefore, the diagnosis of tachycardia must e accurate (supraventricular tachycardia [SVT] or ventriclar tachycardia [VT]), the antiarrhythmic medication necssary, safe, and effective, and the monitoring and care of he mother and the fetus before and after in utero cardioersion vigilant and comprehensive.
Effects of stocking density on the performance of Pacific white shrimp Litopenaeus vannamei cultured under pond and outdoor tank conditions using a high soybean meal diet

Abstract The objective of this study was to evaluate the effect of stocking density on the growth performance and economic feasibility for the culture of Litopenaeus vannamei fed plant based diets and cultured in production ponds and an outdoor tank system. Juvenile shrimps (0.015 g initial weight) were stocked in sixteen 0.1 ha ponds with stocking densities of 17, 26, 35, and 45 shrimp m − 2 and cultured under standardized pond production conditions for 16 weeks. Daily feed rates were predetermined using expected growth per week of 1.3 g, a feed conversion ratio (FCR) of 1.2, and an estimated survival rate of 78%. Additionally, juvenile L. vannamei (2.8 g initial weight) were stocked into 24,800-L tanks at the densities of 15, 25, 35, 45, 55, and 65 shrimp m − 2 with 4 replicates per treatment and cultured for 10 weeks. Daily feed inputs were calculated based upon an expected weekly weight gain of 1.3 g and an expected FCR of 1.2. At the conclusion of the trials, final production, final mean weight, FCR, size distribution and survival were determined. The results for the pond study demonstrated that there was a trend of negative correlation between stocking density and growth. Mean final weight (± SD) of shrimp across treatments ranged from 20.70 to 25.25 g. Survival ranged from 58.0 to 65.1%, and FCR was between 1.17 and 1.54. These differences were not significant (P ≥ 0.10) among treatments, however, higher stocking density resulted in significantly greater yield. Final production was between 2660 and 6149 kg ha − 1 . There were no significant differences in partial returns among different densities for the pond study. The results for the outdoor tanks showed that shrimp growth were inversely related to stocking density, with mean final weight ranged from 13.42 to 16.13 g. Final biomass ranged between 286.15 and 637.20 g tank − 1 . There was a negative correlation between stocking density and FCR with FCR ranging from 1.15 to 1.54. Survival ranged from 93.4 ± 5.6 to 100.0 ± 0.0%, however, there was no significant effect of stocking density on survival rate. Additionally, there were no significant differences in production value and partial income data among treatments under pond production study.
In Defense of a Test of the Linkage Hypothesis

I. Linkages, 335. — II. (Dis)Aggregation, 336. — III. A tempest in a teapot, 337. — IV. Conclusion, 342.
Improved method for artificial insemination in the great apes.

Artificial insemination in the great apes has not achieved its potential as a tool in maintenance of the endangered captive population. Three factors can influence the success rate of artificial insemination: sperm preparation, site of insemination, and timing of insemination. We have tried to optimize methods regarding these three steps. A modified method for insemination is described which has resulted in a 21% success rate (six term pregnancies from 29 inseminations) in the chimpanzee and which has successfully initiated a pregnancy in a gorilla.
Increased sensitivity of Aspergillus flavus and Aspergillus parasiticus aflatoxin biosynthesis polyketide synthase mutants to UVB light

One strategy to reduce aflatoxin contamination of maize and cottonseed is to introduce spores of non-aflatoxigenic strains as competitors. Using isogenic mutants we show that, upon 5 or 20 min exposure to 302 nm (UVB) light, the viability of conidia of Aspergillus flavus and Aspergillus parasiticus mutants lacking the ability to accumulate any aflatoxin precursor metabolite is reduced five-fold compared to that of aflatoxin-producing strains or pigmented mutants that accumulate aflatoxin precursors. This result suggests that the long-term viability of introduced non-aflatoxigenic competitor strains may be lower than that of natural aflatoxin-producing isolates when exposed to sunlight.
A fuzzy logic method for modulation classification in nonideal environments

In this paper, we present a fuzzy logic modulation classifier that works in nonideal environments in which it is difficult or impossible to use precise probabilistic methods. We first transform a general pattern classification problem into one of function approximation, so that fuzzy logic systems (FLS) can be used to construct a classifier; then, we introduce the concepts of fuzzy modulation type and fuzzy decision and develop a nonsingleton fuzzy logic classifier (NSFLC) by using an additive FLS as a core building block. Our NSFLC uses 2D fuzzy sets, whose membership functions are isotropic so that they are well suited for a modulation classifier (MC). We establish that our NSFLC, although completely based on heuristics, reduces to the maximum-likelihood modulation classifier (ML MC) in ideal conditions, In our application of NSFLC to MC in a mixture of /spl alpha/-stable and Gaussian noises, we demonstrate that our NSFLC performs consistently better than the ML MC and it gives the same performance as the ML MC when no impulsive noise is present.
Statistics of impact crater accumulation on the lunar surface exposed to a distribution of impacting bodies.

Impact crater size vs incidence analyzed statistically in study of validity of time dependence on saturation for moon and Mars
Explaining Demise Among Nonprofit Organizations

Explaining Demise Among Nonprofit Organizations reports on a study of closure of nonprofit organizations in the Minneapolis–St. Paul metropolitan area from 1980 to 1994. The theoretical literature focusing on the behavior of individual and populations of organizations suggests eight reasonably distinct theoretical explanations why nonprofit organizations close. These theories include the liabilities of newness and small size, the inability to reproduce commitment, intraorganizational conflict, inability to mobilize human resources, lack of legitimacy, inability to compete for scarce or depleted financial resources, lack of connections to other organizations, and the completion of the organization’s mission. Longitudinal data collected by Joseph Galaskiewicz on organizational characteristics provide the opportunity to determine which theories have the most fidelity in terms of explaining the closure of nonprofit organizations. Of a random sample of 229 public charities interviewed in 1980, 73 had exited the panel by the end of the study period in 1994. Of these, 37 closed their doors. This study focuses on those 37 organizations that closed. Several kinds of data contribute to a final accounting of which theories are supported in the sample studied. Exit interviews with representatives from 31 of the closed organizations yield factors that interviewees believe were most important in explaining the closure of their organizations. Formal analyses of the organizational narratives provide initial insights into the reasons that organizations closed. In addition, the dissertation presents an analysis of longitudinal survey data. Rather than analyzing cause on a case-by-case basis, this approach yields probabilistic explanations about the relationships between variables hypothesized to vary with organizational closure. Results from the various analyses show consistent support for the liabilities of small size and youth, as well as the liability of competing in a sparse resource niche. Analysis of the open
Developing a Promotional Strategy: Important Questions for Social Marketing

Health practitioners often use the terms marketing and promotion interchangeably. Yet, promotion is just one element of an overall marketing strategy. To realize the greatest impact there must be a combination of all the marketing components, including product, price, place, and promotion. The purpose of this article is to clarify the role of promotion and describe key elements of developing a promotional strategy within the broader context of a social marketing initiative.
1-bromo-2-chlorocyclopropene--A new cycloproparene synthon. Synthesis of 1H-Cyclopropa[b]phenanthrene

Abstract Treatment of 1-bromo-2,2-dichloro(trimethylsilyl)cyclopropane (2) with tetra- n -butylammonium fluoride in tetrahydrofuran yields 1-bromo-2-chlorocyclopropene (1). 1H-Cyclopropa[b]phenanthrene (3) can be prepared by aromatization of the Diels-Alder adduct of 1 and 1,2-dimethylene-3,5,6,7,8,9-hexahydronaphthalene (6) using DDQ followed by potassium t -butoxide in tetrahydrofuran.
REGULATION OF THE HUMAN POLYMORPHONUCLEAR LEUKOCYTE INFLAMMATORY RESPONSE BY INHIBITORS OF ARACHIDONIC ACID METABOLISM

AbstractPerturbation of the neutrophil membrane by opsonized zymosan particles activates the cell's “respiratory burst.” Associated with this activation process is the generation of highly reactive oxygen products, including superoxide, and the release of lysosomal enzymes. Membrane activation also stimulates arachidonic acid metabolism and the generation of a wide variety of products through both the lipoxygenase and cyclooxygenase pathways. In isolated human neutrophils, we have evaluated the effects inhibitors of cyclooxygenase and lipoxygenase upon opsonized zymosan stimulated chemiluminescence, superoxide generation, oxygen consumption, and beta-glucuronidase release. Nordihydroguaiaretic acid (NDGA), an inhibitor of the lipoxygenase enzyme, suppressed chemiluminescence, superoxide generation, oxygen consumption, and beta-glucuronidase release. Both indomethacin, a cyclcooxygenase inhibitor, and 5,8,11,14 -eicosatetraynoic acid (ETYA) an inhibitor of both cyclooxygenase and lipoxygenase, inhibited al...
Anesthetic management and outcome following noncardiac surgery in nonparturients with Eisenmenger's physiology

Abstract Study Objective: To evaluate the perioperative risk to nonparturients with Eisenmenger's physiology for noncardiac surgical procedures. Design: Retrospective chart review. Setting: University-affiliated hospital. Patients: 12 nonparturients with Eisenmenger's physiology who underwent 25 noncardiac surgical procedures requiring care by an anesthesiologist. Measurements and Main Results: Preoperative, intraoperative, and postoperative records were retrospectively analyzed. Data examined included patient age, gender, symptoms, laboratory values, monitors used, surgical procedure, and outcome. Twenty-five procedures were performed on 12 patients; 13 procedures were performed with general anesthesia, 6 with peripheral nerve blocks, 5 with sedation by an anesthesiologist with or without local anesthetic infiltration, and one with epidural anesthesia. One patient died perioperatively. Review of the literature revealed two deaths in 32 procedures for nonparturients with Eisenmenger's physiology undergoing noncardiac surgery. Conclusions: A variety of anesthetic techniques and drugs may be used successfully in nonparturients with Eisenmenger's physiology undergoing noncardiac surgery. Although the study group is small, the perioperative mortality risk is lower than that for parturients undergoing either labor and delivery or cesarean section and is probably in the range of approximately 10%.
On the Use of Term Rewriting for Performance Optimization of Legacy HPC Applications

Preparing codes for next generation supercomputer systems is anticipated to require significant changes to the optimization strategies employed in established HPC applications. In this paper, we present our experience in applying term rewriting transformations for the optimization of such applications. We have designed application-specific term rewriting transformations to improve the scalability, enhance locality and reduce the communication overhead of the Self-Consistent Field computational chemistry benchmark. We present the rationale for the use of term rewriting in this manner, the design of our transformations, and the much enhanced performance of the resulting code.
CT and MR findings in diffuse cerebral histiocytosis: case report.

Intracranial involvement with histiocytosis is usually limited to the hypothalamus and associated with extensive extracra­ nial disease. We report the CT and MR findings in a patient with biopsy-proved histiocytosis presenting as multifocal in­ tracranial involvement without any systemic disease. While extrahypothalamic CNS involvement by histiocytosis is well recognized (1-9], infiltrative brain involvement in the absence of systemic disease is unusual. Case Report
Toward an Effective Ebola Virus Vaccine

Long-term control of viral outbreaks requires the use of vaccines to impart acquired resistance and ensuing protection. In the wake of an epidemic, established immunity against a particular disease can limit spread and significantly decrease mortality. Creation of a safe and efficacious vaccine against Ebola virus (EBOV) has proven elusive so far, but various inventive strategies are now being employed to counteract the threat of outbreaks caused by EBOV and related filoviruses. Here, we present a current overview of progress in the field of Ebola virus vaccine development.