cssi/SciSciGPT-SciSciNet huggingface dataset:
Mathematical model that characterizes transmitral and pulmonary venous flow velocity patterns

The transmitral and pulmonary venous flow velocity (TMFV and PVFV, respectively) patterns are related to the physiological state of the left heart by use of an electrical analog model. Filling of left ventricle (LV) through the mitral valve is characterized by a quadratic Bernoulli's resistance in series with an inertance. Filling of the left atrium (LA) through the pulmonary veins is represented by a lumped network of linear resistance, capacitance, and inertance. LV and LA are each represented by a time-varying elastance. A volume dependency is incorporated into the LV model to produce physiological pressure-volume loops and Starling curves. The state-space representation of the analog model consists of 10 simultaneous differential equations, which are solved by numerical integration. Model validity is supported by the following. First, the expected effects of aging and decreasing LV compliance on TMFV and PVFV are accurately represented by the model. Second, the model-generated TMFV and PVFV waveforms fit well to pulsed-Doppler recordings in normal and postinfarct patients. It is shown that the TMFV deceleration time is prolonged by the increase in LV compliance and, to a lesser extent, by the increase in LA compliance. A shift from diastolic dominance to systolic dominance in PVFV occurs when LA compliance or pulmonary perfusion pressure increases or when LV compliance or mitral valve area decreases. The present model should serve as a useful theoretical basis for echocardiographic evaluation of LV and LA functions.
Participation for the Handicapped.

(1979). Participation for the Handicapped. Journal of Physical Education and Recreation: Vol. 50, Including Leisure Today, pp. 81-82.
Impedance and force-field control of the index finger module of a hand exoskeleton for rehabilitation

For rehabilitation robots to be successful, a control system that results in safe, comfortable and effective interaction between the robot and subject is necessary. We present two types of torque-based controllers for the index finger module of a hand exoskeleton for rehabilitation. Impedance control applies a position-dependent torque at the joints, while keeping the interaction with the finger compliant. Force-field control, on the other hand, applies a position-dependent normal and tangential torques to track a contour in the joint angle space. We also present self-guided impedance control wherein hemiparetic subjects could guide their impaired hand with their healthy hand by using active and passive versions of our device. Experiments with a healthy subject showed that the device could render a range of impedances from low to high. For accurate trajectory tracking high impedance is needed because the inherent finger stiffness varies significantly, however, high impedance increases the torque applied when the finger motion is impeded. On the contrary, force-field control is safer for subjects whose joint show involuntary locking (e.g. spastic joints) and does not apply increased torques during stalled motion, however, provides limited control over the velocity. These results suggest that impedance control would be better suited for therapy where the goal is to train for time-critical tasks and force-field control would work where coordination between the joints is important.
Achievement Motivation and Quality of Selling Performance: An Exploration

In today’s rapidly changing selling climate characterized by increasing physical separation of salespeople from their managers and greater salesperson empowerment, performance outcomes depend to a large extent upon the degree to which salespeople are able to sustain their self-motivation. This paper takes an exploratory look at one aspect of salespeople’s self-motivation, their achievement motivation, in relation to their job performance. It explores the way components of achievement motivation contribute to the quality of salespeople’s performance.
Global Administrative Law and the FDA’s Collaborative Agreements with International Regulatory Partners

Abstract This chapter examines the diversity and objectives of the FDA's international agreements.
A German Way of War

DISCUSSION A German Way of War? German Atrocities, 1914. A History of Denial. By John Horne and Alan Kramer. New Haven and London: Yale University Press. 2001. xv + 608 pp. US $40.00 (hardback). Is it too soon to retire the Sonderweg? We may have forgotten how much that dark narrative of German history is owed, not just to Germany’s invasion of Belgium in 1914, but to the crimes of its troops, beginning on August 5, there and in France. Villages were looted and razed, hostages used as human shields, civilians shot, bayoneted, and confined to buildings which were then set alight. Children, including seven babies in Les Rivages, were among the 6,500 victims. Especially during the first three weeks, such violence was ‘endemic throughout the German army’ (p. 76), involving about half of its 300 regiments on the Western Front. The ‘proximate cause’ of these outrages was anxiety during the great gamble of the Western invasion (p. 42). Pillaging was ‘the natural consequence of armies outstripping their supply trains’ (p. 119); rage, fuelled by alcohol, the not unnatural consequence of meeting unexpectedly stiff Belgian resistance. But underlying these obvious explanations lay the German army’s belief that its progress was being sabotaged by civilian snipers (francs-tireurs); that their wounded were being mutilated by innocent-looking maidens and children; that they were confronted, in short, with the same kind of Volkskrieg that had beset them in France in 1870–71. The belief was false, sparked in most cases by panic at friendly fire. But along a front of more than 500 kilometres hysteria spread from foot soldiers to command: ‘a massive case of collective self-suggestion, probably unparalleled in a modern army. A million men were swept by a delusion %’ (p. 77). Within two weeks it encom- passed the home front as well. It was this astonishing ‘myth complex’ that stimulated a young Marc Bloch to embark upon his investigations into the history of rumour, irrationality, and mentalite´s. It stimulated German officers to issue orders which underwrote the initially spontaneous ‘reprisals’ with an official policy of exemplary massacre. The documentation of these atrocities is only the beginning of what, in lesser hands, could easily have become three books. The authors’ hearts are less in German History Vol. 22 No. 1 GH: german history 10.1191/0266355404gh302xx  2004 The German History Society GH$$$$302P
Vaginal cuff dehiscence after robotic total laparoscopic hysterectomy.

BACKGROUND Vaginal cuff dehiscence with small bowel evisceration after hysterectomy is a rare event that may be occurring more frequently with the advent of robotic laparoscopic hysterectomies.
Transport of ethanolamine and its incorporation into the variant surface glycoprotein of bloodstream forms of Trypanosoma brucei

The membrane-attached form of the variant surface glycoprotein (mf-VSG) of bloodstream forms of Trypanosoma brucei is anchored to the plasma membrane by a hydrophobic C-terminal lipo-oligosaccharide containing ethanolamine. Analysis by polyacrylamide gel electrophoresis showed that several different cloned T. brucei strains (strain EATRO 110 and variants 117 and 118 of strain 427) incorporated [3H]ethanolamine into both mf-VSG and the soluble VSG derived from it, but not into other proteins. Other trypanosomatids, e.g. Leishmania mexicana promastigotes, T. cruzi epimastigotes, and T. brucei procyclic forms, did not incorporate ethanolamine into cellular proteins. Thus, [3H]ethanolamine can be used as a specific biosynthetic label for T. brucei VSG polypeptides. The time course of incorporation of [3H]ethanolamine into VSG showed a lag period of about 15 min. Double-labelling experiments using [3H]ethanolamine and H3[32P]O4 demonstrated that ethanolamine labelled only the C-terminal moiety and was not incorporated into other portions of the VSG molecule. Cellular uptake of ethanolamine occurred via a specific carrier-mediated transport system having a Vmax of 132 pmol min-1 mg-1 protein and a Km of 3.7 microM. The properties of this transport system are consistent with the possibility that ethanolamine is derived entirely from the host.
642: Transcriptomics and proteomics ensemble analyses reveal serological protein panel for preeclampsia diagnosis

reveal serological protein panel for preeclampsia diagnosis Linda Liu, Matthew Cooper, Ting Yang, Jun Ji, Qiaojun Wen, Gongxing Chen, Alex Morgan, David Stevenson, Xuefeng Ling, Atul Butte Stanford University School of Medicine, Departments of Pediatrics, Stanford, CA, Stanford University School of Medicine, Departments of Surgery, Stanford, CA, Carmenta Bioscience, R&D, Stanford, CA OBJECTIVE: Preeclampsia is a condition arising from poor placentation and manifests itself as hypertension and proteinuria later in pregnancy. There are currently no specific laboratory based tests to diagnose preeclampsia for timely management or use of interventions. As a result, preeclampsia is a leading cause of preterm birth as well as maternal and fetal death. Our objective is to develop a serological protein assay to allow early recognition and referral of preeclamptic patients to Maternal Fetal Medicine specialists. STUDY DESIGN: Candidate biomarkers were revealed by ensemble analysis of gene expression and proteomics profiling of preeclampsia samples. Biomarkers were further qualified with enzyme-linked immunosorbent assays (ELISA) using serum samples from 33 preeclampsia subjects and 31 pregnant controls matched by parity, ethnicity, and gestational age (range 24-40 weeks). A five-protein serological panel, comprised of both novel and investigational proteins, was constructed by the application of a genetic algorithm optimized for its ability to accurately diagnose preeclampsia as defined by the area under the receiving operating characteristic curve. RESULTS: We observed better clustering and separation between samples from preeclamptic and non-preeclamptic patients compared to previously described, investigational diagnostic tests. Separation between patients groups was more pronounced earlier in gestational age. CONCLUSION: We have identified a serological protein panel capable of diagnosing both early and late onset preeclampsia. Further characterization of the novel panel analytes yielded mechanistic insights in preeclampsia, therefore, explaining the observed sensitivity and specificity across gestational ages. Future prospective validation can drive the translation of our serological panel into practical bedside clinical utilities for preeclampsia care. The work was supported by grants from the March of Dimes and Stanford University Spark Program.
Evolution of Resistance and Change in Relative Density in a Culex tarsalis (Diptera: Culicidae) Population Under Heavy Insecticidal Control

A mixed population of Culex tarsalis Coquillett, Culex quinquefasciatus Say, Culex peus Speiser, and Culex erythrothorax Dyer breeding in a sewage-treatment lagoon was subjected with increasing frequency to treatments with organophosphate larvicides during 1981–84. C. tarsalis , rare in 1981 (9% of total), had become the most abundant species by 1984 (84% of total), displaying high levels of larval resistance to chlorpyrifos (64-fold), methyl parathion (57-fold), temephos (42-fold), fenthion (41-fold), and malathion (36-fold).
NEW GRADUATE ORIENTATION PROGRAM IN A GERIATRIC PSYCHIATRIC INPATIENT SETTING

With the geriatric population increasing, so will their needs for mental health care. However, attracting nurses to work with mentally ill older adults can be challenging. This article describes and illustrates methods successfully used by one hospital to attract, orient, and mentor new graduate nurses to work in geropsychiatric nursing--the New Graduate Residency Program (NGRP). The importance of supportive collaborative roles within nursing leadership staff is emphasized. Although the NGRP is a viable option for meeting the needs of older patients, additional strategies are needed to increase the numbers of geropsychiatric nurses overall, and these are discussed.
Evaluation of Dietary Protein Levels for White Leghorns in the Grower and Subsequent Layer Periods

Abstract RECENT literature on the effect of protein levels on the overall performance of chickens in grower and/or layer periods shows a wide disparity in experimental design. For simplicity and clarity of presentation the investigators and their designs are shown in Table 1. As indicated in the table, different protein levels were fed at different ages under varying management practices. However, none of the studies were designed to test the effect of pullets reared on litter and fed varying protein levels at different ages, with subsequent transfer to layer cages and fed several protein levels. Accordingly, experiments were designed to study the effect of this treatment on grower and layer performance. EXPERIMENTAL PROCEDURE Day-old S.C. White Leghorn strain A pullets were used in years 1 and 2 (experiment 1) and day-old S.C.W.L. strains B and C in year 2 (experiment 2); both experiments were set up in March one year apart. . . .
Erosion effects on carbon dioxide concentration and carbon flux from an Ohio Alfisol.

Carbon dioxide concentrations in soil both reflect and influence soil biological activity and C flux to the atmosphere, We hypothesized that erosion affects CO 2 concentration and C flux from the soil surface because of its effects on soil temperature and water regimes. The soil air concentrations of CO 2 and corresponding temperature and water contents were monitored on slight (SLI), moderate (MOD), severe (SEV), and depositional (DEP) phases at 2-wk intervals between May 1996 and June 1997. The ambient soil CO 2 concentration and CO 2 -C flux were determined using gas chromatograph analyses. Seasonal patterns in soil air CO 2 concentrations (ranging from a winter low of 0.56 mL L -1 to a summer high of 20.90 mL L -1 ) predominated over more subtle differences (20-80% variation) due to erosion phase effects. Significantly greater (by 12-37%) CO 2 concentrations for SEV and MOD phases over SLI and DEP were observed mainly during the summer. The effects of the erosion phase on soil CO 2 concentrations appeared to be indirect through its impacts primarily on soil temperature and, presumably, soil biological activity. Soil air CO 2 concentrations were significantly correlated with soil temperature (R 2 = 0.61) and CO 2 -C (R 2 = 0.65) flux from the soil surface but not with soil water content. Both linear and second-order polynomial regression equations using soil temperature predicted soil CO 2 concentration.
The kinematics of dense clusters of galaxies. 3: Comparison with cosmological models

We compare the combined distribution of 31 group and 25 cluster velocity dispersions with the ensemble of 32 models for the formation and evolution of large-scale structure examined by Weinberg & Cole (1992). The models include Gaussian and non-Gaussian initial fluctuations, different power law spectra (n = -1, n = 0, n = -2, 'pancake'), flat (Omega = 1) and open (Omega = 0.2) cosmologies, and unbiased (b(sub 8) = 1) and biased (b(sub 8) = 2) galaxy formation. The set of initial conditions we test, although limited, samples enough parameter space to indicate which general classes of models are consistent with the data. The two Gaussian, n = -1 models which best approximate the standard and open Cold Dark Matter (CDM) models do not match the observed distribution of velocity dispersions; models with b(sub 8) = 2 and Omega = 1 ('standard') or b(sub 8) = 1 and Omega = 0.2 ('open') predict too large a ratio of low to high velocity dispersion systems. A 'COBE-normalized' CDM model with b(sub 8) = 1 and Omega = 1 produces clusters with velocity dispersions higher than those measured. All three models overestimate the total abundance of systems.
The unitary dual for complex classical Lie groups

In this paper we classify the unitary spectrum of the complex classical groups. Let G be any complex simply connected semisimple Lie group. There are two well known ways of constructing unitary representations from lower groups; unitary induction from a parabolic subgroup and complementary series. A reasonable way to describe the unitary dual is to find a distinguished set of representations for each group such that every other unitary representation is obtained from this set by the above constructions from strictly smaller parabolic subgroups. This is entirely similar to the classification of admissible modules where the distinguished representations are the discrete series. For integral infinitesimal character, such a set is provided by the special unipotent representations introduced in [BV1]. Their existence and unitarity was conjectured earlier by [A]. They were shown to have many interesting properties such as the fact that their annihilator is a maximal primitive ideal. From this it was possible to obtain character formulas for them. However it is clear that this set is not large enough to describe the entire unitary spectrum. For example in type C the metaplectic representation is not special unipotent or even one of the larger class of representations considered in [A]. The definition of special unipotent representations suggests that one should consider representations with maximal primitive ideal and infinitesimal character as small as possible. It is not clear which of them should be unitary. Imposing the condition that the annihilator be a completely prime ideal, which is necessary for unitarity, does not seem to be very helpful either. Thus one is left with the task of explicitly computing the g-invariant form and ruling out the cases when it is indefinite. This is an almost impossible calculation. A rough estimate says that one needs to compute signatures on the K-types in the principal series which have length < II 2p ql.
Muscle synergies during voluntary body sway: Combining across-trials and within-a-trial analyses

We investigated co-varied changes in muscle activity during voluntary sway tasks that required a quick shift of the center of pressure (COP). We hypothesized that multi-muscle synergies (defined as task-specific covariation of elemental variables, muscle modes) stabilize a COP location in the anterior–posterior direction prior to a voluntary COP shift and that during the shift the synergies would weaken. Standing subjects performed two tasks, a cyclic COP shift over a range corresponding to 80% of the maximal amplitude of voluntary COP shift at 1 Hz and a unidirectional quick COP shift over the same nominal amplitude. The cyclic sway task was used to define muscle modes (M-modes, leg and trunk muscle groups with parallel scaling of muscle activation level within a group) and the relations between small changes in the magnitudes of M-modes [in the principal component analysis (PCA), the M-mode magnitudes are equivalent to PC scores] and COP shifts. A novel approach was used involving PCA applied to indices of muscle integrated activity measured both within a trial and across trials. The unidirectional sway task was performed in a self-paced (SP) manner and under a typical simple reaction time (RT) instruction. M-modes were also defined along trials at those tasks; they have been shown to be similar across tasks. Integrated indices of muscle activity in the SP-sway and RT-sway tasks were transformed into the M-modes. Variance in the M-mode space was partitioned into two components, one that did not affect the average value of COP shift (V UCM) and the other that did (V ORT). An index (ΔV) corresponding to the normalized difference between V UCM and V ORT was computed. During steady-state posture, ΔV was positive corresponding to most M-mode variance lying in a sub-space corresponding to a stable COP location across trials. Positive ΔV values have been interpreted as reflecting a multi-M-mode synergy stabilizing the COP location. The magnitude of ΔV was larger in SP trials than in RT trials. During voluntary COP shifts, the ΔV magnitude dropped to zero or even became negative. We conclude that M-mode synergies stabilize COP location during quiet standing, while these synergies weaken or disappear during fast voluntary COP shifts. Under RT conditions, the COP stabilizing synergies were weaker supposedly to facilitate a quick COP shift without time for preparation. The suggested method of M-mode identification may potentially be applied to analysis of postural synergies in persons with impaired postural control such as elderly persons, persons with atypical development, or in the course of rehabilitation after an injury.
Axon arbors and synaptic connections of a vulnerable population of interneurons in the dentate gyrus in vivo.

The predominant γ-aminobutyric acid (GABA)ergic neuron class in the hilus of the dentate gyrus consists of spiny somatostatinergic interneurons. We examined the axon projections and synaptic connections made by spiny hilar interneurons labeled with biocytin in gerbils in vivo. Axon length was 152–497 mm/neuron. Sixty to 85% of the axon concentrated in the outer two thirds of the molecular layer of the dentate gyrus. The septotemporal span of the axon arbor extended over 48–82% of the total hippocampal length, which far exceeds the septotemporal span of axons of granule cells whose complete axon arbors extended over 15–29%. A three-dimensionally reconstructed 216-μm-long spiny hilar interneuron axon segment in the outer third of the molecular layer formed an average of 1 synapse every 5.1 μm. Of the 42 symmetric (inhibitory) synapses formed by the reconstructed segment, 88% were with spiny dendrites of presumed granule cells, and 67% were with dendritic spines that also receive an asymmetric (excitatory) contact from an unlabeled axon terminal. Postembedding GABA-immunocytochemistry revealed that 55% of the GABAergic synapses in the outer third of the molecular layer were with spines. Therefore, in the outer molecular layer, spiny hilar interneurons form synaptic contacts that appear to be positioned to exert inhibitory control near sites of excitatory synaptic input from the entorhinal cortex to granule cell dendritic spines. These findings demonstrate far-reaching, yet highly specific, connectivity of individual interneurons and suggest that the loss of spiny hilar interneurons, as occurs in temporal lobe epilepsy, may contribute to hyperexcitability in the hippocampus. J. Comp. Neurol. 445:360–373, 2002. © 2002 Wiley-Liss, Inc.
Molecular Analysis of Cocaine-Induced Endothelial Dysfunction: Role of Endothelin-1 and Nitric Oxide

Cocaine remains the most frequently used illicit substance. Although cocaine-induced atherosclerosis is well documented, its mechanism of action on human vascular endothelial cells has not been determined. Nitric oxide (NO) and endothelin-1 (ET-1) are involved in endothelial cell activation and leukocyte recruitment. The present study monitored the effects of cocaine on NO and ET-1 production in human aortic endothelial cells (HAECs) and the effects of sodium nitroprusside (SNP) and BQ-123 on leukocyte adhesion to HAECs. Acute exposure to cocaine (1 and 3 muM) significantly increased ET-1 production (2-fold) and ET-1 receptor type-A (ET(A)R) protein expression, within 6-12 h. Cocaine exposure for a longer duration (24-72 h) showed a temporal decrease in both NO production and endothelial NO-synthase (eNOS) expression. The cocaine-mediated suppression of NO was ameliorated by co-treatment of cells with the ET(A)R blocker, BQ-123 (5 muM). Furthermore, both short-term (24 h) and long-term (72 h) exposure to cocaine increased endothelial adhesion of monocytes (U937 cells) by 20% and 40%, respectively, which were also suppressed by BQ-123 and SNP co-treatment. These data suggest that a concomitant increase in both ET-1 and ET(A)R expression in cocaine exposed HAECs may enhance signaling via the ET(A)R which decreases eNOS expression and NO production, and ultimately results in endothelial activation and leukocyte adhesion. Our findings implicate a molecular mechanism of action of cocaine and a therapeutic effect of ET(A)R-specific inhibitor in suppressing the cocaine-induced endothelial dysfunction.
Limit laws for record values

{Xn,n⩾1} are i.i.d. random variables with continuous d.f. F(x). Xj is a record value of this sequence if Xj>max{X1,…,Xj−1}. Consider the sequence of such record values {XLn,n⩾1}. Set R(x)=-log(1−F(x)). There exist Bn > 0 such that XLnBn→1. in probability (i.p.) iff XLnR-1(n)→1 i.p. iff {R(kx)−R(x)}R12(kx) → ∞ as x→∞ for all k>1. Similar criteria hold for the existence of constants An such that XLn−An → 0 i.p. Limiting record value distributions are of the form N(-log(-logG(x))) where G(·) is an extreme value distribution and N(·) is the standard normal distribution. Domain of attraction criteria for each of the three types of limit laws can be derived by appealing to a duality theorem relating the limiting record value distributions to the extreme value distributions. Repeated use is made of the following lemma: If P{Xn⩽x}=1−e-x,x⩾0, then XLn=Y0+…+Yn where the Yj's are i.i.d. and P{Yj⩽x}=1−e-x.
The Mn effect on magnetic structure of FeMn-B amorphous metals

Fe-rich Fe-B amorphous metals exhibit approximately collinear magnetic structure. When a certain amount of Fe atoms are replaced with Mn, the magnetic structure of the alloys is found to become non-collinear. We performed electronic structure calculations using the locally self-consistent multiple scattering (LSMS) method for supercell samples generated by ab initio molecular dynamics simulation using the Vienna Ab-initio Simulation Package (VASP). We present the distribution of moment sizes and angular distributions in the FeMn-B amorphous metal samples. We discuss the Mn effect on the magnetic structure of the alloys.
Changes in Starch Pasting Properties Due to Sugars and Emulsifiers as Determined by Viscosity Measurement

The effects of sugars, emulsifiers, and their interactions on starch pasting properties were determined by the Rapid Visco-Analyser (RVA). Solutions of 50% sugars in water were used. The disaccharides, sucrose and lactose, delayed pasting more than did the monosaccharide, dextrose. Sugars’effects on starch pasting delay and on starch paste consistency varied with the starch. Addition of the same emulsifier (1%) to different starches did not result in the same change in paste consistency in the presence of high amounts of sugar. Both sucrose ester F-160 (SE) and polysorbate 60 (PS) reduced the hot paste consistency of starch-sugar mixtures, with SE having a greater effect than PS.
On Nonsingular Regular Magic Squares of Odd Order

Abstract Using centroskew matrices, we provide a necessary and sufficient condition for a regular magic square to be nonsingular. Using latin squares and circulant matrices we describe a method of construction of nonsingular regular magic squares of order n where n is an odd prime power.
Development of visual acuity in Rhesus monkeys deprived of patterned light during early infancy

Six monkeys given diffused light from birth to 20 or from birth to 60 days of age were found to have low visual acuity when first tested at these ages. With experience in patterned light their acuities improved consistently and at a rate comparable to that of normally reared monkeys.
Engineering size-scaling of plastic deformation in nanoscale asperities

Size-dependent plastic flow behavior is manifested in nanoindentation, microbending, and pillar-compression experiments and plays a key role in the contact mechanics and friction of rough surfaces. Recent experiments using a hard flat plate to compress single-crystal Au nano-pyramids and others using a Berkovich indenter to indent flat thin films show size scaling into the 100-nm range where existing mechanistic models are not expected to apply. To bridge the gap between single-dislocation nucleation at the 1-nm scale and dislocation-ensemble plasticity at the 1-μm scale, we use large-scale molecular dynamics (MD) simulations to predict the magnitude and scaling of hardness H versus contact size lc in nano-pyramids. Two major results emerge: a regime of near-power-law size scaling H ≈ lc−η exists, with ηMD ≈ 0.32 compared with ηexpt ≈ 0.75, and unprecedented quantitative and qualitative agreement between MD and experiments is achieved, with HMD ≈ 4 GPa at lc = 36 nm and Hexpt ≈ 2.5 GPa at lc = 100 nm. An analytic model, incorporating the energy costs of forming the geometrically necessary dislocation structures that accommodate the deformation, is developed and captures the unique magnitude and size scaling of the hardness at larger MD sizes and up to experimental scales while rationalizing the transition in scaling between MD and experimental scales. The model suggests that dislocation–dislocation interactions dominate at larger scales, whereas the behavior at the smallest MD scales is controlled by nucleation over energy barriers. These results provide a basic framework for understanding and predicting size-dependent plasticity in nanoscale asperities under contact conditions in realistic engineered surfaces.
P3-S7.05 Phenotypic characterisation of clinical trichomonas vaginalis isolates among AAWSW in sexual partnerships

Background Trichomonas vaginalis (TV) is the most common non-viral sexually transmitted infection in the world. TV prevalence in US women is consistently highest among African Americans (AA). However, little data exists on the risk of TV infection among women who have sex with women (WSW) and the mechanism of transmission is poorly understood. The goal of this study was to evaluate the concordance of TV isolates among AAWSW involved in sexual partnerships using the random amplified polymorphonuclear DNA (RAPD) technique. Methods AAWSW involved in sexual partnerships and participating in a cross-sectional study of STI prevalence rates at the Mississippi State Department of Health STD clinic in Jackson, MS, were selected for this study if both women in the partnership were infected with TV. All women completed a confidential survey asking detailed sexual history questions about female and male partners during the past 12 months. The RAPD technique utilising six unique PCR primers was performed on TV clinical isolates from each sexual partnership. RAPD amplicons were collated and categorised to determine genetic similarity between isolates from paired couples. Results TV isolates from three paired couples were included in this study. RAPD profiling demonstrated that only one out of the three pairs of TV isolates was concordant see Abstract P3-S7.05 figure 1. Within this concordant pair, both women reported engaging in oral sex and sharing wet towels during sexual activity. One woman in this pair reported recent sex with a male partner while the other woman denied history of other sexual partners during the past 3 months and had not had sex with a male partner in 5 years. Additionally, a follow-up visit of one of the members of this concordant union demonstrated a RAPD pattern discordant with previous findings indicating that the individual9s initial treatment was successful and that she had acquired a new TV infection. Conclusions Given the phenotypic similarity of banding patterns within one AAWSW sexual partnership, female to female transmission of TV may have occurred. The frequency of TV transmission between WSW is unknown at this time; however, the use of RAPD appears to be informative for differentiating isolates of TV. A prospective study examining the epidemiology and incidence of TV infection among WSW is necessary.
Independence, Conformity, and Civil Liberties: Some Implications from Social Psychological Research

A free society requires independent initiatives as well as regularities of conduct, otherwise it will stagnate. Authentic independence reflects critical judgment in responding to social demands rather than merely rejecting them. A climate of free expression is essential to independence and the perpetuation of civil liberties. Although social psychology has tended to emphasize processes of conformity, as much attention is needed to factors facilitating independence. Six impediments to independence are: risks of dissapproval, lack of perceived alternatives, fear of disrupting the proceeding, absence of shared communication, inability to feel responsibility, and sense of impotence. To overcome these impediments socialization oriented to the critical evaluation of alternatives is necessary, including practice in making judgments and greater rewards for independent initiatives.
Antarctic climate cooling and response of diatoms in glacial meltwater streams

[1] To understand biotic responses to an Antarctic cooling trend, we analyzed diatom samples from glacial meltwater streams in the McMurdo Dry Valleys, the largest ice-free area in Antarctica. Diatoms are abundant in these streams, and 24 of 40 species have only been found in the Antarctic. The percentage of these Antarctic diatom species increased with decreasing annual stream flow and increasing harshness of the stream habitat. The species diversity of assemblages reached a maximum when the Antarctic species accounted for 40–60% of relative diatom abundance. Decreased solar radiation and air-temperatures reduce annual stream flow, raising the dominance of these Antarctic species to levels above 60%. Thus, cooling favors the Antarctic species, and lowers diatom species diversity in this region.
Case challenges in shoulder surgery: what would you do?

The management of complex shoulder issues was discussed in an interactive case presentation session. Patient scenarios discussed included reoperation of a rotator cuff repair with a subscapularis tear; uncemented hemiarthroplasty presenting with pain and osteolysis; severe osteoarthritis with all nonoperative options exhausted; rheumatoid arthritis with pain and diminished function; and significant pain, limited motion, and weakness in an active patient.
Collective Enhancement of Radial Transport in a Nonneutral Plasma

Experimental evidence is presented showing that collective effects may enhance the radial transport produced by an asymmetric perturbing field applied to a rotating nonneutral plasma column. The field asymmetry drives an asymmetric plasma mode and the mode field produces additional transport. Of particular interest for confinement systems is the existence of a zero-frequency plasma mode which can be driven by static field asymmetries. Applications to tandem mirrors are discussed.
Stringent constraints on cosmological neutrino-antineutrino asymmetries from synchronized flavor transformation

We assess a mechanism which can transform neutrino-antineutrino asymmetries between flavors in the early universe, and confirm that such transformation is unavoidable in the near bi-maximal framework emerging for the neutrino mixing matrix. We show that the process is a standard Mikheyev-Smirnov-Wolfenstein flavor transformation dictated by a synchronization of momentum states. We also show that flavor ``equilibration'' is a special feature of maximal mixing, and carefully examine new constraints placed on neutrino asymmetries. In particular, the big bang nucleosynthesis limit on electron neutrino degeneracy xi_e < 0.04 does not apply directly to all flavors, yet confirmation of the large-mixing-angle solution to the solar neutrino problem will eliminate the possibility of degenerate big bang nucleosynthesis.
Diadenosine tetraphosphate‐induced inhibition of ATP‐sensitive K+ channels in patches excised from ventricular myocytes

Abstract Diadenosine 5',5''-P1,P4-tetraphosphate (Ap4A) has been termed 'alarmone' due to its role in intracellular signaling during metabolic stress. It is not known whether Ap4A could modulate ATP-sensitive K+ (KATP) channels, a family of channels regulated by the metabolic status of a cell. We applied the single-channel patch-clamp technique to measure the effect of Ap4A on KATP channels. When applied to the intracellular side of patches, excised from guinea-pig ventricular myocytes, Ap4A inhibited KATP channel activity, in a reversible and concentration-dependent (half-maximal concentration approximately 17 microM) manner. We conclude that Ap4A, a naturally occurring diadenosine polyphosphate, is actually an inhibitor of the myocardial KATP channel.
Heterogeneity of the Association between Lower Respiratory Illness in Infancy and Subsequent Asthma

Viral lower respiratory tract illnesses occurring during the first years of life are associated with increased risk of subsequent asthma, but the mechanisms involved have not been completely elucidated. The available evidence suggests that the factors that explain this connection are heterogeneous. Children who start life with lower levels of airway function appear to be more prone to transient forms of wheezing in the first years of life. "Intrinsic" bronchial hyperresponsiveness, that is, that measured shortly after birth and unrelated to markers of atopy, has been reported to predict both early life wheezing and wheezing occurring during the early school years, independent of atopy. It has also been suggested that both decreased interferon-gamma responses measured before any viral lower respiratory illness and increased interferon-gamma responses measured at the time of the illness may predispose to such illnesses. Children in whom the former mechanism is involved should be expected to be more atopic later in life, whereas those with the latter mechanism should be less likely to be atopic. This may explain why early viral respiratory illnesses have been found to be both protective against and a risk factor for subsequent atopy in different studies. Current evidence thus suggests that different and often apparently contradictory mechanisms related to airway function, structure, and immune responsiveness may explain the association between viral lower airway illness in early life and subsequent asthma. Future preventive and therapeutic strategies will need to address the specific mechanisms that explain this association in different groups of subjects.
Urinary Excretion of Prostaglandin F2α and 6‐Keto‐Prostaglandin F1αa during Volume Expansion in Patients with Glomerulonephritis

Thirteen patients with active IgA glomerulonephritis (IgA GN), ten patients with a history of Henoch-Schonlein glomerulonephritis (HS GN) and nine healthy controls were studied during hydropenia (HP) and 3% volume expansion (VE) with isotonic saline. Clearance of inulin and para-aminohippurate, urinary excretion of Na, immunoreactive prostaglandin F2 alpha (PGF2 alpha) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) were determined. The patients with a history of HS GN had normal blood pressure and renal function. As in the controls, the urinary excretion of PGF 2 alpha decreased and the excretion of 6-keto-PGF1 alpha increased during VE. In the patients with IgA GN the glomerular filtration rate (GFR) was normal, markedly reduced and supernormal. Five patients had hypertension and an increased NA excretion in relation to the GFR during VE. As a group, the patients with IgA GN increased their urinary excretion of 6-keto-PGF1 alpha during VE, while the excretion of PGF2 alpha did not change. In relation to the GFR, the urinary excretion of PGF2 alpha and 6-keto-PGF1 alpha was markedly increased in two patients with low GFR, which implies that these substances play a role in advanced renal disease. VE had little effect on PG excretion in these patients. In the hypertensive patients the urinary excretion of PGF2 alpha and 6-keto-PGF1 alpha was the same as in those with normal blood pressure. PGs are therefore not likely to mediate the increased natriuretic response to VE in hypertension.
Gastric mucosal responses to intrahepatic portosystemic shunting in patients with cirrhosis.

Abstract Background & Aims: The response of gastric mucosal lesions in cirrhotic patients with portal hypertension, namely, portal hypertensive gastropathy (PHG) and gastric vascular ectasia (GVE), to transjugular intrahepatic portosystemic shunts (TIPS) is not known. Methods: Clinical and laboratory evaluation, upper gastrointestinal endoscopy, and Doppler ultrasonography were performed before placement of TIPS and 6 weeks, 3 months, and 6 months after TIPS in 54 patients. Thirty patients had mild PHG, 10 had severe PHG, and 14 had GVE. Results: Approximately 75% of the patients with severe PHG responded to TIPS as shown by improvement in endoscopic findings and by a decrease in transfusion requirements; 89% of patients with mild PHG had endoscopic resolution. Patients with GVE had neither endoscopic resolution nor a decrease in transfusion requirements after TIPS. There was no difference in mortality between the 2 groups. Conclusions: The results support the position that severe PHG and GVE may be different lesions. Mild and severe PHG respond to TIPS. Because GVE does not respond to TIPS, we recommend that TIPS be avoided for the treatment of gastrointestinal bleeding associated with GVE. GASTROENTEROLOGY 2000;118:905-911
Supramolecular Ribbons. Crystal Structure and Spectroscopic Properties of 2,2′-Bipyrroyl

A crystal structure determination of 2,2′-bipyrroyl (1; 2,2′-dipyrryl-diketone, bis (2-pyrrolyl)ethanedione) and its spectroscopic properties in solution are reported. In the crystal, 1 self-assembles via hydrogen bonding into supramolecular ribbons that extend indefinitely through the crystal lattice. The observed molecular conformation is one where each pyrrole ring and adjacent carbonyl group are co-planar (torsion angle ∼ 0.9°), with the N-H pointing in the same direction as the C=O. The two carbonyls have a transoid but not co-planar geometry with a torsion angle of ∼128°. Adjacent molecules in the crystal are linked by pairs of intermolecular hydrogen bonds, pyrrole NH to carbonyl oxygen, to form a matrix of polymeric chains that lie like neatly stacked, parallel streams of ribbons. Molecular mechanics calculations on the monomer indicate an intra-molecularly hydrogen bonded planar conformation (sp, ap, sp) at the global energy minimum. In CHCl3, 1 is monomeric according to vapor pressure osmometry (MWobs=179±10 vsċMWcalc=188). In THF, the measured molecular weight is 340±15, which corresponds best to one molecule of 1 solvated by two THF molecules (MW=322 for C10H8N2O4ċ2 C4H8O) rather than to a dimer.
Synthesis and reactivity of technetium(VII) imido complexes

Abstract The synthesis, characterization and electrochemistry of a series of new technetium complexes, Tc(NAr)3X and Tc(NAr′)3X (X = OSiMe3, alkyl, I), is reported. These complexes are shown to be resistant to reduction and moderately air-sensitive. The siloxy complex Tc(NAr)3(OSiMe3) (1a) reacts with fluoride ion to give the tris(imido)oxo anion [TcO(NAr)3]−. Less sterically hindered M(Nar′)3(OSiMe3) complexes react with Ar′NCO in a net [2+2] fashion to give the urylene complexes M(NAr′) 2 (NAr′C(O)N Ar′) (OSiMe3) (2a, M = Tc; 2b, M = Re). The X-ray crystal structures of 1a, 2b and (Tc(NAr)3I (4a) suggest that the imido ligands moderate their level of electron donation to reflect the electronic requirements of the metal and the ancillary ligands.
Ice-marginal environment and ecosystem prior to initial advance of the late Palaeozoic ice sheet in the Mount Butters area of the central Transantarctic Mountains, Antarctica

Basal rocks of the Upper Carboniferous to Lower Permian Pagoda Formation at Mount Butters provide an unusual view of periglacial conditions in the central Transantarctic Mountains region prior to the initial advance of the Gondwanide ice sheet. These rocks were deposited on a high relief unconformity that developed on granite. Deposition within relief on the unconformity, possibly in the lee of a granite buttress, protected the rocks from erosion during subsequent overriding by the ice sheet. The succession reflects deposition in a glacial-fed to ice-contact lake that contained a freshwater crustacean fauna. Centimetre- to decimetre-scale basal layers include breccia and coarse-grained sandstone. The occurrence of breccia resting on weathered granite suggests sedimentation as scree and as mass flow deposits. Overlying decimetre-to metre-scale stratified diamictites interbedded with metre-scale, coarsening-upward successions of siltstone to cross-laminated sandstone suggest lacustrine deposition by suspension settling, rain out of ice-rafted debris, and deltaic progradation. Thin zones with abundant conchostracans and/or with prolific trace fossils, in addition to less common remains of other crustaceans, attest to the presence of a low diversity benthic fauna. Conchostracans are concentrated in a series of thin beds that reflect moderately lengthy, perhaps seasonal, periods of free-flowing water. Patchy vertical and lateral distribution of intense bioturbation and profuse trace fossils probably reflect repeated colonization events during times of favourable environmental conditions. Massive diamictite overlies the basal rocks and indicates that the ice-marginal lake was subsequently overridden by the late Palaeozoic ice sheet. Occurrences of lodgement till, glacitectonite and deformation till suggest deposition from temperate or warm-based ice, whereas underlying lacustrine and deltaic deposits, along with a crustacean and trace fossil fauna, suggest temperate periglacial conditions. Previous studies have stressed that upper Palaeozoic glacigenic deposits in Antarctica, and in Gondwanaland, record deglaciation events. In contrast, rocks at Mt. Butters provide an unusual glimpse into an ice-margin lake and its fauna just prior to ice sheet advance.
Autologous pericardium versus a xenograft substitute in myocardial wound healing

This study compared repair of myocardial wounds covered with autologous pericardium to healing of wounds covered with glutaraldehyde-preserved bovine pericardium in an experimental canine model. Right (RV) and left (LV) full thickness ventriculotomies were made and closed. In the control group (n = 12), the pericardium was closed over the wound; in the experimental group (n = 12), wounds were covered with bovine pericardium. Animals were sacrificed at 14, 21, 28, and 42 days. After excising the pericardium, 6 mm punch biopsies of normal RV, RV wound, normal LV, and LV wound were assayed for hydroxyproline (HPro). Both autologous and bovine pericardium became densely adherent to the wounds. Bovine pericardium was mildly adherent over unwounded areas, while autologous pericardium was usually free. Normal RV contained more than twice as much HPro as normal LV (5.4 +/- 0.57 micrograms/mg vs 1.7 +/- 0.35 micrograms/mg, P less than 0.0002). A gradual rise in HPro over time was seen in both groups, but this increase was statistically significant only at 42 days (P less than 0.05). There was no significant difference in HPro between wounds covered with autologous pericardium and those covered with bovine grafts (P = 0.13) at any of the sample times in this study. In this experimental canine model, the pericardium does not appear to play a prominent role in myocardial wound healing by contributing collagen-producing fibroblasts. Furthermore, the bovine pericardial xenograft becomes densely adherent to LV and RV incisions. In the clinical setting, such may make reoperation more hazardous when the heart has been previously incised or coronary bypass grafts have been constructed.
Real time spectroscopic ellipsometry of sputtered CdTe, CdS, and CdTe1−xSx thin films for photovoltaic applications

Real time spectroscopic ellipsometry (RTSE) has been applied to study the deposition of polycrystalline CdTe, CdS, and CdTe 1-x S x thin films on crystalline silicon wafer substrates as well as the formation of CdS/CdTe and CdTe/CdS heterojunctions, all using a magnetron sputtering process. For CdTe and CdS, the key process variable is deposition temperature (T). The nucleation and growth behaviors of CdTe and CdS show strong variations with T and this influences the ultimate grain size of the polycrystalline films. For the co-sputtered CdTe 1-x S x alloys, the key variables are the rf power levels applied to the CdTe and CdS targets and thus the re-sulting composition x. The dielectric functions of the alloys have been used as a database for real time investigation of inter-diffusion at the CdS/CdTe and CdTe/CdS heterojunctions.