cssi/SciSciGPT-SciSciNet huggingface dataset:
Friction Coefficient Measurement of Hydrogel Materials on Living Epithelial Cells

Soft biomaterials are often used in applications that involve contact and relative motion against biological tissues, as well as complicated and variable environments. The friction coefficient of these contacts involving living human cells is of key importance in the analysis and success of these devices. This work measures the contacting friction coefficient between soft hydrogel biomaterial surfaces against live human corneal epithelial cells using a custom micro-tribometer. The friction coefficients were of the order of μ = 0.03 for contacts that did not cause gross destruction of the cell layer. Damage to the confluent cell layer was assessed using a Trypan blue stain with optical microscopy. This damage was quantified statistically using image-processing software. The damage was also correlated to in situ friction measurements, with the lowest friction values seen on undamaged cells and higher friction on damaged regions.
The Economics of Corporate Reorganization

I. The meaning of "failure" and "reorganization," 29. — II. The economics of reorganization. Liquidation value of the assets: specialization, 32; separability, 33; costs of liquidation, 34. — Value in reorganization, 35. — Uncertainty of computations, 37. — Readjustment of claims: the "absolute priority rule," 38. — Difficulties: conflicting valuations, 40; inducing new investment, 41. — III. Comparison of procedures. The major problems to be solved: deciding upon reorganization or liquidation, 44; procuring new capital, 46; dealing with dissenting minorities, 47; ensuring independent and disinterested review, 48; keeping costs down, 49.
Club drug use among young men who have sex with men in NYC: a preliminary epidemiological profile.

This paper describes findings from a study of young men who have sex with men (YMSM) in New York City. Using a cross-sectional design and a community-based targeted sampling approach, a total of 569 YMSM were recruited during 2000 and 2001 for a structured survey interview. High rates of lifetime exposure to a variety of club drugs (including methamphetamine, ketamine, and MDMA) are observed in the overall sample. Among those who use club drugs on a chronic basis (N = 145), we found high rates of a prior suicide attempt (including high rates of multiple suicide attempts), high rates of lifetime exposure to multiple types of drugs, high rates of current poly drug use (including multiple types of club drugs), and high rates of current depressive symptoms. Chronic club drug users had a mean CES-D score of 8.5 and nearly two-thirds had a score of 7 or more. Although high rates of condom use are reported in some types of sexual exchanges, data show multiple types of sexual risk among chronic club drug users, including high rates of unprotected anal intercourse (UAI) with most frequent partners and comorbid drug use among both YMSM and their sexual partners.
Measurement of adenosine by capillary zone electrophoresis with on-column isotachophoretic preconcentration

An on-column isotachophoretic (ITP)-capillary electrophoresis (CE) system capable of preconcentrating polyhydroxyl species is reported. The ITP-CE system utilizes borate complexation of the neutral diol species to form anionic compounds that can be directly separated by CE. Borate buffer fuctions as both the terminating electrolyte for the ITP preconcentration and the operating buffer for the subsequent CE separation. Isotachophoretic preconcentration allows injection volumes as large as 50% of the column volume, without compromising separation integrity, to yield detection limits about 70-fold lower than direct CE separation (with borate operating buffer). In this paper we also present an application of the ITP-CE system, with laser-induced fluorescence (LIF) detection, to the quantitative analysis of adenosine from urine. Nanomolar concentration levels of adenosine are successfully derivatized with chloroacetaldehyde (CAA) to form a fluorescent derivative whose spectral characteristics match the HeCd laser. The technique is shown to be capable of quantitative measurement of adenosine as low as 10−9 M, the levels expected in plasma and urine.
SEARCH BREADTH AND THE COST OF SEARCH.

We draw attention to an overlooked, yet key theoretical determinant of innovation search -- the cost of search. We argue that the cost of broadening search inhibits exploration and identify two cos...
On the interconnection of metal-metal bonding in dimers and solid resistivity, magnetic susceptibility, and normal superconductivity

Abstract The bonding of a model dimer is analyzed and the physical meaning of the VB-CI responsible for binding is interpreted. Then the electronic structure of transition metal dimers is analyzed and it is concluded that these are held together by ns -gas pairs which interact with the (n-1) d -groove pairs or electrons in a way determined by the electronic nature of the constituent atoms. Next a transition is made to the solid, which is envisioned as an aggregate of dimers where the electric field of all the atomic cores causes breakage of a fraction of the gas pairs. The next step is the interpretation of resistivity: high resistivity is associated with gas pairs which interact strongly with groove pairs and the core, while good conductors have the gas pairs disengaged from them. The final conclusion is that superconductivity is a phenomenon expected from metals with gas pairs which are neither too tightly bound to the core and to groove pairs (poor conductors) nor disengaged from them (good conductors). This sets the stage for an interpretation of high T c superconductivity in ceramics, presented in a following paper.
Agar gel electrophoresis of proteolytic enzymes in gastric juice of patients with chronic gastritis.

Agar gel electrophoresis with proteolytic digestion of albumin substrate and subsequent Chromoscan analysis of the agar slide, were used to study the proteolytic enzymes of gastric juice in 28 patients with atrophic gastritis with or without intestinal metaplasia, 7 patients with chronic superficial gastritis and 6 with a normal gastric mucosa. Five proteolytic enzyme spots, designated I through V in order of decreasing anodic mobility, were found in gastric juice from normal controls. Of these spots, Spot II (pepsin) was largest; Spot III (presumably gastricsin) was next in prominence, followed by Spot I (prepepsin, presumably degradation product or products of pepsin). Spot IV, of slow anodic mobility (pepsinogen), was rather small and sometimes absent, and Spot V was seen only rarely and in traces. In 12 of 14 cases of atrophic gastritis without intestinal metaplasia, Spots II and III were diminished in area and well demarcated. Spot IV was often large and Spot I was most often absent. Twelve cases of atrophic gastritis with intestinal metaplasia and 2 cases of gastric atrophy showed either: a) absence of all five spots (5 cases, including 3 of pernicious anemia) or b) a marked reduction of area and good demarcation of Spots II and III with absence or reduction of Spot I (8 cases); in 1 case, Spots I, II, and III were absent. In 4 cases of atrophic gastritis with or without intestinal metaplasia (of which 3 were associated with gastric cancer) a distinct Spot V was seen. In 6 of the 7 cases of chronic superficial gastritis, a normal pattern was seen; in 1 case the pattern resembled that seen in atrophic gastritis without metaplasia. We believe this method of analyzing proteolytic enzymes in gastric juice is of interest for evaluating chronic gastritis.
Contact analysis of laser textured disks in magnetic head–disk interface

Friction and wear behavior of a laser textured disk surface in contact with a magnetic head slider depends on the shape and size of the laser bumps, number of bumps, and mechanical properties of the disk and slider surfaces. In this study, analytical expressions for the height distributions of sombrero- and donut-shaped laser bumps, commonly used in the disk applications, have been developed. These expressions are used to generate the bumps on the computer. Contact analyses of these surfaces are carried out using analytical and numerical methods. Expressions for calculation of meniscus forces for spherical bumps and cylindrical rims are derived. An analytical method is developed to calculate meniscus forces, contact area and optimum number of bumps of a constant height, as a function of bump size and shape to minimize plastic deformation and stiction. A generalized numerical model, developed earlier for random surfaces, is used for contact analysis of bumps with a height distribution. Design curves are generated to estimate optimum number of bumps for a given height distribution, as a function of yield stress of the disk surface. Contact areas (pressure) and meniscus forces of the two bump geometries for a given rim radius and bump height are compared. It is observed that at a given yield stress, donut-shaped bumps result in lower contact area and meniscus force compared to sombrero-shaped bumps.
Observations of the ion signatures of double merging and the formation of newly closed field lines

Observations from the Polar spacecraft, taken during a period of northward interplanetary magnetic field (IMF) show magnetosheath ions within the magnetosphere with velocity distributions resulting from multiple merging sites along the same field line. The observations from the TIDE instrument show two separate ion energy-time dispersions that are attributed to two widely separated (-20Re) merging sites. Estimates of the initial merging times show that they occurred nearly simultaneously (within 5 minutes.) Along with these populations, cold, ionospheric ions were observed counterstreaming along the field lines. The presence of such ions is evidence that these field lines are connected to the ionosphere on both ends. These results are consistent with the hypothesis that double merging can produce closed field lines populated by solar wind plasma. While the merging sites cannot be unambiguously located, the observations and analyses favor one site poleward of the northern cusp and a second site at low latitudes.
With Scripps library closure, university tries to minimize impact

The Scripps Institution of Oceanography (SIO) Library at the University of California, San Diego (UCSD) closed on 29 June, succumbing to budget cuts and a change in library usage that has included a shift toward electronic media and fewer people using the library's physical facilities. The SIO library's book and journal collections—which include more than 227,000 volumes and more than 700 print periodicals—will be transferred to UCSD's Geisel Library about 1 mile away; the Scripps archives and special collections will remain in their current location in the Eckart Building at SIO, according to a UCSD announcement. A note posted on the UCSD library Web site states, “Though Scripps Institution of Oceanography loses a library facility on campus, the UC San Diego Library remains committed to supporting Scripps faculty, staff and students, and continues to develop electronic and print collections to support the Institution's academic mission. Research and curriculum support services also continue to be available, by appointment.”
X-Ray Instrumentation in the LLL Laser-Fusion Program

The LLL Laser-Fusion Program includes an active experimental effort to measure the distributions in energy, space and time of pulses of soft X-rays (.2-10 keV) radiated by laser-induced plasmas. Requirements for high resolution in these measurements clearly preclude the use of conventional X-ray diagnostic techniques. We will describe the following as examples from our program of advanced X-ray instrument development. 1. Wavelength-dispersive spectrographs with fractional-electron volt resolution at several keV and imaging systems with 3 micron resolution over a 100 micron source. 2. Advanced solid state X-ray sensors that recover data from these instruments in a more expedient manner than photographic film. 3. Microcomputer-controlled stand-alone spectrograph data systems and minicomputer-based integrated systems that can deal with the large array of data generated by the high resolution instruments. 4. An electrostatically-deflected X-ray streak camera with moderate spectral and spatial resolution and a timing resolution of better than 15 ps.
Interaction of a nuclear location signal with isolated nuclear envelopes and identification of signal-binding proteins by photoaffinity labeling.

Abstract The nuclear envelope (NE) separates the two major compartments of eukaryotic cells, the nucleus and the cytoplasm. Recent studies suggest that the uptake of nuclear proteins into the nucleus is initiated by binding of nuclear location signals (NLSs) contained within these proteins to receptors in the NE, followed by translocation through the nuclear pore complex. To examine the binding step without interference from intranuclear events, we have used a system consisting of (i) purified rat liver NEs fixed onto glass slides and (ii) the prototype simian virus 40 large T antigen (SV40 T) NLS conjugated to nonnuclear carrier proteins, and we have visualized the receptor-ligand interaction by indirect immunofluorescence. In this system, incubation of isolated NEs with the wild-type SV40 T NLS conjugate with carrier proteins resulted in binding that was signal sequence-dependent, could be competitively blocked with excess conjugated and unconjugated wild-type peptide, did not require ATP, and was not affected by the transport-inhibiting lectin wheat germ agglutinin. In contrast, only minimal binding was observed with a mutant SV40 T NLS conjugate. These results are consistent with those obtained in other, more complex in vitro systems and suggest that binding of the SV40 T NLS is receptor-mediated. Binding is largely abolished by extraction of the NE with the nonionic detergent Triton X-100, suggesting that the receptor is soluble in detergent. We find in the Triton X-100 supernatant four major NLS-binding proteins with apparent molecular masses of 76, 67, 59, and 58 kDa by photoaffinity labeling with a highly specific crosslinker, azido-NLS. The reduced complexity of the system described here should be useful for the functional study of other potential NLSs for the identification and isolation of their binding sites and for the screening of antibodies raised against these binding sites.
On the reconstruction of polycrystalline microstructures from two-point correlation statistics

An exhaustive branching technique is introduced for reconstructing discrete microstructures from two-point statistic occurrences. It is shown that two-point statistics control microstructure, to the extent that exact replicas of discrete microstructures are produced when sufficient two-point statistic occurrences are matched. Efficiency comparisons between simulated-annealing methods and the exhaustive branching method are made on polycrystalline structures and some discussion on advancing the exhaustive branching method is given.
An autocrat's toolkit: adaptation and manipulation in ‘democratic’ Cameroon

Cameroon's President Paul Biya has weathered the transition from a single-party to a multi-party system, dramatically strengthening his control over the political apparatus in recent years. While many have noted the tendency of Africa's new ‘democrats’ to consolidate their authority by removing various constitutional restraints on their power, this paper argues that Paul Biya has adapted more subtly to the various opportunities provided by open political competition and international discourse on minority rights. Beyond the sadly predictable fraud in electoral counting, he has manipulated electoral boundaries to his party's advantage, while at the same time prohibited voting access to citizens who would likely vote for the opposition. In addition, he has acceded to constitutional changes to recognize minorities in compliance with international and domestic pressures, which is in reality yet another useful tool to marginalize the opposition.
Do vaginal birth after cesarean outcomes differ based on hospital setting

Objective The objective of the study was to test the null hypothesis that outcomes of vaginal birth after cesarean (VBAC) do not differ on the basis of the hospital setting. Study Design The study was a retrospective cohort study of women who were offered VBAC in 17 hospitals from 1996 to 2000. VBAC attempts occurring in hospitals with and without obstetrics-gynecology residency programs were compared, as were outcomes from university and community hospitals. Bivariate and multivariate logistic regression analyses assessed the association between hospital setting and VBAC outcomes. Results Of 25,065 women with 1 or more prior cesareans, the VBAC attempt rate was 56.1% at hospitals with obstetrics-gynecology residencies, 51.3% at hospitals without obstetrics-gynecology residencies, 61% at university hospitals, and 50.4% at community hospitals. The occurrence of failed VBAC, blood transfusion, or composite adverse outcome did not differ by hospital setting. There was a significant increase in the uterine rupture rate at community (1.2%) vs university hospitals (0.6%), but the absolute risk remained low. Conclusion The rate of VBAC-associated complications is low, independent of hospital setting.
IMPACT OF NIGHT-FLOAT ROTATION ON SLEEP, MOOD, AND ALERTNESS: THE RESIDENT'S PERCEPTION

Night-float rotations were designed to alleviate the workload of residents on night call and thereby improve patient safety. However, the impact of the night float on residents is yet to be surveyed. We assessed the impact of the night-float rotation on pediatric residents using an anonymous questionnaire that covered topics, based on recall, about sleep, mood, alertness, adjustment, and others. The study was conducted in a major tertiary pediatric teaching hospital in the United States. Participants were pediatric residents who had completed one or two night-float rotations and were in active training at our teaching hospital at the time of the study. Fifty-two of 60 eligible residents (87%) responded. Sleep duration during the night-float rotation was shorter than during day-shift work in 24 residents (46%), longer in 20 (38%), and unchanged in eight (15%). A higher proportion of residents took longer to fall asleep, had more difficulty falling asleep, had more sleep interruptions, and felt less rested upon awakening. Twenty-four residents (46%) felt that their bodies never adjusted to the night shift. Also, 22 residents (43%) felt moody or depressed in contrast to seven (14%) who felt depressed during the daytime rotation (p = 0.0001). Twenty-one residents (41%) felt they were slower in their thinking during the night float than daytime rotations. The results suggest that disturbances of sleep and mood and decreased alertness, typical of night shift, are present in the night-float rotation. Residency programs should monitor closely the impact of the night-float rotation on resident well being and patient safety. The impact of night-shift work should be considered in the design of night-float schedules, and teaching should be provided for residents to learn coping strategies for night-shift work.
Structures and dynamic motion of laminin-1 as observed by atomic force microscopy

Laminins are a family of multifunctional extracellular matrix glycoproteins that play important roles in the development and maintenance of tissue organization via their interactions with cells and other extracellular matrix proteins. To understand the structural basis of laminins' functions, we examined the motion of laminin-1 (Ln-1) in physiological buffers using atomic force microscopy. While many Ln-1 molecules assumed the expected cruciform structure, unexpected dynamic movements of the Ln-1 arms were observed in aqueous environments. These dynamic movements of the Ln-1 arms may contribute to the diversity of laminin functions.
Blood-nerve and blood-brain barrier permeabilities and nerve vascular space in Fischer-344 rats of different ages

Abstract The permeability-surface area product (PA) of [3H]- or [14C]sucrose at the blood-nerve barrier (BNB) of the sciatic nerve; and at the blood-brain barrier (BBB), were determined in Fischer-344 rats at 3, 11 and 31 months of age. PA was determined by using an in vivo i.v. bolus injection of radiotracer with two-time point graphic and quantitative autoradiographic methods. Vascular space and water content of the tibial nerve of these rats also were determined using quantitative morphometry and dry and wet weight ratios, respectively. There was no significant difference between mean PA(BNB) in any age group [(PA(BNB) at 3 months = 1.2 ± 0.1 (mean ± S.E.), at 11 months = 1.8 ± 0.3; and at 31 months = 1.4 ± 0.2 × 10−5 ml/s · g wet wt; n = 5–8 rats], nor any different in PA(BBB). The mean ratio (%) of surface area of endoneurial blood vessels/nerve cross-section of the tibial nerve also did not differ between any group [3 months: 16 ± 2 vessels; mean surface area ratios = 2.20 ± 0.10%, n = 5; 11 months: 22 ± 3 vessels and 2.48 ± 0.21%, n = 5; and at 31 months: 26 ± 1 vessels and 2.40 ± 0.23%, n = 4). The mean nerve water in rats at 31 months was 64.8 ± 1.1% wet wt and did not differ from that at 11 months (66.0 ± 0.6% wet wt) or at 3 months (65.1 ± 1.0% wet wt) (n = 5–8 nerves). Our results indicate that BBB and BNB integrities are not altered in senescent Fischer-344 rats.
Structure, dynamics and hydrogen bonding of acetonitrile in nanoscale silica pores

Molecular dynamics simulations are used to investigate the behaviour of liquid acetonitrile confined within nm diameter silica pores. Different approaches for characterising the liquid structure i...
Effects of methyl methacrylate monomer vapors on respiration and circulation in unanesthetized rats

Abstract A study was conducted in which two groups of female rats were exposed to vaporized MMA-m for a period of 20 minutes daily for 21 and 42 days, respectively. Systolic blood pressure, heart rate, respiration, and ECG were monitored for 5 minutes prior to MMA-m exposure and then during a 20-minute exposure to MMA-m. On the twenty-first and forty-second day, respectively, the aforementioned vectors were monitored again. During the first exposure 63% of the experimental animals displayed marked changes in respiration ranging from a modified Cheyne-Stokes type to periods of very shallow breathing followed by deep breathing. Thirty-eight percent showed ECG changes ranging from premature ventricular contractions and altered QRS complexes to markedly depressed T waves. Continued exposure resulted in an initial decrease followed by an increased systolic blood pressure with an increased respiratory and heart rate. At the final testing period all animals showed abnormal respiratory patterns and ECG changes and demonstrated a heart block pattern. In all animals systolic blood pressure increased the longer they were exposed to MMA-m.
Metabolic biotinylation of recombinant antibody by biotin ligase retained in the endoplasmic reticulum

Due to its strength and specificity, the interaction between avidin and biotin has been used in a variety of scientific and medical applications ranging from immunohistochemistry to drug targeting. The present study describes two methods for biotinylation of proteins secreted from eukaryotic cells using the Escherichia coli biotin protein ligase. In one system the biotin ligase was co-secreted from the cells along with substrate protein enabling extracellular biotinylation of the tagged protein. In the other system, biotin ligase was engineered to be retained in the endoplasmic reticulum (ER) and metabolically biotinylates the secretory protein as it passes through the ER. An engineered antibody fragment, a diabody with specificity for carcinoembryonic antigen (CEA) was fused to the biotin acceptor domain (123 amino acid) of Propionibacterium shermanii. Coexpression of the fusion protein with ER retained biotin ligase showed higher biotinylation efficiency than biotinylation by co-secreted ligase. Biotinylation of the anti-CEA diabody tagged with a short (15 amino acid, Biotin Avitag) biotin acceptor peptide was also successful. Utilization of ER retained biotin ligase for biotinylation of protein is an attractive alternative for efficiently producing uniformly biotinylated recombinant proteins for a variety of avidin-biotin technologies.
Evolution of P3 morphology in Australopithecus afarensis

The Australopithecus afarensis dental sample exhibits a wide range of variation, which is most notable in the morphology of the lower third premolar (P3). P3 morphology in the A. afarensis sample ranges from the primitive sectorial extreme in AL 128-23 to the derived, bicuspid (molarized) extreme in AL 333w-1. In this paper, the degree and patterning of variation of the 20 known A. afarensis P3s are examined and the evolutionary implications are discussed. Initially, a series of dental and mandibular metric criteria are evaluated to determine whether this sample may be analyzed as a single species. From the metrics, it is clear that the single species hypothesis cannot be rejected. Next, a series of morphological criteria is devised to measure P3 molarization. Taken as a whole, the A. afarensis P3 sample displays more variation than a sample of modern hominoids (Pan troglodytes) and shows a slight trend toward increased molarization through time. When separated by sex, the A. afarensis sample still displays greater variation than the chimpanzee sample; however, only the male A. afarensis specimens show a trend toward increased molarization. Additionally, the male A. afarensis P3s are more molarized than the female, a pattern that is seen as well (though less markedly) in the chimpanzee sample. The trend toward increased molarization over time indicates selection for grinding in A. afarensis. The sexual differences parallel those seen in the postcrania (cf. Stern and Susman: Am. J. Phys. Anthropol. 60:279-318, 1983), as the females tend to retain the primitive condition, while the males display the derived morphology. Consequently, a model of sexual differences in niche exploitation, with the females exploiting a more arboreal environment, would seem to be supported by both the dental and postcranial evidence.
High-Performance Computational Chemistry: Hartree-Fock Electronic Structure Calculations on Massively Parallel Processors

The parallel performance of the NWChem version 1.2a parallel direct-SCF code has been characterized on five massively parallel supercomputers (IBM SP, Kendall Square KSR-2, CRAY T3D and T3E, and Intel Touchstone DELTA) using single-point energy calculations on seven molecules of varying size (up to 389 atoms) and composition (first-row atoms, halogens, and transition metals). The authors compare the performance using both replicated-data and distributed-data algorithms and the original McMurchie-Davidson and recently incorporated TEXAS integrals packages.
The necessary connection between internal and external state legitimacy: concerns regarding intervention

It has been traditional in political philosophy to take internal and external state legitimacy as resting on distinct criteria. However, this is a view that is currently being challenged. Assuming that internal and external legitimacy rely on the same criterion, a possible worry that arises is that an unacceptable amount of intervention will necessarily become justifiable. I argue that such worries are not significant and that they do not rule out this alternative to the traditional view.
The role of visual experience in aligning sensory and motor maps in the optic tectum of the barn owl

Abstract The optic tectum contains maps of visual and auditory space that are aligned with a map of spatially directed movement. The map of visual space derives from a stereotypic, pointto-point projection of the retina; however, the maps of auditory space and of movement derive from neural computation and depend on factors that vary across individuals. What brings these maps into mutual registration? In barn owls raised without vision, tectal maps of auditory space and of head movement develop abnormally and are misaligned both with each other and with the map of visual space. Thus, early visual experience enables sensorimotor registration.
Expression of Platelet-Derived Growth Factor (PDGF) in pulmonary artery (PA) smooth muscle (SM) during normal ovine development and neonatal pulmonary hypertension (PH) † 90

Expression of Platelet-Derived Growth Factor (PDGF) in pulmonary artery (PA) smooth muscle (SM) during normal ovine development and neonatal pulmonary hypertension (PH) † 90
Criteria for Selective Utilization of the Intensive Care Unit following Carotid Endarterectomy

= 62, p < 0.05), emergent CEA (n= 2, p= 0.01), and need for postoperative anticoagulation (n= 2, p= 0.01). Only 56 (15%) of patients had indications for ICU admission, 57 (16%) would have been admitted to an EKG-monitored nursing unit, and 252 (69%) would have been admitted to a standard nursing unit. Immediate admission to the ICU after CEA is indicated for patients undergoing emergent CEA, those requiring anticoagulation postoperatively, those with intraoperative stroke or major cardiac complication, and possibly those with chronic renal failure. All other patients should be admitted to the RR. Patients experiencing stroke, major cardiac events, significant wound hemorrhage, or reintubation in the RR, and those requiring vasoactive medication more than 3 hours after surgery should be transferred to the ICU. Patients with indications of cardiac disease within 6 months prior to CEA but no indications for ICU admission may be discharged from the RR to an EKG monitored unit. All others may be discharged to a standard nursing unit.
Intraoperative diastolic dysfunction as a risk factor for hemodynamic instability

Background: Diastolic function can be evaluated intraoperatively using transesoptiageal echocardiography. Aim: To study if intraoperative diastolic dysfunction is associated to a greater number of hemodynamic events during surgery and during the postoperative period. Material and methods: Patients with indication of intraoperative transesophageal echocardiography due to cardiovascular diseases were included in the study. Diastolic function was assessed measuring transmitral intraventricular filling delay and pulmonary vein now. Patients were divided, according to diastolic dysfunction, in those with derangements in relaxation, pseudonormalization and restrictive patterns. Hypertension, hypotension, ST segment depression, alterations in myocardial contractility, pulmonary congestion and postoperative oliguria were recorded. Results: Fifty eight patients aged 68± 12 years (39 males), were studied. Forty four had diastolic dysfunction. Intraoperative hypotension occurred in 82% of patients with diastolic dysfunction and 16% of patients without it. Likewise, hypotension and oliguria during the postoperative period were more common in patients with diastolic dysfunction. Conclusions: In this group of patients with cardiovascular disease, intraoperative diastolic dysfunction is a risk factor for hemodynamic instability
Cleavage of Pro-X and Glu-X Bonds Catalyzed by the Branched Chain Amino Acid Preferring Activity of the Bovine Pituitary Multicatalytic Proteinase Complex (20S Proteasome)

Abstract The multicatalytic proteinase complex or 20S proteasome is involved in the extralysosomal degradation of both long- and short-lived proteins. The eukaryotic enzyme is composed of 14 nonidentical subunits arranged as a complex dimer of the composition (α7β7)2. Recent studies identify N-terminal threonines present on some β-subunits as the active-site residues. It has been proposed that the molecule contains three or four proteolytically active subunits [Seemulleret al., Science268, 579–582 (1995)]. Studies with synthetic substrates, activators, and inhibitors, however, have identified at least five distinct catalytic activities. To further characterize the specificity of the previously defined “peptidyl glutamyl peptide bond hydrolyzing activity,”N-benzyloxycarbonyl-Leucyl-Leucyl-Glutamal was synthesized as a potential inhibitor. Surprisingly, this aldehyde most potently inhibited the “branched chain amino acid preferring activity” (BrAAP). To further explore BrAAP specificity, novel substrates containing internal prolyl and glutamyl residues were synthesized. Their use established that the BrAAP activity catalyzed both a postproline and a postglutamate cleavage and therefore has a broader specificity than previously recognized. These results help explain earlier observations on treatment of the multicatalytic proteinase complex with 3,4-dichloroisocoumarin. This reagent activates both the BrAAP activity and the degradation of β-casein and inhibits the other catalytic activities.
Effect of Chemical Systemic Acquired Resistance Elicitors on Avenanthramide Biosynthesis in Oat (Avena sativa)

Oats produce a group of phenolic antioxidants termed avenanthramides. These metabolites are, among food crops, unique to oats and have shown, in experimental systems, certain desirable nutritional characteristics such as inhibiting atherosclerotic plaque formation and reducing inflammation. Avenanthramides occur in both the leaves and grain of oat. In the leaves they are expressed as phytoalexins in response to crown rust (Puccina coronata) infection. The experiments reported here demonstrate that avenanthramide levels in vegetative tissue can be enhanced by treatment with benzothiadiazole (BTH), an agrochemical formulated to elicit systemic acquired resistance (SAR). The response to BTH was dramatically stronger than those produced with salicylic acid treatment. The roots of BTH treated plants also showed a smaller but distinct increase in avenanthramides. The dynamics of the root avenanthramide increase was substantially slower than that observed in the leaves, suggesting that avenanthramides might be transported from the leaves.
Skill versus Chance Tasks Comparison of Locus of Control, Defensive Externality, and Persistence

The value placed on success in achievement situations by internals and congruent (CE) and defensive (DE) externals was investigated in tasks defined as either skill-or chance-determined. Internals and DEs persisted longer on the skill task than CDs, while both external groups worked longer on the chance task than internals. Across task conditions, internaLs and DEs persisted longer in the skill than chance task, while CEs did not dffer. These results support the utility of the CE-DE distinction, and suggest that DEs behave similarly to internals in skill-based achievement situations, while externality for CEs is more representative of a veridical set of external control beliefs.
Age-associated increase in ferritin content of male rat liver : implication for diquat-mediated oxidative injury

Our previous studies in rat hepatocytes demonstrated an age-dependent increase in sensitivity to diquat-induced cytotoxicity, possibly as a result of increased iron availability. The present study was conducted to determine whether quantitative or qualitative changes in hepatic ferritin occur as a consequence of aging and whether diquat-mediated oxidation is intensified by elevated ferritin concentrations. Hepatic ferritins were isolated from male Fischer 344 rats ages 5, 15, and 25 months. Age-associated increases were observed in amounts of ferritin protein and ferritin iron per gram of liver, but there were no differences in proportions of H to L subunits or in rates of diquat-mediated iron release. The consequences of a threefold increase in ferritin content for diquat-mediated lipid peroxidation and protein carbonyl formation were examined in microsomal incubation systems. The addition of isolated rat liver ferritin augmented diquat-mediated oxidative damage in a time- and concentration-dependent manner, and the inclusion of deferoxamine completely inhibited the stimulation by ferritin. The results indicate that availability of ferritin iron is an important determinant of diquat-mediated oxidative injury and support the hypothesis that elevated hepatic ferritin content is responsible, at least in part, for the age-associated enhancement of diquat-induced toxicity.
Breaking criteria and energy losses for three‐dimensional wave breaking

[1] Laboratory experiments were used to explore the influence of spatial focusing and diffraction on the evolution of unsteady, three-dimensional, deep water wave packets with a constant-steepness spectrum. The wave packets were generated by 13 independently programmed paddles and evolved to breaking near the midpoint of a 4 m × 11 m test section. Detailed measurements of surface displacements were made across the entire test section and were used to examine energy losses and breaking criteria. Three forms of breaking criteria were considered: (1) geometric criteria based on local and global wave steepness, (2) a kinematic criterion based on particle and phase velocities, and (3) a dynamic criterion based on higher harmonic energy evolution. The results indicate that directionality of the waves can either increase (focusing waves) or decrease (diffracting waves) the geometric breaking criterion as well as breaking severity. In contrast, the directionality of waves had little effect on the kinematic criterion. At breaking, the ratio of local particle velocity and phase velocity was shown to be larger than unity for both focusing and diffracting waves. Indeed, the robustness and simplicity of the kinematic criterion make it an excellent choice for field application. Finally, the directionality of waves did not alter the up-frequency energy transfer associated with wave steepening. The three-dimensional, spatially focusing and diffracting wave packets lost 34% and 18% of their energy, respectively, as a result of plunging breakers and lost 12% and 9%, respectively, as a result of spilling breakers. Comparable two-dimensional breakers with the same spectral shape lost 16% for plunging and 12% for spilling.
Combining Cases and Computer Simulations in Strategic Management Courses

In this study, the author compared the effectiveness of two different strategic management course designs: one centered on case discussions and the other combining a computer-based simulation with some cases. In addition to evaluation of the research literature, the study involved experiments with six course sections composed of 130 students, Both course designs produced statistically equivalent learning outcomes; there were no significant differences between the two course designs in any of the nine outcome measures, including objective measures and student perceptions.
Overwintering Populations of Scolytus ventralis (Coleoptera: Scolytidae) Reduced by Extreme Cold Temperatures

On December 30, 1968, the weather station at the University of Idaho, Moscow, recorded a low temperature of − 42°F. Examination of the weather records back to 1930 showed that − 42°F was the coldest temperature experienced over this time period, although the mercury dropped below − 20°F in 5 of these 38 years and below −30°F in 1 year.
Examining Sexual Health Differences between Lesbian, Gay, Bisexual, and Heterosexual Adults: The Role of Sociodemographics, Sexual Behavior Characteristics, and Minority Stress

Many studies focus on the differences in mental health between lesbian, gay, bisexual (LGB), and heterosexual individuals. Less attention has been paid to the differences in various aspects of sexual health and the potential explanations for these differences. Data from a Dutch population study on sexual health (aged 19-70 years; N = 4,333) were used to examine the potential differences in sexual satisfaction, sexual victimization, sexual dysfunction, and sexual health care need. At the same time, this study examined whether the differences could be attributed to differences in general factors influencing sexual health (sociodemographic variables and sexual behavior characteristics) or to LGB-specific factors (minority stress). The results showed that bisexual women and bi- and homosexual men had more often experienced sexual coercion and reported a higher need for sexual health care than their heterosexual counterparts. Both general determinants (e.g., a higher number of sexual partners or being single) and LGB-specific factors (e.g., internalized homonegativity or negative social reactions related to sexual orientation) were associated with different aspects of sexual health. Interventions aimed at improving the sexual health of LGB individuals should focus on general risk factors, as well as on LGB-specific stressors. Methodological limitations of the study and implications for further research are discussed.
Commitment to Work and Wages Earnings Differences of Black and White Women

Studies of earnings differences between black and white women consistently indicate that the major source of black women's lower annual earnings is their smaller human capital accumulation, in the form of schooling and their less prestigious occupations. However, this research also indicates that black women partially compensatefor these deficiencies by achieving a higher rate of wage return on their human capital and occupational status. In this study earnings models are examined for black and white women 30 to 44 years old. The results indicate that experience does influence differ ential wage returns to schooling and occupational status by enhancing the value of these characteristics for women with high education, greater prestige occupations, and extensive work experience. These analyses also provide support for an occupational decision-making explanation which contributes to observed differentials in wage returns to schooling.
Applying social science research to film ratings: A shift from offensiveness to harmful effects

The Motion Picture Association of America (MPAA) provides ratings for the majority of commercially released films. The MPAA system is based largely on estimates of what types of film content may be offensive to most parents. We identify four assumptions that underlie the current rating system and show how these assumptions are inconsistent with social science research regarding the impact of media portrayals on young viewers. Finally, we offer an alternative scheme based on what is harmful to children rather than what is offensive to parents.
Midfollicular anticardiolipin and antiphosphatidylserine antibody titers do not correlate with in vitro fertilization outcome

Abstract Objective: To determine the prevalence of anticardiolipin and antiphophatidylserine antibodies in an IVF population and to correlate their presence and specific isotype with IVF cycle outcome. Design: Retrospective clinical study using stored midfollicular sera for determination of antibody status. Setting: University hospital infertility clinic. Patient(s): Women who underwent IVF treatment in 1991. Intervention(s): Midfollicular sera were used to assess antibody status during the time of stimulation for IVF. Main Outcome Measure(s): Anticardiolipin and antiphosphatidylserine antibody titers and biochemical or sonographic documentation of IVF cycle outcome. Result(s): The overall prevalence of anticardiolipin and antiphosphatidylserine antibodies in IVF patients was 7.0% and 11.2%, respectively. There was no statistically significant difference in the prevalence of these antibodies in the groups of patients with a biochemical pregnancy (0 for anticardiolipin and 2.8% for antiphosphatidylserine), spontaneous miscarriage (11.4% for anticardiolipin and 20% for antiphosphatidylserine), ongoing pregnancy (7.3% for anticardiolipin and 11.6% for antiphosphatidylserine), and patients who failed to conceive (7.2% for anticardiolipin and 10.8% for antiphosphatidylserine). There was no correlation between outcome and the antibody isotype expressed. Conclusion(s): Anticardiolipin and antiphosphatidylserine antibodies are poorly predictive of the IVF cycle outcome. Routine testing of IVF patients for the presence of these antibodies is of limited clinical utility.
On the design of neural‐fuzzy control system

This article presents a neural–network-based fuzzy logic control (NN–FLC) system. The NN–FLC model has the learning capabilities for constructing membership functions and extracting fuzzy rules from training examples. Both unsupervised and supervised training algorithms are used to find the membership functions of the FLC. Competitive learning algorithms are employed to evaluate fuzzy logic rules. Matlab programs using both neural and fuzzy toolboxes are developed to implement the NN–FLC model. Computer simulations of the inverted pendulum controlled by NN–FLC system were conducted to illustrate the self-learning ability of the network. © 1998 John Wiley & Sons, Inc.13: 11–26, 1998
Kernel Coefficient Ideals in Noetherian Rings

Abstract A new ideal I *, the kernel coefficient ideal of a nonprincipal ideal I , is introduced in a commutative Noetherian ring R . Various properties of this ideal and its relations with many other standard concepts are studied. I * is also examined in terms of a sequence of subideals I n and the relation type of I when R is a local ring. Several characterizations of I * are given in terms of the kernels of certain ring homomorphisms, and then it is shown that this new ideal has many nice applications, especially in the study of asymptotic prime divisors.
X‐ray fluorescence analysis of catalytic converters using single‐element standards and theoretical corrections for interelement effects

An X-ray fluorescence technique for the quantitative analysis of phosphorus, sulfur, chromium, iron, nickel, copper, zinc, zirconium, ruthenium, rhodium, palladium, barium, lanthanum, cerium, iridium, platinum and lead on fresh and used catalytic converters is described. The method used is to correct the measured X-ray intensities of each element using theoretically calculated interelement absorption and enhancement effects so that they may be compared to X-ray intensities measured on single element standards. The elemental concentrations are obtained from intensity calibration curves derived from the known compositions of the standards.
Separation of metabolically radiolabeled O-methylmannitols and O-methylfucitol by reverse-phase high-performance liquid chromatography: Applications to animal cell oligosaccharide structural analysis

Abstract Reverse-phase high-performance liquid chromatography was utilized to separate efficiently and rapidly a standard mixture of various radiolabeled O -methylated mannitols and O -methylfucitol commonly encountered when vertebrate asparagine-linked oligosaccharides are subjected to permethylation, hydrolysis, and reduction with NaBH 4 . The following reduced, radioactive O -methylhexitols were resolved: 2,4-, 3,4-, and 3,6-di- O -methylmannitols; 3,4,6-tri- O -methylmannitol, 2,3,4-tri- O -methylfucitol, and 2,3,4,6-tetra- O -methylmannitol. To demonstrate the utility of this separation method in the analysis of metabolically radiolabeled asparagine-linked oligosaccharides, mouse lymphoma BW 5147 cells were metabolically radio-labeled with [2- 3 H]mannose and their glycopeptides prepared by Pronase digestion and fractionated by serial chromatography on immobilized lectins. Each fraction was subjected to methylation and hydrolysis, the released monosaccharides were reduced, and the radioactive O -methylhexitols were separated by reverse-phase HPLC. The relative amounts of the O -methylhexitols in each glycopeptide fraction analyzed were similar to those values determined by a combination of other separation systems.
Alternation behavior of children in a cross-maze

Seventy-five children of preschool age were observed in a cross-maze. The frequency of alternation increased with age for the Ss who started both trials from the same start position but did not change across age for the Ss who started the two trials from opposite start stems. Running time decreased with increasing age under both conditions.