cssi/SciSciGPT-SciSciNet huggingface dataset:
A comparison of the clinical utility of several published formulae for estimated osmolality of canine serum.

Objective To determine the normal osmole gap for 18 previously published formulae used to estimate serum osmolality in dogs. Design Prospective study. Setting University veterinary medical teaching hospital. Animals Two hundred and fifty client-owned dogs. Interventions None. Measurements and Main Results Serum samples were saved and frozen at −80°C after routine biochemical analysis as ordered by attending clinicians. An Advanced Micro Osmometer 3300 was used to measure serum osmolality. Eighteen distinct formulae previously reported in the medical literature were used to calculate the osmolality from the biochemical analysis results. The calculated osmolality was then subtracted from the measured osmolality to determine the osmole gap. Osmole gaps for azotemic and hyperglycemic dogs were compared to those of dogs without azotemia or hyperglycemia using each formula. The median measured osmolality for all dogs in the study was 302 mOsm/kg (interquartile range 297–307). The osmole gaps varied widely depending on the formula used to calculate osmolality and the presence or absence of hyperglycemia or azotemia. Eleven formulae led to calculated osmolality and osmole gaps that were not statistically different when hyperglycemia or azotemia was present. Four out of these 11 formulae resulted in osmole gaps near zero. Conclusions and Clinical Relevance Multiple formulae reported to calculate serum osmolality can be used in the clinical setting, but they result in significantly different normal osmole gaps. Clinicians should be aware of the specific reference interval for the formula being used. The authors recommend the formula 2(Na+) + [glucose/18] + [BUN/2.8] because it is easy to use and is reliable even when hyperglycemia or azotemia are present.
Facilitating Commenting and Requesting Skills in 3-Year-Old Children With Disabilities:

The current study evaluated the commenting behaviors and verbal and non-verbal requests of children with disabilities (e.g., developmental delays, specific language impairment) who participated in ...
Ultrasonic Imaging of the Electroacoustic Effect in Macromolecular Gels

The electroacoustic effect occurs in electrolytes and colloidal suspensions. It describes the phenomenon in which a voltage applied to the sample produces an acoustic signal or vice versa. The basic mechanism is that charged particles in the sample have various mobilities due to different masses and viscosities. Under an external voltage they respond differently to the electrical force. This results in an overall acoustic vibration. The electroacoustic effect has been the basis for many measurement tools of solutions and other materials. In this note a method to image macromolecular gel samples using the electroacoustic effect at ultrasound frequencies is presented. Radio-frequency electrical excitation produces ultrasonic signal due to spatial changes in the electroacoustic sonic amplitude of the sample, which is used to construct an image similar to ultrasonography. This method is demonstrated in agar gel and eggwhite protein phantoms. The image contrast mechanism is also discussed.
Enzymatic behaviour of the product of coenzyme A-norepinephrine reaction.

REACTION of the sulphydryl group of coenzyme A in vitro with oxidation products of epinephrine and nor-epinephrine has been demonstrated by chemical measurement of the residual —SH groups1. The coenzyme A–catecholamine compounds may well represent an important stage in intermediary metabolism, since their breakdown may lead to regeneration of coenzyme A and formation of physiologically active catecholamine derivatives. Furthermore, if coenzyme A is inactivated by these reactions, an explanation may be at hand for some of the physiological effects of the catechol amines. The work reported here evaluates the reactivity and stability of the coenzyme A–catecholamine derivatives in the light of their enzymatic activity in vitro.
Preparation and in vitro evaluation of bioactive glass (13–93) scaffolds with oriented microstructures for repair and regeneration of load-bearing bones

Bioactive glass (13-93) scaffolds with oriented microstructures, referred to as 'columnar' and 'lamellar', were prepared by unidirectional freezing of suspensions, and evaluated in vitro for potential use in the repair and regeneration of load-bearing bones in vivo. Both groups of scaffolds showed an 'elastic-plastic' mechanical response in compression, large strain for failure (>20%), and strain rate sensitivity, but the columnar scaffolds had the additional advantages of higher strength and larger pore width. At the equivalent porosity (55-60%) and deformation rate (0.5 mm/min), the columnar scaffolds had a compressive strength of 25 +/- 3 MPa, elastic modulus of 1.2 GPa, and pore width of 90-110 microm, compared to values of 10 +/- 2 MPa, 0.4 GPa, and 20-30 microm, respectively, for the lamellar scaffolds. Cellular response to the scaffolds was evaluated using murine MLO-A5 cells, an osteogenic cell line. While the cellular response to both groups of scaffolds was better than control wells, the columnar scaffolds with the larger pore width provided the most favorable substrate for cell proliferation and function. These results indicate that 13-93 bioactive glass scaffolds with the columnar microstructure could be used for the repair and regeneration of load-bearing bones in vivo.
Pneumoperitoneum after concomitant resection of the right middle and lower lobes (bilobectomy).

Abstract Background . Removal of the right middle and lower lobes often leaves a pleural space problem that can cause prolonged air leaks. Methods . A single surgeon prospectively randomized 16 patients who underwent bilobectomy. Eight patients had 1200 mL of air injected under the right hemidiaphragm after bilobectomy and 8 did not. The air was injected through a small transdiaphragmatic opening made in the right hemidiaphragm at the time of pulmonary resection. Results . The age of the patients, preoperative pulmonary function, preoperative comorbidities, indications for surgery, and final pathology were not significantly different between the two groups. On postoperative day #1, a pneumothorax was present in 1 patient (13%) in the pneumoperitoneum group ( P group) and in 4 patients (50%) in the nonpneumoperitoneum group (N- P group). On postoperative day 1, an air leak was present in 1 patient (13%) in the P group and 5 patients (63%) in the N- P group ( p P group had an air leak; however, a leak was present in 4 patients (50%) in the N- P group ( p P group was 4 days (range, 3 to 6 days), compared with 6 days (range, 4 to 8 days) in the N- P group ( p P group were sent home with a Heimlich valve. There was no operative mortality and no complications from the pneumoperitoneum. Conclusions . We conclude that pneumoperitoneum after bilobectomy is safe and easy to do. It decreases the incidence of air leaks and of pneumothoraces and shortens hospital stay without increasing morbidity. We recommend pneumoperitoneum after bilobectomy at the time of thoracotomy, especially if there are residual small air leaks that cannot be sealed before chest closure.
Transactions of persons-in-environments: Some critical transitions

The organismic-developmental approach to the analysis of critical transactions of persons-in-environments is described in terms of its basic assumptions and a number of empirical studies on critical transitions, including relocation of a psychiatric therapeutic community, transition from work to retirement, and from high school to college.
Numerical simulation of the smooth quantum hydrodynamic model for semiconductor devices

Abstract An extension of the classical hydrodynamic model for semiconductor devices to include quantum transport effects is reviewed. This “smooth” quantum hydrodynamic (QHD) model is derived specifically to handle in a mathematically rigorous way the discontinuities in the classical potential energy which occur at heterojunction barriers in quantum semiconductor devices. A conservative upwind discretization of the one-dimensional (1D) steady-state smooth QHD equations is outlined. Smooth QHD model simulations of the resonant tunneling diode are presented which exhibit enhanced negative differential resistance when compared with simulations using the original O(ℏ 2 ) QHD model.
Toward a dynamic real-time intraoperative permanent prostate brachytherapy methodology.

Abstract Purpose To evaluate dosimetry and source location relative to CT-based dosimetry when performing real-time dynamic permanent prostate brachytherapy (PPB) with inverse treatment planning. Methods and materials A treatment algorithm for dynamic PPB was developed using inverse treatment planning. The technique utilizes real-time transrectal ultrasound prostate imaging connected to the treatment planning software. The implementation of the plan with the Mick interstitial gun is monitored with up-to-date dosimetry assessments based on the registration of each seed when placed. Real-time dose assessment is monitored and adjustments can be made during the case, if necessary. A final OR dosimetric (OR-D) assessment based on the registered seed locations is performed. Postoperative CT scans obtained at 3 weeks are used for traditional dosimetry analysis (CT-D). A matrix algorithm was developed to match the seed locations from the ultrasound registration to that of the CT-scan parameters. Results Twenty-six consecutive patients with clinically localized prostate cancer underwent PPB using the algorithm designed for dynamic real-time planning. The OR-D identified a mean D90 of 109% (range 100–118%) whereas the mean CT-D D90 at 3 weeks was 105% (range 89–122%) (p = 0.894). Analysis of the OR-D V100 and V150 relative to the 3-week CT-dose V100 and V150 were also insignificant (p = 0.112 and 0.167, respectively). Assessment of seed locations relative to the intraoperative ultrasound and postimplant CT identified a mean root-mean-square error of 4.6 mm (0–21 mm). The mean error for the x, y, and z coordinates were 2.01 mm, 2.24 mm, and 2.85 mm, respectively. Conclusions This study reports the preliminary results of a new treatment algorithm for PPB that incorporates intraoperative inverse planning with dynamic dosimetry assessment during the case. Correlation was seen between the completed intraoperative, postimplant plan and the CT based plan at 3 weeks. Seed to seed deviations between the OR-D matched well with the CT-D. Additional study is necessary to assess whether this approach can assist in improving implant dosimetry and whether it appropriately documents the OR-dose without the need for postimplant dosimetry.
Steps to demarcate the effects of chromophore aggregation and planarization in poly(phenyleneethynylene)s. 2. The photophysics of 1,4-diethynyl-2-fluorobenzene in solution and in crystals.

Crystals of 1,4-bis(2-hydroxy-2-methyl-3-butynyl)-2-fluorobenzene 4 have a rich packing structure with four distinct molecules in the unit cell. A complex hydrogen bonding network results in the formation of cofacial trimers, cofacial dimers, and monomers within the same unit cell. Given a remarkable opportunity to investigate the effect of aggregation on the photophysics of 1,4-diethynylbenzenes, we analyzed the absorption, diffuse reflectance, and emission spectra of compound 4 in solutions and in crystals. Diffuse reflectance and fluorescence excitation revealed a red-shifted absorption that is absent in dilute solution but becomes observable at high concentrations and low temperatures. The fluorescence emission in the solid state is dual with components assigned to monomers and aggregates. The excitation and emission assigned to the monomer are nearly identical in crystals and dilute solutions. The absorption and emission bands assigned to aggregates are broad and red-shifted by 60−80 nm. As expected ...
Depletion interaction in a quasi-two-dimensional colloid assembly

We address several aspects of the character of the depletion interaction in a quasi-two-dimensional (Q2D) colloid system. First, we consider how, given information concerning the pair and triplet correlation functions, the depletion interaction can be efficiently and accurately determined. For this purpose we introduce a method based on the Born-Green equation using the assumption that for the Q2D binary mixtures of interest to us the depletion interaction is accurately represented as a sum of pair potentials. We then verify, by direct calculation, that three-particle contributions to the depletion interaction are negligibly small in the region of thermodynamic state space of interest to us. Second, we develop a representation of the dependence of the depletion interaction in a Q2D colloid system on the thickness of the confining parallel plates. Third, we report the results of extensive simulations of Q2D binary hard-sphere mixtures for a range of cell thickness, large and small particle number densities, and a ratio of sphere diameters $q=0.3$.
Predicting vapor pressures using neural networks

Abstract Calculating surface vapor pressures of volatile inorganic components, nitric acid, hydrochloric acid and ammonia, is essential for modeling condensation and evaporation processes occurring in atmospheric aerosols. The vapor pressure of these compounds depends on temperature, relative humidity, phase state, and particle composition, and their calculation consumes an enormous amount of computer time in Eulerian photochemical/aerosol models. Here we use a thermodynamic model to generate a large set of vapor pressure data as a function of aerosol composition, relative humidity, and temperature. These data are then used as a training set for neural networks. Once the networks memorize the data, interpolation of vapor pressures for intermediate compositions, temperatures and relative humidities is automatic. The neural network models are able to reproduce the values predicted by the thermodynamic models accurately and are 4–1200 times faster depending on atmospheric conditions and the assumptions employed in the thermodynamic calculations.
Reading and Writing Performance

Criteria for evaluating experimental ethnographic texts are reviewed. Subversive, resistance narratives are foregrounded. While the focus is primarily on North American work, scholarship by non-Ame...
CONTRIBUTIONS OF A NONPROFIT EDUCATIONAL MEASUREMENT ORGANIZATION TO EDUCATION POLICY RESEARCH

As part of its mission, Educational Testing Service (ETS) has conducted education policy research focused on promoting equal opportunity for all individuals from early childhood through adulthood. This report provides a sampler of this extensive work in three areas chosen to represent major historical foci: • Analyzing, evaluating, and informing public policy in educational governance, including school finance; teacher policy; and federal, state, and local education policy; • Examining differential access to educational opportunity in three areas of longstanding interest to ETS: the gender gap, advanced placement programs, and graduate education; and • Reporting on the educational outcomes of the U.S. population and describing the contexts for these outcomes and for the gaps in outcomes that exist among segments of the population.
Some new methods of RF control

This presentation will focus on several recent developments at Los Alamos in the area of RF control for accelerators. Included in the discussion will be in-phase/quadrature (I/Q) field control, the application of six-port reflectometers for cavity instrumentation and resonance control, a technique for phase stabilization of critical RF cables, an application of state-variable feedback for field control, and the direct integration of RF and computer-interface hardware using the VXIbus standard. 25 refs., 8 figs.
Multiple scales of diamond mining in Akwatia, Ghana: addressing environmental and human development impact

Ghana is the second largest producer of gold in sub-Saharan Africa, and has experienced a significant increase in national mining production over the last two decades. Between 1983 and 1998, the mining industry brought approximately US $4 billion in foreign direct investment to Ghana. While large-scale gold mining has seen a significant increase, artisanal gold and diamond mining product have grown exponentially. While much research has been conducted on gold mining in Ghana, there is relatively little research on the environmental and human development consequences of diamond mining in the country. Unlike other West African countries such as Sierra Leonne and Liberia, small-scale diamond mining in Ghana has not been linked to conflict but its role in development has also been relatively modest. This paper examines large and small-scale mining in Ghana's largest diamond mining town, Akwatia, and their relative impact on environmental degradation, health, and the livelihood of artisanal miners. We conclude that while an increase in artisanal diamond mining has been a means of employement and income-generation for small-scale miners, there are some human development challenges, related to environmental burden from land degradation and health. GCD is an ailing mining company in Ghana, in desperate need of an injection of capital to keep the mine alive, but botched bidding has slowed the process of de-regulating the company. We also conclude that the de-regulation of GCD may lead to a relatively reduced environmental burden in Akwatia and more revenue for the GCD to invest in the human development needs of communities in the town.
Acquired immunodeficiency syndrome (AIDS): a commentary on the international aspects of the disease

By the beginning of 1987 there were 1100 heterosexual cases of AIDS in the US and by 1991 an estimated 1/4 million US citizens will have AIDS or will have already died from it. The situation in the 3rd World is even more grim. In parts of Africa the annual incidence of HIV infection is approaching 1%. Up to 12% of pregnant women in urban hospitals in Zaire carry the virus and 25-88% of the prostitutes in some of the large cities in sub-Sahara Africa have the disease. Already 5-10 million people around the world may be carrying HIV. Like the influenza virus HIV can change its protein coat rapidly. The victim can appear perfectly healthy and still spread the disease. In countries with low maternal mortality it could become the most common cause of maternal death. If people are to adopt safe sex practices they must be convinced that they are at risk that a lethal disease can be asymptomatic but ineffective for many years. They must know that safety practices--including the use of condoms and perhaps especially spermicidally lubricated condoms--offer worthwhile protection. If any link in this chain is broken individuals will not adopt such voluntary practices. There are no known political or geographical barriers to human copulation; now is the time to act particularly in countries with a low or no prevalence of AIDS. Obstetricians must fight AIDS with the same commitment to preventative medicine that they bring to good obstetrics and good family planning.
Short-Range Test of the Equivalence Principle

We rotated a 3 ton {sup 238}U attractor around a compact torsion balance and compared the accelerations of Cu and Pb toward U. We found that a{sub Cu}-a{sub Pb}=(-0.7{plus_minus} 5.7){times}10{sup -13}cm/s{sup 2}, compared to the 9.8{times}10{sup -5}cm/s{sup 2} gravitational acceleration toward the attractor. Our results set new constraints on equivalence-principle violating interactions with Yukawa ranges down to 1cm and rule out an earlier suggestion of a Yukawa interaction coupled predominantly to N-Z. {copyright} {ital 1997} {ital The American Physical Society}
Laboratory scale-up of two-stage laser chemistry separation of13C from CF2HCl

The laboratory scale-up of a two-stage laser enrichment process for carbon isotopes, involving infrared multiphoton dissociation of freon-22, is described. Unmodified commercial equipment and materials were used. An initial study of the effect of fluence, laser frequency, freon-22 pressure and pressure of argon, nitrogen and trifluoromethyl chloride was made in short irradiation cells (constant fluence) in order to define optimum process parameters. The process was then scaled to higher throughput in longer cells (1–5 m) in which compensation for beam-energy depletion by absorption was made by reduction in the beam area by focussing. From the scale-up experiments, measurements of yield and enrichment of the tetrafluoroethylene product gave demonstrated production rates. These, coupled with measurements of the absorption, allowed extrapolation to production rates assuming total utilization of the available output energy. Using a 100 W TEA CO2 laser (10 J, 10 Hz) we have demonstrated production rates of 0.20 g h−1 carbon-12 at 99.99% carbon-12, 11 mg h−1 carbon-13 at 72% carbon-13 and 2 kg per annum carbon-13 at 50%. Energy absorption measurements imply a capability to produce 3 kg per annum carbon-13 at over 95% carbon-13 in a two-stage process. The apparatus was used to produce gram quantities of carbon-13 depleted freon-22 (99.99% carbon-12). A comparison of the infrared multiphoton dissociation of this material with that of natural freon-22 (1.11% carbon-13) showed that under the conditions required to give selective dissociation of13CF2HCl that12CF2HCl was excited as a result of a dominantly radiative interaction and that collisional transfer from13CF2HCl molecules played a minor role.
Improved Synthesis of N1-Substituted Orotic Acid Derivatives (III)

involving the direct formation of 5-bromouracil (II) from dihydrouracils (I) as the key step
Engaging health care providers in coalition activities.

Health care providers play a key role in promoting and participating in asthma coalition activities. Barriers to participation include lack of time, concern about coalition effectiveness, and unfamiliarity with communitybased approaches to health issues. Despite this, the Allies Against Asthma coalitions were successful at involving health care providers in leadership roles, on advisory committees, and as research and clinical experts. Successful engagement strategies included presentation of data illustrating need for improved asthma care, identification of clinicians who were involved in caring for children with uncontrolled asthma, and education regarding the added value of a coalition and benefits of participation. Despite barriers to participation, health care providers felt that their participation in asthma coalitions helped them to develop collaborative relationships with other agencies, increase their professional knowledge and skills with regard to asthma management, and improve access to priority populations.
Phosphorylation of protein tyrosine by human erythrocyte casein kinase A

Summary Human erythrocyte casein kinase A, previously identified as a seryl, threonyl kinase, was found also to catalyze the phosphorylation of protein tyrosine. Phosphorylation of tyrosyl residues was detected in angiotensin-II and in several tyrosine containing synthetic peptides. In addition, phosphorylation on tyrosyl residues was also observed in alkylated bovine serum albumin and in band 3 and ankyrin purified from human erythrocyte membranes. The identification of phosphotyrosine was conducted using two-dimensional thin layer electrophoresis at pH 1.9 and 3.5 after acid hydrolysis of the phosphoproteins. It should be noted, however, that the major phosphorylation sites in band 3 and ankyrin catalyzed by casein kinase A were seryl and threonyl residues.
Foreign aid and poverty in Bosnia and Herzegovina: Targeting simulations and policy implications

Abstract Though the current aid program has reached many of the poor, it has also excluded a sizable part of the neediest. By using simple proxy means tests approach we show that improving targeting accuracy in the aid delivery process can yield improved coverage and reduced leakage and can have a sizable impact in terms of poverty reduction. We focus on some variables that are relevant in Bosnia and Herzegovina. The data come from a household survey commissioned by the World Bank that covers about 7000 households and is the first of its kind in the country.
Natural Variation in Fish Transcriptomes: Comparative Analysis of the Fathead Minnow (Pimephales promelas) and Zebrafish (Danio rerio).

Fathead minnow and zebrafish are among the most intensively studied fish species in environmental toxicogenomics. To aid the assessment and interpretation of subtle transcriptomic effects from treatment conditions of interest, better characterization and understanding are needed for natural variation in gene expression among fish individuals from lab cultures. Leveraging the transcriptomics data from a number of our toxicogenomics studies conducted over the years, we conducted a meta-analysis of nearly 600 microarrays generated from the ovary tissue of untreated, reproductively mature fathead minnow and zebrafish samples. As expected, there was considerable batch-to-batch transcriptomic variation; this “batch-effect” appeared to differentially impact subsets of fish transcriptomes in a nonsystematic way. Temporally more closely spaced batches tended to share a greater transcriptomic similarity among one another. The overall level of within-batch variation was quite low in fish ovary tissue, making it a suitable system for studying chemical stressors with subtle biological effects. The observed differences in the within-batch variability of gene expression, at the levels of both individual genes and pathways, were probably both technical and biological. This suggests that biological interpretation and prioritization of genes and pathways targeted by experimental conditions should take into account both their intrinsic variability and the size of induced transcriptional changes. There was significant conservation of both the genomes and transcriptomes between fathead minnow and zebrafish. The high degree of conservation offers promising opportunities in not only studying fish molecular responses to environmental stressors by a comparative biology approach, but also effective sharing of a large amount of existing public transcriptomics data for developing toxicogenomics applications.
Autonomous Work Groups: A Field Study of Correlates of Satisfaction:

In a single corporation 137 members of autonomous work groups completed a self-rating questionnaire on satisfaction. Scores were correlated with receptivity to change (.85), trust in management (.58), satisfaction with communication (.61), and with organizational commitment (.73).
Three-Body Leptonic Decays of the K Mesons

A treatment is given of the three-body leptonic decays of the $K$ mesons on the basis of a phenomenological strangeness-changing weak-interaction Hamiltonian and an analysis is presented of the relevant decay form factors in terms of simple assumptions regarding the groups of eigenstates which are strongly coupled to the $K\ensuremath{\pi}$ system. The possibility of a violation of time-reversal invariance arising from the "out of phaseness" of the strangeness-changing $\ensuremath{\Delta}T=\frac{3}{2}$ and $\ensuremath{\Delta}T=\frac{1}{2}$ currents in ${H}_{\mathrm{weak}}$ is considered. Throughout the discussion, the available experimental data are used to extract as much information as possible about the parameters which are important theoretically.
The complete mitochondrial genome sequence of the hornwort Megaceros aenigmaticus shows a mixed mode of conservative yet dynamic evolution in early land plant mitochondrial genomes.

Land plants possess some of the most unusual mitochondrial genomes among eukaryotes. However, in early land plants these genomes resemble those of green and red algae or early eukaryotes. The question of when during land plant evolution the dramatic change in mtDNAs occurred remains unanswered. Here we report the first completely sequenced mitochondrial genome of the hornwort, Megaceros aenigmaticus, a member of the sister group of vascular plants. It is a circular molecule of 184,908 base pairs, with 32 protein genes, 3 rRNA genes, 17 tRNA genes, and 30 group II introns. The genome contains many genes arranged in the same order as in those of a liverwort, a moss, several green and red algae, and Reclinomonas americana, an early-branching eukaryote with the most ancestral form of mtDNA. In particular, the gene order between mtDNAs of the hornwort and Physcomitrella patens (moss) differs by only 8 inversions and translocations. However, the hornwort mtDNA possesses 4 derived features relative to green alga mtDNAs—increased genome size, RNA editing, intron gains, and gene losses—which were all likely acquired during the origin and early evolution of land plants. Overall, this genome and those of other 2 bryophytes show that mitochondrial genomes in early land plants, unlike their seed plant counterparts, exhibit a mixed mode of conservative yet dynamic evolution.
Wireless mesh networking games

We address the coverage range extension of Wireless Mesh Networks (WMNs) by motivating traffic relaying by in-range network subscribers. Two different game models for non-cooperative users are discussed: a primary market model in which all in-range and out-of-range customers subscribe to one provider, and a primary-secondary market model in which some in-range customers are secondary providers and sell resources to out-of-range users. For the first market type, the relays may engage in packet-dropping for their own throughput gain, but we justify why this would likely not occur in the second market type. In both market models, we analyze the dynamics of the price charged by each provider and the traffic demanded by each subscriber. Additionally, we discuss possible options for underlying MAC protocols that are suitable for the games in play. We use an ALOHA-based framework to study the dynamics of the primary market, and an OFDMA-based framework to study the dynamics of the primary-secondary market. Lastly, we provide a simulation study for each model.
Structure of chromium oxide ultrathin films on Ag(1 1 1)

Abstract Epitaxial chromium oxide films are grown on Ag(1 1 1) by serial deposition. This method is repeated sequences of the deposition of sub-monolayer Cr films (typically ⩽0.5 ML) followed by oxidation. The procedure is repeated until the desired oxide film thickness is achieved. The oxide films are characterized using low-energy electron diffraction (LEED), X-ray photoelectron spectroscopy (XPS), and X-ray photoelectron diffraction (XPD). Chromium oxide films with thickness less than approximately 5 A show a p(2 × 2) LEED pattern consistent with Cr 3 O 4 (1 1 1) films. XPD results, however, suggest that the low coverage chromium oxide films may not be Cr 3 O 4 , and definitive identification of the low coverage oxide structure requires further work. Chromium oxide films with thickness greater than approximately 12 A show a (√3 × √3) R 30° LEED pattern consistent with α-Cr 2 O 3 (0 0 0 1). XPD results confirm this and further identify the surface termination as a single Cr layer with an inward relaxation of 50%.
The Prophylactic Use of Inferior Vena Cava Filters in Patients Undergoing High-Risk Spinal Surgery

Prophylactic inferior vena cava filter (IVCF) placement is advocated in some high-risk groups. We sought data regarding safety and efficacy for prophylactic IVCF placement in patients at high risk for venous thromboembolism (VTE) following major spinal reconstruction. Seventy-four spine surgery patients with contraindication to anticoagulation (44 females, 30 males; mean age 56.2) received prophylactic IVCFs. Criteria were (1) history of thromboembolism, (2) diagnosed thrombophilia, (3) malignancy, (4) bedridden >2 weeks prior to surgery, (5) staged procedures or multiple levels, (6) combined anterior/posterior approaches, (7) expected need for significant iliocaval manipulation during exposure, and (8) single-stage anesthetic time >8 hr. Seventy patients had at least two risk factors. All received IVCFs prior to the first stage of spine reconstruction. Patients were evaluated for filter complications, deep vein thrombosis (DVT), and pulmonary embolism (PE). Patients' lower extremity veins from groin to ankle were imaged weekly until discharge using duplex ultrasound (DUS). One-third also underwent thoracic and pelvic computed tomography scans, and the pelvic veins, IVC, and pulmonary vasculature were evaluated for VTE. Multiple DUS (n = 198, mean 2.6 studies per patient) were performed in 68 patients. At a mean follow-up of 11 months, one of the patients developed PE. Twenty-seven limbs in 23 patients developed DVT. Five limbs had isolated calf DVT, and 22 had proximal vein involvement. Insertion site DVT accounted for nearly one-third of the DVTs. Six patients died from unrelated complications. There was one technical error with an IVCF deployed in the iliac vein. Despite a high incidence of DVT following high-risk spinal surgery, prophylactic IVCF placement appears to protect patients from PE.
Radiation and scattering from complex 3D curvilinear geometries using a hybrid finite element-integral equation approach

The radiation and scattering properties are examined for arbitrary curvilinear geometries with very general material composition using parametric cubic geometry representations. The hybrid finite element-integral equation approach is used to take advantage of the strengths of each method. The regions of material composition are handled with the finite element method, since it can readily handle general inhomogeneous material composition. This method is then coupled to an integral equation formulation on the surface of the scatterer, since integral equations are well suited to handle the exterior domain. Both methods are formulated in generalized coordinates, and geometry input can be obtained from several commercial geometry software packages. >
Topography and sediments of a small area of the continental slope south of Martha's Vineyard☆

Abstract A small area of the continental slope off the northeastern United States between depths of 950 and 1750 m was studied from both a surface ship and a research submarine. The area borders the Alvin Submarine Canyon. It is smooth except for partial dissection by a tributary of the canyon and by some small gullies. Among the unexpected findings was a series of six long low ridges that extend directly downslope and across the observed bottom current. The origin of the ridges is unknown. Most of the smaller topographic features are due to activities of animals. Currents of 70 cm/sec have been ineffective in shaping the bottom.
Life in the hot zone around Chernobyl.

A consequence of the Chernobyl nuclear accident is an increased rate of inherited mutation in mammals (including humans) living in the region. But the causes and the long-term effects on health remain unclear.
A security architecture for transient trust

In extraordinary situations, certain individuals may require access to information for which they are not normally authorized. For example, to facilitate rescue of people trapped inside of a burning building, firefighters may need its detailed floor plan - information that may not typically be accessible to emergency responders. Thus, it is necessary to provide transient trust so that such sensitive information is available to selected individuals only during the emergency. The architecture presented here is designed to support transient trust. It encompasses pre-positioned, updateable domains for use exclusively during emergencies along with a set of "normal" domains with different sensitivity levels. Allocated to partitions, these domains are entered via a high integrity trusted path service located in a separate trusted partition. Interaction among subjects in different partitions is controlled by a high assurance separation kernel, and efficient use of devices is achieved through the application of a three-part device model. The resulting architecture enforces mandatory security policies, yet ensures secure and revocable access to a class of information during declared emergencies.
Sociocultural Orientations and the Mathematical Success of African American Students

The author reported research findings from a study that critically examined the role of sociocultural orientations in the mathematical experiences of 2 African American students. To determine how the orientations influenced the students' mathematical success, the author used a phenomenological research strategy to examine the life histories of the students. The author highlighted the African American students' perceptions of and responses to their mathematical experiences by emphasizing their experiences in mathematics classrooms. Results of the study suggest that the ways in which students perceive and respond to schooling influence their success in mathematics. Data also suggest that African American students do not perceive and respond to schooling in the same way by virtue of being African American, thus implying that African American students may belong to many different cultures. Finally, the results of the study suggest that the ways in which African American students view (a) membership in particu...
Primary and secondary trimethylsilylmethylstibines. Synthesis, characterization and chemical vapor deposition properties

The primary and secondary trimethylsilylmethylstibines (trimethylsilylmethyl = Me3SiCH2-) (Me3SiCH2)SbH2 and (Me3SiCH2)2SbH have been synthesized by the reduction of a corresponding dihalo- and monohaloantimony compound, respectively. Trimethylsilylmethylstibine was prepared by the reduction of (Me3SiCH2)SbBr2 with lithium aluminum hydride (LAH) in tetraglyme. The primary stibine is highly air-sensitive and exhibits a vapor pressure of 2.0 Torr at O°C. Bis-(trimethyl-silylmethyl)stibine was synthesized by the LAH reduction of either (Me3SiCH2)2SbBr or (Me3SiCH2)2SbI in diethyl ether. The secondary stibine is less sensitive to air than (Me3SiCH2)SbH2 but nonetheless decomposes quickly when exposed to air. The detailed synthesis, spectroscopic characterizations and physical properties of both stibines, as well as the preliminary chemical vapor deposition experiments of (Me3SiCH2)SbH2, are discussed.
Community-acquired methicillin-resistant staphylococcus aureus skin infection: an emerging clinical problem

Community-acquired methicillin-resistant Staphylococcus aureus skin infections at an outpatient university health center were evaluated. In all, 41 cultures were performed in 36 of 853 patients. Of the 19 patients with S aureus infection, methicillin resistance occurred in 10 (53%) and generally manifested as abscesses or cellulitis. Therefore, methicillin resistance should be considered, even in the community setting, and appropriate cultures performed.
Effect of Combination Treatment of Rapamycin and Isoflavones on mTOR Pathway in Human Glioblastoma (U87) Cells

Glioblastoma Multiforme (GBM) is a malignant primary brain tumor associated with poor survival rate. PI3K/Akt pathway is highly upregulated in gliomas due to deletion or mutation of PTEN and its activation is associated with tumor grade. mTOR is downstream from PI3K/Akt pathway and it initiates translation through its action on S6K and 4E-BP1. mTOR is an important therapeutic target in many cancers, including glioblastomas. Rapamycin and its analogues are known to inhibit mTOR pathway; however, they also show simultaneous upregulation of Akt and eIF4E survival pathways on inhibition of mTOR, rendering cells more resistant to rapamycin treatment. In this study we investigated the effect of combination treatment of rapamycin with isoflavones such as genistein and biochanin A on mTOR pathway and activation of Akt and eIF4E in human glioblastoma (U87) cells. Our results show that combination treatment of rapamycin with isoflavones, especially biochanin A at 50 μM, decreased the phosphorylation of Akt and eIF4E proteins and rendered U87 cells more sensitive to rapamycin treatment when compared to cells treated with rapamycin alone. These results suggest the importance of combining chemopreventive with chemotherapeutic agents in order to increase the efficacy of chemotherapeutic drugs.
On the Translatory Whirl Motion of a Vertical Rotor in Plain Cylindrical Gas-Dynamic Journal Bearings

Abstract : The determination of the bearing fluid film forces in a rotor system under dynamical conditions is discussed. In the case of a vertical rotor operating in a gaseous medium in plain cylindrical journal bearings, the steady whirl approximation is appropriate. In the steady whirl approximation, a set of rotating coordinates is employed, and the time dependence of the Reynolds equation is eliminated. At the same time, the compressibility number, Lambda, is replaced by the quantity (1-2 alpha/omega) multiplied by lambda. This approximation applies when both whirl acceleration and the radial velocity of the shaft are small. The attitude angle of the fluid film force is strongly dependent on the whirl motion. Experimental data of synchronous whirl agrees with the theoretical calculations based on the steady whirl analysis. A perfectly balanced vertical rotor in a plain gas dynamic journal bearing is always unstable with respect to the half frequency whirl.
ELECTRON PARAMAGNETIC RESONANCE DETECTION OF SOLITONS IN TWO-DIMENSIONAL MAGNETS

It has previously been assumed that spin waves were the dominant excitations in lower-dimensional magnets. Recently, however, it has been shown that nonlinear excitations or solitons rather than spin waves influence the dynamic thermal quantities such as the spin correlation function which can be investigated experimentally through the electron paramagnetic resonance linewidth. In this review the influence of both spin waves and solitons on the temperature-dependent linewidth in the fluctuation region immediately above the ordering temperature is discussed. It is seen that both excitations result in a theoretical Arrhenius temperature-dependence, (∆H~exp(E/T) where E=6πJs2 for spin waves and E=4πJs2 for solitons, J is the nearest neighbor exchange constant, and s is the value of the spin. In experiments, quantum (s=1/2) layered copper compounds exhibit the temperature dependence expected from spin waves even though nonlinear excitations have been shown to exist in these systems. On the other hand nearly classical (s=5/2) manganese compounds have the temperature dependence expected from solitons. The calculation of the linewidth from both spin waves and solitons is reviewed and compared with experimental data to show that solitons dominate the dynamics of the layered, nearly classical magnet.
Blood flow and progestin levels in the ovaries of the pregnant rabbit.

Blood flow and progestin levels in corpora lutea and in the ovaries minus corpora lutea (interstitial gland) were determined in pregnant New Zealand rabbits having one nongravid uterine horn. Corpora lutea weight, interstitial gland weight, progestin levels in the ovary and blood flow in the corpora lutea and interstitial gland were similar in the 2 ovaries between days 5 and 25. The ratio of 20a-hydroxypregn- 4-en-3-one (20a-OH) to progesterone was 4-16 times higher in the interstitial gland than in the corpora lutea. Blood flow rates in the corpora lutea were highest at day 10, decreasing significantly at later stages. Blood flow rates in the interstitial gland were relatively constant throughout pregnancy. These results indicate that one nongravid horn has no differential or local effect on the ipsilateral ovary during pregnancy in the rabbit. (Endocrinology 88: 821, 1971)
QCD prediction for the structure functions of the photon

We compute the unpolarized deep inelastic structure functions of the photon in an asymptotically free gauge theory, including mass effects. We show that when the momentum squared of the struck photon is small relative to the contributing quark mass, m, the free quark model prediction is obtained to O(1/ln(Q2/m2)) and (g2ln(Q2/m2)). For the light quark contribution the perturbation expansion does not converge. For large momentum squared of the struck photon the free quark model result is renormalized by a finite amount computable in QCD. For forseeable experimental ranges ofQ2 this renormalization is small.
Effect of Atrial Fibrillation and an Irregular Ventricular Response on Sympathetic Nerve Activity in Human Subjects

Background— Although the hemodynamic changes associated with atrial fibrillation (AF) have been extensively studied, the neural changes remain unclear. We hypothesized that AF is associated with an increase in sympathetic nerve activity (SNA) and that the irregular ventricular response contributes to this state of sympathoexcitation. Methods and Results— In 8 patients referred for an electrophysiological study, SNA, blood pressure (BP), central venous pressure (CVP), and heart rate were recorded during 3 minutes of normal sinus rhythm (NSR) and 3 minutes of induced AF. In 5 of 8 patients who converted to NSR, right atrial (RA) pacing was performed for 3 minutes in atrial pacing triggered by ventricular sensing mode triggered by playback of an FM tape previously recorded from the right ventricle during AF (RA-irregular) and atrial pacing inhibited by atrial sensing mode at a rate equal to the mean heart rate obtained during AF (RA-regular). SNA data were expressed as percentage of baseline during NSR. SNA ...
The REACH Project of the Adolescent Medicine HIV/AIDS Research Network:: Design, Methods, and Selected Characteristics of Participants

Abstract Purpose: To describe the Reaching for Excellence in Adolescent Care and Health (REACH) Project of the Adolescent Medicine Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) Research Network, a unique collaborative effort to conceive and implement a research design intended to examine HIV pathogenesis, pubertal hormonal variation, and the effects of sexually transmitted disease comorbidity in HIV-infected youth to improve their health care. Methods: This multidisciplinary team has drawn on basic science and clinical experience to produce a study design with relevant and feasible study aims and testable hypotheses. Particular attention has been paid to centralized training and quality control practices. Standardized measurements include direct and computer interviews, physical examination, laboratory analysis, and medical chart abstraction. The protocol has been approved by local institutional review boards. Results: A highly standardized and quality control monitored protocol has been implemented at 16 sites throughout the United States collecting historical, observational, and laboratory data in a group of HIV-infected adolescents and HIV-negative controls. Preliminary data collected on subjects are consistent with published reports of the sociodemographic and clinical characteristics of the HIV epidemic in sexually active youth, thus supporting the integrity of the protocol development process. The study population is, for the most part, in older adolescence, predominantly minority and female, and with publicly financed or no health insurance. Conclusions: The REACH Project is positioned to address questions about the clinical course, immunologic profile, and viral dynamics in HIV-positive youth, and thus is able to inform drug development and management strategies for this understudied population.