cssi/SciSciGPT-SciSciNet huggingface dataset:
The Snowbird Charrette: Integrative Interdisciplinary Collaboration in Environmental Research Design

The integration of ideas, methods, and data from diverse disciplines has been a transformative force in science and higher education, attracting policy interventions, program innovations, financial resources, and talented people. Much energy has been invested in producing a new generation of scientists trained to work fluidly across disciplines, sectors, and research problems, yet the success of such investments has been difficult to measure. Using the Integrative Graduate Education and Research Training (IGERT) program of the U.S. National Science Foundation as a strategic research site, we conducted an experiment to determine whether and how the process and products of research of IGERT-trained scientists differ from those of scientists trained in disciplinary graduate programs. Among scientists in the early years of graduate study we found substantial and consistent differences suggesting that interdisciplinary training improved the quality and process of research, but this pattern was equally strongly reversed among students in the latter years of graduate study. Using systematic observation and other data we suggest why this might be so, then discuss the implications of these results for the design and conduct of graduate education and research.
The structure of social substitutions: a test of relational models theory

People often select a substitute to replace an intended interactant, thereby revealing how they represent their social intentions. Naturally-occurring substitutions preserved the relational model governing the interaction but not the characteristics of individual participants, indicating that social intentions are formulated in terms of relational rather than individual characteristics. © 1997 John Wiley & Sons, Ltd.
Nickel suicide for source-drain contacts from ALD NiO films

In this work, we demonstrate the preparation of nickel monosilicide (NiSi) layers on silicon using a conformal NiO ALD process and thin sacrificial Ge interlayers. The interlayers protect the underlying Si from oxidizing during the NiO growth, while allowing for Ni diffusion during a silicidation anneal. The NiSi layers prepared have low amounts of impurities and near bulk resistivities, therefore making the processes promising candidates for applications in advanced semiconductor devices where high quality NiSi layers are needed, such as source-drain contacts. Good step coverage provided by ALD enables their use for example in non-planar transistors such as FinFETs and other multi-gate transistors with complex topographies.
Factors affecting transient gene expression in electroporated Glycine max protoplasts

Electroporation was used to evaluate parameters affecting transient gene expression in Glycine max protoplasts. Protoplast viability and reporter enzyme activity for chloramphenicol acetyl transferase (CAT) and s-glucuronidase (GUS) depended on the field strength employed. Maximum CAT and GUS activity was obtained when a field strength of 500 V/cm at 1000 μF and a protoplast concentration of 1–3 × 106/ml was used. Transformation efficiencies up to approximately 1.6% GUS positive protoplasts were obtained. Transient gene expression increased with increasing plasmid DNA concentration and with the time after electroporation, reaching a maximum after 48 hr. Addition of polyethylene glycol at 5.6% and heat shock (5 rain at 45 °C) given to the protoplasts before adding DNA further enhanced the transformation efficiency. Under the optimized experimental conditions, CAT and GUS activity increased simultaneously, thereby indicating that the increased expression is caused by DNA uptake by more cells rather than greater DNA uptake by the same cells. Our results demonstrate that both GUS and CAT can be used as efficient screenable markers for transformation studies in soybean.
Foveal and parafoveal cone electroretinograms in juvenile macular degeneration

Focal cone electroretinograms were elicited with a hand-held two-channel, stimulator-ophthalmoscope from 46 patients with autosomal recessive juvenile macular degeneration. Log foveal cone ERG amplitude and log b-wave implicit time were both significantly correlated with log Snellen visual acuity; amplitudes were smaller and implicit times longer in patients with lower visual acuities. Patients with visual acuities of 20/20 to 20/25 and minimal, if any, visible fundus abnormalities often showed abnormal foveal cone Erg responses which resembled in amplitude and implicit time the parafoveal responses of normal subjects. These findings raise the possibility that patients with the early stages of juvenile macular degeneration have foveal cones that are reduced in number and shortened with respect to outer segment length. Some of these patients had abnormal parafoveal cone ERGs; the degree of parafoveal malfunction did not appear to be correlated with the reduction in visual acuity.
Data sources for microcomputer component selection

Abstract The technology related to microcomputers is rapidly changing and has facilitated equally rapid changes in the power and utility of microcomputers. This constantly changing environment causes major problems when selecting a microcomputer. Does one select the most advanced and sophisticated computer or does one select a computer based solely on current and projected needs? This paper presents methods for determining desired operating characteristics and discusses information sources for determining component compatibility.
Conversion of a phosphorylated ketohexose (D-fructose 6-phosphate) to a phosphorylated aldopentose derivative (D-arabonic acid 5-phosphate).

Abstract It is established that the product of oxidative degradation of d -fructose 6-phosphate is d -arabonic acid 5-phosphate.
Strength of fixation constructs for basilar osteotomies of the first metatarsal.

Twenty-four pairs of fresh-frozen human feet had a proximal osteotomy of the first metatarsal that was fixed using either screws, staples, or K wires. Each metatarsal was excised and the specimen w...
Beta-Propiolactone as a Virus Altering Agent for a Newcastle Disease Vaccine

Abstract THE criteria for a satisfactory vaccine to protect an animal from a specific disease are: 1. the vaccine, when injected, should be incapable of producing the disease in a susceptible animal; 2. it should protect the animal against the specific naturally occurring disease in question for an adequate period; 3. the vaccine or end products should not be toxic or produce unwanted reactions. The problem of producing a satisfactory vaccine therefore centers around the methods of altering the pathogenicity of the disease-producing agent without destroying its antigenicity. The altered substances involved must satisfy the three points as listed above. Beta-propiolactone has been found viricidal and of low toxicity by Mangun and his associates (1951). Hartman et al. (1954) demonstrated that a number of viruses are killed when treated with beta-propiolactone. When we treated Newcastle disease virus with beta-propiolactone and subsequently injected it into chickens, a highly satisfactory state of resistance …
Fibrillar electronically conductive polymers show enhanced rates of charge transport

Abstract : Many electronically conductive polymers can be reversibly switched between electronically insulating and electronically conducting states. For polyrrole, this redox switching reaction can be written as - (Pyrrole)-x+ Boron Tetrafluoride Anion 4- ---- -(Py+BF4(-)n - (PY)(x-n)- + ne(-) where Py and Py(+) are reduced and oxidized monomer unites in the polypyrrole film and BF4(-) is a charge balancing counter-ion, initially present in a contacting solution phase. Equation 1 shows that ions must be incorporated into, or expelled from, the polymer phase during the redox switching reaction. In many cases, the rate of this reaction is controlled by ion-transport in the polymer phase (3,4). The switching reaction plays an integral role in nearly all of the proposed applications of electronically conductive polymers (5-7). In most cases, significant benefit would accrue if the rate of this reaction could be accelerated. The above discussion suggests that one approach for enhancing the rate of the switching reaction would be to enhance the rate of charge-transport in the polymer phase. We would have recently described a procedure for controlling the supermolecular structures of electronically conductive polymers (8). This procedure yields polymers with fibrillar supermolecular structures. We have shown the polypyrrole films which have this fibrillar supermolecular structure support higher rates of reductive charge-transport than conventional polypyrrole films. We report preliminary results of these investigation in this communication. Electronically conductive polymers, Polypyrrole, Oxidized monomer units, Supermolecular, Fibrillar supermolecular structure. Charged particles.
The effect of dietary carbohydrate and fat on the synthesis of rat liver 6-phosphogluconate dehydrogenase

Abstract 1. 1. A kinetic method was used to estimate the rates of 6-phosphogluconate dehydrogenase synthesis and degradation in vivo in rats fed diets containing various levels of carbohydrate and fat. 2. 2. Switching rats from a commercial pellet diet to a synthetic diet containing 60% carbohydrate resulted in a io -fold increase in the rate of synthesis and a 6-fold increase in the rate of degradation of this enzyme. 3. 3. The extent of this induction and the increase in the rate enzyme synthesis is correlated with the caloric consumption of carbohydrate. 4. 4. Insulin and dietary fat increase and decrease, respectively, the rate of enzyme synthesis without effecting the rate of enzyme degradation and both appear to act indirectly by affecting the appetite.
Reticulocytes contain increased amounts of reduced glutathione except when produced by acetylphenylhydrazine.

Abstract The glutathione status (GSH) of mouse and human reticulocytes in comparison with that of older cells was investigated. Reticulocytosis in mice was induced either by repeated bleeding or a single large dose of acetylphenylhydrazine (APH). Blood samples from humans were obtained from patients with a variety of acquired and inherited anemias associated with an increased reticulocyte count. The human cells were fractionated by simple centrifugation into top, middle, and bottom layers. Bled mice attained a reticulocyte count of 30% and displayed a red cell GSH content two- to threefold greater than control values. APH-Injected mice attained, in some cases, reticulocyte counts of 100% and displayed no increase in red cell GSH. CoCl 2 -Induced reticulocytosis also caused a small rise in GSH. In humans, reticulocyte-rich fractions were associated with a nearly twofold increase in GSH content when compared to reticulocyte-poor bottom layers. These data confirm some previous studies of human and animal reticulocytes and contradict other investigations in the same area. Although the utility of increased GSH levels remains obscure, increased GSH may be required for protein or heme synthesis and/or as protection against oxidative stresses which exceed those found in mature red cells.
Localization of the calcium-regulated citrate transport process in proximal tubule cells

Urinary citrate is an important inhibitor of calcium-stone formation. Most of the citrate reabsorption in the proximal tubule is thought to occur via a dicarboxylate transporter NaDC1 located in the apical membrane. OK cells, an established opossum kidney proximal tubule cell line, transport citrate but the characteristics change with extracellular calcium such that low calcium solutions stimulate total citrate transport as well as increase the apparent affinity for transport. The present studies address several fundamental properties of this novel process: the polarity of the transport process, the location of the calcium-sensitivity and whether NaDC1 is present in OK cells. OK cells grown on permeable supports exhibited apical >basolateral citrate transport. Apical transport of both citrate and succinate was sensitive to extracellular calcium whereas basolateral transport was not. Apical calcium, rather than basolateral, was the predominant determinant of changes in transport. Also 2,3-dimethylsuccinate, previously identified as an inhibitor of basolateral dicarboxylate transport, inhibited apical citrate uptake. Although the calcium-sensitive transport process in OK cells is functionally not typical NaDC1, NaDC1 is present in OK cells by Western blot and PCR. By immunolocalization studies, NaDC1 was predominantly located in discrete apical membrane or subapical areas. However, by biotinylation, apical NaDC1 decreases in the apical membrane with lowering calcium. In sum, OK cells express a calcium-sensitive/regulated dicarboxylate process at the apical membrane which responds to variations in apical calcium. Despite the functional differences of this process compared to NaDC1, NaDC1 is present in these cells, but predominantly in subapical vesicles.
Network-adaptive video coding and transmission

In visual communication, the conditions of the network, such as the delay, delay jitter, and the packet loss rate, have strong impact to the video quality. It would be useful if there is a feedback channel from the client to the sever to indicate the network conditions periodically, and a smart mechanism for coding and transmitting video that can adapt to these conditions. For example, when the network is congested, instead of sensing all the packets that have a high probability of being lost in the network, we can selectively drop some packets at the server (such as dropping packets for bidirectional-predicted frames). While intuitive, it is difficult to illustrate the effectiveness of adaptation using a single video server-client pair. A practical simulation would require multiple video servers and clients, and only then the benefit of adaptation will show up as advantageous utilization of network resources to provide good video quality. In this paper, we will introduce our methods of adaptation and present experimental and simulation results.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Phagocytic Clearance in Neurodegeneration

The cellular and molecular mechanisms of phagocytic clearance of apoptotic cells and debris have been intensely studied in invertebrate model organisms and in the mammalian immune system. This evolutionarily conserved process serves multiple purposes. Uncleared debris from dying cells or aggregated proteins can be toxic and may trigger exaggerated inflammatory responses. Even though apoptotic cell death and debris accumulation are key features of neurodegenerative diseases, relatively little attention has been paid to this important homeostatic function in the central nervous system (CNS). This review attempts to summarize our knowledge of phagocytic clearance in the CNS, with a focus on retinal degeneration, forms of which are caused by mutations in genes within known phagocytic pathways, and on Alzheimer's disease (AD). Interest in phagocytic clearance mechanisms in AD was stimulated by the discovery that immunization could promote phagocytic clearance of amyloid-β; however, much less is known about clearance of neuronal and synaptic corpses in AD and other neurodegenerative diseases. Because the regulation of phagocytic activity is intertwined with cytokine signaling, this review also addresses the relationships among CNS inflammation, glial responses, and phagocytic clearance.
Stability of double-integrator plants controlled using real-time SLAM maps

The position control of agents having double-integrator dynamic response, with explicit dependence on an estimator that simultaneously reconstructs agent states and refines a feature map, is considered. We show that under broad conditions the phase and gain margins of an equivalent control system based on absolute navigation sensors can be significantly eroded when the dynamic map is used. The closed-loop bandwidth achieved depends strongly on the bandwidth of the filter, which is in turn dictated by the ratio of process to sensor noise, on the control gains, and on the arrangement of features being tracked. The findings are relevant to the integration of SLAM algorithms in high-performance positioning of mobile agents. A specific example is the case undersea robots working near large structures, where traditional navigation systems may not be practical.
The tobacco mitochondrial ATPase subunit 9 gene is closely linked to an open reading frame for a ribosomal protein

A transcribed segment of mitochondrial DNA (mtDNA) from Nicotiana tabacum contains the F0-ATPase subunit 9 gene, an open reading frame with homology to the E. coli small subunit ribosomal protein S13 and an open reading frame with homology to a portion of the mammalian “URF 1” protein, recently shown to be a component of the NADH:ubiquinone reductase complex (NADH:Q 1). The transcriptional patterns of the tobacco ATPase 9 gene and S13-like open reading frame share eight RNA species indicating the two sequences are part of the same transcriptional unit. A maize mtDNA fragment contains the S13 homologous sequence and the NADH:Q 1 homologous sequence in an orientation similar to tobacco. The S13-like sequence is present as a single copy in maize and tobacco, as two copies in wheat, and is absent in pea and bean. We discuss the distribution and orientation of the S13-like and “URF 1”-like sequences and the possibility that they are active genes.
Cartesian powers of 3-manifolds

Previous results of the authors completely determine when the n-fold self-products of two 3-dimensional lens spaces are diffeomorphic; in particular, if n is odd then the fundamental group determines the diffeomorphism type. We prove that for all other irreducible geometric 3-manifolds with trivial first Betti number, the n-fold products of such manifolds with themselves are homeomorphic for some n 2 if and only if the manifolds themselves are homeomorphic and obtain partial results for other cases. The proofs use an assortment of techniques from 3-dimensional topology and group theory. © 2006 Elsevier B.V. All rights reserved.
Run the robot backward

This paper reports on lessons learned in sensor placement and search strategies for nuclear forensics from a 2013 field exercise. Nuclear forensics, where a radiological source is located, has been the subject of theoretical research but only one reported instance with an actual robot (Fukushima). The field exercise specifically focused on source localization where a teleoperated Packbot 510 UGV Radiac AN/UDR-14 dosimeter was used to find a 1.48 GigaBecquerel cesium-137 source placed in a partially collapsed building. The operators were able to quickly find the correct room but not the source, spending 30 minutes searching a 6 by 6 m space due to inconsistent measurements. A detailed analysis of the logged data shows that the readings were more reliable and suitable for an autonomous search algorithm when the robot was driven backwards. This counter-intuitive result appears due to unfavorable sensor placement. However, given that all robots have limited areas that sensors can be mounted on and have metal parts, it may be unrealistic to focus on optimizing radiological sensor placement on non-holonomic platforms. Instead, this paper recommends research in autonomous localization strategies that will compensate for inevitable imperfect readings.
Vascular insulin abnormalities, hypertension, and accelerated atherosclerosis

There is accumulating evidence that insulin resistance, glucose intolerance, and hyperinsulinemia exist in people with high blood pressure, and it has been suggested that insulin resistance and hyperinsulinemia may be of great importance in the origin of hypertension and its ultimate clinical course. Of importance are the recent observations that persons with normal glucose tolerance, selected on the basis of hyperinsulinemia, had higher blood pressures than matched individuals with normoinsulinemia. Hypertension in insulin-resistant states generally has been attributed to hyperinsulinemia, with resulting increases in sympathetic nervous system activity. However, recent data from our laboratory suggest that cellular insulin resistance rather than hyperinsulinemia per se may lead to hypertension. The basic tenet proposed in this article is that a deficiency of insulin at the cellular level represents a common mechanism that is involved in the development of hypertension in both type I and type II diabetes mellitus. Insulin has an important role in the modulation of cellular calcium metabolism. Decreased insulin action on vascular smooth muscle cells may contribute both to hypertension and to accelerated atherosclerosis. Recent observations suggest that an impaired cellular response to insulin predisposes to increased vascular smooth muscle tone (the hallmark of hypertension in the diabetic state). For example, recently reported studies from our laboratory demonstrate that insulin attenuates the vascular contractile response to phenylephrine, serotonin, and potassium chloride. Thus, it appears that insulin normally modulates (attenuates) vascular smooth muscle contractile responses to vasoactive factors, and insulin resistance should accordingly be associated with enhanced vascular reactivity.
Opposing spin-canting mechanism in single-crystal Lu V O 3 and Y V O 3

A canted-spin ferromagnetic moment $\mathbf{M}$ parallel to the orthorhombic ($Pbnm$) $a$ axis of a $\mathrm{Y}\mathrm{V}{\mathrm{O}}_{3}$ single crystal changes sign from the direction of a measuring field $\mathbf{H}\ensuremath{\leqslant}1\phantom{\rule{0.3em}{0ex}}\mathrm{kOe}$ on warming from $5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ across a first-order orbital-spin reordering temperature ${T}_{CG}$; the magnetization changes sign again on warming across ${T}^{*}$ in the interval ${T}_{CG}l{T}^{*}l{T}_{N}$, where ${T}_{N}$ is the antiferromagnetic N\'eel temperature. Although the magnitude of $\mathbf{M}$ and its sign changes are the same for a sample cooled in a measuring field (FC) and zero-applied field (ZFC) to $5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, the $\mathbf{M}(T)$ curves differ for warming after FC and ZFC to just above ${T}_{CG}$; but the sign reversal of $\mathbf{M}$ occurs at the same ${T}^{*}$ with the same measuring field $\mathbf{H}$. These unusual features are argued to be the result of two coupled spin-canting mechanisms that oppose one another, an antisymmetric exchange operating on a $c$-axis spin component, and a 90\ifmmode^\circ\else\textdegree\fi{} site anisotropy in the $a\text{\ensuremath{-}}b$ plane operating on a $b$-axis component of the spin. The relative strength of the antisymmetric exchange increases with decreasing $\mathrm{V}\mathrm{O}\mathrm{V}$ bond angle to give a ${T}^{*}$ close to a ${T}_{OO}\ensuremath{\approx}{T}_{N}$ in $\mathrm{La}\mathrm{V}{\mathrm{O}}_{3}$ and no ${T}^{*}$ above ${T}_{CG}$ in $\mathrm{Lu}\mathrm{V}{\mathrm{O}}_{3}$.
Antibody response to oral polio vaccine in premature infants

APPROXIMATELY 50% OF TERM INFANTS will obtain protection to all three Serotypes of orally administered polio vaccine after a single dose at 2 months of age; multiple vaccine doses will increase the protection to 83% to 96% of children, v9 However, the optimal time to administer OPV to a child born prematurely has not been determined. The American Academy of Pediatrics recommends giving the first dose of OPV to a premature infant at 2 months of chronologic age if the child has been discharged from the hospital and is otherwise healthyJ ~ The Academy notes, however, that this recommendation is not based on adequate data. This study was undertaken to determine whether the antibody response in preterm infants to OPV given at 2 and 4 months of age is comparable to that in term infants.
A simple method for determining waist-to-waist transfer properties of quadrupole doublets and triplets☆

Abstract A new method is reported which allows the exact determination of the waist-to-waist transfer properties of quadrupole doublets and triplets. For any given geometry and finite emittance beam the entire set of available solutions can be found and the quadrupole strengths evaluated. Two examples are given for an asymmetric triplet, for the purpose of illustrating the application of the method.
Synthesis of squaraine-N-hydroxysuccinimide esters and their biological application as long-wavelength fluorescent labels

We synthesized two conjugatable long-wavelength fluorescence probes. They consist of a squaraine moiety, which is a cyanine- type chromophore with a central squarate bridge and a reactive N- hydroxysuccinimide group for coupling with amino functions. One form is water soluble due to the presence of a sulfobutyl group, the other is water insoluble. The water insoluble form was reacted with taurine to achieve water solubility and this squaraine-taurine conjugate displayed a very high binding affinity to BSA. The squaraines exhibit desirable properties of short lifetimes and low quantum yields in water, with a significant increase of lifetime and quantum yields when bound to proteins. Their absorption maxima around 635 nm in water and 640 nm when bound to proteins allow excitation with the newly commercially available diode lasers sources at 635, 645, and 650 nm. The spectral properties and photostabilities of the water soluble squaraine probes are compared with those of the commercially available CY5-NHS-ester.
Electric Field Effects of Photogenerated Ion Pairs on Nearby Molecules: A Model for the Carotenoid Band Shift in Photosynthesis

Photoinduced charge separation within a zinc porphyrin electron donor-pyromellitimide electron acceptor pair possessing an 8.4 A center-to-center distance and a linear orientation is shown to induce large electrochromic effects on the ground state absorption spectrum of a nearby carotenoid molecule. The orientation of the C-C backbone of the carotenoid is restricted relative to the direction of the electric field produced by the photogenerated ion pair. This is accomplished by covalently linking the electron donor-acceptor pair to the carotenoid with a calix[4]arene bridge. The bridge maintains its cone conformation resulting in an average dihedral angle of 35[degree] between the donor-acceptor axis and the C-C backbone of the carotenoid. Using picosecond transient absorption spectroscopy, a 15 nm electrochromic red shift in the ground state absorption spectrum of the carotenoid was readily observed during the 3.7 ns lifetime of the photogenerated ion pair. The magnitude of this shift depends on the dielectric constant of the surrounding solvent. The data are used to calculate an electric field strength of about 5.5 MV/cm at the carotenoid in toluene. The magnitude of the electric field produced by the ion pair at the carotenoid is larger than the highest fields that can be applied externally. 32 refs.,more » 6 figs., 1 tab.« less
Biological perspectives on the non‐surgical endodonfic management of periradicular pathosis

Differential radiographic criteria are unreliable for the histological diagnosis of periradicular lesions of pulpal origin. It should not, therefore, be assumed that large lesions or lesions with an opaque border are cystic. Even if cystic, or if strands of epithelium are present, the literature supports repair following the removal of the source of the pathosis. In most cases, the aetiological factors are oral contamination through the root canal or degenerating pulpal tissue. Therefore, the mere surgical removal of lesions of pulpal origin without removing the causes through proper root canal cleaning, shaping and obturation, will not result in the healing of the periradicular tissues. In addition to removing effectively the causative factors, environmental changes in the periradicular tissues caused by the process of canal debridement may inherently aid in the demise of epithelium, when present. The salient issues are discussed in light of thorough debridement of the root canal system, coupled with postulated mechanisms for the resolution of lesions displaying epithelial stands or cavities. Likewise, the role of calcium hydroxide and its potential role in the alteration of the periradicular environment is addressed, with support for the repair of large periradicular lesions without surgical intervention.
New transitions and precise energy and intensity determinations in the decay of 177mLu

Abstract The decays of 177 Lu (6.8 d) and 177m Lu (155 d) to excited states in 177 Hf and 177 Lu have been studied with a high-resolution, lithium-drifted germanium detector. Three new gamma rays have been placed in the decay scheme. Improved relative intensity measurements have allowed recalculation of E2/M1 mixing ratios and E1 branching ratios. Precise determination of the transition energies in 177m Lu decay has been made. The E1 transition probabilities in 177 Hf are compared with simple theory.
Thermal activation and viscosity

Creep behavior in superconductors is used to show how viscosity can affect thermally activated processes. In the case of a number of lead alloys the creep rate in the normal state is substantially less than in the superconducting state, in the temperature range where barriers control the creep process. This is explained through the temperature dependence of the electron damping of dislocations in the normal state compared to the superconducting state, and in the mixed superconducting state.
Mass transfer in turbulent impinging slot jets

Abstract The mass transfer characteristics of a turbulent slot jet impinging normally on a target wall are examined using numerical simulations. At the location where the slot jet emerges from the nozzle, a confinement plate is placed parallel to the target plate. The jet fluid is the same as the otherwise stagnant fluid into which the jet emerges. Fluid flow is modeled using the k–ω turbulence model of Wilcox [1] . The computations are validated against existing experimental fluid flow, heat transfer and mass transfer data. The range of Reynolds numbers examined is from 450 to 20 000 with Prandtl or Schmidt numbers from 1 to 2400. The distance of the target plate from the slot jet varies between 2 and 8 times the slot jet width. The study reveals computational aspects that are unique to the solution of flow and mass transfer problems with the combination of high Schmidt numbers and turbulent flows.
Symptom subtypes of obsessive-compulsive disorder in behavioral treatment studies: a quantitative review

Recent reviews and meta-analytic studies have provided an encouraging account of the effectiveness of behavioral interventions for obsessive-compulsive disorder (OCD). One question regarding these estimates concerns their degree of generalizability to the range of OCD subtypes encountered in clinical settings. The purpose of the present study was to provide a quantitative description of the prevalence of various OCD subtypes (i.e. type of compulsions) within the behavioral treatment literature. We examined 65 studies that permitted classification of patients according to symptom subtype. Patients with primarily cleaning and/or checking compulsions predominated, accounting for 75% of the treatment population. On the other hand, patients with multiple compulsions or other compulsions, such as exactness, counting, hoarding, or slowness rituals were underrepresented, comprising only 12% of the population, which is markedly less than clinical epidemiological estimates. Rates of improvements in patients with OCD are most applicable to patients with cleaning and checking compulsions, but may not yet be generalizable to patients with other symptoms. These findings encourage studies of the efficacy of existing and novel interventions for patients with counting, repeating, symmetry, hoarding, or multiple compulsions in order to broaden the clinical application of OCD behavioral treatment.
A surgical skills laboratory improves residents' knowledge and performance of episiotomy repair

Objective This study was undertaken to assess whether a surgical skills laboratory improves residents' knowledge and performance of episiotomy repair. Study design Twenty-four first- and second-year residents were randomly assigned to either a surgical skills laboratory on episiotomy repair or traditional teaching alone. Pre- and posttests assessed basic knowledge. Blinded attending physicians assessed performance, evaluating residents on second-degree laceration/episiotomy repairs in the clinical setting with 3 validated tools: a task-specific checklist, global rating scale, and a pass-fail grade. Results Postgraduate year 1 (PGY-1) residents participating in the laboratory scored significantly better on all 3 surgical assessment tools: the checklist, the global score, and the pass/fail analysis. All the residents who had the teaching laboratory demonstrated significant improvements on knowledge and the skills checklist. PGY-2 residents did not benefit as much as PGY-1 residents. Conclusion A surgical skills laboratory improved residents' knowledge and performance in the clinical setting. Improvement was greatest for PGY-1 residents.
Clinically significant magnetic interference of implanted cardiac devices by portable headphones.

BACKGROUND Little is known about the magnetic field strength of portable headphones and their potential to cause magnetic interference with implanted pacemakers (PMs) and implantable cardioverter-defibrillators (ICDs). OBJECTIVE The purpose of this study was to evaluate the magnetic field strength of portable headphones and to determine if they can cause clinically relevant magnetic interference. METHODS PM or ICD function was assessed in 100 patients during exposure to eight different models of portable headphones to determine the incidence of clinically relevant magnetic interference. The magnetic field strength of the headphones also was measured in vitro. RESULTS Clinically relevant magnetic interference from portable headphones occurred in 30 (30%) of 100 patients and more commonly affected ICD than PM patients (21/55 [38.2%] vs 9/45 [20.0%]; P .048). All patients affected by magnetic interference experienced a magnet response, characterized by asynchronous pacing in PM patients and by inhibition of tachyarrhythmia detection in ICD patients. In all but one of the 30 cases of magnetic interference, removal of the headphones from the patient’s chest immediately restored normal device function. Headphones with a measured magnetic field strength 10 gauss at 2 cm were much more likely to cause magnetic interference than were those with lower magnetic field strength (30/100 [30%] patients vs 0/100 [0%] patients; P .0001). Magnetic interference was not observed when headphones were placed 3 cm from the skin surface. CONCLUSION Clinically significant magnetic interference can occur when portable headphones are placed in close proximity to implanted PMs and ICDs. Patients with such a device should be advised to keep portable headphones at least 3 cm from their device.
Visual-vestibular interaction in humans during earth-horizontal axis rotation.

Visual-vestibular interaction using 60 percent constant velocity earth horizontal axis yaw rotation, simulating both the horizontal semicircular canals and the otolith organs, was measured in seven human subjects. Subjects were tested with their eyes open in the dark (EOD) while fixating upon a target rotating with them (FIX), and while observing stationary optokinetic stripes (VVR). Resulting nystagmus slow component velocity (SCV) was analyzed for EOD, FIX, and VVR conditions. It is concluded that the visual-vestibular interactions during EHA differ significantly from those during rotation about the vertical; specifically, there is a nonlinear interaction between linear acceleration and optokinetic nystagmus.
UNILATERAL PERINEAL ECTOPIC SCROTUM RESULTING IN DEBILITATING ORCHALGIA: DIAGNOSIS AND MANAGEMENT

Congenital scrotal anomalies are unusual, with ectopic and accessory scrota being the most rare. Scrotal ectopia, which has been described as resulting from an abnormal migration of the ipsilateral labioscrotal fold, is usually obvious and easily diagnosed in infancy.1 An 18-year-old male remained without diagnosis until exercise induced orchalgia led to the identification of an ectopic scrotum, which was a factor in the origin of the discomfort. The diagnosis and management of this case are described.
Classroom Characteristics and Student Friendship Cliques

This paper examines the effects of classroom characteristics on the friendship cliques of preadolescent students. We argue that structural and organizational features of a classroom constrain the interaction patterns of students in such a way as to affect features of the social network that evolves within a classroom. Hypotheses about the determinants of clique size, number of cliques, clique stability and the ability, sex and racial composition of cliques are tested on a large, longitudinal data set containing information on fourth through seventh grade students. The results show that the formation of student friendship cliques is more closely linked to classroom characteristics and to pedagogical practices than has previously been recognized. Moreover, the analyses indicate that the processes governing the establishment of cliques change over the school year as different features of the classroom experience become more salient to students.
Experimental study of active vibration suppression of flexible structure using modular control patch

This paper presents experimental results of vibration suppression of a flexible structure using a miniaturized digital controller, called modular control patch (MCP). The MCP employs a TI-C30 digital signal processor and was developed by TRW for the United States Air Force for future space vibration control. In this research, the MCP is used to implement different control algorithms for vibration suppression of a cantilevered aluminum beam with piezoceramic sensors and actuators. Positive position feedback (PPF) control, strain rate feedback (SRF) control, and their combinations were implemented. Experiments found that PPF control is most effective for single-mode vibration suppression, and two PPF filters in parallel are most effective for multi-mode vibration suppression. Further experiments demonstrated the robustness of PPF control. PPF can achieve effective vibration suppression when there is a 20% error in modal frequency.
A new interference in some digoxin assays: anti-murine heterophilic antibodies.

Background We describe a patient with cirrhotic liver disease and atrial fibrillation who was treated with spironolactone and digoxin. He was hospitalized because of an incidental finding of a high serum digoxin level (4.2 μg/L), but he remained asymptomatic without emerging arrhythmias. Despite discontinuation of both drugs, his serum digoxin level persisted at or above 3.0 μg/L for ~5 weeks, drawing into question the accuracy of the digoxin assay. Methods Additional digoxin methods gave lower, discrepant results, providing evidence of an assay interference, and several possible sources of digoxin false positivity were evaluated. This included assessment of the contribution of digoxin-like immunoreactive factor (DLIF), digoxin metabolites, and spironolactone. Because the routine digoxin assay used a monoclonal antibody, we also tested for another hypothetical interference: human heterophilic (“anti-mouse”) antibodies. Results We found no contribution from DLIF, dogoxin antibodies, or spironolactone to the apparent digoxin results. However, the use of protein A to complex and selectively remove immunoglobulin G molecules markedly lowered the apparent digoxin value, as did the less specific process of ultrafiltration. Conclusions These results suggest a previously unreported cause of digoxin false positivity: heterophilic antibodies, which have been reported to bind murine monoclonal antibodies in other assays. Because newer digoxin assays now use murine monoclonal antibodies, the possible presence of heterophilic, anti-mouse antibodies should now be considered in the interpretation of a high digoxin level. Clinical Pharmacology & Therapeutics (1996) 60, 593–598; doi:
Development of a new OFDM transceiver without guard interval

This paper develops a new orthogonal frequency division multiplexing (OFDM) receiver model that does not use the guard interval. This proposed technique (termed as preprocessing technique) is further extended to the IEEE 802.11a standard for wireless local area networks (WLANs) in this paper. The paper also addresses the other major OFDM receiver design issues, i.e., symbol detection, carrier frequency offset estimation, and channel estimation. The preamble approved by the IEEE 802.11a Standard is used to accomplish synchronization and estimation at the receiver. The paper compares the performance of the conventional OFDM system, which uses the guard interval with that of the newly proposed OFDM system that does not use the guard interval.
Patterns of sulfate reduction and the sulfur cycle in a South Carolina salt marsh

Rates of sulfate reduction and the magnitude of various sediment parameters related to the sulfur cycle were measured at about quarterly intervals for a 3-yr period at sites in a South Carolina salt marsh containing tall- or short-form Spartina alternij70ra. Sulfate reduction rates were greater at all times in the short-form sites and decreased markedly with depth. Seasonal changes were highly correlated with ambient temperature except in May and August when interactions with plants may have affected rates directly. In the short-form site, the annual integrated sulfate reduction rate accounted for about 47. 5–6 7 .OO/o of the estimated belowground plant production. Dissolved sulfides and pH varied seasonally in the short- but not tall-form sites; seasonal minima in the short-form site occurred during May and were probably due to oxidation of the sediment with the onset of plant production. Mechanisms resulting in oxidation were not evident however. Chromium-reducible sulfur, which is primarily pyrite, was substantially greater in the tall- than short-form site but apparently stable temporally at both sites. The differences in pool sizes of pyrite were probably due to differences in iron dynamics and the extent of sulfide oxidation. Microprofiles of dissolved oxygen were consistent with greater oxidation at the short-form site since the penetration of oxygen was deeper. Differences in sediment texture and tidal inundation may have contributed to greater oxygen inputs at the short-form site.
The prevalence of elevated hemoglobin A1c in patients undergoing coronary artery bypass surgery

Diabetes mellitus has become a major health issue in the United States and contributes to morbidity and mortality from coronary artery disease. Despite lifestyle changes and medications that have been shown to decrease complications and death, many persons have poor glycemic control. The purpose of this study is to determine the prevalence of elevated Hemoglobin A1c levels, a marker of glycemic control in patients presenting for coronary artery bypass surgery, and to determine if risk factors for diabetes mellitus could identify those patients with an elevated hemoglobin A1c. All patients undergoing coronary artery bypass surgery had hemoglobin A1c levels determined immediately preoperatively. Proportions were used to describe the number of patients with elevated levels. Linear regression and receiver operator characteristic curves were used to evaluate the accuracy of risk factors to identify patients with elevated levels. 83 of 87 (95%) diabetic patients had elevated A1c levels (≥ 6.0%), with 55 of 87 (63%) having inadequate control – A1c levels ≥ 7.0. 93 of 163 (57%) non-diabetic patients had elevated A1c levels (≥ 6.0%), with 19 (12%) having levels ≥ 7.0%. Risk factors for diabetes mellitus poorly predicted which patient had elevated A1c levels. The prevalence of elevated hemoglobin levels in patients undergoing coronary artery bypass surgery is high and routine measurement should be done to permit institution of lifestyle modifications and medication changes that decrease complications and death from diabetes mellitus.
Geostrophic fronts, bores, breaking and blocking waves

An undisturbed geostrophic density current flows along a vertical wall (the coast) with the free streamline (the front) located at a distance L from the wall which is comparable to the Rossby radius of deformation. Finite amplitude perturbations with downstream wavelengths much larger than L are discussed, and it is shown that the slope of the front in the horizontal plane increases with time. Some perturbations tend to ‘break’ seaward by developing large transverse velocities away from the coast. The temporal evolution of some perturbations is such as to completely ‘block’ the upstream flow, but the subsequent behaviour is beyond the scope of the theory. We also discuss the propagation of the nose of the intrusion when a density current debouches from a coastal source and then flows along the coastal boundary.
Some observations on the questions: is ventricular fibrillation chaos?

Abstract Ventricular fibrillation has been modeled as cardiac chaos occuring after a series of subharmonic bifurcations. However, previous experimental studies have suggested that fibrillatory oscillations have a relatively narrow-band frequency spectrum inconsistent with a turbulent process. Similarly, during the first minute of canine fibrillation we observed only a few localized frequency peaks from the epicardial and body surface electrocardiogram rather than a broadband type of spectrum as would be predicted for chaotic dynamics. Further narrowing of the frequency spectrum occured during the second minute of fibrillation. The frequency spectrum of ventricular fibrillation contrasts with scaled, broadband spectra observed in normal cardiac function. We suggest that ventricular fibrillation may serve as a general model for transitions from broadband stability to certain types of pathological periodicities in other physiological perturbations.
In Vitro Testing of Floating Light Activated Micro-Electrical Stimulators

Chronic tissue response to microelectrode implants stands in the way as a major challenge to development of many neural prosthetic applications. The long term tissue response is mostly due to the movement of interconnects and the resulting mechanical stress between the electrode and the surrounding neural tissue. Remotely activated floating micro-stimulators are one possible method of eliminating the interconnects. As a method of energy transfer to the micro-stimulator, we proposed to use a laser beam at near infrared (NIR) wavelengths. FLAMES of various sizes were fabricated with integrated silicon PIN photodiodes. Sizes varied from 120 (Width) × 300 (Length) × 100 (Height) µm to 200 × 500 × 100µm. Devices were bench tested using 850nm excitation from a Ti:Sapphire laser. To test this method, the voltage field of the FLAMES was experimentally tested in saline solution pulsed with a NIR laser beam. The voltage generated is around 196mV in peak at the cathodic contact as a response to a single pulse. When a train of laser pulses was applied at 100Hz, the peak voltage at the cathodic contact remained around 141mV suggesting the feasibility of this approach for applications with pulse frequencies up to 100Hz.