cssi/SciSciGPT-SciSciNet huggingface dataset:
Blending Functions in Hybrid Large-Eddy/Reynolds-Averaged Navier-Stokes Simulations

Several blending functions for use in hybrid large-eddy simulation (LES)/Reynolds-averaged Navier-Stokes (RANS) simulations of shock-separated flows are tested. The blending functions shift the turbulence closure from a k-ζ turbulence model near solid surfaces to a k − ∆ subgrid closure away from the wall. Three distinct forms for the blending function are developed: one that depends on the ratio of the von Karman length scale and the Taylor microscale, another that depends on the ratio of the RANS eddy viscosity to the subgrid eddy viscosity, and a third which replaces the von Karman length scale in the first form with the distance to the nearest wall. Comparisons are made for two cases: Mach 2.79 flow over a 20-deg compression corner and Mach 2.88 flow over a 25-deg compression/expansion corner. Inflow boundary conditions for all calculations employ the rescaling/reintroducing procedure developed by Xiao et al. (Xiao, X., Edwards, J. R., Hassan, H. A., and Baurle, R. A., "Inflow Boundary Conditions for Hybrid Large Eddy/Reynolds Averaged Navier-Stokes Simulations," AIAA Journal ,V ol. 41, No. 8, 2003, pp. 1481-1489) for hybrid LES/RANS simulations of wall-bounded flows. In general, the blending function based on the von Karman length scale gives the best results when compared with measured data. The skin friction predictions show the highest sensitivity to the various blending functions.
Partial serial-position constancy in nonserial paired-associate learning

Summary The role of serial-position cues in paired-associate learning was investigated by holding serial position of pairs in the list partially constant while preventing actual serial learning. Performance under conditions of partial serial-position constancy was compared with paired-associate learning involving unsystematic variation in serial order from trial to trial. In Experiment I, significant facilitation resulted if pairs were held constant in serial position only after being responded to correctly for the first time, largely due to a reduction in errors after the first correct response for the last-learned pairs. However, little evidence was found for differences among serial positions in rate of paired-associate learning. In Experiment II, if 2 or 4 pairs were held constant in serial position on all trials, while the remaining pairs were varied, significantly more errors resulted than under the standard varied-order procedure. It was concluded that serial-position cues may play a significant role in paired-associate tasks, and that the interfering effects of partial serial-position constancy in Exp. II resulted from the increasing difficulty of discriminating constant from varied pairs.
Seroprevalence of West Nile virus infection in solid organ transplant recipients.

A.G. Freifeld, J. Meza, B. Schweitzer, L. Shafer, A.C. Kalil. A.R. Sambol. Seroprevalence of West Nile virus infection in solid organ transplant recipients. Transpl Infect Dis 2010: 12: 120–126. All rights reserved Background. Of people infected with mosquito-borne West Nile virus (WNV), <1% develop neuroinvasive disease (NID). Population studies suggest that people older than 65 years may be at higher risk for neurologic symptoms. It has been suggested that solid organ transplant (SOT) recipients are also at higher risk for WNV NID, but definitive serologic and epidemiologic data are lacking. Methods. A serologic screening survey, using a US Food & Drug Administration-approved enzyme-linked immunosorbant assay to detect WNV immunoglobulin-G (IgG) antibody responses in cohorts of SOT recipients and non-immunocompromised controls, was undertaken at a large Midwestern university organ transplant center in the aftermath of the summer 2003 WNV regional outbreak. Hemagglutination-inhibition testing was used to confirm WNV IgG-positive results and differentiate them from positive results caused by Saint Louis encephalitis virus, another flavivirus that is endemic in the Midwestern US. Findings. The rate of WNV IgG-seropositive responses did not differ between SOT recipients and non-immunocompromised controls, and were 12% and 10%, respectively. Retrospective chart review showed no documented WNV NID in the seropositive SOT recipients, suggesting an incidence of WNV NID may be as low as 0.7% in this population. Interpretation. Asymptomatic WNV infection is common among immunocompromised SOT patients, occurring as often as it does in non-immunocompromised controls. Our data indicated that severe WNV NID is less frequent in SOT patients, contrary to what has been suggested in other studies.
INTEREXAMINER VARIABILITY OF DIGITAL RECTAL EXAMINATION IN DETECTING PROSTATE CANCER

Objectives. Digital rectal examination (DRE) is an important method of prostate cancer detection used by primary care physicians and medical specialists to identify patients in whom a prostatic biopsy is warranted. However, there is little empirical evidence assessing the degree of interexaminer variability in the use of DRE for the detection of prostate cancer. We addressed this issue within the framework of a prostate cancer screening study.
SBLAST: Structural Basic Local Alignment Searching Tools using Geometric Hashing

While much research has been done on finding similarities between protein sequences, there has not been the same progress on finding similarities between protein structures. Here we report a new algorithm (SBLAST) which discovers the largest common substructures between two proteins using a triangle-based variant of the geometric hashing of protein structures algorithm. The algorithm selects triples (triangles) of selected Ca atoms from all proteins in a protein structure database and creates a hash table using a key based on the three inter-atomic distances. Hash table hits from the triangles of a query protein are extended recursively to determine the largest common substructures less than a threshold deviation level (rmsd). Comparisons between a query protein and a preprocessed protein database can be performed in parallel. Because SBLAST does not rely on protein sequence alignment, common substructures can be detected in the absence of sequence conservation. SBLAST has been tested using the ASTRAL subset of the PDB.
Effects of sound on local transport from a heated cylinder

The steady transport of heat from a horizontal circular cylinder supported in a standing transverse sound field was investigated. Experimental conditions were chosen to allow ready comparison with solutions of the momentum and energy equations. Local heat transport was studied, it being more sensitive to sound fields than overall transport. Experiments were performed with a heated cylinder in an anechoic chamber and a laser schlieren-interferometer was used to obtain local measurements of temperature gradients in the air surrounding the cylinder. Sound field intensities ranged up to 142 db. The convection was analyzed in the equations for mean motion using the Reynolds stresses generated by the sound to represent the effect of the sound field. The velocity and temperature fields of the mean motion were represented as an azimuthal series of functions of the radial coordinate, and the solutions computed at finite Grashof and streaming Reynolds numbers for conditions at the bottom stagnation region. Substantial agreement was found between experimental transport and the computed solutions for horizontal sound fields. The analysis showed that the effect of the sound field is significantly greater at the moderate Grashof numbers (0 (103)) used in the experiments than predicted by a boundary layer analysis (Gr → ∞) for otherwise similar conditions. The results support the hypothesis that effects of sound and vibrations can be accounted as the influence on the mean motion of Reynolds stresses associated with the oscillations.
New Options for Usability Testing Projects in Business Communication Courses

The increasing availability of recording technologies makes it easier to include usability testing projects in business communication courses. Usability testing is a method of discovering whether p...
Real Land Rentals in Early Roman Egypt

Abstract This paper reexamines economic data from the Egyptian papyri from the first 3 centuries of Roman rule and interprets the results in economic terms. While nominal land values clearly increased, it is not possible to determine their growth rate relative to that of wheat prices. Recorded real land rentals clearly declined, however. It also appears that real wages declined over the same period. The best explanation for these changes is increasingly heavy taxation of output, later regularized under Diocletian.
The cost of diagnosing Helicobacter pylori infection

Non-invasive testing and treatment for Helicobacter pylori has been recommended for dyspeptic patients in primary care and a number of recent studies have demonstrated the cost-effectiveness of this approach. As the prevalence of H. pylori infection declines, the positive and negative predictive values of individual tests will change. Cost-effectiveness is important in determining the appropriate test in individual populations. Recent studies have shown that the stool antigen test and the urea breath test have high sensitivity and specificity in the detection of H. pylori infection before and after therapy. Cost-effectiveness studies have shown that when the prevalence of H. pylori infection is low or intermediate, serological tests have relatively poor accuracy compared with the stool test or the urea breath test. In populations with low or intermediate prevalence ( 60%), low-cost antibody tests are cost-effective.
The Measure of a Nation: The USDA and the Rise of Survey Methodology.

Abstract Survey research has played a major role in American social science. An outgrowth of efforts by the United States Department of Agriculture in the 1930s, the Division of Program Surveys (DPS) played an important role in the development of survey methodology. The DPS was headed by the ambitious and entrepreneurial Rensis Likert, populated by young and talented social scientists getting their first practical experience, and fed by the needs of the US government fighting World War II. The DPS innovations included open-ended interviewing and area probability sampling methodology as illustrated in the War Bond studies and the Master Sample of Agriculture. This paper examines the creation of the DPS, its work, and its legacy.
Influence of polymer characteristics and melt‐spinning conditions on the production of fine denier poly(ethylene terephtalate) fibers. Part III. Structure and properties of fine denier as‐spun PET fibers

The effect of decreasing take-up denier on the structure and mechanical properties of asspun poly(ethylene terephtalate) (PET) fibers is shown to be, in general, similar to an increase of take-up velocity. Both can be related to increased threadline cooling rate and increased spinline stress that control the structure development in the threadline. However, important distinctions were observed in the orientation and crystallization effects due to decrease of take-up denier or increase of take-up velocity. These distinctions were explained on the basis of the threadline dynamics study of the fine denier PET fiber in the high-speed spinning process, discussed in Part II of this study. Other properties, such as the dynamic mechanical properties and dye uptake, are not related to individual structure parameters, depending on the overall changes in structure, e.g., as given by the free volume.
Poverty in common: the politics of community action during the American century

Alyosha Goldstein's Poverty in Common examines the layers of ideology surrounding poverty in the mid- to late twentieth century US by addressing the interactions between the deployment of liberal p...
Regenerative medicine: self-directed articular resurfacing: a new paradigm?

Tissue engineering to repair diseased or injured cartilage could be revolutionized by the development of a novel cell-homing strategy that overcomes several barriers inherent in the use of existing techniques.
Complications Associated with Central Venous Catheters: A Survey

The Federal Food and Drug Administration has a system for reporting problems with medical devices that requires manufacturers of medical devices to report medical complications or equipment malfunction that causes, or could cause, death or serious injury. In a two-year period, central venous catheters were associated with 170 complications: tissue perforation, loss of catheter integrity, (including: catheter separation, severance, break, rip, puncture, or leak), and other problems. Causes of the complications were related to device failure (12 percent), health care professionals (55 percent), patients (3 percent), or pathologic or physiologic aspects (3 percent); causes of 28 percent of the complications were indeterminable. Further analysis indicated that complications (especially tissue perforation) were primarily health professional technique-related. There were no reports of complications related to infection. Data support the need for more education in catheter application and the need to modify the system by which these data are reported to more reliably detect infection. (Chest 1988; 94:1221-24)
Differential effects of the antidepressant mirtazapine on amphetamine- and dizocilpine-induced PPI deficits.

Abstract Prepulse inhibition (PPI) refers to the decrease in motor startle response to salient sensory stimuli (pulses) when they are closely preceded in time by another more modest sensory stimulus (prepulse). PPI deficits can be induced by stimulation of dopamine receptors (e.g., amphetamine or apomorphine) or blockade of NMDA glutamate receptors (e.g., dizocilpine or PCP). Previously we found that antagonists of α2-noradrenergic and H1-histaminergic receptors significantly attenuate PPI impairments caused by amphetamine or dizocilpine. In the current study we assessed the effects of the antidepressant mirtazapine, which has combined antagonist effects at α2-noradrenergic, H1-histaminergic and 5-HT serotonergic receptors, on amphetamine- and dizocilpine-induced PPI deficits. In Experiment 1, rats were tested for PPI of the startle response to a tactile air-puff stimulus after auditory prepulses of three different intensities. Drug treatments consisted of combinations of amphetamine (0 and 1 mg/kg) and mirtazapine (0, 0.5, 1, 2, and 5 mg/kg), with all rats receiving all drug doses and combinations with different counterbalanced orders. In Experiment 2, a different group of rats was tested with drug treatments consisting of combinations of dizocilpine (0 and 0.05 mg/kg) and mirtazapine (0, 0.5, 1, 2, and 5 mg/kg). In Experiment 1 amphetamine (1 mg/kg) significantly reduced PPI whereas mirtazapine caused the opposite effect, with the highest dose of mirtazapine (5 mg/kg) effectively reversing the amphetamine-induced PPI deficit. In Experiment 2 dizocilpine (0.05 mg/kg) significantly reduced PPI, but mirtazapine did not have a significant effect on the inhibition of the startle response. These results indicate that the potential beneficial effects of combined α-adrenergic, 5-HT, and H1 receptor blockade in counteracting PPI deficits may be associated to cases of sensorimotor gating disorders mediated by dopamine, but not necessarily to NMDA glutamate-induced PPI impairments.
Mechanism of mesenchymal stem cell-induced neuron recovery and anti-inflammation.

Abstract Background aims After ischemic or hemorrhagic stroke, neurons in the penumbra surrounding regions of irreversible injury are vulnerable to delayed but progressive damage as a result of ischemia and hemin-induced neurotoxicity. There is no effective treatment to rescue such dying neurons. Mesenchymal stem cells (MSCs) hold promise for rescue of these damaged neurons. In this study, we evaluated the efficacy and mechanism of MSC-induced neuro-regeneration and immune modulation. Methods Oxygen-glucose deprivation (OGD) was used in our study. M17 neuronal cells were subjected to OGD stress then followed by co-culture with MSCs. Rescue effects were evaluated using proliferation and apoptosis assays. Cytokine assay and quantitative polymerase chain reaction were used to explore the underlying mechanism. Antibody and small molecule blocking experiments were also performed to further understand the mechanism. Results We showed that M17 proliferation was significantly decreased and the rate of apoptosis increased after exposure to OGD. These effects could be alleviated via co-culture with MSCs. Tumor necrosis factor-α was found elevated after OGD stress and was back to normal levels after co-culture with MSCs. We believe these effects involve interleukin-6 and vascular endothelial growth factor signaling pathways. Discussion Our studies have shown that MSCs have anti-inflammatory properties and the capacity to rescue injured neurons.
Ethics and Genetic Testing

No discussion of genetic testing is complete without consideration of the ethical implications and anticipated societal ramifications. This challenging relationship between the science and the ethics of medical genetics is widely recognized and forms the basis for public concern over undergoing genetic testing. The central ethical tenants of autonomy, beneficence, nonmaleficence, and justice are discussed as they apply to the rapidly increasing availability of genetic testing. Specifically, the issues of informed consent, privacy, and genetic discrimination are described in their ethical context and illustrated with case presentations.
POLICE EMPLOYMENT AND SUBURBAN CRIME

Although politicians, police, and others have often advocated the expansion of police employment in the effort to control crime, the empirical relationship between police employment and crime rates has seldom been systematically explored. This study incorporates variables which are causally related both to crime and police employment roles for the 252 northern and northeastern suburbs for which police employment and crime data are available for 1970–1972. Separate analyses of violent and property crime are undertaken, incorporating data on police employment as a causally related variable along with several other determinants of crime identified in earlier studies. The analysis suggests that police employment and crime rates are reciprocally related, and that these relationships offer more support for a “labeling” than a “deterrence” perspective.
Attachment of substrate metabolite to prostaglandin H synthase upon reaction with arachidonic acid

Prostaglandin H synthase was incubated with [14C]arachidonate and then analyzed by polyacrylamide gel electrophoresis under denaturing conditions and by high pressure liquid chromatography. A maximum of 1 mol of arachidonate metabolite was found to become attached per mol of synthase subunit in a time-dependent process that was much slower than the rate of self-catalyzed inactivation of the cyclooxygenase activity. Incubation of a mixture of the synthase and ovalbumin with [14C]arachidonate resulted in a selective attachment of radiolabel to the synthase. These results suggest the presence of a single site on the synthase that is susceptible to reaction with an arachidonate metabolite.
Electronic stool subtraction using quadratic regression, morphological operations, and distance transforms

CT colonography (CTC) is being extensively studied for its potential value in colon examinations, since it offers many advantages such as lower risk and less patient discomfort. However, CTC, like all other types of full structural colorectal examinations to date, requires complete bowel preparation. The inconvenience and discomfort associated with this preparation is an important obstacle to compliance with currently recommended colorectal screening guidelines. To maximize compliance, CTC would ideally be performed on an unprepared colon. However, in an unprepared colon residual stool and fluid can mimic soft tissue density and thus confound the identification of polyps. An alternative is to tag the stool with an opacifying agent so that it is brighter than soft tissue and thus easily recognized automatically and then reset to air values. However, such electronic stool subtraction in a totally unprepared colon is difficult to perform accurately for several reasons, including poorly labeled areas of stool, the need to accurately quantify partial volume effects, and noise. In this study the qualitative performance of a novel stool subtraction algorithm was assessed in unprepared CT colonography screening exams of 26 consecutive volunteers. Results showed that nearly all stool was removed in 62% of the cases, fold erosion was mild or nonexistent in 75% of the cases, and wall erosion was mild or non-existent in 100% of cases. Although further study and refinement of the stool subtraction process is required, CT colonography of the unprepared colon with electronic stool subtraction is feasible.
Overexpression of glutathione reductase in cotton does not alter emergence rates under temperature stress.

Cotton (Gossypium hirsutum L.) seedlings are considered to be sensitive to temperature stress. The exposure of plants to high and low temperatures can result in the production of reactive oxygen species that contribute to diminished plant performance. Plants have mechanisms that metabolize oxidants into less harmful chemicals, and enhancement of antioxidant metabolism has been shown to be benefi cial to plants exposed to acute oxidative stresses. Transgenic overexpression of glutathione reductase (GR) in cotton could result in faster seedling emergence at nonoptimal temperatures. Transgenic GR and 5 nontransgenic cotton lines were planted at four dates in the fi eld in Lubbock, TX, and in constant temperature growth boxes. The temperatures in the fi eld were typical for the cotton planting period in the region, and in growth boxes ranged from 15 to 45°C. Emergence rates were determined for all lines, and the activity of GR and the levels of malondialdehyde in the cotyledons were monitored to verify altered enzyme activity and to detect differences in oxidative damage, respectively. Enhancement of GR activity did not improve emergence or reduce oxidative damage. It is concluded that GR activity did not limit emergence.
The Effect of the “Ohio Schools Going Solar” Project on Student Perceptions of the Quality of Learning in Middle School Science

AbstractIn an era of continuing developments in science and technology, teachers are faced with an increasingly challenging task of helping K–12 students become and remain scientifically literate. Effective science instruction involves activation of prior knowledge, hands-on learning, and continuous reflection. Technology has the potential to play a supporting role, and the Ohio Schools Going Solar project (OSGS) is one example of what is available. This study examines the effect of the OSGS project on student perceptions of the quality of science learning as defined by Newmann’s framework of authentic intellectual work. Results indicate a positive effect in the areas of disciplined inquiry and construction of knowledge.
Anomalous drag coupling between a thin superconducting film and a two-dimensional electron gas caused by radio frequency interference

We studied a bilayer system consisting of a two-dimensional electron gas in a $\mathrm{Ga}\mathrm{As}∕\mathrm{Al}\mathrm{Ga}\mathrm{As}$ heterostructure and a thin superconducting Al film. Drag measurements were made by passing current through the two-dimensional electron gas layer and measuring the voltage induced in the superconducting layer. Unexplained peaks in drag voltage near the transition region were seen in previous similar experiments. We also detected a draglike voltage peak in the transition region. The signal is found to be nonintrinsic and due to radio frequency interference. The extremely nonlinear impedance of the Al in the transition region allows the interference to couple in this manner. We show a simplified analysis of the measurement system that reproduces the main features of our results.
A GLOBAL–LOCAL INTEGRATED STUDY OF ROLLER CHAIN MESHING DYNAMICS

Abstract It has been recognized that one of the most significant noise sources in roller chain drives is from impacts between the chain and the sprocket during their meshing process. In this paper an analysis is presented which integrates the local meshing phenomena with the global chain/sprocket system dynamic behaviour. A coupled chain/sprocket system interacting with local impacts is modelled and the impulse function is derived. A study is carried out to quantify the intensity of subsequent impacts. It is found that the coupling effects between the sprockets, the chain spans, and the chain/sprocket meshing impulses increase with decreasing sprocket inertia and chain longitudinal stiffness. Experimental studies are also carried out to evaluate the meshing noise. It is found experimentally that the meshing sound pressure level is closely related to the chain speed and its vibrational characteristics, as predicted in the analytical study.
Photophysics of a Near IR Nonlinear Absorber for Waveguide Applications

Photophysics of a zinc porphyrin-based NIR nonlinear absorber are reported. Well-overlapped two-photon absorption and broad triplet excited state absorption result in a strong nonlinear optical response especially useful in waveguide applications.
One-Step Synthesis and Structure of an Oligo(spiro-orthocarbonate)

The reaction of pentaerythritol and tetraethylorthocarbonate at 260 °C for 12 h yields a white crystalline material that was characterized by 13C CPMAS NMR, CHN analysis, FT-IR, electron and X-ray powder diffraction, and Rietveld analysis. The white crystalline material was found to have the formula C6H8O4 and a crystal structure with a monoclinic cell [a = 9.167 A, b = 5.681 A, c = 5.880 A, β = 90.0°, space group I2] of hexagonally arranged spiro-oligomeric chains.
The origin of the blastemal cells in Dugesia tigrina

Abstract Neoblasts in planaria are not necessarily persistent embryonic stock, since they can be formed by dedifferentiation of specialized intestinal gland cells as well as by division of pre-existing neoblasts. This dedifferentiation is a continuous process in the normal, uninjured animal and in regenerating worms. In regenerating worms the relationship between the number of specialized intestinal gland cells and the number of embryonic cells at the peak of neoblast production is one of inverse proportion, i.e., as gland cells decrease in number, neoblasts increase. Mitosis in neoblasts cannot account for the large numbers of these cells in regenerating worms.
Asymmetric rostro-caudal inhibition in the primary olfactory cortex

The importance of intracortical inhibitory circuits in setting the feature-selective spatial organization of primary sensory cortices remains controversial. To address this issue, we examined the strength of interneuron-to-pyramidal cell connections across the rat anterior piriform cortex (aPC) and found a pronounced gradient of increasing pyramidal cell inhibition along the aPC rostro-caudal axis. This functional heterogeneity could govern aPC spatial activation in response to varying odor identities and features.
The effects of statistical fluctuations and perceived status of a competitor on the illusion of control in experienced gamblers

An experiment in gambling behavior was conducted under the most realistic conditions possible in our laboratory. Not only was there a significant monetary prize offered but subjects believed that they could be eliminated by a competitor. Subjects were 45 adults (25 females & 20 males; age range=23 to 73, mean age=51). Subjects were pitted in a gambling game against either a formidable or a vulnerable competitor. The competitor was a confederate playing one of the roles. The subjects either enjoyed a statistically favorable sequence of outcomes or suffered through a statistically negative sequence. In other words, they were made to lose badly, or made to win significantly. The object was to determine the effects of statistical fluctuations and the perceived status of a competitor on the illusion of control as measured by magnitude of risk taking. We hypothesized that we would see greater risks taken against a vulnerable competitor and during the favorable sequence, while lesser risks would be taken against a formidable competitor and an unfavorable sequence. However, neither variable was found to significantly effect the subjects on these measures. Unexpectedly, we identified a significant effect with respect to the number of wagers. It was found that subjects took significantly higher risks as a function of exposure to the gambling situation, without respect to conditions.
Post-herpetic neuralgia: possible mechanisms for pain relief with manual therapy.

This case report details the history, presentation, and treatment of a patient with a diagnosis of postherpetic neuralgia (PHN). The pathophysiology behind the development of PHN following infection with the varicella zoster virus (VZV) is discussed, although the exact mechanisms remain unclear. The subjective and objective findings in this patient with PHN are highlighted to alert other clinicians to the possibility of PHN as a differential diagnosis when patients attend the clinic for what they perceive to be pain of musculoskeletal origin. Following a description of the simple treatment approach that was adopted with this patient, possible mechanisms of action for this intervention are considered in relation to what is known of the underlying pathophysiology. However, it is not the author’s intention to propose manual therapy as a standard intervention for this condition.
A note on an assumption in the theory of cooperative phenomena

When the approximate methods of Bragg and Williams or Bethe are used in theoretical work on cooperative phenomena it is customary to suppose that only the configurational energy of the assembly depends on the molecular arrangement; the contribution which a molecule makes to the partition function, apart from its share in this configurational energy, is supposed to be independent of the positions of the other molecules.
Perfluorooctane sulfonate (PFOS) induces reactive oxygen species (ROS) production in human microvascular endothelial cells: role in endothelial permeability

Perfluorooctane sulfonate (PFOS) is a member of the perfluoroalkyl acids (PFAA) containing an eight-carbon backbone. PFOS is a man-made chemical with carbon-fluorine bonds that are among the strongest in organic chemistry, and PFOS is widely used in industry. Human occupational and environmental exposure to PFOS occurs globally. PFOS is non-biodegradable and is persistent in the human body and environment. In this study, data demonstrated that exposure of human microvascular endothelial cells (HMVEC) to PFOS induced the production of reactive oxygen species (ROS) at both high and low concentrations. Morphologically, it was found that exposure to PFOS induced actin filament remodeling and endothelial permeability changes in HMVEC. Furthermore, data demonstrated that the production of ROS plays a regulatory role in PFOS-induced actin filament remodeling and the increase in endothelial permeability. Our results indicate that the generation of ROS may play a role in PFOS-induced aberrations of the endothelial permeability barrier. The results generated from this study may provide a new insight into the potential adverse effects of PFOS exposure on humans at the cellular level.
Novel function of transcription factor Nrf2 as an inhibitor of RON tyrosine kinase receptor-mediated cancer cell invasion

Recepteur d' origine nantais (RON), a tyrosine kinase receptor, is aberrantly expressed in human tumors and promotes cancer cell invasion. RON receptor activation is also associated with resistance to tamoxifen treatment in breast cancer cells. Nrf2 is a positive regulator of cytoprotective genes. Using chromatin immunoprecipitation (ChIP) and site-directed mutagenesis studies of the RON promoter, we identified Nrf2 as a negative regulator of RON gene expression. High Nrf2 and low RON expression was observed in normal mammary tissue whereas high RON and low or undetectable expression of Nrf2 was observed in breast tumors. The Nrf2 inducer sulforaphane (SFN) as well as ectopic Nrf2 expression or knock-down of the Nrf2 negative regulator keap1, which stabilizes Nrf2, inhibited RON expression and invasion of carcinoma cells. Consequently, our studies identified a novel functional role for Nrf2 as a "repressor" and RON kinase as a molecular target of SFN, which mediates the anti-tumor effects of SFN. These results are not limited to breast cancer cells since the Nrf2 inducer SFN stabilized Nrf2 and inhibited RON expression in carcinoma cells from various tumor types.
Kinetochores: Orchestrating the Chromosomal Minuet

Summary When it comes to microtubules, kinetochores leave nothing to chance. Recent studies have provided insight into an amazingly choreographed dance between the proteins in the kinetochore and their substrate and power source — the microtubule.
Folate-Responsive Neurologic Diseases

Folate is a water-soluble vitamin of the B complex group, and is required for optimal health, growth, and development. In humans, it cannot be synthesized de novo. As a cofactor or coenzyme, folate plays key biological roles in a variety of physiologic processes: maintenance and repair of the genome, regulation of gene expression, amino-acid metabolism, neurotransmitter synthesis, and the formation of myelin. Dietary folates must undergo multiple, tightly regulated absorption and metabolic processes before their cellular utilization occurs. Clinical conditions associated with abnormal body folate status are very diverse. They range from genetic syndromes defined prior to conception, to malformations that develop during embryogenesis (neural tube defects), to disorders that are postnatally acquired and progressive (e.g., cerebral folate deficiency, or folinic acid-responsive seizures). Central nervous system folate deficiency or impaired availability can occur in the settings of normal or decreased systemic folate levels. Because the majority of patients respond to treatment with folinic acid, pediatric neurologists should remain vigilant to the possibility of deficiencies of folate in patients with unexplained neurologic disorders. The deleterious outcomes of untreated patients underscore the importance of making an early diagnosis.
STUDIES IN EDEMA II. THE INFLUENCE OF THE ADDITION OF ADRENALIN TO SOLUTIONS OF SODIUM CHLORIDE AND OF SODIUM CHLORIDE AND CALCIUM CHLORIDE SOLUTIONS AND OF A MORE RAPID RATE OF INFLOW UPON THE PRODUCTION OF URINE, ASCITES AND INTESTINAL FLUID.

1. In non-nephrectomized animals the addition of adrenalin to sodium chloride solutions or to mixtures of sodium chloride and calcium chloride solutions increases the amount of urine and of ascites, and diminishes the intestinal fluid (this diminution takes place only with mixtures of solutions of sodium chloride and calcium chloride, the quantity of intestinal fluid remaining approximately unchanged in the sodium chloride series). 2. In nephrectomized animals the addition of adrenalin to sodium chloride solutions or to mixtures of sodium chloride and calcium chloride solutions again increases the ascites and diminishes the amount of intestinal fluid in both sodium chloride and sodium chloride plus calcium chloride series. 3. We find, therefore, a summation of the action of calcium chloride and adrenalin in regard to their influence upon the formation of ascites, an antagonistic action in regard to the elimination of urine; here the influence of calcium chloride in diminishing the urine is more potent than is the action of adrenalin in increasing the amount of urine. The adrenalin decreases the elimination of fluid into the intestines and in this case we note a summation of the actions of calcium chloride and of adrenalin. 4. We see, therefore, that adrenalin and calcium chloride influence the amount of ascitic fluid and of intestinal fluid in the same direction. The amount of urine is, however, decreased by calcium chloride and increased by adrenalin. 5. If we increase the rapidity of inflow of the solutions and simultaneously decrease proportionately the time of the infusion, the amount of ascites and intestinal fluids in nephrectomized animals remains approximately unchanged, as compared with the amounts obtained at the usual rate of inflow.
Mastering the challenge of optoelectronic computing

We discuss the research on optoelectronic computing systems that is being conducted in one of the National Science Foundation's (NSF) Engineering Research Centers. The center, now in its sixth year as a NSF Engineering Research Center, is located at the University of Colorado in Boulder and Colorado State University in Fon Collins. We focus on the contributions that an Engineering Research Center can make to research, education. and technology transfer because of its interdisciplinary nature, its focus on systems, and its involvement with industries active in the field of interest to the Center. We describe the mission, vision. the research goals, and the structure of the Optoelectronic Computing Systems Center to demonstrate how the Center provides a powerful cross·disciplinary framework within which to conduct important research in the field of optoelectronic computing. Several unique research issues that are being pursued at the Center are discussed. Examples of these issues are new neural network algorithms that are specifically tailored to the application of optics in the design of neural network computing machines, speed·of.light digital computer architectures in which the infonnation is in constant motion and is never static or stored in a latching memory, and ferroelectric liquid crystal materials that are tailored for use in spatial light modulators and optoelectronic neural computing systems. The paper also explores the impact of the Center on education at the two universities.
Assembly of lampbrush chromosomes from sperm chromatin.

We have examined the behavior of demembranated sperm heads when injected into the germinal vesicle (GV) of amphibian oocytes. Xenopus sperm heads injected into Xenopus GVs swelled immediately and within hours began to stain with an antibody against RNA polymerase II (Pol II). Over time each sperm head became a loose mass of chromosome-like threads, which by 24–48 h resolved into individually recognizable lampbrush chromosomes (LBCs). Although LBCs derived from sperm are unreplicated single chromatids, their morphology and immunofluorescent staining properties were strikingly similar to those of the endogenous lampbrush bivalents. They displayed typical transcriptionally active loops extending from an axis of condensed chromomeres, as well as locus-specific “landmarks.” Experiments with [3H]GTP and actinomycin D demonstrated that transcription was not necessary for the initial swelling of the sperm heads and acquisition of Pol II but was required for maintenance of the lampbrush loops. Splicing was not required at any stage during formation of sperm LBCs. When Xenopus sperm heads were injected into GVs of the newt Notophthalmus, the resulting sperm LBCs displayed very long loops with pronounced Pol II axes, like those of the endogenous newt LBCs; as expected, they stained with antibodies against newt-specific proteins. Other heterologous injections, including sperm heads of the frog Rana pipiens and the zebrafish Danio rerio in Xenopus GVs, confirm that LBCs can be derived from taxonomically distant organisms. The GV system should help identify both cis- and trans-acting factors needed to convert condensed chromatin into transcriptionally active LBCs. It may also be useful in producing cytologically analyzable chromosomes from organisms whose oocytes do not go through a typical lampbrush phase or cannot be manipulated by current techniques.
A direct test of cyanobacterial chemical defense: Variable effects of microcystin‐treated food on two Daphnia pulicaria clones

To determine the direct effects of microcystin on the fitness of herbivorous zooplankton, we experimentally added microcystin-LR to freeze-dried cells of palatable Chlorella and fed these compound-treated cells to two clones of Daphnia pulicaria that had shown differing responses to a diet containing a strain of Microcystis aeruginosa that produces microcystin. The Daphnia that performed better on a diet containing live Microcystis showed reduced population growth when exposed to microcystin-LR-treated Chlorella, whereas the Daphnia that performed poorly on the diet containing live Microcystis was not affected by the experimental diet containing microcystin-LR. This is the first study to unambiguously show that some Daphnia strains are and some strains are not harmed by the consumption of microcystin-LR. These surprising results were not generated by interference from lipophilic secondary metabolites in Microcystis. When the crude lipophilic extract of Microcystis was added to dried Chlorella cells, it enhanced the fitness of both Daphnia clones. We hypothesize that the Daphnia clone more tolerant to live cells may upregulate resistance when cued by the presence of the live Microcystis cells, but not by microcystin-LR alone. Alternatively, the Daphnia clone that grew well on a diet containing live Microcystis may sequester compounds from Microcystis that defend the cyanobacteria from autotoxicity; these compounds would have been unavailable to Daphnia consuming freeze-dried Chlorella treated with microcystin-LR alone. Thus, microcystin-LR can suppress Daphnia fitness when consumed; however, the effects of microcystin vary across clones of herbivorous zooplankton and the consequences of this variance should not be overlooked when considering zooplankton-cyanobacteria interactions.
Meat intake and semen parameters among men attending a fertility clinic

M. Afeiche, A. Gaskins, T. Toth, C. Tanrikut, R. Hauser, J. Chavarro. Department of Nutrition, Harvard School of Public Health, Boston, MA; Vincent Memorial Obstetrics and Gynecology Service, Massachusetts General Hospital and Harvard Medical School, Boston, MA; Department of Urology, Massachusetts General Hospital and Harvard Medical School, Boston, MA; Department of Environmental Health, Harvard School of Public Health, Boston, MA.
A RF to DC Voltage Conversion Model for Multi-Stage Rectifiers in UHF RFID Transponders

This paper presents a RF to DC conversion model for multi-stage rectifiers in UHF RFID transponders. An equation relating the RF power available from the antenna to the DC output voltage produced by a multi-stage rectifier is presented. The proposed model includes effects of the nonlinear forward voltage drop in diodes and impedance matching conditions of the antenna to rectifier interface. Fundamental frequency impedance approximation is used to analyze the resistance of rectifying diodes; parasitic resistive loss components are also included in the analysis of rectifier input resistance. The closed form equation shows insights into design parameter tradeoffs, such as power available from the antenna, antenna radiation resistance, the number of diodes, DC load current, parasitic resistive loss components, diode and capacitor sizes, and frequency of operation. Therefore, it enables the optimization of rectifier parameters for impedance matching with a low-cost printed antenna and shunt tuning inductor, in order to improve the RF to DC conversion efficiency and the operational distance of UHF RFID transponders. Three diode doublers and three multistage rectifiers were fabricated in a 130 nm CMOS process with custom no-mask added Schottky diodes. Measurements of the test IC are in good agreement with the proposed model.
P2P video synchronization in a collaborative virtual environment

We previously developed a collaborative virtual environment (CVE) for small-group virtual classrooms, intended for distance learning by geographically dispersed students. The CVE employs a P2P approach to the frequent real-time updates to the 3D virtual worlds required by avatar movements (fellow students in the same room). This paper focuses on our extensions to support group viewing of lecture videos, called VECTORS, for Video Enhanced Collaboration for Team Oriented Remote Synchronization. VECTORS supports synchronized viewing of lecture videos, so the students all see “the same thing at the same time”, and can pause, rewind, etc. in synchrony while discussing the lecture via “chat”. We are particularly concerned with the needs of the technologically disenfranchised, e.g., whose only Internet access if via dialup networking. Thus VECTORS employs semantically compressed videos with meager bandwidth requirements.
The structure of high-temperature solar flare plasma in non-thermal flare models

Analytic differential emission measure distributions have been derived for coronal plasma in flare loops heated both by collisions of high-energy suprathermal electrons with background plasma, and by ohmic heating by the beam-normalizing return current. For low densities, reverse current heating predominates, while for higher densities collisional heating predominates. There is thus a minimum peak temperature in an electron-heated loop. In contrast to previous approximate analyses, it is found that a stable reverse current can dominate the heating rate in a flare loop, especially in the low corona. Two 'scaling laws' are found which relate the peak temperature in the loop to the suprathermal electron flux. These laws are testable observationally and constitute a new diagnostic procedure for examining modes of energy transport in flaring loops.
"Lessons learned from autism: a parent's perspective".

A parent and professor of clinical pediatrics shares her experience of parenting a child with autism.
The Role of Carbohydrate Metabolism in the Regulation of Postfeeding Diuresis in Adult Helicoverpa zea (Lepidoptera: Noctuidae)

The effects of hemolymph sugar levels and carbohydrate metabolism on postfeeding diuresis in corn earworm moths, Helicoverpa zea (Boddie) were examined. High levels of ingested sucrose or the ingestion of nonmetabolizable sugars resulted in a reduced rate of diuresis. The magnitude of postfeeding diuresis appears to be dependent on the ability of the moth to metabolize ingested sugar after it has been passed to the hemolymph. Glycogen synthase (GS) and trehalose-6-phosphate synthase (TS) can reverse the increase in hemolymph osmolarity that accompanies sucrose digestion by the conversion of glucose to glycogen and trehalose. The level of fat body GS/TS activity correlates with differences in postfeeding diuresis between males and females and with changes in the magnitude of diuresis as moths age. These data suggest that the magnitude of postfeeding diuresis may ultimately depend on the enzymatic activities that control hemolymph sugar levels.
Calculation of mutual inductance from magnetic vector potential for wireless power transfer applications

Recent renewed interest in commercial development of wireless power transfer through magnetically-coupled resonant circuits has shown the need for a computational tool that can calculate the mutual inductance of coils of arbitrary geometry and spatial orientation. This task is often performed by finite-element analysis (FEA), but this requires both access to such software and a degree of expertise on the part of the designer. This paper introduces a simple-to-use Matlab-based computational tool for calculating mutual inductance for inductors in free space based upon magnetic vector potential.
Cobalamin Used in Chronic Fatigue Syndrome Therapy Is a Nitric Oxide Scavenger

ABSTRACTCobalamin (vitamin B12) in the form of hydroxocobalamin or cyanocobalamin injections has been widely used to treat chronic fatigue syndrome (CFS). Hydroxocobalamin is a nitric oxide scavenger and is proposed here to act as such a scavenger in CFS treatment. Its possible efficacy in CFS treatment, if further substantiated, may provide confirmation of a prediction of the elevated nitric oxide/peroxynitrite theory of CFS etiology. This interpretation of the possible role of cobalamin in CFS treatment suggests a useful perspective for confirming and optimizing this treatment.