cssi/SciSciGPT-SciSciNet huggingface dataset:
Ribavirin mitigates wart growth in rabbits at early stages of infection with cottontail rabbit papillomavirus

The challenge to develop antiviral agents effective against DNA viruses such as human papillomavirus (HPV) has been dependent on finding an animal model which mimics the human forms of the disease. We have used an existing model system for the purpose of measuring the effect of antiviral drugs on the inhibition of growth of these lesions. This was based upon domestic rabbits which efficiently grow cutaneous papillomas (warts) when infected with cottontail rabbit papillomavirus (CRPV). One agent which had shown significant success in achieving these goals was ribavirin. Ribavirin was administered intradermally shortly prior to infection at multiple sites with CRPV. Following daily injections of this drug for eight weeks, we have shown a dose-dependent response which had markedly reduced the number of warts, the time of first appearance of warts and reduced the tumor mass as compared to placebo-treated control animals. At the highest dose of ribavirin tested, 30 mg/kg/day, compared to controls, the average reduction in the number of warts was 52%, the average time of first appearance of warts was 49% longer, and the average mass of the warts was reduced by 98%. No detectable antibodies to CRPV were observed in any of the animals. The only side effects which were observed was focal alopecia, and a decrease in body growth upon prolonged treatment, both of which were completely reversible. Pharmacokinetic studies established the metabolism of ribavirin over a 24-h period of time. Ribavirin administered beginning 12 or 30 days post-infection, while not reducing the number of warts, slightly retarded the growth of warts as determined by date of first appearance of warts and mass of warts.
Effective boundary conditions for the Laplace equation with a rough boundary

The problem of replacing Dirichlet or Neumann conditions on a stochastically embossed surface by approximate effective conditions on a smooth surface is studied for potential fields satisfying the Laplace equation. A combination of ensemble averaging and multiple-scattering techniques is used. It is shown that for the Dirichlet case the effective boundary condition becomes mixed and establishes a relation between the averaged field and its normal derivative. For the Neumann problem the normal derivative on the smooth surface equals a suitable combination of first- and second-order derivatives tangent to the surface. Explicit results are given for small boss concentration and illustrated with the examples of spheroidal and spherical bosses. For the Dirichlet case with hemispherical bosses, direct numerical-simulation results are presented up to area coverages of 75%. An application of the results to the calculation of the added mass of a rough sphere in potential flow, of the capacitance of a rough spherical conductor, and of the transmission and reflection of long water waves at a smooth-rough bottom transition aids in their physical interpretation.
Design of a wireless footswitch for medical applications

A wireless communication system was designed to replace the umbilical wiring of the footswitch of the UroView™ system manufactured by GE Healthcare®. This wireless system consists of a transmitter and a receiver that allows the user to operate the footswitch at a distance less than 20 yards, and through 4 inches of lead. The device complies with UL 60601-1 international standards. The Microchip® rfPIC12F675K™ was selected for transmission, and the Microchip® rfRXDO420™ was selected for reception. Using Keeloq® technology, the system is capable of secure transmission that helps to eliminate any false triggering of the UroView™ device. The communication system was included into the existing hardware of the UroView™ using Altera® Field Programmable Gate Arrays, that were programmed using Verilog design technology. The fully functioning wireless footswitch can be used to control the GE UroView™ system and can also act as a stepping stone to help convert other GE Healthcare® devices to communicate wirelessly in the future.
The rôle of the antennae and compound eyes of the moth Heliothis zea in attraction to light

Abstract The relative role of the compound eye and antennae of Heliothis zea in the attraction to light was determined in a behavioural experiment. The response was measured by releasing tethered insects at selected angles to an incandescent lamp. By disabling the eye and antennae in various combinations, we conclude that the eyes are the only sensory detectors which mediate the attraction to light. Inhibitory signals which lower the level of attraction to light originate in the flagella.
TFBSshape: a motif database for DNA shape features of transcription factor binding sites

Transcription factor binding sites (TFBSs) are most commonly characterized by the nucleotide preferences at each position of the DNA target. Whereas these sequence motifs are quite accurate descriptions of DNA binding specificities of transcription factors (TFs), proteins recognize DNA as a three-dimensional object. DNA structural features refine the description of TF binding specificities and provide mechanistic insights into protein-DNA recognition. Existing motif databases contain extensive nucleotide sequences identified in binding experiments based on their selection by a TF. To utilize DNA shape information when analysing the DNA binding specificities of TFs, we developed a new tool, the TFBSshape database (available at http://rohslab.cmb.usc.edu/TFBSshape/), for calculating DNA structural features from nucleotide sequences provided by motif databases. The TFBSshape database can be used to generate heat maps and quantitative data for DNA structural features (i.e., minor groove width, roll, propeller twist and helix twist) for 739 TF datasets from 23 different species derived from the motif databases JASPAR and UniPROBE. As demonstrated for the basic helix-loop-helix and homeodomain TF families, our TFBSshape database can be used to compare, qualitatively and quantitatively, the DNA binding specificities of closely related TFs and, thus, uncover differential DNA binding specificities that are not apparent from nucleotide sequence alone.
Weak solution for the Hele-Shaw problem: Viscous shocks and singularities

In Hele-Shaw flows, a boundary of a viscous fluid develops unstable fingering patterns. At vanishing surface tension, fingers evolve to cusp-like singularities preventing a smooth flow. We show that the Hele-Shaw problem admits a weak solution where a singularity triggers viscous shocks. Shocks form a growing, branching tree of a line distribution of vorticity where pressure has a finite discontinuity. A condition that the flow remains curl-free at a macroscale uniquely determines the shock graph structure. We present a self-similar solution describing shocks emerging from a generic (2, 3)-cusp singularity—an elementary branching event of a branching shock graph.
Ultrastructural localization of gamma amino butyric acid immunoreactivity in B cells of the rat pancreas

The purpose of this study was to determine the ultrastructural localization of gamma amino butyric acid (GABA) within the B cell of isolated rat islets, particularly with respect to the B cell secretion granules. GABA immunoreactivity was localized ultrastructurally, with colloidal gold, in the B cells and absent in the A cells and D cells. Quantitative analysis of the colloidal gold particle distribution in the B cell revealed 29.5 +/- 5.2 gold particles/micron 2 in the nuclei, 29.3 +/- -6.9 gold particles/micron 2 in the mitochondria and 4.9 +/- 1.0 gold particles/micron 2 in the secretion granules. Particle density in the remainder of the cytoplasm was 41.9 +/- 4.1 particles/micron 2. The paucity of gamma amino butyric acid in the B cell secretion granules differs from observations on gamma amino butyric acidergic neurons, where there is an accumulation of gamma amino butyric acid within the neurosecretory vesicles. These findings indicate that if gamma amino butyric acid is released from the islet, then it is by a nongranular mechanism. In addition, the results are compatible with the hypotheses that gamma amino butyric acid within the B cell functions in the regulation of insulin biosynthesis, and/or functions as an alternative energy source for the B cell through the gamma amino butyric acid shunt.
Comparison of Stresses in Center-Wound Rolls From Two Linear Elastic Models

wound rolls. Burns et al. WOS solution for roll stresses was recently developed; the analysis converted the accreted residual, wound on strains from the web into an elastic boundary value problem which yielded the stresses in the roll. Altmann developed his displacement based intralayer accretion solution by balancing forces for a thin cylindrical shell clamped onto a roll as a stressed layer in the roll. His COS model has been the basis for most linear and nonlinear analyses on this topic, @ 4‐1 0#. The WOS and COS analyses are formulated in stress and strain, respectively. The WOS and COS solutions were thought to be compatible since both analyses are based on the same deformation formulas and adaptations of Hooke’s law. The stresses in center-wound rolls for assumed linear elastic media should be the same since both models describe the same problem. In the linear elastic limit, they were initially thought to be identical, i.e., elastic solutions. We show here in the linear elastic limit, differences between the models. Moreover, stresses in center-wound rolls are well known to be more complex as the media is both nonlinear and nonelastic. COS and WOS differences should be clarified before undertaking the complications of a realistic constitutive law for nonlinear, nonelastic stacked sheets. Hakiel @5# and Benson @6# have nonlinear, nonanalytic solutions for the wound roll problem. Hakiel uses the same boundary conditions as the COS model while Benson utilizes a method which allows the outer lap to relax. The linear elastic differences between the COS and WOS models are as large as the nonlinear media effects are on accreting layers. If the COS model does not provide a good description of roll stresses then subsequent nonlinear work based on this model are suspect. This paper discusses how the inclusion of residual strains into the elastic solution compares with the inclusion of a clamped on stress boundary condition.
Prospects of gigascale integration (GSI) beyond 2003

The authors suggest that beyond 2003, further opportunities for GSI will be governed by a hierarchy of theoretical and practical limits whose levels can be codified as: (1) fundamental, (2) material, (3) device, (4) circuit, and (5) system. Theoretical limits are elucidated by plotting the average power dissipation during a binary switching transition of a logic gate P versus the corresponding gate delay time t/sub d/ and the reciprocal length squared of an interconnect versus the response time of the interconnect circuit. Using both the hierarchy of theoretical limits and the history of practical limits as guides, a one-billion-transistor chip is again projected by the year 2000 and the possibility of a one-trillion-transistor chip by the year 2020 is suggested. >
Supernova 1954J (Variable 12) in NGC 2403 Unmasked

We have confirmed that the precursor star of the unusual supernova 1954J (also known as Variable 12) in NGC 2403 survived what appears to have been a superoutburst, similar to the 1843 Great Eruption of η Carinae in the Galaxy. The apparent survivor has changed little in brightness and color over the last 8 years, and a Keck spectrum reveals characteristics broadly similar to those of η Car. This is further suggested by our identification of the actual outburst-surviving star in high-resolution images obtained with the Advanced Camera for Surveys on the Hubble Space Telescope. We reveal this "supernova impostor" as a highly luminous ( mag), very massive (Minitial 25 M⊙) eruptive star, now surrounded by a dusty (AV ≈ 4 mag) nebula, similar to η Car's famous Homunculus.
A Comparison of Two Methods of Test Equating in the Rasch Model.

Two approaches to equating, the common item equating method (weighted and unweighted) and the one-step, missing data calibration method, used with Rasch (1960/1980) measurement models are compared. The data used in the analysis were taken from six equivalent forms of a perceptual ability test administered as part of the Dental Admission Test. Simulated data patterned after the observed item difficulties were also analyzed to form a frame of reference against which to judge the accuracy of the equating. The results indicate that there is very little difference among the three methods of equating even in the presence of measurement disturbances such as guessing.
Computational analysis of type II endoleaks in a stented abdominal aortic aneurysm model

Insertion of a stent-graft into an aneurysm to form a new (synthetic) blood vessel and prevent the weakened artery wall from rupture is an attractive surgical intervention when compared to traditional open surgery. However, focusing on a stented abdominal aortic aneurysm (AAA), post-operative complications such as endoleaks may occur. An endoleak is the net influx of blood during the cardiac cycle into the cavity (or sac) formed by the stent-graft and the AAA wall. A natural endoleak source may stem from one or two secondary branches leading to and from the aneurysm, labeled types IIa and IIb endoleaks. Employing experimentally validated fluid-structure interaction solvers, the transient 3-D lumen and cavity blood flows, wall movements, pressure variations, maximum wall stresses and migration forces were computed for types IIa and IIb endoleaks. Simulation results indicate that the sac pressure caused by these endoleaks depends largely on the inlet branch pressure, where the branch inlet pressure increases, the sac pressure may reach the systemic level and AAA-rupture is possible. The maximum wall stress is typically located near the anterior-distal side in this model, while the maximum stent-graft stress occurs near the bifurcating point, in both cases, due to local stress concentrations. The time-varying leakage rate depends on the pressure difference between AAA sac and inlet branch. In contrast, the stent-graft migration force is reduced by type II endoleaks because it greatly depends on the pressure difference between the stent-graft and the aneurysm cavity.
Where Does Mediator Bind In Vivo

Background The Mediator complex associates with RNA polymerase (Pol) II, and it is recruited to enhancer regions by activator proteins under appropriate environmental conditions. However, the issue of Mediator association in yeast cells is controversial. Under optimal growth conditions (YPD medium), we were unable to detect Mediator at essentially any S. cerevisiae promoter region, including those supporting very high levels of transcription. In contrast, whole genome microarray experiments in synthetic complete (SC) medium reported that Mediator associates with many genes at both promoter and coding regions. Principal Findings As assayed by chromatin immunoprecipitation, we show that there are a small number of Mediator targets in SC medium that are not observed in YPD medium. However, most Mediator targets identified in the genome-wide analysis are false positives that arose for several interrelated reasons: the use of overly lenient cut-offs; artifactual differences in apparent IP efficiencies among different genomic regions in the untagged strain; low fold-enrichments making it difficult to distinguish true Mediator targets from false positives that occur in the absence of the tagged Mediator protein. Lastly, apparent Mediator association in highly active coding regions is due to a non-specific effect on accessibility due to the lack of nucleosomes, not to a specific association of Mediator. Conclusions These results indicate that Mediator does not bind to numerous sites in the yeast genome, but rather selectively associates with a limited number of upstream promoter regions in an activator- and stress-specific manner.
Sugar-derived glasses support thermal and photo-initiated electron transfer processes over macroscopic distances

Trehalose-derived glasses are shown to support long range electron transfer reactions between spatially well separated donors and protein acceptors. The results indicate that these matrices can be used not only to greatly stabilize protein structures but also to facilitate both thermal and photo-initiated hemeprotein reduction over large macroscopic distances. To date the promise of exciting new protein-based technologies that can harness the exceptional tunability of protein functionality has been significantly thwarted by both intrinsic instability and stringent solvent/environment requirements for the expression of functional properties. The presented results raise the prospect of overcoming these limitations with respect to incorporating redox active proteins into solid state devices such as tunable batteries, switches, and solar cells. The findings also have implications for formulations intended to enhance long term storage of biomaterials, new protein-based synthetic strategies, and biophysical studies of functional intermediates trapped under nonequilibrium conditions. In addition, the study shows that certain sugars such as glucose or tagatose, when added to redox-inactive glassy matrices, can be used as a source of thermal electrons that can be harvested by suitable redox active proteins, raising the prospect of using common sugars as an electron source in solid state thermal fuel cells.
The Influence of Academic and Environmental Factors on Hispanic College Degree Attainment

This study used the NELS 88‑2000 data base to examine among Hispanic students precollege, college, and environmental predictors of (a) college first enrolled in (two‑year versus four‑year) and (b) undergraduate degree attainment for students who first enrolled in a two‑year or four‑year college. Hispanic students who attended a four-year college right after high school were much more likely to obtain a bachelor's degree than their peers who first attended a community college. Furthermore, precollege variables were more salient in predicting bachelor degree attainment for students who started in two‑year colleges, while college-related variables were more salient for students who started in four‑year colleges.
Nerve grafts are rarely necessary and are unlikely to improve sexual function in men undergoing anatomic radical prostatectomy.

H often is it necessary to excise one or both neurovascular bundles widely at the time of radical prostatectomy and is it useful to use an interposition nerve graft in an attempt to restore sexual function in these patients? In this essay, I express my opinion about when it is necessary to excise the neurovascular bundles, how often potency recovers in patients with unilateral wide excision, and what is the value of nerve grafts.
B-cell lymphoma 6 and the molecular pathogenesis of diffuse large B-cell lymphoma.

Purpose of review The B-cell lymphoma 6 transcriptional repressor is the most commonly involved oncogene in B-cell lymphomas. Sustained expression of B-cell lymphoma 6 causes malignant transformation of germinal center B cells. Understanding the mechanism of action of B-cell lymphoma 6 is crucial for the study of how aberrant transcriptional programming leads to lymphomagenesis and development of targeted antilymphoma therapy. Recent findings Identification of B-cell lymphoma 6 target genes indicates a critical role for B-cell lymphoma 6 in facilitating a state of physiological genomic instability required for germinal center B cells to undergo affinity maturation, and suggests its contribution to several additional cellular functions. The discovery of several layers of counterregulatory mechanisms reveals how B cells can control and fine-tune the potentially lymphomagenic actions of B-cell lymphoma 6. From the biochemical standpoint, B-cell lymphoma 6 can regulate distinct biological pathways through different cofactors. This observation explains how the biological actions of B-cell lymphoma 6 can be physiologically controlled through separate mechanisms and affords the means for improved therapeutic targeting. The fact that patients with B-cell lymphoma 6-dependent lymphoma can be identified on the basis of gene signatures suggests that therapeutic trials of B-cell lymphoma 6 inhibitors could be personalized to these individuals. Summary B-cell lymphoma 6 plays a fundamental role in lymphomagenesis and is an excellent therapeutic target for development of improved antilymphoma therapeutic regimens.
The Use of Evidence-Based Practices in Substance Abuse Treatment Programs

Abstract Several forces have converged to encourage the use of evidence-based practices (EBP) in the substance abuse treatment field. These influences include managed care organizations, state and federal funding agencies, credentialing bodies, state Medicaid programs and consumer groups. Their shared goal is to allocate limited resources to treatment organizations that provide clinically effective treatment to individuals with substance use disorders. A recent study evaluated the use of EBP in outpatient substance abuse (OPSA) programs in the six New England states. Findings suggest that there is limited use of EBP in OPSA programs as measured by their utilization of screening and assessment tools, patient placement criteria (PPC) and practice guidelines. Implications for OPSA treatment programs are discussed.
Are trauma patients better off in a trauma ICU

There is very little data on the value of specialized intensive care unit (ICU) care in the literature. To determine if specialize ICU care for the trauma patient improved outcomes in this patient population. Level I Trauma Center Compared outcomes of trauma patients treated in a surgical trauma ICU (STICU) to those treated in non- trauma ICUs (non-STICU). Retrospective review of trauma registry data. Statistical Analysis: Wilcoxon Rank Test , Fischer's Exact test, logistic regression. There were 1146 STICU patients compared to 1475 non-STICU. In all ISS groups there were more penetrating trauma patients in the STICU (32.54% STICU vs. 18.15% non-STICU, P 25)). All groups had similar lengths of stay. The blunt trauma patients were sicker in the STICU (20.8 ISS ± 12.2 STICU vs. 19.7 ISS ± 11.9 non-STICU, P =0.03) yet had similar outcomes to the non-STICU group. Logistic regression identified penetrating trauma and not ICU location as a predictor of mortality. Sicker STICU patients do as well as less injured non-STICU patients. Severely injured patients should be preferentially treated in a STICU where they are better equipped to care for the complex multi-trauma patient. All patients, regardless of location, do well when their management is guided by a surgical critical care team.
On a problem of Duke--Erdős--Rödl on cycle-connected subgraphs

In this short note, we prove that for @b<1/5 every graph G with n vertices and n^2^-^@b edges contains a subgraph G^' with at least cn^2^-^2^@b edges such that every pair of edges in G^' lie together on a cycle of length at most 8. Moreover edges in G^' which share a vertex lie together on a cycle of length at most 6. This result is best possible up to the constant factor and settles a conjecture of Duke, Erdos, and Rodl.
Migration and the quasi-labor market in Russia.

This paper explores the twin concepts of labor demand and labor mobility during the Soviet and post-Soviet periods. The study uses a detailed data set on labor stock, industrial labor demand, and labor flows for the 1980s in the Yaroslavl Oblast, and data on migration and regional labor markets for all Russian regions in the 1990s. Contextual features, such as the social contract, full employment, methods of labor allocation, and a generally low rate of geographic mobility, distinguish the centrally planned quasi-labor market from the labor market in capitalist democracies. The findings suggest that net in-migration induces employment change in the current period rather than in a future period. The job creation effects appear concurrent with migration during the Soviet period. In the post-Soviet period, migration and employment relationships are not predictable based on the same relationships during the Soviet period.
A Classifier to Evaluate Language Specificity of Medical Documents

Consumer health information written by health care professionals is often inaccessible to the consumers it is written for. Traditional readability formulas examine syntactic features like sentence length and number of syllables, ignoring the target audience's grasp of the words themselves. The use of specialized vocabulary disrupts the understanding of patients with low reading skills, causing a decrease in comprehension. A naive Bayes classifier for three levels of increasing medical terminology specificity (consumer/patient, novice health learner, medical professional) was created with a lexicon generated from a representative medical corpus. Ninety-six percent accuracy in classification was attained. The classifier was then applied to existing consumer health Web pages. We found that only 4% of pages were classified at a layperson level, regardless of the Flesch reading ease scores, while the remaining pages were at the level of medical professionals. This indicates that consumer health Web pages are not using appropriate language for their target audience
Assessing plant growth, water quality and economic effects from application of a plant-based aquafeed in a recirculating aquaponic system

Aquaponics, the integrated production of fish and hydroponic crops in a recirculating system, is an intensive cultivation method in which metabolic fish wastes fertilize plants. This study compares the effects of two aquafeeds on Red amaranth (Amaranthus tricolor) productivity and on water quality parameters under cultivation of Blue tilapia (Oreochromis aureus), in three aquaponic replicate units per treatment over a 60-day experimental trial. The fishmeal-based control feed contains higher crude protein (40 %) and phosphorus (1.12 %) than the plant-based alternative feed (32 % and 0.40 %, respectively). The alternative feed resulted in a significantly higher amaranth crop yield (p < 0.05), with significantly lower concentrations of nitrate-N (NO3-N) and total dissolved solids (TDS) in the aquaponic culture water over the course of the experiment. Orthophosphate (PO4-P), total ammonia nitrogen (TAN), pH and dissolved oxygen (DO) levels were not significantly different between the control and alternative aquafeed treatments. Economic analysis revealed that improved plant productivity from the plant-based, lower-protein aquafeed may potentially increase total aquaponic farm revenue despite reduced fish production.
Considerations for selection and use of computers in the university engineering environment

The authors report on the selection and use of several computer systems at Louisiana Tech University. They describe the purchase decision, installation, and subsequent use of a Sun network, an HP network, a PS/2 LAN (local area network), a Macintosh network, and a PC Novell network. Operating systems (DOS, Multifinder, and Unix) and software application programs are discussed. >
SENIC: scalable NIC for end-host rate limiting

Rate limiting is an important primitive for managing server network resources. Unfortunately, software-based rate limiting suffers from limited accuracy and high CPU overhead, and modern NICs only support a handful of rate limiters. We present SENIC, a NIC design that can natively support 10s of thousands of rate limiters--100x to 1000x the number available in NICs today. The key idea is that the host CPU only classifies packets, enqueues them in per-class queues in host memory, and specifies rate limits for each traffic class. On the NIC, SENIC maintains class metadata, computes the transmit schedule, and only pulls packets from host memory when they are ready to be transmitted (on a real time basis). We implemented SENIC on NetFPGA, with 1000 rate limiters requiring just 30KB SRAM, and it was able to accurately pace packets. Further, in a memcached benchmark against software rate limiters, SENIC is able to sustain up to 250% higher load, while simultaneously keeping tail latency under 4ms at 90% network utilization.
Seismic parameters controlling far-field tsunami amplitudes: A review

We present a review of the influence of various parameters of the sources of major oceanic earthquakes on the amplitude of tsunamis at transoceanic distances. We base our computations on the normal mode formalism, applied to realistic Earth models, but interpret our principal results in the simpler framework of Haskell theory in the case of a water layer over a Poisson half-space. Our results show that source depth and focal geometry play only a limited role in controlling the amplitude of the tsunami; their combined influence reaches at most 1 order of magnitude down to a depth of 150 km into the hard rock. More important are the effects of directivity due to rupture propagation along the fault, which for large earthquakes can result in a ten-fold decrease in tsunami amplitude by destructive interference, and the possibility of enhanced tsunami excitation in material with weaker elastic properties, such as sedimentary layers. Modelling of the so-called ‘tsunami earthquakes’ suggests that an event for which 10% of the moment release takes place in sediments generates a tsunami 10 times larger than its seismic moment would suggest. We also investigate the properties of non-double couple sources and find that their relative excitation of tsunamis and Rayleigh waves is in general comparable to that of regular seismic sources. In particular, landslides involving weak sediments could result in very large tsunamis. Finally, we emphasize that the final amplitude at a receiving shore can be strongly affected by focusing and defocusing effects, due to variations in bathymetry along the path of the tsunami.
Materials and growth issues for high-performance nonpolar and semipolar light-emitting devices

Growth of InGaN/GaN light-emitting devices on nonpolar or semipolar planes offers a viable approach to reducing or eliminating the issues associated with polarization-related electric fields present in c-plane III-nitride heterostructures. Although progress in device performance has been rapid since the introduction of high-quality free-standing nonpolar and semipolar GaN substrates, a full appreciation of the materials challenges unique to nonpolar and semipolar III-nitride semiconductors has been slower to emerge. Only recently have researchers begun to understand issues such as the origins of the pyramidal hillocks typically observed on nominally on-axis m-plane GaN films, the effects of m-plane substrate misorientation on surface morphology and device performance, the mechanics of anisotropic cracking in tensile strained m-plane AlGaN films, the formation of basal-plane stacking faults in long-wavelength m-plane InGaN quantum wells, and the mechanisms for stress relaxation in semipolar AlGaN and InGaN films. In this paper, we review the materials and growth issues unique to high-performance nonpolar and semipolar light-emitting devices grown on high-quality free-standing GaN substrates and provide an outlook for the opportunities and challenges that lie ahead. (Some figures in this article are in colour only in the electronic version)
Foraging impact on zooplankton by age-0 walleye pollock (Theragra chalcogramma) around a front in the southeast Bering Sea

The waters around the Pribilof Islands in the southeast Bering Sea are a center of abundance for age-0 walleye pollock (Theragra chalcogramma). Each spring and summer a tidal front is formed around the islands separating a well-mixed inshore habitat from a stratified offshore habitat. The objective of this study was to assess the foraging impact on zooplankton by age-0 pollock in the vicinity of this frontal structure. A bioenergetic model was used to estimate age-0 pollock food consumption from field estimates of water temperature, age-0 pollock density, diet and growth. Sampling of field variables took place over three hydrographic habitats along an inshore–offshore transect located north of the islands. The bioenergetics analysis was applied for a 2-week period during the late summer of four consecutive years, 1994–1997. Model results of age-0 pollock food consumption indicated variable levels of food depletion, changing with prey type, year and habitat. The foraging impact of age-0 pollock on copepods and euphausiids (most common prey) ranged from about 3% to 77% of the biomass available at the start of the simulation. Copepod depletion was typically greater than euphausiid depletion. Consequently, juvenile pollock <60 mm in standard length were more likely to experience food limitation due to the greater proportion of copepods in their diet. We present evidence of severe foraging impact during 1996, when one of the primary prey items of juvenile pollock (i.e. large copepods) was scarcely represented both in their diet and in the water column. In all years, most instances of prey depletion were found at the inshore and front habitats; age-0 pollock densities were too low relative to their prey to severely impact the offshore zooplankton populations. We discuss these results with respect to modeling assumptions and in the context of previously acquired knowledge of fish behavior around frontal regions.
High-Dose Continuous Nebulized Levalbuterol for Pediatric Status Asthmaticus: A Randomized Trial

Objective To assess the use of high-dose continuous levalbuterol (LEV), the single active (R)-enantiomer of racemic albuterol (RAC), in the treatment of status asthmaticus. Study design Children age 6 to 18 years with severe asthma exacerbation were enrolled in this randomized, double-blind trial if they failed initial emergency department (ED) therapy with RAC and systemic steroids. Subjects received equipotent doses of RAC (20 mg/hour) or LEV (10 mg/hour) within a standardized inpatient protocol. Blood samples for measurements of albuterol enantiomer, potassium, and glucose levels were obtained from the first 40 subjects. The median time until discontinuation of continuous therapy was compared using the rank-sum test, and other outcomes were compared using general linear mixed models. Results A total of 81 subjects (40 in the RAC group and 41 in the LEV group) were enrolled; the 2 groups were similar at baseline. Both groups tolerated continuous therapy with similar changes in heart rate and serum potassium and glucose levels but higher serum (S)-albuterol concentrations in the subjects treated with RAC. The median time for continuous therapy was similar in the RAC and LEV groups (18.3 hours vs 16.0 hours), as were the other clinical measures. Conclusions Substituting high-dose continuous LEV for RAC did not reduce the time on continuous therapy and had similar adverse effects in children who had failed initial treatment with RAC.
Portacaval Anastomosis and Hepatic Hemosiderin Deposition: A Prospective, Controlled Investigation

Postshunt hemosiderosis is characterized by the rapid generalized deposition of hemosiderin after portacaval anastomosis (PCA) in patients who had been free of hemosiderin pre-PCA. It has been suggested that this phenomenon occurs in 10 to 20% of shunted patients. A prospective study of hepatic hemosiderin deposition was performed in conjunction with controlled investigations of prophylactic PCA. This study included 103 patients (57 control and 46 shunt patients), who represented all the patients in whom liver biopsies were performed at the time of inclusion and in whom subsequent specimens of liver tissue were available after an interval of at least 6 months. Iron stains were read blindly and were graded semiquantitatively on several occasions by the same observer. Reproducibility of grading was excellent. Pre-PCA iron was found in 27% of the control and 36% of the shunt patients and was similar in amount in both groups. Post-PCA, an average of 4 years later, iron was found in 27% of the control and 50% of the shunt patients. The mean amount of iron which had not changed in the control group (0.27+ to 0.25+) increased markedly in the shunt group (0.28+ to 0.90+). The age, and type, duration and severity of cirrhosis, the duration of follow-up, amount of endogenous oral iron, and number of transfusions administered were similar in both groups. In 10 patients excessive hepatic hemosiderin accumulation was noted. Nine were in the shunt group (20%) and 1 was in the control group (2%). Pancreas, heart, adrenal, and kidney also showed hemosiderin deposition in these patients. The deposition was observed after both end-to-side and side-to-side PCA. Four of the 9 patients with postshunt hemosiderosis developed congestive heart failure; 3, skin pigmentation; and 2, diabetes. Serum iron levels, which had previously been normal, were increased in 5 of the 9.
The built environment and alcohol consumption in urban neighborhoods

Objectives: To examine the relations between characteristics of the neighborhood built environment and recent alcohol use. Methods: We recruited participants through a random digit dial telephone survey of New York City (NYC) residents. Alcohol consumption was assessed using a structured interview. All respondents were assigned to neighborhood of residence. Data on the internal and external built environment in 59 NYC neighborhoods were collected from archival sources. Multilevel models were used to assess the adjusted relations between features of the built environment and alcohol use. Results: Of the 1355 respondents, 40% reported any alcohol consumption in the past 30 days, and 3% reported more than five drinks in one sitting (heavy drinking) in the past 30 days. Few characteristics of the built environment were associated with any alcohol use in the past 30 days. However, several features of the internal and external built environment were associated with recent heavy drinking. After adjustment, persons living in neighborhoods characterized by poorer features of the built environment were up to 150% more likely to report heavy drinking in the last 30 days compared to persons living in neighborhoods characterized by a better built environment. Conclusions: Quality of the neighborhood built environment may be associated with heavy alcohol consumption in urban populations, independent of individual characteristics. The role of the residential environment as a determinant of alcohol abuse warrants further examination. © 2007 Elsevier Ireland Ltd. All rights reserved.
Tumor-specific imaging through progression elevated gene-3 promoter-driven gene expression

Molecular-genetic imaging is advancing from a valuable preclinical tool to a guide for patient management. The strategy involves pairing an imaging reporter gene with a complementary imaging agent in a system that can be used to measure gene expression or protein interaction or track gene-tagged cells in vivo. Tissue-specific promoters can be used to delineate gene expression in certain tissues, particularly when coupled with an appropriate amplification mechanism. Here we show that the progression elevated gene-3 (PEG-3) promoter, derived from a rodent gene mediating tumor progression and metastatic phenotypes, can be used to drive imaging reporters selectively to enable detection of micrometastatic disease in mouse models of human melanoma and breast cancer using bioluminescence and radionuclide-based molecular imaging techniques. Because of its strong promoter activity, tumor specificity and capacity for clinical translation, PEG-3 promoter-driven gene expression may represent a practical, new system for facilitating cancer imaging and therapy.
The Copper Content of Butter Made by a Continuous Method

Summary A method for measuring the Cu content of butter has been presented that has been found satisfactory. The Cu in milk products has been found to be associated with the non-fat portion rather than the fat phase. In two cases out of three, butters made by the continuous process contained less Cu than the original cream when the Cu content was expressed on the fat basis. Butter made by the continuous process in four commercial creameries contained less Cu than butter made by the batch system in the University dairy plant. Eleven samples of butter made by the continuous process were found to contain from 0.12 to 0.27ppm. of Cu on a total weight basis with an average of 0.19ppm. The centrifugal treatment given cream in the process of making butter by the continuous method results in concentration of the Cu in the non-fat portion. Butter oils made by the centrifugal process in the continuous method of making butter contain only minute traces of Cu.
Neoliberalism and the City

It’s great to be here and, particularly, to celebrate the beginning of a journal with such an auspicious title. I have long been interested in questions of social justice; one of my first books was Social Justice and the City. For me, it was a revelatory book to write and I hope that it will one day be a revelatory book to read; but sometimes, as in this instance, you learn far more by writing than by reading. My book was about the city and I would like to start with one of my favourite quotations about cities, which is by Robert Park, a Sociologist writing in Chicago in the 1920s. Park put it this way about cities, he said:
Introduction to the ME curriculum through product engineering case studies

Product engineering, through reverse engineering and team projects, is an effective way to introduce freshmen of diverse backgrounds to Mechanical Engineering (ME) and provide them with a world introductory exposure to product design, manufacturing and systems operation. This paper discusses several components of the ldquoEngineering Experiencesrdquo course developed at Stevens Institute of Technology (SIT), which aims to provide entering students with hands-on experiences and exposures to the world of operating mechanical systems. Students from a variety of engineering majors work in teams to dissect products, analyze their function by applying appropriate operating principles, design alternatives by building simplified physical models of a system, develop technical drawings, exchange drawings with different groups to manufacture their product, test and operate the product. Examples of products studied in the class include gear pumps, sewing machines, engines, electric drills, electrical screw drivers, toys, etc. The range of products on the selection list provides a great deal of insight and helps students enhance their understanding of what the discipline has to offer. Student feedback confirms that the course helps them develop a clear overview of the different fields within ME, gives them a general idea of what mechanical engineering work is about, and how the upcoming curricular elements as they relate to especially engineering science contribute to the development of expertise especially important to the product engineering.
Metapopulation dynamics: Indirect effects and multiple distinct outcomes in ecological risk assessment

A toxicant-dosed metapopulation model was used to explore the range of possible dynamics of populations in contaminated field sites. A single species metapopulation model was developed that is discrete, deterministic, and incorporates doseresponse curves and biotic growth rates to describe the effects of contamination on a metapopulation. The distribution of the chemical contamination is assumed limited to one patch and contagious within that patch. Both persistent and degradable toxicants were modeled. Five principal conclusions resulted from our simulation studies. (1) Mortality in one subpopulation has ecologically significant effects on nondosed subpopulations. This hypothesis we term “action at a distance” because no direct contact with a toxicant has occurred except in the dosed patch. (2) Because uncontaminated sites connected to the contaminated site by migration of the biota are affected, these uncontaminated sites cannot be reference sites. (3) The arrangement of the patches is critical to the dynamics of the system and the overall impact of a toxicant. (4) Due to the contagious distribution of the toxicant and the stochastic function describing exposure effect, multiple discrete outcomes often are possible from the same initial conditions. These outcomes can range from extinction to the reaching of the carrying capacity for a patch. (5) If sufficient cleanup is not possible, it may be necessary to isolate the contaminated patch, allowing the formerly connected patches to regain more typical population dynamics.
The Major Yolk Protein of Sea Urchins Is Endocytosed by a Dynamin-Dependent Mechanism

Sea urchin oocytes grow to 10 times their original size during oogenesis by both synthesizing and importing a specific repertoire of proteins to drive fertilization and early embryogenesis. During the vitellogenic growth period, the major yolk protein (MYP), a transferrin-like protein, is synthesized in the gut, transported into the ovary, and actively endocytosed by the oocytes. Here, we begin to dissect this mechanism by first testing the hypothesis that MYP endocytosis is dynamin-dependent. We have identified a sea urchin dynamin cDNA that is highly similar in amino acid sequence, structure, and size to mammalian dynamin I: it contains an N-terminal GTPase domain, a pleckstrinhomology domain, and a C-terminal proline-rich domain. Sea urchin dynamin is enriched at the cortex of oocytes and colocalizes to MYP endocytic vesicles at the oocyte periphery. To test for a functional relationship between MYP endocytosis and dynamin, we used a dominant-negative human dynamin I mutant protein containing an alteration within the GTPase domain (hDynK44A) to specifically compete for dynamin function. Using a fluorescent MYP construct to follow its endocytosis solely, as well as a general endocytosis marker, we demonstrate that the disruption of dynamin function significantly reduces MYP uptake but does not affect fluid-phase endocytosis. Using this specific biochemical approach, we are able to separate distinct pathways of endocytosis during oogenesis and learn that dynamin-mediated endocytosis is responsible for MYP endocytosis but not fluid-phase uptake. gamete biology, gametogenesis, oocyte development
EARNINGS OVER THE LIFE CYCLE: WHAT DO HUMAN CAPITAL MODELS EXPLAIN?

It is argued that labor market success is perhaps the most important indicator of individual welfare. As such, this paper surveys recent developments in human capital theory to explain how earnings vary across the population. The paper begins with standard life cycle accumulation models which explain why earnings rise at a diminishing rate over one's life cycle. These models are then modified to incorporate (1) school quality to explain race differences in earnings, (2) intermittent labor force participation to explain gender wage differentials, (3) heterogeneous human capital to explain occupational choice, (4) matching to explain geographic and job mobility, and (5) search to explain workers' and firms' incomplete information. Finally, additional extensions are considered to incorporate effort enhancing contracts as a special case. Copyright 1995 by Scottish Economic Society.