cssi/SciSciGPT-SciSciNet huggingface dataset:
Acute Increase in Deaths Among Patients With Adult Congenital Heart Disease During COVID-19: Single-Center Experience

Abstract Fear of acquiring severe acute respiratory syndrome coronavirus-2 infection is a major contributor to underutilization of the health care system during the current pandemic. In this report...
The SARS-CoV-2 spike protein alters barrier function in 2D static and 3D microfluidic in vitro models of the human blood-brain barrier

As researchers across the globe have focused their attention on understanding SARS-CoV-2, the picture that is emerging is that of a virus that has serious effects on the vasculature in multiple organ systems including the cerebral vasculature. Observed effects on the central nervous system includes neurological symptoms (headache, nausea, dizziness), fatal microclot formation and in rare cases encephalitis. However, our understanding of how the virus causes these mild to severe neurological symptoms and how the cerebral vasculature is impacted remains unclear. Thus, the results presented in this report explored whether deleterious outcomes from the SARS-COV-2 viral spike protein on primary human brain microvascular endothelial cells (hBMVECs) could be observed. First, using postmortem brain tissue, we show that the angiotensin converting enzyme 2 or ACE2 (a known binding target for the SARS-CoV-2 spike protein), is expressed throughout various caliber vessels in the frontal cortex. Additionally, ACE2 was also detectable in primary human brain microvascular endothelial (hBMVEC) maintained under cell culture conditions. Analysis for cell viability revealed that neither the S1, S2 or a truncated form of the S1 containing only the RBD had minimal effects on hBMVEC viability within a 48hr exposure window. However, when the viral spike proteins were introduced into model systems that recapitulate the essential features of the Blood-Brain Barrier (BBB), breach to the barrier was evident in various degrees depending on the spike protein subunit tested. Key to our findings is the demonstration that S1 promotes loss of barrier integrity in an advanced 3D microfluid model of the human BBB, a platform that most closely resembles the human physiological conditions at this CNS interface. Subsequent analysis also showed the ability for SARS-CoV-2 spike proteins to trigger a pro-inflammatory response on brain endothelial cells that may contribute to an altered state of BBB function. Together, these results are the first to show the direct impact that the SARS-CoV-2 spike protein could have on brain endothelial cells; thereby offering a plausible explanation for the neurological consequences seen in COVID-19 patients.
Investigating the use of conducting oligomers and redox molecules in CdS–MoFeP biohybrids

In this work we report the effect of incorporating conducting oligophenylenes and a cobaltocene-based redox mediator on photodriven electron transfer between thioglycolic acid (TGA) capped CdS nanorods (NR) and the native nitrogenase MoFe protein (MoFeP) by following the reduction of H+ to H2. First, we demonstrate that the addition of benzidine-a conductive diphenylene- to TGA-CdS and MoFeP increased catalytic activity by up to 3-fold as compared to CdS–MoFeP alone. In addition, in comparing the use of oligophenylenes composed of one (p-phenylenediamine), two (benzidine) or three (4,4′′-diamino-p-terphenyl)phenylene groups, the largest gain in H2 was observed with the addition of benzidine and the lowest with phenylenediamine. As a comparison to the conductive oligophenylenes, a cobaltocene-based redox mediator was also tested with the TGA-CdS NRs and MoFeP. However, adding either cobaltocene diacid or diamine caused negligible gains in H2 production and at higher concentrations, caused a significant decrease. Agarose gel electrophoresis revealed little to no detectable interaction between benzidine and TGA-CdS but strong binding between cobaltocene and TGA-CdS. These results suggest that the tight binding of the cobaltocene mediator to CdS may hinder electron transfer between CdS and MoFe and cause the mediator to undergo continuous reduction/oxidation events at the surface of CdS.
Prazoles Targeting Tsg101 Inhibit Release of Epstein-Barr Virus following Reactivation from Latency.

Epstein-Barr virus (EBV) is a ubiquitous herpesvirus responsible for several diseases including cancers of lymphoid and epithelial cells. EBV-cancers typically exhibit viral latency; however, the production and release of EBV through its lytic phase is essential for cancer development. Antiviral agents that specifically target EBV production do not currently exist. Previously, we reported that the proton pump inhibitor Tenatoprazole, which blocks the interaction of ubiquitin with the ESCRT-1 factor Tsg101, inhibits production of several enveloped viruses, including EBV. Here, we show that three structurally distinct prazoles impair mature particle formation post-reactivation and identify the impact on stages of replication. The prazoles did not impair expression of lytic genes representative of the different kinetic classes but interfered with capsid maturation in the nucleus as well as virion transport from the nucleus. Replacement of endogenous Tsg101 with a mutant Tsg101 refractory to prazole-mediated inhibition rescued EBV release. These findings directly implicate Tsg101 in EBV nuclear egress, and identify prazoles as potential therapeutic candidates for conditions that rely on EBV replication such as chronic active EBV infection and post-transplant lymphoproliferative disorders.IMPORTANCEProduction of virions is necessary for the ubiquitous Epstein-Barr virus (EBV) to persist in humans but in so doing, can set the stage for development of EBV-cancers in at-risk individuals. In our attempts to identify inhibitors of the EBV lytic phase, we previously found that a prazole proton pump inhibitor, known to block the interaction of ubiquitin with the ESCRT-1 factor Tsg101, blocks production of EBV. We now find that three structurally distinct prazoles impair maturation of EBV capsids and virion transport from the nucleus, and by interfering with Tsg101, prevent EBV release from lytically-active cells. Our findings not only implicate Tsg101 in EBV production but also identify widely-used prazoles as candidates to prevent development of post-transplant EBV-lymphomas.
The Life of Percy Bysshe Shelley and Shelley’s Poetics of Reticence: Shelley’s Shame: The Life of Percy Bysshe Shelley, by John Worthen, Chichester, Wiley-Blackwell, 2019, xxi + 480 pp., 14 illustrations

Reading John Worthen’s The Life of Percy Bysshe Shelley together with Merrilees Roberts’s Shelley’s Poetics of Reticence: Shelley’s Shame is a study in contrasts. Worthen writes an accessible, enga...
First-principles calculation of lattice distortions in four single phase high entropy alloys with experimental validation

Abstract Exceptional properties of high entropy alloys (HEAs) are attributed to the disordered random solid solution of multiple alloying elements. Despite numerous studies, the fundamental understanding at the electronic and atomic levels is still missing. We report a comparative study of four fcc HEAs of NiFeCoCr and NiFeCoCrX (X = Mn, Cu, or Pd) based on ab initio calculations using large supercells with 500 atoms in equal composition. After fully optimizing their structures using the VASP package, their electronic structure, interatomic bonding, partial charge distribution, and mechanical properties are calculated and compared, revealing the intricate interdependence among them. A novel parameter based on the quantum mechanical metric for internal cohesion, the total bond order density (TBOD), is used to interpret the calculated properties. The highest TBOD is found in Cantor alloy NiFeCoCrMn but lower in NiFeCoCrPd. The atomic radii vary depending on their local chemical environment. The resulting lattice distortions is validated experimentally in NiFeCoCrMn and NiFeCoCrPd. Moreover, modeling of Cu and Pd clustering in the supercell shows they have lower total energy in agreement with the observation of Cu-enhanced nano-participates in NiFeCoCrCu and Pd-induced concentration wave in NiFeCoCrPd HEAs.
Use of Databases in Health Care

Now that the concepts and operational issues of databases in health care have been summarized, the application of databases in health care settings can be brought forward. We will first relate database uses to the categories of health care settings, and later in the chapter discuss specific types of applications in greater detail.
Frequency band selectable microwave photonic multiband bandpass filter based on Lyot filter

We present a microwave photonic multiband bandpass filter with four selectable operating states, which can either work as an all-block, single-pass or multi-pass bandpass filter with up to 46 dB sidelobe suppression.
Continuous finite element methods which preserve energy properties for nonlinear problems

Abstract Continuous finite elements are used to develop numerical methods which preserve energy properties for nonlinear ordinary and partial differential equations. Schemes are constructed that give high orders of accuracy. Time discretization algorithms for the Cahn-Hilliard, Klein-Gordon, Korteweg-de Vries, and Schrodinger equations are presented. Comparisons are made with existing schemes.
Rubidium-Strontium Isochron Study of the Grenville Front near Lake Timagami, Ontario

Rubidium-strontium isotopic analyses of whole-rock samples and of constituent minerals from a suite of rocks taken across the Grenville Front demonstrate that granitic rocks of the Superior province, with a primary age of approximately 2.4 billion years, and older metasedimentary rocks were reconstituted during Grenville metamorphism, at approximately 930 million years, and now form part of the Grenville province.
The co-extraction of nitric acid and uranyl nitrate by tributyl phosphate

The most satisfactory method for the determination of nitric acid in the presence of uranyl nitrate was the sodium oxalate complexing of uranium. The determinaiion of nitric acid in the organic phase was carried out by back extraction into a constant volume of water, addition of 2% sodium oxalate solution to the aqueous backwash, and titration with 0.5N sodium hydroxide using phenophihalein as indicator. The value obtained was corrected by comparison with a blank. (J.E.D.)
Parents’ facilitation of young children's writing

This study investigated the impact of a home composing curriculum on kindergarten children's concepts about print (a measure of reading readiness), writing fluency (the number of words children can write), and writing achievement. In addition, the study investigated gender differences on the above measures, types of writing done by children at home, and family members with whom children wrote. The treatment group was found to be significantly higher on the Concepts about Print test, writing fluency, and the first post‐test of writing achievement. There were no significant gender differences on any of the measures. Data from parent response sheets indicated that these children wrote notes, letters, and lists more than other types of writing. They wrote with their mother or alone more often than with other family members. The findings of this study suggest that a flexible home composing curriculum, combined with the sharing of writing at school can have an impact on reading readiness, the number of words ch...
Heritability of Live and Abdominal Fat Weights in Coturnix Quail

Abstract Twenty-seven single-pair matings of Coturnix quail produced 48 sons and 50 daughters. Parents and progeny were reared under similar conditions and killed at 58 days of age. Live and abdominal fat weights were obtained. Heritability estimates from parent-offspring regressions ranged from .05 to .72 (live weight), .49 to .80 (abdominal fat weight), and .45 to .88 (percent abdominal fat/live weight). The high heritabilities for live weight (except sire-daughter regression) and for abdominal fat in Coturnix quail indicate that a selection method could be used to reduce fat and increase live weight.
X-Ray and Optical Spectroscopy of IRAS 20181–2244: Not a Type 2 QSO, but a I Zw 1 Object

We analyze new optical spectra of IRAS 20181-2244 that confirm its classification as a I Zw 1 object (or narrow-line Seyfert 1 galaxy), one of 20 such objects detected in the ROSAT/IRAS all-sky survey. ASCA X-ray data on IRAS 20181-2244 support this classification since they are fitted by a simple power-law spectrum of Γ = 2.37 ± 0.09 that is typical of this class but steeper than that of ordinary Seyfert 1 or Seyfert 2 galaxies. Rapid X-ray variability is also observed in IRAS 20181-2244, ruling out a hidden/scattered QSO interpretation for this object. Its 0.5-10 keV luminosity is 5.5 × 1044 ergs s-1, and its variability signifies an efficiency of at least 4% for conversion of gravitational energy to X-rays. We discuss the important differences between the I Zw 1 class and the "type 2 QSO," or high-luminosity Seyfert 2 galaxy. While I Zw 1 objects of QSO-like luminosity are ubiquitous in infrared, optical, and soft X-ray selected samples, type 2 QSOs are rare, and there is a dearth of evidence for even a single one in X-rays. It is not clear how this imbalance relates to unified models of AGNs.
Electrical resistivity and band gap of marcasite (FeS2)

Abstract For a natural crystal of marcasite, an energy gap of 0.34 eV and an acceptor level at 0.052 eV are determined from temperature-dependent (53–370 K) electrical resistivity measurements. Magnetic susceptibilities and dielectric constants of marcasite and pyrite are compared in view of the large difference in their energy gaps.
Ammonia in the Atmosphere of Venus

Abstract Several aspects of the chemistry of NH3 in the Venus atmosphere are examined. Production of NH3 and precipitation of NH3 compounds are considered quantitatively. It is concluded that the high NH3 mixing ratios reported by the Soviet Venera 8 landing probe appear to be inconsistent with the observed abundances of other gases in the Venus atmosphere.
Reducing Disparities in Access to Primary Care and Patient Satisfaction with Care: The Role of Health Centers

This paper examined disparities in access to and satisfaction with primary care among patients of different racial/ethnic groups and insurance coverage, in health centers and the nation overall. Data came from the 2009 Health Center Patient Survey and 2009 Medical Expenditure Panel Survey. Study outcomes included usual source of care, type of usual source of care, satisfaction with provider office hours, and satisfaction with overall care. Health center patients were more racially and ethnically diverse than national patients, and health center patients were more likely than national patients to be uninsured or publicly insured. No significant health care disparities in access to care existed among patients from different racial/ethnic and insurance groups among health centers, unlike low-income patients nationwide or the U.S. population in general. Additional focus on the uninsured, in health centers and other health care settings nationwide, is needed to enhance satisfaction with care among these patients.
Remote sensing of chlorophyll concentration from space via principal component analysis of atmospheric effects

A methodology is proposed to retrieve marine reflectance and chlorophyll-a concentration from space by decomposing the satellite reflectance into principal components. The components sensitive to the ocean signal are combined to retrieve the principal components of marine reflectance, allowing reconstruction of marine reflectance and estimation of chlorophyll-a concentration. Multi-layered perceptrons are used to approximate the functions relating the useful principal components of satellite reflectance to the principal components of marine reflectance. The algorithm is developed and evaluated using non-noisy and noisy synthetic data sets created for a wide range of angular and geophysical conditions. In the absence of noise on satellite reflectance, the relative error on marine reflectance does not exceed 2%. Accurate retrieval of the first principal component of marine reflectance allows a global relative error of 5.4% on chlorophyll-a concentration. In the presence of 1% non-correlated and 5% spectrally correlated noise on satellite reflectance, the relative error is increased to 6% and 21%, respectively. Application to SeaWiFS imagery yields marine reflectance and chlorophyll-a concentration fields that resemble those obtained from the standard SeaWiFS processing, but are generally less contrasted. Accuracy can be improved by including bio-optical variability in the simulated marine reflectance ensembles.
A three-dimensional MHD solar wind model with pickup protons

[1] We have developed a three-dimensional (3-D) steady-state MHD model of the solar corona and solar wind that covers the region from the coronal base to 100 AU and that accounts for the effects of pickup protons in the distant heliosphere. The model expands the two-region model of Usmanov and Goldstein (2003) to include a region III that extends from 1–100 AU and incorporates a population of interstellar neutral hydrogen and its interaction with solar wind protons. Following the approach of Isenberg (1986) and Whang (1998), we consider the solar wind outside 1 AU as a combination of three comoving species, solar wind protons, electrons, and pickup protons, and solve the 3-D steady-state MHD equations with source terms due to photoionization and charge exchange. Separate energy equations are included for solar wind and pickup protons. We show that the pickup protons cause a deceleration of the solar wind and an increase in average plasma temperature with heliocentric distance beyond ∼10 AU. We compute the global structure of the solar wind from the coronal base to 100 AU and compare our results with Voyager 1 and 2 observations.
Pore metamorphosis during liquid phase sintering in microgravity

Liquid Phase Sintering (LPS) experiments have been conducted on several sounding rocket flights, Space Shuttle missions and aboard Mir Station, where more than 100 samples were processed for various times. Analysis of those samples revealed considerable pore formation and metamorphosis. Pore filling and coarsening was found in most samples while pore breakup was also found in low liquid volume samples. Pores showed bifurcated behaviors based on their liquid volume fractions. These behaviors resulted from particle rearrangement, particle growth and different diffusion patterns (surface diffusion and volume diffusion) that associated with interfacial energy differences, instabilities, and grain coarsening along the interface between phases. Low liquid volume fraction and the presence of the agglomeration, which results in high local solid volume fraction, enhances the volume diffusion during the process which causes the pore breakup. This paper attempts to show pore bifurcation behavior, which produces either smaller pore by a breakup mechanism or coarsened pore of large size. An initiation mechanism induced by grain growth, capillary force and other weak forces is proposed and the results from theoretical analysis and CFD numerical simulation are presented.
Structure Acquisition of the T1 Domain of Kv1.3 during Biogenesis

Abstract The T1 recognition domains of voltage-gated K + (Kv) channel subunits form tetramers and acquire tertiary structure while still attached to their individual ribosomes. Here we ask when and in which compartment secondary and tertiary structures are acquired. We answer this question using biogenic intermediates and recently developed folding and accessibility assays to evaluate the status of the nascent Kv peptide both inside and outside of the ribosome. A compact structure (likely helical) that corresponds to a region of helicity in the mature structure is already manifest in the nascent protein within the ribosomal tunnel. The T1 domain acquires tertiary structure only after emerging from the ribosomal exit tunnel and complete synthesis of the T1-S1 linker. These measurements of ion channel folding within the ribosomal tunnel and its exit port bear on basic principles of protein folding and pave the way for understanding the molecular basis of protein misfolding, a fundamental cause of channelopathies.
NMR studies of single crystals of H2. V. NMR anisotropy and order parameter distribution ofX (ortho)≤0.55

We report a study of the NMR line shapes in hcp single crystals of H2 with ortho concentrationsX≤0.55 in the regime where there is no longer a transition to a long-range orientationally ordered phase. From the anisotropy of the o-H2 impurity NMR spectrum at low ortho concentration, reached by ortho-para conversion, the crystal orientation is determined. The second momentM2 can be represented by a function of the formM2=Φ(X, T)f(cos θHc), where θHc is the angle between the applied magnetic field and the crystalc axis. For a single crystal, the anisotropy functionf(cos θHc) is found to be independent of temperature and of ortho concentration within experimental error, and is in very good agreement with predictions based on the first term of the high-temperature expansion ofM2 and on other, more general symmetry arguments. An order parameter σ is defined and the distribution functionP(σ) is calculated from the NMR line shapes under the simplifying assumption that the anisotropy of the order parameter, which gives rise to the observed anisotropy ofM2, can be neglected. We giveP(σ) as a function ofX at low temperature, where the line shape is only weakly dependent onT, and as a function ofT at constantX. It is found that the line shapes andP(σ) in both situations evolve continuously and give no hint of a phase transition. These results are discussed in relation to those of magnetic spin-glasses, and it is concluded that the orientational regime in solid H2, called a quadrupolar glass by previous investigators, cannot be distinguished by symmetry from the orientationally disordered phase that occurs at high temperature.
Making the Team: A Guide for Managers (2nd edition)

The article presents a review of the book "Making the Team: A Guide for Managers," 2nd edition, by Leigh L. Thompson.
Women in Law? A Review of Cynthia Fuchs Epstein's Women in Law

Cynthia Fuchs Epstein has written a sociological account of the number, locations, occupational categories, family histories, and attitudes of some women in the law, circa 1980.' The study is useful, informative, and thought provoking, and it raises a number of larger issues that deserve our interest and that I address here. A study about women in law concerns itself with gender differences, with deviance, with professionalism and occupational and organizational behavior, and finally with law. The questions put to us in this book all turn on issues of why women are or should be in law and what difference it makes if they are. To put it another way: we are informed that the numbers of women entering legal practice has increased dramatically in the past ten years. Women constitute close to 35% of the law student population (approximately 40,000 women students) and 12% of the legal profession (approximately 62,000 women lawyers) (pp. 4, 5, 21, 53). One is tempted to ask, so what? What difference does it make that there are now many more women law students, lawyers, law professors, and judges? What difference for the profession, what difference for women, what difference for the practice of law (in terms of how law is practiced and what law is practiced), and what difference for society? There are many ways to ask these questions and to answer them, and the choice of questions and the answers supplied may tell us more about the inquirer than about the subject. For Epstein the dependent variable is women. How have women been affected by their entry into the profession? How did they come to choose a career path that is difficult, full of head winds? How have women's lives changed as they have become lawyers? How have they coped with the demands of work life, family life, and individual fulfillment? One could ask these same questions of men who have chosen the demanding rigors of the legal profession. But Epstein finds women lawyers in-
Invasion of skin by schistosome cercariae: some neglected facts

Abstract In response to the Research Focus article by Rachel Curwen and Alan Wilson, some of the issues concerning invasion of skin by schistosome cercariae are addressed or clarified. The conclusions drawn by Curwen and Wilson concerning the kinetics of invasion and the exhaustion of schistosome acetabular glands are incorrect because they are based on rodent models and not on direct assessment of cercariae of human parasites that invade human skin.
Right Coronary Arterial Spasm Causing Prinzmetal's Variant Angina

Severe spasm of the right coronary artery was documented daring the second of three injections during coronary arteriography in a 42-year-old man with a five-year history of Prinzmetal's variant angina. Only mild atherosclerosis (
Drought tolerance and water use by plants along an alpine topographic gradient

In the alpine zones of western North American mountains, topographic-moisture gradients are the results of winter winds blowing snow from the upper windward slopes and ridgetops into snowdrifts on the lee slopes. Wet meadows at the foot of the lee slope are the result of summer snowmelt. Such gradients are repeated many times in a single mountain range. They are useful units for studies of the effects of drought and water use on patterning of alpine vegetation.The research was done through an entire growing season along a topographic gradient at 3,300 m in the Medicine Bow Mountains, Wyoming. Plant water potentials were measured on 29 species (pre-dawn to sunset) at weekly intervals. Simultaneously, leaf conductances were measured on 16 species of these; the remainder had leaves too small for the porometer. Leaf water potentials were generally lowest on the ridgetop and highest in the wet meadow. Highest mean leaf conductances were in the wet meadow plants; the lowest occurred on plants on the upper windward slope. None of the plants on the ridgetop had leaves large enough for the porometer. Plants of most species at all sites but the wet meadow showed sharply reduced leaf conductance or leaf death at plant water potentials below-1.5 MPa. Deep-rooted species such as Trifolium parryi showed maximal conductance at water potentials as low as-1.7 MPa and little reduction in conductance even at lower water potentials. Plant water potentials and leaf conductances showed close relationships with rooting depth, length of dry periods, and position on the gradient.
Quantitative assessment of patellar vascularity following bone‑patellar tendon‑bone autograft harvest for ACL reconstruction

Recent anatomic studies have suggested that the dominant arterial supply of the patella enters through the inferior pole. Based upon these findings, we hypothesized that bone-patellar tendon-bone graft harvest can significantly diminish patellar vascularity. Nine matched pair cadaveric knee specimens (mean age 47.4 years) were dissected and cannulated. A single knee was selected to undergo routine graft harvest, and the contralateral knee was left intact to serve as a control. Gadolinium was injected, and magnetic resonance imaging (MRI) signal enhancement was quantified to determine differences in uptake. Each matched pair was subsequently injected with a urethane polymer compound and dissected to correlate vessel disruption with MRI findings. We identified two predominating patterns of vessel entry. In one pattern, the vessel entered the inferomedial aspect (five o’clock/right, seven o’clock/left) of the patella and was disrupted by graft harvest in 2/9 (22.2 %) pairs. In the second pattern, the vessel entered further medial (four o’clock/right, eight o’clock/left) and was not disrupted (7/9, 78.8 %). The mean decrease in gadolinium uptake following disruption of the predominant vessel measured 56.2 % (range 42.6–69.5 %) compared to an average decrease of 18.3 % (range 7.1–29.1 %) when the dominant arterial supply to the inferior pole remained intact (p < 0.04). Medial entry of the predominant vessel precluded vessel disruption. Disruption of the dominant arterial supply can result in a significant decrease in patellar vascularity. Modification of graft harvest techniques and areas of surgical dissection should be explored to minimize vascular insult. Further correlation with clinical studies/outcomes is necessary to determine a potential association between vascular insult and anterior knee pain.
Noiseless propulsion for swimming robotic structures using polyelectrolyte ion-exchange membrane

In this paper a NafionTM polyelectrolyte ion-exchange membrane (IEM) was used as a propulsion fin for robotic swimming structures such as a boat or fish-like object swimming in water or aqueous medium. The Nafion membrane was chemically plated with platinum. The resulting membrane was cut in a strip to resemble a fish-like caudal fin for propulsion. A small function generator circuit was designed and built to produce approximately plus or minus 2.0 V amplitude square wave at varying frequency up to 50 Hz. The circuit board was mounted on a buoyant styrofoam shaped like a boat or a tadpole. The fin was attached to the rear of the boat. By setting the signal frequency to the desired value and thereby setting the frequency of bending oscillation of the membrane, a proportional forward propulsion speed could be obtained. The speed was then measured using a high speed camera. Several theoretical hydrodynamic models were then presented to characterize speed-frequency of the forward motion using available theories on biological fish motion. The results were compared to experimental data which showed close agreement. It turned out that the forward speed of the object was directly proportional to the product of frequency and amplitude of the fin oscillation as in biological fishes. This relation was further simplified by keeping the voltage constant and therefore amplitude of the oscillation. The proportionality constant could be measured for a known geometry of the fin-boat assembly and reactivity of the Nafion membrane used. The system as a whole presented an autonomous robotic swimming structure with frequency modulated propulsion to investigate application of polyelectrolyte hydrogel membranes and their effect on hydrodynamic behavior of an undulating swimming object. As in fishes the thrust force of the robot was generated by evolution of vortices on the sides of the undulating fin. For a constant forward speed, this thrust is equal to the drag force due to geometry and skin friction of the swimming robot. It was observed that regardless of the laminar or turbulent flow pattern around the robot the relation between speed and frequency holds. This research was a proof of concept for investigating fish propulsion known best for undulatory swimming motion, using polyelectrolyte ion-exchange-metal composite membrane.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Predation on juveniles of Crepidula fornicata by two crustaceans and two gastropods

Crepidula fornicata, the slippershell snail, while native to New England, has now become a successful invasive species along coastlines in many other parts of the world. This study considers the possible control of native populations by several common predators: the invasive shore crab Hemigrapsus sanguineus, one species of pagurid hermit crab (Pagurus longicarpus), and juveniles of the drilling gastropods Nucella lapillus and Urosalpinx cinerea. In the laboratory, juveniles of C. fornicata were especially vulnerable to the two crustacean predators tested, and to a lesser extent vulnerable as well to predation by the oyster drill U. cinerea; in choice tests, young oyster drills ate barnacles and mussels rather than slippershell snails, but ate C. fornicata when offered no other choice. Juveniles of two other Crepidula species (C. plana and C. convexa) were less susceptible to predation by hermit crabs, probably due to differences in juvenile shell morphology and growth trajectories. Remarkably, juvenile dogwhelks (N. lapillus) ate no Crepidula prey over several months in the laboratory, even in the absence of alternative food and although they readily consumed blue mussels. Additional work is needed to determine the role of crustacean and other predators in regulating the growth of native populations of C. fornicata in the field and to determine the extent to which the explosive growth of at least some invasive Crepidula populations reflects escape of juveniles from native predators.
A trypsin sensitive site for the action of hydrocortisone on calf thymus nuclei.

Abstract Hydrocortisone in physiological concentration caused a marked change in the circular dichroism spectrum of calf thymus nuclei. Selective hydrolysis of the histone components of the nuclei with trypsin inhibited with soy bean trypsin inhibitor rendered the treated nuclei unresponsive to the hormone. These results are interpreted as evidence for the involvement of histones in the interaction between hydrocortisone and calf thymus nuclei.
Effectiveness factors for heat transfer in fluidized beds

Rates of heat transfer associated with the evaporation of water from the surface of porous particles into air were measured for both packed and fluidized beds. Direct measurements of the temperature on the surface of these particles permitted the calculation of the heat transfer coefficient, hg, for both packed and fluidized bed systems. An effectiveness factor, χ, has been introduced to account for the non-plug flow characteristics of fluidized beds. This quantity has been used to define the rate of particle to gas heat transfer as follows where (δt)m represents the log-mean temperature difference across the bed and hg b is the heat transfer coefficient at the initiation of two phase fluidization defined as the “bubble point”. An analysis of the experimental measurements indicates that where g represents the ratio of the heat transfer factor of the fluidized bed to that corresponding at the bubble point of this bed. This effectiveness factor has also been related to the void fraction ratio as follows where ϵt, and ϵp, are the void fractions of the fluidized bed and its corresponding packed bed arrangement. This equation applies for ϵt/ϵp > 1.22. On a mesure les vitesses du transfert de la chaleur dans l'evaporation de l'eau dans l'air, a partir de la surface de particules poreuses, et ce dans le cas de lits garnis et fluidises. Des mesures directes de la temperature a la surface de ces particules a permis de calculer le coefficient de transmission de la chaleur pour les deux systemes de lit. On a introduit un facteur d'efficacite χ pour tenir compte des caracteristiques d'ecoulement non-obstrue des lits fluidises et l'a utilise pour definir la vitesse des particules par rapport au transfert de la chaleur du gaz, d'apres la relation suivante ou (δt)m represente la difference de temperature moyenne en logarithme dans le lit et hg b est le coefficient de transfert de la chaleur au point initial d'une fluidisation a deux phases qu'on appelle “point de bulle”. Une analyse des mesures experimentales indique que ou g est le rapport entre le facteur de transfert de la chaleur du lit fluidise et celui qui correspond au point de bulle de ce lit. On a egalement relie comme suit ce facteur d'efficacite au rapport des fractions de porosite ou ϵt, ϵp sont les fractions de porosite du lit fluidise et du lit garni. Cette equation s'applique dans le cas de ϵt/ϵp > 1.22.
Effect of reactant vibrational energy on spectator stripping product distributions

Abstract Simple expressions are given for product angular and translational energy distributions of the bimolecular reaction A + BC → AB + C assuming a spectator stripping mechanism which includes the effect of BC vibrational energy.
Capability of 11 antipneumococcal antibiotics to select for resistance by multistep and single-step methodologies.

Testing of 12 pneumococcal strains with differing resistotypes [including tet(M) positive] showed that tigecycline, amoxicillin-clavulanate, imipenem, and ceftriaxone did not select for resistant clones after 50 sequential subcultures. By comparison, azithromycin, clarithromycin, clindamycin, telithromycin, levofloxacin, moxifloxacin, and gemifloxacin did show resistant clones. Tigecycline also yielded a low frequency of resistance in single-step tests compared to all β-lactams, macrolides/ketolides, and quinolones tested.
USE OF BIODEGRADABLE MESH AS A TRANSPORT FOR A CULTURED UROEPITHELIAL GRAFT: AN IMPROVED METHOD USING COLLAGEN GEL

Abstract Objectives. To create an improved delivery vehicle for cultured uroepithelialcells using biodegradable mesh and collagen gel. Methods. Twenty uroepithelial grafts were prepared by seeding cultured urothelial cellsonto previously prepared collagen gel-polyglactin mesh. As a control, cells were seeded onto 20 plain polyglactin mesh (without gel) squares in the same fashion. Results. The presence of urothelial cells was confirmed in all cultures by immunohistochemistrytesting with anticytokeratin antibody. After 5 to 7 days, a confluent monolayer of cells covered 90% to 100% of the surface of all 20 collagen gel-mesh grafts. A confluent monolayer of cells did not form on any control graft (plain mesh). After 3 weeks, the cells had formed a sporadic, multiple cell layer confluence over 10% to 50% of the control graft surface; however, the mesh became friable and fell apart. Conclusions. By combining collagen gel with a biodegradable mesh scaffold, we createda surgically implantable cultured uroepithelial graft. The production of the collagen gel-mesh vehicle is simple and inexpensive. With this technique, the use of cultured urothelium for reconstructive urologic surgery can be investigated in greater detail.
Protein-tyrosine phosphatase inhibitors block tumor necrosis factor-dependent activation of the nuclear transcription factor NF-kappa B

Most of the inflammatory and proviral effects of tumor necrosis factor (TNF) are mediated through the activation of the nuclear transcription factor NF-kappa B. How TNF activates NF-kappa B, however, is not well understood. We examined the role of protein phosphatases in the TNF-dependent activation of NF-kappa B. Treatment of human myeloid ML-1a cells with TNF rapidly activated (within 30 min) NF-kappa B; this effect was abolished by treating cells with inhibitors of protein-tyrosine phosphatase (PTPase), including phenylarsine oxide (PAO), pervanadate, and diamide. The inhibition was dependent on the dose and occurred whether added before or at the same time as TNF. PAO also inhibited the activation even when added 15 min after the TNF treatment of cells. In contrast to inhibitors of PTPase, okadaic acid and calyculin A, which block serine-threonine phosphatase, had no effect. The effect of PTPase inhibitors was not due to the modulation of TNF receptors. Since both dithiothreitol and dimercaptopropanol reversed the inhibitory effect of PAO, critical sulfhydryl groups in the PTPase must be involved in NF-kappa B activation by TNF. PTPase inhibitors also blocked NF-kappa B activation induced by phorbol ester, ceramide, and interleukin-1 but not that activated by okadaic acid. The degradation of I kappa B protein, a critical step in NF-kappa B activation, was also abolished by the PTPase inhibitors as revealed by immunoblotting. Thus, overall, we demonstrate that PTPase is involved either directly or indirectly in the pathway leading to the activation of NF-kappa B.
Discovery and characterization of cooperative ligand binding in the adaptive region of interleukin-2

The cytokine hormone interleukin-2 (IL-2) contains a highly adaptive region that binds small, druglike molecules. The binding properties of this adaptive region have been explored using a "tethering" method that relies on the formation of a disulfide bond between the protein and small-molecule ligands. Using tethering, surface plasmon resonance (SPR), and X-ray crystallography, we have discovered that the IL-2 adaptive region contains at least two cooperative binding sites where the binding of a first ligand to one site promotes or antagonizes the binding of a second ligand to the second site. Cooperative energies of interaction of -2 kcal/mol are observed. The observation that the adaptive region contains two adjacent sites may lead to the development of tight-binding antagonists of a protein-protein interaction. Cooperative ligand binding in the adaptive region of IL-2 underscores the importance of protein dynamics in molecular recognition. The tethering approach provides a novel and general strategy for discovering such cooperative binding interactions in specific, flexible regions of protein structure.
Wavelength stealing: an opportunistic approach to channel sharing in multi-chip photonic interconnects

Silicon photonic technology offers seamless integration of multiple chips with high bandwidth density and lower energy-per-bit consumption compared to electrical interconnects. The topology of a photonic interconnect impacts both its performance and laser power requirements. The point-to-point (P2P) topology offers arbitration-free connectivity with low energy-per-bit consumption, but suffers from low node-to-node bandwidth. Topologies with channel-sharing improve inter-node bandwidth but incur higher laser power consumption in addition to the performance costs associated with arbitration and contention. In this paper, we analytically demonstrate the limits of channel-sharing under a fixed laser power budget and quantify its maximum benefits with realistic device loss characteristics. Based on this analysis, we propose a novel photonic interconnect architecture that uses opportunistic channel-sharing. The network does not incur any arbitration overheads and guarantees fairness. We evaluate this interconnect architecture using detailed simulation in the context of a 64-node photonically interconnected message passing multichip system. We show that this new approach achieves up to 28% better energy-delay-product (EDP) compared to the P2P network for HPC applications. Furthermore, we show that when applied to a cluster partitioned into multiple virtual machines (VM), this interconnect provides a guaranteed 1.27× higher node-to-node bandwidth regardless of the traffic patterns within each VM.
Self-Assembly and Odd−Even Effects of cis-Unsaturated Carboxylic Acids on Highly Oriented Pyrolytic Graphite

The self-assembly of several cis-unsaturated carboxylic acids of the structure cis-CH3(CH2)p-1CH=CH(CH2)m-1COOH on highly oriented pyrolytic graphite (HOPG) was studied. The impact of the interior cis-CH=CH group and the molecular chain length on their self-assembled structures was considered. Due to the cis conformation of the -HC=CH- group in the interior of these molecules, they display self-assembled structures significantly different from saturated acids with all-trans configurations. As an example of the class of molecules cis-CH3(CH2)p-1CH=CH(CH2)2n-1COOH (p not equal 2n) (p=8, n=7), cis-CH3(CH2)7CH=CH(CH2)13COOH self-assembles into two kinds of enantiomer domains with opposite 2-D chirality. Due to the steric restriction of the interior cis-HC=CH group, all chains with acid groups are packed at the same side of a lamella, a head-to-head arrangement which is different from the head-to-tail packing of saturated all-trans acids. However, cis-CH3(CH2)7CH=CH(CH2)8COOH, considered as one example of the group cis-CH3(CH2)p-1CH=CH(CH2)2n-2COOH (p not equal 2n-1) (p=8, n=5), does not form any stable self-assembled domain, consistent with the molecular arrangement model. This difference in self-assembly behavior between cis-CH3(CH2)p-1CH=CH(CH2)2n-1COOH (p not equal 2n) and cis-CH3(CH2)p-1CH=CHC2n-2COOH (p not equal 2n-1) shows an odd-even chain-length effect of cis-CH3(CH2)p-1CH=CH(CH2)m-1COOH (p not equal m, m=2n or 2n-1). For another category of molecules, cis-unsaturated acids with equal numbers of all-trans carbon atoms on both sides of the cis-CH=CH group, cis-CH3(CH2)m-1CH=CH(CH2)m-1COOH (m=2n or 2n-1), display another odd-even effect. cis-CH3(CH2)7CH=CH(CH2)7COOH, one example of cis-CH3(CH2)2n-1-CH=CH(CH2)2n-1COOH (n=4), is predicted to form both an enantiomer and a nonchiral racemic structure, which is in accordance with the experimental observation of its self-assembled monolayer. However, cis-CH3(CH2)2n-2CH=CH(CH2)2n-2COOH does not form a stable self-assembled domain due to the same steric repulsion as that seen in the cis-CH3(CH2)7CH=CH(CH2)8COOH structure. These odd-even effects demonstrate that molecular self-assembly can be significantly tailored by slightly changing the molecular chain length.
Adrenal cortical responses to low- and high-dose ACTH1–24 administration in major depressives vs. matched controls

Abstract Increased hypothalamo–pituitary–adrenocortical (HPA) axis activity occurs in 30–50% of patients with major depression. This includes normal-to-increased adrenal cortical hormone (cortisol) secretion in spite of reduced corticotropin (ACTH) stimulation. A possible explanation is increased adrenal responsiveness to ACTH. Supporting this possibility is the finding of increased adrenal volume, which reverts to normal with successful treatment. Eight female and six male patients with major depression, and eight female and six male individually matched controls, underwent two test sessions 5–7 days apart. On the first day, a low ACTH 1–24 dose (0.014 μg/kg i.v.), equivalent to 1 μg in a 70-kg individual, was given. On the second day, a supramaximal stimulating dose (250 μg i.v.) was given. Serial blood samples were analyzed for immunoreactive (IR-)ACTH, ACTH 1–39 , and cortisol. There were no significant sex or patient–control differences in IR-ACTH areas under the curve (AUCs) following low-dose ACTH 1–24 , and the correlation between patient and matched control AUCs was +0.71, indicating good correspondence in the amount of circulating ACTH 1–24 available for adrenal stimulation. There were no significant sex or patient–control differences in cortisol response and no significant interaction between dose and subject group, indicating that patients did not differ from controls in their cortisol responses to either low- or high-dose ACTH 1–24 . These findings do not indicate increased adrenal cortical responsiveness in patients with major depression. Neurochemical/neurohormonal and neural stimulatory factors other than ACTH might be responsible for the increased adrenal gland size and cortisol secretion, in spite of reduced pituitary ACTH secretion, that has been reported in this illness.
Expected number of passes in a binary search scheme

The binary search scheme is a method of finding a particular file from a set of ordered files stored in a computer. This scheme involves examining the middle file, and eliminating those files which do not contain the required file. This procedure is repeated until the required file is found. In this paper an exact expression for the expected number of passes required to find a file selected at random is derived. The expected number of passes is shown to be asymptotically equal to log2 k where k is the number of files. The asymptotic approximate values are compared to the exact values.