cssi/SciSciGPT-SciSciNet huggingface dataset:
Solving Very Sparse Rational Systems of Equations

Efficient methods for solving linear-programming problems in exact precision rely on the solution of sparse systems of linear equations over the rational numbers. We consider a test set of instances arising from exact-precision linear programming and use this test set to compare the performance of several techniques designed for symbolic sparse linear-system solving. We compare a direct exact solver based on LU factorization, Wiedemann’s method for black-box linear algebra, Dixon’s p-adic-lifting algorithm, and the use of iterative numerical methods and rational reconstruction as developed by Wan.
Image Reconstruction In The Presence Of Noise

Correlographic image reconstruction, using pupil-plane intensity patterns generated by a coherently-illuminated object, has been simulated O and has successfully reproduced the density mask used to drive the simulation. We describe a set of experiments in which a physical object was illuminated, and detector-plane intensity readouts were used as the input to correlographic reconstruction software. The effects of dark current bias, finite analog-to-digital conversion error, and additive noise are evaluated. The correlogram construction process includes inward extrapolation for smoothing of the D.C. spike. The phase retrieval process includes annealing and median filtering. As compared with the simulated results, the experimental results show greater difficulty in convergence and a lower fidelity in the reconstructed image.
β-alanine Supplementation Fails to Increase Peak Aerobic Power or Ventilatory Threshold in Aerobically Trained Males

The purpose of the present study was to determine the effect of 30 days of β-alanine supplementation on peak aerobic power and ventilatory threshold (VT) in aerobically fit males. Fourteen males (2...
Evaluation of phase separation in glasses with the use of atomic force microscopy

Abstract Glass forming melts frequently exhibit liquid–liquid immiscibility resulting in phase separation. The chemical and spatial variation of phase separated morphologies in glasses can range from a few angstroms to microns, often requiring very high magnification for detection. Historically, phase separated glasses have been characterized by transmission electron microscopy (TEM). This technique is very time consuming and costly, requiring specialized equipment and training. Atomic force microscopy (AFM) provides an inexpensive alternative to TEM and has proven to be a powerful tool in the characterization of phase separation in glasses. AFM provides rapid and accurate evaluation of the type, degree and scale of phase separation in glasses down to the nanometer level. Using a combination of topographical and phase imaging AFM we were able to quantitatively determine the microstructures of phase separated glasses with a resolution down to 50 nm. Additionally we were able to quantitatively confirm the time dependence of the chemical segregation and growth processes for phase separation in glass by spinodal decomposition. This paper will present sample preparation techniques and results for evaluation of phase separation in alkali borosilicate and sodium silicate glass systems.
The Role Of Chemical Reaction In Waste-Form Performance

The dissolution rate of waste solids in a geologic repository is a complex function of waste form geometry, chemical reaction rate, exterior flow field, and chemical environment. We present here an analysis to determine the steady-state mass transfer rate, over the entire range of flow conditions relevant to geologic disposal of nuclear waste. The equations for steady-state mass transfer with a chemical-reaction-rate boundary condition are solved by three different mathematical techniques which supplement each other. This theory is illustrated with laboratory leach data for borosilicate-glass and a spherical spent-fuel waste form under typical repository conditions. For borosilicate glass waste in the temperature range of 57°C to 250°C, dissolution rate in a repository is determined for a wide range of chemical reaction rates and for Peclet numbers from zero to well over 100, far beyond any Peclet values expected in a repository. Spent-fuel dissolution in a repository is also investigated, based on the limited leach data now available.
Repeated long separations from pups produce depression-like behavior in rat mothers

Long maternal (LMS) versus brief maternal (BMS) daily separations of rat pups from their mothers have contrasting effects on their adult stress responses and maternal behavior by, respectively, decreasing and increasing licking received from their mothers. We hypothesized that LMS decreases pup-licking in mothers by inducing learned helplessness, creating a depression-like state. We subjected postpartum rats to LMS (3 h), BMS (15 min) or no separation (NMS) on postpartum days 2-14. After weaning, mothers were given a forced swim test (FST). LMS mothers exhibited more immobility and fewer escape attempts than BMS or NMS mothers. These results suggest that LMS induces a depression-like state, which may account for the reductions in maternal behavior seen in LMS mothers. Immobility in the FST is recognized as an animal model of depression. Therefore, LMS may be a model of maternal depression.
Peptide mimetics as enzyme inhibitors: Use of free energy perturbation calculations to evaluate isosteric replacement for amide bonds in a potent HIV protease inhibitor

We present the application of free energy perturbation theory/molecular dynamics to predict the consequence of replacing each of the seven peptide bonds in the potent HIV protease inhibitor JG365: ACE (acetyl)-Ser-Leu-Asn-HEA (hydroxyethylamine analog of Phe-Pro)-Ile-Val-NME (N-methyl) by ethylene or fluoroethylene isosteres. Replacing two of these bonds may well lead to significantly tighter binding; replacing two others is predicted to significantly diminish the binding affinity. Also, for three of the peptide bonds fluoroethylene replacements could lead to increased binding of free energies of the inhibitors. Our results should be considered as predictive since there are, as yet, no experimental results on such peptide replacements as enzyme inhibitors.
Psychiatric Diagnoses of 901 Inpatients Seen by Consultation-Liaison Psychiatrists at an Academic Medical Center in a Managed Care Environment

The authors reviewed the diagnoses from all inpatient psychiatric consultations conducted by faculty psychiatrists during calendar year 2001 (N = 901) at an academic medical center. In about 25% of the consultations, multiple psychiatric diagnoses were made. The most frequent diagnosis groups were mood (40.7%), cognitive (32.0%), and substance use disorders (18.6%). Among 671 consultations in which only one diagnosis was made, the rates of these diagnosis groups were 35.4%, 20.1%, and 10.2%, respectively. The findings were compared with the findings of 19 previous studies published over the past 27 years. Mood, cognitive, and substance use disorders remain major foci of consultation-liaison practice in the managed care era, although the rate of cognitive disorder diagnoses has increased. No evidence was found of a change over time in referral rates.
A bio-sensing strategy for the detection of prions in foods

Abstract An affinity based bio-sensing technique was developed using an anti-transmissible spongiform encephalopathy monoclonal antibody to detect prion in 0.1 mol/l sodium phosphate buffer. Fluoresein iso-thio-cyanate (FITC) labeled with a prion epitope (QYQRES) was used as a decoy for prions. Lowest detectable prion concentration was 8 nmol/l in phosphate buffer. The bio-sensing scheme was used to probe the presence of prions in gelatin and baby-formula. The gelatin interfered with the binding and the displacement reaction of antibody, decoy and prion. Addition of sodium dodecyl sulfate (SDS) at 0.3 mg/ml to gelatin samples facilitated prion detection in gelatin. The lowest detectable concentration of prion in gelatin was 0.5 nmol/l at 0.4 mg/ml gelatin. The baby formula samples produced light scattering and the intrinsic peak of baby formula interfered with the dye peak. Serial dilutions of baby formula were done to reduce the interference. Addition of Triton-X-100 at 0.454 mg/ml to the baby formula samples facilitated the prion detection. The lowest detectable concentration of prion was 2 nmol/l for baby formula.
Magnetoquantum oscillations of the phonon-drag thermoelectric power in heterojunctions.

A theory is presented for the low-temperature phonon-drag thermopower {ital S}{sub {ital xx}} in a semiconductor heterojunction in a strong magnetic field. Gigantic quantum oscillations (much larger than electron-diffusion contributions) are obtained. The temperature and field dependences of {ital S}{sub {ital xx}} agree well with recent data. Localized states yield flat valleys for the {vert bar}{ital S}{sub {ital xx}}{vert bar} minima in agreement with the data.
Radiative Transport in Disordered Photonic Crystals

The theory of the radiative transfer is developed for disordered photonic crystals. The radiative transfer equation is derived for the specific intensity of the photonic modes. Basic transport properties are studied near the equilibrium regime.
Infrared absorption spectra of nitrogen oxides in liquid xenon. Isomerization of N2O3 a)

Infrared absorption spectra of nitrogen oxides present when NO and NO2 are dissolved in liquid xenon between 160 and 220 K have been measured. Spectral absorptions of NO, NO2, (NO)2, N2O4, and N2O3 are identified, and integrated absorption cross sections are given for several spectral features. The spectra suggest that symmetric N2O3 and asymmetric N2O3 are in equilibrium in solution and that the energy difference between these two isomers is 1.8±0.2 kcal/mol.
Cold hardiness and winter survival in the bird flea, Ceratophyllus idius

Abstract Adults of the purple martin flea Ceratophyllus idius Jordan and Rothschild, were sampled from outdoor and −6°C freezer-held populations from early September to mid-April of two consecutive years. Levels of polyols (glycerol, sorbitol) and carbohydrates (glycogen, glucose, trehalose) were monitored and correlated with temperatures in both regimens. Natural autumn cooling and controlled laboratory chilling (3°C every fourth day) produced large increases in glycerol levels with concomitant declines in glycogen. These processes appeared to commence at about +10°C and continued at subzero temperatures until glycerol content averaged 443 ± 14.9 μmol/g wet wt and glycogen fell to an average of 17 ± 1.1 μmol/g. Sorbitol levels remained low at all times (1–3 μmol/g), although glucose and trehalose content showed transitory, 2-fold increases during cold acclimation. Supercooling points declined and stabilized at −29 to −30°C in both regimens. Glycerol levels in freezer-held fleas remained nearly constant throughout the experiment, while outdoor specimens showed monthly fluctuations and a large decline by mid-April. The springtime decrease was not linked to a comparable rise in glycogen content. In outdoor samples, 32.4% of the fleas were still alive in mid-April, approx 10 days prior to the expected return of migrant birds.
Lower the boom on the lowly pronoun

Careless use of certain pronouns in technical writing today causes communication to be a fuzzy and inept as many other writing flaws. The pronouns most commonly misused are the demonstratives, this and that with their plurals these and those; such relatives as which, who, whom, and that, and the anticipatory expletive it. Eliminating the irritating and confusing aspects of these often misused pronouns is simple. More effective and efficient technical communication will result.
Recording characteristics of monopolar emg electrodes

Motor unit action potentials (MUAPs) and the electromyographic (EMG) interference pattern (IP) were recorded from the biceps muscle of 5 normal subjects using both a concentric needle (CN) and a disposable monopolar needle (MN) electrode. The MUAPs recorded by the MN electrode had higher amplitude and area and were more frequently complex than those recorded with the CN electrode. The MUAP duration and area: amplitude ratio were similar for both electrodes. Although the MN electrode had a larger recording surface, its dimensions (maximum diameter and length of the cone shaped tip) were similar to those of the CN electrode (minor and major axes of the elliptical recording tip). Based on these observations, we infer that the MN electrode may be more selective than the CN electrode, ie, the AP amplitude recorded by the MN electrode decreases faster than the AP amplitude recorded by a CN electrode when the distance of the muscle fiber from the recording electrode increases. Photomicrographs of the MN electrode after use demonstrated no evidence that the insulating material had peeled off. There was also no evidence that MUAP measurement values changed during the recordings as would be expected if the recording surface changed due to peeling of the insulating material.
Moderators of Cardiovascular Reactivity to Speech: Discourse Production and Group Variations in Blood Pressure and Pulse Rate

To explain why speech produces cardiovascular reactivity, an experiment utilized speech tasks varying in self-disclosure and cognitive preparation and measured the blood pressure and pulse rate of African-American and Caucasian, men and women subjects. One hundred and fifty-six college students with a median age of 21 volunteered to participate. The extemporaneous speech task produced lower systolic blood pressure than the prepared speech task. Self-disclosive speech resulted in lower diastolic blood pressure than non-disclosive speech. Females showed higher pulse rate and men exhibited greater diastolic blood pressure while speaking. Results supported previous research suggesting that women are myocardiacal hyperreactors, while men are vascular hypperreactors and suggest that production processes moderate cardiovascular reactivity to speech.
Human cytomegalovirus. Cytochemical observations of intracellular lesion development correlated with viral synthesis and release

Abstract The evolution of the intracytoplasmic and intranuclear lesions produced by a human cytomegalovirus in human embryo cells is described and the lesions characterized cytochemically. Twenty-four hours after infection basophilic, lipid-containing, PAS-positive bodies surrounded by a halo containing RNA appear in a juxtanuclear position in the cytoplasm. Forty-eight hours after infection amphophilic patches that contain DNA and viral antigen appear in the nucleus. The cytoplasmic lesion also contains viral antigen at this time. Seventy-two hours after infection, the cytoplasmic lesion contains DNA and the nucleus is significantly enlarged. At about this time, infectious virus is first found intracellularly, and shortly thereafter release into the medium begins.
Some coherent-states aspects of the electron nuclear dynamics theory: past and present

Past and present coherent-states (CS) efforts with the electron nuclear dynamics (END) theory at its simplest level (SL-END) are reviewed. END is a time-dependent, variational, non-adiabatic, direct-dynamics method that describes simultaneously the nuclei and electrons of a molecular system. Within that characterization, SL-END adopts a classical-mechanics description for the nuclei and a quantum single-determinantal representation for the electrons. From its very inception, SL-END has been associated with the CS theory. CS sets are continuous and over-complete sets that satisfy the resolution of identity with a positive measure. Different CS sets can play an astonishing number of roles within SL-END that have several practical consequences. Originally, SL-END utilized the canonical and Thouless CS sets to correctly represent the nuclear and electronic parts of the SL-END wavefunction, respectively, thus defining a proper phase space for the SL-END dynamical equations. Later, canonical and rotational CS s...
Schumann resonance effects of electrical conductivity perturbations in an exponential atmospheric/ionospheric profile

Abstract Eigenmode solutions are computed for the n = 1 … 3 Schumann resonances in a perturbed, unmagnetized vertical atmospheric conductivity profile σ = 10 −16 exp ( z /3.1) mho m −1 for z ⩽ 100 km and σ = 10 −2 mho m −1 for z > 100 km. For the unperturbed exponential profile the radial electric field E r is nearly constant z ≲ 40 km, and decreases rapidly above 50 km. The tangential field E ϑ > E r for z ≳ 65 km. The Joule dissipation profile in this case has an absolute maximum at about 50 km and a smaller relative maximum at 90 km with a deep relative minimum at 65 km. The maximum dissipation thus occurs in the middle atmosphere, making the Schumann resonances particularly susceptible to conductivity perturbations in this region. The perturbations of this study comprise Gaussian-shaped enhancements or depressions of FWHM ≈ 10 km impressed on the unperturbed profile. Eigenfrequencies and Q -values are computed for the full range of perturbation amplitudes 10 −3 −10 3 and altitudes 30–90 km. The perturbations induce overall eigenfrequency variations of ± 1.0, ±1.5, and ±2.5 Hz in the n = 1, 2, and 3 modes, respectively, and Q -values spanning the range 3.5–11.0. The results of this calculation extend those of previous works investigating the Schumann resonance response to atmospheric conductivity perturbations, and may be useful for interpreting experimental observations in terms of external ionization source intensities of GCR, Lyman-α, or solar cosmic or X-rays, or variations in middle atmospheric chemical constituents.
Perceptual Threshold of Discrete Movement in Motion Pictures

The perception of discrete movement it related to visual angle, the angle subtended at the spectator by the displacement of the screen image between two successive frames. This paper determines the perceptual threshold of discrete movement in terms of visual angle for a limited set of conditions.
Retention of volatile components during freeze drying of substances containing emulsified oils

Summary Measurements have been made of the retention of a series of volatile acetates during freeze drying of sucrose solutions containing emulsified vegetable oils. The acetates partition to different extents between the oil and aqueous phases. The observed retentions can be interpreted in terms of a simple model whereby acetate located in oil droplets initially present in regions ultimately occupied by ice crystals are lost completely, whereas acetate in oil droplets present within residual concentrate are fully retained, and acetate in the aqueous phase is lost according to observations for initially homogeneous systems. As a general rule, only a small fraction of the oil droplets are present within the residual concentrate, and extraction of volatiles into an emulsified oil phase reduces volatiles retention during freeze drying. The results and the model afford a rational interpretation of the results reported by Kayaert, Tobback & Maes (1974) for retention of individual aldehydes and mixtures of aldehydes during freeze drying of a model food system.
Hypoxia/reoxygenation increases the permeability of endothelial cell monolayers: role of oxygen radicals.

We assessed the effect of hypoxia/reoxygenation on 14C-albumin flux across endothelial monolayers. Cultured bovine pulmonary artery endothelial cells were grown to confluence on nitrocellulose filters (pore size 12 microns). The endothelialized filters were mounted in Ussing-type chambers which were filled with cell culture medium (M 199). Equimolar amounts (33 nM) of 14C-labeled and unlabeled albumin were added to the hot and cold chambers, respectively. The monolayers were then exposed to successive periods (90 min) of normoxia (pO2 145 mmHg), hypoxia (pO2 20 mmHg), and reoxygenation (pO2 145 mmHg). A gas bubbling system was used to control media pO2 and to ensure adequate mixing. Four aliquots of culture media were taken during each period in order to calculate the 14C-albumin permeability across the endothelialized filter. In some experiments, either the xanthine oxidase inhibitor, oxypurinol (10 microM), or superoxide dismutase (600 U/mL), was added to the media immediately prior to the experiments. As compared to the normoxic control period, albumin permeability was 1.5 times higher during hypoxia (p less than 0.01) and 2.3 times higher during reoxygenation (p less than 0.01). The reoxygenation-induced increase in albumin permeability was prevented by either oxypurinol or superoxide dismutase. These data indicate that xanthine oxidase-derived oxygenmore » radicals contribute to the hypoxia/reoxygenation-induced endothelial cell dysfunction. The altered endothelial barrier function induced by hypoxia/reoxygenation is consistent with the microvascular dysfunction observed following reperfusion of ischemic tissues.« less
Aerodynamically-driven condensate layer thickness distributions on isothermal cylindrical surfaces

A simple yet rather general mathematical model is presented for predicting the distribution of condensate layer thickness when aerodynamic shear is the dominant mechanism of liquid flow along the surface. The Newtonian condensate film is treated using well-known thin-layer (lubrication theory) approximations, and condensate supply is taken to be the result of either convective diffusion or inertial impaction. Illustrative calculations for a circular cylinder in a crossflow at Re = 100,000 reveal the consequences of alternate condensate arrival mechanisms and the existence of thicker reverse-flow films behind the position of gas boundary-layer separation. The present formulation is readily generalized to include transient liquid layer flows on noncircular objects of variable surface temperature, as encountered in turbine-blade materials testing or operation.
Multifocal electroretinography in HIV-positive patients without infectious retinitis

Purpose To evaluate early changes in the central retinal response in human immunodeficiency virus (HIV)-positive patients without infectious retinitis using multifocal electroretinography (mfERG). Design Case control study. Methods We evaluated three cohorts: HIV-negative controls and two groups of HIV-positive patients separated according to their nadir CD4 counts (≥ 100 cells/mm 3 and 3 for a minimum of six months). mfERG first-order kernels (FOKs) and second-order kernels (SOKs) were analyzed separately by areas of rings, quadrants, and individual hexagons for each cohort. Results Of 103 hexagon locations of FOK results, there were no significant differences in amplitudes of P1 and N1 across the groups (.05 P P P Conclusions The results demonstrate widespread delay in latency in HIV-positive patients, especially in those with prolonged low (below 100 cells/mm 3 ) CD4 nadir counts. These findings suggest early diffuse dysfunction of the inner retina results from severe HIV disease even in the HAART era.
Spectroscopic and Electrochemical Probes of Electronic Coupling in Some Cyanide-Bridged Transition Metal Donor/Acceptor Complexes

The effects of donor−acceptor (D/A) electronic coupling, HDA, on the spectroscopic and electrochemical properties of several series of CN--bridged transition metal complexes have been examined. The complexes employed were formed by ruthenation of M(L)(CN)2n+ parent complexes (for n = 0, M = Ru(II) or Fe(II), and L = bpy or phen; for n = 1, M = Cr(III), Rh(III), or Co(III), and L = bpy, phen, or a tetraazamacrocyclic ligand). The observed half-wave potentials of the resulting CN--bridged D/A complexes spanned a 300−350 mV range in contrast to the range of about 80 mV expected on the basis of the oscillator strength, hDA, of the D/A charge-transfer MM‘CT absorption band and the geometrical distance between donor and acceptor, rDA. Different series of complexes exhibit different correlations between E1/2 and hDA. Several factors have been found to contribute to these differences: (a) symmetry effects; (b) solvational differences that arise when nonbridging ligands are changed; (c) solvational effects arisin...
REPRESENTING RESPONDENTS UNDER NEW CIVIL COMMITMENT STATUTES: An Analysis of Counsel's Role In and Out of the Courtroom

Using quantifiable attorney behavior measures, instead of outcome measures, both before and during court hearings, this study attempts to evaluate legal representation under reform civil commitment procedures. Counsel representing involuntary commitment respondents full time were well prepared. Court appointed counsel, though better prepared than reported in studies done prior to reform, did not fully investigate their cases. Lack of adequate preparation was associated with a passive role and a non adversary position in court.
Correlated energy disposal and scattering dynamics of the Cl CD4(ν3 = 2) reaction

Molecular chlorine, methane and helium are co-expanded into the extraction region of a Wiley-McLaren time-of-flight spectrometer. After preparing the first overtone of the antisymmetric stretch (ν3 = 2) with direct IR excitation, the reaction is initiated by photolysing Cl2 with 355 nm light to produce mono-energetic Cl atoms with a translational energy of 0.18 eV. The CD3 and DCl products are state-selectively detected via resonance enhanced multiphoton ionization (REMPI) and analysed with the core-extraction technique. Unusual structure in the 3pz CD3 REMPI spectrum suggests the presence of a previously unobserved transition, which we assign to the stretch-bend combination ( [image omitted]) band. The product correlated energy disposal and the scattering distributions are compared with the same quantities for the Cl + CH4(ν3 = 2) reaction and found to be similar, although subtle differences are observed. The results for the Cl + CD4(ν3 = 2) reaction support a localized chemistry model in which the Cl at...
Neutrophil trails guide influenza-specific CD8+ T cells in the airways

During viral infections, chemokines guide activated effector T cells to infection sites. However, the cells responsible for producing these chemokines and how such chemokines recruit T cells are unknown. Here, we show that the early recruitment of neutrophils into influenza-infected trachea is essential for CD8(+) T cell-mediated immune protection in mice. We observed that migrating neutrophils leave behind long-lasting trails that are enriched in the chemokine CXCL12. Experiments with granulocyte-specific CXCL12 conditionally depleted mice and a CXCR4 antagonist revealed that CXCL12 derived from neutrophil trails is critical for virus-specific CD8(+) T cell recruitment and effector functions. Collectively, these results suggest that neutrophils deposit long-lasting, chemokine-containing trails, which may provide both chemotactic and haptotactic cues for efficient CD8(+) T cell migration and localization in influenza-infected tissues.
Medicine at the Millennium

What will the future bring? Will biomedical advances move rapidly and affordably into clinical practice, stimulated by the demands of the educated consumer? Or will changes in the way health care is financed and physician inability to stay abreast of clinical changes widen the gap between high-quality and mediocre medical care? Is there a limit to what we can afford to provide, regardless of availability?
A methodology to evaluate the availability of reconfigurable conveyor systems

Networked sensor-actuator systemspsila technologies significantly impact the design of future automation systems. Since the automation domain is critical, there is a need to ensure high availability of the system. A model-based approach to evaluate system availability offers systematic, quantitative guidance on the effectiveness of different topologies and failure recovery mechanisms. We present a methodology to evaluate the availability of a simple class of automation systems, namely reconfigurable conveyor systems in which each conveyor unit is regulated by a local micro-controller. Microcontrollers in different units interact via wireless communications. The availability of the conveyor system depends on the correct functioning of each unit in the system. We assume that only the sensors, actuators and mechanical components of units can fail, i.e., the microcontrollers and radio transceivers do not fail. Because the Stochastic Reward Nets (SRN) paradigm provides the capability to integrate notions of performance and service value, we use this paradigm as the basis of our methodology. At the lowest level, the operational and failure states of each unit are considered to model unit-level availability. Next, the states of units are combined to provide path metrics and states. Finally, at the third level path metrics and states are composed to obtain system-level metrics. We illustrate how the methodology provides key design guidance and operational guidance using an example of an Inspection Station (IS) conveyor system.
The 3C syndrome: Evolution of the phenotype and growth hormone deficiency

The 3C syndrome (cranio-cerebello-cardiac dysplasia or the Ritscher-Schinzel syndrome) is a recently delineated condition involving abnormalities of the cranium (large head with prominent forehead), cerebellum (Dandy-Walker cyst and vermis hypoplasia), and cardiac (primarily septal) defects. At least 20 individuals with this condition have been reported in the past 11 years. We report on a girl with the 3C syndrome who at 13 years of age is the oldest patient reported to date. She has been followed since birth, allowing us to show the evolution of her phenotype over time. In addition, she has documented growth hormone deficiency. We suggest that growth hormone deficiency should be considered as a possible cause of the short stature often seen in this condition.
Staying alive: bacterial inhibition of apoptosis during infection

The ability of bacterial pathogens to inhibit apoptosis in eukaryotic cells during infection is an emerging theme in the study of bacterial pathogenesis. Prevention of apoptosis provides a survival advantage because it enables the bacteria to replicate inside host cells. Bacterial pathogens have evolved several ways to prevent apoptosis by protecting the mitochondria and preventing cytochrome c release, by activating cell survival pathways, or by preventing caspase activation. This review summarizes the most recent work on bacterial anti-apoptotic strategies and suggests new research that is necessary to advance the field.
Electrical resistivity of submicron-diameter carbon-filament compacts

The electrical resistivity of submicron-diameter carbon-filament compacts was decreased by increasing the filament diameter from 0.05 to 0.16 μm, and also by graphitization of the filaments. The use of nickel-coated carbon filaments gave even lower resistivity. The compacts exhibited lower resistivity than the corresponding polymer-matrix composites, such that the difference between compact and composite diminished with increasing filament volume fraction.
Molecular Approach to Adenosine Receptors: Receptor-Mediated Mechanisms of Tissue Protection

Adenosine accumulation during ischemia and inflammation protects tissues from injury. In ischemic tissues adenosine accumulates due to inhibition of adenosine kinase, and in inflamed tissues adenos...
Faster repair of DNA double-strand breaks in radioresistant human tumor cells.

Abstract To investigate the molecular basis of radiation resistance in human tumor cells, the induction and repair of radiation-induced DNA single- and double-strand breaks was determined by DNA elution analysis in two normal human cell lines and 12 early-passage human tumor cell lines of varying radiosensitivities. The radiosensitivities (D 0 ) of the cell lines ranged from 1 to 2.9 Gy. Inherent cellular radiosensitivity was found to directly correlate with the rate at which the DNA double-strand breaks were repaired. Radioresistant cell lines repaired approximately 90% of their radiation-induced DNA double-strand breaks within 1 hr of irradiation while more radiosensitive cell lines required 2–4 hr to repair the same fraction of damage. Radioresistant cell lines also had lower initial DNA double-strand break frequencies. DNA single-strand break induction and repair was not found to be an important factor in the radiation response of human tumor and normal cell lines. Therefore, the rate at which DNA double strand breaks are repaired is a critical factor underlying radioresistance in human tumor cell lines.
DETERMINATION OF COMPLEX SURFACE STRUCTURES WITH LEED

The evolution of the complexity of structural determination attainable with LEED is reviewed. Considerable progress in methodologies and computers has enabled structures as complex as Cu(100) + (4 × 4)- 10Li to be solved in terms of 18 fit parameters. The Si(111)-(7 × 7) structure could now be refined in terms of 100-or-so fit parameters, if a large-enough experimental dataset were available. Big challenges remain: finding a direct or quick way to identify the one qualitatively correct structure; and, to a lesser degree, providing the required size of the experimental dataset.
Nickel and Vanadium Concentrations and Its Relation with Sediment Acute Toxicity

Sediments from Panuco River historically have contained elevated levels of numerous contaminants that may pose risks to ecological receptors and humans. Sediments were sampled and characterized to determine the acute sediment toxicity and its relationship with contaminants. Results demonstrated that toxicity was significantly correlated with fitness index (r = 0.82, p < 0.001), TOC (r = 0.55, p < 0.5), Ni (r = 0.95, p < 0.001), and V (r = 0.93, p < 0.001), but not with PAHs (r = 0.20, p < 0.5) during rainy and dry seasons. Although a great heterogeneity exists, the river outlet presents the biggest problems, due to dredging allow the metal desorption from solid to water phase, increasing the metal bioavailability.
Sensor Node Localization Using Uncontrolled Events

Many event-driven localization methods have been proposed as low cost, energy efficient solutions for wireless senor networks. In order to eliminate the requirement of accurately controlled events in existing approaches, we present a practical design using totally uncontrolled events for stationary sensor node positioning. The novel idea of this design is to estimate both the event generation parameters and the location of each sensor node by processing node sequences easily obtained from uncontrolled event distribution. To demonstrate the generality of our design, both straight-line scan and circular wave propagation events are addressed in this paper, and we evaluated our approach through theoretical analysis, extensive simulation and a physical test bed implementation with 41 MICAz motes. The evaluation results illustrate that with only randomly generated events, our solution can effectively localize sensor nodes with excellent flexibility while adding no extra cost at the resource constrained sensor node side. In addition, localization using uncontrolled events provides a nice potential option of achieving node positioning through natural ambient events.
Percutaneously inserted central catheters in the newborns: A center's experience in Turkey

Objective. To evaluate the success rate of insertion of percutaneously inserted central catheters (PICCs) and their duration; and the short- and long-term complications in the neonatal period.Study design. We did a prospective collection and analysis of the data of all infants who underwent PICC placement from January 2005 and through January 2007. During this period there were 139 PICCs inserted in a total of 124 infants. The data of all infants were compiled, including birth weight, gestational age, diagnosis, type of catheter, site of catheter placement, reason for catheter removal, duration of use of the catheter, and the rate of complications.Results. The success rate of PICC insertion was 88.5% with the upper extremity being the most frequently used site. The mean duration of PICC treatment was 11.9 ± 6.3 days. PICCs were removed electively for 72 times (54.1%) and due to catheter-related complications for 61 times (45.9%). The main complication rate was the mechanical occlusion (12.7%). There were ...
Assessing the Health Perspectives of Unique Populations of Adolescents: A Focus Group Study

Few articles report on youth's perceptions about health-related issues and needs and even fewer have given voice to youth with disabilities, chronic health conditions, or youth in therapeutic foster care. The purpose of this study was to explore perceptions of health issues from the perspectives of youth placed in therapeutic foster care, youth with chronic medical conditions, and youth with disabilities. Twelve focus groups with 67 youth aged 13–20 were conducted in rural, suburban, and urban communities in the Commonwealth of Virginia. Data analysis revealed both within unique group themes and themes that cut across unique groups. Youth in therapeutic foster care with chronic health conditions or with disabilities perceive themselves as being different from their peers. Participants in each group expressed concerns about the unique issues that they confront daily and how these challenges differentiate them from youth who do not share their life experiences. They expressed the desire for other youth to u...
Transition, stress and computer-mediated social support

This review of literature from multiple disciplines argues that the Internet is useful both in communicating support, and in the rapid reestablishment of socially supportive peer networks, when an individual’s support needs change following a transition. We extend prior typologies of transition by identifying common features and outcomes of transition. We subsequently describe how transition involves a loss of social support networks and social capital, leading to increased stress and decreased wellbeing. Finally, we examine the features of computer mediated social support, and how those align with support needs following a transition. This paper provides a theoretical underpinning and a common language for the study of transition and its associated stress. The paper also suggests that computer-mediated social support may in some instances be superior to available face-to-face support options for managing the transitional factors affecting stress.
Black on white meeting slides best

While I agree with Randall S. Jacobson (Eos, June 9, 1992) that better slides are needed at meetings and that colored lines or words on a black background are difficult to read, I disagree that white on black is the best alternative.
IFN-λ Exerts Opposing Effects on T Cell Responses Depending on the Chronicity of the Virus Infection

IFN-λ induces an antiviral state in many cell types and may contribute to the overall inflammatory environment after infection. Either of these effects may influence adaptive immune responses, but the role of type 3 IFNs in the development of primary and memory T cell responses to infection has not been evaluated. In this study, we examined T cell responses to acute or persistent lymphocytic choriomeningitis virus infection in IFN-λR1-deficient mice. Following acute infection, we find that IFN-λR1-deficient mice produced normal levels of IFN, robust NK cell responses, but greater than normal CD4+ and CD8+ T cell responses compared with wild type BALB/c mice. There were more T cells that were IL-7R(hi) and, correspondingly, the IFN-λR-deficient mice showed a 2- to 3-fold increase in memory T cell number. The inhibitory effect of IFN-λR expression was independent of direct cytokine signaling into T cells. In contrast with acute infection, the IFN-λR-deficient mice generated markedly diminished T cell responses and had greater weight loss compared with wild type mice when confronted with a highly disseminating variant of lymphocytic choriomeningitis virus. These data indicate that IFN-λR limits T cell responses and memory after transient infection but augments T cell responses during persisting infection. Thus, the immune-regulatory functions for IFN-λR are complex and vary with the overall inflammatory environment.
INSECT AND MITE ASSOCIATES OF SCOLYTUS MULTISTRIATUS (COLEOPTERA: SCOLYTIDAE) IN CALIFORNIA

Thirty-four species of insects associated with Scolytus multistriatus (Marsham) were reared or collected from several species of elm collected throughout California. Few of these species occurred in large numbers and many of their ecological roles in this subcortical habitat are unknown. Predators were uncommon; only 6 species of parasitic Hymenoptera were reared, 3 of which were not previously known from California. One, Dendrosoter protuberans (Nees), had previously been released for biological control of S. multistriatus only as far west as Colorado. The most abundant insect associate reared from northern California, Cheiropachus quadrum (F.), exhibited a maximum percentage parasitism of 2%. Seven species of mites, including 2 new species, were also collected in association with S. multistriatus.
Drug use and five-year incidence of age-related cataracts: The Beaver Dam Eye Study

Abstract Objective To evaluate incident cataract after a 5-year interval with respect to medication use. Design Population-based incidence study. Main outcome Incident cataract judged from standard photographs. Setting Study subjects were adults 43 to 86 years of age in 1988 to 1990 and again in 1993 to 1995. All participants were examined and interviewed, and photographs were taken. All procedures and grading were done by protocols at both examinations. All medications in current use, prescribed as well as over-the-counter, were brought to the examination site, and the names were recorded at that time. Results There were 678 drug preparations (active ingredients) being used at the baseline examination. Significantly lower incidences of nuclear cataracts 5 years later occurred in those who took thiazide diuretics (odds ratio [OR] = 0.79, 95% confidence interval [CI] 0.63, 1.00) and aspirin (OR = 0.76, 95% CI 0.61, 0.95) at the baseline examination. There were significantly more incident cortical cataracts in those taking oral steroids (OR = 2.59, 95% CI 1.45, 4.62), amitriptyline (OR = 2.03, 95% CI 1.09, 3.79), oral hypoglycemic agents (OR 2.06, 95% CI 1.23, 3.44), and insulin (OR = 3.38, 95% CI 1.61, 7.08). There were significantly more incident posterior subcapsular cataracts in those taking potassium-sparing diuretics (OR = 2.13, 95% CI 1.42, 3.18) and oral hypoglycemic agents (OR = 2.89, 95% CI 1.57, 5.33). Considering past use with never and current use did not alter the patterns of associations. We were not able to separate the effects of antihypertensive or diuretic agents from that of hypertension. However, hypoglycemic agents were no longer associated with any cataract type after stratifying by diabetes status. Conclusions Although many different medications were being used at the baseline examination in the Beaver Dam Eye Study cohort, few were associated with incident cataract. However, with the high frequency of use of medications and the possibility that effects of current exposure may occur in the future, it is reasonable to follow this and other older cohorts for the development of cataract.
Stochastic learning feedback hybrid automata for dynamic power management in embedded systems

In this paper we show that stochastic learning automata based feedback control switching strategy can be used for dynamic power management (DPM) employed at the system level. DPM strategies are usually incorporated at the operating systems of embedded devices to exploit multiple power states available in today's ACPI compliant devices. The idea is to switch between power states depending on the device usage, and since device usage times are not deterministic, probabilistic techniques are often used to create stochastic strategies, or strategies that make decisions based on probabilities of device usage spans. Previous work (Irani et al., 2001) has shown how to approximate the probability distribution of device idle times and dynamically update them, and then use such knowledge in controlling power states. Here, we use stochastic learning automata (SLA) which interacts with the environment to update such probabilities, and then apply techniques similar to (Irani et al., 2001) to optimize power usage with minimal effect on response time for the devices.
Redox initiated cationic polymerization: Silane-N-aryl heteroaromatic onium salt redox couples

In this article, a new route for the synthesis of N-aryl heteroaromatic onium salts by the direct copper catalyzed arylation of pyridine, substituted pyridines, isoquinoline, and acridine with diaryliodonium salts is described. It was demonstrated that these N-aryl heteroaromatic onium salts undergo facile platinum or rhodium-catalyzed reduction by silanes bearing Si—H groups. The reduction of N-aryl heteroaromatic onium salts generates Bronsted acids. When this redox reaction was carried out in situ in the presence of an appropriate monomer, cationic polymerization was observed. Using this approach, the cationic polymerizations of epoxides, oxetanes, 1,3,5-trioxane, styrene, and vinyl ethers were carried out. The use of optical pyrometry to monitor the redox initiated cationic polymerizations of some representative multifunctional monomers is described.
Investigating lipid interactions and the process of raft formation in cellular membranes using ToF-SIMS

Abstract There is an increased interest in how lipids interact with each other, especially in the lateral separation of lipids into coexisting liquid phases as this is believed to be an attribute of raft formation in cell membranes. ToF-SIMS has shown itself to be an excellent tool for investigating cellular and model membrane systems and will be perhaps the most powerful one for investigating raft formation. Results from our laboratory show the capability of ToF-SIMS at identifying unequivocally the content of coexisting liquid lipid phases. Using supported lipid monolayers we find that the inclusion of dipalmitoylphosphatidylethanolamine (DPPE) to a homogeneous dipalmitoyl-phosphatidylcholine (DPPC)/cholesterol phase results in the formation of cholesterol-rich domains [A.G. Sostarecz, C.M. McQuaw, A.G. Ewing, N. Winograd, J. Am. Chem. Soc. 126 (2004) 13882]. Also, for DPPE/cholesterol systems a single homogeneous DPPE/cholesterol phase is formed at ∼50 mol% cholesterol, whereas DPPC/cholesterol systems form a single phase at 30 mol% cholesterol [C.M. McQuaw, A. Sostarecz, L. Zheng, A.G. Ewing, N. Winograd, Langmuir 21 (2005) 807]. Currently we are exploring the incorporation of sphingomyelin into phospholipid–cholesterol mixtures in an effort to gain a better understanding of its role in raft formation.