cssi/SciSciGPT-SciSciNet huggingface dataset:
B-type natriuretic peptide in children after cardiac transplantation.

Abstract Background The normal B-type natriuretic peptide (BNP) concentration and the significance of increased BNP concentration in children after orthotopic heart transplant (OHT) remain unknown. We sought to determine plasma BNP concentrations in relation to post-transplant time and to explore factors associated with increased BNP in pediatric OHT recipients. Methods We obtained plasma BNP concentrations in 44 pediatric patients at 1 to 171 months after OHT. All patients underwent endomyocardial biopsies and echocardiography. We analyzed the association between BNP and post-transplant time , as well as the association between BNP concentration and left ventricular end-diastolic dimension (LVEDD) after transplantation. Results The age of study patients ranged from 0.9 to 21.2 years (mean, 11.4 ± 6.2 years; median, 10.5 years). We evaluated BNP concentrations immediately after transplantation. The mean BNP concentration decreased exponentially to 100 pg/ml by 14 weeks after OHT. Although BNP concentration relative to time after OHT varied among individuals, all patients with multiple measurements showed predictable rates of decrease. This decrease in BNP concentration was not associated with changes in LVEDD. Conclusions Plasma BNP concentration was elevated in children after OHT and decreased exponentially in time to 100 pg/ml by 14 weeks after OHT. The decrease in BNP concentration was unrelated to left ventricular dimension.
Magnetic resonance imaging of massive bone allografts with histologic correlation

Objective. The objective of this study was to better understand the MRI appearance of massive bone allografts. Design. The MRI findings of three massive bone allografts imaged in vivo were correlated with the histologic findings following removal of the allografts. A fourth allograft, never implanted, was imaged and evaluated histologically. Patients. Allografts were placed for the treatment of primary or recurrent osteosarcoma. Results and conclusions. The in-vivo allografts have a heterogeneous appearance on MRI which we attribute to the revascularization process. Fibrovascular connective tissue grows into the graft in a patchy, focal fashion, down the medullary canal from the graft-host junction and adjacent to the periosteum. The marrow spaces are initially devoid of normal cellular elements and occupied by fat and gelatinous material. This normal postoperative appearance of massive bone allografts must not be interpreted as recurrent neoplasm or infection in the allograft. Recognition of these complications rests on features outside the marrow.
Automated screening of cervical cytology specimens

After more than four decades of research into automation of the process of screening Papanicolaou (Pap) smears, attempts to develop commercially viable automated screening machines have increased in recent years. These developments have been made possible in part because of the improving price-to-performance ratios in computers and other electronics. Although the Pap smear has been responsible for a very significant decrease in mortality of cervical cancer over the past 40 years, concern has arisen over false-negative cases, with their effects on patients, and the associated legal liability, particularly in the United States. In addition, shortages of cytotechnologists, which have been exacerbated by new regulations limiting the number of slides that may be examined per day, have caused concern about handling the workload, which will probably increase as more individuals gain access to preventive health care. Automated screening machines can potentially allow detection of abnormal cases that are missed with conventional screening, although they may substantially increase the cost of Pap smears. The use of automated screening machines represents a change in the way cervical cytology specimens are processed, and with some machines, a significant change in the operation of the cytology laboratory. Current methods for processing and evaluating Pap smears have not changed significantly for the past four decades. This review discusses some of the principles of operation and practical aspects of automated screening machines.
The Use of Additives for Reducing Hydrogen Yield in Mortar Containing Slag and Chloride Salts

Cementitious waste forms are being considered for immobilizing nuclear waste before disposal. In earlier work, it was found that irradiation of a mortar formulation consisting of slag, portland cement, fly ash, water, and up to 10 wt % KCl-LiCl salt resulted in the generation of hydrogen. Yields were relatively high and the rates of generation were constant for the irradiation period investigated. The addition of small amounts of oxygen-rich electron scavengers (NaNO3, NaIO4, KMnO4, or Ag2O) to the mortar was investigated as a means for reducing hydrogen yields. The addition of NaNO3 reduced the hydrogen yield; changed the radiolytic products from hydrogen to a mixture of hydrogen, nitrogen, and N2O; and reduced the pressurization rate after exposure to 400 Mrads. The addition of NaIO4 and KMnO4 reduced hydrogen yields slightly while the addition of Ag2O increased the yield. Moreover, the addition of FeS to a non-slag mortar changed the radiolysis mechanism but the addition of FeO did not. The results of these experiments provided an insight into the nature of the radiolytic reactions occurring in the mortar formulations and indicated that the radiolytic generation of gases might be controlled with the proper choice of additive.
Vibration Modes of Centrifugally Stiffened Beams

The method of Frobenius is used to solve for the exact frequencies and mode shapes for rotating beams in which both the flexural rigidity and the mass distribution vary linearly. Results are tabulated for a variety of situations including uniform and tapered beams, with root offset and tip mass, and for both hinged root and fixed root boundary conditions. The results obtained for the case of the uniform cantilever beam are compared with other solutions, and the results of a conventional finite-element code.
Two-dimensional probability density analysis of single channel currents from reconstituted acetylcholine receptors and sodium channels

Abstract Two-dimensional probability density analysis of single channel current recordings was applied to two purified channel proteins reconstituted in planar lipid bilayers: Torpedo acetylcholine receptors and voltage-sensitive sodium channels from rat brain. The information contained in the dynamic history of the gating process, i.e., the time sequence of opening and closing events was extracted from two-dimensional distributions of transitions between identifiable states. This approach allows one to identify kinetic models consistent with the observables. Gating of acetylcholine receptors expresses “memory” of the transition history: the receptor has two channel open (O) states; the residence time in each of them strongly depends on both the preceding open time and the intervening closed interval. Correspondingly, the residence time in the closed (C) states depends on both the preceding open time and the preceding closed time. This result confirms the scheme that considers, at least, two transition pathways between the open and closed states and extends the details of the model in that it defines that the short-lived open state is primarily entered from long-lived closed states while the long-lived open state is accessed mainly through short-lived closed states. Since ligand binding to the acetylcholine-binding sites is a reaction with channel closed states, we infer that the longest closed state (~19 ms) is unliganded, the intermediate closed state (~2 ms) is singly liganded and makes transitions to the short open state (~0.5 ms) and the shortest closed state (~0.4 ms) is doubly liganded and isomerizes to long open states (~5 ms). This is the simplest interpretation consistent with available data. In contrast, sodium channels modified with batrachotoxin to eliminate inactivation show no correlation in the sequence of channel opening and closing events, i.e., have no memory of the transition history. This result is, therefore, consistent with any kinetic scheme that considers a single transition pathway between open and closed states and confirms the CCO model previously inferred from one-dimensional distribution analysis. The strategy described should be of general validity in the analysis of single channel events from channel proteins in both natural and reconstituted membranes.
Characterization of chemically assisted ion beam etching and form birefringence structure fabrication in GaAs using SU-8

We describe an approach to use the thin layer of SU-8 submicron pattern produced by holographic lithography as dry etching mask in chemically assisted ion beam etching (CAIBE) system. The effect of chlorine gas flow on etched sidewall was investigated; by matching the lateral etch and deposition rate, etching selectivity of about 7:1 has been achieved with vertical and smooth sidewall and damage-free upper portion of the etched structure. As an application, a half wavelength retardation plate for 1.55 mm wavelength was designed, fabricated and characterized.
On the use of synthesis inhibitors to estimate brain norepinephrine synthesis in gonadectomized rats.

Brain norepinephrine synthesis rate in gonadectomized and control rats treated with alpha-methyl paratyrosine
Patterns of occurrence of reptiles across a sand dune landscape.

Identifying variables that drive population dynamics is a critical component of conservation and guides decisions for maintaining sustainable populations. Our objective was to model spatial and temporal patterns of occurrence of reptiles across an aeolian sand landscape. We used a community framework based on dune geomorphology and wind-precipitation gradients to identify variables that explain patterns of reptile abundance. We found that although population dynamics in arid environments are typically correlated with precipitation, in some instances that pattern was weak or absent. Strong precipitation-related abundance patterns were found with Coachella Valley fringe-toed lizards (Uma inornata), and zebra-tailed lizards (Callisaurus draconoides). The strength of that relationship varied along a precipitation gradient. We found weak or no precipitation relationships with long-lived, territorial species such as desert iguanas (Dipsosaurus dorsalis) and with species foraging on detritivore insects which appeared to not correlate with rainfall. In addition to precipitation our analyses allowed us to identify the influences of sand compaction, shrub density and exotic plant species, and how they varied between species and communities. Our approach broke down the inherent landscape complexity into tractable units that yielded information directly applicable to land managers and to the conservation of the species that comprise these communities.
An empirical comparison of consumer usability preferences in online shopping using stationary and mobile devices: results from a college student population

To determine the differences in user preferences between electronic and mobile commerce in consumer shopping, a 25-item survey concerning usability aspects of the two media was implemented on one hundred and eighteen college e-shoppers with experience in mobile devices. The Mobile Commerce Comparison Survey (MCCS) had four validated comparison factors: human factors-related, interface features, product-, and service-related factor. The comparison concludes that usability issues are perceived to be behind in m-commerce, and that m-commerce should be a shopping medium complementary to classic e-commerce rather than a direct alternative to it. Future studies may include empirical usability experiments for m-commerce tasks.
Simple, Rapid, and Micro High-Pressure Liquid Chromatographic Determination of Endogenous “True” Creatinine in Plasma, Serum, and Urine

Abstract Previously published methods for endogenous creatinine levels in plasma, serum, or urine lack specificity or are subject to interferences from endogenous or exogenous substances. The developed simple, rapid, and specific high-pressure liquid chromatographic method includes the novel deproteinization and extraction of 1 volume of plasma or serum with 2.5 volumes of acetonitrile and also of 1 volume of urine with 40 volumes of a 20% water-80% acetonitrile solution. An aliquot of the supernate is then injected directly into the chromatograph. A cation-exchange column and acidified (0.02% of 85% phosphoric acid) 0.1 M ammonium phosphate solution as the mobile phase, with a flow rate of 2 ml/min, were used. Creatinine, with a retention time of 3.8 min, was monitored via its UV absorption at 215 nm. Both peak height and integrated area methods of quantitation yielded the same results. Several methods were employed to show that the “suspected” creatinine peak from plasma samples was due entirely to the “true” creatinine. No interference was found in samples obtained from normal and renal patients. The day-to-day variation in the detector response was small. Each assay requires only about 5 min for completion. Ten microliters of plasma or serum or 1 μ l of urine is sufficient for analysis.
Membrane effects of ethanol: bulk lipid versus lipid domains.

It has been well-established that ethanol fluidizes the bulk lipid of membranes and that this effect may alter cell function and be involved in ethanol sensitivity and tolerance. This hypothesis has been supported in several studies, however, there is also a considerable amount of data that do not support such an explanation, e.g., direct effect of ethanol on proteins, other membrane acting drugs, temperature effects, effects of ethanol on aged membranes and inconsistent effects of chronic ethanol consumption on lipid content. This review examined the bulk membrane fluidization hypothesis in light of those data and proposed a modification of the bulk membrane hypothesis that is based on recent data that show that ethanol and other alcohols have a specific effect on the structural properties of different membrane domains. This specific effect of ethanol is discussed within the context of how changes in fluidity of domains may alter membrane function.
Integral analysis of planar and axisymmetric steady laminar buoyant diffusion flames

Momentum and energy integral analysis of planar and axisymmetric laminar, buoyant diffusion flames is presented with the objective of describing the flame properties and ambient air entrainment. The analysis follows the traditional momentum/energy integral technique utilizing the Howarth-Dorodnitzyn transformation for variable density flows and description of the velocity profiles through the flame region in the transformed constant-density coordinate system. The assumptions utilized in the formulation include the boundary layer and thin-flame approximations, a Prandtl and Schmidt number of unity and the product of molecular diffusivity-density squared being constant throughout the field. It is shown that a similarity solution exists for a vertical planar flame formed between a semi-infinite region of fuel in contact with a semi-infinite region of oxidizer and the results are presented in non-dimensional form in this case and are compared with their asymptotic values. For the steady laminar axisymmetric b...
An experimental study of the parametric excitation of a tensioned sheet with a cracklike opening

The problem of the parametric excitation of a thins tensioned sheet with a cracklike opening is discussed Data obtained from an experimental investigation are presented and they indicated that both principal and secondary regions of instability are developed. Plts of the stability boundaries are presented in terms of excitation frequency, mean tensile load and alternating load. The principal region is observed to be significantly larger than the secondary region and the amplitudes of the oscillations associated with the principal region are also much larger than those of the secondary region. Oscillation amplitudes of the order of twelve times the thickness are reported and amplitude vs. excitation-frequency data are shown to exhibit an overhang behavior in the direciton of increasing frequency. This indicates the presence of a nonlinear stiff effect which is attributed to middle-surface stretching due to bending. Although damping and membrane effects were found to prevent the development of unbounded oscillations, it is noted that the large deflections associated with the principal region of instability could be expected to have a deterious effect on both crack nucleation and crack propagation.
Sample size calculation based on efficient unconditional tests for clinical trials with historical controls

In historical clinical trials, the sample size and the number of success in the control group are often considered as given. The traditional method for sample size calculation is based on an asymptotic approach developed by Makuch and Simon (1980). Exact unconditional approaches may be considered as alternative to control for the type I error rate where the asymptotic approach may fail to do so. We provide the sample size calculation using an efficient exact unconditional testing procedure based on estimation and maximization. The sample size using the exact unconditional approach based on estimation and maximization is generally smaller than those based on the other approaches.
Management of Newly Privatized Companies: Its Importance and How Little We Know

Abstract Despite the extensive privatization efforts throughout the world since 1980, state-owned enterprises still contribute a significant share of GDP of many countries. Both developing and developed countries are committed to further reduce the role of their state sector and to stimulate efficiency in their economies. Privatization is, and will continue to be, an important and major activity in this process. Successful privatization however, requires sound management policies on the part of newly privatized industries. In order to ensure the success of privatization, more attention should be paid to the reforms in management and in governance of newly privatized industries.
Photoelectrolysis of water in semiconductor septum electrochemical photovoltaic cells

Abstract Producing hydrogen from water has been the dream of generations of energy-conscious scientists and engineers. That dream may at last be realized in the semiconductor septum electrochemical photovoltaic (SC-SEP) cell, which is modeled after nature's photosynthetic thylakoid membrane. The novel SC-SEP cell arose from studies of pigmented bilayer lipid membranes. The cell is easy to construct and simple to operate. It appears to offer a practical approach to the photochemical conversion and storage of solar energy. This report will describe how hydrogen is produced from artificial sea water when an SC-SEP cell is irradiated by the visible light of the solar spectrum.
Effect of dynamic stall on helicopter trim and flap-lag response

A unified lift model is used in the derivation of elastic blade equations. The resultant mathematical model predicts the aerodynamic forces on the helicopter blade and the flap-lag response before and after stall occurs. An ordering scheme is applied during the derivation so that only important terms are retained. The time history solution is obtained using Galerkin's method. The results agree qualitatively with the linear model for small angles of attack, and give a reasonable prediction of the flap-lag response including stall.
Embedded resistors and capacitors for organic-based SOP

System-on-package (SOP) architectures take advantage of compact, high-performance designs to place the maximum amount of functionality on a subsystem that can then be mounted on a lower-cost, lower density interconnect board. Embedding passive components is a key technology in achieving these goals since this enables smaller SOP substrate footprints or, equivalently, higher functional density, along with better power distribution, increased design flexibility and improved reliability. The resulting footprint areas of integrating capacitors will have more of an effect on the layer count of SOP assemblies than will integrating resistors due to the rather low specific capacitances of most embeddable dielectrics, but the situation is improving steadily. It may be necessary to use two different dielectric materials to cover the entire required range. The inherently lower parasitic inductance of embedded capacitors makes them much more useful in decoupling than surface mount capacitors, enabling more robust power distribution and decreased power/ground noise. The key to this performance enhancement in large boards is the use of a thin dielectric to decrease the inductance but, for the smaller SOP substrates, the dielectric constant must also be high to provide sufficient decoupling capacitance in the reduced area.
Grandparents and Grandchildren: An Often Neglected Relationship Between Significant Others.

The author discusses the grandparent-grandchild relationship and its implications for counseling activities. The historical and contemporary role expectations of grandparents and grandchildren, the reciprocal significance of this relationship, and ways to use the relationship in counseling services and programming in various settings are reviewed.
Ice and Steel - A Comparison of Creep and Failure

A structural theory that includes the mechanisms of intergranular crack initiation, crack multiplications and crack-enhanced matrix creep at high homologous temperatures, originally developed for polycrystalline ice, is presented and discussed in terms of available data on steels used for high-temperature applications. The model relates the macroscopic creep properties to the average microscopic characteristics that can be determined independently. It is shown that experimental results that include metallographic observations related to the embrittlement processes in both ice and steel are comparable and, in many instances, complementary. Grain size has been shown to play a major role in determining the overall creep response and damage accumulation, and thereby makes the model useful in understanding the response of heat affected zones in weldments in steels.
Alcohol consumption and endometrial cancer risk : The Multiethnic Cohort

The role of alcohol intake in the etiology of endometrial cancer is unclear. We examined the impact of alcohol intake on endometrial cancer risk among 41,574 postmenopausal African-American, Japanese-American, Latina, Native-Hawaiian and White women recruited to the prospective Multiethnic Cohort Study in 1993–1996. During an average of 8.3 years of follow-up, 324 incident invasive endometrial cancer cases were identified among these women. Data on alcohol intake and endometrial cancer risk factors were obtained from the baseline questionnaire. Relative risks (RRs) and 95% confidence intervals (CIs) for endometrial cancer associated with alcohol intake were estimated using log-linear (Cox) proportional hazard models stratified by age, year of recruitment, ethnicity and study center, and adjusted for several confounding factors. Increased alcohol consumption was associated with increased risk (p trend = 0.013). Compared to non-drinkers, women consuming ≥2 drinks/day had a multivariate RR of 2.01 (95% CI: 1.30, 3.11). There was no increase in risk associated with <1 drink/day (RR = 1.01; 95% CI: 0.77, 1.33) and 1 to <2 drinks/day (RR = 1.09; 95% CI: 0.62, 1.93). There was no clear effect modification by body mass index, postmenopausal hormone use, parity, oral contraceptive use or smoking status, though our power to detect such interactions was limited. Our results suggest that only alcohol consumption equivalent to 2 or more drinks per day increases risk of endometrial cancer in postmenopausal women.
Holographic data storage systems implemented with photorefractive materials

In this paper, we review the state-of-the-art in holographic data storage, with particular emphasis on the interplay between materials and systems issues. In a generic configuration, a reference and object beam are incident on a recording medium. Electronic digital bit streams are impressed onto a laser beam via a spatial light modulator (SLM) in the form of 2-D digital bit patterns or pages. Multiple pages are superimposed in a stack by angular, phase or wavelength encoding in the Fourier domain. The total recording volume is addressed by scanning both writing beams across the surface of the storage medium. Readout in each stack is achieved by capturing the reconstructed bit pattern on a CCD or other suitable detector array. The medium may consist of a monolithic single crystal or a mozaic of fibers ordered in a regular pattern. >
A fraction of tubercle bacilli possessing primary toxicity.

Tubercle bacilli separated from young cultures were thoroughly extracted with monochlorobenzene at temperatures never exceeding 50°C. From the soluble material, a fraction corresponding to approximately 1 per cent of the total bacillary weight was separated by fractional precipitation with petrolic ether at temperatures of 0° or 4°C.—depending upon the strain of bacilli. The monochlorobenzene-soluble-ether-insoluble material (fraction 7) prepared from BCG-P was found to contain 0.14 per cent nitrogen and 0.4 per cent phosphorus. Some of its other chemical characteristics are described. Fraction 7 proved unable to elicit tuberculin allergy in guinea pigs, but injection of 5 µg. of it into the skin produced severe local reactions. In albino mice, a single intraperitoneal injection of 20 µg. caused loss of muscular tone and of weight followed by death within 9 days. The only tissue reaction observed was a slight degree of peritonitis. In mice of the C57 BL strain, a single injection of 40 µg. also caused death in the same time, but with pulmonary hemorrhages—usually massive. Material similar to fraction 7 was obtained from one virulent, two attenuated, and one avirulent strain of mammalian tubercle bacilli (bovine and human). The fractions obtained from the various strains differed somewhat in solubility and toxicity. The more virulent the culture, the more toxic was the fraction obtained from it; but it is possible that this relation was the result of differences in the effectiveness of the extraction procedures, rather than of characteristics inherent to the cultures. Evidence is presented that the toxicity of fraction 7 accounts for much of the primary toxicity of tubercle bacilli.
Temperature-dependent modeling of gallium arsenide MESFETs

A complete temperature-dependent small signal model extraction methodology is used to achieve accurate circuit level simulations of metal semiconductor field-effect transistor (MESFET) amplifier performance over temperature. The procedure applies a previously described field-effect transistor (FET) modeling approach to predict the performance of a small signal amplifier over a -55/spl deg/C to 100/spl deg/C temperature range. This work includes a description of the MESFET equivalent circuit element thermal coefficients along with an amplifier simulation. Therefore, for the first time, a clear correspondence between circuit level simulation and measured results over temperature are published together. A new comparison of published temperature-dependent data shows a common agreement for amplifier gain variations of 0.015 dB//spl deg/C/Stage for a broad range of designs from 400 K down to cryogenic levels (77 K).
Expression of Human α(1,3)Fucosyltransferase Antisense Sequences Inhibits Selectin-mediated Adhesion and Liver Metastasis of Colon Carcinoma Cells

The initial steps of leukocyte and tumor cell adhesion involve selectin receptor/ligand interactions. The selectin ligand components sialyl Lewis x and sialyl Lewis a are oncodevelopmental antigens involved in progression of adenocarcinoma. Interrupting biosynthesis of these surface glycans by inhibition of alpha(1,3)fucosyltransferase (FUT) gene expression is an attractive goal for functional and therapeutic studies. We report here the inhibition of E-selectin-mediated adenocarcinoma cell adhesion by stable transfection of antisense sequences directed at the human Lewis alpha(1,3/1,4)fucosyltransferase gene, FUT3. The metastatic parental cell line, HT-29LMM, expressed high levels of sialyl Lewis x, sialyl Lewis a, alpha(1,3/1,4)fucosyltransferase activity, and FUT3 transcript, but antisense transfectant cell lines did not. When injected into the spleens of nude mice, the stable antisense clones were unable to colonize the liver. These results provide target validation for inhibition of carcinoma metastasis with antisense FUT sequences and confirm the primacy of alpha(1,3)fucosyltransferases in the synthesis of selectin ligands.
Robust representations of cortical speech and language information

Cortical recordings with high temporal resolution enable the tracking of neuronal excitation in response to stimuli. Here intra and extracranial recordings are analyzed from experiments presenting varied speech and language stimuli to human subjects. These studies demonstrate that information about speech and language is widely distributed across the brain, both spatially and temporally. Analyses using machine learning techniques can be used to track the space and time-course of performance in recognizing different words (83% on 10 spoken words), semantic categories (76% on 2 categories), etc.
Combining two media access protocols to support integrated traffic on high data rate networks

The paper describes the operation and performance of an integrated traffic network using separate media access protocols to support different traffic types on a single unidirectional ring or bus. One protocol, based upon local carrier sensing (CSMA/RN) provides access for asynchronous traffic; the other, a 'train like' protocol called the circulating reservations packets (CRPs), provides access for synchronous voice and video traffic. Other media access protocols like slotted ring or QPSX are equally applicable for use as the asynchronous protocol. >
Prognostic Implications of Absolute and Relative Calcium Scores

The continuing epidemic of cardiovascular disease underscores the need for more effective atherosclerosis detection and prevention. In fact, though the mortality rate decreased during the past decades, the morbidity rate continued to climb. The use of conventional risk factors is helpful to assess the median risk of a population, but it is unsatisfactory to estimate the actual risk of an individual patient.
Ultra high f/sub max/ InP/InGaAs/InP transferred substrate DHBTs

Very wide bandwidth double heterojunction bipolar transistors (DHBT) will enable high-power amplifiers at 94 and 180 GHz, microwave ADCs, microwave direct digital frequency synthesis, fiber optic transmission at >40 Gb/s and wireless data networks at frequencies above 100 GHz (M. Rodwell et al, IEEE GaAs IC Symp. Tech. Dig., pp. 113-117, 1998). To realize such ICs, transistors with high breakdown voltage, very high current gain cut-off frequency f/sub t/ and very high power gain cut-off frequency f/sub max/ are essential. Transferred substrate single heterojunction bipolar transistors (SHBTs) have demonstrated very high bandwidth and are potential candidates for very high speed integrated circuit applications (Q. Lee et al, IEEE Electron Dev. Lett., vol. 19, pp. 77-79, 1998; Q. Lee et al, ibid., vol. 20, no. 8, pp. 396-398, 1999). The transferred substrate SHBTs, however, have very low breakdown voltage, BV/sub CEO/∼1.5 V. Here we report transferred-substrate DHBTs with emitter junction widths as small as 0.3 μm for the emitter and 1.0 μm for the collector. These exhibit a record 462 GHz f/sub max/.
Diffusion MRI in three types of anoxic encephalopathy

We report the clinical and diffusion-weighted MRI (DWI) features of three patients with different types of anoxic brain injury: attempted hanging (hypoxic hypoxia), carbon monoxide poisoning (histotoxic hypoxia), and hanging with cardiac arrest (hypoxic-ischemic encephalopathy, HIE). The first two patients, but not the third, recovered substantial neurological function. The distribution of DWI abnormalities was different and correlated well with the distinct neuropathological features of these entities. The prognosis after anoxic encephalopathy depends on the underlying mechanism and its severity, which may be reflected by DWI abnormalities.
Single Ventricle Reconstruction Trial: A Work in Progress

Hypoplastic left heart syndrome, which occurs in 1 per 5000 live births, refers to a family of cardiac defects that are characterized by hypoplasia of the structures making up the left side of the circulation, including the mitral and aortic valves, the left atrium and left ventricle, and the aorta. Infants with this syndrome typically undergo a 3-stage surgical palliation. Without this surgery, the defect is lethal. Since the report of the first Norwood procedure1 for hypoplastic left heart syndrome by Dr William Norwood in 1981, results from treatment of hypoplastic left heart syndrome have improved considerably. In a large single-center report, operative mortality associated with the first-stage procedure was reduced from 59% to 19% between 1990 and 2001.2 Nonetheless, the complete palliative sequence entails 3 surgeries and has considerable interstage mortality, so the overall survival for patients with hypoplastic left heart syndrome remains poor. Article see p 2013 In 2003, a major modification of the classic Norwood stage 1 procedure was introduced, substituting a shunt from the right ventricle to the pulmonary artery (RVPA) for the traditional modified Blalock-Taussig shunt (MBT) that carries blood from the brachiocephalic artery to the pulmonary artery.3 There are several theoretical advantages to the RVPA shunt, stemming from the absence of diastolic blood flow from the systemic circulation to the pulmonary circulation. These include increased coronary flow, enhanced postoperative stability, and reduced interstage mortality. …
Infants' detection of contingency: a cognitive-neuroscience perspective.

Abstract Advances in developmental cognitive neuroscience have generated important and interesting data that are relevant to infants' perception of contingencies. The author discusses concepts of “binding” (i.e., the binding of stimulus properties across space, and binding of events across time) within the context of the cognitive-neuroscience approach to learning. Issues relevant to infant contingency perception are also addressed. Previously published data on infant contingency perception and discrimination learning from the author's laboratory are reinterpreted in terms of these binding concepts, as well as the development of the neural substrates that presumably underlie the perception of stimulus attributes and temporal redundancy.
Reducing Einstein’s Equations to an Unconstrained Hamiltonian System on the Cotangent Bundle of Teichmüller Space

A program for reducing Einstein’s vacuum equations to an unconstrained dynamical system where the variables are the true degrees of freedom of the gravitational field is presented. The reduced phase space on which this dynamics occurs is the cotangent bundle T*Tof $$ \mathcal{T} \equiv \frac{{\mathcal{M}/\mathcal{P}}}{{{{\mathcal{D}}_{0}}}} $$ the D o-restricted conformal superspace of a compact connected orientable 3-manifold M, which we also refer to as the Teichmuller space of conformal structures on M. From results regarding linearization stability of spacetimes, we argue that the program of reduction should be successful for spacetimes that admit constant mean curvature continuously non-symmetric (or deg(M) = 0) non-F6 compact spacelike Cauchy hypersurfaces, inasmuch as the space of solutions to Einstein’s equations is a manifold in a neighborhood of such spacetimes. Modulo the Poincare conjecture and a conjecture regarding finite free actions on S3, the topological types of all such spacelike Cauchy hypersurfaces M are identified.
MIT-Skywalker

The ability to walk is important for independent living and when this capacity is affected by neurological injury, gait therapy is the traditional approach to re-train the nervous system. The importance of this problem is illustrated by the approximately 5.8 million stroke survivors alive in the US today and an estimated additional 700,000 strokes occurring each year, many requiring gait therapy. This manuscript presents the design and proof-of-concept testing for a novel device to deliver gait therapy. While robotic devices to train gait therapy exist, none of them take advantage of the concept of passive walkers and most of them impose the kinematics of unimpaired gait on impaired walkers. Yet research has found that proper neural input and stimulation is a critical factor for an efficacious therapy program. This novel device might afford a more ecological gait therapy including heel-strike.
Covalent Thiol Adducts Arising from Reactive Intermediates of Cocaine Biotransformation

Exposure to cocaine results in the depletion of hepatocellular glutathione and macromolecular protein binding in humans. Such cocaine-induced responses have generally been attributed to oxidative stress and reactive metabolites resulting from oxidative activation of the cocaine tropane nitrogen. However, little conclusive data exists on the mechanistic pathways leading to protein modification or the structure and specificity of cocaine-derived adduction products. We now report a previously uncharacterized route of cocaine bioactivation leading to the covalent adduction of biological thiols, including cysteine and glutathione. Incubation of cocaine with biological nucleophiles in an in vitro biotransformation system containing human liver microsomes identified a monooxygenase-mediated event leading to the oxidation of, and subsequent sulfhydryl addition to, the cocaine aryl moiety. Adduct structures were confirmed using ultra-high performance liquid chromatography coupled to high resolution, high mass accu...
Distributed and Dynamic Neural Encoding of Multiple Motion Directions of Transparently Moving Stimuli in Cortical Area MT.

Segmenting visual scenes into distinct objects and surfaces is a fundamental visual function. To better understand the underlying neural mechanism, we investigated how neurons in the middle temporal cortex (MT) of macaque monkeys represent overlapping random-dot stimuli moving transparently in slightly different directions. It has been shown that the neuronal response elicited by two stimuli approximately follows the average of the responses elicited by the constituent stimulus components presented alone. In this scheme of response pooling, the ability to segment two simultaneously presented motion directions is limited by the width of the tuning curve to motion in a single direction. We found that, although the population-averaged neuronal tuning showed response averaging, subgroups of neurons showed distinct patterns of response tuning and were capable of representing component directions that were separated by a small angle—less than the tuning width to unidirectional stimuli. One group of neurons preferentially represented the component direction at a specific side of the bidirectional stimuli, weighting one stimulus component more strongly than the other. Another group of neurons pooled the component responses nonlinearly and showed two separate peaks in their tuning curves even when the average of the component responses was unimodal. We also show for the first time that the direction tuning of MT neurons evolved from initially representing the vector-averaged direction of slightly different stimuli to gradually representing the component directions. Our results reveal important neural processes underlying image segmentation and suggest that information about slightly different stimulus components is computed dynamically and distributed across neurons. SIGNIFICANCE STATEMENT Natural scenes often contain multiple entities. The ability to segment visual scenes into distinct objects and surfaces is fundamental to sensory processing and is crucial for generating the perception of our environment. Because cortical neurons are broadly tuned to a given visual feature, segmenting two stimuli that differ only slightly is a challenge for the visual system. In this study, we discovered that many neurons in the visual cortex are capable of representing individual components of slightly different stimuli by selectively and nonlinearly pooling the responses elicited by the stimulus components. We also show for the first time that the neural representation of individual stimulus components developed over a period of ∼70–100 ms, revealing a dynamic process of image segmentation.
A probabilistic approach for lateralization of seizure onset zone in drug-resistant epilepsy with bilateral cerebral pathology

Abstract Background Lateralization of seizure-onset zone (SOZ) during electroencephalography (EEG) monitoring in people with bilateral potentially epileptogenic lesions is important to facilitate clinical decision making for resective surgery. Methods We develop two Bayesian approaches for estimating the number of consecutive ipsilateral seizures required to lateralize the SOZ to a given lower limit of 95% credible interval (LLI, assuming continuous prior distribution), or to a given posterior probability (assuming mixture of discrete and continuous prior probabilities). Results With estimation approach, if both the cerebral hemispheres are a priori equi-probable to contain SOZ, then using Jeffrey's prior, a minimum of 9, 18, and 38 consecutive ipsilateral seizures will yield an LLI of 0.81, 0.90, and 0.95 respectively. If one of the hemisphere is a priori more likely to have SOZ, then prior beta distributions with α = 3, β = 2, and α = 4, β = 3 will require a minimum of 18 and 24 consecutive ipsilateral seizures to yield an LLI of 0.80. Contrariwise, the testing approach allows approximation of the number of consecutive ipsilateral seizures to lateralize the SOZ depending on an estimate of prior probability of lateralized SOZ, to a desired posterior probability. For a prior probability of 0.5, using uniform prior, mixture model will require 7, 17, and 37 consecutive ipsilateral seizures to lateralize the SOZ with a posterior probability of 0.8, 0.9, and 0.95 respectively. Conclusion While the reasoning presented here is based on probability theory, it is hoped that it may help clinical decision making and stimulate further validation with actual clinical data.
The Underlying Role of Negative Affect in the Association between PTSD, Major Depressive Disorder, and Generalized Anxiety Disorder

Clinicians and researchers have found differential diagnosis to be difficult, particularly for conceptually similar disorders. One category of particular interest has been distress or internalizing disorders, theorized to be related via an underlying construct of generalized distress or negative affect. The present study attempted to address the comorbidity of three distress disorders - posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) - using latent analyses by controlling for the variance attributable to negative affect. The sample consisted of 265 trauma-exposed individuals who completed self-report measures of PTSD, MDD, GAD, and negative affect. Confirmatory factor analysis was used to test initial model fit. Next, the model was re-computed, controlling for negative affect by regressing negative affectivity at the item-level. Results indicated that a significant amount of variance within and between these diagnostic categories is attributable to negative affect at both the item- and factor-level. The hypothesis that MDD’s non-somatic/affective factor and the GAD factor would have the highest attenuations in factor loadings after controlling for negative affect was supported. Therefore, negative affect significantly influences the co-occurrence of PTSD, MDD, and GAD clinically, emphasizing the need for transdiagnostic interventions for trauma victims.
A Tale of Two Sources in Native Advertising : Examining the Effects of Source Credibility and Priming on Content,Organizations, and Media Evaluations

In the strategic communication field, native advertising has been hailed as the next big trend. However, this type of marketing technique may negatively affect the perceptions of brands as well as ...
Plasticity in incubation behavior and shading by king rails (Rallus elegans) in response to temperature

King rails experience a wide range of temperatures during the course of the breeding season throughout their rapidly contracting geographic range. Incubating parent birds are adapted to keep their eggs within a temperature range appropriate for embryo development, but king rail clutches are at risk of exceeding lethal temperatures in the latter half of the nesting season. We investigated whether behavioral plasticity during incubation enables parents to maintain clutch temperature within tolerable limits for embryo development. Video revealed that king rail parents interrupted incubation to stand above and shade their eggs. We tested the hypothesis that the onset of shading was a direct response to ambient temperature (adaptive plasticity). We monitored clutch temperature directly by experimentally adding into clutches a model egg embedded with a programmable iButton. We measured ambient temperature at the nest site simultaneously. Parents spent proportionately more time shading and less time incubating their eggs at higher ambient temperatures. Shading may primarily function in cooling the parent. The frequency and duration of shading bouts were significantly greater at higher ambient temperatures. Parents also took more frequent but shorter recesses in hotter conditions. Diurnal recesses exposed eggs to direct sunlight, and the highest clutch temperatures were recorded under these conditions. Complete hatching failure in at least one nest was attributable to high clutch temperature for an extended period. Because mean ambient temperature increases throughout the breeding season, we investigated seasonal patterns in onset of incubation and its effect on hatching rate. Later in the season, parents tended to initiate incubation earlier, and hatching asynchrony increased significantly. Together these results suggest that breeding king rails may be constrained in their ability to cope with sustained high temperatures should seasonal averages continue to rise as predicted. This article is protected by copyright. All rights reserved.
Knowledge of and Preparedness for Use of Environmental Assessments in Shelters During Disasters: Results of the 2013 State and Territorial Use of Shelter Assessments Survey.

OBJECTIVE: Environmental health assessments of disaster shelters are critical for monitoring the living conditions of the occupants. However, knowledge and levels of utilization of these assessments have never been estimated in the United States or its territories. We aimed to conduct a cross-sectional survey to ascertain knowledge and Utilization of environmental health disaster shelter assessments. METHODS: The State and Territorial Use of Shelter Assessments Survey (STUSA) of environmental health department directors (N=56) was carried out in 2013. RESULTS: Survey responses were received from 55 of 56 targeted jurisdictions. Of those respondents, 92% of state jurisdictions and 100% of territories reported having knowledge about shelter assessments. However, only 40% of states and 60% of territories reported receiving formal training, and 53% of states and 50% of territories reported having operational procedures for shelter assessments. High levels of knowledge and familiarity and low levels of training and processes for operationalizing assessments were assessed. CONCLUSIONS: Because environmental health assessments may provide useful information in disaster settings, we need to understand the barriers to their implementation. The results of these assessments may also help to validate their usefulness in protecting shelter occupants during disasters. (Disaster Med Public Health Preparedness. 2016;page 1 of 4). Language: en
Context is Everything

Sociologist and food critic Joshua Page talks with New York Times food critic about the sociological work of reviewing restaurants.