cssi/SciSciGPT-SciSciNet huggingface dataset:
Reflections on research and the future of medicine.

Drawings used to illustrate replication of the DNA molecule [ 153 , 445 (22 July 1966)] were from the forthcoming book, The New Genetics , by the late Leonard Engel. Mr. Engel, a well- known science writer, was the author of The Operation, The Medicine Makers of Kalamazoo , and The Sea. The New Genetics is being edited by Edward Tatum and will be published by Doubleday early in 1967.
Influence of global atmospheric change on the feeding behavior and growth performance of a mammalian herbivore, Microtus ochrogaster.

Global atmospheric change is influencing the quality of plants as a resource for herbivores. We investigated the impacts of elevated carbon dioxide (CO2) and ozone (O3) on the phytochemistry of two forbs, Solidago canadensis and Taraxacum officinale, and the subsequent feeding behavior and growth performance of weanling prairie voles (Microtus ochrogaster) feeding on those plants. Plants for the chemical analyses and feeding trials were harvested from the understory of control (ambient air), elevated CO2 (560 m lC O2 l 21 ), and elevated O3 (ambient 6 1.5) rings at the Aspen FACE (Free Air CO2 Enrichment) site near Rhinelander, Wisconsin. We assigned individual voles to receive plants from only one FACE ring and recorded plant consumption and weanling body mass for seven days. Elevated CO2 and O3 altered the foliar chemistry of both forbs, but only female weanling voles on the O3 diet showed negative responses to these changes. Elevated CO2 increased the fiber fractions of both plant species, whereas O3 fumigation elicited strong responses among many phytochemical components, most notably increasing the carbon-to-nitrogen ratio by 40% and decreasing N by 26%. Consumption did not differ between plant species or among fumigation treatments. Male voles were unaffected by the fumigation treatments, whereas female voles grew 36% less than controls when fed O3-grown plants. These results demonstrate that global atmospheric change has the potential to affect the performance of a mammalian herbivore through changes in plant chemistry.
Identification of a selenocysteine-specific aminoacyl transfer RNA from rat liver

The aminoacylation of rat liver tRNA with selenocysteine was studied in tissue slices and in a cell-free system with [75Se]selenocysteine and [75Se]selenite as substrates. [75Se]Selenocysteyl tRNA was isolated via phenol extraction, 1 M NaCl extraction and chromatography on DEAE-cellulose. [75Se]Selenocysteyl tRNA was purified on columns of DEAE-Sephacel, benzoylated DEAE-cellulose and Sepharose 4B. In a dual-label aminoacylation with [35S]cysteine, the most highly purified 75Se-fractions were greater than 100-fold purified relative to 35S. These fractions contained less than 0.7% of the [35S]cysteine originally present in the total tRNA. When [35Se]selenocysteyl tRNA was purified from a mixture of 14C-labeled amino acids, over 97% of the [14C]aminoacyl tRNA was removed. The [75Se]selenocysteine was associated with the tRNA via an aminoacyl linkage. Criteria used for identification included alkaline hydrolysis and recovery of [75Se]selenocysteine, reaction with hydroxylamine and recovery of [75Se]selenocysteyl hydroxamic acid and release of 75Se by ribonuclease. The specificity of [75Se]selenocysteine aminoacylation was demonstrated by resistance to competition by a 125-fold molar excess of either unlabeled cysteine or a mixture of the other 19 amino acids in the cell-free selenocysteine aminoacylation system.
Frequency measurement methods and impact in presence of frequency responsive loads and distributed energy resources

Frequency monitoring on the power system is used to balance load and generation, as load increases the frequency value decrease and as generation increases the frequency values increases. Under normal operation the frequency is maintained between 59.98Hz and 60.02Hz in a 60Hz system. Today the balance between load and generation is achieved by controlling generation only [1]. However, as more load control is being introduced to the power system, using the frequency value to turn on and off frequency responsive loads present a mechanism to provide regulation as well [2]. This method relies on local frequency measurement and local trigger set point. This paper illustrates the impact of frequency measurement on frequency responsive load application and on protection devices in presence of distributed generation.
The effect of anionic polyelectrolytes on the crystallization of calcium oxalate hydrates

Abstract Calcium oxalate was precipitated from supersaturated calcium oxalate solutions in the presence of different water soluble polymers: poly(acrylic acid), poly(methacrylic acid), poly(styrene sulfonate-alt-maleic anhydride), poly(maleic anhydride), and poly(vinyl sulfonate). The supersaturated solutions were made with initial calcium and oxalate concentrations of 4×10 -3 M and 1.5×10 -3 M respectively. In the presence of anionic polyelectrolytes there was a change in the hydrate from of calcium oxalate which precipitated. With low concentrations of polyelectrolyte (up to 1 ppm) only the monohydrate was formed, at intermediate concentration (1–50 ppm) trihydrate was the predominant product, and at high concentrations (above 50 ppm) the dihydrate form was the dominant product. Nonpolyelectrolytes had no effect on the crystallization and thus only calcium oxalate monohydrate was formed. This effect was found to occur with all polyelectrolytes used regardless of molecular weight or charge. The change from one hydrate from to another occured at a lower polymer concentration with the low molecular weight polymers.
Der Btx-Rechnerverbund und der IBM-PC als Btx-Endgerät

Der technologische Fortschritt offnet gerade im Bereich der Information und Kommunikation standig neue Chancen, zumindestens aber eine Vervollkommnnung bereits vorhandener Mittel und Methoden. Das Fernsehgerat und das Telefon sind bewahrte Kommunikationsmedien, die in den vergangenen Jahren standig verfeinert und verbessert wurden. Die Idee, beide miteinander und zudem mit den Moglichkeiten der Informationsverarbeitung zu verbinden, wie dies bei Bildschirmtext geschieht, ist neu (Abb. 1 s. Anhang).
Scattering of plane harmonic P, SV or Rayleigh waves by a completely embedded corrugated cavity

SUMMARY Scattering of plane harmonic P, SV or Rayleigh waves by a 2-D corrugated cavity completely embedded in an isotropic half-space or full-space is investigated by using a direct boundary integral equation method. The corrugated scatterer is generated by superimposing a sinusoidal perturbation of arbitrary amplitude and period to a smooth elliptical shape. Extensive testing of the numerical results is done through comparisons with analytical and numerical solutions for the corresponding smooth surface limits. The displacement field is evaluated along the half-space surface or the scatterer for a wide range of frequencies and corrugation shapes. The results clearly demonstrate the importance of the cavity roughness on the ensuing motion. The cavity response is found to strongly depend upon the corrugation amplitude and period as well as the frequency of the incident wave. For the half-space problem with a vertical P or SV incidence, the rough cavity far-field surface motion may attenuate differently from the free-field result than the corresponding smooth cavity response. In the near field, the corrugated response is found to be significantly different from the equivalent smooth cavity result. For an oblique P, SV or a Rayleigh incidence, the rough cavity motion at the illuminated portion of the half-space surface may be greatly different from the corresponding smooth cavity motion. In the shadow portion of the half-space, the presence of the corrugation may produce an important shielding effect in the surface motion. These key differences between the rough and smooth cavity responses are especially pronounced for shorter corrugation periods and at higher frequencies. In addition, a strong site effect is observed atop the rough cavity.
A practical approach to manage applications and prevent malware spreading in mobile environment

In this paper, we propose an App Quick Sieve/Verify Scheme (AQSVS) to improve the App safety/quality verification issue in the third-party or enterprise app market place. The concerns related to app store safety are of paramount interest as and an increasing number of malware and defective apps caused by Android fragmentation. The AQSVS based on the use of App package information and TF/IDF inverted index table to quick classify whether the app is a new app, an updated app or a repackaged app with a similarity scoring module and a testing engine to determine the app can be published or not. This solution improves the efficiency of the app testing process which is blocking the repackaged apps and apps with defects inside to publish in an app store.
NMR studies of fluorocarbon diphosphines and oxy- and thio-bisphosphines

Both the diphosphine CH3CF3PPCH3CF3 and the thio-bisphosphine CH3CF3PSPCH3CF3 show 19F and 31P NMR spectra indicative of diastereomeric mixtures of d,l and meso isomers. The temperature-dependent reversible interconversions of the isomers have been attributed to the inversion at the phosphorus atom. The equilibrium constants for the isomerization reactions have been measured at various temperatures. The fluorine NMR spectra of the meso and d,l isomers of CD3CF3PSPCD3CF3 have been analyzed as M3XX′M3′ spin systems. Good agreement is found between the observed and calculated spectra. The five-bond fluorine-fluorine coupling constant of the low-field isomer is larger than that of the high-field isomer. The 19F NMR spectra of (CF3)2PP(CF3)2, (CF3)2POP(CF3)2, (CF3)2PSP(CF3)2, CH3CF3PPCH3CF3 and CH3CF3PSPCH3CF3 have been examined over a wide range of temperatures in an attempt to correlate the data to the geometries of these compounds.
Convective self-assembly to deposit supported ultra-thin mesoporous silica films

For practical consideration in applying mesoporous films for sensors, it is ideal to fabricate thinner films to achieve fast transport and therefore rapid response. Here we report a new, facile method to deposit mesoporous silica films with thickness less than 100 nm through combining convective self-assembly and surfactant/silica self-assembly. Through an interfacial capillarity defined in the wedge between two substrates, a meniscus of solutions containing silicate, surfactant, alcohol, and water is formed. While the solvent evaporates during the film formation, the solution from the bulk droplet spreads to the drying region, enriching the surfactant/silica concentration at the edge of the meniscus by the convective flux of solvent. The continuous evaporation, spreading, and enriching induce surfactant and silica self-assembly in the bulk droplet to form an ordered surfactant/silica liquid crystal mesophase film. After calcination, supported ultra-thin films are formed containing interconnected mesopore channels with high surface areas. The combined self-assembly process relies on the evaporation of the solvents to form ordered mesostructures, which enables the deposition of patterned films and ultimately makes this combined technique ideal for device fabrication.
Temperature Effects in Photomultipliers and Astronomical Photometry

Temperature coefficients are reported for photomultiplier tube types used in astronomy. For 1% stability of gain and color response, temperature regulation of 1°C or better is generally required. This is nearly an order of magnitude better than what is usually achieved at the telescope, but careful use of a well-designed cold box should make 1°C temperature stability possible. For maximum stability and reproducibility, ordinary blue-sensitive tubes should be avoided at wavelengths longer than 5000 A, and trialkali cathodes should not be used beyond 6500 A.
Factors contributing to burnout among perfusionists in the United States

Introduction: As the job climate continues to change, many perfusionists are faced with high employee turnover rates, working longer hours, and increased stress related to more complex surgeries. Understanding the sources of profes- sional burnout and stress may allow the formulation of a strategy to help prevent such negative outcomes. The purpose of this study was to determine the current level of stress and burnout among perfusionists. Methods: A questionnaire was constructed with the use of SurveyMonkey®. Invitations requesting participation in the survey were distributed by electronic mail to members of PerfList and PerfMail. To assess burnout, components of the well-established Maslach Burnout Inventory (MBI) tool were used. Results: At p<0.05, job demand variables such as stress level, conflict, call duties, hours worked, and case load were all shown to have a statistically significant relationship to burnout. Conclusion: The study found that, among the various factors, job demands were the most likely culprit contributing to burnout. Stress level and conflict, in particular, had the strongest association to burnout.
Reduced Cytosolic Ca2+ Loading and Improved Cardiac Function After Cardioplegic Cold Storage of Guinea Pig Isolated Hearts

Background—Hypothermia is cardioprotective, but it causes Ca2+ loading and reduced function on rewarming. The aim was to associate changes in cytosolic Ca2+ with function in intact hearts before, during, and after cold storage with or without cardioplegia (CP). Methods and Results—Guinea pig hearts were initially perfused at 37°C with Krebs-Ringer’s (KR) solution (in mmol/L: Ca2+ 2.5, K+ 5, Mg2+ 2.4). One group was perfused with CP solution (Ca2+ 2.5, K+ 18, Mg2+ 7.2) during cooling and storage at 3°C for 4 hours; another was perfused with KR. LV pressure (LVP), dP/dt, O2 consumption, and cardiac efficiency were monitored. Cytosolic phasic [Ca2+] was calculated from indo 1 fluorescence signals obtained at the LV free wall. Cooling with KR increased diastolic and phasic [Ca2+], whereas cooling with CP suppressed phasic [Ca2+] and reduced the rise in diastolic [Ca2+]. Reperfusion with warm KR increased phasic [Ca2+] 86% more after CP at 20 minutes and did not increase diastolic [Ca2+] at 60 minutes, compare...
Smallest (1, 2)-eulerian weight and shortest cycle covering

The concept of a (1, 2)-eulerian weight was introduced and studied in several papers recently by Seymour, Alspach, Goddyn, and Zhang. In this paper, we proved that if G is a 2-connected simple graph of order n (n ≧ 7) and w is a smallest (1, 2)-eulerian weight of graph G, then |Ew=even | n - 4, except for a family of graphs. Consequently, if G admits a nowhere-zero 4-flow and is of order at least 7, except for a family of graphs, the total length of a shortest cycle covering is at most | V(G) | + |E(G) |- 4. This result generalizes some previous results due to Bermond, Jackson, Jaeger, and Zhang. © 1994 Wiley Periodicals, Inc.
Scattering by defects in an exponentially graded layer and misuse of the method of images

An inhomogeneous layer is sandwiched between homogeneous half-spaces. The layer contains a defect. There are incident waves and the problem is to calculate the scattered waves. Five recent publications are criticised, mainly because of their misuse of the method of images.
Nanoelectromechanics of Piezoresponse Force Microscopy: Contact Properties, Fields Below the Surface and Polarization Switching

Piezoresponse Force Microscopy (PFM) has become the primary tool for characterization and domain engineering in ferroelectric materials at nanoscale dimensions. To achieve quantitative interpretation of PFM, knowledge of elastic and electrostatic field distributions below the tip is required. The solution of the coupled electroelastic problem for piezoelectric indentation is derived and used to obtain the tipinduced electric field and strain distribution in the material. This establishes a complete continuum mechanics description of the PFM imaging mechanism. These rigorous solutions are reduced to a point charge/force behavior for large separations from contact and the applicability limits and charge/force magnitude for these models are established. Electroelastic field distributions provide a quantitative analysis of the PFM polarization switching processes and show the switching processes can be adequately described using point charge models. For high-order ferroelastoelectric, ferrobielectric and ferrobielastic switching processes the domain size is limited by the contact area, providing an approach to high-resolution ferroelectric lithography.
Diatomic-molecule model for a mixed-valence system

A model for a homopolar diatomic molecule is presented. It contains the following: (a) one $s$-like and one $f$-like orbital per atom, (b) an interatomic transfer term between the $s$ states, (c) an interatomic hybridization term between $s$ and $f$ states, (d) a very strong intra-atomic Coulomb repulsion between two $f$ electrons, and (e) an intra-atomic Coulomb repulsion between $s$ and $f$ electrons. The ground-state energy for the two-electron system is analyzed in detail for a variety of cases. The phenomenon of mixed valence is examined. It is found that the Coulomb interaction between $s$ and $f$ electrons tends to suppress the average occupation of $f$ states between values of one-third and one; depending on the other parameters, the occupation tends to take either values between zero and one-third or one, the full occupation.
Towards Computational Offloading in Mobile Device Clouds

Many mobile applications overcome their device limitations in computational, energy, or data resources by offloading computations to the cloud. In this paper, we consider environments in which computational offloading occurs amongst a set of mobile devices. We call such an environment a mobile device cloud (MDC). In this work, we first highlight the gain in computation time and energy consumption that can be achieved by offloading tasks to nearby devices within an MDC compared to a cloud. We then propose and implement an MDC platform that enables the creation and assessment of various offloading algorithms in MDCs. This platform consists of an Android application deployable across MDC devices, and a test bed to measure power being consumed by a mobile device. We utilize this platform to carry out various offloading experiments on an MDC test bed from which we gain interesting insights into the potential for MDC offloading. Results from these experiments show up to 50% gain in time and 26% gain in energy. Finally, we address the off loadee selection problem in MDCs by proposing several social-based algorithms. The potential promise of this approach is shown by evaluating these algorithms using real data sets that include contact traces and social information of mobile devices in a conference setting.
Bird Carousel for Environmental Chambers

Abstract SMALL, controlled environmental chambers where temperature, humidity, and light are closely regulated are becoming ever more common as a research tool for basic studies in poultry science. But what is a reasonable cage system in which to confine the birds so that the maximum use is made of minimum space, and all birds are given equal environmental exposure and equal opportunity to eat and drink? A system that has worked out most satisfactorily in the 1.37 meter wide by 2.77 meter long climatic chambers at the University of California, Davis, is the Bird Carousel, shown in Fig. 1. This multi-deck, interchangeable, multi-species turn-table for laboratory birds was economically built by Mr. Peter Backer, a Mechanician in the Department of Poultry Husbandry. The base is a welded iron frame; a small gearhead motor drives a vertical output shaft reduction gear box which in turn drives the carousel turntable. The turntable rotates…
Control of a drop ejector used as a photoresist dispenser

Photo-resist dispensers traditionally apply a generous amount of resist on the wafer and then spin the wafer to reach a uniform desired thickness. With this technique, over 95% of expensive and hazardous liquid is wasted. The goal of this project is to reduce the waste by using a drop-on- demand ejection technology to apply the photo-resist. In practice, a controller turns out to be necessary to compensate for the variability of the performance of the ejectors, to insure the stability of the ejection, and to speed up the transient regime for drop-on-demand operation. The paper reports on the design and simulation of this controller.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Excitonic Effects and the Optical Absorption Spectrum of Hydrogenated Si Clusters

We calculate the optical absorption spectrum of hydrogen-terminated silicon clusters by solving the Bethe-Salpeter equation for the two-particle Green{close_quote}s function using an {ital ab initio} approach. The one-particle Green{close_quote}s function and the electron-hole interaction kernel are calculated within the GW approximation for the electron self-energy operator. Very large exciton binding energies are observed. Our results for the one-particle properties and the optical absorption spectra of the clusters are in very good agreement with available experimental data. {copyright} {ital 1998} {ital The American Physical Society}
Proximate control of siblicide in cattle egrets: a test of the food-amount hypothesis

Avian sibling aggression plays an important role in controlling food distribution among nest mates. The food-amount hypothesis predicts that the amount of food obtained by siblings acts as a proximate cue controlling their level of aggression. The importance of this cue to cattle egrets (Bubulcus ibis) in Oklahoma was evaluated by studying parental feeding rates, food distribution among nestlings, and nestling aggression in three-chick broods [A-(oldest), B-, and C-chicks]. We compared nests in which siblicide occurred to nests where all three chicks survived (nonsiblicide nests). Relative to nonsiblicide nests, siblicide nests received decreasing amounts of food as the day of siblicide approached. Similarly, aggression levels of all three chicks in siblicide nests increased significantly compared with nonsiblicide nests, with most of the aggressive behavior involving B- and C-chicks. As a result, on a per-day basis, food amount and aggression exhibited a strong, negative correlation, thus providing support for the food-amount hypothesis. Though the total amount of food delivered to siblicide nests declined on the days prior to siblicide, the amount of food received by A-chicks in these nests did not. Relative to nonsiblicide nests, A-chicks in siblicide nests received an increased share (percent of volume) of the food delivered at the expense of C-chicks, with the percent remaining the same for B-chicks. The percentage of food B-chicks received the day after siblicide increased significantly from that received the day before siblicide, with no change occurring in either the amount or percentage of food received by A-chicks; clearly, B-chicks were the beneficiary of their aggressive actions that resulted in the death of C-chicks. We provide evidence supporting the hypothesis that aggression is proximately linked to food amount, possibly by a relatively simple cue such as hunger.
Drawing Lines in the Journalistic Sand: Jon Stewart, Edward R. Murrow, and Memory of News Gone By

In mid-December 2010, The Daily Show host Jon Stewart asked Congress to address the health care needs of 9/11 rescue workers—which it did. Shortly after, the New York Times published an analysis piece comparing Stewart to the legendary broadcaster Edward R. Murrow. This article explores how collective memory of Murrow was used by both mainstream media and the blogosphere to negotiate membership boundaries of journalism itself, with analysis conducted through textual analysis of online mainstream news texts and blog postings.
Children's alternative frameworks: Should they be directly‐addressed in science instruction?

A study was conducted to determine the effectiveness of in-depth, conceptually integrated instruction delivered via a videodisc program in eliminating children's alternative frameworks in science. Prior to instruction, pupils in two eighth-grade science classes, one of higher ability and one of lower ability, were interviewed to document their alternative frameworks (informal knowledge) for explaining two science phenomena. Interviews after instruction showed that students of both ability groups did not retain their alternative frameworks. This contradicts other research findings that children's alternative frameworks are extremely resistant to change and must be directly addressed during instruction for conceptual change to occur. A well-designed science curriculum that was intelligible, plausible, and fruitful, but did not directly address alternative frameworks during instruction, changed 92% of the alternative frameworks held by students to scientific understandings.
Effects of cytokines on mycobacterial phagosome maturation

One of the major mechanisms permitting intracellular pathogens to parasitize macrophages is their ability to alter maturation of the phagosome or affect its physical integrity. These processes are opposed by the host innate and adaptive immune defenses, and in many instances mononuclear phagocytes can be stimulated with appropriate cytokines to restrict the growth of the microorganisms within the phagosomal compartment. Very little is known about the effects that cytokines have on phagosome maturation. Here we have used green fluorescent protein (GFP)-labeled mycobacteria and a fixable acidotropic probe, LysoTracker Red DND-99, to monitor maturation of the mycobacterial phagosome. The macrophage compartments that stained with the LysoTracker probe were examined first. This dye was found to colocalize preferentially with the late endosomal and lysosomal markers rab7 and Lamp1, and with a fluid phase marker chased into the late endosomal compartments. In contrast, LysoTracker showed only a minor overlap with the early endosomal marker rab5. Pathogenic mycobacteria are believed to reside in nonacidified vacuoles sequestered away from late endosomal compartments as a part of their intracellular survival strategy. We examined the status of mycobacterial phagosomes in macrophages from IL-10 knockout mice, in quiescent cells, and in mononuclear phagocytes stimulated with the macrophage-activating cytokine IFN-(gamma). When macrophages were derived from the bone marrow of transgenic IL-10 mice lacking this major deactivating cytokine, colocalization of GFP-fluorescing mycobacteria with the LysoTracker staining appeared enhanced, suggestive of increased acidification of the mycobacterial phagosome relative to macrophages from normal mice. When bone marrow-derived macrophages from normal mice or a J774 murine macrophage cell line were stimulated with IFN-(gamma) and LPS, this resulted in increased colocalization of mycobacteria and LysoTracker, but no statistically significant enhancement was observed in IL-10 transgenic animals. These studies are consistent with the interpretation that proinflammatory and anti-inflammatory cytokines affect maturation of mycobacterial phagosomes. Although multiple mechanisms are likely to be at work, we propose the existence of a direct link between cytokine effects on the host cell and phagosome maturation in the macrophage.
Disposition of Etofibrate, Clofibric and Nicotinic Acid Esters, and Their Products in Dogs

Etofibrate, the ethylene glycol diester of clofibric and nicotinic acids, on intravenous infusion into dogs, has a terminal half-life of 2 min. The intermediate half-esters, the nicotinate and the clofibrate, have respective terminal half-lives of 4.6 and 1.7 min and appear fleetingly when etofibrate is administered. In contrast to the 42-h terminal half-life of clofibric acid, the other final transformation product, nicotinic acid, shows saturable or dose-dependent pharmacokinetics in dogs that conform to the Michaelis–Menten equation with a terminal half-life of 4.4 min at low concentrations (< 6.9 μM/kg). Three distinct metabolites of nicotinic acid can be identified and assayed chromatographically in the urine. The partition properties were similar to nicotinic acid. Nicotinic acid is excreted 30% unchanged into urine with a renal clearance of 70 mL/min in 27-kg dogs.
Red and Processed Meat Consumption and Risk of Incident Coronary Heart Disease, Stroke, and Diabetes Mellitus A Systematic Review and Meta-Analysis

Background— Meat consumption is inconsistently associated with development of coronary heart disease (CHD), stroke, and diabetes mellitus, limiting quantitative recommendations for consumption leve...
Desorption energies of linear and cyclic alkanes on surfaces: anomalous scaling with length

Abstract The desorption energies, Δ E des ‡ , of linear and cyclic alkanes on the Cu(1 1 1) and Pt(1 1 1) surfaces have been measured and compared to the values of the Δ E des ‡ measured on a number of other surfaces. For sets of short linear and cyclic alkanes (n-CNH2N+2 and c-CNH2N, N=3–12) desorbing from single crystalline surfaces the Δ E des ‡ scale linearly in chain length with the form Δ E des ‡ (N)= Δ E+ Δ E CH ·N . The quantity ΔECH can be equated with a segmental contribution to the Δ E des ‡ , however, the physical origin of the non-zero intercept, ΔE, is not clear. Comparison of the intercepts, for the linear and cyclic alkanes show that they are similar to one another on the Cu(1 1 1) surface and on the Pt(1 1 1) surface. This comparison rules out the possibility that ΔE arises from endgroup effects. Scaling of the Δ E des ‡ against the polarizabilities, α, of the alkanes also reveals that ΔE cannot arise from the scaling of the polarizability with chain length. We discuss other possible origins of ΔE including lattice commensurability effects, temperature, and desorption order.
LPCVD Of Silicon Carbide Films From The Organosilanes Diethylsilane And Di-T-Butylsilane

In this paper, the kinetics and properties of amorphous LPCVD silicon carbide films synthesized from the single organosilane precursors diethylsilane (DES) or di-t-butylsilane (DTBS) are discussed. For DES, the growth rate is observed to vary linearly with flow rate and pressure, while for DTBS, a square root dependency is seen as a function of these parameters. An Arrhenius type behavior was observed for both chemistries yielding activation energy values of 40 and 25 kcal/mol for DES and DTBS respectively. The elemental composition of the films became progressively richer in carbon as the deposition temperature increased with stoichiometry occurring near 750° C. The film stress was dependent on carbon content and became compressive at compositions near Si0.35C0.65. The hardness and Young’s modulus of the films increased with increasing carbon content reaching maxima near stoichiometry. Free-standing membranes produced under optimal processing conditions had a relatively low optical transmission due to excess carbon. Although, transmission characteristics were improved by adding NH3 in the reaction chamber, the resulting silicon carbonitride films exhibited undesirably high values of tensile stress.
Radar Measurement of Precipitation-Related Depolarization in Thunderstorms

Observations of thunderstorm regions above 4 km have been made by means of a two-channel polarization diversity radar at 16.5 GHz. There is a brief description of the radar equipment. Computer-generated plots of the radar data show regions of depolarization presumably originating in ice-crystal clouds, and abrupt changes in depolarization induced by lightning strokes. There is a discussion of the physical processes causing the various effects.
Changing paradigms in the immunological science of allergy: 2008

Our evolving knowledge of the universe of immune cytokines has permitted more precise definition of the extensive involvement of many cell-derived protein factors in the mediation of allergic diseases and asthma. Several newly recognized cytokines, which are derived from epithelial cells of the respiratory system, skin, and gastrointestinal tract or intraepithelial T cells in the context of interactions with nonimmune parenchymal cells, have potent stimulatory or inhibitory effects on the differentiation and/or activities of T helper (Th) 2-type CD4 T cells. Their properties and effects are reviewed from the perspective of novel targets for antiallergic therapy.
Early Conversations and Word Learning: Contributions from Child and Adult

Temporal and topic contingencies between child and mother speech are reported at 2 achievements in language development in the second year. Measured against their respective baseline rates of speech, children were most likely to talk before mother speech and mothers most likely to talk after child speech. This pattern, evident at both language achievements, increased in amplitude with development. These early conversations were generated by the children; neither their interactions nor word learning depended on adult-scaffolded formats. Only about one-third of all child speech occurred in response to something mothers said; only half of all child speech received a topic-related response. When mothers responded, they most often simply acknowledged, repeated, or clarified what the child said. The results supported the intentionality model for language development, in which the child's role is primary: Children learn words for expression and interpretation in order to share contents of mind, bringing words to their conversations that they've already learned in other contexts.
Sternal defects associated with congenital pericardial and cardiac defects

We describe three cases of sternal defects of varying severity associated with other congenital anomalies. In the most severe case, both anterior and posterior defects were seen, with near-absence of the sternum and pericardium continuous with a large omphalocele. This resulted in external location of organs usually confined within the thoracic and abdominal cavities. A ventricular septal defect was present, and the arterial duct was absent. The course of the ascending aorta was anomalous. The baby had anencephaly and rachischisis. In the intermediate case, a proximal sternal cleft was associated with shortening of the ster num, and absence of the manubrium. Anterior pericardial and diaphragmatic defects were seen, while a scalp defect and an encephalocele were present on the posterior aspect of the head. This baby had tricuspid atresia. The qremaining case had only an anterior defect with a shortened sternum. A supra-umbilical omphalocele contained a left ventricular diverticulum without interposing pericardium or diaphragm. Ventricular and atrial septal defects were present. The first two cases can be considered as representing fail ure of development of both an anterior and a posterior midline field. The third case, much milder than the other two, represents failure of development of an anterior field.
Fatigue crack propagation of multiple coplanar cracks with the coupled extended finite element/fast marching method

A numerical technique for modeling fatigue crack propagation of multiple coplanar cracks is presented. The proposed method couples the extended finite element method (X-FEM) [Int. J. Numer. Meth. Engng. 48 (11) (2000) 1549] to the fast marching method (FMM) [Level Set Methods & Fast Marching Methods: Evolving Interfaces in Computational Geometry, Fluid Mechanics, Computer Vision, and Materials Science, Cambridge University Press, Cambridge, UK, 1999]. The entire crack geometry, including one or more cracks, is represented by a single signed distance (level set) function. Merging of distinct cracks is handled naturally by the FMM with no collision detection or mesh reconstruction required. The FMM in conjunction with the Paris crack growth law is used to advance the crack front. In the X-FEM, a discontinuous function and the two-dimensional asymptotic crack-tip displacement fields are added to the finite element approximation to account for the crack using the notion of partition of unity [Comput. Meth. Appl. Mech. Engng. 139 (1996) 289]. This enables the domain to be modeled by a single fixed finite element mesh with no explicit meshing of the crack surfaces. In an earlier study [Engng. Fract. Mech. 70 (1) (2003) 29], the methodology, algorithm, and implementation for three-dimensional crack propagation of single cracks was introduced. In this paper, simulations for multiple planar cracks are presented, with crack merging and fatigue growth carried out without any user-intervention or remeshing.
New Parameterizations and Features for PSCFG-Based Machine Translation

We propose several improvements to the hierarchical phrase-based MT model of Chiang (2005) and its syntax-based extension by Zollmann and Venugopal (2006). We add a source-span variance model that, for each rule utilized in a probabilistic synchronous context-free grammar (PSCFG) derivation, gives a confidence estimate in the rule based on the number of source words spanned by the rule and its substituted child rules, with the distributions of these source span sizes estimated during training time. We further propose different methods of combining hierarchical and syntax-based PSCFG models, by merging the grammars as well as by interpolating the translation models. Finally, we compare syntax-augmented MT, which extracts rules based on targetside syntax, to a corresponding variant based on source-side syntax, and experiment with a model extension that jointly takes source and target syntax into account.
Infant feeding and women's work in Western Samoa: a hypothesis, some evidence and suggestions for future research.

This paper argues that a key reason for the decline in the age of weaning in 3rd world countries may be an increasing workload for women associated with increasing involvement in the cash economy. This hypothesis is considered in light of data collected in an anthropological field study of a rural village in Western Samoa. Methods used were a village census a household survey with fertility histories and questions on household economy a questionnaire on breastfeeding key informant interviews observations made during residence in the village and archival research. The ethnographic data suggest the possibility of a causal relationship between a decline in the age of weaning and an increasing workload for women in Western Samoa. In addition other factors thought to account for a decline in the age of weaning such as bottle feeding and urbanization are unimportant in rural Western Samoa. (authors)
Synthesizing iterative functions into delay-insensitive tree circuits

Speed, cost and correctness may be the most important factors in designing a digital system. This paper proposes a novel and general methodology to synthesize iterative functions into potentially high speed low cost and very robust circuits, called delay-insensitive combinational tree iterative circuits. In particular our methodology can be applied to synthesize binary addition and comparison into delay insensitive adders and comparators.
Wire-sizing for delay minimization and ringing control using transmission line model

In this paper, we consider continuous wire-sizing optimization for delay minimization and ringing control. The optimization is based on a fast and accurate delay estimation method under a finite ramp input, where an analytical expression is also derived to estimate overshoot/undershoot voltage. In this paper we specify the wire shape to be of the form f(x)=ae/sup -bx/, since previous studies under the Elmore delay model suggest that exponential wire shape is effective for delay minimization. The relevant transmission line equations are solved by using the Picard-Carson method. The transient response in the time domain is derived as a function of a and b. The coefficients a and b are then determined such that either the actual delay (50% delay) is minimized, or the wiring area is minimized subject to a delay bound. At the same time, the overshoot/undershoot voltage is bounded to prevent false switching. Our method for delay estimation is very efficient. In all the experiments we performed, it is far more accurate than the Elmore delay model and the estimated delay values are very close to SPICE's results. We also find that in determining the optimal shape which minimizes delay, the Elmore delay model performs as good as our method in terms of the minimum actual delay it achieves, i.e. the Elmore delay model has high fidelity. However, in determining the optimal shape which minimizes area subject to a delay bound the Elmore delay model performs much worse than our method. We also find that the constraint for overshoot/undershoot control does affect optimization results for both delay and area minimization objectives.
Mechanism of Negative Feed-back Regulation of c- myc Gene Expression in B-Cells and its Inactivation in Tumor Cells

The c-myc proto-oncogene is involved in the control of cellular proliferation and differentiation (for review see Cole 1986). Its deregulated expression, caused by chromosomal translocation (Dalla-Favera 1982, 1983; Taub 1982), amplification (Collins and Groudine 1982; Dalla-Favera 1982) or retroviral insertion (Hayward 1981), is associated with lymphoid and non-lymphoid malignancies in different species. The mechanism regulating normal c-myc gene expression and the cause of its deregulation in tumor cells remains largely unknown. Since normal c-myc alleles are down-regulated in the presence of constitutively expressed c-myc oncogenes in naturally occurring tumors (Leder 1983) as well as in in vitro transformed cells (Rapp 1985; Lombardi 1987) and transgenic mice (Adams 1985), it has been frequently suggested that c-myc expression may be under the control of negative feed-back regulation. However, the actual existence of such a regulatory function remains controversial and its mechanism of action unknown. In an attempt to clarify these issues we have characterized a negative feed-back loop regulating c-myc expression in human EBV-immortalized lymphoblastoid cells and then comprehensively investigated the activity of this mechanism in a number of cell types. Our results provide direct evidence for the existence of a dose-dependent negative feed-back loop and preliminarily define its mechanism. However, we find that this mechanism is inactive in all tumor cell lines tested derived from a variety tissues, suggesting that its inactivation may represent a general regulatory disturbance of transformed cells.
Bittor approach to the representation and propagation of uncertainty in measurements

In this paper, the authors propose a new method for the propagation of uncertainty through non linear algorithms that may contain conditional statements. The approach is based on bittors, that are bit vectors where bits are expressed in terms of their probability to take value 1 or 0. Provided the logic operations between bittors are defined, the system of bittor numbers is introduced together with the fundamental operations. The bittor numbers can be processed with any algorithm provided the fundamental operations are redefined for bittors. This approach is suitable for multithread algorithms, thus conditional statements, can be handled easily. The implementation of bittor numbers and their operations in the Matlab environment is presented together with the numerical results of an example of application. The entropy as a measure of the information content of the bittor number is defined and proposed as a metric of loss of information content due to the elaboration. The authors discuss strengths, weaknesses and challenges of the approach and provide an overview of the potential benefits of this method.
Absorption and Scattering in Plane Parallel Turbid Media

The Kubelka–Munk hyperbolic equations for reflectance and transmittance of a turbid, isotropically scattering medium have been found formally identical with the solution for reflected and transmitted fluxes of Chandrasekhar’s radiative-transfer equation for isotropically highly scattering media. The absorption and scattering coefficients of the two theories have been related through numerical coefficients. The Kubelka–Munk absorption coefficient is nearly proportional to the true absorption coefficient in the range of reflectance values between 0.6 and 1 but deviations from proportionality up to a factor of 2 occur for lower reflectance values.
Aimed Electrocardiography with Simple Bipolar Leads Experimental Study of a New Concept: Surface Search for Unweighted Leads Which Record the ECG from Limited Cardiac Areas

All currently employed ECG and VCG leads vectorially record added contributions from all cardiac regions. Aimed leads, if feasible, would yield information cancelled during addition. Three artificial dipoles (µ1, µ2, µ3) are placed within a torso model in the approximate right ventricular free wall, posterobasal wall of left ventricle, and inferior cardiac surface, respectively. Dipoles are excited in turn and torso surface potential fields are mapped for each dipole. A bipolar lead connecting any pair of points on the same equipotential of the field produced by µ1 does not show a deflection when µ1 is excited, but responds to µ2 and µ3. If this lead is now so placed that its two electrodes, while remaining on the µ1 equipotential, are on the same equipotential of the µ2 field as well, then it will respond to µ3alone; it is aimed at the latter. Superimposing the three field maps and searching for those equipotential lines of one map which cross the same equipotential line of another map twice, provides a ...
Spinal Tumors and Radiosurgery

Spinal tumors epitomize a challenging radiation-treatment paradigm due to the anatomic nature and proximity of the spinal cord. The spine comprises a chain of functional units, with serial-organ-like behavior. Late spinal cord injury or progressive myelopathy may manifest as paresthesias, hyperreflexia, and complete paresis below the irradiated spinal cord segment. Image-guided technology coupled with highly conformal treatment-planning techniques has allowed the safe delivery of tumor-ablative doses of radiotherapy for patients with benign tumors, primary malignant tumors, and spinal metastases. Spinal metastases are more prevalent and radiosurgery results in very high rates of local control for radioresistant metastases. Radiosurgery has been utilized for metastases in the setting of no prior treatment, but also in patients who have recurred after conventional palliative spine radiotherapy and in patients who have required surgical intervention and require postoperative radiation. Higher radiation doses provide better, more durable tumor control, even with hypofractionated regimens. Radiosurgical techniques limit the dose and the volume of normal tissues that are irradiated and treatment is well tolerated. Hence, the rate of severe complications with high-dose hypofractionated spine radiosurgery is extremely low, even when used as salvage therapy in previously irradiated tissue. In complex cases where tumor is located at the dural margin, novel techniques including high-dose intraoperative brachytherapy (i.e., 32P) in conjunction with image-guided radiation therapy offers a significant benefit.
Paraneoplastic vitelliform retinopathy in a patient with treated choroidal melanoma.

Purpose To describe a peculiar case of paraneoplastic vitelliform maculopathy/retinopathy in a patient with treated choroidal melanoma. Methods A case report of a 58-year-old woman with a history of treated choroidal melanoma 16 years before developing visual changes in the setting of metastatic choroidal melanoma. Results We demonstrate bilateral, multifocal vitelliform subretinal lesions and focal, neurosensory retinal detachment associated with metastatic melanoma. Conclusion Paraneoplastic vitelliform maculopathy/retinopathy should be considered in patients with or without a history of melanoma, who have unexplained serous, vitelliform retinal detachments, especially with atypical or absence of leakage on fluorescein angiography.