cssi/SciSciGPT-SciSciNet huggingface dataset:
Requirement of phenylalanine 343 for the preferential delta 4-lyase versus delta 5-lyase activity of rat CYP17.

Abstract Site-directed mutagenesis of a domain (amino acids 343-348) within the conserved region of rat CYP17 was performed to investigate species-specific differences between rat and human/bovine delta 4-versus delta 5-lyase activity. This domain displays substantial deviations between the rat and human/bovine/pig sequences and includes Arg346, which is known to be essential for delta 4-lyase (Kitamura, M., Buczko, E., and Dufau, M. L. (1991) Mol. Endocrinol. 5, 1373-1380) and delta 5-lyase activities. Analysis of the delta 4-lyase activity of mutant rat CYP17 cDNA expressed in nonsteroidogenic COS-1 cells revealed that substitution of Phe at position 343 in the rat with Ile of the human/bovine sequence resulted in a reduction in delta 4-lyase activity to levels in the range of the delta 5-supported reaction. This Phe343-->Ile mutant CYP17 did not exhibit changes either in delta 5-supported lyase activity or in delta 4- and delta 5-hydroxylase activities. Substitution of Asn344, Ser347, and His348 in rat CYP17 with the corresponding bovine amino acids Ser, Asn, and Arg did not enhance this effect. Thus, the reduced activity of the bovine CYP17 delta 4-lyase reaction can be mimicked in part in the rat polypeptide by the substitution of Phe343 with the bovine counterpart, Ile. Unlike the bovine CYP17-catalyzed reaction, the rat Phe343-->Ile mutant exhibited a low level lyase activity (kcat) that did not discriminate between delta 4- and delta 5-substrates. These results suggest that the presence of Phe343 enhances the delta 4-supported lyase activity possibly through stabilization of a delta 4-specific interaction.
Application of system identification to high performance aircraft

A concept of system identification applied to high performance aircraft is introduced followed by a discussion of the identification methodology. This methodology includes five steps: model postulation, design of an experiment, data compatibility analysis, model structure determination and parameter estimation combined with data collinearity diagnostic, and model validation. Special emphasis is given to optimal input design, model structure determination, data collinearity detection and assessment, and biased estimation techniques suitable for the analysis of highly collinear data. These parts of the methodology are demonstrated in examples. The paper is completed by notes on possible future developments and concluding remarks. >
The logic of occurrence

A general problem in qualitative physics is determining the consequences of assumptions about the behavior of a system. If the space of behaviors is represented by an envisionment, many such consequences can be represented by pruning states from the envisionment. This paper provides a formal logic of occurrence which justifies the algorithms involved and provides a language for relating specific histories to envision ments The concepts and axioms are general enough to be applicable to any system of qualitative physics. We further propose the concept of transverse quantities as a general solution to qualitative versions of Zeno's paradox. The utility of these ideas is illustrated by a rational reconstruction of the pruning algorithms used in FROB, a working AI program.
Physical design and implementation of POWER8™ (P8) server class processor

POWER8™ (P8) processor is a 12-core, 649mm2, 4.2B transistor chip fabricated in IBM's 22nm SOI technology with 2.5× socket performance improvement over its 32nm predecessor, POWER7+, driven by big data application and power efficient computing. Highly distributed chip voltage regulator achieves a peak power efficiency of 90.5%. Resonant clock design is used in 13 clock meshes to achieve about 4% power savings for the chip. This chip is built with three thin-oxide transistor Vt for power/performance benefit and one thick-oxide transistor to enable high-voltage circuits. In order to achieve desired performance within the power envelop, P8 is built with 7 input voltages and 15-layers of metals along with the use of pulsed-clock latches. The P8 has 15823 total pads: 5982 power, 7742 ground and 2099 signal. The power/performance complexity, size of the die, along with high operating frequency presented significant challenges to complete the design on an aggressive schedule. Some of the design methodology and implementation innovations in P8 have been presented in this paper, with an emphasis on macro design topologies (custom, array and synthesis), timing methodology, as well as the electrical characterizations performed in the chip bring-up lab.
Dynamic Radiation Belt Modeling at the Air Force Research Laboratory

Despite its well-known limitations, diffusion remains an important concept for modeling radiation belt energization and transport. Recent work at AFRL has applied radial diffusion to observations of: (a) 1 - 10 MeV equatorially mirroring protons at 1.2 2 MeV electrons at geosynchronous orbit associated with high speed solar wind streams. In general, encouraging results were obtained, but only after implementing: (1) non-steady state initial conditions; (2) time-dependent boundary conditions; (3) realistic magnetic field models; (4) tweaked, scaled, fit, activity-dependent, or enhanced diffusion coefficients. This paper reviews these various modeling efforts, including the modifications that they required, their successes and failures, and lessons learned.
Monostatic through-wall detection of a metallic sphere

The paper introduces a time-domain technique and a homomorphic (cepstrum-domain) technique for detecting a metallic sphere placed behind a lossy dielectric wall. Both of them rely on the monostatic analysis of the scattered electromagnetic waves from an electromagnetic impulse incident on the wall. The performance of the two approaches are compared at various distances from the wall.
Pharmacokinetics of once and twice daily dosing of intravenous tobramycin in paediatric patients with cystic fibrosis

The optimal dosing of intravenous tobramycin for treatment of pulmonary exacerbations in paediatric cystic fibrosis (CF) patients has not been completely delineated. We performed a retrospective study evaluating the pharmacokinetics and pharmacodynamics of once daily dosing (ODD) of IV tobramycin compared to twice daily dosing (TDD). Fifty-nine and 44 patients were included in the ODD and TDD groups, respectively. Once daily dosing achieved higher Cmax as compared to TDD (29.5 ± 11.0 vs 19.0 ± 4.9, P 1.0 mg/l. Twice daily dosing may be a viable alternative to ODD in treating organisms with MICs ≤ 1.0 mg/l; however, with MICs >1.0 mg/l, ODD is likely necessary to achieve goal Cmax:MIC ratios.
Transdiagnostic dimensions of anxiety and depression moderate motivation-related brain networks during goal maintenance.

Background: Advancing research on the etiology, prevention, and treatment of psychopathology requires the field to move beyond modular conceptualizations of neural dysfunction toward understanding disturbance in key brain networks. Although some studies of anxiety and depression have begun doing so, they typically suffer from several drawbacks, including: (1) a categorical approach ignoring transdiagnostic processes, (2) failure to account for substantial anxiety and depression comorbidity, (3) examination of networks at rest, which overlooks disruption manifesting only when networks are challenged. Accordingly, the present study examined relationships between transdiagnostic dimensions of anxiety/depression and patterns of functional connectivity while goal maintenance was challenged. Methods: Participants (n = 179, unselected community members and undergraduates selected to be high/low on anxiety/depression) performed a task in which goal maintenance was challenged (color-word Stroop) while fMRI data were collected. Analyses examined moderation by anxiety/depression of condition-dependent coupling between regions of dorsolateral prefrontal cortex (dlPFC) previously associated with approach and avoidance motivation and amygdala/orbitofrontal cortex (OFC). Results: Anxious arousal was positively associated with amygdala↔right dlPFC coupling. Depression was positively associated with OFC↔right dlPFC coupling and negatively associated with OFC↔left dlPFC coupling. Conclusions: Findings advance the field toward an integrative model of the neural instantiation of anxiety/depression by identifying specific, distinct dysfunctions associated with anxiety and depression in networks important for maintaining approach and avoidance goals. Specifically, findings shed light on potential neural mechanisms involved in attentional biases in anxiety and valuation biases in depression and underscore the importance of examining transdiagnostic dimensions of anxiety/ depression while networks are challenged. Depression and Anxiety 31:805–813, 2014. C � 2014 Wiley Periodicals, Inc.
Arabic Literary Salons in the Islamic Middle Ages: Poetry, Public Performance, and the Presentation of the Past

Reviewed Medium: book Authors: Samer M. Ali Year: 2010 Pages: 312 Publisher: University of Notre Dame Press ISBN: 978-0-268-02032-3 (soft cover).
Effect of streptolysin S on liposomes Influence of membrane lipid composition on toxin action

Abstract The effect of the bacterial cytolytic toxin, streptolysin S, on liposomes composed of various phospholipids was investigated. Large unilamellar vesicles containing [14C]sucrose were prepared by reverse-phase evaporation, and membrane damage produced by the toxin was measured by following the release of labeled marker. The net charge of the liposomes had little or no effect on their susceptibility to steptolysin S and the toxin was about equally effective on liposomes composed of phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidylglycerol. Experiments with liposomes composed of synthetic phospholipids showed that the ability of the toxin to produce membrane damage depended on the degree of unsaturation of the fatty acyl chains. The order of sensitivity was C18 : 2 phosphatidylcholine > C18 : 1 phosphatidylcholine > C18 : 0 phosphatidylcholine = C16 : 0 phosphatidylcholine. Liposomes containing the latter two phospholipids were virtually unaffected by streptolysin S, and experiments with C18 : 0 phosphatidylcholine suggested that toxin activity does not bind to liposomes composed of phospholipids with saturated fatty acyl chains. The inclusion of 40 mol% cholesterol in C16 : 0 phosphatidylcholine and C18 : 0 phosphatidylcholine liposomes made these vesicles sensitive to streptolysin S. Egg phosphatidylcholine liposomes, which were unaffected at 0°C and 4°C became susceptible to the toxin at these temperatures when cholesterol was included. Liposomes composed of C14 : 0 phosphatidylcholine were unaffected by streptolysin S at temperatures below the chain-melting transition temperature (23°C) of this phospholipid, but became increasingly susceptible above this temperature. The results suggest that the fluidity of the phospholipid hydrocarbon chains in the membrane is important in streptolysin S action.
FEEDBACK INHIBITION OF THYMIDINE KINASE BY THYMIDINE TRIPHOSPHATE.

THE search for rate-controlling enzyme systems in the overall synthesis of DNA has led a number of investigators to study the reactions in the sequence from Tdr to dTTP. Little duplication of effort has occurred despite the similarity in overall objectives. The work reported by Dr Smellie difiers from our work in terms of source of enzyme, reaction components, separation of products, method of quantitating the data, and problems emphasized [a]. Dr Smellie utilized extracts from the Landschutz ascites tumor cells while our work was done with extracts from the NlSl strain of cells grown in tissue culture in vigorously shaken suspensions in a modified Eagle medium. This strain was derived from Novikoff hepatoma cells and in addition to being the richest source of Tdr kinase and TMP kinase found, it is also notably lacking in side reactions that utilize Tdr. In the following scheme
The differentiable structure of three remarkable diffeomorphism groups

The goal of this paper is to find the "Lie groups" for three well-known Lie algebras: the globally Hamiltonian vector fields, the infinitesimal quantomorphisms and the homogeneous real-valued functions of degree one on the cotangent bundle minus the zero section. In all our considerations the underlying manifold is assumed to be compact without boundary. Before explaining and motivating our results, a very brief review of the "Lie group" structure of diffeomorphism groups is in order ([9, 10, 18]). If M, N are compact, boundaryless, finite-dimensional manifolds, rN: TN--,N, the tangent bundle of N, an HS-map, s>(dimM)/2, from M to N has by definition all derivatives of order (dim M)/2. Then the space IP(M, N) of all such maps is a Hilbert manifold whose tangent space at every point is the Hilbert space T I. H~(M, N) = {gelid(M, TN) I ~:N ~ g =f} If E---, M is a vector bundle, the same construction works for all HS-sections HS(E) of E, s > (dim M)/2. If N = IR, HS(M, N) will be denoted by C~(M, IR). Let ~ + I ( M ) denote the diffeomorphisms of M of Sobolev class H s+l, i.e. r t ~ + l ( M ) if and only if t/ is bijective and t/, t ] l : M---,M are of class H ~+1. ~s+l(M) is a topological group, and since it is open in Hs+I(M,M), it is also a Hilbert manifold. Right multiplication R~: @~+ ~(M) ~ + I(M), R,(~) = ~ o t/ is C ~ for each t / ~ Y +~(M) and if t/E@ s+k+l(M), left multiplication L , : ~ + t ( M ) ~ + I ( M ) , L~(~)=t/o~ is C k. The inversion map t/~--~t/-1 in ~ + t(M) is only continuous. The tangent maps of R, and L, at e, the identity of ~ + a ( M ) , are given by Tr TeL,(X)=T~oX, where X~Yys+I(M) =HS+I(TM), the set of all H~+l-vector fields on M. The tangent space at e, Tr coincides with Y'~+~(M), which is a Sobolev space. The bracket [X, Y] of X, y ~ f s + I(M ) is however only of class H ~ (one derivative is lost). The usual bracket of vector fields is the Lie algebra bracket of 5F ~+ X(M), i.e. if J(,
Zoster-associated mononeuropathies (ZAMs): a retrospective series.

Introduction: Zoster-associated limb paresis is an uncommon complication of herpes zoster (HZ) and one whose precise pathophysiologic mechanism is poorly understood. Occasionally, the paresis results from a zoster-associated mononeuropathy (ZAM). Methods: Mayo Clinic records between 1996 and 2010 were reviewed for patients with ZAM whose clinical, electrophysiologic, and radiographic features were then abstracted. Results: Ulnar (2), median (3), femoral (1), and sciatic (2) mononeuropathies were identified. Most patients had moderate to severe weakness in affected muscles, and most had post-herpetic neuralgia (88% at 1 month and 71% at 4 months). The minimum duration of weakness was prolonged (mean, 281.9 days; range, 45–1242 days). Nerve magnetic resonance imaging (MRI) was abnormal, demonstrating nerve enlargement (4/4 cases), T2 signal hypertintensity (2/4 cases), or enhancement (1/4 cases). Conclusions: While ZAM is an uncommon occurrence following cutaneous HZ, it is associated with significant weakness, high rates of post-herpetic neuralgia, and prolonged morbidity. Muscle Nerve, 2012
Welcome to Processes—A New Open Access Journal on Chemical and Biological Process Technology

As the result of remarkable technological progress, this past decade has witnessed considerable advances in our ability to manipulate natural and engineered systems, particularly at the molecular level. These advancements offer the potential to revolutionize our world through the development of novel soft and hard materials and the construction of new cellular platforms for chemical and pharmaceutical synthesis. For these technologies to truly impact society, the development of process technology that will enable effective large-scale production is essential. Improved processes are also needed for more established technologies in chemical and biochemical manufacturing, as these industries face ever increasing competitive pressure that mandates continuous improvement. [...]
Evolution of ZnS Nanostructure Morphology under Interfacial Free-Energy Control

Under hydrothermal conditions and extremely high NaOH activity, ZnS forms nanostructures with complex morphologies that are based upon individual or interpenetrating nanosheets. Nanostructure morphology is independent of the size of the ZnS precursor (3 nm, 20 nm, or bulk) but varies systematically with NaOH concentration, producing compact microspheres, open nest- and flowerlike structures, and finally, individual nanosheets. The observations are consistent with a concept of nanostructure morphology controlled by a single parameter-the interfacial free energy of the ZnS (001) face. The synthesis of thermodynamically stable nanostructures open opportunities for new synthetic routes of materials with complex architectures.
Bose System of Hard Spheres

A generalized pseudopotential for hard-sphere interaction is obtained, which is valid for all angular-momentum states. This pseudopotential is then used in the evaluation of both the ground-state energy and the excitation spectrum for a dilute Bose system of hard spheres. The calculated ground-state energy agrees with that obtained by other authors; the excitation spectrum obtained for liquid helium resembles the phonon-roton spectrum introduced by Landau.
The reliability of self-recorded behaviors

The purpose of this paper is to make explicit some of the problems involved in assessing the reliability of self-recorded measures of behavior. An examination of investigations in the area of self-regulation of behavior revealed instances in which there either had been no assessment of the reliability of the self-recordings or else such procedures were not made explicit. In the absence of reliability estimates it is difficult to evaluate the reported successes of behavior-therapy techniques that make use of self-control procedures. At the very least, reliability estimates in terms of interobserver agreement should be reported. The current procedures for recording self-behavior and their relationship to the problems of reliability assessment are discussed.
Detection of clinical and subclinical retinal abnormalities in neurosarcoidosis with optical coherence tomography

The aim of this work was to determine if neurosarcoidosis (NS) patients exhibit quantitative and/or qualitative in vivo evidence of retinal abnormalities on optical coherence tomography (OCT). Retinal imaging was performed using spectral-domain Cirrus HD-OCT in 20 NS patients (40 eyes) and 24 age-matched healthy controls (48 eyes). Study participants also underwent magnetic resonance imaging of the brain and spine, cerebrospinal fluid (CSF) analysis, and detailed neurological and ophthalmological evaluation. Quantitative OCT abnormalities of average macular thickness (AMT), peri-papillary retinal nerve fiber layer (RNFL) thickness, or both, were detectable in 60% of NS patients. Of NS patients with ocular symptomatology, 75% demonstrated quantitative OCT abnormalities, while only 25% had detectable abnormalities on detailed ophthalmological assessment. Furthermore, 33% of NS patients without ocular symptoms had quantitative OCT changes, while only 8% had abnormal ophthalmologic examination. RNFL and macular thinning and swelling were significant in the NS cohort compared to healthy controls (variance ratio testing; RNFL: p = 0.02, AMT: p = 0.006). AMT also correlated inversely with disease duration (r s = −0.65, p = 0.002). Patient proportions with OCT abnormalities did not differ according to NS subtype (myelopathic, meningeal, or encephalitic NS), CSF findings, or immunotherapy exposure. No qualitative OCT abnormalities were detected. Retinal abnormalities occur in all NS subtypes, and may be clinical or subclinical. Our findings suggest OCT may enable greater detection of retinal abnormalities in NS than ophthalmological assessment alone, and have implications for the assessment of ocular involvement in NS, and sarcoidosis in general. Longitudinal NS studies utilizing OCT are warranted.
Hemophilic arthropathy: Effect of home care on treatment patterns and joint disease

To evaluate the efficacy of home care therapy on hemophilic arthropathy, data were analyzed in 19 patients with hemophilia who had been on home therapy for more than four years. Usage of replacement material, number of bleeding episodes, and clinical and radiographic assessment of joint status were evaluated. Patients were divided into three treatment groups (prophylaxis, combination, and episodic care) for further comparison. In all treatment groups, a significant decrease in product usage occurred with age ( P P
Ross' first homograft replacement of the aortic valve

Ross' first homograft replacement of the aortic valve was reported in 1962. The homograft has been in continuous use around the world ever since. Much has been learned about how to handle homografts, both before and during their implantation. Homografts have special advantages, which make them an appropriate choice in a number of settings. This first successful case by Donald Ross set the stage for the growth in homograft valve use and the subsequent development of many ways of using allograft cardiovascular tissue for optimal cardiac reconstructions.
More to Mutton than Meets the Eye

A 64-year-old Mexican fisherman with a history of syphilis is diagnosed with panuveitis of the right eye after presenting with unilateral blurry vision, redness, and pain. A PPD was 35X30mm, and chest X-ray suggested tuberculosis. The patient’s pain and vision improved with 4-drug anti-tuberculous therapy, topical steroids, and cycloplegic eye drops.
Early Contributions of Medical Students, Interns, and Residents to the Development of Radiology

Among all that has and will be written of the history sumrounding the discovery of the X-ray, I would add a word about the roles played by medical students, interns, and residents in the development of the science we now call radiology. The group consists of those who became infatuated with the ray while in medical school, those who abandoned various other professions to tread the path of the X-light, and those who used their sharp intellect to advance the science. Despite the demands of their medical studies and duties, they all found time to explore the new field of radiology. Foremost in this group was Walter Bradford Cannon
Testicular metamorphosis rates in European starlings maintained under short daily photophases.

Juvenile male European Starlings(Sturnus vulgaris) were maintained under discrete fixed daily photophases ranging from 1 to 11 h in duration. Treatment began on 20 December when all birds were reproductively quiescent, and continued until 14 June of the following year.In situ measurements of left testis widths at monthly intervals documented testicular width increases to levels associated with complete spermatogenesis in birds under all photoperiod regimens. Starlings maintained under the shortest and longest photoperiods required fewer days of treatment to achieve spermatogenic testes than did those under intermediate-length photoperiods. Data are consistent with the hypothesis that prolonged daily periods of darkness result in oscillations of a circadian timing system stimulating increased gonadotropin secretion and consequent testicular metamorphosis.
A Human Factors-Based Assessment Framework for Evaluating Performance in Control Room Interface Design

OCCUPATIONAL APPLICATIONS Evaluating the effects of control room interface design on operator performance is crucial to maintaining productivity and safety. Current regulations in the petrochemical industry encourage the inclusion of human factors principles in designing displays and the environment but provide little guidance on evaluation. The framework presented in this article can be used to evaluate petrochemical control room interface designs under a variety of conditions, including workload and experience levels. Applications of this framework include the evaluation of novel interface designs to determine which alternatives result in the highest performance and reasonable perceived workload levels. This framework could also be used to evaluate the effects of other performance-shaping factors, such as fatigue.TECHNICAL ABSTRACT Background: The petrochemical industry has a need to improve the design of control room interfaces, but regulations on how to evaluate designs are sparse. Purpose: This study...
Nutria Grazing Preference as a Function of Fertilization

In Louisiana, subsiding wetlands frequently receive diverted fresh river water, which contains nutrients, stimulates vegetative growth, and may increase vertical accretion via vegetative growth. When river water is introduced, varying nutrient and salinity concentrations are produced. These varying conditions within marshes probably influence the feeding habits of herbivorous animals because of a preference for vegetation high in nutrients and low in salinity. Nutria (Myocastor coypus), a large introduced rodent, can negatively affect wetlands. We speculate that, driven by a biological need for nitrogen, nutria may affect treated wetlands more than untreated wetlands. Therefore, we sought to determine if wild-captured nutria preferred fertilized versus unfertilized plants of the following species: Panicum hemitomon Schult., Sagittaria lancifolia L., and Spartina patens (Aiton) Muhl. Nutria showed a significant preference for fertilized over non-fertilized samples, potentially caused by nutrient-driven increases in the nitrogen concentrations of fertilized plants, changes in the carbon to nitrogen ratio within plant tissue, and the universal animal need for biologically available nutrients to maintain homeostasis. Preliminary findings may partially explain observations of reduced plant abundance where elevated levels of nutrients are introduced to nutrient-limited wetlands, possibly necessitating a re-examination of proposed diversion implications and focusing nutria control efforts in such places.
Application of kinetic inductance thermometers to x-ray calorimetry

ABSTRACTA kinetic inductance thermometer is applied to x-ray calorimetry, and its operation over a wide range of fre-quencies and geometries is discussed. Three amplifier configurations are described, one using a superconducting quantum int.erference device (SQUID) amplifier, another incorporating an FET amplifier in an amplitude modulated system, and the third, using a tunnel diode frequency modulated oscillator circuit. The predicted performance of each configuration is presented. 1. INTRODUCTIONWe are interested in fabricating bmad band x-ray detectors operating between 0.1 and 10 keY with thehighest achievable energy resolution. In principle, x-ray microcalorimeters operating at cryogenic temperaturesshould be able to cover this energy band with a 1 eV resolution.1'2 To date, 12 eV has been achieved using resis-tive sensors thermally connected to an x-ray absorbing material.3 In these devices, the resistive Johnson noise ofthe sensor is always present and is a limitation to the overall performance. To further improve the resolution of thedevice, the Johnson noise must be reduced. If the Johnson and amplifier noise can be reduced, the temperaturefluctuation noise will dominate the noise spectrum over a much larger range in frequencies. Experiments arecurrently being carried out with calorimeters using dielectric sensors.4 In principle, dielectric calorimeters are freeof Johnson noise, and produce signal strengths far above the remaining amplifier noise. Another way to circumventJohnson noise is through the use of superconducting materials. Below the critical temperature, only the residualresistance from superconducting surfaces need to be considered, and they prove to be negligible.5 As suggested byMcDonald,6 the temperature dependence of the kinetic inductance in a superconducting thin film can be utilized as
DEOXYRIBONUCLEIC ACID SYNTHESIS AND MITOSIS IN DIFFERENTIATED CARDIAC MUSCLE CELLS OF CHICK EMBRYOS

INTRODUCTION thymidine3H do not bind fluorescein-labeled antibody to myosin. All of the studies which form the basis of these generalizations about myofibril differentiation (1-7) have been done with skeletal muscle . Yet, it is difficult here to separate cell fusion, ending of DNA synthesis, and initiation of myosin synthesis because the three processes occur concurrently. In cardiac muscle, however, the differentiating cells do not fuse. Thus, by studying cardiac muscle, we thought that we could judge whether an obligatory relationship exists between cessation of DNA synthesis and onset of myosin synthesis, or whether it is cell fusion in skeletal muscle that turns off DNA synthesis . Shafiq et al., in an electron microscope study of skeletal muscle and cardiac muscle from 3-wk old rats, reported that no mitotic figures were found in either the skeletal muscle fibers or in myocardial cells containing myofibrils (8) . Manasek, however, in the same year, reported mitotic figures in electron micrographs of chick cardiac muscle cells that already contained myofibrils (9) . Using cinematography, Mark and Strasser (10) noted Within the past decade, numerous investigators have contended that neither DNA synthesis nor mitosis can occur in cells which have synthesized specialized or so-called "luxury" proteins (1-8) . In particular, the idea has been widely promulgated that once a muscle cell has synthesized myofilaments, it is no longer capable of replicating its DNA or undergoing mitosis. Stockdale and Holtzer, for example, working on 10 day old chick embryonic thigh muscle in vitro and 3-4-day old chick somites in vivo, concluded that myoblasts which are synthesizing contractile proteins do not synthesize DNA and do not divide (1) . Okazaki and Holtzer (2, 3) stated that nuclei regulating the synthesis of myosin cannot replicate DNA. Radioautographic studies indicated that the decision to translate for myosin and to withdraw from the cell cycle was acted on in the same GI in a myoblast that synthesized DNA for the last time about 8 hr previously (4-6) . Coleman and Coleman (7) also observed that presumptive skeletal muscle cells which incorporate
The Practical Analysis of High-Purity Chemicals. VI. Emission Spectrographic Analysis of High-Purity Acids

The spectrographic analysis of volatile acids in a high-purity form is reviewed and a procedure presented that involves evaporation of a 100-g sample under temperature controlled contamination-free conditions and emission spectrography using dc-arc excitation under controlled atmosphere. In the evaporation, graphite (10 mg) is added as a collector, sulfuric acid to convert to less volatile sulfates (with acetic, hydrochloric, and nitric acids), and also mannitol to retain boron (with hydrochloric and hydrofluoric acids). Indium is added as a internal standard. Spectra are examined for 33 elements against a multielement standard in graphite containing indium as an internal standard. For the concurrent analysis of three samples, the elapsed time is 4–10 h and the actual working time 3–5 h. Recovery studies are reported as well as the use of the procedure in the assessment of the leaching of borosilicate glass by concentrated mineral acids.
Estimating phytoplankton biomass in coastal waters of Alaska using airborne remote sensing

Abstract Empirical airborne remote-sensing relationships were examined to estimate chlorophyll a concentration in the first optical depth (chl FOD ) of coastal waters of Afgonak/Kodiak Islands during July–August 2002. Band-ratio and spectral-curvature models were tested using satellite remote-sensing reflectance ( R rs ( λ )) measurements. Additional shipboard and airborne R rs ( λ ) data were also analysed to evaluate consistency of proposed chl FOD – R rs ( λ ) relationships. Validation of chlorophyll algorithms was performed using data collected in the northern-part of the Gulf of Alaska and Bering Sea during 1996, 2002, and 2003 cruises. Likewise, oceanographic conditions during the surveys were typified to interpret variability of chl FOD fields. The SeaWiFS band-ratio algorithm OC2d was the most sensitive R rs combination ( R rs (509)/ R rs (553)) to detect chl FOD variability. Conversely, OC2a ( R rs (412)/ R rs (553)) had the lowest performance to derive chl FOD values. No valid statistical regressions were established for spectral–curvature relationships in the blue spectrum ( 5 mg m − 3 ) were preferentially located over shallow banks (∼50 m) and at the entrance of the bays. The approach used in this study to derive chl FOD values could be universal for Alaskan coastal waters. However, chl FOD – R rs ( λ ) relationships must be calibrated locally for a given season.
Human body modelling and tracking using volumetric representation: Selected recent studies and possibilities for extensions

Articulated human body modeling and tracking from vision data is an attractive research area with many potential applications. There has been a tremendous amount of related research works in this area. Therefore, having a comprehensive insight into high quality existing works and awareness of the research frontier in the area is essential for follow-up research studies. With that objective, this paper provides a review of the subarea of model based methods for human body modeling and tracking using volumetric (voxel) data. We will focus on analyzing and comparing some recent techniques, especially which are in the past two years, in order to highlight trends in the domain as well as to point out limitations of the current state of the art. Based on this analysis, we will discuss our idea of combining Laplacian Eigenspace (LE) based voxel segmentation [20] and Kinematically Constrained Gaussian mixture model (KC-GMM) method [3] to have a more powerful human body pose estimation system as well as discuss other possibilities for future work.
Social Dispersion and Genetic Variation in Two Species of Emballonurid Bats

and Summary Saccopteryx leptura and S. bilineata are closely related, sympacric species of neotropical bats that exhibit marked differences in social organization and dispersion patterns. S. leptura is monogamous and roosts in small groups of 1 to 5 (Y = 2.6) individuals that are finely dispersed. S. bilineata is harem-polygamous and roosts in larger groups of 1 to 42 (Y = 8.1) individuals that are more coarsely dispersed. Allozyme genetic studies of individuals from Trinidad, W I. demonstrate that both species carry similar, high levels of polymorphism and heterozygosity. Although significant genetic heterogeneity was observed among geographical populations of S. leptura, there is no evidence for either species that social structuring leads to inbreeding and the loss of heterozygosity, or that it promotes the development of genetic heterogeneity among social units that could accelerate the evolutionary diversification of these taxa. These results do not support a recently proposed hypothesis that social structuring in mammals has these effects. Observed intercolony genetic heterogeneity among adult males resident in multimale groups of S. bilineata is greater than intercolony heterogeneity of adult females. This is an apparent result of female dispersal and the recruitment of males into their parental groups. These results suggest that the adult males within large colonies may be kin-related.
Stereoselective Formation of a Functionalized Dipeptide Isostere by Zinc Carbenoid-mediated Chain Extension

The application of a zinc carbenoid-mediated chain extension reaction to a functionalized peptide isostere is reported. The cleavage site of human CVM protease was utilized as a target for testing the synthetic methodology. The utility of this chain extension reaction is demonstrated in the preparation of an amino acid-derived α-unsubstituted γ-keto ester, which is incorporated into a framework that mimics a tetrapeptide. The identification of a suitable protecting group strategy facilitated the application of a tandem reaction for the incorporation of an α-side chain, and the use of an oxazolidinone auxiliary provided excellent diastereocontrol in a tandem chain extension-aldol reaction. Stereoselectivity of the tandem chain extension-aldol reaction was determined through application of a CAN-mediated oxidative cleavage reaction.
Onset of Neoglaciation in the Southern Hemisphere

A review of evidence documenting an early Neoglacial (mid-Holocene) advance of mountain glaciers in South America and New Zealand reveals that of 16 glaciers for which radiocarbon age control exists, only two have associated dates that may approximate the culmination of an advance. Advances of the remaining glaciers are controlled only by minimum or maximum limiting ages. Additional dates for several New Zealand glaciers are based on weathering-rind measurements having large potential errors. Twelve of the glaciers now terminate or have terminated in lakes or in tidewater and are subject to instabilities associated with calving termini. An extensive debris cover in the ablation zone of nearly half of the glaciers makes their moraine succession potentially suspect as a record of detailed climatic variation. The two glaciers with seemingly reliable age control are located in valleys where large rock avalanches could affect glacier mass balance and lead to random advances, or where rock avalanche deposits might easily be mistaken for moraines and tills. The early Neoglacial interval has been defined primarily based on this set of data. The ages, taken at face value, suggest that the early Neoglacial advance culminated between ca. 5400 and 4900 cal yr ago (ca. 4600–4400 14C yr BP). This chronology, however, should remain provisional until improved age control is obtained for a large population of glaciers based on closely bracketing radiocarbon dates and/or an adequate number of cosmogenic isotope ages. Data from calving glaciers and those subject to rock-avalanche activity should be avoided or assessed critically. Copyright © 2000 John Wiley & Sons, Ltd.
Transcriptional profiling of the spleen in progressive visceral leishmaniasis reveals mixed expression of type 1 and type 2 cytokine-responsive genes

Background The Syrian golden hamster (Mesocricetus aureus) has been used as a model to study infections caused by a number of human pathogens. Studies of immunopathogenesis in hamster infection models are challenging because of the limited availability of reagents needed to define cellular and molecular determinants.
Detector noise induced by ultra-fast laser

Irradiation of a photodetector by very short laser pulses was presented as a technique that can remotely alter detector's performance [1]. Recent experimental data demonstrated that energy of femto-second laser pulse transforms almost entirely into thermal energy. Thermal energy may inflict long-lasted changes in the detector that based on lattice structural changes or disorder [2], and semiconductor compound heats up. Those changes may result in detector's responsivity change - to induce a spectral shift that may prevent detection at specific wavelengths and in overall noise increase. Both phenomena may contribute into ultimately non-compensated losses in detectivity. Effect completely reversible if energy level is below energy threshold for melting E th -therefore integrity of the photodetector is protected during the alteration. In the paper we demonstrate that much longer laser pulses can be used to inflict similar effects in photo- detectors. Laser pulse can be arranged in such a way that combination of energy per pulse, repetition rate, pulse dwell time and duty cycle will not destroy detector or generate signal, but just inflict responsivity shift and noise variance increase. Technique of noise generation by ultra-fast laser is described and analyzed in details with respect to newly presented experimental data.
Treating Total Liquid Refusal with Backward Chaining and Fading.

In this study, we report on a 12-year-old boy with autism, mental retardation, and a history of severe gastrointestinal problems who presented with total liquid and food refusal. Backward chaining was used to shape drinking from a cup, and a fading procedure was used to increase the quantity of water he was required to drink.
The role of market and technological knowledge in recognizing entrepreneurial opportunities

Purpose – Opportunity recognition is an important aspect on entrepreneurship, especially for technology‐based ventures. Drawing on Austrian economic theory, recent studies have emphasized the importance of market knowledge in opportunity recognition. Although insightful, these studies do not take account of relationships that exist between different types of knowledge (e.g. technology and market knowledge). The authors aim to address this gap by integrating the Schumpeterian theory of opportunity development with Kirzner's theory of opportunity discovery to examine these relationships.Design/methodology/approach – The data consist of a longitudinal sample of 42 new biotechnology ventures from the USA, Finland, and Sweden.Findings – The paper finds that both market knowledge and technological knowledge (measured as the number of patents) contribute to firms' subsequent recognition of entrepreneurial opportunities.Originality/value – The results show the value and importance of early market knowledge and te...
Decision analysis and optimality in air traffic control conflict resolution: II. Optimal heading (vectoring) control in a linear planar configuration

Abstract This manuscript is concerned with the effects of a heading advisory dispensed by an air traffic controller on a resolution of a pending or an in-progress potential aerial conflict. It is assumed that the aircraft traverse two linear, planar, intersecting air routes with fixed velocities. A potential conflict is defined as a violation of a given safety distance between two airplanes traveling different paths. The controller, upon discerning that the two craft are in potential conflict or about to enter one, issues, at the appropriate instant, corrective vectoring to them in order to obtain an effective dissolution of the conflict. The interpretation of “effective” in this paper is construed as either of the following: a new direction is put forth by the controller so as to maintain an inviolable separation between the two planes while introducing a minimal disturbance to their flight paths, or alternatively, while minimizing the duration of the potential conflict. An analysis of the impact of the controller's instructions on a single conflict involving two planes only, accompanied with illustrative numerical examples, is carried out under two pilot response suppositions. The first stipulates that pilots execute precisely the controller's remedial commands whereas the second allows for a built-in randomness in their response time.
The Initial Immune Reaction to a New Tumor Antigen Is Always Stimulatory and Probably Necessary for the Tumor's Growth

All nascent neoplasms probably elicit at least a weak immune reaction. However, the initial effect of the weak immune reaction on a nascent tumor is always stimulatory rather than inhibitory to tumor growth, assuming only that exposure to the tumor antigens did not antedate the initiation of the neoplasm (as may occur in some virally induced tumors). This conclusion derives from the observation that the relationship between the magnitude of an adaptive immune reaction and tumor growth is not linear but varies such that while large quantities of antitumor immune reactants tend to inhibit tumor growth, smaller quantities of the same reactants are, for unknown reasons, stimulatory. Any immune reaction must presumably be small before it can become large; hence the initial reaction to the first presentation of a tumor antigen must always be small and in the stimulatory portion of this nonlinear relationship. In mouse-skin carcinogenesis experiments it was found that premalignant papillomas were variously immunogenic, but that the carcinomas that arose in them were, presumably because of induced immune tolerance, nonimmunogenic in the animal of origin.
Neurogenic tumors of the cervical vagus nerve: report of four cases and review of the literature.

Objective and importance Nerve sheath tumors arising from the cervical vagus nerve are extremely rare. These tumors most often present as asymptomatic, slowly enlarging, lateral neck masses and therefore often come initially to the attention of otolaryngologists and general surgeons. Because they are nerve tumors, however, neurosurgeons must be able to recognize and treat these rare entities. We report three cases of schwannoma and one case of neurofibroma of the cervical vagus nerve that were encountered at our center (Louisiana State University Medical Center) during a 31-year period. Clinical presentation The patients ranged from 31 to 61 years of age at the time of presentation to Louisiana State University Medical Center. Presenting complaints included hoarseness, Horner's syndrome, and palpation of an enlarging, asymptomatic, cervical mass. Reviews of systems revealed episodes of aspiration for one patient and frequent respiratory illnesses for two patients. These episodes were possibly related to their tumors. Imaging studies demonstrated well-circumscribed masses in the region of the carotid sheath. Intervention Using microsurgical techniques, gross total resection of all four tumors was accomplished. For one patient, the vagus nerve needed to be divided and an end-to-end anastomosis was performed. For the other three patients, resection of the tumor was achieved with the vagus nerve in continuity. Conclusion Vagal nerve schwannomas and neurofibromas in the neck are rare neoplasms. We present four cases of these benign tumors. The pathological features, epidemiological characteristics, presentation, differential diagnosis, and management are discussed. Gross total resection with preservation of the vagus nerve remains the treatment of choice.
Tip-Based Hybrid Simulation Study of Frictional Properties of Self-Assembled Monolayers: Effects of Chain Length, Terminal Group, Scan Direction, and Scan Velocity

We report a study of the frictional properties of alkanethiol self-assembled monolayers (SAMs) on Au(111) at room temperature using hybrid molecular simulations at the atomic force/frictional force microscopy (AFM/FFM) experimental time scale. Various parameters influencing frictional properties were investigated, including chain length, terminal group, scan direction, and scan velocity. Simulation results show that frictional force decreases with an increase of chain length and that hydrophilic −OH-terminated SAMs have higher frictional force than hydrophobic −CH3-terminated SAMs. Frictional force as a function of normal load exhibits different behaviors for −CH3- and −OH-terminated SAMs. Simulation results further show friction anisotropy on SAMs at low and high temperatures. Frictional force is the smallest when scanned along the tilt direction, the largest when scanned against the tilt direction, and between when scanned perpendicular to the tilt direction. Finally, simulation results also show the de...
On a key postulate of T-cell receptor restrictive function: the V-gene loci act as a single pool encoding recognition of the polymorphic alleles of the species major histocompatibility complex.

The proposition that single Vα or Vβ gene segments specify the recognition of the allele-specific determinants expressed on the major histocompatibility complex-encoded restricting elements of the species has as its consequence a totally different picture of the functioning of the T-cell receptor. This commentary justifies this assumption and outlines some of its most important consequences.