cssi/SciSciGPT-SciSciNet huggingface dataset:
A new implicit backward mid-point rule for highly-stiff systems of ordinary differential equations

Abstract A new implicit, L-stable, second-order method for the integration of highly-stiff ODE systems is developed. The new method is based on the general mid-point rule and is shown to be more efficient than the classical implicit mid-point rule when low or intermediate accuracy is desired. The new method, which has second-order accuracy, has better stability characteristics (in terms of damping) than the first-order backward Euler method. In addition, the use of global extrapolation is shown to improve the global accuracy and efficiency of the new method and to offer good conservative global error estimates.
New York University: description of the PROTEUS system as used for MUC-3

The Proteus system which we have used for MUC-5 is largely unchanged from that used for MUC-3 and MUC-4. It has three main components: a syntactic analyzer, a semantic analyzer, and a template generator.
Corpectomy and Stabilization with Methylmethacrylate in Patients with Metastatic Disease of the Spine: A Technical Note

Corpectomy with methylmethacrylate reconstruction and stabilization in patients with metastatic disease of the spine has been performed for several years. Stainless steel Steinmann pins or K-wires are commonly used to facilitate fixation of the acrylic to the vertebral bodies above and below the resection site. The use of these ferromagnetic substances precludes the optimal use of magnetic resonance imaging in the postoperative period. We now report the use of commercially available titanium screws in conjunction with the methylmethacrylate to eliminate this problem and provide for improved postoperative imaging.
Second order necessary conditions for optimal control problems with control and integral constraints

An optimal control problem containing restrictions on control variables and integral equality and inequality constraints is considered. A relatively simple and self-contained method for deriving new second order necessary conditions for such problems is presented. The new conditions derived here generalize some of the results reported in [3], [6], [9]. The method developed is quite general and is also applicable to optimal control problems including state or mixed state-control inequality constraints and to optimal control problems governed by partial differential equations.
Virtual testing of distance protection

Distance relays are the most commonly used protection devices in transmission systems. They require testing during different stages of relay development, commissioning, maintenance, configuration and operation analysis. The paper analyses the requirements for testing of distance relays under different abnormal conditions. It describes the conventional methods of testing and introduces a new method for virtual testing of distance relays. The virtual relay concept is described with several examples. Different applications of virtual relay testing and their advantages over conventional testing are presented at the end of the paper.
Wanted: correlates of vaccine-induced protection against simian immunodeficiency virus.

PURPOSE OF REVIEW We will highlight recent advances in defining the attributes of immune responses that control AIDS virus replication using animal models, and also point out key gaps in our understanding that should be addressed in future research. RECENT FINDINGS Many different vaccine approaches are currently being evaluated in animal models. Almost all of them elicit strong cellular or humoral immune responses in macaques. Commonly used prime-and-boost strategies have had varying degrees of success in diminishing chronic phase virus loads in vaccinated animals, but few have shown durable reduction in replication of the CCR5-tropic simian immunodeficiency viruses (SIVs) that most closely resemble field isolates of HIV. Investigators are therefore turning to other systems, including live attenuated vaccines and cohorts of spontaneous SIV controllers, to help identify the properties of successful host responses to pathogenic SIV. These responses likely incorporate multiple coordinated effector mechanisms. SUMMARY There is no effective AIDS vaccine on the horizon. CD4+ and CD8+ T cell responses and antibodies have all been implicated in control of SIV replication seen in various experimental systems, but the correlates of protection against AIDS virus replication have not yet been definitively identified. Animal models will remain a necessary component of this research.
Source apportionment of fine particulate matter in Houston, TX, using organic molecular markers

Abstract Using ambient concentrations of molecular markers, chemical mass balancing calculations have been performed to estimate the contribution of source categories to ambient fine particle levels at four sites in Houston, TX. Eight source profiles obtained using analytical methods equivalent to the techniques used in analysis of the ambient sample were used for the calculations. The chemical mass balancing model accurately reconstructed the measured concentrations of 24 molecular markers and three fine particle chemical components to estimate the contribution of each source to ambient fine particle loads. The results show that at three sites in the Houston urban area, diesel exhausts contribute between 1.6 and 3.7 μg m −3 to ambient fine particle levels, while at an upwind background site, diesel exhausts represent 0.5 μg m −3 of ambient fine particulate matter. Other important sources include gasoline-powered vehicles (1.1–2.8 μg m −3 at three urban sites and 0.5 μg m −3 at the background site); paved road dusts (1.0–2.8 μg m −3 urban and 0.1 μg m −3 background); meat cooking operations (0.9–1.3 μg m −3 urban and 0.7 μg m −3 background) and wood combustion (0.2–0.3 μg m −3 urban and −3 background). At one site located near the highly industrialized Houston Ship Channel, fuel oil combustion contributed an estimated 1.5 μg m −3 , while fuel oil combustion was not an important contribution at the other sites. Model runs using seasonally averaged data showed a high variation in source strength between seasons for some sources (i.e. paved road dusts much higher in the spring and summer than in the winter), while other sources showed little or no seasonal variation (i.e. vehicle exhausts and meat cooking operations).
Shallow and deep level defects in GaN

Shallow and deep electronic defects in MOCVD-grown GaN were characterized by variable temperature Hall effect measurements, deep level transient spectroscopy (DLTS) and photoemission capacitance transient spectroscopy (O-DLTS). Unintentionally and Si-doped, n-type and Mg-doped, p-type GaN films were studied. Si introduces a shallow donor level into the band gap of GaN at ∼Ec - 0.02 eV and was found to be the dominant donor impurity in our unintentionally doped material. Mg is the shallowest acceptor in GaN identified to date with an electronic level at ∼Ev + 0.2 eV. With DLTS deep levels were detected in n-type and p-type GaN and with O-DLTS we demonstrate several deep levels with optical threshold energies for electron photoemission in the range between 0.87 and 1.59 eV in n-type GaN.
Perceptions of Time Spent in Teacher Talk: A Comparison Among Self-Estimates, Peer Estimates, and Actual Time

The purpose of this study was to examine and compare self-estimates, peer estimates, and actual time preservice teachers spent talking in rehearsal. Participants (N = 32) conducted a short choral r...
A literature review of professionalism in surgical education: suggested components for development of a curriculum.

Background While it is evident that a surgeon must master medical knowledge and technical skill, there are other "soft skills" that are essential to a successful surgeon. One of these skills is professionalism . The challenge in surgical education lies in developing an effective professionalism curriculum and a related method of evaluation. Objective Our review updates the literature and provides recommendations for improving instruction and evaluation of professionalism. Design A literature review was conducted using PubMed , Google Scholar , and Web of Knowledge . We restricted our search to documents published from 2009 to 2012 that address methods of teaching and tools for assessing professionalism in surgical education. Results Sixty-three documents were reviewed, with 14 fitting our search criteria for professionalism in surgical education completely. Other articles focused on the topics of professionalism in surgery, medical professionalism, and professionalism education in medical specialties other than surgery. Conclusions Development of a professionalism curriculum for surgical residents might begin with defining professionalism in terms of tangible behaviors. The program might also include a precurriculum preparatory course and simulation-based training. Residency programs must also maintain professionalism among its faculty. Assessment in the form of multisource feedback that is consistent with observable behavioral definitions of professionalism should also be considered in evaluating resident professionalism.
Recognition and recall in short-term memory

Abstract A signal detection analysis of confidence judgments in short-term memory was used to investigate the difference in the amount of information required in memory for recognition and recall. In yoked recognition and recall experiments, subjects learned lists of five paired-associates and were probe-tested for one of them either by a recall or yes-no recognition procedure. This method permitted examination of the effect of serial position on the obtained differences in information in memory.
Simultaneous Prediction Intervals to Contain the Standard Deviations or Ranges of Future Samples from a Normal Distribution

Abstract This article provides procedures for constructing simultaneous prediction intervals to contain the standard deviations or ranges of all of k future samples, given the standard deviation or range of a past sample from the same normal distribution. The procedures, which use mainly existing tabulations, are illustrated by a numerical example.
PLEIADES: high peak brightness, subpicosecond Thomson hard x-ray source

The Picosecond Laser-Electron Inter-Action for the Dynamic Evaluation of Structures (PLEIADES) facility, is a unique, novel, tunable (10-200 keV), ultrafast (ps-fs), hard x-ray source that greatly extends the parameter range reached by existing 3rd generation sources, both in terms of x-ray energy range, pulse duration, and peak brightness at high energies. First light was observed at 70 keV early in 2003, and the experimental data agrees with 3D codes developed at LLNL. The x-rays are generated by the interaction of a 50 fs Fourier-transform-limited laser pulse produced by the TW-class FALCON CPA laser and a highly focused, relativistic (20-100 MeV), high brightness (1 nC, 0.3-5 ps, 5 mm.mrad, 0.2% energy spread) photo-electron bunch. The resulting x-ray brightness is expected to exceed 10{sup 20} ph/mm{sup 2}/s/mrad{sup 2}/0.1% BW. The beam is well-collimated (10 mrad divergence over the full spectrum, 1 mrad for a single color), and the source is a unique tool for time-resolved dynamic measurements in matter, including high-Z materials.
Oligomerization of endogenous and synthetic amyloid beta-protein at nanomolar levels in cell culture and stabilization of monomer by Congo red.

Amyloid β-proteins (Aβ) are proteolytic fragments of the β-amyloid precursor protein (βAPP) that are secreted by mammalian cells throughout life but also accumulate progressively as insoluble cerebral aggregates in Alzheimer's disease (AD). Because mounting evidence indicates that Aβ aggregation and deposition are early, critical features of AD leading to neurotoxicity, many studies of Aβ aggregation have been conducted using synthetic peptides under generally nonphysiological conditions and concentrations. We recently described the oligomerization of Aβ peptides secreted by βAPP-expressing cells at low nanomolar (20−30 ng/mL) levels into sodium dodecyl sulfate- (SDS-) stable oligomers of 6−16 kDa. Here, we extensively characterize this in vitro system and show that the amyloid binding dye, Congo red, acts to markedly decrease oligomer/monomer ratios by stabilizing the 4 kDa Aβ monomers (ID50 ≅ 3.4 μM). Addition of radioiodinated synthetic Aβ1-40 to the cultures or to their conditioned media at physiologi...
Magnetic-amplifier circuits with full-wave output and half-wave control signals

THE advantages of half-wave magnetic-amplifier circuits of the flux reset type have been described in several papers.1,2 However, when several such amplifiers are cascaded and the output is used to drive a servomotor, the output often is allowed to be a half-wave.3 This sort of output has proved satisfactory for either d-c motors or 2-phase a-c motors if a small derating of the motor output is accepted.
The participation of 1- and 2-isomers of O-alkylglycerols as acyl acceptors in cell-free systems

Abstract Cell-free homogenates from several neoplastic tissues and normal rat liver contain enzymes that acylate O -alkylglycerols. Acylation of rac-1- O -alkylglycerols produced only 1-alkyl-3-acylglycerols, whereas the acylation of 2-alkylglycerols produced 1,3-diacyl-2-alkylglycerols; neither of the isomeric forms of the alkylglycerols was phosphorylated. ATP, CoA, and Mg 2+ were required as cofactors for acylation.
Auditory discrimination: role of time and intensity in the precedence effect.

Rats were trained to respond on a lever adjacent to a sounding speaker (the sound source) when a single click was emitted. A second click (the artificial echo) was presented through a second speaker on the opposite side. In Condition I, the echo (equal in intensity to the source) was delayed from .015 to 32 milliseconds; greater than 75% correct responses were given for delay times between about .040 milliseconds (lower threshold) and 8 milliseconds (upper threshold). In Condition II, the echo (simultaneous with the source) was reduced in intensity relative to the source over a range from 2.5 decibels to 40 decibels; greater than 75% correct responses occurred for intensity reductions greater than 5 decibels. In Condition III, both the intensity and the delay time of the echo were manipulated in a manner analogous to that which would occur under natural conditions; greater than 95% correct responses were given for delay times from 1 to 32 milliseconds. These data indicate that both time and intensity differences are necessary for localization of primary sources, with delay time contributing more at short echo path distances, and intensity differences at long distances.
Kappa opioid receptor-mediated regulation of prolactin and a-melanocyte-stimulating hormone secretion in male and female rats

The purpose of this study was to examine the effects of the kappa opioid receptor agonist U-50,488 and antagonist nor-binaltorphimine (NOR-BNI) on the secretion of prolactin and alpha-melanocyte-stimulating hormone (alpha MSH) in male and female rats. Activation of kappa opioid receptors with U-50,488 increased plasma prolactin concentrations in both male and female rats, whereas blockade of kappa opioid receptors with NOR-BNI decreased plasma prolactin concentrations in male, but not in female rats. U-50,488 also increased and NOR-BNI decreased plasma concentrations of alpha MSH; similar effects were observed in both male and female rats. These results reveal a sexual difference in kappa opioid receptor-mediated regulation of prolactin, but not alpha MSH secretion.
Transesophageal echocardiographic recognition of subaortic complications in aortic valve endocarditis. Clinical and surgical implications.

BACKGROUNDSecondary involvement of the mitral-aortic intervalvular fibrosa and the anterior mitral leaflet (subaortic structures) can occur in patients with aortic valve endocarditis. The secondary involvement of these structures occurs as a result of direct extension of the infection from the aortic valve or as a result of an infected aortic regurgitant jet striking the ventricular surfaces of the mitral-aortic intervalvular fibrosa and the anterior mitral leaflet. The abscess of mitral-aortic intervalvular fibrosa can expand to form an aneurysm. Subsequently, this mitral-aortic intervalvular fibrosa aneurysm can develop a perforation and communicate with the left atrium, resulting in the systolic regurgitation of blood from the left ventricular outflow tract into the left atrium. Secondary infection can also occur on the ventricular surface of the anterior mitral leaflet and result in the formation of an aneurysm or perforation of anterior mitral leaflet.METHODS AND RESULTSThis study examines the utilit...
Rate of induced forward mutation at 3 genetic loci in Salmonella typhimurium

The rate of forward mutation to 8-azaguanine, 5-fluorouracil and azetidine carboxylic acid resistance was measured in Salmonella typhimurium following treatment with 18 chemical mutagens. Although the absolute frequency of both spontaneous and chemically-induced mutation was different at the markers scored, the 3 selection systems were found to be equisensitive: each system produced a statistically significant response at approximately the same mutagen concentration. This result suggests that in Salmonella the target size present in a given forward mutation assay is sufficiently large to approximate the level of mutation occurring elsewhere in the chromosome in sections of DNA of similar size.
From technological potential to product performance: an empirical analysis

Abstract RD the second measures the extent to which this potential is translated into acual or ‘realized’ system performance, and probes wether the fundamental technologies employed are well integrated with theirapplication context. We apply these measures to empirical data from the global computer industry. We find that technological potential is related to depth in specialized research, while technological yield is associated with the process for technology integration. The analysis therefore shows that the products mirror the organization that conceived them—‘integrated’ products are correlated with organizational processes aimed at ‘integration’. The findings have significant implications for the design of R&D organizations and processes.
Ly-A and Ly-B: two systems of lymphocyte isoantigens in the mouse.

Two systems of isoantigens confined to thymocytes and lymphocytes have been defined in the mouse by cytotoxic isoantisera. The two genetic loci have been designated Ly-A and Ly-B. Typing of 25 mouse strains and sublines indicates that each system comprises only 2 alleles, determining alternative isoantigens Ly-A. 1 or Ly-A. 2, and Ly-B. 1 or Ly-B. 2, respectively. There is no evidence of multiple alleles or that either locus is compound. Tests for genetic linkage were performed by serological typing of mice from segregating generations. None of the four loci H-2 (group IX), $\theta $, Ly-A and Ly-B is closely linked to any other of the four. Ly antigens are found in high concentration on thymocytes and in lesser amounts on lymphocytes. The small absorptive capacity of bone marrow cell suspensions is probably due to the presence of mature lymphocytes rather than thymocyte-lymphocyte precursors, which according to preliminary evidence lack Ly antigens. Ly-B. 1 is exceptional in that the disparity between thymocytes and lymphocytes in content of antigen is greater than that of the three other antigens. When Ly antiserum is injected into mice of the relevant Ly type, under conditions which give complete absorption of H-2 antibody in vivo, Ly antibody is not extensively absorbed; this is to be expected from the limited tissue distribution of Ly antigens. Absorption of Ly and $\theta $ iosantibodies in vivo is reduced by treatment of the recipients with cortisone or lethal total-body irradiation. The reduction in titre of Ly and $\theta $ antibodies in such mice may be no more than that resulting from dilution. Absorption of injected H-2 antibody also may be reduced by treatment of the recipients with cortisone but in this case the effect of cortisone does not approach the virtual abolition of absorption that is seen with Ly and $\theta $ antibodies. The thymocytes and lymphocytes of chimeras formed by restoring lethally irradiated mice with allogeneic bone marrow have the Ly-A type, Ly-B type and $\theta $ type of the donor. The content of Ly antigens on cells of different leukaemias varies widely and shows no correlation with presence or absence of TL (thymus-leukaemia) antigen; TL+ leukaemias may be Ly- or Ly+ and TL- leukaemias may be Ly- or Ly+. Five systems of isoantigens are now demonstrable on mouse thymocytes by means of cytotoxic isoantisera. Of these, TL is an exclusively thymic antigen. Ly-A and Ly-B antigens occur also on lymphocytes. $\theta $ occurs on thymocytes, on lymphocytes, and in brain. The fifth antigen, H-2, is still more widely distributed and differs from the other four in being represented less strongly on thymocytes than on lymphocytes.
Normal Pulse Voltammetry: In Situ Kinetic Analysis of Proton Exchange Membrane Fuel Cells

Normal pulse voltammetry (NPV) is applied to operating proton exchange membrane fuel cells (PEMFCs) using a high current potentiostat. Kinetic information including the Tafel slope and exchange current density for the oxygen reduction reaction (ORR) is directly extracted from the steady state voltammetric response obtained from the NPV experiment. Temperature, relative humidity, and conditioning potential are varied independently to observe their effect on the PEMFC through the Tafel slope calculation. This NPV technique provides kinetic information previously collected through ex situ techniques such as rotating disc electrodes. The ability to probe in situ the kinetic effects of catalysts within operational PEMFCs has never been proposed in this detail. NPV measurements take less than 30 seconds to conduct thus making the process simple and efficient. The observed Tafel slope is about 60mV/decade for oxide covered platinum and 120mV/decade for oxide free platinum.
L-deprenyl-induced increase in IL-2 and NK cell activity accompanies restoration of noradrenergic nerve fibers in the spleens of old F344 rats.

Abstract Previously, we have hypothesized a causal relationship between some measures of immunosenescence and the age-related decline in sympathetic noradrenergic (NA) nerve fibers in spleen and lymph nodes of F344 rats. In the present study, we investigated this interrelationship further by measuring NK cell activity, Con A-induced IL-2 production, norepinephrine (NE) concentration, and morphological localization of NA and neuropeptide-Y (NPY) nerve fibers in the spleens of old (21 months old) male F344 rats after 10 weeks of daily treatment with low doses of l -deprenyl, an irreversible monoamine oxidase-B inhibitor, followed by a 9-day wash-out period. NK cell activity and Con A-induced IL-2 production were increased in deprenyl-treated old rats in comparison to untreated and saline-treated old rats. Deprenyl treatment did not alter the percentage of CD5+ T-cells, but moderately increased the percentage of sIgM+ B-cells in the spleens of old rats. In addition to changes in immune responses, NE content and the volume density of NA and NPY nerve fibers were partially augmented in the spleens of deprenyl-treated old rats. In a separate study, various concentrations of deprenyl were added in vitro to spleen cells from young and old F344 rats to examine the direct effects of the drug on Con A-induced IL-2 production. In contrast to in vivo treatment, in vitro addition of deprenyl did not alter the Con A-induced IL-2 production by splenocytes from old rats. Together, these results suggest that the ability of deprenyl to enhance certain immune responses are interlinked to the restoration of sympathetic NA and NPY nerve fibers in the spleens of old rats.
Proof of stability and boundedness of a real-time motor resistance estimation and compensation scheme

This paper presents and proves the stability and boundedness of a scheme for estimation of one parameter in a complex nonlinear system. The proof presented in this paper does not assume discretised plant equations. This scheme is applied to estimate resistance of a brushless DC motor and compensate for the resistance change in real-time via feedback control. A non-dynamic motor inverse model, which neglects the electrical dynamics of the motor, is used to achieve torque control of the motor. Variations of the motor parameters, due to environmental factors, such as temperature, build variations, ageing, etc., directly impart inaccuracies in the motor control, and thus affect the performance of the system. Comparison of simulations for closed-loop voltage control of automotive electric power steering system actuator confirms a lower bound of error of the estimated parameter and faster adaptation with the proposed scheme compared to previously employed methods.
A smooth response surface algorithm for constructing a gene regulatory network

A smooth response surface (SRS) algorithm is developed as an elaborate data mining technique for analyzing gene expression data and constructing a gene regulatory network. A three-dimensional SRS i...
Periodic hormonogenesis--a new phenomenon. Periodicity in function of a hormone-producing tumor in man.

ABSTRACT Evidence for periodicity in adrenocortical production of cortisol and 17-ketosteroids was found during study of a patient with a very slow growing carcinoid-type malignant bronchial adenoma. The tumor caused adrenocortical hyperplasia and Cushing's syndrome as well as the superior vena caval syndrome. The large quantity of immunologically reactive ACTH found in the tumor as well as marked fluctuations in blood ACTH levels support the view that the periodicity in adrenal steroid production which was observed was due to periodicity in ACTH production by the tumor. The cyclical changes in cortisol production were of large magnitude and the peak-to-peak cycle length, as estimated during 2 cycles, was approximately 18 days. During the cycles, urinary 17-hydroxycorticosteroids (17-OHCS) varied from normal to as high as 150 mg/day. Cyclical variations in renal sodium excretion also occurred and were not related to the rate of 17-OHCS excretion or to aldosterone excretion. Aldosterone excretion rates wer...
CACC box and enhancer response of the human embryonic ε globin promoter

Abstract The functional interaction between the human e globin promoter and an erythroid-specific transcription enhancer, 5′ HS-2, has been analyzed by transient expression assay. While stepwise deletion of DNA sequences between −852 and −122 had only small effects, removal of the CACC box at position −111 greatly decreased e-globin promoter activity, as well as its response to the enhancer function of 5′ HS-2 in erythroid cells. Our data demonstrated that the three ubiquitous promoter elements, the CACC, CCAAT, and TATA boxes, of the e-globin-encoding gene together form a minimal promoter that would interact efficiently with 5′ HS-2, and that at least the CACC box is an essential functional component of this enhancer-promoter interaction.
Interfering with taste aversion learning in rats: the role of associative interference.

Six experiments with rats investigated the conditions under which one flavor interferes with aversion conditioning to a second, familiar flavor. Conditioning to the familiar flavor was weakest when the interference flavor was (1) contiguous to lithium-induced toxicosis, (2) novel, (3) more intense, and (4) strongly associated with toxicosis. In addition, conditioning to the familiar flavor was weakened even if multiple conditioning trials were used. The repeated finding of an inverse relationship between strength of aversion to the target and interference flavors is interpreted as support for an associative competition hypothesis of the interference effect. The possible relevance of the interference effect to the attenuation of taste aversions in cancer patients is discussed.
Changes in chloroplast DNA during development in tobacco, Medicago truncatula , pea, and maize

We examined the DNA from chloroplasts obtained from young and fully expanded leaves of tobacco (Nicotiana tabacum L.), Medicago truncatula, pea (Pisum sativum L.), and maize (Zea mays L.). The changes in plastid DNA content and structure were monitored by four independent methods: 4',6-diamidino-2-phenylindole (DAPI) staining with intact chloroplasts, in situ DAPI staining of cytological sections, ethidium bromide staining at the single-molecule level after exhaustive deproteinization of lysed chloroplasts, and pulsed-field gel electrophoresis. During leaf development, we found a decline of chloroplast DNA (cpDNA) in all four plants. For tobacco, for which plants can readily be regenerated from somatic cells, cpDNA persisted longer than in the other three plants. We also found a striking progression from complex multigenomic DNA molecules to simple subgenomic molecules during plastid development. Although the decrease in molecular size and complexity paralleled the decrease in DNA content per plastid, 6% of the chloroplasts in a fully expanded tobacco leaf still contained DNA in complex branched structure, whereas no such complex structures were found in mature leaves for the hard-to-regenerate maize.
Atomic layer controlled deposition of Al2O3 films employing trimethylaluminum (TMA) and H2O vapor

Sequential surface chemical reactions for the controlled deposition of Al2O3 films were studied using transmission Fourier transform infrared spectroscopy (FTIR). Experiments were performed in situ in an ultrahigh vacuum UHV chamber using high surface area alumina membranes. Trimethylaluminum [Al(CH3)3] (TMA) and H2O vapor were employed sequentially in an ABAB... binary fashion to achieve atomic layer controlled growth. An optimal Al2O3 growth procedure was established that employed TMA/H2O exposures at.3 Torr and 500 K. The experiments revealed that each reaction was self-terminating and atomic layer controlled growth was dictated by the surface chemistry. The controlled deposition of Al2O3 may be employed on silicon surfaces for the formation of high dielectric gate and passivation layers.
Fifty-year biogeochemical effects of green ash, white pine, and Norway spruce in a replicated experiment

Binkley, D. and Valentine, D., 1991. Fifty-year biogeochemical effects of green ash, white pine, and Norway spruce in a replicated experiment. For. Ecol. Manage., 40:13-25. Few long-term, replicated experiments are available to provide information on the effects of tree species on soil chemistry and ecosystem biogeochemistry. We examined replicated, 50-year-old plots of green ash (Fraxinus pennsylvanica Marsh), white pine (Pinus strobus L.), and Norway spruce [ Picea abies ( L. ) Karst. ] that had been planted in an abandoned agricultural field. The pHwater of the 0-5-cm soil layer under green ash was 4.6, compared with 4.2 under white pine and 3.8 under Norway spruce. The Norway spruce soil was substantially less-well buffered against further acidification than the soil under green ash, and contained less than half the quantity of exchangeable Ca 2 + + Mg 2 + + K + in the 0-15-cm depth. The decline in these cations under Norway spruce was accompanied by higher concentrations of exchangeable A13 +. The most important factor in the lower pH under Norway spruce was the greater acid strength of the soil organic matter, with a secondary role played by the higher saturation of the exchange complex with aluminum. Nitrogen mineralization in resin cores averaged 40 kg/ha under green ash, 84 kg/ha under white pine, and 56 kg/ha under Norway spruce. The only significant difference in litterfall biomass and chemistry was a greater content of aluminum and lower content of magnesium in litterfall in the Norway spruce plots relative to green ash plots. These major biogeochemical differences between tree species demonstrate the need for replicated experiments for assessing the mechanisms that drive long-term changes in ecosystems relative to differing species, management regimes, and atmospheric deposition.
Chiral phase transition for SU ( N ) gauge theories via an effective Lagrangian approach

We study the chiral phase transition for vectorlike $\mathrm{SU}(N)$ gauge theories as a function of the number of quark flavors ${N}_{f}$ by making use of an anomaly-induced effective potential. We modify an effective potential of a previous work, suggested for ${N}_{f}lN,$ and apply it to larger values of ${N}_{f}$ where the phase transition is expected to occur. The new effective potential depends explicitly on the full $\ensuremath{\beta}$ function and the anomalous dimension $\ensuremath{\gamma}$ of the quark mass operator. By using this potential we argue that chiral symmetry is restored for $\ensuremath{\gamma}l1.$ A perturbative computation of $\ensuremath{\gamma}$ then leads to an estimate of the critical value ${N}_{f}^{c}$ for the transition.
Anthropometric Variation and Health: A Biocultural Model of Human Growth

This review is a synthesis of the many strands of evidence for a biocultural model of human growth. The model allows us to better understand the causes of variation and plasticity in human growth and development. The model helps us to identify and ameliorate factors that impair health, growth, and development. The biocultural perspective focuses on the recurring interaction between the biology of human development and the sociocultural environment. Not only does the latter influence the former, but human developmental biology modifies social and cultural processes as well. There are two essential messages of this synthesis. First, the biocultural nature of human growth and development is best understood via a life history perspective. The second essential message is that neither biology nor culture has primacy in human development. Rather, both work simultaneously and subtly during all stages of life to produce human phenotypic variability. That variability leads to individual and population differences i...
Classical logics for attribute-value languages

This paper describes a classical logic for attribute-value (or feature description) languages which are used in unification grammar to describe a certain kind of linguistic object commonly called attribute-value structure (or feature structure). The algorithm which is used for deciding satisfiability of a feature description is based on a restricted deductive closure construction for sets of literals (atomic formulas and negated atomic formulas). In contrast to the Kasper/Rounds approach (cf. [Kasper/Rounds 90]), we can handle cyclicity, without the need for the introduction of complexity norms, as in [Johnson 88] and [Beierle/Pletat 88]. The deductive closure construction is the direct proof-theoretic correlate of the congruence closure algorithm (cf. [Nelson/Oppen 80]), if it were used in attribute-value languages for testing satisfiability of finite sets of literals.
Dislocation mechanics-based constitutive equations

A review of constitutive models based on the mechanics of dislocation motion is presented, with focus on the models of Zerilli and Armstrong and the critical influence of Armstrong on their development. The models were intended to be as simple as possible while still reproducing the behavior of real metals. The key feature of these models is their basis in the thermal activation theory propounded by Eyring in the 1930’s. The motion of dislocations is governed by thermal activation over potential barriers produced by obstacles, which may be the crystal lattice itself or other dislocations or defects. Typically, in bcc metals, the dislocation-lattice interaction is predominant, while in fcc metals, the dislocation-dislocation interaction is the most significant. When the dislocation-lattice interaction is predominant, the yield stress is temperature and strain rate sensitive, with essentially athermal strain hardening. When the dislocation-dislocation interaction is predominant, the yield stress is athermal, with a large temperature and rate sensitive strain hardening. In both cases, a significant part of the athermal stress is accounted for by grain size effects, and, in some materials, by the effects of deformation twinning. In addition, some simple strain hardening models are described, starting from a differential equation describing creation and annihilation of mobile dislocations. Finally, an application of thermal activation theory to polymeric materials is described.
Antagonism by l-glutamine of toxicity and growth inhibition caused by other amino acids in suspension cultures of Nicotiana silvestris

Abstract The toxicity of l -amino acids toward exponentially dividing cells of Nicotiana silvestris in suspension culture was monitored by following growth rates throughout a span of 8 days. Except for l -glutamine, all 19 protein amino acids inhibited cell growth. Inhibition progressed with an initial stage of slowed exponential growth. Cells in this stage were receptive to complete recovery under some conditions. Otherwise an irreversible stage of total growth inhibition and progressive cell deterioration followed. Electron microscopy showed that amino acids triggered a state of cell shrinkage which eventually degenerated to total cellular disorganization. An apparent exocytotic deposition of condensed and blackened cellular debris occurred between the cell wall and plasmalemma. l -Glutamine was not only an effective agent for prevention of amino acid toxicity, but enhanced the final growth yield. l -Glutamine also was able to completely reverse inhibitor effects in cells which had been in the slowed exponential phase for up to 3 days. We propose that any amino acid inhibition which can be completely antagonized by l -glutamine be called ‘general amino acid inhibition’. ‘Specific amino acid inhibition’, resulting from particular pathway imbalances caused by certain exogenous amino acids, can be recognized and studied in the presence of l -glutamine which abolishes the complicating effects of general amino acid inhibition. It is hypothesized that the l -glutamine: amino-acid ratio established in vivo might influence susceptibility to apoptosis, a eukaryotic process of programmed cell death which has been characterized most extensively in animals.
Improving efficient marginal estimators in bivariate models with parametric marginals

Suppose we have data from a bivariate model with parametric marginals. Efficient estimators of the parameters in the marginal models are generally not efficient in the bivariate model. In this article, we propose a method of improving these marginal estimators and demonstrate that the magnitude of this improvement can be as large as 100 percent in some cases.
Shear Stress Stimulates Phosphorylation of Endothelial Nitric-oxide Synthase at Ser1179 by Akt-independent Mechanisms ROLE OF PROTEIN KINASE A

Recently, we have shown that shear stress stimulates NO(*) production by the protein kinase B/Akt (Akt)-dependent mechanisms in bovine aortic endothelial cells (BAEC) (Go, Y. M., Boo, Y. C., Park, H., Maland, M. C., Patel, R., Pritchard, K. A., Jr., Fujio, Y., Walsh, K., Darley-Usmar, V., and Jo, H. (2001) J. Appl. Physiol. 91, 1574-1581). Akt has been believed to regulate shear-dependent production of NO(*) by directly phosphorylating endothelial nitric-oxide synthase (eNOS) at the Ser(1179) residue (eNOS-S(1179)), but a critical evaluation using specific inhibitors or dominant negative mutants (Akt(AA) or Akt(AAA)) has not been reported. In addition, other kinases, including protein kinase A (PKA) and AMP kinase have also shown to phosphorylate eNOS-S(1179). Here, we show that shear-dependent phosphorylation of eNOS-S(1179) is mediated by an Akt-independent, but a PKA-dependent, mechanism. Expression of Akt(AA) or Akt(AAA) in BAEC by using recombinant adenoviral constructs inhibited phosphorylation of eNOS-S(1179) if cells were stimulated by vascular endothelial growth factor (VEGF), but not by shear stress. As shown before, expression of Akt(AA) inhibited shear-dependent NO(*) production, suggesting that Akt is still an important regulator in NO production. Further studies showed that a selective inhibitor of PKA, H89, inhibited shear-dependent phosphorylation of eNOS-S(1179) and NO(*) production. In contrast, H89 did not inhibit phosphorylation of eNOS-S(1179) induced by expressing a constitutively active Akt mutant (Akt(Myr)) in BAEC, showing that the inhibitor did not affect the Akt pathway. 8-Bromo-cAMP alone phosphorylated eNOS-S(1179) within 5 min without activating Akt, in an H89-sensitive manner. Collectively, these results demonstrate that shear stimulates phosphorylation of eNOS-S(1179) in a PKA-dependent, but Aktindependent manner, whereas the NO(*) production is regulated by the mechanisms dependent on both PKA and Akt. A coordinated interaction between Akt and PKA may be an important mechanism by which eNOS activity is regulated in response to physiological stimuli such as shear stress.
Ein Ru5Mo2-Heterometallcluster mit zwei vierfach-überbrückenden Carbonylliganden

[Ru 4 Mo 2 (CO) 13 (μ 4 -η 2 -CO)(μ 4 -S)(C 5 H 5 ) 2 ] cristallise avec le groupe d'espace P2 1/c (R=0,029). [Ru 5 Mo 2 (CO) 14 (μ 4 -η 2 -CO) 2 (μ 4 -S)(C 5 H 5 ) 2 ] cristallise avec le groupe d'espace P2 1/m (R=0,040)
Mythico-History, Social Memory, and Praxis: Anthropological Approaches and Directions

This article explores the interface and tension between myth, history, and memory, in relation to ideology and praxis of identity. There is a critical overview of anthropological and other approaches in the humanities and social sciences to ‘mythico-history’ and social memory, their mutual influences, and current debates and directions in this literature. In particular, emphasis is upon the uses of oral narratives in historiography and social context in the constructions of personal and collective identities of difference, for example, ethnicity and gender in ‘narratives of nation’ and ‘myths of matriliny’ and their connections to social practice, drawing on secondary cross-cultural data and primary data from this anthropologist's research in Tuareg (Kel Tamajaq) communities of northern Niger and Mali.
On the development of increasing surface roughness during ion sputtering

Abstract A simple statistical model has been developed to explain the development of surface topography (roughness) during ion sputtering of solid targets. The square root depth dependence of the surface roughness is explained by assuming that the roughness is caused by the differences in sputtering rates obtained on differently oriented crystallographic surfaces, and that the distribution of the sputtering rates is fully random. Deviations from the random distribution of the sputtering rate lead to different types of depth dependence of the surface roughness.
In Vitro Activity of Netilmicin Compared with Gentamicin, Tobramycin, Amikacin, and Kanamycin

Abstract The in vitro activity of netilmicin was compared with that of gentamicin, tobramycin, amikacin, and kanamycin against 636 strains of bacteria recently isolated from clinical sources. Gentamicin was the most active antibiotic, but netilmicin and tobramycin closely paralleled it. Netilmicin was generally four-to eightfold less active than gentamicin against Serratia and group A streptococci, and was twofold less active against Pseudomonas aeruginosa. When effects of inoculum size and concentration of divalent cations in the media were evaluated, netilmicin was shown to be similar to gentamicin in vitro. Minimum inhibitory concentrations for P. aeruginosa were increased as much as 18-fold when the Mg2+ and Ca2+ concentrations were increased to physiological levels in Mueller-Hinton broth.
The Continuum Slope of Mars: Bidirectional Reflectance Investigations and Applications to Olympus Mons

Two primary causes of near-IR continuum slope variations have been observed in an investigation of the bidirectional reflectance characteristics of ferric coatings on the continuum slope of Mars. First, the presence of a thin ferric coating on a dark substrate produces a negative continuum slope due to the wavelength-dependent transparency of the ferric coating. Second, wavelength-dependent directional reflectance occurs when the surface particles are tightly packed, particle sizes are on the order of or smaller than the wavelength of light, or the surface is otherwise smooth on the order of the wavelength of light. Based on these results, the annuli on the flanks of Olympus Mons which are defined by reflectance and continuum slope are consistent with spatial variations in surface texture and possibly with spatial variations in the thickness of a ferric dust coating or rind.
Optical Beam Propagation through the Oceanic Turbulence

Effect of oceanic turbulence on spectrum, intensity, coherence and polarization of monochromatic and random beams is investigated on the basis of temperature-salinity power spectrum of ocean and extended Huygens-Fresnel integral.
Respiratory Motion in Positron Emission Tomography/Computed Tomography: A Review

The development of positron emission tomography/computed tomography (PET/CT) scanners has allowed not only straightforward but also synergistic fusion of anatomical and functional information. Combined PET/CT imaging yields an increased sensitivity and specificity beyond that which either of the 2 modalities possesses separately and therefore provides improved diagnostic accuracy. Because attenuation correction in PET is performed with the use of CT images, with CT used in the localization of disease, accurate spatial registration of PET and CT image sets is required. Correcting for the spatial mismatch caused by respiratory motion represents a particular challenge for the requisite registration accuracy as a result of differences in temporal resolution between the 2 modalities. This review provides a brief summary of the materials, methods, and results involved in multiple investigations of the correction for respiratory motion in PET/CT imaging of the thorax, with the goal of improving image quality and quantitation. Although some schemes use respiratory-phase data selection to exclude motion artifacts, others have adopted sophisticated software techniques. The various image artifacts associated with breathing motion are also described.
Neurochemical Architecture of the Human Striatum

The striatum of the human brain has a highly differentiated neurochemical architecture visible in stains for many of the neurotransmitter-related molecules present in the striatum. The distributions for these chemical markers have never been analyzed comprehensively. We compared the distributions of multiple neurochemical markers in a serial-section analysis of the caudate nucleus, the putamen, and the ventral striatum in normal human brains. The cholinergic system was identified with choline acetyltransferase (ChAT). The organization of the cholinergic fiber system was compared with that of striatal systems expressing immunoreactivity for calbindin D28k, met-enkephalin, substance P, tyrosine hydroxylase, and parvalbumin. Each striatal region analyzed displayed a unique neurochemical organization. In the dorsal caudate nucleus, the distribution of all markers followed the classical striosome/matrix organization as previously reported. In the dorsal putamen, ChAT-staining was less intense, and striosomes were delineated primarily by unstained fiber bundles. In the ventral caudate nucleus/nucleus accumbens region, the boundaries of ChAT-stained regions were not always visible with stains for calbindin, enkephalin, and substance P. The ventral putamen displayed a similar organization, except in its lateral part, where ChAT-poor regions were often found adjacent to, rather than in register with, regions expressing low levels of the other markers (calbindin, enkephalin, substance P, and tyrosine hydroxylase). Our findings suggest that, in addition to the classical striosome-matrix organization visible in the dorsal caudate nucleus and putamen, there is further neurochemical differentiation in a large ventral part of the caudate nucleus and putamen and in the ventral striatum-nucleus accumbens proper. The more complex relationships among the different neurochemical systems in the ventral striatum may reflect the increase in size in the primate of striatal regions associated with association and limbic cortex.