cssi/SciSciGPT-SciSciNet huggingface dataset:
Power conversion techniques for portable EMI sensitive applications

In circuit applications that demand low noise, such as in many portable wireless devices, there is a need to optimize circuit design in power converter circuits. The path to low noise performance does not necessarily require exotic circuit techniques or the latest IC features. Conventional low noise power supply techniques are "tweaked" to improve the performance of DC/DC conversion circuits. A series of improved circuit designs are outlined such as redesigns in push-pull converters, the use of negative railing, the usage of charge pumps (also known as inductorless design), single resistance-capacitance filter, and PCB ground layout. The design techniques are explained and sample circuits are shown. Noise measurements of such re-designed circuits are performed with the improved results explained. Some final attention is paid to pitfalls occurring from using digital layout design hardware in the use of mostly analog layout methods in power conversion circuits.
Generalized Quantifiers and Number Sense

Generalized quantifiers are functions from pairs of properties to truth-values; these functions can be used to interpret natural language quantifiers. The space of such functions is vast and a great deal of research has sought to find natural constraints on the functions that interpret determiners and create quantifiers. These constraints have demonstrated that quantifiers rest on number and number sense. In the first part of the paper, we turn to developing this argument. In the remainder, we report on work in neurobiology that test the empirical claims of the theory. In particular, we look at fMRI experiments and behavioral experiments with various patient populations that support the intimate connection between natural language quantification and number sense.
Which Way Is That System Going? The Gibbs Free Energy

So far we have treated the first and second laws separately, but in a real system both energy conservation and entropy play a role. The role of entropy in determining the spontaneous direction of a system was derived for an isolated system that exchanged neither energy nor material with its surroundings. There are few biological systems of interest that fulfill the requirements of this isolation. We need a state variable that will indicate the direction and equilibrium position of a system that undergoes radical changes in energy (usually measured as enthalpy) and entropy together. This state function exists. It is the Gibbs free energy, G.
On the Occurrence of Polymorphic Human Prothrombin ELECTROPHORETIC AND CHROMATOGRAPHIC ALTERATIONS OF THE MOLECULE DUE TO THE ACTION OF THROMBIN

This study was carried out to determine if previous reports by others concerning the polymorphic nature of prothrombin could be substantiated. The results obtained suggest that preparations of this important blood coagulation zymogen may undergo spontaneous activation with conversion to a very small but significant amount of thrombin. The active enzyme is then capable of producing cleavage at various points on the prothrombin molecule, which results in a heterogeneous mixture of molecules with different chromatographic and electrophoretic properties. Some of these molecules retain prothrombin activity. It seems probable that these events are responsible for the polymorphic nature of prothrombin previously reported, and they may also be indirectly responsible for the deleterious effects that certain cellulose and polymethacrylate ion exchange columns have been reported to produce during chromatography of the zymogen. A relatively homogeneous prothrombin preparation has been obtained by chromatography of less pure products on diethylaminoethyl cellulose columns at pH 7.4 with the use of a continuous buffer gradient. The zymogen thus isolated readily converts to thrombin in 25% (w/v) sodium citrate solution. However, if the preparations are altered owing to partial activation, this does not occur as readily but requires many days for the maximum yield of thrombin to be attained. Polyacrylamide disc electrophoresis, column chromatography, and gel filtration analysis have permitted the identification and isolation of at least seven activation fragments present in the prothrombin conversion system. They appear qualitatively and, in some respects, quantitatively in relation to the thrombin activity developed. These are compared to previous studies of the sedimentation and enzymatic properties of the prothrombin-thrombin system.
Rookie or Rock Star? Newspaper Coverage of Sarah Palin's Vice Presidential Campaign

The press had great potential to influence voter perceptions of vice presidential nominee Sarah Palin, given her relative obscurity as Governor of Alaska when she was picked as Republican John McCain’s running mate. This paper examines the press’ portrayal of Palin and the degree to which it influenced public affect toward her. A total of 2,592 individual news articles and editorials were content coded from 17 leading U.S. newspapers from late August 2008 through Election Day. The findings suggest that voters were presented with a highly visible, negative image of Palin that emphasized her “rookie” over her “rock star” status and that the tone of her coverage varied based on key factors. Palin’s coverage was more positive when the lead author was a woman and when Palin’s gender was mentioned. Local reporters were also more positive than reporters working for elite newspapers and national wire services. Our multivariate models of favorability toward Palin suggest that press coverage influenced public perceptions of Palin, especially among independents.
Pearls & Oy-sters: An isolated cranial nerve 6 palsy as a presentation of polycythemia vera

Polycythemia vera (PV) is a myeloproliferative disorder that can manifest neurologically with symptoms such as cerebrovascular events and cranial neuropathies involving cranial nerves 3, 4, and 6.
Vitamin D favorably alters the cancer promoting prostaglandin cascade.

Background: Preclinical studies suggest that 1,25- dihydroxyvitamin D (1,25(OH) 2 D) and celecoxib inhibit prostaglandins (PGs) associated with cancer through different mechanisms. We determined if there was synergy in their use. Patients and Methods: A total of 36 healthy women received daily for one month/menstrual cycle: placebo, 400 international units (IU) vitamin D-3, 2,000 IU vitamin D-3, or 2,000 IU vitamin D-3 plus 400 mg celecoxib. Serum and nipple aspirate fluid (NAF) were analyzed for PGE 2 and transforming growth factor (TGF)β1 and -2; serum for 25(OH)D (total, -D-2, -D-3), plasma for celecoxib; and mammary duct RNA for cyclooxygenase (COX)2. Results: 25(OH)D-3 increased (p<0.01) only in the groups receiving 2,000 IU vitamin D-3. PGE 2 decreased in the breast (p=0.01) only after receiving 2,000 IU vitamin D-3; 2,000 IU vitamin D-3 alone was more effective in decreasing PGE 2 than 2,000 IU vitamin D-3 plus celecoxib (p=0.018). COX2 expression decreased only in the breasts of women taking 2,000 IU vitamin D-3. Change in circulating 25(OH)D-3 correlated with change in TGFβ2 in the breast. Conclusion: Vitamin D- 3 reduces the PG cascade and increases TGFβ2 in a dose- dependent fashion. Adding celecoxib did not provide synergy. There is growing interest among women in bioactive food components as part of a healthy lifestyle. Dietary vitamin D reduces breast cancer (BCa) risk by controlling cell growth, and doses up to 2,000 IU/day can be taken long-term without toxicity. The odds of developing BCa among women with vitamin D levels above 42 ng/ml, requiring a dose of approximately 2,000 IU/day, was 50% less than in women with vitamin D levels of 0-11 ng/ml (1). Preclinical (2) and epidemiological (3) studies suggest that the anti-
Some Generalized BRS Transformations.I The Pure Yang-Mills Case

Some generalized BRS transformations are developed for the pure Yang-Mills theory, and a form of quantum gravity. Unlike the usual BRS transformations: these are nonlocal; may be infinite formal power series in the gauge fields; and do not leave the action invariant, but only the product exp(-S) with the Jacobian. Similar constructions should exist for many other field theory situations.
Purification and Properties of a Hydrogenase from Desulfovibrio vulgaris

Abstract The soluble hydrogenase of Desulfovibrio vulgaris was purified and some of its properties are described. The molecular weight was determined for the enzyme by sedimentation equilibrium (45,400) and amino acid analysis (44,800). The hydrogenase appears to be a loosely coiled molecule or to have a high axial ratio, which is reflected in an unusually low sedimentation coefficient (2.58S) and a low diffusion coefficient (D 5.85). The molecular weight of the hydrogenase (41,000), as calculated by the Svedberg equation, was in general agreement with the sedimentation equilibrium molecular weight. Amino acid analysis revealed the presence of six halfcystine residues per mole of enzyme and a total of 417 amino acid residues. The specificity of the hydrogenase and its capacity to reduce certain low potential dyes and cytochrome c3 was studied. Metal analysis of the hydrogenase indicated the presence of 1 mole of ferrous iron per mole of enzyme.
Covalent Nucleophilic Catalysis

Covalent nucleophilic catalysis is the involvement of a nucleophile on an enzyme (usually one of the side-chain groups of an α-amino acid residue) in forming a covalent (shared) bond with a reactant to generate an intermediate on the reaction pathway leading to the observed product(s). Keywords: nucleophilic catalysis; covalent intermediate
48. Age, Sex, Ethanol Levels, and Helmet Use Among Injured Motorcyclists

Introduction : Previous studies of motorcycle injuries show that helmet use is associated with a decrease in head trauma. Understanding patterns of helmet use is important in selecting and assessing injury prevention strategies. Methods : All 470 motorcyclists presenting to either of two regional Level I trauma centers from 7/93 through 12/95 comprise this case series. Thirty-three patients were excluded due to unknown helmet use or outcome, and 50 due to age under 18 years (for whom helmet use was required by state law). Results : Of 386 patients, 42% wore helmets, and 58% did not, with no difference in the mean ages of the groups. 13% of patients were women (n = 50), and 10% were passengers (n = 38). Women were 25 times more likely than men to be passengers (95% CI: 11 to 50), and passengers were 5 times more likely than drivers to not wear a helmet (95% CI: 2 to 16). Helmet use was not related to sex, even when the data were controlled for driver vs. passenger. Of 265 patients assayed for ethanol, 30% had >100 mg/dL, 7% had p 100 mg/dL), compared to 11% of helmeted ones.
White matter microstructure in untreated first episode bipolar disorder with psychosis: Comparison with schizophrenia

Lu LH, Zhou XJ, Keedy SK, Reilly JL, Sweeney JA. White matter microstructure in untreated first episode bipolar disorder with psychosis: comparison with schizophrenia. Bipolar Disord 2011: 13: 604–613. © 2011 The Authors. Journal compilation © 2011 John Wiley & Sons A/S. Objectives: White matter abnormalities have been reported in bipolar disorder. The present study aimed to investigate white matter integrity in untreated first episode patients with psychotic bipolar disorder using diffusion tensor imaging, and to compare observations with those from untreated first episode schizophrenia patients. Methods: Fractional anisotropy and mean diffusivity were measured in first episode psychotic patients with bipolar disorder (n = 13) or schizophrenia (n = 21) and healthy individuals (n = 18). Group differences were evaluated using voxel-based morphometry. Axial and radial diffusivity were examined in regions with altered fractional anisotropy in post-hoc analyses. Results: Patients with bipolar disorder showed lower fractional anisotropy than healthy controls in several white matter tracts. Compared with schizophrenia patients, bipolar disorder patients showed lower fractional anisotropy in the cingulum, internal capsule, posterior corpus callosum, tapetum, and occipital white matter including posterior thalamic radiation and inferior longitudinal fasciculus/inferior fronto-occipital fasciculus. Lower fractional anisotropy in bipolar disorder was characterized by increased radial diffusion rather than axial diffusion along the orientation of fiber tracts. Across several white matter tracts, both patient groups showed greater mean diffusivity than healthy individuals. Conclusions: Selectively increased radial diffusivity in bipolar disorder patients suggests structural disorganization in fiber tract coherence of neurodevelopmental origin or alterations in myelin sheaths along fiber tracts. In contrast, increased isotropic diffusion along white matter tracts in schizophrenia patients with alterations in both radial and axial diffusivity suggests increased water content outside the axonal space. Thus, the present results suggest that different pathophysiological mechanisms may underlie white matter microstructural abnormalities in bipolar disorder and schizophrenia.
Boron Carbide, a New Substrate for Fuel Cell Electrocatalysts

A NUMBER of investigators have reported high-performance, direct hydrocarbon fuel cells1–4. In every case, the direct hydrocarbon anode has used a large amount of high-area platinum black or Raney platinum in the range of about 10–100 mg/cm2 of geometric electrode area. This tends to counteract the advantage of being able to operate on inexpensive hydrocarbon fuels. Furthermore, there is a tendency for performance to be proportional to platinum content. Niedrach5 has shown that ‘Teflon’-bonded electrodes6 containing mechanical mixtures of platinum black with tantalum or platinum deposited on tantalum give performance on propane which is just proportional to the platinum content. Thus, the advantage of reduction in platinum content is cancelled out by the reduction in performance.
On the effectiveness of cellular automata to add real numbers

This paper investigates the effectiveness of cellular automata to compute arithmetic functions over the set of real numbers. Since cellular automata (CA) have parallel computational ability in conjunction with the capacity to accept an infinite length input, the CA should be able to effectively compute real number arithmetic. This paper shows that typical representations of real numbers do not lend themselves to effective computation by a CA and that a nonstandard representation must be employed in order to accomplish this.
A study of visual and tactile terrain classification and classifier fusion for planetary exploration rovers

Knowledge of the physical properties of terrain surrounding a planetary exploration rover can be used to allow a rover system to fully exploit its mobility capabilities. Terrain classification methods provide semantic descriptions of the physical nature of a given terrain region. These descriptions can be associated with nominal numerical physical parameters, and/or nominal traversability estimates, to improve mobility prediction accuracy. Here we study the performance of multisensor classification methods in the context of Mars surface exploration. The performance of two classification algorithms for color, texture, and range features are presented based on maximum likelihood estimation and support vector machines. In addition, a classification method based on vibration features derived from rover wheel–terrain interaction is briefly described. Two techniques for merging the results of these “low-level” classifiers are presented that rely on Bayesian fusion and meta-classifier fusion. The performance of these algorithms is studied using images from NASA's Mars Exploration Rover mission and through experiments on a four-wheeled test-bed rover operating in Mars-analog terrain. Also a novel approach to terrain sensing based on fused tactile and visual features is presented. It is shown that accurate terrain classification can be achieved via classifier fusion from visual and tactile features.
A note on the use of direct sufficient conditions in optimal control problems

It is always possible to transform a nonautonomous optimal control problem into an autonomous one. However, the direct sufficient conditions may yield no information when applied to this autonomous problem, even though they do allow one to conclude sufficiency when applied to the original nonautonomous problem.
Some promising insecticidal plants

In addition to tobacco, pyrethrum and the rotenonebearing plants of the genera Derris and Lonchocarpus, seventeen of which are discussed in this paper, have been found promising as sources of insecticides.
Server Scheduling to Balance Priorities, Fairness, and Average Quality of Service

Often server systems do not implement the best known algorithms for optimizing average Quality of Service (QoS) out of concern that these algorithms may be insufficiently fair to individual jobs. The standard method for balancing average QoS and fairness is to optimize the $\ell_p$ norm, $1<p<\infty$. Thus we consider server scheduling strategies to optimize the $\ell_p$ norms of the standard QoS measures, flow and stretch. We first show that there is no $n^{o(1)}$-competitive online algorithm for the $\ell_p$ norms of either flow or stretch. We then show that the standard clairvoyant algorithms for optimizing average QoS, Shortest Job First (SJF), and Shortest Remaining Processing Time (SRPT), are scalable for the $\ell_p$ norms of flow and stretch. We then show that the standard nonclairvoyant algorithm for optimizing average QoS, Shortest Elapsed Time First (SETF), is also scalable for the $\ell_p$ norms of flow. We then show that the online algorithm, Highest Density First (HDF), and the nonclairvoyant algorithm, Weighted Shortest Elapsed Time First (WSETF), are scalable for the weighted $\ell_p$ norms of flow. These results suggest that the concern that these standard algorithms may unnecessarily starve jobs is unfounded. In contrast, we show that the Round Robin, or Processor Sharing, algorithm, which is sometimes adopted because of its seeming fairness properties, is not $O(1+\epsilon)$-speed, $n^{o(1)}$-competitive for sufficiently small $\epsilon$.
Epigenetics and the control of epithelial sodium channel expression in collecting duct

In eukaryotic nuclei, genomic DNA is compacted with histone and nonhistone proteins into a dynamic polymer termed chromatin. Reorganization of chromatin structure through histone modifications, the action of chromatin factors, or DNA methylation, can profoundly change gene expression. These epigenetic modifications allow heritable and potentially reversible changes in gene functioning to occur without altering the DNA sequence, thus extending the information potential of the genetic code. This review provides an introduction to epigenetic concepts for renal investigators and an overview of our work detailing an epigenetic pathway for aldosterone signaling and the control of epithelial Na + channel- α ( ENaCα ) subunit gene expression in the collecting duct. This new pathway involves a nuclear repressor complex, consisting of histone H3 Lys-79 methyltransferase disruptor of telomeric silencing-1a (Dot1a), ALL1 fused gene from chromosome 9 (Af9), a sequence-specific DNA-binding protein that binds the ENaCα promoter, and potentially other nuclear proteins. This complex regulates targeted histone H3 Lys-79 methylation of chromatin associated with the ENaCα promoter, thereby suppressing its transcriptional activity. Aldosterone disrupts the Dot1a–Af9 interaction by serum- and glucocorticoid-induced kinase-1 phosphorylation of Af9, and inhibits Dot1a and Af9 expression, resulting in histone H3 Lys-79 hypomethylation at specific subregions, and derepression of the ENaCα promoter. The Dot1a–Af9 pathway may also be involved in the control of genes implicated in renal fibrosis and hypertension.
Green synthesis of graphene sand composite (GSC) as novel adsorbent for efficient removal of Cr (VI) ions from aqueous solution

Abstract Cr (VI) is one of the most toxic contaminants recognized as a carcinogenic and mutagenic agent and needs complete removal from wastewater before disposal. In the present study, a novel graphene based adsorbent was synthesized from sugar and sand using green chemistry approach and adsorption of Cr (VI) ions from aqueous solution was studied by batch adsorption technique under varying experimental conditions like contact time, pH, adsorbent dose, initial Cr (VI) concentration and temperature. The characterization of the prepared graphene sand composite (GSC) was accomplished by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), X-ray diffraction(XRD) analysis, Raman spectroscopy, electron diffraction measurements, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy (EDX) and surface area measurements. The specific surface area of the GSC before and after activation was determined to be 100 m 2 /g and 157 m 2 /g, respectively. The optimum adsorption of Cr (VI) by the new adsorbent, coined as GSC, was observed at pH 1.5 The maximum adsorption capacity of GSC for Cr (VI) was found to be 2859.38 mg/g at room temperature which is claimed to be one of the exceptionally high values reported so far in the literature. The equilibrium sorption data were fitted satisfactorily to the Langmuir adsorption model with R 2 value of 0.99108. The progress of the adsorption process was found to follow the second order kinetics. The results obtained in this study illustrated that the prepared graphenic material could be an effective and economically viable adsorbent for removal of Cr (VI) ions.
Experimental species removal alters ecological dynamics in a natural ecosystem

Theory predicts that species extinction or invasion can affect the temporal dynamics of ecological communities by altering feedback patterns and by damping or amplifying environmental variation via changes in the network of species interactions, but because of the logistical challenges of investigating temporal dynamics, evidence from natural ecosystems is lacking. In a long-term experimental manipulation of a rocky intertidal community on Tatoosh Island, Washington, USA, chronic removal of the dominant species Mytilus californianus altered the dynamics of the system, causing reductions in the temporal variability of three subdominant species but no consistent change in the spectral characteristics or the order of density dependence across experimental replicates. This pattern of results suggests that Mytilus californianus impacted the temporal dynamics by amplifying environmental stochasticity, rather than by changing feedback pathways as is emphasized in most theoretical predictions and laboratory studies. Hence, further investigation of the mechanisms and implications of transmission of environmental stochasticity in natural ecosystems is merited.
Fracture patterns among the Nubians of Semna South, Sudanese Nubia

A collection of 592 individuals from the site of Semna South in Sudanese Nubia was studied for evidence of healed fractures of the skull and appendicular skeleton. The sample included 241 males, 239 females, 109 subadults and three adults for whom a sex could not be determined. Potential analytical and interpretive bias due to vagaries of preservation was quantified and examined. Almost 21% of the adults exhibited at least one healed fracture, while only two subadults showed such trauma. Rates of fractures, calculated for each bone, varied from a high of 17.9% for the cranium to a low of 0% for the right femur. Some fractures were likely caused by the physical environment, for example, falls along the rocky shores of the Nile. Other trauma, such as craniofacial fractures, found in both males and females, may have been due to interpersonal violence. The high rate of craniofacial trauma may indicate that this group experienced social stress which could have precipitated or intensified interpersonal violence. Copyright © 1999 John Wiley & Sons, Ltd.
Catalytic hydrodechlorination of chlorinated ethenes by nanoscale zero-valent iron

Abstract The reduction of six chlorinated ethenes by nanoscale iron ( dichloroethenes (DCEs) > trichloroethene (TCE) > tetrachloroethene (PCE)). This trend suggests the reduction of chlorinated ethenes by nanoscale iron did not occur under thermodynamic control (e.g. reduction potential), rather, it proceeded via a catalytic pathway involving reactive hydrogen species. The reduction of TCE under five different conditions of initial dissolved hydrogen concentrations which varied from about 0.02 to 1.2 mM confirmed the importance of hydrogen in the reaction pathway and revealed an excellent linear correlation between rate constant and hydrogen concentration. Reduction of a chlorinated ethane (1,1,1,2-tetrachloroethane) which produced 1,1-DCE as an intermediate, showed no dependence on hydrogen concentrations but the disappearance of the ethene intermediate did. TCE reduction by commercial grade micro-sized iron samples, in contrast, showed insignificant dependence on hydrogen concentration, suggesting the nanoscale iron synthesized by borohydride reduction of iron salts is particularly suited for hydrogen utilization through a catalytic reduction of chlorinated ethenes.
The effect of the suspensor and gibberellic acid on Phaseolus vulgaris embryo protein content.

Abstract The role of the suspensor in the early development of the dicot embryo has not yet been defined. It has been described as merely an anchor and also as the major route of nutrients into the embryo. In order to further elucidate the role of the suspensor, early 0.2-mm and late heart stage 0.5-mm Phaseolus vulgaris (var. Taylor's Horticultural) embryos have been examined in tissue culture. It is known that Phaseolus embryos in culture at low osmotic potential will germinate precociously and that embryos in culture at high osmotic potential will either fail to grow or form callus. Optimum sucrose concentrations for continued, normal embryonic development of 0.2 mm and 0.5 mm P. vulgaris in tissue culture with Gamborg B5 medium were determined to be 12 and 6%, respectively. Protein content was examined in embryos and suspensors. Results showed that both 0.2- and 0.5-mm embryos required an attached suspensor for maximum protein content. Protein levels were substantially decreased when the embryo was cultured detached from or without the suspensor. Gibberellic acid at 10 −6 to 10 −7 , M restored the protein content to that of freshly excised embryos.
Energy Transport in Jammed Sphere Packings

We calculate the normal modes of vibration in jammed sphere packings to obtain the energy diffusivity, a spectral measure of transport. At the boson peak frequency, we find an Ioffe-Regel crossover from a diffusivity that drops rapidly with frequency to one that is nearly frequency independent. This crossover frequency shifts to zero as the system is decompressed towards the jamming transition, providing unambiguous evidence of a regime in frequency of nearly constant diffusivity. Such a regime, postulated to exist in glasses to explain the temperature dependence of the thermal conductivity, therefore appears to arise from properties of the jamming transition.
A self-organization based optical flow estimator with GPU implementation

This work describes a parallelizable optical flow field estimator based upon a modified batch version of the Self-Organizing Map (SOM). This estimator handles the ill-posedness in gradient-based motion estimation via a novel combination of regression and self-organization. The aperture problem is treated using an algebraic framework that partitions motion estimates obtained from regression into two sets: one (set Hc) containing motion estimates with high confidence and another (set Hp) with low confidence. The self-organization step uses a uniquely designed pair of sets: training set (Q = Hc) and the initial weights set (\({W=H_c \cup H_p}\)). It is shown that with this specific choice of training and initial weights sets, the interpolation of flow vectors is achieved primarily due to the regularization property of the SOM. Moreover, the computationally involved step of finding the winner unit in SOM simplifies to indexing into a 2D array making the algorithm highly scalable. To preserve flow discontinuities at occlusion boundaries, we have designed an anisotropic neighborhood function for SOM that uses a novel optical flow constraint equation residual-based distance measure. A multi-resolution or pyramidal approach is used to estimate large motion. As self-organization based motion estimation is computationally intense, parallel processing on graphics processing units is used for speedup. As the algorithm is data (rather datum) parallel, with sufficient number of computing cores, the implementation of the estimator can be made real time. With the available ground truth from Middlebury database, error metrics like average angular error and average end point error are computed and are shown to be comparable with other leading techniques.
Weak associations between prognostic biomarkers and disease in preliminary studies illustrates the breach between statistical significance and diagnostic discrimination

Abstract Introduction Prior to actual well-designed outcome studies, statistical significance does not imply diagnostic usefulness. Sensitivity/specificity graphs have been a mainstay in evaluating potential diagnostic usefulness. Unfortunately, many recent studies have been expressed as relative risk (RR) or odds ratios (OR) based on statistical significance that produces misleading constructs, especially when the relationship between the biomarker and disease is weak. The purpose of this review is to discuss the meaning of the diagnostic relationships when the association between a biomarker and a disease is weak such that it shows poor discrimination by sensitivity/specificity plots. Methods Review of the literature, illustrative example and calculation of positive predictive values. Results Information from the literature showing the equivalency between OR and sensitivity/specificity plots and defining weak diagnostic discrimination. Demonstration of how confounders can alter between study statistical significance when there is a weak diagnostic relationship. Conclusions RR or OR should be expressed as diagnostic sensitivity/specificity plots. Usually predictive values will identify whether or not there is potential diagnostic value that is economically reasonable. Very weak diagnostic relationships produce very low positive predictive values. Great caution should be exercised when considering weak associations for diagnostic use, especially if the biomarker is not a modifiable risk factor.
Examining relationships among family influence, family culture, flexible planning systems, innovativeness and firm performance

Abstract The purpose of this article is to draw on the resource-based view of the firm and the upper echelons theoretical perspective to position family influence, family business culture and flexible planning systems as drivers of firm innovativeness, and subsequently firm performance. We establish these relationships using SEM statistical techniques to analyze responses of small- to medium-sized family businesses using established survey instruments. We find evidence that family influence positively influences family culture, that family culture improves the ability of families to be strategically flexible and that this flexibility positively impacts firm innovativeness, subsequently benefitting firm performance. The implications for practitioners are discussed.
Optimal government finance policy and exchange rate management in a stochastically growing open economy

Abstract Optimal monetary policy is analyzed in a stochastic small open economy, consisting of risk averse representative agents. The analysis shows how optimal monetary policy should be directed toward an optimal interest rate target. This target, which maximizes the intertemporal utility of the representative agent, is determined by balancing off the marginal gains of a higher interest rate on increased growth and the future consumption it generates, against the marginal losses stemming from a reduction in the holdings of real money balances. The paper shows how an appropriately set monetary growth rate eliminates the need for continuous intervention in the exchange market.
Identification of an anteriorly displaced meniscus in vitro by means of three-dimensional image reconstructions

Computerized tomography has some limitations for diagnosis of internal derangements of the TMJ. The use of three-dimensional image reconstructions of CT data may enhance the diagnostic utility of CT. In a cadaver simulation, three-dimensional imaging was able to demonstrate the location of a displaced meniscus which was not obvious in two-dimensional sections. Location of the meniscus was aided by the use of a "transparency mode" in displaying the data.
Equilibrium and kinetic aspects of soddyite dissolution and secondary phase precipitation in aqueous suspension

The dissolution and transformation of soddyite ([UO2]2SiO4·2H2O) have been examined in aqueous suspension at pH 6 and 0.01 M NaNO3. Soddyite is an important component of the paragenetic sequence of secondary minerals that arises from the weathering of uraninite ore deposits and corrosion of spent nuclear fuel. A soddyite of high purity and crystallinity was synthesized in the laboratory for use in dissolution experiments. In batch experiments, rapid dissolution occurred over an initial period of several hours followed by continuing steady-state dissolution for up to 700 h. Up to 200 h. U and Si were released into solution at their stoichiometric 2:1 ratio in soddyite. A decrease in the dissolved U concentration was observed at longer times, indicating the precipitation of a new phase. Even after precipitation of the secondary phase, the continuing dissolution of soddyite could be inferred from increasing dissolved Si concentrations. Through the use of X-ray diffraction, Raman spectroscopy, and scanning electron microscopy, the precipitated phase was identified as a clarkeite-like sodium uranyl oxide hydrate. The sodium uranyl oxide hydrate was ultimately the solubility-controlling solid, despite being only a minor component. Soddyite dissolution rates were quantified in flow-through experiments, in which reaction products were flushed from the reactors, thereby avoiding reprecipitation of U. The measured dissolution rate at pH 6 was 0.71 μmol U m-2 h-1. A slower dissolution rate of 0.44 μmol U m-2 h-1 was observed when 100 μM dissolved Si was added to the reactor influent. Copyright © 2002 Elsevier Science Ltd.
Binary trees as a computational framework

We present a new set of algorithms for performing arithmetic computations on the set of natural numbers, represented as ordered rooted binary trees. We show formally that these algorithms are correct and discuss their time and space complexity in comparison to traditional arithmetic operations on bitstrings.Our binary tree algorithms follow the structure of a simple type language, similar to that of Godel's System T.Generic implementations using Haskell's type class mechanism are shared between instances shown to be isomorphic to the set of natural numbers. This representation independence is illustrated by instantiating our computational framework to the language of balanced parenthesis languages.The self-contained source code of the paper is available at http://logic.cse.unt.edu/tarau/research/2012/jtypes.hs. HighlightsWe present a new set of algorithms for performing arithmetic computations using binary trees.Our arithmetic algorithms have average time and space complexity comparable to traditional operations on bitstrings.Our results are implemented using Haskell instances isomorphic to natural numbers.
An efficient discriminant-based solution for small sample size problem

Classification of high-dimensional statistical data is usually not amenable to standard pattern recognition techniques because of an underlying small sample size problem. To address the problem of high-dimensional data classification in the face of a limited number of samples, a novel principal component analysis (PCA) based feature extraction/classification scheme is proposed. The proposed method yields a piecewise linear feature subspace and is particularly well-suited to difficult recognition problems where achievable classification rates are intrinsically low. Such problems are often encountered in cases where classes are highly overlapped, or in cases where a prominent curvature in data renders a projection onto a single linear subspace inadequate. The proposed feature extraction/classification method uses class-dependent PCA in conjunction with linear discriminant feature extraction and performs well on a variety of real-world datasets, ranging from digit recognition to classification of high-dimensional bioinformatics and brain imaging data.
Quantitative multiple opening-and-closing plankton samplers

Abstract Two quantitative plankton samplers, incorporating identical opening-and-closing principles, have been constructed for serial sampling of zoo-plankton in the upper 1000 m of water. The multiple Plankton Sampler (MPS) is designed to low at three depth ranges (0–100 m; 100–250 m; and 250–500 m) in the upper 500 meters, while the Bathypelagic Sample (BPS) is intended for simulataneous hauling in the more sparsely populated 500–1000 m depths. Employment of a pressure-sensitive release mechanism allows horizontal or oblique towing in preselected depth intervals—thus abolishing the need for messengers. The sampler designs are flexible and may be modified with respect the size of frame opening number of nets and depth ranges to be sampled.
Positive and negative deflection-angle Coulomb scattering

Abstract The decomposition of the Rutherford amplitude into positive and negative deflection-angle contributions shows how Fraunhofer diffraction for charged-particle scattering is moved away from forward angles.
Saving the invisible axion

Abstract Recently it has been shown that the energy density contributed today by coherent oscillations of the invisible axion field corresponds to Ω ⋍ 0.1 ( ƒ a 10 12 GeV ) 11 9 ( ƒ a is the scale of peccei-Quinn SSB), apparently ruling out ƒ a ≳ O(10 13 GeV ) . We propose a simple way to avoid this bound: entropy production when the temperature of the universe is between about 1 GeV and 1 MeV. The entropy might be produced by a first-order phase transition, or the out-of-equilibrium decays of a relic particle species. For ƒ a ⋍ 10 15 GeV , the entropy of the universe must be increased by a factor of O(102−103) to have Ω a ⋍ O (1) . If inflation also occurs at a temperature ⋍1015 GeV, then the de Sitter space produced fluctuations in the axion field lead to a Zel'dovich-like spectrum of (isothermal) perturbations in the axion energy density, with amplitude about 10−4. It has recently been argued that in an axion-dominated universe such a spectrum could lead to the formation of of the structure observed in the universe today.
Effect of Binocular Magnification Devices on Stereoscopic Depth Resolution

An observer’s just discriminable difference in depth is a function of his interocular distance, his threshold difference in binocular parallax, and the observation distance. Magnification devices consisting of lenses and/or prisms will change the threshold of depth resolution because the latter now depends on the optical properties of the device as well as on the observer’s characteristics. An equation has been derived expressing this change in linear threshold of depth resolution as a function of the lens and prism power of the device, the separation of the components of the device from the eye, the observer’s interocular distance, and the object distance. Free choice of the optical properties of such magnifiers is, however, restricted since these properties must permit a clear retinal image of the object to be formed simultaneously on the foveas of both of the observer’s eyes. In general, plus lenses and base-in prisms will enhance the depth resolution and this points to the use of such devices in tasks demanding high depth resolution at close observation distances, as, for example, in surgery or inspection of surface defects.An experimental determination of the change in linear depth resolution produced by a binocular magnifier showed close agreement with the theoretical prediction.
Effects of estrogen on bone mRNA levels of sclerostin and other genes relevant to bone metabolism in postmenopausal women

Context: Studies in postmenopausal women have shown that estrogen reduces circulating sclerostin levels, but effects of estrogen on skeletal sclerostin mRNA levels are unknown. Objective: The objective of the study was to evaluate the effects of short-term estrogen treatment on bone mRNA levels of sclerostin and other genes relevant to bone metabolism. Design, Setting, and Patients: Needle bone biopsies were obtained from 20 postmenopausal women treated with transdermal estrogen for 3 weeks and 20 untreated controls. Quantitative PCR analyses were used to examine the expression of sclerostin and other genes related to bone metabolism, including 71 additional genes linked to bone density/fracture from genome-wide association studies. Results: Estrogen treatment was associated with lower bone sclerostin mRNA levels (by 48%, P < .05) and with lower (by 54%, P < .01) mRNA levels of the sclerostin-related protein, sclerostin domain-containing protein 1 (SOSTDC1), which is also a Wnt/bone morphogenetic protein ...
Influence of Cluster Exposure to Sun on Fruit Composition of ‘Norton’ Grapes (Vitis estivalis Michx) in Missouri

The influence of cluster exposure to sunlight on fruit composition of ‘Norton’ grapes was studied. Three exposure levels, such as fully exposed, partly exposed, and fully shaded, were established by canopy management practices, such as shoot positioning, shoot thinning, and leaf removal. Row orientation significantly impacted fruit composition with east west orientation and resulted in high total soluble solids, anthocyanin, and tannin content. Titratable acidity, total phenol, and juice potassium was highest in vines planted in north south row orientation. Fully shaded clusters had the lowest total soluble solids, lower glucose and fructose content, and highest juice potassium and malic acid content. Fully exposed clusters displayed lowest titratable acidity. Fully exposed clusters on the west and south side of the canopy received photosynthetically active radiation of more than 1,100 μ mole m-2 sec-1, while partly exposed and fully shaded clusters received less than 10% of total photosynthetically activ...
Quantitative extraction of methylmalonic and succinic acids and their determination by gas-liquid chromatography.

Abstract A method for routine small-volume solvent extraction, derivitization and gas-liquid chromatographic analysis of methylmalonic and succinic acids is described. The procedure allows for quantitative determination of mass and radioactivity of these acids and can be applied to metabolic studies of the genetic disorder methylmalonylacidurea.
NMR studies of p-substituted pyridine derivatives oriented in lyotropic mesophases

Abstract High resolution nuclear magnetic resonance spectra have been obtained for seven p-subetituted pyridine derivatives oriented in lyotropic mesophases derived from sodium decyl sulfate and potassium laurate. Spectral analyses yielded indirect as well as direct coupling information for the ring protons of the pyridine system. The structural parameters determined for all molecules show good agreement with microwave data for pyridine. Orientational changes throughout the series are attributed to solute-solvent interactions.
Prolonged Blinking with TERS Probes

Tip-enhanced Raman spectroscopy (TERS), an emerging technique combining scanning probe microscopy (SPM) and Raman spectroscopy, provides the sensitivity and selectivity necessary for chemical imaging with nanoscale resolution. We demonstrate that coating the fragile plasmonic structures used to enhance the electric field with a protective layer improves significantly its mechanical, chemical, and thermal stability without loss of the extreme optical enhancement that appears as a blinking phenomenon. This observation provides important information on the mechanism of blinking. The fact that TERS blinking from a polymer layer is preserved when the analyte is separated from the plasmonic nanostructure by a 3 nm thick coating proves that chemical enhancement and charge transfer do not play a significant role in the blinking. Rather, thermally activated diffusion appears to be the dominant mechanism. While extreme enhancement persists only for minutes for an unprotected silver-coated tip, it persists for tens of hours with plasmonic structures coated by an ultrathin layer of alumina (Al2O3), opening broader opportunities for the study of blinking and for chemical imaging and sensing based on plasmonic structures.
DIFFERENTIAL LOCALIZATION OF CELL SURFACE AND SECRETORY COMPONENTS IN RAT INTESTINAL EPITHELIUM BY USE OF LECTINS

Sections through various levels of small intestine from adult male rats were examined by fluorescence microscopy after treatment with fluorescein isothiocyanate-labeled lectins from Dolichos biflorus, Lotus tetragonolobus, Ricinus communis, and Triticum vulgare (wheat germ). The latter three lectins reacted with the microvillar portion of the epithelial cells lining the crypts and villi in sections of intestine adjacent to the pylorus. This pattern of reactivity was sharply altered along the first 15 cm of intestine so that in sections distal to this point the luminal surfaces of only those epithelial cells in the crypts and at the base of the villi reacted with the L. tetragonolobus and R. communis lectins, whereas the wheat germ lectin reacted with the surfaces of the cells lining the villi. In sections from the distal end of the small intestine, all three lectins reacted with the surfaces of cells only at the base of the villi and in the crypts. These results show a difference in surface components in cells at various portions on the villi and the dependence of these differences on the region of intestine. The D. biflorus lectin reacted with approximately 25% of the goblet cells at each level of intestine studied whereas the reactivities of the goblet cells with the other three lectins were dependent upon the region of intestine.
Long-acting reversible contraceptive use among teens prevents unintended pregnancy: a look at the evidence

. Although failure rates with perfect use can be very low, contraceptive methods that require a woman to remember to take medications, return to a clinic for an injection or secure refills result in typical-use failure rates that are much higher. For example, failure rates for the commonly used oral contraceptive pill (OCP) and depomedroxy progesterone acetate injection increase from 1% when used perfectly to 6–9% in real-world use
On the determination and construction of A- and MV-optimal block designs for comparing a set of test treatments to a set of standard treatments

In this paper we consider experimental situations in which t test treatments are to be compared to s standard treatments in b blocks of size k. A design is said to be A-optimal in such situations if it minimizes the sum of the variances of the least-squares estimates for the elementary treatment contrasts between the test treatments and the standard treatments and a design is said to be MV-optimal if it minimizes the maximal variance of the same least squares estimates. A method is proposed for finding A- and MV-optimal designs in such situations and some sufficient conditions are given under which a design obtained using the proposed method will be A- and MV-optimal. Some examples are also given to show how the results obtained can be applied.