cssi/SciSciGPT-SciSciNet huggingface dataset:
Autotaxin Structure Activity Relationships Revealed through Lysophosphatidylcholine Analogs

Autotaxin (ATX) catalyzes the hydrolysis of lysophosphatidylcholine (LPC) to form the bioactive lipid lysophosphatidic acid (LPA). LPA stimulates cell proliferation, cell survival, and cell migration and is involved in obesity, rheumatoid arthritis, neuropathic pain, atherosclerosis and various cancers, suggesting that ATX inhibitors have broad therapeutic potential. Product feedback inhibition of ATX by LPA has stimulated structure-activity studies focused on LPA analogs. However, LPA displays mixed mode inhibition, indicating that it can bind to both the enzyme and the enzyme-substrate complex. This suggests that LPA may not interact solely with the catalytic site. In this report we have prepared LPC analogs to help map out substrate structure-activity relationships. The structural variances include length and unsaturation of the fatty tail, choline and polar linker presence, acyl versus ether linkage of the hydrocarbon chain, and methylene and nitrogen replacement of the choline oxygen. All LPC analogs were assayed in competition with the synthetic substrate, FS-3, to show the preference ATX has for each alteration. Choline presence and methylene replacement of the choline oxygen were detrimental to ATX recognition. These findings provide insights into the structure of the enzyme in the vicinity of the catalytic site as well as suggesting that ATX produces rate enhancement, at least in part, by substrate destabilization.
A conservative bound on the estimation error covariance matrix in the presence of correlated driving noise and correlated discrete measurement noise.

Abstract In an earlier paper, the conservative and minimal bound to the crosscorrelation terms between estimation error and a random forcing function was presented. That bound was found to be a particular linear combination of the estimation error covariance and the forcing function covariance involving a free scalar parameter. The bound was then substituted for the cross-correlation terms in the differential equation for the estimation error covariance matrix in order to approximate its behavior between discrete measurement times. The time history of the free parameter which minimized a linear combination of the elements of the estimated covariance matrix at the next measurement time was found as the noniterative solution to an optimal control problem with a matrix state. In this paper, necessary and sufficient conditions are presented for the problem of minimizing a linear combination of the elements of the approximated estimation error covariance at the end of an interval in which are linearly incorporated a finite number of discrete vector measurements corrupted by white and/or correlated measurement noise. Although the determination of the optimal trajectory in general requires iteration, a particularly simple algorithm is presented. Numerical results are presented for the case of a satellite in a highly elliptic orbit about a model Earth.
Differentiation of the Blastocyst of the rhesus monkey.

A method of flushing the oviduct and/or uterus of rhesus monkeys was used to obtain a number of preimplantation stages, of which four cleavage stages and seven blastocysts that were judged to be normal were studied cytologically using transmission electron microscopy. In addition to the usual changes in mitochondria and endoplasmic reticulum that accompany differentiation of the blastomeres, the blastocysts with zonae showed sequestration of areas of cytoplasm. The first indications of junctional complexes were short stretches of parallel membrane with a slightly increased density found in the morula stage. Blastocysts developed typical apical junctional complexes, but in addition showed extensive gap junctions linking trophoblast and inner cell mass, and epiblast and differentiating endoderm. Endodermal differentiation occurred at about the same time that a basal lamina was found under mural trophoblast and epiblast (but not polar trophoblast or endoderm). Enlarged torn zonae were found in association with one blastocyst and unaccompanied by blastocysts, including a case in which the animal subsequently proved to be pregnant. This observation suggests that hatching is a normal feature of zonal escape in this species. The trophoblast of blastocysts without zonae had well-formed apical absorptive areas and, in some instances, long irregular microvilli in the area near the inner cell mass. Cell debris, vacuoles containing debris and isolated cells, although variable, were common features of the preimplantation stage in the rhesus monkey.
Cyclotron-produced thulium-167 for bone and tumor scanning.

Abstract A method has been described for the cyclotron production of 9·6-day thulium-167. Ion exchange resin chromatography was used to separate the 167 Tm from the HoCl 3 target material. Distribution of the separated 167 Tm citrate in normal dogs and rats and in tumor-bearing mice has been determined. The results of these studies indicate that 167 Tm is potentially useful for tumor and bone scanning.
Ryk is expressed in a differentiation-specific manner in epithelial tissues and is strongly induced in decidualizing uterine stroma.

Ryk is expressed in a differentiation-specific manner in epithelial tissues and is strongly induced in decidualizing uterine stroma
Risk‐return measures of hedging effectiveness: The case of multiple cash and futures markets

In this article we consider the measure of hedging effectiveness proposed by Howard and D' Antonio (HD) when there are multiple cash and futures markets. It is found that the HD measure can be decomposed into two components: one solely determined by the futures market conditions, the other affected by both cash and futures markets as well as the hedger's cash portfolio. We then analyze the impacts of optimal cash portfolios on the HD measure. Although the Ederington hedging effectiveness is bounded over all cash portfolios, the conclusion does not apply to the HD measure.
The GGA proteins: key players in protein sorting at the trans-Golgi network

The GGA ( G olgi-localized, γ -ear containing, A DP-ribosylation factor binding) family of multidomain coat proteins was first described in the year 2000. They are now known to occupy a central position in the trafficking of the mannose 6-phosphate receptors and other cargo molecules from the trans-Golgi network to the endosome/lysosome system. This review covers the recent structural and cell biological studies that have provided mechanistic insights into the function of the GGAs in mannose 6-phosphate receptor trafficking.
Borderline Resectable Pancreatic Cancer: Definitions, Management, and Role of Preoperative Therapy

With recent advances in pancreatic imaging and surgical techniques, a distinct subset of pancreatic tumors is emerging that blurs the distinction between resectable and locally advanced disease: tumors of "borderline resectability." In our practice, patients with borderline-resectable pancreatic cancer include those whose tumors exhibit encasement of a short segment of the hepatic artery, without evidence of tumor extension to the celiac axis, that is amenable to resection and reconstruction; tumor abutment of the superior mesenteric artery involving <180 degrees of the circumference of the artery; or short-segment occlusion of the superior mesenteric vein, portal vein, or their confluence with a suitable option available for vascular reconstruction because the veins are normal above and below the area of tumor involvement. With currently available surgical techniques, patients with borderline-resectable pancreatic head cancer are at high risk for a margin-positive resection. Therefore, our approach to these patients is to use preoperative systemic therapy and local-regional chemoradiation to maximize the potential for an R0 resection and to avoid R2 resections. In our experience, patients with favorable responses to preoperative therapy (radiographical evidence of tumor regression and improvement in serum tumor marker levels) are the subset of patients who have the best chance for an R0 resection and a favorable long-term outcome.
TU‐A‐108‐01: Four‐Dimensional Monte Carlo Using the TOPAS TOol for PArticle Simulation

Purpose: As the number and diversity of 4D radiation therapy treatment modalities increases, with techniques from IMRT, VMAT, SBRT, IGRT and IMPT to proton and ion beam scanning, the value of a comprehensive 4D Monte Carlo dose calculation tool has become evident. In silico experiments provide a powerful platform to study sensitivity of dose calculation techniques to motion errors, beam instabilities and interplay effects. We present a comprehensive system to meet this growing need. Methods: We have provided rich 4D capabilities within the TOPAS TOol for PArticle Simulation. TOPAS allows any one or more simulation parameter to vary over time, such as a beam current, the geometrical position of a treatment head component, a magnetic field, a 4D CT time slice or a gating signal for scoring. In use at 25 research institutions, TOPAS has been brought to bear on a wide range of 4D problems. We present 4D capabilities, including modulator wheel rotation during beam current modulation, beam scanning, MLC leaf motion, gantry rotation and 4D CT. Results: It is imperative that 4D simulation tools provide 4D‐scoring capabilities, such as scorers that can be gated by time, or phase space output that can associate time to each saved particle. Only with such tools can one confirm that the simulation is accurate in not just three dimensions but four. We show such results that confirm TOPAS 4D performance, both as time‐sliced histograms and through simulated 4D radiography (simulated films darkening as dose accumulates over time). Conclusion: TOPAS has proven to be a comprehensive 4D simulation tool. While current users are mainly in proton therapy, TOPAS is being extended for use in ion, x‐ray, electron and brachytherapy. While there are many excellent MC tools already for some of these modalities, TOPAS is unique in the 4D domain.
Developing and Validating a Reliable TPACK Instrument for Secondary Mathematics Preservice Teachers

AbstractWithin the realm of teaching middle and high school mathematics, the ability to teach mathematics effectively using various forms of technology is now more important than ever, as expressed by the recent development of the Common Core State Standards for Mathematical Practice. This article presents the development process and the results from 15 institutions and more than 300 surveys completed by secondary mathematics preservice teachers. The results suggest that technological, pedagogical, and content knowledge; technology knowledge; content knowledge; and pedagogical knowledge constructs are valid and reliable, whereas pedagogical content knowledge, technological content knowledge, and technological pedagogical knowledge domains remain difficult for preservice teachers to separate and self-report.
Consideration of the oasis analogy for chemosynthetic communities at Gulf of Mexico hydrocarbon vents

The analogy between desert oasis and deep-sea chemosynthetic community arose from the biomass contrast between vents and the relatively depauperate background benthic fauna. Fully developed, the analogy helps pose questions about interactions with the background fauna with respect to resources, colonization, and persistence. The chemosynthetic sites of the Gulf of Mexico provide an opportunity to consider possible interactions between vent and nonvent fauna over a 3000-m depth range. It is postulated that deep chemosynthetic communities require the operation of geochemical transporting and concentrating processes to overcome low levels of in situ methane and sulfide production. Clathrate reservoirs may serve these functions. A few chemosynthetic species at the Gulf of Mexico upper slope sites are related to shallow-water sulfide species, but it can be speculated that the dominant chemosynthetic fauna may have originated in a wide spread deep sulfide biome of the Cretaceous. Generic endemism of consumers is low in Gulf of Mexico sites, suggesting a high level of colonization from the surrounding benthos. Chemosynthetic communities may avoid excessive colonization by predators in spite of the apparent food limitation of the surrounding benthos due to toxicity or an evolutionary mechanism selecting against specialized predators. The abundance of large predators is related to the composition of the surrounding benthos and is high at the Gulf of Mexico upper slope sites. Exclusion of chemosyntheic communities from shallower depths may be due to excessive predation by generalists.
The organization of the MCT workshop: an innovative approach to universities, industry, and government working together

This workshop was organized in the early 1980s to produce HgxCd1−xTe (MCT) mid- and long- wave infrared night vision technology. A key was an organizational plan that would combine industry, university, and government work to optimize return on the overall investment. (A majority of the work was sponsored by the U.S. Government.) To put this in perspective, three models will be presented, going from basic work to manufacturing a product. These are the series, parallel, and hybrid models. The workshop fits the parallel model best and can be thought of as a pioneering attempt in implementing such a model.
“Green” composites and nanocomposites from soybean oil

Abstract In this study, we report preparation of epoxidized soybean oil (ESO)-based “green” composites and nanocomposites. The high strength and stiffness composites and nanocomposites are formed through flax fiber and organoclay reinforcement. The epoxy resin, 1,1,1-tris(p-hydroxyphenyl)ethane triglycidyl ether (THPE-GE) is used as a co-matrix for flax fiber-reinforced composites. For the clay-reinforced nanocomposites, the dispersion of the clay layers is investigated by X-ray diffraction (XRD) and by transmission electron microscopy (TEM). XRD and TEM data reveal that the intercalated structure of ESO/clay nanocomposites has been developed. Mechanical properties of both materials are investigated. As curing agent, triethylenetetramine (TETA) is used for both systems.
On the conditions for enhanced transport through molecular junctions based on metal centres ligated by pairs of pyridazino-derived ligands

Transport properties of a Ni bis-η2 complex ligated by a pair of bi-pyridazino derivative are considered. This complex provides the opportunity to avoid perpendicular alignment of the ligand π planes. We study the effects of π-bonding and of intramolecular hydrogen bonding between the ligands as mediated by the metal centre on electron transport. The complicated effect of the electronic structure equilibration with the electrodes on the transport is discussed. The analysis at the electronic structure level provides guidelines to design a molecular bridge that is based on metal complexation with effective electronic transport.
Radioactive 26Al measured on LDEF satellite clamps – What is its source?

Abstract Since 1984 astrophysicists have speculated on the original source of the 26Al measured by the HEAO 3 satellite gamma-ray telescope. With a half-life of 717 000 years it cannot be primordial, and the Sun cannot produce it. Possible sources suggested have included gamma radiation directly from various astronomical entities, such as novae, supernovae, AGB stars or Wolf–Rayet stars, or radiating particles from some of those sources present in the local interstellar medium. It has also been suggested that some of the 26Al gamma radiation being observed might be coming from grains produced in nearby supernovae, or from cosmic-ray spallation reactions occurring on heavier atoms in space. These atoms or particles might have been swept down into the local interstellar medium by the solar or stellar winds. Using a multidimensional gamma-ray spectrometer we have measured the disintegration rates of 26Al on four clamps which flew for 5.8 years on the Long Duration Exposure Facility satellite. Evaluation of possible local internal production of 26Al by cosmic-rays during the known flight path of the satellite has determined that the observed 26Al disintegration rates of the four clamps range from 17 to 32 times the rates from local production. Thus, the 26Al observed is likely from space, confirming earlier discoveries of its presence in the local interstellar medium. Based on our measurements, a tentative maximum value of 0.000052 ± 0.000006 atoms cm - 3 is derived for the density of 26Al in near Earth space.
Method for culturing the phantom midge, Chaoborus (Diptera: Chaoboridae), in the laboratory

Abstract Chaoborus punctipennis (Say) was cultured in a cage positioned over an aquarium containing lake water, sediments, and artificial plants. During a 40-day period, 61 fertilized egg rafts were laid yielding approximately 21 130 first instars. Egg rafts averaged 380 eggs (n = 23) with 91.2% hatching success. First and second instars were fed rotifers and/or protozoans, third instars were fed a mixture of rotifer and crustacean zooplankton, and fourth instars received only the latter. At 19°C and with excess food, the shortest development time from egg to pupal stage was 15 days. First and second instars required food before molting to the next stadia. Median starvation times for the first and second instars at 12°C was 6.1 and 7.4 days, respectively. This is the first successful culturing method for a lake-dwelling Chaoborus species and modifications of this method should be successful for culturing other Chaoborus species.
10-Keto opiates

Abstract The benzylic oxidation of N -cyclopropylcarbonylnordihydrodesoxy-codeine with selenium dioxide for the preparation of the 10-keto derivative is described.
Global optimization of general non-convex problems with intermediate bilinear substructures

This work considers the global optimization of general non-convex nonlinear and mixed-integer nonlinear programming MINLP problems with underlying bilinear substructures. We combine reformulation–linearization techniques and advanced convex envelope construction techniques to produce tight subproblem formulations for these underlying structures. When incorporated as linear cutting planes, these relaxation strengthening strategies are highly effective at tightening standard linear programming relaxations generated by factorable programming techniques. Because the size of these augmented linear relaxations increases exponentially with the number of variables, we employ cut filtering and selection strategies to ensure that the tightened subproblems are solved efficiently. We introduce algorithms for bilinear substructure detection, cutting plane identification, cut filtering, and cut selection and embed the proposed implementation in Branch-and-Reduce Optimization Navigator at every node in the branch-and-bound tree. A computational study including problem instances from standard literature test libraries is included to assess the performance of the proposed implementation. Results show that underlying bilinear substructures are identified in 30% of the problems in GLOBALLib and MINLPLib and that the exploitation of these structures significantly reduces computational time, branch-and-bound tree size, and required memory.
Dying: A Universal Human Experience?

This paper explores the question, "Is there a universal psychological experience suffered by all dying persons?" a question to which the popular theory of Kubler-Ross presupposes an affirmative answer. Our answer takes three steps: first, a comparison between the Kubler-Ross model of dying and that of the late medievalBook of the Craft of Dying centered upon the five Kubler-Ross "stages"; second, a philosophical critique of the terms of this comparison; and third, a revised look at the alleged similarities between the two models, providing a deeper look at the moral and spiritual assumptions behind each.
Maximalj-Simplices in the Reald-Dimensional Unit Cube

For each positive even integerjthere is an infinite arithmetic sequence of dimensionsdfor which we construct aj-simplex of maximum volume in thed-dimensional unit cube. For fixedd, all of these maximalj-simplices have the same Gram matrix, which is a multiple ofI+J. Forjeven, a new upper bound for the volume of aj-simplex in thed-dimensional unit cube is given
Cocaine and the porcine coronary microcirculation: effects of chronic cocaine exposure and hypercholesterolemia.

Objective: To examine the acute effect of cocaine on the coronary microcirculation and whether chronic cocaine administration with or without a concomitant high-cholesterol diet affects β-adrenoceptor and endothelial functions in the coronary microcirculation. Design: Prospective experimental study. Setting: Laboratory and animal research facility. Participants: Yorkshire pigs. Interventions: Pigs were fed a high (2%)-cholesterol diet or a regular diet for 3 months. Animals in both groups received cocaine chronically (7 mg/kg/day, IM). Control animals were fed a regular diet. Measurements and Main Results: Responses of the porcine coronary arterioles (90 to 190 m in diameter) were examined in vitro in a pressurized (40 mmHg) no-flow state using a video-imaging apparatus. Acute application of cocaine caused a significant contraction with a mean maximal diameter decrease of 14% ± 5%, which was markedly reduced by muscarinic blockade but not significantly affected by α1-adrenergic blockade. Lidocaine or procainamide had no vasoconstrictor effect. Chronic exposure of animals to cocaine diminished contractile responses to cocaine and reduced relaxation responses to the nonselective β-adrenergic receptor agonist isoproterenol. Phenylephrine caused a minimal ( Conclusions: These results suggest that cocaine can exert a direct vasoconstrictor effect on the porcine coronary microcirculation via a muscarinic mechanism. Chronic exposure to cocaine significantly decreases β-adrenoceptormediated relaxation and blunts endothelium-dependent relaxation to a small degree.
Gabapentin decreases membrane calcium currents in injured as well as in control mammalian primary afferent neurons.

Background and Objectives: Neuropathic pain following injury to peripheral sensory neurons is a common clinical problem and frequently difficult to treat. Gabapentin (GBP), a novel anticonvulsant, has significant analgesic effects in clinical neuropathic states and in relevant preclinical models, but its mechanism of action remains unclear. Because calcium currents play a significant role in neuronal function, this study was designed to assess the effect of GBP on the membrane voltage-activated inward calcium currents (ICa) in dorsal root ganglia (DRG) primary afferent neurons of neuropathic versus control rats. Methods: Male rats were prepared according to the chronic constriction injury (CCI) model. The L4 and L5 dorsal root ganglia of those selected as CCI or control after appropriate behavioral testing were removed, and neurons were enzymatically dissociated. Fluorescent dye (DiI) placed at the injury site allowed identification of neurons projecting to that site. These were acutely studied using whole-cell, perforated (with [beta ]-escin) patch-clamp recordings. Additionally, neurons from sham or nonoperated rats were also studied. Results: Although there was marked variability among cells, concentrations of GBP ranging from 0.1 to 300 [mu ]mol/L decreased neuronal peak ICa in midsized neurons (30 to 40 [mu ]m) of both sham and neuropathic rats, in a fast, reversible, and concentration-dependent manner. Intergroup differences were not significant, however the concentration-response EC50s were 2.7 [mu ]mol/L for the sham and 16.5 [mu ]mol/L for the CCI neurons. The drug suppressed ICa in nonoperated rats to a lesser degree, but changes did not differ significantly from the operated groups. Calcium currents in either small or large diameter neurons were also variably decreased by 10 [mu ]mol/L of GBP in sham and CCI neurons. Current inhibition by GBP was partly voltage dependent. Conclusions: GBP, at clinically relevant concentrations, results in significant reduction of ICa in both sham and neuropathic neurons, while in nonoperated rats reduced ICa to a smaller degree. Sensitivity to drug was not affected by neuropathy. This current inhibition is partly voltage dependent. Depression of ICa may be partly related to the binding of the drug to the [alpha ]2[delta ] modulatory subunit of the voltage activated calcium channels (VACC). Analgesia may be due to diminished release of neurotransmitter by sensory neurons, a Ca2+-dependent process. Reg Anesth Pain Med 2002;27:47-57.
Stark broadening and stimulated Raman pumping in high-resolution N2 coherent anti-stokes Raman scattering spectra

In previous studies, the high-resolution N 2 coherent anti-Stokes Raman scattering (CARS) technique has been used to acquire pressure, temperature, and density measurements in high-speed supersonic e ows. In these lowdensity e ows, a tradeoffexistsbetween elevating theCARS signal strength with increasing pump- and Stokes-laser intensities and introducing Stark broadening and stimulated Raman pumping effects into the high-resolution N 2 CARS spectra. To explore these laser-induced perturbations, theCARS technique is used to acquire v =0 ! 1 and v =1 ! 2 CARS spectra over a range of pressures in an optically accessible gas cell. By controlling the intensity of the pump- and Stokes-laser beams, Stark broadening effects in the high-resolution (D ! =0:10 cm i 1 ) broadband CARS spectra are explored. For pump-laser intensities greater than 185 GW/cm 2 , the least-squares e ts of the experimental spectra with theoretical spectra provide pressures and temperatures that diverge from conditions measuredwithin thecell usingconventional transducersforpressuresandtemperaturesaround0.2 atm and298K, respectively. An analytical model based on rigid-rotator harmonic-oscillator theory is used to describe how the increased optical e elds of the pump and Stokes lasers stretch the molecular bond between the nitrogen nuclei, broadening and shifting the rotational transitions in the Q-branch manifold. Finally, by increasing the pump- and Stokes-laser intensities simultaneously, ambient v=1 ! 2 N2 CARS spectra, resulting from stimulated Raman pumpingeffects,areacquiredwithhighresolution.Least-squarese tsoftheseexperimentalspectrawiththeoretical spectra show that stimulated Raman pumping signie cantly increases the vibrational temperature extracted from the experimental spectra. The relative intensities of the rotational transitions in the v=0 ! 1 manifold, however, are not affected by the stimulated Raman pumping process.
Simulation Based Optimization of Microfluidic Devices Used for Molecular Enrichment

Microfluidic devices are used in several engineering fields ranging from biomedical to chemical to engineering for applications such as micro reactor, target molecular enriching and cell capturing. With regard to related applications, microfluidic devices offer advantages such as high surface area to volume ratio, increased mass transfer coefficient and portability in addition to their requirement of low analytes. Affinity based microfluidic devices with microscale posts have high compactness and mass transfer coefficient. In order to maximize the benefits offered by employing microfluidic devices, it is important to apply parametric study in the device designing work. This study is aimed at studying the operating and geometric parameters of microfluidic devices with square/rectangular microscale posts. The geometric parameters, such as aspect ratio of the microposts used, could possibly decide the performance of the device. Operating parameters studied are Reynolds number, Peclet number, Damkohler number, and equilibrium reaction constant. These parameters encompass the influence of velocity, diffusivity, density, viscosity, hydraulic diameter, inlet concentration of species and absorption/desorption reaction constants.This work theoretically analyzes the influence of the above mentioned parameters using COMSOL Multiphysics 4.2.a. The governing equations of microfluidic devices, i.e. Navier-Stokes equations and the advection-diffusion equation, subjected to the above mentioned operating parameters, are solved to obtain the velocity profile, pressure drop and concentration profile of the species. The metric used for analyzing the influence of each operating parameter is the capture efficiency, i.e. the ratio of outlet concentration to inlet concentration as well the pressure drop. The results of this study would improve the design of microfluidic devices used for chemical reactions as well as that used for protein enrichment.Copyright © 2012 by ASME
Experience in Full-Load Testing of Natural Gas Centrifugal Compressors for Rotordynamics Improvements

During full-load shop tests under natural gas, two multistage centrifugal compressors exhibited subsynchronous vibrations. Both of them are low-flow, high-pressure, high rotational speed compressors, and are fitted with tilting pad bearings and dry gas seals. A rotating stall problem was first eliminated by a modification of the diffuser geometry. Then, aerodynamic excitations caused the rotors to operate at their stability limit, and high vibration levels were observed at the first natural frequency. A complete rotordynamics analysis was performed in order to model precisely all the fluid-structure interactions. Modifications of the rotor designs were implemented, consisting in optimizing conveniently the bearing pads, replacing the toothed labyrinth seals of the balance. pistons by damping honeycomb seals, fitting them with improved shunt hole systems. In addition, the dry gas seals were found to have been damaged, due to thermal effects, and further modifications were implemented to eliminate this problem. Final full load tests demonstrated a satisfactory behavior of both centrifugal compressors.
A Systems Approach to Discrete Event Controller Design for Manufacturing Systems Control

A modern systems theory point of view is offered for the design of sequencing controllers for discrete event manufacturing systems. The controller is an intelligent rule-based system with inner loops where no conflict resolution (CR) is required and outer loops where CR is needed. The CR approach ensures that the closed-loop system is decision-free. The most suitable CR strategy depends on the-performance desired from the system.
Interactions between soil, rainfall, and wildlife drive surface water quality across a savanna ecosystem

Surface water resources play an important role in the transportation of nutrients within and between regions. Water quality varies spatially across landscapes, but the extent of this variability and the interaction between water quality and wildlife are not well-known. In some savannas, heterogeneous climatic and geologic patterns result in gradients of precipitation and soil nutrients, leading to temporal and regional differences in soil and vegetation quality. Wildlife utilise these seasonal patterns, influencing soil nutrient dynamics and vegetation. However, the impact of seasonally abundant wildlife, climate, and soils on surface water quality is unknown in savannas. Fluctuations in surface water quality were measured across the Serengeti ecosystem at 6-month intervals, and the influence of rainfall, watershed, and seasonal wildlife migration were then modelled. The results suggest that although soil composition in watersheds influences the concentration of soil-derived nutrients in rivers, rainfall and wildlife have a significant effect on the seasonal concentrations of most nutrients. The role of migratory wildlife in surface water quality in some watersheds is likely dampened by the large influence of resident species across seasons and habitats. The alteration of rainfall patterns by climate change is expected to influence nutrient transport into savanna rivers. Copyright © 2012 John Wiley & Sons, Ltd.
On Saying What There Is

This is an effort to say something about one sort of connection between language and the world. But what is the claim being made? Surely not just that the world cannot be described without the use of a descriptive medium, a language. That would be like saying that there could be nothing called a table unless there were the word 'table'. Nor does it mean that saying somehow makes things so. It is not a claim about the conditions under which particular descriptions are true. To say-truthfully-that there is a table before me I must have the word, but there must, in addition, be a table before me. No one wants to deny that. The claim is not about the connections of particular descriptions to the world, but a broader claim about the connection between our way of talking and the pieces into which the world is 'carved'. I shall not expand on the quoted passage. I am not clear which, if any, of the views I want to take up is defended by its author. I should like to discuss one natural interpretation of the passage without imputing that interpretation to the author. The view expressed seems to run something like this. It is senseless to imagine that the world comes 'pre-carved', 'ready to label'. The divisions we make, the seams we locate, are not found but imposed. Objects, for example, have the boundaries they have because those are the boundaries we have decided on. Nothing in the nature of things forces such choices. \WVe might have decided to draw the boundaries differently. Had we done so, we would now be living in a different world. Not that the world would be changed; for change is itself something that requires a mediating system of concepts and their associated boundaries. There may, it is true, be certain broad constraints on the divisions we impose. We might, for example, imagine a world in which it would be difficult or impossible to employ words standing for what we call events. But it would be misleading to put this last point in terms of our imagining the world's being different. On the other hand, human beings may, purely as a matter of contingent fact,
Do the Determinants of Promotion Differ for Blacks and Whites? Evidence from the U.S. Labor Market.

A central assumption of much of the previous research on race differences is that the process by which Blacks and Whites advance in the workplace is race blind so that if Blacks and Whites had the same amount of education and job experience and were located across the same bureaucratized structures, the gap in Black-White attainment in the workplace would disappear. The authors argue that to understand the systematic differences in Black-White outcomes in the workplace, we need to reexamine this assumption. The authors develop a theoretical argument for the existence of race-specific models of attainment that builds on Kanter's concept of “homosocial reproduction.” They then test this argument by estimating whether the determinants of promotion differ by race, using a nationally representative sample of U.S. workers and their employing organizations. Their findings indicate that the determinants of promotion systematically differ for Blacks and Whites.
An endochronic prediction of the variability in fracture times of polymers

A theory of variability in lifetimes of identical polymer specimens under identical test conditions is formulated, using the theory of fracture of amorphous crosslinked polymers developed previously by the authors. Variability in fracture times follows from the assumption that the critical number Ncr of bonds that must fail in order to cause fracture of a specimen varies from specimen to specimen. A plausible physical explanation for the variation in Ncr may well lie in the variability of the spatial distribution of weak local regions. The scale of locality may vary from molecular to grosser dimensions. The theory is applied to styrene–butadiene rubber (SBR) under creep conditions and fares well in its prediction of observed results. Most notably, it predicts that the shape of the distribution curve of the observed lifetimes remains invariant with changes in the levels of stress and temperature and that the effects of these manifest themselves through shifts of the curve on the logarithmic time axis. The theory also predicts correctly that the fracture process is accelerated if the creep test is interrupted by unloading–reloading cycles at high strain rates. This last result is shown to be a direct consequence of the concept of “the endochronic time to fracture,” previously introduced by the first author.
Impact of the Safe Routes to School program on walking and biking: Eugene, Oregon study

Policymakers in many countries, including the United States, United Kingdom, and Australia, have introduced programs to increase walking and biking to school through education, encouragement, and infrastructure improvements. The U.S. government has allocated over $1.1 billion to the federal Safe Routes to School program since 2005. However, there are few evaluations of the Safe Routes to School program. Our study used a robust quasi-experimental research design to measure the impacts of Eugene, Oregon's Safe Routes to School program on walking and biking. Using data collected between 2007 and 2011 at 14 schools with and without Safe Routes to School programs, we showed that the Safe Routes to School program was associated with increases in walking and biking. Education and encouragement programs were associated with a five percentage point increase in biking. Augmenting education programs with additional SRTS improvements such as sidewalks, crosswalks, covered bike parking, and Boltage was associated with increases in walking and biking of 5–20 percentage points. The study results illustrate the potential for the Safe Routes to School program to change behavior and should encourage other communities to plan for multi-modal school travel.
Interactions between Buprenorphine and Antiretrovirals. I. The Nonnucleoside Reverse-Transcriptase Inhibitors Efavirenz and Delavirdine

This study examined drug interactions between buprenorphine, an opioid partial agonist medication used in the treatment of opioid dependence, and the nonnucleoside reverse-transcriptase inhibitors (NNRTIs) efavirenz (EFV) and delavirdine (DLV). Opioid-dependent, buprenorphine/naloxone-maintained, human immunodeficiency virus (HIV)-negative volunteers (n=10 per NNRTI) participated in 24-h sessions to determine pharmacokinetics of buprenorphine and of buprenorphine with either EFV or DLV after administration of standard doses of either antiretroviral for 15 or 7 days, respectively. Opiate withdrawal symptoms, cognitive effects, and adverse events were determined before and after antiretroviral administration in opioid-dependent participants. The pharmacokinetics of NNRTIs in healthy control participants were used to determine the effect of buprenorphine on NNRTIs. EFV decreased the buprenorphine area under the concentration-time curve (P<.001). DLV increased buprenorphine concentrations (P<.001). Clinically significant consequences of these interactions were not observed. Buprenorphine did not alter antiretroviral pharmacokinetics. Adjustments of doses of either buprenorphine or EFV or DLV are not likely to be necessary when these drugs are administered for the treatment of opiate dependence and HIV disease.
Mineral production, territory, and ethnic rebellion: The role of rebel constituencies:

Several possible relationships between natural resources and civil conflict have been hypothesized and tested in the literature. The impact of resources on conflict should depend on the circumstanc...
Sensor fusion cognition using belief filtering for tracking and identification

Humans exhibit remarkable abilities to estimate, filter, predict, and fuse information in target tracking tasks. To improve track quality, we extend previous tracking approaches by investigating human cognitive-level fusion for constraining the set of plausible targets where the number of targets is not known a priori. The target track algorithm predicts a belief in the position and pose for a set of targets and an automatic target recognition algorithm uses the pose estimate to calculate an accumulated target-belief classification confidence measure. The human integrates the target track information and classification confidence measures to determine the number and identification of targets. This paper implements the cognitive belief filtering approach for sensor fusion and resolves target identity through a set-theory approach by determining a plausible set of targets being tracked.
Gasket seal closure for extended endonasal endoscopic skull base surgery: efficacy in a large case series.

Objective To assess long-term efficacy of the gasket seal, a method for watertight closure of the cranial base using autologous fascia lata held in place by a rigid buttress, in a large case series. Methods A prospectively acquired database of all endonasal endoscopic surgeries performed over a 5-year period at Weill Cornell Medical College starting in September 2005 was reviewed. Results The gasket seal was used in 46 consecutive patients. Mean age was 53 years (range 7–83 years). All patients had extensive intracranial disease with a significant intraoperative cerebrospinal fluid (CSF) leak. Pathology included craniopharyngioma (39.1%), meningioma (23.9%), and pituitary adenoma (17.4%). After a mean follow-up of 28 months (range 3–63 months), two (4.3%) patients had a postoperative CSF leak. Excluding the patients with adenomas, the CSF leak rate was 5.2% (2 of 38 patients). One leak was controlled with reoperation, and the other was stopped with a lumbar drain (LD). The significance of pathology, type of approach, exposure of the ventricular system, use of fat graft, use of nasoseptal (NS) flap, and use of lumbar drain (LD) was examined, and none of these were significant predictors of postoperative CSF leak. Conclusions Gasket seal closure is a reliable long-term effective method for achieving watertight closure of the cranial base. It can be used in association with an intracranial fat graft, NS flap, LD, and tissue sealants. In this series, none of these other factors were significant predictors of postoperative CSF leak.
Second-order correction to the Λ binding energy in nuclear matter

Abstract The second-order correction to the Λ binding energy in nuclear matter evaluated in the independent pair approximation is found to be small.
Communication in the tele-ICU

Objective: To systematically describe communication between tele-ICU (Intensive Care Unit) nurses and bedside nurses in multiple ICUs, the strengths and weaknesses of communication in the tele-ICU and possible solutions for improving communication. Background: Nurses in tele-ICUs function in virtual teams whose configuration and membership is constantly and rapidly changing. This research examines communication and technological support for communication in the multiple virtual teams formed by tele-ICU nurses and ICU nurses. Methods: A case study research approach using mixed data collection methods. One tele-ICU that monitors 16 ICUs in 12 hospitals across the US participated in this study. Results: Tele-ICU nurses spend 26% of their time in communication-related activities. Fifteen percent of tele-ICU nurses surveyed reported getting incorrect information from ICU nurses and 40% reported that they are not informed in a timely manner about a change in patient status. Frequency of communication between te...
A CMOS linear-in-dB variable gain amplifier for low power read channel front-end

A linear-in-dB CMOS variable gain amplifier (VGA) targeting a low power read channel front-end is presented. Biased with a less than 2 mA current, this VGA provides 6-18 dB amplification and more than 700 MHz 3-dB bandwidth with less than -45 dB THD in 0.18-mum CMOS. In addition, the 6-18 dB gain is continuously tunable by adjusting the bias current. With such a performance trade-off, it is well suited for mobile storage applications.
Sensitivity of optical interferometers with coherent image combination

When multiple, adaptively-corrected telescopes are coherently combined at a common focal plane, interference appears as spatial structure in the point spread function (PSF). True images of deep fields can be reconstructed at resolution λ/b from multiple images recorded to cover the u-v plane with baselines up to b. Assuming no losses or detector noise, sensitivity improves with the number of elements, n, and of combined images, N. The formalism of PSF fitting is used here to determine signal/noise ratio for faint point sources seen against sky background noise. For two-element and dilute, non-redundant arrays the PSF fit is dominated not by any sharp peak, but by fringes or weak speckles, and the signal/noise ratio is proportional to square root N(2n-1). For close packed or highly redundant arrays the sensitivity increases as nsquare root N, and is the same as for a single dish with the same total collecting area and integration time. It follows that the signal/noise ratio for a two-element array is thus square root 3/2 = 86% of this maximum limit. We show that the requirement for PSF sampling with negligible detector read noise can be met with available optical and infrared array detectors, for baselines up to 10 times the element diameter. Low-loss combination could be realized in practice by an interferometer with two large moving elements, with baselines set up sequentially to sample the full u-v plane. In the 20/20 concept, two 21 m telescopes move continuously around a circular track during an integration, to keep the baseline oriented perpendicular to the source. Coheret combination is made at a station held midway between, to obtain aperture synthesis of images covering the full, one arc-minute field corrected by multiconjugate adaptive optics. With 16 images taken over 8 hours to fully cover baselines up to 100 m, the resolution in the K band is 4 mas, and the 10σ limiting magnitude for point sources will be 27.7.
Effectiveness of multiple EEGs in supporting the diagnosis of epilepsy: an operational curve

Interictal epileptiform activity (IIEA) on EEG may be useful in the diagnosis and characterization of epilepsy. A single scalp EEG may fail to detect this abnormality, which is then discovered on repeat recordings. Since many people with epilepsy have persistently normal EEGs, a practical question arises concerning the yield of multiple EEGs. To determine the probability of finding IIEA with serial EEGs (the operational curve), we reviewed data from 1,201 EEGs on 429 adult patients, most with definite epilepsy presenting in adulthood. The diagnosis was made either clinically or with the support of the EEG. In 50% of our patients with IIEA, the abnormality is present on the first record, in 84% by the third EEG, and in 92% by the fourth. There is relatively little yield to serial EEGs beyond this point.