cssi/SciSciGPT-SciSciNet huggingface dataset:
SU-D-303-06: Evaluations of Quantified Magnetic Moments From Different MRI Hardware

Purpose: Our quick study here is to validate whether the quantified magnetic moments of the same object are the same from different MRI machines and rf head coils. Methods: We constructed a gel phantom consisting of an empty straw with a diameter of 2.6-mm, a 3-mm diameter glass bead, and a 5-mm diameter glass bead. We imaged the phantom with a 4 echo gradient echo sequence on a 1.5-T Siemens Sonata and a 3-T Verio. On the 1.5-T, we used a quadrature single-channel birdcage coil and an 8-channel coil. On the 3-T, we used a single channel circular-polarized (CP) receiving coil and a 12-channel coil, which outputs only 4 channels. After removing the background phase with the SHARP method [1], we quantified magnetic moments of the three objects at each echo time for each coil, using the CISSCO method described in [2, 3]. Results: The quantified magnetic moments for each object are consistent among 4 echo times and different hardware. In addition, the quantified values agree with the expected values within uncertainties. Conclusion: For each of the three objects, we have demonstrated self consistencies of quantified magnetic moments between four different setups at four different echo times, using the CISSCO method. These results support that, with the appropriate post processing procedures and methods applied on images acquired from any MRI hardware or imaging parameters, we should obtain the same magnetic moment of the same object of interest. However, phase images improperly post processed may or may not lead to the correct quantified magnetic moment of the object. Post processing methods such as quantitative susceptibility mapping or combination of phase images from individual rf channels require further studies. Ref:[1] Schweser et. al, NeuroImage, 2011, pp. 2789–2807. [2] Cheng et. al, MRI, 2015, in press. [3] Cheng et. al, PMB, 2009, pp. 7025–7044. DOD/USAMRAA W81XWH-12-1-0522
Comparison Between Lightly Crosslinked Ionomeric Materials and Highly Crosslinked Materials Derived from Poly(Acrylic Acid) with Organostannanes as the Crosslinking Agent

Ionomers are ion-containing polymers in which the ion-containing segment is present in only a small amount (1). Here the ionomer is a carboxylic ester or acid-containing polymer derived from the copolymerization of the acid-containing monomer and ethylene. Ionomers are usually neutralized by addition of a mono or divalent cation. Here the carboxylic acid is neutralized through reaction with sodium hydroxide with subsequent reaction with organostannane halides(2). While they can be considered to be crosslinked, they are thermoplastics, melting under application of heat and pressure.
Mass discrimination monitoring and intercalibration of dual collectors in noble gas mass spectrometer systems

Accurate high-precision 40Ar/39Ar ages are limited, in part, by the degree of accuracy and precision of the measurement of the 36Ar atmospheric Ar contamination correction and the mass spectrometer mass fractionation bias (mass discrimination) correction. To improve the measurements of the low-level 36Ar signals, we have implemented digital ion-counting and multicollector data acquisition methods. The switch to the digital ion pulse counting method results in a tenfold improvement in the signal-to-noise ratio relative to analog electron multiplier measurements that are in general use in most 40Ar/39Ar laboratories. The use of ion pulse counting significantly improves low-level signal (36Ar) measurements. The improvement in low-level 36Ar measurements, however, comes at the cost of a reduced dynamic range of the electron multiplier detector, thus requiring the use of an alternate detector at times, such as a Faraday cup or analog multiplier for large signals. In turn, this requires accurate intercalibration of the detectors. Here we present a protocol that addresses these issues, one that closely tracks changes in the mass spectrometer mass discrimination and the detector intercalibration (IC) factor(s) during the time frame of an experiment, thereby improving measurement accuracy. A major advantage of our protocol is that the procedure uses the same aliquots of atmospheric Ar to monitor mass discrimination and detector IC factors, saving a significant amount of measurement time. In addition, this IC protocol may address the cause of reported inaccuracies in the measured isotopic ratio data on the “new” generation multicollector mass spectrometers. Further, we present a “time series protocol” that monitors any temporal drift in the mass spectrometer mass fractionation bias that can occur due to laboratory environmental changes.
What Drives Media Bias? New Evidence From Recent Newspaper Closures

With the advent of the Internet, many U.S. metropolitan areas have seen newspaper closures due to declining revenues. This provides the researcher with an opportunity to analyze the microeconomic sources of media bias. This article uses a large panel dataset of newspaper archives for 99 newspapers over 240 months (1990–2009). The author found that, after controlling for the unemployment rate, the change in unemployment rate, and the political preferences of surrounding metropolitan area, conservative newspapers report 17.4% more unemployment news when the President is a Democrat rather than a Republican, before the closure of a rival newspaper in the same media market. This effect is 12.8% for liberal newspapers. After the closure, these numbers are 3.5% and 1.1%, respectively. This moderation of media bias after closure of a rival newspaper is robust to the inclusion of newspaper size, newspaper fixed-effects or metropolitan area fixed-effects as controls. The author also found that newspapers in smaller...
The Virtue of a Natural Law Reading of the U.S. Constitution

Natural law was arguably fundamental to the U.S. Constitutional project: the Framers apparently assumed courts would interpret and apply unwritten natural law concepts alongside the enacted provisions of the document. However, since the early 19th Century judges have sought to ground all decisions on specific text in the Constitution. Not only is this inconsistent with the intent of the Framers, it makes for bad adjudication. Fortunately, I believe philosophy and custom can be marshaled on the side of re-introducing judicial appeal to natural law. Philosophically, the fact that the positivist conception of law has no connection to ethics or natural law principles makes it ontologically bankrupt - unlike natural law, positive law has no ontological validity at its core. Natural law is also inherently primary to positive law - in the sense that moral imperatives shape positive law, and in the sense that interpreting positive law requires higher guiding principles. The existence of a long-standing custom of judicial appeal to natural law provides an ethical basis for judicial creativity in protecting rights that flow from natural law principles. As to a model framework, I argue that judges are competent to apply a range of faculties in ascertaining our society’s moral true north. I offer that virtue ethics, and specifically the venerable tradition of the middle path - the doctrine of the mean - can provide a framework which holds promise as a universal principle that can assist us in re-evaluating and re-creating our fundamental law as our social experiment in the United States develops.
Approximation algorithms for two optimal location problems in sensor networks

This paper study two problems that arise in optimization of sensor networks: First, we devise provable approximation schemes for locating a base station and constructing a network among a set of sensors each of which has a data stream to get to the base station. Subject to power constraints at the sensors, our goal is to locate the base station and establish a network in order to maximize the lifespan of the network. Second, we study optimal sensor placement problems for quality coverage of given domains cluttered with obstacles. We assume "line-of-site", sensors, that sense a point only if the straight segment connecting the sensor to this point (the "line-of-site") does not cross any obstacle. so obstacles occludes area from using line-of-site sensors, the goal is to minimize the number of sensors required in order to have each point "well covered" according to precise criteria (e.g., that each point is seen by two sensors that form at least angle a, or that each point is seen by three sensors that form a triangle containing the point).
Continuous-wave self-mode-locked operation of a femtosecond Cr 4+ :YAG laser

Continuous-wave self-mode-locked operation of a chromium-doped YAG laser pumped by a continuous-wave Nd:YAG laser at 20 °C is described. We used both regenerative initiation and continuous-wave self-mode-locking techniques to generate nearly transform-limited pulses of 120-fs (FWHM) duration at 1.52 μm. The TEM00 output power was as high as 360 mW. The output of this femtosecond source was tunable from 1.51 to 1.53 μm.
A proposed NSLS X-ray ring upgrade using B factory technology

A proposed upgrade to the NSLS X-Ray Ring is described that will allow the storage of a 2.4 A, 3 GeV electron beam using technology developed for the PEP-II B factory at SLAC. In this configuration, a peak flux of greater than 1016 photons/sec/0.1% bandwidth/5 mrad will be produced. The four existing 53 MHz RF cavities will be replaced with eight 476 MHz cavities. Two 952 MHz cavities will also be used to lengthen the bunch, increasing the Touschek life-time. A copper vacuum chamber will be needed to absorb the increased synchrotron radiation and a feedback system may be needed to prevent multi-bunch instabilities.
The Inhibition by Phlorizin of Kidney Microsomal Inorganic Pyrophosphate-Glucose Phosphotransferase and Glucose 6-Phosphatase

Abstract Glucose 6-phosphatase from rat liver and kidney microsomes previously has been shown to catalyze an inorganic pyrophosphate-glucose phosphotransferase reaction. Nordlie and Soodsma recently have suggested that formation and then degradation of glucose 6-phosphate by the combined action of phosphotransferase and phosphohydrolase activities of this enzyme may under certain conditions constitute part of a mechanism for facilitated transport of glucose across the kidney tubular cell. To attempt to gain additional insight regarding the possible significance of such a physiological role for the enzyme, studies of the effect of phlorizin, a potent inhibitor of tubular sugar transport, on both phosphohydrolase and phosphotransferase activities of this enzyme were undertaken. Inhibition, in vitro, of both glucose 6-phosphate phosphohydrolase and pyrophosphate-glucose phosphotransferase activities of kidney homogenates and microsomal suspensions prepared in isotonic sucrose solution was noted over the entire range of phlorizin concentrations studied, 6.7 x 10-5 m to 6.7 mm. Sensitivity of activities to inhibition by this compound was either partially or completely abolished by supplementation of the homogenates or microsomal suspensions, to 0.2% (w/v), with sodium deoxycholate, sodium cholate, digitonin, Triton X-100, or Tween 20. Phlorizin was without discernible effect on activity of partially purified enzyme preparations obtained by fractional ammonium sulfate precipitation of deoxycholate-dispersed microsomal suspensions. Inhibition of phosphotransferase activity in homogenates or microsomes was markedly potentiated by the cationic detergent trimethylhexadecylammonium bromide. Kinetic analyses indicated that inhibition of both phosphohydrolase and phosphotransferase activities by phlorizin was of the classical noncompetitive type. A value of approximately 0.7 mm for Ki for phlorizin was determined in the absence of detergent; the value was reduced to 0.2 InM when trimethylhexadecylammonium bromide was added (to 0.2%, w/v) to enzyme preparations prior to assay for activity. The effects of the administration in vivo of phlorizin on phosphotransferase activity of the enzyme were also studied. Reductions in activity per mg of kidney protein of as much as 18% were produced by intravenous injection of 0.1-g doses of phlorizin to rats. The data obtained appear to rationalize the initially apparently contradictory reports of earlier workers regarding the effects (or lack of effect) of phlorizin on glucose 6-phosphatase. The experimental observations reported in this paper also are interpreted to constitute added support for, but not direct proof of, the possible involvement of synthetic and hydrolytic activities of this enzyme in kidney glucose transport. It is suggested that the modifying effects of various detergents on phlorizin-sensitivity of the enzyme are manifest through selective action on both active and inactive "silent" phlorizin-binding sites in the enzyme preparation.
Animal Screening Systems

Animal screening systems are experimental protocols designed primarily to screen substances in laboratory animals for possible adverse effects in humans. These experiments include long-term rodent toxicity/carcinogenicity bioassays and shorter duration studies that focus on reproductive and developmental toxicology endpoints. These experiments are the first step of a broader risk assessment process to determine the magnitude of human risk associated with exposure to a test substance. Statistical issues that arise in these studies include (i) selection of the number, magnitude, and spacing of doses; (ii) use of statistical methodology that adjusts for potentially confounding factors such as survival, body weight, and litter effects; (iii) multiple comparison adjustments for the large number of variables evaluated; (iv) use of historical control data; and (v) development of appropriate statistical methodology to permit extrapolation of experimental results from high to low doses and from species to species. Keywords: carcinogenicity bioassays; developmental toxicology; risk assessment; dose selection; litter effects; extrapolation; covariates; simultaneous inference
Cocaine and Methamphetamine Addiction: Treatment, Recovery and Relapse Prevention, by Arnold Washton and Joan Ellen Zweben

In Cocaine and Methamphetamine Addiction: Treatment, Recovery and Relapse Prevention, Washton and Zweben revise Washton's 1989 work on cocaine addiction by addressing methamphetamine, as well. This...
STRUCTURED STRATEGY INSTRUCTION: INVESTIGATING AN INTERVENTION FOR IMPROVING SIXTH-GRADERS' READING COMPREHENSION

Little empirical evidence supporting various instructional strategies for teaching reading comprehension exists. Because difficulties with comprehension are intensified as students reach the intermediate grades, it is essential that middle school educators provide research-based instruction. This study examined the effectiveness of the Directed Reading-Thinking Activity (Stauffer, 1969), the Pre-reading Plan (Langer & Nicholich, 1981), and graphic organizers (Barron, 1969), three strategies popular among middle school teachers. Six teachers participated in the two-group design, pretest/posttest study; over seven weeks, three teachers instructed their sixth-grade students using lessons constructed with the strategies (n = 103). Results indicate a significant difference (p < .05) between the groups according to an informal procedure; a formal test indicated no significant difference. Implications of the findings and suggestions for replication and extension of the design are included.
Assessing normality and equivariance in small multigroup samples

A common design in biological and toxicological experimentation consists of k groups, each of sample size n. Statistical procedures for the analysis of resulting data often assume normality and equal within group variance. We examined statistical procedures based on probabilityplotting techniques for assessing these assumptions through computer simulations.. To obtain critical values, we generated 10,000 homogeneous normal samples for k=2, 3 and 4, and for n=4 to 12. Power comparisons were made using 1,000 samples each from a variety of non-normal and heterogeneous variance situations. Our two main findings were as follows: (1) None of the procedures studied was uniformly best, but several (Shapiro-Wilk W, R2 1 and z2 were generally superior. (2) Critical values for some of the "standard" tests need to be adjusted for the multigroup case.
Multifractality of the harmonic measure on fractal aggregates, and extended self-similarity

Abstract We show that DLA follows a surprising new scaling rule. It expresses that the screened region, in which the harmonic measure is tiny, increases more than proportionately as the cluster grows. This scaling rule also gives indirect evidence that the harmonic measure of lattice DLA follows a hyperbolic probability distribution of exponent equal to 1. This distribution predicts that sample moments behave erratically, hence explains why the common restricted multifractal formalism fails to apply to DLA.
Adaptive control of a robot arm using driver programs

Most successful state-of-the-art robotic manipulators have the characteristic of producing precise, fast, smooth and reproducible movements. Their drawback is that they tend to have a limited repertoire which can only be extended by costly inverse kinematics calculations or direct teach-in sessions. The goal of our project is to develop a flexible open world robot, which adapts to its task and environment progressively and in an iterative manner. It begins carefully and slowly, with small jagged movements, but, after repetition, reaches an acceptable level of smoothness and execution speed. It can be placed in new surroundings with new task definitions, requiring only a further practice time before becoming expert. Similarities from other sub-tasks are recognized and may be transferred to the new domains. The basic constituents of the adaptive robot are simple iterative inverse kinematics and driver programs. In this paper the idea of driver programs for robot arm control is introduced and their properties investigated.
Investigation of the transport and deposition of fullerene (C60) nanoparticles in quartz sands under varying flow conditions

A coupled experimental and mathematical modeling investigation was undertaken to explore nanoscale fullerene aggregate (nC60) transport and deposition in water-saturated porous media. Column experiments were conducted with four different size fractions of Ottawa sand at two pore-water velocities. A mathematical model that incorporates nonequilibrium attachment kinetics and a maximum retention capacity was used to simulate experimental nC60 effluent breakthrough curves and deposition profiles. Fitted maximum retention capacities (S(max)), which ranged from 0.44 to 13.99 microg/g, are found to be correlated to normalized mass flux. The developed correlation provides a means to estimate S(max) as a function of flow velocity, nanoparticle size, and mean grain size of the porous medium. Collision efficiency factors, estimated from fitted attachment rate coefficients, are relatively constant (approximately 0.14) over the range of conditions considered. These fitted values, however, are more than 1 order of magnitude larger than the theoretical collision efficiency factor computed from Derjaguin-Landau-Verwey-Overbeek (DLVO) theory (0.009). Data analyses suggest that neither physical straining nor attraction to the secondary minimum is responsible for this discrepancy. Patch-wise surface charge heterogeneity on the sand grains is shown to be the likely contributor to the observed deviations from classical DLVO theory. These findings indicate that modifications to clean-bed filtration theory and consideration of surface heterogeneity are necessary to accurately predict nC60 transport behavior in saturated porous media.
Fluorination of single-wall carbon nanotubes

Abstract Purified single-wall carbon nanotubes (SWNTs) were fluorinated at several different temperatures. Product stoichiometries were determined and electron microscopy was used to verify whether or not the fluorination was destructive of the tubes. SWNTs fluorinated at three different temperatures were then defluorinated using hydrazine. Raman spectroscopy and resistance measurements were utilized to verify whether or not the products of the defluorination were in fact SWNTs. It has been determined that the bulk of the SWNTs survive the fluorination process at temperatures up to 325°C and that hydrazine can be employed as an effective defluorinating agent to regenerate the unfluorinated starting material.
Optimal fields for integral equations

Abstract The theory of optimal fields is developed for optimal control problems in which the state variables are determined by integral equations. The Hilbert integral is considered and the Hamilton-Jacobi equations are derived. The results obtained contain two maximum principles as special cases; one reflecting the special character of field theory and one corresponding to the results previously obtained by use of variations.
Competitive deposition oftrans-12- andcis-9-octadecenoates into egg yolk lipids

The deposition oftrans-12-octadecenoate-12(13)-3H (12t-18∶1-3H) was compared tocis-9-octadecenoate-10-14C (9c-18∶1-14C) in the major egg yolk neutral lipids and phospholipids.trans-12-Octadecenoate was preferentially incorporated into cholesteryl esters (CE), phosphatidylcholines (PC), and phosphatidylethanolamines (PE) but was discriminated against in triglycerides (TG). Isotopic ratios indicate that 5.9 and 5.6 times more 12t-18∶1-3H than 9c-18∶1-14C was esterified at the 1-acyl position of PE and PC, respectively. The combined 1- and 3-acyl positions of TG and the 2-acyl position of TG, PE and PC were each preferentially esterified with 9c-18∶1-14C.
Yahoo! as an ontology: using Yahoo! categories to describe documents

We suggest that one (or a collection) of names of Yahoo! (or any other WWW indexer's) categories can be used to describe the content of a document. Such categories offer a standardized and universal way for referring to or describing the nature of real world objects, activities, documents and so on, and may be used (we suggest) to semantically characterize the content of documents. WWW indices, like Yahoo! provide a huge hierarchy of categories (topics) that touch every aspect of human endeavors. Such topics can be used as descriptors, similarly to the way librarians use for example, the Library of Congress cataloging system to annotate and categorize books.In the course of investigating this idea, we address the problem of automatic categorization of webpages in the Yahoo! directory. We use Telltale as our classifier; Telltale uses n-grams to compute the similarity between documents. We experiment with various types of descriptions for the Yahoo! categories and the webpages to be categorized. Our findings suggest that the best results occur when using the very brief descriptions of the Yahoo! categorized entries; these brief descriptions are provided either by the entries' submitters or by the Yahoo! human indexers and accompany most Yahoo!-indexed entries.
438 EXCRETION PATTERNS OF 6-HYDROXIMELAT ON IN IN PUEERTAL AND PEEPUBERTAL CHILDREN

Pineal secretion of melatonin is hypothesized to suppress gonadal development in both experimental animals and man. A recent report by Silman et al demonstrated a marked decrease in blood melatonin in males but not in females at the time of the onset of puberty. We have developed a gas chromatographic-mass spectrometric method for urinary 6-hydroxymelatonin, which is the major metabolite of melatonin excreted by man. We have previously shown that normal adults exhibit a circadian pattern for urinary excretion of 6-hydroxymelatonin with a total excretion ranging to 6-18 μg/24 hrs and with greater than 80% of the total excretion being from 12 midnight to noon. The urinary excretion of 6-hydroxymelatonin appears to reflect the pineal secretion of melatonin. We measured the circadian excretion of 6-hydroxymelatonin in 24 normal children ages 3-15 years to determine whether the pattern or amount of 6-hydroxymelatonin excreted varies with age and pubertal development and specifically whether a decrease in excretion might accompany the onset of puberty. The normal children showed the same circadian rhythm as adults with the range of total secretion of 8 to 20 μg/24 hours. Our data suggests that the pineal gland in children secretes adult levels of melatonin beginning at the earliest ages studied.
Implications of sustained suppression of gastric acid secretion

The implications of profound and sustained suppression of acid secretion are of increasing concern. Short-term inhibition of acid secretion by H2-receptor blockade or proton pump inhibition alters the gastric luminal flora and increases the risk of nosocomial pneumonia in critically ill patients who are receiving prophylaxis for stress gastritis. Long-term suppression alters gut flora, carcinogen levels in the gastric lumen, and the hormonal milieu, leading to proliferative changes in the fundic mucosa. Previous reports have noted a significant incidence of gastric malignancies in the achlorhydric environment of atrophic gastritis and pernicious anemia. Concern has also been expressed regarding the possibility of gastric neoplasia that arises after vagotomy and distal gastrectomy. The exact risk of gastric epithelial and endocrine hyperplasia or neoplasia in patients receiving potent antisecretory agents is not yet known, but such risks cannot be dismissed until long-term follow-up studies are available. The relationship between sustained suppression of acid secretion and the proliferation of epithelial and endocrine elements may provide insight into processes that regulate replication and growth of cells in the gastric mucosa.
Chronophin, a novel HAD-type serine protein phosphatase, regulates cofilin-dependent actin dynamics

Cofilin is a key regulator of actin cytoskeletal dynamics whose activity is controlled by phosphorylation of a single serine residue. We report the biochemical isolation of chronophin (CIN), a unique cofilin-activating phosphatase of the haloacid dehalogenase (HAD) superfamily. CIN directly dephosphorylates cofilin with high specificity and colocalizes with cofilin in motile and dividing cells. Loss of CIN activity blocks phosphocycling of cofilin, stabilizes F-actin structures and causes massive cell division defects. Our findings identify a physiological phospho-serine protein substrate for a mammalian HAD-type phosphatase and demonstrate that CIN is an important novel regulator of cofilin-mediated actin reorganization.
Characterization of edge effects in cellular materials

Cellular solids constitute a unique class of materials possessing a high stiffness to weight ratio. Due to the high level of porosity in these materials (70 to 99.7%) one must utilize special testing considerations in order to obtain accurate results. One of these items has been referred to as edge effects and stems from the large scale macrostructure of cellular materials. This results in a dramatic decrease in the mechanical properties when testing small specimens having a large cell size. A reticulated vitreous carbon was used to characterize these effects for both elastic modulus and flexural strength measurements. It was observed that a critical specimen to cell size ratio is required to overcome these effects and achieve accurate results. A simple model is presented to help in predicting these edge effects.
Responsive evaluation of competency-based public health preparedness training programs.

OBJECTIVES: To describe how the Michigan Center for Public Health Preparedness (MI-CPHP) responded to the challenge and urgency in delivering competency-based preparedness training and documenting its impact utilizing a responsive evaluation approach. METHODS: Pretest-posttest evaluation designs were implemented when feasible to document the impact of training activities on knowledge and competency gains. The development of evaluation instruments is described with a focus on being responsive to the specific goals of each training activity. A randomized experimental design was used to examine the effects of taking a pretest for one of the training events. RESULTS: The analyses noted statistically significant improvements for every comprehensive training event in key content knowledge and self-rated competencies. The impact of taking a pretest revealed a modest, but statistically significant, effect on the self-rated competencies and a nonsignificant effect on the content knowledge scores. CONCLUSIONS: A summary of the results and their implications is followed by a discussion about taking a responsive approach to evaluating the training activities of the MI-CPHP. The challenge of evaluating the impact of knowledge-focused training activities on the development of performance competencies was also reviewed. Language: en
Introducing an Irrigation Scheme to a Regional Climate Model: A Case Study over West Africa

This article presents a new irrigation scheme and biome to the dynamic vegetation model, Integrated Biosphere Simulator (IBIS), coupled to version 3 of the Regional Climate Model (RegCM3-IBIS). The new land cover allows for only the plant functional type (crop) to exist in an irrigated grid cell. Irrigation water (i.e., negative runoff) is applied until the soil root zone reaches relative field capacity. The new scheme allows for irrigation scheduling (i.e., when to apply water) and for the user to determine the crop to be grown. Initial simulations show a large sensitivity of the scheme to soil texture types, how the water is applied, and the climatic conditions over the region. Application of the new scheme is tested over West Africa, specifically Mali and Niger, to simulate the potential irrigation of the Niger River. A realistic representation of irrigation of the Niger River is performed by constraining the land irrigated by the annual flow of the Niger River and the amount of arable land in the region as reported by the Food and Agriculture Organization of the United Nations (FAO). A 30-yr simulation including irrigated cropland is compared to a 30-yr simulation that is identical but with no irrigation of the Niger. Results indicate a significant greening of the irrigated land as evapotranspiration over the crop fields largely increases—mostly via increases in transpiration from plant growth. The increase in the evapotranspiration, or latent heat flux (by 65‐150Wm 22 ), causes a significant decreasein thesensibleheatfluxwhilesurfacetemperatures coolon averagebynearly58C. Thiscoolingisfelt downwind, where averagedailytemperaturesoutsidetheirrigationarereducedby 0.58‐1.08C. Likewise,large increases in 2-m specific humidity are experienced across the irrigated cropland (on the order of 5gkg 21 ) but also extend farther north and east, reflecting the prevailing surface southwesterlies. Changes (decreases) in rainfall are found only over the irrigated lands of west Mali. The decrease in rainfall can be explained by the largesurfacecoolingandcollapseof theboundarylayer(by approximately 500m).Both leadtoareductionin the triggering of convection as the convective inhibition, or negative buoyant energy, is never breached. Nevertheless, the new scheme and land cover allows for a novel line of research that can accurately reflect the effectsofirrigationonclimateandthesurroundingenvironmentusingadynamicvegetationmodelcoupledto a regional climate model.
Rate of arterial occlusion in patients with acute ischemic stroke

Abstract Objective: Computed tomographic angiography (CTA) was invented more than 20 years ago, but only gained acceptance recently, thanks to advancements in the computer technology. It can demonstrate areas of arterial stenosis or occlusion with accuracy nearly that of digital subtraction angiography (DSA). It is also able to clearly illustrate calcification, which is more difficult to define on magnetic resonance angiography and is not clearly depicted on DSA. Methods: Our retrospective study attempted to clarify the rate of occlusion or stenosis in the patients with acute ischemic stroke. Results: Over the period of 7 months, 93 consecutive patients were admitted with acute ischemic stroke. Fifty-six patients underwent CTA and were included in this study. Most of the patients were admitted after 6 hours following onset of symptoms. There were 28 men and 28 women, and 80.4% of the cohort was of African-American origin. The majority of strokes were attributed to small-vessel disease (25/56). The rest of...
Radio frequency interference suppression for landmine detection by quadrupole resonance

The quadrupole resonance (QR) technology can be used as a confirming sensor for buried plastic landmine detection by detecting the explosives within the mine. We focus herein on the detection of TNT mines via the QR sensor. Since the frequency of the QR signal is located within the AM radio frequency band, the QR signal can be corrupted by strong radio frequency interferences (RFIs). Hence to detect the very weak QR signal, RFI mitigation is essential. Reference antennas, which receive RFIs only, can be used together with the main antenna, which receives both the QR signal and the RFIs, for RFI mitigation. The RFIs are usually colored both spatially and temporally, and hence exploiting only the spatial diversity of the antenna array may not give the best performance. We exploit herein both the spatial and temporal correlations of the RFIs to improve the TNT detection performance.
Assessment of diaphragmatic stressors as risk factors for symptomatic failure of laparoscopic nissen fundoplication

An important limitation of antireflux surgery is a 5%-10% failure rate. We investigated the correlation between various diaphragm stressors and failure of antireflux surgery. Forty-one study cases who underwent a reoperative antireflux operation from 1997 to 2001 and 50 control patients who had undergone a successful laparoscopic Nissen fundoplication during the same period without clinical or symptomatic evidence of failure were randomly selected for comparison. A retrospective analysis was conducted utilizing a standardized diaphragm stressor questionnaire, addressing the period between the primary and secondary operation. Stressors considered in the study included height, body mass index (BMI), postoperative gagging, vomiting, weight lifting (greater than 100 pounds), coughing, hiccuping, motion sickness, retching, belching, antidepressant use, smoking, preoperative grade of esophagitis, size of hiatal hernia, lower esophageal sphincter pressure, esophageal body pressures, and preoperative response to proton pump inhibitors. Of the potential stressors investigated, the following were significantly associated with surgical failure after adjusting for other variables through multivariate analysis: gagging (P = 0.005), belching (P = 0.02), and hernia size greater than 3 cm (P = 0.04; Table 1). Other potential risk factors show trends as obvious in Fig. 2. Vomiting was significant (P = 0.01) in the earlier models but lost significance when logistic regression was applied. Patients with postoperative gagging and an intraoperative hiatal hernia (greater than 3 cm) have a poorer outcome, whereas patients with postoperative belching have a better long-term outcome.
Genetic analysis of the mitotic transmission of minichromosomes

The fidelity of the mitotic transmission of minichromosomes in S. cerevisiae is monitored by a novel visual assay that allows one to detect changes in plasmid copy number in individual mitotic divisions. This assay is used to investigate the mitotic transmission of a plasmid containing a putative yeast origin of replication (ARS 1) and a centromere (CEN3). The rate of improper segregation for the minichromosome is 200-fold higher than observed for a normal chromosome. However, the replication of the minichromosome is stringently controlled; it overreplicates less than once per one thousand mitotic divisions. We also use this assay to isolate and characterize mutations in ARS 1 and CEN3. The mutations in ARS 1 define a new domain required for its optimal activity, and the mutations in CEN3 suggest that the integrity of element II is not essential for centromere function. Finally, the phenotypes of the mutations in ARS 1 and CEN3 are consistent with their function in replication and segregation, respectively.
A Robust Nonlinear Tracking Control Approach for Multi-Body Flexible Dynamic Systems

In this research, a multi-input multi-output (MIMO) integral continuous sliding mode design approach is proposed to achieve multi-objective robust tracking control for nonlinear dynamic systems. Instead of employing the equivalent control and switching control concepts in conventional variable structure methodology, here we develop a new design procedure using continuous control law with a tunable order of state feedback. As a result, the chattering phenomenon can be completely eliminated and the control sensitivity can be adjusted using the proposed sensitivity parameter. This design procedure can be applied to a general class of mechanical systems. The performance of the controller is verified using a series of simulation studies on flexible rotating beam and robotic manipulator.Copyright © 2006 by ASME
The lifespan of osteoclasts: experimental studies using the giant granule cytoplasmic marker characteristic of beige mice.

Abstract Osteoclasts are large multlnucleated skeletal cells that form by fusion of bloodborne mononuclear precursors. Fusion with mononuclear precursors occurs throughout life, and survival of Osteoclasts is believed to be dependent upon continued replenishment by fusion. This study examined osteoclast lifespan, defined as maximal survival without fusion, in normal mice irradiated to eliminate host stem cells and rescued with stem cells from beige (bg) mice whose osteoclasts have a distinctive phenotype. Osteoclasts of donor phenotype appeared during the second week and progressively increased so that by the sixth week no osteoclasts of host phenotype were present. Radiation alone did not produce any change in osteoclast phenotype. These data are interpreted to indicate that the maximal survival of osteoclasts without fusion of precursors is less than 6 weeks.
Probing gas-phase collisional energy transfer with picosecond laser spectroscopy

Effects of gas-phase collisions on active optical sensing and use of picosecond laser spectroscopy for their characterization are reviewed. Additionally, novel time-resolved approaches to reduce collisional sensitivity and to exploit species-dependent collision rates are discussed.
The Significance of Teachers’ Marks

It may be assumed, broadly speaking, that the teacher's mark is a function of the inherent ability of the student. If this be not true, we may as well abandon this line of research at once. Other things being equal, it is to be presumed that the brighter the stu dent and the more diligent his application the higher his mark will be. But other things are not equal. Primarily teachers' judg ments are not equal ; teachers are not automatons. Even the same teacher will not render precisely the same judgment of the same work on successive days, and many factors may enter into the conditions to modify or even to distort the decision regarding the precise mark in each individual case. These facts have been demon strated again and again by the work of many investigators. Starch has summarized much of this work and has drawn the conclusion that marks vary "enormously from teacher to teacher and from school to school."26
The Importance of Language in Students' Reasoning About Heat in Thermodynamic Processes

Researchers believe that the way that students talk, specifically the language that they use, can offer a window into their reasoning processes. Yet the connection between what students are saying and what they are actually thinking can be ambiguous. We present the results of an exploratory interview study with 10 participants, designed to investigate the role of language in university physics students' reasoning about heat in thermodynamic processes. The study revealed two key findings: (1) students' approaches to solving certain heat-related problems are related to the way in which they explicitly define the word ‘heat’ and (2) students' tendency to reason with heat as a state function in inappropriate contexts appears to be connected to a model of heat implicitly encoded in language. This model represents heat or heat energy/thermal energy as a substance that moves from one location to another. In this model, students talk about thermodynamic systems as ‘containers' of heat, and temperature is a measur...
Optimization of 4H-SiC power Schottky Barrier Diodes

Silicon Carbide (SiC) is among the most promising semiconductor for high-voltage and high-temperature power electronics switching applications. A careful analysis of the current state-of-the-art commercial 4H-SiC power Schottky Barrier Diodes (SBDs) shows that these devices are operated well below their true avalanche breakdown potential. It is found that the breakdown voltage ratings of these devices are smaller nearly by a factor of 2 due to increased leakage current caused by drift-region punch-through. A simple analysis is presented to determine the de-rating factor of SiC power SBDs using the information provided in the manufacturer's data sheets. It is recommended that further improvement in material growth and manufacturing technologies offer significant promise in developing robust, low-cost, and high-performance SiC power switching devices.
On J. H. C. Whitehead's aspherical question I

A connected, finite two-dimensional CW-complex with fundamental group isomorphic toG is called a [G, 2] f -complex. LetL⊲G be a normal subgroup ofG. L has weightk if and only ifk is the smallest integer such that there exists {l1,…,lk}⊆L such thatL is the normal closure inG of {l1,…,lk}. We prove that a [G, 2] f -complexX may be embedded as a subcomplex of an aspherical complexY=X∪{e 1 2 ,…,e k 2 } if and only ifG has a normal subgroupL of weightk such thatH=G/L is at most two-dimensional and defG=defH+k. Also, ifX is anon-aspherical [G, 2] f -subcomplex of an aspherical 2-complex, then there exists a non-trivial superperfect normal subgroupP such thatG/P has cohomological dimension ≤2. In this case, any torsion inG must be inP.
Long-term effects on the nasopharyngeal flora of children following antimicrobial therapy of acute otitis media with cefdinir or amoxycillin-clavulanate.

The effect on the nasopharyngeal bacterial flora of 10 days of amoxycillin-clavulanate or cefdinir antimicrobial therapy was studied in 50 children with acute otitis media. Before therapy, 17 potential pathogens (Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis) were isolated from the nasopharynx of 14 (56 %) of those treated with amoxycillin-clavulanate, and 20 potential pathogens were recovered from 15 (60 %) of those treated with cefdinir. Following therapy, at days 12–15, the number of potential pathogens was reduced to a similar extent with both therapies, to three in those treated with amoxycillin-clavulanate and two in those treated with cefdinir. However, the number of potential pathogens rebounded faster in those treated with amoxycillin-clavulanate as compared with cefdinir in the two subsequent specimens taken at days 30–35 and 60–65 (12 and 18 in the amoxycillin-clavulanate group, and six and nine in the cefdinir group, P < 0.01 and P < 0.001, respectively). Differences between the groups were also noted in the recovery of organisms with interfering capability. Immediately following amoxycillin-clavulanate therapy, the number of interfering organisms declined from 54 to 13, while following cefdinir treatment their number was reduced from 59 to 39 (P < 0.001). The differences between the two therapy groups persisted in the two later specimens taken at days 30–35 and 60–65 (25 and 38 in the amoxycillin-clavulanate group, and 52 and 51 in the cefdinir group, P < 0.001 and P < 0.05, respectively). This study illustrates the potential beneficial effect of using a narrow-spectrum antimicrobial that selectively spares the interfering organisms while eliminating pathogens. The benefit of such therapy is the prevention of reacquisition of pathogenic bacteria in the nasopharynx. In contrast, utilization of a broad-spectrum antimicrobial is associated with prolonged absence of inhibitory organisms and rapid recolonization with pathogens.
Calling Dirty Harry a liar: a critique of displacement theories of popular criminology

Displacement analyses of popular film purport that Hollywood filmmakers dissemble the morals or implications of their stories in ways that can mislead audiences and gain hegemony. A review of the reception and scholarly analysis of Dirty Harry movies shows that such displacement theories can become influential in the absence of evidence for their central claims. Where a scholarly consensus has it that the successful sequel Magnum Force (1973) was meant to placate liberal critics and affirm its rightist message in a covert manner, accounts of its authors suggest a straightforward anti-liberalism that links bureaucracy to fascism. This paper concludes by suggesting a higher standard of evidence for theories of filmmaker intent, which focuses on industry routines and generic patterns. Where an influential theory of film has led scholars to dismiss many popular films as lies, the study of patterns and production and genre storytelling offers better potential for understanding the origins and politics – right-...
Laboratory double layers with no external fields

Abstract It is shown that the formation of double layers in a triple plasma device does not require an externally applied electric field across the plasma boundaries.
Symmetric crossbar arbiters for VLSI communication switches

The design and implementation of symmetric crossbar arbiters are addressed. Several arbiter designs are compared based on simulations of a multistage interconnection network. These simulations demonstrate the influence of the switch arbitration policy on network throughput, average latency, and worst-case latency. It is shown that some natural designs result in poor system performance and/or slow implementations. Two efficient arbiter implementations are proposed. Based on network simulations, VLSI implementation, and circuit simulation, it is shown that these arbiters achieve nearly optimal system performance without becoming the critical path that limits the system clock. >
Using gamification to motivate children to complete empirical studies in lab environments

In this paper, we describe the challenges we encountered and solutions we developed while collecting mobile touch and gesture interaction data in laboratory conditions from children ages 5 to 7 years old. We identify several challenges of conducting empirical studies with young children, including study length, motivation, and environment. We then propose and validate techniques for designing study protocols for this age group, focusing on the use of gamification components to better engage children in laboratory studies. The use of gamification increased our study task completion rates from 73% to 97%. This research contributes a better understanding of how to design study protocols for young children when lab studies are needed or preferred. Research with younger age groups alongside older children, adults, and special populations can lead to more sound guidelines for universal usability of mobile applications.
Corkscrew point spread function for far-field three-dimensional nanoscale localization of pointlike objects

We describe the corkscrew point spread function (PSF), which can localize objects in three dimensions throughout a 3.2μm depth of field with nanometer precision. The corkscrew PSF rotates as a function of the axial (z) position of an emitter. Fisher information calculations show that the corkscrew PSF can achieve nanometer localization precision with limited numbers of photons. We demonstrate three-dimensional super-resolution microscopy with the corkscrew PSF by imaging beads on the surface of a triangular polydimethylsiloxane (PDMS) grating. With 99,000 photons detected, the corkscrew PSF achieves a localization precision of 2.7nm in x, 2.1nm in y, and 5.7nm in z.