cssi/SciSciGPT-SciSciNet huggingface dataset:
Applications of semi-implicit Fourier-spectral method to phase field equations

Abstract An efficient and accurate numerical method is implemented for solving the time-dependent Ginzburg—Landau equation and the Cahn—Hilliard equation. The time variable is discretized by using semi-implicit schemes which allow much larger time step sizes than explicit schemes; the space variables are discretized by using a Fourier-spectral method whose convergence rate is exponential in contrast to second order by a usual finite-difference method. We have applied our method to predict the equilibrium profiles of an order parameter across a stationary planar interface and the velocity of a moving interface by solving the time-dependent Ginzburg—Landau equation, and compared the accuracy and efficiency of our results with those obtained by others. We demonstrate that, for a specified accuracy of 0.5%, the speedup of using semi-implicit Fourier-spectral method, when compared with the explicit finite-difference schemes, is at least two orders of magnitude in two dimensions, and close to three orders of magnitude in three dimensions. The method is shown to be particularly powerful for systems in which the morphologies and microstructures are dominated by long-range elastic interactions.
Postpartum Depression in Mothers of Infants in Neonatal Intensive Care Unit: Risk Factors and Management Strategies

Objective The aim of this study is to assess incidence, risk factors, and management strategies for Postpartum depression (PPD) in mothers of neonatal intensive care unit (NICU) infants. Study Design A total of 131 mothers completed the study assessment tool (Edinburgh Postnatal Depression Scale with additional questions). Score of 10 or above was considered to indicate risk for PPD (subclinical depression). Risk factors were examined with particular emphasis on length of stay (LOS). Results Approximately 19.1% of mothers experienced (subclinical) PPD. Depression during current and previous pregnancy, and problems with current delivery were strong predicting risk factors for PPD. As the LOS increased beyond 2 weeks, the odds of PPD risks initially increased, then leveled off, and then decreased after 31 days. Conclusion We recommend that the mothers of NICU infants be routinely screened for PPD and aggressively treated.
The relation between invertebrate drift and two primary controls, discharge and benthic densities, in a large regulated river

Summary Invertebrate drift is a fundamental process in streams and rivers. Studies from laboratory experiments and small streams have identified numerous extrinsic (e.g. discharge, light intensity, water quality) and intrinsic factors (invertebrate life stage, benthic density, behaviour) that govern invertebrate drift concentrations (# m−3), but the factors that govern invertebrate drift in larger rivers remain poorly understood. For example, while large increases or decreases in discharge can lead to large increases in invertebrate drift, the role of smaller, incremental changes in discharge is poorly described. In addition, while we might expect invertebrate drift concentrations to be proportional to benthic densities (# m−2), the benthic–drift relation has not been rigorously evaluated. Here, we develop a framework for modelling invertebrate drift that is derived from sediment transport studies. We use this framework to guide the analysis of high-resolution data sets of benthic density and drift concentration for four important invertebrate taxa from the Colorado River downstream of Glen Canyon Dam (mean daily discharge 325 m3 s−1) that were collected over 18 months and include multiple observations within days. Ramping of regulated flows on this river segment provides an experimental treatment that is repeated daily and allowed us to describe the functional relations between invertebrate drift and two primary controls, discharge and benthic densities. Twofold daily variation in discharge resulted in a >10-fold increase in drift concentrations of benthic invertebrates associated with pools and detritus (i.e. Gammarus lacustris and Potamopyrgus antipodarum). In contrast, drift concentrations of sessile blackfly larvae (Simuliium arcticum), which are associated with high-velocity cobble microhabitats, decreased by over 80% as discharge doubled. Drift concentrations of Chironomidae increased proportional to discharge. Drift of all four taxa was positively related to benthic density. Drift concentrations of Gammarus, Potamopyrgus and Chironomidae were proportional to benthic density. Drift concentrations of Simulium were positively related to benthic density, but the benthic–drift relation was less than proportional (i.e. a doubling of benthic density only led to a 40% increase in drift concentrations). Our study demonstrates that invertebrate drift concentrations in the Colorado River are jointly controlled by discharge and benthic densities, but these controls operate at different timescales. Twofold daily variation in discharge associated with hydropeaking was the primary control on within-day variation in invertebrate drift concentrations. In contrast, benthic density, which varied 10- to 1000-fold among sampling dates, depending on the taxa, was the primary control on invertebrate drift concentrations over longer timescales (weeks to months).
Activity of the multitargeted antifolate LY231514 in the human tumor cloning assay.

Purpose: This study was performed to evaluate the activity of the multitargeted antifolate (MTA or LY231514) against a broad range of human tumors taken directly from patients. Materials and methods: Human tumor colony-forming units were treated with MTA at concentrations of 0.1, 1.0, and 10 μg/ml in 1-h exposure studies. The responses of a limited number of specimens were also evaluated concurrently in 1-h exposures to cisplatin, fluorouracil, irinotecan, and/or paclitaxel. Results: Of 358 specimens plated in the 1-h exposure studies, 148 (41%) were evaluable. Overall, responses were observed in 3% of specimens (4/144) at 0.1 μg/ml, 11% (17/148) at 1.0 μg/ml, and 23% (33/141) at 10 μg/ml. In this range of concentrations achievable clinically, there was a significant concentration-response relationship. At 10 μg/ml in the 1-h exposure studies, the response rate in colorectal cancer specimens was 32% (9/28), and the response rate in non-small-cell lung cancer was 25% (6/24). Responses were also observed in several chemoresistant tumors, including renal cell carcinoma, hepatocellular carcinoma, mesothelioma, and pancreatic carcinoma. The activity of MTA was not completely cross-resistant with that of cisplatin, fluorouracil, irinotecan, and paclitaxel. Conclusions: MTA demonstrated in vitro activity against a spectrum of tumors, including several tumors generally considered chemoresistant.
De novo sequencing of tryptic peptides derived from Deinococcus radiodurans ribosomal proteins using 157 nm photodissociation MALDI TOF/TOF mass spectrometry

Vacuum ultraviolet photodissociation of peptide ions in a matrix assisted laser desorption ionization (MALDI) tandem time-of-flight (TOF) mass spectrometer is used to characterize peptide mixtures derived from Deinococcus radiodurans ribosomal proteins. Tryptic peptides from 52 proteins were separated by reverse-phase liquid chromatography and spotted onto a MALDI plate. From 192 sample spots, 492 peptide ions were isolated, fragmented by both photodissociation and postsource decay (PSD), and then de novo sequenced. Three-hundred seventy-two peptides yielded sequences with 5 or more amino acids. Homology searches of these sequences against the whole bacterial proteome identified 49 ribosomal proteins, 45 of which matched with two or more peptides. Peptide de novo sequencing identified slightly more proteins than conventional database searches using Mascot and was particularly advantageous in identifying unexpected peptide modifications. In the present analysis, 52 peptide modifications were identified by de novo sequencing, most of which were not recognized by database searches.
The impacts of hospital alliance membership, alliance size, and repealing certificate of need regulation, on the cost efficiency of non‐profit hospitals

This paper investigates how alliance membership, size of the alliance, membership in multiple organizations, repealing certificate of need (CON) regulation for acute care facilities, and other factors, impacts hospital cost efficiency. Using a 1996–1999 panel of 144 urban US Midwestern hospitals, empirical results show that repealing state CON programs, signing more HMO and PPO contracts, and membership in only an alliance, helped to enhance cost efficiency. Membership in an additional organization (network, system) did not help enhance hospital cost efficiency. Membership in a larger size alliance (more hospitals in the alliance) contributed to an improvement in cost efficiency. Copyright © 2010 John Wiley & Sons, Ltd.
Turning potatoes into wine on Long Island's North Fork

This study explores the perceived negative and positive impact of rapid change on an unusual and historical strip of land as it shifts from rural in actuality—in 1940 there were 73 potato farms, to ‘rural’ in name only—in 2004 six remain. It ethnographically profiles the farmers who choose to stay, some evolving as entrepreneurial showmen constructing corn mazes far more profitable than corn, others clinging to charming if quaint methods of agriculture, while others passionately transition to organic, biodynamic, and artisanal product. Since 1973, when the first vinifera vines were planted, the majority of new farmers choose to grow grapes, producing some excellent wines. The area is now also known as “Wine Country.” Because of its close proximity to New York City and the “Hamptons”, an extremely fashionable and wealthy area that borders the Atlantic Ocean, the North Fork of Long Island is beginning to thrive as a culinary destination for day trippers and weekenders. Pleased, of course, to prosper, landowners are also eager to hold onto the cherished identity of “The Unhamptons,” a euphemism for quiet, laid back, and authentic—a somewhat playful slur directed at its wealthier, glitzier cousins to the South. This is becoming a challenge as developers scrape and divide farmland they once ignored, and tract housing poses a serious threat to the area and its bucolic charm.
Comparison of human induced pluripotent stem-cell derived cardiomyocytes with human mesenchymal stem cells following acute myocardial infarction.

Introduction Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have recently been shown to express key cardiac proteins and improve in vivo cardiac function when administered following myocardial infarction. However, the efficacy of hiPSC-derived cell therapies, in direct comparison to current, well-established stem cell-based therapies, is yet to be elucidated. The goal of the current study was to compare the therapeutic efficacy of human mesenchymal stem cells (hMSCs) with hiPSC-CMs in mitigating myocardial infarction (MI).
A Comparison of On-Site Nutrient and Energy Recycling Technologies in Algal Oil Production

Abstract Research on biofuel production pathways from algae continues because among other potential advantages they avoid key consequential effects of terrestrial oil crops, such as competition for cropland. However, the economics, energetic balance, and climate change emissions from algal biofuels pathways do not always show great potential, due in part to high fertilizer demand. Nutrient recycling from algal biomass residue is likely to be essential for reducing the environmental impacts and cost associated with algae-derived fuels. After a review of available technologies, anaerobic digestion (AD) and hydrothermal liquefaction (HTL) were selected and compared on their nutrient recycling and energy recovery potential for lipid-extracted algal biomass using the microalgae strain Scenedesmus dimorphus. For 1 kg (dry weight) of algae cultivated in an open raceway pond, 40.7 g N and 3.8 g P can be recycled through AD, while 26.0 g N and 6.8 g P can be recycled through HTL. In terms of energy production, 2.49 MJ heat and 2.61 MJ electricity are generated from AD biogas combustion to meet production system demands, while 3.30 MJ heat and 0.95 MJ electricity from HTL products are generated and used within the production system. Assuming recycled nutrient products from AD or HTL technologies displace demand for synthetic fertilizers, and energy products displace natural gas and electricity, the life cycle greenhouse gas reduction achieved by adding AD to the simulated algal oil production system is between 622 and 808 g carbon dioxide equivalent (CO2e)/kg biomass depending on substitution assumptions, while the life cycle GHG reduction achieved by HTL is between 513 and 535 g CO2e/kg biomass depending on substitution assumptions. Based on the effectiveness of nutrient recycling and energy recovery, as well as technology maturity, AD appears to perform better than HTL as a nutrient and energy recycling technology in algae oil production systems.
Low temperature magnetic properties and molecular structure of Cu(2,2′-bipyridine)2(NCS)2

Abstract The temperature and field dependence of the magnetic susceptibility of Cu(2,2′-bipyridine) 2 (NCS) 2 have been determined over the range 2–100 K using the Faraday method. The magnetic results in conjunction with IR spectra are inconsistent with a previous formulation of the compound as a thiocyanate bridged dimer but rather support a monomeric pseudo-octahedral structure, [Cu(2,2′-bipyridine) 2 (NCS) 2 ], containing magnetically isolated cupric ions exhibiting essentially Curie law behavior.
Who Introduced Typhoid Vaccination: Almroth Wright or Richard Pfeiffer?

The British pathologist Almroth Wright generally is credited with the initiation of typhoid vaccination in 1896. His claims of priority were challenged as early as 1907 in favor of Richard Pfeiffer, a German bacteriologist and a student of Robert Koch. A review of the original literature of the 1890s and the early 1900s revealed that several groups were working on typhoid vaccine at the same time and that the credit for the initiation of typhoid vaccine studies should be shared by these two great researchers.
Separation of phospholipids by high-performance liquid chromatography: all major classes, including ethanolamine and choline plasmalogens, and most minor classes, including lysophosphatidylethanolamine.

Abstract High-performance liquid chromatographic methods for the separation and quantitation of phospholipids were developed and shown to give sensitive, reliable measurements of tissue phospholipids, including difficult-to-resolve pairs such as choline plasmalogen (plasmenyl- choline) and phosphatidylcholine, choline glycerophospholipids and sphingomyelin, phosphatidylinositol and phosphatidylserine, and phosphatidylserine and lysophosphatidylethanolamine. Separations of most phospholipids including those mentioned above are more complete than in existing procedures, and require only 40 min per injection. Utilization of the hexane—2-propanol—water system has an advantage over separation techniques that employ acidic solvents in that the plasmalogens are not hydrolyzed and a less degradative environment for labile lipids is provided. Further, a rapid high-performance liquid chromatographic procedure for the separation of intact ethanolamine plasmalogen (plasmenylethanolamine) from phosphatidylethanolamine was developed. Previous procedures have required derivatized samples or acid hydrolysis of the plasmalogen vinyl ether linkage. A slight modification of the primary method (method I) increases the resolution of lysophos phatidylethanolamine from other classes (method II). A third modification (method III) can replace the standard silicic acid column separation of lipids into neutral, glycolipid, and phospholipid fractions.
MINIMAL DEGREE FOR A PERMUTATION REPRESENTATION OF A CLASSICAL GROUP

The minimal degree for a permutation representation of the finite linear groups, and finite classical groups is determined.
The Potential Threat of Acetyl Fentanyl: Legal Issues, Contaminated Heroin, and Acetyl Fentanyl "Disguised" as Other Opioids

:1-3.]Acetyl fentanyl (N-[1-phenethylpiperidin-4-yl]-N-phenylacetamide)isoneofcountless novelpsychoactive substancesthat have emerged within the American and international drugscene within the last decade. Although some agents such as Salviadivinorum and Mitragyna speciosa are natural botanicals newly“discovered” by entrepreneurs who package and market fortiﬁedversions of the plant product as a “legal high,” the potentiallymost problematic novel psychoactive substances are newlyintroduced synthetic compounds such as acetyl fentanyl.Whether discovered in a laboratory as a part of legitimatescientiﬁc pursuits or created as a part of a manufacturer’s quest totweak an existing compound enough to avoid regulation, thesecompounds often reach users through legitimate retail outlets,Internet Web sites, and street dealers. A variety of syntheticcannabinoids, 3,4-methylenedioxypyrovalerone (MDPV;referred to as “bath salts”), and mephedrone (also referred to asbath salts) were recently problematic before bans; acetyl fentanyluse is still in its infancy, but may eventually follow a similartrajectory.One common feature of novel psychoactive substance use isthe speed at which the drugs emerge as problematic substances.Often “head shop” patrons and Internet-savvy shoppers becomeaware of these compounds before extensive informationappearing in either criminological or medical journals. Thus,experimentation often precedes the development of legal andclinical protocols, forcing law enforcement ofﬁcers andemergency medical professionals to react to situations for whichthey are unprepared. Given the lag between cases presentingthemselves and that information appearing in print in anacademic outlet, several months of increasing use may pass beforethe medical community becomes adequately prepared to dealwith potential overdoses. Initial detection of a novel drug mayhinge on poison center call data—an information source that wasinvaluable when synthetic cannabinoids and bath salts wereemerging—but poison center data may be less useful for noveldrugs such as acetyl fentanyl that are disguised as or mixed withother substances unbeknownst to the actual users or theirphysicians. Other early warning detection systems such asPsychonaut, ReDNet, and Drug Early Warning System also haveutility, but delays inevitably exist in getting information tophysicians who feel overwhelmed and unprepared for dealingwith novel psychoactive drugs. The recent survey by Lank et al
A RANKING OF US GRADUATE PROGRAMS IN URBAN STUDIES AND URBAN AFFAIRS

: A ranking of 33 urban studies and urban affairs programs in the US was developed from peer ratings obtained in a program survey and from citation activity reported in the Social Sciences Citation Index over the 1986–1989 period. A breakdown of citations by broadly defined subject areas is presented. The survey revealed a difference between Ph.D. and MUS/MA programs in the perceived relative importance of peer evaluation and citations as rating criteria. The survey results also indicate that the degree of familiarity with other programs is lower than what has been observed in most social science disciplines.
Enforcement of nineteenth century banking contracts using a marriage rule

Abstract The enforcement of financial and banking contracts is commonly thought to lie within the domain of government law provision. This paper analyzes a case of self-enforcing financial contracts within a banking system in nineteenth century South India. The Chettiars, a merchant-banking caste, relied on religious homogeneity as well as an endogamous marriage rule, whereby members only married others from within the community, to enforce banking contracts within their system. Widely acknowledged to have been an important source of credit locally and throughout South East Asia, this paper describes and analyzes the enforcement mechanisms at work, in the absence of government involvement. Apart from presenting a new case of self-enforced financial contracts, this paper also represents a novel approach to interpreting the social institution of caste, as seen through the rational choice framework.
Interdependent Phosphorylation within the Kinase Domain T-loop Regulates CHK2 Activity

Chk2 is a critical regulator of the cellular DNA damage repair response. Activation of Chk2 in response to IR-induced damage is initiated by phosphorylation of the Chk2 SQ/TQ cluster domain at Ser19, Ser33, Ser35, and Thr68. This precedes autophosphorylation of Thr383/Thr387 in the T-loop region of the kinase domain an event that is a prerequisite for efficient kinase activity. We conducted an in-depth analysis of phosphorylation within the T-loop region (residues 366–406). We report four novel phosphorylation sites at Ser372, Thr378, Thr389, and Tyr390. Substitution mutation Y390F was defective for kinase function. The substitution mutation T378A ablated the IR induction of kinase activity. Interestingly, the substitution mutation T389A demonstrated a 6-fold increase in kinase activity when compared with wild-type Chk2. In addition, phosphorylation at Thr389 was a prerequisite to phosphorylation at Thr387 but not at Thr383. Quantitative mass spectrometry analysis revealed IR-induced phosphorylation and subcellular distribution of Chk2 phosphorylated species. We observed IR-induced increase in phosphorylation at Ser379, Thr389, and Thr383/Thr389. Phosphorylation at Tyr390 was dramatically reduced following IR. Exposure to IR was also associated with changes in the ratio of chromatin/nuclear localization. IR-induced increase in chromatin localization was associated with phosphorylation at Thr372, Thr379, Thr383, Thr389, Thr383/Thr387, and Thr383/Thr389. Chk2 hyper-phosphorylated species at Thr383/Thr387/Thr389 and Thr383/Thr387/Thr389/Tyr390 relocalized from almost exclusively chromatin to predominately nuclear expression, suggesting a role for phosphorylation in regulation of chromatin targeting and egress. The differential impact of T-loop phosphorylation on Chk2 ubiquitylation suggests a co-dependence of these modifications. The results demonstrate that a complex interdependent network of phosphorylation events within the T-loop exchange region regulates dimerization/autophosphorylation, kinase activation, and chromatin targeting/egress of Chk2.
Label-free optical sensing of proteins with porous silicon microcavities

We demonstrate a label free optical biosensor based on macroporous silicon microcavity. The biosensor is tested and characterized by using the streptavidin-biotin couple as a model system.
Long-baseline radio interferometry with independent frequency standards

The present stage of development of long-baseline interferometry using independent atomic frequency standards is reviewed. The technique is being applied to precision geodesy and astrometry and shows great promise as a means for the intercomparison of national time scales at the 1-ns error level. This paper discusses the development of radio interferometry and, in particular, the theory and practice of interferometry over a very wide (effective) bandwidth. The superb phase stability of the hydrogen maser frequency standard in the range of 100 s to several hours makes it the ideal local oscillator for long-baseline Interferometry.
Identification of an androgen receptor in the zonal testis of the salamander (Necturus maculosus)

The testis of the salamander, Necturus maculosus, is advantageous for studying biochemical changes during spermatogenesis because germ cells and associated Sertoli and Leydig cells are topographically separated by stage of development. Using extracts of staged tissue samples and [3H]testosterone (T) in a standard binding assay, followed by Sephadex LH-20 or DNA-cellulose chromatography to separate free and bound steroid, we have identified a T-binding protein having physicochemical characteristics of a classical androgen receptor (AR): high affinity (Kd = 10(-9) M), limited capacity (Bmax) = 10(-10) M or 350 fmol/g tissue) and androgen specificity (T = 5 alpha - dihydrotestosterone greater than progesterone = corticosterone greater than estradiol). AR was present in nuclear extracts, where greater than 80% of binding sites were occupied by endogenous ligand, but was not detectable in cytosol. On linear sucrose gradients, nuclear AR sedimented at 3-4 S in both low and high ionic-strength buffers and, by this and other criteria, was distinguishable from the nonreceptor androgen binding protein (ABP) of the same species. The diffuse distribution of AR in germinal and nongerminal (glandular) tissues at all developmental stages is consistent with a dual localization in Sertoli cells and Leydig cells, as previously reported in mammals, and further suggests a regulatory role of androgen throughout spermatogenesis.
Contrast Echocardiography: Latest Developments and Clinical Utility

Ultrasound enhancing agents (UEAs) are being utilized for a growing number of applications with real-time very low mechanical index (MI) techniques in clinical cardiology today. This article will review recent developments on the safety of UEAs and their effectiveness in myocardial perfusion imaging, three-dimensional quantification of left ventricular function, and vascular imaging. UEAs are now being utilized in all age groups, with new indications that add incremental value to the currently approved by the Food and Drug Administration. These include the incremental value in cardiac imaging, where the off-label analysis of myocardial perfusion observed with UEAs adds to the enhanced endocardial border delineation. In carotid artery imaging, UEAs improve the detection of plaque but also can examine plaque neovascularization. Vascular surgeons now utilize UEAs in the evaluation of endovascular repair to detect endoleaks without the need of ionizing radiation. Newer applications are emerging in the detection of left atrial appendage thrombi and quantification of myocardial blood flow and volume in transplant patients.
Force Dependent Changes in Non-Erythroid Spectrin and Ankyrins

Mechanotransduction in cells describes the process by which external physical stimuli are converted into biochemical activity and plays an important role in many biological functions on both the cell and tissue level. However, the specific mechanisms by which mechanical forces lead to particular molecular and cellular responses are much less understood. We investigate the changes in non-erythroid spectrin and ankyrins as a result of equi-biaxial strain application to cells in culture. Specifically, we focus on the spectrins’ role in the ubiquitination process - a vital process in the regulation of protein degradation- of spectrin and ankyrins. We utilize immune-fluorescence staining in combination with quantitative fluorescence imaging as well as biochemical methods to measure changes in of cell's spectrin and ankyrin content. Protein expression levels and localization between cells exposed to mechanical stimuli of different temporal and spatial profiles are compared.
VLSI architecture: past, present, and future

This paper examines the impact of VLSI technology on the evolution of computer architecture and projects the future of this evolution. We see that over the past 20 years, the increased density of VLSI chips was applied to close the gap between microprocessors and high-end CPUs. Today this gap is fully closed and adding devices to uniprocessors is well beyond the point of diminishing returns. To continue to convert the increasing density of VLSI to computer performance we see little alternative to building multicomputers. We sketch the architecture of a VLSI multicomputer constructed from c. 2009 processor-DRAM chips and outline some of the challenges involved in building such a system. We suggest that the software transition from sequential processors to such fine-grain multicomputers can be eased by using the multicomputer as the memory system of a conventional computer.
Problems in the use of Norton equivalent models for single-phase nonlinear loads

This paper illustrates the problems associated with using Norton equivalent models to represent single-phase nonlinear loads. The study is conducted with a specially-developed harmonics testing station that uses feedback to drive the load voltage to a desired target waveform. We apply various voltage waveshapes with 5% THDv to several types of single-phase nonlinear loads which allow us to compute the Norton parameters. The test results show that the Norton equivalent model for a nonlinear load is not unique and varies significantly with applied voltage waveshape.
Atrial Electrocardiography for Diagnosis of Wide QRS Tachycardia

Excerpt To the editor: The caveats regarding initial therapy for wide QRS complex tachycardia presented by Stewart and coworkers (1) and the companion editorial (2) on diagnosis and therapy in the ...
Interactive Multimedia Courseware and the Hands-on Learning Experience: An Assessment Study

An Experimental Bicycle Dissection Exercise was designed in which students perform an abbreviated and slightly altered version of the “Bicycle Dissection Exercise” offered in the Stanford course, “Mechanical Dissection.” Like the formal course version of the Exercise, student groups were supplied with a bicycle, tools, a manual, and an assigned set of questions; unlike the formal course Exercise, groups in the Experimental Exercise were also supplied with a multimedia stack that explained (through graphics, text, sound and movies) various aspects of the bicycle. This multimedia stack was created to enrich the dissection experience by providing information and background on the mechanics of bicycles. Three groups of students were videotaped performing this Experimental Bicycle Dissection Exercise. The videotapes were then evaluated by a multidisciplinary group of reviewers using a technique called Video Interaction Analysis (VIA). This paper presents a summary of the experimental assessment process and our findings regarding the educational value of the multimedia courseware in exercises with a hands-on component.
Effects of nitroglycerin-induced hypotension on myocardial blood flow in a two vessel occlusion-stenosis anesthetized canine model

The effects of acute occlusion of the left anterior descending coronary artery on regional blood flow (microspheres) to the remote bed supplied by either an unstenosed or a stenosed circumflex coronary artery were assessed during the infusion of intravenous nitroglycerin in 11 open chest barbiturate-anesthetized mongrel dogs. Left anterior descending coronary artery occlusion in the presence of an unstenosed left circumflex artery during nitroglycerin infusion caused systolic aortic and distal circumflex pressure to decrease significantly from 98 ± 4 to 91 ± 3 and from 99 ± 4 to 92 ± 3 mm Hg, respectively. Remote circumflex bed flow was unchanged. The infusion of intravenous nitroglycerin in the presence of a left circumflex stenosis (gradient 31 ± 3 mm Hg) reduced systolic aortic and distal circumflex pressure to 98 ± 2 (p = 0.001) and 71 ± 4 mm Hg (p = 0.001), respectively, and lowered remote circumflex bed endocardial flow from 1.00 ± 0.08 to 0.79 ± 0.07 ml/min per g (p = 0.001). When the left anterior descending coronary artery was occluded under these conditions, systolic aortic and distal left circumflex pressure decreased to 89 ± 3 (p = 0.005) and 62 ± 4 mm Hg (p = 0.08), respectively. Remote circumflex artery bed endocardial and transmural flow were significantly reduced to 0.58 ± 0.07 (p = 0.01) and 0.65 ± 0.07 ml/min per g (p = 0.03), respectively. The decrease in circumflex artery bed endocardial flow after left anterior descending coronary artery occlusion was related directly to the change in distal circumflex artery pressure and inversely to the change in circumflex stenosis resistance (regression analysis). These results suggest that modest hypotension resulting from the infusion of nitroglycerin at the time of acute coronary occlusion may have adverse effects on flow to remote myocardium supplied by a stenosed vessel.
Interactions of Br with Si(111)-7 x 7: Chemisorption, step retreat, and terrace etching.

The dissociative chemisorption of ${\mathrm{Br}}_{2}$ on Si(111)-7\ifmmode\times\else\texttimes\fi{}7 and the effects of spontaneous etching have been studied with scanning tunneling microscopy as a function of temperature, flux, and fluence. At room temperature, the Si surface retains the 7\ifmmode\times\else\texttimes\fi{}7 reconstruction, and bias-dependent imaging reveals Br bonding to adatom and rest-atom dangling-bond sites. For 700\ensuremath{\le}T\ensuremath{\le}900 K, terrace etching involves Si removal from adatom sites and conversion to a 1\ifmmode\times\else\texttimes\fi{}1 periodicity that is stabilized by Br. In this temperature range, bilayer step flow etching dominates and Si removal is fastest along 〈11\ifmmode\bar\else\textasciimacron\fi{}0〉. Regrowth structures derived from six-membered Si rings terminated by Br appear near the bilayer steps. They are more common near steps that descend along [1\ifmmode\bar\else\textasciimacron\fi{} 1\ifmmode\bar\else\textasciimacron\fi{}2] than those that descend along [12\ifmmode\bar\else\textasciimacron\fi{}1] or [2\ifmmode\bar\else\textasciimacron\fi{}11], a distribution that reflects differences in the atomic scale bonding at the steps. Step flow continues at 1000 K but terrace pitting is also activated. This produces triangular bilayer pits bounded by 〈11\ifmmode\bar\else\textasciimacron\fi{}0〉 edges. Analysis yields the ratio of the rates of formation of terrace pits and step kink formation, giving a difference in activation energies for these processes of 0.8 eV. Flux-dependent studies at 1000 K show that pit sizes and densities vary dramatically, an effect related to the mean Br content on the terrace. No such dependence was observed at 900 K because pits could not be formed and the terraces were inactive once converted to 1\ifmmode\times\else\texttimes\fi{}1. At 1100 K, etching produces disordered vacancy clusters in the adatom layer. The presence of small ordered domains amidst randomly distributed adatoms is attributed to facile local removal. In all cases removal proceeds in a layer-by-layer fashion because of the striking anisotropy in etching energetics.
SLAC rf photocathode gun test facility

A high brightness electron injector is a necessary component for x-ray FELs. A dedicated rf gun test facility is being developed at SLAC to measure the phase space distribution from a photocathode rf gun generated electron beam. This Gun Test Facility will allow optimization of the beam brightness by independently adjusting parameters such as accelerating field, laser pulse shape and total charge. The test facility is comprised of a single S-band klystron, 3 m SLAC linac section, analyzing magnet, diagnostic section, a cathode drive laser and the gun under test. The laser is comprised of a Nd:YLF oscillator and a Nd:glass regenerative amplifier. The light incident on the cathode is capable of both normal and near grazing incidence and is currently frequency quadrupled into the UV. In the near future a Nd:glass oscillator will be installed which will be capable of generating pulses as short as 200 fs. This oscillator will be used to make emittance measurements as a function of the laser pulse width and shape. Both oscillators will be phase-locked to the 24th sub-harmonic of the linac frequency. Emittance measurements will be made downstream of the linac at an electron beam energy of approximately 30 - 50 MeV using a quad scan with a beam profile screen and/or a wire scanner to measure the spot size. A current transformer and a Faraday cup will be used to measure the charge while a streak camera or a transition radiator can be used to measure the micropulse width. The first gun to undergo testing will be the BNL/SLAC/UCLA 1.6 cell symmetrized cavity gun with a copper cathode. With field gradients in the gun as high as 150 MV/m, using solenoidal emittance compensation and spatial and temporal flat top laser pulses, PARMELA simulations predict normalized emittances of less than 1.5 pi mm-mrad with 10 ps long pulses and 1 nC of charge after acceleration in a 3 meter linac section to about 30 MeV. Appropriate additional acceleration can further reduce the emittance below 1 pi mm-mrad.
There's no two‐way symmetric about it: A postmodern examination of public relations textbooks

This article critiques five of the influential textbooks in post‐secondary public relations using a postmodern and deconstructive approach. It argues that public relations textbooks uncritically present a singular view of PR as an ever‐evolving and positive social force. The essay examines versions of public relations history presented in textbooks and points out how alternative and less positive versions of that history are not expressed. Public relations definitions, theories, and practices in the textbooks are deconstructed including the two‐way symmetric conceptualization of PR, notions of a socially‐responsible PR and the role of the free marketplace of ideas. It calls for pedagogies that encourage students to become skeptical rather than credulous readers and raise their awareness of alternative ways of understanding public relations and corporate communication.
Modification and further evaluation of a fluorescein-labeled peanut agglutinin test for identification of Haemonchus contortus eggs.

Abstract Gastrointestinal nematodes of the family Trichostrongylidae are the most important parasites of sheep, goats and other ruminants worldwide. Of this group, Haemonchus contortus is usually the most damaging species, particularly in warmer climates or during the summer. It is therefore useful to be able to rapidly differentiate infections with this nematode from other, less pathogenic, species. However, aside from Nematodirus spp., there are only subtle differences between the egg morphology within the trichostrongyles, making it very difficult to identify eggs to the species level. It has been shown previously that peanut agglutinin specifically binds to Haemonchus eggs and not those of other trichostrongyle species. By using this lectin conjugated to fluorescein isothiocyanate, binding to Haemonchus eggs can be visualized under ultraviolet illumination. We adapted this test using eggs purified by routine sugar centrifugation methods and evaluated 26 diagnostic samples from ruminants submitted to our laboratories in Oregon and Georgia. Very good correlations were seen between this test and larval culture (adjusted R2 = 0.72132; F1,25 = 65.7; p
Tooth scaling and evolutionary dwarfism: An investigation of allometry in human pygmies

Gould has predicted that in rapidly dwarfed lineages the postcanine teeth exhibit a different scaling pattern than is the normal interspecific trend. His prediction of strong negative allometry has not been frequently tested in quantitative detail. Here we present results of scaling analyses of the molar teeth in African pygmies compared with other Africans of larger size and in Philippine pygmies compared with Filipinos of larger size. We find a pattern of strong negative allometry of tooth size to skull and body size in both these comparisons. This scaling pattern is explained by recourse to the developmental bases (known or inferred) of dwarfing in these populations. Body size decrease is related to low levels of the growth control substance insulin-like growth factor I (IGF-I), which does not appear to affect the size of the dentition. The implications of such developmental information for our understanding of allometric patterns in general, and dwarfing events in particular, are discussed.
Toward a middle-range theory of individual-level strategic leadership transitions

Abstract Initial actions in a new official's administration set the stage for later successes or failures. This paper draws on the experiences of the three state agency directors to offer suggestions to guide public managers. While written to provide guidance for a newly appointed state agency head, this paper suggests a similarly deliberate approach to “taking charge” for all public managers entering new positions. The paper concludes by outlining the deliberate processes suggested by the agency directors involved in creating conditions leading to a change or transformation of the organization. The paper also offers implications for newly appointed agency directors and the appointing authority.
Nicotinic cholinergic receptor binding sites in the brain: regulation in vivo

Tritiated acetylcholine was used to measure binding sites with characteristics of nicotinic cholinergic receptors in rat brain. Regulation of the binding sites in vivo was examined by administering two drugs that stimulate nicotinic receptors directly or indirectly. After 10 days of exposure to the cholinesterase inhibitor diisopropyl fluorophosphate, binding of tritiated acetylcholine in the cerebral cortex was decreased. However, after repeated administration of nicotine for 10 days, binding of tritiated acetylcholine in the cortex was increased. Saturation analysis of tritiated acetylcholine binding in the cortices of rats treated with diisopropyl fluorophosphate or nicotine indicated that the number of binding sites decreased and increased, respectively, while the affinity of the sites was unaltered.
PTEN gene therapy induces growth inhibition and increases efficacy of chemotherapy in prostate cancer.

Abstract The PTEN gene, located on chromosome 10, is a phosphatase in the phosphatidylinositol 3′-kinase (PI3'K)-mediated signal transduction pathway. PTEN inhibits the activation of Akt, a serine-threonine kinase involved in proliferative metabolic and anti-apoptotic pathways, and has tumor suppressor properties. We used a PTEN adenoviral vector, Ad-MMAC, to assess the role of PTEN in the treatment of prostate cancer. Infection of Ad-MMAC in PC-3 and LNCaP prostate cancer cells (PTEN deleted, up-regulation of phosphorylated Akt) resulted in PTEN expression and significantly decreased growth compared with Ad-CTR or mock infected cells. Infection of Ad-MMAC did not inhibit the growth of DU-145 cells (wild-type PTEN). Combination therapy with Ad-MMAC and doxorubicin improved the efficacy of PTEN gene therapy in PC-3 and DU-145 cells. These data demonstrate that PTEN gene therapy can effectively treat some prostate cancers that have genomic alterations in PTEN. In others, PTEN gene therapy combined with chemotherapy is more effective.
Left atrial appendage as a target for reducing strokes: Justifiable rationale? Safe and effective approaches?

u t b One of every six strokes occurs in patients with atrial fibrillation (AF). Among the patients in whom a left atrial thrombus is found, 90% are located in the left atrial appendage (LAA). Given the morbidity and disability associated ith stroke, various targets to decrease this dreaded comlication have been identified. AF itself appeared intuitively to be a viable target; however, ntiarrhythmic drugs, even when effective in reducing AF, ave not been shown to reduce stroke risk. To date, anticoaglation remains the mainstay for managing stroke risk with AF. arfarin decreases the likelihood of stroke by 60% to 70% ompared with no antithrombotic therapy and 30% to 40% ompared with aspirin. Significant limitations with warfarin se, including hemorrhagic stroke, prevalence of subtherapeutic anticoagulation, narrow therapeutic window, need for close monitoring, and various diet and drug interactions, greatly limit the actual utility of this proven therapy. The severity of the disease (stroke) combined with the lack of safe and effective therapies has understandably led to the development of novel therapies, including a variety of surgical and percutaneous approaches that target the LAA. In this issue of Heart Rhythm, Bartus et al report the first human experince of a percutaneous epicardial LAA ligation technique sing the LARIAT snare device (SentreHEART Inc., Palo lto, CA, USA). This technique involves a combined endoardial and percutaneous subxiphoid epicardial magnet-tipped ire-guided approach and snaring of the LAA at the ostium. hree screening computerized tomography (CT) scans were erformed to assess the appropriateness of the appendage anatmy and transesophageal echocardiography (TEE) with conrast fluoroscopy used to assess effective closure. Ten of 11 atients (9 with percutaneous epicardial access and 2 with imultaneous open surgical mitral valve replacement) had sucessful acute ligation. Follow-up was available at 60 days in 6 f these patients, and 4 of these had persistent closure. In order
Tu1456 Predictors and Significance of Endoclip Retention After Endoscopic Mucosal Resection (EMR) of Large (>20 mm) Colon Polyp

Predictors and Significance of Endoclip Retention After Endoscopic Mucosal Resection (EMR) of Large (>20 mm) Colon Polyp Wei-Chung Chen*, Nirav Thosani, Sachin Batra, Gottumukkala S. Raju Gastroenterology, Hepatology and Nutrition, The University of Texas Medical School at Houston, Houston, TX; The Methodist Hospital, Houston, TX; The UT MD Anderson Cancer Center, Houston, TX Background and Aim: Endoclips are commonly used to prevent bleeding and close the defect after endoscopic mucosal resection (EMR). There is growing concern that clip closure may result in tumor in-growth (“buried glands) and prolonged clip retention may interfere with treatment of residual polyps. Our goal is to report prolonged endoclip after EMR, to identify factors predictive of clip retention, and to assess whether clip retention results in tumor ingrowth and recurrence. Method: We performed a retrospective review of prospectively maintained database of all colonic EMR performed by GSR at the UT MD Anderson Cancer Center (6/2009 6/2102). Database contained information regarding patient demographic, referral pattern, polyp characteristics, EMR technique, complications, pathology report and follow up colonoscopy details. All continuous variables were described as medians and IQR and compared using Wilcoxon rank sum test. All categorical variables were listed as frequency and percentages and compared using fisher’s exact test. Results: Of 73 consecutive patients (93 polyps) with polyp size greater than 20 mm, 7 patients (14 polyps) were referred for surgical resection without EMR. Endoscopic Mucosal Resection, was undertaken in 78 polyps in 66 patients (33 men and 33 women). Majority of EMRs were undertaken in the right colon (n 56; 72%) for flat lesions (Paris classification 0-IIa: n 65; 84%) Patient demographic, polyp characteristics and EMR details are shown in (Table 1). Clip Closure of EMR Defect was undertaken in 74 of 78 EMRs. The median number of clips per EMR was 6 (IQR of 4 to 8). Delayed bleeding was noted in 3 cases (3.85%) after resection, which required hospitalization and transfusions; and one patient required endoscopic clip application. Colonoscopy Follow up was performed in 66 EMR cases between 3 to 6 months. Clip Retention was observed in 6 of 63 EMR cases (total 9 retained clips; 1 clip in 3 cases and 2 clips in 3 cases) at follow up colonoscopy. The total clip retention rate was 9.52%. Among patients with retained clips, none of them had recurrence of neoplasia based on histopathology from biopsies obtained at scar site. Predictors of Clip Retention: None of the patient demographic, polyp characteristics and EMR details predicted clip retention. (Table 2). Conclusion: Overall endoclip retention rate at 6 months is low (9.52%) and is not associated with recurrence of neoplasia. None of the clinical and endoscopic factors predict clip retention.