cssi/SciSciGPT-SciSciNet huggingface dataset:
Tuning approximate dynamic programming policies for ambulance redeployment via direct search

In this paper we consider approximate dynamic programming methods for ambulance redeployment. We first demonstrate through simple examples how typical value function fitting techniques, such as approximate policy iteration and linear programming, may not be able to locate a high-quality policy even when the value function approximation architecture is rich enough to provide the optimal policy. To make up for this potential shortcoming, we show how to use direct search methods to tune the parameters in a value function approximation architecture so as to obtain high-quality policies. Direct search is computationally intensive. We therefore use a post-decision state dynamic programming formulation of ambulance redeployment that, together with direct search, requires far less computation with no noticeable performance loss. We provide further theoretical support for the post-decision state formulation of the ambulance-deployment problem by showing that this formulation can be obtained through a limiting argu...
Supply chain analysis of e-tailing versus retailing operation – a case study

The swift growth of e-commerce or e-tailing as a consumer retail channel has made it a serious competitor to traditional retail channels and is changing consumers’ purchasing behaviour. The purpose of this case study, based on Target and Amazon.com, is to analyse the attributes of traditional retailing, e-tailing, and hybrid supply chain models to form conclusions about the feasibility of an idealised supply chain model for the future. An integrated and generalised modelling framework is used that incorporates Six Sigma – define, measure, analyse, improve, control methodology leveraging various tools, including process flow maps, cause and effect diagram, performance efficiency metrics, failure mode and effects analysis FMEA, and Monte Carlo simulation. Based on this analysis and research, the conclusion is that the idealised supply chain of the future may evolve into a hybrid supply chain, which includes both e-tail and retail channels. The main recommendations from this study include assessing the risks of migrating to such a hybrid supply chain and to leverage the recommended actions provided in the hybrid FMEA. To facilitate more effective and mature processes, this study can guide researchers in exhaustive empirical evaluations of hybrid supply chains, gather experiences and lessons learned for practitioners.
Adolph Barkan (1845-1935), European ophthalmologist in San Francisco.

Adolph Barkan, a mid-19th century Central European–born and –trained ophthalmologist, spent almost half his nearly 91 years in a very successful career on the West Coast of the United States. His activities included intimate involvement in the development of a private medical school and with this school’s acquisition by Stanford University as its medical school. In retirement, he founded, financed, and stocked a large medical history library at that university. In the 1890s, Siegfried Czapski, the developer of the Carl Zeiss corneal biomicroscope, the direct precursor of today’s slitlamp, incorporated Barkan’s suggestion that Czapski replace the planned monoscopic binocular microscope with a stereoscopic binocular one, an essential modification of the device. This Zeiss invention lacked only the slit illumination of today’s instrument. Comments he wrote in a memoir-diary during World War I explain how he came to the decision to stray and to stay so far from his roots.
Photosensitivity: a current biological overview.

Context: The level of interest in photoirritation (phototoxicity) has increased because of the awareness among the scientific community of the increase in the UV portion of the solar spectrum reaching the earth. The need of new chemicals and drugs puts pressure on pre-test methods for side effects, especially interactive adverse effects with UV light. So pre-marketing clinical trials conducted before a new drug is licensed are essential, as such, at the early phases of the discovery process of the drug/chemical, developing an efficacious photosensitivity testing system is prudent to avoid such potential side effects.Objectives: To review published literature and provide an overview on exogenous photosensitivity and assays used to evaluate the photosensitivity potential of drugs/chemicals. As well as testing considerations by the Regulatory bodies (namely, the Organization for Economic Cooperation and Development, the U.S Food and Drug Administration and the European Union regulatory agencies).Materials an...
Drop properties after secondary breakup

Drop properties during and after secondary breakup in the bag, multimode and shear breakup regimes were observed for shock-wave-initiated disturbances in air at normal temperature and pressure. Test liquids included water, n-heptane, ethyl alcohol and glycerol mixtures to yield Weber numbers of 15--600, Ohnesorge numbers of 0.0025-0.039, liquid/gas density ratios of 579-985 and Reynolds numbers of 1060-15080. Measurements included pulsed shadowgraphy and double-pulsed holography to find drop sizes and velocities after breakup. Drop size distributions after breakup satisfied Simmons' universal root normal distribution in all three breakup regimes, after removing the core (or drop-forming) drop from the drop population for shear breakup. The size and velocity of the core drop after shear breakup was correlated separately based on the observation that the end of drop stripping corresponded to a constant Ertvrs number. The relative velocities of the drop liquid were significantly reduced during secondary breakup, due both to the large drag coet~cients caused by drop deformation and the reduced relaxation times of smaller drops. These effects were correlated successfully based on a simplified phenomenological theory.
The method of constant stimuli is inefficient

Simpson (1988) has argued that the method of constant stimuli is as efficient as adaptive methods of threshold estimation, and has supported this claim with simulations. We show that Simpson's simulations are not a reasonable model of the experimental process, and that more plausible simulations confirm that adaptive methods are much more efficient than the method of constant stimuli.
Chromium carcinogenicity: California strategies

Abstract Hexavalent chromium was identified by California as a toxic air contaminant (TAC) in January 1986. The California Department of Health Services (CDHS) concurred with the findings of the International Agency for Research on Cancer that there is sufficient evidence to demonstrate the carcinogenicity of chromium in both animals and humans. CDHS did not find any compelling evidence demonstrating the existence of a threshold with respect to chromium carcinogenesis. Experimental data was judged inadequate to assess potential human reproductive risks from ambient exposures. Other health effects were not expected to occur at ambient levels. The theoretically increased lifetime carcinogenic risk from a continuous lifetime exposure to hexavalent chromium fell within the range 12–146 cancer cases per nanogram hexavalent chromium per cubic meter of air per million people exposed, depending on the potency estimate used. The primary sources found to contribute significantly to the risk of exposure were chrome platers, chromic acid anodizing facilities and cooling towers utilizing hexavalent chromium as a corrosion inhibitor. Evaluation of genotoxicity data, animal studies and epidemiological studies indicates that further consideration should be given to the potential carcinogenicity of hexavalent chromium via the oral route.
Effect of trans fatty acids on protein utilization and serum cholesterol.

Rats were fed PER diets containing various proportions of cis and trans fatty acids as triolein, trielaidin, soybean oil (SO) or hydrogenated SO at 7.8% by weight of the diet. Additional rats were fed SO or hydrogenated SO at 20.1% of the diet. The PER, although in the normal range for casein, was significantly (P < 0.01) lower in rats fed trielaidin. Food consumption and weight gains were slightly greater in trans-fed than cis-fed rats. The former had greater fecal fat excretion than the latter; serum cholesterol levels of the former were lower with the 7.8% but not the 20.1% fat diet.
Potentiometric enzyme-amplified flow injection analysis detection system: behavior of free and liposome-released peroxidase

Abstract A flow injection analysis (FIA) system was designed for the determination of free and liposome-released peroxidase activity. the inclusion of an extra washing channel in the FIA system provided a solution to problems of electrode fouling and slow recovery of response. the addition of Triton X-100 to acetate buffer resulted in an effective and reliable wash solution, and improved the electrode recovery rate by a factor of three. the sensitivity also increases by about 20% for the enzyme with 3 mU activity by using the wash solution containing Triton X-100.
Multisite Case Study of Florida's Millennium High School Reform Model

This study should have immediate utility for the United States and beyond its borders. School-to-work approaches to comprehensive reform are increasingly expected of schools while legislative funding for this purpose gets pulled back. This multisite case study launches the first analysis of the New Millennium High School (NMHS) model in Florida. This improvement program relies upon exemplary leadership for preparing students for postsecondary education
Wiggler and undulator magnets — an overview

Abstract Wiggler and undulator magnets as radiation sources in electron storage rings are reviewed. The review covers (a) the spectral properties of wiggler/undulator radiation, (b) the technology available for their construction, (c) the interaction of these devices with the stored electron beam, (d) experience with existing devices, (e) plans for future devices at laboratories around the world and (f) beam line design considerations.
Use of intravenous gamma globulins in neuroimmunologic diseases

Intravenous gamma globulin (IVIg) is used in the treatment of immunologic diseases that affect the entire neuroaxis, including the brain, spinal cord, peripheral nerves, muscles, and neuromuscular junction. The panel reviewed the available literature on the use of IVIg in order to evaluate the efficacy of this therapy in neuroimmunologic diseases. In prospective, rigorously controlled, double-blinded clinical trials, IVIg was found to have proven efficacy in the Guillain-Barre syndrome, chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, dermatomyositis, and Lambert-Eaton myasthenic syndrome. It was found to be probably effective in myasthenia gravis and polymyositis, and possibly effective in several other neuroimmunologic diseases. Further studies are needed to evaluate the use of IVIg for neuroimmunologic diseases in which its efficacy is suspected but not proven and to elucidate its mechanisms of action.
Control of Membrane Asymmetry by P4-ATPases

The plasma membrane of eukaryotic cells is an asymmetric structure with the cytosolic leaflet highly enriched in phosphatidylserine (PS) and phosphatidylethanolamine (PE), whereas these lipids are rare in the extracellular leaflet. This asymmetric organization is generated by phospholipid flippases in the type IV P-type ATPase (P4-ATPases) family that pump specific phospholipids (e.g. PS and PE) unidirectionally to the cytosolic leaflet. Cells typically express several P4-ATPases that localize to the Golgi, plasma membrane and endosomal system, and differ in substrate specificity. We discovered a crucial role for P4-ATPases in budding protein transport vesicles from the trans-Golgi network (TGN) and early endosomal membranes. Current studies are aimed at understanding how P4-ATPases from Saccharomyces cerevisiae recognize and flip specific phospholipid species to generate membrane asymmetry, and why this plays an important role in budding certain types of transport vesicles. We have succeeded in mapping a number of residues that determine the phospholipid substrate specificity of the P4-ATPases Drs2 and Dnf1 to the first four transmembrane segments. These studies imply that the P4-ATPases use a non-canonical mechanism to recognize and transport substrate relative to closely related Ca++-ATPase. In addition, we can mutationally “tune” the substrate specificity of Drs2 and Dnf1 and use these mutants to probe the cellular requirements for specific P4-ATPase substrates. Neo1 is an essential P4-ATPase in yeast that is closely related to ATP9A and 9B in mammalian cells. Recent studies imply that Neo1 is the primary PE flippase in yeast and a mutation in Drs2 that enhances its recognition of PE can functionally replace Neo1 in vivo.
Plastid gene expression during fruit ripening in tomato

A tomato chloroplast genome map has been constructed with the restriction enzymes Hpa I, Pvu II, and Sal I. Twelve plastid genes have been located on the tomato plastid genome (159 kb).
RESEARCH ON ICING FLASHOVER CHARACTERISTIC OF DIFFERENT SHED TYPE COMPOSITE INSULATORS

With the global climate change, icing has become a common problem to China power system. Flashover problems caused by icing insulators have a serious threat to the safe operation of transmission and substations. It may result in tripping accidents, causing huge economic losses. In this paper, the artificial simulation icing flashover tests of ultra high voltage composite insulator with different shed structures (ordinary shed and anti-icing shed) have carried out in the environmental climate chamber of National Engineering Laboratory. A certain power frequency voltage applied on insulator string sample between the whole icing process, the environment temperature in the test chamber is -10 °C, the conductivity of water which used to icing is 100 μ S / cm, the temperature of water is 4 °C, the thickness of ice coating is about 13-15mm. The test result shows that the flashover voltage values are not same with different insulator shed. When equivalent salt deposit density p ESDD is 0.08mg/cm 2 , the flashover voltage gradient of composite insulator with ordinary shed is 54.4kV/m, but the flashover voltage gradient of anti-icing type insulator is 61.0-69.4kV/m, which increased about 12%-27% than the ordinary shed type, and the increasing amplitude of flashover voltage is proportional to the number of anti-icing shed. According to test phenomenon, we can find obviously that anti-icing shed of insulator is very useful to prevent ice bridged. Based on the analysis of the test results, this paper give the reasonable external configuration of ultra high voltage transmission lines to prevent icing flashover which is very important to improve the reliability of UHV transmission project in ice covered condition.
Profile and depth of microcraters formed in glass

Abstract By sectioning glass targets impacted by a large number of hypervelocity particles it has been possible to observe the profile of microcraters and to get a direct measurement of their depth. The crater depth to projectile diameter ratio, P/d is 1.30 for a 15 × 10 −12 g iron projectile hitting the target at 6 km/s. The energy-dispersive X-ray attachment to the scanning electron microscope (SEM) shows that most of the projectile remains in the crater, up to 6 km/s impact velocities.
Pricing Efficiency in the Live Cattle Futures Market: Further Interpretation and Measurement

The pricing efficiency of the live cattle futures market is evaluated using out-of-sample forecasts from an econometric model, an ARIMA model, and composite forecasting procedures. In terms of the mean-squared error criterion, a necessary condition for market efficiency, at least one of the models, and frequently more, forecasted more accurately than did the futures market. However, market simulation results based on the most accurate forecasts generated large risk-return ratios. These results do not show strong evidence of inefficiency and call into question the use of only mean-squared errors to examine a market's pricing efficiency.
A physiologic study of motility changes following selective gastric vagotomy

Summary Physiologic studies were done in dogs with stimulation of the thoracic vagus and recording of motility changes in the abdominal viscera, namely the stomach, first part of the duodenum, third part of the duodenum, jejunum, ileum, colon and gallbladder. We have shown by this technique that: o 1. Following selective gastric vagotomy, the motility response in the stomach is totally absent while the remaining viscera are reactive. 2. The influence of the gastric branches from either right or left trunk extends through the second part of the duodenum. 3. The hepatic branch of the left vagus innervates the gallbladder and proximal duodenum but has no influence on the stomach. 4. The celiac branch influences the entire gastrointestinal tract from the proximal duodenum through the ascending colon. 5. Selective gastric vagotomy may prove to be a logical refinement of total abdominal vagotomy.
AN IMMUNE SERUM AGAINST THE NORTH AMERICAN CORAL SNAKE (MICRURUS FULVIUS FULVIUS) VENOM OBTAINED BY PHOTOOXIDATIVE DETOXIFICATION.

Abstract : Photooxidation of crude Micrurus fulvius fulvius venom by visible light in the presence of methylene blue resulted in the detoxification of this venom. Rabbits inoculated with the photooxidized venom produced an immunoglobulin which protected mice against many-fold lethal doses of the unaltered venom. Neither local nor systemic ill effects were observed in rabbits or mice. The effectual and harmless toxoid obtained could be used for active immunization, in suitable circumstances, as well as for production of antisera for passive immunization. (Author)
Pathways to equity in mathematics education: how life experiences impact researcher positionality

This study examined the life histories of a group of emerging scholars in the field of mathematics education who identify themselves as having a particular interest in and concern for issues of equity and diversity. Experiences of being the "other," "bearing witness" to "othering experiences," and "orienting experiences" in relation to issues of equity proved to be prominent themes in participants' life histories. These experiences were then linked to the positionality that these scholars now have in relation to their research in mathematics education.
Cruise Passengers' Decision-Making Processes

Abstract While various models for understanding tourists' decision-making processes have been conceptualized (e.g., Crompton, 1992; Gursoy & McCleary, 2004; Huan & Beaman, 2003), few studies have attempted to examine them. The current study, guided by Crompton's choice set conceptualization, utilized qualitative methods (focus groups) to investigate the role of choice sets while examining the underlying reasons and social influences for passengers' cruise vacation choice. Findings of the study suggest the existence of two groups of cruisers: those who go through complex decision making and those who are brand loyal. Further theoretical and managerial implications were discussed.
Gerbode defect: Another nail for the 3D transesophagel echo hammer?

Acquired type of LV to RA shunt (Gerbode defect) is rare form of intracardiac shunt which is due to complications of invasive cardiac procedures, endocarditis, trauma or myocardial infarction. Increasing invasive and recurrent cardiovascular procedures have led to more acquired cases of what used to be a predominant congenital heart defect. Advanced cardiac imaging techniques and awareness of this rare pathology may account for the increased number of case reports in the last two decades Advanced cardiac imaging tools such as cardiac CT, MRI and Real-time 3D echocardiography provide definitive diagnosis and anatomic characterization of the shunt. Real-time 3D echocardiography is an imaging technique with arguably the most advantages. It is not only a diagnostic tool; it has also become an integral part of percutaneous and surgical treatment. Although surgical repair is the usual treatment for this shunt, percutaneous catheter-based closure has seen significant success as a less invasive treatment in selected patients in the last decade. In summary, a beneficial side effect of the increasing frequency of acquired Gerbode defect has been the corresponding development of newer diagnostic tools and less invasive treatments. This article presents etiologic, diagnostic and treatment changes of acquired LV–RA shunts over the last two decades.
Specific heat measurements by non-contact calorimetry

Abstract The specific heat and the related thermodynamic functions of highly undercooled liquids are essential in analyzing the nucleation kinetics during crystallization and glass formation from the liquid or solid state. However, for metals and alloys the measured data are very scarce and in general limited to low-melting point systems. For alloys which exhibit higher melting points, such data generally do not exist. Thus, in order to measure specific heat of metals and alloys at elevated temperatures a new modulation method is being developed. The basic principle for this measurement and preliminary data on solid samples are discussed.
Growth and development of bald-cypress/water-tupelo stands under continuous versus seasonal flooding☆

Abstract The influence of flooding on mixed stands of bald cypress (Taxodium distichum (L.) Rich.) and water tupelo (Nyssa aquatica L.) was studied in two second-growth stands, one continuously flooded (CF) with flowing water and the other seasonally flooded (SF). Both stands had about 50 m2 ha−1 of basal area, of which 84% was bald cypress and 16% water tupelo. In the SF stand, large bald cypress grew fast, and water tupelo had high mortality rates. Bald-cypress growth was slower in the CF stand than the SF stand, but water-tupelo growth rate was slightly faster. As a result, water tupelo was more competitive against bald cypress in the CF stand, and did not lose basal area as it did in the SF stand. Basal-area changes indicate the composition of the SF stand will approach pure bald cypress, while the bald-cypress/water-tupelo mixture will be maintained in the CF stand.
Inputs of phosphorus from precipitation to Lake Michigan

Precipitation samples were collected at six locations around Lake Michigan and analyzed for the concentrations of the different forms of phosphorus present. The concentrations were found to be higher in the southern part of the lake. Precipitation-weighted concentrations of total phosphorus and dissolved reactive phosphates were found to be 0.023 mg/1 and 0.011 mg/1, both higher than the concentrations found in the open lake of 0.009 and 0.002 mg/1. Inputs of total phosphorus to the lake were calculated to be 1.0 × 106& kg/yr or about 18% of the present phosphorus budget of the lake. More than 40% of the phosphorus in precipitation is in the form of dissolved reactive phosphates and it is estimated that about 0.6 × 106& kg/yr of the phosphorus coming into the lake in precipitation becomes available to organisms in the lake.
The relation between employee organizational and professional development activities

Abstract A model is presented showing hypothesized common and parallel antecedents of employee organizational development activity (ODA) versus professional development activity (PDA). A common antecedent is expected to affect both ODA and PDA, while a parallel antecedent is expected to affect its corresponding work referent. This model was tested using a sample of 197 medical technologists over a four year time period. Prior ODA and PDA were controlled for before testing hypotheses. Results showed that the common antecedent of learning motivation was a robust indicator of both ODA and PDA. Looking at parallel antecedents, job satisfaction and affective organizational commitment had a positive impact on ODA, while occupational satisfaction and affective occupational commitment had a positive impact on PDA. ODA had a negative impact on subsequent intent to leave organization, but PDA did not have a similar impact on intent to leave profession. Study limitations, issues around operationalizing ODA and PDA, and future research directions are discussed.
CD20 is a molecular target for scFvFc:zeta receptor redirected T cells: Implications for cellular immunotherapy of CD20+ malignancy

Abstract The CD20 molecule was evaluated as a B-cell lymphoma target epitope for T cells expressing a CD20-specific single-chain FvFc-zeta (scFvFc:zeta) chimeric receptor. A cDNA construct consisting of a murine kappa leader sequence, CD20-specific scFv, human immunoglobulin (Ig) G1 hinge-C(H)2-C(H)3, the human CD4 transmembrane, and the intracellular signaling domain of the human CD3 complex's zeta chain was synthesized by polymerase chain reaction splice-overlap extension. The human CD4+ Jurkat cell line was electroporated with the CD20-specific scFvFc:zeta construct cloned into the mammalian expression vector pcDNAneo. Western blot analysis of transfectant whole cell lysate with an anti-zeta antibody demonstrated the expression of both endogenous zeta and the chimeric receptor protein, with a mobility consistent with the expected molecular weight of 66 kD under reducing conditions; nonreduced lysate revealed a chimeric receptor complex of approximately 132 kD. The scFvFc:zeta receptor was present on the cell surface as detected by flow cytometry of T-cell transfectants stained with an anti-mouse Fab-specific antibody and anti-human Fc gamma-specific monoclonal antibody. Coculture of Jurkat transfectants with CD20+ lymphoma cells resulted in the accumulation of interleukin (IL)-2 in culture supernatants as detected by ELISA. IL-2 production was triggered by the specific interaction between the CD20 molecule and the scFvFc:zeta as IL-2 was not detected in cultures with mock transfected Jurkat cells or CD20- stimulator cells. Furthermore, IL-2 production was inhibited by the addition of a soluble anti-CD20 monoclonal antibody to cocultured Jurkat transfectants and CD20+ stimulator cells. The capacity of CD20 to trigger the lytic machinery of scFvFc:zeta-expressing cytotoxic T lymphocytes (CTLs) was assessed using the murine allo-specific CD8+ CTL clone 2c. CD20-specific redirected cytolytic activity against human lymphoma targets was observed with 2c transfectants in a 4-hour chromium release assay. These results demonstrate that CD20 can serve as a target epitope for scFvFc:zeta receptor-expressing T cells. Biol Blood Marrow Transplant 1998;4(2):75-83.
Some problems caused by birefringence in dielectric mirrors

Some problems caused by birefringence in dielectric mirrors are discussed with emphasis on the effects in laser cavities. Polarization sensitive applications are considered.
Anatomy of banking crises in developing and emerging market countries

Abstract This paper uses a Binary Classification Tree (BCT) model to analyze banking crises in 50 emerging market and developing countries during 1990–2005. The BCT model identifies three conditions (and the specific threshold of the key indictors) at which the vulnerability to banking crisis increases—(i) very high inflation, (ii) highly dollarized bank deposits combined with nominal depreciation or low bank liquidity, and (iii) low bank profitability—which highlight that foreign currency risk, poor financial soundness, and macroeconomic instability are important drivers of banking crises. The results also emphasize the importance of conditional thresholds in triggering crises, in that banking crises are underlined by a combination of vulnerabilities—or a sequence of (non-linear) conditions—rather than the deterioration of a unique factor.
Effect of Age on Cerebral Blood Flow Velocity and Incidence of Vasospasm After Aneurysmal Subarachnoid Hemorrhage

Background and Purpose— Current transcranial Doppler criteria for vasospasm after aneurysmal subarachnoid hemorrhage are not age specific. We analyzed the effect of age on cerebral blood flow velocity changes after subarachnoid hemorrhage and constructed an age-adjusted predictive model of cerebral blood flow velocity in subarachnoid hemorrhage patients. Methods— We identified patients with aneurysmal subarachnoid hemorrhage admitted between 1991 and 1999 with a prospective transcranial Doppler database. Eighty-one patients, with complete medical records and transcranial Doppler examinations of the vessels of interest, were included. Patients were subdivided into 2 groups by age: younger, <68 years of age (n=47) and older, ≥68 years of age (n=34). Maximum mean flow velocity and incidence of symptomatic vasospasm were reported. Linear and nonlinear regression analyses were performed. Results— Middle cerebral artery and internal carotid artery mean flow velocity were lower in older patients (median 76 versu...
Calorimetric studies of ligand binding in R67 dihydrofolate reductase.

R67 dihydrofolate reductase (DHFR) is a novel bacterial protein that possesses 222 symmetry and a single active site pore. Although the 222 symmetry implies that four symmetry-related binding sites must exist for each substrate as well as for each cofactor, various studies indicate only two molecules bind. Three possible combinations include two dihydrofolate molecules, two NADPH molecules, or one substrate plus one cofactor. The latter is the productive ternary complex. To explore the role of various ligand substituents during binding, numerous analogues, inhibitors, and fragments of NADPH and/or folate were used in both isothermal titration calorimetry (ITC) and Ki studies. Not surprisingly, as the length of the molecule is shortened, affinity is lost, indicating that ligand connectivity is important in binding. The observed enthalpy change in ITC measurements arises from all components involved in the binding process, including proton uptake. As a buffer dependence for binding of folate was observed, t...
Echocardiographic demonstration of decreased left ventricular dimensions and vigorous myocardial contraction during syncope induced by head-up tilt

Two-dimensional echocardiography was performed during a head-up tilt test in 11 control subjects (group I) and 18 patients with recurrent unexplained syncope. In four patients (group II), the head-up tilt test was negative at baseline and after isoproterenol infusion. Syncope was induced during baseline head-up tilt in nine patients (group III) and after isoproterenol challenge in five (group IV). The echocardiographic variables assessed were left ventricular end-systolic and end-diastolic areas and percent fractional shortening. At the end of head-up tilt, end-systolic area decreased by 4.5 ± 1.3 and 3.0 ± 1.2 cm2in groups III and IV, respectively, compared with 0.5 ± 0.7 and 0.2 ± 0.1 cm2in groups I and II, respectively (p < 0.04). Similarly, end-diastolic area decreased by 5.5 ± 2.6 cm2in group III compared with 2.7 ± 1.9 and 1.75 ± 0.4 cm2in groups I and II, respectively (p < 0.04). Additionally, at the end of the baselinr study, fractional shortening was significantly greater in group III and group IV (43 ± 5%) than in groups I and II (p < 0.01). In conclusion, syncope induced by head-up tilt is associated with vigorous myocardial contraction and a significant decrease in left ventricular end-systolic dimensions. This left ventricular hypercontractility may play an important role in the pathogenesis of syncope induced by head-up tilt.
Reducing the Risk of Sudden Death in Heart Failure With β-Blockers

Abstract Background Heart failure (HF) is a serious cardiovascular syndrome that affects nearly 5 million people in the United States. A review of clinical data demonstrates that sudden cardiac death (SCD) accounts for approximately one-third of all HF deaths. This fatal outcome typically involves an unexpected electrical event leading to sustained cardiac arrhythmias resulting in cardiovascular collapse. Methods and Results A systematic review of the literature was performed to serve as the basis for this review. Factors contributing directly to incidence of SCD in the HF population may include significant remodeling of the left ventricle (hypertrophy, dilation, and fibrosis) in addition to increased sympathetic activation. Using specific therapies to limit these mechanisms are beneficial in the HF patient by preventing SCD. β-blockers play a key role in the prevention of SCD for patients with HF by limiting the effects of circulating norepinephrine and by reducing left ventricular remodeling. Conclusions This review outlines the potential mechanisms and contributing factors of SCD in patients with HF and the impact of β-blocker usage in the prevention of this fatal outcome for this growing patient population.
Coagulopathy Does Not Protect Against Venous Thromboembolism in Hospitalized Patients With Chronic Liver Disease

Background It is uncertain whether pathologically prolonged international normalized ratio (INR) seen in chronic liver disease (CLD) protects against venous thromboembolism (VTE). Previous studies reported VTE incidence of 0.5% to 1.9% in patients with CLD. We sought to evaluate VTE incidence among hospitalized patients with CLD according to INR levels. Methods This was a retrospective cohort study performed at a tertiary university hospital. We included all adult patients admitted with a primary diagnosis of CLD over a 7-year period. The primary outcome was the development of VTE during hospital stay. Patients were divided into quartiles according to their highest admission INR. VTE events and prophylaxis rates were compared among INR quartiles. Results During the allotted 7-year period, we included 190 patients. Of these, 12 developed VTE events, yielding a VTE incidence of 6.3%. There was no significant difference in the incidence of VTE between INR quartiles. Hospital mortality rates were higher in the higher INR quartiles than in the lower ones (P Conclusions An elevated INR in the setting of CLD does not appear to protect against the development of hospital-acquired VTE. The notion that "auto-anticoagulation" protects against VTE is unfounded. Use of DVT prophylaxis was extremely low in this population.
Power and persuasion: Nonviolent strategies to influence state security forces in Serbia (2000) and Ukraine (2004)

Abstract During the Serbian Otpor movement to oust Milosevic (2000) and the Ukrainian “Orange Revolution” (2004), the organizers developed explicit strategies to increase the costs of repression and to undermine the willingness of state security forces to engage in violent acts against them. By employing varying combinations of persuasion and deterrence tailored to the particular institutions they were addressing, the movements were able to successfully avoid a major crackdown.
Principles of Geochemistry

Geochemistry is one of those broad fields of study that is difficult to define to the satisfaction of all those who work in it. One widely accepted definition is the traditional Goldschmidtian approach that considers geochemistry to be a study of the geological and chemical controls on the distribution of the elements within the earth. This is the definition of geochemistry that is implicit in the approach taken by this book. On the whole, the book does a commendable job in treating this aspect of geochemistry, although the quality of coverage for various subjects is far from uniform. For instance, the treatment of the distribution of major and trace elements caused by igneous processes is well organized and clearly written, whereas the chapter on metamorphic processes can only be described as excoriable. This is the fourth edition of a book that was first published in 1966, and, considering that the text deals with such long-dead issues as stress and antistress minerals, it seems to this reviewer that the chapter on metamorphic processes has not been updated since that date.
Effects of early angiotensin-converting enzyme inhibition on cardiac gene expression after acute myocardial infarction.

Background—ACE inhibition after myocardial infarction (MI) has been shown to have beneficial effects on cardiac anatomy and function. The purpose of this study was to examine the effects of ACE inhibition on cardiac gene expression after MI. Methods and Results—Rats were randomized to receive captopril or no treatment 1 day after MI. Eight weeks later, cardiac function and hemodynamics were measured by use of indwelling catheters and perivascular flow probes. Myocardial gene expression was assessed with DNA microarrays and real-time reverse transcription–polymerase chain reaction. The ratios of heart and left ventricular weights to body weight were significantly increased by MI and normalized by captopril. Cardiac index and stroke volume index were lower in the untreated MI group than in sham controls but were normal in the MI+captopril group. Thirty-seven genes were found to be differentially expressed between the untreated MI group and sham controls; 31 were induced and 6 repressed. Captopril partially ...
Fact and fiction in yield modeling

Abstract The history of yield modeling is reviewed and some of the theories are evaluated. The development of simplistic yield models is described and compared with Murphy's theory. The more accurate models used for characterization and control of fabricators are also discussed. In addition, the methodology of dealing with photolithographic defects is explored. Some of the finer details of the historical development of this topic have often been overlooked, but are treated here in detail with references to the earlier work.
Stochastic modeling of facility security-systems for analytical solutions

Abstract In this paper the author presents a modeling approach which makes use of conventional systems engineering techniques; namely, system block diagrams and networks where the transfer functions are expressed in the complex domain using Laplace transforms. Transit times, and times for the intruders and the responding guard force to overcome barriers, are both static and dynamic; the times are either deterministic or probabilistic variables obeying different and mixed probability laws. The solution methods are analytical, yielding measures of effectiveness of the security system. Modeling and solutions are presented for two cases. One case is for the simplified scenario where the reliability, sensitivity and response times of the sensors are assumed to be independent of time. The other is for the generalized case where sensor response times are time dependent and where the guard force encounters multiple barriers when attempting to intercept the intruders.
POISSON STRUCTURES OF SUPERCONDUCTORS

Abstract We present Poisson structures for a hamiltonian, time-dependent , formulation of the Ginzburg-Landau theory of superconductor dynamics. The resulting equations are seen to be related to the London theory. Application of irreversible thermodynamics leads to an extension of these equations to the dissipative case.
1042. Tracking and Gene Expression Profile of Bone Marrow Mesenchymal Stem Cells Injected into Pig Myocardium by Magnetic Resonance Imaging and Laser-Capture Microdissection

Bone marrow mesenchymal stem cells (MSCs) have been used for myocardial regeneration. The fate of injected cells and mechanism of their therapeutic benefits are unclear and cardiomyocytic differentiation is limited. We examined the gene expression of autologous MSCs injected into pig myocardium to assess the biologicprocesses involved.
Mobile Association in a Heterogeneous Network

In the future heterogeneous wireless networks with a mixed deployment of macro BS and micro relay stations, different nodes will compete for the same radio resources for providing mobile services. This poses great challenges to radio resource management and coordination. One critical step to achieve the optimal radio resource usage is for the mobiles to connect to the access nodes that provide the best radio conditions to them. This paper proposes a new mobile association mechanism in such a heterogeneous environment that aims to provide the best service to the mobiles on both uplink and downlink while minimizing the interference level. The simulation results show that with the proposed scheme the mobile performance shall be improved compared with the traditional mobile association schemes.
Impact of Supply Learning When Suppliers Are Unreliable

Dual sourcing and inventory are two prevalent and widely studied strategies firms use to manage yield risk. A pervasive but implicit assumption in the literature is that a firm knows its suppliers' yield distributions with certainty. This is a strong assumption in many circumstances. A firm is more likely to have a forecast of a supplier's yield distribution and to update that forecast based on its experiences with the supplier. We introduce and analyze a Bayesian model of “supply learning” (i.e., distribution updating) and investigate how supply learning influences both sourcing and inventory strategies in dual-sourcing and single-sourcing models, respectively. In the case of Bernoulli all-or-nothing yield distributions, we completely characterize the firm's optimal sourcing and inventory decisions for the supply-learning model. Among other results, we prove that for a given expected supplier reliability (i.e., the mean of the firm's forecast for the probability of successful delivery) an increase in the reliability forecast uncertainty increases the attractiveness of a supplier, but it reduces the firm's desire to invest in inventory to protect against future supply failures. We extend our analysis to allow for general yield distributions, multiple sourcing (i.e., more than two suppliers), and inventory carryover in the dual-sourcing model.
Commentary: Evolution and sociology

Abstract Religious fundamentalists have been engaged in a 70-year political battle against evolutionary theory. While the battle has focused largely on the science curriculum in our primary and secondary schools, sociology has a stake in this battle. I argue that sociology should do more than support science curricula against attempts to include religious doctrines. It is time for sociology to embrace the theory of evolution in its own curriculum.
Periprosthetic fractures about the knee: Clinical pearls and pitfalls

Abstract As the average age of our population advances, the demand for total knee arthroplasty (TKA) increases. Additionally, the average age of patients receiving TKA is decreasing, further augmenting the size of the recipient population and the patients' functional demand on the implants. Concurrent with the growth of TKA performed is an increase in the overall number of adverse outcomes following TKA, one of which includes periprosthetic fracture. These injuries can be challenging to treat and, if not addressed properly, may contribute to accelerated prosthetic failure. Furthermore, these injuries impart a significant mortality risk, higher than elective arthroplasty or fracture of a native distal femur. This article will serve as a review of periprosthetic fractures of the distal femur above a TKA and the authors' preferred management strategies with respect to fracture location and implant type.
TEACHING STANDARD ENGLISH IN THE THIRD GRADE: CLASSROOM FUNCTIONS OF LANGUAGE1

This study is based on the examination of twenty lessons of about 20 minutes duration each. Ten of the lessons dealt with teaching standard English negation (lesson 1), ten of the lessons dealt with the teaching of standard English past tense formation (lesson 2). The pupils were third graders, predominantly speakers of Vernacular Black English (VBE). The purpose of the study was (I) to determine the distribution of the main classroom discourse functions (e.g., Informing, Eliciting, Evaluating, Replying) throughout the lessons and (2) to examine the incidence of use of VBE English grammar throughout the lessons. On the basis of pre -and post-tests given to pupils, each group of ten lessons was also subdivided into five high-achieving and five low-achieving teaching performances. High and low achieving performances were compared on selected distribution of discourse function moves. Transcriptions of the lessons were segmented into T-units (main-clause + possible subordinate clause) which were in turn assigned to discourse function categories. As expected, Eliciting, Informing, Evaluating were by far the most frequent discourse categories used by teachers, while the category of Replying represented nearly the only discourse function (over 90%) utilized by pupils. VBE was used only occasionally by the teachers—either spontaneously or for the purpose of demonstrating a point of grammar (3.3% of moves in lesson 1, 0.35% of moves in lesson 2). Use of VBE by pupils—either spontaneously or indrills-was also relatively scarce (7.3% in lesson I, I .2% in lesson 2). Only one of the comparisons of “high” and “low” achieving teacher performances indicates a significant difference between the two groups. In lesson I the high achieving teachers devoted higher proportions of their moves to Elicits than the low achieving ones. An examination of the lesson transcripts suggests that this fact may be explained by the “1ow” teachers’ tendency to devote much of their lessons to lnformsdealing with a clarification of the concept of negation. This clarification, however, may have been superfluous and was. at any rate, unrelated to the criterion test. I t is suggested that analysis of discourse functions may be a useful approach to the study of teaching efficiency if it is related to meaning and the concepts of a specific lesson.
Splenectomy for Trauma

Splenic injury with significant damage to the hilum or unstable patient or multiple other injuries or failed splenic salvage.
Chromosome-wide SNPs reveal an ancient origin for Plasmodium falciparum

The Malaria's Eve hypothesis, proposing a severe recent population bottleneck (about 3,000–5,000 years ago) of the human malaria parasite Plasmodium falciparum, has prompted a debate about the origin and evolution of the parasite1,2,3,4,5,6. The hypothesis implies that the parasite population is relatively homogeneous, favouring malaria control measures. Other studies, however, suggested an ancient origin and large effective population size5,7,8,9,10. To test the hypothesis, we analysed single nucleotide polymorphisms (SNPs) from 204 genes on chromosome 3 of P. falciparum. We have identified 403 polymorphic sites, including 238 SNPs and 165 microsatellites, from five parasite clones, establishing chromosome-wide haplotypes and a dense map with one polymorphic marker per ∼2.3 kilobases. On the basis of synonymous SNPs and non-coding SNPs, we estimate the time to the most recent common ancestor to be ∼100,000–180,000 years, significantly older than the proposed bottleneck. Our estimated divergence time coincides approximately with the start of human population expansion11, and is consistent with a genetically complex organism able to evade host immunity and other antimalarial efforts.
Chronic administration of hydroxylamine and derivatives in mice.

SummaryLong-term administration of hydroxylamine, methoxyamine, or hydroxyurea to Swiss-Webster mice did not cause tumor formation. Hydroxylamine inhibited spontaneous formation of mammary tumors in female C3H mice. The principal toxic effects of hydroxylamine were anemia, splenomegaly and bone formation in the spleen.The authors appreciate the assistance of Mr. Gerome McDowell and Miss J. Zuefle in various phases of the experiments.