cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of reserpine on the reactivity of atrial and ventricular pacemakers to quinidine.

AN antagonism of the cardiac actions of quinidine by exogenous catecholamines has been demonstrated1–3. It is likely, therefore, that cardiac catecholamines also antagonize the depressant action of quinidine. To test this possibility, the effect of reserpine pretreatment on the action of quinidine in isolated cat hearts with complete heart block was investigated.
Quality of currently available methodology for monitoring viruses in the environment

Abstract A variety of methods have been proposed, developed, and evaluated for detecting viruses, especially human enteric viruses, in water, wastewater, and other environmental samples, and continued developments and improvements have led to simpler and more reliable methodology. However, the use of currently available methods is still limited primarily to special circumstances, such as investigation of waterborne disease outbreaks, research studies on virus reductions by water and wastewater treatment processes and systems, especially reuse systems, and research monitoring and surveying of natural and treated waters. Widespread and routine virus monitoring is still not possible due to technical limitations and deficiencies of present detection methods and their relatively high cost. Although continued development of new methods and further improvement of existing methods is desirable, it is perhaps more important that current methods be systematically evaluated in carefully designed collaborative (round-robin) studies and quality assurance tests. Until virus detection methods are further improved and systematically evaluated, the establishment of virus standards for such materials as water and edible shellfish requiring routine monitoring appears to be unjustified.
Compensating victims of violent crime

Nationally only a small percentage of violent crime victims file claims or receive awards from violent crime compensation boards. Using data generated in a national study of the boards, the article explores some of the reasons why this is believed to be so. Proportionately, there are significant differences among the states in the number of claims filed and awards made to violent crime victims; also, there are significant differences among the states between the awards to claim ratios.
Economic and Social Thinking at the UN in Historical Perspective

This article begins to examine the history of economic and social ideas launched or nurtured by the United Nations (UN). In 1999, the United Nations Intellectual History Project was initiated, to analyse the UN as an intellectual actor, and to shed light on the role of the UN system in creating knowledge and in influencing international policy-making: this article is based on the first five books and the oral histories from that Project. The starting point is that ideas may be the most important legacy of the UN for human rights, economic and social development, as well as for peace and security. For the authors, this ‘intellectual history’ provides a way to explore the origins of particular ideas; trace their course within institutions, scholarship, and discourse; and in some cases evaluate the impact of ideas on policy and action.
The microstructure of type 304 stainless steel implanted with titanium and carbon and its relation to friction and wear tests

Abstract We have used transmission electron microscopy to examine the microstructure of type 304 stainless steel which was ion implanted with high doses (2 × 1017 atoms cm-2 of titanium and carbon. We find that the resulting surface alloy is an amorphous phase similar to that observed when pure iron is identically implanted. This result is important for identifying the mechanisms by which the coefficient of friction and the wear deoth are reduced in unlubricated pin-on-disc tests of type 304 stainless steel implanted with titanium and carbon. We have also examined the effect of temperature on the amorphous alloy during annealing in the microscope. We find that devitrification begins after 15 min at 500 °C and that the alloy fully crystallizes into f.c.c., b.c.c. and TiC phases after 15 min at 650 °C. A comparison of mechanical test results from devitrified specimens with results from amorphous specimens demonstrates that the reduction in the coefficient of friction correlates with the presence of the amorphous layer, whereas the reduction in the wear depth is obtained for both amorphous and crystalline alloys.
Multiderivative Runge-Kutta processes for two-point boundary value problems

A class of finite difference schemes for the solution of a nonlinear system of first order differential equations with two point boundary conditions which shares properties with Runge-Kutta processes and gap schemes is discussed. The order conditions for the coefficients of these processes, techniques for reducing these order conditions in number and the symmetry conditions are given. A symmetricA-stable eight order process which has second, fourth and sixth orderA-stable processes embedded in it is given as an example.
Growing readers : A hierarchical linear model of children's reading growth during the first 2 years of school

Using the first 4 waves of data from the Early Childhood Longitudinal Study-Kindergarten cohort (ECLS-K), this piecewise 3-level (time-student-school) growth-curve model provides a portrait of students' reading growth over the first 2 years of school. On average, students make much greater reading gains in 1st grade than they do in kindergarten. First-grade monthly reading growth averages 2.65 points per month, whereas kindergarteners make approximately 1.67 points of reading growth per month. Student-level variables (including socioeconomic status, ethnicity, kindergarten entry age, and gender) were better able to explain between-schools variability in students' initial reading scores and students' reading growth than school-level variables (percentage of minority students, percentage of free-lunch students, and sector). Although socioeconomic status had a minimal impact on reading growth while school was in session, it had a larger impact on summer reading growth. These results suggest that between-schools differences in achievement are largely explained by the differences in school clientele, rather than differences in instruction or resource allocation. These results also underscore the potential importance of preschool and summer programs for low-socioeconomic status children.
Thoracoabdominal Aortic Aneurysm Repair in Patients with Single Kidney

Data were analyzed from 581 consecutive cases of thoracoabdominal aortic aneurysm (TAAA) repairs. Preoperatively, 32 patients (6%) had only one functioning kidney (single-kidney group), and 549 patients (94%) had tow functioning kidneys (reference group). The patients’ mean age was higher in the reference group (64.9 years, range: 21-85) than in the single-kidney group (63.2 years, range: 38-79); p 0.05. Renal artery endarterectomy or bypass ipsilateral to functioning kidneys was performed on 18 patients (56%) in the single-kidney group and 68 patients (12%) in the reference group; p 0.05. There was no difference in the operative mortality (9% versus 7%) and the incidence of paraplegia/paraparesis (6% versus 5%) between the single-kidney group and the reference group; p > 0.05. Postoperatively, new onset renal insufficiency developed in 10 patients (31%) in the single-kidney group, and 58 patients (11%) in the reference group; p 0.05). TAAA repair in patients with one functioning kidney can be performed safely. Postoperative renal insufficiency can be managed successfully in the majority of patients.
Cushing Syndrome: Establishing a Timely Diagnosis ☆

The Pediatric Endocrinology Nursing Society (PENS) is committed to the development and advancement of nurses in the art and science of pediatric endocrinology nursing and to improve the care of all children with endocrine disorders through the education of the pediatric healthcare community. To aid in achieving that goal, the purpose of A 12-year-old Hispanic female presents to the local emergency room with seizures and severe hypertension. Over the past year, she gained 15 kilograms, with no changes in her appetite or level of physical activity, yet she stopped growing in height. Her BMI increased from 21.9 to 29 kg/m2. She was recently diagnosed with type 2 diabetes mellitus and was treated with metformin and diet modification. Her mother noticed that she was more impatient and irritable in the last 4–5 months. Significant findings on her physical exam included severe acne (face, chest, and back); acanthosis nigricans; hirsutism; wide purple striae on legs, abdomen, trunk; facial plethora; fat pads in supraclavicular, temporal, and dorsocervical areas; scattered petechiae on arms and shins; proximal muscle weakness; tinea versicolor; candida albicans; Tanner V pubic hair and Tanner II breast development. Her blood pressure remained N 90% for age–height, even with treatment with three antihypertensive medications. Alarmed by the severity of her hypertension along with concomitant development of rapid onset weight gain, diabetes, and numerous physical changes in a young girl, the emergency room doctor suspected Cushing syndrome and referred the child to a pediatric endocrinologist. Following is a brief overview of Cushing syndrome and the integral role of the pediatric nurse in the care of these children.
Acute traumatic subdural hematoma: current mortality and functional outcomes in adult patients at a Level I trauma center.

While subdural hematomas (SDHs) are a common form of traumatic brain injury, the outcomes of adult patients with SDH are not well described in the literature. Most previous studies of SDH included patients who received care more than 20 years ago1–4 and lack information on medical complications and functional status.5,6 All are limited by small sample size (i.e., n = 47 to 308).1–8 We had the unique opportunity to study a large cohort of patients treated for SDH in a Level I trauma center with prospectively collected, standardized information on clinical characteristics, hospital course, functional outcomes, and mortality. We hypothesized that current mortality rates are lower than previously reported. To further evaluate this, we specifically compared patients undergoing surgical evacuation with those without evacuation, with the expectation that those undergoing surgical evacuation represent a subset with increased risk for poor outcomes.
Role of Product Entry and Exit on the Attraction Effect

The attraction effect illustrates a violation of the regularity assumption in consumer choice. This effect increases the share of a target brand, relative to a competitor, when a third alternative is added to the choice set such that the target dominates the third alternative completely but the competitor does not. The effect has important marketing implications for design and presentation of choice sets to consumers. This paper studies the influence of sequential product entry and exit on the attraction effect; specifically, it focuses on the differences among simultaneous entry, delayed product entry, and product exit. Using two experiments, the paper shows that even sequential actions, such as entry or exit of products, predictably produce the attraction effect.
Mass Point Leak Rate Technique with Uncertainty Analysis

The mass point leak rate technique is often the methodology of choice for quantifying leak rates as it uses simple elementary measurements, applies to gas systems of low mass, proves effective for low leak rates, and does not rely on test-gas conversions. In this methodology, a number of instantaneous mass measurements are calculated through samples of volume, pressure, gas composition, and temperature measurements over time. A regression analysis of the corresponding mass-time sample set yields the leak rate of the system. A detailed uncertainty analysis is paramount for a complete, experimental characterization of the leak rate and previously was not fully implemented in the mass point leak rate method. Recent advancements in regression uncertainty analysis by propagation of errors afford the ability to quantify the uncertainty with estimates of covariance in the regression results. The mass point leak rate technique with the associated detailed measurement uncertainty analysis offers the ability to qua...
Repair of long gap esophageal atresia without anastomosis.

Abstract Background/Purpose Repair of long gap esophageal atresia represents a challenge. Several different techniques may be used. We describe 5 cases of long gap esophageal atresia managed successfully with suture approximation without anastomosis. Methods Retrospective review identified 5 newborns (4 males; 1 female) with long gap esophageal atresia treated with suture approximation and subsequent endoscopic and fluoroscopic placement of string for guided dilatations. Three babies had esophageal atresia without fistula, and 2 had the common type with proximal atresia and distal tracheoesophageal fistula. The babies with pure esophageal atresia had delayed repair, and those with the common type had repair 2 days after birth. All had a gastrostomy for feedings. Results All 5 babies recovered uneventfully. Three babies had spontaneous fistulization that allowed easy placement of guide wire and string. Two other babies required endoscopic and fluoroscopic combined fistula creation bypassing a long needle from the upper pouch to the lower one. Initially, all had string-guided dilatations that were subsequently converted to balloon dilatations. All babies had a functioning esophagus and did not need any further surgical intervention. An average of 8 postoperative dilatations were needed. Conclusions The baby's own functional esophagus is superior to any esophageal replacement. Familiarity with different techniques to preserve it is therefore important. Suture approximation without anastomosis is a safe technique that can be applied to long gap esophageal atresia. The downside of this technique is a prolonged hospital stay, multiple dilatations, prolonged fasting, and therapy to learn to eat orally.
Intrinsic and extrinsic contributions to heavy tails in visual foraging

Eyes move over visual scenes to gather visual information. Studies have found heavy-tailed distributions in measures of eye movements during visual search, which raises questions about whether these distributions are pervasive to eye movements, and whether they arise from intrinsic or extrinsic factors. Three different measures of eye movement trajectories were examined during visual foraging of complex images, and all three were found to exhibit heavy tails: Spatial clustering of eye movements followed a power law distribution, saccade length distributions were lognormally distributed, and the speeds of slow, small amplitude movements occurring during fixations followed a 1/f spectral power law relation. Images were varied to test whether the spatial clustering of visual scene information is responsible for heavy tails in eye movements. Spatial clustering of eye movements and saccade length distributions were found to vary with image type and task demands, but no such effects were found for eye movement ...
Cocaine Users in Medical Practice: A Five-Year Follow-up

Prompted by the discontinuity between the number of estimated cocaine users in epidemiologic studies and the small number entering the substance abuse treatment system in the early 1980s, Weinstein et al. surveyed physicians practicing in a variety of specialties and found sizable numbers of cocaine-using patients being seen by physicians not in the substance abuse treatment system. Since the number of cocaine abusers has steadily increased during the decade, a 5-year follow-up of that research was conducted to determine if physicians in private practice have continued to see increasing numbers of cocaine-using patients. A survey of Philadelphia area physicians indicates that these physicians have continued to see growing numbers of cocaine-using patients, and that those numbers have increased dramatically. While an average of 0.61 patients per physician was noted in the early 1980s, by 1987 that value had increased over 200% to 1.84. Since physicians outside the traditional substance abuse system have co...
Cultural Organizing as Critical Praxis: Tamejavi Builds Immigrant Voice, Belonging, and Power

Established in 1998, the American Friends Service Committee’s Pan Valley Institute (PVI) is a popular education center located in Fresno, California. Since its inception, PVI has placed a high value on what immigrants bring with them to this country—their experiences, abilities, and cultural practices, which are often informed by prolonged and daily struggles against economic and social injustice. This article profiles PVI’s “cultural organizing” work that supports immigrant cultural leaders representing the Valley’s diverse populations. In conclusion, three contributions are highlighted that the Tamejavi approach brings to academic conversations about art as social practice.
Sputtered zinc selenide buffer layers for Cu(InGa)Se 2 substrate and superstrate solar cells

RF magnetron sputtered ZnSe was used as a Cd-free buffer layer in Cu(InGa)Se 2 solar cells. Devices in substrate configuration showed relatively low short circuit current compared to those with a CdS buffer layer. Cu(InGa)Se 2 with various Ga contents were tested and J sc improvement was observed with an increase in Ga/III ratio. Temperature dependent JV measurements showed that ZnSe/Cu(InGa)Se 2 formed a spike conduction band offset at the interface, acting as an electron blocking barrier. The barrier height could be reduced by incorporating more Ga into Cu(InGa)Se 2 . Superstrate Cu(InGa)Se 2 cells showed efficiencies less than 4%. SEM and XPS depth profiling revealed that ZnSe inter-diffused into Cu(InGa)Se 2 at high temperature absorber growth.
Flight Data for Boundary-Layer Transition at Hypersonic and Supersonic Speeds

Published e ight data for boundary-layer transition at hypersonic speeds are surveyed. The survey is limited to measurements reported in the open literature and carried out at hypersonic and high-supersonic speeds, on vehicles for which ablation is believed to be negligible or small. The emphasis is on work that may be suitable for validation of advanced transition-estimation methods that are based on simulation of the physical mechanisms, such as e N , the parabolized stability equations, and direct numerical simulations. Brief discussions are presented for each report. Known comparisons to the advanced simulation methods are also presented. Nomenclature Me = Mach number at the boundary-layer edge Res = Reynolds number at transition onset, based on arc length from the leading edge and local conditions at the boundary-layer edge ReT = Reynolds number at transition onset, based on arc length and conditions at the boundary-layer edge ReT/ft = unit Reynolds number per foot, at the boundary-layer edge at transition onset Reµ = Reynolds number at transition, usually onset, based on momentum thickness and conditions at the boundary-layer edge Te = temperature at the boundary-layer edge Tr = recovery temperature at the wall Tw = wall temperature xT = arc length to transition onset, from the nose µc = cone half-angle, deg
Shuttling and translocation of heterotrimeric G proteins and Ras

Heterotrimeric G proteins (αβγ) and Ras proteins are activated by cell-surface receptors that sense extracellular signals. Both sets of proteins were traditionally thought to be constrained to the plasma membrane and some intracellular membranes. Live-cell-imaging experiments have now shown that these proteins are mobile inside a cell, shuttling continually between the plasma membrane and intracellular membranes in the basal state, maintaining these proteins in dynamic equilibrium in different membrane compartments. Furthermore, on receptor activation, a family of G protein βγ subunits translocates rapidly and reversibly to the Golgi and endoplasmic reticulum enabling direct communication between the extracellular signal and intracellular membranes. A member of the Ras family has similarly been shown to translocate on activation. Although the impact of this unexpected intracellular movement of signaling proteins on cell physiology is likely to be distinct, there are striking similarities in the properties of these two families of signal-transducing proteins.
Quantum-Defect Electronegativity Scale for Nontransition Elements

We suggest that the Pauli-force model potential defines a new electronegativity scale consisting of explicit orbital components. These are determined algebraically from atomic spectral data. We find that these components distinguish quantitatively the most stable crystal structures of 34 nontransition elemental solids and $59{A}^{N}{B}^{8\ensuremath{-}N}$ binary compounds.
Allelopathic effects of juglone on germination and growth of several herbaceous and woody species

Laboratory experiments were conducted to determine juglone sensitivity of 16 species (Trifolium incarnatum, Coronilla varia, Vicia villosa, Lespedeza stipulacea, L. cuneata, Acer ginnala, Caragana arbor-escens, Elaegnus angustifolia, E. umbellata, Lonicera maackii, Quercus alba, Fraxinus americana, Liriodendron tulipifera, Alnus glutinosa, Pinus strobus, andP. sylvestris) being considered for mixed plantings withJugions nigra (black walnut). All species were sensitive to juglone, but seed germination and radicle elongation were less affected than shoot elongation and dry weight accumulation. Seed germination and radicle elongation were affected by juglone in 6 and 11 species, respectively, mainly by the higher concentrations (10−3 M and 10−4 M). Shoot elongation and dry weight accumulation of all species were affected by juglone; many species were sensitive to concentrations as low as 10−6 M. Seedlings of all species were severely wilted and eventually killed by 10−3 M juglone, and most were chlorotic and severely retarded by 10−4 M juglone. Seedlings inhibited by 10−6 M and 10−5 M juglone did not showany visible signs of injury. Based on the effects on seedling shoot elongation and dry weight accumulation, the five species found to be most sensitive to juglone were:Lonicera maackii, Lespedeza cuneata, Trifolium incarnatum, Alnus glutinosa, and Elaeagnus umbellata.
Determination of the properties of Mercury's magnetic field by the MESSENGER mission

Abstract The MESSENGER mission to Mercury, to be launched in 2004, will provide an opportunity to characterize Mercury's internal magnetic field during an orbital phase lasting one Earth year. To test the ability to determine the planetary dipole and higher-order moments from measurements by the spacecraft's fluxgate magnetometer, we simulate the observations along the spacecraft trajectory and recover the internal field characteristics from the simulated observations. The magnetic field inside Mercury's magnetosphere is assumed to consist of an intrinsic multipole component and an external contribution due to magnetospheric current systems described by a modified Tsyganenko 96 model. Under the axis-centered-dipole approximation without correction for the external field the moment strength is overestimated by ∼4% for a simulated dipole moment of 300 nT R M 3 , and the error depends strongly on the magnitude of the simulated moment, rising as the moment decreases. Correcting for the external field contributions can reduce the error in the dipole term to a lower limit of ∼1–2% without a solar wind monitor. Dipole and quadrupole terms, although highly correlated, are then distinguishable at the level equivalent to an error in the position of an offset dipole of a few tens of kilometers. Knowledge of the external magnetic field is therefore the primary limiting factor in extracting reliable knowledge of the structure of Mercury's magnetic field from the MESSENGER observations.
A new weather generator based on spectral properties of surface air temperatures

We present a new weather generator, which simulates daily precipitation occurrence and daily maximum and minimum air temperature. Precipitation occurrence is simulated with a two-state, second-order Markov process, while maximum and minimum daily temperatures are simulated using spectral methods. Data generated at nine stations in the Southeastern USA are then compared to: (1) observed station data, and (2) data generated by a variant of the commonly used autoregressive weather generator. Precipitation occurrence simulation is found to be excellent for our study region. Maximum and minimum temperatures generated using the spectral weather generator are found to be superior to those generated by the autoregressive weather generator in terms of means and variances across multiple timescales as well as the number of freeze events, skewness of temperature distributions, and the relationship between daily minimum and maximum air temperatures. Both weather generators are found to slightly underestimate interannual variability in all three generated variables.
Measurements of X-Ray Lattice Constant, Thermal Expansivity, and Isothermal Compressibility of Argon Crystals

Crystals of 99.998% purity argon were prepared by directional solidification of the liquid. The x-ray lattice constant was measured by means of a rotating-camera method, and the volume coefficient of thermal expansion was determined over the range 2.3 to 83.2\ifmmode^\circ\else\textdegree\fi{}K with a precision of about 5 ppm ${\mathrm{deg}}^{\ensuremath{-}1}$. The lattice constant extrapolated to 0\ifmmode^\circ\else\textdegree\fi{}K is 5.30017\ifmmode\pm\else\textpm\fi{}0.00008 kxu. X-ray diffraction was also used to obtain a value for the isothermal compressibility at 4.25\ifmmode^\circ\else\textdegree\fi{}K of (3.75\ifmmode\pm\else\textpm\fi{}0.05)\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}11}$ ${\mathrm{cm}}^{2}$ ${\mathrm{dyn}}^{\ensuremath{-}1}$. A critical synthesis of existing measurements of elastic-wave velocity and of isothermal compressibility is attempted because comparison of the present results with various theoretical models for crystalline argon is limited by the inaccuracies of elastic data. A set of compressibility values is adopted and new values for several thermodynamic functions of argon are compiled. The observed temperature variations of the Gr\"uneisen parameter and of the Debye temperature are compared with several lattice-dynamical models.
Rapid Toxicity Assessment Using Ingestion Rate of Cladocerans and Ciliates

Ingestion rate of suspension feeding zooplankton is a useful endpoint for rapid toxicity assessment. Methods are presented for quantifying ingestion rate in single Ceriodaphnia dubia, Paramecium aurelia, and Brachionus plicatilis, using fluorescent beads and image analysis. Test organisms are exposed to toxicants for one hour, then allowed to feed on 2 μm fluorescent beads for 3 minutes. Toxicants reduced ingestion rate in a dose-dependent manner, permitting the calculation of NOECs. The NOECs for 7 toxicants are presented for the 3 species as well as comparative toxicity of pore water samples from 13 urban creeks. The sensitivity of the 1-h C. dubia ingestion rate test was compared to 48-h LC50 and 7-d reproductive tests for 2 and 4 compounds, respectively. The ingestion test was within a factor of 2 for 3 of the comparisons, but >8 times less sensitive for the other 3 comparisons. For B. plicatilis, 1-h ingestion rate NOEC was lower than the 24-h LC50s for 4 of the 5 compounds tested. The rotifer 48-h reproductive test was a more sensitive endpoint for 3 of 4 compounds. These methods are simple, rapid, and inexpensive, permitting several species to be incorporated into a test battery.
Pain Management in the Last Six Months of Life Among Women Who Died of Ovarian Cancer

Abstract Previous studies indicate that the symptoms of many dying cancer patients are undertreated and many suffer unnecessary pain. We obtained data retrospectively from three large health maintenance organizations, and examined the analgesic drug therapies received in the last six months of life by women who died of ovarian cancer between 1995 and 2000. Subjects were identified through cancer registries and administrative data. Outpatient medications used during the final six months of life were obtained from pharmacy databases. Pain information was obtained from medical charts. We categorized each medication based on the World Health Organization classification for pain management (mild, moderate, or intense). Of the 421 women, only 64 (15%) had no mention of pain in their charts. The use of medications typically prescribed for moderate to severe pain (“high intensity” drugs) increased as women approached death. At 5–6 months before death, 55% of women were either on no pain medication or medication generally used for mild pain; only 9% were using the highest intensity regimen. The percentage on the highest intensity regimen (drugs generally used for severe pain) increased to 22% at 3–4 months before death and 54% at 1–2 months. Older women (70 or older) were less likely to be prescribed the highest intensity medication than those under age 70 (44% vs. 70%, P
Autosomal dominant polycystic kidney disease in childhood: a longitudinal study.

Autosomal dominant polycystic kidney disease in childhood: A longitudinal study. One hundred fifty–four children aged eighteen years or younger from 83 families with autosomal–dominant polycystic kidney disease were studied by ultrasonography or excretory urography. Twenty–three children had bilateral renal involvement with at least five cysts (ADPKD), 28 children were classified as suspicious (SADPKD), and 103 children had no renal involvement (NADPKD) detected by ultrasound. Seventy–four percent of the ADPKD children had signs or symptoms compatible with the diagnosis of ADPKD, compared to 34% of the NADPKD and 36% of the SADPKD children (both P
Commercial-Off-The-Shelf Selection Process

Abstract:This article presents a Commercial-Off-The-Shelf (COTS) evaluation and selection process that utilizes a weighted scoring model to facilitate the comparison of COTS components relative to a number of pre-established evaluation criteria. The application of a COTS evaluation methodology will enable project teams responsible for designing complex systems to take advantage of potential economic leverage and performance advantages COTS technology presents. More importantly, this approach provides a mechanism for careful evaluation of the candidate COTS components to ensure engineers developing COTS-intensive systems give appropriate consideration to critical COTS attributes such as operational requirements, risk, cost, technology maturity, and supplier viability.
Structure and dynamics of pentaglycyl bridges in the cell walls of Staphylococcus aureus by 13C-15N REDOR NMR.

Whole cells and cell-wall fractions of Staphylococcus aureus have been labeled by various combinations of [1-13C]glycine, [15N]glycine, l-[6-13C]lysine, l-[6-15N]lysine, d-[1-13C]alanine, and d-[15...
Human proton/oligopeptide transporter (POT) genes: Identification of putative human genes using bioinformatics

Purpose: The proton-dependent oligopeptide transporters (POT) gene family currently consists of ∼70 cloned cDNAs derived from diverse organisms. In mammals, two genes encoding peptide transporters, PepT1 and PepT2 have been cloned in several species including humans, in addition to a rat histidine/peptide transporter (rPHT1). Because the Candida elegans genome contains five putative POT genes, we searched the available protein and nucleic acid databases for additional mammalian/human POT genes, using iterative BLAST runs and the human expressed sequence tags (EST) database. The apparent human orthologue of rPHT1 (expression largely confined to rat brain and retina) was represented by numerous ESTs originating from many tissues. Assembly of these ESTs resulted in a contiguous sequence covering ∼95% of the suspected coding region. The contig sequences and analyses revealed the presence of several possible splice variants of hPHT1. A second closely related human EST-contig displayed high identity to a recently cloned mouse cDNA encoding cyclic adenosine monophosphate (cAMP)-inducible 1 protein (gi:4580995). This contig served to identify a PAC clone containing deduced exons and introns of the likely human orthologue (termed hPHT2). Northern analyses with EST clones indicated that hPHT1 is primarily expressed in skeletal muscle and spleen, whereas hPHT2 is found in spleen, placenta, lung, leukocytes, and heart. These results suggest considerable complexity of the human POT gene family, with relevance to the absorption and distribution of cephalosporins and other peptoid drugs.
The effect of environment on high-temperature hold time fatigue behavior of annealed 2.25 pct Cr 1 pct Mo steel

Total strain control fatigue tests with a 120-second hold period at either peak compressive or tensile strain were conducted on annealed 2.25 pct Cr 1 pct Mo steel. Tests were performed at the total strain range of 1.0 pct at 500 °C or 600 °C in air, 1.3 Pa (10−2 torr) or 1.3 × 10−3 Pa (10−5 torr) vacuum. The nature of the hold and the environment affect fatigue life and surface crack patterns. A compressive hold is more deleterious than a tensile hold in high-temperature air, while the reverse is true in environments in which oxidation is limited. Observations of cracks at the surface and in cross section indicate that an oxidation-fatigue interaction accounts for the damaging effect of a compressive hold in air tests. In vacuum tests, creep damage has the opportunity to accumulate and causes the tension hold to exhibit the shortest fatigue lifetime.
A statistical comparison of Antarctic finds and modern falls: Mass frequency distributions and relative abundance by type

— The relative abundance of different compositional types and mass frequency distributions are presented for four meteorite samples (the modern falls, Antarctic finds, Yamato finds and Allan Hills Main Icefield finds). The modern falls sample represents continuous collection of a known number of falls over a short timespan, while the Antarctic samples represent a longer timespan and an unknown number of falls. The Allan Hills Main Icefield sample has many desirable collection characteristics indicating it best represents Antarctic meteorites. By retabulating the modern falls to create a sample with characteristics similar to those of the Allan Hills Main Icefield finds, we can directly compare the two. The mass frequency distributions of Antarctic samples exhibit a tail toward the larger sizes and thus differ from that of the modern falls (which approximates a normal curve). In general, normal and power law models prove to be inadequate to explain the observed mass frequency distributions, possibly because they fail to correctly account for atmospheric and collection effects. Non-parametric statistics show that it is unlikely that the two are good samples of a single steady-state meteoritic complex. In addition, there is an excess in numbers of small H chondrites in Allan Hills Main Icefield finds relative to modern falls which is not easy to explain given modern showerfall rates of occurrence. This supports the view that the delivery of meteoritic material to Earth might be variable over the short timescale represented by these samples.
Dopamine imaging markers and predictive mathematical models for progressive degeneration in Parkinson's disease.

Summary We conducted PET imaging studies of modulation of dopamine transporter function and MRS studies of neurochemicals in idiopathic primate Parkinson's disease (PD) model induced by long-term, low-dose administration of MPTP. MR spectra showed striking similarities of the control spectrum of the primate and human striatum as well as MPTP-treated primate (six months after cessation of MPTP), and Parkinson's disease patient striatum (68 year old male; Hoehn-Yahr scale II; 510 mg/d L-DOPA). The choline/creatine ratio was similar in the MPTP model and human parkinsonism, suggesting a possible glial abnormality. The progressive degeneration of dopamine re-uptake sites observed in our PD model can be expressed by a time dependent exponential equation N(t) = N0 exp (−(0.072 ± 0.016) t), where N0 represents intact entities (dopamine re-uptake sites before MPTP) and 0.072 per month is the rate of degeneration. When the signs of PD appear, N(t) is about 0.3–0.4 times N0. Interestingly, this biological degenerative phenomena has similar progression to that observed in cell survival theory. According to this theory and calculated degeneration rate, predictive models can be produced for regeneration and protective treatments.
AN INTERNATIONAL COMPARATIVE STUDY OF TOTAL HIP ARTHROPLASTY COST AND PRACTICE PATTERNS

Abstract The cost of total hip arthroplasty (THA) was assessed on a worldwide basis, with specific information obtained regarding implant type, cost, manufacturer, fixation method, as well as other clinical related practices. One hundred and ten orthopaedic surgeons representing 30 countries and 6 continents responded to the questionnaire. The average number of THAs per year per surgeon was 75 (range, 2–300). Surgeons reported using all cemented components in 35% of THAs at an average cost of $1,536 (U.S. dollars). Uncemented components were used in 31% at an average cost of $2,674, and hybrid reconstructions in 34% at an average cost of $2,114. Almost half (44%) of the respondents stated that the hospital negotiated the type and price of the implants. Most surgeons (80%) indicated they were under pressure to decrease the cost of THA and 68% were under pressure to reduce the length of patients' hospital stay. When asked for recommended ways to reduce costs, 30% stated that negotiating a reduced implant price from the supplier was the most important measure. On a worldwide basis, there is tremendous variation in the cost and availability of implants. The reported cost for identical implants from a single manufacturer can vary as much as 700%. The comments of those responding are similar to the findings of surgeons here in the United States regarding cost containment and the role of reducing the length of hospital stay as well as negotiating reduced prosthesis and supply costs. The orthopaedic surgeon's practice pattern is a major determinant of total costs.
Playing it Safe as a Novice Teacher: Implications for Programs for New Teachers

Prompted by the continuing attrition rate of novice teachers, this study examines 1st-year teachers’ needs in the context of a university-regional partnership sponsored support program for novice t...
Auger analysis of silver-glass interfaces☆

Abstract The effects of vacuum annealing at moderate temperatures (200°C) evaporated silver films on float glass were measured using Auger spectroscopy. Upon annealing, the silver/glass boundary region remained free of detectable impurities. Diffusion was found to occur to a minor extent but did not substantially broaden the silver/glass interface for short (1 h) annealing times. The diffusion coefficient of metallic silver in float glass was estimated from profile data to be less than 1 × 10−15 cm2/s at 200°C.
Pharmacokinetic and pharmacodynamic drug interactions in the treatment of attention-deficit hyperactivity disorder.

The psychostimulants methylphenidate, amphetamine and pemoline are among the most common medications used today in child and adolescent psychiatry for the treatment of patients with attention-deficit hyperactivity disorder. Frequently, these medications are used in combination with other medications on a short or long term basis. The present review examines psychostimulant pharmacology, summarises reported drug-drug interactions and explores underlying pharmacokinetic and pharmacodynamic considerations for interactions. A computerised search was undertaken using Medline (1966 to 2000) and Current Contents to provide the literature base for reports of drug-drug interactions involving psycho-stimulants. These leads were further cross-referenced for completeness of the survey. Methylphenidate appears to be more often implicated in pharmacokinetic interactions suggestive of possible metabolic inhibition, although the mechanisms still remain unclear. Amphetamine was more often involved in apparent pharmaco-dynamic interactions and could potentially be influenced by medications affecting cytochrome P450 (CYP) 2D6. No published reports of drug interactions involving pemoline were found. The α2-adrenergic agonists clonidine and guanfacine have been implicated in several interactions. Perhaps best documented is their antagonism by tricyclic antidepressants and phenothiazines. In additional, concurrent β-blocker use, or abrupt discontinuation, can lead to hypertensive response. Although there are few published well-controlled interaction studies with psycho-stimulants and α2-adrenergic agonists, it appears that these agents may be safely coadministered. The interactions of monoamine oxidase inhibitors with psycho-stimulants represent one of the few strict contraindications.
Role of ERCP in asymptomatic orthotopic liver transplant patients with abnormal liver enzymes.

Role of ERCP in asymptomatic orthotopic liver transplant patients with abnormal liver enzymes
Leadership styles and occupational stress among college athletic directors: the moderating effect of program goals.

Abstract The interaction between an individual's abilities and the perceived demands of the workplace appears to make a unique contribution to job-related stress above and beyond that of dispositional or situational factors alone (R. S. Lazarus, 1990). In the present study, the author evaluated this contention among 245 male intercollegiate athletic directors by assessing the combined influence of leadership style and program goals on occupational stress. Regression analyses revealed the presence of both significant main effects and interaction effects of leadership style and program goals in the prediction of emotional exhaustion, daily job stress, and personal accomplishment. Findings are discussed in terms of person–environment fit theory (J. R. P. French, R. D. Caplan, & R. V. Harrison, 1982) and the notion of perceived control within the occupational setting.
Supraesophageal complications of gastroesophageal reflux.

Supraesophageal complications of GERD have become more commonly recognized or suspected by physicians. However, the direct association between these complications and GERD has often been difficult, if not impossible, to establish. Furthermore, the majority of patients with suspected supraesophageal complications of GERD do not have either the characteristic symptoms of heartburn and regurgitation or the definitive findings of esophageal inflammation, which would help reinforce the suspicion of a connection between the supraesophageal complications and GERD. Frequent acid reflux has been shown in patients with various bron-chopulmonary, laryngopharyngeal, or oral cavity disorders. GERD is one of the most common gastrointestinal complaints in the population. It is possible that the supraesophageal problems and acid reflux are mutually independent disorders that occur in the same person. The suspected mechanisms of GERD-related supraesophageal complications appear to be directed through two pathways: by a vagal reflex between the esophagus and tracheobronchial tree triggered by acid reflux or by microaspiration that causes contact damage to mucosal surfaces. The most useful diagnostic modality available to the clinician to aid in the diagnosis of supraesophageal GERD complications is the ambulatory pH recording technique. However, the sensitivity and specificity of this test for recording esophageal or pharyngeal acid reflux events has been critically challenged. Despite the many clinical studies that support the theory that GER has a role in suspected supraesophageal complications, only 1 long-term prospective controlled study of a large group of patients with asthma has shown the positive effects of the elimination of acid reflux. With the focus now on "outcomes medicine," there is a serious need for appropriately designed, controlled studies to answer the many questions surrounding a cause-and-effect association between acid reflux and supraesophageal disorders. Because of the lack of convincing proof between acid reflux and suspected supraesophageal complications, the physician must resort to an intent-to-treat strategy as both a primary therapy and a diagnostic trial. High-dose PPI therapy for prolonged periods is the recognized conservative therapy. Operative therapy (i.e., fundoplication operation) is the procedure of choice when overt regurgitation occurs or when medical therapy, although successful, is not practical for long periods. Controlled, well-designed clinical trials and more sophisticated techniques to measure and quantify acid reflux are crucial in the future to help determine which patients with suspected supraesophageal complications actually have acid reflux as a primary cause. The medical community needs to be alerted to the possibility of an association between GERD and supra-esophageal complications so that patients with a GERD-related complication will be recognized and effectively treated.
Initiation and progression of mechanical damage in the intervertebral disc under cyclic loading using continuum damage mechanics methodology: A finite element study

It is difficult to study the breakdown of disc tissue over several years of exposure to bending and lifting by experimental methods. There is also no finite element model that elucidates the failure mechanism due to repetitive loading of the lumbar motion segment. The aim of this study was to refine an already validated poro-elastic finite element model of lumbar motion segment to investigate the initiation and progression of mechanical damage in the disc under simple and complex cyclic loading conditions. Continuum damage mechanics methodology was incorporated into the finite element model to track the damage accumulation in the annulus in response to the repetitive loading. The analyses showed that the damage initiated at the posterior inner annulus adjacent to the endplates and propagated outwards towards its periphery under all loading conditions simulated. The damage accumulated preferentially in the posterior region of the annulus. The analyses also showed that the disc failure is unlikely to happen with repetitive bending in the absence of compressive load. Compressive cyclic loading with low peak load magnitude also did not create the failure of the disc. The finite element model results were consistent with the experimental and clinical observations in terms of the region of failure, magnitude of applied loads and the number of load cycles survived.