cssi/SciSciGPT-SciSciNet huggingface dataset:
Trends in Sunscreen Use Among US Middle and High School Students, 2007-2019.

OBJECTIVE The purpose of this project is to analyze trends in sunscreen usage among middle and high school students from the Centers of Disease Control's National Youth Risk Behavior Surveys (YRBS) from the years 2007 to 2019. METHODS Data from the 2007-2019 National YRBS were analyzed. YRBS is a cross-sectional survey of health risk behaviors among middle and high school students (grades 6-12) in the United States. Students were asked questions regarding sunscreen usage and demographic information, including age, race/ethnicity, and gender. RESULTS From 2007 to 2019, the average mean sunscreen usage for all students increased by 4% between every consecutive year studied. Mean sunscreen usage among all racial groups studied, other than Native Hawaiian or Other Pacific Islanders, increased. Females were 92.7% more likely to use sunscreen than males each year. The mean sunscreen usage decreased by 5% with an increase in a student's age. CONCLUSIONS Though overall sunscreen use in adolescents increased over the time period from 2007 to 2019, sunscreen use still remains limited due to a variety of factors possibly including cost, tanning, and different socio-cultural perceptions of sunscreen.
Eddy Current Probe Performance Variability

Eddy current testing is used extensively by the Air Force for nondestructive inspection of many aircraft structural components. Although the reliability and consistency of inspections depends to a large extent on the characteristics of the eddy current probes used, no adequate specifications or certification methods presently exist for assuring probe performance. Because of the variability in probe performance, a need exists for establishing a means to control probe performance characteristics which will eventually lead to improved test results.
Heavy Cigarette Smoking and Aggressive Bladder Cancer at Initial Presentation.

Objective To identify the impact of smoking intensity on tumor characteristics at the time of initial bladder cancer diagnosis. Methods We retrospectively reviewed our institution's prospective database of patients diagnosed with bladder cancer from 1987 to 2009. Only patients with urothelial cell carcinoma and recorded tobacco history were included. Patients were stratified by tobacco history into nonsmokers, light smokers (≤30 pack-years), and heavy smokers (>30 pack-years). An additional analysis was performed looking at patients meeting National Lung Cancer Screening Trial (NLCST) criteria (55- to 74-year-old patients with ≥30 pack-years smoking history and Results We identified 197 (26.6%) nonsmokers, 251 (33.9%) light smokers, and 292 (39.5%) heavy smokers. Males were more likely to be heavy smokers (44.5% vs 23.6%, P ≤.01). Compared with nonsmokers and light smokers, the initial tumors in heavy smokers were more likely to be high grade with a more advanced clinical stage. Heavy smokers were more likely to present with muscle-invasive bladder cancer (MIBC) at initial diagnosis. When compared to nonsmokers, the odds ratio for presenting with MIBC was 1.18 (95% confidence interval = 0.68-2.1) for light smokers and 1.38 (95% confidence interval = 1.06-1.8) for heavy smokers. Of 793 patients with adequate information for analysis, 184 (23.2%) met NLCST criteria. Those meeting NLCST criteria were most likely to be male, to present with gross hematuria, and to have initial tumors that were high grade and muscle invasive. NLCST criteria eligibility remained associated with MIBC on multivariate analysis. Conclusion Heavy smokers and patients meeting NLCST criteria are more likely to have high-grade tumors with detrusor muscle invasion at initial presentation.
Chabrol for Beginners (and Other Interested Parties)

Guy Austin _Claude Chabrol_ Manchester and New York: Manchester University Press, 1999 ISBN 0 7190 5271 8 (hb); 0 7190 5272 6 (pb) 197 pp.
Microsomal metabolism of arylamides by the rat and guinea pig--I. Oxidation of N-3-fluorenylacetamide at carbon-atom-9--a major metabolic reaction.

Abstract The N-hydroxylation of N-3-fluorenylacetamide (3-FAA), an isomer of the carcinogen, N-2-fluorenylacetamide (2-FAA), by hepatic microsomes of untreated and 3-methylcholanthrene (3-MC)-treated guinea pigs was found to be of a similar low order as that previously observed in the rat. Hepatic microsomes of the guinea pig and of the rat converted 3-FAA to N-(9-hydroxy)-3-FAA and to N-(9-oxo)-3-FAA. These new metabolites were separated and identified by high-pressure liquid chromatography (h.p.l.c.). N-(9-hydroxy)-3-FAA was the major product of the hydroxylation of 3-FAA by hepatic microsomes of the rat or guinea pig exceeding the formation of N-(7-hydroxy)-3-FAA, the principal phenolic metabolite of 3-FAA. The amounts of N-(9-oxo)-3-FAA formed were about one-third of the amounts of N-(9-hydroxy)-3-FAA produced. In contrast to the formation of phenolic metabolites, the hydroxylation of 3-FAA to N-(9-hydroxy)-3-FAA was not increased by pretreatment of guinea pigs or rats with 3-MC. Similarly, pretreatment of rats with PB did not enhance the yield of N-(9-hydroxy)-3-FAA. Co inhibited the formation of N-(9-hydroxy)-3-FAA by 80 per cent. These data lead us to conclude that the formation of N-(9-hydroxy)-3-FAA is catalyzed by a microsomal hemoprotein not identical with cytochrome P1-450 or P-450. In contrast to 3-FAA, 2-FAA appeared to be a poor substrate for hydroxylation to the N-(9-hydroxy)-2-FAA. The susceptibility of 3-FAA to hydroxylation at carbon-atom 9 of the fluorene moiety may be rationalized by resonance structures in which carbon-atom 9 is positively charged and acts as a electrophilic center. Similar resonance structures cannot be written for 2-FAA.
Possible Role of Fungal Hemolysins in Sick Building Syndrome

Publisher Summary The chapter first reviews fungal hemolysins and compares them with bacterial hemolysins. Hemolysins are molecules that have the ability to lyse red blood cells (RBCs). There are primarily two types of hemolysins: alpha (α) and beta (β). Alpha hemolysins cause a partial lysis of the RBCs, resulting in a darkening of the media around a colony on sheep's blood agar (SBA). Beta hemolysins produce a complete lysis of the RBCs, resulting in a clearing around the colony growing on SBA. The chapter discusses the biochemistry of hemolysins. Hemolysins are produced by many of the common indoor fungi. Fungal hemolysins might be useful as biomarkers of exposure to indoor fungi because they can be measured in bodily fluids and environmental samples. Fungal hemolysins are generally composed of smaller-molecular-weight monomers than most bacterial hemolysins. They usually have more acidic isoelectric points and contain more cysteine amino acids than bacterial hemolysins. Fungal hemolysins are remarkably slow acting as compared with bacterial hemolysins. However, like most bacterial hemolysins, fungal hemolysins are aggregating proteins that create pores in membranes.
Instrumentation considerations in research involving eye-movement contingent stimulus control

In the study of perception during reading the use of eye movement contingent control of the stimulus display has proved to be a useful research technique. With such a system it is possible to experimentally manipulate, in real time, the characteristics of the stimulus display that is present on selected fixations as reading is in progress, and to observe the effects of the manipulation on the eye movement pattern. This technique can also be used in the study of other on-going, visually based tasks. This paper provides examples of how the technique has been used, and describes a number of the instrumentation concerns which are important to consider when setting up a system to do this type of research.
A Study of the Multiplicity of Lysine-rich Histones

Fractions of lysine-rich histones have been obtained from rabbit thymus and mammary gland by chromatography on Amberlite IRC-50 with shallow guanidinium chloride gradients. The peaks obtained were rechromatographed using still shallower gradients. Only one of nine peaks was found to be significantly inhomogeneous on rechromatography. Furthermore, each of the other eight peaks was as narrow as a chromatographically homogeneous sample and each was electrophoretically homogeneous on polyacrylamide gel. All fractions from the thymus possessed blocked aminoterminal residues and were terminated at the carboxyl end by 2 adjacent lysine residues. It was concluded that this system of chromatography had been extended nearly to its limit of resolving power and that the complexity of these chromatographic patterns approximates the true multiplicity of lysine-rich histones.
Howard Receives 2013 G. K. Gilbert Award: Citation

Alan Howard is the recipient of the 2013 Earth and Planetary Surface Processes focus group's G. K. Gilbert Award.
Terrible Lizards--Impure Science?

The Last Dinosaur Book The Life and Times of a Cultural Icon. W. J. T. Mitchell. University of Chicago Press, Chicago, 1998. 333 pp. $35. ISBN 0-226-53204-6. This is not another book about dinosaurs, but an examination of dinosaurs in popular culture, past and present. Mitchell9s enthusiastic, though sometimes superficial, study touches on dinosaur appearances in settings ranging from books to business, movies to museums, and television to toy stores.
A Meta‐Analysis of Imitation Abilities in Individuals With Autism Spectrum Disorders

Although imitation impairments are often reported in individuals with autism spectrum disorders (ASD), previous work has not yet determined whether these impairments are significant, specific to ASD, and present across the entire spectrum. This report of 53 studies on imitation in ASD seeks to determine whether individuals with ASD show significant imitation deficits, the magnitude of these deficits, and whether they are specific to ASD. Using standard meta-analytic techniques in a random-effects model, the data reviewed suggest that individuals with ASD show deficits in imitation, performing on average 0.81 SDs below individuals without ASD on imitation tasks. This deficit was specific to the condition of having ASD. Moderator analyses revealed that the average Autism Diagnostic Observation Schedule (ADOS) scores of groups of ASD participants were significantly and strongly negatively associated with the imitation abilities of these subjects, but average participant IQ was not associated with imitation abilities. Study setting, novelty of actions, format of imitation tasks (live vs. not), number of actions to imitate, or verbal prompts were not found to significantly affect the sizes of the imitation differences between individuals with and without ASD. The manner in which imitation was operationalized, however, had significant effects on whether imitation deficits were found between individuals with and without ASD. In tests that measured imitation of both form and end points, participants with ASD showed significant deficits compared with those without ASD; on tests of end point emulation only, individuals with ASD showed no deficits. Autism Res 2014, 7: 363–380. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.
Systemic mastocytosis in adults: 2013 update on diagnosis, risk stratification, and management

Disease overview Systemic mastocytosis (SM) results from a clonal proliferation of abnormal mast cells (MC) in one or more extracutaneous organs. Diagnosis The major criterion is presence of multifocal clusters of morphologically abnormal MC in the bone marrow. Minor diagnostic criteria include elevated serum tryptase level, abnormal MC expression of CD25 and/or CD2, and presence of KITD816V. Risk stratification The 2008 World Health Organization (WHO) classification of SM has been shown to be prognostically relevant. Classification of SM patients into indolent (SM), aggressive SM (ASM), SM associated with a clonal non-MC lineage disease (SM-AHNMD) and mast cell leukemia (MCL) subgroups is a useful first step in establishing prognosis. Management SM treatment is generally palliative. ISM patients have a normal life expectancy and receive symptom-directed therapy; infrequently, cytoreductive therapy may be indicated for refractory symptoms. ASM patients have disease-related organ dysfunction; interferon-α (±corticosteroids) can control dermatological, hematological, gastrointestinal, skeletal, and mediator-release symptoms, but is hampered by poor tolerability. Similarly, cladribine has broad therapeutic activity, with particular utility when rapid MC debulking is indicated; the main toxicity is myelosuppression. Imatinib has a therapeutic role in the presence of an imatinib-sensitive KIT mutation or in KITD816-unmutated patients. Treatment of SM-AHNMD is governed primarily by the non-MC neoplasm; hydroxyurea has modest utility in this setting. Investigational drugs Dasatinib's in vitro anti- KITD816V activity has not translated into significant therapeutic activity in most SM patients. In contrast, recently updated data confirms Midostaurin's significant anti-MC activity in patients with advanced SM.
A Balancing Act: Work–Life Balance and Multiple Stakeholder Outcomes in Hospitals

This article examines the direct and indirect effects of work–life balance (WLB) practices on multiple stakeholder outcomes in hospitals. The authors examine the direct and indirect effects of WLB practices in 173 hospitals in the United Kingdom on organizational, patient care and employee outcomes. The article proposes a model in which the effects of WLB practices on patient care outcomes and financial performance are mediated by employee turnover intentions. The authors provide strong support for the potential vested in WLB practices in the healthcare setting. Results indicate that greater use of WLB practices enhances outcomes for hospitals, their employees and the patients they care for.
Showing Up, Remaining Engaged, and Partaking as Students: Resilience Among Students of Mexican Descent

This paper examines the ways in which 12 high school students of Mexican descent remain resilient amid difficult and stressful realities. Through an examination of students' interview responses, a case is made that students' ability to engage in school and figure out everyday ways to partake as students are signs of resilience. This work suggests the need to shift from a focus on single, specific stressful situations or experiences to a more accurate and less essentialized understanding of both constraints and capabilities around student engagement and well-being.
BioMEMS: Forging New Collaborations Between Biologists and Engineers

This video describes the fabrication and use of a microfluidic device to culture central nervous system (CNS) neurons. This device is compatible with live-cell optical microscopy (DIC and phase contrast), as well as confocal and two photon microscopy approaches. This method uses precision-molded polymer parts to create miniature multi-compartment cell culture with fluidic isolation. The compartments are made of tiny channels with dimensions that are large enough to culture neurons in well-controlled fluidic microenvironments. Neurons can be cultured for 2-3 weeks within the device, after which they can be fixed and stained for immunocytochemistry. Axonal and somal compartments can be maintained fluidically isolated from each other by using a small hydrostatic pressure difference; this feature can be used to localize soluble insults to one compartment for up to 20 h after each medium change. Fluidic isolation enables collection of pure axonal fraction and biochemical analysis by PCR. The microfluidic device provides a highly adaptable platform for neuroscience research and may find applications in modeling CNS injury and neurodegeneration.
The Appell transform and the semigroup property for temperatures

We prove that if u(x, t) is a solution of the one dimensional heat equation and if A u(x, t) is its Appell transform, then u(x, t) has the semi-group (Huygens) property in a domain D if and only if A u(x, t) has the semi-group property in a dual region. We apply this result to simplify and extend some results of Rosenbloom and Widder.
Status and Prospects of the NOνA Experiment

NOνA is a proposed experiment to search for ν μ → ν e oscillations using the NuMI neutrino beam, and two detectors separated by a baseline of 810 km. A better signal-to-background ratio than that of current experiments will be achieved by using detectors with a low Z/A ratio, and by situating the far detector off the beam axis. NOνA will have sensitivity to the related physics of the neutrino mass hierarchy and leptonic CP violation depending on the values of the mixing angle θ 13 and the CP violation angle δ.
Reserpine increases Fos activity in the rat basal ganglia via a quinpirole-sensitive mechanism.

Abstract Expression of the immediate early gene c- fos increases acutely following neuronal depolarization, c- fos and Fos protein have been widely used to investigate basal ganglia responses to changes in dopaminergic neurotransmission. Increased dopaminergic input to D1 receptors increases Fos synthesis in striatal neurons. The role of D2 receptors in regulating Fos activity has been more difficult to establish. Because dopamine is believed to excite striatal neurons via D1 receptors and inhibit them via D2 receptors, we hypothesized that acute dopamine depletion would increase Fos activity in basal ganglia circuits normally inhibited by dopaminergic input to D2 receptors. Rats were perfused after a single dose of the dopamine-depleting drug reserpine. The brains of rats perfused 3 h after reserpine displayed numerous Fos-like immunoreactive nuclei in the striatum, entopeduncular nucleus, nucleus accumbens shell, and ventral pallidum, and sparse Fos-like immunoreactive nuclei in the globus pallidus and nucleus accumbens core. Few or no Fos-like immunoreactive nuclei were seen following perfusion 30 min, 60 min, and 24 h after reserpine. In the 3-h paradigm, pretreatment with the selective D1 antagonist SCH 23390 did not change the pattern of Fos-like immunoreactivity; pretreatment with the selective D2 agonist quinpirole completely blocked increased Fos synthesis. Acute dopamine depletion, therefore, increases Fos activity in the basal ganglia by disinhibiting D2 circuits. These results support the parallel pathway model of basal ganglia function, and show that Fos can be used to investigate the role of D2 receptors in striatal function. The findings suggest anatomic correlates for the clinical effects of acute dopamine depletion in drug therapy and advanced Parkinson's disease in humans.
The Coast Guard's Differential GPS Programme

The US Coast Guard has a project to provide a differential global positioning system service for harbour and harbour approach (HHA) areas of the coastal United States. The Great Lakes, Puerto Rico and most of Alaska and Hawaii will also be covered by the service. The Coast Guard's DGPS system will fulfil the 8–20 metre navigation accuracy requirement for HHA with an availability of up to 999 percent. The Coast Guard intends to provide this service to the general public and other government agencies, as well as use the system for its own missions. This capability is expected to enhance maritime safety in keeping with the National Transportation Policy by providing an all-weather radionavigation service to supplement existing radar and visual techniques, as well as a highly accurate position sensor for future electronic chart displays. This paper describes the Coast Guard's programme. Background and historical information on the development of pseudorange differential GPS is presented first, followed by a description of currently available technology. Various aspects of the Coast Guard's plan for implementing DGPS are then described, concluding with a rough project time line and a statement concerning Federal DGPS policy.
Thermally metamorphosed carbonaceous chondrites from data for thermally mobile trace elements

— We report radiochemical neutron activation analysis (RNAA) data for U, Co, Au, Sb, Ga, Rb, Cs, Se, Ag, Te, Zn, In, Bi, Tl, and Cd (ordered by increasing ease of vaporization and loss from the Murchison CM2 chondrite during open-system heating) in nine Antarctic C2 and C3 chondrites. These meteorites exhibit properties (obtained by reflectance spectroscopy, O isotopic mass spectrometry and/or mineralogy-petrology) suggesting thermal metamorphism in their parent bodies. Five of these meteorites (Asuka (A) 881655, Yamato (Y) 793495, Y-790992, Pecora Escarpment (PCA) 91008, and Y-86789—paired with Y-86720) exhibit significant depletion of the most thermally mobile 1–5 trace elements, which is consistent with open-system loss during extended parent-body heating (under conditions duplicated by week-long heating of the Murchison C2 chondrite, heated at 500–700 °C in a low-pressure (initially 10−5atm) H2 atmosphere). From earlier data, three other C3 chondrites—Allan Hills (ALH) 81003, ALH 85003, and Lewis Cliffs (LEW) 85332—show significant Cd depletion. Nine additional C2 and C3 chondrites show no evidence of mobile trace element depletion—including Y-793321, which by all other criteria was mildly metamorphosed thermally. Either metamorphism of these nine meteorites occurred under closed conditions and/or alteration took place under such mild conditions that even Cd could not be lost. The RNAA data suggest that 10 of the 46 Antarctic carbonaceous chondrites (including 4 of 37 from Victoria Land and 6 of 9 from Queen Maud Land) exhibit open-system loss of at least some thermally mobile trace elements by heating in their parent bodies, whereas none of the 25 non-Antarctic falls experienced this. These results are consistent with the idea that the Antarctic sampling of near-Earth material differs from that being sampled today.
1497 URINARY BETA-2-MICROGLOBULIN (β 2 M) AS AN INDEX OF RENAL TUBLAR MATURATION IN HUMAN NEONATES

Tubular reabsorption of β2M was previously reported to increase with conceptional age (CA) and to reflect maturation of renal tubular function. To study this concept further, timed-urine collections and blood samples were obtained on 50 newborn infants (CA 28-42 wks) between 1-12 days of age. Creatinine, sodium and β2M were measured in urine and plasma; creatinine clearance (CCR) and fractional reabsorption of sodium (TNa) and β2M (Tβ2M) were calculated. Plasma β2M concentrations (3.63 ± 0.14 mg/liter, mean ± SE) did not vary with CA (r=0.085). CCR (r=0.715), TNa (r=0.627) and Tβ2M (r=0.693) increased with CA of the infants (p<0.001). Moreover, Tβ2M varied directly with TNa (r=0.474, p<0.001) and inversely with fractional urine flow rate (V/CCR) (r= -0.601, p<0.001). In serial studies of 18 infants 3.64 ± 0.67 (range 1-12) days later, changes in Tβ2M in the same infant were observed to vary inversely with changes in V/CCR (r= -0.470, p=0.05). Although the results of this study confirm previous reports that Tβ2M increases with CA of the infant, these data do not support Tβ2M as a reliable index of renal tubular maturation in the human neonate.
International Elections on US Network News: An Examination of Factors Affecting Newsworthiness

A content analysis examined factors that could predict coverage of international elections on US newscasts. All 138 elections held between 1 January 1998 and 1 May 2000 were included in the analysis. Many of the results run counter to previous findings. Countries with few ancestral ties with the US, with nuclear arms or developing nuclear arms, with close relations with China, with low trade with the US and in regions with conflicts were more likely to receive election coverage than other nations. In general, while the elections offer the news media the opportunity to show positive news — democracy in action — coverage continues to concentrate on the negative by highlighting elections in those countries that pose potential threats and are relatively unknown to the US.
The Effect of Beta-Aminopropionitrile on the Blood Pressure of Turkeys

Abstract SCHILLING and Strong (1955) characterized the toxic principle found in sweet pea seeds (Lathyrus odoratus), which produced lathyrism in rats, as beta (N-gamma-L-glutamyl) aminopropionitrile. Barnett et al. (1957) likened the natural occurring condition of dissecting aneurysms (aortic rupture) in turkeys to the dissecting aneurysms observed in rats following the artificial induction of lathyrism by B-aminoproprionitrile (BAPN) feeding. These later workers demonstrated that levels of 0.0313 and 0.04 percent BAPN incorporated into the feed of day-old poults resulted in death as a result of aortic rupture in 15 percent and 33 percent of the poults prior to 28 days of age. Ringer and Rood (1959) reported that the Broad Breasted Bronze turkey has an extremely high normal blood pressure level and suggested that the hypertension may contribute to field cases of aortic rupture in turkeys. Ringer (1959) postulated that the lowering of blood pressure in the turkey by the use of…
Interface structure in arsenide/phosphide heterostructures grown by gas-source MBE and low-pressure MOVPE

We have used cross-sectional scanning tunneling microscopy (STM) to study interface structure in arsenide/phosphide heterostructures grown by gas-source molecular beam epitaxy (GSMBE) and by low-pressure metalorganic vapor phase epitaxy (LP-MOVPE). High-resolution images of GSMBE samples consisting of GaAs interrupted at 200A intervals with a 40 s P2 flux reveal substantial, growth-temperature-dependent incorporation of phosphorus with nanometer-scale lateral variations in interface structure. STM images of InGaAs/InP multiple quantum well structures grown by LP-MOVPE show evidence of interface asymmetry and extensive atomic cross-incorporation at the interfaces. Data obtained by STM have been corroborated by high-resolution x-ray diffraction and reflection high-energy electron diffraction. Together, these studies provide direct information about nanometer-scale grading and lateral nonuniformity of arsenide/phosphide interfaces that can occur under these growth conditions.
High-level expression from a cytomegalovirus promoter in macrophage cells

ABSTRACT To identify vectors that provide optimal gene expression in human hematopoietic cells, we investigated retroviruses containing the adenosine deaminase (ADA) gene under the transcriptional control of the promoters/enhancers of Moloney murine leukemia virus and the human cytomegalovirus (CMV) immediate-early gene. ADA expression was monitored in transduced human multipotential promyelocytic leukemic HL-60 cells and human monocytic leukemic THP-1 cells. HL-60 cells can be induced by phorbol ester to differentiate into macrophage lineage cells and by retinoic acid into granulocytic cells. THP-1 cells undergo phorbol ester-induced differentiation to macrophage cells. In LNCA-transduced HL-60 derived macrophage cells, ADA controlled by the CMV promoter was expressed at 100.0 μmol/hr·mg, in contrast to 1.2 μmol/hr·mg from LN-transduced control cells. LNCA-transduced THP-1 macrophage cells showed a similar increase in ADA activity over control cells. These elevated enzyme activities were confirmed by Nor...
TG-21 versus TG-25: A comparison for electrons

Since 1984, the Radiological Physics Center (RPC) has used the American Association of Physicists in Medicine Task Group 21 (TG-21) protocol (absorbed dose determination) as the basis of its On-site Dosimetry Review visits to institutions participating in the National Cancer Institute's cooperative clinical trials. Subsequent to the TG-21 protocol, the Task Group 25 (TG-25) report on electron-beam dosimetry was published. The TG-25 report was not intended to supercede the TG-21 protocol, but to supplement it for depths other than dmax. However, both reports included measurement techniques and data regarding the calibration of electron beams. TG-25 was not intended for absolute calibrations made clear by the fact that it does not present all of the data required for plastic phantom calibrations, i.e., unrestricted stopping power ratios. As a result, some confusion has arisen at various institutions as to which protocol should be used for machine calibration. In this study, possible discrepancies that arise when using TG-21, a version of TG-21 modified by the RPC, and TG-25 are compared. The differences in the results are calculated as a function of energy (6 and 20 MeV), chamber type (cylindrical or parallel plate), and the type of phantom material (water, polystyrene, or acrylic). The largest discrepancies noted were between TG-25 and the two TG-21 methods for low-energy electrons in either water or polystyrene. The mean difference for all conditions was 0.8% with a maximum value of 3.3% in polystyrene. The definition of the effective point of measurement; determination of the mean nominal incident energy (E0), mean energy at depth (EZ) and most probable energy at the surface (Ep,0) for each protocol, and subsequent stopping power ratio, chamber replacement factor, and electron fluence correction factor are the major contributors to the calculated differences.
Measurement of low velocity and quasi-static failure modes in PMMA

An investigation of the low velocity impact and quasi-static failure of polymethylmethacrylate (PMMA) based on global and local strain measurements was conducted. Local strains were obtained from surface-mounted fiber Bragg grating (FBG) sensors, and they were combined with global measurements from quasi-static indentation and low-velocity impact experiments to obtain detailed maps of how failure evolves. For both loading regimes, the interactions between the host PMMA specimens and the sensors played a crucial role in the evolution of residual strains. A mapping of the strains clearly shows that strains decrease radially, from high values near the point of impact to far-field values. Sensors located in critical locations had the highest residual strains prior to PMMA fracture. Furthermore, it was determined that strain transfer to the sensor is strongly influenced by the bonding conditions at the specimen's surface. Because of the debonding of the sensor and the frictional effects associated with the bonding agent, compressive residual strains occurred on the rear-surface. Hence, a detailed understanding of how strain evolves due to sensor–host interactions and catastrophic fracture can be obtained, which can potentially be used to mitigate damage in PMMA for a range of strain rates. POLYM. COMPOS., 28:381–391, 2007. © 2007 Society of Plastics Engineers
The dimer formed by the periplasmic domain of EpsL from the Type 2 Secretion System of Vibrio parahaemolyticus.

Abstract The Type 2 Secretion System (T2SS), occurring in many Gram-negative bacteria, is responsible for the transport of a diversity of proteins from the periplasm across the outer membrane into the extracellular space. In Vibrio cholerae , the T2SS secretes several unrelated proteins including the major virulence factor cholera toxin. The T2SS consists of three sub-assemblies, one of which is the Inner Membrane Complex which contains multiple copies of five proteins, including the bitopic membrane protein EpsL. Here, we report the 2.3 A resolution crystal structure of the periplasmic domain of EpsL (peri-EpsL) from Vibrio parahaemolyticus , which is 56% identical in sequence to its homolog in V. cholerae . The domain adopts a circular permutation of the “common” ferredoxin fold with two contiguous sub-domains. Remarkably, this infrequently occurring permutation was for the first time observed in the periplasmic domain of EpsM (peri-EpsM), another T2SS protein which interacts with EpsL. These two domains are 18% identical in sequence which may indicate a common evolutionary origin. Both peri-EpsL and peri-EpsM form dimers, but the organization of the subunits in these dimers appears to be entirely different. We have previously shown that the cytoplasmic domain of EpsL is also dimeric and forms a heterotetramer with the first domain of the “secretion ATPase” EpsE. The latter enzyme is most likely hexameric. The possible consequences of the combination of the different symmetries of EpsE and EpsL for the architecture of the T2SS are discussed.
APFIM characterization of a high phosphorus Russian RPV weld

Abstract A microstructural characterization of a high phosphorus (0.035 wt% P) weld from the pressure vessel of a Russian VVER nuclear reactor has been performed. The microstructure of these steels consists of intragranular and intergranular vanadium carbonitride precipitates of average composition 51.3 ± 0.9 at% V, 18.8 ± 0.7 at% C, 22.1 ± 0.7 at% N, 4.9 ± 0.4 at% Cr, 2.4 ± 0.3 at% Mo, 0.36 ± 0.05 at% Fe, 0.07 ± 0.05 at% B and 0.03 ± 0.03 at% P. The lath and grain boundaries were also coated with a thin film of molybdenum carbonitride precipitates. The phosphorus coverage at the boundaries in the unirradiated material was ∼ 13% of a monolayer in agreement with predictions from the McLean model of equilibrium segregation. After neutron irradiation to a fluence of 1.15 × 10 20 n cm −2 , the phosphorus coverage had increased significantly to up to ∼ 60% of a monolayer. This result indicates that neutron irradiation significantly enhanced the phosphorus segregation process. Phosphorus and copper clusters were also observed in the matrix of the neutron-irradiated material.
Induction of tyrosine hydroxylase by forskolin: modulation with age

Abstract With aging, circulating catecholamines are elevated in both humans and animals. This may be related to the increased basal levels of tyrosine hydroxylase messenger RNA (mRNA) levels and tyrosine hydroxylase enzyme activity in the adrenal medulla of senescent compared with younger animals. In addition, tyrosine hydroxylase gene expression in the senescent rat is resistant to further stimulation by cold exposure as compared with younger animals. Collectively, these observations suggest either that tyrosine hydroxylase expression is already maximally stimulated in senescent rats or that tyrosine hydroxylase gene induction pathways are impaired with senescence. To help distinguish between these possibilities, we examined the induction of tyrosine hydroxylase mRNA, tyrosine hydroxylase immunoreactivity and tyrosine hydroxylase enzyme activity in the adrenal medulla following forskolin administration to young and old F-344 rats. Forskolin at doses of 1.8 and 3.5 mg/kg increased tyrosine hydroxylase mRNA levels 2.5-fold in adrenal medulla from young rats but did not increase either tyrosine hydroxylase immunoreactivity or tyrosine hydroxylase enzyme activity 5 h after administration. Prolonged treatment with forskolin (3 doses, 12 h apart) increased tyrosine hydroxylase mRNA levels and tyrosine hydroxylase immunoreactivity and tyrosine hydroxylase enzyme activity. In senescent rats, the baseline level of tyrosine hydroxylase mRNA was more than 2-fold higher compared with young rats. A single injection of the lower dose of forskolin increased tyrosine hydroxylase mRNA levels by the same increment in senescent as compared with young rats. These data indicate that the tyrosine hydroxylase gene in the adrenal medulla from senescent rats is still capable of further stimulation. © 1997 Elsevier Science B.V. All rights reserved.
O2-promoted allylic acetoxylation of alkenes: Assessment of “push” versus “pull” mechanisms and comparison between O2 and benzoquinone

Abstract Palladium-catalyzed acetoxylation of allylic C–H bonds has been the subject of extensive study. These reactions proceed via allyl-palladium(II) intermediates that react with acetate to afford the allyl acetate product. Benzoquinone and molecular oxygen are two common oxidants for these reactions. Benzoquinone has been shown to promote allyl acetate formation from well-defined π-allyl palladium(II) complexes. Here, we assess the ability of O2 to promote similar reactions with a series of “unligated” π-allyl palladium(II) complexes (i.e., in the absence of ancillary phosphorus, nitrogen or related donor ligands). Stoichiometric and catalytic allyl acetate formation is observed under aerobic conditions with several different alkenes. Mechanistic studies are most consistent with a “pull” mechanism in which O2 traps the Pd0 intermediate following reversible C–O bond formation from an allyl-palladium(II) species. A “push” mechanism, involving oxidatively induced C–O bond formation, does not appear to participate. These results and conclusions are compared with benzoquinone-promoted allylic acetoxylation, in which a “push” mechanism seems to be operative.
Problems, methods, and achievements in conforming to standards for vehicular radio frequency interference

Increased usage of the Land Mobile Service, increasing sensitivity of receivers, and greater demands on communication systems are causing attention to be directed toward interference radiated from automotive ignition systems. Although U.S. vehicles are presently designed to limit radiation, lack of uniformity exists between standards in North America and Europe resulting in duplication of test work. The United States automotive industry is cooperating in the development of a world-wide standard using a unique sampling procedure, and has used new computer techniques to derive a greater amount of information from data available. Revisions now under way in the U.S. industry Standard will provide procedures and limits to 1000 MHz, will protect all present TV bands, and will make our standards compatible with Common Market usage. Theoretical studies and testing show that vehicular radiation decreases above 400 MHz and that existing techniques may prove satisfactory. Joint studies of an FCC-industry group are expected to develop additional information.
Solution NMR Studies and Crystal Structure of the Water-Soluble Iron(III) Porphyrin Iron 5,10,15,20-Tetrakis(2,3,5,6-tetrafluoro-4-N,N,N-trimethylaniliniumyl)porphyrin ([FeTF4TMAP]5+)

The crystal structure of [FeIII(TF4TMAP)(H2O)2](CF3SO3)5·2CH3CN·2H2O (a = 13.065(2) A, b = 13.375(2) A, c = 13.839(2) A, α = 110.97°, β = 104.97°, γ = 94.22°, V = 2144.2(6) A3, Z = 1) shows that th...
Epitaxial Growth of ZrO2 on GaN by MOMBE for High Dielectric Material Applications

Epitaxial growth of ZrO 2 has been achieved on MOCVD grown GaN template by oxides MBE using a reactive H 2 O 2 oxygen source. Using the low temperature buffer followed by high temperature in-situ annealing and high-temperature growth, monoclinic, (100)-oriented ZrO 2 thin film with decent structural quality and smooth surface morphology was achieved. The full width at half maximum of ZrO 2 (100) rocking curve is 0.4 arc degree and the rms roughness for a 5μm by 5 μm AFM scan is 4.1A. The use of epitaxially grown ZrO 2 in the AlGaN/GaN HFET structure as a gate dielectric layer have resulted in the increase of the saturation-current density and pinch-off voltage as well as showed near symmetrical gate-drain I-V behavior.
Risk and risk factors for blindness from glaucoma.

Purpose of review Estimates of blindness from glaucoma and risk factors for blindness remain of interest for all ophthalmologists. Recent findings Long-term retrospective studies of patients with open-angle glaucoma in developed countries have noted that progression to bilateral blindness among treated patients is relatively uncommon. Risk factors for development of blindness include advanced visual field loss at presentation and noncompliance with the treatment regimen. Age is a risk factor in some studies. Many of those with blindness are blind at presentation. Untreated rates of blindness are higher. Population-based studies of glaucoma in developing countries have highlighted the obstacles to prevention of blindness in such settings, with astonishingly high rates of blindness noted. Summary The risk of blindness from glaucoma is very high among patients in developing countries, the vast majority of whom do not know they are afflicted. When considering all glaucoma worldwide, the greatest risk factor for blindness is almost certainly being an average citizen of a developing country. Among those with open-angle glaucoma in developed countries, more advanced visual field loss at presentation and noncompliance are risk factors for development of blindness, as well as advanced age. Effective public education about glaucoma and targeted screening of those most likely to have glaucoma are necessary if the number of blind from glaucoma is to be reduced worldwide. Better treatment options for those in developing countries must also be developed.
Is It Love or The Lobby? Explaining America's Special Relationship with Israel

In The Israel Lobby and U.S. Foreign Policy, we argued that the “special relationship” between the United States and Israel is due largely to the influence of a domestic interest group—comprised of Jews as well as non-Jews—and that this unusual situation is harmful to both the United States and Israel. Jerome Slater's thoughtful review endorses many of our central arguments, but it also highlights several points of disagreement. He argues that we overlooked important alternative sources, defined the lobby too broadly, and exaggerated its influence on Congress and especially the Executive Branch. Although Slater is even more critical of U.S. Middle East policy than we are, he argues that the special relationship is due to strong cultural and religious affinities and broad public support in American society, and not to the influence of the lobby. In fact, the alternative sources cited by Slater do not undermine our basic claims; a broad conception of the lobby makes more sense than his narrower definition; ...
Apical myectomy: A new surgical technique for management of severely symptomatic patients with apical hypertrophic cardiomyopathy

Objective Apical hypertrophic cardiomyopathy is a morphologic variant in which the hypertrophy is primarily localized to the apex of the left ventricle. A subset of patients have progressive, drug-refractory diastolic heart failure with severely limiting symptoms caused by low cardiac output. Heart transplantation has been the only therapeutic option available for such patients. This study analyzes clinical and hemodynamic outcomes of a novel surgical technique to improve diastolic filling by means of left ventricular cavity enlargement. Methods Forty-four symptomatic patients underwent apical myectomy to augment left ventricular end-diastolic volume. Myectomy was performed through an apical incision, and hypertrophic muscle was excised at the apex and midventricle. Information from a prospective database was supplemented by surveys, patient contact, and medical records. Results The mean age of the patients was 50 ± 17 years, and 66% were women. All patients were severely limited with dyspnea, 61% had angina, and 59% had syncope/presyncope. Ninety-one percent of patients were in New York Heart Association class III or IV. A mean of 16 ± 7 g of muscle was removed. Preoperative and postoperative hemodynamic catheterization (n = 14) showed a decrease in left ventricular end-diastolic pressure from 28 ± 9 to 24 ± 7 mm Hg ( P = .002) and an increase in end-diastolic volume index from 55 ± 17 to 68 ± 18 mL/m 2 ( P = .003). Invasive measurements of stroke volume increased from 56 ± 17 to 63 ± 19 mL ( P = .007). Of the 42 patients who survived to hospital discharge, 41 had improvement in symptoms. Mean peak maximum oxygen consumption with exercise (n = 5) increased from 13.5 ± 4.4 to 15.8 ± 4.6 mL/kg per minute. Survival at 1, 3, and 5 years was 95%, 81%, and 81%, respectively. At follow-up of 2.6 ± 3.1 years, 23 (74%) patients were in New York Heart Association class I or II. One patient underwent heart transplantation 5 years after apical myectomy. Conclusions Apical myectomy improves functional status by decreasing left ventricular end-diastolic pressure, improving operative compliance, and increasing stroke volume. This procedure might be of value in other patients with hypertrophic cardiomyopathy who have severe hypertrophy and small left ventricular end-diastolic volume.
Microcanonical simulation of the three-dimensional random-field Ising model.

Results of large microcanonical simulations of the three-dimensional random-field Ising model are reported, including the distribution of local magnetizations. Domains are shown to be formed already above ${T}_{c}$. The apparent behavior near the critical point, strongly affected by divergent relaxation times, varies with the random-field excess. For some realizations the sudden flip of a large domain appears as a discontinuous transition.
Interferon‐γ, tumor necrosis factor‐α, and transforming growth factor‐β inhibit cyclic AMP‐induced Schwann cell differentiation

Schwann cells differentiate in vivo in response to contact with axons, and cAMP simulates some of these aspects of differentiation in vitro, particularly morphologic changes and expression of certain phenotypic molecules. Unfractionated inflammatory cytokines inhibit cAMP-induced Schwann cell expression of galactolipids (Gal). We sought to identify which cytokines were responsible for this inhibition and to determine whether other phenotypic indicators of Schwann cell differentiation were also affected. Neonatal rat Schwann cells were incubated in vitro with 1 mM 8 Bromo cAMP (8 Br cAMP) with or without the addition of interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-2, IL-6, tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), or transforming growth factor-beta (TGF-beta). Cells were then examined for morphologic changes and for expression of surface Gal and low-affinity nerve growth factor receptor (NGFRp75), employing indirect immunofluorescence. 8 Br cAMP induced Schwann cell upregulation of Gal, downregulation of NGFRp75, and the cells became enlarged and somewhat amorphous and irregular in appearance. Cells treated with IFN-gamma or TNF-alpha alone were more bipolar and more evenly distributed on coverslips than were control cells, whereas TGF-beta alone induced elongated cells often in a swirling pattern. None of the cytokines alone induced upregulation of Gal or downregulation of NGFRp75. TNF-alpha, IFN-gamma, and TGF-beta inhibited the 8 Br cAMP-induced morphologic changes, as well as the upregulation of Gal and downregulation of NGFRp75. The other cytokines had no effects on Gal or NGFRp75 expression. Thus, these three cytokines, which are present in inflammatory lesions in the peripheral nervous system, are capable of inhibiting Schwann cell differentiation.
Modeling and Design of Building-Integrated Thermoelectrics

The goal of this research is to develop a framework for replacing conventional heating and cooling systems with distributed, continuously and electrically controlled, building-integrated thermoelectric (BITE) heat pumps. The coefficient of performance of thermoelectric heat pumps increases as the temperature difference across them decreases and as the amplitude of temperature oscillations decreases. As a result, this research examines how thermal insulation and mass elements can be integrated with thermoelectrics as part of active multi-layer structures in order to minimize net energy consumption. In order to develop BITE systems, an explicit finite volume model was developed to model the dynamic thermal response of active multi-layer wall structures subjected to arbitrary boundary conditions (interior and exterior temperatures and interior heat loads) and control algorithms. Using this numerical model, the effects of wall construction on net system performance were examined. These simulation results provide direction for the ongoing development of BITE systems.Copyright © 2011 by ASME