bluuebunny/crossref_metadata_2025 huggingface dataset:
Live imaging of the Drosophila spermatogonial stem cell niche reveals novel mechanisms regulating germline stem cell output
Authors: Sheng X. Rebecca , Matunis Erika
Published: July 2011

Adult stem cells modulate their output by varying between symmetric and asymmetric divisions, but have rarely been observed in living intact tissues. Germline stem cells (GSCs) in the Drosophila testis are anchored to somatic hub cells and were thought to exclusively undergo oriented asymmetric divisions, producing one stem cell that remains hub-anchored and one daughter cell displaced out of the stem cell-maintaining micro-environment (niche). We developed extended live imaging of the Drosophila testis niche, allowing us to track individual germline cells. Surprisingly, new wild-type GSCs are generated in the niche during steady-state tissue maintenance by a previously undetected event we term `symmetric renewal', where interconnected GSC-daughter cell pairs swivel such that both cells contact the hub. We also captured GSCs undergoing direct differentiation by detaching from the hub. Following starvation-induced GSC loss, GSC numbers are restored by symmetric renewals. Furthermore, upon more severe (genetically induced) GSC loss, both symmetric renewal and de-differentiation (where interconnected spermatogonia fragment into pairs while moving towards then establishing contact with the hub) occur simultaneously to replenish the GSC pool. Thus, stereotypically oriented stem cell divisions are not always correlated with an asymmetric outcome in cell fate, and changes in stem cell output are governed by altered signals in response to tissue requirements.
Concerted involvement of Cdx/Hox genes and Wnt signaling in morphogenesis of the caudal neural tube and cloacal derivatives from the posterior growth zone
Authors: van de Ven Cesca , Bialecka Monika , Neijts Roel , Young Teddy , Rowland Jennifer E. , Stringer Emma J. , Van Rooijen Carina , Meijlink Frits , Nóvoa Ana , Freund Jean-Noel , Mallo Moises , Beck Felix , Deschamps Jacqueline
Published: July 2011

Decrease in Cdx dosage in an allelic series of mouse Cdx mutants leads to progressively more severe posterior vertebral defects. These defects are corrected by posterior gain of function of the Wnt effector Lef1. Precocious expression of Hox paralogous 13 genes also induces vertebral axis truncation by antagonizing Cdx function. We report here that the phenotypic similarity also applies to patterning of the caudal neural tube and uro-rectal tracts in Cdx and Wnt3a mutants, and in embryos precociously expressing Hox13 genes. Cdx2 inactivation after placentation leads to posterior defects, including incomplete uro-rectal septation. Compound mutants carrying one active Cdx2 allele in the Cdx4-null background (Cdx2/4), transgenic embryos precociously expressing Hox13 genes and a novel Wnt3a hypomorph mutant all manifest a comparable phenotype with similar uro-rectal defects. Phenotype and transcriptome analysis in early Cdx mutants, genetic rescue experiments and gene expression studies lead us to propose that Cdx transcription factors act via Wnt signaling during the laying down of uro-rectal mesoderm, and that they are operative in an early phase of these events, at the site of tissue progenitors in the posterior growth zone of the embryo. Cdx and Wnt mutations and premature Hox13 expression also cause similar neural dysmorphology, including ectopic neural structures that sometimes lead to neural tube splitting at caudal axial levels. These findings involve the Cdx genes, canonical Wnt signaling and the temporal control of posterior Hox gene expression in posterior morphogenesis in the different embryonic germ layers. They shed a new light on the etiology of the caudal dysplasia or caudal regression range of human congenital defects.
Correlating SHAPE signatures with three-dimensional RNA structures
Authors: Bindewald Eckart , Wendeler Michaela , Legiewicz Michal , Bona Marion K. , Wang Yi , Pritt Mark J. , Le Grice Stuart F.J. , Shapiro Bruce A.
Published: July 2011

Selective 2′-hydroxyl acylation analyzed by primer extension (SHAPE) is a facile technique for quantitative analysis of RNA secondary structure. In general, low SHAPE signal values indicate Watson-Crick base-pairing, and high values indicate positions that are single-stranded within the RNA structure. However, the relationship of SHAPE signals to structural properties such as non-Watson-Crick base-pairing or stacking has thus far not been thoroughly investigated. Here, we present results of SHAPE experiments performed on several RNAs with published three-dimensional structures. This strategy allows us to analyze the results in terms of correlations between chemical reactivities and structural properties of the respective nucleotide, such as different types of base-pairing, stacking, and phosphate–backbone interactions. We find that the RNA SHAPE signal is strongly correlated with cis-Watson-Crick/Watson-Crick base-pairing and is to a remarkable degree not dependent on other structural properties with the exception of stacking. We subsequently generated probabilistic models that estimate the likelihood that a residue with a given SHAPE score participates in base-pairing. We show that several models that take SHAPE scores of adjacent residues into account perform better in predicting base-pairing compared with individual SHAPE scores. This underscores the context sensitivity of SHAPE and provides a framework for an improved interpretation of the response of RNA to chemical modification.
Plasma Cell Myeloma and Related Neoplasms
Authors: Lorsbach Robert B. , Hsi Eric D. , Dogan Ahmet , Fend Falko
Published: July 2011

Session 1 of the 2009 Workshop of the Society for Hematopathology/European Association of Haematopathology, Cleveland, OH, focused on plasma cell neoplasms. This report summarizes the salient diagnostic, clinical, and genetic features of plasma cell myeloma (PCM) and related neoplasms. Based on the cases submitted to the workshop, we highlight common diagnostic issues and unusual manifestations of plasma cell neoplasms, such as t(11;14)+ PCM, plasma cell leukemia, and nonsecretory plasmacytoma, as well as plasmablastic transformation of PCM. Additional issues repeatedly raised at the workshop included the differential diagnosis of extramedullary dissemination of PCM vs primary extramedullary plasmacytoma and plasmablastic lymphoma; systemic plasma cell neoplasms in immunocompromised people; and Epstein-Barr virus–associated plasma cell neoplasms. Difficult cases with borderline features presented by submitters emphasized the necessity of integrating clinical, immunophenotypic, and genetic features for appropriate classification of these disorders.
Clinical, Morphologic, Immunophenotypic, and Molecular Cytogenetic Assessment of CD4–/CD8– γδ T-Cell Large Granular Lymphocytic Leukemia
Authors: Chen Yi-Hua , Chadburn Amy , Evens Andrew M. , Winter Jane N. , Gordon Leo I. , Chenn Anjen , Goolsby Charles , Peterson LoAnn
Published: July 2011

γδ T-cell large granular lymphocytic (T-LGL) leukemia of the CD4–/CD8– subtype is rare, and data are limited in the literature. This study evaluated the clinical, morphologic, immunophenotypic, and molecular cytogenetic features of 7 cases of CD4–/CD8– γδ T-LGL leukemia. Although this variant shares several clinical and morphologic features with the more common T-LGL leukemias, the incidences of autoimmune hemolytic anemia and pure red cell aplasia are higher. Another striking feature observed in our study was the lack of increased large granular lymphocytes in the peripheral blood in the majority of cases despite prominent bone marrow or splenic involvement. CD4–/CD8– γδ T-LGL leukemia also displays an immunophenotype and pattern of splenic involvement overlapping with hepatosplenic T-cell lymphoma. Clinically, this variant of T-LGL leukemia shows an overall indolent course, but treatment is often required in the initial stages of the disease. Awareness of these features is important for early recognition and accurate diagnosis of patients with CD4–/CD8– γδ T-LGL leukemia.
Naturally occurring enzyme inhibitors and their pharmaceutical applications
Authors: Ata Athar , Naz Samina , Elias Evan M.
Published: July 2011

Enzyme inhibitors play a significant role in the drug discovery process. For instance, acetylcholinesterase (AChE) inhibitors have applications in curing Alzheimer’s disease (AD), senile dementia, ataxia, myasthenia gravis, and Parkinson’s disease. Glutathione S-transferase (GST) inhibitors have applications as adjuvants to overcome anticancer and antiparasitic drug resistance problems. Compounds inhibiting the activity of α-glucosidase are used to treat type 2 diabetes mellitus and obesity problems. This article describes the identification of natural products exhibiting AChE, GST, and α-glucosidase inhibitory activities from medicinally important plants. Additionally, structure–activity relationship (SAR) studies of these newly discovered enzyme inhibitors are also discussed.
Morphology development of polytetrafluoroethylene in a polypropylene melt (IUPAC Technical Report)
Authors: Ali Mohd Amran Bin Md , Nobukawa Shogo , Yamaguchi Masayuki
Published: July 2011

Morphology development of polytetrafluoroethylene (PTFE) caused by applied flow history in molten isotactic polypropylene (PP) is investigated, employing a cone-and-plate rheometer and a capillary rheometer as mixing devices. Since the flow history is applied at 190 °C, PTFE is in the solid state whereas PP is in the molten state. It is found that primary PTFE particles tend to be agglomerated together by mechanical interlocking. Then they are fragmented into fibers by hydrodynamic force with reorganization process of crystalline phase. The diameter of the fragmented fibers is the same as that of the original ellipsoidal particles. Further, fine fibers whose diameter is in the range from 50 to 100 nm are also generated by yielding behavior of the particles. The prolonged shearing leads to a large number of fibers, although the diameter and length are hardly affected by the exposure time of shearing and shear stress. Moreover, the flow type (i.e., drag or pressure flow) does not affect the morphology to a great extent, although the drag flow is not efficient to reduce large agglomerated particles. The fibers form an interdigitated network structure, which is responsible for the marked melt elasticity.
Local Displacement Transducer With Anderson Loop
Authors: Leong E. C. , Nyunt T. T. , Low K. S.
Published: July 2011

Wheatstone bridge has long been used in many strain-gauge based measuring instruments including the local displacement transducer. In this paper, an alternative circuit to the Wheatstone bridge, Anderson loop, for local displacement transducers is examined. Local displacement transducers were manufactured in an identical fashion but with different circuitries. In both circuitries, similar gain and filter were applied to the output signals. An identical experimental setup for both Anderson loop and Wheatstone bridge local displacement transducers was used in the evaluation, and, therefore, any differences in performances of the local displacement transducers are attributed to the circuitry. The range of displacement examined for the local displacement transducer was 0.4 mm. Self-heating of the strain gauges was found to occur regardless of the circuitry used when a high input current was used in the local displacement transducer with Anderson loop or a high input voltage was used in the local displacement transducer with Wheatstone bridge. The effects of self-heating of strain gauges are only evident in long duration tests. The local displacement transducer with Anderson loop was found to be twice as sensitive as that with Wheatstone bridge for similar input current. Furthermore, the local displacement transducer with Anderson loop outperformed the local displacement transducer with Wheatstone bridge in terms of lower deviation, hysteresis and repeatability errors.
New Three-Way Split Mold Design and Experimental Procedure for Testing Soft, Grouted Soils
Authors: El Mohtar Chadi S. , Rugg Dennis A.
Published: July 2011

Soil grouting has become a popular method for soil improvement in recent years. Grouting is generally intended to increase a soil’s strength, increase its liquefaction resistance, or reduce its hydraulic conductivity. Soil grouting involves the injection, permeation, or mechanical mixing of cementitious, silica, or clay grout into a soil deposit. With the increase in popularity of these methods comes the issue of testing grouted soils to verify the expected soil improvement. While some of the methods and materials mentioned result in soils that are sufficiently cemented to produce trimmable specimens that can stand under their own weight, other methods produce softer materials that are very difficult to sample or even to recreate and test in the lab. Preparing such soft samples in the laboratory poses two challenges: 1) if the specimen is prepared in the triaxial cell directly, the grouting process might not be feasible because of the porous stones and small diameter tubing in the triaxial cell; and 2) if the specimens are prepared outside the triaxial cell, soft specimens might not be able to stand under their own weight without significant strains and damage to the soil structure. This paper will thoroughly describe a three-way split mold specifically designed to accommodate the permeation and testing of soils that are too soft or too weak to be easily sampled or tested in the lab. A simple procedure outlining the use of this three-way split mold will also be described. Finally, the results from a series of consolidated undrained, monotonically loaded triaxial tests will be presented as an example of the split mold application. These tests utilized the new three-way split mold for sample preparation of loose Ottawa sand permeated with a thixotropic bentonite suspension.
Centrifuge Modeling of In situ Surfactant Enhanced Flushing of Diesel Contaminated Soil
Authors: Pasha Amin Yousefnia , Hu Liming , Meegoda Jay N. , Aflaki Esmail , Du Jianting
Published: July 2011

In this research the effectiveness of physical modeling of in situ flushing with water and a surfactant solution was evaluated using a geotechnical centrifuge. The centrifugal experiments consist of two parts: transport of diesel through fine grain soils and remediation of diesel contaminated soil. First, 7.74 m3 of diesel per meter (width) was infiltrated into a 15 m thick prototype layer of fine grain unsaturated soil. Then contaminated soil was remediated by continuous flushing with two liquids (water and 1% (wt/v) aqueous solution of sodium dodecyl sulfate (SDS) surfactant) while subjecting the sample to 50 g acceleration. Effectiveness of soil remediation by flushing with 1% (wt/v) SDS surfactant was investigated in this research and compared that to flushing with water without additives. The total volume of injected remediation solution over 130 prototype days was equal to 4.20 times the pore volume of the soil between two barrier walls. The results showed that when surfactant solution was used, the elutriate flow was downward congruent with the remediation goal. On the other hand, when water without surfactant was used, the contamination plume expanded in the lateral direction which exacerbated the situation. The test results also showed a considerable reduction (76.3%) of diesel content in soil after flushing with SDS solution after 130 days of flushing. Based on the test results it was concluded that the geotechnical centrifuge and the described experimental procedure could be used as a design tool for implementation and evaluating the effectiveness of in situ surfactant-enhanced flushing remediation systems.
Microstructural Interpretation of Water Content and Dry Density Influence on the DC-Electrical Resistivity of a Fine-Grained Soil
Authors: Beck Yves-Laurent , Palma Lopes Sérgio , Ferber Valéry , Côte Philippe
Published: July 2011

In geotechnical engineering, there is a need for an in situ technique for measuring density and water content of soils quickly, accurately and, preferably, in a non-destructive way. DC-electrical resistivity provides a method capable of addressing this need. A new resistivity-cell and a new experimental procedure were developed to assess the resistivity of compacted samples of a silty soil. The study was carried out over moisture content and compaction level ranges that are consistent with those acceptable in earthwork construction. In this laboratory work, the effects of dry density and gravimetric water content on the soil bulk resistivity are considered separately. Furthermore, the effect of air index on electrical resistivity is demonstrated. Our data exhibit two distinct trends separated by a “critical” water content which appears to fall very close to the standard Proctor optimum moisture content for this soil. This promising result cannot be generalized as it needs to be investigated on other soils. The experimental results are further analyzed within the context of a previously published soil microfabric model which distinguishes water phase, air phase, particles assumed to be “inert” and clayey aggregates. Two types of electrical conduction enable explaining the results: first, conduction occurring in the intra-aggregate voids, controlled by the charge density on the surface of clayey particles; and then, inter-aggregate conduction controlled by interstitial water resistivity. The relative effect of each type of conduction is shown to strongly depend on water content. Finally, an extrapolation at zero air void allows for presenting an interpretation of the intra-aggregate volume contribution to electrical conduction in dry states. This interpretation suggests a dilution effect on the adsorbed cation concentration within bound water, that is shown to be consistent with recently published research.
Detailed Analysis of the Microstructure of the Metal/Oxide Interface Region in Zircaloy-2 after Autoclave Corrosion Testing
Authors: Tejland Pia , Thuvander Mattias , Andrén Hans-Olof , Ciurea Sorina , Andersson Thomas , Dahlbäck Mats , Hallstadius Lars
Published: July 2011

Two varieties of Zircaloy-2, with different second phase particle (SPP) size distributions and different corrosion resistance, were oxidized in a steam autoclave. Transmission electron microscopy (TEM) of large thin-foil cross-sections of the oxide and the adjacent metal shows an undulating metal/oxide interface in both materials with a periodicity of slightly less than 1 μm and an amplitude of around 100 nm. The SPPs oxidize slower than the surrounding metal, and the absence of volume increase leads to void and crack formation as the SPPs become embedded in the oxide. On SPP oxidation, iron diffuses out of the particles into the surrounding oxide. A sub-oxide with an oxygen content of approximately 50 at. % and a layer thickness of about 200 nm was observed close to the metal/oxide interface. There is a 200 nm oxygen concentration gradient into the metal, from the level close to the sub-oxide of about 30 at. % down to a few atomic percent. All tin in the matrix is incorporated in the sub-oxide, and no segregation to the metal/oxide interface was found.
Experimental Investigation of the Onset of Subcooled Nucleate Boiling in an Open-Pool Nuclear Research Reactor
Authors: Mesquita Amir Z. , Costa Antonella L. , Pereira Cláubia , Veloso Maria A. F. , Reis Patrícia A. L.
Published: July 2011

The IPR-R1 TRIGA nuclear research reactor at the Nuclear Technology Development Center (CDTN), in Belo Horizonte (Brazil), is a pool type reactor. The maximum core power is 250 kW cooled by natural circulation of light water and an open surface. Fuel to coolant heat transfer patterns must be evaluated as function of the reactor power in order to assess the thermal hydraulic performance of the core. The heat generated by nuclear fission in the reactor core is transferred from fuel elements to the cooling system through the fuel/cladding (gap) and the cladding to coolant interfaces. The objective of the thermal and hydrodynamic projects of the reactors is to remove the heat safely, without producing excessive temperature in the fuel elements. The regions of the reactor core where boiling occurs at many different power levels can be determined from the heat transfer coefficient data. As the reactor core power increases the heat transfer regime from the fuel cladding to the coolant changes from single-phase natural convection to subcooled nucleate boiling. Experimental results indicated that subcooled pool boiling occurs at the cladding surface in the reactor core central channels at power levels in excess of 60 kW. However, due to the high heat transfer coefficient in subcooled boiling the cladding temperature is quite uniform along most of the active fuel rod region and do not increase very much with the reactor power. An operational computer program and a data acquisition and signal processing system were developed as part of this research project to allow on line monitoring of the operational parameters.
Microstructural Studies of Heat Treated Zr-2.5Nb Alloy for Pressure Tube Applications
Authors: Saibaba N. , Jha S. K. , Tonpe S. , Vaibhaw Kumar , Deshmukh V. , Ramana Rao S. V. , Mani Krishna K. V. , Neogy S. , Srivastava D. , Dey G. K. , Kulkarni R. V. , Rath B. B. , Ramadasan E. , Anantharaman S. A.
Published: July 2011

Zr-2.5Nb alloy is used as pressure tube material in pressurized heavy water reactors (PHWR). Generally, these pressure tubes are used in the cold drawn condition. Heat treated Zr-2.5Nb alloy pressure tubes are used in reaktor bolshoy moshchnosti kanalniy and FUGEN type of reactors. In recent times, there has been a greater interest toward increasing the life of pressure tubes in advanced reactors. In the present work, fabrication parameters were optimized to manufacture heat treated Zr-2.5Nb alloy tube. A quenching dilatometer study was performed to establish the continuous cooling transus temperature for the alloy used in this study. Heat treatment under controlled condition in a dilatometer was performed to study microstructure at different soaking temperatures and cooling rates. In the dilatometer, during gas quenching, quenching rates were varied from 0.06 to 100°C/s to assess the effect of cooling rate on resulting microstructures. Soaking temperature and cooling rates were varied to obtain martensitic microstructure with appropriate volume fractions of primary α. On the basis of the results obtained during controlled heat treatments performed in the quenching dilatometer, 883°C was selected as the soaking temperature and water as the quenching medium for the α + β quenching operation for large dimension tubes. The α + β quenched microstructures, consisting of fine martensite phase along with 20%–25% primary α volume fraction, were used for further cold deformation and subsequent aging below the recrystallization temperature. Aging at 540°C produced fully recovered and tempered structure consisting of βNb of equilibrium composition. Mechanical properties of the finished heat treated pressure tube (aged at 515°C/24 h) produced with the present route were similar to the cold work pressure tube. Tube produced with 540°C/24 h aging exhibited substantially higher yield strength value at reactor operating temperature (300°C). The bulk texture at different stages of fabrication was evaluated. The volume fraction of the primary α phase significantly controls the final texture.
Effect of Deflection Increment Size on Apparent Performance of Fiber Reinforced Concrete Beams and Panels
Authors: Bernard E. S. , Coleman R.
Published: July 2011

Post-crack performance testing of Fiber Reinforced Concrete (FRC) is commonly undertaken using beam tests, such as ASTM C1609/C1609M, or panel tests, such as ASTM C1550. Both these tests demand the use of sophisticated servo-controlled test machines with data acquisition systems that record several hundreds to thousands of points in a typical test. Existing standard test methods include detailed specifications regarding how load should be applied and how deformation is measured, but they retain simple prescriptions regarding data acquisition and the total number of points required to adequately characterize the performance of a specimen. The present investigation has been undertaken to assess the effect of changes in the size of the deflection increment between recorded points in a load-deflection curve on the apparent outcome of a test. The results indicate that the maximum increment of deflection between successively acquired data points should be 0.020 mm for a ASTM C1550 panel test and 0.0035 mm for a ASTM C1609/C1609M beam test in order to limit potential errors in energy absorption and peak load to within acceptable levels. This is smaller than the current recommendation of 0.05 mm for ASTM C1550 and thus a change to a smaller measurement interval is recommended. For ASTM C1609/C1609M the currently recommendation for rate of data acquisition over the first span/900 deflection is adequate but thereafter the rate of acquisition should be increased by 50%.
Screening of Spill and Leakage of Antibiotics in Hospital Wards
Authors: Nygren Olle , Lindahl Roger
Published: July 2011

This paper presents a two-phase study of spill and leakage of antibiotics in hospitals. The first phase was a screening of spill and leakage at 21 hospital wards in 16 hospitals. Phase two was an extended investigation, where different measures to reduce spill and leakage were implemented and a follow-up screening was made to evaluate the effect of the measures. At the screening, 206 samples were collected. The result was used to classify the wards into four classes: Low, Mean, High, and Very high. Spatial distribution patterns and the effect of compounding systems were also investigated. The screening showed that spill and leakage occur at all wards. Eleven of the 21 wards had High or Very high contamination level. This result also showed that the substances were distributed according to three possible patterns. The compounding systems also had an impact on the spill and leakage. All four wards that used a closed system were found among the six wards with the lowest spill and leakage, while all three wards that used open venting systems were found among the six wards with the highest spill and leakage. The result also showed that it is possible to handle antibiotics with only insignificant spill and leakage, i.e., by using closed systems. Three wards, classified as Very high, were included in the second phase. Measures to decrease spill and leakage and reduce the distribution the substances were implemented. After two month, a follow-up screening was carried out. The result showed lower contamination levels at all three wards and the implemented measures had some effect. Simple and easy-to-do measures can contribute to reduce the spill and leakage that occur. There is still, however, a need to discuss how to handle antibiotics in a safe way to reduce possible spill and leakage and to prevent the distribution of this spill and leakage.
Use of Direct Reading Surface Sampling Methods for Site Characterization and Remediation of Methamphetamine Contaminated Properties
Authors: Snawder John E , Striley Cynthia AF , Esswein Eric J , Hessel Jeremy , Sammons Deborah L , Robertson Shirley A , Johnson Belinda C , MacKenzie Barbara A , Smith Jerry P , Walker Cynthia V
Published: July 2011

Residual methamphetamine contamination in Clandestine laboratories represents a hazard to emergency response personnel, remediation workers and the general public. To address this threat, two rapid, sensitive surface sampling techniques to assess the location and level of methamphetamine contamination were developed. Both methods employ established industrial hygiene surface sampling materials (wipes and swabs) but differ in their sensitivity and detection technology. One method, based on colorimetric disclosure, detects and confirms a collected sample or visible residues. The second method uses a lateral flow immunochemical assay (LFIA) for semi-quantitative detection of trace contamination. The National Institute for Occupational Safety and Health (NIOSH) partnered with public health agencies to develop applications of the methods for assessment of methamphetamine contamination of suspected properties. These applications focused on safe strategies for site assessment, hazard characterization, and remediation effectiveness. To conduct the field studies, NIOSH researchers and their partners visited more than a dozen suspected laboratories including mobile labs, abandoned properties, occupied residences, and motel rooms. NIOSH found greater than 95% agreement between positive identification of the presence of methamphetamine by LFIA and laboratory-based, liquid chromatography mass spectroscopy (LC–MS) methods. Test results were used to develop site assessments and make personal protective equipment recommendations. Results were also used to conduct process-based decontamination of properties and to make health-based decisions on remediation, re-occupancy of residences, as well as determine the degree of contamination of personal property in an inactive clandestine laboratory. By partnering with stakeholders, NIOSH was able to achieve two primary goals: (1) to develop a level of awareness in health department sanitarians, law enforcement personnel and other first responders that methamphetamine surface contamination was a potentially significant route of exposure; (2) to validate our methods in the field and to develop protocols for proper use and interpretation of the results.
Use of the ASTM Inter-Laboratory Studies (ILS) Program in Developing Precision Data for ASTM D5755 – Asbestos in Dust by Microvacuum Sampling
Authors: Millette James R.
Published: July 2011

ASTM Standard D5755 “Standard Test Method for Microvacuum Sampling and Indirect Analysis of Dust by Transmission Electron Microscopy (TEM) for Asbestos Structure Number Concentration” uses a microvacuuming sampling procedure and transmission electron microscopy analysis to (a) identify asbestos in surface dust and (b) provide an estimate of the surface loading of asbestos in the sampled dust reported as the number of asbestos structures per unit area of sampled surface. In a precision study of the method, ten laboratories analyzed chrysotile asbestos-containing World Trade Center dust that had been resuspended in a test room and collected off of non-asbestos floor tiles following the microvacuum cassette (microvac) collection procedures described in ASTM D5755. Each laboratory analyzed the same sample twice. The Inter-Laboratory Studies (ILS) Group of ASTM International performed the statistical examination of the data set and found a repeatability limit (r) of 61.80 and a reproducibility limit (R) of 239.30. The study data was also used to calculate coefficients of variation of 0.15 intra-laboratory and 0.6 inter-laboratory.
Development of a Method for Screening Spill and Leakage of Antibiotics on Surfaces Based on Wipe Sampling and HPLC-MS/MS Analysis
Authors: Nygren Olle , Lindahl Roger
Published: July 2011

A screening method for determination of spill and leakage of 12 different antibiotic substances has been developed. The method is based on wipe sampling where the sampling procedure has been simplified for screening purposes. After sample processing, the antibiotic substances are determined by liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). Twelve antibiotic substances can be determined in the screening method: Cefadroxil, Cefalexin, Ciprofloxacin, Demeclocyklin HCl, Diaveridin, Doxycyklin, Enrofloxacin, Flukonazol, Metronidazol, Norfloxacin, Ofloxacin, and Trimetoprim. These substances are active components in antibiotic drugs frequently used in Sweden. For screening investigations using collection of wipe samples, good or acceptable performance was obtained for ten substances on three or more surface materials. Although not fully acceptable, useful performance for screening purposes was also obtained on the other surface materials and for the other substances, except Demeclocyklin HCl, on all surface materials. By employing a classification procedure, where the samples are divided into groups according to increasing contamination of the sample surfaces, screening samples and the contamination level can simply be compared. This classification procedure will also help to circumvent any deficiency in recovery performance for some substances and surface materials.
Characteristics of a Coal Fly Ash Subjected to Additional Processing
Authors: Swan Christopher W. , Neil Chelsea W.
Published: July 2011

This paper presents the results of a study of the physical and environmental properties of pre- and post-processed fly ashes (termed Raw and Processed fly ashes, respectively). The ashes were collected from a coal-fired power plant in the northeastern U.S. which utilizes a carbon burn-out unit (CBO) to prepare the fly ash for concrete and other construction applications. Measured physical properties included carbon contents via loss-on-ignition (LOI), specific gravities, gradation analyses, and scanning electron microscopy (SEM). In addition, total and leachable concentrations of lead, selenium, and arsenic were determined. Leachable concentrations were determined for leaching solution pHs varying between 1.5 and 11.5. When compared to Processed fly ash, Raw fly ashes had an expectedly higher LOI (approximately 2% versus 6% carbon content, respectively) and lower specific gravity (2.37 versus 2.18, respectively). Although the total metal content of the fly ashes was similar, leachable metal concentrations were notably higher for the Processed fly ash over the full range of leaching solution pHs evaluated. The test results indicate that the CBO process, at times necessary to create usable fly ash, can result in fly ashes with notably altered physiochemical properties that lead to higher leachable contaminant concentrations.
Review of Standards for Surface and Dermal Sampling
Authors: Ashley Kevin , Brisson Michael J. , White Kenneth T.
Published: July 2011

This article summarizes the body of available standards for sampling of chemical and biological agents on workplace surfaces, including skin. These standards consist of voluntary consensus standards such as those promulgated by ASTM International, the International Organization for Standardization (ISO), and the European Committee for Standardization (CEN), as well as methods produced by U.S. Federal agencies such as the National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA). Gaps in availabilities of standards are discussed along with activities underway to address needs in the field of occupational and environmental hygiene. In many cases, the available standards have been developed largely in response to regulatory requirements. For example, ASTM International standards, which describe requirements for wiping surfaces and methodologies for determining metals and metalloids such as lead and beryllium, were produced primarily in response to regulatory requirements for sampling settled dust for these elements in the United States. Methods for collection of asbestos samples, vacuum sampling, dry wipe sampling, and bulk sampling have also been promulgated. Standardized methods for non-metal contaminants and biological agents are more limited in availability. In particular, there is a lack of standardized methodologies for dermal sampling and limited standard guidance on selection of appropriate surface sampling methods and data evaluation. Activities are currently ongoing within ASTM International and ISO to address some of the gaps, but additional activity is needed to address remaining requirements for consensus standards.
Nuclear radioactive techniques applied to materials research
Authors: Correia J. G. , Johnston K. , Wahl U.
Published: July 2011

In this paper we review materials characterization techniques using radioactive isotopes at the ISOLDE/CERN facility. At ISOLDE intense beams of chemically clean radioactive isotopes are provided by selective ion-sources and high-resolution isotope separators, which are coupled on-line with particle accelerators. There, new experiments are performed by an increasing number of materials researchers, which use nuclear spectroscopic techniques such as Mössbauer, perturbed angular correlations (PAC), β-NMR and emission channeling with short-lived isotopes not available elsewhere. Additionally, diffusion studies and traditionally non-radioactive techniques as deep level transient spectroscopy, Hall effect and photoluminescence measurements are performed on radioactive doped samples, providing in this way the element signature upon correlation of the time dependence of the signal with the isotope transmutation half-life. Current developments, applications and perspectives of using radioactive ion beams and techniques in solid state and biophysics research are presented with a few examples.
Nuclear structure and reaction studies near doubly magic 270Hs
Authors: Türler A.
Published: July 2011

Fast on-line gas chemical separations of Hs (hassium, element 108) in the form of HsO4 were applied to investigate the reactions 26Mg + 248Cm and 36S + 238U. In an experiment at the gas-filled separator DGFRS the reaction 48Ca + 226Ra was studied. In all cases the product of complete nuclear fusion is 274Hs*. For the first time, the new nuclide 270Hs was produced in the 4n evaporation channel and its decay properties investigated. The nuclide 270Hs was predicted by microscopic-macroscopic calculations to be a deformed doubly magic nucleus and its decay properties are therefore of special interest to theory. Also, much more detailed information was gained on the decay of 269Hs and its daughters, which led to a new assignment of decay properties of the daughter nuclides 265Sg and 261Rf. There is evidence fo r isomeric states in 265Sg and 261Rf, while 266Sg is not an alpha-particle emitter as believed previously, but decays by spontaneous fission (SF) with a rather short half-life. Also, interesting features of the used reaction 26Mg + 248Cm led to the discovery of the nucleus 271Hs in the same experiments. An investigation of the influence of the Q-value on the fusion reaction in relation to the location of the fusion barrier showed, that the high binding energy of 48Ca largely compensates for the lower fusion probability compared to more asymmetric reactions, while 36S is not as promising as a projectile.
Jews and New Religious Movements: An Introductory Essay
Authors: Ariel Yaakov
Published: July 2011

Throughout the modern era, Jews have established a series of new religious movements that in general have represented the influence of changing social and cultural realities on Jewish communal expressions. Since the 1960s, a number of new Jewish movements have utilized neo-Hasidic teachings to re-engage Jews in the spiritual elements of their tradition. Many Jews have also shown interest in new religious movements outside the Jewish fold, often playing a disproportionately large role in such groups. Bringing certain preferences and sensitivities with them, Jews who have joined such groups have often wished to retain some of their Jewish heritage and opted to combine their Jewish identity with their newly formed communities and practices. The Jewish venture into new religious movements has ultimately expanded the boundaries of Jewish life and the varieties of Jewish expressions, complicating formerly perceived notions of Jewish choices and affiliations.
Onset of effects of testosterone treatment and time span until maximum effects are achieved
Authors: Saad Farid , Aversa Antonio , Isidori Andrea M , Zafalon Livia , Zitzmann Michael , Gooren Louis
Published: July 2011

Objective

Testosterone has a spectrum of effects on the male organism. This review attempts to determine, from published studies, the time-course of the effects induced by testosterone replacement therapy from their first manifestation until maximum effects are attained.

Design

Literature data on testosterone replacement.

Results

Effects on sexual interest appear after 3 weeks plateauing at 6 weeks, with no further increments expected beyond. Changes in erections/ejaculations may require up to 6 months. Effects on quality of life manifest within 3–4 weeks, but maximum benefits take longer. Effects on depressive mood become detectable after 3–6 weeks with a maximum after 18–30 weeks. Effects on erythropoiesis are evident at 3 months, peaking at 9–12 months. Prostate-specific antigen and volume rise, marginally, plateauing at 12 months; further increase should be related to aging rather than therapy. Effects on lipids appear after 4 weeks, maximal after 6–12 months. Insulin sensitivity may improve within few days, but effects on glycemic control become evident only after 3–12 months. Changes in fat mass, lean body mass, and muscle strength occur within 12–16 weeks, stabilize at 6–12 months, but can marginally continue over years. Effects on inflammation occur within 3–12 weeks. Effects on bone are detectable already after 6 months while continuing at least for 3 years.

Conclusion

The time-course of the spectrum of effects of testosterone shows considerable variation, probably related to pharmacodynamics of the testosterone preparation. Genomic and non-genomic effects, androgen receptor polymorphism and intracellular steroid metabolism further contribute to such diversity.
Phenotype–genotype correlation and follow-up in adult patients with hypokalaemia of renal origin suggesting Gitelman syndrome
Authors: Balavoine A S , Bataille P , Vanhille P , Azar R , Noël C , Asseman P , Soudan B , Wémeau J L , Vantyghem M C
Published: July 2011

Introduction

Gitelman syndrome (GS) is a tubulopathy caused bySLC12A3gene mutations, which lead to hypokalaemic alkalosis, secondary hyperaldosteronism, hypomagnesaemia and hypocalciuria.

Aim

The aim of this study was to assess the prevalence ofSLC12A3gene mutations in adult hypokalaemic patients; to compare the phenotype of homozygous, heterozygous and non-mutated patients; and to determine the efficiency of treatment.

Methods

Clinical, biological and genetic data were recorded in 26 patients.

Results

Screening for theSLC12A3gene detected two mutations in 15 patients (six homozygous and nine compound heterozygous), one mutation in six patients and no mutation in five patients. There was no statistical difference in clinical symptoms at diagnosis between the three groups. Systolic blood pressure tended to be lower in patients with two mutations (P=0.16). Hypertension was unexpectedly detected in four patients. Five patients with two mutated alleles and two with heterozygosity had severe manifestations of GS. Significant differences were observed between the three groups in blood potassium, chloride, magnesium, supine aldosterone, 24 h urine chloride and magnesium levels and in modification of the diet in renal disease. Mean blood potassium levels increased from 2.8±0.3, 3.5±0.5 and 3.2±0.3 before treatment to 3.2±0.5, 3.7±0.6 and 3.7±0.3 mmol/l with treatment in groups with two (P=0.003), one and no mutated alleles respectively.

Conclusion

In adult patients referred for renal hypokalaemia, we confirmed the presence of mutations of theSLC12A3gene in 80% of cases. GS was more severe in patients with two mutated alleles than in those with one or no mutated alleles. High blood pressure should not rule out the diagnosis, especially in older patients.
Pregnancy-associated plasma protein A in obese children: relationship to markers and risk factors of atherosclerosis and members of the IGF system
Authors: Woelfle Joachim , Roth Christian L , Wunsch Rainer , Reinehr Thomas
Published: July 2011

Background

Pregnancy-associated plasma protein A (PAPPA) is a large placenta-derived glycoprotein, which serves as a protease of several IGF-binding proteins (IGFBPs). In non-pregnant adults, measurable PAPPA levels were detected and have been implicated in the pathophysiology of atherosclerotic plaques. However, data in children is lacking.

Objective

To study the relationship between PAPPA, markers of atherosclerosis, and members of the IGF system in pediatric obesity.

Patients and design

Eighty-two obese and 52 nonobese children and 1-year longitudinal follow-up study for obese cohort.

Intervention

Outpatient 1-year intervention program based on exercise, behavior, and nutrition therapy.

Main outcome measures

Changes in PAPPA levels, carotid intima media thickness (IMT), weight, blood pressure, lipids, metabolic markers, and members of IGF system.

Results

Baseline PAPPA (PAPPABL) serum levels did not differ between obese and lean subjects. PAPPABLcorrelated significantly with IGF1, IGFBP1, and serum cholesterol. During the 1-year-program mean IMT decreased from 0.66±0.01 to 0.63±0.01 mm (P<0.05) and PAPPA from 1.83±0.12 to 1.58±0.11 μU/l (P<0.00). In linear regression analysis with IMT after intervention as dependent variable, PAPPA contributed significantly to the observed variance. The longitudinal change of PAPPA correlated significantly with the change of serum triglycerides.

Conclusion

In this cohort of obese children, PAPPA serum levels correlated significantly with other cardiovascular risk factors. The lack of a direct correlation between PAPPA and IMT suggests that the described association of atherosclerotic plaques and increased PAPPA levels might reflect an indirect mechanism of PAPPA with cardiovascular risk factors such as serum lipids rather than a direct effect on the vasculature.
Intussusception, Rotavirus, and Oral Vaccines: Summary of a Workshop
Authors: Peter Georges , Myers Martin G.
Published: July 2011

Rotavirus gastroenteritis continues to cause substantial morbidity and mortality worldwide, despite widespread breastfeeding and use of oral rehydration therapy. This burden of disease indicates that an effective, safe rotavirus vaccine is needed, and in 1998 the first rhesus-human reassortant rotavirus tetravalent vaccine, Rotashield, was licensed in the United States. However, the recommendations for its use were withdrawn in 1999 because of the recognition of an uncommon but serious adverse event, intussusception. A workshop in September 2001 was held to review the subsequent developments and research regarding this association, the proceedings of which are summarized here. Although the pathogenesis of this association remains unknown, epidemiologic evidence supports a causal relationship, with a population attributable risk of ∼1 per 10 000 (range of 1 in 5000 to 1 in 12 000) vaccine recipients. Whether this association will exist with other candidate rotavirus vaccine strains and whether the attributable risk for intussusception would be similar in other populations administered this vaccine are unclear. Because perceptions of vaccine safety derive from the relative disease burdens of the illness prevented and adverse events induced, the acceptance of rare adverse events may vary substantially in different settings. Nevertheless, a continuing consensus on the need for a safe and effective vaccine to prevent rotavirus gastroenteritis, especially for use in developing countries, exists.