bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental Failure Effect Analysis of Composite High-Speed Flywheel Rotors
Authors: Fischer G , Grothaus R , Hufenbach W 
Published: April 2008

Due to their high specific strength and the possibility of creating a load-adapted property profile, composite materials are ideally suited for the design of high-speed flywheel rotors. The rotors are exposed to extreme loading conditions by high centrifugal forces, partially superposed by elevated temperatures due to an integrated electrical machine, bearings or air friction.
A sophisticated fail-safe design of composite flywheel rotors has been applied here, which allows the rotor to fail catastrophically. To withstand the manifold burst behavior safely the exact loading of the containment must be known within a simultaneous engineering approach of rotor and containment. Therefore, adapted rotor rigs and devices for measuring the burst effects in the axial, radial and circumferential direction have been designed and successfully tested. Experimental failure studies on the fiber composite flywheel rims prove the manifold burst behavior and containment interactions. Extreme axial shock waves due to the composite fragment movement have been measured experimentally, which are principally not known for isotropic rotor failure.
Assessment of Composite Containment Loadings by an Adapted Failure Effect Analysis
Authors: Hufenbach W , Grothaus R 
Published: April 2008

Principal different rotor failure modes require adapted design approaches for the design of composite containments. The Hagg/Shankey approach considers the brittle fracture of isotropic rotors and the subsequent impact of large fragments in containment rings. Other approaches are based on multi-fragmentation, which is typical for rotors made of composite materials. This failure mode assumes a composite dust rather than large fragments. The physical model is more complex and only first semi-empirical ideas have been formulated to describe the post-failure effects on the containment.
The composite dust has the potential to cause a carbon dust explosion but rather often also results in a composite particle flow. This latter effect has already been observed in practical applications. Due to recent advances in experimental composite rotor failure assessment, this manifold burst behavior with axial shock waves not known for metallic rotors, could be proved principally.
Two different theories to analyze these “dust” failure effects are theoretically analyzed concerning their physical plausibility. A comparison with experimental data is presented and the general assessment of these semi-empirical approaches is used to estimate containment loading limits.
Long-Term Strain-Corrosion Behavior in RPM Sewer Pipes
Authors: Hopkins SW , Duffner DH , Johnston PR , McGarry FJ 
Published: April 2008

The mechanical properties of reinforced plastic mortar (RPM) pipe material are typically measured prior to production in order to establish design properties, and during production to ensure quality of the pipe material. Seldom does the opportunity become available to measure the mechanical properties of service-aged (conditioned) components. In this paper, the short-term properties of the service-aged pipes are compared with the original production specifications. The long-term, strain-corrosion cracking properties have also been measured during the past 10 years on these service-aged pipes. Some laboratory specimens still have not failed after 10 years under test.
Reinforced plastic mortar (RPM) pipes were excavated from the ground after about 15 years of sewer service, and material coupons from these pipes were subjected to various mechanical tests. Axial-direction tensile tests, hoop-direction stiffness, and acid strain-corrosion testing were performed. The acid strain corrosion tests were monitored as a function of time until failure. The resulting lifetimes were related to the initial surface strains and showed a decreasing logarithmic relationship for both concentrations of the sulfuric acid solutions. Some pipe samples have been under test for 10 years, and prior to this testing were buried in the ground, and used as sewer pipes for 15 years.
The failed laboratory specimens were compared by fractographic examination with those from in-service failures. Laboratory specimens that failed in shorter times appeared to be overload in nature and exhibited little, if any, time-dependent fracture surface features. In-service failures indicate that the crack had been present for a significant time. Comparisons are also made between the observed fractographic appearance of the fibers and the laboratory failure time for both pH values.
Transplantation of Bone Marrow-Derived Very Small Embryonic-Like Stem Cells Attenuates Left Ventricular Dysfunction and Remodeling After Myocardial Infarction
Authors: Dawn Buddhadeb , Tiwari Sumit , Kucia Magdalena J. , Zuba-Surma Ewa K. , Guo Yiru , SanganalMath Santosh K. , Abdel-Latif Ahmed , Hunt Greg , Vincent Robert J. , Taher Hisham , Reed Nathan J. , Ratajczak Mariusz Z. , Bolli Roberto 
Published: April 2008

Abstract
Adult bone marrow (BM) contains Sca-1+/Lin−/CD45− very small embryonic-like stem cells (VSELs) that express markers of several lineages, including cardiac markers, and differentiate into cardiomyocytes in vitro. We examined whether BM-derived VSELs promote myocardial repair after a reperfused myocardial infarction (MI). Mice underwent a 30-minute coronary occlusion followed by reperfusion and received intramyocardial injection of vehicle (n= 11), 1 × 105 Sca-1+/Lin−/CD45+ enhanced green fluorescent protein (EGFP)-labeled hematopoietic stem cells (n= 13 [cell control group]), or 1 × 104 Sca-1+/Lin−/CD45− EGFP-labeled cells (n= 14 [VSEL-treated group]) at 48 hours after MI. At 35 days after MI, VSEL-treated mice exhibited improved global and regional left ventricular (LV) systolic function (echocardiography) and attenuated myocyte hypertrophy in surviving tissue (histology and echocardiography) compared with vehicle-treated controls. In contrast, transplantation of Sca-1+/Lin−/CD45+ cells failed to confer any functional or structural benefits. Scattered EGFP+ myocytes and capillaries were present in the infarct region in VSEL-treated mice, but their numbers were very small. These results indicate that transplantation of a relatively small number of CD45− VSELs is sufficient to improve LV function and alleviate myocyte hypertrophy after MI, supporting the potential therapeutic utility of these cells for cardiac repair.
Disclosure of potential conflicts of interest is found at the end of this article.
Transforming Growth Factor β Cooperates with Persephin for Dopaminergic Phenotype Induction
Authors: Roussa Eleni , Oehlke Oliver , Rahhal Belal , Heermann Stephan , Heidrich Stefanie , Wiehle Michael , Krieglstein Kerstin 
Published: April 2008

Abstract
The aim of the present study was to investigate the putative cooperative effects of transforming growth factor β (TGF-β) and glial cell line-derived neurotrophic factor (GDNF) family ligands in the differentiation of midbrain progenitors toward a dopaminergic phenotype. Therefore, a mouse midbrain embryonic day (E) 12 neurospheres culture was used as an experimental model. We show that neurturin and persephin (PSPN), but not GDNF, are capable of transient induction of dopaminergic neurons in vitro. This process, however, requires the presence of endogenous TGF-β. In contrast, after 8 days in vitro GDNF rescued the TGF-β neutralization-dependent loss of the TH-positive cells. In vivo, at E14.5, no apparent phenotype concerning dopaminergic neurons was observed in Tgf-β2−/−/gdnf−/− double mutant mice. In vitro, combined TGF-β/PSPN treatment achieved a yield of approximately 20% TH-positive cells that were less vulnerable against 1-methyl-4-phenyl pyridinium ion toxicity. The underlying TGF-β/PSPN differentiation signaling is receptor-mediated, involving p38 mitogen-activated protein kinase and phosphatidylinositol 3-kinase pathways. These results indicate that phenotype induction and survival of fully differentiated neurons are accomplished through distinct pathways and individual factor requirement. TGF-β is required for the induction of dopaminergic neurons, whereas GDNF is required for regulating and/or maintaining a differentiated neuronal phenotype. Moreover, this study suggests that the combination of TGF-β with PSPN is a potent inductive cocktail for the generation of dopaminergic neurons that should be considered in tissue engineering and cell replacement therapies for Parkinson's disease.
Disclosure of potential conflicts of interest is found at the end of this article.
Novel Cardiac Precursor-Like Cells from Human Menstrual Blood-Derived Mesenchymal Cells
Authors: Hida Naoko , Nishiyama Nobuhiro , Miyoshi Shunichiro , Kira Shinichiro , Segawa Kaoru , Uyama Taro , Mori Taisuke , Miyado Kenji , Ikegami Yukinori , Cui ChangHao , Kiyono Tohru , Kyo Satoru , Shimizu Tatsuya , Okano Teruo , Sakamoto Michiie , Ogawa Satoshi , Umezawa Akihiro 
Published: April 2008

Abstract
Stem cell therapy can help repair damaged heart tissue. Yet many of the suitable cells currently identified for human use are difficult to obtain and involve invasive procedures. In our search for novel stem cells with a higher cardiomyogenic potential than those available from bone marrow, we discovered that potent cardiac precursor-like cells can be harvested from human menstrual blood. This represents a new, noninvasive, and potent source of cardiac stem cell therapeutic material. We demonstrate that menstrual blood-derived mesenchymal cells (MMCs) began beating spontaneously after induction, exhibiting cardiomyocyte-specific action potentials. Cardiac troponin-I-positive cardiomyocytes accounted for 27%–32% of the MMCs in vitro. The MMCs proliferated, on average, 28 generations without affecting cardiomyogenic transdifferentiation ability, and expressed mRNA of GATA-4 before cardiomyogenic induction. Hypothesizing that the majority of cardiomyogenic cells in MMCs originated from detached uterine endometrial glands, we established monoclonal endometrial gland-derived mesenchymal cells (EMCs), 76%–97% of which transdifferentiated into cardiac cells in vitro. Both EMCs and MMCs were positive for CD29, CD105 and negative for CD34, CD45. EMCs engrafted onto a recipient's heart using a novel 3-dimensional EMC cell sheet manipulation transdifferentiated into cardiac tissue layer in vivo. Transplanted MMCs also significantly restored impaired cardiac function, decreasing the myocardial infarction (MI) area in the nude rat model, with tissue of MMC-derived cardiomyocytes observed in the MI area in vivo. Thus, MMCs appear to be a potential novel, easily accessible source of material for cardiac stem cell-based therapy.
Disclosure of potential conflicts of interest is found at the end of this article.
Lineage Selection of Functional and Cryopreservable Human Embryonic Stem Cell-Derived Neurons
Authors: Ladewig Julia , Koch Philipp , Endl Elmar , Meiners Banu , Opitz Thoralf , Couillard-Despres Sebastien , Aigner Ludwig , Brüstle Oliver 
Published: April 2008

Abstract
A major prerequisite for the biomedical application of human embryonic stem cells (hESC) is the derivation of defined and homogeneous somatic cell types. Here we present a human doublecortin (DCX) promoter-based lineage-selection strategy for the generation of purified hESC-derived immature neurons. After transfection of hESC-derived neural precursors with a DCX-enhanced green fluorescent protein construct, fluorescence-activated cell sorting enables the enrichment of immature human neurons at purities of up to 95%. Selected neurons undergo functional maturation and are able to establish synaptic connections. Considering that the applicability of purified hESC-derived neurons would largely benefit from an efficient cryopreservation technique, we set out to devise defined freezing conditions involving caspase inhibition, which yield post-thaw recovery rates of up to 83%. Combined with our lineage-selection procedure this cryopreservation technique enables the generation of human neurons in a ready-to-use format for a large variety of biomedical applications.
Disclosure of potential conflicts of interest is found at the end of this article.
Modeling the environmental fate of perfluorooctanoate and its precursors from global fluorotelomer acrylate polymer use
Authors: van Zelm Rosalie , Huijbregts Mark A.J , Russell Mark H , Jager Tjalling , van de Meent Dik 
Published: April 2008

AbstractThe environment contains various direct and indirect sources of perfluorooctanoic acid (PFOA). The present study uses a dynamic multispecies environmental fate model to analyze the potential formation of perfluorooctanoate (PFO), the anion of PFOA, in the environment from fluorotelomer acrylate polymer (FTacrylate) emitted to landfills and wastewater, residual fluorotelomer alcohol (8:2 FTOH) in FTacrylate, and residual PFOA in FTacrylate. A multispecies version of the SimpleBox model, which is capable of determining the fate of a chemical and its degradation products, was developed for this purpose. An uncertainty analysis on the chemical-specific input parameters was performed to examine for uncertainty in modeled concentrations. In 2005, residual 8:2 FTOH made up 80% of the total contribution of FTacrylate use to PFO concentrations in global oceans, and residual PFOA in FTacrylate contributed 15% to PFO concentrations from FTacrylate use in global oceans. After hundreds of years, however, the main source of PFO from total historical FTacrylate production is predicted to be FTacrylate degrading in soil following land application of sludge from sewage treatment plants, followed by FTacrylate still present in landfills. Uncertainty in modeled PFO concentrations was up to a factor of 3.3. Current FTacrylate use contributes less than 1% of the PFO in seawater, but because direct PFOA emission sources are reduced and PFOA continues to be formed from FTacrylate in soil and in landfills, this fraction grows over time.
The Lean Profile: A Step Change in Drilling Performance
Authors: Calderoni A. , Ligrone A. , Molaschi C. 
Published: April 2008

Abstract
With the conventional drilling technique, a general rule-of-thumb establishes that the surface and intermediate casing strings are to be run in holes with a diameter of up to 6-7 in. larger than the casing.
This rule is based on the fact that: it is difficult to drill a straight vertical well withconventional technologies;the larger the casing diameter the stiffer the casingstring.
The clearance between casing and open hole is then reduced to about 1" for the deeper sections, because of the higher flexibility of the casing strings.
This paper presents the "Lean Profile", an innovative drilling technique which aims at maintaining 1" clearance throughout the whole casing program, leading to a slimmer well profile but keeping the same size for the production casing string. To achieve this it is mandatory to adopt suitable drilling technologies that will be deeply discussed in the paper.
The "Lean Profile" has been successfully applied to some wells drilled from on-shore clusters with parallel vertical sections long as much as 2,000 meters. The drilling environment is challenging with problems such as formations' tendency to deviate from the vertical trajectory, wellbore instability and circulation losses.
In this operating scenario the "Lean Profile" provided for dramatic time and cost reduction. In fact, the halving of the rock volume involved in the drilling process resulted in an outstanding drilling performance (-40% on drilling time with respect to standard technology), less material consumption and less waste production.
The Lean Profile is part of the drilling strategy for some 30 wells in the Val d'Agri, southern Italy, with interesting cost saving opportunities.
This paper summarizes experiences and results from the field along with engineering considerations.
The Potential of Group Visits in Diabetes Care
Authors: Davis Andrew M. , Sawyer Devin R. , Vinci Lisa M. 
Published: April 2008

IN BRIEFCompared to more ambitious practice redesign, group visits are a relatively straightforward innovation that offer promise in improving efficiency and encouraging patient self-management. This article reviews recent literature and explores practical issues from the authors' experience in a Midwest academic medical center and a West Coast family medicine residency.
Dissection and Culture of Embryonic Spinal Commissural Neurons
Authors: Moore Simon W. , Kennedy Timothy E. 
Published: April 2008

AbstractStudies of spinal commissural neurons have provided substantial insight into the mechanisms that regulate axon guidance. Explants of embryonic spinal cords and isolated spinal commissural neurons have been important experimental tools for the identification and characterization of several guidance cues, including netrins, semaphorins, slits, sonic hedgehog, BMPs, and wnts. In this unit, protocols are provided for establishing these explant assays to assess the outgrowth and turning capacity of commissural axons. In addition, methods are included for preparing cultures highly enriched with embryonic commissural neurons, which have been used to probe the biochemical signaling mechanisms regulating axon guidance. Curr. Protoc. Neurosci. 43:3.20.1‐3.20.17. © 2008 by John Wiley & Sons, Inc.
EMS and UV Mutagenesis in Yeast
Authors: Winston Fred 
Published: April 2008

AbstractMany fundamental biological processes have been elucidated by the isolation and analysis of mutants that are defective in such processes. Therefore, the methods to generate mutants are of great importance in model organisms. This unit describes two protocols for mutagenesis of yeast—using ethyl methanesulfate (EMS) and ultraviolet (UV) light. Each of these methods has been used successfully for many years. Curr. Protoc. Mol. Biol. 82:13.3B.1‐13.3B.5. © 2008 by John Wiley & Sons, Inc.
Using CellProfiler for Automatic Identification and Measurement of Biological Objects in Images
Authors: Vokes Martha S. , Carpenter Anne E. 
Published: April 2008

AbstractVisual analysis is required to perform many biological experiments, from counting yeast colonies to measuring the size and shape of individual cells or the intensity of fluorescently labeled proteins within them. This unit outlines the use of CellProfiler, a free, open‐source image analysis tool that extracts quantitative information from biological images. It includes a step‐by‐step protocol for automated analysis of the number, color, and size of yeast colonies growing on agar plates, but the methods can be adapted to identify and measure any objects in images. The flexibility of the software allows users to tailor pipelines of adjustable modules to fit different biological experiments, to generate accurate measurements from dozens or even hundreds of thousands of images. Curr. Protoc. Mol. Biol. 82:14.17.1‐14.17.12. © 2008 by John Wiley & Sons, Inc.
Production of a Heterozygous Mutant Cell Line by Homologous Recombination (Single Knockout)
Authors: Mortensen Richard 
Published: April 2008

AbstractGene targeting by homologous recombination is a powerful and widely used technique for introduction of specific gene mutations (frequently a gene inactivation) in transgenic animals. The basic method detailed in this unit uses sequences homologous to the endogenous gene flanking the mutation. While methods using bacterial artificial chromosomes (BACs) and recombineering may be used, in most cases simpler bacterial plasmid clones with several kb of homology are sufficient. This protocol details the strategic factors in designing the constructs for selection and screening for homologous recombination. Curr. Protoc. Mol. Biol. 82:23.5.1‐23.5.11. © 2008 by John Wiley & Sons, Inc.
Production of a Homozygous Mutant Embryonic Stem Cell Line (Double Knockout)
Authors: Mortensen Richard 
Published: April 2008

AbstractUnder some circumstances, it may be desirable to produce a mouse cell clone in which both alleles of a desired gene are mutated. This may be because the mutation causes embryonic lethality in homozygous animals, or to test cultured cells before an animal is produced. This protocol details an easy method for obtaining homozygous cells by homologous recombination without the need for two targeting events. Curr. Protoc. Mol. Biol. 82:23.6.1‐23.6.4. © 2008 by John Wiley & Sons, Inc.
Calculation and Use of the Hardy‐Weinberg Model in Association Studies
Authors: Ryckman Kelli , Williams Scott M. 
Published: April 2008

AbstractHardy‐Weinberg equilibrium (HWE) is an important tool for understanding population structure. If certain assumptions are met, genotype and allele frequencies can be estimated from one generation to the next. In genetic association studies, HWE principles have been applied to detect genotyping error and disease susceptibility loci. The focus of this unit is to review the key principles and assumptions of HWE. There is a brief discussion on how the significance of HWE is tested, and a review of current applications of HWE in association studies. The applications discussed include estimating penetrance, evaluating genotyping errors, testing for population stratification, and testing for association. Curr. Protoc. Hum. Genet. 57:1.18.1‐1.18.11. © 2008 by John Wiley & Sons, Inc.
p53 Testing for Li‐Fraumeni and Li‐Fraumeni‐Like Syndromes
Authors: Gonzalez Kelly , Fong Cindy , Buzin Carolyn , Sommer Steve S. , Saldivar Juan‐Sebastian 
Published: April 2008

AbstractLi‐Fraumeni Syndrome (LFS; OMIM #151623) is an autosomal dominant cancer predisposition syndrome characterized by early onset tumors including sarcomas, breast cancer, leukemia, brain tumors, and adrenocortical carcinoma. Li‐Fraumeni syndrome is primarily attributed to germline mutations in the p53 tumor suppressor gene, which encodes tumor protein 53. In addition to germline p53 mutations, the p53 gene is the most commonly mutated gene in human cancers, with as much as 50% of tumors containing somatic p53 mutations. This unit provides a protocol to perform germline mutation analysis of the p53 gene. The protocol includes steps for amplification and sequencing of the entire coding region of the p53 gene (exons 2 to 11). The protocol was designed for detecting germline alterations from DNA extracted from blood; however, with some additional optimization, it could also be used to detect somatic mutations in DNA extracted from tumors. Curr. Protoc. Hum. Genet. 57:10.10.1‐10.10.11. © 2008 by John Wiley & Sons, Inc.
Parallel high‐resolution finite volume simulation of particulate processes
Authors: Gunawan Rudiyanto , Fusman Irene , Braatz Richard D. 
Published: April 2008

AbstractPopulation balance models (PBMs) are widely used to describe the dynamics of particulate systems. The simulation of PBMs becomes challenging with increasing numbers of dimensions and integral terms associated with phenomena, such as coalescence and breakage, which has motivated efforts to develop more computationally efficient numerical algorithms. This article presents high‐resolution finite‐volume methods for the parallel simulation of PBMs that scale well to ∼100 processors on a linux cluster. The high‐resolution methods provide second‐order accuracy with an accurate tracking of sharp fronts. The ParticleSolver software implementing these methods is verified by application to PBMs for (1) aerosol coagulation and condensation, (2) the formation of gold nanoparticles by nucleation, disproportionation, and coagulation, and (3) the nucleation and growth of inorganic crystals with a time‐varying shape distribution. © 2008 American Institute of Chemical Engineers AIChE J, 2008