bluuebunny/crossref_metadata_2025_split huggingface dataset:
Desde la Apertura del Silencio
Authors: Gallardo Rodrigo , Samaniego Mario 
Published: August 2012

Jaime León Ruiz -Tagle, pintor y dibujante. Nació en Santiago en 1951. Recibió el grado de Licenciado en Arte, con mención en Pintura en la Universidad de Chile. Además de su permanente actividad creadora ha sido Profesor de Dibujo y docente en el Programa de Magíster en Arte de la Universidad de Chile. Además se ha desempeñado como investigador del Departamento Técnico e Investigación DIT, de esa Casa de Estudios Superiores. Jaime León, en un trabajo de enorme persistencia a lo largo de casi treinta años, ha adoptado la figura humana como auténtico emblema temático y casi exclusivamente al dibujo como lenguaje plástico, privilegiando en esencia, los principios puristas del método académico del modelo vivo.
Toxic Chemical Information Sources
Authors: Callaghan Jessie , Dipper Jennifer 
Published: August 2012

Abstract
Knowing how to obtain relevant, up‐to‐date information about the health effects of a chemical is essential for the effective protection of workers and the environment. The way we access information is changing every day and the amount of occupational health and safety information available is forever expanding. Finding information to meet legislative and regulatory requirements, to write a Material Safety Data Sheet (MSDS) or Safety Data Sheet (SDS), to respond to an emergency, to determine the cause of an illness, or to develop a health and safety program can be challenging, overwhelming, and time consuming. Toxicological information and data are of interest to more than workers, toxicologists, industrial hygienists, lawyers, and regulators. The general public is increasingly interested in the health effects of industrial chemicals.
Correspondingly, there are many different types of information available to accommodate these diverse needs. Who is doing the research and how the information is going to be used will affect the amount of detail required. For some, knowing that the basic health effects of a particular chemical are respiratory or skin irritation is enough. For others, knowing the quality of the original study or report used to arrive at these conclusions will also be required. For still others, the information will be needed for an emergency so that whatever information is obtained must be gained quickly and be as accurate as possible.
This chapter discusses how to locate different types of information on the toxic effects of chemicals, starting with a discussion on how and where to search for information. It will then identify a number of valuable resources that contain specific types of information (e.g., comprehensive reviews, data banks, and fact sheets).
Talc
Authors: D. Rosenman Kenneth 
Published: August 2012

AbstractTalc is a natural mineral of the general chemical composition Mg3Si4O10(OH)2. The composition varies widely from one geological deposit to another and even within the same deposit. The main component, crystalline hydrated silicate of magnesium, is usually found as plates but rarely may also be found as fibers. In many talc deposits, other silicates such as the amphiboles, tremolite, and anthophyllite, as well as serpentines, antigorite, lizardite, and even chrysotile, may be present. This chapter discusses the health effects associated with talc without asbestos contaminants. Asbestos contaminants are to be distinguished from an asbestiform of talc that is covered in this chapter. However, a number of studies have been conducted to determine the health effects of talc in which the purity of the material was not known.
Microbial Bioaerosols in the Occupational Environment: Exposure, Detection, and Disease
Authors: Reponen Tiina , Green Brett James 
Published: August 2012

AbstractIn this chapter, sources and characteristics of airborne microbiological contaminants, including bacteria, viruses, and fungi, are discussed in relation to their detection and health effects associated with personal exposure in the occupational environment. The impacts of microorganisms including protists and protozoans and other botanically sourced bioaerosols such as pollen are not reviewed in this chapter. The potential exposures to microbial bioaerosols and the aerodynamic behavior of these contaminants are reviewed as well as their respiratory and dermal health effects. Direct and indirect sampling methods are presented along with methods of analysis. Methods to prevent personal exposure are also provided.
Polyvinyl Acetate, Alcohol and Derivatives, Polystyrene, and Acrylics
Authors: Walker Bailus , Stokes Lynette D. 
Published: August 2012

AbstractThe chlorofluorocarbons (CFCs) are used as refrigerants and because of their low chemical reactivity, they typically have long atmospheric residence times, and as a consequence, they are distributed globally. The widespread use of these chemicals cause depletion in ozone layer. Most of the nations of the world drafted and signed an agreement calling for the phaseout of CFCs. Further developments were initiated on two types of “in‐kind” replacements. The first were the hydrochlorofluorocarbons (HCFCs) and the second were the hydrofluorocarbons (HFCs). These chemicals and their replacements effect the environment enormously and are treated as greenhouse warming gases. It has been found that many of these chemicals are not highly toxic. The most typical response observed following overexposure is CNS depression related to the anesthetic properties of many of these chemicals. The study has been designed to allow for the determination of a no‐observed‐effect level (NOEL), a threshold, and the EC50as median effect concentration. The present chapter summarizes the properties, production, uses, toxic effects, environmental impact and guidelines of exposure of these chemicals.
From Reactive Chemicals Control to Comprehensive Chemicals Policy: An Evolution and Opportunity
Authors: Tickner Joel A. 
Published: August 2012

AbstractThe present chapter provides an overview for the improvements in chemical information, assessment, and management and emphasizes the need of comprehensive chemicals policy that leads to more sustainable chemicals, materials, and products. For many years, there has been widespread public concern about human exposure to toxic substances and the lack of information on how chemicals are used and how these exposures might affect health. It has been realized that the amount of exposure is not the only factor that produces risks but also the timing of the dose, particularly during critical windows of developmental vulnerability. During the past two decades, governments, companies, and nongovernmental organizations (NGOs) have identified significant limitations in existing structures for chemicals assessment and management. Many large users and producers of chemicals are now interested in developing sustainability policies that call for safer chemicals and products. The field of green chemistry and prevention through design (PtD) are contributing significantly in developing more sustainable chemicals management policies. There is a need for new chemical assessment and evaluation approaches that advance the development and adoption of safer alternatives and that do not shift risks to workers.
Influence of Powder Size on Production Parameters and Properties of Syntactic Invar Foams Produced by Means of Metal Powder Injection Moulding
Authors: Weise Jörg , Salk Natalie , Jehring Ulrike , Baumeister Joachim , Lehmhus Dirk , Bayoumi Mohamed A. 
Published: August 2012

AbstractThe sintering behavior and the mechanical properties of syntactic foams produced by means of metal‐powder injection moulding depend on the interaction of the metal matrix and the integrated hollow spheres. In order to investigate these mechanisms, Ni‐powder size was varied in the production of FeNi36‐syntactic foams with integrated hollow micro glass spheres. For mechanical characterization tensile tests and RFDA‐measurements were performed as the respective parameters were expected to react most sensitively upon variations of the foam structure.
Tensile properties and weibull modulus of some high‐performance polymeric fibers
Authors: Naito Kimiyoshi 
Published: August 2012

AbstractThe tensile properties and fracture behavior of poly‐(para‐phenylene‐2,6‐benzobisoxazole), poly‐(para‐phenylene terephthalamide), co‐poly‐(para‐phenylene‐3,4′‐oxydiphenylene terephthalamide), polyarylate, polyethylene, and poly(lactic acid) high‐performance polymeric fibers have been investigated. The Weibull statistical distributions of the tensile strength were also characterized. The results clearly show that for various types of high‐performance polymer fibers, the Weibull modulus decreases with an increase in the tensile modulus, the tensile strength, and inverse of the failure strain. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Octupolar Derivatives Functionalized with Superacceptor Peripheral Groups: Synthesis and Evaluation of the Electron‐Withdrawing Ability of Potent Unusual Groups
Authors: Rouxel Cédric , Le Droumaguet Céline , Macé Yohan , Clift Sophie , Mongin Olivier , Magnier Emmanuel , Blanchard‐Desce Mireille 
Published: August 2012

AbstractNovel tripodal derivatives with a triphenylamine core and that bear “superacidifiers” (i.e., fluorinated sulfoximinyl blocks) or novel sulfiliminyl moieties as peripheral groups were synthesized. These new chromophores show strong absorption in the near‐UV region and emission in the visible region. The fluorinated sulfoximinyl moieties were found to behave as potent auxochromic and electron‐withdrawing (EW) groups, thus leading to redshifted absorption and emission. These moieties promote a core‐to‐periphery intramolecular charge transfer (ctp‐ICT) transition, the energy of which was found to be correlated to their EW strength. In this study, we provide evidence of a linear correlation between the Hammett constant (σp) values and the electronic gap between the ground and first excited state of the three‐branched derivatives. This in turn was used to derive σp values of fluorinated sulfoximinyl moieties. These EWGs show unprecedentedly high σp values, up to 1.45 relative to 0.8 for NO2. Also, by using this method, the sulfiliminyl moiety was shown to exhibit similar EW strength as NO2, while promoting improved transparency and solubility. Finally, the superior EW strength of the fluorinated sulfoximine peripheral moieties was shown to induce significant enhancement of the two‐photon absorption responses in the red near‐IR region of the three‐branched derivatives relative to similar octupoles that bear more usual strong EW groups. These characteristics (improved nonlinear responses or transparency) open new routes for the design of nonlinear optical (NLO) chromophores for optical limiting or electro‐optical modulation. Such building blocks could also be of interest for optoelectronic applications, including the development of solar cells.
A Small‐Molecule Two‐Photon Probe for Nitric Oxide in Living Tissues
Authors: Seo Eun Won , Han Ji Hee , Heo Cheol Ho , Shin Jae Ho , Kim Hwan Myung , Cho Bong Rae 
Published: August 2012

AbstractTwo‐photon microscopy (TPM) has become an indispensable tool in the study of biology and medicine due to the capability of this method for molecular imaging deep inside intact tissues. For the maximum utilization of TPM, a variety of two‐photon (TP) probes for specific applications are needed. In this article, we report a small‐molecule TP probe (ANO1) for nitric oxide (NO) that shows a rapid and specific NO response, a 68‐fold fluorescence enhancement in response to NO, and a maximum TP‐action cross‐section of 170 GM (GM: 10−50 cm4 photon−1) upon reaction with excess NO. This probe can be easily loaded into cells and tissues and can real‐time monitor NO in living tissues at 100–180 μm depth for longer than 1200 s through the use of TPM, with minimum interference from other biologically relevant species.
Schiff Base Structured Acid–Base Cooperative Dual Sites in an Ionic Solid Catalyst Lead to Efficient Heterogeneous Knoevenagel Condensations
Authors: Zhang Mingjue , Zhao Pingping , Leng Yan , Chen Guojian , Wang Jun , Huang Jun 
Published: August 2012

AbstractAn acid–base bifunctional ionic solid catalyst [PySaIm]3PW was synthesized by the anion exchange of the ionic‐liquid (IL) precursor 1‐(2‐salicylaldimine)pyridinium bromide ([PySaIm]Br) with the Keggin‐structured sodium phosphotungstate (Na3PW). The catalyst was characterized by FTIR, UV/Vis, XRD, SEM, Brunauer–Emmett–Teller (BET) theory, thermogravimetric analysis, 1H NMR spectroscopy, ESI‐MS, elemental analysis, and melting points. Together with various counterparts, [PySaIm]3PW was evaluated in Knoevenagel condensation under solvent and solvent‐free conditions. The Schiff base structure attached to the IL cation of [PySaIm]3PW involves acidic salicyl hydroxyl and basic imine, and provides a controlled nearby position for the acid–base dual sites. The high melting and insoluble properties of [PySaIm]3PW are relative to the large volume and high valence of PW anions, as well as the intermolecular hydrogen‐bonding networks among inorganic anions and IL cations. The ionic solid catalyst [PySaIm]3PW leads to heterogeneous Knoevenagel condensations. In solvent‐free condensation of benzaldehyde with ethyl cyanoacetate, it exhibits a conversion of 95.8 % and a selectivity of 100 %; the conversion is even much higher than that (78.2 %) with ethanol as a solvent. The solid catalyst has a convenient recoverability with only a slight decrease in conversion following subsequent recyclings. Furthermore, the new catalyst is highly applicable to many substrates of aromatic aldehydes with activated methylene compounds. On the basis of the characterization and reaction results, a unique acid–base cooperative mechanism within a Schiff base structure is proposed and discussed, which thoroughly explains not only the highly efficient catalytic performance of [PySaIm]3PW, but also the lower activities of various control catalysts.
Should We Consider Heart Rate Reduction in Cardiac Transplant Recipients?
Authors: Sekar Baskar , Critchley William R. , Williams Simon G. , Shaw Steven M. 
Published: August 2012

AbstractIncreased resting heart rate is an independent modifiable risk factor for the development of cardiovascular disease. Numerous studies have demonstrated improved clinical outcomes with heart rate reduction in patients with coronary artery disease and heart failure, but its role in transplanted hearts is not yet established. Sinus tachycardia is more common in heart transplant recipients due to graft denervation. Although a large number of studies have recognized increased heart rate as a predictor of native coronary artery atherosclerosis and overall cardiac mortality, contradicting results have been observed in heart transplant recipients. There is no clear consensus about what the normal range of heart rate should be following heart transplantation. The aim of this article was to review the literature to evaluate whether heart rate reduction should be considered in heart transplant recipients.Dr. Simon G. Williams and Dr. Steven M. Shaw have received honoraria from Servier for advisory work.The authors have no other funding, financial relationships, or conflicts of interest to disclose.
ZK‐5: A CO2‐Selective Zeolite with High Working Capacity at Ambient Temperature and Pressure
Authors: Liu Qingling , Pham Trong , Porosoff Marc D. , Lobo Raul F. 
Published: August 2012

AbstractThe increased carbon dioxide concentration in the atmosphere caused by combustion of fossil fuels has been a leading contributor to global climate change. The adsorption‐driven pressure or vacuum swing (PSA/VSA) processes are promising as affordable means for the capture and separation of CO2. Herein, an 8‐membered‐ring zeolite ZK‐5 (Framework Type Code: KFI) exchanged with different cations (H+, Li+, Na+, K+, Mg2+, Ca2+) was synthesized as novel CO2 adsorbent. The samples were characterized by SEM, energy‐dispersive X‐ray spectroscopy (EDAX), XRD, and gas adsorption (CO2 and N2). The Toth adsorption model was used to describe the CO2 adsorption isotherms, and the isosteric heats of adsorption were calculated. CO2 capture adsorbent evaluation criteria such as working capacity, regenerability and CO2/N2 selectivity were applied to evaluate the zeolite adsorbents for PSA/VSA applications. The in situ FTIR CO2 adsorption spectra show that physisorption accounts for the largest fraction of the total CO2 adsorbed. The CO2 adsorption analysis shows that Mg‐ZK‐5 is the most promising adsorbent for PSA applications with the highest working capacity (ΔN=2.05 mmol g−1), excellent selectivity (α=121), and low isosteric heat. Li‐, Na‐ and K‐ZK‐5 with good working capacity (ΔN=1.55–2.16 mmol g−1) and excellent selectivity (α=103–128) are promising CO2 adsorbents for the VSA working region.
Differential regulation of axonal growth and neuromuscular junction assembly by HGF/c‐Met signaling
Authors: Li Pan P. , Madhavan Raghavan , Peng H. Benjamin 
Published: August 2012

AbstractBackground: During vertebrate neuromuscular junction (NMJ) development, contact between motor axons and muscle fibers is followed by pre‐ and post‐synaptic specialization. Using Xenopus nerve‐muscle cocultures, we recently showed that spinal neurons initially contacted muscle cells by means of filopodial processes, and that muscle‐derived basic fibroblast growth factor induced axonal filopodia and slowed axonal advance to promote nerve‐muscle interaction and NMJ establishment. In contrast, neurotrophins enhanced axonal growth but suppressed the extension of axonal filopodia and blocked NMJ formation. Results: Here we report that hepatocyte growth factor (HGF), which also supports motor neuron survival, was expressed by Xenopus muscle cells, and that forced expression of HGF in Xenopus spinal neurons inhibited the extension of axonal filopodia. Overexpression of the HGF‐receptor c‐Met in neurons also blocked the formation of axonal filopodia and furthermore sped up axonal growth, but a kinase‐dead form of c‐Met was unable to effect these changes. Importantly, treatment of nerve‐muscle cocultures with recombinant HGF or the expression of HGF or active c‐Met in neurons, or that of excess HGF in muscle, inhibited nerve‐induced AChR clustering in muscle. Conclusions: Our results suggest that HGF/c‐Met signaling in neurons promotes axonal growth but suppresses filopodial assembly in neurons and hinders NMJ establishment. Developmental Dynamics 241:1562–1574, 2012. © 2012 Wiley Periodicals, Inc.
PtIIand PdIIComplexes with atrans‐Chelating Bis(pyridyl) Ligand
Authors: Wang Nan , McCormick Theresa M. , Ko Soo‐Byung , Wang Suning 
Published: August 2012

AbstractAn atropisomeric bis(pyridyl) chelate ligand bis{3,3′‐[N‐Ph‐2‐(2′‐py) indolyl]} (bpib) has been found to readily formtrans‐chelating PdIIand PtIIcomplexes. Two such complexes, Pt(bpib)Cl2and Pd(bpib)Cl2have been isolated and their structures were determined by single‐crystal X‐ray diffraction analysis. Both Pt(bpib)Cl2and Pd(bpib)Cl2have a chiral structure withC2symmetry. Pt(bpib)Cl2displays a long‐lived phosphorescence withλem= 595 nm in a frozen CH2Cl2solution at 77 K. To examine the potential use of thetranschelate bpib ligand in oxidative coupling reactions catalysed by PdIIcompounds, acetoxylation of benzene, chlorobenzene and toluene by PhI(OAc)2using Pd(OAc)2/bpib (2:1) as the catalyst was examined and compared with thecis‐chelating system Pd(OAc)2/2,2′‐bipyridine (bipy). The bpib system was found to accelerate the reaction but lower the overall yield.
Synthesis, Characterization, and Catalytic Properties of Two Zwitterionic Hybrid SBA‐15 Mesoporous Silicas
Authors: Yang Miao , Xu Feifei , Wang Chang , Liu Xiumei , Yan Peifang , Li Peipei , Welz‐Biermann Urs 
Published: August 2012

AbstractZwitterionic hybrid SBA‐15 mesoporous silica materials containing both amine and sulfonic acid groups have been synthesized through cocondensation from as‐synthesized zwitterionic siloxane precursors (ZS) with tetraethoxysilane (TEOS). Characterization by XRD, TEM, and N2 adsorption–desorption measurements show that the as‐synthesized materials have ordered mesostructures. Analysis with UV, 29Si/13C cross‐polarization magic angle spinning (CP‐MAS) NMR, and X‐ray photelectron spectroscopy (XPS) and elemental analysis demonstrates that the zwitterionic parts have been successfully introduced into the silica framework, and the organic contents of 15 % hybrid samples are over 1.0 mmol/g. The presence of a secondary organoamine group enables the hybrid material to be further alkalized to achieve the desired basic properties. The materials were used as catalysts for the aldol condensation of acetone with 4‐nitrobenzaldehyde. With a good catalytic performance, the catalyst could be easily separated, recycled, and reactivated by secondary basification.
A Highly Sensitive Amperometric Immunosensor for Clenbuterol Detection in Livestock Urine
Authors: Li Shengxi , Zhang Jiong , Deng Wangping , Shen Xizhong , Song Shiping , Fan Chunhai 
Published: August 2012

AbstractWe report a highly sensitive competitive‐type assay for multiplexing electrochemical detection of clenbuterol in pig urine using a 16‐sensor array. In this design, the clenbuterol was first conjugated with bovine serum albumin (BSA), and then the conjugates were immobilized on the electrode surface to compete with the free clenbuterol in the sample for specific antibody. Under the optimal conditions, the reproducibility of the clenbuterol electrochemical immunosensor was evaluated to be 3.4 % (coefficient of variation, CV) and the limit of detection was estimated to be 1.3 pg/mL. The very low detection limit was probably derived from the higher efficiency of the competitive immunoreaction caused by appropriate quantities of the clenbuterol immobilized on the 16‐sensor array and the suitable amount of anti‐clenbuterol antibody in the assay system.
Imidazolium‐Functionalized SiO2 Nanoparticle Doped Proton Conducting Membranes for Anhydrous Proton Exchange Membrane Applications
Authors: Lin B. , Qiu B. , Qiu L. , Si Z. , Chu F. , Chen X. , Yan F. 
Published: August 2012

AbstractImidazolium surface functionalized SiO2 (Im‐SiO2) nanoparticle doped proton conducting membranes were prepared for anhydrous proton exchange membrane applications. The hybrid membranes were synthesized via in situ cross‐linking of a mixture containing polymerizable oil (styrene, acrylonitrile, and divinylbenzene), protic ionic liquids (PILs), and 1‐methyl‐3‐[(triethoxysilyl)propyl] imidazolium chloride surface functionalized silica nanoparticles. The resultant hybrid membranes show proton conductivity up to the order of 10–2 S cm–1 at 160 °C, which is higher that of the plain membrane (10–3 S cm–1 at 160 °C). In addition, incorporation of Im‐SiO2 nanoparticles could effectively prevent the release of PIL component from the composite membranes.
Hypopharyngeal paraganglioma: Case report and review of the literature
Authors: Mehta Vikas , Fischer Tova , Levi Gabe , Wang Beverly , Urken Mark L. 
Published: August 2012

AbstractBackgroundParagangliomas are rare, vascular, and predominantly benign neoplasms of neural crest origin. They typically arise in the head and neck from the carotid body, jugulotympanic, or vagal paraganglia. Rarely, paragangliomas occur in the larynx. Only 2 cases of hypopharyngeal paraganglioma have been reported. We discuss the case of a hypopharyngeal paraganglioma and review the literature concerning laryngopharyngeal paragangliomas.Methods and ResultsWe present the case of a woman with 2 months of dysphagia and hoarseness that was found to have a hypopharyngeal paraganglioma. The patient underwent embolization and resection of the mass via a lateral thyrotomy approach. Pathologic analysis and selective staining confirmed the presence of a paraganglioma.ConclusionsProper histopathologic identification of these tumors is tantamount to guiding treatment. The preferred operative approach is a lateral thyrotomy to minimize patient morbidity. We present the third documented case of a hypopharyngeal paraganglioma and the first in the English‐language literature. © 2012 Wiley Periodicals, Inc. Head Neck, 2013