bluuebunny/crossref_metadata_2025_split huggingface dataset:
Subchronic organismal toxicity, cytotoxicity, genotoxicity, and feeding response of pacific oyster (Crassostrea gigas) to lindane (γ-HCH) exposure under experimental conditions
Authors: Anguiano Gerardo , Llera-Herrera Raul , Rojas Emilio , Vazquez-Boucard Celia 
Published: September 2007

Abstract
This study evaluated organismal toxicity, cytotoxicity, and genotoxicity and the filtration rate in response to different concentrations of subchronic lindane (gamma-hexachlorocyclohexane [γ-HCH]), exposure (12 d) in adult Pacific oysters Crassostrea gigas. Oysters were exposed in vivo in laboratory aquaria to 10 different concentrations (0.0–10.0 mg/L) of γ-HCH. The median lethal concentration (LC50) after 12 d was calculated as 2.22 mg/L. Cytotoxic effects were observed in hemocytes, where the mean cell viability was significantly decreased at 1.0 mg/L of γ-HCH after 12 d. Genotoxicity of γ-HCH measured by single cell gel electrophoresis assay, in hemocytes was evident at 0.7 mg/L of γ-HCH after 12 d. After 4 h of exposure to γ-HCH, filtration rates were reduced compared with controls to 65.8 and 38.2% at concentrations of 0.3 and 0.7 mg/L, respectively, and after 11 d of exposure, filtration rates were reduced to 60.4 and 30.9% at concentrations of 0.1 mg/L and higher. These results show the subchronic effects of γ-HCH at different concentrations and effect sensitivities are categorized as filtration rate &lt; genotoxicity &lt; cytotoxicity &lt; mortality. The relevance of integral toxicity evaluation, considering different endpoints from molecular, cellular, and individual levels is discussed.
Acute and chronic toxicity of technical-grade pesticides to glochidia and juveniles of freshwater mussels (unionidae)
Authors: Bringolf Robert B. , Cope W. Gregory , Eads Chris B. , Lazaro Peter R. , Barnhart M. Christopher , Shea Damian 
Published: September 2007

Abstract
Chemical contaminants are among many potential factors involved in the decline of freshwater mussel populations in North America, and the effects of pesticides on early life stages of unionid mussels are largely unknown. The objective of this study was to determine the toxicity of technical-grade current-use pesticides to glochidia and juvenile life stages of freshwater mussels. We performed acute toxicity tests with glochidia (five species) and juveniles (two species) exposed to a suite of current-use pesticides including herbicides (atrazine and pendimethalin), insecticides (fipronil and permethrin), and a reference toxicant (NaCl). Because of limited availability of test organisms, not all species were tested with all pesticides. Toxicity tests with fungicides (chlorothalonil, propiconazole, and pyraclostrobin) were performed with one species (Lampsilis siliquoidea). Lampsilis siliquoidea glochidia and juveniles were highly sensitive to the fungicides tested but the technical-grade herbicides and insecticides, at concentrations approaching water solubility, were not acutely toxic to this or the other unionid species. In a 21-d chronic test with four-month-old juvenile L. siliquoidea, the 21-d median effective concentration (EC50) with atrazine was 4.3 mg/L and in atrazine treatments ≥3.8 mg/L mussel growth was significantly less than controls. The relatively high sensitivity of L. siliquoidea to chlorothalonil, propiconazole, and pyraclostrobin is similar to that reported for other aquatic organisms commonly used for toxicity testing. The relative risk associated with acute exposure of early life stages of mussels to technical-grade atrazine, pendimethalin, fipronil, and permethrin is likely low; however, survival and growth results with juvenile L. siliquoidea indicate that chronic exposure to high concentrations (≥3.8 mg/L) of atrazine may have the potential to impact mussel populations and warrants further investigation.
Evaluation of laboratory assays for the assessment of leaching of copper and chromium from ground-contact wood
Authors: García-Valcárcel Ana I. , Tadeo José L. 
Published: September 2007

AbstractLaboratory studies were conducted to assess the leaching of Cu and Cr from wood, treated with a Cu-Cr-B preservative, when placed in contact with soil. Two laboratory assays were performed: Wood in contact with soil solutions over 30 d, and wood in direct contact with soil over 30 weeks. The influence of several factors, such as soil type and fertilizer use, was studied in both assays. In addition, the effect of soil moisture content and temperature was evaluated when wood was in contact with soil. A discrepancy in the results of the laboratory assays was observed. Leaching of Cu and Cr increased when soil in contact with wood was fertilized, but only an increase of Cu leaching was observed when soil solutions from fertilized soils were used. Moreover, soil solutions from a sandy clay loam soil produced a higher Cu leaching than those from a loamy sand soil, whereas the contrary occurred when treated wood was in direct contact with these soils. In the assay of treated wood in ground contact, the highest metal losses were produced in fertilized soils maintained at constant temperature and high soil moisture content, the latter being the most important factor. These losses were in the range of 5.34 to 15.6% for Cu and 1.85 to 2.35% for Cr in the soils studied. The proposed laboratory assay, using treated wood in direct contact with soil at a moisture content near field capacity during a period of 30 weeks, produced total metal losses that were in accordance with those reported by other authors under field conditions, expressed on a per-year basis.
Colorants for Foods
Authors: Marmion Daniel ,   Updated by Staff
Published: September 2007

AbstractThis article includes a brief history of the use of colorants in foods and the development of legislation in the United States to control them. It describes where and why colorants are used, lists all those currently in use, identifies each as either needing certification or not, and describes the chemical and physical properties, method of manufacture, chemical structure, chemical classification, and uses of each. Individual and general restrictions relating to the use of colorants are described, and sample specifications are shown. Includes references and sources for more information regarding colorants including their analysis as is and in product matrices.
Milk and Milk Products
Authors: Hall Carl W. ,   Updated by Staff
Published: September 2007

AbstractHall, Carl W. (Engineering Information Services). Milk from cows is a significant food source throughout the world. Milk provides food components to meet important nutritional needs of the human body. Vitamins, minerals, sugar, fat, and protein are contained in milk. The amount of these components in milk varies with the breed of animal, the particular animal, and with other species that produce milk. As a human food, care must be taken in the production and processing of milk and milk products to maintain quality. Contamination must be avoided. Appropriate temperature control must be provided to hold raw milk, process milk into beverage, process milk into its many products, and deliver quality products to the consumer. Changing consumer habits influence the kind and amount of products manufactured. Appropriate quality determinations and controls must be provided throughout the process to assure that safe, nutritious products are delivered to the consumer on an economical basis.
Nitriles
Authors: DeVito Stephen C. 
Published: September 2007

AbstractNitriles are cyano‐substituted organic compounds, ie, organic derivatives of hydrogen cyanide. The combination of unique physical properties imparted by the nitrile group and the ease with which nitrile groups can be converted to other functional groups has made organonitrile compounds commercially important substances. Organonitriles may be prepared by a variety of methods including metathesis of organohalides, ammoxidation of hydrocarbons, dehydration of amides, and addition of hydrogen cyanide to unsaturated organic compounds such as aldehydes, ketones, and olefins. Some of the more common transformations include hydrolysis or alcoholysis to produce amides, acids and esters, and hydrogenation to produce amines, which are intermediates for the production of polyurethanes and polyamides. Nitriles are generally toxic to the extent that they may be metabolized in the body to liberate cyanide, and care in the body to liberate cyanide and care should be taken to prevent skin contact, oral ingestion or inhalation of vapors. This article addresses the following organonitrile compounds in some detail: acetonitrile, adiponitrile, a‐aminonitriles, azobisnitriles, benzonitrile, cyanoacetic acid (and esters), isophthalonitrile, methylglutaronitrile, pentenenitriles, and fatty acid nitriles.
Aggressive Langerhans cell histiocytosis following T‐ALL: Clonally related neoplasms with persistent expression of constitutively active NOTCH1
Authors: Rodig Scott J. , Payne Ethan G. , Degar Barbara A. , Rollins Barrett , Feldman Andrew L. , Jaffe Elaine S. , Androkites Arlene , Silverman Lewis B. , Longtine Janina A. , Kutok Jeffery L. , Fleming Mark D. , Aster Jon C. 
Published: September 2007

AbstractLangerhans cell histiocytosis (LCH) and related entities are neoplasms of unknown pathogenesis. Here, we describe studies assessing the role of NOTCH1 mutations in LCH, which were based on a case of fatal Langerhans cell tumor after T‐cell acute lymphoblastic leukemia (T‐ALL). Although the two types of neoplasm in this patient were temporally and pathologically distinct, molecular analyses showed that they harbored the same T‐cell receptor gene rearrangements and two activating NOTCH1 mutations involving exons 27 and 34. The exon 27 mutation altered a conserved cysteine residue in the N‐terminal portion of the NOTCH1 heterodimerization domain, while the mutation in exon 34 introduced a premature stop codon that results in the deletion of C‐terminal negative regulatory PEST domain. Analysis of cDNA prepared from the aggressive Langerhans cell tumor showed that the NOTCH1 mutations were aligned in cis, a configuration that caused synergistic increases in NOTCH1 signal strength in reporter gene assays. Immunohistochemistry confirmed that the Langerhans cell tumor also expressed NOTCH1 protein. Although these data suggested that NOTCH1 mutations might contribute to the pathogenesis of typical sporadic LCH and related neoplasms occurring in the absence of T‐ALL, an analysis of 24 cases of LCH and Rosai–Dorfman Disease occurring in patients without an antecedent history of T‐ALL revealed no mutations. Thus, activating NOTCH1 mutations appear to be unique to aggressive Langerhans cell tumors occurring after T‐ALL. Persistent expression of NOTCH1 in such tumors suggests that Notch pathway inhibitors could have a role in the treatment of these unusual neoplasms. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
The prognostic significance of leukemic cells clearance kinetics evaluation during the initial course of induction therapy with HAD (homoharringtonine, cytosine arabinoside, daunorubicin) in patients with de novo acute myeloid leukemia
Authors: Xiao Zhijian , Xue Hua , Li Rui , Zhang Li , Yu Minghua , Hao Yushu 
Published: September 2007

AbstractThe impact of the percentage of residual leukemic cells (RLCs) at the end of first course of induction chemotherapy (T1) or during aplasia (T2) on complete remission (CR) rate, disease‐free survival (DFS), and overall survival (OS) were retrospectively analyzed in 72 cases of de novo acute myeloid leukemia (AML) treated with HAD (homoharringtonine, cytosine arabinoside, and daunorubicin) regimen. The patients were separated into two subgroups by a cutoff of 10% bone marrow leukemic cells at T1 or T2 time point. The CR rate, DFS, and OS were significantly different between the two groups. We further confirmed that the percentage of RLCs at T1 or T2 is an independent prognostic factor of AML. Am. J. Hematol., 2008. © 2007 Wiley‐Liss, Inc.
Morphology development for single‐site ethylene copolymers in rotational molding
Authors: Xu H. , Bellehumeur C. T. 
Published: September 2007

AbstractThe morphology development of ethylene copolymers was modeled with the modified phase‐field theory. The metastability of polymer crystallization was also considered in the modeling. Modeling and experimental work were simultaneously undertaken to compare the crystallization kinetics of single‐site‐catalyzed and Ziegler‐catalyzed resins and their influence on morphology development in the rotational‐molding process. With a more uniform short‐chain branch distribution, the single‐site copolymers developed well‐defined spherulitic structures. The Ziegler–Natta catalyst resins were characterized by a higher nuclei density and a faster crystallization rate and produced finer structures in the molded parts. The modeling approach proposed in our work allowed an evaluation of the processing and the material effects on the development of morphological features during melt solidification. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Reactivity and efficiency of difunctional radical photoinitiators
Authors: Dietlin C. , Lalevee J. , Allonas X. , Fouassier J. P. , Visconti M. , Bassi G. Li , Norcini G. 
Published: September 2007

AbstractThree difunctional cleavable photoinitiators based on the α‐hydroxyketone structure were tested in photopolymerization reactions with Fourier transform infrared spectroscopy. The excited‐state processes were investigated with time‐resolved laser absorption spectroscopy and laser‐induced photocalorimetry, which allowed the cleavage quantum yields to be determined and estimates of the triplet‐state lifetimes and interaction rate constants with a methacrylate monomer to be given. Modeling calculations helped to describe the ground‐state properties and showed that the difunctional photoinitiators exhibited different chromophoric groups than the corresponding monofunctional photoinitiator. An examination of the photochemical reactivity versus the practical efficiency observed in the polymerization showed that these difunctional photoinitiators exhibited better efficiency than the parent molecule, mainly because of their increased absorption properties. Their practical efficiency appeared to be better because of better light absorption when standard polychromatic light sources were used. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Viscoelasticity of epoxy resin/silica hybrid material prepared via sol–gel process: Considered in terms of morphology
Authors: Araki Wakako , Adachi Tadaharu 
Published: September 2007

AbstractWe investigated the relationship between the morphology and viscoelasticity of epoxy/silica hybrid materials manufactured via two different processes: simultaneous formation of epoxy and silica phases and sequential formation of silica phase in the prepared epoxy phase. The glass transition phenomena of the hybrid materials mostly depended on their silica structure. The particular structure did not affect Tg much, while the silica chain structure greatly raised Tg of the hybrid samples. The storage modulus E′ depended on the volume fraction of the silica phase ζ, rather than the silica structure. In the glassy state, E′ of the hybrid samples slightly decreased when compared with the neat epoxy samples. Lack of chemical reaction between the silica and the epoxy phases could be attributed to this decrease at which the silica structure could have worked as a flaw. In the rubbery state, E′ greatly increased with increasing silica content ζ regardless of the silica structure, and this behavior well agreed with that predicted by the Davies model, because the physical interaction worked very well in the rubbery region. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation and properties of glucosamine and carboxymethylchitin from shrimp shell
Authors: Santhosh Sethumadhavan , Mathew Paruthapara T. 
Published: September 2007

AbstractExport of processed and frozen shrimp products is the backbone of seafood industries. But, shrimp processing industries give rise to a large amount of waste materials. These waste products generate serious pollution hazards. A wise method to minimize environmental threats from prawn processing waste is to convert them in to useful products. Shrimp shell waste can be economically converted to chitin, a mucopolysaccharide. This marine polysaccharide and its derivatives hold a major part in our lives as medicines, cosmetics, textiles, paper, food and other branches of industry because of their unique nature in properties such as low toxicity, biocompatibility, hydrophobicity, etc. Hydrolysis of chitin yields a value added product, Glucosamine. Carboxymethylchitin is another derivative of chitin, prepared by the carboxymethylation reaction. This review article is an attempt to give an idea about the preparation, properties, and applications of the derivatives of chitin viz., glucosamine and carboxymethylchitin. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis of ethylene and norbornene copolymer with metallocene catalysts and characteristic analysis
Authors: Yao Zhen , Lv Fei , Liu Shao‐Jie , Cao Kun 
Published: September 2007

AbstractTo synthesis ethylene (E) and norbornene (NB) copolymer with high glass transition temperature and transparency, three metallocene catalysts with different symmetric structure were evaluated, respectively. The catalyst activity, NB fraction in copolymer and the transparency of copolymers produced under various conditions were investigated. It has been found that C2 symmetric catalyst such as rac‐[En(Ind)2]ZrCl2 was the best choice to produce copolymer with high NB fraction while keeping high catalyst activity. Furthermore, the effects of reaction conditions on activity of rac‐[En(Ind)2]ZrCl2 and the resultant copolymer structure have also been thoroughly studied. The results indicate that increasing the NB/E ratio is the effective way to increase NB content of copolymer when NB/E ratio is less than 20. However, when NB/E ratio is over 20, further increase in NB/E ratio will lead to significant lower catalyst activity and very limited increase in NB content of copolymer. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Novel nanoporous membranes from regenerated bacterial cellulose
Authors: Phisalaphong Muenduen , Suwanmajo Thapanar , Sangtherapitikul Preecha 
Published: September 2007

AbstractBacterial cellulose (BC) in an NaOH/urea aqueous solution was used as a substrate material for thefabrication of a novel regenerated cellulose membrane. The dissolution of BC involved swelling BC in a 4 wt % NaOH/3 wt % urea solution followed by a freeze–thaw process. The BC solution was cast onto a Teflon plate, coagulated in a 5 wt % CaCl2 aqueous solution, and then treated with a 1 wt % HCl solution. Supercritical carbon dioxide drying was then applied to the formation of a nanoporous structure. The physical properties and morphology of the regenerated bacterial cellulose (RBC) films were characterized. The tensile strength, elongation at break, and water absorption of the RBC membranes were 4.32 MPa, 35.20%, and 49.67%, respectively. The average pore size of the RBC membrane was 1.26 nm with a 17.57 m2/g surface area. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Effect of disinfection by microwave irradiation on the strength of intact and relined denture bases and the water sorption and solubility of denture base and reline materials
Authors: Seó Rosangela Seiko , Vergani Carlos Eduardo , Giampaolo Eunice Teresinha , Pavarina Ana Cláudia , Reis José Maurício dos Santos Nunes , Machado Ana Lucia 
Published: September 2007

AbstractThis study evaluated the influence of microwave disinfection on the strength of intact and relined denture bases. Water sorption and solubility were also evaluated. A heat‐polymerized acrylic resin (Lucitone 550) was used to construct 4‐mm‐thick (n = 40) and 2‐mm‐thick (n = 160) denture bases. Denture bases (2‐mm) were relined with an autopolymerizing resin (Tokuso Rebase Fast, Ufi Gel Hard, Kooliner, or New Truliner). Specimens were divided into four groups (n = 10): without treatment, one or seven cycles of microwave disinfection (650 W for 6 min), and water storage at 37°C for 7 days. Specimens were vertically loaded (5 mm/min) until failure. Disc‐shaped specimens (50 mm × 0.5 mm) were fabricated (n = 10) to evaluate water sorption and solubility. Data on maximum fracture load (N), deflection at fracture (mm), fracture energy (N mm), water sorption (%), and solubility (%) were analyzed by two‐way analysis of variance and Student–Newman–Keuls tests (α = 0.05). One cycle of microwave disinfection decreased the deflection at fracture and fracture energy of Tokuso Rebase Fast and New Truliner specimens. The strength of denture bases microwaved daily for 7 days was similar to the strength of those immersed in water for 7 days. Microwave disinfection increased the water sorption of all materials and affected the solubility of the reline materials. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Hierarchy crystallization structure of a polypropylene random copolymer injection‐molded bar induced by a nucleating agent
Authors: Wang Yong , Gao Yao , Shi Jing 
Published: September 2007

AbstractIn this work, the effect of a nucleating agent on the crystallization structure of an injection‐molded bar of a polypropylene random copolymer (PPR) with sorbitol derivatives [1,2,3,4‐dibenzylidene sorbitol (DBS)] has been studied. The results show that pure PPR forms a simple skin–core crystallization structure. However, PPR/DBS forms an interesting and complicated hierarchy crystallization structure: there is a transition layer between the skin layer and the core zone. In this transition layer, the crystallization structure consists of some perfect spherulites and many tiny crystallites. Further research suggests that the formation of the hierarchy crystallization structure depends on not only the content of the nucleating agent in the PPR matrix but also the mold temperature during the injection‐molding processing. The crystallization behavior of PPR/DBS during the cooling process has been characterized with polarization optical microscopy and differential scanning calorimetry. The results suggest that there are different mechanisms in the crystallization process of PPR/DBS. The formation of a three‐dimensional DBS network under a certain condition might be the main reason for the complicated hierarchy crystallization structure. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Importance of RNA‐protein interactions in bacterial ribonuclease P structure and catalysis
Authors: Smith J. Kristin , Hsieh John , Fierke Carol A. 
Published: September 2007

AbstractRibonuclease P (RNase P) is a ribonucleoprotein (RNP) complex that catalyzes the metal‐dependent maturation of the 5′ end of precursor tRNAs (pre‐tRNAs) in all organisms. RNase P is comprised of a catalytic RNA (P RNA), and at least one essential protein (P protein). Although P RNA is the catalytic subunit of the enzyme and is active in the absence of P protein under high salt concentrations in vitro, the protein is still required for enzyme activity in vivo. Therefore, the function of the P protein and how it interacts with both P RNA and pre‐tRNA have been the focus of much ongoing research. RNA‐protein interactions in RNase P serve a number of critical roles in the RNP including stabilizing the structure, and enhancing the affinity for substrates and metal ions. This review examines the role of RNA‐protein interactions in bacterial RNase P from both structural and mechanistic perspectives. © 2007 Wiley Periodicals, Inc. Biopolymers 87: 329–338, 2007.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com