bluuebunny/crossref_metadata_2025_split huggingface dataset:
A numerical model for predicting diffusivity in a biocatalyst particle with heterogeneous reactions
Authors: Wu Binxin , Liu Yan , Liao Wei , Chen Shulin 
Published: June 2008

AbstractDetermination of effective diffusivity of a substrate in biocatalyst particles is a key requirement in modeling heterogeneous reactions. The diffusivity is mainly controlled by the molecular‐diffusion characteristics of the substrate, the tortuousness of the diffusion path within the biocatalyst, and the void fraction of particle volume available for diffusion. A general numerical model describing reactions in a biocatalyst particle following zero‐order, first‐order, and Michaelis‐Menten kinetics was developed. Finite volume method was used to discretize the nonlinear second‐order differential equation, and tridiagonal matrix algorithm was applied to solve the algebraic equation iteratively after discretization. Computer codes were written for calculating the diffusivity under specified boundary conditions. The numerical solution of the diffusion‐reaction equations was validated against the experimental data from literatures. The model was further calibrated with experimental data obtained from fungal pellet experiments and then verified using additional data. The results show that the inverse methodology developed in this study was capable of predicting diffusivity in biocatalyst particles. Based on the predicted diffusivity, oxygen consumption by an individual pellet was simulated, oxygen consumptions by small versus large pellets were compared, and the effect of reaction rate on oxygen consumption was evaluated. © 2008 American Institute of Chemical Engineers AIChE J, 2008
A multivariate statistical process control procedure for BIAS identification in steady‐state processes
Authors: Sánchez Mabel C. , Alvarez Carlos R. , Brandolin Adriana 
Published: June 2008

AbstractIn this article, a multivariate statistical process control (MSPC) strategy, devoted to bias identification and estimation for processes operating under steady‐state conditions, is presented. The technique makes use of the D statistic to detect the presence of biases. Besides, it uses a new decomposition of this statistic to identify the faulty sensors. The strategy is based only on historical process data. Neither process modeling nor assumptions about the probability distribution of measurement errors are required. In contrast to methods based on fundamental models, both redundant and nonredundant measurements can be examined to identify the presence of biases. The performance of the proposed technique is evaluated using data‐reconciliation benchmarks. Results indicate that the technique succeeds in identifying single and multiple biases and fulfills three paramount issues to practical implementation in commercial software: robustness, uncertainty, and efficiency. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Continuous distribution kinetics for microwave‐assisted oxidative degradation of poly(alkyl methacrylates)
Authors: Marimuthu A. , Madras Giridhar 
Published: June 2008

AbstractThe microwave‐assisted oxidative degradation of poly(alkyl methacrylates) namely poly(methyl methacrylate), poly(ethyl methacrylate) (PEMA), and poly(butyl methacrylate) was investigated. The kinetic parameters were compared to that obtained by thermal oxidative degradation. The molecular weight distributions (MWDs) were simulated using continuous distribution kinetic models. The MWD of polymer was expressed as a γ‐distribution, and the mathematical solutions were developed in terms of γ‐distribution parameters. The MWD of degradation mixture approaches an exponential distribution under both oxidative thermal degradation and microwave‐assisted oxidative degradation of poly(alkyl methacrylates), indicating random chain scission. The degradation of PEMA was investigated in the presence of three different oxidizers. The hydrogen abstraction from polymer and the oxidative random chain scission of polymer radicals were found to be the important steps in the overall mechanism of microwave‐assisted oxidative degradation of poly(alkyl methacrylates). The model developed can be used to predict degradation rate of the polymer in the presence of any oxidizers by knowing only the dissociation rate constant of the oxidizer. © 2008 American Institute of Chemical Engineers AIChE J, 2008
Multilayered patella: Similar radiographic findings in pseudoachondroplasia and recessive multiple epiphyseal dysplasia
Authors: Vatanavicharn Nithiwat , Lachman Ralph S. , Rimoin David L. 
Published: June 2008

AbstractA multilayered patella is a characteristic radiographic finding of recessive multiple epiphyseal dysplasia (rMED) caused by DTDST mutations. However it has been recently reported in a dominant MED case with a COL9A2 mutation. We report on a new radiographic patellar finding in a patient with pseudoachondroplasia and a heterozygous COMP mutation. It is similar to the radiographic appearance of fusing multilayered patellae in rMED cases. This led us to search the International Skeletal Dysplasia Registry for similar abnormalities. We did not observe this finding in other skeletal dysplasias or other pseudoachondroplasia cases. However we found an accessory ossification center of the patella in another pseudoachondroplasia case. Thus, we hypothesize that variable defects of cartilage extracellular matrix can result in similar abnormal patellar ossifications, and emphasize the importance of a lateral knee radiograph in patients with the pseudoachondroplasia‐MED bone dysplasia group of disorders. © 2008 Wiley‐Liss, Inc.
Mucopolysaccharidoses in Brazil: What happens from birth to biochemical diagnosis?
Authors: Vieira Taiane , Schwartz Ida , Muñoz Verónica , Pinto Louise , Steiner Carlos , Ribeiro Márcia , Boy Raquel , Ferraz Victor , de Paula Ana , Kim Chong , Acosta Angelina , Giugliani Roberto 
Published: June 2008

AbstractMucopolysaccharidoses (MPS) form a group of inherited metabolic disorders characterized by intralysosomal storage of glycosaminoglycans. This study aimed to investigate the path followed by Brazilian patients from birth to diagnosis. An interview was conducted with patient's parents or guardians with subsequent review of patient's medical records. One hundred thirteen patients with MPS were included (MPS I: 18, MPS II: 43, MPS IIIA: 2, MPS IIIB: 3, MPS IIIC: 1, MPS IVA: 15, MPS IVB: 1, MPS VI: 29, MPS VII: 1) from 97 families. Median age at the onset of signs/symptoms was 18 months (MPS I: 18, MPS II: 24, MPS IVA: 8, MPS VI: 8). Skeletal abnormalities (for MPS IVA and MPS VI), joint contractures (for MPS II), and typical facial features (for MPS I) were the most frequently reported first signs/symptoms. Several health professionals were involved in patient's care as of the onset of symptoms until biochemical diagnosis was established. Median age at diagnosis was 76 months (MPS I: 75, MPS II: 95, MPS IVA: 75, MPS VI: 52). Considering the group as a whole, there was a 4.8‐year delay between the onset of signs/symptoms and the establishment of the diagnosis. Considering that specific therapies are available for some of these disorders and that early treatment is likely to change more favorably the natural history of the disease, efforts should be made to minimize this delay. We believe that this situation can be improved by measures that both increase awareness of health professionals about MPS and improve access to diagnostic tests. © 2008 Wiley‐Liss, Inc.
Long‐term follow‐up in Stuve–Wiedemann syndrome: A clinical report
Authors: Gaspar Isabel Mendes , Saldanha Tiago , Cabral Pedro , Vilhena M. Manuel , Tuna Madalena , Costa Cristina , Dagoneau Nathalie , Daire Valerie Cormier , Hennekam Raoul C.M. 
Published: June 2008

AbstractStuve–Wiedemann syndrome (SWS) is an autosomal recessively inherited disorder that is usually associated with high mortality in the neonatal period. Eleven cases have been published with prolonged survival, the oldest being 16 years. This phenotype is characterized by progressive skeletal anomalies including short stature, severe spinal deformities, bowing of the long bones, contractures and spontaneous fractures, and by neurological features that resemble dysautonomia. Here we report on the natural history of a Portuguese girl from birth till 12 years. The diagnosis was molecularly confirmed by the detection of a homozygous 4 bp deletion (167_170 del TAAC) in exon 3 of LIFR. We compare the findings in this patient to other patients with prolonged survival from the literature. © 2008 Wiley‐Liss, Inc.
Beckwith‐Wiedemann syndrome in adults: Observations from one family and recommendations for care
Authors: Greer Kimberly J. , Kirkpatrick Susan J. , Weksberg Rosanna , Pauli Richard M. 
Published: June 2008

AbstractLiterature review and clinical findings in four affected adult males from one family suggest that there are serious and currently ill‐defined health risks in adults with Beckwith‐Wiedemann syndrome (BWS). These may include male subfertility, vascular anomalies, renal abnormalities, hearing loss and, possibly, an increased risk for adult‐onset malignancy. Given present knowledge, recommendations in caring for adults with this disorder remain tentative but likely should include counseling for possible infertility in males, screening echocardiography, renal sonogram and renal function testing, and counseling about possible increased risk for adult onset malignancy. © 2008 Wiley‐Liss, Inc.
Mitochondrial DNA haplogroup analysis in patients with bipolar disorder
Authors: Kazuno An‐a , Munakata Kae , Mori Kanako , Nanko Shinichiro , Kunugi Hiroshi , Nakamura Kazuhiko , Mori Norio , Yamada Kazuo , Yoshikawa Takeo , Kato Nobumasa , Kato Tadafumi 
Published: June 2008

AbstractSeveral lines of evidence support mitochondrial dysfunction in bipolar disorder. Elevated calcium level in platelets is reported in this disease. To verify mitochondrial DNA (mtDNA) haplogroups characteristic to bipolar disorder, we sequenced mtDNA of seven regions and performed haplogroup analysis in 195 patients with bipolar disorder and 255 controls. They belonged to 16 major mtDNA haplogroups, A, B4, B5, C, D4, D5, F, G, M7, M8, M9, M10‐12, N9a, N9b, Y, and Z. The logistic regression analysis revealed that the haplogroup N9a was over‐represented in bipolar disorder. We also performed a case–control study for two functional mtDNA polymorphisms, mtDNA5460G > A and 12358A > G, that altered intracellular calcium dynamics. While the mtDNA5460G > A polymorphism was not associated with bipolar disorder, the mtDNA12358A > G polymorphism was associated with bipolar disorder in 199 patients with bipolar disorder and 260 controls. However, this association was not replicated in an independent sample set. Possible significances of these findings are discussed. © 2008 Wiley‐Liss, Inc.
Botulinum toxin type a induces direct analgesic effects in chronic neuropathic pain
Authors: Ranoux Danièle , Attal Nadine , Morain Francoise , Bouhassira D. 
Published: June 2008

AbstractObjectiveBotulinum toxin type A (BTX‐A) has been reported to have analgesic effects independent of its action on muscle tone, possibly by acting on neurogenic inflammation. Such a mechanism may be involved in peripheral neuropathic pain.MethodsA possible direct analgesic effect of BTX‐A pain processing was investigated in 29 patients with focal painful neuropathies and mechanical allodynia using a randomized, double‐blind, placebo‐controlled design. Patients received a one‐time intradermal administration of BTX‐A (20–190 units) into the painful area. Outcome measures, evaluated at baseline, then at 4, 12, and 24 weeks, included average spontaneous pain intensity, quantified testing of thermal and mechanical perception and pain, allodynia to brushing (area, intensity), neuropathic symptoms, clinical global impression, and quality of life.ResultsBTX‐A treatment, relative to placebo, was associated with persistent effects on spontaneous pain intensity from 2 weeks after the injection to 14 weeks. These effects correlated with the preservation of thermal sensation at baseline (p < 0.05). BTX also improved allodynia to brush and decreased pain thresholds to cold, without affecting perception thresholds. There were sustained improvements in the proportion of responders (number needed to treat for 50% pain relief: 3.03 at 12 weeks), neuropathic symptoms, and general activity. Most patients reported pain during the injections, but there were no further local or systemic side effects.InterpretationThese results indicate for the first time that BTX‐A may induce direct analgesic effects in patients with chronic neuropathic pain independent of its effects on muscle tone and suggest novel indications for BTX‐A in analgesia. Ann Neurol 2008
Effect of poly(styrene‐co‐maleic anhydride) imidization on the miscibility and phase‐separation temperatures of poly(styrene‐co‐maleic anhydride)/poly(vinyl methyl ether) and poly(styrene‐co‐maleic anhydride)/ poly(methyl methacrylate) blends
Authors: Fang Haixia , Mighri Frej , Ajji Abdellah 
Published: June 2008

AbstractThe objective of this work was to study the miscibility and phase‐separation temperatures of poly(styrene‐co‐maleic anhydride) (SMA)/poly(vinyl methyl ether) (PVME) and SMA/poly(methyl methacrylate) (PMMA) blends with differential scanning calorimetry and small‐angle light scattering techniques. We focused on the effect of SMA partial imidization with aniline on the miscibility and phase‐separation temperatures of these blends. The SMA imidization reaction led to a partially imidized styrene N‐phenyl succinimide copolymer (SMI) with a degree of conversion of 49% and a decomposition temperature higher than that of SMA by about 20°C. We observed that both SMI/PVME and SMI/PMMA blends had lower critical solution temperature behavior. The imidization of SMA increased the phase‐separation temperature of the SMA/PVME blend and decreased that of the SMA/PMMA blend. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Modeling of ethylene polymerization with difunctional initiators in tubular reactors
Authors: Khazraei P. K. F. , Dhib R. 
Published: June 2008

AbstractThe severe thermodynamic conditions of the high‐pressure ethylene polymerization process hinder ethylene from going to full conversion. One remedy to improve the monomer conversion is to make effective use of difunctional peroxides. Multifunctional peroxides can accelerate the polymerization rate, produce branching, and modify the rheological properties of molten polymers. This article proposes a kinetic model based on a postulated reaction mechanism for ethylene polymerization initiated by difunctional initiators in a high‐pressure tubular reactor. Three peroxides suitable for ethylene polymerization were compared for their effectiveness. Compared to dioctanoyl peroxide, the two difunctional peroxides considered performed much better for the higher temperature regions of the reactor and gave ethylene conversions nearly twice as high for only half of the initial amount of dioctanoyl. They also generated low‐density polyethylene polymer with a broader molecular weight distribution and longer chain branching. These two important polymer characteristics can influence the end‐product rheological properties. Injecting fresh ethylene at different points along the reactor improved the conversion and produced more branched polymer. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Bamboo is a suitable template for polymerizations
Authors: Eastman Scott A. , Lesser Alan J. , McCarthy Thomas J. 
Published: June 2008

AbstractIn situ hydrosilation reactions and ring‐opening metathesis polymerizations were demonstrated to occur in bulk samples of bamboo. Bamboo was infused with silicone precursors or cyclodiene monomers with the assistance of supercritical CO2 and subsequently crosslinked or polymerized, respectively. Bending stiffness, energy release rate, and specific fire resistance properties of the bamboo‐polymer composites were measured and compared with unmodified bamboo. Bamboo‐silicone composites showed an increase in fire resistance and a slight increase in mechanical properties. The bamboo‐poly(alkenamer) composites showed significant increases in mechanical properties. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Microstructural parameters in electron‐irradiated hydroxypropyl methylcellulose films using X‐ray line profile analysis
Authors: Sangappa  , Demappa T. , Mahadevaiah  , Ganesh S. , Divakara S. , Somashekar R. 
Published: June 2008

AbstractThe changes in microstructural parameters in hydroxypropyl methylcellulose (HPMC) polymer films irradiated with 8 MeV electron beam have been studied using wide‐angle X‐ray scattering (WAXS) method. The crystal imperfection parameters such as crystal size <N>, lattice strain (g in %), and enthalpy (α*) have been determined by line profile analysis (LPA) using Fourier method of Warren. Exponential, Lognormal, and Reinhold functions for the column length distributions have been used for the determination of these parameters. The goodness of the fit and the consistency of these results suggest that the exponential distribution gives much better results, even though lognormal distribution has been widely used to estimate the similar stacking faults in metal oxide compounds. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Determination of Mark–Houwink parameters of ethylene–norbornene copolymers and molecular characteristics estimation
Authors: Yao Zhen , Liu Shao‐jie , Lv Fei , Cao Kun 
Published: June 2008

AbstractEthylene–norbornene copolymers (ENC) with ∼ 50%, ∼ 25% and ∼ 15% norbornene (NB) fraction in a wide range of molecular weight were produced by metallocene catalysts. By coupling the gel permeation chromatography (GPC) with the intrinsic viscosity data in 1,2,4‐trichlorobenzene (TCB)at 150°C, the Mark–Houwink parameters of ENC were determined and compared with previous classical analysis using polyethylene's relative parameters. The results indicated that parameter K was considerably increased with decreasing NB fraction in ENC but parameter α was only increased slightly. Furthermore, the structure characteristics and correlative rheological parameters of resultant ENC were also calculated and discussed by the Stockmayer–Fixman analysis. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and characterization of poly(methyl methacrylate) polymerized by microwave energy or conventional water bath
Authors: Acosta‐Torres L. S. , Barceló‐Santana F. H. , Álvarez‐Gayosso C. A. , Reyes‐Gasga J. 
Published: June 2008

AbstractIn this work, the influence of three different suspension agents (agar, sodium alginate, and gelatin) in the synthesis of poly(methyl methacrylate) (PMMA) particles is reported. Sodium alginate was the best suspension agent, obtaining characteristics closer to commercial denture base resins. Synthesized particles and two commercial acrylic resins (Acron MC and Lucitone 199) were characterized by light microscopy, scanning electron microscopy, characteristic X‐ray energy dispersive spectroscopy, thermogravimetric analysis, and molecular weight measurements. Mechanical tests (transverse deflection behavior) were done using two heat‐polymerizing techniques. The results indicated that both the PMMA particles and the commercial acrylic resins have similar characteristics. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
When “personhood” begins in the embryo: Avoiding a Syllabus of Errors
Authors: Gilbert Scott F. 
Published: June 2008

AbstractThe following essay was delivered at the conference “Ontogeny and Human Life” at the Ponifical Athenaeum “Regina Apostolorum,” November, 2007. Sponsored by the Legion of Christ, the Pontifical Academy for Life, and the John Templeton Foundation, the sessions focused on when the conceptus became a “person.” My essay focused on the scientific conclusions that could aid such discussions. Moreover, after listening to the philosophical, legal, and theological discussions that ensued, I responded theologically as well. New concepts in modern embryology have made scientists revise their views concerning the autonomy of embryos and the mechanisms that generate such embryos. There are interactions between the sperm and the female reproductive tract and egg which had never been known until recently. There are also interactions between the developing organism and its environment that had been unsuspected a decade ago. Gut bacteria induce the development of the mammalian digestive system and immune system by changing the gene expression patterns in the mammalian intestine. Conversely, chemicals in our technological society can adversely affect the embryo, rendering it sterile or prone to tumors later in life. While there is no consensus among scientists as to when human life begins, both Church and science can become allies in persuading governments to regulate or ban the production and use of these fetotoxic chemicals. These new views of embryonic development change many of the stories told about human embryos and fetuses, and they have implications concerning the use of science as evidence for theological positions. Birth Defects Research (Part C) 84:164–173, 2008. © 2008 Wiley‐Liss, Inc.
Cell biology of embryonic migration
Authors: Kurosaka Satoshi , Kashina Anna 
Published: June 2008

AbstractCell migration is an evolutionarily conserved mechanism that underlies the development and functioning of uni‐ and multicellular organisms and takes place in normal and pathogenic processes, including various events of embryogenesis, wound healing, immune response, cancer metastases, and angiogenesis. Despite the differences in the cell types that take part in different migratory events, it is believed that all of these migrations occur by similar molecular mechanisms, whose major components have been functionally conserved in evolution and whose perturbation leads to severe developmental defects. These mechanisms involve intricate cytoskeleton‐based molecular machines that can sense the environment, respond to signals, and modulate the entire cell behavior. A big question that has concerned the researchers for decades relates to the coordination of cell migration in situ and its relation to the intracellular aspects of the cell migratory mechanisms. Traditionally, this question has been addressed by researchers that considered the intra‐ and extracellular mechanisms driving migration in separate sets of studies. As more data accumulate researchers are now able to integrate all of the available information and consider the intracellular mechanisms of cell migration in the context of the developing organisms that contain additional levels of complexity provided by extracellular regulation. This review provides a broad summary of the existing and emerging data in the cell and developmental biology fields regarding cell migration during development. Birth Defects Research (Part C) 84:102–122, 2008. © 2008 Wiley‐Liss, Inc.