bluuebunny/crossref_metadata_2025 huggingface dataset:
Sedentary work, low physical job demand, and obesity in US workers
Authors: Choi BongKyoo , Schnall Peter L. , Yang Haiou , Dobson Marnie , Landsbergis Paul , Israel Leslie , Karasek Robert , Baker Dean
Published: August 2010

Background

Little is known about the role of low physical activity at work (sedentary work or low physical job demand) in the increasing prevalence of obesity of US workers.

Methods

This cross‐sectional and secondary data analysis included 1,001 male and 1,018 female workers (age range: 32–69) from the National Survey of Midlife Development in the United States (MIDUS) II study (2004–2006). Sedentary work and physical job demand were measured by questionnaire items. Total obesity (based on body mass index) and central obesity (based on waist circumference) were defined using WHO criteria.

Results

After controlling for covariates (socio‐demographic, psychosocial working conditions, health status, and health behaviors), sedentary work, low physical job demand, or their combination increased the risk for total and central obesity in male workers, particularly when they worked longer than 40 hr per week. Sedentary work marginally increased the risk for total and central obesity in female workers.

Conclusions

Low physical activity at work is a significant risk factor for total and central obesity in middle‐aged US male workers. Am. J. Ind. Med. 53:1088–1101, 2010. © 2010 Wiley‐Liss, Inc.
Work‐related effort thrombosis in a millwright: A case report
Authors: Pysklywec Michael , Cina Claudio S.
Published: August 2010

Background

Effort thrombosis refers to axillosubclavian vein thrombosis secondary to physical activities of the upper extremity.

Methods

This report describes the clinical presentation of effort thrombosis in a millwright and reviews the literature for occupational reports of this condition.

Results

While there is a paucity of literature reporting an occupational association, work related physical demands on the upper extremity appears to increase the risk of axillosubclavian impingement and thrombosis in certain patients.

Conclusion

Effort thrombosis is a rare vascular condition of the upper extremity that may be seen in workers with repetitive, forceful, or overhead arm activities. Am. J. Ind. Med. 54:244–247, 2011. © 2010 Wiley‐Liss, Inc.
Barriers and enablers to returning to work from long‐term sickness absence: Part I—A quantitative perspective
Authors: Board Belinda J. , Brown Jennifer
Published: August 2010

Background

Long‐term sickness absence (LTSA) in the United Kingdom labor market has become a major health issue in recent years. In contrast to short‐term sickness absence, rates for LTSA have been on the increase. This paper, part 1 of a two‐part paper, identifies individual domain barriers to returning to work (RTW) from LTSA across the work disability timeline in the UK labor market.

Methods

This is a retrospective cohort study of 6,246 workers from an occupationally diverse Police Force within the UK using a large administrative database. A series of chi‐squared analyses were conducted to analyze the between and within group associations. Next, multiple logistic regression analyses using the Enter method were performed to develop a predictive model for RTW and Absence Phase.

Results

Findings substantiated the presence of individual domain barriers to RTW and predictors of RTW outcome and established the absence phase specificity of a number of risk factors of prolonged work disability. In particular, injury/illness especially mental ill health (MIH), physical job demands, sex, and number of episodes of LTSA are significant individual domain barriers to RTW and represent important risk factors for prolonged work disability.

Conclusions

Duration of work disability is associated with medical diagnosis, especially MIH, physical job demands, sex, and number of LTSA episodes. Findings also support the importance of using the outcome measure of absence phase of risk factors in addition to RTW outcome. Am. J. Ind. Med. 54:307–324, 2011. © 2010 Wiley‐Liss, Inc.
Craniofacial birth defects: The role of neural crest cells in the etiology and pathogenesis of Treacher Collins syndrome and the potential for prevention
Authors: Trainor Paul A.
Published: August 2010

Of all the babies born with birth defects, approximately one‐third display anomalies of the head and face [Gorlin et al., 1990] including cleft lip, cleft palate, small or absent facial and skull bones and improperly formed nose, eyes, ears, and teeth. Craniofacial disorders are a primary cause of infant mortality and have serious lifetime functional, esthetic, and social consequences that are devastating to both children and parents alike. Comprehensive surgery, dental care, psychological counseling, and rehabilitation can help ameliorate‐specific problems but at great cost over many years which dramatically affects national health care budgets. For example, the Center for Disease Control and Prevention estimates that the lifetime cost of treating the children born each year with cleft lip and/or cleft palate alone to be US$697 million. Treating craniofacial malformations, of which in excess of 700 distinct syndromes have been described, through comprehensive, well‐coordinated and integrated strategies can provide satisfactory management of individual conditions, however, the results are often variable and rarely fully corrective. Therefore, better techniques for tissue repair and regeneration need to be developed and therapeutic avenues of prevention need to be explored in order to eliminate the devastating consequences of head and facial birth defects. To do this requires a thorough understanding of the normal events that control craniofacial development during embryogenesis. This review therefore focuses on recent advances in our understanding of the basic etiology and pathogenesis of a rare craniofacial disorder known as Treacher Collins syndrome and emerging prospects for prevention that may have broad application to congenital craniofacial birth defects. © 2010 Wiley‐Liss, Inc.
A novel EFNB1 mutation (c.712delG) in a family with craniofrontonasal syndrome and diaphragmatic hernia
Authors: Hogue Jacob , Shankar Suma , Perry Hazel , Patel Reena , Vargervik Karin , Slavotinek Anne
Published: August 2010

We report on the occurrence of congenital diaphragmatic hernia in a family with craniofrontonasal syndrome found to have a previously unreported mutation in EFNB1. The female proband presented with hypertelorism, telecanthus, bifid nasal tip, widow's peak, frontal bossing, and a widened metopic suture. Her father was noted to have hypertelorism, telecanthus, widow's peak, and a history of pectus carinatum. He was found to have a previously unreported mutation in exon 5 of EFNB1 predicted to cause premature protein truncation. The parents of the proband previously had a female fetus with congenital diaphragmatic hernia. The occurrence of congenital diaphragmatic hernia, phenotypic differences between males and females, and utility of molecular testing in craniofrontonasal syndrome are demonstrated. © 2010 Wiley‐Liss, Inc.
Caudal dysgenesis and sirenomelia‐single centre experience suggests common pathogenic basis
Authors: Thottungal Anjana D. , Charles Adrian K. , Dickinson Jan E. , Bower Carol
Published: August 2010

Abnormally formed lower limbs with varying degrees of fusion are the major feature of sirenomelia whereas maldeveloped lower limbs without fusion are found in association with caudal dysgenesis (CD). The relationship between these two entities has been a topic of debate for many years. The presence of a single umbilical artery originating from the abdominal aorta was considered a major feature distinguishing sirenomelia from CD. Based on this finding, the vascular steal theory was put forward as the causative mechanism of sirenomelia. CD and sirenomelia were considered to be two entirely different entities with distinct pathogenic mechanisms. However, it is now clear that a single umbilical artery can be found in some patients of CD and normal umbilical arteries in some patients of sirenomelia. The hypothesis of primary deficiency of caudal mesoderm caused by early developmental disruption suggests that sirenomelia and CD are two ends of a spectrum of maldevelopment of caudal mesoderm. In this paper we report on the clinical and pathological features of 16 patients of CD and 9 patients of sirenomelia from our institution and review the literature. This series of cases is notable for the significant association with neural tube defects, refining the renal and urogenital pathology associated with these conditions, and supporting the concept of a continuum of the disease spectrum. © 2010 Wiley‐Liss, Inc.
Clericuzio‐type poikiloderma with neutropenia syndrome in three sibs with mutations in the C16orf57 gene: Delineation of the phenotype
Authors: Concolino D. , Roversi G. , Muzzi G.L. , Sestito S. , Colombo E.A. , Volpi L. , Larizza L. , Strisciuglio P.
Published: August 2010

We report on three sibs who have autosomal recessive Clericuzio‐type poikiloderma neutropenia (PN) syndrome. Recently, this consanguineous family was reported and shown to be informative in identifying the C16orf57 gene as the causative gene for this syndrome. Here we present the clinical data in detail. PN is a distinct and recognizable entity belonging to the group of poikiloderma syndromes among which Rothmund–Thomson is perhaps the best described and understood. PN is characterized by cutaneous poikiloderma, hyperkeratotic nails, generalized hyperkeratosis on palms and soles, neutropenia, short stature, and recurrent pulmonary infections. In order to delineate the phenotype of this rare genodermatosis, the clinical presentation together with the molecular investigations in our patients are reported and compared to those from the literature. © 2010 Wiley‐Liss, Inc.
Somatic mosaicism for chromosome X and Y aneuploidies in monozygotic twins heterozygous for sickle cell disease mutation
Authors: Razzaghian Hamid Reza , Shahi Mehdi Hayat , Forsberg Lars A. , de Ståhl Teresita Diaz , Absher Devin , Dahl Niklas , Westerman Maxwell P. , Dumanski Jan P.
Published: August 2010

Somatic genetic variation in health and disease is poorly explored. Monozygotic (MZ) twins are a suitable model for studies of somatic mosaicism since genetic differences in twins derived from the same zygote represent an irrefutable example of somatic variation. We report the analysis of a pair of generally healthy female MZ twins, discordant for somatic mosaicism for aneuploidy of chromosomes X and Y. Both twins are heterozygous carriers of sickle cell disease mutation. Genotyping of blood DNA from both twins using Illumina Human 610 SNP array revealed a copy number imbalance for chromosome X in a proportion of cells in one twin. Fluorescent in situ hybridization (FISH) analysis confirmed monosomy X (45,X) in 7% of proband nucleated blood cells. Unexpectedly, FISH analysis of cells from the other twin revealed 45,X and 46,XY lineages, both present in 1% of cells. The mechanism behind formation of these aneuploidies suggests several aberrant chromosome segregation events in meiosis and mitoses following conception. Our report contributes to the delineation of the frequency of somatic structural genomic variation in normal MZ twins. These results also illustrate the plasticity of the human genome for tolerating large copy number changes in healthy subjects and show the sensitivity of the Illumina platform for detection of aberrations that are present in a minority of the studied cells. © 2010 Wiley‐Liss, Inc.
Recurrence risk for offspring of twins discordant for oral cleft: A population‐based cohort study of the Danish 1936–2004 cleft twin cohort
Authors: Grosen Dorthe , Bille Camilla , Pedersen Jacob Krabbe , Skytthe Axel , Murray Jeffrey C , Christensen Kaare
Published: August 2010

Our objective in this Danish population‐based cohort study was to estimate the recurrence risk of isolated oral cleft (OC) for offspring of the unaffected co‐twins of OC discordant twin pairs and to compare this risk to the recurrence risk in the offspring of the affected co‐twin as well as to the risk in the background population. During 1936–2004, 207 twin pairs were ascertained, among whom at least one twin had an OC. The index persons were twins discordant for OC who had children (N = 117), and their offspring (N = 239). The participants were ascertained by linkage between The Danish Facial Cleft Database, The Danish Twin Registry and The Danish Civil Registration System. In the study OC recurrence risk for offspring of the affected and unaffected twin and relative risk were compared to the background prevalence. We found that among 110 children of the 54 OC affected twins, two (1.8%) children had OC corresponding to a significantly increased relative risk (RR = 10; 95% CI 1.2–35) when compared to the frequency in the background population. Among the 129 children of the 63 unaffected twins, three (2.3%) children were affected, corresponding to a significantly increased relative risk (RR = 13; 95% CI 2.6–36) when compared the background prevalence. We concluded that in OC discordant twin pairs similar increased recurrence risks were found among offspring of both OC affected and OC unaffected twins. This provides further evidence for a genetic component in cleft etiology and is useful information for genetic counseling of twin pairs discordant for clefting. © 2010 Wiley‐Liss, Inc.
A de novo p.Asp18Asn mutation in TREX1 in a patient with Aicardi–Goutières syndrome
Authors: Haaxma Charlotte A. , Crow Yanick J. , van Steensel Maurice A.M. , Lammens Martin M.Y. , Rice Gillian I. , Verbeek Marcel M. , Willemsen Michèl A.A.P.
Published: August 2010

Aicardi–Goutières syndrome is a rare, genetically determined encephalopathy often resembling congenital infection. Mutations in the TREX1 gene are found in approximately 25% of patients. Aicardi–Goutières syndrome is usually inherited as an autosomal recessive trait, although a single case of a heterozygous TREX1 mutation associated with the syndrome has been reported. We present a second case of a de novo heterozygous TREX1 mutation causing an autosomal dominant phenotype of Aicardi–Goutières syndrome with additional features indicative of mitochondrial dysfunction. This report serves to enhance awareness of de novo heterozygous mutations underlying Aicardi–Goutières syndrome—with a concomitant low risk of recurrence. © 2010 Wiley‐Liss, Inc.
De novo ACTA2 mutation causes a novel syndrome of multisystemic smooth muscle dysfunction
Authors: Milewicz Dianna M. , Østergaard John R. , Ala‐Kokko Leena M. , Khan Nadia , Grange Dorothy K. , Mendoza‐Londono Roberto , Bradley Timothy J. , Olney Ann Haskins , Adès Lesley , Maher Joseph F. , Guo Dongchuan , Buja L. Maximilian , Kim Dong , Hyland James C. , Regalado Ellen S.
Published: August 2010

Smooth muscle cells (SMCs) contract to perform many physiological functions, including regulation of blood flow and pressure in arteries, contraction of the pupils, peristalsis of the gut, and voiding of the bladder. SMC lineage in these organs is characterized by cellular expression of the SMC isoform of α‐actin, encoded by the ACTA2 gene. We report here on a unique and de novo mutation in ACTA2, R179H, that causes a syndrome characterized by dysfunction of SMCs throughout the body, leading to aortic and cerebrovascular disease, fixed dilated pupils, hypotonic bladder, malrotation, and hypoperistalsis of the gut and pulmonary hypertension. © 2010 Wiley‐Liss, Inc.
Intentional cutmarks on an early mesolithic human calvaria from Margaux Cave (Dinant, Belgium)
Authors: Toussaint Michel
Published: August 2010

Margaux Cave (Belgium) yielded a Pre‐Boreal Early Mesolithic burial covered by what resembled a burial mound. The hundreds of human bones excavated belonged to 7 to 10 adult females. Among these bones, the CR3 cranium presents numerous cutmarks on both zygomatic processes, on the frontal squama and along the two coronal sutures, as well as on the left part of the posterior cranium. The cutmarks on the zygomatic processes correspond to the removal of the mandible while those on the top of the forehead and the occipital may result from the removal of the scalp. Therefore, these cutmarks may be interpreted as part of a mortuary ritual. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.
Surnames in Bolivia: A study of the population of Bolivia through isonymy
Authors: Rodriguez‐Larralde Alvaro , Dipierri José , Gomez Emma Alfaro , Scapoli Chiara , Mamolini Elisabetta , Salvatorelli Germano , De Lorenzi Sonia , Carrieri Alberto , Barrai Italo
Published: August 2010

In Bolivia, the Hispanic dual surname system is used. To describe the isonymic structure of Bolivia, the surname distribution of 12,139,448 persons registered in the 2006 census data was studied in 9 districts and 112 provinces of the nation, for a total of 23,244,064 surnames. The number of different surnames found was 174,922. Matrices of isonymic distances between the administrative units (districts and provinces) were constructed and tested for correlation with geographic distance. In the 112 provinces, isonymic distances were correlated with geographic distance (r = 0.545 ± 0.011 for Euclidean, 0.501 ± 0.012 for Nei's, and 0.556 ± 0.010 for Lasker's distance). The multiple regression of the surname effective number (α), equivalent to the allele effective number in a genetic system, was nonsignificant on latitude and longitude; however, it was highly significant and negative on altitude (r = −0.72). Because the Andes extend from north to south in west‐central Bolivia, random inbreeding was lowest in the eastern districts, and highest in mountainous western Bolivia. Average α for the provinces was 122 ± 2; for the districts, it was 216 ± 29, and for the whole of Bolivia it was 213. The geographical distribution of α in the provinces is compatible with the settlement of subsequent groups of migrants moving from east and north toward the center and south of Bolivia. The relative frequency of indigenous surnames is correlated positively with altitude. This suggests that the country was populated by recent low‐density demic diffusion over a low‐density indigenous population. This may have been a common phenomenon in the immigration to tropical South America. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.
Species co‐occurrence patterns and dietary resource competition in primates
Authors: Kamilar Jason M. , Ledogar Justin A.
Published: August 2010

Diamond (Assembly of species communities. In: Cody ML, Diamond JM, editors. Ecology and evolution of communities. Cambridge: Belknap. p 342–444 (1975)) argued that interspecific competition between species occupying similar niches results in a nonrandom pattern of species distributions. In particular, some species pairs may never be found in the same community due to competitive exclusion. Rigorous analytical methods have been developed to investigate the possible role that interspecific competition has on the evolution of communities. Many studies that have implemented these methods have shown support for Diamond's assembly rules, yet there are numerous exceptions. We build on this previous research by examining the co‐occurrence patterns of primate species in 109 communities from across the world. We used EcoSim to calculate a checkerboard (C) score for each region. The C score provides a measure of the proportion of species pairs that do not co‐occur in a set of communities. High C scores indicate that species are nonrandomly distributed throughout a region, and interspecific competition may be driving patterns of competitive exclusion. We conducted two sets of analyses. One included all primate species per region, and the second analysis assigned each species to one of four dietary guilds: frugivores, folivores, insectivores, and frugivore‐insectivores. Using all species per region, we found significantly high C scores in 9 of 10 regions examined. For frugivores, we found significantly high‐C scores in more than 50% of regions. In contrast, only 23% of regions exhibited significantly high‐C scores for folivores. Our results suggest that communities are nonrandomly structured and may be the result of greater levels of interspecific competition between frugivores compared to folivores. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.
Differential visibility of treponemal disease in pre‐Columbian stratified societies: Does rank matter?
Authors: Smith Maria Ostendorf , Betsinger Tracy K. , Williams Leslie Lea
Published: August 2010

Treponemal disease is known to be associated with the compromised community health of permanent village settlement. This association explains its high visibility in the village‐based, arguably chiefdom level, agriculturalist societies of late prehistoric (AD 1300–1600) North America. Within chiefdom‐level societies, health differences have often been demonstrated between mortuary‐defined “elite” and “nonelite” individuals. This theoretically should predict status‐based differences in treponemal disease visibility. The prediction is tested in a five‐site osteological sample (N = 650) from the Dallas phase (AD 1300–1550), a simple mortuary‐defined two‐tiered presumptive chiefdom level maize agriculturalist socioeconomic context from lower east Tennessee. The Dallas phase results affirm a general pre‐Colombian North American pattern of no sex differences and display comparable adult to subadult frequencies. The study also reveals that given a sufficient sample size, “elites” do indeed exhibit a significantly lower frequency of tertiary stage treponemal disease. This can be attributed to better baseline health, which has been previously demonstrated in this sample. It may also be affected by the mortuary inclusion of achieved status individuals whose good health may have facilitated sociopolitical advancement. Another pattern that emerged is an apparent young adult age bias in disease visibility. This suggests that tertiary treponemal disease morbidity may either directly or synergistically factor in early adult age at death. Future research will address the veracity of this association. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.
Human deciduous mandibular molar incremental enamel development
Authors: Mahoney Patrick
Published: August 2010

Quantitative studies of incremental markings retained within human enamel have reconstructed the duration and rate (crown and cusp formation times, initiation and completion, daily enamel secretion rates) of permanent tooth development. This approach has provided one way of estimating human age‐at‐death, and facilitated comparative dental studies of primate evolution. Similar applications from deciduous enamel are inhibited because developmental reconstructions from incremental markings for these teeth are less frequently reported in the literature. This study quantified the duration and rate of enamel development for mesial (protoconid, metaconid) and distal cusps (hypoconid, entoconid) for first (dm1) and second (dm2) deciduous mandibular molars from an archaeological sample of modern human juveniles. Crown formation time can be calculated from the dm1 protoconid because growth initiates and completes in this cusp, and from the dm2 protoconid combined with the final period of hypoconid growth. The dm1 postnatal crown formation time included the time taken for the tubercle of Zuckerkandl to develop, and differed slightly compared to radiographic methods. The majority of dm1 protoconid cuspal (occlusal region) enamel formed before birth. The dm2 entoconid enamel formed mainly after birth. Birth reduced daily enamel secretion rates, changed the visibility of incremental markings, and disrupted enamel growth for 3 to 8 days. Findings presented here can contribute to age‐at‐death estimates for human infants aged 13‐postnatal months or less, and should facilitate comparisons of primate deciduous incremental enamel development in an evolutionary context. Regression equations are included so that cuspal formation time can be estimated from enamel thickness. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.
Assessment of JC virus DNA in blood and urine from natalizumab‐treated patients
Authors: Rudick Richard A. , O'Connor Paul W. , Polman Chris H. , Goodman Andrew D. , Ray Soma S. , Griffith Nancy M. , Jurgensen Stephanie A. , Gorelik Leonid , Forrestal Fiona , Sandrock Alfred W. , Goelz Susan E.
Published: August 2010

Objective

Analyses were conducted to determine the clinical utility of measuring JC virus (JCV) DNA in blood or urine of natalizumab‐treated multiple sclerosis (MS) patients to predict the risk of progressive multifocal leukoencephalopathy (PML).

Methods

A total of 12,850 blood and urine samples from nearly 1,400 patients participating in natalizumab clinical trials were tested for JCV DNA using a commercially available quantitative polymerase chain reaction (qPCR) assay. A subset of these samples was also tested using a more sensitive qPCR assay developed at the National Institutes of Health (NIH).

Results

At the time natalizumab dosing was suspended, JCV DNA was detected in plasma by the commercial assay in 4 of 1,397 (0.3%) patients; the NIH assay confirmed these positive samples and detected JCV DNA in an additional 2 of 205 (1%) patients who tested negative with the commercial assay. None of these 6 JCV DNA positive patients developed PML. In a 48‐week study testing the safety of natalizumab redosing, JCV DNA was detected in plasma of 6 of 1,094 (0.3%) patients, none of whom developed PML. Urine at baseline and week 48 was assessed in 224 patients; 58 (26%) were positive at baseline, and 55 (25%) were positive after 48 weeks of natalizumab, treatment. JCV DNA was not detected in peripheral blood mononuclear cells from any of these 1,094 patients before or after natalizumab treatment. In 5 patients who developed PML, JCV DNA was not detected in blood at any time point before symptoms first occurred.

Interpretation

Measuring JCV DNA in blood or urine with currently available methods is unlikely to be useful for predicting PML risk in natalizumab‐treated MS patients. Ann Neurol 2010
Anti‐JC virus antibodies: Implications for PML Risk Stratification
Authors: Gorelik Leonid , Lerner Michaela , Bixler Sarah , Crossman Mary , Schlain Brian , Simon Kenneth , Pace Amy , Cheung Anne , Chen Ling Ling , Berman Melissa , Zein Fairuz , Wilson Ewa , Yednock Ted , Sandrock Alfred , Goelz Susan E. , Subramanyam Meena
Published: August 2010

Objective

A study was undertaken to establish an enzyme‐linked immunosorbent assay (ELISA) to detect JC virus (JCV)‐specific antibodies in multiple sclerosis (MS) patients, and to evaluate its potential utility for identifying patients at higher or lower risk (ie, risk stratification) of developing progressive multifocal leukoencephalopathy (PML).

Methods

A 2‐step assay for detecting and confirming the presence of anti‐JCV antibodies in human serum and plasma was developed and demonstrated to be both sensitive and specific. ELISA cutpoints were statistically established using sera from >800 MS patients from natalizumab clinical studies. Subsequently, this assay was used to determine the presence of anti‐JCV antibodies in natalizumab‐treated PML patients where serum samples were collected 16‐180 months prior to the diagnosis of PML.

Results

In our evaluation of natalizumab‐treated MS patients, 53.6% tested positive for anti‐JCV antibodies, with a 95% confidence interval of 49.9 to 57.3%. The false‐negative rate of the ELISA was calculated to be approximately 2.5%, with an upper 1‐sided confidence limit of 4.4%. Notably, we observed anti‐JCV antibodies in all 17 available pre‐PML sera samples, which was significantly different from the 53.6% seropositivity observed in the overall MS study population (p < 0.0001).

Interpretation

This 2‐step assay provides a means to classify MS patients as having detectable or not detectable levels of anti‐JCV antibodies. The finding that all 17 of the pre‐PML samples that were available tested seropositive, and none tested seronegative, warrants further research on the clinical utility of the anti‐JCV antibody assay as a potential tool for stratifying MS patients for higher or lower risk of developing PML. Ann Neurol 2010
Ni(OAc)2: a highly efficient catalyst for the synthesis of enaminone and enamino ester derivatives under solvent‐free conditions
Authors: Liu Ju‐Yan , Cao Gai‐E , Xu Wei , Cao Jie , Wang Wei‐Lu
Published: August 2010

Ni(OAc)2 was found to be an efficient catalyst for the synthesis of β‐enamino ketones or esters from β‐dicarbonyl compounds and amines under solvent‐free conditions. The reusability of the catalyst was successfully examined without noticeable loss of its catalytic activity. Copyright © 2010 John Wiley & Sons, Ltd.
Catalysis and mechanistic studies of ruthenium and osmium on synthesis of anthranilic acids
Authors: Karthikeyan P. , Jagadeesh Rajenahally V. , Sree Sandhya Y. , Puttaswamy  , Nithya P. , Senthil Kumar S. , Bhagat P.R.
Published: August 2010

Ruthenium, osmium and ruthenium + osmium catalyzed synthetic methodology was developed for the synthesis of anthranilic acids from indoles in good to excellent yields using bromamine‐B in alkaline acetonitrile–water (1:1) at 313 K. Detailed catalysis studies of ruthenium, osmium and the mixture of both were carried out for the synthetic reactions. The positive synergistic catalytic activity of Ru(III) + Os(VIII) was observed to a large extent with the activity greater than the sum of their separate catalytic activities. Detailed kinetic and mechanistic investigations for each catalyzed reactions were carried out. The kinetic pattern and mechanistic picture of each catalyzed reaction were found to be different for each catalyst and to obey the underlying rate laws:

where, x, y < 1. The reactions were studied at different temperatures and the activation parameters were evaluated for each catalyzed reaction. Under the identical set of experimental conditions, the kinetics of all the three catalyzed reactions were compared with uncatalyzed reactions, revealing that the catalyzed reactions were 6‐ to 42‐fold faster. The catalytic efficiency of aforementioned catalysts followed the order: Ru(III) + Os(VIII) > Os(VIII) > Ru(III). This trend may be attributed to the different d‐electronic configuration of the catalysts. The proposed mechanisms and the rigorous kinetic models derived give results that fit well with the experimental data in each catalyzed reaction. Copyright © 2010 John Wiley & Sons, Ltd.
Transfer hydrogenation of citral to citronellol with Ru complexes in the mixed solvent of water and polyethylene glycol
Authors: Cheng Haiyang , Liu Ruixia , Hao Jianmin , Wang Qiang , Yu Yancun , Cai Shuxia , Zhao Fengyu
Published: August 2010

The transfer hydrogenation of citral to citronellol was studied with [RuCl2(benzene)]2 catalyst in a mixed solvent of water and polyethylene glycol (H2OPEG). The influence of several important factors including hydrogen source, solvent, temperature and active species is discussed. Under the present conditions, citronellol was produced with an extremely high selectivity above 90%. The Ru complexes could be immobilized in the H2OPEG phase well and separated from organic products successfully. Moreover, a stable catalytic activity was obtained after the first run, although the decomposition of Ru complexes occurred during the recycling processes. The selectivity to citronellol decreased but kept a stable level about 60% in the recycling runs. Copyright © 2010 John Wiley & Sons, Ltd.
Periodic mesoporous organosilica grafted palladium organometallic complex: efficient heterogeneous catalyst for water‐medium organic reactions
Authors: Huang Jianlin , Zhang Fang
Published: August 2010

Water‐medium organic reactions were studied over periodic mesoporous silica (PMO) containing Pd(II) organometallic complex. This heterogeneous catalyst was achieved by Pd(II) compound coordinated with the PPh2‐ligand onto the pore surface of phenylene‐bridged PMO support. This catalyst displayed ordered mesoporous channels, which ensured the high dispersion of Pd(II) active sites and the convenient diffusion of reactant molecules into the pore channels. Meanwhile, the phenyl group in the pore wall of PMO could enhance the surface hydrophobicity which promoted the adsorption of organic reactant molecules on the catalyst in aqueous environment. As a result, this elaborated catalyst exhibited comparable activity and selectivity with the corresponding PdCl2(PPh3)2 homogeneous catalyst in the water‐medium organic reactions, and could be used repeatedly, showing a good potential in industrial applications. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis, cytotoxicity and antibacterial studies of symmetrically and non‐symmetrically benzyl‐ or p‐cyanobenzyl‐substituted N‐Heterocyclic carbene–silver complexes
Authors: Patil Siddappa , Deally Anthony , Gleeson Brendan , Müller‐Bunz Helge , Paradisi Francesca , Tacke Matthias
Published: August 2010

From the reaction of 1H‐imidazole (1a), 4,5‐dichloro‐1H‐imidazole (1b) and 1H‐benzimidazole (1c) with p‐cyanobenzyl bromide (2), symmetrically substituted N‐heterocyclic carbene (NHC) [(3a–c)] precursors, 1‐methylimidazole (5a), 4,5‐dichloro‐1‐methylimidazole (5b) and 1‐methylbenzimidazole (5c) with benzyl bromide (6), non‐symmetrically substituted N‐heterocyclic carbene (NHC) [(7a–c)] precursors were synthesized. These NHCprecursors were then reacted with silver(I) acetate to yield the NHC‐silver complexes [1,3‐bis(4‐cyanobenzyl)imidazole‐2‐ylidene] silver(I) acetate (4a), [4,5‐dichloro‐1,3‐bis(4‐cyanobenzyl)imidazole‐2‐ylidene] silver(I) acetate (4b), [1,3‐bis(4‐cyanobenzyl)benzimidazole‐2‐ylidene] silver(I) acetate (4c), (1‐methyl‐3‐benzylimidazole‐2‐ylidene) silver(I) acetate (8a), (4,5‐dichloro‐1‐methyl‐3‐benzylimidazole‐2‐ylidene) silver(I) acetate (8b) and (1‐methyl‐3‐benzylbenzimidazole‐2‐ylidene) silver(I) acetate (8c) respectively. The four NHC‐precursors 3a–c, 7c and four NHC–silver complexes 4a–c and 8c were characterized by single crystal X‐ray diffraction. The preliminary antibacterial activity of all the compounds was studied against Gram‐negative bacteria Escherichia coli, and Gram‐positive bacteria Staphylococcus aureus using the qualitative Kirby‐Bauer disc‐diffusion method. All NHC–silver complexes exhibited medium to high antibacterial activity with areas of clearance ranging from 4 to 12 mm at the highest amount used, while the NHC‐precursors showed significantly lower activity. In addition, all NHC–silver complexes underwent preliminary cytotoxicity tests on the human renal‐cancer cell line Caki‐1 and showed medium to high cytotoxicity with IC50 values ranging from 53 ( ± 8) to 3.2 ( ± 0.6) µM. Copyright © 2010 John Wiley & Sons, Ltd.
Heck coupling reaction using monomeric ortho‐palladated complex of 4‐methoxy‐ benzoylmethylenetriphenylphosphorane under microwave irradiation
Authors: Hajipour Abdol R. , Karami Kazem , Tavakoli Ghazal
Published: August 2010

The activity of [Pd(C6H4CH2 NH2‐κ2‐C‐N)PPh3MOBPPY]OTf complex, A (MOBPPY = 4‐methoxybenzoylmethylenetriphenyl‐ phosphoraneylide), was investigated in the Heck–Mizoroki CC cross‐coupling reaction under conventional heating and microwave irradiation conditions. The complex is an active and efficient catalyst for the Heck reaction of aryl halides. The yields were excellent using a catalytic amount of [Pd(C6H4CH2 NH2‐κ2‐C‐N)PPh3MOBPPY]OTf complex in N‐methyl‐2‐pyrrolidinone (NMP) at 130 °C and 600 W. In comparison to conventional heating conditions, the reactions under microwave irradiation gave higher yields in shorter reaction times. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Synthesis of propylene carbonate from carbon dioxide using trans‐dichlorotetrapyridineru‐ thenium(II) as catalyst
Authors: Bu Zhanwei , Wang Zhiqiang , Yang Lirong , Cao Shaokui
Published: August 2010

trans‐Dichlorotetrapyridineruthenium(II) [trans‐RuCl2(py)4] was synthesized and the structure was determined by single crystal X‐ray crystallography. Highly efficient formation of propylene carbonate (PC) from carbon dioxide and propylene oxide was achieved by using a catalyst system composed of trans‐RuCl2(py)4 and hexadecyl trimethyl ammonium bromide under mild conditions (4h, 80 °C, 3.0 MPa). PC was obtained in nearly 100% selectivity without the formation of a polymer. The catalyst could be recycled constantly many times without any significant loss of its catalytic activity. On the basis of the results, a mechanism for the reaction was proposed. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Rapid and efficient protection of alcohols and phenols, and deprotection of trimethylsilyl ethers catalyzed by a cerium‐containing polyoxometalate
Authors: Yadollahi Bahram , Mirkhani Valiollah , Tangestaninejad Shahram , Karimian Davud
Published: August 2010

Herein, we want to report a simple and convenient way for protection‐deprotection of alcohols in the presence of ammonium decatungstocerate(IV) {(NH4)8[CeW10O36]·20H2O} as catalyst under ambient temperature in CH3CN. Using 0.002 mmol of the catalyst, various alcohols and phenols were transformed easily to the corresponding TMS ethers in excellent yields. In the second part, various TMS ethers were successfully converted to the parent hydroxyl compounds in the presence of the ammonium decatungstocerate(IV) catalyst. Copyright © 2010 John Wiley & Sons, Ltd.
An analytical study on settling of non‐spherical particles
Authors: Jalaal M. , Ganji D.D. , Ahmadi G.
Published: August 2010

The clarification of the unsteady falling movement of immersed bodies in fluids occurs in several natural situations and many manufacturing processes, e.g. particulate processing and two‐phase solid–liquid applications. In this paper, the acceleration motion of a spherical particle in an incompressible Newtonian environment has been studied for a wide range of Reynolds numbers using a drag coefficient as defined by Chien [S.F. Chien. SPE Drill. Complet., 1994; 9, 281]. The governing equation is strongly nonlinear due to nonlinear nature of the drag coefficient. An analytical mathematical procedure is performed to express an expression for velocity of the particle during the acceleration motion using variational iteration method. Therefore, both the acceleration and position of the particle were easily obtained. The equation of motion was solved in a general form and also for some realistic solid–liquid combinations. The effects of particle sphericity and continuous‐phase viscosity were investigated for different practical situations, where the results satisfactorily describe the settling behavior of the particle. The results were compared with a numerical method and very good agreement was obtained. This work demonstrates the effectiveness of the current mathematical method and presents a simple approach for this type of problem, where the derived expression can be used in different numerical and analytical surveys. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Morphological evolution of polypropylene/polystyrene blends in a twin‐screw extruder
Authors: Wu Yang , Jing Shaowei , Gu Qun , Li Binyao
Published: August 2010

The effects of the blend composition and rotation speed on the morphological evolution of polypropylene (PP)/polystyrene (PS) blends were investigated in a twin‐screw extruder. When PS was the major component, the rate of melt and the rate of dispersion played final roles in the morphological development of the polymer melts. However, when PP was the major component, the rate of dispersion and the rate of coalescence played key roles. A high tendency to coalesce occurred at a high rotation speed and/or a high content of the dispersed phase. When the PP/PS blend composition was close to 1, a cocontinuous morphology was observed to transmute into a coarse one with increasing rotation speed. Attempts were made to correlate the morphology and mechanical properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Evaluation of the corrosion barrier properties of nano‐reinforced vinyl chloride/vinyl acetate coatings
Authors: Calhoun M. , Ludwick A. , Mahmoud M. , Aglan H.
Published: August 2010

A poly(vinyl chloride/vinyl acetate) copolymer (VYHH) with and without multiwalled carbon nanotubes (MWCNTs) as reinforcements were used as a coating for steel substrates to evaluate their barrier properties against corrosion. Electrical impedance and thermal properties of the coatings were evaluated. The coatings were formulated with 0.1% MWCNT, by weight. Neat and nano‐filled VYHH was used to coat polished, degreased steel substrates via a dipping method. The substrates were either dipped once, for a target coating thickness of 30–40 μm, or twice for a target coating thickness of 60–75 μm. The coated and uncoated control samples were submerged in a tank with a 5% NaCl solution for a 45‐day period. Electrochemical impedance spectroscopy (EIS) revealed that coating thickness plays a role in corrosion resistance. EIS also showed that nano‐reinforced VYHH had the highest charge transfer resistance within its coating thickness. Fourier transform infrared spectroscopy (FTIR) indicated that hydrolysis occurred in the single coatings for both the neat and nanoreinforced coatings. Differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA) both showed that the addition of MWCNTs improved the thermal stability of the VYHH. DSC thermograms revealed that the thermal properties of the nano VYHH were largely unchanged after 45 days of submersion as compared with the unaged nano VYHH. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synthesis and photopolymerization of 2‐(acryloyloxy)ethyl piperidine‐1‐carboxylate and 2‐(acryloyloxy)ethyl morpholone‐4‐carboxylate
Authors: Xiao Ming , Li Zhenfeng , Nie Jun
Published: August 2010

Two low‐viscosity monomers, 2‐(acryloyloxy)ethyl piperidine‐1‐carboxylate (AEPC II) and 2‐(acryloyloxy)ethyl morpholone‐4‐carboxylate (AEMC), were synthesized with a non‐isocyanate route. The photopolymerization kinetics was monitored by real‐time infrared spectroscopy with a horizontal sample holder. The results indicated that AEPC II and AEMC had high ultraviolet curing rates and final double‐bond conversions, which could reach 90 and 95%, respectively. The glass‐transition temperatures of AEPC II/urethane acrylate resin (1/4 w/w), AEMC/urethane acrylate resin (1/4 w/w), and isobornyl acrylate/urethane acrylate resin (1/4 w/w) mixtures were 37.5, 45.6, and 57°C, respectively. The crosslink density of the AEMC/urethane acrylate resin (1/4 w/w) mixture was lower than that of the isobornyl acrylate/urethane acrylate resin (1/4 w/w) mixture. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Modeling processing of silicone rubber: Liquid versus hard silicone rubbers
Authors: Hernández‐Ortiz Juan P. , Osswald Tim A.
Published: August 2010

The processing of hard and liquid silicone rubbers (LSR) are compared by means of modeling and simulation. The curing process for both, hard and liquid silicone, are modeled using the auto‐catalytic Kamal‐Sourour model and a nonlinear regression method is used to find the kinetic parameters. The fitted kinetic model is then combined with the heat balance equations to simulate real processing conditions. Both resins are compared in terms of process performance and consistency of the final part. The results show that even though hard silicone rubbers are less expensive resins, its processing conditions present several issues of consistency and quality control when compared with LSR. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119:1864–1871, 2011
Kinetics study of isothermal nicotine release from poly(acrylic acid) hydrogel
Authors: Adnadjevic Borivoj , Jovanovic Jelena , Lazarevic Natasa
Published: August 2010

The isothermal kinetic of the release of nicotine from a poly(acrylic acid) (PAA) hydrogel was investigated at temperature range from 26°C to 45°C. Specific shape parameters of the kinetic curves, the period of linearity and saturation time were determined. The change in the specific shape parameters of the kinetic curves with temperature and the kinetic parameters of release of nicotine Ea and ln A were determined. By applying the “model fitting” method it was established that the kinetic model of release of nicotine from the PAA hydrogel was [1 − (1 − α)1/3] = kMt. The limiting stage of the kinetics release of nicotine was found to be the contracting volume of the interaction interface. The distribution function of the activation energy was determined and the most probable values of activation energies of 25.5 kJ mol−1 and 35 kJ mol−1 were obtained. Energetically heterogeneity of the interaction interface was explained by the existence of the two different modes of bonding the nicotine molecules onto the hydrogel network by hydrogen bond and electrostatic forces. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Aggregate structure and effect of phthalic anhydride‐modified soy protein on the mechanical properties of styrene‐butadiene copolymer
Authors: Jong Lei
Published: August 2010

The aggregate structure of phthalic anhydride (PA) modified soy protein isolate (SPI) was investigated by estimating its fractal dimension from the equilibrated dynamic strain sweep experiments. The estimated fractal dimensions of the filler aggregates were less than 2, indicating that these particle aggregates have a distorted or broken two‐dimensional sheet‐like structure. The results also indicated that the aggregate structure has a greater effect on the composite reinforcement than the overall aggregate size. Tensile strength, elongation, Young's modulus, and toughness of hydrolyzed/modified soy composites are comparable with those of carbon black reinforced composites at 10–15% filler fraction. The moduli of PA‐modified SPI composites were less sensitive to the pH of the composite preparation compared to the unmodified SPI. The composites prepared at acidic pH, with lower filler fraction, or filled with hydrolyzed/modified SPI are more elastic and less fatigue. The composites of PA‐modified SPI had better recovery properties when prepared at acidic instead of alkali pH. PA‐modified hydrolyzed SPI composites prepared at acidic pH showed a similar recovery property to that of carbon black reinforced composites, but with greater shear elastic moduli. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Study on the effective process parameters influencing styrene and acrylonitrile grafting onto seeded polybutadiene latex
Authors: Abbasi F. , Agah A. M. , Mehravar E.
Published: August 2010

A series of experiments were designed and conducted to determine the significance of process parameters in the grafting of styrene and acrylonitrile onto polybutadiene seeds in a semicontinuous emulsion copolymerization system. The significances of the parameters were obtained by comparing the variance ratios, or F values, with F‐distributions. The significance level of each test (α‐value) was obtained by variance analysis. The important process parameters in industrial polymerization processes are usually monomer‐to‐polymer ratio, initiator type and concentration, chain‐transfer agent, and reaction temperature. The target responses were final monomer conversion, grafting degree, grafting efficiency, gel percent, and viscosity‐average molecular weight of free styrene‐acrylonitrile (SAN). The analysis of variance indicated that cumene hydroperoxide as the initiator and reaction temperature had strong effects on the graft structure. Moreover, free SAN molecular weight was significantly affected by the monomer/polymer ratio and cumene hydroperoxide and n‐dodecyl mercaptan as chain‐transfer agents. The raspberry‐like morphology of grafted acrylonitrile‐butadiene‐styrene (ABS) particles and phase separation within the particles were confirmed by transmission electron microscopy. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011