bluuebunny/crossref_metadata_2025 huggingface dataset:
Outcome of 122 pregnancies in essential thrombocythemia patients: A report from the Italian registry
Authors: Melillo Lorella , Tieghi Alessia , Candoni Anna , Radaelli Franca , Ciancia Rosanna , Specchia Giorgina , Martino Bruno , Scalzulli Potito Rosario , Latagliata Roberto , Palmieri Fausto , Usala Emilio , Valente Daniela , Valvano Maria Rosa , Cedrone Michele , Comitini Giuseppina , Martinelli Vincenzo , Cascavilla Nicola , Gugliotta Luigi
Published: July 2009

Pregnancy is a high‐risk event in women with essential thrombocythemia (ET). This observational study evaluated pregnancy outcome in ET patients focusing on the potential impact of aspirin (ASA) or interferon alpha (IFN) treatment during pregnancy. We retrospectively analyzed 122 pregnancies in 92 women consecutively observed in the last 10 years in 17 centers of the Italian thrombocythemia registry (RIT). The live birth rate was 75.4% (92/122 pregnancies). The risk of spontaneous abortion was 2.5‐fold higher than in the control population (P < 0.01). ASA did not affect the live birth rate (71/93, 76.3% vs. 21/29, 72.4%, P = 0.67). However, IFN treatment during pregnancy was associated with a better outcome than was management without IFN (live births 19/20, 95% vs. 73/102, 71.6%, P = 0.025), and this finding was supported by multivariate analysis (OR: 0.10; 95% CI: 0.013–0.846, P = 0.034). The JAK2 V617F mutation was associated with a poorer outcome (fetal losses JAK2 V617F positive 9/25, 36% vs. wild type 2/24, 8.3%, P = 0.037), and this association was still significant after multivariate analysis (OR: 6.19; 95% CI: 1.17–32.61; P = 0.038). No outcome concordance between first and second pregnancies was found (P = 0.30). Maternal complications occurred in 8% of cases. In this retrospective study, in consecutively observed pregnant ET patients, IFN treatment was associated with a higher live birth rate, while ASA treatment was not. In addition, the JAK2 V617F mutation was confirmed to be an adverse prognostic factor. Am. J. Hematol. 2009. © 2009 Wiley‐Liss, Inc.
Temporary workers in Washington State
Authors: Smith Caroline K. , Silverstein Barbara A. , Bonauto David K. , Adams Darrin , Fan Z. Joyce
Published: July 2009

Background

Evidence regarding the unequal burden of occupational injuries between workers employed by temporary agencies and those in standard employment arrangements is unclear. Studies range from no significant differences in risk to substantial increased risk for temporary workers. The purpose of this study is to compare the workers' compensation experience of a large cohort of temporary agency employed workers with those in standard forms of employment.

Methods

Washington State Fund workers' compensation data were obtained for claims with injury dates from January 1, 2003 to June 30, 2006, resulting in 342,540 accepted claims. General descriptive statistics, injury rates (per 10,000 FTE), and rate ratios (temp agency/standard employer) were computed by injury type and industry.

Results

Temporary agency employed workers had higher rates of injury for all injury types, and higher median time loss (40 vs. 27 days) but lower time loss costs (median $1,224 vs. $1,914, P < 0.001) and lower medical costs ($3,026 vs. $4,087, P < 0.001) than standard arrangement workers. Temporary agency workers had substantially higher rates for “caught in” and “struck by” injuries in the construction (IRR 4.93; 95% CI 2.80–8.08) and manufacturing (IRR 4.05; 95% CI 3.25, 5.00) industry sectors.

Conclusion

Temporary agency employed workers have higher claims incidence rates than those in standard employment arrangements. The rate ratios are twofold higher in the construction and manufacturing industry sectors. More research is needed to explore potential reasons for this disparity in occupational injuries. Industry or some measure of job exposure should be included when comparing injury rates in different types of employment in order to better identify areas for prevention. Am. J. Ind. Med. 53:135–145 2010. © 2009 Wiley‐Liss, Inc.
Iris hyperpigmentation in a Chinese family with ocular albinism and the GPR143 mutation
Authors: Xiao Xueshan , Zhang Qingjiong
Published: July 2009

X‐linked ocular albinism (OA1) is the most common form of ocular albinism. Affected males are characterized by nystagmus, impaired visual acuity, iris hypopigmentation with translucency, fundus hypopigmentation, macular hypoplasia, and normally pigmented skin and hair. However, OA1 has rarely been reported in China. Here, we report on a Chinese family with OA1 and partial deletion of GPR143. An unusual phenotype of iris hyperpigmentation without translucency was observed in the male patient and the carrier mother. There was apparent mosaic pigmentation of the fundus. Our results demonstrate atypical manifestation of OA1 that might enrich our knowledge of phenotypic variation of OA1 among the Chinese population. © 2009 Wiley‐Liss, Inc.
Evolution of a patient with Bohring–Opitz syndrome
Authors: Pierron Sophie , Richelme Christian , Triolo Valérie , Mas Jean Christophe , Griffet Jacques , Karmous‐Benailly Houda , Quere M. , Kaname Tadashi , Lambert Jean‐Claude , Giuliano Fabienne
Published: July 2009

We detailed the story from birth to the age of 5 years 9 months, of the oldest patient reported with a Bohring‐Opitz syndrome with the three main diagnostic criteria: characteristic facial appearance, fixed contractures of the upper limbs and severe feeding difficulties. The facial anomalies described in our patient were microcephaly, bitemporal narrowing, “puffy” cheeks, forehead naevus flammeus, hypoplastic orbital ridges, prominent eyes, broad nasal bridge, high arched palate, buccal‐alveola frenula and retrognathism. The magnetic resonance imaging (MRI) of the brain showed a hypoplastic corpus callosum and a narrowed upper cervical canal; and the cervical MRI showed a malformation of the atlas consisting in an agenesis of the anterior arch and an anterior slip of the posterior arch. We focused on her neurological and nutritional evolution. Despite the gastrostomy and a Nissen fundoplication at age 7 months, she still had developmental growth delays overall (<3rd centile). At 3 years 9 months of age, she began to put on weight quickly, which seemed to be atypical. Meanwhile she developed epilepsy, which was controlled with specific drugs. Currently, she is 5 years 9 months old and has significant psychomotor retardation, although this disease is often fatal in early childhood, due to obstructive apnea and unexplained bradycardia. © 2009 Wiley‐Liss, Inc.
Functional disomy of proximal Xp causes a distinct phenotype comprising early hypotonia, hypertelorism, small hands and feet, ear abnormalities, myopia and cognitive impairment
Authors: Hunter Matthew , Bruno Damien , Amor David J.
Published: July 2009

Extra structurally abnormal chromosomes (ESACs) derived from the X chromosome are rare. We report a non‐mosaic ESAC derived from the X chromosome in a 3‐year‐old female who presented with early hypotonia, developmental delay, hypertelorism, low set ears, and small hands and feet. The breakpoints of the ESAC were mapped by SNP microarray to Xp11.1‐p11.22, a region encompassing 7.17 Mb and containing 110 known or putative genes and excluding the X‐inactivation center. A review of other reported patients with karyotypes that cause functional disomy of proximal Xp allows delineation of a common phenotype comprising early hypotonia, cognitive impairment, hypertelorism, myopia, small hands and feet and abnormal external ears. © 2009 Wiley‐Liss, Inc.
Mosaic trisomy 1q: The longest surviving case
Authors: Patel Chirag , Hardy Graham , Cox Phillip , Bowdin Sarah , McKeown Carole , Russell Alison Bedford
Published: July 2009

We present the longest known surviving case of a male infant with a mosaic complete trisomy 1q. Born at 39 weeks of gestation with respiratory distress, his weight was 3,330 g (25th centile); he had micrognathia, a posterior cleft of palate, abnormal ears and left thumb, syndactyly, and an absent corpus callosum. Initial blood karyotype was normal (46,XY). He died at age 5 months. Autopsy suggested aspiration as the primary cause of death and confirmed the antemortem findings of an absent corpus callosum and atrial septal defect. It also identified some central nervous system, cardiac, gastrointestinal, and lung anomalies not previously recognized. Cytogenetic analysis of skin fibroblasts obtained at autopsy showed a de novo unbalanced translocation between chromosomes 1 and 22: 46,XY,+1,der(1;22)(q10;q10)[25]/46,XY[65] in the cells examined. The previously reported cases had a similar phenotype with birth weight above the 50th centile for gestational age, small mouth, micrognathia, abnormal ears, abnormal fingers, microphthalmia, and hydrocephalus. The present case and a review of the literature delineates the phenotype in trisomy 1q, and reinforces the critical importance of effective communication between specialists, and obtaining permission for autopsy and skin biopsy, in the pursuit of a diagnosis. © 2009 Wiley‐Liss, Inc.
Darier disease, multiple bone cysts, and aniridia due to double de novo heterozygous mutations in ATP2A2 and PAX6
Authors: Castori Marco , Barboni Luana , Duncan Philippa J. , Paradisi Mauro , Laino Luigi , De Bernardo Carmelilia , Robinson David O. , Grammatico Paola
Published: July 2009

Darier disease (DD) is an autosomal dominant genodermatosis caused by mutations in ATP2A2 and characterized by multiple warty papules coalescing in seborrheic areas and specific histological skin changes. Rare patients are described with variable bone involvement, but this association has never been sufficiently emphasized. Aniridia is a developmental disorder of the eye due to heterozygous mutations in PAX6. DD and aniridia are Mendelian traits mapping on independent loci and have never been reported in association. Here, we describe a 14‐year‐old girl showing the unique combination of DD, multiple bone cysts, and bilateral aniridia. Molecular investigations demonstrated that such a complex phenotype is due to double de novo heterozygous mutations in ATP2A2 and PAX6. Review of the literature indicates that, in DD, bone cysts are true developmental abnormalities of the skeleton. This finding suggests a role for ATP2A2 in bone biology. More systematic studies are expected in order to estimate the true prevalence of bone cysts in DD and the relationship between skeletal changes and ATP2A2 perturbation. © 2009 Wiley‐Liss, Inc.
Oculocutaneous albinism type IV: A boy of Moroccan descent with a novel mutation in SLC45A2
Authors: Konno Takayuki , Abe Yuko , Kawaguchi Masakazu , Storm Katrien , Biervliet Martine , Courtens Winnie , Kono Michihiro , Tomita Yasushi , Suzuki Tamio
Published: July 2009

Oculocutaneous albinism type IV (OCA4 [MIM606574]) caused by mutations of the SLC45A2 gene is an autosomal recessive disorder of pigmentation characterized by reduced biosynthesis of melanin pigment in the skin, hair, and eye. We had the opportunity to examine a Belgian boy of Moroccan descent with clinically severe OCA and screened the mutation in his SLC45A2 gene. Sequencing of exon 1, of which the PCR product showed aberrant patterns in the SSCP gel, revealed that the patient was a homozygote for p.H38R mutation. We demonstrated that the p.H38R‐mutant protein was functionally incapable of melanin synthesis using melanocyte cultures (under white cells; uw) established from a mouse model of OCA4. This is the second report of the occurrence of OCA4 in a member of an African ethnic group. © 2009 Wiley‐Liss, Inc.
3q29 microdeletion: A mental retardation disorder unassociated with a recognizable phenotype in two mother–daughter pairs
Authors: Digilio Maria Cristina , Bernardini Laura , Mingarelli Rita , Capolino Rossella , Capalbo Anna , Giuffrida Maria Grazia , Versacci Paolo , Novelli Antonio , Dallapiccola Bruno
Published: July 2009

The 3q29 microdeletion syndrome (del 3q29) is a novel genomic disorder identified after the introduction of microarray‐based technology. The phenotype of the reported patients is variable, including mental retardation and subtle facial anomalies. We report on two mother–daughter pairs, heterozygous for 3q29, and review clinical features of all known affected individuals. Del 3q29 syndrome is associated with nonspecific clinical features, including mild‐to‐moderate developmental delay, microcephaly, and mild facial dysmorphisms such as short philtrum and high nasal bridge. Facial anomalies were nonoverlapping and nondistinct, also within each mother–daughter pair. Parental transmission of del 3q29 could be more frequent than previously considered. Malformations are rare, occurring only in single subjects. The phenotypic diversity of affected patients and the lack of distinct dysmorphisms suggest that this disorder cannot be recognized on clinical ground alone. Del 3q29 should be searched in subjects with unexplained mild/moderate mental retardation, microcephaly, and minor nonspecific facial anomalies. © 2009 Wiley‐Liss, Inc.
Experience with hemihyperplasia and Beckwith–Wiedemann syndrome surveillance protocol
Authors: Zarate Yuri A. , Mena Rafael , Martin Lisa J. , Steele Paul , Tinkle Bradley T. , Hopkin Robert J.
Published: July 2009

Beckwith–Wiedemann syndrome (BWS) and isolated hemihyperplasia (IHH) are two well known overgrowth conditions that are associated with cancer predisposition. Multiple surveillance protocols have been proposed to detect the most commonly reported tumor types Wilms tumor and hepatoblastoma. We reviewed the history of our patients who were part of this monitoring protocol. Information from 63 cases was collected retrospectively while another 63 control samples for AFP measurement were obtained prospectively. Twenty‐five (40%) patients had an ultrasound abnormality, the most frequent being nephromegaly/size discrepancy. Two patients had well documented cases of tumors/tumor precursor (2/63:3.2%) detected by ultrasound images. Three hundred thirty‐six separate AFP values were available with values above 50,000 ng/ml seen in three patients older than 2 months, one with hepatoblastoma and two other with hemangiomas/hemangioendotheliomas. There was no clear difference in the range of AFP values between previously reported controls, our own normal population and affected patients. In conclusion, ultrasound surveillance detected renal and liver pathology including benign and malignant lesions. The known variability of AFP in normal neonates and patients with BWS makes interpretation difficult in early infancy. Very high AFP values did seem to be correlated with risk for identifiable liver lesions. Determination of the natural changes in AFP levels over time will allow more appropriate comparison. © 2009 Wiley‐Liss, Inc.
Partial trisomy 19p13.3 and partial monosomy 1p36.3: Clinical report and a literature review
Authors: Puvabanditsin Surasak , Garrow Eugene , Brandsma Erik , Savla Jayshree , Kunjumon Bgee , Gadi Inder
Published: July 2009

We report on a 15‐month‐old girl with a deletion of the distal short arm of chromosome 1p36.3, partial trisomy of the short arm of chromosome 19p13.3, growth and developmental delay, and multiple anomalies including microcephaly, bifrontal prominence, obtuse frontonasal angle, short columella, hypertelorism, sacral dimples, and a bicuspid pulmonary valve. Based on our FISH mapping studies, we estimate the size of the trisomic region of 19p.13.3 to be ∼3.17 Mb, and the region of monosomy for 1p36.3 as 1.3 Mb. This is the first report of a patient with partial trisomy 19p13.3 and partial monosomy p36.3. © 2009 Wiley‐Liss, Inc.
Evaluating for long‐term impact of an environmental education program at the Kalinzu Forest Reserve, Uganda
Authors: Kuhar C.W. , Bettinger T.L. , Lehnhardt K. , Tracy Osuo , Cox D.
Published: July 2009

Although the importance of evaluating the effectiveness of conservation education programs cannot be underestimated, few evaluations of these programs and their resulting impact on the environment have been conducted. A partnership between scientists, educators, and local administrators on an evaluation program has been developed to evaluate a model of education program evaluation that includes short‐ and long‐term evaluation of (1) knowledge and attitude change, (2) behavior change, and (3) positive biological impact. Previous work has shown short‐term knowledge retention from this education program. In the current study follow‐up evaluations were collected from students at 14 schools outside the Kalinzu Forest Reserve, Uganda. By comparing performance 30 days, 1 year and 2 years after the initial program we demonstrate that knowledge gain from this program is not transient. However, although knowledge is a prerequisite for appropriate conservation actions it does not guarantee appropriate behaviors will be performed. Anecdotal evidence of behavior change and positive biological impact is discussed within the context of the challenges with changing behavior and evaluating the true biological impacts of those behaviors. Ultimately, conservation professionals will need to partner with educators and social scientists to effectively measure the impact of conservation education and human‐based conservation programs on primate populations and their habitat. Am. J. Primatol. 72:407–413, 2010. © 2009 Wiley‐Liss, Inc.
Photodissoziation durch UV‐Licht: Anwendungen in der massenspektrometrischen Proteomforschung
Authors: Ly Tony , Julian Ryan R.
Published: July 2009

Die Auswertung aller Informationen in einem Proteom ist eine Herausforderung für die chemische Analyse, doch winkt als Lohn ein enormer Wissenszuwachs. Die Massenspektrometrie bietet eine einmalige Auswahl an Verfahren für verschiedene Ansätze der Proteomanalyse. Vor kurzem wurde gezeigt, dass man mit UV‐Bestrahlung eine eindeutige Fragmentierung von Peptiden und Proteinen induzieren kann. Dabei ist eine unspezifische Dissoziation ebenso möglich wie eine hochspezifische Dissoziation an künstlich eingeführten Chromophoren, nachdem diese ein Photon absorbiert haben. Die Spezifität und Kontrollierbarkeit der Fragmentierung in solchen Experimenten sind besser als bei anderen Fragmentierungsverfahren. Von neuen Methoden, die auf dieser Technik beruhen, erwartet man wichtige Beiträge zur Proteomforschung.
Ultraviolet Photodissociation: Developments towards Applications for Mass‐Spectrometry‐Based Proteomics
Authors: Ly Tony , Julian Ryan R.
Published: July 2009

Unraveling of all of the information contained in proteomes poses a tremendous chemical challenge, which is balanced by the promise of potentially transformational knowledge. Mass spectrometry offers an unprecedented arsenal of tools for diverse proteomic investigations. Recently, it was demonstrated that ultraviolet light can be utilized to initiate unique and potentially useful fragmentations in peptides and proteins. Either nonspecific dissociation or highly specific dissociation at engineered chromophoric sites is possible following photon absorption. The level of specificity and control over fragmentation in these experiments is greater than with other fragmentation methods. Novel techniques made possible by this technology are poised to make substantial contributions to the field of proteomics.
Direct coupling reaction between alcohols and allyltrimethylsilane catalyzed by phosphomolybdic acid
Authors: Kadam Santosh T. , Lee Hanbin , Kim Sung Soo
Published: July 2009

Phosphomolybdic acid (PMA) is a simple and efficient catalyst for direct coupling reaction of alcohols with allyltrimethylsilane. Direct nucleophilic allylation of alcohol with allyltrimethylsilane proceeds in considerably good yield in the presence of catalytic amount of (0.5 mol %) PMA at room temperature. Copyright © 2009 John Wiley & Sons, Ltd.
Antibacterial, spectral and thermal aspects of drug based‐Cu(II) mixed ligand complexes
Authors: Kharadi G. J. , Patel K. D.
Published: July 2009

The antibiotic agent clioquinol is well known for its drug design and coordinating ability towards metal ions. Copper(II) mixed‐ligand complexes of clioquinol with various uninegative bidentate ligands were prepared. The structure of the synthesized complexes was characterized using elemental analyses, infrared spectra, 1H‐NMR spectra, electronic spectra, magnetic measurements, FAB mass spectrum and thermo gravimetric analyses. The kinetic parameters such as order of reaction (n) and the energy of activation (Ea) are reported using the Freeman–Carroll method. The pre‐exponential factor (A), the activation entropy (ΔS#), the activation enthalpy (ΔH#) and the free energy of activation (ΔG#) were calculated. Complexes were also screened for their in vitro antibacterial activity against a range of Gram‐positive and Gram‐negative bacteria in order to set the precursors for anti‐tumourigenic agent. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and characterization of a new conducting polymer based on 4‐(2,5‐di‐2‐thiophen‐2‐yl‐pyrrol‐1‐yl)‐phthalonitrile
Authors: Yavuz Arzu , Bezgin Buket , Önal Ahmet M.
Published: July 2009

A new conducting polymer was synthesized by electrochemical polymerization of 4‐(2,5‐di‐2‐thiophen‐2‐yl‐pyrrol‐1‐yl)‐phthalonitrile (SNS‐PN). Electrochemical polymerization of SNS‐PN was performed in acetonitrile/0.2M LiClO4 solvent/electrolyte couple. Characterizations of the resulting polymer P(SNS‐PN) were carried out by cyclic voltammetry, UV–vis, and Fourier transform infrared (FTIR) spectroscopic techniques. Spectroelectrochemical studies revealed that P(SNS‐PN) has an electronic band gap of 2.45 eV and exhibits electrochromic behavior. The switching ability of polymer was also monitored and the percentage transmittance change (ΔT%) was found as 24%. It is also found that P(SNS‐PN) is fluorescent and its fluorescence intensity enhances in the presence of cations. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and conductive properties of polycaprolactone‐grafted carbon black nanocomposites
Authors: Cheng Jianguo , Wang Li , Huo Jia , Yu Haojie , Yang Qiang , Deng Libo
Published: July 2009

Polycaprolactone‐grafted carbon black (CB‐g‐PCL) nanocomposites were prepared by surface‐initiated ring‐opening polymerization of ε‐caprolactone on the surface of CB. Thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), atomic force microscope (AFM), X‐ray diffraction (XRD), and polarizing optical microscope (POM) method were employed to characterize the resultant CB‐g‐PCL. The effect of temperature on resistivity of polycaprolactone‐grafted CB (CB‐g‐PCL) nanocomposites was investigated and compared with that of mixture of CB and PCL. It was found that CB‐g‐PCL nanocomposites exhibited positive temperature coefficient (PTC) phenomena between 48 and 51°C, and negative temperature coefficient (NTC) phenomena and between 51 and 54°C. The prepared CB‐g‐PCL nanocomposites have the potential to be temperature‐dependent switch materials. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation, characterization, and surface energetics of hydroxypropyl cellulose/polyethylenimine blends
Authors: Şengül Gamze , Demirci Serkan , Caykara Tuncer
Published: July 2009

Blend films composed of hydroxypropyl cellulose (HPC) and polyethyleneimine (PEI) were prepared by solution casting method. The structure and mechanical properties of the blend films were analyzed by attenuated total reflectance Fourier transform infrared (ATR‐FTIR) spectroscopy and tensile strength tests. The ATR‐FTIR results indicated that there is a 5 cm−1 band shift to higher wave number due to the formation of hydrogen bonding between HPC and PEI components. The mechanical properties of the blends, such as breaking stress, elongation at break, and Young modulus were greatly affected with increase of PEI component. The contact angles of water, ethylene glycol, formamide, and diiodomethane drops were measured on the blend films. The contact‐angle results were evaluated in terms of surface free energy components using van Oss‐Good methodology. It was shown that the surface free energy components of HPC and its blends did not differ so much with the composition. However, the apolar Lifshitz‐van der Waals component ($\gamma^{\rm LW}_{S}$) values are higher than those of the Lewis acid–base interactions component ($\gamma^{\rm AB}_{S}$) values. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Electrospinning of poly(vinyl pyrrolidone): Effects of solvents on electrospinnability for the fabrication of poly(p‐phenylene vinylene) and TiO2 nanofibers
Authors: Chuangchote Surawut , Sagawa Takashi , Yoshikawa Susumu
Published: July 2009

Seven different solvents (methanol, ethanol, 2‐propanol, 1,2‐dichloroethane, water, chloroform, and dichloromethane) were used to prepare electrospun poly(vinyl pyrrolidone) (PVP) fibers. The dielectric constant, viscosity, and surface tension of the solvents essentially affected the electrospinnability, morphological appearance, and size of the as‐spun fibers. Small and uniform as‐spun fibers could be fabricated from PVP solutions in solvents with a significantly high dielectric constant, low surface tension, and low viscosity. In three alcohol solutions (e.g., methanol, ethanol, and 2‐propanol), the diameters of as‐spun PVP fibers decreased with the dielectric constant, dipole moment, and density of the solvents increasing and with the viscosity of the solvents decreasing. Among these solvents, methanol was the best solvent, providing fibers with an optimal morphological appearance and a small fiber diameter. Mixing an unspinnable solvent with a solvent with a high dielectric constant, low surface tension, and low viscosity could increase the electrospinnability of the solution. The effects of solution properties and spinning conditions on the morphological appearance and diameter of electrospun PVP fibers were also carefully investigated. Under all investigated conditions for the electrospinning of a PVP solution in ethanol, the average diameters of the as‐spun fibers ranged from 200 nm to 1.5 μm. Well‐aligned PVP fibers were also produced with a rotating‐drum collector technique. Lastly, PVP was used in the fabrication of poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylene‐vinylene] and TiO2 fibers by acting as a polymer carrier or guide. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Ultrasonic characterization of the crystallization behavior of poly(ethylene terephthalate)
Authors: Zhao Lijuan , Sun Zhigang , Tatibouët Jacques , Guo Shaoyun
Published: July 2009

On the basis of the previous observations that the ultrasonic signals are sensitive to the crystallization of polymers (Tatibouet and Piché, Polymer 1991, 32, 3147), we have expanded our efforts to study the detail relationship between the ultrasonic signals and crystallization process in this work. The nonisothermal and isothermal crystallization of virgin poly(ethylene terephthalate) (PET) and PET samples after degradation were studied by using a specially designed pressure‐volume‐temperature (PVT) device, with which an ultrasonic detector was combined. The results showed that the evolution of the ultrasonic signals not only can be used to probe the crystallization process but also can qualitatively characterize the crystallization rate, crystallinity, crystallite size, and amorphous. DSC measurement was used to verify such results. Ultrasonic signals could be as a complementary tool to polymer chain movement and well be applied to characterize the crystallization behavior. Furthermore, the ultrasonic measurement has the potential use to characterize crystallization of products in‐line during processing (i.e., injection molding, micromoulding). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Spectroscopic investigation of iron salts doped polyaniline
Authors: Vinodh Kumar Selvam , Mukherjee Samrat , Krishna Jakkan Bala Murli , Das Dipankar , Saha Abhijit
Published: July 2009

Iron salts have been doped into emeraldine base (EB) successfully using a chemical route. Both FeCl3 and FeSO4 were doped separately into EB in acetonitrile with metal ion and tetramer in the ratio of 4 : 1. The doped samples were characterized by UV‐vis absorption, Mössbauer and fourier transform infrared (FTIR) spectroscopy. UV‐vis spectra showed a suppression of the characteristic band of EB at 660 nm with an extended absorption towards the infrared regions for both the doped samples. FeSO4 showed electronic absorption behavior similar to the features of acid doped EB. Mössbauer spectroscopy confirmed the presence of single oxidation and high spin states of Fe(III) and Fe(II) in the respective doped polymers. No signature of Fe2+ was observed in the Fe3+ doped EB from the Mössbauer spectrum. FTIR spectroscopy showed a shift towards the lower wave number for the iron salts doped EB as compared to the pristine polymer. An increase in the intensity of the band at 1140 cm−1 is observed, which corresponds to the electronic like absorption confirming the doping of EB. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
In situ compatibilization between polystyrene‐grafted nano‐sized TiO2 and polypropylene with Friedel‐Crafts catalyst
Authors: Xu Lixin , Yang Mujie
Published: July 2009

The application of Friedel‐Crafts (FC) alkylation reaction to the in situ compatibilization between polystyrene‐grafted nano‐sized TiO2 (PS‐grafted TiO2) and polypropylene (PP) was assessed. The PS‐grafted TiO2 was first prepared via dispersion polymerization of styrene (St) using 3‐(trimethoxysilyl) propyl methacrylate treated nano‐sized TiO2 (MPS‐treated TiO2) as cores, and then dispersed within PP by melt blending with different contents of FC catalyst, AlCl3/St, to give PP/PS‐grafted TiO2 nanocomposites. The dispersion of PS‐grafted TiO2 in PP and interfacial adhesion of PP/PS‐grafted TiO2 nanocomposites were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. The results indicated that the dispersion of PS‐grafted TiO2 in PP could be improved, with an enhancement of interfacial adhesion between TiO2 and PP, by introducing FC catalyst with adequate concentration, which led to a better thermal stability and resistance to ultraviolet (UV) aging of PP/PS‐grafted TiO2 nanocomposites. The effect of FC catalyst on the compatibilization between the PS‐grafted TiO2 and PP was discussed based on FC alkylation reaction mechanism. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and characterization of functionalized acrylic‐acrylamide‐based superabsorbent gels
Authors: Zhou Weili , Zhang Yuan , Jin Kemo , Qiu Xiaoyun , Ren Xueqin , Hu Shuwen , Zhang Fusuo
Published: July 2009

We have synthesized series of superabsorbent polymers (SAPs) by solution free radical polymerization of acrylic acid (AA), acrylamide (AM) with different functional monomers (FM). Three functional monomers including zwitterionic monomer [3‐(methacryloylamino) propyl] dimethyl (3‐sulfopropyl) ammonium (MPDSA), cationic monomer (3‐acrylamidopropyl) trimethylammonium chloride (APTAC) and anionic monomer 2‐acrylamidoglycolic acid monohydrate (AGAM) were selected to provide different charged groups on the superabsorbents. The effect of reaction parameters, such as degree of neutralization, content of initiator and crosslinker on the swelling capacity were assessed. The water absorbency of the superabsorbent were characterized in the distilled water, 0.9 wt % NaCl solution and the mixed solution containing 60 mg L−1 CaCl2 and 30 mg L−1 MgCl2, respectively. In addition, the swelling rate and water retention capacity in the soil were also investigated. Finally, the mechanism of different absorbency induced by the variety kinds of functional monomers was studied by XPS and FTIR, and tentative interpretation was presented as well. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Analysis and evaluation of the ionic interaction of the novel soft contact lenses using the zwitterionic polymer gel
Authors: Yamazaki Yoshiko , Matsunaga Toru , Ichinokawa Aya , Fujishiro Yoko , Saito Emi , Sato Takao
Published: July 2009

In the zwitterionic polymer gel which has cationic and anionic groups inside, it forms a complex to producing stability by adding thermal energy. We reported the behavior induced by the ionic interaction of them and the impact that a nonionic surfactant could exert on the complex formation. We had heating experiments of the zwitterionic polymer gel in PBS with a nonionic surfactant added. We analyzed DSC and measured the diameter, stress and flexure of heated the gel. As the result, it has been demonstrated that formation of strong ionic interactions inside the gel can be achieved by heating them in a solution containing the nonionic surfactant. It has been also demonstrated that the ratio of bound water is increased within the gel, promising an enhanced strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and characterization of polyurethane/Mg‐Al layered double hydroxide nanocomposites
Authors: Kotal M. , Kuila T. , Srivastava S. K. , Bhowmick A. K.
Published: July 2009

Layered double hydroxide (LDH) is a new type of nanofiller, which improves the physicochemical properties of the polymer matrix. In this study, 1, 3, 5, and 8 wt % of dodecyl sulfate‐intercalated LDH (DS‐LDH) has been used as nanofiller to prepare a series of thermoplastic polyurethane (PU) nanocomposites by solution intercalation method. PU/DS‐LDH composites so formed have been characterized by X‐ray diffraction and transmission electron microscopy analysis which show that the DS‐LDH layers are exfoliated at lower filler (1 and 3 wt %) loading followed by intercalation at higher filler (8 wt %) loading. Mechanical properties of the nanocomposite with 3 wt % of DS‐LDH content shows 67% improvement in tensile strength compared to pristine PU, which has been correlated in terms of fracture behavior of the nanocomposites using scanning electron microscope analysis. Thermogravimetric analysis shows that the thermal stability of the nanocomposite with 3 wt % DS‐LDH content is ≈ 29°C higher than neat PU. Limiting oxygen index of the nanocomposites is also improved from 19 to 23% in neat PU and PU/8 wt% DS‐LDH nanocomposites, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
3D study on the effect of process parameters on the cooling of polymer by injection molding
Authors: Hassan Hamdy , Regnier Nicolas , Pujos Cyril , Defaye Guy
Published: July 2009

Plastic injection molding (PIM) is well known as a manufacturing process to produce products with various shapes and complex geometry at low cost. Determining optimal settings of process parameters critically influence productivity, quality, and cost of production in the PIM industry. To study the effect of the process parameters on the cooling of the polymer during injection molding, a full three‐dimensional time‐dependent injection molding analysis was carried out. The studied configuration consists of a mold having cuboids‐shaped cavity with two different thicknesses and six cooling channels. A numerical model by finite volume was used for the solution of the physical model. A validation of the numerical model was presented. The effect of different process parameters (inlet coolant temperature, inlet coolant flow rate, injection temperature, and filling time) on the cooling process was considered. The results indicate that the filling time has a great effect on the solidification of the product during the filling stage. They also show that low coolant flow rate increases the heterogeneity of the temperature distribution through the product. The process parameter realizing minimum cooling time not necessary achieves optimum product quality and the complete filling of the cavity by the polymer material. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effects of glycerol and ethylene–acrylic acid on composition optimization of PVOH/starch‐blended biodegradable resin using response surface methodology
Authors: Li Yang‐Xiu , Peng Jinchyau , Lui Wai‐Bun , Lin Jenshinn
Published: July 2009

Response surface methodology was used to analyze the effect of glycerol (X1) and ethylene–acrylic acid (EAA) level (X2) on the objective (water solubility index (WSI), water absorption index (WAI), and tensile strength) attributes of a poly(vinyl alcohol) (PVOH)/starch‐blended plastic resin. A rotable central composite design was used to develop models for the objective responses. The experiments were run with different barrel temperatures, such as zone 1: 100°C, zone 2: 100°C, zone 3: 105°C, and zone 4: 105°C, respectively, with a feed rate of 20 g/min and screw speed of 25 rpm. Responses were most affected by changes in glycerol level (X1) and to a lesser extent by EAA level (X2). Individual contour plots of the different responses were overlaid, and regions meeting the optimum WSI of 6.10%, WAI of 5.57 g gel/g dry wt, and tensile strength of 62.14 MPa were identified at the glycerol level of 72.41 mL and the EAA level of 36.03 g, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Chitosan‐comb‐graft‐polyethylene glycol monomethacrylate—Synthesis, characterization, and evaluation as a biomaterial for hemodialysis applications
Authors: Radhakumary C. , Nair Prabha D. , Nair C. P. Reghunadhan , Mathew Suresh
Published: July 2009

Chitosan was reacted with “Polyethylene glycol monomethacrylate” (PEGm) using a redox initiation method. Different compositions were prepared by varying the relative amount of PEGm in the feed. A maximum of 88% yield with 320% grafting could be achieved. The graft copolymerization was confirmed by FTIR, thermal, and XRD studies. Higher graft % could be achieved as the monomer used is a macro monomer of PEG and the resultant graft is a comb‐like polymer. Grafting with PEGm did not affect the thermal stability of chitosan film significantly, however, it resulted in a marginal increase in the tensile strength of the films in the dry state. The products showed much improved swelling at pH 7.4 and pH 1.98 compared to the virgin chitosan. The preliminary biocompatibility evaluation showed that the materials are blood compatible and non‐cytotoxic. Though the permeability to low molecular weight solutes like creatinine and glucose was equal to or better than commercial cellulose membranes, the copolymer films expressed comparatively less permeability to these solutes initially, due to the crystalline domains of PEO grafts that impede the transport. On exposure in the medium, this effect is nullified culminating in better permeability. The crystallization of PEG grafts was very helpful in preventing the permeation of the high molecular weight solute albumin, the leakage of which above a certain limit is dangerous to the patient. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Optimized processing conditions for the preparation of dynamically vulcanized EPDM/PP thermoplastic elastomers containing PP resins of various melt indexes
Authors: Yeh Jen‐Taut , Lin Shui‐Chuan
Published: July 2009

We have investigated the mechanical and morphological properties of un‐vulcanized and dynamically vulcanized ethylene propylene diene terpolymer/polypropylene (EPDM/PP) thermoplastic elastomers prepared under various processing conditions and possessing various compositions. After melt‐blending EPDM and PP resins twice in a twin‐screw extruder, the values of tensile strength (σf) of the un‐vulcanized EPDM/PP samples were at most equal to that of the pure EPDM specimen, but were much lower than those of the pure PP specimens. The elongations at break (εf) of the un‐vulcanized EPDM/PP samples were, however, dramatically higher than those of their respective virgin PP resins, and they improved significantly upon increasing the shear viscosity (ηs) of the PP resins. The tensile properties of the dynamically vulcanized EPDM/PP samples were significantly better than those of the corresponding un‐vulcanized EPDM/PP specimens. Similar to the behavior of the un‐vulcanized EPDM/PP specimens, the tensile properties of the dynamically vulcanized EPDM/PP specimens were optimized when prepared at a screw rate of 115 rpm. Morphological analysis revealed that the un‐vulcanized and dynamically vulcanized EPDM/PP specimens both featured many EPDM domains finely dispersed in continuous PP matrices. Such domains were present on the surfaces of the dynamically vulcanized EPDM/PP specimens; the relative sizes of the vulcanized EPDM domains were minimized when the vulcanized EPDM/PP specimens were prepared at the optimal screw rate (115 rpm). In fact, under these conditions, the average sizes of the vulcanized EPDM domains decreased upon increasing the values of ηs of the PP resins used to prepare the vulcanized EPDM/PP specimens. To understand these interesting tensile and morphological properties of the un‐vulcanized and dynamically vulcanized EPDM/PP specimens, we measured the rheological properties of the base polymers and performed energy‐dispersive x‐ray (EDX) analyzes of the compositions of the un‐vulcanized and dynamically vulcanized EPDM/PP specimens. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Starch–acrylics graft copolymers and blends: Synthesis, characterization, and applications as matrix for drug delivery
Authors: Shaikh M. M. , Lonikar S. V.
Published: July 2009

A series of acrylic monomers–starch graft copolymers were prepared by ceric ion initiation method by varying the amount of monomers. These graft copolymers were characterized by IR and 13C‐NMR spectroscopy. It was seen that as the concentration of monomer [acrylic acid (AA), methacrylic acid (MA), and methyl methacrylate (MMA)] increased the percent add‐on increased in all the graft copolymers, whereas grafting efficiency increased initially but showed a slight decrease with further increase in the monomer concentration (except for MMA). The release rate of paracetamol as a model drug from graft copolymers as well as their blends was studied at two different pH, 1.2 and 7.4, spectrophotometrically. The release of paracetamol in phosphate buffer solution at pH 1.2 was insignificant in the first 3 h for St‐g‐PAA‐ and St‐g‐PMA‐graft copolymers, which was attributed to the matrix compaction and stabilization through hydrogen bonding at lower pH. At pH 7.4, the release rate was seen to decrease with increase in add‐on. The tablet containing poly(methyl methacrylate) (PMMA) did not disintegrate at the end of 30–32 h, which may be attributed to the hydrophobic nature of PMMA. These results indicate that the graft copolymers may be useful to overcome the harsh environment of the stomach and can be used as excipients in colon‐targeting matrices. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation of poly(styrene‐co‐hexylacrylate)/cellulose whiskers nanocomposites via miniemulsion polymerization
Authors: Elmabrouk Aymen Ben , Wim Thielemans , Dufresne Alain , Boufi Sami
Published: July 2009

A stable aqueous nanocomposite dispersion containing cellulose whiskers and a poly(styrene‐co‐hexylacrylate) matrix was prepared via miniemulsion polymerization. We were able to prepare a stable dispersion with a 20 wt % solid content and a cellulose whiskers content ranging from 1 up to 5 wt % based on polymer content. To avoid particle agglomeration leading to coagulum formation, the addition of a low amount of reactive silane, i.e., methacryloxypropyl triethoxysilane revealed to efficiently stabilize the dispersion. The nanocomposite dispersion was characterized using dynamic light scattering, transmission electron microscopy, and atomic force microscopy. Films obtained by casting followed by water evaporation and particle coalescence were analyzed by differential scanning calorimetry, dynamic mechanical analysis, and tensile testing. At 5 wt % whiskers loading, an enhancement by 500% of the storage modulus above the glass transition was determined. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and analysis of a flexible curing agent for epoxy resin
Authors: Yang Y. , Chen Gong , Liew K. M.
Published: July 2009

A kind of novel aromatic amine bis(4‐nonyl‐2,5‐diamine‐penoxyl)alkylate (RAn) as curing agents for epoxy resins were prepared through three steps of reactions using nonyl phenol and dibromoalkylate as materials. Dynamic mechanical analysis (DMA) indicated that the secondary relaxation for the resins cured by RAn were generated by the nonyls in RAn molecules when temperature was below −50°C. Comparing with other reference resins, the enhancement for toughness of RAn cured‐resins were at least 15%, which were contributed by such secondary relaxation. Furthermore, stiffness of the networks and thermal properties of the resins were not influent by the flexible groups (nonyl) in RAn after curing, since the groups were located only in the branched chains of the networks. The mechanical and thermal properties of the new material have been significantly enhanced. The relevant method and procedure developed through this research have been granted Chinese patent recently (Yang and Gong, Chin. Pat. CN1978483A, 2007). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
A suspension of spheres in a dilute polymer solution
Authors: Grisafi S.
Published: July 2009

The Hookean dumbbell model of a macromolecule predicts non‐uniform density and pressure fields surrounding a sphere buoyant in a dilute polymer solution when the size of the sphere is of the same order of magnitude as the size of the macromolecules. Using this prediction, the root mean square separation distance of a suspension of spheres buoyant within a dilute polymer solution is found to be inversely proportional to both the square of the radius of a sphere and the density of the polymer solution. The phase space distribution function for an ensemble of spheres immersed at equilibrium within a dilute polymer solution is found and used to define the magnitude of the ensemble average peculiar acceleration of the spheres. The peculiar acceleration results from changes in direction of the peculiar velocity. It is found to be directly proportional to the temperature, polymer density, and square of the radius of a sphere and inversely proportional to the mass of a sphere. The self‐ diffusivity of the particles varies directly with the square root of the temperature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Value‐added derivatives of soda lignin Alfa grass (Stipa tenacissima). II. Uses as lubricants in plastic processing
Authors: Nadji H. , Rodrigue D. , Benaboura A. , Bédard Y. , Stevanovic T. , Riedl B.
Published: July 2009

Esparto (Stipa tenacissima) grass, also called Alfa is the raw material for the manufacture of paper pulp in North Africa. To add value to one of its processing by‐products, we aimed to develop lubricants from modified Soda‐Lignin (SL), which could eventually compete with industrial lubricants such as zinc stearates. Linear low density polyethylene mixed formulations prepared with zinc stearate and each modified lignin was studied by rheological tests using a rotational parallel plate system to investigate the effects of such esterified SL additives. One type, made up of SL esterified with 100% stearic anhydride (W/W) was found to promote excellent external lubrication. The same result was confirmed by contact angle and thermal analysis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009