bluuebunny/crossref_metadata_2025 huggingface dataset:
Dendrocalamus strictus((Roxb.) Nees): A Suitable Host for the Maintenance and Propagation of AM Fungi under Temperate Conditions
Authors: Singh Shipra , Kumar Ajay , Pandey Anita , Palni Lok Man S.
Published: April 2012

Dendrocalamus strictus((Roxb.) Nees) was tested as a perennial host plant for propagation of an arbuscular mycorrhizal (AM) fungal consortium, initially isolated from rhizosphere of tea plants growing in the colder regions. The host performance in terms of colonization and spore production was compared with two annual hosts. The mycorrhizal dependency and growth enhancement potential were analyzed to test the suitability ofD. strictusas a host plant. After 90 days of growth, 77.2% roots ofD. strictuswere found to be colonized by AM fungi with a spore count of 7 per g soil. AM fungal colonization and spore density values were lower in case of the host plants tested. Growth ofD. strictusplants was found to be enhanced, in terms of all studied parameters; significant increases were recorded in shoot length as well as fresh and dry weight of shoots, a part of commercial importance. Similarly, P content, protein concentration, chlorophyll a and chlorophyll b contents were found to increase significantly. These data suggest thatD. strictuscan be used for the multiplication of AM fungi, isolated originally from the rhizosphere of tea; simultaneously, higher shoot biomass can provide additional economic benefit, using this environment friendly technology.
Decentralization and School Management in Namibia: The Ideologies of Education Bureaucrats in Implementing Government Policies
Authors: Pomuti Hertha , Weber Everard
Published: April 2012

This paper defines ideology as the belief systems, attitudes, views, and mindsets of educationists which inform their work. It examines the ideologies of school inspectors, principals, and teachers in the implementation of decentralized, cluster-based educational change in Namibia (see Pomuti 2009). Data were collected in three diverse school clusters. Data analyses resulted in the ideologies of the educationists being characterised as authoritarian, bureaucratic, and managerial. The paper argues that while the postapartheid Namibian government has changed the governance structures in education, it has not succeeded in changing the mindsets and actions of important reform implementers. These have more in common with the apartheid system than with the participatory, collaborative, and democratic ideas upon which cluster-based school management in the new Namibia is based.
Structural and Thermophysical Properties of Cadmium Oxide
Authors: Bhardwaj Purvee
Published: April 2012

We have studied the structural and thermophysical properties of cadmium oxide (CdO), using the Three-Body Potential (TBP) model. Phase transition pressures are associated with a sudden collapse in volume. The phase transition pressures and related volume collapses obtained from this model show a generally good agreement with available experimental others data. The thermophysical properties like molecular force constant, Debye temperature, and so forth, of CdO are also reported.
Black Wattle Tannin As Steel Corrosion Inhibitor
Authors: Peres Rafael Silveira , Cassel Eduardo , Azambuja Denise Schermann
Published: April 2012

In order to reduce the environmental impacts caused by chemical substances harmful to the environment and human health, the black wattle tannin can be used as an environmentally friendly corrosion inhibitor in acid and near neutral media. This paper provides information on the application of black wattle tannin as an inhibitor against the corrosion of carbon steel. The inhibition was evaluated using potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) at room temperature in aerated 0.1 mol L−1 Na2SO4 (pH 6.0 and 2.5). The black wattle tannin when used as a corrosion inhibitor is more effective at acidic pH, its efficiency being dependent on its concentration. At the higher pH value (pH 6.0), a blue-black film (ferric tannate) with a short-term protection against corrosion was formed in aerated aqueous solution. At pH 2.5, this blue-black film was not observed.
Emergency Room Admission of On-Duty Police at a Swiss University Hospital
Authors: Exadaktylos Aristomenis K. , Businger Adrian , Aeschbacher Gina , Martinolli Luca , Zimmermann Heinz
Published: April 2012

Background. Police and law enforcement officers may face physical violence and multiple occupational hazards in the line of duty. There is no nationwide statistical reporting of police officers’ injuries in Switzerland. The aim of this study was to describe the epidemiological features of emergency room admissions of on-duty police officers. Methods. The retrospective analysis was based on the prospective database of the Emergency Department of Bern University Hospital. Fifty-seven (57) police officers presenting to our department were included and analysed. Results. Minor blunt trauma (32/57) associated with extremity trauma was the leading cause of admission to our emergency department. 16 body fluid born exposures with a possible risk of viral transmission were reported, with 12/16 cases during summer; serological testing for HBV, HCV, and HIV was negative in all cases. No police death was reported. Conclusions. Police officers are exposed to occupational hazards. In comparison to other countries the number of severely injured or killed officers is very low. In the light of the daily reports in the lay media about assaulted police officers, it may be assumed that the majority of injured police officers were treated by general practitioners outside the hospital or treated by themselves. An adequate injury prevention strategy is desirable, combined with more meticulous nationwide reporting of police officers’ injuries.
The Basics of Coverage, Coding, and Reimbursement
Authors: Wanerman Robert
Published: April 2012

The process of commercializing a new item or service in the U.S. health care market involves three distinct but necessary components: coverage, coding, and reimbursement.Â  This article provides an overview of these processes and the challenges in successfully navigating the course and spotting the particular issues for individual items and services.
Children and Terror Casualties Receive Preference in ICU Admissions
Authors: Peleg Kobi , Rozenfeld Michael , Dolev Eran ,   the Israel Trauma Group
Published: April 2012

Objective: Trauma casualties caused by terror-related events and children injured as a result of trauma may be given preference in hospital emergency departments (EDs) due to their perceived importance. We investigated whether there are differences in the treatment and hospitalization of terror-related casualties compared to other types of injury events and between children and adults injured in terror-related events.

Methods: Retrospective study of 121 608 trauma patients from the Israel Trauma Registry during the period of October 2000-December 2005. Of the 10 hospitals included in the registry, 6 were level I trauma centers and 4 were regional trauma centers. Patients who were hospitalized or died in the ED or were transferred between hospitals were included in the registry.

Results: All analyses were controlled for Injury Severity Score (ISS). All patients with ISS 1-24 terror casualties had the highest frequency of intensive care unit (ICU) admissions when compared with patients after road traffic accidents (RTA) and other trauma. Among patients with terror-related casualties, children were admitted to ICU disproportionally to the severity of their injury. Logistic regression adjusted for injury severity and trauma type showed that both terror casualties and children have a higher probability of being admitted to the ICU.

Conclusions: Injured children are admitted to ICU more often than other age groups. Also, terror-related casualties are more frequently admitted to the ICU compared to those from other types of injury events. These differences were not directly related to a higher proportion of severe injuries among the preferred groups.

(Disaster Med Public Health Preparedness. 2012;6:14–19)
The New Normal: Twelve Months of Resiliency and Recovery in Christchurch
Authors: McColl Graeme J. , Burkle Frederick M.
Published: April 2012

The series of earthquakes and aftershocks that have hit Christchurch, New Zealand, for more than one year has been severe and sustained, resulting in major damage to homes, buildings, essential services, and resources in water, sewerage, food, access to health care, energy for heating and cooling, and unprecedented challenges to resiliency. Large swathes of destroyed buildings, land damage, and liquefaction have made rebuilding impossible for many. Populations have moved or report that they either wish to or plan to do so. For those who remain, a ”new normal” mindset has taken hold and serves as an objective measure for the process that defines daily life and future decisions. The new normal serves as an uncomfortable but realistic guideline by which further resiliency can be measured. A number of factors have led to the development of the new normal state for the Christchurch earthquake survivors.

(Disaster Med Public Health Preparedness. 2012;6:33-43)
Natural convection in a vertical porous cavity filled with a non‐newtonian binary fluid
Authors: Khelifa Nabil Ben , Alloui Zineddine , Beji Hassen , Vasseur Patrick
Published: April 2012

Numerical and analytical study of natural convection in a vertical porous cavity filled with a non‐Newtonian binary fluid is presented. The density variation is taken into account by the Boussinesq approximation. A power‐law model is used to characterize the non‐Newtonian fluid behavior. Neumann boundary conditions for temperature are applied to the vertical walls of the enclosure, while the two horizontal ones are assumed impermeable and insulated. Both double‐diffusive convection (a = 0) and Soret‐induced convection (a = 1) are considered. Scale analysis is presented for the two extreme cases of heat‐driven and solute‐driven natural convection. For convection in a thin vertical layer (A ≫ 1), a semianalytical solution for the stream function, temperature, and solute fields, Nusselt and Sherwood numbers are obtained using a parallel flow approximation in the core region of the cavity and an integral form of the energy and constituent equations. Numerical results of the full governing equations show the effects of the governing parameters, namely the thermal Rayleigh number, RT, the Lewis number, Le, the buoyancy ratio, φ, the power‐law index, n, and the integer number a. A good agreement between the analytical predictions and the numerical simulations is obtained. © 2012 American Institute of Chemical Engineers AIChE J, 58: 1704–1716, 2012
A support vector clustering‐based probabilistic method for unsupervised fault detection and classification of complex chemical processes using unlabeled data
Authors: Yu Jie
Published: April 2012

A new support vector clustering (SVC)‐based probabilistic approach is developed for unsupervised chemical process monitoring and fault classification in this article. The spherical centers and radii of different clusters corresponding to normal and various kinds of faulty operations are estimated in the kernel feature space. Then the geometric distance of the monitored samples to different cluster centers and boundary support vectors are computed so that the distance–ratio–based probabilistic‐like index can be further defined. Thus, the most probable clusters can be assigned to the monitored samples for fault detection and classification. The proposed SVC monitoring approach is applied to two test scenarios in the Tennessee Eastman Chemical process and its results are compared to those of the conventional K‐nearest neighbor Fisher discriminant analysis (KNN‐FDA) and K‐nearest neighbor support vector machine (KNN‐SVM) methods. The result comparison demonstrates the superiority of the SVC‐based probabilistic approach over the traditional KNN‐FDA and KNN‐SVM methods in terms of fault detection and classification accuracies. © 2012 American Institute of Chemical Engineers AIChE J, 59: 407–419, 2013
Alagille syndrome in a Vietnamese cohort: Mutation analysis and assessment of facial features
Authors: Lin Henry C. , Le Hoang Phuc , Hutchinson Anne , Chao Grace , Gerfen Jennifer , Loomes Kathleen M. , Krantz Ian , Kamath Binita M. , Spinner Nancy B.
Published: April 2012

Alagille syndrome (ALGS, OMIM #118450) is an autosomal dominant disorder that affects multiple organ systems including the liver, heart, eyes, vertebrae, and face. ALGS is caused by mutations in one of two genes in the Notch Signaling Pathway, Jagged1 (JAG1) or NOTCH2. In this study, analysis of 21 Vietnamese ALGS individuals led to the identification of 19 different mutations (18 JAG1 and 1 NOTCH2), 17 of which are novel, including the third reported NOTCH2 mutation in Alagille Syndrome. The spectrum of JAG1 mutations in the Vietnamese patients is similar to that previously reported, including nine frameshift, three missense, two splice site, one nonsense, two whole gene, and one partial gene deletion. The missense mutations are all likely to be disease causing, as two are loss of cysteines (C22R and C78G) and the third creates a cryptic splice site in exon 9 (G386R). No correlation between genotype and phenotype was observed. Assessment of clinical phenotype revealed that skeletal manifestations occur with a higher frequency than in previously reported Alagille cohorts. Facial features were difficult to assess and a Vietnamese pediatric gastroenterologist was only able to identify the facial phenotype in 61% of the cohort. To assess the agreement among North American dysmorphologists at detecting the presence of ALGS facial features in the Vietnamese patients, 37 clinical dysmorphologists evaluated a photographic panel of 20 Vietnamese children with and without ALGS. The dysmorphologists were unable to identify the individuals with ALGS in the majority of cases, suggesting that evaluation of facial features should not be used in the diagnosis of ALGS in this population. This is the first report of mutations and phenotypic spectrum of ALGS in a Vietnamese population. © 2012 Wiley Periodicals, Inc.
KRAS gene mutations in Noonan syndrome familial cases cluster in the vicinity of the switch II region of the G‐domain: Report of another family with metopic craniosynostosis
Authors: Brasil Amanda S. , Malaquias Alexsandra C. , Kim Chong A. , Krieger José Eduardo , Jorge Alexander A.L. , Pereira Alexandre C. , Bertola Débora R.
Published: April 2012

Noonan syndrome (NS) and Noonan‐related disorders [cardio‐facio‐cutaneous (CFC), Costello, Noonan syndrome with multiple lentigines (NS‐ML), and neurofibromatosis‐Noonan syndromes (NFNS)] are a group of developmental disorders caused by mutations in genes of the RAS/MAPK pathway. Mutations in the KRAS gene account for only a small proportion of affected Noonan and CFC syndrome patients that present an intermediate phenotype between these two syndromes, with more frequent and severe intellectual disability in NS and less ectodermal involvement in CFC syndrome, as well as atypical clinical findings such as craniosynostosis. Recently, the first familial case with a novel KRAS mutation was described. We report on a second vertical transmission (a mother and two siblings) with a novel mutation (p.M72L), in which the proband has trigonocephaly and the affected mother and sister, prominent ectodermal involvement. Metopic suture involvement has not been described before, expanding the main different cranial sutures which can be affected in NS and KRAS gene mutations. The gene alteration found in the studied family is in close proximity to the one reported in the other familial case (close to the switch II region of the G‐domain), suggesting that this specific region of the gene could have less severe effects on intellectual ability than the other KRAS gene mutations found in NS patients and be less likely to hamper reproductive fitness. © 2012 Wiley Periodicals, Inc.
Consanguinity and the risk of congenital heart disease
Authors: Shieh Joseph T.C. , Bittles Alan H. , Hudgins Louanne
Published: April 2012

Consanguineous unions have been associated with an increased susceptibility to various forms of inherited disease. Although consanguinity is known to contribute to recessive diseases, the potential role of consanguinity in certain common birth defects is less clear, particularly since the disease pathophysiology may involve genetic and environmental/epigenetic factors. In this study, we ask whether consanguinity affects one of the most common birth defects, congenital heart disease, and identify areas for further research into these birth defects, since consanguinity may now impact health on a near‐global basis. A systematic review of consanguinity in congenital heart disease was performed, focusing on non‐syndromic disease, with the methodologies and results from studies of different ethnic populations compared. The risks for congenital heart disease have been assessed and summarized collectively and by individual lesion. The majority of studies support the view that consanguinity increases the prevalence of congenital heart disease, however, the study designs differed dramatically. Only a few (n = 3) population‐based studies that controlled for potential sociodemographic confounding were identified, and data on individual cardiac lesions were limited by case numbers. Overall the results suggest that the risk for congenital heart disease is increased in consanguineous unions in the studied populations, principally at first‐cousin level and closer, a factor that should be considered in empiric risk estimates in genetic counseling. However, for more precise risk estimates a better understanding of the underlying disease factors is needed. © 2012 Wiley Periodicals, Inc.
Loeys–Dietz syndrome presenting as respiratory distress due to pulmonary artery dilation
Authors: Kuppler Kevin M. , Kirse Daniel J. , Thompson James T. , Haldeman‐Englert Chad R.
Published: April 2012

Loeys–Dietz syndrome (LDS) is an autosomal dominant connective tissue condition with clinical features that may include ocular hypertelorism, cleft palate, craniosynostosis, and vascular dilation and tortuosity. Here we describe a patient with LDS confirmed by genetic analysis (R528H mutation of TGFBR2) who presented at 3 months of age in respiratory distress of unknown origin. In addition to expressing several of the classic findings of LDS, including a novel finding of squamosal suture craniosynostosis, CT angiography revealed aortic dilation at the sinus of valsalva, pulmonary artery dilation that extrinsically compressed the right mainstem bronchus causing bronchomalacia, and an apical herniation of the right lung. This is the first documentation of concomitant airway and pulmonary findings in a patient with LDS. We suggest that (1) vascular abnormalities be considered as a cause of unexplained respiratory distress in a patient with LDS, and (2) pediatric patients exhibiting any of the physical findings listed above be evaluated for LDS with particular attention paid to vascular, airway, and/or pulmonary malformations. © 2012 Wiley Periodicals, Inc.
12p13 rearrangements: 6 Mb deletion responsible for ID/MCA and reciprocal duplication without clinical responsibility
Authors: Madrigal Irene , Martinez Margarita , Rodriguez‐Revenga Laia , Carrió Ana , Milà Montserrat
Published: April 2012

Congenital balanced reciprocal translocations are one of the most frequent structural chromosomal aberrations in the population. We report a familial translocation t(12;22)(p13.3;pter) responsible for intellectual disabilities and congenital anomalies characterized by FISH and array CGH. Two patients carried a der(12)t(12;22)(p13.3;pter), resulting in a 6 Mb 12pter deletion. Patients presented with intellectual disabilities, pre‐ and post‐natal growth retardation, ponderal development delay, global hypotonia, feeding problems and dysmorphic features. Two relatives presented with the reciprocal 12pter duplication, which had no clinical manifestations associated. For this translocation, we propose a mechanism based on a non‐allelic recombination model, in which recombination of direct oriented segmental duplications between non‐homologous chromatids leads to the reciprocal translocation. The characterization of this translocation has been critical for the family. Translocation carriers have a risk of 40% of having offspring carrying unbalanced products. 12p13.3 deletion carriers present with a recognizable syndrome and on the contrary, 12p13.3 duplication carriers present without clinical manifestations. Other published cases of 12p13.3 duplication show that this syndrome has a variable phenotype. It is advisable to delineate the duplication size and to discard other genetic aberrations, in order to give an accurate genetic counseling in patients carrying 12pter duplications. © 2012 Wiley Periodicals, Inc.
No associations found between the genes situated at 6p22.1, HIST1H2BJ, PRSS16, and PGBD1 in Japanese patients diagnosed with schizophrenia
Authors: Kitazawa Maiko , Ohnuma Tohru , Takebayashi Yuto , Shibata Nobuto , Baba Hajime , Ohi Kazutaka , Yasuda Yuka , Nakamura Yukako , Aleksic Branko , Yoshimi Akira , Okochi Tomo , Ikeda Masashi , Naitoh Hiroshi , Hashimoto Ryota , Iwata Nakao , Ozaki Norio , Takeda Masatoshi , Arai Heii
Published: April 2012

Recent GWAS demonstrated an association between candidate genes located at region 6p22.1 and schizophrenia. This region has been reported to house certain candidate SNPs, which may be associated with schizophrenia at HIST1H2BJ, PRSS16, and PGBD1. These genes may presumably be associated with pathophysiology in schizophrenia, namely epigenetics and psychoneuroimmunology. A three‐step study was undertaken to focus on these genes with the following aims: (1) whether these genes may be associated in Japanese patients with schizophrenia by performing a 1st stage case–control study (514 cases and 706 controls) using Japanese tagging SNPs; (2) if the genetic regions of interest for the disease from the 1st stage of analyses were found, re‐sequencing was performed to search for new mutations; (3) finally, a replication study was undertaken to confirm positive findings from the 1st stage were reconfirmed using a larger number of subjects (2,583 cases and 2,903 controls) during a 2nd stage multicenter replication study in Japan. Genotyping was performed using TaqMan PCR method for the selected nine tagging SNPs. Although three SNPs situated at the 3′ side of PGBD1; rs3800324, rs3800327, and rs2142730, and two‐window haplotypes between rs3800327 and rs2142730 showed positive associations with schizophrenia, these associations did not have enough power to sustain significance during the 2nd stage replication study. In addition, re‐sequencing for exons 5 and 6 situated at this region did not express any new mutations for schizophrenia. Taken together these results indicate that the genes HIST1H2BJ, PRSS16, and PGBD1 were not associated with Japanese patients with schizophrenia. © 2012 Wiley Periodicals, Inc.
Association between serotonin transporter gene polymorphism and eating disorders outcome: A 6‐year follow‐up study
Authors: Castellini Giovanni , Ricca Valdo , Lelli Lorenzo , Bagnoli Silvia , Lucenteforte Ersilia , Faravelli Carlo , Sorbi Sandro , Nacmias Benedetta
Published: April 2012

Eating disorder patients show different long‐term outcomes, and trait‐related alterations of serotonergic function, which might be related with the serotonin transporter (5‐HTT) gene. We studied the relationships between 5‐HTTLPR polymorphism, eating specific and general psychopathology and the long‐term outcome of anorexia nervosa (AN) and bulimia nervosa (BN) patients. We evaluated the distribution of the functional 5‐HTTLPR polymorphism in a series of 201 Italian, Caucasian, eating disorder patients (113 with AN and 88 with BN binge/purging (BP subtype) and in 150 Caucasian unrelated controls. Prior to starting an individual cognitive behavior therapy, a clinical assessment was performed by means of the structured clinical interview for DSM‐IV axis I disorders and several self‐report questionnaires. This assessment was repeated at the end of treatment, 3 years after the end of treatment and 3 years after the first follow‐up. Diagnostic changes between AN and BN were frequent (28.3%), and the presence of depressive disorders was associated with a higher rate of diagnostic crossover during the follow‐up period. The S‐allele of the 5‐HTTLPR genotype increases the risk susceptibility for both depressive comorbidity (OR = 4.23; 95% CI, 1.45–12.37) and diagnostic crossover during the follow‐up period in AN patients (OR = 5.04; 95% CI, 1.69–14.98). Logistic regression analyses confirmed these findings, when the interaction between genotype and psychiatric comorbidity as predictors of diagnostic instability in AN patients were taken into account. No significant association was found between 5‐HTTLPR genotype and recovery. The S‐allele of the 5‐HTTLPR genotype increases the risk for depressive disorders comorbidity, and moderates the long‐term outcome of anorectic patients. © 2012 Wiley Periodicals, Inc.
Morphology and thermal and mechanical properties of phosphonium vermiculite filled poly(ethylene terephthalate) composites
Authors: Zeng Xianshen , Cai Deming , Lin Zhidan , Cai Xiang , Zhang Xiuju , Tan Shaozao , Xu Yingbin
Published: April 2012

A series of poly(ethylene terephthalate) (PET)/phosphonium vermiculite (P‐VMT) composites were prepared by a melt‐blending method, and we investigated the morphology and thermal and mechanical properties of the composites. We prepared P‐VMT with quaternary phosphonium salts using the common method followed by a cation‐exchange reaction. X‐ray diffraction showed that the phosphonium surfactants were partially intercalated into the vermiculite layers, The d‐spacing of the PET–clay sample was somewhat less than that of the P‐VMT because some degradation of the surfactant took place during melt processing. Compared with PET, the PET–clay composites had a lower decomposition temperature and showed a 17.4% increase in the tensile strength with a P‐VMT content of 3 wt %. Scanning electron microscopy and transmission electron microscopy demonstrated that P‐VMT had a homogeneous dispersion and good compatibility in the polymer matrix with a low content of additive and indicated that the P‐VMT content of 3 wt % was optimal. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and characterization of novel pyridine‐based polyureas with enhanced solubility and high thermal stability
Authors: Ehsani Sara , Mehdipour‐Ataei Shahram , Mahmoodi Ali
Published: April 2012

The main aim of this study was the preparation of modified polyureas with improved thermal stability and solubility. Accordingly, a series of aromatic/aliphatic pyridine‐based polyureas was synthesized from the reaction of a novel diamine (DA) with different diisocyanates, including 4,4′‐diphenylmethane diisocyanate, toluene diisocyanate, 1,5‐naphthalene diisocyanate, and isophorone diisocyanate, by a solution polymerization route. The DA monomer was prepared via a two‐step reaction. The nucleophilic substitution reaction of oxydianiline with 6‐chloronicotinoylchloride led to the preparation of a diamide dichloro compound, and the subsequent reaction of this compound with 4‐aminophenol resulted in the preparation of the DA. After polymerization, the structural characterization and physical properties of the polymers were examined. The resulting polymers were soluble in common polar aprotic solvents, and they showed improved thermal stabilities in comparison with common polyureas. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of multiple extrusions on the impact properties of polypropylene/clay nanocomposites
Authors: Klitkou R. , Jensen E. A. , Christiansen J. de C.
Published: April 2012

Polypropylene (PP)‐based polymer nanocomposites containing organically modified montmorillonite (OMMT) with and without maleic anhydride grafted PP, were compounded by twin‐screw extrusion. The extrusion process was repeated various numbers of times to increase the extruder residence time (TR) and, through that, the particle dispersion. Rheological measurements fitted to a modified Carreau–Yasuda model defining a melt yield stress were used to indicate changes in the particle dispersion with regard to TR. This analysis showed a monotonically increased dispersion of clay particles in the PP matrix with increasing extruder TR. The small‐strain tensile properties were tested at both ambient (20°C) and elevated (90°C) temperatures, and no significant changes were observed in the tensile strength or modulus as a function of TR. Instrumented Izod impact tests showed that the nanocomposite impact strength (σi) increased monotonically with increased TR by 70% from least dispersed to best dispersed, which was still 20% below the level for neat PP. Both the fracture initiation energy and propagation energy increased with TR, but the primary effect on σi came from the fracture propagation energy, which delivered 80% of the improvement. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Novel trifluoromethyl‐containing poly(amide–imide)s: Organosolubility, optical behavior, thermostability, and crystallinity
Authors: Behniafar Hossein , Sefid‐Girandehi Narges , Hosseinpour Mahdiyeh
Published: April 2012

A new dicarboxylic acid monomer, 2,6‐bis(1,3‐dioxo‐5‐carboxyisoindolin‐2‐yl)‐4,4′‐bis(trifluoromethyl)‐1,1′‐diphenyl ether (IFDPE), bearing two preformed imide rings was synthesized via a three‐step manner from 4‐(trifluoromethyl)phenol and 4‐chloro‐3,5‐dinitrobenzotrifluoride. The monomer IFDPE was then used to prepare a series of novel trifluoromethyl‐containing poly(amide–imide)s via a direct phosphorylation polycondensation with various aromatic diamines. The intrinsic viscosities of the polymers were found to be in the range 0.86–1.02 d/g. The weight‐ and number‐average molecular weights of the resulting polymers were determined with gel permeation chromatography. The polymeric samples were readily soluble in a variety of organic solvents and formed low‐color, flexible thin films via solution casting. The values of the absorption edge wavelength were determined by ultraviolet–visible spectroscopy, and all of the resulting poly (amide–imide)s films exhibited high optical transparency. The resulting polymers showed moderately high glass‐transition temperatures in the range 295–324°C and had 10% weight loss temperatures in excess of 524°C in nitrogen. The crystallinity extents were qualitatively investigated with wide‐angle X‐ray diffraction measurements. Scanning electron microscopy images revealed an agglomerated bulk with nonuniformity on the surface. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Piezoelectric polymeric bicomponent fibers produced by melt spinning
Authors: Lund Anja , Jonasson Christian , Johansson Christer , Haagensen Daniel , Hagström Bengt
Published: April 2012

Melt spinning of a novel piezoelectric bicomponent fiber, with poly(vinylidene fluoride) as the electroactive sheath component, has been demonstrated. An electrically conductive compound of carbon black (CB) and high density polyethylene was used as core material, working as an inner electrode. A force sensor consisting of a number of fibers embedded in a soft CB/polyolefin elastomer matrix was manufactured for characterization. The fibers showed a clear piezoelectric effect, with a voltage output (peak‐to‐peak) of up to 40 mV under lateral compression. This continuous all‐polymer piezoelectric fiber introduces new possibilities toward minimal single fiber sensors as well as large area sensors produced in standard industrial weaving machines. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Iminodiacetic acid‐containing polymer brushes grafted onto silica gel for preconcentration and determination of copper(II) in environmental samples
Authors: Panahi Homayon Ahmad , Mehmandost Nasrin , Moniri Elham , Galaev Igor Yu.
Published: April 2012

Silica gel has been modified by silylation with 3‐mercaptopropyltrimethoxysilane followed by graft polymerization of dimethylacrylamide and (N,N‐bis‐carboxymethyl)amino‐3‐allylglycerol‐co‐dimethylacrylamide, synthesized via the reaction of allyl glycidyl ether with iminodiacetic acid. The sorbent, poly(AGE/IDA‐co‐DMAA)‐grafted silica gel, has been characterized by FTIR, elemental analysis, thermogravimetric analysis (TGA), FT‐Raman, and scanning electron microscopy and studied for the preconcentration and determination of trace amounts of Cu(II) ion in environmental water samples. The optimum pH value for quantitative sorption of Cu(II) in batch mode was 5.5 and desorption was achieved, using 0.5 mol L−1 nitric acid. The sorption capacity of functionalized sorbent is 32.3 mg g−1. The chelating sorbent was reused for 15 sorption–desorption cycles without any significant change in sorption capacity. The profile of copper uptake by the sorbent reflected good accessibility of the chelating sites in the poly(AGE/IDA‐co‐DMAA)‐grafted silica gel. Scatchard analysis demonstrated homogeneous nature of binding sites. The equilibrium adsorption data of Cu(II) on modified sorbent were analyzed by Langmuir, Freundlich, Temkin, and Redlich–Peterson models. Based on equilibrium adsorption data, the Langmuir, Freundlich, and Temkin constants were determined as 0.0665, 4.26, and 8.34, respectively, at pH 5.5 and 20°C. Adsorption isotherms were analyzed at different temperatures to obtain free energy, enthalpy, and entropy of adsorption. The method was applied for Cu(II) determination in sea water samples. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and evaluation of a metal‐complexing imprinted polymer for Chinese herbs quercetin
Authors: Huangfu Fengyun , Wang Bing , Li Mingfang
Published: April 2012

In this study, a metal‐complexing imprinted polymer has been prepared using the complex of Quercetin and Co(II) (Qu‐Co(II)) as template (Quercetin is a kind of flavonoid, which is a class of important active ingredients of Chinese herbs.). The polymers were synthesized in the mixed solution of methanol and tetrahydrofuran by photo‐ and thermal‐initiated polymerization, respectively. The complex ratio between Qu and Co(II), as well as the ternary complexation of Qu, Co(II), and acrylamide, was assessed in differential UV absorption spectrometry. Fourier transform infrared spectra (FTIR) were useful to verify whether the polymers prepared in two ways had the same molecular structure. The effect of initiation mode was studied by the transmission electron microscopy (TEM) and equilibrium binding experiments. Isothermal adsorption and selectivity experiments showed that molecularly imprinted polymers exhibited high affinity and specific recognition for Qu by introducing cobalt ion. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Reversible immobilization of glycoamylase by a variety of Cu2+‐chelated membranes
Authors: Baydemir Gözde , Derazshamshir Ali , Andaç Müge , Andaç Cenk , Denizli Adil
Published: April 2012

Glycoamylase (AMG) is an γ‐amylase enzyme which catalyzes the breakdown of large α(1,4)‐linked malto‐oligosaccharides to glucose. It is an extracellular enzyme and is excreted to the culture medium. In this study, AMG was immobilized on a variety of metal affinity membranes, which were prepared by chelating Cu2+ ions onto poly(hydroxyethyl methacrylate) (PHEMA) using N‐methacryloyl‐(L)‐histidine methyl ester (MAH), N‐methacryloyl‐(L)‐cysteine methyl ester (MAC), and N‐methacryloyl‐(L)‐phenylalanine methyl ester (MAPA) as metal‐chelating comonomers for reversible immobilization of AMG. The PHEMAH, PHEMAC, PHEMAPA membranes were synthesized by UV‐initiated photo‐polymerization and Cu2+ ions were chelated on the membrane surfaces. Cu2+‐chelated membranes were characterized by swelling tests, SEM, contact angle measurements, elemental analysis, and FTIR. AMG immobilization on the Cu2+‐chelated membranes was performed by using aqueous solutions of different amounts of AMG at different pH values and Cu2+ loadings. Durability tests concerning desorption of AMG and reusability of the Cu2+‐chelated membranes yielded acceptable results. It was computationally determined that AMG possesses four likely Cu2+/Zn2+ binding sites, away from the catalytic site, to which the metal‐chelated membranes can be efficiently used. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
The order addition effect of carbon black/graphite on the electrical properties of rubber composites
Authors: Mansour S. A. , El‐Salam M. A. , Moharram A. H. , Hussein M. , Al‐Agel Faisal A. M.
Published: April 2012

Acrylonitrile‐butadiene rubber (NBR) filled with two types of fillers [high abrasion furnace carbon black (C), and graphite (G)] is made to find out the effect of order addition of C and G on the electrical conductivity of the composites. The temperature and frequency dependence of the (dc and ac) conductivity and dielectric constants have been measured. The values of the thermal expansion and thermal conduction coefficient of NBR rubber lead to the difference in I–V characteristics between CB‐ and G‐NBR rubber composites during the measurement. When graphite is first added to NBR, the electrical conductivity of (GC20‐20) matrix is larger than that of the (CG20‐20) matrix, whereas the carbon black is added first. At low temperature (T < 90°C), the higher values of the dielectric constant (ε′) for the sample GC20‐20 compared with that of the CG20‐20 sample is due to the conducting nature and structure of graphite, whereas the carbon shows less crystallinity and conductivity than graphite. Opposite behavior is noticed at temperature higher than 90°C. The dc conductivity of all composites increases with increasing temperature exhibiting a positive temperature coefficient of conductivity (PTCσ). The conductivity at high temperatures region is controlled by the thermal excitation transport mechanism, whereas at low temperatures region is dominated by tunneling process. The increase in the value of dielectric constant (ε′) with temperatures for the sample GC20‐20 compared with the sample CG20‐20 is due to the conducting nature and structure of graphite, and the carbon less crystalline than the graphite. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Production and characterization of polycaprolactone nanofibers via forcespinning™ technology
Authors: McEachin Zachary , Lozano Karen
Published: April 2012

Among the myriad of methods for polymer nanofiber production, there are only a few methods that can produce submicron range fibers in bulk from melt or solution samples. The Forcespinning™ method allows a substantial increase in sample yield while simultaneously maintaining the integrity of uniform fibers in the nanometer range. The high production yield of such a method greatly reduces the time needed to produce bulk quantities of fibers which may be critical in many fields of research and industry, in particularly in fields relating to biopolymers. The aim of this study was to use this method to form nonwoven mats of polycaprolactone (PCL) nanofibers and to quantitatively analyze the production and characterization of the produced fibers. The bulk PCL was dissolved in dichloromethane and the solutions were forcespun at varying speeds ranging from 3000 to 9000 rpm. It was observed that fiber diameter decreased with increasing rotational speed. The average fiber diameter at 9000 rpm was 220 nm with a standard deviation of ±98 nm. The morphology and degree of crystallinity were characterized by scanning electron microscopy, differential scanning calorimetry, and X‐ray diffraction. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Polyelectrolyte complex nanoparticles for protection and delayed release of enzymes in alkaline pH and at elevated temperature during hydraulic fracturing of oil wells
Authors: Barati Reza , Johnson Stephen J. , McCool Stan , Green Don W. , Willhite G. Paul , Liang Jenn‐Tai
Published: April 2012

Polyethylenimine‐dextran sulfate polyelectrolyte complexes (PECs) were used to entrap two enzymes used to degrade polymer gels following hydraulic fracturing of oil wells to obtain delayed release and to protect the enzyme from harsh conditions. Degradation, as revealed by reduction in viscoelastic moduli, of borate‐crosslinked hydroxypropyl guar gel by commercial enzyme loaded in polyelectrolyte nanoparticles was delayed up to 11 h, compared with about 3 h for equivalent systems where the enzyme mixture was not entrapped. PEC nanoparticles also protected both enzymes from denaturation at elevated temperature and pH. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Solid‐state synthesis and characterization of polyaniline/nano‐TiO2composite
Authors: Abdiryim Tursun , Ubul Aminam , Jamal Ruxangul , Tian Yuchuan , Awut Tunsagul , Nurulla Ismayil
Published: April 2012

Polyaniline/nano‐TiO2composites with the content of nano‐TiO2varying from 6.2 wt % to 24.1 wt % were prepared by using solid‐state synthesis method at room temperature. The structure and morphology of the composites were characterized by the Fourier transform infrared (FTIR) spectra, ultraviolet‐visible (UV–vis) absorption spectra, X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The electrochemical performances of the composites were investigated by galvanostatic charge–discharge measurement, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The results from FTIR and UV–vis spectra showed that the composites displayed higher oxidation and doping degree than pure PANI. The XRD and morphological studies revealed that the inclusion of nano‐TiO2particles hampered the crystallization of PANI chains in composites, and the composites exhibited mixed particles from free PANI particles and the nano‐TiO2entrapped PANI particles. The galvanostatic charge–discharge measurements indicated that the PANI/nano‐TiO2composites had higher specific capacitances than PANI. The composite with 6.2 wt % TiO2had the highest specific capacitance among the composites. The further electrochemical tests on the composite electrode with 6.2 wt % TiO2showed that the composite displayed an ideal capacitive behavior and good rate ability. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Structural changes as a result of processing in thermoplastic bloodmeal
Authors: Verbeek Casparus J. R. , van den Berg Lisa E.
Published: April 2012

Bloodmeal (BM) can be thermoplastically processed resulting in a material with good mechanical properties by using a correct combination of additives. In this article, combinations of water, sodium sulfite (SS), sodium dodecyl sulfate (SDS), and urea were compounded with BM, and water absorption, solubility, thermal stability, and protein secondary structure were assessed. Thermal stability of processed plastics was reduced when using 2 or 3 pphbm (parts per hundred parts BM) SS and 20 pphbm urea, mostly indicative of a reduction in covalent crosslinking. SS was required for chain mobility during processing, however, without sufficient plasticization degradation will occur instead of melt formation. SDS further improved processability and consolidation leading to increased water absorption and solubility, indicative of a reduction in chain interactions. It was found that BM proteins are highly denatured and thermoplastic processing reduced ordered structures further. Additional minor structural changes occurred as a result of reduced covalent and noncovalent interactions after processing. It was concluded that the increase in water absorption and solubility was due to changes in intermolecular and intramolecular interactions, rather than substantial structural changes. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis of poly(lactic acid‐co‐menthol) via direct melt polycondensation and its characterization
Authors: Mao Chao‐Xu , Luo Shi‐He , Wang Qun‐Fang , Xiong Jin‐Feng , Wang Zhao‐Yang
Published: April 2012

Directly starting from D,L‐lactic acid (LA) and L‐menthol, poly(lactic acid‐co‐menthol) (PLAM) as potential solid mint flavor was synthesized via melt polycondensation. The synthetic conditions, including type and dosage of catalyst, temperature and time of copolymerization, were discussed. The structure and properties of the copolymer were systematically characterized with FTIR, 1H‐NMR, GPC, DSC, TG, and XRD. The influences of molar feed ratios on the properties of PLAM were also discussed. The copolymer PLAM with the biggest Mw of 11,600 Da was obtained. The Tg of PLAM is lower than the Tg of homopolymer poly(D,L‐lactic acid) (PDLLA), and all copolymers have higher thermal decomposition temperature. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
The effects of long‐term exposure to extremely low‐frequency magnetic fields on bone formation in ovariectomized rats
Authors: Celik Mustafa S. , Gur Ali , Akdağ Zulkuf , Akpolat Veysi , Guven Kemal , Celik Yusuf , Sarac Aysegul J. , Otçu Selcuk
Published: April 2012

The effects of long‐term extremely low‐frequency magnetic field (ELF‐MF) exposure on bone formation and biochemical markers were investigated in ovariectomized rats. Sixty mature female Sprague–Dawley rats were randomly divided into four different groups (n = 15): (i) unexposed control (CTL); (ii) ovariectomized only (OVX); (iii) non‐ovariectomized, exposed (SHAM + ELF‐MF); and (iv) ovariectomized, exposed (OVX + ELF‐MF). The third and fourth groups were exposed to 1.5 mT ELF‐MF for 4 h a day for 6 months. Bone mineral density (BMD) was determined using dual energy X‐ray absorption (DEXA) measurements. The formation and resorption of bone were evaluated using bone‐specific alkaline phosphatase (BAP), osteocalcin, osteoprotogerin, and N‐telopeptide. After 6 months of ELF‐MF therapy, BMD values were significantly lower in the OVX group and higher in the OVX + ELF‐MF and SHAM + ELF‐MF groups than they were before therapy (P < 0.001). Although there was no significant difference in BMD values among the groups before therapy, the BMD values increased significantly after 6 months in the OVX + ELF‐MF and SHAM + ELF‐MF groups and were reduced in the OVX group compared to the CTL group (P < 0.001). The concentrations of BAP, osteocalcin, osteoprotogerin, and N‐telopeptide in the three experimental groups also changed in a significant way compared to the CTL group. The results of the present study suggest that osteoporosis can be inhibited by ELF‐MF stimulation treatments. It was also concluded that ELF‐MF may be useful in the prevention of osteoporosis in ovariectomized rats. Bioelectromagnetics 33:543–549, 2012. © 2012 Wiley Periodicals, Inc.
Calcium efflux of plasma membrane vesicles exposed to ELF magnetic fields—test of a nuclear magnetic resonance interaction model
Authors: Sun Wenjun J. , Mogadam Mehri Kaviani , Sommarin Marianne , Nittby Henrietta , Salford Leif G. , Persson Bertil R.R. , Eberhardt Jacob L.
Published: April 2012

The question whether very weak, low frequency magnetic fields can affect biological matter is still under debate. The theoretical possibility of such an interaction is often questioned and the site of interaction in the cell is unknown. In the present study, the influence of extremely weak 60 Hz magnetic fields on the transport of Ca2+ was studied in a biological system consisting of highly purified plasma membrane vesicles. We tested a newly proposed quantum mechanical model postulates that polarization of hydrogen nuclei can elicit a biological effect. Vesicles were exposed for half an hour at 32 °C and the calcium efflux was studied using radioactive 45Ca2+ as a tracer. A static magnetic field of 26 µT and time‐varying magnetic fields with a frequency of 60 Hz and amplitudes between 0.6 and 6.3 µT were used. The predictions of the model, proposed by Lednev, that at a frequency of 60 Hz the biological effect under investigation would significantly be altered at the amplitudes of 1.3 and 3.9 µT could not be confirmed. Bioelectromagnetics 33:535–542, 2012. © 2012 Wiley Periodicals, Inc.