bluuebunny/crossref_metadata_2025 huggingface dataset:
Capacity building in environmental and occupational health in Sri Lanka
Authors: Wickremasinghe Ananda R. , Peiris‐John Roshini , Nandasena Sumal , Delzell Elizabeth , Tipre Meghan , Sathiakumar Nalini
Published: December 2011

Background

Although environmental and occupational health (EOH) research and services in Sri Lanka have a long history, policies related to EOH are outdated.

Methods

We review the International Training and Research in Environmental and Occupational Health (ITREOH) program in Sri Lanka that commenced in 2006 as a collaboration between the University of Alabama at Birmingham and the Faculty of Medicine of the University of Kelaniya, Sri Lanka.

Results

The program has trained over 20 scientists in conducting EOH research. New pioneering research in EOH was initiated. The program was instrumental in furthering the training and research in EOH by initiating a MPH degree program, the first in the country.

Conclusions

The program has established North–South, South–South and in‐country collaborations between institutions and scientists, increasing the visibility of EOH in the future. Am. J. Ind. Med. 56:1–10, 2013. © 2011 Wiley Periodicals, Inc.
Longitudinal mental health impact among police responders to the 9/11 terrorist attack
Authors: Bowler Rosemarie M. , Harris Matthew , Li Jiehui , Gocheva Vihra , Stellman Steven D. , Wilson Katherine , Alper Howard , Schwarzer Ralf , Cone James E.
Published: December 2011

Background

Among police responders enrolled in the World Trade Center Health Registry (WTCHR), Post‐traumatic Stress Disorder (PTSD) was almost twice as prevalent among women as men 2–3 years after the 9/11 attacks.

Methods

Police participants in the WTCHR Wave 1 survey 2–3 years after 9/11/01, were reassessed for probable PTSD at Wave 2, 5–6 years after 9/11/01, using PCL DSM‐IV criteria.

Results

Police participants in the Wave 2 survey included 2,527 men, 413 women. The prevalence of “Probable PTSD” was 7.8% at Wave 1 and 16.5% at Wave 2. Mean PCL scores increased from 25.1 to 29.9 for men and 28.6 to 32.2 for women. Prevalence of PTSD was higher for women than for men at Wave 1 (χ2 = 10.882, P = 0.002), but not Wave 2 (χ2 = 2.416, P = 0.133). Other risk factors included losing one's job after 9/11 and being disabled.

Conclusions

Prevalence of probable PTSD among police doubled between 2003–2004 and 2006–2007. After the 2‐year time span, the gender difference was no longer significant; prevalence of PTSD symptoms increased and there was a substantial amount of co‐morbidity with other mental health problems. Further development of prevention and intervention strategies for police responders with symptoms of PTSD is needed. The observed upward trend in PCL scores over time in police officers with PCL scores less than 44, suggests that PTSD prevention and intervention strategies should be applied to all police affected by the 9/11 attacks, not limited just to those with PTSD symptoms. Am. J. Ind. Med. 55:297–312, 2012. © 2011 Wiley Periodicals, Inc.
Comparison of risk factors for shoulder pain and rotator cuff syndrome in the working population
Authors: Bodin Julie , Ha Catherine , Chastang Jean‐François , Descatha Alexis , Leclerc Annette , Goldberg Marcel , Imbernon Ellen , Roquelaure Yves
Published: December 2011

Background

To compare risk factors for shoulder pain without and with rotator cuff syndrome (RCS).

Methods

A total of 3,710 workers of a French region were randomly included in the cross‐sectional study between 2002 and 2005. Personal and occupational risk factors were assessed during a physical examination and by a self‐administered questionnaire. Multinomial logistic modeling was used for the following outcomes: no shoulder pain and no RCS (reference), shoulder pain without RCS (called “shoulder pain”) and RCS, separately for men and women.

Results

The prevalence rates of “shoulder pain” for men and women were 28.0% and 31.1%, respectively, and the prevalence rates of RCS were 6.6% and 8.5%, respectively. In men, “shoulder pain” and RCS were associated with age, high‐perceived physical exertion, and arm abduction. Automatic work pace and low supervisor support were associated with “shoulder pain,” and high psychological demand and low skill discretion with RCS. In women, “shoulder pain” and RCS were associated with age, repetitiveness of tasks, and low supervisor support. High perceived physical exertion and exposure to cold temperatures were associated with “shoulder pain.”

Conclusions

Age was more strongly associated with RCS than with shoulder pain without RCS for both genders. Biomechanical and psychosocial factors were associated with “shoulder pain” and RCS and differed between genders. Am. J. Ind. Med. 55:605–615, 2012. © 2011 Wiley Periodicals, Inc.
The relationship between fatigue‐related factors and work‐related injuries in the saskatchewan farm injury Cohort Study
Authors: Lilley Rebbecca , Day Lesley , Koehncke Niels , Dosman James , Hagel Louise , William Pickett ,   for the Saskatchewan Farm Injury Cohort Study
Published: December 2011

Background

The objective was to examine the relationship between seasonal variations in sleep quantity and work‐related injuries on Saskatchewan farms.

Methods

A cross‐sectional analysis of data from the Saskatchewan Farm Injury Cohort Study was conducted. Analyses were restricted to workers, aged ≥16 years. The primary outcome was work‐related injury in the last year. Logistic regression models were used to identify associations between sleep quantity and farm injury.

Results

After controlling for confounding variables peak production season sleep was not associated with increased odds of injury. However, those obtaining ≤5 hr sleep per night during non‐peak production seasons had increased odds of injury (OR 2.42, 95% CI 1.04–5.59) compared with those sleeping ≥7 hr per night.

Conclusions

We identified that restricted sleep durations, in certain seasons, placed farmers, and farm workers at risk of injury. Agricultural injury intervention programs need to consider the role of seasonal‐related variations in sleep on farm injury. Am. J. Ind. Med. 55:367–375, 2012. © 2011 Wiley Periodicals, Inc.
Longevity candidate genes and their association with personality traits in the elderly
Authors: Luciano Michelle , Lopez Lorna M. , de Moor Marleen H.M. , Harris Sarah E. , Davies Gail , Nutile Teresa , Krueger Robert F. , Esko Tõnu , Schlessinger David , Toshiko Tanaka , Derringer Jaime L. , Realo Anu , Hansell Narelle K. , Pergadia Michele L. , Pesonen Anu‐Katriina , Sanna Serena , Terracciano Antonio , Madden Pamela A.F. , Penninx Brenda , Spinhoven Philip , Hartman Catherina A. , Oostra Ben A. , Janssens A. Cecile J.W. , Eriksson Johan G. , Starr John M. , Cannas Alessandra , Ferrucci Luigi , Metspalu Andres , Wright Margeret J. , Heath Andrew C. , van Duijn Cornelia M. , Bierut Laura J. , Raikkonen Katri , Martin Nicholas G. , Ciullo Marina , Rujescu Dan , Boomsma Dorret I. , Deary Ian J.
Published: December 2011

Human longevity and personality traits are both heritable and are consistently linked at the phenotypic level. We test the hypothesis that candidate genes influencing longevity in lower organisms are associated with variance in the five major dimensions of human personality (measured by the NEO‐FFI and IPIP inventories) plus related mood states of anxiety and depression. Seventy single nucleotide polymorphisms (SNPs) in six brain expressed, longevity candidate genes (AFG3L2, FRAP1, MAT1A, MAT2A, SYNJ1, and SYNJ2) were typed in over 1,000 70‐year old participants from the Lothian Birth Cohort of 1936 (LBC1936). No SNPs were associated with the personality and psychological distress traits at a Bonferroni corrected level of significance (P < 0.0002), but there was an over‐representation of nominally significant (P < 0.05) SNPs in the synaptojanin‐2 (SYNJ2) gene associated with agreeableness and symptoms of depression. Eight SNPs which showed nominally significant association across personality measurement instruments were tested in an extremely large replication sample of 17,106 participants. SNP rs350292, in SYNJ2, was significant: the minor allele was associated with an average decrease in NEO agreeableness scale scores of 0.25 points, and 0.67 points in the restricted analysis of elderly cohorts (most aged >60 years). Because we selected a specific set of longevity genes based on functional genomics findings, further research on other longevity gene candidates is warranted to discover whether they are relevant candidates for personality and psychological distress traits. © 2011 Wiley Periodicals, Inc.
Sound insulation in polymer/inorganic particle composites. I. Theoretical model
Authors: Liang Ji‐Zhao , Jiang Xing‐Hua
Published: December 2011

The sound insulation behavior of inorganic particulate‐filled polymer composites was analyzed by means of acoustics theory in this article to reveal the mechanisms of sound insulation. On the basis of it, a physical model of the sound wave transfer in the composite system was established, and a relevant transmission loss equation was derived. The transmission loss of the glass bead‐filled polyethylene composites was estimated by using this equation. The results showed that the calculated transmission loss of the composites increased linearly with an increase of the glass bead volume fraction, and it increased nonlinearly with increasing sound frequency. The sensitivity of the transmission loss to the sound frequency was significant at low sound frequency. The transmission loss decreased nonlinearly with the size of added glass bead when the volume fraction was constant. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Preparation and characterization of novel transparent Eu(AA)3‐polyurethane acrylate copolymeric materials
Authors: Zhou Li‐Ming , Gao Li‐Jun , Fang Shao‐Ming , Sun Guang‐Hui , Hu Min , Guo Liang‐Qi , Han Cheng , Zhang Liu‐Cheng
Published: December 2011

The rare earth (RE) salts Eu(AA)3 (AA: acrylic acid group) and the macromonomers of polyurethane acrylate (MPUA) containing vinyl groups at the end of the chain are prepared for achieving a novel transparent Eu(AA)3‐polyurethane acrylate (Eu‐PUA) materials by copolymerization. The structure and properties of the Eu(AA)3 and the Eu‐PUA have been systematically characterized by infrared spectroscopy (FTIR), proton and carbon nuclear magnetic resonance (1H‐NMR, 13C‐NMR), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), and fluorescence spectrophotometer. It is proved that the Eu(AA)3 have been successfully bonded onto the molecular chains of the polyurethane acrylate and the glass transition temperature (Tg) of the polyurethane acrylate increases at the presence of Eu(AA)3. In addition, the Eu‐PUA materials show favorable thermal stability and transparence. Typically, the fluorescence spectra show that the strongest fluorescence emission peak of the Eu‐PUA material appears at 614 nm at the excitation wavelength of 395 nm. This demonstrates that such material can be applied to functional optical materials in the future. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Studies on the properties of poly(vinyl alcohol) film plasticized by urea/ethanolamine mixture
Authors: Jiang Xiancai , Tan Bowen , Zhang Xiaofei , Ye Dezhan , Dai Hua , Zhang Xi
Published: December 2011

This study investigated the effects of urea/ethanolamine mixture (UE) on the crystallinity, thermal, and mechanical properties of poly(vinyl alcohol) (PVA) films. PVA films were prepared from solutions containing PVA, urea, ethanolamine, and water by casting and evaporating at 50°C for 12 h. The plasticization efficiency of UE was compared with that of glycerol (GL), the conventional plasticizer for PVA. The properties of PVA films plasticized by UE and GL, abbreviated to UE‐plasticized PVA film and GL‐plasticized PVA film, respectively, were investigated by Fourier‐transform infrared spectroscopy, X‐ray diffraction, differential scanning calorimetry, thermogravimetric analysis, and mechanical testing. It was proved that UE could form more stable hydrogen bonding with the hydroxyl group of PVA molecule and was more effective in breaking the hydrogen bonds between the hydroxyl groups. Thus, the crystallinity of UE‐plasticized PVA films was lower than that of GL‐plasticized PVA films. The melting temperatures of UE‐plasticized PVA films were lower than those of GL‐plasticized PVA films. It was found that UE‐plasticized PVA film showed a higher degradation temperature compared with GL‐plasticized PVA film. The degree of swelling of UE‐plasticized PVA film was higher than that of GL‐plasticized PVA film but solubility (S) of UE‐plasticized PVA film was lower in aqueous solution. Furthermore, UE‐plasticized PVA films show lower tensile strength and higher elongation at break (E) than those of GL‐plasticized PVA films. The tensile strength, E, and Young's modulus of PVA film containing 30% UE mixture reached 50.78 MPa, 591.19% and 76.9 MPa, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Investigation of Pb(II) adsorption onto natural and synthetic polymers
Authors: Ahmetli G. , Yel E. , Deveci H. , Bravo Y. , Bravo Z.
Published: December 2011

Adsorption of toxic metal ion Pb(II) onto two different insoluble humic acids (IHAs) obtained from Beysehir (BIHA) and Ermenek (EIHA) low grade lignites and two synthesized terpolymers: styrene‐divinylbenzene‐methacrylic acid (SDBM) and styrene‐divinylbenzene allylmethacrylate (SDBAM) were investigated and compared with commercial activated carbon (AC). The synthesized polymers were characterized by FTIR. Effects of pH (in neutral and acidic range), time, and initial metal concentration on the effectiveness of IHAs and terpolymers were determined. All synthesized adsorbents could adsorb Pb(II) with much higher capacity at half of the retention of AC in acidic medium. The adsorption capacities varied in the range of 51–76 mg g−1. The affinity order of polymers in acidic medium for Pb(II) ions was observed as: SDBAM>SDBM>BIHA≈EIHA>AC. IHAs fit Freundlich model while SDB polymers were fitting Langmuir isotherm. The maximum adsorption capacities in neutral medium were 48 mg g−1 for SDBM and 15 mg g−1 for BIHA. Desorption studies for the polymer of highest performance indicated that about 90% desorption was achieved at 5 h by using EDTA regenerant solution. The polymer can be used repeatedly in Pb(II) adsorption with close capacities to initial use. The higher selectivity of SDBAM to Pb(II) ions in multimetal solution was also indicated in the study. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effects of plasticization conditions on the structures and properties of cellulose packaging films from ionic liquid [BMIM]Cl
Authors: Jin Zhengwei , Wang Shuo , Wang Jianqing , Zhao MingXu
Published: December 2011

By using natural softwood pulp with higher degree of polymerization (DP = 1460) as cellulose source, 1‐butyl‐3‐methylimidazolium chloride ([BMIM]Cl) ionic liquid as solvent and glycerol as plasticizer, a novel cellulose packaging film was prepared. The effects of plasticization conditions on the structures, mechanical properties, permeability for oxygen and water vapor were measured by Wide‐angle X‐ray scattering, thermogravimetric analysis, scanning electron microscopy (SEM), and other techniques. The investigations suggested that the glycerol concentration and plasticizing time had great effect on the properties of the regenerated cellulose films. The crystal transformation of cellulose I to cellulose II occurred during the dissolution and regeneration process, combining with the decrease of thermal stability. The tensile strength decreased rapidly with the addition of glycerol and prolongation of plasticizing time. However, elongation at break of the regenerated cellulose films increased at first and then decreased with increasing of glycerol concentration and plasticizing time. The morphologies for the fracture surface obtained from SEM images showed transformation of typical brittle fracture to plastic deformation with increasing of glycerol concentrations. It was also found that both water vapor permeability and oxygen permeability of the regenerated cellulose films decreased slowly with increasing of glycerol concentrations and plasticizing time, but water vapor permeability and oxygen permeability presented an almost opposite trend. The films prepared by using ionic liquid technology would be used in food packaging or other fields as a kind of green packaging material. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Correlation between spinning temperature, membrane morphology, and performance of Psf/PVP/NMP/Water hollow fiber membrane forming system
Authors: Dahe Ganpat J. , Teotia Rohit S. , Bellare Jayesh R.
Published: December 2011

Asymmetric polysulfone (Psf)/polyvinylpyrrolidone (PVP) hollow fiber membranes were fabricated via dry‐wet spinning process in a custom made apparatus with controlled spinneret and spinning lines temperature. This study investigated the effect of isothermal spinning temperatures on morphology, performance, and their relationship. The hollow fibers prepared at isothermal conditions provide greater control over morphology and performance. Thickness of skin at inner side varied with spinning temperature, while morphology at outer cross‐section and surface remained same. Three different layers of skin were observed by high‐resolution SEM and nodular skin topography by AFM. The viscosity of dope solution was tremendously varied with temperature, which in turn dictates the precipitation rate. Precipitation rate was found to be the controlling parameter for skin thickness. Skin thickness varied from 7.04 to 2.44 μm, as temperature of spinning was changed from 15 to 40°C. The membrane performance was studied by pure water permeability and solute rejection by gel permeation chromatography. Pure water flux increased from 17 to 30 mL/(m2 h mmHg) and NMWCO from 13,000 Da to 25,000 Da, with increase in spinning temperature, thereby demonstrating the control of spinning temperature on morphology and membrane performance. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Natural rubber nanocomposites with functionalized carbon nanotubes: Mechanical, dynamic mechanical, and morphology studies
Authors: Abdullateef Adedigba A. , Thomas Selvin P. , Al‐Harthi Mamdouh A. , De S. K. , Bandyopadhyay Sri , Basfar A.A. , Atieh Muataz A.
Published: December 2011

Recent attempts toward improving the properties of natural rubber (NR) by using carbon nanotubes (CNT) as filler were not successful due to low dispersion of CNT in NR. This article reports the results of studies on improvement of dispersion of CNT in NR by acid modification of CNT surface. Fourier transform infrared spectra confirmed the presence of COOH groups on the CNT surface. On the basis of results of studies on using differential scanning calorimetry, universal testing machine, dynamic mechanical tester, thermogravimetric analysis, electrical properties, and transmission electron microscopy, it is concluded that acid modification of CNT leads to improvement in thermal stability, stress–strain, and dynamic mechanical properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
A novel type nanocomposite coating based on alkyd‐melamine formaldehyde resin containing modified silica: Preparation and film properties
Authors: Bal Ayça , Acar Işıl , Güçlü Gamze
Published: December 2011

In this study, the surface of the silica particles was modified with glycidoxypropyl trimethoxysilane and then silica nanoparticle modified alkyd‐melamine resins were synthesized by two methods, namely in situ (IS) polymerization and blending (BL) methods. After alkyd resins containing 40% oil were prepared; these resins were blended with 30% of a commercial melamine‐formaldehyde. The films of the alkyd‐melamine formaldehyde resins were prepared from 60% solid content in xylene solutions. These films were cured at 170°C and properties of the films were determined. The effect of modified silica on the film properties and thermal behaviors of the resins was investigated. The scanning electron micrographs of the nanocomposite resin showed that modified silica particles have been dispersed into polymer resins substantially for IS polymerization. According to results of surface coating tests, we can say that, film properties of the resins prepared by IS method were better than that of prepared by BL method. In addition, using modified silica did not have a negative effect on the thermal behaviors of the resins with respect to thermogravimetric analysis. Furthermore, adding the modified silica in the resin structure caused increasing the thermal stability especially for resins prepared by IS method. As a result, alkyd‐melamine resins containing modified silica nanoparticle are suitable for manufacturing of industrial baking enamels. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Preparation and characterization of magnetic polyimide hybrid thin films
Authors: Sun Jiuli , Zhang Qiuyu , Guo Feige , Gu Junwei , Zhang Junping
Published: December 2011

Magnetic polyimide hybrid thin films were synthesized from pyromellitic dianhydride (PMDA), 4,4′‐oxydianiline (ODA), and Fe3O4 magnetic nanoparticles via thermal imidiazation in nitrogen environments. The magnetic polyimide hybrid thin films were analyzed and characterized by Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), and scanning electron microscopy (SEM). The magnetic properties of magnetic nanoparticles and polymer hybrid thin films were assessed using a vibrating sample magnetometer (VSM), and the physical properties of hybrid thin films were tested. Results revealed that the magnetic polyimide hybrid thin films had superparamagnetic behavior and excellent mechanical properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Chitosan/carbon nanotube composite beads: Preparation, characterization, and cost evaluation for mercury removal from wastewater of some industrial cities in Egypt
Authors: Shawky Hosam A. , El‐Aassar Abdel Hameed M. , Abo‐Zeid Dalia E.
Published: December 2011

Composite beads composed of chitosan (CS) with different carbon nanotubes (CNTs) were prepared by the incorporation of single‐walled carbon nanotubes (SWCNTs), multiwalled carbon nanotubes (MWCNTs), and carboxylic multiwalled carbon nanotubes (MWCNT‐COOHs). A protected crosslinking method was used for the preparation of the CS/CNTs beads by the reaction of the beads with Hg(II) as the protector. Scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis were used to characterize the prepared beads. The adsorption performance of the prepared beads was investigated for the removal of Hg(II). The results show that beads prepared by the protected crosslinking technique removed 2.5 times more Hg(II) from solution than beads prepared by normal crosslinking. The maximum Hg(II) removal values were 148.7, 183.2, 167.5, and 172.7 mg/g by CS, MWCNT‐COOH‐impregnated CS beads, MWCNT‐impregnated CS beads, and SWCNT‐impregnated CS composite beads, respectively. The optimum removal conditions were pH = 4, contact time = 40 min, and temperature = 70°C. The equilibrium adsorption isotherm data of the beads exhibited a better fit to the Langmuir isotherm model. The reusability of Hg(II) sorption by the prepared beads was investigated to evaluate their repeated availability performance in water treatment. Quantitative removal of mercury from industrial wastes was demonstrated. A statistical analysis of the replacement cost of these sorbents revealed that SWCNTs, MWCNTs, and MWCNT‐COOH could possibly be cost‐effective sorbents in water treatment, regardless of their high unit cost at this time. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and characterization of polyphenols derived from 4‐fluorobenzaldeyde: The effect of electron‐donating group on some physical properties
Authors: Kaya İsmet , Kamacı Musa , Arıcan Fatih
Published: December 2011

In this study, we proposed to investigate how the effect of electron‐donating methyl (CH3) group at p‐position of amin (NH2) group in aminophenol (AP) compound affected thermal stability, optical, electrochemical properties, and conductivity measurement. For this reason, we choice 2‐AP and 2‐amino‐4‐methylphenol compounds and synthesized phenolic monomers by condensation reactions 4‐fluorobenzaldehyde with aromatic amino phenols. Then, these monomers were converted to their polyphenol derivatives by oxidative polycondensation reactions in an aqueous alkaline medium. Structural characterizations were carried out by FTIR, NMR, and size exclusion chromatography. Cyclic voltammetry was used to determine the electrochemical oxidation‐reduction characteristics. Optical properties were investigated by UV–vis and fluorescence analyses. Solid state electrical conductivities were measured on polymer films by four‐point probe technique using an electrometer. Thermal data of monomer/polymer and polymers were obtained by TG‐DTA and DSC techniques, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Photo, thermal, and ultrasonic degradation of EGDMA‐crosslinked poly(acrylic acid‐co‐sodium acrylate‐co‐acrylamide) superabsorbents
Authors: Shukla Neelesh Bharti , Madras Giridhar
Published: December 2011

Superabsorbent polymers (SAPs) based on acrylic acid (AA), sodium acrylate (SA), and acrylamide (AM) were synthesized by inverse suspension polymerization using ethylene glycol dimethacrylate as the crosslinking agent. The equilibrium swelling capacities and the rates of swelling of SAPs varied with the AM content and followed first‐order kinetics. The photodegradation of SAPs in their equilibrium swollen state was carried out by monitoring their swelling capacity and the residual weight fraction. The SAPs degraded in two stages, wherein the swelling capacity increased to a maximum and then subsequently decreased. Thermogravimetric analysis of the SAPs indicated that the copolymeric superabsorbents had intermediate thermal stability between the homopolymeric superabsorbents. The activation energies of SAPs with 0, 20, and 100 mol % AM content were determined by Kissinger method and were found to be 299, 248, and 147 kJ mol−1, respectively. The ultrasonic degradation of the superabsorbents was carried out in their equilibrium swollen state, and the change in the viscosity with ultrasonication time was used to quantify the degradation. The ultrasonic degradation of AA/SA superabsorbent was also investigated at various ultrasound intensities. The degradation rate coefficients were found to increase with the intensity of ultrasound. The ultrasonic degradation of AA/SA/AM (20% AM) was also carried out, and degradation rate was found to be more than that of the AA/SA superabsorbent. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Achieving shape memory: Reversible behaviors of cellulose–PU blends in wet–dry cycles
Authors: Luo Hongsheng , Hu Jinlian , Zhu Yong , Zhang Sheng , Fan Ying , Ye Guangdou
Published: December 2011

Shape memory effect (SME) was achieved for cellulose–polyurethane (PU) blends of different compositions in wet–dry cycles, featuring that the amorphous cellulose and the PU content served as the fixing phase and the recovery phase, respectively. The dependence on the compositions of the fixity ratio and the recovery ratio was quantitatively measured by tensile tests. The morphological and thermal properties of the blends were further investigated by scanning electron microscopy and thermogravimetric analysis. The storage modulus of the blends varied reversibly in the wet–dry cycles, as determined by dynamic mechanical analysis. Furthermore, the microstructure of the blends reversibly changed correspondingly, as determined by wide‐angle X‐ray scattering diffraction and Fourier transform infrared. It was predicted that the reversible transition in different amorphous cellulose structures triggered by water led to the reversible variation in modulus as well as the wet–dry SME of the blends. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Biological evaluation of a new organically modified ceramic‐based dental restorative resin
Authors: Lizymol P. P. , Mohanan P. V. , Sabareeswaran A. , Krishnan V. Kalliyana
Published: December 2011

Material tissue interactions of a newly developed organically modified ceramic (ormocer)‐based dental restorative composite based on a resin containing mixture of alkoxides of silicone and calcium with polymerizable methacrylate end groups are discussed in this study. Admira, a commercially available ormocer was used as control. A sol–gel process has been used to synthesize organically modified ceramic resins from liquid precursors, which allow one to produce inorganic–organic hybrid polymer materials, which can be functionalized to optimize their physical and chemical properties. Besides, the resulting material properties have been significantly modified by further technological processing such as photochemical curing of the materials by incorporating dimethacrylate groups as organically polymerizable units. Intracutaneous (intradermal) irritation test is found not to elicit any gross signs of tissue reaction. The results of maximization test for delayed hypersensitivity also did not show any adverse skin reaction during the induction or challenge period. Histological analysis after 1, 4, and 12 weeks of subcutaneous implantation of restorative composite resin on the dorsal surface on one side of the spinal column of Wister rats is also found not to reveal any inflammatory response after the implantation. Granuloma and material debris is found to be absent in all three periods of implantation in both test and control. No necrosis was observed around the implanted materials, which were found to be encapsulated by fibrous connective tissue consisting of predominantly fibroblasts and inflammatory cells. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Curing behaviors and properties of novolac/bisphthalonitrile blends
Authors: Guo Heng , Lei Yajie , Zhao Xin , Yang Xulin , Zhao Rui , Liu Xiaobo
Published: December 2011

Bisphthalonitrile (BAPh) monomer was blended with novolac resins to achieve good processing resin blends. The curing behaviors of the novolac/BAPh (novolac/BAPh) blends were studied by differential scanning calorimetry (DSC) and dynamic rheological analysis. The results indicated that the blends had large processing windows (98–118°C), and they can copolymerize without any other curing additives. The novolac/BAPh copolymers were obtained by short curing times and low curing temperatures. Thermal and thermal‐oxidative stabilities of the copolymers were investigated by thermal gravimetric analysis, and the char yields up to 74 and 35% by weight at 800°C were achieved under nitrogen and air atmosphere, respectively. These postcured copolymers exhibited a 5% weight loss temperature of 502°C in air. These results revealed that the copolymers exhibited excellent thermal and thermal‐oxidative stabilities. Dynamic mechanical properties of the copolymers were systematically evaluated by dynamic mechanical analysis. The copolymers exhibited higher glass transition temperatures (Tg) as the BAPh content increased. Mechanical properties of the copolymers were investigated, and these data showed that flexural strength and flexural modulus of the 50 : 50 novolac/BAPh copolymers were 91 MPa and 5.78 GPa, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Molecular Mechanism of Remodeling of Autologous Artery Graft Interposed to Vein in Rabbit
Authors: Feng Yanling , Shen Yanguo , Zhang Hongqi
Published: December 2011

Our previous study found that the artery interposed to vein did not develop atherosclerosis but rather underwent atrophic remodeling in hyperlipidemic rabbits, suggesting that local hemodynamic load was another important determinant for the development of atherosclerosis. This study focused on the cellular and molecular changes in autologous artery grafts derived from rabbits fed with high lipid diet for 1, 2, 4, 8, and 12 weeks. Thickness, area of vessel wall, and lumen area were measured and analyzed on the grafted common carotid artery (GCCA) interposed to vein and on the right common carotid artery. Apoptosis was detected by terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end‐labeling. Both elastin and collagen of GCCA were identified by the method of double stains of elastin and collagen. Reverse transcription polymerase chain reaction was used to observe matrix metalloproteinases (MMPs) mRNA expression changes in the examined arteries. The lumen area increased gradually in control common carotid artery and remained unchanged in GCCA 3 months later, since the surgery and the start of high lipid diet, while significantly increased apoptosis was evidenced from inner to outer part of GCCA. Collagen content decreased gradually and elastic fibers remained unchanged in GCCA. At 1 week after operation, the mRNA expression of MMP2 and MMP9 increased significantly and returned to baseline thereafter. The artery interposed to a vein underwent atrophy, characterized by increased apoptosis in the vessel wall from intima to adventitia, possibly due to low shear stress circumference and reduced vessel collagen resulting from postsurgical upregulated MMP2 and MMP9 expression. Anat Rec,, 2012. © 2011 Wiley Periodicals, Inc.
Risk factors for magnetic resonance imaging–detected patellofemoral and tibiofemoral cartilage loss during a six‐month period: The Joints On Glucosamine study
Authors: Roemer Frank W. , Kwoh C. Kent , Hannon Michael J. , Green Stephanie M. , Jakicic John M. , Boudreau Robert , Crema Michel D. , Moore Carolyn E. , Guermazi Ali
Published: December 2011

Objective

To assess several baseline risk factors that may predict patellofemoral and tibiofemoral cartilage loss during a 6‐month period.

Methods

For 177 subjects with chronic knee pain, 3T magnetic resonance imaging (MRI) of both knees was performed at baseline and followup. Knees were semiquantitatively assessed, evaluating cartilage morphology, subchondral bone marrow lesions, meniscal morphology/extrusion, synovitis, and effusion. Age, sex, and body mass index (BMI), bone marrow lesions, meniscal damage/extrusion, synovitis, effusion, and prevalent cartilage damage in the same subregion were evaluated as possible risk factors for cartilage loss. Logistic regression models were applied to predict cartilage loss. Models were adjusted for age, sex, treatment, and BMI.

Results

Seventy‐nine subregions (1.6%) showed incident or worsening cartilage damage at followup. None of the demographic risk factors was predictive of future cartilage loss. Predictors of patellofemoral cartilage loss were effusion, with an adjusted odds ratio (OR) of 3.5 (95% confidence interval [95% CI] 1.3–9.4), and prevalent cartilage damage in the same subregion with an adjusted OR of 4.3 (95% CI 1.3–14.1). Risk factors for tibiofemoral cartilage loss were baseline meniscal extrusion (adjusted OR 3.6 [95% CI 1.3–10.1]), prevalent bone marrow lesions (adjusted OR 4.7 [95% CI 1.1–19.5]), and prevalent cartilage damage (adjusted OR 15.3 [95% CI 4.9–47.4]).

Conclusion

Cartilage loss over 6 months is rare, but may be detected semiquantitatively by 3T MRI and is most commonly observed in knees with Kellgren/Lawrence grade 3. Predictors of patellofemoral cartilage loss were effusion and prevalent cartilage damage in the same subregion. Predictors of tibiofemoral cartilage loss were prevalent cartilage damage, bone marrow lesions, and meniscal extrusion.
Sunitinib inhibits the phosphorylation of platelet‐derived growth factor receptor β in the skin of mice with scleroderma‐like features and prevents the development of the disease
Authors: Kavian Niloufar , Servettaz Amélie , Marut Wioleta , Nicco Carole , Chéreau Christiane , Weill Bernard , Batteux Frédéric
Published: December 2011

Objective

Systemic sclerosis (SSc) is characterized by fibrosis of the skin and visceral organs, vascular dysfunction, and immunologic dysregulation. Platelet‐derived growth factors (PDGFs) have been implicated in the development of fibrosis and dysregulation of vascular function. We investigated the effects of sunitinib and sorafenib, two tyrosine kinase inhibitors that interfere with PDGF signaling, in a mouse model of diffuse SSc.

Methods

SSc was induced in BALB/c mice by subcutaneous injections of HOCl daily for 6 weeks. Mice were randomized to treatment with sunitinib, sorafenib, or vehicle. The levels of native and phosphorylated PDGF receptor β (PDGFRβ) and vascular endothelial growth factor receptor (VEGFR) in the skin were assessed by Western blot and immunohistochemical analyses. Skin and lung fibrosis were evaluated by histologic and biochemical methods. Autoantibodies were detected by enzyme‐linked immunosorbent assay, and spleen cell populations were analyzed by flow cytometry.

Results

Phosphorylation of PDGFRβ and VEGFR was higher in fibrotic skin from HOCl‐injected mice with SSc than from PBS‐injected mice. Injections of HOCl induced cutaneous and lung fibrosis, increased the proliferation rate of fibroblasts in areas of fibrotic skin, increased splenic B cell and T cell counts, and increased anti–DNA topoisomerase I autoantibody levels in BALB/c mice. All of these features were reduced by sunitinib but not by sorafenib. Sunitinib significantly reduced the phosphorylation of both PDGF and VEGF receptors.

Conclusion

Inhibition of the hyperactivated PDGF and VEGF pathways by sunitinib prevented the development of fibrosis in HOCl‐induced murine SSc and may represent a new SSc treatment for testing in clinical trials.
Assessments of growth conditions on the production of cyanophycin by recombinant Escherichia coli strains expressing cyanophycin synthetase gene
Authors: Tseng Wen‐Chi , Fang Tsuei‐Yun , Cho Chiung‐Yu , Chen Po‐Shao , Tsai Ching‐Shiang
Published: December 2011

The synthesis of cyanophycin, a biodegradable polymer, is directed by cyanophycin synthetase. Polymerase chain reaction (PCR) cloned the gene cphA coding for cyanophycin synthetase from Synechocystis sp. PCC 6803 into pET‐21b followed by transformation into two Escherichia coli hosts. The culture conditions for cyanophycin production were investigated, and the molecular weight and compositions of purified cyanophycin were analyzed. The results showed that E. coli BL21‐CodonPlus(DE3)‐RIL could produce 120 mg cyanophycin per gram dry cell weight in terrific medium. The purified cyanophycin consisted of insoluble and soluble forms at pH 7. The insoluble form had a higher molecular weight (20–32 kDa) than the soluble form (14–25 kDa). Both forms are composed of three major amino acids, aspartic acid, arginine, and lysine, and the insoluble form showed a higher arginine/lysine molar ratio (4.61 ± 0.31) than the soluble form (0.89 ± 0.05). In addition, the nitrogen sources could affect the yields of insoluble and soluble forms of cyanophycin. The medium containing additional lysine could enhance the proportion of the soluble form, but had little effect on the lysine and arginine percentages of both soluble and insoluble forms. The medium containing additional arginine slightly decreased the proportion of soluble form and altered its amino acid composition, with a minimal effect on the lysine and arginine percentages in the insoluble form. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Eliminating the six N‐terminal amino acids of the caspase 3 large subunit improved production of a biologically active IL2‐Caspase3 chimeric protein
Authors: Glantz Yitav , Sabag Ofra , Lichtenstein Michal , Grodzovski Inna , Lorberboum‐Galski Haya
Published: December 2011

Designing a chimeric protein and developing a procedure for its stable production as a biologically active protein, are key steps in its potential application to clinical trails. IL2‐Caspase3 chimeric protein designed to target activated T lymphocytes was found to be a promising molecule for targeted treatment, however was found to be difficult to produce as a biological active molecule. Thus, we designed a new version of the molecule, IL2‐Caspase3s, in which six amino acids (aa 29–34) from the N‐terminus of the large subunit of caspase 3 were excluded. Repeated expressions, productions, and partial purifications of the IL2‐Caspase3s yielded reproducible batches with consistent results. We found that IL2‐Caspase3s causes cell death in a specific, dose‐, and time‐dependent manner. Cell death due to IL2‐Caspase3s is caused by apoptosis. This improved and biologically stable IL2‐Caspase3s chimeric protein may be developed in the future for clinical trails as a promising therapy for several pathologies involving activated T‐cells. Moreover, this truncated caspase 3 sequence, lacking the N‐terminal six amino acids of its large subunit, may be used in other caspase 3‐based chimeric proteins targeted against various human diseases, using the appropriate targeting moiety. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Development of FRET‐Based Dual‐Excitation Ratiometric Fluorescent pH Probes and Their Photocaged Derivatives
Authors: Yuan Lin , Lin Weiying , Cao Zengmei , Wang Jiaoliang , Chen Bin
Published: December 2011

Dual‐excitation ratiometric fluorescent probes allow the measurement of fluorescence intensities at two excitation wavelengths, which should provide a built‐in correction for environmental effects. However, most of the small‐molecule dual‐excitation ratiometric probes that have been reported thus far have shown rather limited separation between the excitation wavelengths (20–70 nm) and/or a very small molar absorption coefficient at one of the excitation wavelengths. These shortcomings can lead to cross‐excitation and thus to errors in the measurement of fluorescence intensities and ratios. Herein, we report a FRET‐based molecular strategy for the construction of small‐molecule dual‐excitation ratiometric probes in which the donor and acceptor excitation bands exhibit large separations between the excitation wavelengths and comparable excitation intensities, which is highly desirable for determining the fluorescence intensities and signal ratios with high accuracy. Based on this strategy, we created a coumarin–rhodamine FRET platform that was then employed to develop the first class of FRET‐based dual‐excitation ratiometric pH probes that have two well‐resolved excitation bands (excitation separations>160 nm) and comparable excitation intensities. In addition, these pH probes may be considered as in a kind of “secured ratioing mode”. As a further application of these pH probes, the dual‐excitation ratiometric pH probes were transformed into the first examples of photocaged dual‐excitation ratiometric pH probes to improve the spatiotemporal resolution. It is expected that the modular nature of our FRET‐based molecular strategy should render it applicable to other small‐molecule dual‐dye energy‐transfer systems based on diverse fluorescent dyes for the development of a wide range of dual‐excitation ratiometric probes with outstanding spectral features, including large separations between the excitation wavelengths and comparable excitation intensities.
A Versatile Thiouronium‐Based Solid‐Phase Synthesis of 1,3,5‐Triazines
Authors: Kong Kah Hoe , Tan Chong Kiat , Lin Xijie , Lam Yulin
Published: December 2011

A thiouronium‐based solid‐phase synthesis of a 1,3,5‐triazine scaffold has been developed. The key feature of the synthesis is the use of a readily accessible solid‐supported thiouronium salt as a primary precursor for the stepwise assembly of the 1,3,5‐triazine substrate. The sulfur linker employed in the synthesis is stable under both acidic and basic conditions and is versatile enough to provide access to monocyclic, bicyclic, and spirocyclic compounds with the 1,3,5‐triazine scaffold. By using this synthetic strategy, a representative set of 79 compounds containing the 1,3,5‐triazine scaffold were prepared.
Study of pressure fluctuations in an internal loop airlift bioreactor
Authors: Luo Lijia , Yan Ying , Xu Yuanyuan , Xie Ping , Sun Junwei , Guo Wei , Yuan Jingqi
Published: December 2011

The origin and coupling of pressure fluctuations in an internal loop airlift bioreactor are investigated. The pressure fluctuations in the reactor are divided into two categories: global pressure fluctuations and local pressure fluctuations. It is found that the coupling between global pressure fluctuations and local pressure fluctuations mainly focuses in the frequency region between 10 and 30 Hz. Local pressure fluctuations in the reactor are strongly affected by pressure waves originating from the air‐supply system, while pressure fluctuations caused by the bubble eruption at the liquid surface have less influence on local pressure fluctuations. Based on the coherence analysis, the pressure signal at a certain position in the reactor is decomposed into three different parts: coherent part, joint incoherent part and exclusive incoherent part. The energy ratios of these different parts are helpful to study the interaction among pressure fluctuations from different sources. Three flow regimes were identified from the evolution of the energy ratio of the joint incoherent part. © 2011 Canadian Society for Chemical Engineering
Design of a micro glass cell apparatus for pure gas‐nonvolatile liquid phase behaviour study
Authors: Foroughi Hooman , Acosta Edgar J. , Kawaji Masahiro
Published: December 2011

A micro syringe is used as a constant volume cell for gas–liquid equilibrium (GLE) study. The cell is made of glass and has a volume of <100 µL. It can operate at pressures up to 13 MPa and temperatures up to 115°C. Two different experimental procedures are presented for systems with nonvolatile low and high viscosity liquids. A micro magnetic stir bar is used to mix the gas–liquid mixtures inside the cell. Since the internal volume of the cell is small, a short mixing time is sufficient for the gas–liquid mixtures to reach equilibrium. The solubility values are measured by using the pressure decay method. The experimental procedures are validated by measuring the carbon dioxide (CO2) solubility in water and highly viscous bitumen. The experimental results are in good agreement with the available literature data which shows that the technique works well. © 2011 Canadian Society for Chemical Engineering
Development of kerosene–water two‐phase up‐flow in a vertical pipe downstream of A 90° bend
Authors: Hamad F. A. , He S. , Khan M. K. , Bruun H. H.
Published: December 2011

The development of kerosene–water up‐flow in a vertical pipe of 77.8 mm inner diameter and 4500 mm, length downstream of a 90° bend, has been investigated using a Pitot tube and dual optical probe. The CFD ANSYS Fluent 12.0 is used to model the flow and the results are compared with experimental data. The CFD provides detailed information on flow structure which is difficult to obtain in experiments. The experimental measurements of the local parameters demonstrate that the single phase and two‐phase flows reached the fully developed axisymmetrical conditions at L/D = 54. These results also show the severe asymmetry distributions of the two‐phase flow parameters at the entrance region (L/D = 1). The predictions from Fluent are found to be in close agreement with experimental data for L/D ≥ 16 but there is a significant discrepancy at L/D = 1. © 2011 Canadian Society for Chemical Engineering