bluuebunny/crossref_metadata_2025_split huggingface dataset:
The impact of fallback foods on wild ring‐tailed lemur biology: A comparison of intact and anthropogenically disturbed habitats
Authors: Sauther Michelle L. , Cuozzo Frank P. 
Published: November 2009

AbstractFallback foods are often viewed as central in shaping primate morphology, and influencing adaptive shifts in hominin and other primate evolution. Here we argue that fruit of the tamarind tree (Tamarindus indica) qualifies as a fallback food of ring‐tailed lemurs (Lemur catta) at the Beza Mahafaly Special Reserve (BMSR), Madagascar. Contrary to predictions that fallback foods may select for dental and masticatory morphologies adapted to processing these foods, consumption of tamarind fruit by these lemurs leaves a distinct pattern of dental pathology among ring‐tailed lemurs at BMSR. Specifically, the physical and mechanical properties of tamarind fruit likely result in a high frequency of severe tooth wear, and subsequent antemortem tooth loss, in this lemur population. This pattern of dental pathology is amplified among lemurs living in disturbed areas at Beza Mahafaly, resulting from a disproportionate emphasis on challenging tamarind fruit, due to few other fruits being available. This is in part caused by a reduction in ground cover and other plants due to livestock grazing. As such, tamarind trees remain one of the few food resources in many areas. Dental pathologies are also associated with the use of a nonendemic leaf resource Argemone mexicana, an important food during the latter part of the dry season when overall food availability is reduced. Such dental pathologies at Beza Mahafaly, resulting from the use or overemphasis of fallback foods for which they are not biologically adapted, indicate that anthropogenic factors must be considered when examining fallback foods. Am J Phys Anthropol 140:671–686, 2009. © 2009 Wiley‐Liss, Inc.
Numerical simulation of aggregate dispersion in different flow fields using discrete element method
Authors: Hosseini M. Salami , Nazockdast H. , Dabir B. 
Published: November 2009

AbstractAn attempt was made to study the aggregate dispersion process in three different flow fields namely; steady shear, elongation flow, and combined shear and elongational flows using the discrete element method. The simulation was performed on two aggregate structures characterized by their fractal dimensions. The predicted results showed that the aggregate break‐up process evaluated in terms of weighted average fragment size 〈w〉 follows a power–law type relation as 〈w〉 = kt−m in all the three flow fields. The dispersion performance of different flow fields evaluated by dispersing rate and a final steady‐state fragment size was found to be dependent upon the extent of applied stress and flow fields such that at low applied stress levels much smaller steady state values of 〈w〉 could be obtained for the elongational flow. The aggregate structure, characterized by its fractal dimension, was found to have different effects on the aggregate dispersion process depending on the flow field and applied stress level. The results predicted from this simulation could be explained in terms of ability of flow fields in rotating the aggregates and fragments in appropriate position to be broken up and the fractal dimensions of aggregates. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Isotactic polypropylene composites reinforced with multiwall carbon nanotubes, part 2: Thermal and mechanical properties related to the structure
Authors: Kotsilkova Rumiana , Ivanov Evgeni , Krusteva Ekaterina , Silvestre Clara , Cimmino Sossio , Duraccio Donatella 
Published: November 2009

AbstractPolypropylene nanocomposites containing multiwall carbon nanotubes (MWCNT), from 0.1 to 3 wt %, are prepared by dilution of a polypropylene based masterbatch (20% MWCNT) with isotactic polypropylene (iPP) using extrusion processing. CNT are found to enhance significantly the thermal stability of iPP in nitrogen and air atmosphere. Dynamic mechanical analysis and tensile tests confirm the reinforcement effect of small amount of nanotubes in iPP. Rheology, structure, and properties are correlated determine the optimal limits of nanofiller content required for improving the performance of nanocomposites. The rheological flocculation threshold of φ* = 0.5% is found as a critical concentration for the formation of a flocculated type of structure in the dispersions. It is proposed, that the flocculated structure is responsible for the maximal improvement of nanocomposite mechanical and thermal properties. The MWCNT additive slightly enhances the local dynamics of iPP molecules in the glass transition region and suppresses the global relaxation of the chain segments in the amorphous regions, resulting in a reinforcement effect. The fracture mechanism is discussed and associated with the hierarchy of the flocculated nanocomposite morphology and the bridging of matrix cracks by CNT. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of in situ surface‐modified nano‐SiO2 on the thermal and mechanical properties and crystallization behavior of nylon 1010
Authors: Xiuwei Fang , Xiaohong Li , Laigui Yu , Zhijun Zhang 
Published: November 2009

AbstractNylon 1010 composites filled with two types of surface‐modified SiO2 nanoparticles (RNS and DNS) were prepared by melt blending. The mechanical properties of the composites were evaluated. The influences of the surface‐modified nano‐SiO2 on the thermal stability, crystallization behavior, and microstructure of nylon 1010 were investigated by thermogravimetric analysis, differential scanning calorimetry (DSC), X‐ray diffraction, and transmission electron microscopy. And the interfacial interactions between the fillers and polymer matrix were examined using a Fourier transformation infrared spectrometer. It was found that the addition of the surface‐modified nano‐SiO2 had distinct influences on the thermal stability, mechanical properties, and crystallization behavior of nylon 1010. RNS and DNS as the fillers had different effects on the mechanical properties of nylon 1010. The composites filled with RNS at a mass fraction of 1–5% showed increased break elongation, Young's modulus, and impact strength but almost unchanged or even slightly lowered tensile strength than the unfilled matrix. The DNS‐filled nylon 1010 composites had obviously decreased tensile strength, whereas the incorporation of DNS also contributed to the increase in the Young's modulus of nylon 1010, but less effective than RNS. Moreover, the nylon 1010 composites had better thermal stability than the neat polymer matrix, and the composites filled with RNS were more thermally stable than those filled with DNS. The difference in the crystallinity of neat nylon 1010 and its composites filled with RNS and DNS was subtle, although the surface‐modified nano‐SiO2 could induce or/and stabilize the γ‐crystalline formation of nylon 1010. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Novel methyl cellulose‐grafted‐acrylamide/gelatin microspheres for controlled release of nifedipine
Authors: Babu V. Ramesh , Kanth V. Rajinee , Mukund Jadhav M. , Aminabhavi Tejraj M. 
Published: November 2009

AbstractNaturally available carbohydrate polymers such as methylcellulose (MC) and gelatin (Ge) have been widely studied in the previous literature for controlled release (CR) applications. In this study, methyl cellulose‐g‐acrylamide/gelatin (MC‐g‐AAm/Ge) microspheres were prepared by water‐in‐oil (W/O) emulsion method and crosslinked with glutaraldehyde to encapsulate with nifedipine (NFD), an antihypertensive drug. The microspheres prepared were characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and laser particle size analyzer. DSC thermograms of NFD‐loaded AAm‐MC/Gel microspheres confirmed the molecular level distribution of NFD in the matrix. SEM indicated the formation of spherical particles. Swelling experiments supported the drug diffusion characteristics and release data of the matrices. Cumulative release data were analyzed using an empirical equation to understand the nature of transport of drug through the matrices. Controlled release characteristics of the matrices for NFD were investigated in pH 7.4 media. Drug was released in a controlled manner up to 12 h. Particle size and size distribution of the microspheres as studied by laser light diffraction particle size analyzer indicated their sizes to be around 120 μm. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Investigation of factors affecting synthesis of polyvinyl butyral by Taguchi method
Authors: Hajian Morteza , Koohmareh Gholam Ali , Rastgoo Mahdi 
Published: November 2009

AbstractPolyvinyl butyral (PVB) was prepared by condensation reaction of butyral with polyvinyl alcohol (PVA) in aqueous phase containing an acid as a catalyst and an emulsifying agent. Properties of the polymer were a function of the relative amounts of the three randomly distributed units of acetal, acetate and vinyl alcohol groups, and the molecular weight. In this work, some effective factors in synthesis of PVB have been investigated by Taguchi method. The percent of the acetalization has been determined according to the ASTM D1396, and the polymer was characterized by IR, TG, and DTG techniques. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Surface chemical modification of polypropylene fiber waste by H2SO4: Mechanistic investigation and application as cation‐exchange adsorbent
Authors: Matos Jamerson Peixoto , Sansiviero Maria Terezinha Caruzo , Lago Rochel Montero 
Published: November 2009

AbstractIn this work, polypropylene (PP) fiber waste was modified by the reaction with concentrated H2SO4. IR, TG, Raman, CHN, acid titration, SEM, and XRD suggested that sulfuric acid at about 105°C reacts with PP to produce mainly surface sulfonic groups. The kinetic experiments showed that these SO3H groups decompose to form SO2 gas leading to an aromatization of the polymer to form amorphous and graphitic carbon. Adsorption isotherms of the cationic model molecule methylene blue showed that the modified PP fibers have a great potential as ion‐exchange adsorbent. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and characterization of biodegradable thermoplastic films based on collagen hydrolyzate
Authors: Haroun A. A. 
Published: November 2009

AbstractThe increasing use of plastics and their nonbiodegradability have raised environmental awareness and hence there is a need for the development of environmentally friendly degradable materials. One of the ways to reach this goal is via the modification of the synthetic polymer, modified polyethylene (MPE), with protein, collagen hydrolyzate (CH). CH is a biopolymer isolated from hide/skin fleshing of untanned solid waste from the leather industry after enzymatic hydrolysis. An investigation on the blending of MPE with CH using polymer melt technique is reported. The resulting thermoplastic films were evaluated using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA/DTA), and scanning electron microscope (SEM), in addition to simulated soil burial respirometric testing. It is interesting to note that CH easily blends with MPE, but like other biopolymers, it also has effects on the original mechanical properties of the MPE. The CH addition in the blend significantly increases the biodegradation rate. The effect of CH on MPE biodegradability has been investigated. About 53% biodegradation is observed, after 24 days, when the polymer is blended with 5% CH and about 63% biodegradation is found in the case of polymer blended with 20% CH. Although MPE/CH thermoplastic film with 40% CH have shown better performance in biodegradation, the mechanical strength properties were rather poor in this case. The optimum thermoplastic film composition for blending of CH with MPE is about 10–20 wt % CH, which retains an acceptable range of compatibility, mechanical strength, and biodegradability. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Polyamide 6 composites reinforced with silicon nitride whiskers: Synthesis, interface interaction, and mechanical properties
Authors: Li Lanjie , Yang Guisheng 
Published: November 2009

AbstractIn this study, polyamide 6 (PA6)/silicon nitride whisker (SNW) composites were fabricated via in situ hydrolytic ring‐opening polymerization of ε‐caprolactam. By this novel method, SNWs can be dispersed uniformly in PA6 matrix. The interface interaction between SNW and PA6 was investigated, and the reinforcing efficiency of SNW on PA6 was evaluated. It was revealed by Fourier transform infrared spectroscopy that a large amount of polar groups, such as SiOH, NH, and NH2, were present on the SNWs, by which hydrogen bonding and covalent bonding can be formed at interface. Mechanical test showed that at a loading of 5.0 wt % SNW, the tensile strength, tensile modulus, flexural strength, flexural modulus, and impact strength of PA6/SNW composite were 37.9, 80.5, 60.3, 73.9, and 64% higher than those of neat PA6, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Controlled release of carbamazepine from carboxymethyl chitosan‐grafted‐ 2‐hydroxyethylmethacrylate matrix tablets
Authors: Patel Nirmal K. , Joshi Jigar , Mishra Deepak , Patel Vishnu A. , Sinha Vijay Kumar 
Published: November 2009

AbstractThe aim of the study was to prepare the controlled release dosage of carbamazepine matrix tablets using wet granulation technique. The graft copolymerization of carboxymethyl chitosan (CMCH) with 2‐hydroxyethylmethacrylate (HEMA) was carried out. The product was characterized by Fourier‐transform infrared, scanning electron microscopy, transmission electron micrograph, and X‐ray diffraction anayses. CMCH‐g‐HEMA was used as binder to prepare the matrix tablets containing carbamazepine. The properties of tablets like hardness, friability, and dissolution influenced by binder were studied. In vitro release of the matrix tablets was carried out with the phosphate‐buffered solution (pH 7.4) at 37°C and 100 × g using USP dissolution test apparatus. Release rate of carbamazepine from controlled release matrix tablets was compared with the commercially marketed tablet, Tagretol 200. Results show that after 6 hrs percentage drug release of formulated tablet CGH5 was 20.42% and that of Tegretol 200 was 18.32%. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Hydrogels from scleroglucan and ionic crosslinkers: Characterization and drug delivery
Authors: Coviello Tommasina , Matricardi Pietro , Balena Alessandra , Chiapperino Bicemaria , Alhaique Franco 
Published: November 2009

AbstractThe polysaccharide scleroglucan (Sclg), exploited as a matrix suitable for modified drug delivery, was crosslinked in the presence of three ions: borate, aluminum, and iron. A rheological investigation indicated the main differences between the hydrogels in their viscoelastic linear response: the Sclg/borax system showed the highest strength when deformed by elongation, whereas the strength of the other systems broke down, in terms of viscosity, at much lower values of the imposed strain. Tablets prepared from the gels showed remarkable differences in their water uptake and dimensional swelling. On the other hand, the tablets, loaded with drugs of different steric hindrances, showed similar release behavior, regardless of the crosslinking agent. Scanning electron microscopy analysis was related to the delivery and rheological profiles. Texture analysis, carried out on tablets swollen for 5 h, showed different values of cohesion. Furthermore, when the generalized Maxwell model was applied to the relaxation data, the obtained mechanical spectra showed a more pronounced solidlike character of the Sclg/iron network in comparison with the prevailing viscous behavior of the other matrices. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Direct‐current and alternating‐current analysis of the humidity‐sensing properties of nickel oxide doped polypyrrole encapsulated in mesoporous silica SBA‐15
Authors: Wang Rui , Zhang Tong , He Yuan , Li Xiaotian , Geng Wangchang , Tu Jinchun , Yuan Qing 
Published: November 2009

AbstractNickel oxide (NiO) doped polypyrrole (PPy) was encapsulated in mesoporous SBA‐15. All of the synthesized samples were characterized by infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy. They were investigated as humidity‐sensor materials at room temperature. The sensor showed excellent humidity sensitivity in the relative humidity range 11–95%. The humidity‐sensing properties were very much improved by encapsulation of the NiO‐doped PPy into mesoporous silica SBA‐15. Finally, the sensitivity mechanism was investigated by direct‐current (dc) and alternating‐current (ac) analysis. The dc circuit with the instantaneous polarity reversion method was designed by us to study the dc response in different humidity environments. The conductive mechanism was established through the dc and ac investigation, and the conductive particles were identified as ions and electrons. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of spinning conditions on the mechanical properties of polyacrylonitrile fibers modified with carbon nanotubes
Authors: Mikolajczyk T. , Szparaga G. , Bogun M. , Fraczek‐Szczypta A. , Blazewicz S. 
Published: November 2009

AbstractCarbon nanotubes (CNTs) were used to modify polyacrylonitrile (PAN) polymer. The PAN/CNT composite fibers were spun from dimethylformamide solutions containing different types of CNTs. The effect of nanotube addition to the fiber precursor on the resulting mechanical properties is discussed. In this study, we examined the relationship of the rheological properties of PAN spinning solutions containing various types of CNTs and the tensile strength of the resulting PAN fibers. The presence of CNTs in the PAN spinning solution enhanced its deformability during the drawing stage. This effect resulted in a higher tensile strength in the fibers containing nanotubes, as compared to the pure fibers. The use of a three‐stage drawing process resulted in a significant increase in the tensile strength of PAN fibers modified with multiwalled nanotubes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of silane‐grafting on water tree resistance of XLPE cable insulation
Authors: Ma Zhishen , Huang Xingyi , Jiang Pingkai , Wang Genlin 
Published: November 2009

AbstractWater treeing is one of the main deterioration phenomena observed in the polymeric insulation of extruded crosslinked polyethylene (XLPE) cables, which can affect the service life of power cables. In this work, we investigated the effect of grafting of a silane (vinyl trimethoxysilane, VTMS) on the resistance of XLPE to water treeing. A series of water‐treeing tests, the mechanical and dielectric measurements indicated that the silane‐grafting could significantly improve the water tree resistance of the conventional XLPE cable insulation with little influences on its dielectric properties, e.g., the dielectric breakdown strength, dielectric constant and loss tangent, and its mechanical performance. It was found that there exists an optimum value of VTMS concentration (about 0.6 phr) corresponding to the minimum water tree length. The water tree resistance mechanism of silane‐grafted XLPE was proposed on the basis of the process of silane hydrolysis and crosslinking. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A head in virtual reality: Development of a dynamic head and neck model
Authors: Nguyen Ngan , Wilson Timothy D. 
Published: November 2009

AbstractAdvances in computer and interface technologies have made it possible to create three‐dimensional (3D) computerized models of anatomical structures for visualization, manipulation, and interaction in a virtual 3D environment. In the past few decades, a multitude of digital models have been developed to facilitate complex spatial learning of the human body. However, there is limited empirical evidence to guide the development and integration of effective computer models for teaching and learning. The purpose of this article is to describe the development of a dynamic head and neck model with flexible displays (2D, 3D, and stereoscopic 3D) and interactive control features that can be later used to design and test the efficacy of computer models as a means of improving student learning. The model was created using computer tomography scans of a human cadaver. Anatomical structures captured on the scans were segmented into discreet areas, and then reconstructed in three‐dimensions using specialized software. The final model consists of 70 distinct anatomical structures that can be displayed in 2D, 3D, or stereoscopic 3D. In 3D mode, a mouse can be used to actively and continuously interact with the model by manipulating viewer orientation, altering surface transparency, superimposing 2D scans with 3D reconstructions, removing or adding structures sequentially, and customizing animated scenes to show complex anatomical pathways or relationships. Anat Sci Educ 2: 294–301, 2009. © 2009 American Association of Anatomists.
Medical education in the anatomical sciences: The winds of change continue to blow
Authors: Drake Richard L. , McBride Jennifer M. , Lachman Nirusha , Pawlina Wojciech 
Published: November 2009

AbstractAt most institutions, education in the anatomical sciences has undergone several changes over the last decade. To identify the changes that have occurred in gross anatomy, microscopic anatomy, neuroscience/neuroanatomy, and embryology courses, directors of these courses were asked to respond to a survey with questions pertaining to total course hours, hours of lecture, and hours of laboratory, whether the course was part of an integrated program or existed as a stand‐alone course, and what type of laboratory experience occurred in the course. These data were compared to data obtained from a similar survey in 2002. Comparison between the data sets suggests several key points some of which include: decreased total hours in gross anatomy and neuroscience/neuroanatomy courses, increased use of virtual microscopy in microscopic anatomy courses, and decreased laboratory hours in embryology courses. Anat Sci Educ 2: 253–259, 2009. © 2009 American Association of Anatomists.
Dust‐enshrouded star formation in XMM‐LSS galaxy clusters
Authors: Temporin S. , Duc P.‐A. , Ilbert O. , XMM‐LSS/SWIRE collaboration  
Published: November 2009

AbstractIn recent years, infrared studies of individual galaxy clusters at intermediate redshifts led to the identification of several luminous infrared galaxies (LIR > 1011 L⊙). These findings were interpreted as an evidence ofvigorous, dust‐enshrouded star formation activity, hinting at the presence of an infrared Butcher‐Oemler effect. In order to explore this effect, we have undertaken a statistical investigation based on a cluster sample drawn from the XMM‐Newton Large Scale Structure survey (XMM‐LSS) and exploiting the contiguous coverage of the XMM‐LSS field by the Spitzer SWIRE legacy survey. We adopted a stacking technique to investigate the distribution of 24‐μ m sources out to the cluster periphery and compare it with the distribution of sources in a sample of control fields. Among putative cluster members, selected by means of photometric redshifts, we identified surprisingly high numbers of bright 24‐μ m sources toward intermediate redshift clusters (z > 0.3). Our analysis indicates the presence of an excess of bright mid‐IR sources at redshift z > 0.3 at clustercentric radii ∼200–500 kpc (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)