bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical activity in an indigenous Ecuadorian forager‐horticulturalist population as measured using accelerometry
Authors: Madimenos Felicia C. , Snodgrass J. Josh , Blackwell Aaron D. , Liebert Melissa A. , Sugiyama Lawrence S. 
Published: April 2011

AbstractObjective:Minimal information on physical activity is available for non‐Western populations undergoing the transition to a market economy. This is unfortunate given the importance of these data for understanding health issues such as the global obesity epidemic. We consider the utility of using accelerometry technology to examine activity patterns and energy use regulation among indigenous Shuar, an Ecuadorian forager‐horticulturalist population undergoing economic and lifestyle change. We investigate sex differences in Shuar activity patterns and the effects of reproductive status on activity. Finally, we discuss the potential of accelerometry use in human biology research.Methods:Physical activity levels were measured using Actical accelerometers in 49 indigenous Shuar adults (23 males, 26 females) from a rural Ecuadorian community. Female participants were in various reproductive states including pregnant, lactating, and nonpregnant/nonlactating.Results:Activity counts (AC), activity energy expenditure (AEE), and physical activity levels (PAL) were significantly higher (P < 0.05) in males than females. Significant differences in energy expenditure were found among pregnant or lactating females and males with pregnant or lactating partners (P < 0.001). Males with pregnant or lactating partners also had significantly higher activity levels than did other men (P < 0.01).Conclusions:Shuar activity levels are relatively low compared to other non‐Western populations. Despite increasing market integration, pregnant and lactating females seem to be adopting a strategy noted in other subsistence populations where male participation in subsistence activities increases to compensate for their partners' elevated reproductive costs. Despite certain limitations, use of accelerometry in human biology research shows promise. Am. J. Hum. Biol. 2011. © 2011 Wiley‐Liss, Inc.
Lowland origin women raised at high altitude are not protected against lower uteroplacental O2 delivery during pregnancy or reduced birth weight
Authors: Julian Colleen G. , Hageman Jennifer L. , Wilson Megan J. , Vargas Enrique , Moore Lorna G. 
Published: April 2011

AbstractObjective.Maternal physiologic responses to pregnancy promoting fetal oxygen and nutrient delivery are important determinants of reproductive success. Incomplete physiologic compensation for reduced oxygen availability at high altitude (≥2,500 m) compromises fetal growth. Populations of highland (e.g., Andeans, Tibetans) compared with lowland origin groups (e.g., Europeans, Han Chinese) are protected from this altitude‐associated decrease in birth weight; here we sought to determine whether maternal development at high altitude—rather than highland ancestry—contributed to the protection of birth weight and uterine artery (UA) blood flow during pregnancy.Methods.In women of lowland ancestry who were either raised at high altitude in La Paz, Bolivia (3,600–4,100 m) (“lifelong,” n = 18) or who had migrated there as adults (“newcomers,” n = 40) we compared maternal O2 transport during pregnancy and their infant's birth weight.Results.Pregnancy raised maternal ventilation and arterial O2 saturation equally, with the result that arterial O2 content was similarly maintained at nonpregnant levels despite a fall in hemoglobin. UA blood flow and uteroplacental O2 delivery were lower in lifelong than newcomer residents (main effect). Birth weight was similar in lifelong residents versus newcomers (2,948 ± 93 vs. 3,090 ± 70 gm), with both having values below those of a subset of eight high‐altitude residents who descended to deliver at low altitude (3,418 ± 133 gm, P < 0.05).Conclusion.Lifelong compared with newcomer high‐altitude residents have lower uteroplacental O2 delivery and similar infant birth weights, suggesting that developmental factors are likely not responsible for the protective effect of highland ancestry. Am. J. Hum. Biol. 2011. © 2011 Wiley‐Liss, Inc.
Making and Breaking Peptide Bonds: Protein Engineering Using Sortase
Authors: Popp Maximilian Wei‐Lin , Ploegh Hidde L. 
Published: April 2011

AbstractSortases are a class of bacterial enzymes that possess transpeptidase activity. It is their ability to site‐specifically break a peptide bond and then reform a new bond with an incoming nucleophile that makes sortase an attractive tool for protein engineering. This technique has been adopted for a range of applications, from chemistry‐based to cell biology and technology. In this Minireview we provide a brief overview of the biology of sortase enzymes and current applications in protein engineering. We identify areas that lend themselves to further innovation and that suggest new applications.
Imidazole‐coordinated monodentate NHC–Pd(II) complex derived from proline and its application to the coupling reaction of arylboronic acids with carboxylic acid anhydrides in water at room temperature
Authors: Shen Xiao‐Bao , Gao Ting‐Ting , Lu Jian‐Mei , Shao Li‐Xiong 
Published: April 2011

AbstractCleavage of a CN bond of imidazolium salt derived from N‐phenyl‐substituted proline was observed in this laboratory. A novel imidazole‐coordinated monodentate NHC–Pd(II) complex 5 was obtained as the sole product in good yield in the reaction of imidazolium salt 4 with Pd(OAc)2 in refluxing THF. The structure of complex 5 was determined unambiguously by an X‐ray diffraction. The complex was found to be a good catalyst in the cross‐coupling reaction of arylboronic acids with carboxylic acid anhydrides in water at room temperature. Copyright © 2011 John Wiley & Sons, Ltd.
Modeling analysis of chain transfer in reversible addition‐fragmentation chain transfer polymerization
Authors: Gao Xiang , Zhu Shiping 
Published: April 2011

AbstractThe validity of simplifying the reversible addition‐fragmentation chain transfer (RAFT) polymerization as a degenerative chain transfer process was verified in this work. The simplified chain transfer mechanism enabled the direct modeling investigation of chain transfer coefficient in the RAFT polymerization. It also gave the analytical expressions for concentration, chain length, and polydispersity of various chain species. The comparison between the simulations based on chain transfer mechanism and those from general RAFT mechanism showed that this simplified mechanism can accurately predict RAFT polymerization in the absence of side reactions to adduct radicals other than fragmentation. However, significant errors are introduced at high conversion when side reactions to adduct are present. The chain transfer coefficient of RAFT agent is the key factor in RAFT polymerization. The polydispersity is more sensitive to chain transfer coefficient at low conversion. At high conversion, however, the polydispersity is mainly determined by termination, which can be controlled by RAFT agent concentration and the selection of initiator. At last, an analytical equation is derived to directly estimate chain transfer coefficient of RAFT agent from the experimental data. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Modeling evidence in support of coagulative nucleation theory
Authors: Sood Ashwini , Lodhi Pankaj Kumar 
Published: April 2011

AbstractAn extensive lumped model was developed for emulsion polymerization. It incorporated all of the complex processes: aqueous‐phase radical balances for all radical species arising from initiator decomposition and from exit; determination of radical number inside the particles by balance among rates of radical entry into, exit from, and termination inside the particles; determination of the monomer concentration inside the particles and in the aqueous phase by a thermodynamic equation; and particle formation by micellar, homogeneous, and coagulative nucleation. Model validation was done for the system with styrene (monomer), potassium persulfate (initiator), and sodium dodeceyl sulfate (emulsifier) and for the variables, which included the duration of nucleation, conversion at the end of nucleation, and total number of particles formed. The validation process revealed that coagulation during nucleation needed to be included in the model, even for emulsifier concentrations above the critical micelle concentration. The model predictions were in good quantitative agreement with the experimental data. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Graft copolymerization of methyl methacrylate onto cellulosic biofibers
Authors: Thakur Vijay Kumar , Singha Amar Singh , Misra Bhupendra Nath 
Published: April 2011

AbstractIn this article, we have used the potassium persulfate to initiate the graft copolymerization of methyl methacrylate onto cellulosic biofibers in aqueous medium. Different reaction parameters, such as reaction time, initiator molar ratio, monomer concentration, amount of solvent, and reaction temperature, were optimized to get the maximum percentage of grafting (50.93%). The graft copolymers thus formed were characterized by Fourier transform infrared, scanning electron microscopy, X‐ray diffraction, and thermogravimetric, differential thermal analysis, and derivative thermogravimetric techniques. A mechanism is proposed to explain the generation of radicals and the initiation of graft copolymerization reactions. On grafting, percentage crystallinity decreases with reduction in its stiffness and hardness. The effect of grafting percentage on the physicochemical properties of raw as well as grafted fibers has also been investigated. The graft copolymers have been found to be more moisture resistant and also showed better chemical and thermal resistance. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Crystallization behavior of polyamide 11/multiwalled carbon nanotube composites
Authors: Yang Zhe , Huang Shu , Liu Tianxi 
Published: April 2011

AbstractDifferential scanning calorimetry (DSC) was used to investigate the isothermal and nonisothermal crystallization kinetics of polyamide11 (PA11)/multiwalled carbon nanotube (MWNTs) composites. The Avrami equation was used for describing the isothermal crystallization behavior of neat PA11 and its nanocomposites. For nonisothermal studies, the Avrami model, the Ozawa model, and the method combining the Avrami and Ozawa theories were employed. It was found that the Avrami exponent n decreased with the addition of MWNTs during the isothermal crystallization, indicating that the MWNTs accelerated the crystallization process as nucleating agent. The kinetic analysis of nonisothermal crystallization process showed that the presence of carbon nanotubes hindered the mobility of polymer chain segments and dominated the nonisothermal crystallization process. The MWNTs played two competing roles on the crystallization of PA11 nanocomposites: on the one hand, the MWNTs serve as heterogeneous nucleating agent promoting the crystallization process of PA11; on the other hand, the MWNTs hinder the mobility of the polymer chains thus retarding the crystal growth process of PA11. The activation energies of PA11/MWNTs composites for the isothermal and nonisothermal crystallization are lower than neat PA11. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Modeling the delamination process during shear premixing of nanoclay/thermoset polymer nanocomposites
Authors: Ngo T.‐D. , Wood‐Adams P. M. , Hoa S. V. , Ton‐That M.‐T. 
Published: April 2011

AbstractAs shear premixing is an important process for the dispersion of nanoclays in polymeric resins, this article studies the effect of temperature, duration, speed of premixing, and also the interlamellar spacing of clay platelets on the dispersion of organoclay in epoxy by using a high speed premixing technique which can generate high shear. The quality of dispersion and intercalation/exfoliation of organoclay in epoxy after premixing (before adding hardener) was analyzed by means of X‐ray diffraction (XRD) and rheological measurement. The dispersion and intercalation/exfoliation of organoclay in the epoxy nanocomposites (ENCs) after curing were characterized by TEM. The results illustrate that the intercalation/exfoliation of organoclay in epoxy at the premixing step is very much depending on the premixing parameters. This article also presents a model which takes into account the parameters such as the interlamellar spacing of clay platelets, the viscosity of the epoxy‐clay mixtures, and the velocity of the mixer to explain their effect on the dispersion of clay in epoxy resin. The study focuses on the flow of epoxy clay in the high shear mixer to describe a model for predicting the processing conditions necessary for achieving delamination of the clay layers. Experimental results on the dispersion of clay are also provided to validate the model. The model provides a guide for the premixing parameters necessary to separate the clay layers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Oxidative degradations of oxodegradable LDPE enhanced with thermoplastic pea starch: Thermo‐mechanical properties, morphology, and UV‐ageing studies
Authors: Raquez Jean‐Marie , Bourgeois Audrey , Jacobs Heidi , Degée Philippe , Alexandre Michael , Dubois Philippe 
Published: April 2011

AbstractThe abiotic UV‐degradation behavior of oxodegradable LDPE was investigated in the presence of thermoplastic pea starch (TPPS) in this study. Oxodegradable LDPE was first melt‐blended with thermoplastic pea starch (TPPS) using an internal mixing chamber to enhance the abiotic oxidative degradation of oxodegradable LDPE. Because of their different affinity, maleated polyethylene was added as compatibilizer. Tensile properties, thermal properties, and morphology of resulting melt‐blends were determined at different content in TPPS. High content in TPPS (40 wt %) could be readily added to oxodegradable LDPE without affecting the tensile properties of resulting melt‐blends. UV‐ageing studies on compatibilized TPPS/oxodegradable LDPE melt‐blends were carried out by Attenuated Total Reflectance infrared spectroscopy (ATR‐FTIR), Dynamic Thermomechanical Analyses (DMTA) and Differential Scanning Calorimetry (DSC) under abiotic conditions. These results suggested a synergistic effect on the UV‐ageing of TPPS‐based melt‐blends provided by both components during the first stage of UV‐irradiation. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.
Broken barriers: Human‐induced changes to gene flow and introgression in animals
Authors: Crispo Erika , Moore Jean‐Sébastien , Lee‐Yaw Julie A. , Gray Suzanne M. , Haller Benjamin C. 
Published: April 2011

AbstractWe identify two processes by which humans increase genetic exchange among groups of individuals: by affecting the distribution of groups and dispersal patterns across a landscape, and by affecting interbreeding among sympatric or parapatric groups. Each of these processes might then have two different effects on biodiversity: changes in the number of taxa through merging or splitting of groups, and the extinction/extirpation of taxa through effects on fitness. We review the various ways in which humans are affecting genetic exchange, and highlight the difficulties in predicting the impacts on biodiversity. Gene flow and hybridization are crucially important evolutionary forces influencing biodiversity. Humans alter natural patterns of genetic exchange in myriad ways, and these anthropogenic effects are likely to influence the genetic integrity of populations and species. We argue that taking a gene‐centric view towards conservation will help resolve issues pertaining to conservation and management.Editor's suggested further reading in BioEssays A systemic view of biodiversity and its conservation: Processes, interrelationships, and human culture Abstract
Impact of single-port cholecystectomy on postoperative pain
Authors: Asakuma M , Hayashi M , Komeda K , Shimizu T , Hirokawa F , Miyamoto Y , Okuda J , Tanigawa N 
Published: April 2011

Abstract

Background
This study compared postoperative pain following four-port laparoscopic cholecystectomy (LC) and single-port cholecystectomy (SPC).

Method
This prospective, quasi-randomized, single-centre trial focusing on postoperative pain included 49 patients undergoing elective surgery with either a conventional LC, or SPC using a surgical glove port. Postoperative pain was evaluated using a visual analogue scale (VAS) and postoperative analgesic use as primary outcome measures. Total duration of operation, length of hospital stay, blood test results on the day after surgery and total port cost were secondary outcome measures.

Results
Twenty-five LCs and 24 SPCs were undertaken. The VAS score on day 1 after surgery was significantly less in the SPC group than in the LC group: median (range) 24 (12–38) versus 45 (33–57) mm (P = 0·002). Significantly fewer patients in the SPC group required analgesia (9 of 24 versus 19 of 25 in the LC group; P = 0·007). There were no significant differences in total duration of operation, length of hospital stay, and blood test results on the day after surgery.

Conclusion
Single-port surgery using a surgical glove port reduces postoperative pain compared with conventional LC. Registration number: UMIN000002539 (http://www.umin.ac.jp/ctr/index.htm).
Environmental Policies and Firm Value
Authors: Al‐Najjar Basil , Anfimiadou Aspioni 
Published: April 2011

ABSTRACTMany organizations are currently becoming more environmentally friendly. Eco‐efficiency maximizes the effectiveness of a business operation while reducing its impact on the environment; with the necessary skills, organizations can create more value while using less input. Prior empirical studies have suggested that firms engaging in eco‐efficient activities are better valued than those without such activities. Therefore, this will enhance business efficiency and excellence. This study investigates the link between eco‐efficiency, as environmental policy, and firm value in the United Kingdom (UK) for the period 1999 to 2008. We generate new insights into environmental–financial performance by using different definitions of the term ‘eco‐efficiency’. In the UK context our results support that eco‐efficient firms have higher market values than those lacking environmental strategies. Hence, we recommend that firms become involved in environmental polices since the adoption of these polices will have a positive impact on firm value. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment.
Integrating Suppliers into Green Product Innovation Development: an Empirical Case Study in the Semiconductor Industry
Authors: Lee Ki‐Hoon , Kim Ji‐Whan 
Published: April 2011

ABSTRACTGreen innovation has been recognized as one of the key factors to achieve environmental and economic success in markets. Understanding green product innovation development as a result of suppliers' involvement has become a strategic priority for academics and practitioners. This paper aims to explore and understand the role of suppliers in enhancing the manufacturer's ability to successfully carry out green innovation in product development. As a research methodology, a case study approach is employed. Primary data were collected through site visits and extensive interviews with corporate and plant management in Korea. Based on the Korean study, the paper presents following outcomes. First, there is a strong linkage between environmental compliance and green new product developments. Second, there is a strategically close relationship of environmental collaboration between suppliers and the buying company through technological integration. Finally, involving key suppliers in green new product development for environmentally demanding customers and markets can bring both environmental and commercial success. This research provides new insights on supplier involvement and green product innovation development in supply chain management. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment.
Morphogenesis of the human palma arch using three‐dimensional geometric modeling
Authors: Durand Sebastien , Marin Frederic , Oberlin Christophe , Ho Ba Tho Marie‐Christine 
Published: April 2011

AbstractThe hand goes through complex morphological modifications during embryogenesis. The goal of this study was to use geometric modeling to study the morphometric modifications of the palmar arch. Five embryos were used for the study (sizes: 15, 17, 23, 30, and 44 mm). After digitalization of histologic sections (Sony DXC‐930P 3CCD camera, Leica Qwin) and segmentation of the metacarpal cartilaginous matrices (Winsurf 4.3 software), geometric modeling and calculations were performed using MSC.Patran 2005r2 software. Correlations (r > 0.99) were found between embryo size and metacarpal volume, metacarpal surface, and the surface of the modeled palmar arch. The growth of the palmar arch is nonhomothetic. Significant reduction (P = 0.05) in the divergence of the 2nd, 3rd, 4th, and 5th metacarpals was observed. Deepening of the palmar arch is correlated with embryo size and age (r > 0.99). Geometric modeling allows 3D rendering of histologic sections and thus quantitative description of the morphogenesis. The results of this study support the hypothesis that opposition of the thumb in correlation with deepening of the palmar arch appears early in embryological development. It constitutes a specific morphological characteristic that appears very early in the human phylum. The fact that the human thumb is naturally in opposition in the resting position is a consequence of this morphogenesis. The thumb's resting position has received little attention in clinical settings and should be considered as the reference position for biomechanical analysis of the thumb column. Clin. Anat. 24:874–879, 2011. © 2011 Wiley‐Liss, Inc.
Synostosis of the joint between the body and greater cornu of the human hyoid bone
Authors: Kanetaka Hiroyasu , Shimizu Yoshinaka , Kano Mitsuhiro , Kikuchi Masayoshi 
Published: April 2011

AbstractThe structure of the joint between the body and the greater cornu in the human hyoid bone was examined histologically in 259 cadavers (16–98 years). Joints were classified into three grades based on histological observations. Grade I showed fibrocartilage without degenerative change in the marginal region of the joint. Grade II showed prominent calcification or ossification on the outer margin of the joint without fusion. Grade III showed bony fusion. Histological changes with age were revealed by a comparison of the prevalences of these three grades among individuals of three age groups: young adult (16–39 years), middle aged (40–69 years), and elderly (70+ years). The frequency of hyoid bones with diarthrodial structure of this joint was compared between the age groups. The mean age of subjects with each grade of histological changes was calculated. Results show that, with age, the proportion of Grade I decreased significantly (P < 0.05) and that of Grade III increased significantly. Joints with diarthrodial structure decreased significantly with age relative to all subjects (P < 0.05). Clefts with necrotic tissue were observed in cartilage along with progressive calcification. The mean age of subjects with the histological changes was significantly higher than that of individuals without such changes (P < 0.05). Calcification and ossification of joints were induced with age from fibrous tissue and cartilage on the outer margin of a joint. The authors suggest that the age changes in the joint between the body and greater cornu of the hyoid bone may affect the mobility of this joint and may be related to masticatory and swallowing functions. Clin. Anat. 24:837–842, 2011. © 2011 Wiley‐Liss, Inc.
Swelling around a child's knee
Authors: Osman Mohamed K. , Irwin Greg J. , Huntley James S. 
Published: April 2011

AbstractSwellings around the paediatric knee have a large differential diagnosis, although the majority can be diagnosed clinically. Some swellings merit further investigation by Magnetic Resonance Imaging (MRI). Clin. Anat. 24:914–917, 2011. © 2011 Wiley‐Liss, Inc.