bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vascularized periosteal graft from the first metatarsal bone: A new technique to prevent collapse of osteonecrosis of the talus in children. A case report
Authors: Soldado Francisco , Barrera‐Ochoa Sergi , Fontecha Cesar Garcia , Haddad Sleiman , Barastegui David , Barber Ignasi , Rego Paulo 
Published: September 2012

AbstractSeveral microsurgical techniques have been described for the treatment of osteonecrosis of the talus (ONT). Recently reported in children, vascularized periosteal grafts showed promising revascularizing properties. We report a novel technique using a pedicled periosteal graft from the first metatarsal bone to treat steroid‐induced early Ficat‐Arlet stage III ONT in an 11‐year‐old boy. The patient presented initial favorable clinical and radiological results which were maintained at 34 months during the last follow‐up. Through this original technique, and basing on the powerful osteogenic and vasculogenic propreties of periosteal flaps, we could effectively induce bone revascularization and prevent further collapse of the talar dome. © 2012 Wiley Periodicals, Inc. Microsurgery, 2013
CNP/NPR2 signaling maintains oocyte meiotic arrest in early antral follicles and is suppressed by EGFR‐mediated signaling in preovulatory follicles
Authors: Tsuji Takehito , Kiyosu Chiyo , Akiyama Kouyou , Kunieda Tetsuo 
Published: September 2012

AbstractOocyte meiosis is arrested at prophase I by factors secreted from surrounding somatic cells after oocytes acquire meiotic competence at an early antral stage, and meiosis resumes in preovulatory follicles as a result of the luteinizing hormone (LH) surge. Recently, signaling by C‐type natriuretic peptide (CNP) through its receptor, natriuretic peptide receptor 2 (NPR2), was found to be essential for meiotic arrest at the late antral stage. Whether or not CNP/NPR2 signaling maintains oocyte meiotic arrest in earlier follicular stages and how it is associated with meiotic resumption induced by the LH surge is unclear. In this study, we examined the expression of Nppc and Npr2, respectively encoding CNP and NPR2, in the ovaries of immature mice. Nppc and Npr2 mRNA were specifically expressed in the outer and inner granulosa cell layers, respectively, in early antral follicles. Histological analysis of mice with a mutation in Npr2 revealed precocious resumption of oocyte meiosis in early antral follicles. Ovaries of mice treated with excess human chorionic gonadotropin (hCG) exhibited markedly decreased Nppc mRNA levels in granulosa cells of preovulatory follicles. Moreover, we found that amphiregulin, a mediator of LH/hCG activity through epidermal growth factor receptor (EGFR), suppressed Nppc mRNA levels in cultured granulosa cells. These results suggest that CNP/NPR2 signaling is essential for oocyte meiotic arrest in early antral follicles and that activated LH/amphiregulin/EGFR signaling pathway suppresses this signal by downregulating Nppc expression. Mol. Reprod. Dev. 79: 795–802, 2012. © 2012 Wiley Periodicals, Inc.
Family Medicine: A Specialty for All Ages
Authors: Calman Neil S. , Hauser Diane , Leanza Francesco , Schiller Robert 
Published: September 2012

AbstractAfter a diminishing of its ranks following the post–World War II explosion of growth in medical discoveries, advanced medical technology, and the concomitant specialization of the physician workforce, family medicine is re‐establishing itself as a leading medical specialty that has garnered growing interest among recent medical‐school graduates. Family physicians provide care for patients of all ages, from newborns to the elderly. In addition to its wide scope of practice, family medicine is characterized by its emphasis on understanding of the whole person, its partnership approach with patients over many years, and its command of medical complexity. Family physicians are trained both to use community resources to assist individual patients in meeting medical or social needs and to identify and address community‐wide needs. The specialty of family medicine is uniquely positioned to provide a leadership role in health‐reform efforts that are accelerating across the country. Health care models that are gaining traction, such as the patient‐centered medical home model, health homes, and accountable care organizations, share the characteristics of providing comprehensive, coordinated patient care with an emphasis on disease prevention and health promotion. This model of care, provided in the context of family and community, has been the hallmark of family medicine since its creation as a distinct medical specialty more than 40 years ago. In addition, family physicians' ability to care for patients of all ages make them particularly cost‐effective as the new models of care move to improve access to care through expanded hours and locations. Mt Sinai J Med 79:603–609, 2012. © 2012 Mount Sinai School of Medicine
Bone Degradation and Environment: Understanding, Assessing and Conducting Archaeological Experiments Using Modern Animal Bones
Authors: Karr L. P. , Outram A. K. 
Published: September 2012

AbstractArchaeological experiments that use modern bones to replicate past animal bone assemblages have often failed to consider the effects of environment, storage and preparation on modern bones. Often, these experiments make little mention of the conditions to which bones were subject during their storage and preparation for use in experiments. In other instances, these variables are reported but not considered as factors that contribute to the nature of the results obtained. This study considers previously reported data concerning the degradation of frozen bones (−20°C), and bones exposed to hot, dry conditions (40°C), and presents new data for bones exposed to room temperature environments (22°C) and refrigerated environments (2°C), and bones that are frozen (−20°C) and then thawed (22°C). These conditions are all relevant to understanding the nature of bone degradation and the use of bones in modern archaeological experimentation. This article also surveys a range of previously reported experiments that utilise modern bones to create analogies to the past and considers different methodological approaches and their relationship to the condition of bones at the time of their fracture and fragmentation. The longitudinal data presented in this study demonstrate differential rates of bone degradation over time in various environmental conditions. This degradation results in dramatic changes in bone fracture morphology, bone strength and utility for bone tool production. These observations have significant implications for experiments that utilise modern bones, especially when experimental data are used to create analogies to the archaeological past. Copyright © 2012 John Wiley & Sons, Ltd.
HPLC–ESI–QTOF–MS as a Powerful Analytical Tool for Characterising Phenolic Compounds in Olive‐leaf Extracts
Authors: Quirantes‐Piné Rosa , Lozano‐Sánchez Jesús , Herrero Miguel , Ibáñez Elena , Segura‐Carretero Antonio , Fernández‐Gutiérrez Alberto 
Published: September 2012

ABSTRACTIntroductionOlea europaea L. leaves may be considered a cheap, easily available natural source of phenolic compounds. In a previous study we evaluated the possibility of obtaining bioactive phenolic compounds from olive leaves by pressurised liquid extraction (PLE) for their use as natural anti‐oxidants. The alimentary use of these kinds of extract makes comprehensive knowledge of their composition essential.ObjectiveTo undertake a comprehensive characterisation of two olive‐leaf extracts obtained by PLE using high‐performance liquid chromatography coupled to electrospray ionisation and quadrupole time‐of‐flight mass spectrometry (HPLC–ESI–QTOF–MS).MethodOlive leaves were extracted by PLE using ethanol and water as extraction solvents at 150°C and 200°C respectively. Separation was carried out in a HPLC system equipped with a C18‐column working in a gradient elution programme coupled to ESI–QTOF–MS operating in negative ion mode.ResultsThis analytical platform was able to detect 48 compounds and tentatively identify 31 different phenolic compounds in these extracts, including secoiridoids, simple phenols, flavonoids, cinnamic‐acid derivatives and benzoic acids. Lucidumoside C was also identified for the first time in olive leaves.ConclusionThe coupling of HPLC–ESI–QTOF–MS led to the in‐depth characterisation of the olive‐leaf extracts on the basis of mass accuracy, true isotopic pattern and tandem mass spectrometry (MS/MS) spectra. We may conclude therefore that this analytical tool is very valuable in the study of phenolic compounds in plant matrices. Copyright © 2012 John Wiley & Sons, Ltd.
Dielectric properties of copolymers based on cyano monomers and methyl α‐acetoxyacrylate
Authors: Raihane Mustapha , Zerroukhi Amar , Kaddami Hamid , Lahcini Mohammed , Boiteux Gisèle 
Published: September 2012

AbstractWith the aim of developing dielectric polymers containing CN groups with strong dipole moment, alternating and statistical copolymers of the cyano monomers vinylidene cyanide (VCN), acrylonitrile and methacrylonitrile with methyl α‐acetoxyacrylate (MAA) were synthesized and characterized. The copolymer's composition and microstructure were analysed by NMR spectroscopy, SEC and elemental analysis. The reactivity ratios calculated from the Q–e Alfrey–Price parameters for these copolymers indicated the alternating and statistical structures confirmed by NMR analysis. The copolymers have glass transition temperatures Tg in the range 83–146 °C and are stable up to 230 °C. The thermal stability of the copolymers depends on the nature of the cyano monomers. Their molecular dynamics were investigated by dielectric relaxation spectroscopy. We revealed a weak relaxation β at sub‐Tg temperature for poly(VCN‐co‐MAA) usually originating from molecular motions that are restricted to the scale of a few bond lengths. Strong α‐relaxation processes occurred above Tg for these copolymers. This primary relaxation was associated with cooperative movements of the polar groups (CN) at the time of mobility of the principal chains. The activation energy of the α‐relaxation process was also calculated. The values of the dielectric increment Δε for these copolymers were determined by Cole–Cole plots and indicated that the copolymers exhibit interesting dielectric properties compared with similar cyano materials. The polarity–permittivity relationship was also established. © 2012 Society of Chemical Industry
AB, BAB and (AB)3 poly(ε‐caprolactone)‐based block copolymers with functionalized poly(meth)acrylate segments
Authors: Neugebauer Dorota , Bury Katarzyna , Maksym‐Bȩbenek Paulina , Biela Tadeusz 
Published: September 2012

AbstractLinear and star‐shaped poly(ε‐caprolactone) (PCL) block copolymers containing poly(meth)acrylate segments with glycidyl, 2‐(trimethylsilyloxy)ethyl and tert‐butyl pendant groups were synthesized using mono‐, di‐ and trifunctional PCL macroinitiators and appropriate (meth)acrylate monomers by controlled radical polymerization. The well‐defined structures with narrow molecular weight distributions indicate the coexistence of semi‐crystalline PCL and amorphous poly(meth)acrylic phases. The hydrophobic nature of the block copolymers can be easily converted to amphiphilic, which with biodegradable and biocompatible PCL segments are promising as polymeric carriers in drug delivery systems. © 2012 Society of Chemical Industry
Organometallic synthesis of n‐type π‐conjugated polymers with dopant cation trapping sites and stability of n‐doping state against air
Authors: Yamaguchi Isao , Uehara Ryohei 
Published: September 2012

Abstractn‐Type π‐conjugated polymers comprising a 1,2,4‐triazole ring substituted by a benzo‐15‐crown 5‐ether (benzo15C5) subunit at the 4‐position of the 1,2,4‐triazole ring and n‐type aromatic rings such as pyridine‐2,5‐diyl and 2,1,3‐benzothiadiazole‐4,7‐diyl rings were synthesized by organometallic polycondensation. The UV‐visible spectra of the polymers exhibited absorption maxima (λmax values) at a longer wavelength than that exhibited by 3,5‐bis(2‐bromopyridyl)‐4‐benzo15C5‐1,2,4‐triazole, revealing that their π‐conjugation system was expanded along the polymer chain. The polymers with the benzo15C5 subunit underwent an electrochemical reduction (n‐doping), and the corresponding oxidation (n‐dedoping) occurred at an unusually high potential in an acetonitrile solution of NaClO4; the factor responsible for the unusually high oxidation potential was the stabilized n‐doping state that was attributed to the inclusion of Na+ in the 15C5 ring. The polymers with the benzo15C5 subunit exhibited a considerably higher stability of the n‐doping state in air than did those without this subunit. Copyright © 2012 Society of Chemical Industry
Polyaniline doped with α, ω‐alkanedisulfonic acids: preparation and characterization
Authors: Bharti Sneh , Jacob Josemon , Ghosh Anup K 
Published: September 2012

AbstractThe use of α, ω‐alkanedisulfonic acid, HO3S(CH2)nSO3H (n = 1, 4, 6 and 12), as a dopant for polyaniline (PANi) was investigated. This series of disulfonic acids with varying chain lengths were synthesized and used in the doping of PANi. The doped polymers showed conductivity in the range 10−2 to 10−1 S cm−1. Thermal studies showed that the doped polymers, depending on the chain length of α,ω‐alkanedisulfonic acid, were stable up to ca 300 °C and the thermal stability decreased with increasing dopant chain length. The thermal stability of α,ω‐alkanedisulfonic acid‐doped PANi was higher than that of alkanesulfonic acid‐doped PANi which typically degrades around 250 °C, suggesting a moderately broader processing window for α,ω‐alkanedisulfonic acid‐doped PANi for blending with other thermoplastics. Copyright © 2012 Society of Chemical Industry
Porphyrin–diindenothieno[2,3‐b]thiophene alternating copolymer—a blue‐light harvester in ternary‐blend polymer solar cells
Authors: Wu Yu‐Chun , Chao Yi‐Hsiang , Wang Chien‐Lung , Wu Chun‐Ta , Hsu Chain‐Shu , Zeng Yu‐Ling , Lin Ching‐Yao 
Published: September 2012

AbstractPorphyrin, despite chosen by Nature as light harvesting units, hasn't revealed its full potentials as a structural unit in porphyrin‐incorporated polymers (PPors). A novel PPor was synthesized to investigate the origins of the low performances of PPor‐based polymer solar cells (PSCs). The polymer features broad absorption in the blue‐light region, because the diindenothieno[2,3‐b]thiophene (DITT) unit extended the conjugation in the polymer backbone. PPor‐DITT/PC71BM based PSCs have a high Voc (0.79 V). Their low Jsc and fill factor (FF) were attributed to the un‐optimized morphology, as indicated by the photoluminescence quenching and atomic force microscopy (AFM) experiments. Using PPor‐DITT as a blue‐light harvesting dopant in an amorphous host leverage the strong 400–550 nm absorption of PPor‐DITT and circumvent the difficulties in reaching optimized morphology in the PPor/PCBM thin films. An addition of 2 wt % of PPor‐DITT in ternary‐blend PSCs resulted in a 10 % increase of external quantum efficiency (EQE) in the blue‐light region. However, in a crystalline host, the dopant decreased the crystallinity of the host and led to large drops in FF and power conversion efficiencies (PCEs). The study provides an alternative route and expands the application of PPors in PSCs as a blue‐light harvester in ternary‐blend PSCs using amorphous polymers as host. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Preparation and properties of novel low dielectric constant benzoxazole‐based polybenzoxazine
Authors: Zhang Kan , Zhuang Qixin , Zhou Yunchao , Liu Xiaoyun , Yang Guang , Han Zhewen 
Published: September 2012

AbstractA novel benzoxazine monomer containing a benzoxazole group was synthesized using a nonsolvent method and then named DAROH‐a. The structure of DAROH‐a was confirmed by FTIR, 1H NMR, elemental analysis, and mass spectrometry. The curing reaction activation energy was calculated at 140 kJ/mol. Its corresponding crosslinked polybenzoxazines, poly(DAROH‐a), displayed a higher glass transition temperature at 402 °C, a 9% weight loss at the said temperature, and a high char yield of 42 wt % (800 °C, in nitrogen). Moreover, the dielectric constants of poly(DAROH‐a) were low and changed only slightly at different temperatures. Furthermore, the dielectric constants and dielectric loss of poly(DAROH‐a) at the same frequency barely changed from room temperature to 150 °C. The photophysical properties of poly(DAROH‐a) film were also investigated. Poly(DAROH‐a) showed an absorption peak at 280 nm. The photoluminescent emission spectrum of poly(DAROH‐a) film displayed predominant emission peaks at 521 nm. It might have potential application as high‐performance materials because of its excellent dielectric constants stability and thermal stability under high temperature. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Psychological morbidity, burden, and the mediating effect of social support in adult children caregivers of oncological patients undergoing chemotherapy
Authors: Teixeira Ricardo J. , Pereira Maria Graça 
Published: September 2012

AbstractObjectivesThis study examines the association between psychological morbidity, social support, and demographic and clinical variables in adult children of cancer patients undergoing chemotherapy. Special attention was given to the variable level of parental dependency. The main predictors of caregiving burden were tested, as well as the mediating role of social support in the relationship between psychological morbidity and burden.MethodsA total of 214 adult children caregivers of parents with cancer were recruited in Northern Portugal central hospitals. Caregivers completed Portuguese versions of the Depression Anxiety and Stress Scales, Impact of Event Scale—Revised, Satisfaction with Social Support Scale, and Burden Assessment Scale.ResultsSignificant associations among psychological, demographic, and clinical variables were found. Adult children with a greater perception of parent's dependency showed more distress, higher posttraumatic stress disorder (PTSD) symptoms, greater caregiving burden, and less satisfaction with social support. Hierarchical regression analyses revealed the main predictors of caregiver burden to be as follows: being a woman, caregiving duration, having a dependent parent, more distress and PTSD symptoms, and poorer social support. Social support was found to be a partial mediator in the relationship between psychological morbidity and caregiver burden.ConclusionsResults underscore the importance of perceived parental dependency in offspring's caregivers. Findings support the multidimensional issues associated to burden in this specific population, stressing satisfaction with social support as an important mediator between distress/PTSD and burden. Implications for further research as well as limitations of the present study are discussed. Psychosocial interventions should focus on caregivers' social resources to facilitate psychological well‐being. Copyright © 2012 John Wiley & Sons, Ltd.
Track by Track: The Structure of Single Tracks of Atmospheric Pressure Plasma Polymerized Hexamethyl Disiloxane (HMDSO) Analyzed by Infrared Microscopy
Authors: Merten Christian , Regula Christoph , Hartwig Andreas , Ihde Jörg , Wilken Ralph 
Published: September 2012

AbstractA comprehensive infrared microscopic study of single tracks of atmospheric pressure plasma polymerised HMDSO is presented. The effects of different process parameters, i.e. the process gas, the nozzle setting (distance between discharge chamber and injection point of the monomer gas), and the nozzle speed, are investigated. It is shown that the chemical structure of singles tracks is not homogenous along the deposit. An increase of the oxygen content in the process gas or an increase of the excitation energy transferred to the monomer gas increase the relative content of SiOCH3 and SiOH units within the bulk polymer network. The deposition of superposed tracks is studied as well and it is revealed that the structure of the coating is changed compared to the first track. magnified image
Gettering effect in grain boundaries of multi‐crystalline silicon
Authors: Nouri H. , Bouaïcha M. , Ben Rabha M. , Bessaïs B. 
Published: September 2012

AbstractIn this work, we analyze the effect of three gettering procedures on the variation of the grain boundaries (GBs) defect density in multicrystalline silicon (mc‐Si). The effective defect density (NB) was calculated using a theoretical model where we consider the potential barrier induced by the GB as being due to structural defects and impurities. Results are compared to those obtained from C‐V measurements. The potential barrier was evaluated from the dark current‐voltage (I‐V) characteristic performed across the GB. In addition to the Rapid Thermal Annealing (RTA), we use aluminum (Al) in the first gettering procedure, in the second we use porous silicon (PS), whereas in the third one, we realize a chemical damage (grooving). Mc‐Si wafers were annealed in an infrared furnace in the same conditions, at temperatures ranging from 600 °C to 1000 °C (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phosphorous diffusion through silicon nitride thin film for selective emitter application
Authors: Crampette Laurent , Poulain Gilles , Cuminal Yvan , Foucaran Alain , Pellegrin Yvon , Semmache Bachir 
Published: September 2012

AbstractIn this paper, we present a concept of selective emitter silicon solar cells fabrication. The most common ways for selective emitter formation are using the laser processing after the phosphorous thermal diffusion step. In this work, we propose to start with PECVD deposition of a thin silicon nitride (SiNx) layer before performing the phosphorous diffusion process. The purpose is first to open the fingers area by laser ablation and then perform one diffusion step both through the SiNx barrier layer and directly on the ablated pattern. This ablated pattern is dedicated to the subsequent front metallic contacts. This way, selective emitter structures with various sheet resistance couples (Low, High) could be obtained. The high sheet resistance corresponds to the SiNx covered area and the low one is displayed on the ablated area. The phosphorous diffusion process through the SiNx barrier layer was controlled by emitter sheet resistance and QSSP lifetime measurements (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)