bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gpr177, a novel locus for bone mineral density and osteoporosis, regulates osteogenesis and chondrogenesis in skeletal development
Authors: Maruyama Takamitsu , Jiang Ming , Hsu Wei 
Published: November 2012

Abstract
Human genetic analysis has recently identified Gpr177 as a susceptibility locus for bone mineral density and osteoporosis. Determining the unknown function of this gene is therefore extremely important to furthering our knowledge base of skeletal development and disease. The protein encoded by Gpr177 exhibits an ability to modulate the trafficking of Wnt, similar to the Drosophila Wls/Evi/Srt. Because it plays a critical role in Wnt regulation, Gpr177 might be required for several key steps of skeletogenesis. To overcome the early lethality associated with the inactivation of Gpr177 in mice, conditional gene deletion is used to assess its functionality. Here we report the generation of four different mouse models with Gpr177 deficiency in various skeletogenic cell types. The loss of Gpr177 severely impairs development of the craniofacial and body skeletons, demonstrating its requirement for intramembranous and endochondral ossifications, respectively. Defects in the expansion of skeletal precursors and their differentiation into osteoblasts and chondrocytes suggest that Wnt production and signaling mediated by Gpr177 cannot be substituted. Because the Gpr177 ablation impairs Wnt secretion, we therefore identify the sources of Wnt proteins essential for osteogenesis and chondrogenesis. The intercross of Wnt signaling between distinct cell types is carefully orchestrated and necessary for skeletogenesis. Our findings lead to a proposed mechanism by which Gpr177 controls skeletal development through modulation of autocrine and paracrine Wnt signals in a lineage-specific fashion. © 2013 American Society for Bone and Mineral Research.
Characterization of malignancy of adnexal lesions using ADC entropy: Comparison with mean ADC and qualitative DWI assessment
Authors: Kierans Andrea S. , Bennett Genevieve L. , Mussi Thais C. , Babb James S. , Rusinek Henry , Melamed Jonathan , Rosenkrantz Andrew B. 
Published: November 2012

AbstractPurpose:To establish the utility of apparent diffusion coefficient (ADC) entropy in discrimination of benign and malignant adnexal lesions, using histopathology as the reference standard, via comparison of the diagnostic performance of ADC entropy with mean ADC and with visual assessments of adnexal lesions on conventional and diffusion‐weighted sequences.Materials and Methods:In all, 37 adult female patients with an ovarian mass that was resected between June 2006 and January 2011 were included. Volume‐of‐interest was drawn to incorporate all lesion voxels on every slice that included the mass on the ADC map, from which whole‐lesion mean ADC and ADC entropy were calculated. Two independent radiologists also rated each lesion as benign or malignant based on visual assessment of all sequences. The Mann–Whitney test and logistic regression for correlated data were used to compare performance of mean ADC, ADC entropy, and the visual assessments.Results:No statistically significant difference was observed in mean ADC between benign and malignant adnexal lesions (P = 0.768). ADC entropy was significantly higher in malignant than in benign lesions (P = 0.009). Accuracy was significantly greater for ADC entropy than for mean ADC (0.018). ADC entropy and visual assessment by the less‐experienced reader showed similar accuracy (P ≥ 0.204). The more experienced reader's accuracy was significantly greater than that of all other assessments (P ≤ 0.039).Conclusion:ADC entropy showed significantly greater accuracy than the more traditional metric of mean ADC for distinguishing benign and malignant adnexal lesions. Although whole‐lesion ADC entropy provides a straightforward and objective measurement, its potential benefit decreases with greater reader experience. J. Magn. Reson. Imaging 2013;37:164–171. © 2012 Wiley Periodicals, Inc.
Subtraction artifacts and frequency (Mis‐)alignment in J‐difference GABA editing
Authors: Evans C. John , Puts Nicolaas A.J. , Robson Siân E. , Boy Frederic , McGonigle David J. , Sumner Petroc , Singh Krish D. , Edden Richard A.E. 
Published: November 2012

PurposeTo compare the repeatability of γ‐aminobutyric acid (GABA) measurements using J‐difference editing, before and after spectral realignment—a technique which has previously been demonstrated to improve the quality of J‐difference GABA spectra.Materials and MethodsWe performed in vivo measurements in three brain regions (occipital, sensorimotor, and dorsolateral prefrontal cortex [DLPFC]), and analyzed these using alternative alignment approaches to evaluate the impact of alignment on repeatability: “Independent alignment” (aligning each subspectrum independently) and “Pairwise alignment” (aligning each on and off subspectrum as a pair) were compared.ResultsPairwise alignment improved the group mean coefficient of variation in all regions; 0.4% in occipital, 1.1% in sensorimotor, and 1.1% in DLPFC. Independent alignment resulted in subtraction artifacts in the majority of cases, and increased the coefficient of variation in the DLPFC by 9.4%. Simulations demonstrate that the GABA quantification error in datasets with high B0 drift, is 4.5% without alignment, but <1% with optimal alignment.ConclusionPairwise alignment improves the repeatability of GABA spectroscopy data. However, independently aligning all on and off subspectra can lead to artifacts and worse repeatability when compared with nonaligned data. J. Magn. Reson. Imaging 2013;38:970–975. © 2012 Wiley Periodicals, Inc.
Quantification of BOLD fMRI parameters to infer cerebrovascular reactivity of the middle cerebral artery
Authors: Mazzetto‐Betti Kelley C. , Leoni Renata F. , Pontes‐Neto Octavio M. , Sturzbecher Marcio J. , Santos Antonio C. , Leite Joao P. , Silva Afonso C. , de Araujo Draulio B. 
Published: November 2012

PurposeTo quantify the amplitude and temporal aspects of the blood oxygenation level‐dependent (BOLD) response to an auditory stimulus during normocapnia and hypercapnia in healthy subjects in order to establish which BOLD parameters are best suited to infer the cerebrovascular reactivity (CVR) in the middle cerebral artery (MCA) territory.Materials and MethodsTwenty healthy volunteers (mean age: 23.6 ± 3.7 years, 11 women) were subjected to a functional paradigm composed of five epochs of auditory stimulus (3 sec) intercalated by six intervals of rest (21 sec). Two levels of hypercapnia were achieved by a combination of air and CO2 while the end‐tidal CO2 (ETCO2) was continually measured. An autoregressive method was applied to analyze four parameters of the BOLD signal: onset‐time, time‐to‐peak, full‐width‐at‐half‐maximum (FWHM), and amplitude.ResultsBOLD onset time (P < 0.001) and full‐width at half‐maximum (FWHM) (P < 0.05) increased linearly, while BOLD amplitude decreased (P < 0.001) linearly with increasing levels of hypercapnia. Test–retest for reproducibility in five subjects revealed excellent concordance for onset time and amplitude.ConclusionThe robust linear dependence of BOLD onset time, FWHM, and amplitude to hypercapnia suggest future application of this protocol in clinical studies aimed at evaluating CVR of the MCA territory. J. Magn. Reson. Imaging 2013;38:1203–1209. © 2012 Wiley Periodicals, Inc.
Neuroprotective effects of umbelliferone and esculetin in a mouse model of Parkinson's disease
Authors: Subramaniam Sudhakar R. , Ellis Elizabeth M. 
Published: November 2012

AbstractThe production of reactive oxygen species and mitochondrial dysfunction in the brain are both associated with the progression of several neurodegenerative diseases, including Parkinson's disease. These characteristics are also observed when rodents are exposed to the neurotoxin 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP), a compound that causes nigrostriatal dopaminergic neurotoxicity and that has been used previously for assessing the effectiveness of neuroprotective agents. In this study, the neuroprotective effects of two coumarins, umbelliferone and esculetin, against MPTP‐induced neurotoxicity were examined in C57BL/6J mice. The results show that dietary administration of umbelliferone and esculetin significantly attenuated MPTP‐induced neurotoxicity in the substantia nigra pars compacta but not striatum, as measured by tyrosine hydroxylase staining. Both coumarins also prevented an MPTP‐induced increase in nitrosative stress as measured by 3‐nitrotyrosine immunoreactivity and also maintained glutathione levels in MPTP‐exposed mice as well as in cell lines exposed to the metabolite 1‐methyl‐4‐phenylpyridinium. Umbelliferone and esculetin also prevented MPTP‐dependent caspase 3 activation, an indicator of apoptosis, but did not inhibit monoamine oxidase activity. This is the first time that the neuroprotective capabilities of these coumarins have been demonstrated, and the results indicate that umbelliferone and esculetin can protect against MPTP‐induced neurotoxicity in the mouse. These compounds can cross the blood–brain barrier, so their effectiveness indicates that they have the potential to protect in neurodegenerative disease such as Parkinson's disease. © 2012 Wiley Periodicals, Inc.
Book review: A comparison of two books of microfinance pioneers
Authors: Ashta Arvind , Milana Carlo 
Published: November 2012

AbstractVikram Akula, A Fistful of Rice: My Unexpected Quest to End Poverty Through Profitability, Harvard Business School Publishing, Boston, MA, 2011, ISBN 978‐1‐4221‐3117‐6, Hardcover US$26.95, 191 pages.Muhamad Yunus, Banker to the Poor: Micro‐Lending and the Battle Against World Poverty, PublicAffairs, New York, 2007, ISBN‐13 978‐1‐58648/ISBN‐10 1‐58648‐198‐3, Paperback US$15.00, 288 pages.
Killian‐Jamieson diverticulum
Authors: Undavia Satyen , Anand Sumeet M. , Jacobson Adam S. 
Published: November 2012

AbstractKillian‐Jamieson diverticulum (KJD) is rare hypopharyngeal defect. As in other forms of esophageal diverticuli (i.e., Zenker's), recent literature has described minimally invasive endoscopic approaches to its management.1, 2 We present a case of a 62‐year‐old female with symptoms consistent with an esophageal diverticulum. A barium swallow study was consistent with a KJD. The patient was brought to the operating room and endoscopically examined to confirm the presence of this entity. A open transcervical approach was performed to remove the diverticulum without complication. During our dissection, the recurrent laryngeal nerve (RLN) was noted to be adherent to the base of the diverticulum and needed to be freed prior to performing the diverticulectomy. We provide a review of recent literature and medical illustrations to highlight the importance of the open transcervical approach in the management of KJD to avoid inadvertent transection of the RLN.
Facial nerve repair
Authors: Knox Christopher J. , Hohman Marc H. , Kleiss Ingrid J. , Weinberg Julie S. , Heaton James T. , Hadlock Tessa A. 
Published: November 2012

Objectives/HypothesisRepair of the transected facial nerve has traditionally been accomplished with microsurgical neurorrhaphy; however, fibrin adhesive coaptation (FAC) of peripheral nerves has become increasingly popular over the past decade. We compared functional recovery following suture neurorrhaphy to FAC in a rodent facial nerve model.Study DesignProspective, randomized animal study.MethodsSixteen rats underwent transection and repair of the facial nerve proximal to the pes anserinus. Eight animals underwent epineurial suture (ES) neurorrhaphy, and eight underwent repair with fibrin adhesive (FA). Surgical times were documented for all procedures. Whisking function was analyzed on a weekly basis for both groups across 15 weeks of recovery.ResultsRats experienced whisking recovery consistent in time course and degree with prior studies of rodent facial nerve transection and repair. There were no significant differences in whisking amplitude, velocity, or acceleration between suture and FA groups. However, the neurorrhaphy time with FA was 70% shorter than for ES (P < 0.05).ConclusionAlthough we found no difference in whisking recovery between suture and FA repair of the main trunk of the rat facial nerve, the significantly shorter operative time for FA repair makes this technique an attractive option. The relative advantages of both techniques are discussed.Level of EvidenceN/A
Two‐Grid method for nonlinear parabolic equations by expanded mixed finite element methods
Authors: Chen Yanping , Chen Luoping , Zhang Xiaochun 
Published: November 2012

AbstractIn this article, we develop a two‐grid algorithm for nonlinear reaction diffusion equation (with nonlinear compressibility coefficient) discretized by expanded mixed finite element method. The key point is to use two‐grid scheme to linearize the nonlinear term in the equations. The main procedure of the algorithm is solving a small‐scaled nonlinear equations on the coarse grid and dealing with a linearized system on the fine space using the Newton iteration with the coarse grid solution. Error estimation to the expanded mixed finite element solution is analyzed in detail. We also show that two‐grid solution achieves the same accuracy as long as the mesh sizes satisfy H = O(h1/2). Two numerical experiments are given to verify the effectiveness of the algorithm. © 2012 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2013
A cross‐cultural perspective on aging and memory: Comparisons between Bangladesh and Sweden
Authors: Sternäng Ola , Kabir Zarina N. , Hamadani Jena D. , Wahlin Åke 
Published: November 2012

AbstractMost studies on cognitive aging have been conducted in high‐income countries (mainly on Western populations). The main aim of this study was to compare the relative importance of predictors of episodic and semantic memory performance in older people (≥60 years) from Bangladesh (n = 400) and Sweden (n = 1,098). Hierarchical regression models were used in order to study the importance of some commonly used predictors in the two countries. A main finding was that variations in age did not have much impact on episodic and semantic memory performance in Bangladesh. Instead, sex was a strong predictor for semantic memory performance. In Sweden this pattern was reversed. In the Western world, chronological age is believed to be strongly associated with memory performance in cross‐sectional studies, particularly in people greater than 60 years of age. This study indicates that the difference between the two countries (in relative importance of the predictors included in this study) is mainly due to the fact that years of education is connected to age in the Western world but to sex in Bangladesh. It remains to be examined whether earlier selective survival is also responsible for the relative absence of cognitive age differences in Bangladesh.
Neural bases for basic processes in heuristic problem solving: Take solving Sudoku puzzles as an example
Authors: Qin Yulin , Xiang Jie , Wang Rifeng , Zhou Haiyan , Li Kuncheng , Zhong Ning 
Published: November 2012

AbstractNewell and Simon postulated that the basic steps in human problem‐solving involve iteratively applying operators to transform the state of the problem to eventually achieve a goal. To check the neural basis of this framework, the present study focused on the basic processes in human heuristic problem‐solving that the participants identified the current problem state and then recalled and applied the corresponding heuristic rules to change the problem state. A new paradigm, solving simplified Sudoku puzzles, was developed for an event‐related functional magnetic resonance imaging (fMRI) study in problem solving. Regions of interest (ROIs), including the left prefrontal cortex, the bilateral posterior parietal cortex, the anterior cingulated cortex, the bilateral caudate nuclei, the bilateral fusiform, as well as the bilateral frontal eye fields, were found to be involved in the task. To obtain convergent evidence, in addition to traditional statistical analysis, we used the multivariate voxel classification method to check the accuracy of the predictions for the condition of the task from the blood oxygen level dependent (BOLD) response of the ROIs, using a new classifier developed in this study for fMRI data. To reveal the roles that the ROIs play in problem solving, we developed an ACT‐R computational model of the information‐processing processes in human problem solving, and tried to predict the BOLD response of the ROIs from the task. Advances in human problem‐solving research after Newell and Simon are then briefly discussed.
Preparation and phase behavior of blends of polysulfone‐based polymers with phosphorous‐containing smectic‐A liquid crystals
Authors: Vlad‐Bubulac Tachita , Serbezeanu Diana , Hamciuc Corneliu , Petreus Oana , Carja Ionela‐Daniela , Lisa Gabriela 
Published: November 2012

AbstractPreparation and experimental studies on the phase transitions and morphology of novel polymer‐dispersed liquid crystal (PDLC) mixtures of polysulfone UDEL‐3000 (PSU) or its derivatives (chloromethylated polysulfone or polysulfone containing lateral phosphaphenanthrene substituent) and a phosphorus‐containing liquid crystalline polymer (LCC) that exhibit isotropic/nematic/smectic‐A mesophase transition were performed. The mesomorphic properties of PDLC have been investigated by differential scanning calorimetry and polarizing optical microscopy. Mesophases structures were also investigated by X‐ray diffraction measurements, the diffraction pattern being in close dependence on the polysulfone structure and PDLC composition. The effect of the phosphorus content on the thermal properties was evaluated by thermogravimetric analysis. The results reveal that the composites were stable up to 337°C in air showing initial decomposition temperatures in the range of 337–368°C and a 10% weight loss in the range of 357–397°C. The presence of P in the structure of LCC leads to higher char yields at 700°C, for PDLCs composites, increasing with the content of phosphorus‐containing polymer. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Methods for quantifying the stable sintering region in laser sintered polyamide‐12
Authors: Vasquez M. , Haworth B. , Hopkinson N. 
Published: November 2012

AbstractManufacturing complex parts by the laser sintering process requires a minimum amount of energy input for consolidation of polymer particles to occur; however too much energy can result in a decline in mechanical properties. This decrease is thought to be the result of polymer chain degradation. A stable sintering region (SSR) has been proposed to describe the optimum temperature range for successful laser sintering. This article will aim to quantify the SSR for polyamide‐12 by using thermogravimetric analysis (TGA) to provide a framework for identifying key laser sintering processing parameters. Weight loss with respect to temperature is the main measurement output of the TGA procedure. However, the precise temperature and thermal history of a material is difficult to quantify during the laser sintering process; instead an energy input approach has been developed. A degradation energy was calculated from the TGA data and was used in conjunction with a laser sintering formula called energy melt ratio to prescribe build parameters for laser sintered parts. The mechanical properties of these parts illustrated the effect of degradation at various levels of energy input. Implications for this work include optimizing the material selection process for polymer laser sintering materials beyond polyamide‐12. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Recycling of thermoset polyurethane foams
Authors: Quadrini Fabrizio , Bellisario Denise , Santo Loredana 
Published: November 2012

AbstractA new way for recycling polyurethane (PU) foams is shown by scrap pulverization and subsequent compression molding of resulting particles. The compression molding stage is also called “direct molding” to highlight the absence of any linking agent or virgin material. Large disks, 190 mm in diameter, were molded by recycling foam scraps from motorcycle seats. Aluminum alloy molds and a hot parallel press plate press were used: the molding temperature was fixed to 180°C, the molding pressure to 4.2 MPa, and the molding time to 15 min, whereas the weight of the particles to mold was changed so as to obtain disks with different thickness. The final density of molded product was close to 1 g/cm3, resulting in a compacting factor of 14 in comparison with the initial PU foam. Indentation tests and tensile tests showed that final products exhibit good mechanical performances. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Morphology, crystallization, thermal, and mechanical properties of poly(vinylidene fluoride) films filled with different concentrations of polyhedral oligomeric silsesquioxane
Authors: Liu Yizhi , Sun Yi , Zeng Fanlin , Chen Yunjun , Li Qingkun , Yu Bowen , Liu Wenjing 
Published: November 2012

AbstractNanocomposites consisting of a poly(vinylidene fluoride) (PVDF) matrix and 0–8 wt% fluoropropyl polyhedral oligomeric silsesquioxane (FP‐POSS) were obtained through the solvent evaporation method. Morphology, crystallization, as well as thermal and mechanical properties were investigated. FP‐POSS, acting as a nucleating agent, exhibited robust miscibility with PVDF, enhancing the crystallinity of PVDF. A high relative fraction of the β phase was observed in the composites. The thermal degradation of PVDF was not significantly affected by FP‐POSS under a nitrogen atmosphere. Low addition of FP‐POSS, acting as nanofiller, led to remarkable improvement in mechanical properties, including hardness. The maximum was achieved at 3 wt%. High amounts led to inferior mechanical properties. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
The influence of isosorbide on thermal properties of poly(L‐lactide) synthesized by different methods
Authors: Ristić Ivan S. , Radusin Tanja , Pilić Branka , Cakić Suzana , Budinski‐Simendić Jaroslava 
Published: November 2012

AbstractIn this article, we analyzed the influence of isosorbide content on glass transition temperature and crystallinity of poly(L‐lactide). Different synthesis methods were applied to determine optimal procedure for polymerization of L‐lactide in the presence of isosorbide. Two procedures were performed with tin(II) 2‐ethylhexanoate as the catalyst: first, using the vacuum sealed vessel, and second, using microwave reactor bulk polymerizations. The solution polymerization (with trifluoromethanesulfonic acid as catalyst) was possible at the temperature of 40°C. Obtained polyesters had number average molecular weights ranging from 20,000 to 65,000 g mol–1, according to the gel permeation chromatography measurements. The polymer structure was characterized by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy. Thermal properties of the obtained polymers were analyzed using thermogravimetry (TG) and differential scanning calorimetry (DSC). According to DSC measurements, the addition of isosorbide in the polyesters influenced the increase in both glass transition temperature and degree of crystallization for all samples. The results obtained by thermogravimetric analysis confirmed the strong influence of polymerization mechanism on synthesized poly(L‐lactides) thermal properties. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers