bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serotonin promotes acinar dedifferentiation following pancreatitis‐induced regeneration in the adult pancreas
Authors: Saponara Enrica , Grabliauskaite Kamile , Bombardo Marta , Buzzi Raphael , Silva Alberto B , Malagola Ermanno , Tian Yinghua , Hehl Adrian B , Schraner Elisabeth M , Seleznik Gitta M , Zabel Anja , Reding Theresia , Sonda Sabrina , Graf Rolf 
Published: August 2015

AbstractThe exocrine pancreas exhibits a distinctive capacity for tissue regeneration and renewal following injury. This regenerative ability has important implications for a variety of disorders, including pancreatitis and pancreatic cancer, diseases associated with high morbidity and mortality. Thus, understanding its underlying mechanisms may help in developing therapeutic interventions. Serotonin has been recognized as a potent mitogen for a variety of cells and tissues. Here we investigated whether serotonin exerts a mitogenic effect in pancreatic acinar cells in three regenerative models, inflammatory tissue injury following pancreatitis, tissue loss following partial pancreatectomy, and thyroid hormone‐stimulated acinar proliferation. Genetic and pharmacological techniques were used to modulate serotonin levels in vivo. Acinar dedifferentiation and cell cycle progression during the regenerative phase were investigated over the course of 2 weeks. By comparing acinar proliferation in the different murine models of regeneration, we found that serotonin did not affect the clonal regeneration of mature acinar cells. Serotonin was, however, required for acinar dedifferentiation following inflammation‐mediated tissue injury. Specifically, lack of serotonin resulted in delayed up‐regulation of progenitor genes and delayed the formation of acinar‐to‐ductal metaplasia and defective acinar cell proliferation. We identified serotonin‐dependent acinar secretion as a key step in progenitor‐based regeneration, as it promoted acinar cell dedifferentiation and the recruitment of type 2 macrophages. Finally, we identified a regulatory Hes1–Ptfa axis in the uninjured adult pancreas, activated by zymogen secretion. Our findings indicated that serotonin plays a critical role in the regeneration of the adult pancreas following pancreatitis by promoting the dedifferentiation of acinar cells. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Evaluation of a Weight‐based Rabbit Anti‐thymocyte Globulin Induction Dosing Regimen for Kidney Transplant Recipients
Authors: Pennington Catherine A. , Tischer Sarah M. , Lee Eliza , Lee Sun , Sindelar James , Park Jeong M. 
Published: August 2015

Study ObjectiveAlthough rabbit anti‐thymocyte globulin (rATG) is commonly used as induction therapy for kidney transplantation, dosing is not standardized. Recently available findings suggest that even subtle differences in the cumulative dose of rATG induction may have an impact on acute rejection rates for patients receiving steroid‐minimization maintenance immunosuppression. This investigation evaluated the potential consequences of rounding and capping rATG doses in patients receiving steroid‐containing maintenance immunosuppression when calculating the dose based on actual body weight.DesignSingle‐center retrospective cohort study.SettingA large academic medical center.PatientsA total of 261 adult kidney transplant recipients between July 1, 2010, and December 31, 2012, who received rATG induction and were maintained on tacrolimus, mycophenolate, and prednisone.Methods and MeasurementsIncidences of biopsy‐confirmed acute rejection, opportunistic infections and hematologic effects within 12 months posttransplant were assessed for patients receiving a cumulative rATG dose of 5 mg/kg or higher (5.2 ± 0.2 mg/kg, n=138) compared with those who received a cumulative rATG dose lower than 5 mg/kg (4.5 ± 0.6 mg/kg, n=123). The groups had similar baseline characteristics, immunologic risk, and indications for rATG induction. The incidence of clinically relevant biopsy‐confirmed acute rejection was low and similar between the groups (8.7% for rATG of 5 mg/kg or higher vs 8.9% for rATG lower than 5 mg/kg, p=0.944). Patient survival, all‐cause graft survival, and graft function did not differ between the groups. Incidences of cytomegalovirus and BK virus infection as well as the extent and duration of lymphopenia were also similar between the groups.ConclusionsIn combination with triple maintenance immunosuppression consisting of tacrolimus, mycophenolate, and prednisone, modest differences in the cumulative rATG dose were not associated with increased risk of acute rejection. Measures to optimize rATG utilization present opportunities for cost‐saving without sacrificing efficacy in this patient population.
Synthesis of optically active conjugated polymers containing platinum in the main chain: Control of the higher‐order structures by substituents and solvents
Authors: Miyagi Yu , Hirao Takehiro , Haino Takeharu , Sanda Fumio 
Published: August 2015

ABSTRACTThe Sonogashira–Hagihara coupling polymerization of d‐hydroxyphenylglycine‐derived diiodo monomers 1–4 and platinum‐containing diethynyl monomer 5 gave the corresponding polymers [poly(1–5)–(2–5)] with number‐average molecular weights of 19,000–25,000 quantitatively. The polymers were soluble in CHCl3, CH2Cl2, THF, and DMF. CD and UV–vis spectroscopic analysis revealed that amide‐substituted polymers [poly(1–5) and poly(2–5)] formed chiral higher‐order structures in solution, while ester‐substituted polymers [poly(3–5) and poly(4–5)] did not. Poly(1–5) formed one‐handed helices in THF/toluene mixtures, while it formed chiral aggregates in THF/MeOH mixtures. Poly(1–5) emitted fluorescence with quantum yields ranging from 0.8 to 1.3%. The polymers usually aggregated in the solid state. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2452–2461
Effect of side chain conjugation lengths on photovoltaic performance of two‐dimensional conjugated copolymers that contain diketopyrrolopyrrole and thiophene with side chains
Authors: Liu You‐Ren , Chan Li‐Hsin , Tang Horng‐Yi 
Published: August 2015

ABSTRACTTwo new two‐dimensional conjugated copolymers that contain diketopyrrolopyrrole and thiophene with different π conjugation lengths as side chains, called PDPPMTD and PDPPBTD, were designed and synthesized for use in polymer solar cells (PSCs). The resulting copolymers in the thin film state displayed broad absorption in the visible range with an absorption edge at over 1000 nm, and both had relatively low‐lying HOMO levels, at −5.20 and −5.18 eV for PDPPMTD and PDPPBTD, respectively. The power conversion efficiency (PCE) of the PSC that was based on PDPPBTD/PC61BM (w/w = 1:2) reached 4.10 % with a Jsc of 14.5 mA/cm2, a Voc of 0.59 V and an FF of 48%, while PDPPMTD/PC61BM (w/w = 1:2) had a PCE of 2.96% with a Jsc of 12.6 mA/cm2, a Voc of 0.60 V, and an FF of 39%. These results indicate that subtle tuning of the chemical structure can significantly influence Jsc and FF. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2878–2889
Effect of limonene on the frontal ring opening metathesis polymerization of dicyclopentadiene
Authors: Alzari Valeria , Nuvoli Daniele , Sanna Davide , Ruiu Andrea , Mariani Alberto 
Published: August 2015

ABSTRACTThe frontal ring opening metathesis polymerization (FROMP) of dicyclopentadiene (DCPD) in the presence of limonene, using second generation Grubbs’ catalysts, is reported. The effect of limonene on the amount of catalyst and the typical frontal polymerization parameters, as maximum temperature (Tmax) and velocity of the front (Vf), is studied. In addition, the influence of limonene on the mechanical properties of the polymeric samples is reported. Finally, a deep study on the swelling properties of polymers is done. It has been demonstrated that limonene acts as both inhibitor and solvent of the catalyst. The Tmax, Vf, Tg, and Young modulus values decrease as the amount of limonene increases, and the polymer samples swell in THF depending on the amount of limonene. All results indicate that the limonene addition on FROMP of results in advantages on the polymerization reaction and its parameters and on the final polymer properties. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 63–68
Energy coupling mechanisms of MFS transporters
Authors: Zhang Xuejun C. , Zhao Yan , Heng Jie , Jiang Daohua 
Published: August 2015

AbstractMajor facilitator superfamily (MFS) is a large class of secondary active transporters widely expressed across all life kingdoms. Although a common 12‐transmembrane helix‐bundle architecture is found in most MFS crystal structures available, a common mechanism of energy coupling remains to be elucidated. Here, we discuss several models for energy‐coupling in the transport process of the transporters, largely based on currently available structures and the results of their biochemical analyses. Special attention is paid to the interaction between protonation and the negative‐inside membrane potential. Also, functional roles of the conserved sequence motifs are discussed in the context of the 3D structures. We anticipate that in the near future, a unified picture of the functions of MFS transporters will emerge from the insights gained from studies of the common architectures and conserved motifs.
Protein structure refinement via molecular‐dynamics simulations: What works and what does not?
Authors: Feig Michael , Mirjalili Vahid 
Published: August 2015

ABSTRACTProtein structure refinement during CASP11 by the Feig group was described. Molecular dynamics simulations were used in combination with an improved selection and averaging protocol. On average, modest refinement was achieved with some targets improved significantly. Analysis of the CASP submission from our group focused on refinement success versus amount of sampling, refinement of different secondary structure elements and whether refinement varied as a function of which group provided initial models. The refinement of local stereochemical features was examined via the MolProbity score and an updated protocol was developed that can generate high‐quality structures with very low MolProbity scores for most starting structures with modest computational effort. Proteins 2016; 84(Suppl 1):282–292. © 2015 Wiley Periodicals, Inc.
Heat dissipation and its relation to molecular orbital energies in single‐molecule junctions
Authors: Naimi Yaghoob , Vahedi Javad 
Published: August 2015

AbstractWe present a theoretical study of the heat dissipation in single‐molecule junctions. In order to investigate the heat dissipation in the electrodes and the relationship between the transmission spectra and the electronic structures, we consider a toy model in which electrodes are linked by a two‐level molecular bridge. By using the Landauer approach, we show how heat dissipation in the electrodes of a molecular junction is related to its transmission characteristics. We show that in general, heat is not equally dissipated in the left and right electrodes of the junction and it depends on the bias polarity and the positions of the molecule's energy levels with respect to the Fermi level. Also, we exploit the molecule as a junction and the results show a good agreement with the toy model. Our results for the heat dissipation are remarkable in the sense that they can be used to detect which energy levels of a junction are dominated in the transport process.
Importance of coordination number and bond length in titanium revealed by electronic structure investigations
Authors: Huang Liang‐Feng , Grabowski Blazej , McEniry Eunan , Trinkle Dallas R. , Neugebauer Jörg 
Published: August 2015

AbstractWe study the influence of coordination number and bond length on the phase stability and orbital occupation in Ti using density functional theory. In particular, Ti under a wide range of conditions (equilibrium state, hydrostatic pressure, anisotropic strain, and phase transformations) is systematically investigated allowing us to derive generic energetic and electronic trends. Our analysis of the correlations between electronic structure and the atomic geometry reveals that the most suitable descriptors of the system are an effective coordination number and an effective bond length. Utilizing these descriptors, we show that (i) the phase stability of Ti increases with coordination number, because of the increased number of interatomic bonds; (ii) the occupation number of the d (s and p) orbital decreases (increases) with increasing the bond length, because of the localized (delocalized) character of the d (p and s) orbital. These dependencies are particularly evident after applying a simple harmonic strain correction to the energy and an electron‐transfer correction within the phase. The physical picture derived from pure Ti is used to explain the phase stability and orbital occupation of Ti–Nb and Ti–Zr alloys, which reveals the underlying mechanisms for various experimental phenomena in Ti alloys.
Electronic structure and magnetic properties of an iron‐ and tantalum‐based double perovskite
Authors: He Ying‐Fang , Shao Bin 
Published: August 2015

AbstractBased on density functional theory, the dynamic stability, electronic structure, and magnetic properties of a LiNbO3 ‐type double perovskite (A2BB′O6), Zn2 FeTaO6, have been studied. Results show that the experimental structure is dynamic stabilized with a spontaneous polarization of 57C cm−2 along the c‐axis. By using GGA+U method, the system is predicted to be a charge transfer type insulator with 4.3 magnetic moment on Fe ion. The easy axis is in the ab‐plane. Calculations on exchange integrals indicate that the magnetic coupling between Fe ions of the Fe–O–Ta–O–Fe bridge is very weak. However, the AFM coupling of the Fe–O–Fe bridge is much stronger, which suggests a potential way to design magnetoelectric materials in ferrimagnetic phase with 3d and 5d ions at B‐ and ‐site in the LiNbO3 double perovskite system.
Specification of Flows for Flushing Surficial Sand from Cobble Riffles
Authors: James C. S. 
Published: August 2015

AbstractMaintenance of habitat for benthic organisms and fish spawning may require flushing of sand from gravel or cobble river beds. An approach is proposed for specifying both the magnitude and duration of flow necessary to scour sand to a desired depth over a specified length of riffle bed. Scour is assumed to begin at the upstream end of the reach to be flushed and to progress downstream. The flow magnitude necessary for scour to an equilibrium depth was found from previously published laboratory data to be related to the median sand grain size and its movability number (the ratio of shear velocity to settling velocity). The required flow duration is determined by the time for scour to progress over the specified distance. The progression rate was determined through new laboratory experiments to be related to the flow velocity and depth, the distance advanced, the sand movability number and the channel slope. Application of the approach is illustrated by example. Copyright © 2015 John Wiley & Sons, Ltd.
Learning to collaborate through collaboration: How allying with expert firms influences collaborative innovation within novice firms
Authors: Howard Michael , Steensma H. Kevin , Lyles Marjorie , Dhanaraj Charles 
Published: August 2015

Research summary: Strategic alliances have been recognized as a means for firms to learn their partners' proprietary knowledge; such alliances are also valuable opportunities for partner firms to learn tacit organizational routines from their counterparts. We consider how relatively novice technology firms can learn intraorganizational collaborative routines from more experienced alliance partners and then deploy them independently for their own innovative pursuits. We examine the alliance relationships between Eli Lilly & Co. (Lilly), a recognized expert in collaborative innovation, and 55 small biotech partner firms. Using three levels of analysis (firm, patent, and inventor dyad), we find that greater social interaction between the partner firm and Lilly subsequently increases internal collaboration among the partner firm's inventors.Managerial summary: Can collaborating externally advance internal collaboration? Yes. Our research found that collaboration among scientists at small, early‐stage biotechnology firms significantly increased after these firms formed highly interactive R&D alliances with a large pharmaceutical company known for its expertise in such collaboration. It is well known that alliances help new firms learn specific new technologies and commercialize innovations. Our study broadens the scope of potential benefits of alliances. New firms can also learn collaboration techniques, deploying them internally to enhance their own abilities in collaborative innovation. Managers should take this additional benefit into consideration in developing their alliance strategies. Pursuing alliance partners with expertise in collaboration and keeping a high level of mutual interactions with partner firm personnel should be important considerations to extract this value. Copyright © 2015 John Wiley & Sons, Ltd.
A practical guide to text mining with topic extraction
Authors: Karl Andrew , Wisnowski James , Rushing W. Heath 
Published: August 2015

Text analytics continue to proliferate as mass volumes of unstructured but highly useful data are generated at unbounded rates. Vector space models for text data—in which documents are represented by rows and words by columns—provide a translation of this unstructured data into a format that may be analyzed with statistical and machine learning techniques. This approach gives excellent results in revealing common themes, clustering documents, clustering words, and in translating unstructured text fields (such as an open‐ended survey response) to usable input variables for predictive modeling. After discussing the collection and processing of text, we explore properties and transformations of the document‐term matrix (DTM). We show how the singular value decomposition may be used to drastically reduce the size of the document space while also setting the stage for automatic topic extraction, courtesy of the varimax rotation. This latent semantic analysis (LSA) approach produces factors that are compatible with graphical exploration and advanced analytics. We also explore Latent Dirichlet Allocation for topic analysis. We reference published R packages to implement the methods and conclude with a summary of other popular open‐source and commercial software packages. WIREs Comput Stat 2015, 7:326–340. doi: 10.1002/wics.1361This article is categorized under:

Statistical Learning and Exploratory Methods of the Data Sciences > Clustering and Classification
Statistical Learning and Exploratory Methods of the Data Sciences > Pattern Recognition
Statistical Learning and Exploratory Methods of the Data Sciences > Text Mining
Modified Anterior Approach for the ALPPS Procedure: How We Do It
Authors: Chan Albert C. Y. , Poon Ronnie T. P. , Lo Chung Mau 
Published: August 2015

AbstractBackgroundAssociating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a highly complex operation that demands a thorough understanding of the intrahepatic vascular anatomy and skills in parenchymal transection for the in situ split procedure. In order to minimize adhesion formation after the stage I operation and to avoid iatrogenic tumor rupture during right liver mobilization in large tumors, anterior approach appears to be a logical approach for the in situ split procedure. However, in contrast to the anterior approach adopted for the usual right hepatectomy, the right hepatic artery and biliary pedicle remain intact and undivided during the first operation. To address this issue, we hereby reported our experience of the modified ‘anterior approach’ for the ALPPS procedure that facilitates a complete in situ parenchymal split.MethodsProspectively collected data of 13 patients who underwent the ALPPS procedure by the modified anterior approach for hepatocellular carcinoma from October 2013 to October 2014 were reviewed.ResultsThe baseline future liver remnant volume (FLR) was 286 ml. The median tumor size was 6.0 cm. After a median of 8 days from stage I operation, the left FLR hypertrophied by 52.7 % in volume to 482 ml. All patients proceeded to second stage hepatectomy (extended right hepatectomy, n = 5; right hepatectomy, n = 6; right trisectionectomy, n = 2) without significant adhesion encountered. The overall morbidity and mortality rates were 7.7 % (n = 1) and 7.7 % (n = 1), respectively.ConclusionThe modified anterior approach is safe and feasible for complete in situ split in the ALPPS procedure.
Additional Imaging in Alert Trauma Patients with Cervical Spine Tenderness and a Negative Computed Tomographic Scan: Is it Needed?
Authors: Mavros Michael N. , Kaafarani Haytham M. A. , Mejaddam Ali Y. , Ramly Elie P. , Avery Laura , Fagenholz Peter J. , Yeh D. Dante , de Moya Marc A. , Velmahos George C. 
Published: August 2015

AbstractBackgroundThe value of additional imaging in clearing the cervical spine (C‐spine) of alert trauma patients with tenderness on clinical exam and a negative computed tomographic (CT) scan is still unclear.MethodsAll adult trauma patients with a Glasgow Coma Scale of 15, C‐spine tenderness in the absence of neurologic signs, and a negative C‐spine CT were included. The study period extended from September 2011 to June 2012. C‐spine CT scans were interpreted in detail and considered negative in the absence of any findings indicating bony, ligamentous, or soft tissue injury around the C‐spine. The incidence of C‐spine injury was evaluated using early (<24 h) repeat physical examination, MRI, and/or flexion–extension films.ResultsOf 2015 patients with a C‐spine CT, 383 (19 %) fulfilled the inclusion criteria. The median age was 43 (IQR: 30–53) and 44.7 % were female. Thirty‐six patients (9.4 %) underwent MRI (3.7 %), flexion–extension imaging (5.2 %), or both (0.5 %), with no significant injuries identified and subsequent removal of the collar allowed. The remaining patients were clinically cleared within 24 h of presentation. None of the patients developed neurological signs following removal of the collar. On bivariate analysis, no variable except for evaluation by trauma surgery was associated with performance of additional imaging.ConclusionC‐spine precautions can be withdrawn without additional imaging in most blunt trauma patients with C‐spine tenderness but negative neurologic evaluation and C‐spine CT. Focus should be placed on the detailed and comprehensive interpretation of the C‐spine CT.