bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving outcome for patients with pancreatic cancer through centralization
Authors: Lemmens V E P P , Bosscha K , van der Schelling G , Brenninkmeijer S , Coebergh J W W , de Hingh I H J T 
Published: June 2011

Abstract

Background
High-volume institutions are associated with improved clinical outcomes for pancreatic cancer. This study investigated the impact of centralizing pancreatic cancer surgery in the south of the Netherlands.

Methods
All patients diagnosed in the Eindhoven Cancer Registry area in 1995–2000 (precentralization) and 2005–2008 (implementation of centralization agreements) with primary cancer of the pancreatic head, extrahepatic bile ducts, ampulla of Vater or duodenum were included. Resection rates, in-hospital mortality, 2-year survival and changes in treatment patterns were analysed. Multivariable regression analyses were used to identify independent risk factors for death.

Results
Some 2129 patients were identified. Resection rates increased from 19·0 to 30·0 per cent (P &lt; 0·001). The number of hospitals performing resections decreased from eight to three, and the annual number of resections per hospital increased from two to 16. The in-hospital mortality rate dropped from 24·4 to 3·6 per cent (P &lt; 0·001) and was zero in 2008. The 2-year survival rate after surgery increased from 38·1 to 49·4 per cent (P = 0·001), and the rate irrespective of treatment increased from 10·3 to 16·0 per cent (P &lt; 0·001). There was no improvement in 2-year survival in non-operated patients. After adjustment for relevant patient and tumour factors, those undergoing surgery more recently had a lower risk of death (hazard ratio 0·70, 95 per cent confidence interval 0·51 to 0·97). Changes in surgical patterns seemed largely to explain the improvements.

Conclusion
High-quality care can be achieved in regional hospitals through collaboration. Centralization should no longer be regarded as a threat by general hospitals but as a chance to improve outcomes in pancreatic cancer.
Long-term functional results and quality of life after transanal endoscopic microsurgery
Authors: Allaix M E , Rebecchi F , Giaccone C , Mistrangelo M , Morino M 
Published: June 2011

Abstract

Background
Of the few studies that have investigated quality-of-life (QoL) outcomes after transanal endoscopic microsurgery (TEM), the majority have reported only short-term follow-up data. This study assessed long-term clinical and instrumental outcomes (QoL, sexual, urinary and sphincter function) after TEM for extraperitoneal rectal cancer.

Methods
Preoperative and postoperative anorectal function was assessed in consecutive patients with benign rectal lesions or early rectal cancer, based on clinical scores and anorectal manometry.

Results
Between January 2000 and July 2005, 93 patients undergoing TEM completed the 60-month study protocol. The mean Wexner continence score increased from baseline at 3 months, began to decline within 12 months, and had returned to the preoperative value at 60 months. Urgency was reported by 65·0, 30·0 and 5 per cent of patients at 3, 12 and 60 months respectively (P &lt; 0·050). A significant improvement was noted in various clinical and QoL scores at 12 and 60 months. Postoperative manometry values at 3 months were significantly lower than at baseline (P &lt; 0·050), but had returned to preoperative values at 12 months. Tumour size of 4 cm or above was the only factor that significantly (P = 0·008) affected the rectal sensitivity threshold, the urge to defaecate threshold and the maximum tolerated volume at 3 months after TEM.

Conclusion
TEM had no long-term effect on anorectal function or QoL. Lower anal resting pressure at early follow-up was not associated with defaecation problems in patients who were continent before surgery.
Long-term results after laparoscopic reoperation for failed antireflux procedures
Authors: Dallemagne B , Arenas Sanchez M , Francart D , Perretta S , Weerts J , Markiewicz S , Jehaes C 
Published: June 2011

Abstract

Background
Surgery for failed antireflux procedures is technically more demanding than primary fundoplication. The success rate does not equal that of the primary procedures. This retrospective analysis aimed to assess long-term subjective and objective outcomes in patients who underwent laparoscopic surgery for fundoplication failure.

Methods
Objective and subjective outcomes were assessed by radiological and endoscopic methods, symptom questionnaire and quality-of-life index at a minimum follow-up of 12 (mean 75·8) months.

Results
The study included 129 consecutive patients who had laparoscopic redo surgery after fundoplication had failed. The most frequent patterns of failure were hiatal herniation (50 patients) and slippage (45). Resolution of the symptoms that led to redo surgery was achieved in 27 of 37 and 11 of 16 patients operated for recurrence and for dysphagia respectively. Objective failure was demonstrated in 16 of 39 patients with herniation and six of 22 with slippage. Seven patients underwent an additional surgical procedure.

Conclusion
Long-term assessment of objective and subjective results after laparoscopic repair for failed fundoplication revealed a high failure rate that increased with the length of follow-up. Unexpected and untreated oesophageal shortening may be responsible for this failure rate.
Comparison of open and laparoscopic live donor left lateral sectionectomy
Authors: Kim K H , Jung D H , Park K M , Lee Y J , Kim D Y , Kim K M , Lee S G 
Published: June 2011

Abstract

Background
The present study was undertaken to determine whether laparoscopic live donor left lateral sectionectomy (LLS) in paediatric liver transplantation is a feasible, safe and reproducible procedure, compared with open live donor left lateral sectionectomy (OLS).

Methods
A retrospective review was conducted of all consecutive live donor procedures for paediatric liver transplantation performed between May 2008 and October 2009. All live donor hepatectomies were carried out by a single surgeon.

Results
A total of 26 live donor procedures for paediatric liver transplantation were performed, of which 11 were LLS and 11 OLS; four left hepatectomies were excluded. The LLS group had a significantly shorter hospital stay (mean(s.d.) 6·9(0·3) versus 9·8(0·9) days; P = 0·001) and time to oral diet (2·1(0·3) versus 2·7(0·4) days; P = 0·012). Duration of operation, blood loss, warm ischaemia time and out-of-pocket medical costs were comparable between groups. There was no death in either donor group and only one complication, a wound seroma, in the OLS group.

Conclusion
LLS seemed to be a safe, feasible and reproducible procedure, and was associated with reduced hospital stay.
Methodology for determining major constituents of ayahuasca and their metabolites in blood
Authors: McIlhenny Ethan H. , Riba Jordi , Barbanoj Manel J. , Strassman Rick , Barker Steven A. 
Published: June 2011

ABSTRACTThere is an increasing interest in potential medical applications of ayahuasca, a South American psychotropic plant tea with a long cultural history of indigenous medical and religious use. Clinical research into ayahuasca will require specific, sensitive and comprehensive methods for the characterization and quantitation of these compounds and their metabolites in blood. A combination of two analytical techniques (high‐performance liquid chromatography with ultraviolet and/or fluorescence detection and gas chromatography with nitrogen–phosphorus detection) has been used for the analysis of some of the constituents of ayahuasca in blood following its oral consumption. We report here a single methodology for the direct analysis of 14 of the major alkaloid components of ayahuasca, including several known and potential metabolites of N,N‐dimethyltryptamine and the harmala alkaloids in blood. The method uses 96‐well plate/protein precipitation/filtration for plasma samples, and analysis by HPLC–ion trap–ion trap–mass spectrometry using heated electrospray ionization to reduce matrix effects. The method expands the list of compounds capable of being monitored in blood following ayahuasca administration while providing a simplified approach to their analysis. The method has adequate sensitivity, specificity and reproducibility to make it useful for clinical research with ayahuasca. Copyright © 2011 John Wiley & Sons, Ltd.
Sustainable Development of Maritime Operations in Ports
Authors: Dinwoodie John , Tuck Sarah , Knowles Harriet , Benhin James , Sansom Mark 
Published: June 2011

ABSTRACTGlobalisation has heralded burgeoning ship movements and maritime operations in ports alongside increased international concerns regarding potential environmental impacts. In particular, smaller ports require accessible tools to manage them. A framework to facilitate environmental management applies business process principles to identify relevant inputs, processes and outputs. A case study of Falmouth Harbour Commissioners compares functional units and flows that define input–output processes for anchoring and bunkering operations. Strategic‐level processes affect present and future operations while tactical service processes guarantee service level and quality through their integrity. Operational processes occur at the output level. An accessible generic framework supports planning of more sustainable maritime operations, facilitates mitigation of potential risks and encourages authorities to engage with sustainability agendas and manage development proposals proactively. Ongoing interlocution with business strategists will refocus port managers on educational and commercial missions and increase stakeholder engagement. Simplification and optimisation phases of business process re‐engineering remain untapped by business strategists. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment.
Finite element implementation for computer‐aided education of structural mechanics: Frame analysis
Authors: Lee Jae Young , Ahn Sung Youll 
Published: June 2011

AbstractInstructional tools for the computer‐aided education of structural analysis have been implemented as an extension of a finite element analysis program, VisualFEA. They are devised to promote understanding in structural analysis, and stimulate interest in the subject by substantiating the conceptual principles and visually exhibiting the complex computational processes with the aid of interactive computer graphics. In lieu of manipulation with pre‐supplied conditions or the input of assumed data, the instructional tools are operated through a real and practical process of structural analysis from the creation of modeling data to the presentation of solution results. The basic principles, computing formulae, and methods of analysis in structural mechanics are simulated for instructional purposes on the basis of finite element technology. VisualFEA has a number of educational functions for use in teaching and learning structural analysis. Among them, only those related to frame analysis are introduced in this article. There are numerous programs for frame analysis. However, the educational features described in this article are not common in any other programs for similar purposes. © 2011 Wiley Periodicals, Inc. Comput Appl Eng Educ 22:387–409, 2014; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.10.1002/cae.20563
Iminodipropionic Acid as the Leaving Group for DNA Polymerization by HIV‐1 Reverse Transcriptase
Authors: Song Xiao‐Ping , Bouillon Camille , Lescrinier Eveline , Herdewijn Piet 
Published: June 2011

AbstractPrevious studies have demonstrated that some selected amino monoacids and amino diacids can function as leaving groups in the polymerase‐catalyzed incorporation of deoxynucleotides into DNA. Among these, the iminodiacetic acid phosphoramidate of deoxyadenosine monophosphate (IDA‐dAMP) represents an interesting example, as it could overcome some of the problems observed when using L‐aspartic acid as the leaving group, that is, poor chain elongation. We have now synthesized and evaluated a series of IDA‐dAMP analogues that bear either an extended aliphatic chain in the amino acid function, or a phosphonic acid moiety (substituting for the carboxylic acid function). Among these compounds, the nucleotide with an iminodipropionic acid leaving group (IDP‐dAMP) was identified as the best substrate; the excellent single incorporation (91 % conversion to a P+1 strand at 50 μM) was at a substrate concentration ten times lower than that used for IDA‐dAMP). This nucleotide also presented improved kinetics and elongation capability compared to IDA‐dAMP. The analogues with T, G, and C base moieties were also investigated for their incorporation ability with HIV‐1 RT. The incorporation efficiency was found to decrease in the order A>T>G>C. The properties of the iminodipropionic acid as the leaving group surpass those of previously evaluated leaving groups; this acid will be a prime candidate for in vivo testing.
Glycosynthase‐Mediated Assembly of Xylanase Substrates and Inhibitors
Authors: Goddard‐Borger Ethan D. , Fiege Brigitte , Kwan Emily M. , Withers Stephen G. 
Published: June 2011

AbstractAn exo‐β‐xylosidase mutant with glycosynthase activity was created to aid in the synthesis of xylanase substrates and inhibitors. Simple monosaccharides were easily elaborated into di‐, tri‐ and tetrasaccharides by using this enzyme. Some products proved to be surprisingly potent inhibitors of xylanases from glycoside hydrolase families 10 and 11.
High‐Temperature Produced Catalytic Sites Selective for n‐Alkane Dehydrogenation in Acid Zeolites: The Case of HZSM‐5
Authors: Al‐majnouni Khalid A. , Yun Jang Ho , Lobo Raul F. 
Published: June 2011

AbstractThe effect of high‐temperature treatment on the catalytic activity and selectivity of two HZSM5 samples has been investigated by using propane activation as the test reaction. The samples have been characterized by using X‐ray powder diffraction, nitrogen adsorption, FTIR spectroscopy, and ammonia temperature‐programmed desorption (TPD). Before high‐temperature treatment, the samples have activation energies and selectivity toward propane cracking versus dehydrogenation comparable with similar samples reported in the literature. After high‐temperature treatment (825 °C in N2), the sample’s microporous and crystalline structure remains nearly intact, but a clear decrease in the number of Brønsted‐acid sites is detected by using FTIR and ammonia TPD. Despite the decrease (≈70 %), the rate of reaction is about the same before and after heating. The selectivity toward dehydrogenation, however, increases by at least a factor of 2, whereas the activation energy for dehydrogenation decreases considerably. This is evidence that new catalytic sites are formed upon dehydroxylation. By using naphthalene as a probe molecule, it is shown that the new sites have the ability to form stable radical cations out of the neutral naphthalene, which suggests that the new sites activate propane by a redox mechanism. The kinetic isotope effect on the rate of dehydrogenation is also consistent with a redox process. The effect of heating in an oxygen atmosphere at lower temperatures was also investigated and only minor effects on reaction rates and selectivity were observed. Naphthalene adsorption experiments on oxygen‐treated samples, however, produce more radical cations than on the samples treated at high temperatures, a result that does not correlate with the dehydrogenation activity of oxygen‐treated samples.
Probing the Dynamics of CO2 and CH4 within the Porous Zirconium Terephthalate UiO‐66(Zr): A Synergic Combination of Neutron Scattering Measurements and Molecular Simulations
Authors: Yang Qingyuan , Jobic Hervé , Salles Fabrice , Kolokolov Daniil , Guillerm Vincent , Serre Christian , Maurin Guillaume 
Published: June 2011

AbstractQuasi‐elastic neutron scattering (QENS) measurements combined with molecular dynamics (MD) simulations were conducted to deeply understand the concentration dependence of the self‐ and transport diffusivities of CH4 and CO2, respectively, in the humidity‐resistant metal–organic framework UiO‐66(Zr). The QENS measurements show that the self‐diffusivity profile for CH4 exhibits a maximum, while the transport diffusivity for CO2 increases continuously at the loadings explored in this study. Our MD simulations can reproduce fairly well both the magnitude and the concentration dependence of each measured diffusivity. The flexibility of the framework implemented by deriving a new forcefield for UiO‐66(Zr) has a significant impact on the diffusivity of the two species. Methane diffuses faster than CO2 over a broad range of loading, and this is in contrast to zeolites with narrow windows, for which opposite trends were observed. Further analysis of the MD trajectories indicates that the global microscopic diffusion mechanism involves a combination of intracage motions and jump sequences between tetrahedral and octahedral cages.
Synthesis and Photophysics of Silicon Phthalocyanine–Perylenebisimide Triads Connected through Rigid and Flexible Bridges
Authors: Céspedes‐Guirao F. Javier , Martín‐Gomis Luis , Ohkubo Kei , Fukuzumi Shunichi , Fernández‐Lázaro Fernando , Sastre‐Santos Ángela 
Published: June 2011

AbstractThree new bisperylenebisimide–silicon phthalocyanine triads [(PBI)2–SiPcs 1, 2, and 3] connected with either rigid or flexible bridges were synthesized and characterized. A new synthetic approach to connect SiPc and PBI moieties through click chemistry produced triad 3 with an 80 % yield. In (PBI)2–SiPc 1, PBI and SiPc are orthogonal and were connected with a rigid connector; triads 2 and 3 bear flexible aliphatic bridges, resulting in a tilted (2) or nearly parallel arrangement (3) of PBI and SiPc. Photoinduced intramolecular processes in these (PBI)2–SiPcs were studied and the results are compared with those of the reference compounds SiPc‐ref and PBI‐ref. The occurrence of electron‐transfer processes between the SiPc and PBI units was confirmed by time‐resolved emission and transient absorption techniques. Charge‐separated (CS) states with lifetimes of 0.91, 1.3 and 2.0 ns for triads 1, 2, and 3, respectively, were detected using femtosecond laser flash photolysis. Upon the addition of Mg(ClO4)2, an increase in the lifetime of the CS states to 59, 110 and 200 μs was observed for triads (PBI)2–SiPcs 1, 2, and 3, respectively. The energy of the CS state (SiPc.+–PDI.−/Mg2+) is lower than the energy of both silicon phthalocyanine (3SiPc*–PDI) and perylenebisimide (SiPc–3PDI*) triplet excited states, which decelerates the metal ion‐decoupled electron‐transfer process for charge recombination to the ground state, thus increasing the lifetime of the CS state. The photophysics of the three triads demonstrate the importance of the rigidity of the spacer and the orientation between donor and acceptor units.
Meaningful Structural Descriptors from Charge Density
Authors: Stalke Dietmar 
Published: June 2011

AbstractThis paper provides a short introduction to the basics of electron density investigations. The two predominant approaches for the modelling and various interpretations of electron density distributions are presented. Their potential translations into chemical concepts are explained. The focus of the article lies on the deduction of chemical properties from charge density studies in some selected main group compounds. The relationship between the obtained numerical data and commonly accepted simple chemical concepts unfortunately is not always straightforward, and often the chemist relies on heuristic connections rather than rigorously defined ones. This article tries to demonstrate how charge density analyses can shed light on aspects of chemicalbondingandreactivityresulting from the determined bonding situation. Sometimes this helps to identify misconceptions and sets the scene for new unconventional synthetic approaches.
A New Phosphine Oxide Host based on ortho‐Disubstituted Dibenzofuran for Efficient Electrophosphorescence: Towards High Triplet State Excited Levels and Excellent Thermal, Morphological and Efficiency Stability
Authors: Han Chunmiao , Xie Guohua , Li Jing , Zhang Zhensong , Xu Hui , Deng Zhaopeng , Zhao Yi , Yan Pengfei , Liu Shiyong 
Published: June 2011

AbstractAn efficient host for blue and green electrophosphorescence, 4,6‐bis(diphenylphosphoryl)dibenzofuran (o‐DBFDPO), with the structure of a short‐axis‐substituted dibenzofuran was designed and synthesised. It appears that the greater density of the diphenylphosphine oxide (DPPO) moieties in the short‐axis substitution configuration effectively restrains the intermolecular interactions, because only very weak π–π stacking interactions could be observed, with a centroid‐to‐centroid distance of 3.960 Å. The improved thermal stability of o‐DBFDPO was corroborated by its very high glass transition temperature (Tg) of 191 °C, which is the result of the symmetric disubstitution structure. Photophysical investigation showed o‐DBFDPO to be superior to the monosubstituted derivative, with a longer lifetime (1.95 ns) and a higher photoluminescent quantum efficiency (61 %). The lower first singlet state excited level (3.63 eV) of o‐DBFDPO demonstrates the stronger polarisation effect attributable to the greater number of DPPO moieties. Simultaneously, an extremely high first triplet state excited level (T1) of 3.16 eV is observed, demonstrating the tiny influence of short‐axis substitution on T1. The improved carrier injection ability, which contributed to low driving voltages of blue‐ and green‐emitting phosphorescent organic light‐emitting diodes (PHOLEDs), was further confirmed by Gaussian calculation. Furthermore, the better thermal and morphological properties of o‐DBFDPO and the matched frontier molecular orbital (FMO) levels in the devices significantly reduced efficiency roll‐offs. Efficient blue and green electrophosphorescence based on the o‐DBFDPO host was demonstrated.
Facile Synthesis of Wide‐Bandgap Fluorinated Graphene Semiconductors
Authors: Chang Haixin , Cheng Jinsheng , Liu Xuqing , Gao Junfeng , Li Mingjian , Li Jinghong , Tao Xiaoming , Ding Feng , Zheng Zijian 
Published: June 2011

AbstractThe bandgap opening of graphene is extremely important for the expansion of the applications of graphene‐based materials into optoelectronics and photonics. Current methods to open the bandgap of graphene have intrinsic drawbacks including small bandgap openings, the use hazardous/harsh chemical oxidations, and the requirement of expensive chemical‐vapor deposition technologies. Herein, an eco‐friendly, highly effective, low‐cost, and highly scalable synthetic approach is reported for synthesizing wide‐bandgap fluorinated graphene (F‐graphene or or fluorographene) semiconductors under ambient conditions. In this synthesis, ionic liquids are used as the only chemical to exfoliate commercially available fluorinated graphite into single and few‐layer F‐graphene. Experimental and theoretical results show that the bandgap of F‐graphene is largely dependent on the F coverage and configuration, and thereby can be tuned over a very wide range.
Segmental Dynamics of PEO/LiClO4 Complex Crystals and Their Influence on the Li+‐Ion Transportation in Crystal Lattices: A 13C Solid‐State NMR Approach
Authors: Gao Yangwen , Hu Bingweng , Yao Yefeng , Chen Qun 
Published: June 2011

AbstractThe structure and chain dynamics of polyethylene oxide (PEO)/LiClO4 complex crystals were studied by employing state‐of‐the‐art solid‐state 13C NMR techniques. Remarkable helical jump motions of the PEO segments in the complex crystals at ambient temperatures were clearly demonstrated. The jump motions are believed to induce the transportation of the coordinated Li+ ions along the crystallographic c axis, providing a novel mechanism of ionic conductivity of the complex crystals. In addition, this work also shows that solid‐state high‐resolution 13C NMR spectroscopy can be a powerful and general tool for elucidating phase structures, dynamics, and subsequently the conduction mechanism of crystalline polymer electrolytes.