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Enantioselective Synthesis,(Chir)optical Properties,and Postsynthetic Functionalization of Furan-Containing Oxa[5]-,Oxa[6]-,and Dioxa[6]helicenes

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CCS Chemistry 2024年第10期6卷 2439-2451页

作者： Wei Fu Valentina Pelliccioli Raquel Casares-López juan M.Cuerva Martin Simon Christopher golz manuel Alcarazo Institut für Organische und Biomolekulare Chemie Georg-August-Universität Göttingen37077 Göttingen Departamento de Química Orgánica Universidad de GranadaUnidad de Excelencia Química Aplicada a Biomedicina y MedioambienteE-18071 Granada

An expedient synthesis of a series of configurationally stable oxa[5]helicenes,oxa[6]helicenes,and dioxa[6]helicenes has been developed using an intramolecular,highly enantioselective,Au-catalyzed,alkyne hydroarylation *** absolute configuration of the newly prepared structures has been established by crystallography,their inversion barriers have been determined theoretically and experimentally,and their chiroptical properties have been *** of these data with those reported for thia-or carbohelicenes sharing an otherwise identical helical framework enables the establishment of comprehensive correlations between the nature of the embedded(hetero)atom(s)and the magnitude of these *** studies on the postsynthetic functionalization of the oxahelicenes obtained are also ***,siteselective bromination at the 15-position in oxa[5]helicene 5d allows its subsequent manipulation into pyridine-containing aza-oxa[7]helicene 13d;while the two termini of oxa[6]helicene 7d have been intramolecularly cyclised into the pleiadeno[1,12,11-bcde]benzofuran derivative 15d by acidic *** transformations take place without erosion of the enantiopurity.

关键词： Au-catalysis enantioselective synthesis oxa[n]helicenes racemization dynamics postsynthetic functionalization

Arabidopsis SWC4 Binds DNA and Recruits the SWR1 Complex to Modulate Histone H2A.Z Deposition at Key Regulatory genes

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Molecular Plant 2018年第6期11卷 815-832页

作者： Angeles gomez-Zambrano Pedro Crevillen Jose M. Franco-Zorrilla juan A. Lopez Jordi Moreno-Romero Pawel Roszak juan Santos-gonzalez Silvia Jurado Jesus Vazquez Claudia Kohler Roberto Solano manuel Pineiro Jose A. Jarillo Centro de Biotecnologia y genomica de Plantas Universidad Politecnica de Madrid (UPM) - Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA) Campus Montegancedo UPM Pozuelo de Alarcon 28223 Madrid Spain Plant Molecular genetics Department and genomics Unit Centro Nacional de Biotecnologia Consejo Superior de Investigaciones Cientfficas 28049 Madrid Spain Proteomics Unit Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) 28029 Madrid Spain Department of Plant Biology Uppsala BioCenter Swedish University of Agricultural Sciences and Linnean Center for Plant Biology Uppsala 75652 Sweden Laboratory of Cardiovascular Proteomics Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC) 28029 Madrid Spain Instituto de Bioquimica Vegetal y Fotosintesis Consejo Superior de Investigaciones Cientfficas and Universidad de Sevilla 41092 Sevilla Spain Centre for Research in Agricultural genomics (CRAg) CSIC-IRTA-UAB-UB Campus UAB Bellaterra Barcelona Spain The Sainsbury Laboratory Cambridge CB2 1LR UK

Deposition of the H2A.Z histone variant by the SWR1 complex （SWRI-C） in regulatory regions of specific loci modulates transcription. Characterization of mutations in Arabidopsis thaliana homologs of yeast SWRI-C has revealed a role for H2A.Z exchange in a variety of developmental processes. Nevertheless, the exact composition of plant SWRI-C and how it is recruited to target genes remains to be established. Here we show that SWC4, the Arabidopsis homolog of yeast SANT domain protein Swc4/Eaf2, is a DNA-binding protein that interacts with SWR1-C subunits. We demonstrate that the swc4-1 knockout mutant is embryo- lethal, while SWC4 RNAi knockdown lines display pleiotropic phenotypic alterations in vegetative and repro- ductive traits, including acceleration of flowering time, indicating that SWC4 controls post-embryonic processes. Transcriptomic analyses and genome-wide profiling of H2A.Z indicate that SWC4 represses tran- scription of a number of genes, including the floral integrator FT and key transcription factors, mainly by modulating H2A.Z deposition. Interestingly, SWC4 silencing does not affect H2A.Z deposition at the FLC locus nor expression of this gene, a master regulator of flowering previously shown to be controlled by SWR1-C. Importantly, we find that SWC4 recognizes specific AT-rich DNA elements in the chromatin regions of target genes and that SWC4 silencing impairs SWRI-C binding at FT. Collectively, our data suggest that SWC4 regulates plant growth and development by aiding SWR1-C recruitment and modulating H2A.Z deposition.

关键词： Arabidopsis SWC4 chromatin SWR1 complex H2A.Z deposition flowering time

A New Analysis of an Implicit Mimetic Scheme for the Heat Equation

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Journal of Applied Mathematics and Physics 2023年第3期11卷 841-857页

作者： Mariela Castillo Nava juan manuel guevara-Jordan Universidad Metropolitana Caracas Venezuela Universidad Central de Venezuela Caracas Venezuela

A mimetic finite difference scheme for the transient heat equation under Robin’s conditions is presented. The scheme uses second order gradient and divergence mimetic operators, on a staggered grid, to approximate the space derivatives. The temporal derivative is replaced by a first order backward difference approximation to obtain an implicit formulation. The resulting scheme contains nonstandard finite difference stencils. An original convergence analysis by the matrix’s method shows that the proposed scheme is unconditionally stable. A comparative study against standard finite difference schemes, based on central difference or first order one side approximations, reveals the advantages of our scheme without being its implementation more expensive or difficult to achieve.

关键词： Mimetic Finite Difference Robin’s Condition Implicit Stable Transient Heat

Determining the need for a thoracoscopic approach to treat a giant hiatal hernia when abdominal access is poor

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World Journal of gastrointestinal Surgery 2023年第12期15卷 2739-2746页

作者： Francisco Javier Pérez Lara Rogelio Zubizarreta Jimenez Tatiana Prieto-Puga Arjona Pilar gutierrez Delgado juan manuel Hernández Carmona Jose manuel Hernández gonzalez Maria Pitarch Martinez Department of Surgery Hopital de AntequeraAntequera 29200Spain DOXA MicrofluidicsRincon de la Victoria 29730Spain Department of Surgery HRU Carlos HayaUnidad Cirugia Hepatobiliopancreat&TrasplantesMalaga 29200Spain

BACKgROUND giant hernias present a significant challenge for digestive *** approach taken(laparoscopic vs thoracoscopic)depends largely on the preferences and skills of each surgeon,although in most cases today the laparoscopic approach is *** To determine whether patients presenting inadequate laparoscopic access to the intrathoracic hernial sac obtain poorer postoperative results than those with no such problem,in order to assess the need for a thoracoscopic *** For the retrospective series of patients treated in our hospital for hiatal hernia(n=112),we calculated the laparoscopic field of view and the working area accessible to surgical instruments,by means of preoperative imaging tests,to assess the likely outcome for cases inaccessible to *** Patients with giant hiatal hernias for whom a preoperative calculation suggested that the laparoscopic route would not access all areas of the intrathoracic sac presented higher rates of perioperative complications and recurrence during follow-up than those for whom laparoscopy was *** difference was statistically ***,the insertion of mesh did not improve results for the non-accessible *** For patients with giant hiatal hernias,it is essential to conduct a preoperative evaluation of the angle of vision and the working area for *** parts of the intrathoracic sac are inaccessible laparoscopically,the thoracoscopic approach should be considered.

关键词： Hiatal hernia Abdominal surgery Laparoscopy Thoracoscopy surgery

Contralateral trapezius transfer to treat scapular winging: A case report and review of literature

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World Journal of Orthopedics 2019年第1期10卷 33-44页

作者： juan José gil-álvarez Pablo garcía-Parra manuel Anaya-Rojas María del Pilar Martínez-Fuentes Department of Orthopedics and Traumatology Hospital Universitario Virgen del Rocío Department of Rehabilitation Hospital Universitario Virgen del Rocío

BACKgROUND No dynamic technique, such as tendon transfer, has been described for scapular winging due to levator scapulae or rhomboid major and minor palsies resulting from an isolated dorsal scapular nerve injury. Thus, we evaluated how the contralateral trapezius compound osteomuscular flap transfer would work in stabilizing lateral scapular winging, and the case is reported here. A literature review was also conducted, and articles relevant to the case are *** SUMMARY A 37-year-old male patient who had sustained an isolated dorsal scapular nerve injury underwent reconstructive surgery using the contralateral trapezius compound osteomuscular flap transfer technique to treat scapular winging and the consequent pain, and to restore function from the shoulder impairment. As a result, the involved shoulder showed an improved Constant-Murley score, from19.5% to 81.88%.CONCLUSION Contralateral trapezius osteomuscular flap transfer succeeded in stabilizing scapular winging in this case, improving shoulder function and affording pain relief.

关键词： Trapezoid muscle Osteomuscular flap Scapular winging Rhomboid muscles Nerve paralysis Dorsal scapular nerve Case report

Sustainability Assessment of Wastewater Systems: An Environmental and Economic Approach

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Journal of Environmental Protection 2019年第2期10卷 241-259页

作者： Alejandro Padilla-Rivera juan manuel Morgan-Sagastume Leonor Patricia güereca-Hernández Instituto de Ingeniería Universidad Nacional Autónoma de México Coyoacán Mexico City Mexico

To address current challenges regarding sustainable development of wastewater treatment and provide scientific support in decision procedures towards sustainable solutions, new approaches, frameworks and methodologies about different possible solutions and their potential sustainability implications are needed. One way to facilitate sustainability assessment of wastewater is Life Cycle Assessment (LCA) methodology;however, it fails to map the full scope of wastewater impacts. This paper presents a framework to evaluate the performance of Wastewater Treatment Facilities (WWTF) taking into consideration various factors for insuring environmental sustainability. A total of nine indicators, seven environmental and two economic related to four wastewater treatment facilities, were assessed. Apart from evaluating the sustainability, this study also discussed the link of life cycle approach and social aspects of wastewater. The results show that for the environmental dimension using LCA provides information on different types of environmental activities and different impact categories. LCA can thus be used to quantify and compare the multiple types of impacts caused by one type of use or emission, as well as the various resource uses or emissions that contribute to one type of impacts. For the economic dimension, there is still a need for consistent and robust indicators and methods. The empirical results suggest that the environmental sustainability framework can be used in the first phase of the decision procedure that leads to a strategic choice for sustainable resource recovery from wastewater in developing countries. This motives researchers and decision-makers to consider the whole picture, and not just individual aspects, when considering different futures scenarios.

关键词： Environmental life Cycle Assessment Wastewater Treatment Economic Costs

Achieving the best bowel preparation for colonoscopy

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World Journal of gastroenterology 2014年第47期20卷 17709-17726页

作者： Adolfo Parra-Blanco Alex Ruiz manuel Alvarez-Lobos Ana Amorós juan Cristóbal gana Patricio Ibáez Akiko Ono Takahiro Fujii Department of gastroenterology Escuela de MedicinaPontificia Universidad Católica de ChileSantiago 833-0024Chile Department of gastroenterology Hospital Universitario de la Candelaria38916 Santa Cruz de TenerifeSpain gastroenterology and Nutrition Unit Division of PediatricsEscuela de MedicinaPontificia Universidad Católica de ChileSantiago 833-0024Chile Department of gastroenterology Hospital Universitario Virgen de la Arrixaca30001 MurciaSpain TF Clinic Tokyo 197-0804Japan

Bowel preparation is a core issue in colonoscopy,as it is closely related to the quality of the *** often find that bowel preparation is the most unpleasant part of the *** is widely accepted that the quality of cleansing must be excellent to facilitate detecting neoplastic *** spite of its importance and potential implications,until recently,bowel preparation has not been the subject of much *** most commonly used agents are high-volume polyethylene glycol(PEg)electrolyte solution and sodium *** has been some confusion,even in published meta-analyses,regarding which of the two agents provides better *** is clear now that both PEg and sodium phosphate are effectivewhen administered with proper ***,the timing of administration is recognized as one of the central factors to the quality of *** bowel preparation agent should be administered,at least in part,a few hours in advance of the *** low volume agents are available,and either new or modified schedules with PEg that usually improve *** adjuvants can also be used to reduce the volume of PEg,or to improve the efficacy of other *** factors apart from the choice of agent can improve the quality of bowel *** instance,the effect of diet before colonoscopy has not been completely clarified,but an exclusively liquid diet is probably not required,and a low-fiber diet may be preferable because it improves patient satisfaction and the quality of the *** patients,such as diabetics and persons with heart or kidney disease,require modified procedures and certain *** preparation for pediatric patients is also reviewed *** such cases,PEg remains the most commonly used *** detecting neoplasia is not the main objective with these patients,less intensive preparation may *** considerations must be made for patients with inflammatory bowel disease,including

关键词： Colonoscopy Optimal preparation Polyethylene glycol Sodium phosphate Special patients Timing

Consolidation of Ancient Raw Materials Using a Reversible, Elastic, Soft Polymer

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Advances in Materials Physics and Chemistry 2012年第1期2卷 37-42页

作者： juan manuel Navarrete gustavo Leonardo Martínez Faculty of Chemistry Inorganic and Nuclear Chemistry Department National University of Mexico Mexico City Mexico National Coordination to Restore the Cultural Inheritance National Institute of Anthropology and History Mexico City Mexico

Aging of ancient raw materials usually finish with disintegration, which starts on surface of walls to progress toward the inside mass of a huge variety of mineral compounds. This is particularly harmful when antique buildings keep mural paintings, which suffers destruction before the wall itself. Same case appears on sculptures and monuments, whose surfaces are often attacked by living organisms which start a deterioration process previous to complete disintegration. The main factor to produce these unwanted effects is humidity, either rain for materials exposed to open air, or underground humidity going up by capillarity of minerals, in this case represented by porosity of associated salts forming the material. This paper describes a method to measure easily the relative porosity of diverse raw materials at laboratory level, by using a radioactive labeled solution, and also a procedure to reduce their porosity of those minerals. The efficiency of this procedure is measured in the same way, and so the results obtained at laboratory level have encouraged its use at real scale, where it has been quite successful for a number of materials in a limited span of five years.

关键词： Consolidation Preservation Humidity Ancient Materials

Site Characterization Index for Continuous Power Quality Monitoring Based on Higher-order Statistics

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 222-231页

作者： Olivia Florencias-Oliveros juan-José gonzález-de-la-Rosa Jose-María Sierra-Fernández Agustín Agüera-Pérez manuel-Jesús Espinosa-gavira José-Carlos Palomares-Salas Department of Automation Engineering ElectronicsArchitecture and Computers NetworksResearch Group TIC168Higher Polytechnic SchoolUniversity of CádizAlgeciras 11202Spain

The high penetration of distributed generation(Dg)has set up a challenge for energy management and consequently for the monitoring and assessment of power quality(PQ).Besides,there are new types of disturbances owing to the uncontrolled connections of non-linear *** stochastic behaviour triggers the need for new holistic indicators which also deal with big data of PQ in terms of compression and scalability so as to extract the useful information regarding different network states and the prevailing PQ disturbances for future risk assessment and energy management *** and continuous monitoring would guarantee the report to claim for damages and to assess the risk of PQ *** this context,we propose a measurement method that postulates the use of two-dimensional(2D)diagrams based on higher-order statistics(HOSs)and a previous voltage quality index that assesses the voltage supply waveform in a continous monitoring *** suitable for both PQ and reliability applications,the results conclude that the inclusion of HOS measurements in the industrial metrological reports helps characterize the deviations of the voltage supply waveform,extracting the individual customers’pattern fingerprint,and compressing the data from both time and spatial *** method allows a continuous and robust performance needed in the Sg ***,the method can be used by an average consumer as a probabilistic method to assess the risk of PQ deviations in site characterization.

关键词： Continuous statistical monitoring big data data compression higher-order statistics(HOSs) power quality(PQ)