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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

Vertical Displacement Measurement in a Slow-Moving Sinkhole Using BOTDA

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Photonic Sensors 2024年第1期14卷 23-39页

作者： Pascual SEVILLANO Javier PRECIADO-GARBAYO Jorge SEVIL Francisco GUTIERREZ juan JmartinEZ Sonia martin-LOPEZ Miguel GONZALEZ-HERRAEZ Aragon Institute of Engineering Research(I3A) Universidad de ZaragozaZaragoza 50018Spain Electronic Enginering and Communicaton Dpartment EINAUniversidad de ZaragzaZaragza 50018Spain Aragon Photonics Labs. Zaragoza 50009Spain Department of Earth Sciences Universidad de ZaragozaZaragoza 50009Spain Department of Electronics Escuela Politecnica SuperiorUniversidad de AlcalaMadrid 28805Spain

The effectiveness of monitoring and early-warning systems for ground deformation phenomena,such as sinkholes,depends on their ability to accurately resolve the ongoing ground displacement and detect the subtle deformation preceding catastrophic *** sinkholes with a slow subsidence rate and diffuse edges pose a significant challenge for subsidence monitoring due to the low deformation rates and limited lateral strain *** this work,we satisfactorily illustrate the practicality of the Brillouin optical time domain analysis(BOTDA)to measure the spatial-temporal patterns of the vertical displacement in such challenging slow-moving sagging *** assess the performance of the approach,we compare the strain recorded by the distributed optical fiber sensor with the vertical displacement measured by high-precision *** results show a good spatial correlation with the ability to identify the maximum subsidence *** is also a good temporal correlation with the detection of an acceleration phase in the subsidence associated with a flood event.

关键词： Distributed fiber optic sensing(DFOS) vertical displacement measurement slow subsidence rate sinkhole hazard early-warning system

Microbial interactions within Chinese traditional medicinal plants

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Chinese Herbal Medicines 2024年第2期16卷 169-171页

作者： juan Chen Luping Qin Key Laboratory of Bioactive Substances and Resource Utilization of Chinese Herbal Medicine Ministry of EducationInstitute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100193China School of Pharmaceutical Sciences Zhejiang Chinese Medical UniversityHangzhou 310053China

Plants harbor diverse microbes(including bacteria,fungi,archaea,protists,and viruses)both inside and outside their tissues,so called the plant-associated *** of research have demonstrated the importance of plant microbiome in promoting the productivity and health of the plant in natural environment because of their essential functions in improving plant nutrition and plant resistance to biotic and abiotic stresses(Trivedi,Leach,Tringe,Sa,&Singh,2020).Thus,a plant can be regarded as a holobiont comprising the host plant and the associated microbiota(Hassani,Durán,&Hacquard,2018).Within the plant microbiota,mutualistic fungal and bacterial symbionts(*** fungi and Rhizobia)are striking examples of microorganisms playing crucial roles in nutrient acquisition(martin&van der Heijden,2024)and non-symbitic plant growth-promoting rhizobacteria or fungi(PGPR or PGPF)also have drawn interest due to their ability to improve soil properties and confer stress tolerance in plants(Upadhyay et al.,2023).

关键词： mutual striking outside

Assessment of pressure drop in conical spouted beds of biomass by artificial neural networks and comparison with empirical correlations

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Particuology 2022年第11期70卷 1-9页

作者： juan F.Saldarriag Yuby Cruz Idoi Estiati Mikel Tellabide martin Olazar Department of Civil and Environmental Engineering Universidad de los AndesCarrera 1Este#19A-40BogotaColombia Department of Chemical Engineering University of the Basque CountryBarrio Sarriena s/nLeioaSpain

Pressure drop is an essential parameter in the operation of conical spouted beds(CSB)and depends on its geometric factors and materials *** materials,like biomass,are complex to treat and,unlike other gas–solid contact methods,CSB turn out to be a suitable technology for their *** neural networks were used in this study for the prediction of operating and peak pressure drops,and their performance has been compared with that of empirical correlations reported in the ***,a multi-layer perceptron network with backward propagation was used due to its ability to model non-linear multivariate *** fitting of the experimental data of both operating and peak pressure drop was significantly better than those reported in the literature,specifically in the case of the peak pressure drop,with R^(2) being ***,artificial neural networks have been proven suitable for the prediction of pressure drop in CSB.

关键词： Pressure drop Artificial neural networks Biomass Spouted bed

Topological Minors in Bipartite Graphs

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Acta Mathematica Sinica,English Series 2011年第11期27卷 2085-2100页

作者： Camino BALBUENA martin CERA Pedro GARCIA-VAZQUEZ juan Carlos VALENZUELA Departament de Matematica Aplicada III Universitat Politecnica de Catalunya C/ Jordi Girona 1-3 （ Edifici C2 Despatx 302） 08034 Barcelona Spain Departamento de Matemdtica Aplicada I Universidad de SeviUa EUIT Agrlcola Ctra. Utrera Kin. 1 41013 Sevilla Spain Departamento de Matemdtica Aplicada I Universidad de Sevilla ETS Arquitectura Avda. Reina Mercedes 2 41012 Sevilla Spain Departamento de Matemdticas Universidad de Cddiz EPS Algeciras Avda. Ramdn Puyol s/n 11202 Algeciras Spain

For a bipartite graph G on m and n vertices, respectively, in its vertices classes, and for integers s andt such that 2≤ s ≤ t, 0≤ m-s ≤ n-t, andre＋n≤ 2s＋t-1, we prove that if G has at least mn- （2（m - s）＋ n - t） edges then it contains a subdivision of the complete bipartite K（s,t） with s vertices in the m-class and t vertices in the n-class. Furthermore, we characterize the corresponding extremal bipartite graphs with mn- （2（m - s）＋ n - t ＋ 1） edges for this topological Turan type problem.

关键词： Bipartite graphs extremal graph theory topological minor

HEART RATE VARIABILITY DURING HIGH-INTENSITY EXERCISE

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Journal of Systems Science & Complexity 2013年第1期26卷 104-116页

作者： SARMIENTO Samuel GARCIA-MANSO juan Manuel martin-GONZALEZ juan Manuel VA-AMONDE Diana CALDERóN Javier DA SILVA-GRIGOLETTO Marzo Edir Department of Physical Education University of Las Palmas de Gran Canaria Spain. Physics Department University of Las Palmas de Gran Canaria Spain. Department of Morphological Sciences School of Medicine University of Cdrdoba Spain. Physical Activity Sciences Faculty Polytechnic University of Madrid Spain. Andalusian Centre of Sports Medicine Cdrdoba Spain.

The aim of this paper is to describe and analyse the behaviour of heart rate variability(HRV)during constant-load,high-intensity exercise using a time frequency analysis(Wavelet Transform).Eleven elite cyclists took part in the study(age:18.6±3.0 years;VO_(2max):4.88±0.61 litres·min^(-1)).Initially,all subjects performed an incremental cycloergometer test to determine load power in a constant load-test(379.55±36.02 W;89.0%).HRV declined dramatically from the start of testing(p<0.05).The behaviour of power spectral density within the LF band mirrored that of total energy,recording a significant decrease from the outset LF peaks fell rapidly thereafter,remaining stable until the end of the ***-VHF fell sharply in the first 20 to 30 *** relative weighting(%) of HF-VHF was inverted with the onset of fatigue,[1.6%at the start,7.1(p<0.05) at the end of the first phase,and 43.1%(p<0.05) at the end of the test].HF-VHF_(peak) displayed three phases:a moderate initial increase,followed by a slight fall,thereafter increasing to the end of the *** LF/HF-VHF ratio increased at the start,later falling progressively until the end of the first phase and remaining around minimal values until the end of the test.

关键词： Cycling heart rate variability wavelet.

The role of associating liver partition and portal vein ligation for staged hepatectomy in the management of patients with colorectal liver metastasis

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Hepatobiliary Surgery and Nutrition 2020年第6期9卷 694-704页

作者： juan Glinka Victoria Ardiles juan Pekolj Eduardo de Santibañes martin de Santibañes Department of General Surgery Hepato-Bilio-Pancreatic&Liver Transplantation Unit Hospital Italiano de Buenos AiresBuenosAiresArgentina

Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)approach emerged as a promising surgical strategy for rapid and large hypertrophy of the future liver remnant(FLR)when a major liver resection is *** liver metastasis(CRLM)is their main ***,the promising results published so far,are very difficult to interpret since they usually focus on the technique and not on the underlying ***,they are usually made up of complex populations,which received different chemotherapy schemes,with the ALPPS technical variations implemented over time and without consistent long-term follow-up results as ***,its role in CRLM should be analyzed as carefully as possible to indicate and select the best candidates who will benefit the most from this *** conducted a computerized search using PubMed and Google Scholar for reports published so far,using mesh headings and keywords related to the ALPPS and CRLM.

关键词： Liver resection associating liver partition and portal vein ligation for staged hepatectomy(ALPPS) colorectal cancer metastasis liver regeneration

Experimental hybridization and reproductive isolation between two sympatric species of tephritid fruit flies in the Anastrepha fraterculus species group

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Insect Science 2018年第6期25卷 1045-1055页

作者： juan Rull Eduardo Tadeo Rodrigo Lasa Christian L.Rodriguez Alma Altuzar-Molina martin Aluja PROIMI Biotecnologia-OONICET LIEMEN-Division Control Biologico de PlagasTucumanArgentina Red de Manejo Biorracional de Plagas y Vectores Instituto de EcologiaA.C.XalapaVeracruzMexico

Among tephritid fruit flies,hybridization has been found to produce local adaptation and speciation,and in the case of pest species,induce behavioral and ecological alterations that can adversely impact efficient pest *** species group within Anastrepha (Diptera:Tephritidae),is a rapidly radiating aggregate,which includes cryptic species complexes,numerous sister species,and several pest species. Molecular studies have highlighted the possibility of introgression between *** and *** isolation has been studied among morphotypes of the A. fraterculus species complex as a tool for species *** we examined the exis- tence and strength of prezygotic and postzygotic isolation between sympatric populations of two closely related species within the highly derivedfraterculus group (*** and ***),coexisting in *** adults of both species showed a strong tendency for assortative mating,a small proportion of hybrid pairings in both directions were *** also observed asymmetric postzygotic isolation,with one hybrid cross displaying a strong reduction in fecundity and F1 egg *** was greater for the progeny of homotypic and hybrid crosses in the maternal *** was a marked female biased sex ratio distortion for both F1 hybrid *** between *** and *** in nature may be difficult but possible;these two species display stronger reproductive isolation than all pairs of species previously examined in the *** species *** postzygotie isolation is suggestive of Wolbachia mediated cytoplasmic incompatibilities that may be exploited in area-wide pest management.

关键词： Anastrephafraterculus Anastrepha obliqua Haldane's rule introgression prezygotic isolation postzygotic isolation

Small-signal Model for Dual-active-bridge Converter Considering Total Elimination of Reactive Current

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 450-458页

作者： juan Ramon Rodriguez-Rodriguez Nadia Maria Salgado-Herrera Jacinto Torres-Jimenez Nestor Gonzalez-Cabrera David Granados-Lieberman martin Valtierra-Rodriguez the Universidad Nacional Autonoma de Mexico Facultad de IngenieriaDepto.Energia Electri-ca.Av.Universidad 3000Col.UNAM CUCoyoacanCDMXMexico the Instituto de Energias Renovables Universidad Nacional Autonoma de MexicoPriv.Xochicalco s/nCol.Centro.TemixcoMorelosMexico the Instituto Tec-nologico Superior de Irapuato Carretera Irapuato-Silao km 12.5.IrapuatoGuanajuatoMexico the Universidad Autonoma de Queretaro Campus San Juan del RioRio Moctezuma 249San Juan del RioQueretaroMexico

Emerging technologies such as electric vehicles,solid-state transformers,and DC transformers are implemented using the closed-loop bi-directional dual-active-bridge(DAB)*** this context,it is necessary to have average models that provide an efficient way of tuning the proportional integral(PI)compensator parameters for large-and small-signal *** present a novel small-signal model(SSM)for DAB converter with a single closed-loop PI controller and the total elimination of reactive current(IQ=0).The method applies a modulation technique for IQ=0 and introduces a composite function in the controller while reducing the original nonlinear switching model,which allows to decrease the order of the transfer function and analyze the closed-loop *** proposed SSM is analyzed using different response time,load,and DC voltage *** simulation and experimental results demonstrate the ease of implementation and effectiveness of the proposed model with respect to other SSM techniques.

关键词： Small-signal model(SSM) dual-active-bridge(DAB)converter reactive current elimination proportional integral(PI)control