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Free-electron interactions with van der Waals heterostructures: a source of focused X-ray radiation

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Light(Science & Applications) 2023年第7期12卷 1370-1380页

作者： Xihang Shi Yaniv Kurman Michael Shentcis Liang Jie Wong F.javier garc.a de Abajo ldo Kaminero Solid State Institute and Faculty of Electrical and Computer Engineering Technion-Israel Institute of TechnologyHaifa 32000Israel School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798Singapore ICFO-Institut de Ciencies Fotoniques The Barcelona Institute of Science and TechnologyCastelldefels 08860Spain iCREA-lnstitucio Catalana de Recerca i Estudis Avangats Passeig Lluis Companys23Barcelona08010Spain

The science and technology of X-ray optics have come far,enabling the focusing of X-rays for applications in highresolution X-ray spectroscopy,imaging,and *** spite of this,many forms of tailoring waves that had substantial impact on applications in the optical regime have remained out of reach in the X-ray *** disparity fundamentally arises from the tendency of refractive indices of all materials to approach unity at high frequencies,making X-ray-optical components such as lenses and mirrors much harder to create and often less ***,we propose a new concept for X-ray focusing based on inducing a curved wavefront into the X-ray generation process,resulting in the intrinsic focusing of X-ray *** concept can be seen as effectively integrating the optics to be part of the emission mechanism,thus bypassing the effciency limits imposed by X-ray optical components,enabling the creation of nanobeams with nanoscale focal spot sizes and micrometer-scale focal ***,we implement this concept by designing aperiodic vdw heterostructures that shape X-rays when driven by free *** parameters of the focused hotspot,such as lateral size and focal depth,are tunable as a function of an interlayer spacing chirp and electron *** forward,ongoing advances in the creation of many-layer vdw heterostructures open unprecedented horizons of focusing and arbitrary shaping of X-ray nanobeams.

关键词： optics integrating arbitrary

Long-term outcomes after stenting as a"bridge to surgery"for the management of acute obstruction secondary tocolorectal cancer

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World Journal of Gastrointestinal Oncology 2016年第1期8卷 105-112页

作者： javier suárez javier jimenez-pérez department of general surgery coloproctology unitcomplejo hospitalario de navarra31008 PamplonaSpain department of gastroenterology endoscopy unithospital de la ribera46600 AlziraSpain

Obstructive symptoms are present in 8% of cases at the time of initial diagnosis in cases of colorectal cancer. Emergency surgery has been classically considered the treatment of choice in these patients. However, in the majority of studies, emergency colorectal surgery is burdened with higher morbidity and mortality rates than elective surgery, and many patients require temporal colostomy which deteriorates their quality of life and becomes permanent in 10%-40% of cases. The aim of stenting by-pass to surgery is to transform emergency surgery into elective surgery in order to improve surgical results, obtain an accurate tumoral staging and detection of synchronous lesions, stabilization of comorbidities and performance of laparoscopic surgery. Immediate results were more favourable in patients who were stented concerning primary anastomosis, permanent stoma, wound infection and overall morbidity, having the higher surgical risk patients the greater benefit. However, some findings laid out the possible implication of stenting in long-term results of oncologic treatment. Perforation after stenting is related to tumoral recurrence. In studies with perforation rates above 8%, higher recurrences rates in young patients and lower disease free survival have been shown. On the other hand, after stenting the number of removed lymph nodes in the surgical specimen is larger, patients can receive adjuvant chemotherapy earlier and in a greater percentage and the number of patients who can be surgically treated with laparoscopic surgery is larger. Finally, there are no consistent studies able to demonstrate that one strategy is superior to the other in terms of oncologic benefits. At present, it would seem wise to assume a higher initial complication rate in young patients without relevant comorbidities and to accept the risk of local recurrence in old patients(> 70 years) or with high surgical risk(ASA Ⅲ/Ⅳ).

关键词： Self-expanding metallic stent Colorectalcancer Obstructive colorectal cancer Colorectal cancerchemotherapy Colorectal cancer surgery

Holographic Duals of Quark Gluon Plasmas with Unquenched Flavors

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Communications in Theoretical Physics 2012年第3期57卷 364-386页

作者： Francesco Bigazzi Aldo Cotrone javier Mas Daniel Mayerson javier Tarrio Dipartimento di Fisica e Astronomia Universita' di Firenze Via G.Sansone 1 I-50019 Sesto Fiorentino (Firenze)Italyand INFNSezione di PisaLargo B.Pontecorvo356127 PisaItaly Dipartimento di Fisica Universita' di Torino and INFN Sezione di Torino Via P.Giuria 1 I-10125 TorinoItaly Departamento de F' sica de Part' culas Universidade de Santiago de Compostela and Instituto Galego de F' sica de Altas Enerx' as (IGFAE) E-15782 Santiago de CompostelaSpain Institute for Theoretical Physics University of AmsterdamScience Park 904Postbus 944851090 GL AmsterdamThe Netherlands Institute for Theoretical Physics Universiteit Utrecht3584 CEUtrechtThe Netherlands

We review the construction of gravitational solutions holographically dual to N=1 quiver gauge theories with dynamical flavor *** focus on the D3-D7 construction and consider the finite temperature,finite quark chemical potential case where there is a charged black hole in the dual *** physical outputs of the model include its thermodynamics (with susceptibilities) and general hydrodynamic properties.

关键词： AdS/CFT correspondence quark-gluon plasma flavor physics finite baryon density

Sex and habitat differences in size and coloration of an amphibian’s poison glands match differential predator pressures

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Integrative Zoology 2022年第5期17卷 764-776页

作者： Francisco javier ZAMORA-CAMACHO Department of Phisical Chemical and Natural SystemsPablo de Olavide UniversitySevilleSpain Department of Biodiversity Ecology and EvolutionComplutense University of MadridMadridSpain

Chemical defenses are frequently accompanied by salient color patterns actively avoided by predators,a phe-nomenon referred to as ***,the production of both chemical defenses and pigments is costly,and is thus expected to be reduced under mild predator *** this work,I compared the size and coloration of parotoid glands(2 dorsal,external swollen structures that secrete toxins in toads)of male and female Epidalea calamita toads from agrosystems and from pine groves.I also quantiﬁed the predator attacks received by plas-ticine toad models,whose“parotoid glands”differed in size and color conspicuousness,exposed in each *** avoided models with large and conspicuous parotoid glands,but models in agrosystems were more of-ten *** actual toads,agrosystem and male individuals had larger parotoid glands,presumably implying greater production of chemical defenses than in pine grove and female conspeciﬁ***ﬁndings are aligned with previous research suggesting that both agrosystem toads and males in this system are subjected to a more intense predator *** between parotoid gland and dorsum coloration was greater in agrosys-tem toads.A marked internal pattern could function as an aposematic signal,which could counteract increased predator pressure.

关键词： anuran agrosystem aposematism Epidalea calamita plasticine model

Interindividual Age-Independent Differences in Human CX43 Impact Ventricular Arrhythmic Risk

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Research 2024年第3期6卷 417-432页

作者： Laura garc.a-Mendívil María Pérez-Zabalza Antoni Oliver-Gelabert JoséMaría Vallejo-Gil javier Fañanás-Mastral Manuel Vázquez-Sancho javier AndréBellido-Morales Alexánder Sebastián Vaca-Núñez Carlos Ballester-Cuenca Emiliano Diez Laura Ordovás Esther Pueyo Biomedical Signal Interpretation and Computational Simulation group(BSICoS) Aragón Institute of Engineering ResearchUniversity of ZaragozaZaragoza 50018Spain BSICoS Instituto de Investigación Sanitaria Aragón(IISA)Zaragoza 50018Spain Centro Universitario de la Defensa(CUD) Zaragoza 50090Spain. Department of Cardiovascular Surgery University Hospital Miguel ServetZaragoza 50009Spain. Institute of Experimental Medicine and Biology of Cuyo(IMBECU) CONICETMendoza 5500Argentina. Fundación Agencia Aragonesa para la Investigación y el Desarrollo(ARAID) Zaragoza 50018Spain. Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)Zaragoza 50018Spain.

Connexin 43 (CX43) is one of the major components of gap junctions, the structures responsible for the intercellular communication and transmission of the electrical impulse in the left ventricle. There is limited information on the histological changes of CX43 with age and their effect on electrophysiology, especially in humans. Here, we analyzed left ventricular biopsies from living donors starting at midlife to characterize age-related CX43 remodeling. We assessed its quantity, degree of lateralization, and spatial heterogeneity together with fibrotic deposition. We observed no significant age-related remodeling of CX43. Only spatial heterogeneity increased slightly with age, and this increase was better explained by biological age than by chronological age. Importantly, we found that CX43 features varied considerably among individuals in our population with no relevant relationship to age or fibrosis content, in contrast to animal species. We used our experimental results to feed computational models of human ventricular electrophysiology and to assess the effects of interindividual differences in specific features of CX43 and fibrosis on conduction velocity, action potential duration, and arrhythmogenicity. We found that larger amounts of fibrosis were associated with the highest arrhythmic risk, with this risk being increased when fibrosis deposition was combined with a reduction in CX43 amount and/or with an increase in CX43 spatial heterogeneity. These mechanisms underlying high arrhythmic risk in some individuals were not associated with age in our study population. In conclusion, our data rule out CX43 remodeling as an age-related arrhythmic substrate in the population beyond midlife, but highlight its potential as a proarrhythmic factor at the individual level, especially when combined with increased fibrosis.

关键词： CX43 rhythm Independent

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World Journal of Gastroenterology 2013年第30期19卷 4877-4886页

作者： María Gómez-garc.a Maria José Cabello-Tapia Antonio Damián Sánchez-Capilla javier De Teresa-Galván Eduardo Redondo-Cerezo Inflammatory Bowel Disease Unit Department of GastroenterologyUniversity Hospital Virgen de Las Nieves18014 GranadaSpain Department of Gastroenterology University Hospital Virgen de Las Nieves18014 GranadaSpain Endoscopy Unit Department of GastroenterologyUniversity Hospital Virgen de Las Nieves18014 GranadaSpain

AIM:To investigate the incidence of neoplasms in inflammatory bowel disease(IBD)patients and the potential causative role of ***:We performed an observational descriptive study comparing the incidence of malignancies in IBD patients treated with thiopurines and patients not treated with these *** included 812 patients which were divided in two groups depending on whether they have received thiopurines or *** have studied basal characteristics of both groups(age when the disease was diagnosed,sex,type of IBD,etc.)and treatments received(Azathioprine,mercaptopurine,infliximab,adalimumab or other immunomodulators),as well as neoplasms *** analysis was performed with the student t test,χ 2 test or Wilcoxon exact test as appropriate.A logistic regression analysis was performed as multivariate *** significance was establish at P values of less than 0.05,and 95%CI were used for the odds ***:Among 812 patients included,429(52.83%)have received thiopurines:79.5% azathioprine,14% mercaptopurine and 6.5% both drugs.44.76% of patients treated with thiopurines and 46,48% of patients who did not receive this treatment were women(P > 0.05).The proportion of ulcerative colitis patients treated with thiopurines was 30.3% compare to 66.67% of patients not treated(P < 0.001).Mean azathioprine dose was 123.79 ± 36.5 mg/d(range:50-250 mg/d),mean usage time was 72.16 ± 55.7 mo(range:1-300 mo)and the accumulated dose along this time was 274.32 ± 233.5 g(1.5-1350 g).With respect to mercaptopurine,mean dose was 74.7 ± 23.9 mg/d(range:25-150 mg/d),mean usage time of 23.37 ± 27.6 mo(range:1-118 mo),and the accumulated dose along this time was 52.2 ± 63.5 g(range:1.5-243 g).Thiopurine S-methyltransferase activity was tested in 66% of patients treated with thiopurines,among which 98.2% had an intermediate or high *** the patients treated with thiopurines,27.27%(112 patients)and 11.66%(50 patients)received treatment

关键词： Malignancy Neoplasm Inflammatory bowel disease Crohn’s disease Ulcerative colitis Thiopurines Azathioprine Mercaptopurine

Integrating time progression in ecoimmunology studies: beyond immune response intensity

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Current Zoology 2019年第2期65卷 205-212页

作者： Francisco javier ZAMORA-CAMACHO Department of Biological Sciences Dartmouth College Hanover New Hampshire USA Department of Biogeography and Global Change Museo Nacional de Ciencias Naturales (MNCN) Spanish National Research Council (CSIC) Madrid Spain

Habitat alterations in agroecosystems may damage amphibian immune capacity. As agroecosystem extension is increasing worldwide, broader-context knowledge on the effects of agroecosystem stressful conditions on amphibian immune capacity is crucial for understanding and management of amphibian global declines. However, most studies on ecoimmunology assume synchronal amonggroup immune-response peaks, and focus on immune response after standardized time lapses, neglecting its progress!on. Herein, I compared inflamatory response short-term progression of agro ecosystem and n atural-habitat female and male n atterjack toads Epi da lea calamita, by measuri ng swelling response, once per hour, 6 h following an artificial immune challenge with innocuous antigen phytohemagglutinin. I also compared maximum magnitude of swelling response, irrespective of the moment when it was reached. Habitat differences arose only 3 h after challenge, when naturalhabitat toads showed greater swelling response. Maximum magnitude of swelling response was similar in toads from both habitats. However, agroecosystem toads showed a delayed swelling response as compared with natural-habitat conspecifics, probably as a consequenee of agroecosystem stressful conditions. Such a delay suggests a weaker immune capacity, and consequently impaired anti-pathogen performance. Regarding sex, swelling response magnitude did not differ between males and females. Female swelling response peaked earlier, but that of males was more sustai ned in time, which con tradicts general across-taxa fin dings that males show impaired immune response. Interestingly, results suggest that measuring swelling response only after some standardized period following stimulation may be a simplistic approach and produce unrealistic results. Consequently, studies on ecoimmunology should implement swelling response progression in order to produce unbiased science.

关键词： agroecosystem amphibian immunocompetence natural habitat immune response progressi on

Quantum-mechanical effects in photoluminescence from thin crystalline gold films

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Light(Science & Applications) 2024年第4期13卷 783-794页

作者： Alan R.Bowman Alvaro Rodríguez Echarri Fatemeh Kiani Fadil Iyikanat Ted V.Tsoulos Joel D.Cox Ravishankar Sundararaman F.javier garc.a de Abajo Giulia Tagliabue Laboratory of Nanoscience for Energy Technologies(LNET) STIÉcole Polytechnique Fédérale de Lausanne(EPFL)LausanneSwitzerland ICFO–Institut de Ciencies Fotoniques The Barcelona Institute of Science and TechnologyCastelldefels(Barcelona)Spain. MBI–Max-Born-Institut BerlinGermany. POLIMA–Center for Polariton-driven Light–Matter Interactions University of Southern DenmarkOdense MDenmark. Danish Institute for Advanced Study University of Southern DenmarkOdense MDenmark. Department of Materials Science&Engineering Rensselaer Polytechnic InstituteTroyNYUSA. Department of Physics Applied Physicsand AstronomyRensselaer Polytechnic InstituteTroyNYUSA. ICREA–Institucio Catalana de Recerca i Estudis Avancats BarcelonaSpain

Luminescence constitutes a unique source of insight into hot carrier processes in metals,including those in plasmonic nanostructures used for sensing and energy ***,being weak in nature,metal luminescence remains poorly understood,its microscopic origin strongly debated,and its potential for unraveling nanoscale carrier dynamics largely ***,we reveal quantum-mechanical effects in the luminescence emanating from thin monocrystalline gold ***,we present experimental evidence,supported by first-principles simulations,to demonstrate its photoluminescence origin(i.e.,radiative emission from electron/hole recombination)when exciting in the interband *** model allows us to identify changes to the measured gold luminescence due to quantum-mechanical effects as the gold film thickness is ***,such effects are observable in the luminescence signal from flakes up to 40 nm in thickness,associated with the out-of-plane discreteness of the electronic band structure near the Fermi *** qualitatively reproduce the observations with first-principles modeling,thus establishing a unified description of luminescence in gold monocrystalline flakes and enabling its widespread application as a probe of carrier dynamics and light-matter interactions in this *** study paves the way for future explorations of hot carriers and charge-transfer dynamics in a multitude of material systems.

关键词： luminescence quantum crystalline

Involvement of ethylene receptors in the salt tolerance response of Cucurbita pepo

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Horticulture Research 2021年第1期8卷 1058-1071页

作者： Gustavo Cebrian Jessica Iglesias-Moya Alicia garc.a javier MartInez Jonathan Romero Jose javier Regalado Cecilia Martinez Juan Luis Valenzuela Manuel Jamilena Department of Biology and Geology Agri-food Campus of International Excellence(CeiA3)and Research Center CIAMBITALUniversity of Almeria04120 AlmeriaSpain

Abiotic stresses have a negative effect on crop production,affecting both vegetative and reproductive *** plays a relevant role in plant response to environmental stresses,but the specific contribution of ethylene biosynthesis and signalling components in the salt stress response differs between Arabidopsis and rice,the two most studied model *** this paper,we study the effect of three gain-of-function mutations affecting the ethylene receptors CpETR1B,CpETR1A,and CpETR2B of Cucurbita pepo on salt stress response during germination,seedling establishment,and subsequent vegetative growth of *** mutations all reduced ethylene sensitivity,but enhanced salt tolerance,during both germination and vegetative growth,demonstrating that the three ethylene receptors play a positive role in salt *** salt stress,etr1b,etr1a,and etr2b germinate earlier than WT,and the root and shoot growth rates of both seedlings and plants were less affected in mutant than in *** enhanced salt tolerance response of the etr2b plants was associated with a reduced accumulation of Na^(+)in shoots and leaves,as well as with a higher accumulation of compatible solutes,including proline and total carbohydrates,and antioxidant compounds,such as *** membrane monovalent cation transporters,including Na^(+)/H^(+)and K^(+)/H^(+)exchangers(NHXs),K^(+)efflux antiporters(KEAs),high-affinity K^(+)transporters(HKTs),and K^(+)uptake transporters(KUPs)were also highly upregulated by salt in etr2b in comparison with *** aggregate,these data indicate that the enhanced salt tolerance of the mutant is led by the induction of genes that exclude Na+in photosynthetic organs,while maintaining K^(+)/Na^(+)homoeostasis and osmotic *** the salt response of etr mutants occurs via the ethylene signalling pathway,our data show that ethylene is a negative regulator of salt tolerance during germination and vegetative ***,the higher upregulation

关键词： subsequent aggregate likely