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Pseudomelanosis duodeni associated with chronic renal failure 被引量:2
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作者 Marcia Henriques de Magalhes Costa Maria da Gloria Fernandes Pegado +4 位作者 Cleber Vargas Maria Elizabeth C Castro Kalil Madi Tiago Nunes Cyrla Zaltman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第12期1414-1416,共3页
Pseudomelanosis duodeni (PD) is a rare dark speckled appearance of the duodenum associated with gastrointestinal bleeding,hypertension,chronic heart failure,chronic renal failure and consumption of different drugs.We ... Pseudomelanosis duodeni (PD) is a rare dark speckled appearance of the duodenum associated with gastrointestinal bleeding,hypertension,chronic heart failure,chronic renal failure and consumption of different drugs.We report four cases of PD associated with chronic renal failure admitted to the gastroenterology outpatient unit due to epigastric pain,nausea,melena and progressive reduction of hemoglobin index.Gastroduodenal endoscopy revealed erosions in the esophagus and stomach,with no active bleeding at the moment.In addition,the duodenal mucosa presented marked signs of melanosis;later confirmed by histopathological study.Even though PD is usually regarded as a benign condition,its pathogenesis and clinical significance is yet to be defined. 展开更多
关键词 Pseudomelanosis duodeni Chronic renal fail-ure Diabetes mellitus Anti hypertensive drugs Gastro-duodenal endoscopy
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In-depth understanding of ionic liquid assisted perovskite film formation mechanism for two-step perovskite photovoltaics 被引量:1
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作者 Fei Wang Patrick Wai-Keung Fong +12 位作者 Zhiwei Ren Hai-Lun Xia Kang Zhou Kai Wang Jiajie Zhu Xiaoxi Huang Xiao-Yuan Liu Hao Wang Yumeng Shi Haoran Lin Quanyao Zhu Gang Li Hanlin Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第10期599-606,I0015,共9页
Ionic liquids(ILs)have been widely applied in the one-step fabrication of perovskite with noticeable enhancement in the device performance.However,in-depth mechanism of ionic-liquid-assisted perovskite film formation ... Ionic liquids(ILs)have been widely applied in the one-step fabrication of perovskite with noticeable enhancement in the device performance.However,in-depth mechanism of ionic-liquid-assisted perovskite film formation is not well understood for also important two-step perovskite fabrication method,with better control of crystallization behavior.In this work,we introduced ionic liquid methylammonium formate(MAFa)into organic salt to produce perovskite film via a two-step method.Systematic investigations on the influence of MAFa on the perovskite thin film formation mechanism were performed.Ionic liquid is shown to assist lowering the perovskite formation enthalpy upon the density functional theory(DFT)calculation,leading to an accelerated crystallization process evidenced by in-situ UV-Vis absorption measurement.A gradient up-down distribution of ionic liquid has been confirmed by timeof-flight SIMS.Importantly,besides the surface passivation,we found the HCOO-can diffuse into the perovskite crystals to fill up the halide vacancies,resulting in significant reduction of trap states.Uniform perovskite films with significantly larger grains and less defect density were prepared with the help of MAFa IL,and the corresponding device efficiency over 23%was obtained by two-step process with remarkably improved stability.This research work provides an efficient strategy to tune the morphology and opto-electronic properties of perovskite materials via ionic-liquid-assisted two-step fabrication method,which is beneficial for upscaling and application of perovskite photovoltaics. 展开更多
关键词 Halide vacancies Perovskite solar cells Two-step method Ionic liquid
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Cost-effectiveness of enhanced liver fibrosis test to assess liver fibrosis in chronic hepatitis C virus and alcoholic liver disease patients 被引量:2
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作者 Marcelo Soto Laura Sampietro-Colom +3 位作者 Luis Lasalvia Aurea Mira Wladimiro Jiménez Miquel Navasa 《World Journal of Gastroenterology》 SCIE CAS 2017年第17期3163-3173,共11页
AIM To assess liver fibrosis(LF)in hepatitis C virus(HCV)and alcoholic liver disease(ALD),estimate health outcomes and costs of new noninvasive testing strategies METHODS A Markov model was developed to simulate LF pr... AIM To assess liver fibrosis(LF)in hepatitis C virus(HCV)and alcoholic liver disease(ALD),estimate health outcomes and costs of new noninvasive testing strategies METHODS A Markov model was developed to simulate LF progression in HCV and ALD for a cohort of 40-yearold men with abnormal levels of transaminases.Three different testing alternatives were studied:a single liver biopsy;annual Enhanced liver fibrosis(ELF?)followed by liver stiffness measurement(LSM)imaging as a confirmation test if the ELF test is positive;and annual ELF test without LSM.The analysis was performed from the perspective of a university hospital in Spain.Clinical data were obtained from published literature.Costs were sourced from administrative databases of the hospital.Deterministic and probabilistic sensitivity analyses were performed.RESULTS In HCV patients,annual sequential ELF test/LSM and annual ELF test alone prevented respectively 12.9 and 13.3 liver fibrosis-related deaths per 100 persons tested,compared to biopsy.The incremental costeffectiveness ratios(ICERs)were respectively€13400 and€11500 per quality-adjusted life year(QALY).In ALD,fibrosis-related deaths decreased by 11.7 and 22.1 per 100 persons tested respectively with sequential ELF test/LSM and annual ELF test alone.ICERs were€280 and€190 per QALY,respectively.CONCLUSION The use of the ELF test with or without a confirmation LSM are cost-effective options compared to a single liver biopsy for testing liver fibrosis in HCV and ALD patients in Spain. 展开更多
关键词 Cost-effectiveness analysis Liver fibrosis Noninvasive diagnostic assessment Alcoholic liver disease Hepatitis C
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Hepatotoxicity associated with glucosamine and chondroitin sulfate in patients with chronic liver disease 被引量:2
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作者 Cristian Cerda Miguel Bruguera Albert Parés 《World Journal of Gastroenterology》 SCIE CAS 2013年第32期5381-5384,共4页
Glucosamine and chondroitin sulfate are molecules involved in the formation of articular cartilage and are frequently used for symptom relief in patients with arthrosis.These molecules are well tolerated with scarce s... Glucosamine and chondroitin sulfate are molecules involved in the formation of articular cartilage and are frequently used for symptom relief in patients with arthrosis.These molecules are well tolerated with scarce secondary effects.Very few cases of possible hepatotoxicity due to these substances have been described.The aim of this paper is to report the frequency of presumed glucosamine hepatotoxicity in patients with liver disease.A questionnaire was given to 151 consecutive patients with chronic liver disease of different etiology(mean age 59 years,56.9%women)attended in an outpatient clinic with the aim of evaluating the frequency of consumption of these drugs and determine whether their use coincided with a worsening in liver function test results.Twenty-three patients(15.2%)recognized having taken products containing glucosamine or chondroitin sulfate previously or at the time of the questionnaire.Review of the clinical records and liver function tests identified 2 patients presenting an elevation in aminotransferase values temporarily associated with glucosamine treatment;one of the cases simultaneously presented a skin rash attributed to the drug.Review of these two patients and the cases described in the literature suggest toxicity of glucosamine and chondroitin sulfate.The clinical spectrum is variable,and the mechanism of toxicity is not clear but may involve reactions of hypersensitivity.The consumption of products containing glucosamine and/or chondroitin sulfate is frequent among patients with chronic liver diseases and should be taken into account on the appearance of alterations in liver function tests not explained by the underlying disease. 展开更多
关键词 TOXIC HEPATITIS HEPATOTOXICITY GLUCOSAMINE CHONDROITIN sulphate OSTEOARTHRITIS
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Transcriptional Profi le by Cold Water Stress at the Booting Stage of japonica Rice 被引量:1
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作者 K.Y. Kim J.C. Ko +4 位作者 B.K. Kim K.I. Noh J.K. Ko Y.D. Kim C.K. Kim 《分子植物育种》 CAS CSCD 2007年第2期184-185,共2页
This study was carried out to identify molecular responses of the two varieties with different cold tolerance under cold water stress (13℃) at the booting stage. Transcriptional responses of the genes were analyzed in
关键词 冷水 刺激作用 种植技术 稻子
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Refinement of Bouguer anomalies derived from the EGM2008 model,impact on gravimetric signatures in mountainous region:Case of Cameroon Volcanic Line,Central Africa 被引量:1
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作者 Paul Gautier Kamto Cyrille Mezoue Adiang +2 位作者 Severin Nguiya Joseph Kamguia Loudi Yap 《Earth and Planetary Physics》 CSCD 2020年第6期639-650,共12页
Global geopotential models have not included the very high frequencies of the Earth’s external gravity field.This is called omission error.This omission error becomes more important in mountainous areas(areas with hi... Global geopotential models have not included the very high frequencies of the Earth’s external gravity field.This is called omission error.This omission error becomes more important in mountainous areas(areas with highly variable topography).The work reported here consists in reducing the omission error in measurements of Bouguer gravity anomalies,by refining the global geopotential model EGM2008 using the spectral enhancement method.This method consists in computing the residual terrain effects and then coupling them to the gravimetric signal of the global geopotential model.To compute the residual terrain effects,we used the Residual Terrain Model(RTM)technique.To refine it required a reference surface(ETOPO1)developed up to degree 2190(the maximum degree of the EGM2008 model)and a detailed elevation model(AW3D30).Computation was performed with the TC program of the GRAVSOFT package.The topography of the study area was assumed to have a constant density of 2670 kg/m3.For the inner and outer zones,the respective integration radii of 10 km and 200 km have been chosen.We obtained very important RTM values ranging from−53.59 to 34.79 mGal.These values were added to the gravity anomalies grid of the EGM2008 model to improve accuracy at high frequencies.On a part of the Cameroon Volcanic Line and its surroundings(mountainous area),we made a comparison between the residual Bouguer anomalies before and after refinement.We report differences ranging from−37.40 to 26.40 mGal.We conclude that the impact of omission error on gravimetric signatures is observed especially in areas with high variable topography,such as on the Cameroon Volcanic Line and around the localities of Takamanda,Essu,Dumbo,and Ngambe.This finding illustrates the great influence that topography has on accurate measurement of these gravity anomalies,and thus why topography must be taken into account.We can conclude that in preparing a global geopotential model,a high resolution DTM must be used to decrease the omission error:the degree of expansion has to increase in order to take the higher frequencies into account.The refined Bouguer anomalies grid presented here can be used in addition to terrestrial gravity anomalies in the study area,especially in mountainous areas where gravimetric data are very sparse or nonexistent. 展开更多
关键词 residual Terrain Model EGM2008 Omission error refined Bouguer anomalies mountainous area
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Precision medicine in sepsis and septic shock:From omics to clinical tools 被引量:2
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作者 Juan Carlos Ruiz-Rodriguez Erika P Plata-Menchaca +9 位作者 Luis Chiscano-Camón Adolfo Ruiz-Sanmartin Marcos Pérez-Carrasco Clara Palmada Vicent Ribas Mónica Martínez-Gallo Manuel Hernández-González Juan J Gonzalez-Lopez Nieves Larrosa Ricard Ferrer 《World Journal of Critical Care Medicine》 2022年第1期1-21,共21页
Sepsis is a heterogeneous disease with variable clinical course and several clinical phenotypes.As it is associated with an increased risk of death,patients with this condition are candidates for receipt of a very wel... Sepsis is a heterogeneous disease with variable clinical course and several clinical phenotypes.As it is associated with an increased risk of death,patients with this condition are candidates for receipt of a very well-structured and protocolized treatment.All patients should receive the fundamental pillars of sepsis management,which are infection control,initial resuscitation,and multiorgan support.However,specific subgroups of patients may benefit from a personalized approach with interventions targeted towards specific pathophysiological mechanisms.Herein,we will review the framework for identifying subpopulations of patients with sepsis,septic shock,and multiorgan dysfunction who may benefit from specific therapies.Some of these approaches are still in the early stages of research,while others are already in routine use in clinical practice,but together will help in the effective generation and safe implementation of precision medicine in sepsis. 展开更多
关键词 SEPSIS Septic shock Organ dysfunction Precision medicine Biomarkers PHENOTYPE Endotype
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GOECP/SEOR clinical recommendations for lung cancer radiotherapy during the COVID-19 pandemic
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作者 Felipe Couñago Arturo Navarro-Martin +7 位作者 Javier Luna Nuria Rodríguez de Dios Aurora Rodríguez Francesc Casas Rafael García Antonio Gómez-Caamaño Jorge Contreras Javier Serrano 《World Journal of Clinical Oncology》 CAS 2020年第8期510-527,共18页
The coronavirus disease 2019 crisis has had a major and highly complex impact on the clinical practice of radiation oncology worldwide.Spain is one of the countries hardest hit by the virus,with devastating consequenc... The coronavirus disease 2019 crisis has had a major and highly complex impact on the clinical practice of radiation oncology worldwide.Spain is one of the countries hardest hit by the virus,with devastating consequences.There is an urgent need to share experiences and offer guidance on decision-making with regard to the indications and standards for radiation therapy in the treatment of lung cancer.In the present article,the Oncological Group for the Study of Lung Cancer of the Spanish Society of Radiation Oncology reviews the literature and establishes a series of consensus-based recommendations for the treatment of patients with lung cancer in different clinical scenarios during the present pandemic. 展开更多
关键词 Lung cancer COVID-19 PANDEMIC RADIOTHERAPY RECOMMENDATIONS
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Enhanced tunable ultra-broadband multi-band NIR optical response in Bi-doped photonic glass and fibers by cation hybridization engineering
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作者 Weiwei Chen Min Ouyang +9 位作者 Xiongjian Huang Minbo Wu Bozhao Yin Anran Han Weibang Guo Puxian Xiong Xiudi Xiao Jianrong Qiu Zhongmin Yang Guoping Dong 《Science China Materials》 2025年第7期2288-2298,共11页
Bi-doped glass fibers with controllable optical response are essential for next-generation broadband amplifiers and tunable lasers.However,achieving broad wavelength tunability and stable near-infrared(NIR)emission re... Bi-doped glass fibers with controllable optical response are essential for next-generation broadband amplifiers and tunable lasers.However,achieving broad wavelength tunability and stable near-infrared(NIR)emission remains challenging due to limited structural modification of conventional silica glasses and variability of Bi active centers(BACs).Here,we propose a cation hybridization strategy to overcome these issues,demonstrating an enhanced ultra-broadband,multi-band NIR optical response in Bi-doped photonic glasses.Alkaline earth metal ions,such as Mg^(2+)and Ba^(2+),were employed as the hybrid cations to“repair”(Mg^(2+))and“tailor”(Ba^(2+))the flexible glass network of germanate glasses,enabling precise customization of the local environment to stabilize different BACs.Impressively,this enables a tunable optical response,ranging from one main peak emission at 1142 nm to a stable multi-band emission spanning 920,1142,1265,and 1516 nm,with an emission bandwidth of 526 nm,which is distinct from conventional rare-earth ions doped glasses.Furthermore,Bi-doped hybrid germanate glass fibers were fabricated and a positive on-off gain in multiple communication bands(O+E+S+C bands)was successfully achieved.The results offer new insights into the Bi NIR luminescence behavior and introduce a promising strategy for developing advanced photonic glass materials. 展开更多
关键词 photonic glass materials Bi-doped glass and fiber tunable luminescence near-infrared broadband optical response
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Organic–inorganic hybrid perovskite scintillators for mixed field radiation detection 被引量:5
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作者 Mengling Xia Guangda Niu +17 位作者 Linyue Liu Runlong Gao Tong Jin Pengying Wan Weicheng Pan Xianpeng Zhang Zuoxiang Xie Sam Teale Zenghua Cai Jiajun Luo Shan Zhao Haodi Wu Shiyou Chen Zhiping Zheng Qingguo Xie Xiaoping Ouyang Edward HSargent Jiang Tang 《InfoMat》 SCIE CAS 2022年第9期97-108,共12页
Sensitive and fast detection of neutrons and gamma rays is vital for homeland security,high-energy physics,and proton therapy.Fast-neutron detectors rely on light organic scintillators,andγ-ray detectors use heavy in... Sensitive and fast detection of neutrons and gamma rays is vital for homeland security,high-energy physics,and proton therapy.Fast-neutron detectors rely on light organic scintillators,andγ-ray detectors use heavy inorganic scintillators and semiconductors.Efficient mixed-field detection using a single material is highly challenging due to their contradictory requirements.Here we report hybrid perovskites(C_(8)H_(12)N)_(2)Pb(Br_(0.95)Cl_(0.05))_(4)that combine light organic cations and heavy inorganic skeletons at a molecular level to achieve unprecedented performance for mixed-field radiation detection.High neutron absorption due to a high density of hydrogen,strong radiative recombination within the highly confined[PbX_(6)]^(4-)layer,and sub-nanometer distance between absorption sites and radiative centers,enable a light yield of 41000 photons/MeV,detection pulse width of 2.97 ns and extraordinary linearity response toward both fast neutrons andγ-rays,outperforming commonly used fast-neutron scintillators.Neutron energy spectrum,time-of-flight based fast-neutron/γ-ray discrimination and neutron yield monitoring were all successfully achieved using(C_(8)H_(12)N)_(2)Pb(Br_(0.95)Cl_(0.05))_(4)detectors.We further demonstrate the monitoring of reaction kinetics and total power of a nuclear fusion reaction.We envision that molecular hybridized scintillators open a new avenue for mixed-field radiation detection and imaging. 展开更多
关键词 fast neutron mixed-field radiation detection organic-inorganic hybrid PEROVSKITE
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Layer-controlled nonlinear terahertz valleytronics in two-dimensional semimetal and semiconductor PtSe_(2) 被引量:2
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作者 Minoosh Hemmat Sabrine Ayari +16 位作者 Martin Micica Hadrien Vergnet Shasha Guo Mehdi Arfaoui Xuechao Yu Daniel Vala Adrien Wright Kamil Postava Juliette Mangeney Francesca Carosella Sihem Jaziri Qi Jie Wang Zheng Liu Jérôme Tignon Robson Ferreira Emmanuel Baudin Sukhdeep Dhillon 《InfoMat》 SCIE CSCD 2023年第11期49-63,共15页
Platinum diselenide(PtSe_(2))is a promising two-dimensional(2D)material for the terahertz(THz)range as,unlike other transition metal dichalcogenides(TMDs),its bandgap can be uniquely tuned from a semiconductor in the ... Platinum diselenide(PtSe_(2))is a promising two-dimensional(2D)material for the terahertz(THz)range as,unlike other transition metal dichalcogenides(TMDs),its bandgap can be uniquely tuned from a semiconductor in the nearinfrared to a semimetal with the number of atomic layers.This gives the material unique THz photonic properties that can be layer-engineered.Here,we demonstrate that a controlled THz nonlinearity—tuned from monolayer to bulk PtSe_(2)—can be realized in wafer size polycrystalline PtSe_(2)through the generation of ultrafast photocurrents and the engineering of the bandstructure valleys.This is combined with the PtSe_(2)layer interaction with the substrate for a broken material centrosymmetry,permitting a second order nonlinearity.Further,we show layer dependent circular dichroism,where the sign of the ultrafast currents and hence the phase of the emitted THz pulse can be controlled through the excitation of different bandstructure valleys.In particular,we show that a semimetal has a strong dichroism that is absent in the monolayer and few layer semiconducting limit.The microscopic origins of this TMD bandstructure engineering are highlighted through detailed DFT simulations,and shows the circular dichroism can be controlled when PtSe_(2)becomes a semimetal and when the K-valleys can be excited.As well as showing that PtSe_(2)is a promising material for THz generation through layer controlled optical nonlinearities,this work opens up a new class of circular dichroism materials beyond the monolayer limit that has been the case of traditional TMDs,and impacting a range of domains from THz valleytronics,THz spintronics to harmonic generation. 展开更多
关键词 2D transition metal dichalcogenides Dirac semimetal optical nonlinearities TERAHERTZ valleytronics
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性能与品位缺一不可 专访玛莎拉蒂全球商务总监尼科拉(Mr.Niccolai)和中国区代表克里斯(Mr.Gobber)
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《汽车与运动》 2007年第7期22-23,共2页
车卖到这样的价格,想必任何一位车主都会变得异常挑剔,当他们花了100多万元甚至200多万元之后,就会要求自己的车具有超凡脱俗的品质——性能和品位缺一不可。
关键词 玛莎拉蒂 MR Niccolai 克里斯 商务总监
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Biophotonic sensors with integrated Si_(3)N_(4)-organic hybrid (SiNOH) lasers for point-of-care diagnostics 被引量:9
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作者 Daria Kohler Gregor Schindler +5 位作者 Lothar Hahn Johannes Milvich Andreas Hofmann Kerstin Lange Wolfgang Freude Christian Koos 《Light: Science & Applications》 SCIE EI CAS CSCD 2021年第4期648-659,共12页
Early and efficient disease diagnosis with low-cost point-of-care devices is gaining importance for personalized medicine and public health protection.Within this context,waveguide-(WG)-based optical biosensors on the... Early and efficient disease diagnosis with low-cost point-of-care devices is gaining importance for personalized medicine and public health protection.Within this context,waveguide-(WG)-based optical biosensors on the siliconnitride(Si_(3)N_(4))platform represent a particularly promising option,offering highly sensitive detection of indicative biomarkers in multiplexed sensor arrays operated by light in the visible-wavelength range.However,while passive Si_(3)N_(4)-based photonic circuits lend themselves to highly scalable mass production,the integration of low-cost light sources remains a challenge.In this paper,we demonstrate optical biosensors that combine Si_(3)N_(4)sensor circuits with hybrid on-chip organic lasers.These Si_(3)N_(4)-organic hybrid(SiNOH)lasers rely on a dye-doped cladding material that are deposited on top of a passive WG and that are optically pumped by an external light source.Fabrication of the devices is simple:The underlying Si_(3)N_(4)WGs are structured in a single lithography step,and the organic gain medium is subsequently applied by dispensing,spin-coating,or ink-jet printing processes.A highly parallel read-out of the optical sensor signals is accomplished with a simple camera.In our proof-of-concept experiment,we demonstrate the viability of the approach by detecting different concentrations of fibrinogen in phosphate-buffered saline solutions with a sensor-length(L-)-related sensitivity of S/L=0.16 rad nM^(-1)mm^(-1).To our knowledge,this is the first demonstration of an integrated optical circuit driven by a co-integrated low-cost organic light source.We expect that the versatility of the device concept,the simple operation principle,and the compatibility with cost-efficient mass production will make the concept a highly attractive option for applications in biophotonics and point-of-care diagnostics. 展开更多
关键词 PASSIVE WAVEGUIDE PUMPED
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Low-loss silicon core fibre platform for mid-infrared nonlinear photonics
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作者 Haonan Ren Li Shen +4 位作者 Antoine F.J.Runge Thomas W.Hawkins John Ballato Ursula Gibson Anna C.Peacock 《Light: Science & Applications》 SCIE EI CAS CSCD 2019年第1期202-211,共10页
Broadband mid-infrared light sources are highly desired for wide-ranging applications that span free-space communications to spectroscopy.In recent years,silicon has attracted great interest as a platform for nonlinea... Broadband mid-infrared light sources are highly desired for wide-ranging applications that span free-space communications to spectroscopy.In recent years,silicon has attracted great interest as a platform for nonlinear optical wavelength conversion in this region,owing to its low losses(linear and nonlinear)and high stability.However,most research in this area has made use of small core waveguides fabricated from silicon-on-insulator platforms,which suffer from high absorption losses of the use of silica cladding,limiting their ability to generate light beyond 3μm.Here,we design and demonstrate a compact silicon core,silica-clad waveguide platform that has low losses across the entire silicon transparency window.The waveguides are fabricated from a silicon core fibre that is tapered to engineer mode properties to ensure efficient nonlinear propagation in the core with minimal interaction of the mid-infrared light with the cladding.These waveguides exhibit many of the benefits of fibre platforms,such as a high coupling efficiency and power handling capability,allowing for the generation of mid-infrared supercontinuum spectra with high brightness and coherence spanning almost two octaves(1.6-5.3μm). 展开更多
关键词 WAVEGUIDE FIBRE NONLINEAR
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Crystal and electronic structure engineering of tin monoxide by external pressure
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作者 Kun LI Junjie WANG +5 位作者 Vladislav ABLATOV Yutong GONG NaotoUMEZAWA Tomofumi TADA Hideo HOSONO Artem ROGANOV 《Journal of Advanced Ceramics》 SCIE CAS CSCD 2021年第3期565-577,共13页
Although tin monoxide (SnO) is an interesting compound due to its p-type conductivity,a widespread application of SnO has been limited by its narrow band gap of 0.7 eV.In this work,we theoretically investigate the str... Although tin monoxide (SnO) is an interesting compound due to its p-type conductivity,a widespread application of SnO has been limited by its narrow band gap of 0.7 eV.In this work,we theoretically investigate the structural and electronic properties of several SnO phases under high pressures through employing van der Waals (vdW) functionals.Our calculations reveal that a metastable SnO (β-SnO),which possesses space group P2_(1)/c and a wide band gap of 1.9 eV,is more stable than α-SnO at pressures higher than 80 GPa.Moreover,a stable (space group P2/c) and a metastable (space group Pnma) phases of SnO appear at pressures higher than 120 GPa.Energy and topological analyses show that P2/c-SnO has a high possibility to directly transform to β-SnO at around 120 GPa.Our work also reveals that β-SnO is a necessary intermediate state between high-pressure phase Pnma-SnO and low-pressure phase α-SnO for the phase transition path Pnma-SnO →β-SnO →α-SnO.Two phase transition analyses indicate that there is a high possibility to synthesize β-SnO under high-pressure conditions and have it remain stable under normal pressure.Finally,our study reveals that the conductive property of β-SnO can be engineered in a low-pressure range (0-9 GPa)through a semiconductor-to-metal transition,while maintaining transparency in the visible light range. 展开更多
关键词 tin monoxide van der Waals(vdW) topological relationship phase transition band gap
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Dynamics and cytokinic regulation of immune cell infiltration in genetically engineered mouse models of pancreatic cancer dictate the sensitivity to immunotherapy
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作者 Okan Safak Shenghan Wang +16 位作者 Carmen Mota Reyes Ibrahim Halil Gürcinar Sergey Tokalov Nedim Can Cevik Kivanc Görgülü Bengi Su Yilmaz Emre Erdogan Linhan Ye Qiaolin Li Elif Arik Sever SamedÖzer Güldal Süyen Helmut Friess Güralp Onur Ceyhan Rouzanna Istvanffy Hana Algül Ihsan Ekin Demir 《Cancer Communications》 SCIE 2024年第1期178-182,共5页
Dear Editor,Targeting the immune compartment in pancreatic duc-tal adenocarcinoma(PDAC)holds promise for prognostic improvement,yet our knowledge on the spatial and tem-poral dynamics and the molecular modulators of t... Dear Editor,Targeting the immune compartment in pancreatic duc-tal adenocarcinoma(PDAC)holds promise for prognostic improvement,yet our knowledge on the spatial and tem-poral dynamics and the molecular modulators of the PDAC-associated immunophenotype is scarce. 展开更多
关键词 IMMUNE ADENOCARCINOMA IMMUNOTHERAPY
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On-chip frequency combs and telecommunications signal processing meet quantum optics
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作者 Christian REIMER Yanbing ZHANG +13 位作者 Piotr ROZTOCKI Stefania SCIARA Luis Romero CORTES Mehedi ISLAM Bennet FISCHER Benjamin WETZEL Alfonso Carmelo CINO Sai Tak CHU Brent LITTLE David MOSS Lucia CASPANI Jose AZANA Michael KUES Roberto MORANDOTTI 《Frontiers of Optoelectronics》 EI CSCD 2018年第2期134-147,共14页
Entangled optical quantum states are essential towards solving questions in fundamental physics and are at the heart of applications in quantum information science. For advancing the research and development of quantu... Entangled optical quantum states are essential towards solving questions in fundamental physics and are at the heart of applications in quantum information science. For advancing the research and development of quantum technologies, practical access to the generation and manipulation of photon states carrying significant quantum resources is required. Recently, integrated photonics has become a leading platform for the compact and cost- efficient generation and processing of optical quantum states. Despite significant advances, most on-chip non- classical light sources are still limited to basic bi-photon systems formed by two-dimensional states (i.e., qubits). An interesting approach beating large potential is the use of the time or frequency domain to enabled the scalable on- chip generation of complex states. In this manuscript, we review recent efforts in using on-chip optical frequency combs for quantum state generation and telecommunica- tions components for their coherent control. In particular, the generation of bi- and multi-photon entangled qubit states has been demonstrated, based on a discrete time domain approach. Moreover, the on-chip generation of high-dimensional entangled states (quDits) has recentlybeen realized, wherein the photons are created in a coherent superposition of multiple pure frequency modes. The time- and frequency-domain states formed with on-chip frequency comb sources were coherently manipulated via off-the-shelf telecommunications compo- nents. Our results suggest that microcavity-based entangled photon states and their coherent control using accessible telecommunication infrastructures can open up new venues for scalable quantum information science. 展开更多
关键词 nonlinear optics quantum optics entangledphotons
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西山煤田屯兰区块煤层气低产井的增产改造措施及效果分析
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作者 王昱 宋晓夏 +6 位作者 胡咤咤 刘彦飞 杜立强 祁炜 阎纪伟 郭浩 陈伟东 《河南理工大学学报(自然科学版)》 北大核心 2025年第3期101-111,共11页
西山煤田屯兰区块煤层气开发已具一定规模,但部分煤层气井产气效果未达到预期,亟待开展针对性的增产改造措施,以期提高气井产量。目的为了探究屯兰区块煤层气井的初次压裂改造特征与低产井的增产改造效果,方法以屯兰区块煤层气井的地质... 西山煤田屯兰区块煤层气开发已具一定规模,但部分煤层气井产气效果未达到预期,亟待开展针对性的增产改造措施,以期提高气井产量。目的为了探究屯兰区块煤层气井的初次压裂改造特征与低产井的增产改造效果,方法以屯兰区块煤层气井的地质和工程资料为基础,气井产量为依据,102口直井和7口水平井为研究对象,压裂曲线类型、破裂压力特征与产能特征为切入点,分析研究区内煤层气井的初次压裂改造特征,采用生产动态分析方法探讨加密煤层气井井网技术对低产井的增产效果。结果结果表明,屯兰区块煤层气井初次压裂改造时压裂曲线类型可划分为稳定型、下降型、上升型、波动型4种,其中,下降型和稳定型压裂曲线更有利于煤层气抽采;研究区中波动型和上升型曲线类型占比偏高,反映了煤层破裂难度较大、非均质性较强;通过在先导试验区进行加密煤层气井井网增产改造,在直井间加密布设7口水平井,其附近9口低产直井的平均日产气量显著提高,由150~800 m3/d提升至330~6000 m3/d,验证了该技术的有效性;研究区内煤层气井产气量低的主要原因是煤储层原始渗透率低、初次压裂改造不充分,加密煤层气井井网技术是一种行之有效的低产井增产改造措施。结论研究结果可为本区或类似地区煤层气低产井增产改造提供指导与借鉴。 展开更多
关键词 煤层气 屯兰区块 压裂曲线类型 产能特征 增产改造措施
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Impact fracturing of rock-like material using carbon dioxide under different temperatures and pressures 被引量:1
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作者 Shaobin Hu Zhengyong Yan +2 位作者 Chun Zhu Manchao He Shuogang Pang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期370-384,共15页
Unconventional resources (oil, gas, and geothermal) are often buried deep underground within dense rock strata and complex geological structures, making it increasingly difficult to create volumetric fractures through... Unconventional resources (oil, gas, and geothermal) are often buried deep underground within dense rock strata and complex geological structures, making it increasingly difficult to create volumetric fractures through conventional hydraulic fracturing. This paper introduces a novel method of supercritical energetic fluid thermal shock fracturing. It pioneers a CO_(2) deflagration impact triaxial pneumatic fracturing experimental system, using high-strength similar materials to simulate deep, hard rock masses. The study investigates the rock-breaking process and crack propagation patterns under supercritical CO_(2) thermal shock, revealing and discussing the types of thermal shock-induced fractures, their formation conditions, and discrimination criteria. The research indicates that higher supercritical CO_(2) thermal shock pressures and faster pressure release rates facilitate the formation of radial branching fractures, circumferential cracks, and branch cracks. Typically, CO_(2) thermal shock generates 3–5 radial main cracks, which is significantly more than the single main crack formed by hydraulic fracturing. The formation of branched cracks is often caused by compression-shear failure and occurs under relatively harsh conditions, determined by the confining pressure, rock properties, peak thermal shock pressure, and the pressure sustained post-decompression. The findings are expected to offer a safe, efficient, and controllable shockwave method of supercritical fluid thermal shock fracturing for the exploitation of deep unconventional oil and gas resources. 展开更多
关键词 Cracking mechanism Supercritical CO_(2) True triaxial experimental Impact fracturing
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Unusual ovarian hyperstimulation syndrome presentation:Pleural effusion without ascites.A case report
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作者 Íngrid Solsona Sara Peralta +2 位作者 Yasmina Barral Francisco Fàbregues Pepita Giménez-Bonafé 《World Journal of Clinical Cases》 SCIE 2025年第8期26-34,共9页
BACKGROUND Ovarian hyperstimulation syndrome(OHSS)is a life-threatening complication that can occur in the luteal phase or early pregnancy after controlled ovarian stimulation.This case report highlights a unique mani... BACKGROUND Ovarian hyperstimulation syndrome(OHSS)is a life-threatening complication that can occur in the luteal phase or early pregnancy after controlled ovarian stimulation.This case report highlights a unique manifestation of OHSS involving pleural effusion(PE)in a patient without identifiable risk factors.CASE SUMMARY A 39-year-old woman who underwent controlled ovarian hyperstimulation for an in vitro fertilization(IVF)cycle experienced dyspnea on the eleventh day of post oocyte retrieval.The diagnosis was severe OHSS with a unique manifestation of PE without ascites.Clinical management involved fluid balance and treatment with albumin,furosemide,thromboembolic prophylaxis,and thoracentesis.A continued drainage of the pleural cavity was performed.The patient had a favo-rable outcome,and a dichorionic diamniotic gestation passed without incident.CONCLUSION OHSS and its potential complications can include respiratory distress and PE,as well as thromboembolic disorders. 展开更多
关键词 DYSPNEA INFERTILITY In vitro fertilization Ovarian hyperstimulation syndrome Pleural effusion THORACENTESIS Case report
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