Metal-halide perovskites are revolutionizing the world of X-ray detectors,due to the development of sensitive,fast,and cost-effective devices.Self-powered operation,ensuring portability and low power consumption,has a...Metal-halide perovskites are revolutionizing the world of X-ray detectors,due to the development of sensitive,fast,and cost-effective devices.Self-powered operation,ensuring portability and low power consumption,has also been recently demonstrated in both bulk materials and thin films.However,the signal stability and repeatability under continuous X-ray exposure has only been tested up to a few hours,often reporting degradation of the detection performance.Here it is shown that self-powered direct X-ray detectors,fabricated starting from a FAPbBr_(3)submicrometer-thick film deposition onto a mesoporous TiO_(2)scaffold,can withstand a 26-day uninterrupted X-ray exposure with negligible signal loss,demonstrating ultra-high operational stability and excellent repeatability.No structural modification is observed after irradiation with a total ionizing dose of almost 200 Gy,revealing an unexpectedly high radiation hardness for a metal-halide perovskite thin film.In addition,trap-assisted photoconductive gain enabled the device to achieve a record bulk sensitivity of 7.28 C Gy^(−1)cm^(−3)at 0 V,an unprecedented value in the field of thin-film-based photoconductors and photodiodes for“hard”X-rays.Finally,prototypal validation under the X-ray beam produced by a medical linear accelerator for cancer treatment is also introduced.展开更多
As a dendritic cell-specific C-type lectin receptor, DC-SIGN plays an important role in the early stages of many viral infections, including HIV and Ebola, making it an interesting therapeutic target. It has been foun...As a dendritic cell-specific C-type lectin receptor, DC-SIGN plays an important role in the early stages of many viral infections, including HIV and Ebola, making it an interesting therapeutic target. It has been found that DC-SIGN can recognize both highly mannosylated and branched fucosylated oligosaccharides. Herein, we synthesized a new series of homo-and Man-Fuc heteroglycoclusters with diverse structures. The binding properties of these compounds to tetrameric extracellular DC-SIGN were assessed by surface plasmon resonance(SPR). Heteroglycocluster 17 b showed high DC-SIGN-binding activity(K;= 2.6 μM). The structural determinants of this high affinity of 17 b were rationalized by docking and compared with its much less potent isomer 17 a. Therefore, 17 b might serve as a base for the development of potent inhibitors of DC-SIGN-dependent viral infection.展开更多
This investigation presents a generally applicable framework for parameterizing interatomic potentials to accurately capture large deformation pathways.It incorporates a multi-objective genetic algorithm,training and ...This investigation presents a generally applicable framework for parameterizing interatomic potentials to accurately capture large deformation pathways.It incorporates a multi-objective genetic algorithm,training and screening property sets,and correlation and principal component analyses.The framework enables iterative definition of properties in the training and screening sets,guided by correlation relationships between properties,aiming to achieve optimal parametrizations for properties of interest.Specifically,the performance of increasingly complex potentials,Buckingham,Stillinger-Weber,Tersoff,and modified reactive empirical bond-order potentials are compared.Using MoSe_(2)as a case study,we demonstrate good reproducibility of training/screening properties and superior transferability.For MoSe_(2),the best performance is achieved using the Tersoff potential,which is ascribed to its apparent higher flexibility embedded in its functional form.These results should facilitate the selection and parametrization of interatomic potentials for exploring mechanical and phononic properties of a large library of two-dimensional and bulk materials.展开更多
The objective of this study was to determine the concentrations of the metabolites of four selected phthalates, widely used industrial chemicals which possess endocrine-disrupting properties, in samples of amniotic fl...The objective of this study was to determine the concentrations of the metabolites of four selected phthalates, widely used industrial chemicals which possess endocrine-disrupting properties, in samples of amniotic fluid and maternal urine collected in the same day, in order to verify if the latter can be considered a measure of the fetal exposure. The quantitative determination of the metabolites was carried out by HPLC-MS/MS with isotopic dilution from 70 pregnant volunteers. Detectable concentrations of phthalates metabolites were found in amniotic fluids. As phthalate monoesters are excreted in the urine conjugated with glucuronic acid, an enzymatic hydrolysis is carried out before analysis. Amniotic fluids were tested with and without hydrolysis and only the free phthalate metabolites, not conjugated with glucuronic acid, were found. The concentration of metabolites after enzymatic hydrolysis in maternal urine is not correlated to those of amniotic fluids, but the free form concentrations are. These results suggest that only the free forms can cross the placenta. A significant number of mothers showed urine phthalate monoesters concentrations higher than non-pregnant women.展开更多
This article reviews the current evidence and knowledge of progressive liver fibrosis after pediatric liver transplantation.This often-silent histologic finding is common in long-term survivors and may lead to allogra...This article reviews the current evidence and knowledge of progressive liver fibrosis after pediatric liver transplantation.This often-silent histologic finding is common in long-term survivors and may lead to allograft dysfunction in advanced stages.Surveillance through protocolized liver allograft biopsy remains the gold standard for diagnosis,and recent evidence suggests that chronic inflammation precedes fibrosis.展开更多
Recently based in the performance of tunnels under seismic movements a good progress is made in the seismic design of tunnels. The majority of problems in the tunnel structures take place in near fault conditions and ...Recently based in the performance of tunnels under seismic movements a good progress is made in the seismic design of tunnels. The majority of problems in the tunnel structures take place in near fault conditions and in the case of great variation of rock properties. Not having a previous experience in the seismic design of the tunnels that pass through tectonic zones with very large heterogeneity （strong rock-soil or very poor rock that behaves like soil） this article presents the general aspects of seismic calculation of tunnels and application in a specific example. The article presents the methods of seismic input modeling, design and particularities of numerical calculations. The geological conditions in which the case study tunnel will be constructed are very common in Albanian territory and represent one of the most difficult cases for the construction of road tunnels. The applied approach for using the longitudinal models for generating time histories of acceleration that can be used as input for transversal models is very simple and will help the designers for the seismic analysis of other tunnels that will be constructed in Albania.展开更多
Inflammatory bowel disease (IBD) including Crohn (CD) and ulcerative colitis (UC), is intestinal disorders with an unknown specific etiology. Many factors are involved in the pathogenesis: genetic, environment, nutrit...Inflammatory bowel disease (IBD) including Crohn (CD) and ulcerative colitis (UC), is intestinal disorders with an unknown specific etiology. Many factors are involved in the pathogenesis: genetic, environment, nutrition, immunity and intestinal dysbiosis. In the present work, we review the most important trigger mechanisms involved in IBD, with a particular regard to the role of microbiota and fecal mass transplantation as a new therapeutic approach, that even if it can be considered safe and effective, data are necessary regarding all procedures not yet standardized and timing of treatment.展开更多
The Energy Dispersive X-ray Diffraction, generally referred as EDXD, has shown to be a valid alternative to the conventional Angular Dispersive X-ray Diffraction, the ADXD. EDXD exhibits several advantages to its AD c...The Energy Dispersive X-ray Diffraction, generally referred as EDXD, has shown to be a valid alternative to the conventional Angular Dispersive X-ray Diffraction, the ADXD. EDXD exhibits several advantages to its AD counterpart, mainly related to the properties of the polychromatic X-ray beam utilized for diffracting, such as higher signal intensities, a wider accessible region of the reciprocal space, a greater transparency of samples, and a parallel data collection of the q-points in the diffraction pattern acquisition. However, the main drawback of poly-chromaticity lays in the fact that the quantities that modulate the scattered intensity in a diffraction measurement depend on the energy. These quantities are the primary X-ray beam spectrum, polarization, and X-ray absorption, the last producing by far the most critical effect because it rapidly changes as a function of energy. Therefore, a detailed knowledge of the energy dependence of all these quantities is required in EDXD in order to process the data correctly and prevent systematic errors. The difficulty in handling the energy-dependent factors complicates the experimental procedure and may make the measurements unreliable. In the present paper, a hybrid method between the ED and AD X-ray Diffraction is proposed to maintain the advantages of the polychromatic nature of the radiation utilized in EDXD, while preventing the problems produced by the energy-dependent quantities.展开更多
1. Introduction In recent years, the need to face major global challenges has made it necessary to review strategies that address multifaceted contexts. Economic, societal, environnlental, and technological dimensions...1. Introduction In recent years, the need to face major global challenges has made it necessary to review strategies that address multifaceted contexts. Economic, societal, environnlental, and technological dimensions all act together as major drivers for change, and science and technology （S＆T） programs aimed at research and development （R＆D）-performing communities constitute an impor- tant asset in generating emerging and breakthrough solutions in the international transition toward the knowledge economy.展开更多
This paper was published online on Chin.Phys.C,42(3):033104(2018)with the Fig.2 being partly missing.The Fig.2 should be corrected as follows:Fig.2.(color online)(a)Various ratios of the production cross section for Z...This paper was published online on Chin.Phys.C,42(3):033104(2018)with the Fig.2 being partly missing.The Fig.2 should be corrected as follows:Fig.2.(color online)(a)Various ratios of the production cross section for Z'as functions of energy√s,normalized by the cross section when Z'couples to light quarks u and d at LHC with √s=13 TeV.The solid black curve shows the ratios of the contribution from u and d to that from b and t.The dotted vertical line indicates √s=13 TeV.(b)The mass limit for SSM Z'(dashed black line)from dilepton searches shifts when the signal strength is reduced by factors of 10(dashed blue)and 100(dot-dashed purple).展开更多
基金supported by the project“PARIDE”(Perovskite Advanced Radiotherapy&Imaging Detectors),funded under the Regional Research and Innovation Programme POR-FESR Lazio 2014-2020(project number:A0375-2020-36698).
文摘Metal-halide perovskites are revolutionizing the world of X-ray detectors,due to the development of sensitive,fast,and cost-effective devices.Self-powered operation,ensuring portability and low power consumption,has also been recently demonstrated in both bulk materials and thin films.However,the signal stability and repeatability under continuous X-ray exposure has only been tested up to a few hours,often reporting degradation of the detection performance.Here it is shown that self-powered direct X-ray detectors,fabricated starting from a FAPbBr_(3)submicrometer-thick film deposition onto a mesoporous TiO_(2)scaffold,can withstand a 26-day uninterrupted X-ray exposure with negligible signal loss,demonstrating ultra-high operational stability and excellent repeatability.No structural modification is observed after irradiation with a total ionizing dose of almost 200 Gy,revealing an unexpectedly high radiation hardness for a metal-halide perovskite thin film.In addition,trap-assisted photoconductive gain enabled the device to achieve a record bulk sensitivity of 7.28 C Gy^(−1)cm^(−3)at 0 V,an unprecedented value in the field of thin-film-based photoconductors and photodiodes for“hard”X-rays.Finally,prototypal validation under the X-ray beam produced by a medical linear accelerator for cancer treatment is also introduced.
基金National Natural Science Foundation of China(NSFC,Grant No.21172015)Wellcome Trust (UK,Grant No.097354/Z/11/Z)+1 种基金ML acknowledges the Research Project RVO61388963 of the Institute of Organic Chemistry and BiochemistryAcademy of Sciences of the Czech Republic,the Czech Science Foundation (Grant No.P20 8/12/G016)。
文摘As a dendritic cell-specific C-type lectin receptor, DC-SIGN plays an important role in the early stages of many viral infections, including HIV and Ebola, making it an interesting therapeutic target. It has been found that DC-SIGN can recognize both highly mannosylated and branched fucosylated oligosaccharides. Herein, we synthesized a new series of homo-and Man-Fuc heteroglycoclusters with diverse structures. The binding properties of these compounds to tetrameric extracellular DC-SIGN were assessed by surface plasmon resonance(SPR). Heteroglycocluster 17 b showed high DC-SIGN-binding activity(K;= 2.6 μM). The structural determinants of this high affinity of 17 b were rationalized by docking and compared with its much less potent isomer 17 a. Therefore, 17 b might serve as a base for the development of potent inhibitors of DC-SIGN-dependent viral infection.
基金The authors acknowledge the support of the National Science Foundation,through award CMMI 1953806computational resources provided by the Center of Nanoscale Materials at Argonne National Laboratory,as well as the Quest High Performance Computing Cluster at Northwestern University.Use of the Center for Nanoscale Materials,an Office of Science user facility,was supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences,under Contract No.DE-AC02-06CH11357The authors acknowledge Dr.Henry Chan for the helpful discussions and suggestions.
文摘This investigation presents a generally applicable framework for parameterizing interatomic potentials to accurately capture large deformation pathways.It incorporates a multi-objective genetic algorithm,training and screening property sets,and correlation and principal component analyses.The framework enables iterative definition of properties in the training and screening sets,guided by correlation relationships between properties,aiming to achieve optimal parametrizations for properties of interest.Specifically,the performance of increasingly complex potentials,Buckingham,Stillinger-Weber,Tersoff,and modified reactive empirical bond-order potentials are compared.Using MoSe_(2)as a case study,we demonstrate good reproducibility of training/screening properties and superior transferability.For MoSe_(2),the best performance is achieved using the Tersoff potential,which is ascribed to its apparent higher flexibility embedded in its functional form.These results should facilitate the selection and parametrization of interatomic potentials for exploring mechanical and phononic properties of a large library of two-dimensional and bulk materials.
文摘The objective of this study was to determine the concentrations of the metabolites of four selected phthalates, widely used industrial chemicals which possess endocrine-disrupting properties, in samples of amniotic fluid and maternal urine collected in the same day, in order to verify if the latter can be considered a measure of the fetal exposure. The quantitative determination of the metabolites was carried out by HPLC-MS/MS with isotopic dilution from 70 pregnant volunteers. Detectable concentrations of phthalates metabolites were found in amniotic fluids. As phthalate monoesters are excreted in the urine conjugated with glucuronic acid, an enzymatic hydrolysis is carried out before analysis. Amniotic fluids were tested with and without hydrolysis and only the free phthalate metabolites, not conjugated with glucuronic acid, were found. The concentration of metabolites after enzymatic hydrolysis in maternal urine is not correlated to those of amniotic fluids, but the free form concentrations are. These results suggest that only the free forms can cross the placenta. A significant number of mothers showed urine phthalate monoesters concentrations higher than non-pregnant women.
文摘This article reviews the current evidence and knowledge of progressive liver fibrosis after pediatric liver transplantation.This often-silent histologic finding is common in long-term survivors and may lead to allograft dysfunction in advanced stages.Surveillance through protocolized liver allograft biopsy remains the gold standard for diagnosis,and recent evidence suggests that chronic inflammation precedes fibrosis.
文摘Recently based in the performance of tunnels under seismic movements a good progress is made in the seismic design of tunnels. The majority of problems in the tunnel structures take place in near fault conditions and in the case of great variation of rock properties. Not having a previous experience in the seismic design of the tunnels that pass through tectonic zones with very large heterogeneity （strong rock-soil or very poor rock that behaves like soil） this article presents the general aspects of seismic calculation of tunnels and application in a specific example. The article presents the methods of seismic input modeling, design and particularities of numerical calculations. The geological conditions in which the case study tunnel will be constructed are very common in Albanian territory and represent one of the most difficult cases for the construction of road tunnels. The applied approach for using the longitudinal models for generating time histories of acceleration that can be used as input for transversal models is very simple and will help the designers for the seismic analysis of other tunnels that will be constructed in Albania.
文摘Inflammatory bowel disease (IBD) including Crohn (CD) and ulcerative colitis (UC), is intestinal disorders with an unknown specific etiology. Many factors are involved in the pathogenesis: genetic, environment, nutrition, immunity and intestinal dysbiosis. In the present work, we review the most important trigger mechanisms involved in IBD, with a particular regard to the role of microbiota and fecal mass transplantation as a new therapeutic approach, that even if it can be considered safe and effective, data are necessary regarding all procedures not yet standardized and timing of treatment.
文摘The Energy Dispersive X-ray Diffraction, generally referred as EDXD, has shown to be a valid alternative to the conventional Angular Dispersive X-ray Diffraction, the ADXD. EDXD exhibits several advantages to its AD counterpart, mainly related to the properties of the polychromatic X-ray beam utilized for diffracting, such as higher signal intensities, a wider accessible region of the reciprocal space, a greater transparency of samples, and a parallel data collection of the q-points in the diffraction pattern acquisition. However, the main drawback of poly-chromaticity lays in the fact that the quantities that modulate the scattered intensity in a diffraction measurement depend on the energy. These quantities are the primary X-ray beam spectrum, polarization, and X-ray absorption, the last producing by far the most critical effect because it rapidly changes as a function of energy. Therefore, a detailed knowledge of the energy dependence of all these quantities is required in EDXD in order to process the data correctly and prevent systematic errors. The difficulty in handling the energy-dependent factors complicates the experimental procedure and may make the measurements unreliable. In the present paper, a hybrid method between the ED and AD X-ray Diffraction is proposed to maintain the advantages of the polychromatic nature of the radiation utilized in EDXD, while preventing the problems produced by the energy-dependent quantities.
文摘1. Introduction In recent years, the need to face major global challenges has made it necessary to review strategies that address multifaceted contexts. Economic, societal, environnlental, and technological dimensions all act together as major drivers for change, and science and technology （S＆T） programs aimed at research and development （R＆D）-performing communities constitute an impor- tant asset in generating emerging and breakthrough solutions in the international transition toward the knowledge economy.
文摘This paper was published online on Chin.Phys.C,42(3):033104(2018)with the Fig.2 being partly missing.The Fig.2 should be corrected as follows:Fig.2.(color online)(a)Various ratios of the production cross section for Z'as functions of energy√s,normalized by the cross section when Z'couples to light quarks u and d at LHC with √s=13 TeV.The solid black curve shows the ratios of the contribution from u and d to that from b and t.The dotted vertical line indicates √s=13 TeV.(b)The mass limit for SSM Z'(dashed black line)from dilepton searches shifts when the signal strength is reduced by factors of 10(dashed blue)and 100(dot-dashed purple).
