AIM： To evaluate contrast-enhanced ultrasonography （CEUS） using SonoVue in the detection of liver metastases in patients with known extrahepatic primary tumors versus the combined gold standard comprising CT, MRI a...AIM： To evaluate contrast-enhanced ultrasonography （CEUS） using SonoVue in the detection of liver metastases in patients with known extrahepatic primary tumors versus the combined gold standard comprising CT, MRI and clinical/histological data. METHODS： It is an international multicenter study, and there were 12 centres and 125 patients （64 males, 61 females, aged 59 ± 11 years） involved, with 102 patients per protocol. Primary tumors were colorectal in 35%, breast in 27%, pancreatic in 17% and others in 21%. CEUS using SonoVue was employed with a Iow-mechanical-index technique and contrast-specific software using Siemens Elegra, Philips HDI 5000 and Acuson Sequoia; continuous scanning for at least five minutes. RESULTS： CEUS with SonoVue increased significantly the number of focal liver lesions detected versus unenhanced sonography. In 31.4% of the patients, more lesions were found after contrast enhancement. The total numbers of lesions detected were comparable with CEUS （55）, triple-phase spiral CT （61） and HRI with a liverspecific contrast agent （53）. Accuracy of detection of metastatic disease （i.e. at least one metastatic lesion） was significantly higher for CEUS （91.2%） than for unenhanced sonography （81.4%） and was similar to that of triple-phase spiral CT （89.2 %）. In 53 patients whose CEUS examination was negative, a follow-up examination 3-6 months later confirmed the absence of metastatic lesions in 50 patients （94.4%）. CONCLUSION： CEUS is proved to be reliable in the detection of liver metastases in patients with known extrahepatic primary tumors and suspected liver lesions.展开更多
AIM： To evaluate in a multicenter study whether the sonographic characterization of focal liver lesions can be improved using SonoVue-enhancement; and to compare this method with computed tomography （CT） and magnet...AIM： To evaluate in a multicenter study whether the sonographic characterization of focal liver lesions can be improved using SonoVue-enhancement; and to compare this method with computed tomography （CT） and magnetic resonance imaging （MRI）. METHODS： One hundred and thirty four patients withone focal liver lesion detected in baseline ultrasound （US） were examined with conventional US, contrastenhanced US （n = 134）, contrast-enhanced CT （n = 115） and/or dynamic contrast-enhanced MRI （n = 70）. The lesions were classified as malignant, benign or indeterminate and the type of lesion was determined. The final diagnosis based on the combined information of all imaging examinations, clinical information and histology （n = 32） was used. Comparisons were made to see whether the addition of contrast-enhanced US led to the improvement of the characterization of doubtful focal liver lesions.RESULTS： In comparison with unenhanced US, SonoVue markedly improves sensitivity and specificity for the characterization （malignant/benign） of focal liver lesions. In comparison with CT and/or dynamic MRI, SonoVue -enhanced sonography applied for characterization of focal liver lesions was 30.2% more sensitive in the recognition of malignancy and 16.1% more specific in the exclusion of malignancy and overall 22.9% more accurate. In the subgroup with confirmative histology available （n = 30）, sensitivity was 95.5% （CEUS）, 72.2% （CT） and 81.8% （MRI）, and specificity was 75.0% （CEUS）, 37.5% （CT） and 42.9% （MRI）. The sensitivity and specificity of CEUS for the identification of focal nodular hyperplasia （FNH） and hemangiomas was 100% and 87%, resulting in an accuracy of 94.5%.CONCLUSION： SonoVue-enhanced sonography emerges as the most sensitive, ost specific and thus most accurate imaging modality for the characterization of focal liver lesions.展开更多
AIM：To clarify the expression patterns and prognostic implications of the mitotic regulator Polo-like kinase 1 （PLK1） in colon cancer. METHODS： Expression of PLK1 was investigated by immunohistochemistry （158 ca...AIM：To clarify the expression patterns and prognostic implications of the mitotic regulator Polo-like kinase 1 （PLK1） in colon cancer. METHODS： Expression of PLK1 was investigated by immunohistochemistry （158 cases） and immunoblotting in tissue of colon adenomas and adenocarcinomas. PLK1 expression patterns were correlated with clinicopathological parameters and patient prognosis. In addition, expression of PLK1 was evaluated by immunoblot and PCR in colon carcinoma cell lines, and coexpression of PLK1 with the proliferation marker Ki-67 was investigated. RESULTS： Weak PLK1 expression was observed in normal colon mucosa and adenomas. In contrast, 66.7% of carcinomas showed strong expression of PLK1. Overexpression of PLK1 correlated positively with Dukes stage （P〈0.001）, tumor stage （P = 0.001） and nodal status （P〈0.05）. Additionally, PLK1 expression was a prognostic marker in univariate survival analysis （P〈0.01） and had independent prognostic significance （RR = 3.3, P = 0.02） in patients with Iocoregional disease. Expression of PLK1 mRNA and protein was detected in all cell lines investigated. Coexpression of PLK1 and Ki-67 was observed in the majority of colon cancer cells, but a considerable proportion of cells showed PLK1 positivity without Ki-67 expression. CONCLUSION： PLK1 is a new prognostic marker for colon carcinoma patients and may be involved in tumorigenesis and progression of colon cancer. Strategies focusing on PLK1 inhibitionin vivo might therefore represent a promising new therapeutic approach for this tumor entity. 2005 The WIG Press and Elsevier Inc. All rights reserved展开更多
We present algorithms that allow for reat-time rendering of 3D-scenes with a watercolor painting appearance,Our approach provides an appropriate simplification of the visual complexity,initates characteristic natural ...We present algorithms that allow for reat-time rendering of 3D-scenes with a watercolor painting appearance,Our approach provides an appropriate simplification of the visual complexity,initates characteristic natural effects of watercolor,and provides two essential painting techniques,the wet-on-wet and the wet-on-dry painting.We concentrate on efficient algorithms based on image space processing rather than on an exact simulation.This allows for the real-time rendering of 3D-scenes.During an animation a high frame-to-frame coherence can be achieved due to a stable segmentation scheme.Finally,we seamlessly integrate a smooth illumination into the watercolor renderings nsing information from the 3D-scenc.展开更多
Electrocatalytic carb on dioxide reducti on(CO_(2)R)presents a promising route to establish zero-e mission carb on cycle and store in termittent ren ewable energy into chemical fuels for steady energy supply.Methanol ...Electrocatalytic carb on dioxide reducti on(CO_(2)R)presents a promising route to establish zero-e mission carb on cycle and store in termittent ren ewable energy into chemical fuels for steady energy supply.Methanol is an ideal energy carrier as alternative fuels and one of the most important commodity chemicals.Nevertheless,methanol is currently mainly produced from fossil-based syngas,the production of which yields tremendous carb on emission globally.Direct CO_(2)R towards metha nol poses great potential to shift the paradigm of methanol production.In this perspective,we focus our discussions on producing methanol from electrochemical CO_(2)R,using metallomacrocyclic molecules as the model catalysts.We discuss the motivation of having methanol as the sole CO_(2)R product,the documented application of metallomacrocyclic catalysts for CO_(2)R,and recent advance in catalyzing CO_(2) to methanol with cobalt phthalocyanine-based catalysts.We attempt to understand the key factors in determining the activity,selectivity,and stability of electrocatalytic CO_(2)-to-methanol conversion,and to draw mechanistic insights from existing observations.Finally,we identify the challenges hindering methanol electrosynthesis directly from CO_(2) and some intriguing directions worthy of further investigation and exploration.展开更多
In this review we consider the development of optical near-field imaging and nanostructuring by means of laser ablation since its early stages around the turn of the century.The interaction of short,intense laser puls...In this review we consider the development of optical near-field imaging and nanostructuring by means of laser ablation since its early stages around the turn of the century.The interaction of short,intense laser pulses with nanoparticles on a surface leads to laterally tightly confined,strongly enhanced electromagnetic fields below and around the nano-objects,which can easily give rise to nanoablation.This effect can be exploited for structuring substrate surfaces on a length scale well below the diffraction limit,one to two orders smaller than the incident laser wavelength.We report on structure formation by the optical near field of both dielectric and metallic nano-objects,the latter allowing even stronger and more localized enhancement of the electromagnetic field due to the excitation of plasmon modes.Structuring with this method enables one to nanopattern large areas in a one-step parallel process with just one laser pulse irradiation,and in the course of time various improvements have been added to this technique,so that also more complex and even arbitrary structures can be produced by means of nanoablation.The near-field patterns generated on the surface can be read out with high resolution techniques like scanning electron microscopy and atomic force microscopy and provide thus a valuable tool-in conjunction with numerical calculations like finite difference time domain(FDTD)simulations-for a deeper understanding of the optical and plasmonic properties of nanostructures and their applications.展开更多
Computational study of molecules and materials from first principles is a cornerstone of physics,chemistry,and materials science,but limited by the cost of accurate and precise simulations.In settings involving many s...Computational study of molecules and materials from first principles is a cornerstone of physics,chemistry,and materials science,but limited by the cost of accurate and precise simulations.In settings involving many simulations,machine learning can reduce these costs,often by orders of magnitude,by interpolating between reference simulations.This requires representations that describe any molecule or material and support interpolation.We comprehensively review and discuss current representations and relations between them.For selected state-of-the-art representations,we compare energy predictions for organic molecules,binary alloys,and Al–Ga–In sesquioxides in numerical experiments controlled for data distribution,regression method,and hyper-parameter optimization.展开更多
Animals must strike a balance between anti-predation behavior and other essential behaviors,such as foraging.Within the same species,strategies may vary on individuals’risk-taking preferences,and in this process the ...Animals must strike a balance between anti-predation behavior and other essential behaviors,such as foraging.Within the same species,strategies may vary on individuals’risk-taking preferences,and in this process the environment is a determinant,in addition to predator regime.The Crested Ibis(Nipponia nippon)exhibits such tendency.This is an endangered species,once inhabiting exclusively in China’s Qinling Mountain.This used to be the sole remaining wild population.However,over recent decades,this population has expanded.A portion has relocated to breed in the lower plain area,which is characterized by elevated level of human activities and landscape complexity.We used flight initiation distance(FID)as an indicator of the ibises’risk-taking preference,particularly their response to human proximity.Additionally,we examined the environmental factors influencing their foraging site selection,including altitude,terrain openness,human activity intensity and human construction.Our findings revealed a significantly shorter FID among individuals relocating to plain habitats,indicating a higher tolerance of human proximity.The results showed that FID decreased with distance to the nearest human settlement.Another finding is that FID was independent of instant human activity intensity and environmental factors(altitude and terrain openness).These different may arise from various combinations of human activity,predation risk,and food abundance within the two habitats.These results provide insights into the in situ conservation of the threatened species within the context of global urbanization.展开更多
The realization of spatiotemporal vortex structure of various physical fields with transverse orbital angular momentum(OAM)has attracted much attention and is expected to expand the research scope and open new opportu...The realization of spatiotemporal vortex structure of various physical fields with transverse orbital angular momentum(OAM)has attracted much attention and is expected to expand the research scope and open new opportunities in their respective fields.Here we present theoretically the first,to the best of our knowledge,study on the generation of attosecond pulse trains featuring a spatiotemporal optical vortex(STOV)structure by a twocolor femtosecond light field,with each color carrying transverse OAM.Through careful optimization of relative phase and intensity ratio,we validate the efficient upconversion of the infrared pulse into its tens of order harmonics,showing that each harmonic preserves a corresponding intact topological charge.This unique characteristic enables the synthesis of an extreme ultraviolet attosecond pulse train with transverse OAM.In addition,we reveal that ionization depletion plays an outsize role therein.Our studies pave the way for the generation and utilization of light fields with STOV in the attosecond regime.展开更多
1|INTRODUCTION Chirality spans over almost every size range,from mole-cules to biological systems and even to galaxies.It is one of the fascinating geometrical properties with a lot of amazing manifestations in the ma...1|INTRODUCTION Chirality spans over almost every size range,from mole-cules to biological systems and even to galaxies.It is one of the fascinating geometrical properties with a lot of amazing manifestations in the material world.As chemi-cal researchers,we are more interested in chirality at the molecular scale and nanoscale.Chiral molecules are found important in life science,agrochemicals,pharma-ceutical industries,biosensing,display materials,and so forth.1–5 Chirality stems from a structure lacking sym-metry elements of inversion symmetry and mirror‐plane,which makes the structure not superimposable with its mirror image.Without these two kinds of symmetries,any structure is chiral,besides conventional chiral organics or spiral inorganic structures.The essence of chirality is the stereochemistry of molecules or nanostructures.展开更多
Sheep were domesticated in the Fertile Crescent and then spread globally,where they have been encountering various environmental conditions.The Tibetan sheep has adapted to high altitudes on the Qinghai-Tibet Plateau ...Sheep were domesticated in the Fertile Crescent and then spread globally,where they have been encountering various environmental conditions.The Tibetan sheep has adapted to high altitudes on the Qinghai-Tibet Plateau over the past 3000 years.To explore genomic variants associated with high-altitude adaptation in Tibetan sheep,we analyzed Illumina short-reads of 994 whole genomes representing∼60 sheep breeds/populations at varied altitudes,PacBio High fidelity(HiFi)reads of 13 breeds,and 96 transcriptomes from 12 sheep organs.Association testing between the inhabited altitudes and 34,298,967 variants was conducted to investigate the genetic architecture of altitude adaptation.Highly accurate HiFi reads were used to complement the current ovine reference assembly at the most significantly associatedβ-globin locus and to validate the presence of two haplotypes A and B among 13 sheep breeds.The haplotype A carried two homologous gene clusters:(1)HBE1,HBE2,HBB-like,and HBBC,and(2)HBE1-like,HBE2-like,HBB-like,and HBB;while the haplotype B lacked the first cluster.The high-altitude sheep showed highly frequent or nearly fixed haplotype A,while the low-altitude sheep dominated by haplotype B.We further demonstrated that sheep with haplotype A had an increased hemoglobin–O_(2) affinity compared with those carrying haplotype B.Another highly associated genomic region contained the EGLN1 gene which showed varied expression between high-altitude and low-altitude sheep.Our results provide evidence that the rapid adaptive evolution of advantageous alleles play an important role in facilitating the environmental adaptation of Tibetan sheep.展开更多
Lipoteichoic acids(LTAs)are macroamphiphiles composed of alditol,lipid,phosphate,and carbohydrate units.Due to their inherent complexity,it is a severe challenge to access LTAs with structural integrity from natural s...Lipoteichoic acids(LTAs)are macroamphiphiles composed of alditol,lipid,phosphate,and carbohydrate units.Due to their inherent complexity,it is a severe challenge to access LTAs with structural integrity from natural sources for biological or immunological evaluation.Here,we describe the first total synthesis of Lactococcus garvieae LTA(type II LTA),containing five distinct 1,2-cis gluco/galactopyranosidic linkages,via a novel additive-modulated O-glycosyl trichloroacetimidate preactivation glycosidation strategy.This strategy features(1)high glycosidation yields and excellent 1,2-cis stereoselectivities independent of the donor anomeric configuration,(2)common and inexpensive reagents as promoters and additives,(3)application to standard glycosyl imidate donors without resorting to participating protection,and(4)general application to reactive and less reactive glycosyl acceptors.Thus,via the precise stereocontrolled construction of three galactopyranosidic and two glucopyranosidic bonds on a multigram scale,a series of structurally well-defined LTA molecules were successfully assembled.Immunological evaluation of these type II synthetic LTAs showed a structure–activity relationship in the stimulation of a proinflammatory response.展开更多
Intra-individual variation in cognitive abilities has been widely reported in animals.Recent studies have found that individual cognitive performance varies with personality traits in a wide range of animal taxa,with ...Intra-individual variation in cognitive abilities has been widely reported in animals.Recent studies have found that individual cognitive performance varies with personality traits in a wide range of animal taxa,with a speed-accuracy trade-off between cognition and personality traits.Few studies investigated whether these relationships change depending on different contexts.Here we investigate whether the personality trait(as measured by exploratory behavior in a novel environment)is associated with cognition(novel skill learning and spatial memory)in wild male chestnut thrushes Turdus rubrocanus.Using an experimental novel skill-learning task set-up,we found that fast-exploring individuals explored the experimental device(a cardboard with 8 opaque cups)sooner than slow-exploring individuals.Exploratory behavior was not associated with individual spatial memory performances or an individual’s capacity to learn the novel skill.Learning speed was positively associated with the difficulty of learning phases,and fast-exploring individuals used less trials to meet the learning criterion.In addition,fast-exploring individuals took less time to complete the 24-h spatial memory test,but the accuracy of the test was not significantly different between individuals who were more or less exploratory.We suggest that variation in personality traits associates with individual learning speed in cognitive tasks and that this relationship is context-dependent.展开更多
The application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction,named as gate-controlled supercurrent(GCS),has raised great interest for fundamental an...The application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction,named as gate-controlled supercurrent(GCS),has raised great interest for fundamental and technological reasons.To gain a deeper understanding of this effect and develop superconducting technologies based on it,the material and physical parameters crucial for the GCS effect must be identified.Top-down fabrication protocols should also be optimized to increase device scalability,although studies suggest that top-down fabricated devices are more resilient to show a GCS.Here,we investigate gated superconducting nanobridges made with a top-down fabrication process from thin films of the noncentrosymmetric superconductor niobium rhenium with varying ratios of the constituents(NbRe).Unlike other devices previously reported and made with a top-down approach,our NbRe devices systematically exhibit a GCS effect when they were fabricated from NbRe thin films with small grain size and etched in specific conditions.These observations pave the way for the realization of top-down-made GCS devices with high scalability.Our results also imply that physical parameters like structural disorder and surface physical properties of the nanobridges,which can be in turn modified by the fabrication process,are crucial for a GCS observation,providing therefore also important insights into the physics underlying the GCS effect.展开更多
The uplift of the Tibetan Plateau significantly altered the geomorphology and climate of the Euroasia by creating large mountains and rivers.Fishes are more likely to be affected relative to other organisms,as they ar...The uplift of the Tibetan Plateau significantly altered the geomorphology and climate of the Euroasia by creating large mountains and rivers.Fishes are more likely to be affected relative to other organisms,as they are largely restricted to river systems.Faced with the rapidly flowing water in the Tibetan Plateau,a group of catfish has evolved greatly enlarged pectoral fins with more numbers of fin-rays to form an adhesive apparatus.However,the genetic basis of these adaptations in Tibetan catfishes remains elusive.In this study,we performed comparative genomic analyses based on the chromosome-level genome of Glyptosternum maculatum in family Sisoridae and detected some proteins with conspicuously high evolutionary rates in particular in genes involved in skeleton development,energy metabolism,and hypoxia response.We found that the hoxd12a gene evolved faster and a loss-of-function assay of hoxd12a supports a potential role for this gene in shaping the enlarged fins of these Tibetan catfishes.Other genes with amino acid replacements and signatures of positive selection included proteins involved in low temperature(TRMU)and hypoxia(VHL)responses.Functional assays reveal that the G.maculatum TRMU allele generates more mitochondrial ATP than the ancestral allele found in low-altitude fishes.Functional assays of VHL alleles suggest that the G.maculatum allele has lower transactivation activity than the low-altitude forms.These findings provide a window into the genomic underpinnings of physiological adaptations that permit G.maculatum to survive in the harsh environment of the Tibetan Himalayas that mirror those that are convergently found in other vertebrates such as humans.展开更多
Agro-ecological conditions associated with the spread and persistence of highly pathogenic avian inlfuenza （HPAI） are not well understood, but the trade of live poultry is suspected to be a major pathway. Although m...Agro-ecological conditions associated with the spread and persistence of highly pathogenic avian inlfuenza （HPAI） are not well understood, but the trade of live poultry is suspected to be a major pathway. Although market chains of live bird trade have been studied through indirect means including interviews and questionnaires, direct methods have not been used to identify movements of individual poultry. To bridge the knowledge gap on quantitative movement and transportation of poultry, we introduced a novel approach for applying telemetry to document domestic duck movements from source farms at Poyang Lake, China. We deployed recently developed transmitters that record Global Positioning System （GPS） locations and send them through the Groupe Spécial Mobile （GSM） cellular telephone system. For the ifrst time, we were able to track individually marked ducks from 3 to 396 km from their origin to other farms, distribution facilities, or live bird markets. Our proof of concept test showed that the use of GPS-GSM transmitters may provide di-rect, quantitative information to document the movement of poultry and reveal their market chains. Our ifndings provide an initial indication of the complexity of source-market network connectivity and highlight the great potential for future telemetry studies in poultry network analyses.展开更多
Environmental conditions change constantly either by anthropogenic perturbation or naturally across space and time.Often,a change in behavior is the frst response to changing conditions.Behavioral fexibility can poten...Environmental conditions change constantly either by anthropogenic perturbation or naturally across space and time.Often,a change in behavior is the frst response to changing conditions.Behavioral fexibility can potentially improve an organism’s chances to survive and reproduce.Currently,we lack an understanding on the time-scale such behavioral adjustments need,how they actually affect reproduction and survival and whether behavioral adjustments are suffcient in keeping up with changing conditions.We used house mice(Mus musculus)to test whether personality and life-history traits can adjust to an experimentally induced food-switch fexibly in adulthood or by intergenerational plasticity,that is,adjustments only becoming visible in the offspring generation.Mice lived in 6 experimental populations of semi-natural environments either on high or standard quality food for 4 generations.We showed previously that high-quality food induced better conditions and a less risk-prone personality.Here,we tested whether the speed and/or magnitude of adjustment shows condition-dependency and whether adjustments incur ftness effects.Life-history but not personality traits reacted fexibly to a food-switch,primarily by a direct reduction of reproduction and sloweddown growth.Offspring whose parents received a food-switch developed a more active stress-coping personality and gained weight at a slower rate compared with their respective controls.Furthermore,the modulation of most traits was condition-dependent,with animals previously fed with high-quality food showing stronger responses.Our study highlights that life-history and personality traits adjust at different speed toward environmental change,thus,highlighting the importance of the environment and the mode of response for evolutionary models.展开更多
文摘AIM： To evaluate contrast-enhanced ultrasonography （CEUS） using SonoVue in the detection of liver metastases in patients with known extrahepatic primary tumors versus the combined gold standard comprising CT, MRI and clinical/histological data. METHODS： It is an international multicenter study, and there were 12 centres and 125 patients （64 males, 61 females, aged 59 ± 11 years） involved, with 102 patients per protocol. Primary tumors were colorectal in 35%, breast in 27%, pancreatic in 17% and others in 21%. CEUS using SonoVue was employed with a Iow-mechanical-index technique and contrast-specific software using Siemens Elegra, Philips HDI 5000 and Acuson Sequoia; continuous scanning for at least five minutes. RESULTS： CEUS with SonoVue increased significantly the number of focal liver lesions detected versus unenhanced sonography. In 31.4% of the patients, more lesions were found after contrast enhancement. The total numbers of lesions detected were comparable with CEUS （55）, triple-phase spiral CT （61） and HRI with a liverspecific contrast agent （53）. Accuracy of detection of metastatic disease （i.e. at least one metastatic lesion） was significantly higher for CEUS （91.2%） than for unenhanced sonography （81.4%） and was similar to that of triple-phase spiral CT （89.2 %）. In 53 patients whose CEUS examination was negative, a follow-up examination 3-6 months later confirmed the absence of metastatic lesions in 50 patients （94.4%）. CONCLUSION： CEUS is proved to be reliable in the detection of liver metastases in patients with known extrahepatic primary tumors and suspected liver lesions.
文摘AIM： To evaluate in a multicenter study whether the sonographic characterization of focal liver lesions can be improved using SonoVue-enhancement; and to compare this method with computed tomography （CT） and magnetic resonance imaging （MRI）. METHODS： One hundred and thirty four patients withone focal liver lesion detected in baseline ultrasound （US） were examined with conventional US, contrastenhanced US （n = 134）, contrast-enhanced CT （n = 115） and/or dynamic contrast-enhanced MRI （n = 70）. The lesions were classified as malignant, benign or indeterminate and the type of lesion was determined. The final diagnosis based on the combined information of all imaging examinations, clinical information and histology （n = 32） was used. Comparisons were made to see whether the addition of contrast-enhanced US led to the improvement of the characterization of doubtful focal liver lesions.RESULTS： In comparison with unenhanced US, SonoVue markedly improves sensitivity and specificity for the characterization （malignant/benign） of focal liver lesions. In comparison with CT and/or dynamic MRI, SonoVue -enhanced sonography applied for characterization of focal liver lesions was 30.2% more sensitive in the recognition of malignancy and 16.1% more specific in the exclusion of malignancy and overall 22.9% more accurate. In the subgroup with confirmative histology available （n = 30）, sensitivity was 95.5% （CEUS）, 72.2% （CT） and 81.8% （MRI）, and specificity was 75.0% （CEUS）, 37.5% （CT） and 42.9% （MRI）. The sensitivity and specificity of CEUS for the identification of focal nodular hyperplasia （FNH） and hemangiomas was 100% and 87%, resulting in an accuracy of 94.5%.CONCLUSION： SonoVue-enhanced sonography emerges as the most sensitive, ost specific and thus most accurate imaging modality for the characterization of focal liver lesions.
文摘AIM：To clarify the expression patterns and prognostic implications of the mitotic regulator Polo-like kinase 1 （PLK1） in colon cancer. METHODS： Expression of PLK1 was investigated by immunohistochemistry （158 cases） and immunoblotting in tissue of colon adenomas and adenocarcinomas. PLK1 expression patterns were correlated with clinicopathological parameters and patient prognosis. In addition, expression of PLK1 was evaluated by immunoblot and PCR in colon carcinoma cell lines, and coexpression of PLK1 with the proliferation marker Ki-67 was investigated. RESULTS： Weak PLK1 expression was observed in normal colon mucosa and adenomas. In contrast, 66.7% of carcinomas showed strong expression of PLK1. Overexpression of PLK1 correlated positively with Dukes stage （P〈0.001）, tumor stage （P = 0.001） and nodal status （P〈0.05）. Additionally, PLK1 expression was a prognostic marker in univariate survival analysis （P〈0.01） and had independent prognostic significance （RR = 3.3, P = 0.02） in patients with Iocoregional disease. Expression of PLK1 mRNA and protein was detected in all cell lines investigated. Coexpression of PLK1 and Ki-67 was observed in the majority of colon cancer cells, but a considerable proportion of cells showed PLK1 positivity without Ki-67 expression. CONCLUSION： PLK1 is a new prognostic marker for colon carcinoma patients and may be involved in tumorigenesis and progression of colon cancer. Strategies focusing on PLK1 inhibitionin vivo might therefore represent a promising new therapeutic approach for this tumor entity. 2005 The WIG Press and Elsevier Inc. All rights reserved
文摘We present algorithms that allow for reat-time rendering of 3D-scenes with a watercolor painting appearance,Our approach provides an appropriate simplification of the visual complexity,initates characteristic natural effects of watercolor,and provides two essential painting techniques,the wet-on-wet and the wet-on-dry painting.We concentrate on efficient algorithms based on image space processing rather than on an exact simulation.This allows for the real-time rendering of 3D-scenes.During an animation a high frame-to-frame coherence can be achieved due to a stable segmentation scheme.Finally,we seamlessly integrate a smooth illumination into the watercolor renderings nsing information from the 3D-scenc.
基金financial support through the StartUp Fund for Outstanding Talent with grant number A1098531023601307the National University of Singapore and Ministry of Education in Singapore for its financial support through Tier-1 projects with grant numbers R-279000-622-133 and R-279-000-622-731.
文摘Electrocatalytic carb on dioxide reducti on(CO_(2)R)presents a promising route to establish zero-e mission carb on cycle and store in termittent ren ewable energy into chemical fuels for steady energy supply.Methanol is an ideal energy carrier as alternative fuels and one of the most important commodity chemicals.Nevertheless,methanol is currently mainly produced from fossil-based syngas,the production of which yields tremendous carb on emission globally.Direct CO_(2)R towards metha nol poses great potential to shift the paradigm of methanol production.In this perspective,we focus our discussions on producing methanol from electrochemical CO_(2)R,using metallomacrocyclic molecules as the model catalysts.We discuss the motivation of having methanol as the sole CO_(2)R product,the documented application of metallomacrocyclic catalysts for CO_(2)R,and recent advance in catalyzing CO_(2) to methanol with cobalt phthalocyanine-based catalysts.We attempt to understand the key factors in determining the activity,selectivity,and stability of electrocatalytic CO_(2)-to-methanol conversion,and to draw mechanistic insights from existing observations.Finally,we identify the challenges hindering methanol electrosynthesis directly from CO_(2) and some intriguing directions worthy of further investigation and exploration.
文摘In this review we consider the development of optical near-field imaging and nanostructuring by means of laser ablation since its early stages around the turn of the century.The interaction of short,intense laser pulses with nanoparticles on a surface leads to laterally tightly confined,strongly enhanced electromagnetic fields below and around the nano-objects,which can easily give rise to nanoablation.This effect can be exploited for structuring substrate surfaces on a length scale well below the diffraction limit,one to two orders smaller than the incident laser wavelength.We report on structure formation by the optical near field of both dielectric and metallic nano-objects,the latter allowing even stronger and more localized enhancement of the electromagnetic field due to the excitation of plasmon modes.Structuring with this method enables one to nanopattern large areas in a one-step parallel process with just one laser pulse irradiation,and in the course of time various improvements have been added to this technique,so that also more complex and even arbitrary structures can be produced by means of nanoablation.The near-field patterns generated on the surface can be read out with high resolution techniques like scanning electron microscopy and atomic force microscopy and provide thus a valuable tool-in conjunction with numerical calculations like finite difference time domain(FDTD)simulations-for a deeper understanding of the optical and plasmonic properties of nanostructures and their applications.
基金This work received funding from the European Union’s Horizon 2020 Research and Innovation Programme,Grant Agreements No.676580,the NOMAD Laboratory CoE,and No.740233,ERC:TEC1PIt was funded in part by the German Ministry for Education and Research as BIFOLD-Berlin Institute for the Foundations of Learning and Data(ref.01IS18025A and ref.01IS18037A)Part of the research was performed while the authors visited the Institute for Pure and Applied Mathematics(IPAM),which is supported by the National Science Foundation(Grant No.DMS-1440415).
文摘Computational study of molecules and materials from first principles is a cornerstone of physics,chemistry,and materials science,but limited by the cost of accurate and precise simulations.In settings involving many simulations,machine learning can reduce these costs,often by orders of magnitude,by interpolating between reference simulations.This requires representations that describe any molecule or material and support interpolation.We comprehensively review and discuss current representations and relations between them.For selected state-of-the-art representations,we compare energy predictions for organic molecules,binary alloys,and Al–Ga–In sesquioxides in numerical experiments controlled for data distribution,regression method,and hyper-parameter optimization.
基金supported by National Natural Science Foundation of China(No.32270554 to CD)。
文摘Animals must strike a balance between anti-predation behavior and other essential behaviors,such as foraging.Within the same species,strategies may vary on individuals’risk-taking preferences,and in this process the environment is a determinant,in addition to predator regime.The Crested Ibis(Nipponia nippon)exhibits such tendency.This is an endangered species,once inhabiting exclusively in China’s Qinling Mountain.This used to be the sole remaining wild population.However,over recent decades,this population has expanded.A portion has relocated to breed in the lower plain area,which is characterized by elevated level of human activities and landscape complexity.We used flight initiation distance(FID)as an indicator of the ibises’risk-taking preference,particularly their response to human proximity.Additionally,we examined the environmental factors influencing their foraging site selection,including altitude,terrain openness,human activity intensity and human construction.Our findings revealed a significantly shorter FID among individuals relocating to plain habitats,indicating a higher tolerance of human proximity.The results showed that FID decreased with distance to the nearest human settlement.Another finding is that FID was independent of instant human activity intensity and environmental factors(altitude and terrain openness).These different may arise from various combinations of human activity,predation risk,and food abundance within the two habitats.These results provide insights into the in situ conservation of the threatened species within the context of global urbanization.
基金National Natural Science Foundation of China(12034013,12204308,11925405)Shanghai Science and Technology Commission(22ZR1444100)。
文摘The realization of spatiotemporal vortex structure of various physical fields with transverse orbital angular momentum(OAM)has attracted much attention and is expected to expand the research scope and open new opportunities in their respective fields.Here we present theoretically the first,to the best of our knowledge,study on the generation of attosecond pulse trains featuring a spatiotemporal optical vortex(STOV)structure by a twocolor femtosecond light field,with each color carrying transverse OAM.Through careful optimization of relative phase and intensity ratio,we validate the efficient upconversion of the infrared pulse into its tens of order harmonics,showing that each harmonic preserves a corresponding intact topological charge.This unique characteristic enables the synthesis of an extreme ultraviolet attosecond pulse train with transverse OAM.In addition,we reveal that ionization depletion plays an outsize role therein.Our studies pave the way for the generation and utilization of light fields with STOV in the attosecond regime.
文摘1|INTRODUCTION Chirality spans over almost every size range,from mole-cules to biological systems and even to galaxies.It is one of the fascinating geometrical properties with a lot of amazing manifestations in the material world.As chemi-cal researchers,we are more interested in chirality at the molecular scale and nanoscale.Chiral molecules are found important in life science,agrochemicals,pharma-ceutical industries,biosensing,display materials,and so forth.1–5 Chirality stems from a structure lacking sym-metry elements of inversion symmetry and mirror‐plane,which makes the structure not superimposable with its mirror image.Without these two kinds of symmetries,any structure is chiral,besides conventional chiral organics or spiral inorganic structures.The essence of chirality is the stereochemistry of molecules or nanostructures.
基金supported by the Tibetan R&D Program,China(Grant No.XZ202101ZD0001N)the China Agriculture Research System(Grant No.CARS-39)the National Natural Science Foundation of China(Grant Nos.31900313,32161143010,and 31972526).
文摘Sheep were domesticated in the Fertile Crescent and then spread globally,where they have been encountering various environmental conditions.The Tibetan sheep has adapted to high altitudes on the Qinghai-Tibet Plateau over the past 3000 years.To explore genomic variants associated with high-altitude adaptation in Tibetan sheep,we analyzed Illumina short-reads of 994 whole genomes representing∼60 sheep breeds/populations at varied altitudes,PacBio High fidelity(HiFi)reads of 13 breeds,and 96 transcriptomes from 12 sheep organs.Association testing between the inhabited altitudes and 34,298,967 variants was conducted to investigate the genetic architecture of altitude adaptation.Highly accurate HiFi reads were used to complement the current ovine reference assembly at the most significantly associatedβ-globin locus and to validate the presence of two haplotypes A and B among 13 sheep breeds.The haplotype A carried two homologous gene clusters:(1)HBE1,HBE2,HBB-like,and HBBC,and(2)HBE1-like,HBE2-like,HBB-like,and HBB;while the haplotype B lacked the first cluster.The high-altitude sheep showed highly frequent or nearly fixed haplotype A,while the low-altitude sheep dominated by haplotype B.We further demonstrated that sheep with haplotype A had an increased hemoglobin–O_(2) affinity compared with those carrying haplotype B.Another highly associated genomic region contained the EGLN1 gene which showed varied expression between high-altitude and low-altitude sheep.Our results provide evidence that the rapid adaptive evolution of advantageous alleles play an important role in facilitating the environmental adaptation of Tibetan sheep.
基金supported by the National Natural Science Foundation of China(grant nos.21977063,92053110,and 22177061)the National Key Research and Development Program of China(grant no.2018YFA0902000)+3 种基金the China Postdoctoral Science Foundation(grant no.2020M680090)the Qilu Youth Scholar Program of Shandong University,the Central Government Guide Local Science and Technology Development Funds(grant no.YDZX20203700002579)the Nonprofit Central Research Institute Fund of Chinese Academy of Medical Sciences(grant no.2021-RC350-002)the CAMS Innovation Fund for Medical Sciences(CIFMS)(grant no.2021-1-I2M-026).
文摘Lipoteichoic acids(LTAs)are macroamphiphiles composed of alditol,lipid,phosphate,and carbohydrate units.Due to their inherent complexity,it is a severe challenge to access LTAs with structural integrity from natural sources for biological or immunological evaluation.Here,we describe the first total synthesis of Lactococcus garvieae LTA(type II LTA),containing five distinct 1,2-cis gluco/galactopyranosidic linkages,via a novel additive-modulated O-glycosyl trichloroacetimidate preactivation glycosidation strategy.This strategy features(1)high glycosidation yields and excellent 1,2-cis stereoselectivities independent of the donor anomeric configuration,(2)common and inexpensive reagents as promoters and additives,(3)application to standard glycosyl imidate donors without resorting to participating protection,and(4)general application to reactive and less reactive glycosyl acceptors.Thus,via the precise stereocontrolled construction of three galactopyranosidic and two glucopyranosidic bonds on a multigram scale,a series of structurally well-defined LTA molecules were successfully assembled.Immunological evaluation of these type II synthetic LTAs showed a structure–activity relationship in the stimulation of a proinflammatory response.
基金supported by the National Natural Science Foundation of China(32070452).
文摘Intra-individual variation in cognitive abilities has been widely reported in animals.Recent studies have found that individual cognitive performance varies with personality traits in a wide range of animal taxa,with a speed-accuracy trade-off between cognition and personality traits.Few studies investigated whether these relationships change depending on different contexts.Here we investigate whether the personality trait(as measured by exploratory behavior in a novel environment)is associated with cognition(novel skill learning and spatial memory)in wild male chestnut thrushes Turdus rubrocanus.Using an experimental novel skill-learning task set-up,we found that fast-exploring individuals explored the experimental device(a cardboard with 8 opaque cups)sooner than slow-exploring individuals.Exploratory behavior was not associated with individual spatial memory performances or an individual’s capacity to learn the novel skill.Learning speed was positively associated with the difficulty of learning phases,and fast-exploring individuals used less trials to meet the learning criterion.In addition,fast-exploring individuals took less time to complete the 24-h spatial memory test,but the accuracy of the test was not significantly different between individuals who were more or less exploratory.We suggest that variation in personality traits associates with individual learning speed in cognitive tasks and that this relationship is context-dependent.
基金the European Union’s Horizon 2020 Research and Innovation Program under Grant Agreement No.964398(SuperGate)the US ONR(Nos.N00014-21-1-2879,N00014-20-1-2442,and N00014-23-1-2866).
文摘The application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction,named as gate-controlled supercurrent(GCS),has raised great interest for fundamental and technological reasons.To gain a deeper understanding of this effect and develop superconducting technologies based on it,the material and physical parameters crucial for the GCS effect must be identified.Top-down fabrication protocols should also be optimized to increase device scalability,although studies suggest that top-down fabricated devices are more resilient to show a GCS.Here,we investigate gated superconducting nanobridges made with a top-down fabrication process from thin films of the noncentrosymmetric superconductor niobium rhenium with varying ratios of the constituents(NbRe).Unlike other devices previously reported and made with a top-down approach,our NbRe devices systematically exhibit a GCS effect when they were fabricated from NbRe thin films with small grain size and etched in specific conditions.These observations pave the way for the realization of top-down-made GCS devices with high scalability.Our results also imply that physical parameters like structural disorder and surface physical properties of the nanobridges,which can be in turn modified by the fabrication process,are crucial for a GCS observation,providing therefore also important insights into the physics underlying the GCS effect.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB31000000)the National Natural Science Foundation of China(32170480,31972866,31702016,31601858,32022009)+5 种基金Chinese Academy of Sciences(Youth Innovation Promotion Association),Chinese Academy of Sciences(http://www.yicas.cn)the Pioneer Hundred Talents Program,and ZDBS-LYSM005)the Second Tibetan Plateau Scientific Expedition and Research Program(STEP,2019QZKK0501)State Key Laboratory of Genetic Resources and Evolution,Kunming Institute of Zoology,Chinese Academy of Sciences(GREKF21-04)the Young Top-notch Talent Cultivation Program of Hubei Provincesupported by the Wuhan Branch,Supercomputing Center,Chinese Academy of Sciences,China。
文摘The uplift of the Tibetan Plateau significantly altered the geomorphology and climate of the Euroasia by creating large mountains and rivers.Fishes are more likely to be affected relative to other organisms,as they are largely restricted to river systems.Faced with the rapidly flowing water in the Tibetan Plateau,a group of catfish has evolved greatly enlarged pectoral fins with more numbers of fin-rays to form an adhesive apparatus.However,the genetic basis of these adaptations in Tibetan catfishes remains elusive.In this study,we performed comparative genomic analyses based on the chromosome-level genome of Glyptosternum maculatum in family Sisoridae and detected some proteins with conspicuously high evolutionary rates in particular in genes involved in skeleton development,energy metabolism,and hypoxia response.We found that the hoxd12a gene evolved faster and a loss-of-function assay of hoxd12a supports a potential role for this gene in shaping the enlarged fins of these Tibetan catfishes.Other genes with amino acid replacements and signatures of positive selection included proteins involved in low temperature(TRMU)and hypoxia(VHL)responses.Functional assays reveal that the G.maculatum TRMU allele generates more mitochondrial ATP than the ancestral allele found in low-altitude fishes.Functional assays of VHL alleles suggest that the G.maculatum allele has lower transactivation activity than the low-altitude forms.These findings provide a window into the genomic underpinnings of physiological adaptations that permit G.maculatum to survive in the harsh environment of the Tibetan Himalayas that mirror those that are convergently found in other vertebrates such as humans.
基金supported by the grants from the National Institutes of Health(1R01AI101028-01A1)the Office of Health,Infectious Diseases and Nutrition in the Bureau for Global Health,U.S.Agency for International Development(GHA-G-00-06-00001)
文摘Agro-ecological conditions associated with the spread and persistence of highly pathogenic avian inlfuenza （HPAI） are not well understood, but the trade of live poultry is suspected to be a major pathway. Although market chains of live bird trade have been studied through indirect means including interviews and questionnaires, direct methods have not been used to identify movements of individual poultry. To bridge the knowledge gap on quantitative movement and transportation of poultry, we introduced a novel approach for applying telemetry to document domestic duck movements from source farms at Poyang Lake, China. We deployed recently developed transmitters that record Global Positioning System （GPS） locations and send them through the Groupe Spécial Mobile （GSM） cellular telephone system. For the ifrst time, we were able to track individually marked ducks from 3 to 396 km from their origin to other farms, distribution facilities, or live bird markets. Our proof of concept test showed that the use of GPS-GSM transmitters may provide di-rect, quantitative information to document the movement of poultry and reveal their market chains. Our ifndings provide an initial indication of the complexity of source-market network connectivity and highlight the great potential for future telemetry studies in poultry network analyses.
文摘Environmental conditions change constantly either by anthropogenic perturbation or naturally across space and time.Often,a change in behavior is the frst response to changing conditions.Behavioral fexibility can potentially improve an organism’s chances to survive and reproduce.Currently,we lack an understanding on the time-scale such behavioral adjustments need,how they actually affect reproduction and survival and whether behavioral adjustments are suffcient in keeping up with changing conditions.We used house mice(Mus musculus)to test whether personality and life-history traits can adjust to an experimentally induced food-switch fexibly in adulthood or by intergenerational plasticity,that is,adjustments only becoming visible in the offspring generation.Mice lived in 6 experimental populations of semi-natural environments either on high or standard quality food for 4 generations.We showed previously that high-quality food induced better conditions and a less risk-prone personality.Here,we tested whether the speed and/or magnitude of adjustment shows condition-dependency and whether adjustments incur ftness effects.Life-history but not personality traits reacted fexibly to a food-switch,primarily by a direct reduction of reproduction and sloweddown growth.Offspring whose parents received a food-switch developed a more active stress-coping personality and gained weight at a slower rate compared with their respective controls.Furthermore,the modulation of most traits was condition-dependent,with animals previously fed with high-quality food showing stronger responses.Our study highlights that life-history and personality traits adjust at different speed toward environmental change,thus,highlighting the importance of the environment and the mode of response for evolutionary models.
