The identification and characterization of rock types is a core activity in geology and related fields,including mining,petroleum,environmental science,industry,and construction.Traditionally,this task is performed by...The identification and characterization of rock types is a core activity in geology and related fields,including mining,petroleum,environmental science,industry,and construction.Traditionally,this task is performed by human specialists who analyze and describe the type,composition,texture,shape,and other properties of rock samples,whether collected in-situ or prepared in a laboratory.However,the process is subjective,dependent on the specialist’s experience,and time-consuming.This study proposes an artificial intelligence-based approach that combines computer vision and natural language processing to generate both textual and verbal descriptions from images of rock thin sections.A dataset of images and corresponding textual descriptions is used to train a hybrid deep learning model.Features extracted from the images using EfficientNetB7 are processed by a Transformer network to generate textual descriptions,which are then converted into verbal responses using a speech synthesis service.The experimental results show an accuracy of 0.892 and a BLEU score of 0.71.This model offers potential utility for research,professional,and academic applications and has been deployed as a web application for public use.展开更多
Tissue clearing combined with high-resolution confocal imaging is a cutting-edge approach for dissecting the three-dimensional(3D)architecture of tissues and deciphering cellular spatial interactions under physiologic...Tissue clearing combined with high-resolution confocal imaging is a cutting-edge approach for dissecting the three-dimensional(3D)architecture of tissues and deciphering cellular spatial interactions under physiological and pathological conditions.Deciphering the spatial interaction of leptin receptor-expressing(LepR^(+))stromal cells with other compartments in the bone marrow is crucial for a deeper understanding of the stem cell niche and the skeletal tissue.In this study,we introduce an optimized protocol for the 3D analysis of skeletal tissues,enabling the visualization of hematopoietic and stromal cells,especially LepR+stromal cells,within optically cleared bone hemisections.Our method preserves the 3D tissue architecture and is extendable to other hematopoietic sites such as calvaria and vertebrae.The protocol entails tissue fixation,decalcification,and cryosectioning to reveal the marrow cavity.Completed within approximately 12 days,this process yields highly transparent tissues that maintain genetically encoded or antibody-stained fluorescent signals.The bone hemisections are compatible with diverse antibody labeling strategies.Confocal microscopy of these transparent samples allows for qualitative and quantitative image analysis using Aivia or Bitplane Imaris software,assessing a spectrum of parameters.With proper storage,the fluorescent signal in the stained and cleared bone hemisections remains intact for at least 2–3 months.This protocol is robust,straightforward to implement,and highly reproducible,offering a valuable tool for tissue architecture and cellular interaction studies.展开更多
Here,we report the spin-orbit state-resolved differential cross sections(DCSs)for the prototype barrierless reaction S(^(1)D)+HD.Both product channels,namely H+SD(^(2)Π_(3/2,1/2))and D+SH(^(2)Π_(3/2,1/2)),were measu...Here,we report the spin-orbit state-resolved differential cross sections(DCSs)for the prototype barrierless reaction S(^(1)D)+HD.Both product channels,namely H+SD(^(2)Π_(3/2,1/2))and D+SH(^(2)Π_(3/2,1/2)),were measured by high-resolution crossed molecular beam experiments.The DCSs of the two product channels show an overall forward-backward symmetry,in accordance with statistical model predictions.However,the DCSs for different spin-orbit manifolds show different preferences in forward or backward scattering directions at the same collision energies.This study reveals that,even though the title reaction proceeds via the long-lived complex mechanism,the spin-orbit coupling effects in the product channels play an important role in the reaction process.展开更多
Inelastic collisions are the dominant cause of energy loss in radiotherapy.In the energy range around the Bragg peak,single ionization(SI)and single-electron capture(SC)are the primary inelastic collisions that lead t...Inelastic collisions are the dominant cause of energy loss in radiotherapy.In the energy range around the Bragg peak,single ionization(SI)and single-electron capture(SC)are the primary inelastic collisions that lead to energy loss.This study employs the classical trajectory Monte Carlo method to study the SI and SC processes of H_(2)O molecules using He^(2+) and C^(6+) projectiles in the energy range of 10 keV/u to 10 MeV/u.The total cross sections,single differential cross sections,impact parameter dependence of SI and SC,and fragmentation cross sections were investigated.Results illustrate that the cross section for SI is the highest when the projectile energy is close to the Bragg peak energy.When the projectile energy is below the Bragg peak energy,the ionized electrons in the forward direction dominate,and the removal of electrons can be associated with large impact parameters.As the projectile energy increases,the emission angle of the electrons gradually transitions from small angles(60°~120°)to large angles(60°~120°),and the removal of electrons is associated with small impact parameters.The energy distributions of the ionized electron are similar when the projectile energy is equal to,below or above the Bragg peak energy.The fragmentation cross sections after SI and SC in the energy range around the Bragg peak were also estimated.展开更多
To overcome the limitations of low efficiency and reliance on manual processes in the measurement of geometric parameters for bridge prefabricated components,a method based on deep learning and computer vision is deve...To overcome the limitations of low efficiency and reliance on manual processes in the measurement of geometric parameters for bridge prefabricated components,a method based on deep learning and computer vision is developed to identify the geometric parameters.The study utilizes a common precast element for highway bridges as the research subject.First,edge feature points of the bridge component section are extracted from images of the precast component cross-sections by combining the Canny operator with mathematical morphology.Subsequently,a deep learning model is developed to identify the geometric parameters of the precast components using the extracted edge coordinates from the images as input and the predefined control parameters of the bridge section as output.A dataset is generated by varying the control parameters and noise levels for model training.Finally,field measurements are conducted to validate the accuracy of the developed method.The results indicate that the developed method effectively identifies the geometric parameters of bridge precast components,with an error rate maintained within 5%.展开更多
Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan r...Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology.展开更多
The protection of classical or significant reference stratigraphic sections of the nation’s valuable geoheritage has become a priority by the Chinese government and national stratigraphic commission.The process for t...The protection of classical or significant reference stratigraphic sections of the nation’s valuable geoheritage has become a priority by the Chinese government and national stratigraphic commission.The process for the protection and documentation of stratigraphic sections includes:(1)marked tablets showing the standardized bed,member and formation divisions and,where applicable,standardized meter intervals for future investigations;(2)a monument or other on-site interpretive information;and(3)field guides for different audiences summarizing its importance with maps and detailed descriptions.In particular,the ten Global Stratotype Sections and Points(GSSPs)established in southern China are well preserved and managed;and some are now within tourist-friendly educational national geoparks.We suggest that other national stratigraphic commissions might incorporate some of the experiences from China’s current efforts to preserve and standardize important reference sections for Earth history research.展开更多
[Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and ...[Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and a new method termed＆quot;opening a window on cornea and refixation＆quot; was used to prepare paraffin sections for cattle eyebal s in the treatment group. [Result] After the prepared specimens in the treatment group were fixed, it could be macroscopical y observed that retina and choroid were closely connected, with detachment occurring at a smal portion be-tween the two. According to the paraffin sections, it was microscopical y observed that the continuity of trabecular meshwork was intact, as wel as the continuity be-tween different layers of eyebal wal , without detachment between them, no retinal detachment, no shrinkage of each layer of tissue cells. [Conclusion] This study pro-vides a foundation for the basic research and pathological study of eyebal s.展开更多
Convolutional neural networks have been widely used for analyzing image data in industry,especially in the oil and gas area.Brazil has an extensive hydrocarbon reserve on its coast and has also benefited from these ne...Convolutional neural networks have been widely used for analyzing image data in industry,especially in the oil and gas area.Brazil has an extensive hydrocarbon reserve on its coast and has also benefited from these neural network models.Image data from petrographic thin section can be essential to provide information about reservoir quality,highlighting important features such as carbonate lithology.However,the automatic identification of lithology in reservoir rocks is still a significant challenge,mainly due to the heterogeneity that is part of the lithologies of the Brazilian pre-salt.Within this context,this work presents an approach using one-class or specialist models to identify four classes of lithology present in reservoir rocks in the Brazilian pre-salt.The proposed methodology had the challenge of dealing with a small number of images for training the neural networks,in addition to the complexity involved in the analyzed data.An auto-machine learning tool called AutoKeras was used to define the hyperparameters of the implemented models.The results found were satisfactory and presented an accuracy greater than 70%for image samples belonging to other wells not seen during the model building,which increases the applicability of the implemented model.Finally,a comparison was made between the proposed methodology and multiple-class models,demonstrating the superiority of one-class models.展开更多
The direct and dissociative ionizations of oxygen molecule are investigated experimen-tally by electron collision with energies from 350 eV to 8000 eV.The absolute ionization cross sections for the product ions(O_(2)^...The direct and dissociative ionizations of oxygen molecule are investigated experimen-tally by electron collision with energies from 350 eV to 8000 eV.The absolute ionization cross sections for the product ions(O_(2)^(2+),O_(2)^(2+)O^(+),O^(2+),and their total)and two Coulomb explosion channels(O^(+)+O^(+)and O^(2+)+O^(+))are obtained by putting the data of O^(2+)on the scale of Ar+from O_(2)and Ar gases mixed with a fixed relative flow ratio of 1:1.The experimental errors are assessed by taking uncertainties of various factors into account.The present absolute cross sections are well consistent with the previous data in the overlapped energy range below 1000 eV.展开更多
The neutron capture cross section for^(165)Ho was measured at the backstreaming white neutron beam line(Back-n)of the China Spallation Neutron Source(CSNS)using total energy detection systems,composed of a set of four...The neutron capture cross section for^(165)Ho was measured at the backstreaming white neutron beam line(Back-n)of the China Spallation Neutron Source(CSNS)using total energy detection systems,composed of a set of four C_(6)D_(6)scintillator detectors coupled with pulse height weighting techniques.The resonance parameters were extracted using the multilevel multichannel R-matrix code SAMMY to fit the measured capture yields of the^(165)Ho(n,γ)reaction in the neutron energy range below100 eV.Subsequently,the resonance region’s capture cross sections were reconstructed based on the obtained parameters.Furthermore,the unresolved resonance average cross section of the^(165)Ho(n,γ)reaction was determined relative to that of the standard sample^(197)Au within the neutron energy range of 2 keV to 1 MeV.The experimental data were compared with the recommended nuclear data from the ENDF/B-VIII.0 library,as well as with results of calculations performed using the TALYS-1.9 code.The comparison revealed agreement between the measured^(165)Ho(n,γ)cross sections and these data.The present results are crucial for evaluating the^(165)Ho neutron capture cross section and thus enhance the quality of evaluated nuclear data libraries.They provide valuable guidance for nuclear theoretical models and nuclear astrophysical studies.展开更多
The neutron capture cross sections(n,γ)of bromine were obtained using the time-of-flight technique at the Back-n facility of the China Spallation Neutron Source.Promptγ-rays originating from neutron-induced capture ...The neutron capture cross sections(n,γ)of bromine were obtained using the time-of-flight technique at the Back-n facility of the China Spallation Neutron Source.Promptγ-rays originating from neutron-induced capture events were detected using four C_(6)D_(6) detectors.The pulse-height weighting technique and double-bunch unfolding method based on Bayesian theory were used in the data analysis.Background deductions,normalization,and corrections were carefully considered to obtain reliable measurement results.The multilevel R-matrix Bayesian code SAMMY was used to extract the resonance parameters in the resolved resonance region(RRR).The average cross sections in the unresolved resonance region(URR)were obtained from 10 to 400 keV.The experimental results were compared with data from several evaluated libraries and previous experi-ments in the RRR and URR.The TALYS code was used to describe the average cross sections in the URR.The astrophysical Maxwell average cross sections(MACSs)of ^(79,81)Br from kT=5 to 100 keV were calculated over a sufficiently wide range of neutron energies.At a thermal energy of kT=30 keV,the MACS value for ^(79)Br 682±68 mb was in good agreement with the KADoNiS v1.0 recommended value.By contrast,the value of 293±29 mb for ^(81)Br was substantially higher than that of the evaluated database and the KADoNiS v1.0 recommended value.展开更多
The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in th...The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in the Basque Country,northern Spain.In the hemipelagic section exposed at Zumaia the base of the Selandian Stage has been placed at the base of the Itzurun Formation,ca.49 m above the Cretaceous/Paleogene boundary.At the base of the Selandian,marls replace the succession of Danian red limestone and limestone-marl couplets.The best marine,global correlation criterion for the basal Selandian is the second radiation of the important calcareous nannofossil group.展开更多
AIM:To compare the performance of three commercially available anti-human epidermalgrowth factor receptor 2(HER2)antibodies in whole-tissue sections and tissue microarrays(TMAs)of a series of gastric tumors.METHODS:We...AIM:To compare the performance of three commercially available anti-human epidermalgrowth factor receptor 2(HER2)antibodies in whole-tissue sections and tissue microarrays(TMAs)of a series of gastric tumors.METHODS:We present a comparative analysis of three anti-HER2 antibodies(HercepTest,4B5 and SP3)using TMA and whole-tissue sections prepared from the same paraffin blocks of 199 gastric adenocarcinomas operated upon between January 2004 and December2008 at a Brazilian cancer hospital.The data on the patients’age,sex,the anatomical location of the tumor and the Lauren’s histological classification were collected from clinical and pathological records.The immunohistochemical(IHC)results were examined by two pathologists and the cases were classified as positive(3+),equivocal(2+)and negative(0 or 1+),according to the criteria of the IHC scoring system of gastric cancer.TMAs and whole-tissue sections were evaluated separately and independently.All cases yielding discordant IHC results and/or scored as 2+were subjected to dual-color in situ hybridization in order to determine the final HER2 status.Besides determining the sensitivity and predictive value for HER2-positive status,we measured the accuracy of each antibody by calculating the area under the receiver operating characteristic(ROC)curve.The agreement between the results obtained using the TMAs and those obtained using the whole-tissue sections was assessed by means of Kappa coefficient.RESULTS:Intratumoral heterogeneity of HER2 expression was observed with all antibodies.HER2-positive expression(3+)in the whole-tissue sections was observed in 23 cases(11.6%)using the 4B5 antibody,in 18 cases(9.1%)using the SP3 antibody and in 10 cases(5.1%)using the HercepTest antibody.In the TMAs,11 positive cases(5.6%)were identified using SP3 antibody,9(4.6%)using the 4B5 antibody and 6(3%)using the HercepTest antibody.The sensitivity using whole-tissue sections and TMA,respectively,was 95.2%and 42.9%with 4B5,90.5%and 66.7%with SP3 and 47.6%and42.9%with HercepTest.The accuracy,calculated from the area under the ROC curve,using whole-tissue sections and TMA,respectively,was 0.91 and 0.79 by 4B5,0.86 and 0.80 by SP3 and 0.73 and 0.71 by HercepTest.The concordance of the results obtained using wholetissue sections and TMA was 97.4%(Kappa 0.75)using HercepTest,85.6%(Kappa 0.56)using SP3 and 84.1%(Kappa 0.38)using 4B5.CONCLUSION:The use of the 4B5 antibody on wholetissue sections was the most accurate IHC method for evaluating HER2 expression in gastric adenocarcinoma.展开更多
This paper describes a new method for simulation of the cross section shape of log. The self-developed MQK3102 log shape recognizing machine was used to acquire the finite discrete sampling points on the cross section...This paper describes a new method for simulation of the cross section shape of log. The self-developed MQK3102 log shape recognizing machine was used to acquire the finite discrete sampling points on the cross section of log and those points were fitted with the quadratic B-spline parametric curve. This method can clearly stimulate the real shape of the log cross section and is characterized by limited sampling points and high speed computing. The computed result of the previous curve does not affect the next one, which may avoid the graphic distortion caused by the accumulative error. The method can be used to simulate the whole body shape of log approximately by sampling the cross sections along the length direction of log, thus providing a reference model for optimum saw cutting of log.展开更多
A new anisotropic potential is fitted to ab initio data. The close-coupling approach is utilized to calculate state-tostate rotational excitation partial wave cross sections for elastic and inelastic collisions of He ...A new anisotropic potential is fitted to ab initio data. The close-coupling approach is utilized to calculate state-tostate rotational excitation partial wave cross sections for elastic and inelastic collisions of He atom with HBr molecule based on the fitted potential. The calculation is performed separately at the incident energies： 75, 100 and 200 meV.The tendency of the elastic and inelastic rotational excitation partial wave cross sections varying with total angular quantum number J is obtained.展开更多
This work is an attempt to improve the Bayesian neural network (BNN) for studying photoneutron yield cross sections as a function of the charge number Z, mass number A, and incident energy ε. The BNN was improved in ...This work is an attempt to improve the Bayesian neural network (BNN) for studying photoneutron yield cross sections as a function of the charge number Z, mass number A, and incident energy ε. The BNN was improved in terms of three aspects:numerical parameters, input layer, and network structure. First, by minimizing the deviations between the predictions and data, the numerical parameters, including the hidden layer number, hidden node number, and activation function, were selected. It was found that the BNN with three hidden layers, 10 hidden nodes, and sigmoid activation function provided the smallest deviations. Second, based on known knowledge,such as the isospin dependence and shape effect, the optimal ground-state properties were selected as input neurons. Third, the Lorentzian function was applied to map the hidden nodes to the output cross sections, and the empirical formula of the Lorentzian parameters was applied to link some of the input nodes to the output cross sections. It was found that the last two aspects improved the predictions and avoided overfitting, especially for the axially deformed nucleus.展开更多
Normal mammalian secondary palate development undergoes a series of processes,including palatal shelf(PS)growth,elevation,adhesion and fusion,and palatal bone formation.It has been estimated that more than 90%of isola...Normal mammalian secondary palate development undergoes a series of processes,including palatal shelf(PS)growth,elevation,adhesion and fusion,and palatal bone formation.It has been estimated that more than 90%of isolated cleft palate is caused by defects associated with the elevation process.However,because of the rapidly completed elevation process,the entire process of elevation will never be easy to clarify.In this article,we present a novel method for three-dimensional(3D)reconstruction of thick tissue blocks from two-dimensional(2D)histological sections.We established multiplanar sections of the palate and tongue in coronal and sagittal directions,and further performed 3D reconstruction to observe the morphological interaction and connection between the two components prior to and during elevation.The method completes an imaging system for simultaneous morphological analysis of thick tissue samples using both synthetic and real data.The new method will provide a comprehensive picture of reorientation morphology and gene expression pattern during the palatal elevation process.展开更多
It has been repeatedly observed that the mechanical properties of microtomed wood sections are significantly lower than those of samples of normal size, but few investigations have been conducted to deal with this top...It has been repeatedly observed that the mechanical properties of microtomed wood sections are significantly lower than those of samples of normal size, but few investigations have been conducted to deal with this topic, especially based on theoretical approaches. We measured the longitudinal MOE of Chinese fir on microtomed sections ranging in thickness from 70 to 200 μm and compared these with the values of samples of normal size. The results indicate that the MOE of microtomed wood sections increases with thickness from 70 to 200 μm, but is significantly less than that of normal samples. A size effect coefficient of 2.63 is inferred based on statistical data for samples of normal size and 200 μm thick microtomed sections. Finally, an explanation based on a complete shear restraint model of cell walls and a single fiber multi-ply model is proposed for the size effect on stiffness of microtomed wood sections.展开更多
A lead-shielded HPGe detector and offlineγ-ray spectra of the residual product were used to measure the cross section(CS)and ratios of isomeric CS(σm/σg)in^(134)Xe(n,2n)^(133m),gXe reactions at different energies(1...A lead-shielded HPGe detector and offlineγ-ray spectra of the residual product were used to measure the cross section(CS)and ratios of isomeric CS(σm/σg)in^(134)Xe(n,2n)^(133m),gXe reactions at different energies(13.5 MeV,13.8 MeV,14.1 MeV,14.4 MeV,14.8 MeV)relative to the^(93)Nb(n,2n)^(92)mNb reaction CS.The target was high-purity natural Xe gas under high pressure.The T(d,n)4He reaction produces neutrons.TALYS code(version 1.95)for nuclear reactions was used for calculations,with default parameters and nuclear level density models.The uncertainties in the measured CS data were thoroughly analyzed using the covariance analysis method.The results were compared with theoretical values,evaluation data,and previous experimental findings.CS data of the 134Xe(n,2n)133mXe and 134Xe(n,2n)133gXe reactions and the corresponding isomeric CS ratios at 13.5 MeV,13.8 MeV,and 14.1 MeV neutron energies are reported for the first time.This research advances our knowledge of pre-equilibrium emission in the(n,2n)reaction channel by resolving inconsistencies in the Xe data.展开更多
文摘The identification and characterization of rock types is a core activity in geology and related fields,including mining,petroleum,environmental science,industry,and construction.Traditionally,this task is performed by human specialists who analyze and describe the type,composition,texture,shape,and other properties of rock samples,whether collected in-situ or prepared in a laboratory.However,the process is subjective,dependent on the specialist’s experience,and time-consuming.This study proposes an artificial intelligence-based approach that combines computer vision and natural language processing to generate both textual and verbal descriptions from images of rock thin sections.A dataset of images and corresponding textual descriptions is used to train a hybrid deep learning model.Features extracted from the images using EfficientNetB7 are processed by a Transformer network to generate textual descriptions,which are then converted into verbal responses using a speech synthesis service.The experimental results show an accuracy of 0.892 and a BLEU score of 0.71.This model offers potential utility for research,professional,and academic applications and has been deployed as a web application for public use.
基金National Natural Science Foundation of China(grant number 82272563 to B.S.)National Science and Technology Major Project of the Ministry of Science and Technology of China(grant number 2023ZD0501202 to B.S.)+4 种基金institutional grants allocated to the National Institute of Biological Sciences,Beijing(NIBS)from the Chinese Ministry of Science and Technology,Beijing Municipal Commission of Science and Technology,and Tsinghua Universitythe support from China Pharmaceutical University(grant number 3150140001 to S.F.)National Natural Science Foundation of China(grant numbers 82203653 to S.F.,82371957 to L.W.,and 82371956 to X.C.)Beijing Municipal Public Welfare Development and Reform Pilot Project for Medical Research Institutes(grant number JYY2023-8 to X.C.)Research Grants Council of University Grants Committee Hong Kong(grant numbers 14113723,14108720,14121721,14202920,N_CUHK472/22,C7030-18G,T13-402/17-N,and AoE/M-402/20)。
文摘Tissue clearing combined with high-resolution confocal imaging is a cutting-edge approach for dissecting the three-dimensional(3D)architecture of tissues and deciphering cellular spatial interactions under physiological and pathological conditions.Deciphering the spatial interaction of leptin receptor-expressing(LepR^(+))stromal cells with other compartments in the bone marrow is crucial for a deeper understanding of the stem cell niche and the skeletal tissue.In this study,we introduce an optimized protocol for the 3D analysis of skeletal tissues,enabling the visualization of hematopoietic and stromal cells,especially LepR+stromal cells,within optically cleared bone hemisections.Our method preserves the 3D tissue architecture and is extendable to other hematopoietic sites such as calvaria and vertebrae.The protocol entails tissue fixation,decalcification,and cryosectioning to reveal the marrow cavity.Completed within approximately 12 days,this process yields highly transparent tissues that maintain genetically encoded or antibody-stained fluorescent signals.The bone hemisections are compatible with diverse antibody labeling strategies.Confocal microscopy of these transparent samples allows for qualitative and quantitative image analysis using Aivia or Bitplane Imaris software,assessing a spectrum of parameters.With proper storage,the fluorescent signal in the stained and cleared bone hemisections remains intact for at least 2–3 months.This protocol is robust,straightforward to implement,and highly reproducible,offering a valuable tool for tissue architecture and cellular interaction studies.
基金supported by the National Natural Science Foundation of China(Nos.92476207,22288201)the Chinese Academy of Sciences(No.XBD0970202)+2 种基金the Innovation Program for Quantum Science and Technology(No.2021ZD0303300)the Shenzhen Science and Technology Innovation Committee(No.20220814164755002)the Guangdong Innovative&Entrepreneurial Research Team Program(Nos.2019ZT08L455,2019JC01X091).
文摘Here,we report the spin-orbit state-resolved differential cross sections(DCSs)for the prototype barrierless reaction S(^(1)D)+HD.Both product channels,namely H+SD(^(2)Π_(3/2,1/2))and D+SH(^(2)Π_(3/2,1/2)),were measured by high-resolution crossed molecular beam experiments.The DCSs of the two product channels show an overall forward-backward symmetry,in accordance with statistical model predictions.However,the DCSs for different spin-orbit manifolds show different preferences in forward or backward scattering directions at the same collision energies.This study reveals that,even though the title reaction proceeds via the long-lived complex mechanism,the spin-orbit coupling effects in the product channels play an important role in the reaction process.
基金supported in part by the National Natural Science Foundation of China(Nos.12105327 and 11775108)the Hunan Provincial Innovation Foundation For Postgraduate(No.QL20220210)the Advanced Energy Science and Technology Guangdong Laboratory.
文摘Inelastic collisions are the dominant cause of energy loss in radiotherapy.In the energy range around the Bragg peak,single ionization(SI)and single-electron capture(SC)are the primary inelastic collisions that lead to energy loss.This study employs the classical trajectory Monte Carlo method to study the SI and SC processes of H_(2)O molecules using He^(2+) and C^(6+) projectiles in the energy range of 10 keV/u to 10 MeV/u.The total cross sections,single differential cross sections,impact parameter dependence of SI and SC,and fragmentation cross sections were investigated.Results illustrate that the cross section for SI is the highest when the projectile energy is close to the Bragg peak energy.When the projectile energy is below the Bragg peak energy,the ionized electrons in the forward direction dominate,and the removal of electrons can be associated with large impact parameters.As the projectile energy increases,the emission angle of the electrons gradually transitions from small angles(60°~120°)to large angles(60°~120°),and the removal of electrons is associated with small impact parameters.The energy distributions of the ionized electron are similar when the projectile energy is equal to,below or above the Bragg peak energy.The fragmentation cross sections after SI and SC in the energy range around the Bragg peak were also estimated.
基金The National Natural Science Foundation of China(No.52338011,52378291)Young Elite Scientists Sponsorship Program by CAST(No.2022-2024QNRC0101).
文摘To overcome the limitations of low efficiency and reliance on manual processes in the measurement of geometric parameters for bridge prefabricated components,a method based on deep learning and computer vision is developed to identify the geometric parameters.The study utilizes a common precast element for highway bridges as the research subject.First,edge feature points of the bridge component section are extracted from images of the precast component cross-sections by combining the Canny operator with mathematical morphology.Subsequently,a deep learning model is developed to identify the geometric parameters of the precast components using the extracted edge coordinates from the images as input and the predefined control parameters of the bridge section as output.A dataset is generated by varying the control parameters and noise levels for model training.Finally,field measurements are conducted to validate the accuracy of the developed method.The results indicate that the developed method effectively identifies the geometric parameters of bridge precast components,with an error rate maintained within 5%.
文摘Taking state-controlled section of Xuzhou Peiyan river as an example,the current water quality was monitored,and the cause of over water quality standard was analyzed.The results showed that the pollutants of Peiyan river were mainly from the urban river segment,and the immediate cause of over standard was tributary pollutants in urban river segment with the runoff into rivers.So we should strengthen the maintenance of drainage control and gate-han,accelerate the construction of urban wastewater treatment facilities and supporting pipe network,promote rural decentralized sewage treatment,prevent and control livestock and poultry pollution,pesticides and fertilizers pollution,and intercept non-point source pollution by using eco-technology.
文摘The protection of classical or significant reference stratigraphic sections of the nation’s valuable geoheritage has become a priority by the Chinese government and national stratigraphic commission.The process for the protection and documentation of stratigraphic sections includes:(1)marked tablets showing the standardized bed,member and formation divisions and,where applicable,standardized meter intervals for future investigations;(2)a monument or other on-site interpretive information;and(3)field guides for different audiences summarizing its importance with maps and detailed descriptions.In particular,the ten Global Stratotype Sections and Points(GSSPs)established in southern China are well preserved and managed;and some are now within tourist-friendly educational national geoparks.We suggest that other national stratigraphic commissions might incorporate some of the experiences from China’s current efforts to preserve and standardize important reference sections for Earth history research.
基金Supported by China Agriculture Research System(CARS-38)~~
文摘[Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and a new method termed＆quot;opening a window on cornea and refixation＆quot; was used to prepare paraffin sections for cattle eyebal s in the treatment group. [Result] After the prepared specimens in the treatment group were fixed, it could be macroscopical y observed that retina and choroid were closely connected, with detachment occurring at a smal portion be-tween the two. According to the paraffin sections, it was microscopical y observed that the continuity of trabecular meshwork was intact, as wel as the continuity be-tween different layers of eyebal wal , without detachment between them, no retinal detachment, no shrinkage of each layer of tissue cells. [Conclusion] This study pro-vides a foundation for the basic research and pathological study of eyebal s.
基金supported by the R&D cooperation agreement be-tween Petrobras and CBPF(Contract No.0050.0121790.22.9)Brazilian Research Council(CNPq)for the scholarships for students.
文摘Convolutional neural networks have been widely used for analyzing image data in industry,especially in the oil and gas area.Brazil has an extensive hydrocarbon reserve on its coast and has also benefited from these neural network models.Image data from petrographic thin section can be essential to provide information about reservoir quality,highlighting important features such as carbonate lithology.However,the automatic identification of lithology in reservoir rocks is still a significant challenge,mainly due to the heterogeneity that is part of the lithologies of the Brazilian pre-salt.Within this context,this work presents an approach using one-class or specialist models to identify four classes of lithology present in reservoir rocks in the Brazilian pre-salt.The proposed methodology had the challenge of dealing with a small number of images for training the neural networks,in addition to the complexity involved in the analyzed data.An auto-machine learning tool called AutoKeras was used to define the hyperparameters of the implemented models.The results found were satisfactory and presented an accuracy greater than 70%for image samples belonging to other wells not seen during the model building,which increases the applicability of the implemented model.Finally,a comparison was made between the proposed methodology and multiple-class models,demonstrating the superiority of one-class models.
基金supported by the National Key Research and Development Program of China(No.2022YFA1602502)the National Natural Science Foundation of China(No.12127804).
文摘The direct and dissociative ionizations of oxygen molecule are investigated experimen-tally by electron collision with energies from 350 eV to 8000 eV.The absolute ionization cross sections for the product ions(O_(2)^(2+),O_(2)^(2+)O^(+),O^(2+),and their total)and two Coulomb explosion channels(O^(+)+O^(+)and O^(2+)+O^(+))are obtained by putting the data of O^(2+)on the scale of Ar+from O_(2)and Ar gases mixed with a fixed relative flow ratio of 1:1.The experimental errors are assessed by taking uncertainties of various factors into account.The present absolute cross sections are well consistent with the previous data in the overlapped energy range below 1000 eV.
基金supported by the National Natural Science Foundation of China(Nos.12465024,12365018,U2032146)Inner Mongolia National Science Foundation(Nos.2024ZD23,2024FX30,2023MS01005)+1 种基金Program for Innovative Research Team in Universities of Inner Mongolia Autonomous Region(NMGIRT2217)Program for Young Talents of Science and Technology in Universities of Inner Mongolia Autonomous Region(NJYT23109)。
文摘The neutron capture cross section for^(165)Ho was measured at the backstreaming white neutron beam line(Back-n)of the China Spallation Neutron Source(CSNS)using total energy detection systems,composed of a set of four C_(6)D_(6)scintillator detectors coupled with pulse height weighting techniques.The resonance parameters were extracted using the multilevel multichannel R-matrix code SAMMY to fit the measured capture yields of the^(165)Ho(n,γ)reaction in the neutron energy range below100 eV.Subsequently,the resonance region’s capture cross sections were reconstructed based on the obtained parameters.Furthermore,the unresolved resonance average cross section of the^(165)Ho(n,γ)reaction was determined relative to that of the standard sample^(197)Au within the neutron energy range of 2 keV to 1 MeV.The experimental data were compared with the recommended nuclear data from the ENDF/B-VIII.0 library,as well as with results of calculations performed using the TALYS-1.9 code.The comparison revealed agreement between the measured^(165)Ho(n,γ)cross sections and these data.The present results are crucial for evaluating the^(165)Ho neutron capture cross section and thus enhance the quality of evaluated nuclear data libraries.They provide valuable guidance for nuclear theoretical models and nuclear astrophysical studies.
基金This work was supported by the National Natural Science Foundation of China(Nos.U1832182,11875328,11761161001,and U2032137)the Natural Science Foundation of Guangdong Province,China(Nos.18zxxt65 and 2022A1515011184)+3 种基金the Science and Technology Development Fund,Macao SAR(Grant No.008/2017/AFJ)the Macao Young Scholars Program of China(No.AM201907)the China Postdoctoral Science Foundation(Nos.2016LH0045 and 2017M621573)the Fundamental Research Funds for the Central Universities(Nos.22qntd3101 and 2021qntd28).
文摘The neutron capture cross sections(n,γ)of bromine were obtained using the time-of-flight technique at the Back-n facility of the China Spallation Neutron Source.Promptγ-rays originating from neutron-induced capture events were detected using four C_(6)D_(6) detectors.The pulse-height weighting technique and double-bunch unfolding method based on Bayesian theory were used in the data analysis.Background deductions,normalization,and corrections were carefully considered to obtain reliable measurement results.The multilevel R-matrix Bayesian code SAMMY was used to extract the resonance parameters in the resolved resonance region(RRR).The average cross sections in the unresolved resonance region(URR)were obtained from 10 to 400 keV.The experimental results were compared with data from several evaluated libraries and previous experi-ments in the RRR and URR.The TALYS code was used to describe the average cross sections in the URR.The astrophysical Maxwell average cross sections(MACSs)of ^(79,81)Br from kT=5 to 100 keV were calculated over a sufficiently wide range of neutron energies.At a thermal energy of kT=30 keV,the MACS value for ^(79)Br 682±68 mb was in good agreement with the KADoNiS v1.0 recommended value.By contrast,the value of 293±29 mb for ^(81)Br was substantially higher than that of the evaluated database and the KADoNiS v1.0 recommended value.
文摘The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in the Basque Country,northern Spain.In the hemipelagic section exposed at Zumaia the base of the Selandian Stage has been placed at the base of the Itzurun Formation,ca.49 m above the Cretaceous/Paleogene boundary.At the base of the Selandian,marls replace the succession of Danian red limestone and limestone-marl couplets.The best marine,global correlation criterion for the basal Selandian is the second radiation of the important calcareous nannofossil group.
文摘AIM:To compare the performance of three commercially available anti-human epidermalgrowth factor receptor 2(HER2)antibodies in whole-tissue sections and tissue microarrays(TMAs)of a series of gastric tumors.METHODS:We present a comparative analysis of three anti-HER2 antibodies(HercepTest,4B5 and SP3)using TMA and whole-tissue sections prepared from the same paraffin blocks of 199 gastric adenocarcinomas operated upon between January 2004 and December2008 at a Brazilian cancer hospital.The data on the patients’age,sex,the anatomical location of the tumor and the Lauren’s histological classification were collected from clinical and pathological records.The immunohistochemical(IHC)results were examined by two pathologists and the cases were classified as positive(3+),equivocal(2+)and negative(0 or 1+),according to the criteria of the IHC scoring system of gastric cancer.TMAs and whole-tissue sections were evaluated separately and independently.All cases yielding discordant IHC results and/or scored as 2+were subjected to dual-color in situ hybridization in order to determine the final HER2 status.Besides determining the sensitivity and predictive value for HER2-positive status,we measured the accuracy of each antibody by calculating the area under the receiver operating characteristic(ROC)curve.The agreement between the results obtained using the TMAs and those obtained using the whole-tissue sections was assessed by means of Kappa coefficient.RESULTS:Intratumoral heterogeneity of HER2 expression was observed with all antibodies.HER2-positive expression(3+)in the whole-tissue sections was observed in 23 cases(11.6%)using the 4B5 antibody,in 18 cases(9.1%)using the SP3 antibody and in 10 cases(5.1%)using the HercepTest antibody.In the TMAs,11 positive cases(5.6%)were identified using SP3 antibody,9(4.6%)using the 4B5 antibody and 6(3%)using the HercepTest antibody.The sensitivity using whole-tissue sections and TMA,respectively,was 95.2%and 42.9%with 4B5,90.5%and 66.7%with SP3 and 47.6%and42.9%with HercepTest.The accuracy,calculated from the area under the ROC curve,using whole-tissue sections and TMA,respectively,was 0.91 and 0.79 by 4B5,0.86 and 0.80 by SP3 and 0.73 and 0.71 by HercepTest.The concordance of the results obtained using wholetissue sections and TMA was 97.4%(Kappa 0.75)using HercepTest,85.6%(Kappa 0.56)using SP3 and 84.1%(Kappa 0.38)using 4B5.CONCLUSION:The use of the 4B5 antibody on wholetissue sections was the most accurate IHC method for evaluating HER2 expression in gastric adenocarcinoma.
基金The research is supported by Project of National Natural Science Foundation of China(30571455)and National "948" Project(2005-4-62)
文摘This paper describes a new method for simulation of the cross section shape of log. The self-developed MQK3102 log shape recognizing machine was used to acquire the finite discrete sampling points on the cross section of log and those points were fitted with the quadratic B-spline parametric curve. This method can clearly stimulate the real shape of the log cross section and is characterized by limited sampling points and high speed computing. The computed result of the previous curve does not affect the next one, which may avoid the graphic distortion caused by the accumulative error. The method can be used to simulate the whole body shape of log approximately by sampling the cross sections along the length direction of log, thus providing a reference model for optimum saw cutting of log.
基金Project supported by the National Natural Science Foundation of China （Grant Nos 10574096,10676025） and the Natural Science Foundation of Education Bureau of Anhui Province, China.
文摘A new anisotropic potential is fitted to ab initio data. The close-coupling approach is utilized to calculate state-tostate rotational excitation partial wave cross sections for elastic and inelastic collisions of He atom with HBr molecule based on the fitted potential. The calculation is performed separately at the incident energies： 75, 100 and 200 meV.The tendency of the elastic and inelastic rotational excitation partial wave cross sections varying with total angular quantum number J is obtained.
基金supported by the National Natural Science Foundation of China(Nos.11905018 and 11875328).
文摘This work is an attempt to improve the Bayesian neural network (BNN) for studying photoneutron yield cross sections as a function of the charge number Z, mass number A, and incident energy ε. The BNN was improved in terms of three aspects:numerical parameters, input layer, and network structure. First, by minimizing the deviations between the predictions and data, the numerical parameters, including the hidden layer number, hidden node number, and activation function, were selected. It was found that the BNN with three hidden layers, 10 hidden nodes, and sigmoid activation function provided the smallest deviations. Second, based on known knowledge,such as the isospin dependence and shape effect, the optimal ground-state properties were selected as input neurons. Third, the Lorentzian function was applied to map the hidden nodes to the output cross sections, and the empirical formula of the Lorentzian parameters was applied to link some of the input nodes to the output cross sections. It was found that the last two aspects improved the predictions and avoided overfitting, especially for the axially deformed nucleus.
基金National Natural Science Foundation of China(81400494)the Key Program of Science&Technology Department of Sichuan Province,China(2019ZDYF1658,and 2019ZDYF1430).
文摘Normal mammalian secondary palate development undergoes a series of processes,including palatal shelf(PS)growth,elevation,adhesion and fusion,and palatal bone formation.It has been estimated that more than 90%of isolated cleft palate is caused by defects associated with the elevation process.However,because of the rapidly completed elevation process,the entire process of elevation will never be easy to clarify.In this article,we present a novel method for three-dimensional(3D)reconstruction of thick tissue blocks from two-dimensional(2D)histological sections.We established multiplanar sections of the palate and tongue in coronal and sagittal directions,and further performed 3D reconstruction to observe the morphological interaction and connection between the two components prior to and during elevation.The method completes an imaging system for simultaneous morphological analysis of thick tissue samples using both synthetic and real data.The new method will provide a comprehensive picture of reorientation morphology and gene expression pattern during the palatal elevation process.
基金the National Natural Science Foundation of China (Grant No. 30730076 and 30400337) for financial support
文摘It has been repeatedly observed that the mechanical properties of microtomed wood sections are significantly lower than those of samples of normal size, but few investigations have been conducted to deal with this topic, especially based on theoretical approaches. We measured the longitudinal MOE of Chinese fir on microtomed sections ranging in thickness from 70 to 200 μm and compared these with the values of samples of normal size. The results indicate that the MOE of microtomed wood sections increases with thickness from 70 to 200 μm, but is significantly less than that of normal samples. A size effect coefficient of 2.63 is inferred based on statistical data for samples of normal size and 200 μm thick microtomed sections. Finally, an explanation based on a complete shear restraint model of cell walls and a single fiber multi-ply model is proposed for the size effect on stiffness of microtomed wood sections.
基金supported by the National Natural science Foundation of China(Nos.11875016,12165006).
文摘A lead-shielded HPGe detector and offlineγ-ray spectra of the residual product were used to measure the cross section(CS)and ratios of isomeric CS(σm/σg)in^(134)Xe(n,2n)^(133m),gXe reactions at different energies(13.5 MeV,13.8 MeV,14.1 MeV,14.4 MeV,14.8 MeV)relative to the^(93)Nb(n,2n)^(92)mNb reaction CS.The target was high-purity natural Xe gas under high pressure.The T(d,n)4He reaction produces neutrons.TALYS code(version 1.95)for nuclear reactions was used for calculations,with default parameters and nuclear level density models.The uncertainties in the measured CS data were thoroughly analyzed using the covariance analysis method.The results were compared with theoretical values,evaluation data,and previous experimental findings.CS data of the 134Xe(n,2n)133mXe and 134Xe(n,2n)133gXe reactions and the corresponding isomeric CS ratios at 13.5 MeV,13.8 MeV,and 14.1 MeV neutron energies are reported for the first time.This research advances our knowledge of pre-equilibrium emission in the(n,2n)reaction channel by resolving inconsistencies in the Xe data.
