Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via ...Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via North China, to Japan under the westerlies, and the plateau path from South Asia over the Himalayas to the northern Tibetan Plateau, are set up, based on the IAEA (International Atomic Energy Agency)/WMO global survey network and sampling sites on the Tibetan Plateau. The variations, and the relationship with precipitation and temperature, of the δ18 O in precipitation along the three cross sections are analyzed and compared. Along the south path, the seasonal differences of mean δ18O in precipitation are small at the stations located in the Tropics, but increase markedly from Bangkok towards the north, with the δ18O in the rainy season smaller than in,the dry season. The δ18O values in precipitation fluctuate on the whole, which shows that there are different vapor sources. Along the north path, the seasonal differences of the mean δ18O in precipitation for the stations in the west of Zhengzhou are all greater than in the east of Zhengzhou. During the cold half of the year, the mean δ18O in precipitation reaches its minimum at Urumqi with the lowest temperature due to the wide, cold high pressure over Mongolia, then increases gradually with longitude, and remains at roughly the same level at the stations eastward from Zhengzhou. During the warm half of the year, the δ18O values in precipitation are lower in the east than in the west, markedly influenced by the summer monsoon over East Asia. Along the plateau path, the mean δ18O values in precipitation in the rainy season are correspondingly high in the southern parts of the Indian subcontinent, and then decrease gradually with latitude. A sharp depletion of the stable isotopic compositions in precipitation takes place due to the very strong rainout of the stable isotopic compositions in vapor in the process of lifting over the southern slope of the Himalayas. The low level of the δ18O in precipitation is from Nyalam to the Tanggula Mountains during the rainy season, but δ18O increases persistently with increasing latitude from the Tanggula Mountains to the northern Tibetan Plateau because of the replenishment of vapor with relatively heavy stable isotopic compositions originating from the inner plateau. During the dry season, the mean δ18O values in precipitation basically decrease along the path from the south to the north. Generally, the mean δ18O in precipitation during the rainy season is lower than in the dry season for the regions controlled by the monsoons over South Asia or the plateau, and opposite for the regions without a monsoon or with a weak monsoon.展开更多
Heterogeneous photocatalytic reaction has been generally applied for degradation of toxic contaminants.Degradations of a compound using the same kind of catalyst that was synthesized differently are commonly found in ...Heterogeneous photocatalytic reaction has been generally applied for degradation of toxic contaminants.Degradations of a compound using the same kind of catalyst that was synthesized differently are commonly found in literature.However,the reported degradation intermediates are normally inconsistent.This issue is especially important for the degradation of toxic compounds because intermediates may be more toxic than their parent compounds and understanding the reason is necessary if appropriate catalysts are to be designed.This work systematically compares the photocatalytic degradation of diuron,a toxic recalcitrant herbicide,on two forms of zinc oxide(ZnO),i.e.,conventional particles with zinc-and oxygen-terminated polar surfaces as the dominating planes,and nanorods with mixed-terminated nonpolar surfaces.Experimental and theoretical results indicate that both the rate of reaction and the degradation pathway depend on the adsorption configuration of diuron onto the surface.Diuron molecules adsorb in different alignments on the two surfaces,contributing to the formation of different degradation intermediates.Both the aliphatic and aromatic sides of diuron adsorb on the polar surfaces simultaneously,leading to an attack by hydroxyl radicals from both ends.On the other hand,on the mixed-terminated surface,only the aliphatic part adsorbs and is degraded.The exposed surface is therefore the key factor controlling the degradation pathway.For diuron degradation on ZnO,a catalyst confined tomixed-terminated surfaces,i.e.,ZnO nanorods,is more desirable,as it avoids the formation of intermediates with potent phytotoxicity and cytogenotoxicity.展开更多
The histopathological diagnosis of gastric mucosal biopsy and endoscopic mucosal resection/endoscopic submucosal dissection specimens is important,but the diagnostic criteria,terminology,and grading system are not the...The histopathological diagnosis of gastric mucosal biopsy and endoscopic mucosal resection/endoscopic submucosal dissection specimens is important,but the diagnostic criteria,terminology,and grading system are not the same in the East and West.A structurally invasive focus is necessary to diagnose carcinoma for most Western pathologists,but Japanese pathologists make a diagnosis of cancer based on severe dysplastic cytologic atypia irrespective of the presence of invasion.Although the Vienna classification was introduced to reduce diagnostic discrepancies,it has been difficult to adopt due to different concepts for gastric epithelial neoplastic lesions.Korean pathologists experience much difficulty making a diagnosis because we are influenced by Japanese pathologists as well as Western medicine.Japan is geographically close to Korea,and academic exchanges are active.Additionally,Korean doctors are familiar with Western style medical terminology.As a result,the terminology,definitions,and diagnostic criteria for gastric intraepithelial neoplasia are very heterogeneous in Korea.To solve this problem,the Gastrointestinal Pathology Study Group of the Korean Society of Pathologists has made an effort and has suggested guidelines for differential diagnosis:(1) a diagnosis of carcinoma is based on invasion;(2) the most important characteristic of low grade dysplasia is the architectural pattern such as regular distribution of crypts without severe branching,budding,or marked glandular crowding;(3) if nuclear pseudostratification occupies more than the basal half of the cryptal cells in three or more adjacent crypts,the lesion is considered high grade dysplasia;(4) if severe cytologic atypia is present,careful inspection for invasive foci is necessary,because the risk for invasion is very high;and(5) other structural or nuclear atypia should be evaluated to make a final decision such as cribriform pattern,papillae,ridges,vesicular nuclei,high nuclear/cytoplasmic ratio,loss of nuclear polarity,thick and irregular nuclear membrane,and nucleoli.展开更多
We propose a novel shared sub-path protection (SSPP) algorithm to protect the double-link failures in wavelength division multiplexing (WDM) mesh networks. SSPP segments the primary path into several equal-length sub-...We propose a novel shared sub-path protection (SSPP) algorithm to protect the double-link failures in wavelength division multiplexing (WDM) mesh networks. SSPP segments the primary path into several equal-length sub-paths and searches two link-disjoint backup paths for each sub-path. When computing the paths, SSPP considers the load balance and the resource sharing degree, so that the blocking ratio can be effectively reduced. The simulation results show that SSPP not only can completely protect the double-link failures but also can make the tradeoffs between the resource utilization ratio (or blocking ratio) and the protection-switching time.展开更多
The combustion reaction of hydrogen with oxygen is an important reaction in hydrogen energy research and space technology. The reaction O+H2→OH+H is one of the elementary reactions of combustion. The activation energ...The combustion reaction of hydrogen with oxygen is an important reaction in hydrogen energy research and space technology. The reaction O+H2→OH+H is one of the elementary reactions of combustion. The activation energy and the minimum energy path of this reaction have been calculated by the BEBO method.展开更多
An oriented graph is a digraph in which there is no loop but exists at most one are between two vertices. An oriented graph is denoted by D = (V, A), where V is the vertex set in D, A is the arc set in D. Let D be an ...An oriented graph is a digraph in which there is no loop but exists at most one are between two vertices. An oriented graph is denoted by D = (V, A), where V is the vertex set in D, A is the arc set in D. Let D be an oriented graph such that the in-degree and out-degree of each vertex is at least k. B. Jackson proved that D contains a path of length at least 2k. In this paper, we tried to give a better result.展开更多
The COVID-19 pandemic,which was declared by the WHO,had created a global health crisis and disrupted people’s daily lives.A large number of people were affected by the COVID-19 pandemic.Therefore,a diagnostic model n...The COVID-19 pandemic,which was declared by the WHO,had created a global health crisis and disrupted people’s daily lives.A large number of people were affected by the COVID-19 pandemic.Therefore,a diagnostic model needs to be generated which can effectively classify the COVID and non-COVID cases.In this work,our aim is to develop a diagnostic model based on deep features using effectiveness of Chest X-ray(CXR)in distinguishing COVID from non-COVID cases.The proposed diagnostic framework utilizes CXR to diagnose COVID-19 and includes Grad-CAM visualizations for a visual interpretation of predicted images.The model’s performance was evaluated using various metrics,including accuracy,precision,recall,F1-score,and Gmean.Several machine learning models,such as random forest,dense neural network,SVM,twin SVM,extreme learning machine,random vector functional link,and kernel ridge regression,were selected to diagnose COVID-19 cases.Transfer learning was used to extract deep features.For feature extraction many CNN-based models such as Inception V3,MobileNet,ResNet50,VGG16 and Xception models are used.It was evident from the experiments that ResNet50 architecture outperformed all other CNN architectures based on AUC.The TWSVM classifier achieved the highest AUC score of 0.98 based on the ResNet50 feature vector.展开更多
BACKGROUND Breast cancer is a leading cause of cancer-related mortality among women worldwide,with invasive ductal carcinoma(IDC)being the most prevalent subtype.Lymph node metastasis is the primary prognostic indicat...BACKGROUND Breast cancer is a leading cause of cancer-related mortality among women worldwide,with invasive ductal carcinoma(IDC)being the most prevalent subtype.Lymph node metastasis is the primary prognostic indicator,typically evaluated via biopsy of the ipsilateral sentinel or axillary lymph nodes.Contralateral axillary metastasis(CAM)without ipsilateral involvement is exceedingly rare,particularly in early-stage breast cancer.This report presents a case of CAM in a patient with triple-negative breast cancer(TNBC),underscoring diagnostic and therapeutic complexities.CASE SUMMARY A 73-year-old female presented with left-sided early-stage IDC in February 2023.Despite a modified radical mastectomy and pathologically negative ipsilateral lymph nodes,a postoperative positron emission tomography(PET)scan detected fluorodeoxyglucose-avid nodes in the contralateral axilla.Biopsy confirmed metastatic ductal carcinoma with triple-negative status,resulting in an upstaged diagnosis of metastatic breast cancer,stage IV,M1.The patient underwent six cycles of adjuvant chemotherapy,with follow-up PET imaging showing regression of the contralateral lesion.This case highlights the importance of advanced imaging in TNBC for precise staging and treatment optimization.CONCLUSION This case highlights the aggressive nature of TNBC and the need for advanced imaging to ensure accurate staging and effective management.展开更多
基金This work was supported by the National High Technology Research and Development Program of China(863 Program,Grant No.2002AA135360)the National Natural Science Foundation of China(Grant Nos.40271025 and 90302006).
文摘Three sampling cross sections along the south path starting from the Tropics through the vapor passage in the Yunnan-Guizhou Plateau to the middle-low reaches of the Yangtze River, the north path from West China, via North China, to Japan under the westerlies, and the plateau path from South Asia over the Himalayas to the northern Tibetan Plateau, are set up, based on the IAEA (International Atomic Energy Agency)/WMO global survey network and sampling sites on the Tibetan Plateau. The variations, and the relationship with precipitation and temperature, of the δ18 O in precipitation along the three cross sections are analyzed and compared. Along the south path, the seasonal differences of mean δ18O in precipitation are small at the stations located in the Tropics, but increase markedly from Bangkok towards the north, with the δ18O in the rainy season smaller than in,the dry season. The δ18O values in precipitation fluctuate on the whole, which shows that there are different vapor sources. Along the north path, the seasonal differences of the mean δ18O in precipitation for the stations in the west of Zhengzhou are all greater than in the east of Zhengzhou. During the cold half of the year, the mean δ18O in precipitation reaches its minimum at Urumqi with the lowest temperature due to the wide, cold high pressure over Mongolia, then increases gradually with longitude, and remains at roughly the same level at the stations eastward from Zhengzhou. During the warm half of the year, the δ18O values in precipitation are lower in the east than in the west, markedly influenced by the summer monsoon over East Asia. Along the plateau path, the mean δ18O values in precipitation in the rainy season are correspondingly high in the southern parts of the Indian subcontinent, and then decrease gradually with latitude. A sharp depletion of the stable isotopic compositions in precipitation takes place due to the very strong rainout of the stable isotopic compositions in vapor in the process of lifting over the southern slope of the Himalayas. The low level of the δ18O in precipitation is from Nyalam to the Tanggula Mountains during the rainy season, but δ18O increases persistently with increasing latitude from the Tanggula Mountains to the northern Tibetan Plateau because of the replenishment of vapor with relatively heavy stable isotopic compositions originating from the inner plateau. During the dry season, the mean δ18O values in precipitation basically decrease along the path from the south to the north. Generally, the mean δ18O in precipitation during the rainy season is lower than in the dry season for the regions controlled by the monsoons over South Asia or the plateau, and opposite for the regions without a monsoon or with a weak monsoon.
基金funded by the Thailand Research Fund (No. DBG5580006)
文摘Heterogeneous photocatalytic reaction has been generally applied for degradation of toxic contaminants.Degradations of a compound using the same kind of catalyst that was synthesized differently are commonly found in literature.However,the reported degradation intermediates are normally inconsistent.This issue is especially important for the degradation of toxic compounds because intermediates may be more toxic than their parent compounds and understanding the reason is necessary if appropriate catalysts are to be designed.This work systematically compares the photocatalytic degradation of diuron,a toxic recalcitrant herbicide,on two forms of zinc oxide(ZnO),i.e.,conventional particles with zinc-and oxygen-terminated polar surfaces as the dominating planes,and nanorods with mixed-terminated nonpolar surfaces.Experimental and theoretical results indicate that both the rate of reaction and the degradation pathway depend on the adsorption configuration of diuron onto the surface.Diuron molecules adsorb in different alignments on the two surfaces,contributing to the formation of different degradation intermediates.Both the aliphatic and aromatic sides of diuron adsorb on the polar surfaces simultaneously,leading to an attack by hydroxyl radicals from both ends.On the other hand,on the mixed-terminated surface,only the aliphatic part adsorbs and is degraded.The exposed surface is therefore the key factor controlling the degradation pathway.For diuron degradation on ZnO,a catalyst confined tomixed-terminated surfaces,i.e.,ZnO nanorods,is more desirable,as it avoids the formation of intermediates with potent phytotoxicity and cytogenotoxicity.
文摘The histopathological diagnosis of gastric mucosal biopsy and endoscopic mucosal resection/endoscopic submucosal dissection specimens is important,but the diagnostic criteria,terminology,and grading system are not the same in the East and West.A structurally invasive focus is necessary to diagnose carcinoma for most Western pathologists,but Japanese pathologists make a diagnosis of cancer based on severe dysplastic cytologic atypia irrespective of the presence of invasion.Although the Vienna classification was introduced to reduce diagnostic discrepancies,it has been difficult to adopt due to different concepts for gastric epithelial neoplastic lesions.Korean pathologists experience much difficulty making a diagnosis because we are influenced by Japanese pathologists as well as Western medicine.Japan is geographically close to Korea,and academic exchanges are active.Additionally,Korean doctors are familiar with Western style medical terminology.As a result,the terminology,definitions,and diagnostic criteria for gastric intraepithelial neoplasia are very heterogeneous in Korea.To solve this problem,the Gastrointestinal Pathology Study Group of the Korean Society of Pathologists has made an effort and has suggested guidelines for differential diagnosis:(1) a diagnosis of carcinoma is based on invasion;(2) the most important characteristic of low grade dysplasia is the architectural pattern such as regular distribution of crypts without severe branching,budding,or marked glandular crowding;(3) if nuclear pseudostratification occupies more than the basal half of the cryptal cells in three or more adjacent crypts,the lesion is considered high grade dysplasia;(4) if severe cytologic atypia is present,careful inspection for invasive foci is necessary,because the risk for invasion is very high;and(5) other structural or nuclear atypia should be evaluated to make a final decision such as cribriform pattern,papillae,ridges,vesicular nuclei,high nuclear/cytoplasmic ratio,loss of nuclear polarity,thick and irregular nuclear membrane,and nucleoli.
基金This work was supported by the National Natural Science Foundation of China under Grant No. 60302010. L. Guo's email is haveball@263.net.
文摘We propose a novel shared sub-path protection (SSPP) algorithm to protect the double-link failures in wavelength division multiplexing (WDM) mesh networks. SSPP segments the primary path into several equal-length sub-paths and searches two link-disjoint backup paths for each sub-path. When computing the paths, SSPP considers the load balance and the resource sharing degree, so that the blocking ratio can be effectively reduced. The simulation results show that SSPP not only can completely protect the double-link failures but also can make the tradeoffs between the resource utilization ratio (or blocking ratio) and the protection-switching time.
文摘The combustion reaction of hydrogen with oxygen is an important reaction in hydrogen energy research and space technology. The reaction O+H2→OH+H is one of the elementary reactions of combustion. The activation energy and the minimum energy path of this reaction have been calculated by the BEBO method.
文摘An oriented graph is a digraph in which there is no loop but exists at most one are between two vertices. An oriented graph is denoted by D = (V, A), where V is the vertex set in D, A is the arc set in D. Let D be an oriented graph such that the in-degree and out-degree of each vertex is at least k. B. Jackson proved that D contains a path of length at least 2k. In this paper, we tried to give a better result.
文摘The COVID-19 pandemic,which was declared by the WHO,had created a global health crisis and disrupted people’s daily lives.A large number of people were affected by the COVID-19 pandemic.Therefore,a diagnostic model needs to be generated which can effectively classify the COVID and non-COVID cases.In this work,our aim is to develop a diagnostic model based on deep features using effectiveness of Chest X-ray(CXR)in distinguishing COVID from non-COVID cases.The proposed diagnostic framework utilizes CXR to diagnose COVID-19 and includes Grad-CAM visualizations for a visual interpretation of predicted images.The model’s performance was evaluated using various metrics,including accuracy,precision,recall,F1-score,and Gmean.Several machine learning models,such as random forest,dense neural network,SVM,twin SVM,extreme learning machine,random vector functional link,and kernel ridge regression,were selected to diagnose COVID-19 cases.Transfer learning was used to extract deep features.For feature extraction many CNN-based models such as Inception V3,MobileNet,ResNet50,VGG16 and Xception models are used.It was evident from the experiments that ResNet50 architecture outperformed all other CNN architectures based on AUC.The TWSVM classifier achieved the highest AUC score of 0.98 based on the ResNet50 feature vector.
文摘BACKGROUND Breast cancer is a leading cause of cancer-related mortality among women worldwide,with invasive ductal carcinoma(IDC)being the most prevalent subtype.Lymph node metastasis is the primary prognostic indicator,typically evaluated via biopsy of the ipsilateral sentinel or axillary lymph nodes.Contralateral axillary metastasis(CAM)without ipsilateral involvement is exceedingly rare,particularly in early-stage breast cancer.This report presents a case of CAM in a patient with triple-negative breast cancer(TNBC),underscoring diagnostic and therapeutic complexities.CASE SUMMARY A 73-year-old female presented with left-sided early-stage IDC in February 2023.Despite a modified radical mastectomy and pathologically negative ipsilateral lymph nodes,a postoperative positron emission tomography(PET)scan detected fluorodeoxyglucose-avid nodes in the contralateral axilla.Biopsy confirmed metastatic ductal carcinoma with triple-negative status,resulting in an upstaged diagnosis of metastatic breast cancer,stage IV,M1.The patient underwent six cycles of adjuvant chemotherapy,with follow-up PET imaging showing regression of the contralateral lesion.This case highlights the importance of advanced imaging in TNBC for precise staging and treatment optimization.CONCLUSION This case highlights the aggressive nature of TNBC and the need for advanced imaging to ensure accurate staging and effective management.
