Based on annual runoff data collected from several hydrological stations in the Nen River Basin from 1956 to 2004,the cumulative filter method,Mann-Kendall method and Morlet wavelet analysis were used to analyze varia...Based on annual runoff data collected from several hydrological stations in the Nen River Basin from 1956 to 2004,the cumulative filter method,Mann-Kendall method and Morlet wavelet analysis were used to analyze variations in the characteristics and factors influencing runoff.Specifically,the general characteristics list as:The distribution of runoff was found to be uneven within a year,and the annual variation showed an overall decreasing trend.The abrupt change points of runoff were found to be in the early 1960s,middle 1980s and late 1990s.Multiple time scales analysis revealed three time-scale cycles,a long-term cycle of about 20-35 years with a scale center of 25 years,another cycle of about 8-15 years with a scale center of 11 years and a short-term cycle of about 5 years.Based on the Morlet wavelet transform coefficients figure of the 25-year time scale,it is preliminarily estimated that the Nen River Basin will enter a high flow period in 2013.The results obtained using various methods were consistent with each other.The physical causes of the results were also analyzed to confirm their accuracy.展开更多
Against the current background of global climate change, the study of variations in the soil carbon pool and its controlling factors may aid in the evaluation of soil＇s role in the mitigation or enhancement of greenh...Against the current background of global climate change, the study of variations in the soil carbon pool and its controlling factors may aid in the evaluation of soil＇s role in the mitigation or enhancement of greenhouse gas. This paper studies spatial and temporal variation in the soil carbon pool and their controlling factors in the southern Song-nen Plain in Heilongjiang Province, using soil data collected over two distinct periods by the Multi-purpose Regional Geochemical Survey in 2005-2007, and another soil survey conducted in 1982-1990. The study area is a carbon source of 1479 t/km2 and in the past 20 years, from the 1980s until 2005, the practical carbon emission from the soil was 0.12 Gt. Temperature, which has been found to be linearly correlated to soil organic carbon, is the domi- nant climatologic factor controlling soil organic carbon contents. Our study shows that in the relevant area and time period the potential loss of soil organic carbon caused by rising temperatures was 0.10 Gt, the potential soil carbon emission resulting from land-use change was 0.09 Gt, and the combined potential loss of soil carbon （0.19 Gt） caused by warming and land-use change is comparable to that of fossil fuel combustion （0.21 Gt）. Due to the time delay in soil carbon pool variation, there is still 0.07 Gt in the potential emission caused by warming and land-use change that will be gradually released in the future.展开更多
Objective： The aim of the study was to analyze the clinicopathologic characteristics of gastroenteropancreatic neuroendocrine neoplasm （GEP-NEN） and to explore the prognostic factors for patients and differences of...Objective： The aim of the study was to analyze the clinicopathologic characteristics of gastroenteropancreatic neuroendocrine neoplasm （GEP-NEN） and to explore the prognostic factors for patients and differences of immunohisto- chemical markers between neuroendocrine tumor （NET） and neuroendocrine carcinoma （NEC）. Methods： Retrospective reviews were conducted for the charts of 119 patients with GEP-NEN at the Affiliated Hospital of Qingdao University （China） from August 2003 to December 2013. Kaplan-Meier method was used to do the overall survivals analysis for the patients at different levels of predictive factors. Meanwhile, Cox proportional hazard model was used to select independent risk factors of surJival. Analysis of variance was used to compare the expression of immunohistochemical markers among different patho- logical grades. Results：Among 119 patients, pancreas （45/119, 37.82%） and rectum （33/119, 27.73%） were mostly involved. The onset age of GEP-NEN in female group was younger than that of the male group. There were 13 deaths （10.92%） during 18.9 （0.1-133.4） months follow-up period. Multivariate analysis indicated that neural invasion, gender and pathological grades of NET and NEC were independent risk factors. In neuroendocrine neoplasm （NEN）, Syn expression in G2 was higher than G1 and G3, while CgA showed no significant difference. All markers showed no significant differences between NET and NEC. Conclusion： GEP-NEN may occur at multiple sites of digestive system and lack specific clinical manifestations. Syn expression detected for the prognosis of G1, G2 and G3 tumors have clinical significance. Neural invasion, sex and patho- logical grades were independent prognostic factors for GEP-NEN patients. No significant difference was found in different pathological grades of NET and NEC.展开更多
Neuroendocrine neoplasms(NENs)are highly heterogeneous and potentially malignant tumors arising from secretory cells of the neuroendocrine system.Gastroenteropancreatic NENs(GEP-NENs)are the most common subtype of NEN...Neuroendocrine neoplasms(NENs)are highly heterogeneous and potentially malignant tumors arising from secretory cells of the neuroendocrine system.Gastroenteropancreatic NENs(GEP-NENs)are the most common subtype of NENs.Historically,GEP-NENs have been regarded as infrequent and slow-growing malignancies;however,recent data have demonstrated that the worldwide prevalence and incidence of GEP-NENs have increased exponentially over the last three decades.In addition,an increasing number of studies have proven that GEP-NENs result in a limited life expectancy.These findings suggested that the natural biology of GEP-NENs is more aggressive than commonly assumed.Therefore,there is an urgent need for advanced researches focusing on the diagnosis and management of patients with GEP-NENs.In this review,we have summarized the limitations and recent advancements in our comprehension of the epidemiology,clinical presentations,pathology,molecular biology,diagnosis,and treatment of GEP-NETs to identify factors contributing to delays in diagnosis and timely treatment of these patients.展开更多
基金Natural Science Foundation of China(Grant No.51379088)Application Foundation Item of Science and Technology Department of Jilin Province(Grant No.2011-05013)
文摘Based on annual runoff data collected from several hydrological stations in the Nen River Basin from 1956 to 2004,the cumulative filter method,Mann-Kendall method and Morlet wavelet analysis were used to analyze variations in the characteristics and factors influencing runoff.Specifically,the general characteristics list as:The distribution of runoff was found to be uneven within a year,and the annual variation showed an overall decreasing trend.The abrupt change points of runoff were found to be in the early 1960s,middle 1980s and late 1990s.Multiple time scales analysis revealed three time-scale cycles,a long-term cycle of about 20-35 years with a scale center of 25 years,another cycle of about 8-15 years with a scale center of 11 years and a short-term cycle of about 5 years.Based on the Morlet wavelet transform coefficients figure of the 25-year time scale,it is preliminarily estimated that the Nen River Basin will enter a high flow period in 2013.The results obtained using various methods were consistent with each other.The physical causes of the results were also analyzed to confirm their accuracy.
基金funded by Commonweal Trade Scientific Research from the Ministry of Land and Resources of the People's Republic of China
文摘Against the current background of global climate change, the study of variations in the soil carbon pool and its controlling factors may aid in the evaluation of soil＇s role in the mitigation or enhancement of greenhouse gas. This paper studies spatial and temporal variation in the soil carbon pool and their controlling factors in the southern Song-nen Plain in Heilongjiang Province, using soil data collected over two distinct periods by the Multi-purpose Regional Geochemical Survey in 2005-2007, and another soil survey conducted in 1982-1990. The study area is a carbon source of 1479 t/km2 and in the past 20 years, from the 1980s until 2005, the practical carbon emission from the soil was 0.12 Gt. Temperature, which has been found to be linearly correlated to soil organic carbon, is the domi- nant climatologic factor controlling soil organic carbon contents. Our study shows that in the relevant area and time period the potential loss of soil organic carbon caused by rising temperatures was 0.10 Gt, the potential soil carbon emission resulting from land-use change was 0.09 Gt, and the combined potential loss of soil carbon （0.19 Gt） caused by warming and land-use change is comparable to that of fossil fuel combustion （0.21 Gt）. Due to the time delay in soil carbon pool variation, there is still 0.07 Gt in the potential emission caused by warming and land-use change that will be gradually released in the future.
文摘Objective： The aim of the study was to analyze the clinicopathologic characteristics of gastroenteropancreatic neuroendocrine neoplasm （GEP-NEN） and to explore the prognostic factors for patients and differences of immunohisto- chemical markers between neuroendocrine tumor （NET） and neuroendocrine carcinoma （NEC）. Methods： Retrospective reviews were conducted for the charts of 119 patients with GEP-NEN at the Affiliated Hospital of Qingdao University （China） from August 2003 to December 2013. Kaplan-Meier method was used to do the overall survivals analysis for the patients at different levels of predictive factors. Meanwhile, Cox proportional hazard model was used to select independent risk factors of surJival. Analysis of variance was used to compare the expression of immunohistochemical markers among different patho- logical grades. Results：Among 119 patients, pancreas （45/119, 37.82%） and rectum （33/119, 27.73%） were mostly involved. The onset age of GEP-NEN in female group was younger than that of the male group. There were 13 deaths （10.92%） during 18.9 （0.1-133.4） months follow-up period. Multivariate analysis indicated that neural invasion, gender and pathological grades of NET and NEC were independent risk factors. In neuroendocrine neoplasm （NEN）, Syn expression in G2 was higher than G1 and G3, while CgA showed no significant difference. All markers showed no significant differences between NET and NEC. Conclusion： GEP-NEN may occur at multiple sites of digestive system and lack specific clinical manifestations. Syn expression detected for the prognosis of G1, G2 and G3 tumors have clinical significance. Neural invasion, sex and patho- logical grades were independent prognostic factors for GEP-NEN patients. No significant difference was found in different pathological grades of NET and NEC.
基金supported by the National Natural Science Foundation of China(82104596)the Shenzhen Key Medical Discipline Construction Fund&Sanming Project of Medicine in Shenzhen(SZSM202111002)+1 种基金the Medicine-Engineering Interdisciplinary Research Foundation of Shenzhen University(2023YG019)the Shenzhen Science and Technology Program(GJHZ20220913143005010)。
文摘Neuroendocrine neoplasms(NENs)are highly heterogeneous and potentially malignant tumors arising from secretory cells of the neuroendocrine system.Gastroenteropancreatic NENs(GEP-NENs)are the most common subtype of NENs.Historically,GEP-NENs have been regarded as infrequent and slow-growing malignancies;however,recent data have demonstrated that the worldwide prevalence and incidence of GEP-NENs have increased exponentially over the last three decades.In addition,an increasing number of studies have proven that GEP-NENs result in a limited life expectancy.These findings suggested that the natural biology of GEP-NENs is more aggressive than commonly assumed.Therefore,there is an urgent need for advanced researches focusing on the diagnosis and management of patients with GEP-NENs.In this review,we have summarized the limitations and recent advancements in our comprehension of the epidemiology,clinical presentations,pathology,molecular biology,diagnosis,and treatment of GEP-NETs to identify factors contributing to delays in diagnosis and timely treatment of these patients.
