Construction of infectious clones by full-length cDNA is basic and key for recovering RNA virus and is core of reverse genetics.In this article,basic consideration and key technology were viewed and factors affecting ...Construction of infectious clones by full-length cDNA is basic and key for recovering RNA virus and is core of reverse genetics.In this article,basic consideration and key technology were viewed and factors affecting infectivity of clones were also summarized.Some research advances were briefly introduced about positive-strand RNA viruses infectious clones.Finally,this article also reviewed the application of infectious clones.展开更多
A detailed investigation on 3D spatial distribution rules of Banded Iron-bearing Formation(BIF) with methods of gravity-magnetic inversion and 3D modeling of iron mine is presented based on the former analysis in the ...A detailed investigation on 3D spatial distribution rules of Banded Iron-bearing Formation(BIF) with methods of gravity-magnetic inversion and 3D modeling of iron mine is presented based on the former analysis in the Anshan-Benxi area.Three dimension spatial distribution types of BIF are concluded as hook-like,tabularlike and "W"-like.BIF was mainly developed in three types of space including(1) the syncline cores,(2)cover coverage area,and(3) the deeper buried area where the range of tectonic uplift is small.The influences of tectonism,magmatic intrusion and uplift-erosion on the spatial distribution shapes of BIF are clarified.展开更多
To change the undesirable present situation of recovering and using converter gas in steel plants in China, the basic approaches to improving the converter gas recovery rate were analyzed theoretically along with the ...To change the undesirable present situation of recovering and using converter gas in steel plants in China, the basic approaches to improving the converter gas recovery rate were analyzed theoretically along with the change curves of the converter gas component content, based on the converter gas recovery system of Baosteel No. 2 steel- making plant. The effects of converter device, raw material, air imbibed quantity, recovery restricted condition, and intensity of oxygen blowing on the converter gas recovery rate were studied. Among these, the effects of the air im bibed quantity, recovery restricted condition, and intensity of oxygen blowing are remarkable. Comprehensive measures were put forward for improving the converter gas recovery from the point of devices, etc. , and good results were achieved.展开更多
This study investigates the impact of various factors on the lifespan and diagnostic time of HIV/AIDS patients using advanced statistical techniques. The Power Chris-Jerry (PCJ) distribution is applied to model CD4 co...This study investigates the impact of various factors on the lifespan and diagnostic time of HIV/AIDS patients using advanced statistical techniques. The Power Chris-Jerry (PCJ) distribution is applied to model CD4 counts of patients, and the goodness-of-fit test confirms a strong fit with a p-value of 0.6196. The PCJ distribution is found to be the best fit based on information criteria (AIC and BIC) with the smallest negative log-likelihood, AIC, and BIC values. The study uses datasets from St. Luke hospital Uyo, Nigeria, containing HIV/AIDS diagnosis date, age, CD4 count, gender, and opportunistic infection dates. Multiple linear regression is employed to analyze the relationship between these variables and HIV/AIDS diagnostic time. The results indicate that age, CD4 count, and opportunistic infection significantly impact the diagnostic time, while gender shows a nonsignificant relationship. The F-test confirms the model's overall significance, indicating the factors are good predictors of HIV/AIDS diagnostic time. The R-squared value of approximately 72% suggests that administering antiretroviral therapy (ART) can improve diagnostic time by suppressing the virus and protecting the immune system. Cox proportional hazard modeling is used to examine the effects of predictor variables on patient survival time. Age and CD4 count are not significant factors in the hazard of HIV/AIDS diagnostic time, while opportunistic infection is a significant predictor with a decreasing effect on the hazard rate. Gender shows a strong but nonsignificant relationship with decreased risk of death. To address the violation of the assumption of proportional hazard, the study employs an assumption-free alternative, Aalen’s model. In the Aalen model, all predictor variables except age and gender are statistically significant in relation to HIV/AIDS diagnostic time. The findings provide valuable insights into the factors influencing diagnostic time and survival of HIV/AIDS patients, which can inform interventions aimed at reducing transmission and improving early diagnosis and treatment. The Power Chris-Jerry distribution proves to be a suitable fit for modeling CD4 counts, while multiple linear regression and survival analysis techniques provide insights into the relationships between predictor variables and diagnostic time. These results contribute to the understanding of HIV/AIDS patient outcomes and can guide public health interventions to enhance early detection, treatment, and care.展开更多
This study investigates the impact of various factors on the lifespan and diagnostic time of HIV/AIDS patients using advanced statistical techniques. The Power Chris-Jerry (PCJ) distribution is applied to model CD4 co...This study investigates the impact of various factors on the lifespan and diagnostic time of HIV/AIDS patients using advanced statistical techniques. The Power Chris-Jerry (PCJ) distribution is applied to model CD4 counts of patients, and the goodness-of-fit test confirms a strong fit with a p-value of 0.6196. The PCJ distribution is found to be the best fit based on information criteria (AIC and BIC) with the smallest negative log-likelihood, AIC, and BIC values. The study uses datasets from St. Luke hospital Uyo, Nigeria, containing HIV/AIDS diagnosis date, age, CD4 count, gender, and opportunistic infection dates. Multiple linear regression is employed to analyze the relationship between these variables and HIV/AIDS diagnostic time. The results indicate that age, CD4 count, and opportunistic infection significantly impact the diagnostic time, while gender shows a nonsignificant relationship. The F-test confirms the model's overall significance, indicating the factors are good predictors of HIV/AIDS diagnostic time. The R-squared value of approximately 72% suggests that administering antiretroviral therapy (ART) can improve diagnostic time by suppressing the virus and protecting the immune system. Cox proportional hazard modeling is used to examine the effects of predictor variables on patient survival time. Age and CD4 count are not significant factors in the hazard of HIV/AIDS diagnostic time, while opportunistic infection is a significant predictor with a decreasing effect on the hazard rate. Gender shows a strong but nonsignificant relationship with decreased risk of death. To address the violation of the assumption of proportional hazard, the study employs an assumption-free alternative, Aalen’s model. In the Aalen model, all predictor variables except age and gender are statistically significant in relation to HIV/AIDS diagnostic time. The findings provide valuable insights into the factors influencing diagnostic time and survival of HIV/AIDS patients, which can inform interventions aimed at reducing transmission and improving early diagnosis and treatment. The Power Chris-Jerry distribution proves to be a suitable fit for modeling CD4 counts, while multiple linear regression and survival analysis techniques provide insights into the relationships between predictor variables and diagnostic time. These results contribute to the understanding of HIV/AIDS patient outcomes and can guide public health interventions to enhance early detection, treatment, and care.展开更多
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele...Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter.展开更多
Based on field survey, the thesis analyzes the key factors affecting development of rural tourism systematically, taking Chengdu as an example. These factors include regional e-conomic development level & leisure ...Based on field survey, the thesis analyzes the key factors affecting development of rural tourism systematically, taking Chengdu as an example. These factors include regional e-conomic development level & leisure tradition, tourist market & traffic, tourist resource, spatial agglomeration and competition of rural tourism, and decision-making behavior. Among them, regional economic development level & leisure tradition and tourist market & traffic are prerequisites for the development of rural tourism which have an impact on tourist' s consumption level, consumption custom, operator's investment ability, tourist destination distribution and scale; Tourist resource, spatial agglomeration and competition of rural tourism are restrictive conditions affecting character and distribution of rural tourism; Government's decision-making behavior is of importance for expansion of scale and popularity of regional rural tourism, meanwhile, operators' decision-making behavior includes investment scale and operational strategies, and for operators from the outside, location selection is included additionally. All these decision-making behaviors are subjective conditions for the development of rural tourism.展开更多
The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the...The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the nanocomposites of Chinese fir （Cunningharnia lanceolata） wood and montmorillonite （MMT） were prepared via three impregnation methods, i.e. normal pressure, once and twice vacuum methods. Based on the weight percent gain （WPG） of impregnated wood, the effects of compounding wood and MMT in terms of concentration, impregnating temperature and time, wood moisture content and wood extraction treatments, on sapwood and heartwood are discussed. Results show that： 1） the optimum MMT concentration in the impregnation solution is 3% for sapwood and 5% for heartwood; 2） room temperature is suitable in practice; 3） treatment pressure should be set at a high enough value in order to ensure sufficient permeation; 4） the effects of different impregnation methods on sapwood and heartwood are different, the heartwood extractives affect WPG significantly; cell wall permeability of sapwood is better than that of heartwood; 5） the cold water, hot water and benzene-ethanol solution extractions can all greatly improve the permeability of heartwood, hot water can dissolve some hemicellulose of low aggregation and hot water extraction improves wood cell wall permeability; 6） with an increase in wood moisture content, the permeable space in wood is reduced, but with a certain amount of water, instantaneous spaces are created and the permeation dynamic increases. This effect is especially apparent for difficult impregnating situations in heartwood and impregnation under normal pressure.展开更多
Field harvest loss is a common problem of maize grain mechanical harvesting in China and abroad.From 2012 to 2019,2987 groups of samples for the quality of mechanical grain harvesting in field were obtained in 21 majo...Field harvest loss is a common problem of maize grain mechanical harvesting in China and abroad.From 2012 to 2019,2987 groups of samples for the quality of mechanical grain harvesting in field were obtained in 21 major maize-producing provinces,cities,and regions of China.The analysis performed in this study showed that the average harvest loss of fallen ears was equivalent to 76.5%of the total harvest loss,indicating that the harvest loss in the mechanical harvesting of maize grain mainly came from the loss of fallen ears.Meanwhile,statistical analysis of the harvest loss in different ranges of grain moisture contents showed that,when the grain moisture content fell below 20%,the harvest loss rate of fallen ears and the total harvest loss rate both increased sharply,and the harvest loss of fallen ears increased faster than the harvest loss of fallen grain with a decreasing grain moisture content.Moreover,the results of multi-point experiments and harvest experiments in different periods showed that,during harvesting time,the harvest loss of fallen ears caused by lodging was the main reason for in-field harvest losses in the mechanical harvesting of maize grain.Apart from the above mentioned,the test results of 35 groups of harvesters for the in-field mechanical harvesting of maize grain showed that the harvester types and their operating parameters were important factors affecting the harvest loss in the mechanical harvesting of maize grain.Therefore,the principal paths to reduce harvest loss in the mechanical harvesting of maize grain are to breed lodging-resistant maize varieties,adopt reasonable planting densities,cultivate healthy plants,develop harvesters with low harvesting loss,intensify the training of operators,and harvest at an appropriate time.展开更多
From December 1987 to October 1983, percutaneous transluminal coronary angioplasty (PTCA) was performed in 302 patients with 392 diseased vessels and 440 lesions. The success rate was 93.71% in 302 patients, 94.90% in...From December 1987 to October 1983, percutaneous transluminal coronary angioplasty (PTCA) was performed in 302 patients with 392 diseased vessels and 440 lesions. The success rate was 93.71% in 302 patients, 94.90% in 392 diseased vessels and 95.00% in 440 lesions. The success rate was 98.92% in Type A lesion, 95.71% in Type B lesion, and 86.57% in Type C lesion (A vs B P=NS, A vs C P<0.01). There were 55 lesions with total or subtotal occlusion, the success rate was 89.09% (93.10% in Type B lesion and 84.62% in Type C lesion). As to the diseased vessels, the success rate was 95.65% in LAD, 94.38% in LCX and 93.75% in RCA. The results showed no significant difference. In this series, acute ischemic complications were found in 6.59% (29 / 440). Of these 29 lesions, 23 were treated successfully, 5 developed Q wave myocardial infarction and 1 died.展开更多
Generation of single-sideband （SSB） multi-carrier source based on a recirculating frequency shifter （RFS） is anal- ysed theoretically and realized experimentally. The effects of affecting factors originating from ...Generation of single-sideband （SSB） multi-carrier source based on a recirculating frequency shifter （RFS） is anal- ysed theoretically and realized experimentally. The effects of affecting factors originating from the deviation from the right operation bias voltage and unbalanced amplitude, and the phase of the radio frequency （RF） drive signals on the performance of the multi-tone source are discussed in detail. Based on the theoretical analysis, high-quality 50-tone out- put is successfully realized. Experiments under some implementation imperfections are also carried out. The imperfect and low-quality output results are in good agreement with theoretical analysis.展开更多
The characteristics of temporal and spatial distribution of tropical cyclone frequencies over the South China Sea areas and its affecting factors in the past 50yrs are analyzed based on typhoon data that provided by C...The characteristics of temporal and spatial distribution of tropical cyclone frequencies over the South China Sea areas and its affecting factors in the past 50yrs are analyzed based on typhoon data that provided by CMA and Simple Ocean Data Assimilation （SODA）. The results show that the tropical cyclone frequencies from June to October show concentrated geographic distribution, for they mainIy distribute over the SCS area from 15 - 20°N. The characteristics present significant interdecadal changes. The impact of oceanic factors on the tropical cyclone frequencies in the SCS area is mainly realized by La Nina and La Nifia-like events before 1975 but mainly by E1 Nino and E1 Nifio-like events after 1975.展开更多
This paper analyzes the factors that affect Intellectual Property Right(IPR) development by leveraging the way of system engineering.With scale and relationship as the objects of study,this paper explores the relation...This paper analyzes the factors that affect Intellectual Property Right(IPR) development by leveraging the way of system engineering.With scale and relationship as the objects of study,this paper explores the relationships among different factors by way of modeling,summarizes the superficial,shallow and deep reasons at different layers that affect enterprise intellectual property rights,and makes clear the correlation among all factors.展开更多
Factors affecting equipment maintenance quality usually include personnel,equipment and facilities,raw materials and spare parts, craft, environment and quality management. These six factors affecting maintenance qual...Factors affecting equipment maintenance quality usually include personnel,equipment and facilities,raw materials and spare parts, craft, environment and quality management. These six factors affecting maintenance quality are not all the same degree. In order to find out which factor can influence equipment maintenance quality greatly and achieve sophisticated management,characteristic quantities of six factors are presented. A structural equation modeling( SEM) is designed using the six factors as latent variables and their characteristic quantities as the observed variable.According to the basic data obtained from the questionnaire survey,calculate the standardized regression weight by parameter estimation of the SEM. Then the key factors affecting the quality of the equipment maintenance are determined with the help of the standardized regression weight.展开更多
Following improvements in evidential thinking,more questions have been raised about the probative values of criminal investigation records;therefore,there is an urgent need to investigate the prominent problems with t...Following improvements in evidential thinking,more questions have been raised about the probative values of criminal investigation records;therefore,there is an urgent need to investigate the prominent problems with this system for keeping investigation notes and evidence.The binding 2013 Criminal Procedural Law of the People’s Republic of China lists the victim’s statement,defendant’s confession or defence,inspection,examination,identification,and investigation notes as statutory evidence.Technically,these criminal investigation records are naturally legally admissible as evidenced in criminal justice procedures.However,the Miranda rules of the United States,which guarantee the defendant’s right to silence,have not been established in China's Mainland.Consequently,the objectivity of those kinds of criminal investigation records can be questioned during cross‑examination.Comparative and systematic research methods were used to examine the probative values and their affecting factors in criminal investigation records.The results show that it is not easy to obtain the full probative value of criminal investigation records because it involves analyses of issues such as understanding the notes,procedures,and methods in making the records,as well as the reform of related systems,such as transplanting the Miranda rules to secure the defendant’s right to silence and the presence of counsel.Only in this way can we expect evidence used in criminal investigation records to be used scientifically by ensuring that evidence of criminal acts are kept free from irrational contamination and resolve the existing related problems in judicial practice.展开更多
In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When...In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.展开更多
The gatekeeper policy has been implemented for approximately ten years on a pilot population in China. It is necessary to assess the satisfaction of patients utilizing community health service（CHS） under the gatekee...The gatekeeper policy has been implemented for approximately ten years on a pilot population in China. It is necessary to assess the satisfaction of patients utilizing community health service（CHS） under the gatekeeper system. Our study showed that the cognition of gatekeeper policy was associated with four dimensions including doctor‐patient relationships, information and support, organization of care, and accessibility（P 〈 0.001）. One or more factors such as gender and self‐perceived health scores also affected their satisfaction. General practitioners must be prepared to focus on these aspects of information and support, organization of care, and accessibility as indicators of potential opportunities for improvement. Additionally, policymakers can improve patients＇ satisfaction with CHS by strengthening their awareness of the gatekeeper policy.展开更多
The effects of prestrain and annealing temperature on phase transformation temperatures in Fel4Mn5Si8Cr4Ni shape memory alloy have been studied. The results showed that when the annealing temperature was 673 K, both t...The effects of prestrain and annealing temperature on phase transformation temperatures in Fel4Mn5Si8Cr4Ni shape memory alloy have been studied. The results showed that when the annealing temperature was 673 K, both the At and the Ms temperatures increased appreciably as the prestrain increased, the As temperature increased slightly with increasing prestrain; the resistivity difference at 303 K between the heating and cooling curve also increased with increasing prestrain, which agreed with the recovery strain. The shape memory effect in Fe-Mn-Si-Cr-Ni shape memory alloy is caused by the stress-induced γ→ε martensite transformation and its reverse transformation. When the prestrain was 10%, the Ms temperature decreased remarkably as the annealing temperature increased.展开更多
BACKGROUND: Assessing and evaluating mental health status can provide educational planners valuable information to predict the quality of physicians' performance at work. These data can help physicians to practice...BACKGROUND: Assessing and evaluating mental health status can provide educational planners valuable information to predict the quality of physicians' performance at work. These data can help physicians to practice in the most desired way. The study aimed to evaluate factors affecting psychological morbidity in Iranian emergency medicine practitioners at educational hospitals of Tehran.METHODS: In this cross sectional study 204 participants(emergency medicine residents and specialists) from educational hospitals of Tehran were recruited and their psychological morbidity was assessed by using a 28-question Goldberg General Health Questionnaire(GHQ-28). Somatization, anxiety and sleep disorders, social dysfunction and depression were evaluated among practitioners and compared to demographic and job related variables.RESULTS: Two hundreds and four participants consisting of 146(71.6%) males and 58(28.4%) females were evaluated. Of all participants, 55(27%) were single and 149(73%) were married. Most of our participants(40.2%) were between 30–35 years old. By using GHQ-28, 129(63.2%) were recognized as normal and 75(36.8%) suffered some mental health disorders. There was a signifi cant gender difference between normal practitioners and practitioners with disorder(P=0.02) while marital status had no significant difference(P=0.2). Only 19(9.3%) declared having some major mental health issue in the previous month.CONCLUSION: Females encountered more mental health disorders than male(P=0.02) and the most common disorder observed was somatization(P=0.006).展开更多
Coal mining with ploughs is an ideal coal mining technology for thin and thinner coal seams. The existence conditions of coal seams are different for each other, which affects coal mining with ploughs to different deg...Coal mining with ploughs is an ideal coal mining technology for thin and thinner coal seams. The existence conditions of coal seams are different for each other, which affects coal mining with ploughs to different degrees, and the application results are also different. The authors analyze the affecting factors by means of mathematical methods. The research is useful to the wide application of ploughs.展开更多
文摘Construction of infectious clones by full-length cDNA is basic and key for recovering RNA virus and is core of reverse genetics.In this article,basic consideration and key technology were viewed and factors affecting infectivity of clones were also summarized.Some research advances were briefly introduced about positive-strand RNA viruses infectious clones.Finally,this article also reviewed the application of infectious clones.
文摘A detailed investigation on 3D spatial distribution rules of Banded Iron-bearing Formation(BIF) with methods of gravity-magnetic inversion and 3D modeling of iron mine is presented based on the former analysis in the Anshan-Benxi area.Three dimension spatial distribution types of BIF are concluded as hook-like,tabularlike and "W"-like.BIF was mainly developed in three types of space including(1) the syncline cores,(2)cover coverage area,and(3) the deeper buried area where the range of tectonic uplift is small.The influences of tectonism,magmatic intrusion and uplift-erosion on the spatial distribution shapes of BIF are clarified.
基金Item Sponsored by National Natural Science Foundation of China (50334020)
文摘To change the undesirable present situation of recovering and using converter gas in steel plants in China, the basic approaches to improving the converter gas recovery rate were analyzed theoretically along with the change curves of the converter gas component content, based on the converter gas recovery system of Baosteel No. 2 steel- making plant. The effects of converter device, raw material, air imbibed quantity, recovery restricted condition, and intensity of oxygen blowing on the converter gas recovery rate were studied. Among these, the effects of the air im bibed quantity, recovery restricted condition, and intensity of oxygen blowing are remarkable. Comprehensive measures were put forward for improving the converter gas recovery from the point of devices, etc. , and good results were achieved.
文摘This study investigates the impact of various factors on the lifespan and diagnostic time of HIV/AIDS patients using advanced statistical techniques. The Power Chris-Jerry (PCJ) distribution is applied to model CD4 counts of patients, and the goodness-of-fit test confirms a strong fit with a p-value of 0.6196. The PCJ distribution is found to be the best fit based on information criteria (AIC and BIC) with the smallest negative log-likelihood, AIC, and BIC values. The study uses datasets from St. Luke hospital Uyo, Nigeria, containing HIV/AIDS diagnosis date, age, CD4 count, gender, and opportunistic infection dates. Multiple linear regression is employed to analyze the relationship between these variables and HIV/AIDS diagnostic time. The results indicate that age, CD4 count, and opportunistic infection significantly impact the diagnostic time, while gender shows a nonsignificant relationship. The F-test confirms the model's overall significance, indicating the factors are good predictors of HIV/AIDS diagnostic time. The R-squared value of approximately 72% suggests that administering antiretroviral therapy (ART) can improve diagnostic time by suppressing the virus and protecting the immune system. Cox proportional hazard modeling is used to examine the effects of predictor variables on patient survival time. Age and CD4 count are not significant factors in the hazard of HIV/AIDS diagnostic time, while opportunistic infection is a significant predictor with a decreasing effect on the hazard rate. Gender shows a strong but nonsignificant relationship with decreased risk of death. To address the violation of the assumption of proportional hazard, the study employs an assumption-free alternative, Aalen’s model. In the Aalen model, all predictor variables except age and gender are statistically significant in relation to HIV/AIDS diagnostic time. The findings provide valuable insights into the factors influencing diagnostic time and survival of HIV/AIDS patients, which can inform interventions aimed at reducing transmission and improving early diagnosis and treatment. The Power Chris-Jerry distribution proves to be a suitable fit for modeling CD4 counts, while multiple linear regression and survival analysis techniques provide insights into the relationships between predictor variables and diagnostic time. These results contribute to the understanding of HIV/AIDS patient outcomes and can guide public health interventions to enhance early detection, treatment, and care.
文摘This study investigates the impact of various factors on the lifespan and diagnostic time of HIV/AIDS patients using advanced statistical techniques. The Power Chris-Jerry (PCJ) distribution is applied to model CD4 counts of patients, and the goodness-of-fit test confirms a strong fit with a p-value of 0.6196. The PCJ distribution is found to be the best fit based on information criteria (AIC and BIC) with the smallest negative log-likelihood, AIC, and BIC values. The study uses datasets from St. Luke hospital Uyo, Nigeria, containing HIV/AIDS diagnosis date, age, CD4 count, gender, and opportunistic infection dates. Multiple linear regression is employed to analyze the relationship between these variables and HIV/AIDS diagnostic time. The results indicate that age, CD4 count, and opportunistic infection significantly impact the diagnostic time, while gender shows a nonsignificant relationship. The F-test confirms the model's overall significance, indicating the factors are good predictors of HIV/AIDS diagnostic time. The R-squared value of approximately 72% suggests that administering antiretroviral therapy (ART) can improve diagnostic time by suppressing the virus and protecting the immune system. Cox proportional hazard modeling is used to examine the effects of predictor variables on patient survival time. Age and CD4 count are not significant factors in the hazard of HIV/AIDS diagnostic time, while opportunistic infection is a significant predictor with a decreasing effect on the hazard rate. Gender shows a strong but nonsignificant relationship with decreased risk of death. To address the violation of the assumption of proportional hazard, the study employs an assumption-free alternative, Aalen’s model. In the Aalen model, all predictor variables except age and gender are statistically significant in relation to HIV/AIDS diagnostic time. The findings provide valuable insights into the factors influencing diagnostic time and survival of HIV/AIDS patients, which can inform interventions aimed at reducing transmission and improving early diagnosis and treatment. The Power Chris-Jerry distribution proves to be a suitable fit for modeling CD4 counts, while multiple linear regression and survival analysis techniques provide insights into the relationships between predictor variables and diagnostic time. These results contribute to the understanding of HIV/AIDS patient outcomes and can guide public health interventions to enhance early detection, treatment, and care.
基金Supported by a Sub-project "Ecological Geochemical Survey of Oil Crop (sunflower) Producing Area in Western Jilin" of the Project of China Geological Survey and Jilin Provincial Government " Agricul-tural Geological Survey of Jilin Province"~~
文摘Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter.
基金Supported by the 10th Five-Year Plan Programme Item of Chengdu Philosophy and Social Science Research and the Knowledge Innovation Program of Chinese Academy of Sciences(KZCX2-SW-319-4)
文摘Based on field survey, the thesis analyzes the key factors affecting development of rural tourism systematically, taking Chengdu as an example. These factors include regional e-conomic development level & leisure tradition, tourist market & traffic, tourist resource, spatial agglomeration and competition of rural tourism, and decision-making behavior. Among them, regional economic development level & leisure tradition and tourist market & traffic are prerequisites for the development of rural tourism which have an impact on tourist' s consumption level, consumption custom, operator's investment ability, tourist destination distribution and scale; Tourist resource, spatial agglomeration and competition of rural tourism are restrictive conditions affecting character and distribution of rural tourism; Government's decision-making behavior is of importance for expansion of scale and popularity of regional rural tourism, meanwhile, operators' decision-making behavior includes investment scale and operational strategies, and for operators from the outside, location selection is included additionally. All these decision-making behaviors are subjective conditions for the development of rural tourism.
基金This study was financially supported by the National Natural Science Foundation of China （Grant No. 30271055）.
文摘The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the nanocomposites of Chinese fir （Cunningharnia lanceolata） wood and montmorillonite （MMT） were prepared via three impregnation methods, i.e. normal pressure, once and twice vacuum methods. Based on the weight percent gain （WPG） of impregnated wood, the effects of compounding wood and MMT in terms of concentration, impregnating temperature and time, wood moisture content and wood extraction treatments, on sapwood and heartwood are discussed. Results show that： 1） the optimum MMT concentration in the impregnation solution is 3% for sapwood and 5% for heartwood; 2） room temperature is suitable in practice; 3） treatment pressure should be set at a high enough value in order to ensure sufficient permeation; 4） the effects of different impregnation methods on sapwood and heartwood are different, the heartwood extractives affect WPG significantly; cell wall permeability of sapwood is better than that of heartwood; 5） the cold water, hot water and benzene-ethanol solution extractions can all greatly improve the permeability of heartwood, hot water can dissolve some hemicellulose of low aggregation and hot water extraction improves wood cell wall permeability; 6） with an increase in wood moisture content, the permeable space in wood is reduced, but with a certain amount of water, instantaneous spaces are created and the permeation dynamic increases. This effect is especially apparent for difficult impregnating situations in heartwood and impregnation under normal pressure.
基金This work was financially supported by the National Key Research and Development Program of China(Grant No.2016YFD0300101,No.2016YFD0300110)the National Natural Science Foundation of China(Grant No.31371575)+1 种基金the China Agriculture Research System(CARS-02-25)the Agricultural Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences.
文摘Field harvest loss is a common problem of maize grain mechanical harvesting in China and abroad.From 2012 to 2019,2987 groups of samples for the quality of mechanical grain harvesting in field were obtained in 21 major maize-producing provinces,cities,and regions of China.The analysis performed in this study showed that the average harvest loss of fallen ears was equivalent to 76.5%of the total harvest loss,indicating that the harvest loss in the mechanical harvesting of maize grain mainly came from the loss of fallen ears.Meanwhile,statistical analysis of the harvest loss in different ranges of grain moisture contents showed that,when the grain moisture content fell below 20%,the harvest loss rate of fallen ears and the total harvest loss rate both increased sharply,and the harvest loss of fallen ears increased faster than the harvest loss of fallen grain with a decreasing grain moisture content.Moreover,the results of multi-point experiments and harvest experiments in different periods showed that,during harvesting time,the harvest loss of fallen ears caused by lodging was the main reason for in-field harvest losses in the mechanical harvesting of maize grain.Apart from the above mentioned,the test results of 35 groups of harvesters for the in-field mechanical harvesting of maize grain showed that the harvester types and their operating parameters were important factors affecting the harvest loss in the mechanical harvesting of maize grain.Therefore,the principal paths to reduce harvest loss in the mechanical harvesting of maize grain are to breed lodging-resistant maize varieties,adopt reasonable planting densities,cultivate healthy plants,develop harvesters with low harvesting loss,intensify the training of operators,and harvest at an appropriate time.
文摘From December 1987 to October 1983, percutaneous transluminal coronary angioplasty (PTCA) was performed in 302 patients with 392 diseased vessels and 440 lesions. The success rate was 93.71% in 302 patients, 94.90% in 392 diseased vessels and 95.00% in 440 lesions. The success rate was 98.92% in Type A lesion, 95.71% in Type B lesion, and 86.57% in Type C lesion (A vs B P=NS, A vs C P<0.01). There were 55 lesions with total or subtotal occlusion, the success rate was 89.09% (93.10% in Type B lesion and 84.62% in Type C lesion). As to the diseased vessels, the success rate was 95.65% in LAD, 94.38% in LCX and 93.75% in RCA. The results showed no significant difference. In this series, acute ischemic complications were found in 6.59% (29 / 440). Of these 29 lesions, 23 were treated successfully, 5 developed Q wave myocardial infarction and 1 died.
基金Project supported by the National Natural Science Foundation of China (Grant No.60977049)the Chinese Universities Scientific Fund (Grant No.BUPT 2009RC0413)
文摘Generation of single-sideband （SSB） multi-carrier source based on a recirculating frequency shifter （RFS） is anal- ysed theoretically and realized experimentally. The effects of affecting factors originating from the deviation from the right operation bias voltage and unbalanced amplitude, and the phase of the radio frequency （RF） drive signals on the performance of the multi-tone source are discussed in detail. Based on the theoretical analysis, high-quality 50-tone out- put is successfully realized. Experiments under some implementation imperfections are also carried out. The imperfect and low-quality output results are in good agreement with theoretical analysis.
基金Research on Techniques of Predicting the Prospects of Drought and Flood Years inGuangdong – a project of the Science and Technology Plan of Guangdong Province (2005B32601007)Experiments with the Coupling between Typhoons, Waves and Storm Surges and Pre-estimation of Typhoon-inflicted Dagames, a project of the Research Fund for Tropical Oceanic and Meteorological Science
文摘The characteristics of temporal and spatial distribution of tropical cyclone frequencies over the South China Sea areas and its affecting factors in the past 50yrs are analyzed based on typhoon data that provided by CMA and Simple Ocean Data Assimilation （SODA）. The results show that the tropical cyclone frequencies from June to October show concentrated geographic distribution, for they mainIy distribute over the SCS area from 15 - 20°N. The characteristics present significant interdecadal changes. The impact of oceanic factors on the tropical cyclone frequencies in the SCS area is mainly realized by La Nina and La Nifia-like events before 1975 but mainly by E1 Nino and E1 Nifio-like events after 1975.
文摘This paper analyzes the factors that affect Intellectual Property Right(IPR) development by leveraging the way of system engineering.With scale and relationship as the objects of study,this paper explores the relationships among different factors by way of modeling,summarizes the superficial,shallow and deep reasons at different layers that affect enterprise intellectual property rights,and makes clear the correlation among all factors.
文摘Factors affecting equipment maintenance quality usually include personnel,equipment and facilities,raw materials and spare parts, craft, environment and quality management. These six factors affecting maintenance quality are not all the same degree. In order to find out which factor can influence equipment maintenance quality greatly and achieve sophisticated management,characteristic quantities of six factors are presented. A structural equation modeling( SEM) is designed using the six factors as latent variables and their characteristic quantities as the observed variable.According to the basic data obtained from the questionnaire survey,calculate the standardized regression weight by parameter estimation of the SEM. Then the key factors affecting the quality of the equipment maintenance are determined with the help of the standardized regression weight.
文摘Following improvements in evidential thinking,more questions have been raised about the probative values of criminal investigation records;therefore,there is an urgent need to investigate the prominent problems with this system for keeping investigation notes and evidence.The binding 2013 Criminal Procedural Law of the People’s Republic of China lists the victim’s statement,defendant’s confession or defence,inspection,examination,identification,and investigation notes as statutory evidence.Technically,these criminal investigation records are naturally legally admissible as evidenced in criminal justice procedures.However,the Miranda rules of the United States,which guarantee the defendant’s right to silence,have not been established in China's Mainland.Consequently,the objectivity of those kinds of criminal investigation records can be questioned during cross‑examination.Comparative and systematic research methods were used to examine the probative values and their affecting factors in criminal investigation records.The results show that it is not easy to obtain the full probative value of criminal investigation records because it involves analyses of issues such as understanding the notes,procedures,and methods in making the records,as well as the reform of related systems,such as transplanting the Miranda rules to secure the defendant’s right to silence and the presence of counsel.Only in this way can we expect evidence used in criminal investigation records to be used scientifically by ensuring that evidence of criminal acts are kept free from irrational contamination and resolve the existing related problems in judicial practice.
基金Projects BK2007145 supported by the Jiangsu Natural Science Foundation of China NCET-04-0454 by the Program for New Century Excellent Talentsin Universities
文摘In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.
基金supported by the National Natural Science Foundation of China.(NSFC,71373090,‘Study on the gatekeeper policy of CHS’)
文摘The gatekeeper policy has been implemented for approximately ten years on a pilot population in China. It is necessary to assess the satisfaction of patients utilizing community health service（CHS） under the gatekeeper system. Our study showed that the cognition of gatekeeper policy was associated with four dimensions including doctor‐patient relationships, information and support, organization of care, and accessibility（P 〈 0.001）. One or more factors such as gender and self‐perceived health scores also affected their satisfaction. General practitioners must be prepared to focus on these aspects of information and support, organization of care, and accessibility as indicators of potential opportunities for improvement. Additionally, policymakers can improve patients＇ satisfaction with CHS by strengthening their awareness of the gatekeeper policy.
文摘The effects of prestrain and annealing temperature on phase transformation temperatures in Fel4Mn5Si8Cr4Ni shape memory alloy have been studied. The results showed that when the annealing temperature was 673 K, both the At and the Ms temperatures increased appreciably as the prestrain increased, the As temperature increased slightly with increasing prestrain; the resistivity difference at 303 K between the heating and cooling curve also increased with increasing prestrain, which agreed with the recovery strain. The shape memory effect in Fe-Mn-Si-Cr-Ni shape memory alloy is caused by the stress-induced γ→ε martensite transformation and its reverse transformation. When the prestrain was 10%, the Ms temperature decreased remarkably as the annealing temperature increased.
文摘BACKGROUND: Assessing and evaluating mental health status can provide educational planners valuable information to predict the quality of physicians' performance at work. These data can help physicians to practice in the most desired way. The study aimed to evaluate factors affecting psychological morbidity in Iranian emergency medicine practitioners at educational hospitals of Tehran.METHODS: In this cross sectional study 204 participants(emergency medicine residents and specialists) from educational hospitals of Tehran were recruited and their psychological morbidity was assessed by using a 28-question Goldberg General Health Questionnaire(GHQ-28). Somatization, anxiety and sleep disorders, social dysfunction and depression were evaluated among practitioners and compared to demographic and job related variables.RESULTS: Two hundreds and four participants consisting of 146(71.6%) males and 58(28.4%) females were evaluated. Of all participants, 55(27%) were single and 149(73%) were married. Most of our participants(40.2%) were between 30–35 years old. By using GHQ-28, 129(63.2%) were recognized as normal and 75(36.8%) suffered some mental health disorders. There was a signifi cant gender difference between normal practitioners and practitioners with disorder(P=0.02) while marital status had no significant difference(P=0.2). Only 19(9.3%) declared having some major mental health issue in the previous month.CONCLUSION: Females encountered more mental health disorders than male(P=0.02) and the most common disorder observed was somatization(P=0.006).
文摘Coal mining with ploughs is an ideal coal mining technology for thin and thinner coal seams. The existence conditions of coal seams are different for each other, which affects coal mining with ploughs to different degrees, and the application results are also different. The authors analyze the affecting factors by means of mathematical methods. The research is useful to the wide application of ploughs.
