Objective: Conservative restoration principles that accurately reduce plaque accumulation are the goals of restorative dentistry. Correct and perfect restoration has an important effect on health of periodontious tiss...Objective: Conservative restoration principles that accurately reduce plaque accumulation are the goals of restorative dentistry. Correct and perfect restoration has an important effect on health of periodontious tissues. This study was done to compare the methods of oral hygiene, over hanged removal and restoration changing on periodontal health and alveolar bone height of restored mandible molars with proximal over hanged amalgam. Materials and Methods: All patients with over hanged amalgam restoration were randomly divided into three groups. In order to survey the effect of over hanged removal on gingival and bleeding indices and alveolar bone height adjacent to mandible molar teeth, these indices were determined according to recurrent radio-graphical early signs of alveolar bone loss during three months. Sixty patients, 20 in each group, were studied. In the group I, overhang was removed with ultrasonic scale or bur and oral hygiene methods as usual were continued. In the group II, over-hang was left, but plaque controls as the prophylaxis and flossing were done. In the group III, restoration was changed and oral hygiene was done as usual. Plaque index and bleeding index were measured at the beginning of study and three months later. Findings: Statistical analysis of studied indices at the beginning and three months after treatment using paired test has shown significant differences in gingival inflammation, in all groups. Statistical analysis of indices using Tukey HSD test has also shown significant differences in decreasing gingival inflammation measure when the over hanged restoration was removed. While there is no difference between the other two groups. Conclusion: The results showed that plaque control causes subsidence of gingival inflammation and increasing of alveolar bone support, and it is more effective when the over hanged restoration is changed.展开更多
Dominated by an arid and semiarid continental climate,the Beijing-Tianjin Sandstorm Source Region(BTSSR)is a typical ecologically fragile region with frequently occurring droughts.To provide information for regional v...Dominated by an arid and semiarid continental climate,the Beijing-Tianjin Sandstorm Source Region(BTSSR)is a typical ecologically fragile region with frequently occurring droughts.To provide information for regional vegetation protection and drought prevention,we assessed the relations between vegetation cover change(measured by the Normalized Difference Vegetation Index,NDVI)and the Standardized Precipitation Evapotranspiration Index(SPEI)at different time-scales,in different growth stages,in different subregions and for different vegetation types based on the Pearson's correlation coefficient in the BTSSR from 2000 to 2017.Results showed that 88.19%of the vegetated areas experienced increased NDVI in the growing season;48.3%of the vegetated areas experi-enced significantly increased NDVI(P<0.05)and were mainly in the south of the BTSSR.During the growing season,a wetter climate contributed to the increased vegetation cover from 2000 to 2017,and NDVI anomalies were closely related to SPEI.The maximum correlation coefficient in the growing season(Rmax)was significantly positive(P<0.05)in 97.84%of the total vegetated areas.In the vegetated areas with significantly positive Rmax,pixels with short time-scales(1-3 mon)accounted for the largest proportion(33.9%).The sensitivity of vegetation to the impact of drought rose first and then decreased in the growing season,with a peak in July.Compared with two subregions in the south,subregions in the north of the BTSSR were more sensitive to the impacts of drought variations,especially in the Xilingol Plateau and Wuzhumuqin Basin.All four major vegetation types were sensitive to the effects of drought variations,especially grasslands.The time-scales of the most impacting droughts varied with growth stages,regions,and vegetation types.These results can help us understand the relations between vegetation and droughts,which are important for ecological restoration and drought prevention.展开更多
The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the e...The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.展开更多
Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admit...Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admitted to our hospital from October 2021 to March 2022 and met the inclusion criteria were randomly divided into two groups of 30 cases each;the treatment group was treated with anal adenectomy and virtual hanging wire surgery,and the control group was treated with anal fistula resection.The clinical efficacy after treatment was compared.Results:The total effective rate of both groups was 96.67%and the difference between the two groups was not statistically significant(P>0.05).The postoperative pain score of the treatment group was lower than that of the control group(P<0.05).The length of hospitalization and healing time of the treatment group was lower than that of the control group(P<0.05).The anal function of the patients in both groups was normal,and there was no adverse reaction.Conclusion:Anal gland excision and virtual hanging surgery for the treatment of low anal fistula in infants and children have the advantages of mild pain,reduced length of hospitalization,short healing time,and better patient experience as compared to anal fistula excision.展开更多
Artificial nest boxes are placed to attract birds to nest and breed in a specific location,and they are widely used in avian ecology research and in the attraction of insectivorous birds.There is evidence that artific...Artificial nest boxes are placed to attract birds to nest and breed in a specific location,and they are widely used in avian ecology research and in the attraction of insectivorous birds.There is evidence that artificial nest boxes can adversely affect breeding fitness but no great focus has been placed on this issue by researchers.Therefore,we retrieved 321 research papers regarding artificial nest boxes published from 2003 to 2022 and used the'Biblioshiny'program to extract and integrate keywords;we then summarized the adverse effects of artificial nest boxes on avian breeding success.The studies highlighted many drawbacks and misuses in the designing and placement of nest boxes;furthermore,bird attraction was decreased by their inappropriate selection,thus reducing breeding success.Regarding nest box production,there were shortcomings in the construction material,color,smell,and structural design of the boxes used.Nest boxes were also placed at inappropriate densities,locations,orientations,heights,and managed incorrectly.Finally,we propose suggestions for more efficient and safer artificial nest boxes for future use in avian ecology research and bird conservation.展开更多
This paper addresses the change of the river-lake relationship in the Huai River and its causes due to environmental change and human activities. A preliminary analysis is made from three aspects: (1) the natural geog...This paper addresses the change of the river-lake relationship in the Huai River and its causes due to environmental change and human activities. A preliminary analysis is made from three aspects: (1) the natural geographical change particularly captured by the Yellow River, (2) water conservancy project construction, and (3) socioeconomic development in the Huai River Basin. Key problems of changes in this river-lake relationship and the Huai River flood control are tackled, involving flood control and disaster alleviation ability of the Basin, engineering and non-engineering measurements applied to flood control and disaster mitigation, and water governance for adaptive management. Research shows that the Huai River is a rather complex one due to its complex geography with a hybrid wet and dry climate zoon, and higher population density. With the alternation of the river-lake relationship and socioeconomic development in the region, new problems keep arising, imposing new requirements on its sustainable water management. Thus, understanding the Huai River is a long and gradually improving process. Its future planning should keep absorbing new achievements of science and technology development, employing new technologies and methods, and gradually deepening our understanding of its fundamental principles. Water governance and adaptive water management will be new challenges and opportunities for the Basin in its river system change and flood control.展开更多
Two friends were eating at a small inn.On the table there wasa cup of hot mustard(芥茉).One of them thought it was sweetand took a spoonful of it into his mouth.Tears ran down hischeeks.Nevertheless,wishing to have hi...Two friends were eating at a small inn.On the table there wasa cup of hot mustard(芥茉).One of them thought it was sweetand took a spoonful of it into his mouth.Tears ran down hischeeks.Nevertheless,wishing to have his friend caught in the sametrap,he said nothing.The other man,seeing that his friend wascrying,asked,“What for,my dear friend?”展开更多
学习英语的关键是掌握好动词,要掌握好动词,必须区分容易混淆的动词。现请用下列动词的适当形式填空。1.lay/lie/lie 1)She__down and fell asleep. 2)Obviously he was__. 3)She__her baby gently down on the bed.2.hanged/hung 1)It ...学习英语的关键是掌握好动词,要掌握好动词,必须区分容易混淆的动词。现请用下列动词的适当形式填空。1.lay/lie/lie 1)She__down and fell asleep. 2)Obviously he was__. 3)She__her baby gently down on the bed.2.hanged/hung 1)It is said that the spy is to be__tomorrow. 2)A light__above the table.展开更多
文摘Objective: Conservative restoration principles that accurately reduce plaque accumulation are the goals of restorative dentistry. Correct and perfect restoration has an important effect on health of periodontious tissues. This study was done to compare the methods of oral hygiene, over hanged removal and restoration changing on periodontal health and alveolar bone height of restored mandible molars with proximal over hanged amalgam. Materials and Methods: All patients with over hanged amalgam restoration were randomly divided into three groups. In order to survey the effect of over hanged removal on gingival and bleeding indices and alveolar bone height adjacent to mandible molar teeth, these indices were determined according to recurrent radio-graphical early signs of alveolar bone loss during three months. Sixty patients, 20 in each group, were studied. In the group I, overhang was removed with ultrasonic scale or bur and oral hygiene methods as usual were continued. In the group II, over-hang was left, but plaque controls as the prophylaxis and flossing were done. In the group III, restoration was changed and oral hygiene was done as usual. Plaque index and bleeding index were measured at the beginning of study and three months later. Findings: Statistical analysis of studied indices at the beginning and three months after treatment using paired test has shown significant differences in gingival inflammation, in all groups. Statistical analysis of indices using Tukey HSD test has also shown significant differences in decreasing gingival inflammation measure when the over hanged restoration was removed. While there is no difference between the other two groups. Conclusion: The results showed that plaque control causes subsidence of gingival inflammation and increasing of alveolar bone support, and it is more effective when the over hanged restoration is changed.
基金Under the auspices of National Natural Science Foundation of China(No.41807177,41701017)the Pioneer‘Hundred Talents Program’of Chinese Academy of Sciences。
文摘Dominated by an arid and semiarid continental climate,the Beijing-Tianjin Sandstorm Source Region(BTSSR)is a typical ecologically fragile region with frequently occurring droughts.To provide information for regional vegetation protection and drought prevention,we assessed the relations between vegetation cover change(measured by the Normalized Difference Vegetation Index,NDVI)and the Standardized Precipitation Evapotranspiration Index(SPEI)at different time-scales,in different growth stages,in different subregions and for different vegetation types based on the Pearson's correlation coefficient in the BTSSR from 2000 to 2017.Results showed that 88.19%of the vegetated areas experienced increased NDVI in the growing season;48.3%of the vegetated areas experi-enced significantly increased NDVI(P<0.05)and were mainly in the south of the BTSSR.During the growing season,a wetter climate contributed to the increased vegetation cover from 2000 to 2017,and NDVI anomalies were closely related to SPEI.The maximum correlation coefficient in the growing season(Rmax)was significantly positive(P<0.05)in 97.84%of the total vegetated areas.In the vegetated areas with significantly positive Rmax,pixels with short time-scales(1-3 mon)accounted for the largest proportion(33.9%).The sensitivity of vegetation to the impact of drought rose first and then decreased in the growing season,with a peak in July.Compared with two subregions in the south,subregions in the north of the BTSSR were more sensitive to the impacts of drought variations,especially in the Xilingol Plateau and Wuzhumuqin Basin.All four major vegetation types were sensitive to the effects of drought variations,especially grasslands.The time-scales of the most impacting droughts varied with growth stages,regions,and vegetation types.These results can help us understand the relations between vegetation and droughts,which are important for ecological restoration and drought prevention.
基金the scientific research foundation of Zhejiang Provincial Natural Science Foundation of China (LTGG24E090002)Zhejiang University of Water Resources and Electric Power (xky2022013)+1 种基金Major Science and Technology Plan Project of Zhejiang Provincial Department of Water Resources (RA1904)the water conservancy management department, Zhejiang Design Institute of Water Conservancy and Hydro Electric Power Co., Ltd. and the construction company for their support。
文摘The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.
基金Xi’an Municipal Bureau of Science and Technology,No.21YXYJ0060。
文摘Objective:To compare the efficacy of anal adenectomy with virtual hanging wire and anal fistulotomy in the treatment of low anal fistula in infants and children.Methods:60 children with low anal fistula who were admitted to our hospital from October 2021 to March 2022 and met the inclusion criteria were randomly divided into two groups of 30 cases each;the treatment group was treated with anal adenectomy and virtual hanging wire surgery,and the control group was treated with anal fistula resection.The clinical efficacy after treatment was compared.Results:The total effective rate of both groups was 96.67%and the difference between the two groups was not statistically significant(P>0.05).The postoperative pain score of the treatment group was lower than that of the control group(P<0.05).The length of hospitalization and healing time of the treatment group was lower than that of the control group(P<0.05).The anal function of the patients in both groups was normal,and there was no adverse reaction.Conclusion:Anal gland excision and virtual hanging surgery for the treatment of low anal fistula in infants and children have the advantages of mild pain,reduced length of hospitalization,short healing time,and better patient experience as compared to anal fistula excision.
基金supported by the National Natural Science Foundation of China(Grant No.32170485,31501867)the Fundamental Research Funds for the Central Universities(Grant No.2572022BE02)。
文摘Artificial nest boxes are placed to attract birds to nest and breed in a specific location,and they are widely used in avian ecology research and in the attraction of insectivorous birds.There is evidence that artificial nest boxes can adversely affect breeding fitness but no great focus has been placed on this issue by researchers.Therefore,we retrieved 321 research papers regarding artificial nest boxes published from 2003 to 2022 and used the'Biblioshiny'program to extract and integrate keywords;we then summarized the adverse effects of artificial nest boxes on avian breeding success.The studies highlighted many drawbacks and misuses in the designing and placement of nest boxes;furthermore,bird attraction was decreased by their inappropriate selection,thus reducing breeding success.Regarding nest box production,there were shortcomings in the construction material,color,smell,and structural design of the boxes used.Nest boxes were also placed at inappropriate densities,locations,orientations,heights,and managed incorrectly.Finally,we propose suggestions for more efficient and safer artificial nest boxes for future use in avian ecology research and bird conservation.
基金The National Basic Research Program of China (2010CB428406)the National Natural Science Foundation of China (No. 41071025/40730632) & National Key Water Project (No.2009ZX07210-006)
文摘This paper addresses the change of the river-lake relationship in the Huai River and its causes due to environmental change and human activities. A preliminary analysis is made from three aspects: (1) the natural geographical change particularly captured by the Yellow River, (2) water conservancy project construction, and (3) socioeconomic development in the Huai River Basin. Key problems of changes in this river-lake relationship and the Huai River flood control are tackled, involving flood control and disaster alleviation ability of the Basin, engineering and non-engineering measurements applied to flood control and disaster mitigation, and water governance for adaptive management. Research shows that the Huai River is a rather complex one due to its complex geography with a hybrid wet and dry climate zoon, and higher population density. With the alternation of the river-lake relationship and socioeconomic development in the region, new problems keep arising, imposing new requirements on its sustainable water management. Thus, understanding the Huai River is a long and gradually improving process. Its future planning should keep absorbing new achievements of science and technology development, employing new technologies and methods, and gradually deepening our understanding of its fundamental principles. Water governance and adaptive water management will be new challenges and opportunities for the Basin in its river system change and flood control.
文摘Two friends were eating at a small inn.On the table there wasa cup of hot mustard(芥茉).One of them thought it was sweetand took a spoonful of it into his mouth.Tears ran down hischeeks.Nevertheless,wishing to have his friend caught in the sametrap,he said nothing.The other man,seeing that his friend wascrying,asked,“What for,my dear friend?”
文摘学习英语的关键是掌握好动词,要掌握好动词,必须区分容易混淆的动词。现请用下列动词的适当形式填空。1.lay/lie/lie 1)She__down and fell asleep. 2)Obviously he was__. 3)She__her baby gently down on the bed.2.hanged/hung 1)It is said that the spy is to be__tomorrow. 2)A light__above the table.