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
Young adults in China are embracing a new way of nightlife-attending night schools for personal growth.“Guess which saves more space?Folding your clothes or hanging them in the closet?”asked Li Jing as she took out ...Young adults in China are embracing a new way of nightlife-attending night schools for personal growth.“Guess which saves more space?Folding your clothes or hanging them in the closet?”asked Li Jing as she took out various hangers.“Actually,as long as you divide your wardrobe into a long clothing zone and a short clothing zone according to your dressing habit,you’ll find that hanging them is much more convenient and space saving,”she said to her evening class of over 20 attentive young people.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
In Beijing opera. and many other traditional operas, the jing roles. or warriors, usually have their faces painted in colorful designs to represent various elements of their character. Each color has its own meaning. ...In Beijing opera. and many other traditional operas, the jing roles. or warriors, usually have their faces painted in colorful designs to represent various elements of their character. Each color has its own meaning. Red stands for loyalty and bravery: black for courage and honesty. and white is the color of deceitfulness.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
21.What we want is to see the child in pursuit of knowledge,and not knowledge in pur suit of the child.22.It is most unwise for people in love to marry.23.Behind every successful man,there is a woman and behind every ...21.What we want is to see the child in pursuit of knowledge,and not knowledge in pur suit of the child.22.It is most unwise for people in love to marry.23.Behind every successful man,there is a woman and behind every unsuccessful there are two.24.There is only one religion,though there are a hundred versions of it.展开更多
AIM: To evaluate the efficacy of the two-surgeon technique with the liver hanging maneuver (LHM) for hepatectomies in pediatric patients with hepatoblastoma. METHODS: Three pediatric patients with hepatoblastoma w...AIM: To evaluate the efficacy of the two-surgeon technique with the liver hanging maneuver (LHM) for hepatectomies in pediatric patients with hepatoblastoma. METHODS: Three pediatric patients with hepatoblastoma were enrolled in this study. Two underwent right hemi-hepatectomies and one underwent a left hemihepatectomy using the two-surgeon technique by means of saline-linked electric cautery (SLC) and the Cavitron Ultrasonic Surgical Aspirator (CUSA; Valleylab, Boulder, CO) and the LHM. RESULTS: The mean operative time during the parenchymal transections was 50 rain and the mean blood loss was 235 g. There was no bile leakage from the cut surface after surgery. No macroscopic or microscopic-positive margins were observed in the hepatic transections. CONCLUSION: The two-surgeon technique using SLC and CUSA with the LHM is applicable to even pediatric patients with hepatoblastoma.展开更多
A preliminary study of the PGA attenuation, hanging wall effect and velocity pulse characteristics from the 2008 Wenchuan earthquake ofMS -8.0 is described in this paper. The study was carried out through analyses in ...A preliminary study of the PGA attenuation, hanging wall effect and velocity pulse characteristics from the 2008 Wenchuan earthquake ofMS -8.0 is described in this paper. The study was carried out through analyses in the time and frequency domains of main earthquake records. In the PGA attenuation study, records from 316 stations less than 1000 km from the surface rupture of the fault were used as a database and attenuation relationships were developed and compared with some existing relationships that are widely used in China's Mainland, Chinese Taiwan and the US. At the same time, records from 28 stations less than 100 km from the fault were used to study the hanging wall effect and velocity pulse characteristics of this earthquake based on the distribution of PGA, PGV, spectral acceleration, and the velocity pulse peak, and the results are compared with the 1999 Chi-Chi earthquake. In addition, the large PGAs of the UD components observed in this event are also discussed in this paper. From the results of the preliminary study, some conclusions are developed and suggestions for further research are proposed.展开更多
In re-entry, the drilling riser hanging to the holding vessel takes on a free hanging state, waiting to be moved from the initial random position to the wellhead. For the re-entry, dynamics calculation is often done t...In re-entry, the drilling riser hanging to the holding vessel takes on a free hanging state, waiting to be moved from the initial random position to the wellhead. For the re-entry, dynamics calculation is often done to predict the riser motion or evaluate the structural safety. A dynamics calculation method based on Flexible Segment Model (FSM) is proposed for free hanging marine risers. In FSM, a riser is discretized into a series of flexible segments. For each flexible segment, its deflection feature and external forces are analyzed independently. For the whole riser, the nonlinear governing equations are listed according to the moment equilibrium at nodes. For the solution of the nonlinear equations, a linearization iteration scheme is provided in the paper. Owing to its flexibility, each segment can match a long part of the riser body, which enables that good results can be obtained even with a small number of segments. Moreover, the linearization iteration scheme can avoid widely used Newton-Rapson iteration scheme in which the calculation stability is influenced by the initial points. The FSM-based dynamics calculation is timesaving and stable, so suitable for the shape prediction or real-time control of free hanging marine risers.展开更多
AIM: To review 11 patients with parasitic cysts of the liver, who were treated by hepatic Iobectomy using the liver hanging maneuver (LHM).METHODS: Between January 2003 and June 2006, we retrospectively analyzed p...AIM: To review 11 patients with parasitic cysts of the liver, who were treated by hepatic Iobectomy using the liver hanging maneuver (LHM).METHODS: Between January 2003 and June 2006, we retrospectively analyzed patients who underwent surgical treatment due to parasitic cysts of the liver, at the Ege University School of Medicine, Department of General Surgery. Of these, the patients who underwent hepatic lobectomy using the LHM were reviewed and evaluated for surgical treatment outcome.RESULTS: Over a three-year period, there were 102 patients who underwent surgical treatment for parasitic cysts of the liver. Of these, 11 (10%) patients with parasitic cysts of the liver underwent hepatic Iobectomy using the LHM. Presenting symptoms were abdominal pain, dyspepsia, and cholangitis. Cyst locations were as follows: right lobe filled with cyst, 7 (63%); segmental location, 2 (18%); and multiple locations, 2 patients (18%). All patients underwent hepatic Iobectomy with an anterior approach using the LHM. The intraoperative blood transfusion requirement was one unit for 3 patients and two units for one patient. Postoperative complications included pulmonary atelectasy (2, 18%) and pleural effusion (2, 18%). No significant morbidity or mortality was observed.CONCLUSION: We concluded that hepatic Iobectomy using the LHM should be considered, not only for hepatic tumors or donor hepatectomy, but also to treat parasitic cysts of the liver.展开更多
Hanging roofs or high hang-ups.a common problem in sublevel caving mining,usually result in a large ore loss and undermine mining safety.This paper analyzed the formation of a hanging roof and showed that increased co...Hanging roofs or high hang-ups.a common problem in sublevel caving mining,usually result in a large ore loss and undermine mining safety.This paper analyzed the formation of a hanging roof and showed that increased confining pressure and reduced free surface were its main characteristics.In order to break down a hanging roof,a new method based on shock wave collision and stress superposition was developed.In this method,two blastholes containing multi-primer at different positions are simultaneously initiated at first.By doing this,a new free surface and a swell room can be created.After these holes are fired,a long delay time is given to the next blasthole so that the fragments from the first twohole blasting have enough time to fall down.This new method was applied to three hanging roofs in one production area,and all of them were successfully broken down.Field inspection indicated that almost no damage was caused in the nearby drifts/tunnels due to the new method.In addition,the far field vibrations were found to be smaller than the maximum vibrations induced by some other blasts.展开更多
BACKGROUND: Pancreatic adenocarcinoma remains the fourth leading cause of cancer-related death and is one of the most aggressive human tumors. At present, surgical resection is the only potentially curative treatment....BACKGROUND: Pancreatic adenocarcinoma remains the fourth leading cause of cancer-related death and is one of the most aggressive human tumors. At present, surgical resection is the only potentially curative treatment. Early neck division is inadequate when invasion of the superior mesenteric artery (SMA) is suspected or in cases of replaced or accessory right hepatic artery. Malignant periampullary tumors often invade retroperitoneal peripancreatic tissues and a positive resection margin is associated with a poor long-term survival. DATA SOURCES: English-language medical databases, PubMed, ELSEVIER and SPRINGERLINK, were searched for articles on 'posterior approach pancreaticoduodenectomy', 'superior mesenteric artery first approach', 'retroperitoneal tissue', 'hanging maneuver', and related topics. RESULTS: The modification allowed the surgeon to early identify the nonresectability of a replaced right hepatic artery if present, enabling complete dissection of the right side of the SMA and portal vein as well as complete excision of the retroportal pancreatic lamina. CONCLUSION: Pancreaticoduodenectomy with early retropancreatic dissection is a useful and safe technical variant, which is indicated for the improvement of the safety and curative effect of the procedure. (Hepatobiliary Pancreat Dis Int 2010; 9: 579-583)展开更多
BACKGROUND Hanging is one of the most commonly used methods for suicide in both sexes worldwide.In a number of countries,hanging mortality has increased over the last decades.Nevertheless,there is a scarcity of studie...BACKGROUND Hanging is one of the most commonly used methods for suicide in both sexes worldwide.In a number of countries,hanging mortality has increased over the last decades.Nevertheless,there is a scarcity of studies that have explored the patterns and trends for mortality of suicide by hanging on global,regional and national levels,as most evaluations are limited to certain populations.AIM To assess the trends of suicide mortality by hanging,strangulation,and suffocation in Serbia,from 1991 to 2020.METHODS This nationwide study,with epidemiological descriptive study design,was carried out based on official data.The age-standardized rates(ASRs,expressed per 100000 persons)were calculated by direct standardization,using the World Standard Population.Mortality trends from suicide by hanging were assessed using the joinpoint regression analysis:The average annual percent change(AAPC)with the corresponding 95%confidence interval(95%CI)was calculated.Age-period-cohort analysis was performed to address the possible underlying reasons for the observed suicide trends.RESULTS Over the 30-year period studied,there were 24340 deaths by hanging(17750 males and 6590 females)in Serbia.In 2020,the ASR of deaths by hanging was 4.5 per 100000 persons in both sexes together(7.6 in males vs 1.7 in females).The trends of suicide mortality by hanging decreased significantly between 1991 and 2020 in both males(AAPC=-1.7%per year;95%CI:-2.0 to-1.4)and females(AAPC=-3.5%per year;95%CI:-3.9 to-3.1).Mortality rates of suicide by hanging had a continuously decreasing tendency in both sexes together in all age groups:The only exception was among males in 40-49 age group,with an increasing trend of suicide by hanging from 1991 to 2011(by+0.3%per year).CONCLUSION The trends in suicide mortality by hanging have been decreasing in Serbia in the last three decades in both sexes,but this was more pronounced in women than in men.Despite the decreasing trends observed in mortality of suicide by hanging,further research is needed for better clarification of trends and help in suicide prevention in the future.展开更多
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.
文摘Young adults in China are embracing a new way of nightlife-attending night schools for personal growth.“Guess which saves more space?Folding your clothes or hanging them in the closet?”asked Li Jing as she took out various hangers.“Actually,as long as you divide your wardrobe into a long clothing zone and a short clothing zone according to your dressing habit,you’ll find that hanging them is much more convenient and space saving,”she said to her evening class of over 20 attentive young people.
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.
文摘In Beijing opera. and many other traditional operas, the jing roles. or warriors, usually have their faces painted in colorful designs to represent various elements of their character. Each color has its own meaning. Red stands for loyalty and bravery: black for courage and honesty. and white is the color of deceitfulness.
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.
文摘21.What we want is to see the child in pursuit of knowledge,and not knowledge in pur suit of the child.22.It is most unwise for people in love to marry.23.Behind every successful man,there is a woman and behind every unsuccessful there are two.24.There is only one religion,though there are a hundred versions of it.
文摘AIM: To evaluate the efficacy of the two-surgeon technique with the liver hanging maneuver (LHM) for hepatectomies in pediatric patients with hepatoblastoma. METHODS: Three pediatric patients with hepatoblastoma were enrolled in this study. Two underwent right hemi-hepatectomies and one underwent a left hemihepatectomy using the two-surgeon technique by means of saline-linked electric cautery (SLC) and the Cavitron Ultrasonic Surgical Aspirator (CUSA; Valleylab, Boulder, CO) and the LHM. RESULTS: The mean operative time during the parenchymal transections was 50 rain and the mean blood loss was 235 g. There was no bile leakage from the cut surface after surgery. No macroscopic or microscopic-positive margins were observed in the hepatic transections. CONCLUSION: The two-surgeon technique using SLC and CUSA with the LHM is applicable to even pediatric patients with hepatoblastoma.
基金National Natural Science Foundation of China Under Grant No. 90715038 National Basic Research Program of China Under Grant No. 2007CB71420)the Basic Science & Research Foundation of Institute of Engineering Mechanics, CEA Under Grant No. 2006A02
文摘A preliminary study of the PGA attenuation, hanging wall effect and velocity pulse characteristics from the 2008 Wenchuan earthquake ofMS -8.0 is described in this paper. The study was carried out through analyses in the time and frequency domains of main earthquake records. In the PGA attenuation study, records from 316 stations less than 1000 km from the surface rupture of the fault were used as a database and attenuation relationships were developed and compared with some existing relationships that are widely used in China's Mainland, Chinese Taiwan and the US. At the same time, records from 28 stations less than 100 km from the fault were used to study the hanging wall effect and velocity pulse characteristics of this earthquake based on the distribution of PGA, PGV, spectral acceleration, and the velocity pulse peak, and the results are compared with the 1999 Chi-Chi earthquake. In addition, the large PGAs of the UD components observed in this event are also discussed in this paper. From the results of the preliminary study, some conclusions are developed and suggestions for further research are proposed.
基金supported by the National Natural Science Foundation of China (Grant No. 51009092)the Doctoral Foundation of Education Ministry of China (Grant No. 20090073120013)the Scientific Research Foundation of State Education Ministry for the Returned Overseas Chinese Scholars
文摘In re-entry, the drilling riser hanging to the holding vessel takes on a free hanging state, waiting to be moved from the initial random position to the wellhead. For the re-entry, dynamics calculation is often done to predict the riser motion or evaluate the structural safety. A dynamics calculation method based on Flexible Segment Model (FSM) is proposed for free hanging marine risers. In FSM, a riser is discretized into a series of flexible segments. For each flexible segment, its deflection feature and external forces are analyzed independently. For the whole riser, the nonlinear governing equations are listed according to the moment equilibrium at nodes. For the solution of the nonlinear equations, a linearization iteration scheme is provided in the paper. Owing to its flexibility, each segment can match a long part of the riser body, which enables that good results can be obtained even with a small number of segments. Moreover, the linearization iteration scheme can avoid widely used Newton-Rapson iteration scheme in which the calculation stability is influenced by the initial points. The FSM-based dynamics calculation is timesaving and stable, so suitable for the shape prediction or real-time control of free hanging marine risers.
文摘AIM: To review 11 patients with parasitic cysts of the liver, who were treated by hepatic Iobectomy using the liver hanging maneuver (LHM).METHODS: Between January 2003 and June 2006, we retrospectively analyzed patients who underwent surgical treatment due to parasitic cysts of the liver, at the Ege University School of Medicine, Department of General Surgery. Of these, the patients who underwent hepatic lobectomy using the LHM were reviewed and evaluated for surgical treatment outcome.RESULTS: Over a three-year period, there were 102 patients who underwent surgical treatment for parasitic cysts of the liver. Of these, 11 (10%) patients with parasitic cysts of the liver underwent hepatic Iobectomy using the LHM. Presenting symptoms were abdominal pain, dyspepsia, and cholangitis. Cyst locations were as follows: right lobe filled with cyst, 7 (63%); segmental location, 2 (18%); and multiple locations, 2 patients (18%). All patients underwent hepatic Iobectomy with an anterior approach using the LHM. The intraoperative blood transfusion requirement was one unit for 3 patients and two units for one patient. Postoperative complications included pulmonary atelectasy (2, 18%) and pleural effusion (2, 18%). No significant morbidity or mortality was observed.CONCLUSION: We concluded that hepatic Iobectomy using the LHM should be considered, not only for hepatic tumors or donor hepatectomy, but also to treat parasitic cysts of the liver.
文摘Hanging roofs or high hang-ups.a common problem in sublevel caving mining,usually result in a large ore loss and undermine mining safety.This paper analyzed the formation of a hanging roof and showed that increased confining pressure and reduced free surface were its main characteristics.In order to break down a hanging roof,a new method based on shock wave collision and stress superposition was developed.In this method,two blastholes containing multi-primer at different positions are simultaneously initiated at first.By doing this,a new free surface and a swell room can be created.After these holes are fired,a long delay time is given to the next blasthole so that the fragments from the first twohole blasting have enough time to fall down.This new method was applied to three hanging roofs in one production area,and all of them were successfully broken down.Field inspection indicated that almost no damage was caused in the nearby drifts/tunnels due to the new method.In addition,the far field vibrations were found to be smaller than the maximum vibrations induced by some other blasts.
文摘BACKGROUND: Pancreatic adenocarcinoma remains the fourth leading cause of cancer-related death and is one of the most aggressive human tumors. At present, surgical resection is the only potentially curative treatment. Early neck division is inadequate when invasion of the superior mesenteric artery (SMA) is suspected or in cases of replaced or accessory right hepatic artery. Malignant periampullary tumors often invade retroperitoneal peripancreatic tissues and a positive resection margin is associated with a poor long-term survival. DATA SOURCES: English-language medical databases, PubMed, ELSEVIER and SPRINGERLINK, were searched for articles on 'posterior approach pancreaticoduodenectomy', 'superior mesenteric artery first approach', 'retroperitoneal tissue', 'hanging maneuver', and related topics. RESULTS: The modification allowed the surgeon to early identify the nonresectability of a replaced right hepatic artery if present, enabling complete dissection of the right side of the SMA and portal vein as well as complete excision of the retroportal pancreatic lamina. CONCLUSION: Pancreaticoduodenectomy with early retropancreatic dissection is a useful and safe technical variant, which is indicated for the improvement of the safety and curative effect of the procedure. (Hepatobiliary Pancreat Dis Int 2010; 9: 579-583)
基金Supported by Ministry of Education,Science and Technological Development,Republic of Serbia, 2011–2020, No. 175042
文摘BACKGROUND Hanging is one of the most commonly used methods for suicide in both sexes worldwide.In a number of countries,hanging mortality has increased over the last decades.Nevertheless,there is a scarcity of studies that have explored the patterns and trends for mortality of suicide by hanging on global,regional and national levels,as most evaluations are limited to certain populations.AIM To assess the trends of suicide mortality by hanging,strangulation,and suffocation in Serbia,from 1991 to 2020.METHODS This nationwide study,with epidemiological descriptive study design,was carried out based on official data.The age-standardized rates(ASRs,expressed per 100000 persons)were calculated by direct standardization,using the World Standard Population.Mortality trends from suicide by hanging were assessed using the joinpoint regression analysis:The average annual percent change(AAPC)with the corresponding 95%confidence interval(95%CI)was calculated.Age-period-cohort analysis was performed to address the possible underlying reasons for the observed suicide trends.RESULTS Over the 30-year period studied,there were 24340 deaths by hanging(17750 males and 6590 females)in Serbia.In 2020,the ASR of deaths by hanging was 4.5 per 100000 persons in both sexes together(7.6 in males vs 1.7 in females).The trends of suicide mortality by hanging decreased significantly between 1991 and 2020 in both males(AAPC=-1.7%per year;95%CI:-2.0 to-1.4)and females(AAPC=-3.5%per year;95%CI:-3.9 to-3.1).Mortality rates of suicide by hanging had a continuously decreasing tendency in both sexes together in all age groups:The only exception was among males in 40-49 age group,with an increasing trend of suicide by hanging from 1991 to 2011(by+0.3%per year).CONCLUSION The trends in suicide mortality by hanging have been decreasing in Serbia in the last three decades in both sexes,but this was more pronounced in women than in men.Despite the decreasing trends observed in mortality of suicide by hanging,further research is needed for better clarification of trends and help in suicide prevention in the future.