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Comprehensive analysis of glacier recession(2000-2020)in the Nun-Kun Group of Glaciers,Northwestern Himalaya
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作者 Shakil Ahmad ROMSHOO Ummer AMEEN +1 位作者 Mustafa Hameed BHAT Tariq ABDULLAH 《Journal of Mountain Science》 SCIE CSCD 2024年第3期768-785,共18页
Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In t... Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In this study,changes of 48 glaciers situated around the twin peaks of the Nun and Kun mountains in the northwestern Himalaya,hereafter referred to as Nun-Kun Group of Glaciers(NKGG),were investigated using Landsat satellite data during 2000-2020.Changes in glacier area,snout position,Equilibrium Line Altitude(ELA),surface thickness and glacier velocity were assessed using remote sensing data supplemented by field observations.The study revealed that the NKGG glaciers have experienced a recession of 4.5%±3.4%and their snouts have retreated at the rate of 6.4±1.6 m·a^(-1).Additionally,there was a 41%increase observed in the debris cover area during the observation period.Using the geodetic approach,an average glacier elevation change of-1.4±0.4 m·a^(-1)was observed between 2000 and 2012.The observed mass loss of the NKGG has resulted in the deceleration of glacier velocity from 27.0±3.7 m·a^(-1)in 2000 to 21.2±2.2 m·a^(-1)in 2020.The ELA has shifted upwards by 83.0±22 m during the period.Glacier morphological and topographic factors showed a strong influence on glacier recession.Furthermore,a higher recession of 12.9%±3.2%was observed in small glaciers,compared to 2.7%±3.1%in larger glaciers.The debris-covered glaciers showed lower shrinkage(2.8%±1.1%)compared to the clean glaciers(9.3%±5%).The glacier depletion recorded in the NKGG during the last two decades,if continued,would severely diminish glacial volume and capacity to store water,thus jeopardizing the sustainability of water resources in the basin. 展开更多
关键词 Nun-Kun range Glacier recession Glacier snout Remote Sensing HIMALAYA Glacier velocity
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The impact of earlier flood recession on metacommunity diversity of wintering waterbirds at shallow lakes in the middle and lower Yangtze River floodplain 被引量:1
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作者 Zhenhua Wei Lizhi Zhou 《Avian Research》 SCIE CSCD 2023年第2期223-230,共8页
The hydrological regime in wetlands plays an important role in the process of wintering waterbird metacommunity assemblage.However,increasing frequency of extreme climate and the intensification of human activities,su... The hydrological regime in wetlands plays an important role in the process of wintering waterbird metacommunity assemblage.However,increasing frequency of extreme climate and the intensification of human activities,such as the construction of sluices and dams,have resulted in frequently abnormal hydrological regime in the middle and lower Yangtze River floodplain.In recent years,earlier flood recession has become one of the main hydrological problems faced in the shallow lakes,having a great impact on wetland biodiversity.It is necessary to understand the impact of earlier flood recession on waterbirds,an indicator of wetland biodiversity,and the metacommunity concept is helpful to elucidate the underlying mechanism involved in the processes of assemblage by waterbird communities.In this study,we surveyed the wintering waterbirds at three sub-lakes of Caizi Lakes during 2019-2020 and 2020-2021 and compared the richness,abundance,alpha and beta diversity of waterbirds in and among local metacommunities under earlier flood recession and normal hydrological regime.The results showed that the earlier flood recession reduced the species richness in the early stage and abundance in the late stage,it also reduced the Shannon-Wiener index in the early stage and increased the dissimilarity between and within waterbird metacommunities in the late stage.The partition of beta diversity showed that the turnover component played a major role in the process of waterbird metacommunity assemblage.It was found that the earlier flood recession reduced the richness,abundance in different stages of flood recession,which also increased the turnover of waterbirds.Metacommunities with high habitat heterogeneity had better resistance to abnormal hydrological regime,which resulted in high dissimilarity between and within metacommunities.The results of this study provide important information for waterbird conservation and water level management at shallow lakes in the middle and lower Yangtze River floodplain. 展开更多
关键词 Beta diversity Flood recession Hydrological regime METACOMMUNITY Shallow lake WATERBIRDS
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Comparison of conventional and Hang-back methods of inferior oblique recession in V-pattern strabismus with inferior oblique overaction 被引量:1
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作者 Kamlesh AnAND Ankita Bharadwaj +5 位作者 Shweta Dhiman Yashpal Goel Anju Rastogi Richa Agarwal Manisha Misthra Prateek Kumar 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第6期985-990,共6页
AIM:To compare outcomes of conventional and Hangback methods of inferior oblique(IO)recession in V-pattern strabismus with inferior oblique overaction(IOOA).METHODS:Comparative randomized study was conducted consistin... AIM:To compare outcomes of conventional and Hangback methods of inferior oblique(IO)recession in V-pattern strabismus with inferior oblique overaction(IOOA).METHODS:Comparative randomized study was conducted consisting of 50 patients,age 6 to 35 y having V-pattern strabismus[>15 prism diopter(PD)]with IOOA.They were divided equally in two groups and underwent IO recession,group A by conventional method and group B by Hang-back method.Parameters evaluated were reduction in V-pattern and IOOA,shift in torsion,improvement in binocular status.Success was a residual V-pattern of less than 10 PD at 1 y of follow up.RESULTS:The mean V-pattern preoperatively and postoperatively at 1 y was 24±5.4 PD and 4.2±3.51 PD in group A and 23.44±6.44 PD and 5.76±3.8 PD in group B respectively.The mean reduction in V-pattern was 20±6.78 PD in group A and 18.2±5.48 PD in group B.The mean correction of IOOA was 18.48±3.13 PD in group A and 16±2.93 PD in group B.Mean shift in extorsion was 3.08±1.8 degree in group A and 3.72±2.14 degree in group B.CONCLUSION:Both the procedures achieve a significant and comparable reduction in V-pattern and IOOA.Hang-back recession being a landmark free surgery eliminates the need for intrascleral suturing thereby reducing the risk of scleral perforation with possible postoperative adjustment of muscle.It may be considered as a good alternative for IO recession in patients of V-pattern strabismus with mild to moderate amount of IOOA. 展开更多
关键词 V-pattern inferior oblique overaction Hang-back recession conventional recession
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Comment on “Anterior lamellar recession for management of upper eyelid cicatricial entropion and associated eyelid abnormalities” 被引量:4
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作者 Naser Owji 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第6期1075-1076,共2页
Dear Editor,I read with great interest the article by Gawdat et al^([1]).The authors evaluated the functional and aesthetic outcomes of upper eyelid cicatricial entropion correction using anterior lamellar recession(A... Dear Editor,I read with great interest the article by Gawdat et al^([1]).The authors evaluated the functional and aesthetic outcomes of upper eyelid cicatricial entropion correction using anterior lamellar recession(ALR)combined with procedures addressing the associated conditions including dermatochalasis。 展开更多
关键词 recession LAMELLAR Comment on correction aesthetic appearance Figure subsequent margin TRACHOMA
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Gingival unit transfer using in the Miller Ⅲ recession defect treatment 被引量:1
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作者 Selin Y?ld?r?m Bahar Kuru 《World Journal of Clinical Cases》 SCIE 2015年第2期199-203,共5页
The most significant factor for the success in soft tissue grafts is the synergistic relation between vascular configuration and involved tissues. In the soft tissue graft procedures, site specific donor tissue is ass... The most significant factor for the success in soft tissue grafts is the synergistic relation between vascular configuration and involved tissues. In the soft tissue graft procedures, site specific donor tissue is assumed to have improved potential for function and aesthetic survive at recipient sites. On a clinical level, using site specific gingival unit graft that placed on traditionally prepared recipient site, results in predictable root coverage. In this case report the clinical effectiveness of gingival unit transfer(GUT) technique performed on Miller Ⅲ recession was presented and a similar recession case treated with free gingival graft(FGG) technique for comparison. Probing depth, recession depth, keratinized tissue width and clinical attachment level clinical parameters were measured at baseline and postoperative 8 mo. Percentage of defect coverage was evaluated at postoperative 8 mo. Creeping attachment was assessed at postoperative 1, 3, 6 and 8 mo. The GUT revealed better defect coverage and creeping attachment results than the FGG in the treatment of Miller Ⅲ defects. 展开更多
关键词 AUTOGRAFTING GINGIVA Gingival recession Tooth root TRANSPLANTS
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Relation between early postoperative deviation and long-term outcome after unilateral lateral rectus recession and medial rectus resection for adult exotropia 被引量:1
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作者 Ponnarun Kanjanawasee Pokpong Praneeprachachon Parnchat Pukrushpan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第8期1358-1362,共5页
AIM: To evaluate the relationship between early postoperative deviation and long-term outcome after unilateral recession and resection surgery for adult exotropia, and to evaluate exotropic shift after surgery.METHODS... AIM: To evaluate the relationship between early postoperative deviation and long-term outcome after unilateral recession and resection surgery for adult exotropia, and to evaluate exotropic shift after surgery.METHODS: This was a retroprospective study involving adult patients with exotropia who underwent unilateral recession and resection surgery and were followed up for at least 2 y. The results were evaluated at 2 y and the final visit. Factors influencing a successful outcome were analyzed. Early postoperative deviation at 1 wk was used to evaluate relationship with long-term outcome. The longterm outcome was classified into 3 groups: successful, acceptable, and poor. Successful outcome was defined as a distance deviation between esodeviation 8 prism diopters(PD) and exodeviation 10 PD.RESULTS: Forty-two patients were enrolled. The mean age at surgery was 26 y(range, 15-49 y). The median follow-up period was 30 mo(range, 24-108 mo). Successful outcome was found in 81% of patients at 2 y and in 71% at the final visit. Overcorrection at 1 wk postoperatively was associated with a successful outcome at 2 y. Initial postoperative alignment between orthotropia and esodeviation of 8 PD had the highest chance of a successful outcome(RR=2.2). The mean postoperative exotropic drift was 4.7 PD at the first month and 9.3 PD at 2 y.CONCLUSION: Initial postoperative deviation can predict long-term outcome after unilateral recession and resection surgery for adult exotropia. The most desirable outcome at 1 wk post-operatively was orthotropia to small esodeviation. Most patients have exotropic drift at a subsequent follow-up, especially in the first month after surgery. 展开更多
关键词 EXOTROPIA unilateral surgery recession and resection STRABISMUS
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Comparison of excyclotorsion following graded inferior oblique recession for primary versus secondary inferior oblique overaction 被引量:1
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作者 Donghun Lee Won Jae Kim Myung Mi Kim 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第8期1281-1286,共6页
AIM:To compare the changes in excyclotorsion after inferior oblique(IO)recession in patients with primary and secondary inferior oblique overaction(IOOA).METHODS:We retrospectively analyzed the data obtained from pati... AIM:To compare the changes in excyclotorsion after inferior oblique(IO)recession in patients with primary and secondary inferior oblique overaction(IOOA).METHODS:We retrospectively analyzed the data obtained from patients with IOOA who underwent graded IO recession.The patients were followed up for at least 3 mo after surgery.Fundus photographs were taken preand postoperatively,and the sum of the angles of torsion in both eyes was used to analyze changes in excyclotorsion.Patients were divided into two groups:those diagnosed with primary IOOA were enrolled in the 1’IOOA group,and those diagnosed with secondary IOOA caused by superior oblique palsy(SOP)were enrolled in the 2’IOOA group.Excyclotorsion before and after surgery were compared between the two groups.RESULTS:A total of 78 patients were enrolled in this study:34 eyes in the 1’IOOA group and 44 eyes in the 2’IOOA group.In the 78 patients,torsional angle significantly decreased from 15.31°±7.40°to 12.11°±6.53°after IO recession(P<0.001).Mean preoperative torsional angle was larger in the 2’IOOA group than in the 1’IOOA group(P=0.03).In both groups,excyclotorsion significantly decreased after IO recession(P=0.001 and P<0.001,respectively);however,there was no significant difference in the amounts of changes in excyclotorsion between the two groups.CONCLUSION:Excyclotorsion is significantly larger in secondary IOOA than in primary IOOA,and a significant decrease in the torsional angle occurs after IO recession in both types of IOOA. 展开更多
关键词 inferior oblique overaction inferior oblique recession ocular excyclotorsion STRABISMUS
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Lateral rectus muscle recession and the vertical palpebral fissure height: to do or not to do inter-muscular septum dissection? 被引量:1
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作者 Mohammad Ali Abtahi Alireza Zandi +3 位作者 Eslam Mandegarfard Hamidreza Jahanbani-Ardakani Behzad Mahaki Seyed-Hossein Abtahi 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第6期1053-1055,共3页
In this study, we aimed to evaluate changes of vertical palpebral fissure height(VPFH) after unilateral lateral rectus muscle recession. Twenty-five and twenty-six patients who were candidates for lateral rectus muscl... In this study, we aimed to evaluate changes of vertical palpebral fissure height(VPFH) after unilateral lateral rectus muscle recession. Twenty-five and twenty-six patients who were candidates for lateral rectus muscle recession were assigned into "with" and "without" intermuscular septum dissection study arms. The VPFH was measured at one-day before surgery and in two weeks and three months, postoperatively. Three months after surgery, significant increase of VPFH was observed in both groups(Paired t-test; P=0.005). Also, less widening of VPFH was observed in "with intermuscular septum dissection" group(Change in VPFH in "with intermuscular septum dissection" vs "without intermuscular septum dissection" groups: 0.48 mm vs 1.34 mm; ANCOVA test; P<0.001). However, such results were not observed two weeks post-operatively(Change in VPFH in "with intermuscular septum dissection" vs "without intermuscular septum dissection" groups:-0.28 mm vs 0.28 mm; ANCOVA test; P=0.302). Intermuscular septum dissection is recommended in lateral rectus muscle recession to partially prevent the undesirable increment of VPFH. 展开更多
关键词 intermuscular septum lateral rectus muscle recession vertical palpebral fissure height
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A STUDY ON RECESSION MECHANISM AND REJUVENATION WAYS OF THENORTHEAST OLD INDUSTRIAL BASE
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作者 李诚固 黄岩君 王祁春 《Chinese Geographical Science》 SCIE CSCD 1997年第1期88-94,共7页
Using the theory of regional superiority of forming and developing Of the old industrial bases and theory of transfondng industrial structure, the paper analyses the recession characteristics, reasons and mechanism of... Using the theory of regional superiority of forming and developing Of the old industrial bases and theory of transfondng industrial structure, the paper analyses the recession characteristics, reasons and mechanism of the northest Old industrial base. On the basis of analysing and using the successful experience of other countries, the authors put forward the pattern, goal and way of transforming the northeast old industrial base, combined with the particular national conditions. The poper wants to make the theory and practice system of forming and developing of the world industrial bases more perfect, and provide some experience to promote the systematic development and speed up the industrialized course in the industrial ha of developing countries. 展开更多
关键词 NORTHEAST old INDUSTRIAL base recession MECHANISM INDUSTRIAL structure REJUVENATION
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Comparison of surgically induced astigmatism in patients with horizontal rectus muscle recession
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作者 Harun akmak Tolga Kocatürk Sema Oru Dündar 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第4期709-713,共5页
·AIM: To compare surgically induced astigmatism(SIA)following horizontal rectus muscle recession surgery between suspension recession with both the "hang-back" technique and conventional recession techn... ·AIM: To compare surgically induced astigmatism(SIA)following horizontal rectus muscle recession surgery between suspension recession with both the "hang-back" technique and conventional recession technique.·METHODS: Totally, 48 eyes of 24 patients who had undergone horizontal rectus muscle recession surgery were reviewed retrospectively. The patients were divided into two groups. Twelve patients were operated on by the hang-back technique(Group 1), and 12 by the conventional recession technique(Group 2). SIA was calculated on the 1stwk, 1stand in the 3rdmo after surgery using the SIA calculator.·RESULTS: SIA was statistically higher in the Group 1all postoperative follow-up. SIA was the highest in the 1st wk, and decreased gradually in both groups.·CONCLUSION: The suspension recession technique induced much more SIA than the conventional recession technique. This difference also continued in the following visits. Therefore, the refractive power should be checked postoperatively in order to avoid refractive amblyopia.Conventional recession surgery should be the preferred method so as to minimize the postoperative refractive changes in patients with amblyopia. 展开更多
关键词 recession surgically refractive SUSPENSION operated statistically FIGURE continued preferred POSTOPERATIVE
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Comparison of bilateral/unilateral lateral rectus recession and unilateral recession-resection for intermittent exotropia:a Meta-analysis
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作者 De-Sheng Song Zhi-Jun Chen Jing Qian 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第12期1984-1993,共10页
AIM: To compare the effectiveness of unilateral recession-resection(R&R) and bilateral/unilateral recession(BLR/ULR) for treatment of basic type of intermittent exotropia [IX(T)].METHODS: A comprehensive literatur... AIM: To compare the effectiveness of unilateral recession-resection(R&R) and bilateral/unilateral recession(BLR/ULR) for treatment of basic type of intermittent exotropia [IX(T)].METHODS: A comprehensive literature search was performed using PubMed, EMBASE, and the Cochrane Library, to identify randomized controlled trials and comparative studies regarding the effectiveness of R&R and BLR/ULR for IX(T). Based on which, a Meta-analysis was then performed in terms of long-term success rate, overcorrection rate, and recurrence rate.RESULTS: Nine studies in total satisfy the specified eligibility criteria. BLR is at disadvantage to R&R at a short-term follow-up [<2 y, OR 0.56(0.33-0.94) for success rate; OR 2.11(1.17, 3.81) for undercorrection rate]. However, BLR achieved a higher success rate [OR 2.49(1.61, 3.86)] and a lower undercorrection rate [OR 0.40(0.23, 0.71)], compared to that of R&R at a long-term followup(>2 y). There is no significant difference was found in overcorrection rate, regardless of the length of follow-up time [OR 0.85(0.41, 1.75)]. In the treatment for small-angle IX(T), the final outcome was significantly different between the groups, demonstrating a more successful alignment [OR 0.37(0.18, 0.74)] and a lower undercorrection [OR 3.50(1.28, 7.26)] in the R&R group than in the ULR group. While for moderate-angle IX(T)(20 PD-25 PD), the effectiveness of R&R and ULR is quite equivalent with similar success rate [OR 1.08(0.65, 1.79)] and undercorrection rate [OR 0.89(0.54, 1.48)]. CONCLUSION: As regard to the effect of BLR and R&R, R&R shows an advantage over BLR at short term. But, BLR is more effective in the long term for the basic typeIX(T) in children. R&R surgery should be a better choice for the treatment of small-angle IX(T) of ≤20 PD than ULR. However, both of ULR and R&R are recommended for moderate-angle IX(T) from 20 PD to 25 PD. 展开更多
关键词 INTERMITTENT EXOTROPIA UNILATERAL lateral RECTUS recession recess-resect moderate-angle EXOTROPIA
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Comparison of semilunar coronally repositioned flap with gingival massaging using an Ayurvedic product(irimedadi taila) in the treatment of class-Ⅰ gingival recession: A clinical study
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作者 Amit Kumar Mishra Kanteshwari Kumathalli +4 位作者 Raja Sridhar Rahul Maru Brijesh Mangal Sameer Kedia Ravi Shrihatti 《World Journal of Clinical Cases》 SCIE 2014年第10期534-540,共7页
AIM: To study the comparison in terms of root coverage the effect of gingival massaging using an ayurvedic product and semilunar coronally repositioned flap(SCRF) to assess the treatment outcomes in the management of ... AIM: To study the comparison in terms of root coverage the effect of gingival massaging using an ayurvedic product and semilunar coronally repositioned flap(SCRF) to assess the treatment outcomes in the management of Miller's class Ⅰ gingival recessions over a-6mo period. METHODS: The present study comprised of total of 90 sites of Miller's class-Ⅰ gingival recessions in the maxillary anteriors, the sites were divided into three groups each comprising 30 sites, Group Ⅰ-were treated by massaging using a Placebo(Ghee) Group Ⅱ-were treated by massaging using an ayurvedic product(irimedadi taila). Group Ⅲ-were treated by SCRF. Clinical parameters assessed included recession height, recession width, probing pocket depth, width of attached gingiva, clinical attachment level and thickness of keratinized tissue. Clinical recordings were performed at baseline and 6 mo later. The results were analyzed to determine improvements in the clinical parameters. The comparison was done using Wilcoxon signed rank test. The overall differences in the clinical improvements between the three groups was done using Kruskal-Wallis test. The probability value(P-value) of less than 0.01 was considered as statistically significant.RESULTS: Non-surgical periodontal therapy and gingival massaging improves facial gingival recessions and prevents further progression of mucogingival defects. Root coverage was achieved in both the experimental groups. The SCRF group proved to be superior in terms of all the clinical parameters.CONCLUSION: Root coverage is significantly better with semilunar coronally repositioned flap compared with the gingival massaging technique in the treatment of shallow maxillary Miller class Ⅰ gingival recession defects. 展开更多
关键词 GINGIVAL recession Semilunar FLAPS GINGIVAL massaging NON-SURGICAL
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Systematic review of suicide in economic recession
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作者 Mayowa Oyesanya Javier Lopez-Morinigo Rina Dutta 《World Journal of Psychiatry》 SCIE 2015年第2期243-254,共12页
AIM: To provide a systematic update of the evidence concerning the relationship between economic recession and suicide.METHODS: A keyword search of Ovid Medline, Embase, Embase Classic, PsycI NFO and PsycA RTICLES was... AIM: To provide a systematic update of the evidence concerning the relationship between economic recession and suicide.METHODS: A keyword search of Ovid Medline, Embase, Embase Classic, PsycI NFO and PsycA RTICLES was performed to identify studies that had investigated the association between economic recession and suicide. RESULTS: Thirty-eight studies met predetermined selection criteria and 31 of them found a positive association between economic recession and increased suicide rates. Two studies reported a negative association, two articles failed to find such an association, and three studies were inconclusive. CONCLUSION: Economic recession periods appear to increase overall suicide rates, although further research is warranted in this area, particularly in low income countries. 展开更多
关键词 ECONOMIC recession SUICIDE UNEMPLOYMENT TIME series Systematic REVIEW
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Impact of COVID-19 on G20 countries:analysis of economic recession using data mining approaches
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作者 Osman Taylan Abdulaziz S.Alkabaa Mustafa Tahsin Yılmaz 《Financial Innovation》 2022年第1期2208-2237,共30页
The G20 countries are the locomotives of economic growth,representing 64%of the global population and including 4.7 billion inhabitants.As a monetary and market value index,real gross domestic product(GDP)is affected ... The G20 countries are the locomotives of economic growth,representing 64%of the global population and including 4.7 billion inhabitants.As a monetary and market value index,real gross domestic product(GDP)is affected by several factors and reflects the economic development of countries.This study aimed to reveal the hidden economic patterns of G20 countries,study the complexity of related economic factors,and analyze the economic reactions taken by policymakers during the coronavirus disease of 2019(COVID-19)pandemic recession(2019–2020).In this respect,this study employed data-mining techniques of nonparametric classification tree and hierarchical clustering approaches to consider factors such as GDP/capita,industrial production,government spending,COVID-19 cases/population,patient recovery,COVID-19 death cases,number of hospital beds/1000 people,and percentage of the vaccinated population to identify clusters for G20 countries.The clustering approach can help policymakers measure economic indices in terms of the factors considered to identify the specific focus of influences on economic development.The results exhibited significant findings for the economic effects of the COVID-19 pandemic on G20 countries,splitting them into three clusters by sharing different measurements and patterns(harmonies and variances across G20 countries).A comprehensive statistical analysis was performed to analyze endogenous and exogenous factors.Similarly,the classification and regression tree method was applied to predict the associations between the response and independent factors to split the G-20 countries into different groups and analyze the economic recession.Variables such as GDP per capita and patient recovery of COVID-19 cases with values of$12,012 and 82.8%,respectively,were the most significant factors for clustering the G20 countries,with a correlation coefficient(R2)of 91.8%.The results and findings offer some crucial recommendations to handle pandemics in terms of the suggested economic systems by identifying the challenges that the G20 countries have experienced. 展开更多
关键词 Hierarchical clustering CART Economic recession Data mining COVID-19 G20 countries
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Numerical analysis and evaluation of groundwater recession in a flood detention basin
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作者 XU Jun-xiang WANG Shao-juan +1 位作者 LI Chang-suo XING Li-ting 《Journal of Groundwater Science and Engineering》 2019年第3期253-263,共11页
This study analyzes the groundwater environment in the Yangzhuang flood detention basin in Henan Province,China.A numerical model of groundwater flow is established based on the hydrogeological conditions in the basin... This study analyzes the groundwater environment in the Yangzhuang flood detention basin in Henan Province,China.A numerical model of groundwater flow is established based on the hydrogeological conditions in the basin and changes of groundwater level in the flood detention basin under flood detention and recession conditions.The results show that during flood diversion and storage,the groundwater level in the basin rises,mainly in four flood detention zones,with a maximum rise of 1.0 m.After the floodwater recedes,the groundwater level slowly drops in the detention basin along with flood discharge,finally returning to its original level fifty days later.This study indicates that groundwater recession in the flood detention basin is a slow process,where the rise of groundwater level may cause environmental problems such as soil swamping. 展开更多
关键词 FLOOD DETENTION BASIN NUMERICAL method GROUNDWATER level recession analysis
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On Redefining the Onset of Baseflow Recession on Storm Hydrographs
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作者 R. Pizarro-Tapia F. Balocchi-Contreras +5 位作者 P. Garcia-Chevesich K. Macaya-Perez Per Bro L. León-Gutiérrez B. Helwig R. Valdés-Pineda 《Open Journal of Modern Hydrology》 2013年第4期269-277,共9页
Two methods that define the point of baseflow recession onset were compared using storm hydrograph data for 27 storm events that occurred between 1982-1995 in the Upeo watershed located in the Andes mountain range in ... Two methods that define the point of baseflow recession onset were compared using storm hydrograph data for 27 storm events that occurred between 1982-1995 in the Upeo watershed located in the Andes mountain range in central Chile (Figure 1). Three well-known baseflow recession equations were used to determine whether the method we are proposing here, that defines baseflow recession onset as the third inflection point on the logarithmic graph of the falling limb of the storm hydrograph, more accurately models observed data than the most widely used method that defines baseflow onset as the second inflection point on the same graph. Five time intervals were used to modify the recession coefficient in search of a more accurate fit. Results from the coefficient of determination, standard error, Mann-Whitney U test, and Bland-Altman test suggest that redefining baseflow recession onset via the proposed approach more accurately models baseflow recession behavior. 展开更多
关键词 BASEFLOW recession HYDROGRAPH Separation Hydrologic Modeling recession Analysis BASEFLOW ONSET
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赋范线性空间中Recession锥的表示
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作者 陆竞 《杭州师范学院学报》 1991年第6期20-22,共3页
本文证明了赋范线性空间中闭凸集的Recession锥的表示定理。
关键词 仿射包 相对内核 recession
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Effect of Bilateral Lateral Rectus Recession in Intermittent Exotropia according to the Limbus Insertion Distance
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作者 Manar A. Ghali 《Open Journal of Ophthalmology》 2017年第4期240-248,共9页
Purpose: The aim of this work was the evaluation of the effect of the limbus insertion distance (LID) of the lateral rectus on the surgical results of bilateral lateral rectus recession in intermittent exotropia (IXT)... Purpose: The aim of this work was the evaluation of the effect of the limbus insertion distance (LID) of the lateral rectus on the surgical results of bilateral lateral rectus recession in intermittent exotropia (IXT) in children and adults. Patients and Methods: This retrospective study included 76 patients. The patients were divided into two groups: group I (age 5 - 13 y), group II (>13 y). All the patients had basic type of intermittent exotropia (IXT) and all of them underwent bilateral lateral recessions according to the preoperative angle of deviation. Intraoperatively, the distance of limbus insertion was measured by surgical calipers. The dose response effect was calculated as the difference between the preoperative angle and postoperative angle divided by total amount of recession and cases were followed at 1 month, 3 months, 6 months and 12 months postoperative. Results: The mean LID in group I was (6.2 ± 0.61 mm) and (6.1 ± 0.55 mm) in group II. The mean dose response (MDR) at 1 year postoperative was (2.32 ± 0.25 mm) in group I and (2.26 ± 0.23) in group II. In patients with LID 6.25 mm who had larger mean dose response (2.52 ± 0.15). There was a significant positive correlation between the LR muscle LID and the dose-response effect. Conclusion: There is positive correlation between the LID of the LR muscle and the recession effect in bilateral lateral rectus recession in treatment of IXT. 展开更多
关键词 Intermittent EXOTROPIA LIMBUS INSERTION DISTANCE BILATERAL Lateral Rectus recession
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A Probabilistic Approach for Spring Recession Flows Analysis
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作者 Erick Carlier Jamal El Khattabi 《Open Journal of Modern Hydrology》 2015年第2期11-18,共8页
Spring recession flows are analyzed from a Bayesian point of view. Two general equations are derived and it is shown that the classical formulas of recession flow are particular cases of both equations. It is shown th... Spring recession flows are analyzed from a Bayesian point of view. Two general equations are derived and it is shown that the classical formulas of recession flow are particular cases of both equations. It is shown that most of the recession equations reflect a non-Markovian process. That means that the groundwater storage exhibits a memory effect and that there is a nonlinear relationship between flow and storage. The Bayesian approach presented in this paper makes it possible to give a probabilistic meaning to recession flow equations derived according to a physical approach and can be an alternative to the study of complex reservoir for which the physical processes governing recession flow are unclear. Twelve spring recession flow series are analysed in order to validate the probabilistic approach presented in this paper and a conceptual model of storage-outflow is proposed. 展开更多
关键词 recession SPRING GROUNDWATER BAYESIAN Approach Markovian PROCESS
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Fast Fourier Transform of Multi-Assets Options under Economic Recession Induced Uncertainties
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作者 Philip Ajibola Bankole Olabisi O. Ugbebor 《American Journal of Computational Mathematics》 2019年第3期143-157,共15页
A Fast Fourier transform approach has been presented by Carr & Madan (2009) on a single underlying asset. In this current research paper, we present fast Fourier transform algorithm for the valuation of Multi-asse... A Fast Fourier transform approach has been presented by Carr & Madan (2009) on a single underlying asset. In this current research paper, we present fast Fourier transform algorithm for the valuation of Multi-asset Options under Economic Recession Induced Uncertainties. The issue of multi-dimension in both finite and infinite case of Options is part of the focus of this research. The notion of economic recession was incorporated. An intuition behind the introduction of recession induced volatility uncertainty is revealed by huge volatility variation during the period of economic recession compared to the period of recession-free. Nigeria economic recession outbreak in 2016 and its effects on the uncertainty of the payoffs of Nigeria Stocks Exchange (NSE) among other investments was among the motivating factors for proposing economic recession induced volatility in options pricing. The application of the proposed Fast Fourier Transform algorithm in handling multi-assets options was shown. A new result on options pricing was achieved and capable of yielding efficient option prices during and out of recession. Numerical results were presented on assets in 3-dimensions as an illustration taking Black Scholes prices as a bench mark for method effectiveness comparison. The key findings of this research paper among other crucial contributions could be seen in computational procedure of options valuation in multi-dimensions and uncertainties in options payoffs under the exposure of economic recession. 展开更多
关键词 Fast Fourier Transform (FFT) Multi-Assets Finite and Infinite Dimension of ASSETS Economic recession VOLATILITY Change European OPTIONS
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