Patterns of tree buttressing at Lawachara National Park, Bangladesh

We describe patterns of buttress formation and development in eleven tree species at Lawachara National Park, Bangladesh. Forty-five percent of trees of these 11 species had buttresses. Artocarpus chaplasha Roxb. showed maximum （87%） buttress formation, whereas Alstonia scholaris （L.） R. Br. did not show any buttress. Buttresses were recorded in 20%-40% of trees of six species and 40%-60% of trees in three species. Mean length and height of buttress varied among the species and ranged from 0.37-4.37 m and 0.71-2.13 m, respectively. Buttress height, mean buttress length, total buttress length, and total length plus length of secondaries increased with DBH （diameter at breast height） and tree height. Buttress number did not increase with DBH or tree height. Under-storey and mid-canopy trees produced less developed buttresses than did emergent trees （p〈0.01）. Wood density showed moderate effects on buttress characters （p〈0.05）, while the slope of the land did not. Canopy category was a primary regulating factor for tree buttressing, suggesting that buttresses are mechanical adaptations of trees to counter physical stresses.

Numerical parametric study on the influence of location and inclination of large-scale asperities on the shear strength of concreterock interfaces of small buttress dams

When assessing the sliding stability of a concrete dam,the influence of large-scale asperities in the sliding plane is often ignored due to limitations of the analytical rigid body assessment methods provided by current dam assessment guidelines.However,these asperities can potentially improve the load capacity of a concrete dam in terms of sliding stability.Although their influence in a sliding plane has been thoroughly studied for direct shear,their influence under eccentric loading,as in the case of dams,is unknown.This paper presents the results of a parametric study that used finite element analysis(FEA)to investigate the influence of large-scale asperities on the load capacity of small buttress dams.By varying the inclination and location of an asperity located in the concrete-rock interface along with the strength of the rock foundation material,transitions between different failure modes and correlations between the load capacity and the varied parameters were observed.The results indicated that the inclination of the asperity had a significant impact on the failure mode.When the inclinationwas 30and greater,interlocking occurred between the dam and foundation and the governing failure modes were either rupture of the dam body or asperity.When the asperity inclination was significant enough to provide interlocking,the load capacity of the dam was impacted by the strength of the rock in the foundation through influencing the load capacity of the asperity.The location of the asperity along the concrete-rock interface did not affect the failure mode,except for when the asperity was located at the toe of the dam,but had an influence on the load capacity when the failure occurred by rupture of the buttress or by sliding.By accounting for a single large-scale asperity in the concrete-rock interface of the analysed dam,a horizontal load capacity increase of 30%e160%was obtained,depending on the inclination and location of the asperity and the strength of the foundation material.

胫骨平台后柱骨折应用Buttress钢板固定的临床效果

目的探讨胫骨平台后柱骨折应用Buttress钢板固定的临床效果。方法选取我院2014年3月至2016年10月收治的31例累及胫骨平台后柱骨折患者作为研究对象,均给予后侧入路切开复位后支撑钢板内固定治疗。回顾性分析其临床治疗过程和结果。结果 31例患者均随访(12.52±2.62)个月。所有患者均获得骨性愈合,其平均骨折愈合时间为(4.12±1.33)个月。所有患者的治疗效果为优17例,良11例,可2例,差1例,优良率为90.32%。31例患者中,有1例因腘动脉血栓探查修复及小腿减压术后肢体功能不全而发生并发症。结论胫骨平台后柱骨折应用Buttress钢板固定,可获得良好的临床效果,还可减少并发症,值得临床推广应用。

股骨髁支持钢板治疗股骨远端骨折

目的:探讨应用股骨髁支持钢板内固定治疗股骨远端骨折的方法和临床疗效。方法:2001年9月至2010年9月对75例股骨远端骨折进行修复重建。其中男56例,女19例;年龄年龄19～67岁,平均37.5岁。闭合性骨折61例,开放性骨折14例。骨折按AO/ASIF分类,A型骨折28例,B型骨折14例,C型骨折33例。均行切开复位,股骨髁支持钢板内固定,对骨缺损较大者行一期植骨,术后行康复治疗。结果:患者均获得随访,随访时间8～56个月,平均15个月,骨折均愈合。按Merchant功能评定标准评定,优38例,良32例,可4例,差1例,优良率93.3%。结论:严格遵循手术治疗原则,采用股骨髁支持钢板内固定治疗股骨远端骨折,固定可靠,操作简单,疗效肯定。

数字化Buttress钢板固定术治疗胫骨平台后柱骨折的效果分析

目的:探讨用切开复位数字化Buttress钢板固定术治疗胫骨平台后柱骨折的效果。方法:选择2019年6月至2020年6月期间湛江中心人民医院收治的36例有明确手术指征的新鲜闭合性胫骨平台后柱骨折患者作为研究对象。随机将其分为对照组(n=18)和试验组(n=18)。对对照组患者进行常规的切开复位钢板固定术,对试验组患者进行切开复位数字化Buttress钢板固定术,然后比较两组患者手术的时间、术中的出血量、术后发生并发症的情况、术后美国纽约特种外科医院(HSS)膝关节评分及36项健康状况调查问卷(SF-36)的评分。结果:两组患者均手术成功,其术后均未出现切口感染、皮肤坏死、内固定物断裂、松动、胫骨平台塌陷、移位等并发症。试验组患者手术的时间短于对照组患者,其术中的出血量少于对照组患者,差异有统计学意义(P<0.05)。两组患者术后10个月的HSS膝关节评分及SF-36评分相比,差异无统计学意义(P>0.05)。结论:用切开复位数字化Buttress钢板固定术治疗胫骨平台后柱骨折的效果显著,能缩短患者手术的时间,减少其术中的出血量,且其术后的并发症较少,手术的安全性较高。

Buttress与空心钉治疗旋后外旋Ⅳ度踝关节骨折的效果比较

目的比较Buttress与空心钉治疗旋后外旋Ⅳ度踝关节骨折(AF)的效果。方法回顾性选取2020年1月至2023年1月在本院诊治的90例旋后外旋Ⅳ度AF患者为研究对象,按照手术方法的不同分为A组(n=40)、B组(n=50)。A组给予空心钉固定治疗,B组给予Buttress固定治疗。比较两组患者的手术指标、术后3个月的骨折愈合情况、并发症发生率、美国足踝骨科协会(AOFAS)优良率以及术前、术后3个月的AOFAS评分。结果B组手术时间、术中出血量均显著高于A组(P<0.05),住院时间、下地行走时间及完全负重时间均显著低于A组(P<0.05)。两组患者术后3个月的骨折愈合优良率及并发症发生率比较差异均无统计学意义(P>0.05)。与术前比较,两组患者术后3个月的AOFAS评分显著升高(P<0.05),且B组AOFAS评分及其优良率均显著优于A组(P<0.05)。结论空心钉与Buttress治疗旋后外旋Ⅳ度AF患者,在促进骨折愈合、减少并发症方面的效果相当;与空心钉治疗比较,Buttress治疗更有助于促进患者术后恢复,恢复患者正常关节功能,但后者具有手术操作时间长、出血量大的不足。

Design and Strength Analysis of A Spherical Connector for Lifting Subsystem in Deep Sea Mining System

A flexible connector of lifting pipes in a deep sea mining system is designed. The buttress thread （ based on API standard） is used and foreign experience in connector design is referred to. With this kind of connector, the lifting pipe wiU only bear the axial force, free of moment. The strength of the connector is analyzed in detail, including the connecting strength of the buttress thread, the dynamic load of the pipe system, pressures inside and outside of the pipe, the lateral stress of the pipe wall and so on. Especially, a geometric model is built for 3-D contact stress analysis. The distribution graph of contact stress is presented. It is indicated that the strength of the spherical connector meets the demand.

Trochanteric Buttress Plate Combined with Proximal Femoral Nail for Unstable Intertrochanteric Fractures. [Innovative Technique]

Introduction: Proximal femoral nail is a better choice of implant for the treatment of an unstable trochanteric fracture, however it is associated with screw migration and cutout because of greater trochanteric comminution and coronal split. This study is to evaluate the results of Trochanteric Buttress Plate (TBP) combined with PFN in an unstable IT fractures for buttressing lateral wall and reinforcing fixation. Materials and Methods: We carried out a consecutive study of 32 patients of Unstable intertrochanteric fracture femur with lateral wall comminution. It was studied at Ashwini Sahakari Rugnalaya and Sanshodhan Kendra Solapur India and Government medical college Chandrapur India from April-2015 to December-2017 using innovative Trochanteric buttress plate along with PFN. Eighteen male and fourteen female in the age group of 55 to 80 years were included in the study. There were 26 cases of A3 and six cases of A2 were fixed by PFN combined with trochanteric buttress plate to augment the comminuted lateral wall. Results: The bone healing is observed in all the cases in the mean period of 12.6 weeks. Four patients developed complications, including lateral migration of neck screws (n = 2), superficial infection (n = 2). Patients were followed up for a mean of 10.6 months. At the end of follow-up the Salvati and Wilson hip function was 36 (out of 40) in 87.5% of patients [twenty eight patients]. The clinical, radiological and functional outcomes were found to be satisfactory. Conclusion: The stabilization of lateral trochanteric wall with trochanteric buttress plate restores anatomy, increases the stability of construct and prevents inherent complication of screw migration and cutout.

Buttress螺钉固定治疗踝关节旋后-外旋型Ⅳ度内踝骨折的临床效果

目的探讨Buttress螺钉固定治疗踝关节旋后-外旋型Ⅳ度内踝骨折的临床效果。方法选择在本院接受治疗的26例踝关节骨折中旋后-外旋型Ⅳ度伴内踝骨折的患者为研究对象,均采用Buttress螺钉技术固定内踝骨折。评估患者的临床疗效。结果术后患者均获得随访,平均时间(12.48±5.62)个月。所有伤口Ⅰ期愈合,无螺钉松动、断裂,无骨折移位及畸形愈合。末次随访AOFAS踝-后足评分(89.60±3.60)分,VAS评分(2.01±1.20)分。结论 Buttress螺钉技术固定内踝骨折块稳定,软组织损伤较小,骨折愈合时间短,临床效果满意。

Buttress钢板在踝关节垂直型骨折中的应用研究

目的回顾性评估Buttress钢板在踝关节垂直型骨折中的应用效果。方法选取我院2020年3月—2022年9月收治的88例踝关节垂直型骨折患者为研究对象,其中男52例,女36例;年龄(58.45±10.62)岁;伤后至手术时间(5.11±1.02)天;摔伤49例,扭伤19例,车祸伤20例。均依据病史、X线和CT影像学检查诊断为内踝骨折,骨折线垂直走形,给予切开复位后Buttress钢板(或联合其他钢板)内固定治疗。回顾性分析其临床治疗过程和结果,按照AOFAS踝-后足评分评定。结果88例术后患者均获得随访,随访时间(12.44±0.71)个月。所有患者均获得骨性愈合,其中延迟愈合7例,无不愈合患者。并发创伤性关节炎者2例,伤口Ⅰ期愈合者85例,并发伤口感染未能I期愈合者3例。无螺钉松动、断裂,骨折无移位,无畸形愈合,末次随访AOFAS踝-后足评分为(90.54±5.12)分,治疗效果为优80例,良6例,可0例,差2例,治疗优良率为97.73%。结论踝关节垂直型骨折应用Buttress钢板固定,可获得良好的治疗效果,术后踝-后足稳定性好、并发症少、固定牢靠,建议推广应用。

Usage of buttress plate internal fixation associated with autografting of fibula and iliac bone for the treatment of distal femoral C_3 type fracture

To assess the effect of using buttress plate associated with antografting of fibula and iliac bone for the treatment of distal femoral C3 type fracture.Methods Seventeen cases of distal femoral C3 type fracture using buttress plate associated with antografting of fibula and iliac bone were analyzed retrospectively.Results All cases were followed up for an average of 24 months（8～55 months）.The average time of octets bridge forming were 4 months（3～5 months） while the average time for bone union were 8 months （6～14 months）.According to Shelbourne rating system,result of all 18 cases were excellent and no malunion,infection were found.Conclusion Buttress plate associated with antografting of fibula and iliac bone is an effective alternative for the treatment of distal femoral C3 type fracture.It can provide more stable fixation to the bone and earlier functional exercises can be achieved.5 refs,3 figs,1 tab.

Metapodials of ancient bison(Bison priscus)of northeast Russia:“stress markers,”sex and withers height

A total of 175 metapodials(MP)of Pleistocene and early Holocene bison(Bison priscus Boj.)from the vast area of northeast Russia were studied.MP were attributed to males and females both visually and statistically.Data on the withers height of bison from northeast Russia are provided.Stress markers were recorded,including so-called“buttresses.”With rare exceptions,stress markers were not of a pathological nature.The origin and de­velopment of the buttresses are age-related;their prevalence in bison females can be considered as the response to an increased load during pregnancy.Changes in the periosteum,found in males,are related to their great­er activity.Buttresses are also well developed on metatarsals of the red deer and the elk;they are less developed in reindeer and not found in giant deer.A relationship among stress markers,locomotion and the environment is established.Possible peculiarities of the Rauchua River bison locomotion are discussed.

Buttress trees in a 20-hectare tropical dipterocarp rainforest in Xishuangbanna, SW China

Aims buttresses are prevalent and are important to many ecological processes in tropical rainforests but are overlooked in many rainforest studies.based on a buttress survey in a 20-hectare plot,this study aims to answer the following questions:(i)is buttress forming a fixed species characteristic?(ii)is there any phylogenetic signal for buttress forming across a broad taxonomic scale?(iii)is buttress form-ing an inherent feature or simply induced by environmental factors,and how is this relevant to the size of the tree?Methods We surveyed buttresses for all 95940 trees with diameter at breast height(DbH)≥10 mm in a 20-ha tropical dipterocarp rainforest in Xishuangbanna,sW China.The occurrence of buttresses was compared across different taxa and across different tree-size classes.a phylogenetic analysis was conducted among buttressed and non-buttressed species in order to understand the evolutionary background of buttress formation.Important Findings This preliminary study showed that buttress trees are very abundant(making up 32%of trees with≥100 mm DbH)in this 20-ha tropical rainforest situated at the northern edge of the tropics.Fifty-one percent of the 468 tree species in the plot had stems that produced buttresses.large trees were more likely to develop buttresses than smaller ones.We found that although buttress formation is not a fixed species characteristic,there is a strong phylogenetic signal for buttress formation in larger species.

后内侧倒L形切口Buttress钢板内固定治疗胫骨平台后柱骨折疗效观察

目的探讨后内侧倒L形切口Buttress钢板内固定治疗胫骨平台后柱骨折的临床疗效。方法回顾性分析自2013-02—2019-06诊治的13例胫骨平台后柱骨折,采用后内侧倒L形切口显露后柱骨折块,骨折复位后用1或2枚Buttress钢板对骨折块进行固定。结果13例均获得随访,随访时间平均16(6~24)个月。随访期间未出现深部感染、内固定失效、骨折不愈合等并发症。骨折愈合时间11~16周,平均12.3周。末次随访时伸膝角度为-5°~5°,平均2.7°;屈膝角度120°~135°,平均126.2°。末次随访时膝关节功能Rasmussen评分平均24.3(17~28)分,其中优5例,良6例,可2例。结论采用后内侧倒L形切口Buttress钢板内固定治疗胫骨平台后柱骨折具有显露安全且充分、骨折复位固定操作简便、创伤小、固定可靠等优点,可取得满意的疗效。

Outcome of buttress plate-nail construct used for reconstruction of broken lateral wall in intertrochanteric fractures

Purpose:Intramedullary implants are well accepted fixation of all types of intertrochanteric(IT)frac-tures,both stable and unstable types.Intramedullary nails have an ability to effectively support the posteromedial part,but fail to buttress the broken lateral wall requiring lateral augmentation.The aim of this study was to evaluate the outcome of proximal femoral nail augmented with trochanteric buttress plate for broken lateral wall with IT fractures,which was fixed to the femur through hip screw and anti-rotation screw nail.Methods:Of 30 patients,20 had Jensen-Evan typeⅢand 10 had type V fractures.Patients with IT fracture of broken lateral wall and aged more than 18 years,in whom satisfactory reduction was achieved by closed methods,were included in the study.Patients with pathologic or open fractures,polytrauma,prior hip surgery,non-ambulatory prior to surgery,and those who refused to participate were excluded.The operative time,blood loss,radiation exposure,quality of reduction,functional outcome,and union time were evaluated.All data were coded and recorded in Microsoft Excel spread sheet program.SPSS 20.0 was used for data analysis and normality of the continuous data was checked using Kolmogorv Smirnov test.Results:The mean age of patients in the study was 60.3 years.The mean duration of surgery(min),mean intra-operative blood loss(mL)and mean number of exposures were 91.86±12.8(range 70-122),144.8±3.6(range 116-208),and 56.6(range 38-112),respectively.The mean union time was 11.6 weeks and the mean Harris hip score was 94.1.Conclusion:Lateral trochanteric wall in IT fractures is significantly important,and needs to be recon-structed adequately.Nail-plate construct of trochanteric buttress plate fixed with hip screw and anti-rotation screw of proximal femoral nail can be successfully used to augment,fix or buttress the lateral trochanteric wall giving excellent to good results of early union and reduction.

The Belt and Road Initiative and International Law:Viewed from the Perspective of the Supply of International Public Goods

The international community is facing the dilemma of an insufficient supply of public goods due to the conjunction of various forces and factors including the profound impact of the economic crisis,increased trade protectionism,changes in the global governance system and the impact of the Covid-19 pandemic.The Belt and Road Initiative(BRI)is a non-rivalrous and non-excludable public good provided to the international community by China as a responsible major country in the new era of historical development.International law has an important role in promoting and guaranteeing the supply of international public goods(IPGs).Since the implementation of the Belt and Road Initiative,the international governance environment has changed dramatically,with the rule of law being the basic premise and important guarantee of the long-term and smooth implementation of the BRI.In pursuing the BRI,buttressed as it is by the rule of law,China should pay attention to diversified governance based on a combination of international soft and hard law and make judicious use of existing bilateral,regional and multilateral international legal mechanisms.In addition,China must also pay close attention to the latest developments in international economic and trade rules and must innovate and improve its ability to supply rules for investment,trade liberalization,etc.Buttressed by international law,the BRI should focus not only on recent concrete initiatives in trade and investment liberalization,but also on the long-term planning and sustainable development of institutional supply,so as to realize the vision and goals of the BRI.

Surgical management of zygomatic complex fractures in a major trauma centre

Aim: To analyse the epidemiology, aetiology, and surgical management of zygomatic complex (ZMC) fractures in our major trauma centre, and to compare the number and location of fixation points and surgical access in our patient cohort with the literature. Methods: Retrospective analysis of all operative cases (Open Reduction and Internal Fixation) of zygomatic complex fractures over a one year period (2016). Results: A greater proportion of patients in our cohort (54%) were treated with one-point fixation compared to the literature, with the zygomaticomaxillary (ZM) buttress being the most popular fixation point (90%). ZM buttress and frontozygomatic (FZ) suture were the commonest choices for two-point fixations (70%). Buccal sulcus incision was used for ZM access in all cases. For FZ access, upper blepharoplasty incision was the most common (56%). For infra-orbital margin access, transconjunctival incision was the most common (75%). There was no significant association between number of fixation points and presence of associated injuries, impact of injury, or time to operation. There were no post-operative complications. Conclusion: A greater proportion of patients in our cohort were successfully treated with one point fixation compared to the literature, and fewer patients underwent orbital floor exploration and repair in our cohort compared to the literature. This study highlights the ongoing variation in the surgical management of ZMC fractures.