On the Polygonal Wear Evolution of Heavy-Haul Locomotive Wheels due to Wheel/Rail Flexibility and Its Mitigation Measures

Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway components.At present,wheel/rail medium-or high-frequency frictional interactions are perceived as an essential reason of the high-order polygonal wear of railway wheels,which are potentially resulted by the flexible deformations of the train/track system or other external excitations.In this work,the effect of wheel/rail flexibility on polygonal wear evolution of heavy-haul locomotive wheels is explored with aid of the long-term wheel polygonal wear evolution simulations,in which different flexible modeling of the heavy-haul wheel/rail coupled system is implemented.Further,the mitigation measures for the polygonal wear of heavy-haul locomotive wheels are discussed.The results point out that the evolution of polygonal wear of heavy-haul locomotive wheels can be veritably simulated with consideration of the flexible effect of both wheelset and rails.Execution of mixed-line operation of heavy-haul trains and application of multicut wheel re-profiling can effectively reduce the development of wheel polygonal wear.This research can provide a deep-going understanding of polygonal wear evolution mechanism of heavy-haul locomotive wheels and its mitigation measures.

Long-Term Oral Corticosteroid-Therapy: Description of the Practice of Adjuvant Measures by Dakar Medical Specialists

Introduction: The extended administration of corticoids by oral way for a length of more than 3 months defines the long-term-corticosteroid-therapy. This one, used in numerous indications, displays most often at the risk of undesirable effects linked sometimes to the habits of prescription of the doctors. Patients and Methods: In order to study the prescription modalities of this treatment, we conducted a cross-sectional, multicentric and descriptive study from June 1st, 2017 to August 1st, 2017, over a period of 2 months. It involved a questionnaire given to medical specialists of all medical specialties and practicing in the University Hospital of Dakar. Results: 170 doctors were interviewed. Dermatologists and internists were mostly found 19.4% and 18.8% or 33% and 34% doctors. Systemic autoimmune diseases alone accounted for 48% of prescription reasons. Prednisone was prescribed in 88% of cases. The immunosuppressive dose of 1 mg/kg was most often prescribed. Practitioners very heterogeneously prescribe most adjuvant measures to prolonged systemic corticosteroid therapy. Thus, the recommendation of a low-sodium diet (38% of physicians), and the systematic prescriptions of proton pump inhibitors (44.7% of physicians) and vitamin-calcium supplementation were frequently performed by physicians (34% of physicians). While the low carbohydrate diet was advocated by less than a quarter of doctors and the prevention of pneumocystosis and osteoporosis were rare (respectively 61% and 52% of prescribers did not). Conclusion: The global analysis of the habits of our medical specialists concerning the use of long-term glucocorticoids reflected a diversity of indications, heterogeneity of practices, with certain habits not in accordance with the usual recommendations.

Trends of Inequalities in the Use of Long-Term Reversible Contraceptives in Burkina Faso between 2010 and 2015

Background: Efforts have been made in Burkina Faso, a French-speaking country, since 2010 to improve healthcare access and provide affordable contraceptive methods to women. With the increasing prevalence of modern contraceptives in Burkina Faso, it is important to examine the socio-demographic factors that contribute to this new pattern of contraceptive use. This study aims to analyze the changes in socio-demographic factors associated with long-term contraceptive use and provide scientific evidence to guide policy development and action planning in family planning. Data and Methods: We utilized data from the 2010 Demographic and Health Survey, which included 17,087 women aged 15 - 49 years, and the 2015 Demographic and Health Module, which included 11,504 women in the same age group. For the analysis of contraceptive use, we focused on women who were in need of contraception (either met or unmet), of reproductive age, non-pregnant, and either married or sexually active but not married. We included users of modern reversible methods and excluded non-users, as well as users of traditional or permanent methods. Results: Our findings revealed a high prevalence of long-term contraceptive use across all categories;however, certain challenges were identified, such as lower levels of information about contraceptive methods among users and the persistence of inequalities. Family planning discussions and partner approval did not influence long-term contraceptive choice. Additionally, some providers selectively offered specific methods based on women’s life course characteristics, such as parity and marital status, despite evidence suggesting that young and nulliparous women can effectively use long-term methods. Conclusion: Given the high effectiveness of long-term contraceptive methods, it is crucial to address barriers that hinder their utilization among young and nulliparous women, as well as those who desire to delay pregnancy. Efforts should focus on improving knowledge and dispelling misconceptions surrounding long-term methods. Providers play a pivotal role in this process by adopting counseling strategies that enhance users’ understanding and facilitate informed decision-making regarding contraceptive options.

A low-cost in-situ CO_(2) sensor based on a membrane and NDIR for long-term measurement in seawater

The multi-point simultaneous long-term measurement of CO_(2) concentration in seawater can provide more-valuable data for further understanding of the spatial and temporal distribution of CO_(2).Thus,the requirement for a low-cost sensor with high precision,low power consumption,and a small size is becoming urgent.In this work,an in-situ sensor for CO_(2) detection in seawater,based on a permeable membrane and non-dispersive infrared(NDIR)technology,is developed.The sensor has a small size(Ф66 mm×124 mm),light weight(0.7 kg in air),low power consumption(<0.9 W),low cost(<US$1000),and high-pressure tolerance(<200 m).After laboratory performance tests,the sensor was found to have a measurement range of(0–2000)×10^(-6),and the gas linear correlation R^(2) is 0.99,with a precision of about 0.98%at a sampling rate of 1 s.A comparison measurement was carried out with a commercial sensor in a pool for 7 days,and the results showed a consistent trend.Further,the newly developed sensor was deployed in Qingdao nearshore water for 35 days.The results proved that the sensor could measure the dynamic changes of CO_(2) concentration in seawater continuously,and had the potential to carry out long-term observations on an oceanic platform.It is hoped that the sensor could be applied to field ocean observations in near future.

Climate change and permafrost stability in the eastern Canada Cordillera:The results of 33 years of measurements

Over the last 33 years,a network of climate stations has been set up at high altitude mountain permafrost sites from Plateau Mountain near Claresholm,Alberta,north to Sheldon Lake on the North Canol Road in the Yukon.Taken together with the data from the US National Weather Service and the Canadian Atmospheric Environment Service,the results indicate a cooling of mean annual air temperature south of Calgary,no significant change in Calgary,a slight warming at Jasper,and a major warming at Summit Lake,west of Fort Nelson.In contrast,the south eastern and central Yukon show only a minor warming trend that lies well within the limits of a sixty-year record measured by the Canadian Atmospheric Environment Service.Along the Mackenzie valley and on the North Slope of Alaska,the mean annual air temperature is rising.Permafrost is aggrading on Plateau Mountain,degrading at Summit Lake,and appears to be stable in southern Yukon and southern Alaska.This is in contrast to the warming occurring on the Arctic coastal plain and along the Mackenzie valley.It therefore appears that changes in climate vary considera-bly from place to place,and even where warming may occur,it may not continue indefinitely.There has been a northward shift of the arctic front due to a weakening of air pressure in the Yukon and Alaska relative to the continental tropical(cT) and maritime polar(mT) air masses to the south.Any actual changes that may be occurring appear to undergo amplification along the Mackenzie valley and Arctic coastal plain and reduction by buffering in the interior Yukon and Alaskan mountains,a result of mi-cro-environmental factors.Continued,careful monitoring of the climate is required and needs to be expanded in the National Parks in the mountains in order to provide data on the changes that may be taking place.Such measurements can provide a sound basis for interpreting ecological and other climate-related data.The existing climate models are not working satisfactorily because we do not know enough about the causes and processes involved in climate change.Improved results can indicate where best to site structures such as pipelines so as to minimize maintenance costs.Models may also help explain why certain areas such as Beringia,which saw reduced climate change,acted as important refugia during the glaciations.

Long-term decay of the water pressure in the osmotic tensiometer

Matric suction is an important state variable required for the assessment of unsaturated soil properties.Tensiometers are commonly used for direct matric suction measurement but have a limited measuring range up to 90 kPa due to the cavitation problem.Osmotic tensiometer(OT)can improve the measuring range of tensiometers by increasing the osmotic pressure of water to avoid the cavitation.However,the long-term water pressure decay that appeared in OTs caused a gradual decrease in their measuring range.In this study,crosslinked poly(acrylamide-co-acrylic acid)potassium salt(PAM-co-PAAK)was used for the preparation of OTs(five in total)to explore the mechanism of water pressure decay of OTs.The maximum water pressure in the OT versus the volume fraction of polymer filled in the OT was described based on the Flory-Huggins polymer theories and validated using WP4C dewpoint hygrometer.The long-term pressure decay of OT-1,OT-2,and OT-3 was observed for 130 d and constant pressures were found for OT-1 and OT-2,indicating that the pressure decay of OT was mainly caused by the stress relaxation of the polymer hydrogels,and standard linear solid(SLS)rheological model was appropriate to fit the decay data.For OT-1,OT-2 and OT-3,the theoretical osmotic pressure that was calculated based on the mass of retrieved polymer from OTs after 130-d pressure observation was higher than the actual osmotic pressure as observed,indicating that polymer leakage cannot explain the pressure decay of the OT.The ultravioletevisible(UVevisible)spectrophotometry examined the change in polymer concentrations in the water containers of OT-4 and OT-5 and demonstrated that there was no increase in polymer leakage during the period of pressure decay of OT-4 and OT-5.As a result,the pressure decay of OT was not caused by polymer leakage.The results of this research suggested that the viscoelastic properties of polymers should be taken into consideration in further OT development.

医护合作多站点宣教模式对高危人工流产患者避孕效果及满意度的影响

目的:探讨医护合作多站点宣教模式对高危人工流产患者避孕知识的掌握、避孕措施的落实及满意度的影响。方法:选取2021年6月至2021年10月本院收治的高危人工流产患者400例为研究对象,随机分为观察组(200例)和对照组(200例)。对照组常规实施流产后关爱,观察组在对照组的基础上,设立计划生育门诊、PAC咨询室、术前宣教室3个宣教站点,实施医护合作多站点宣教模式,两组均随访1年。比较两组避孕知识的掌握、高效避孕措施立即落实、满意度情况,观察两组患者术后1个月、3个月、6个月、12个月的重复流产率、高效避孕措施续用率、随访应答率。结果:与对照组比较,观察组患者对避孕知识的掌握、高效避孕措施立即落实、满意度、高效避孕措施的续用率及随访应答率更优,重复流产率更低,P<0.05,差异均具有统计学意义。结论:医护合作多站点宣教模式可提高高危人工流产患者的避孕节育风险意识,提升高效避孕措施立即落实率和满意度,降低重复流产率的发生,减少流产带来危害,保护其生殖健康。

流产后关爱服务在生育妇女术后落实高效避孕措施中的效果评价

目的探讨流产后关爱服务在生育妇女术后落实高效避孕措施中的效果。方法选取1000例流产妇女为研究对象,随机分为两组,各500例。对照组给予常规护理,实验组给予流产后关爱服务,比较两组的干预效果。结果实验组高效避孕措施使用率高于对照组,重复人工流产率低于对照组(P<0.05);实验组术后避孕措施持续情况优于对照组(P<0.05);实验组医护满意度为98.00%,高于对照组的95.00%(P<0.05)。结论流产后关爱服务在生育妇女术后落实高效避孕措施方面,可极大程度改善流产妇女避孕意识及提升避孕方法使用率,值得借鉴。

人工流产状况分析和流产后关爱服务对女性避孕措施选择的影响

目的调查人工流产现状和流产后关爱(post abortion care,PAC)服务对避孕措施选择的影响,为进一步优化PAC服务的延伸拓展方向提供参考依据。方法对2019年8月至2020年12月笔者医院妇科门诊人工流产的女性实施术前问卷调查和建立标准化PAC服务模式,统计分析其对避孕方式的选择。结果共3000例人工流产患者纳入此研究,问卷调查结果显示人群对避孕知识掌握以及有效避孕措施落实差。实施PAC后避孕措施立即落实率为100%,主要采用的避孕方式为复方口服避孕药(combined oral contraceptive,COC)2295例(76.5%),宫内节育器(intra-uterine device,IUD)577例(19.2%)及避孕套124例(4.1%)。术后1、3、6个月随访中发现宫内节育器放置率逐渐上升,口服避孕药续用率逐渐下降。结论科学系统的优质PAC服务能有效促使高效避孕方法的落实,以减少重复人工流产的发生,保护女性生育健康和提升女性的生活质量。

益阳市未婚青年女性流产后关爱服务回顾性研究

目的探讨未婚青年女性流产后关爱(PAC)服务开展情况,以了解未婚青年女性PAC服务开展过程中存在的问题,探寻解决措施。方法回顾性分析2020年1月至2022年12月在益阳市妇幼保健院计划生育门诊行人工流产的476例未婚青年女性PAC服务登记资料,研究PAC服务落实情况及其存在的问题。结果人工流产前352例(73.95%)未采取避孕措施;人工流产后1、3、6、12个月PAC服务失访例数分别为149、177、169、134例;人工流产后12个月无避孕措施123例(35.04%);PAC服务后无避孕措施、非高效避孕措施占比及非意愿妊娠发生率均低于PAC服务前(P<0.05)。结论PAC服务后的未婚青年女性中仍存在失访率较高、避孕措施落实不够理想等现象,但有效降低了非意愿妊娠发生率。

影响育龄妇女避孕措施选择及效果的因素分析

目的:了解影响育龄妇女避孕方法选择和避孕效果的因素,为提高妇女避孕有效率提供建议。方法:采用整群抽样的方法,对2006年5月～2007年5月在我校附院妇产科门诊,要求人工流产的妇女826例进行横断面调查。结果:年龄、文化程度、婚育情况不同,避孕方法差异有统计学意义(P<0.01)。结论:年龄、文化程度、婚育情况是影响育龄妇女避孕措施选择的主要因素;避孕知识缺乏、侥幸心理、避孕方法不当是影响育龄妇女避孕效果的主要因素。重视避孕,正确使用避孕方法是提高育龄妇女避孕有效率的重要方面。

农村育龄妇女生殖道疾病和避孕措施调查

目的调查农村育龄妇女常见生殖道疾病的现患率和避孕措施及影响因素,为计生服务和生殖道疾病的防治提供依据。方法按经济水平进行分层整群随机抽样,对抽中的育龄妇女开展流行病学调查和实验室检查,采用SPSS软件分析资料。结果农村育龄妇女以避孕环节育为主,低年龄高学历和经济发达地区的妇女容易使用避孕环和避孕套,高年龄低学历和经济欠发达地区的妇女使用绝育术和其他方式避孕;高龄妇女易患子宫肌瘤和其他生殖道疾病。经济发达地区妇女生殖道疾病以阴道炎和其他疾病为主,而经济欠发达地区以宫颈炎和子宫肌瘤为主。结论与城市相比,农村育龄妇女的节育模式还没有明显变化,生殖道疾病的患病率不容乐观,应该适当调整计生服务模式,并加大对各种生殖道疾病的防治工作力度。

已婚育龄妇女避孕措施变化趋势分析

目的：了解已婚育龄妇女避孕措施的变化趋势，为指导计划生育服务工作提供科学依据。方法：收集1983～2005年苏州市已婚育龄妇女避孕方法的资料，并用统计软件对其变化趋势进行了分析。结果：已婚育龄妇女节育率在88．38％～92．94％范围波动，长效避孕措施现用率从75．19％下降至71．27％，而短效避孕措施从12．86％上升至17．11％。宫内节育器的现用率从50．09％上升到66．50％；避孕套从1．94％上升到14．21％；其他避孕方法的现用率均呈下降趋势，其中女性绝育现用率从24．42％下降到4．50％。结论：节育率维持在较高水平；长效避孕措施现用率下降而短效避孕措施现用率上升；避孕方法使用趋于多样化，需要提供满足个性化需求的指导和服务。

未婚大学生性行为及避孕方式调查

目的了解未婚大学生性行为及避孕方式现状,为高校开展性健康教育提供理论基础。方法采用《大学生性行为调查问卷》对黑龙江省三所综合性大学1 500名大学生进行无记名问卷调查。结果约40%以上的学生不反对性解放,30%学生认为在校期间可以同居或有婚前性行为,其中23%学生有婚前性行为,但只有15%的学生清楚什么是安全的避孕措施。结论高校、家庭和社会需要给予大学生全面的性健康教育包括性安全教育。

深圳市流动人口避孕节育个性化需求现状调查

目的：了解现居住在深圳市的流动人口避孕现状及对个性化避孕节育的需求，探索建立一套适宜流动人口的个性化避孕节育新技术新方法的方案及最佳推广模式。方法：描述性流行病学研究方法，采用定性访谈和定量调查相结合的方法。对象为现居住在深圳市的流动人口（包括已婚和未婚有性生活的）4066例，年龄在15—47岁，未采取长效避孕措施。结果：通过基线调查现居住在深圳市的流动人口70．3％来自农村，属于“三低”人群，即低年龄、低文化、低收入。流动人口对生殖健康、避孕、节育的知识需求强烈，是值得重视和关注的人群。结论：针对流动人口有必要提供个性化服务及深层次的知情选择，根据不同年龄群体避孕、意愿，以及避孕、生殖的相关知识了解的现状和影响因素，开展个性化的适宜避孕节育技术推广工作，提升流动人口的生殖健康水平。

泰安市1013例人工流产妇女的调查统计分析

目的调查人工流产妇女的各种可能原因,为降低居高不下的人工流产水平提供依据。方法设计调查问卷,对1013例人工流产妇女各种人口学及相关行为分布进行统计分析、整理以得到相关资料。结果人工流产妇女年龄构成较低,未婚占相当比重。结论应大力开展生殖健康工作,以保护育龄妇女身心健康。

输卵管内径测量在输卵管节育栓研制中的应用价值

目的:通过对输卵管内径的测量及分析,为输卵管节育栓的研制提供基础数据。方法:子宫输卵管数字减影血管造影(DSA)检查100例,应用GE公司AW4.3工作站进行输卵管内径测量和数据频数分析。结果:输卵管内口内径1.07±0.48mm,0.60～1.39mm频率最高(74.0%);间质部中段内径0.50±0.22mm,0.30～0.69mm频率占79.5%;间质部远端内径0.32±0.12mm,0.20～0.49mm频率占89.0%;峡部内径0.46±0.28mm,0.20～0.79mm频率占89.5%。结论:输卵管内径平均值及频数分布对输卵管节育栓的大小、形状的研制具有重要意义。

流产后关爱服务患者选用避孕措施的临床研究

目的探讨流产后关爱（PAC）患者选取避孕措施的现状,优化PAC服务流程。方法选取2013年1月~2014年2月因意外妊娠自愿到本院行人工流产终止妊娠的1013例孕龄妇女作为研究对象,患者全程PAC服务后自愿选择避孕措施的一种,根据选择结果分为4组。A组为皮下埋植法,立即使用29例;B组为短效口服避孕药,立即使用717例;C组为宫内节育器,立即使用201例;D组为避孕套避孕,立即使用66例。分析各组2年内的构成比变化,比较各组避孕后的再孕发生率、不良反应发生率、提前终止率及满意率。结果 PAC服务后,A组立即使用的比例为2.9%,2年后为5.9%;B组立即使用的比例为70.8%,2年后为19.5%;C组立即使用的比例为19.5%,2年后为33.4%;D组立即使用的比例6.5%,2年后为41.3%。A组的不良反应发生率最高,满意率最低;B组的提前终止率最高;C组的满意率最高;D组的再孕率最高。各组比较差异有统计学意义（P〈0.05）。结论 PAC服务后患者能自愿选择有效避孕措施,其中皮下埋植存在认知度低、满意率低等问题。PAC 3个月后,避孕套仍是大部分患者的首选,但具有意外妊娠率较高的缺点,因此需优化PAC随访流程。

严肃的气球——西藏牧区妇女生育变迁

节育措施在西藏传统的游牧社区并不普及,这在一定程度上也是传统社区育龄妇女多产并形成以扩大家庭为典型家庭结构特征的间接原因之一。20世纪80年代以来,随着国家计划生育政策的实施,节育措施在牧区也逐渐被推广和应用,牧区妇女的生育观念、生育行为逐渐发生变化,呈现出育龄妇女生育胎数逐步减少、家庭结构转向以小规模家庭为主的趋势。

常用节育措施并发症治疗成本的影响因素

调查了四项节育措施并发症治疗的直接成本和间接成本,对其影响因素进行了分析。结果表明:不同措施、不同种类并发症治疗成本不同,其中以男、女性绝育术并发症治疗成本最高,主要是感染引起的并发症。各种并发症治疗成本随年代而降低;另外,治疗成本受就诊次数、家庭在村里相对收入水平、家距乡镇距离、1994年村人均纯收入、职业层次、妇幼保健工作开展情况、有无节育保险的影响。为此提出减少并发症,降低其治疗成本的建议。