Laser Peening Process and Its Impact on Materials Properties in Comparison with Shot Peening and Ultrasonic Impact Peening

The laser shock peening (LSP) process using a Q-switched pulsed laser beam for surface modification has been reviewed. The development of the LSP technique and its numerous advantages over the conventional shot peening (SP) such as better surface finish, higher depths of residual stress and uniform distribution of intensity were discussed. Similar comparison with ultrasonic impact peening (UIP)/ultrasonic shot peening (USP) was incorporated, when possible. The generation of shock waves, processing parameters, and characterization of LSP treated specimens were described. Special attention was given to the influence of LSP process parameters on residual stress profiles, material properties and structures. Based on the studies so far, more fundamental understanding is still needed when selecting optimized LSP processing parameters and substrate conditions. A summary of the parametric studies of LSP on different materials has been presented. Furthermore, enhancements in the surface micro and nanohardness, elastic modulus, tensile yield strength and refinement of microstructure which translates to increased fatigue life, fretting fatigue life, stress corrosion cracking (SCC) and corrosion resistance were addressed. However, research gaps related to the inconsistencies in the literature were identified. Current status, developments and challenges of the LSP technique were discussed.     

基于消除鄱阳湖生态经济区开发过程中环境保护成长上限的管理对策探讨

2009年鄱阳湖生态经济区开发上升为国家战略,鄱阳湖生态经济区的发展成为江西实现中部崛起的重要举措。但值得关注的是,经济区生态系统的保护、环境问题的改善必须放在重要地位,必须认真分析开发过程中遇到的地表及尘土污染防治差额、水资源污染防治差额、执法效能差额、环境管理与监控差额等环境保护的成长上限问题。为此,笔者根据成长上限的消除原理,提出管理对策。     

Encounters with older lesbians in psychiatric practice

This paper starts from the feminist perspective that the problems experienced by older lesbians need to be understood in their political and socio-cultural context. Given that we live in a society that pathologizes sexual activity beyond the reproductive years and lesbianism at any age, and which labels old people as asexual, lesbians frequently present to practitioners in unorthodox ways. This is perhaps because internalized oppression and fears of being labelled ‘sick’, ‘deviant’, ‘sexless’, and even ‘psychogeriatric’ silence them. Case material is presented in an attempt to illustrate an eclectic basis for practice which reflects the experience of older lesbians. Despite the traditional view that older people are unsuitable for the psychotherapies and respond better to more ‘medical’ therapies (drugs, electroconvulsive therapy, etc.), this paper demonstrates that therapy can be helpful and relevant to older lesbians when the therapist does not construct the patient's lesbianism as a basic problem.     

Theoretical ionization and capture cross sections for DNA nucleobases impacted by light ions

Abstract

Purpose: Although DNA lesions are considered of prime importance for describing the post-irradiation cellular survival, they still remain rarely studied on both experimental and theoretical sides. Under these conditions, we here propose different theoretical models for predicting the single ionization and single capture total cross sections for DNA bases impacted by protons.

Material and methods: Three theoretical approaches are developed: a first classical one based on a classical trajectory Monte Carlo (CTMC) model and two quantum mechanical ones, namely, a Coulomb Born (CB1) and a continuum-distorted wave eikonal-initial-state (CDW-EIS) model.

Results: Ionization and capture processes induced by protons on DNA bases (adenine, cytosine, thymine and guanine) are here studied in terms of total cross sections.

Conclusions: A very good agreement is obtained between the different models at high enough impact velocities but discrepancies are observed between them at low impact energies (E_i ≤ 100 keV). Furthermore, it is shown that the theoretical cross sections underestimate the rare existing experimental data in particular for adenine and thymine whereas a reasonable agreement is found for cytosine.     

A note on calculating asymptotic confidence intervals for the adjusted risk difference and number needed to treat in the Cox regression model

Recently, Laubender and Bender (Stat. Med. 2010; 29: 851–859) applied the average risk difference (RD) approach to estimate adjusted RD and corresponding number needed to treat measures in the Cox proportional hazards model. We calculated standard errors and confidence intervals by using bootstrap techniques. In this paper, we develop asymptotic variance estimates of the adjusted RD measures and corresponding asymptotic confidence intervals within the counting process theory and evaluated them in a simulation study. We illustrate the use of the asymptotic confidence intervals by means of data of the Düsseldorf Obesity Mortality Study. Copyright © 2013 John Wiley & Sons, Ltd.     

El impacto de la crisis en la relación entre vivienda y salud. Políticas de buenas prácticas para reducir las desigualdades en salud asociadas con las condiciones de vivienda

Housing conditions can impact on physical and mental health through 4 interrelated dimensions: 1) the home (the emotional housing conditions), 2) the physical housing conditions, and 3) the physical environment, and 4) the social (community) environment of the neighborhood where the house is located. In Spain, the use of the construction market as an engine for economic growth and the promotion of private property as the main type of housing tenure has led to the use of housing as a speculative good instead of its being considered a first-necessity good. While Spain is the Organisation for Economic Co-operation and Development (OECD) country with the largest housing stock per inhabitant, this stock is highly underutilized, thus excluding the most deprived sector of the population from access to housing. The impact of the current economic crisis on housing has mainly been due to a reduction in household income, which has increased the number of families or persons struggling to cover their housing costs or being evicted. Evidence indicates that this type of problem has a negative impact on health, especially on mental health, but financial problems also make it difficult to meet other basic needs such as eating. There are several instruments to reduce the impact of the economic crisis, such as debt financing or deed of assignment in payment. In the long-term, the creation of a social housing stock should be promoted, as well as rental assistance mechanisms.     

COVID-19 vaccination: The impact on the selection criteria of the convalescent plasma donors

Clinical management protocols for COVID-19 are evolving rapidly as more information about the epidemiology and pathophysiological changes in COVID-19 become available. However, no definite treatment of COVID-19 has been found till date. The COVID-19 convalescent plasma (CCP) therapy has emerged as an important investigational therapy in the management of COVID-19 patients. Additionally, the regulatory agencies, in particular, the Indian blood transfusion council must release some interim recommendations for the blood centres on the CCP blood donor eligibility criteria after COVID-19 vaccination. More clinical trials are needed to know the efficacy of the CCP harvested from COVID-19 recovered individuals who have been vaccinated against those COVID-19 recovered individuals who are not vaccinated to understand the vaccine impact on the IgG titres of anti-SARS-CoV-2 antibodies.     

一清胶囊在肺结核合并革兰阴性菌感染中的成本-效果分析

目的 对内毒素检测阳性的肺结核患者实施不同治疗策略,分析不同策略的成本-效果,为利用一清胶囊治疗革兰阴性菌(G)感染提供理论和经济学依据.方法 120例内毒素检测阳性的肺结核患者随机分为治疗组和对照组,治疗组同时接受一清胶囊联合常规的抗菌治疗,对照组仅进行常规的抗菌治疗.分别记录患者的CRP的复常时间、体温复常时间、内毒素转阴时间以及影像的感染情况改善程度进行成本-效果分析.结果 治疗组的CRP复常时间、体温复常时间和内毒素转阴时间均明显短于对照组.两组患者均未观察到空洞闭合,但治疗组47例患者的结核病灶有吸收好转(有效率78.3％)；对照组33例患者的结核病灶有吸收好转(有效率55.0％),两组比较差异有统计学意义(x2=4.97,P＜0.05).成本-效果分析表明对照组疗效较差且治疗成本明显偏高(P=0.013).结论 一清胶囊与常规抗菌治疗之间具有协同作用,能明显缩短病程和住院时间,两者联用成本效果更好,具有重要的经济价值.