Post-heat treatment of electrochemically carburized low-carbon steel

Limited studies are available on post-heat treatment (tempering/annealing) of electro­chemically carburized low-carbon steel, which can relieve internal stresses induced by the quenching process. In this study, the electrochemical carburization was carried out using the electrolyte mixture of sodium carbonate (Na2CO3) and sodium chloride (NaCl) under a CO2 gas environment and 800 °C. The samples were then quenched in either water or oil. The peak hardness of the water-quenched sample (WQ) was higher than the oil-quenched sample (OQ). Comparatively, post-heat treated (tempered and annealed) samples showed lower peak hardness compared to quenched samples. An optical microscope was used to observe microstructural changes, while X-ray diffraction (XRD) was used to examine metal phases within all samples. The full width at half maximum (FWHM) of the martensite peak supported the stress relief in both tempered and annealed samples. Scanning electron microscope (SEM) with energy dispersive X-ray (EDX) was applied to determine the elemental composition of as received and electrochemically carburized and quenched low-carbon steel samples. The carbon content of the WQ sample was relatively higher than the OQ sample, whereas the tempered samples showed higher carbon content compared to the annealed samples, but both were lower than for quenched samples. Electrochemical carburization increased the carbon content and improved the hardness, while the tempering or annealing process relieved internal stresses that resulted in the hardness reduction

Borderline Hypertension

Borderline hypertension was the topic of one of the “Hypertension seminars” arranged by the Hypertension Section at the Östra Hospital, GÖteborg, Sweden. On that occasion Professor Stevo Julius, Ann Arbor, Michigan, USA, was an invited guest. During the seminar, various aspects of borderline hypertension were discussed, e.g. the natural history, hemodynamics and management of this condition. The present review is based on these discussions.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72079/1/j.0954-6820.1980.tb01235.x.pd

A review on the development of electro-carburisation process

The purpose of this paper is to review the early development of electro-carburisation technology and the research findings related to the electro-carburisation process. In general, conventional liquid carburisation of steel using a molten cyanide bath is carried out to improve the performance of mild steel, however this process produces toxic cyanide waste. Thus, other alternatives for liquid carburisation are necessary. Electro-carburisation process using carbonatebase molten salt, under a CO2 environment was developed as one of the alternatives to liquid carburising. Metal to be treated is exposed to the carbon-rich liquid in the molten cyanide bath and electro-carburisation. However, the metal is simply immersed inside the cyanide bath during conventional liquid carburising, while connected to the cathode in the electro-carburisation. The electro-carburisation involves a diffusion of carbon atoms into the surface of the metal which enhance the surface hardness of the metal. The effects of electrolysis parameters to the surface hardness and case hardening of treated metal have been reported in several journals. This article summarises the research findings. Apart from that, the quenching process and heat treatment post quenching also plays an important role in the quality of the carburised metal, therefore also reviewed in this article

Health-industry linkages for local health: reframing policies for African health system strengthening

The benefits of local production of pharmaceuticals in Africa for local access to medicines and to effective treatment remain contested. There is scepticism among health systems experts internationally that production of pharmaceuticals in sub-Saharan Africa (SSA) can provide competitive prices, quality and reliability of supply. Meanwhile low-income African populations continue to suffer poor access to a broad range of medicines, despite major international funding efforts. A current wave of pharmaceutical industry investment in SSA is associated with active African government promotion of pharmaceuticals as a key sector in industrialization strategies. We present evidence from interviews in 2013–15 and 2017 in East Africa that health system actors perceive these investments in local production as an opportunity to improve access to medicines and supplies. We then identify key policies that can ensure that local health systems benefit from the investments. We argue for a ‘local health’ policy perspective, framed by concepts of proximity and positionality, which works with local priorities and distinct policy time scales and identifies scope for incentive alignment to generate mutually beneficial health–industry linkages and strengthening of both sectors. We argue that this local health perspective represents a distinctive shift in policy framing: it is not necessarily in conflict with ‘global health’ frameworks but poses a challenge to some of its underlying assumptions

Potential impact of infant feeding recommendations on mortality and HIV-infection in children born to HIV-infected mothers in Africa: a simulation

<p>Abstract</p> <p>Background</p> <p>Although breast-feeding accounts for 15–20% of mother-to-child transmission (MTCT) of HIV, it is not prohibited in some developing countries because of the higher mortality associated with not breast-feeding. We assessed the potential impact, on HIV infection and infant mortality, of a recommendation for shorter durations of exclusive breast-feeding (EBF) and poor compliance to these recommendations.</p> <p>Methods</p> <p>We developed a deterministic mathematical model using primarily parameters from published studies conducted in Uganda or Kenya and took into account non-compliance resulting in mixed-feeding practices. Outcomes included the number of children HIV-infected and/or dead (cumulative mortality) at 2 years following each of 6 scenarios of infant-feeding recommendations in children born to HIV-infected women: Exclusive replacement-feeding (ERF) with 100% compliance, EBF for 6 months with 100% compliance, EBF for 4 months with 100% compliance, ERF with 70% compliance, EBF for 6 months with 85% compliance, EBF for 4 months with 85% compliance</p> <p>Results</p> <p>In the base model, reducing the duration of EBF from 6 to 4 months reduced HIV infection by 11.8% while increasing mortality by 0.4%. Mixed-feeding in 15% of the infants increased HIV infection and mortality respectively by 2.1% and 0.5% when EBF for 6 months was recommended; and by 1.7% and 0.3% when EBF for 4 months was recommended. In sensitivity analysis, recommending EBF resulted in the least cumulative mortality when the a) mortality in replacement-fed infants was greater than 50 per 1000 person-years, b) rate of infection in exclusively breast-fed infants was less than 2 per 1000 breast-fed infants per week, c) rate of progression from HIV to AIDS was less than 15 per 1000 infected infants per week, or d) mortality due to HIV/AIDS was less than 200 per 1000 infants with HIV/AIDS per year.</p> <p>Conclusion</p> <p>Recommending shorter durations of breast-feeding in infants born to HIV-infected women in these settings may substantially reduce infant HIV infection but not mortality. When EBF for shorter durations is recommended, lower mortality could be achieved by a simultaneous reduction in the rate of progression from HIV to AIDS and or HIV/AIDS mortality, achievable by the use of HAART in infants.</p

Deceased organ donation activity and efficiency in Switzerland between 2008 and 2017: achievements and future challenges.

Various actions have been taken during the last decade to increase the number of organs from deceased donors available for transplantation in Switzerland. This study provides an overview on key figures of the Swiss deceased organ donation and transplant activity between 2008 and 2017. In addition, it puts the evolution of the Swiss donation program's efficiency in relation to the situation in the neighboring countries. This study is an analysis of prospective registry data, covering the period from 1 January 2008 to 31 December 2017. It includes all actual deceased organ donors (ADD) in Switzerland. Donor data were extracted from the Swiss Organ Allocation System. The "donor conversion index" (DCI) methodology and data was used for the comparison of donation program efficiency in Switzerland, Germany, Austria, Italy and France. During the study period there were 1116 ADD in Switzerland. The number of ADD per year increased from 91 in 2008 to 145 in 2017 (+ 59%). The reintroduction of the donation after cardiocirculatory death (DCD) program in 2011 resulted in the growth of annual percentages of DCD donors, reaching a maximum of 27% in 2017. The total number of organs transplanted from ADD was 3763 (3.4 ± 1.5 transplants per donor on average). Of these, 48% were kidneys (n = 1814), 24% livers (n = 903), 12% lungs (n = 445), 9% hearts (n = 352) and 7% pancreata or pancreatic islets (n = 249). The donation program efficiency assessment showed an increase of the Swiss DCI from 1.6% in 2008 to 2.7% in 2017 (+ 69%). The most prominent efficiency growth was observed between 2012 and 2017. Even though Swiss donation efficiency increased during the study period, it remained below the DCI of the French and Austrian donation programs. Swiss donation activity and efficiency grew during the last decade. The increased donation efficiency suggests that measures implemented so far were effective. The lower efficiency of the Swiss donation program, compared to the French and Austrian programs, may likely be explained by the lower consent rate in Switzerland. This issue should be addressed in order to achieve the goal of more organs available for transplantation

The underlying mechanisms for development of hypertension in the metabolic syndrome

High blood pressure is an important constituent of the metabolic syndrome. However, the underlying mechanisms for development of hypertension in the metabolic syndrome are very complicated and remain still obscure. Visceral/central obesity, insulin resistance, sympathetic overactivity, oxidative stress, endothelial dysfunction, activated renin-angiotensin system, increased inflammatory mediators, and obstructive sleep apnea have been suggested to be possible factors to develop hypertension in the metabolic syndrome. Here, we will discuss how these factors influence on development of hypertension in the metabolic syndrome