The Effect of Argon Inert Gas on the Laser Welding Quality of Co-Cr and Ni-Cr Base Metal Alloys

The purpose of this research was to study the effect of Argon inert gas on the laser welding quality of Co-Cr and Ni-Cr base metal alloys, which are widely used as Fixed Prosthodontics alloys in Dental Laboratories. A total of 36 specimens were manufactured (18 of Ni-Cr alloy and 18 of Co-Cr alloy). The specimens were then divided into 3 subgroups (6 specimens each): control;argon-welded;and non-Argon welded. The specimens were cut, laser welded, radiographed and finally tested under tensile strength testing, followed by examination using Scanning Electron Microscopy. The tensile strength of welded specimens was lower than the strength of non-welded specimens, however this difference was not found to be statistically significant. The material factor (Co-Cr alloy or Ni-Cr alloy) has a statistically significant effect on the tensile strength, while the presence or not of the inert gas, as well as the combination of the two factors do not have a statistically significant effect. The laser welding process applied in daily practice (separation of specimen, formation of two cones in contact, aggregation of two cones, filling of the remaining gap by welding) is considered satisfactory in terms of weld strength. The factor of the material, as an independent factor, affects the tensile strength to a statistically significant degree, in contrast to the factor of the presence of inert gas which does not affect to a statistically significant degree.

Emerging pharmacological strategies for the treatment of fibromyalgia

Fibromyalgia(FM) has been described as a chronic clinical condition related to multisensory hypersensitivitypresenting with a complex of symptoms dominated by chronic widespread pain associated with the existence of a range of co-morbidities, such as fatigue, sleep disturbance, cognitive impairment, anxiety and depression. Current treatments include drugs that target serotonin and noradrenaline levels within the central nervous system, e.g., tricyclic antidepressants, serotonin noradrenaline reuptake inhibitors, and voltage-gated calcium channel subunit ligands, e.g., gabapentin and pregabalin. Investigation of a range of novel targets, such as melatoninergic, cannabinoid, dopamine, NMDA, angiotensin, orexin and opioid receptors, and ion channels, in addition revisiting bioamine modulation and subunits has provided efficacy outcomes that improve the health status of patients with FM. Nevertheless, modest and limited efficacy is often observed reflecting the heterogeneity of FM with existence of subpopulations of patients, the contribution of peripheral and central components to the pathophysiology, and the extensive range of accompanying co-morbidities. The complexity and multidimensional nature of FM is emphasized by the diversity of pharmacological targets gaining interest. Clues to underlying mechanisms which offer themselves as novel and potential targets for new medications are being provided by advances in the understanding of the pathophysiology of FM.

COP27 climate change conference:urgent action needed for Africa and the world

Wealthy nations must step up support for Africa and vulnerable countries in addressing past,present and future impacts of climate changeThe 2022 report of the Intergovernmental Panel on Climate Change paints a dark picture of the future of life on earth,characterised by ecosystem collapse,species extinction and climate hazards such as heatwaves and floods.1 These are all linked to physical and mental health problems,with direct and indirect consequences of increased morbidity and mortality.To avoid these catastrophic health effects across all regions of the globe,there is broad agreement—as 231 health journals argued together in 2021—that the rise in global temperature must be limited to<1.5°C compared with pre-industrial levels.

Estimation of Fatigue Strength of Reinforced Complete Upper Denture Using a Newly Designed Testing Machine: A Laboratory Research Project

In the present study, an aero pneumatic fatigue testing machine for complete dentures was designed, fabricated, and tested for the evaluation of the fatigue life of reinforced complete upper denture (CUD). On completion and testing, it was observed that the machine has the potential of generating reliable number of cyclic data. The machine’s performance was evaluated using test specimens of identical CUDs that were machined in conformity with standard procedures. The fatigue machine compressed the lower dental arch over the upper denture-specimen in centric occlusion, in the same way that the two masticatory muscles pull the lower jaw over the upper jaw during chewing. The incorporation of glass fibres into the CUD using a sandwich technique quadruples the lifespan of the denture (P = 0.004). The low standard deviation, along with the low coefficient of variation (CV) of the group of unreinforced dentures shows the repeatability of the results and the reliability of the machine. The high standard deviation and coefficient of variation of reinforced dentures was expected, since a high variation of results is usually recorded in fibre reinforcement cases. This research confirmed the view that the crack during denture fracture initiates in the anterior palatal area and propagates to the posterior.

COP27 climate change conference: urgent action needed for Africa and the world

Wealthy nations must step up support for Africa and vulnerable countries in ad-dressing past,present and future impacts of climate change The 2022 report of the Intergovernmental Panel on Climate Change paints a dark picture of the future of life on earth,charac-terised by ecosystem collapse,species extinc-tion and climate hazards such as heatwaves and floods.1 These are all linked to physical and mental health problems,with direct and indirect consequences of increased morbidity and mortality.To avoid these catastrophic health effects across all regions of the globe,there is broad agreement-as 231 health jour-nals argued together in 2021-that the rise in global temperature must be limited to<1.5°C compared with pre-industrial levels.

Engaging black sub-Saharan African communities and their gatekeepers in HIV prevention programs: Challenges and strategies from England

Objective:HIV infection is a sensitive issue in black communities[Serrant-Green L.Black Caribbean men,sexual health decisions and silences.Doctoral thesis.Nottingham School of Nurs-ing,University of Nottingham;2004].Statistics show black sub-Saharan African(BSSA)com-munities disproportionately constitute two-thirds of people with HIV[Heath Protection Agency.Health protection report:latest infection reports-GOV.UK;2013].African communities constitute 30%of people accessing HIV treatment in the United Kingdom yet represent less than 1%of the population[Health Protection Agency.HIV in the United Kingdom:2012 report;2012],[Depart-ment of Health.DVD about FGM.2012.Available from fgm@dh.gsi.gov.uk.].This article ex-plores the sociocultural challenges in engaging BSSA communities in HIV prevention programs in England and possible strategies to improve their involvement.Methods:Twelve focus group discussions and 24 semistructured interviews were conducted in a 2-year period with participants from the BSSA communities and sexual health services in the West Midlands,England.The research was supported by the Ubuntu scheme,a sexual health initia-tive working with African communities in Birmingham,England.Results:Ineffective engagement with African communities can hinder the effectiveness of HIV prevention programs.Skills and strategies sensitive to BSSA culture are important for success-ful implementation of prevention programs.HIV prevention programs face challenges including stigma,denial,and marginalized views within BSSA communities.Conclusion:Networking,coordination,and cultural sensitivity training for health profession-als are key strategies for engaging BSSA communities in HIV prevention programs.

No benefit of flat head positioning in early moderate-severe acute ischaemic stroke: a HeadPoST study subgroup analysis

background Although the Head Positioning in acute Stroke Trial(HeadPoST)showed no effect of the flat head position(FP;vs sitting up head position(SUP))on functional outcome,we hypothesised that it could still offer benefits if commenced early in those with acute ischaemic stroke(AIS)of at least moderate severity.Methods Subgroup analysis of HeadPoST in participants with National Institutes of Health Stroke Scale(NIHSS)scores≥7,≥10 and≥14,randomised to FP or SUP<4.5 hours of AIS onset on functional outcomes defined by a shift in scores on the modified Rankin scale(mRS)and death/disability(mRS scores 3-6),and any cardiovascular serious adverse event.Logistic regression analyses were undertaken adjusted for study design and baseline risk factors.results There was no significant differential treatment effect in patient subgroups defined by increasing baseline NIHSS scores:adjusted OR and 95%CI for ordinal shift and binary(3-6)mRS scores:for NIHSS≥7(n=867)0.92(0.67 to 1.25)and 0.74(0.52 to 1.04);NIHSS≥10(n=606)0.80(0.58 to 1.10)and 0.77(0.49 to 1.19);NIHSS≥14(n=378)0.82(0.54 to 1.24)and 1.22(0.69 to 2.14).Conclusions Early FP had no significant effect in patients with moderate-severe AIS.