Ion beam analysis techniques: a powerful set ge tools for identification and sourcing of ancient gems

Gemstones are defined as rare minerals having a high clarity, a high hardness and showing a bright colour and a nice shining. The most important gems are diamond, sapphire and emerald. These gems are callad precious stones. Gems have fascinated man since the earliest times. They have always been sought out by man for their aesthetic and symbolic valué. Due to their scarceness and high '^alue, gems were appreciated by the mighty ones as a sign of their power (emperors ^nd kings, dignitaries of religions ...). Their high hardness and henee strong resismnce to deterioration symbolised the everlastingness of their reign. This last property is interesting from an archaeological point of view: gemstones travel through time without noticeable alteration, even buried in aggressive environment. On the other hand, gems oiay be used several times on different jewels, possibly cut and polished again. Like spices and other precious and sought-after items, gems were brought back from long distance. Accordingly, they are good tracers for ancient trading routes and influence of civilisations. Each civilisation had its own favourite gemstones: lapis lazuli in Egypt; amber and emerald in the Román Empire; gamet in early Middle Ages westem civil isations; jade, ruby and sapphire in Far-East cultures. Moreover, the provenance of some ancient gems such as emeralds or gamets is still debated. For all these reasons, the study of gems kept in museum collections is a promising research fíeld

TERRESTRIAL LASER SCANNER DATA TO SUPPORT COASTAL EROSION ANALYSIS: THE CONERO CASE STUDY

In this work a detailed TLS survey was carried out in summer 2012, in the Conero Regional Park (Marche, province of Ancona), along the "spiaggia San Michele" and "spiaggia Sassi Neri". These areas present several sections affected by erosion, rock falls and slope failures. They also belong to a very prestigious place for tourism during the summer season; therefore, deriving a risk map for these areas is really useful. Thanks to the TLS survey, it was possible to obtain a centimetre resolution DTM covering a reach of about 1.5 km of the coast. This high resolution DTM was used to derive some primary topographic attributes that allowed to arrange a preliminary discussion about the likely unstable areas. These topographic information and results will also serve as the reference point for future yearly TLS surveys, which will absolutely help in recognizing any micro changes and slope failures, improving the risk maps

Pathogenesis of chronic obstructive pulmonary disease: An African perspective

The importance of chronic obstructive pulmonary disease (COPD) as a global health problem cannot be overstated. According to the latestWorld Health Organization statistics (2005), 210 million people suffer from COPD worldwide, and 5% of all deaths globally are estimated tobe caused by this disease. This corresponds to >3 million deaths annually, of which 90% are thought to occur in low- and middle-income countries.While cigarette smoking remains the major risk factor, and much of the increase in COPD is associated with projected increases in tobaccouse, epidemiological studies have demonstrated that in the majority of patients in developing countries the aetiology of COPD is multifactorial.This article summarises the epidemiology of and risk factors for COPD in Africa, including influences other than cigarette smoking thatare important contributors to chronic irreversible airflow limitation in our setting

Pathogenesis of chronic obstructive pulmonary disease : an African perspective

CITATION: Allwood, B. & Calligaro, G . 2015. Pathogenesis of chronic obstructive pulmonary disease : an African perspective. South African Medical Journal, 105(9):789, doi:10.7196/SAMJnew.8424.The original publication is available at http://www.samj.org.zaThe importance of chronic obstructive pulmonary disease (COPD) as a global health problem cannot be overstated. According to the latest World Health Organization statistics (2005), 210 million people suffer from COPD worldwide, and 5% of all deaths globally are estimated to be caused by this disease. This corresponds to >3 million deaths annually, of which 90% are thought to occur in low- and middle-income countries. While cigarette smoking remains the major risk factor, and much of the increase in COPD is associated with projected increases in tobacco use, epidemiological studies have demonstrated that in the majority of patients in developing countries the aetiology of COPD is multifactorial. This article summarises the epidemiology of and risk factors for COPD in Africa, including influences other than cigarette smoking that are important contributors to chronic irreversible airflow limitation in our setting.AFRIKAANSE OPSOMMING: Geen opsomming beskikbaarhttp://www.samj.org.za/index.php/samj/article/view/9973Publisher's versio

Tuberculosis burden in stage 5 chronic kidney disease patients undergoing dialysis therapy at Livingstone Hospital, Port Elizabeth, South Africa

Background. Tuberculosis (TB) is currently the leading cause of death from a single infectious agent worldwide. Patients who receive dialysis are particularly vulnerable to TB infection owing to immune dysfunction. Nonetheless, there is a paucity of incidence data on dialysis patients infected with TB in high-burden countries, such as South Africa (SA).Objectives. To determine the incidence of TB in prevalent chronic kidney disease stage 5 (CKD-5D) patients on dialysis at a single centre in Eastern Cape Province, SA, and to identify the risk factors associated with TB infection.Methods. We conducted a retrospective cohort study of all consenting CKD-5D patients between April 2010 and March 2014 at Livingstone Hospital Renal Unit, Port Elizabeth, the Eastern Cape. TB was defined as definite or probable according to World Health Organization (WHO) criteria, and the cohort was split into those who developed TB (TB+) and those who did not (TB−).Results. One hundred and eleven patients were enrolled – predominantly black Africans (73%) and women (53%); the mean age (standard deviation (SD)) was 42 (9.8) years. The prevalence of HIV infection was 11%, all patients were receiving antiretroviral treatment and all had suppressed viral loads. Sixty-eight patients were on haemodialysis and 43 on peritoneal dialysis. Nineteen patients were diagnosed with 20 episodes of TB; 14 cases were pulmonary TB and 6 cases extrapulmonary TB. Of the patients with TB, 2 were HIV-infected, 7 (35%) were definite TB cases and 13 (65%) were probable cases. The calculated incidence rate was 4 505/100 000 patient years. Only informal housing (30% in TB+ v. 12% in TB−; p=0.042) and a history of hospitalisation (90% v. 76%, respectively; p=0.042) were significantly associated with a diagnosis of TB.Conclusions. Dialysis patients in the Eastern Cape region of SA are at extremely high risk of acquiring TB, with an incidence rate 4.1 times that of the local population and >5 times that of the general SA population. Only informal housing and a history of hospitalisation were identified as positive risk factors for TB in this young population with a low HIV prevalence. Isoniazid prophylaxis in this high-risk group might be of benefit, but further studies are required to inform such treatment

High-Resolution monitoring of current rapid transformations on glacial and periglacial environments

Glacial and periglacial environments are highly sensitive to climatic changes. Processes of cryosphere degradation may strongly impact human activities and infrastructures, and need to be monitored for improved understanding and for mitigation/adaptation. Studying glacial and periglacial environments using traditional techniques may be difficult or not feasible, but new remote sensing techniques like terrestrial and aerial laser scanner opened new possibilities for cryospheric studies. This work presents an application of the terrestrial laser scanner (TLS) for monitoring the current rapid changes occurring on the Montasio Occidentale glacier (Eastern Italian alps), which is representative of low-altitude, avalanche-fed and debris-cover glaciers. These glaciers are quite common in the Alps but their reaction to climate changes is still poorly known. The mass balance, surface velocity fields, debris cover dynamics and effects of meteorological extremes were investigated by repeat high-resolution TLS scanning from September 2010 to October 2012. The results were encouraging and shed light on the peculiar response of this glacier to climatic changes, on its current dynamics and on the feedback played by the debris cover, which is critical for its preservation. The rapid transformations in act, combined with the unstable ice mass, large amount of loose debris and channeled runoff during intense rainfalls, constitute a potential area for the formation of large debris flows, as shown by field evidences and documented by the recent literature

Clinical alert: Patterns of oxygen saturation in prolonged recovery from COVID-19 pneumonia

During the second wave of the COVID-19 pandemic in South Africa, a recurrent pattern of prolonged recovery after acute COVID-19 pneumonia, characterised by low oxygen saturation levels for >2 weeks, was observed in an intermediate-care facility in Cape Town. A case study together with a series of 12 patients is presented to illustrate this phenomenon, and two types of ‘sats gap’ are described, which were used by physiotherapists and doctors to monitor daily progress. We attempt to explain this prolonged recovery in terms of the possible pathophysiology, and suggest a number of learning points to guide further research

Study of the Failure Mechanism of a High-Density Polyethylene Liner in a Type IV High-Pressure Storage Tank

The use of Type IV cylinders for gas storage is becoming more widespread in various sectors, especially in transportation, owing to the lightweight nature of this type of cylinder, which is composed of a polymeric liner that exerts a barrier effect and an outer composite material shell that primarily imparts mechanical strength. In this work, the failure analysis of an HDPE liner in a Type IV cylinder for high-pressure storage was carried out. The breakdown occurred during a cyclic pressure test at room temperature and manifested in the hemispherical head area, as cracks perpendicular to the liner pinch-off line. The failed sample was thoroughly investigated and its characteristics were compared with those of other liners at different stages of production of a Type IV cylinder (blow molding, curing of the composite material). An examination of the liner showed that no significant chemical and morphological changes occurred during the production cycle of a Type IV cylinder that could justify the liner rupture, and that the most likely cause of failure was a design-related fatigue phenomenon

Prolonged treatment of COVID-19 pneumonia with high-flow nasal oxygen: A story of oxygen and resilience

The COVID-19 pandemic has placed significant strain on the oxygen delivery infrastructure of health facilities in resource-constrained health systems. In this case report, we describe a patient with severe COVID-19 pneumonia who was managed with high-flow nasal oxygen for 40 days, with an eventual successful outcome. We discuss the oxygen delivery infrastructure needed to offer this intervention, as well as the psychosocial impact on those undergoing treatment