A Method to Relate the Affecting Parameters and Estimate Dilution in Coal Mines

This study provides an overview of the various issues influencing Out-of-Seam Dilution (OSD) in longwall mining method. The collected data has been statistically analyzed to examine the effect of the some factors causing OSD in front of the longwall mining face. Multiple parameter regression analysis was conducted on affecting parameters and the OSD. The SPSS (Statistics Package for Social Sciences) for Windows software package was used for the statistics analysis. Finally, a relationship between affecting parameters and the OSD is established by using the multiple parameter regression results. Results of this study have revealed that depth of seam, dip of seam, roof quality and variation in seam thickness are the most important influence factors for OSD. The proposed method may be utilized for the estimation of OSD for similar mines since, it was based on actual collected data from the coal mines

Emerging trends in non-communicable disease mortality in South Africa, 1997 - 2010

Objectives. National trends in age-standardised death rates (ASDRs) for non communicable diseases (NCDs) in South Africa (SA) were identified between 1997 and 2010.Methods. As part of the second National Burden of Disease Study, vital registration data were used after validity checks, proportional redistribution of missing age, sex and population group, demographic adjustments for registration incompleteness, and identification of misclassified AIDS deaths. Garbage codes were redistributed proportionally to specified codes by age, sex and population group. ASDRs were calculated using mid-year population estimates and the World Health Organization world standard.Results. Of 594 071 deaths in 2010, 38.9% were due to NCDs (42.6% females). ASDRs were 287/100 000 for cardiovascular diseases (CVDs), 114/100 000 for cancers (malignant neoplasms), 58/100 000 for chronic respiratory conditions and 52/100 000 for diabetes mellitus. An overall annual decrease of 0.4% was observed resulting from declines in stroke, ischaemic heart disease, oesophageal and lung cancer, asthma and chronic respiratory disease, while increases were observed for diabetes mellitus, renal disease, endocrine and nutritional disorders, and breast and prostate cancers. Stroke was the leading NCD cause of death, accounting for 17.5% of total NCD deaths. Compared with those for whites, NCD mortality rates for other population groups were higher at 1.3 for black Africans, 1.4 for Indians and 1.4 for coloureds, but varied by condition.Conclusions. NCDs contribute to premature mortality in SA, threatening socioeconomic development. While NCD mortality rates have decreased slightly, it is necessary to strengthen prevention and healthcare provision and monitor emerging trends in cause-specific mortality to inform these strategies if the target of 2% annual decline is to be achieved

End-to-end performance modeling of passive remote sensing systems

The ultimate goal of end-to-end system modeling is to simulate all known physical effects which determine the content of the data, before flying an instrument system. In remote sensing, one begins with a scene, viewed either statistically or dynamically, computes the radiance in each spectral band, renders the scene, transfers it through representative atmospheres to create the radiance field at an aperture, and integrates over sensor pixels. We have simulated a comprehensive sequence of realistic instrument hardware elements and the transfer of simulated data to an analysis system. This analysis package is the same as that intended for use of data collections from the real system. By comparing the analyzed image to the original scene, the net effect of nonideal system components can be understood. Iteration yields the optimum values of system parameters to achieve performance targets. We have used simulation to develop and test improved multispectral algorithms for (1) the robust retrieval of water surface temperature, water vapor column, and other quantities; (2) the preservation of radiometric accuracy during atmospheric correction and pixel registration on the ground; and (3) exploitation of on-board multispectral measurements to assess the atmosphere between ground and aperture

Merging Galaxies in the SDSS EDR

We present a new catalog of merging galaxies obtained through an automated systematic search routine. The 1479 new pairs of merging galaxies were found in approximately 462 sq deg of the Sloan Digital Sky Survey Early Data Release (SDSS EDR; Stoughton et al. 2002) photometric data, and the pair catalog is complete for galaxies in the magnitude range 16.0 <= g* <= 20. The selection algorithm, implementing a variation on the original Karachentsev (1972) criteria, proved to be very efficient and fast. Merging galaxies were selected such that the inter-galaxy separations were less than the sum of the component galaxies' radii. We discuss the characteristics of the sample in terms of completeness, pair separation, and the Holmberg effect. We also present an online atlas of images for the SDSS EDR pairs obtained using the corrected frames from the SDSS EDR database. The atlas images also include the relevant data for each pair member. This catalog will be useful for conducting studies of the general characteristics of merging galaxies, their environments, and their component galaxies. The redshifts for a subset of the interacting and merging galaxies and the distribution of angular sizes for these systems indicate the SDSS provides a much deeper sample than almost any other wide-area catalog to date.Comment: 58 pages, which includes 15 figures and 6 tables. Figures 2, 8, 9, 10, 11, 13, and 14 are provided as JPEG files. For online atlas, see http://home.fnal.gov/~sallam/MergePair/ . Accepted for publication in A

Prevalence of readily detected amyloid blood clots in 'unclotted' Type 2 Diabetes Mellitus and COVID-19 plasma: a preliminary report

CITATION: Pretorius, E., et al.2020. Prevalence of readily detected amyloid blood clots in unclotted Type 2 Diabetes Mellitus and COVID-19 plasma : a preliminary report. Cardiovasc Diabetol, 19:193, doi:10.1186/s12933-020-01165-7.The original publication is available at https://cardiab.biomedcentral.comBackground: Type 2 Diabetes Mellitus (T2DM) is a well-known comorbidity to COVID-19 and coagulopathies are a common accompaniment to both T2DM and COVID-19. In addition, patients with COVID-19 are known to develop micro-clots within the lungs. The rapid detection of COVID-19 uses genotypic testing for the presence of SARS-Cov-2 virus in nasopharyngeal swabs, but it can have a poor sensitivity. A rapid, host-based physiological test that indicated clotting severity and the extent of clotting pathologies in the individual who was infected or not would be highly desirable. Methods: Platelet poor plasma (PPP) was collected and frozen. On the day of analysis, PPP samples were thawed and analysed. We show here that microclots can be detected in the native plasma of twenty COVID-19, as well as ten T2DM patients, without the addition of any clotting agent, and in particular that such clots are amyloid in nature as judged by a standard fluorogenic stain. Results were compared to ten healthy age-matched individuals. Results: In COVID-19 plasma these microclots are significantly increased when compared to the levels in T2DM. Conclusions: This fluorogenic test may provide a rapid and convenient test with 100% sensitivity (P < 0.0001) and is consistent with the recognition that the early detection and prevention of such clotting can have an important role in therapy.https://cardiab.biomedcentral.com/articles/10.1186/s12933-020-01165-7Publisher's versio

Proteomics of fibrin amyloid microclots in long COVID/post-acute sequelae of COVID-19 (PASC) shows many entrapped pro-inflammatory molecules that may also contribute to a failed fibrinolytic system

BackgroundPost-acute sequelae of COVID-19 (PASC), also now known as long COVID, has become a major global health and economic burden. Previously, we provided evidence that there is a significant insoluble fibrin amyloid microclot load in the circulation of individuals with long COVID, and that these microclots entrap a substantial number of inflammatory molecules, including those that might prevent clot breakdown. Scientifically, the most challenging aspect of this debilitating condition is that traditional pathology tests such as a serum CRP (C-reactive protein) may not show any significant abnormal inflammatory markers, albeit these tests measure only the soluble inflammatory molecules. Elevated, or abnormal soluble biomarkers such as IL-6, D-Dimer or fibrinogen indicate an increased risk for thrombosis or a host immune response in COVID-19. The absence of biomarkers in standard pathology tests, result in a significant amount of confusion for patients and clinicians, as patients are extremely sick or even bed-ridden but with no regular identifiable reason for their disease. Biomarkers that are currently available cannot detect the molecules present in the microclots we identified and are therefore unable to confirm their presence or the mechanisms that drive their formation.MethodsHere we analysed the protein content of double-digested microclots of 99 long COVID patients and 29 healthy controls. The patients suffering from long COVID reported their symptoms through a questionnaire completed by themselves or their attending physician.ResultsOur long COVID cohort's symptoms were found to be in line with global findings, where the most prevalent symptoms were constant fatigue (74%,) cognitive impairment (71%) and depression and anxiety (30%). Our most noteworthy findings were a reduced level of plasma Kallikrein compared to our controls, an increased level of platelet factor 4 (PF4) von Willebrand factor (VWF), and a marginally increased level of α-2 antiplasmin (α-2-AP). We also found a significant presence of antibodies entrapped inside these microclots.ConclusionOur results confirm the presence of pro-inflammatory molecules that may also contribute to a failed fibrinolysis phenomenon, which could possibly explain why individuals with long COVID suffer from chronic fatigue, dyspnoea, or cognitive impairment. In addition, significant platelet hyperactivation was noted. Hyperactivation will result in the granular content of platelets being shed into the circulation, including PF4. Overall, our results provide further evidence of both a failed fibrinolytic system in long COVID/PASC and the entrapment of many proteins whose presence might otherwise go unrecorded. These findings might have significant implications for individuals with pre-existing comorbidities, including cardiovascular disease and type 2 diabetes

Erythrocyte, Platelet, Serum Ferritin, and P-Selectin Pathophysiology Implicated in Severe Hypercoagulation and Vascular Complications in COVID-19

CITATION: Venter, C. et al. 2020. Erythrocyte, Platelet, Serum Ferritin, and P-Selectin Pathophysiology Implicated in Severe Hypercoagulation and Vascular Complications in COVID-19. International Journal of Molecular Sciences, 21(21). doi:10.3390/ijms21218234The original publication is available at https://www.mdpi.com/journal/ijmsProgressive respiratory failure is seen as a major cause of death in severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)-induced infection. Relatively little is known about the associated morphologic and molecular changes in the circulation of these patients. In particular, platelet and erythrocyte pathology might result in severe vascular issues, and the manifestations may include thrombotic complications. These thrombotic pathologies may be both extrapulmonary and intrapulmonary and may be central to respiratory failure. Previously, we reported the presence of amyloid microclots in the circulation of patients with coronavirus disease 2019 (COVID-19). Here, we investigate the presence of related circulating biomarkers, including C-reactive protein (CRP), serum ferritin, and P-selectin. These biomarkers are well-known to interact with, and cause pathology to, platelets and erythrocytes. We also study the structure of platelets and erythrocytes using fluorescence microscopy (using the markers PAC-1 and CD62PE) and scanning electron microscopy. Thromboelastography and viscometry were also used to study coagulation parameters and plasma viscosity. We conclude that structural pathologies found in platelets and erythrocytes, together with spontaneously formed amyloid microclots, may be central to vascular changes observed during COVID-19 progression, including thrombotic microangiopathy, diffuse intravascular coagulation, and large-vessel thrombosis, as well as ground-glass opacities in the lungs. Consequently, this clinical snapshot of COVID-19 strongly suggests that it is also a true vascular disease and considering it as such should form an essential part of a clinical treatment regime.https://www.mdpi.com/1422-0067/21/21/8234Publishers versio

Estimating the changing burden of disease attributable to unsafe water and lack of sanitation and hygiene in South Africa for 2000, 2006 and 2012

Background. The incidence of diarrhoeal disease is closely linked to socioeconomic and environmental factors, household practices and access to health services. South African (SA) district health information and national survey data report wide variation in the incidence and prevalence of diarrhoeal episodes in children under 5 years of age. These differentials indicate potential for reducing the disease burden through improvements in provision of water and sanitation services and changes in hygiene behaviour. Objectives. To estimate the burden of disease attributed to unsafe water, sanitation and hygiene (WASH) by province, sex and age group for SA in 2000, 2006 and 2012. Methods. Comparative risk assessment methodology was used to estimate the disease burden attributable to an exposure by comparing the observed risk factor distribution with a theoretical lowest possible population distribution. The study adapts the original World Health Organization scenario-based approach for estimating diarrhoeal disease burden from unsafe WASH, by assigning different standards of household water and sanitation-specific geographical classification to capture SA living conditions in rural, urban and informal settlements. Results. SA experienced an improvement in water and sanitation supply in eight of the nine provinces between 2001 and 2011, with the exception of Northern Cape Province. In 2011, 41% of South Africans lived with poor water and sanitation conditions; however, wide provincial inequalities exist. In 2012, it was estimated that 84.1% of all deaths due to diarrhoeal disease were attributable to unsafe WASH; this equates to 13 757 deaths (95% uncertainty interval (UI) 13 015 - 14 300). Of these diarrhoeal disease deaths, 48.2% occurred in children under 5 years of age, accounting for 13.9% of all deaths in this age group (95% UI 13.1 - 14.4). Between 2000 and 2012, the proportion of deaths attributable to diarrhoea reduced from 3.6% to 2.6%. Gauteng and Western Cape provinces experienced much lower WASHattributable death rates than the more rural, poorer provinces. Conclusion. Unsafe WASH remains an important risk factor for disease in SA, especially in children. High priority needs to be given to the provision of safe and sustainable sanitation and water facilities and promoting safe hygiene behaviours. The COVID-19 pandemic has reinforced the critical importance of clean water for preventing and containing disease

Prevalence of symptoms, comorbidities, fibrin amyloid microclots and platelet pathology in individuals with Long COVID/Post-Acute Sequelae of COVID-19 (PASC)

BackgroundFibrin(ogen) amyloid microclots and platelet hyperactivation previously reported as a novel finding in South African patients with the coronavirus 2019 disease (COVID-19) and Long COVID/Post-Acute Sequelae of COVID-19 (PASC), might form a suitable set of foci for the clinical treatment of the symptoms of Long COVID/PASC. A Long COVID/PASC Registry was subsequently established as an online platform where patients can report Long COVID/PASC symptoms and previous comorbidities.MethodsIn this study, we report on the comorbidities and persistent symptoms, using data obtained from 845 South African Long COVID/PASC patients. By using a previously published scoring system for fibrin amyloid microclots and platelet pathology, we also analysed blood samples from 80 patients, and report the presence of significant fibrin amyloid microclots and platelet pathology in all cases.ResultsHypertension, high cholesterol levels (dyslipidaemia), cardiovascular disease and type 2 diabetes mellitus (T2DM) were found to be the most important comorbidities. The gender balance (70% female) and the most commonly reported Long COVID/PASC symptoms (fatigue, brain fog, loss of concentration and forgetfulness, shortness of breath, as well as joint and muscle pains) were comparable to those reported elsewhere. These findings confirmed that our sample was not atypical. Microclot and platelet pathologies were associated with Long COVID/PASC symptoms that persisted after the recovery from acute COVID-19.ConclusionsFibrin amyloid microclots that block capillaries and inhibit the transport of O2 to tissues, accompanied by platelet hyperactivation, provide a ready explanation for the symptoms of Long COVID/PASC. Removal and reversal of these underlying endotheliopathies provide an important treatment option that urgently warrants controlled clinical studies to determine efficacy in patients with a diversity of comorbidities impacting on SARS-CoV-2 infection and COVID-19 severity. We suggest that our platelet and clotting grading system provides a simple and cost-effective diagnostic method for early detection of Long COVID/PASC as a major determinant of effective treatment, including those focusing on reducing clot burden and platelet hyperactivation

Estimating the changing burden of disease attributable to childhood stunting, wasting and underweight in South Africa for 2000, 2006 and 2012

Background. National estimates of childhood undernutrition display uncertainty; however, it is known that stunting is the most prevalent deficiency. Child undernutrition is manifest in poor communities but is a modifiable risk factor. The intention of the study was to quantify trends in the indicators of child undernutrition to aid policymakers. Objectives. To estimate the burden of diseases attributable to stunting, wasting and underweight and their aggregate effects in South African (SA) children under the age of 5 years during 2000, 2006 and 2012. Methods. The study applied comparative risk assessment methodology. Data sources for estimates of prevalence and population distribution of exposure in children under 5 years were the National Food Consumption surveys and the SA National Health and Nutrition Examination Survey conducted close to the target year of burden. Childhood undernutrition was estimated for stunting, wasting and underweight and their combined ‘aggregate effect’ using the World Health Organization (WHO) 2006 standard. Population-attributable fractions for the disease outcomes of diarrhoea, lower respiratory tract infections, measles and protein-energy malnutrition were applied to SA burden of disease estimates of deaths, years of life lost, years lived with a disability and disability-adjusted life years for 2000, 2006 and 2012. Results. Among children aged under 5 years between 1999 and 2012, the distribution of anthropometric measurements <‒2 standard deviations from the WHO median showed little change for stunting (28.4% v. 26.6%), wasting (2.6% v. 2.8%) and underweight (7.6% v. 6.1%). In the same age group in 2012, attributable deaths due to wasting and aggregated burden accounted for 21.4% and 33.2% of the total deaths, respectively. Attributable death rates due to wasting and aggregate effects decreased from ~310 per 100 000 in 2006 to 185 per 100 000 in 2012. Conclusion. The study shows that reduction of childhood undernutrition would have a substantial impact on child mortality. We need to understand why we are not penetrating the factors related to nutrition of children that will lead to reducing levels of stunting