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Since the beginning of COVID-19, human beings have been threatened by various aspects. As of February 14, 2022, this global pandemic has caused about 412 million cases and 5.8 million deaths worldwide. Stock markets are one of the most agile economic indicators. In this context, this study investigates how daily growth in deaths, daily growth in cases, and governmental interventions affect stock market returns in 21 emerging economies from January 22 to December 31, 2020. Our results indicate that government response policies to Covid-19 positively impact stock returns. Besides, the daily growths in deaths and cases negatively affect stock market returns. The results also indicate that government response policies also have an indirect positive effect on stock market returns by weakening the negative impact of the daily growth in COVID-19 confirmed cases and deaths.

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Weather factors are effective to transmission of various diseases. Middle East Respiratory Syndrome (MERS), Severe Acute Respiratory Syndrome (SARS), and kinds of influenza can be given as example these diseases. The novel corona virus which is called COVID-19 is the most dangerous problem all around the world in these days. Early studies have revealed that COVID-19 cases are affected by environmental factors. Therefore, the purpose of this paper is to examine the relationship between the number of novel coronavirus cases and several weather parameters in 81 provinces of Turkey. Mean incubation period of COVID-19 is in question. Thus, this paper also aims to provide better understanding of the exact incubation period in Turkey by employing four different timeframe which are on the day (lag 0), 3 days ago (lag 3), 7 days ago (lag 7) and 14 days ago (lag 14). We have considered population density as a control variable. The dataset cover COVID-19 cases, population density, average temperature, humidity, pressure, dew point, wind speed, and sunshine duration for 81 provinces of Turkey. We find that population density has a positive correlation with COVID-19 cases. We also find that in lag 3, all parameters except for sunshine duration are negatively correlated with COVID-19 cases and significant. However, only 3 parameters, temperature, air pressure and dew point are negatively correlated with COVID-19 cases and significant for lag 0, lag 7 and lag 14. In addition, temperature, air pressure and dew point parameters are negative and significant in all timeframes.

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While the agricultural sector contributes the economic growth, it also induces GHGs and causes environmental degradation. The effect of agriculture activities on environmental degradation receives attention last several years in environmental Kuznets curve (EKC) literature. The aim of this paper is to investigate the effect of agriculture activities (AGRI), energy consumption (EC), foreign direct investment (FDI), and trade openness (TO) on CO2 in the context of EKC hypothesis for the Next Eleven countries in the period of 1991-2019. For this purpose, we employ common correlated effects mean group estimator (CCEMG) to obtain panel and country-specific results. In addition, Dumitrescu-Hurlin panel causality test is used to examine the pairwise causal relationship between variables. The results show that the EKC hypothesis, the inverted U-shape relationship between CO2 and GDP, is valid for Bangladesh, Mexico, Nigeria, Turkey, and the panel. FDI has significantly positive association with CO2 for South Korea and the panel. TO has significantly negative association with CO2 for Bangladesh, Indonesia, Mexico, and the panel but significantly positive relationship with CO2 in Philippines. Moreover, the focus variable AGRI has significantly negative association with CO2 for Bangladesh, Turkey, and the panel but significantly positive relationship with CO2 for Mexico.

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BACKGROUND: The aim of this study was to determine the factors affecting mortality rate among patients with an electrical burn. METHODS: A total of 115 patients admitted to the emergency department and hospitalized in the Burn Treatment Center or Intensive Care Unit (ICU) due to the electrical burn, were included in the study. RESULTS: A total of 115 patients (4 female and 111 male) with a mean age of 32.88±12.87 years were included in the study. The mean hospitalization period was 25.03±20.50 days, and the mean total body surface area burned (% TBSA) was 22.83±15.54%. Among those patients, 9 (8.5%) expired, and the remaining 106 were discharged after treatment. In a logistic regression analysis, TBSA >20% (p=0.02, OR: 11.7, CI: 1.38-99.16); ICU requirement (p=0.005, OR: 1.28, CI: 1.08-1.58); erythrocyte transfusion requirement (p=0.02, OR: 12.48, CI: 1.44-107.83); fresh frozen plasma (FFP) requirement (p=0.03, OR: 10.23, CI: 1.18-88.17); albumin requirement (p=0.02, OR: 12.60, CI: 1.44-109.85); admission serum albumin level <3.5 mg/dl (p=0.04, OR: 7.25, CI: 0.82-63.64); and admission hemoglobin level <12 mg/dl (p=0.01, OR: 8.29, CI: 1.57-43.61) were determined as risk factors for mortality in patients with electrical burns. CONCLUSION: In clinical practice, defining a mortality risk analyzer using these factors may be helpful in the management of patients with electrical burns. Additional, more comprehensive studies are required to define the risk factors for mortality and long-term morbidities in patients with electrical burns.

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BACKGROUND: The aim of the present study was to present characteristic features and risk factors of paint thinner burns in order to raise awareness and help prevent these injuries. METHODS: Records of patients admitted to the burn unit due to paint thinner burns were retrospectively reviewed, and patients with comprehensive data available were included in the study. Total of 48 patients (3 female and 45 male) with mean age of 27.79±11.49 years (range: 4-58 years) were included in the study. RESULTS: Mean total hospitalization period was 30.25±27.11 days (range: 3-110 days), and mean total burn surface area was 32.53±24.06% (range: 3.0-90.0%). In 31 cases (64.6%), intensive care unit admission was required. Among all 48 patients, 9 (18.8%) died in hospital and remaining 38 were discharged after treatment. Primary cause of death was septicemia (n=7) or respiratory failure (n=6). Inhalation injury was present in 12 of the patients, 6 of whom died (50%). Statistically significant differences were found between expired and discharged patients when compared for presence of inhalation injury (p=0.01) and septicemia (p=0.031). CONCLUSION: Ignition of paint thinner is an important cause of burn injuries that may result in very severe clinical picture. Patients require prompt and careful treatment. Clinicians should be aware that inhalation injury and sepsis are the 2 main factors affecting mortality rate in this group of patients. With increased awareness, preventive measures may be defined. Further studies are warranted to decrease mortality rate in this subgroup of burn patients.

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Burn injuries are associated with the negative effects on the musculoskeletal system and are important causes of severe disabilities. The aim of this study was to evaluate bone mineral density (BMD), bone turnover markers, and 25(OH) vitamin D levels in male patients with sustained at least 1 year postburns involving more than 30% of the TBSA in comparison to a control group and evaluate the relation between the characteristics of scar tissue and BMD and 25(OH) vitamin D levels. The study included 25 male patients who previously sustained burn injuries involving more than 30% of the TBSA and 20 healthy subjects as the control group. The burn scars were assessed using the Modified Vancouver Scar Scale Score (MVSSS). BMD at the lumbar spine and femoral neck were measured. The blood tests included calcium, phosphorus, bone-specific alkaline phosphatase, thyroid stimulating hormone, parathyroid hormone, 25(OH) vitamin D, osteocalcin, and ß-isomerized form C-terminal telopeptide of type I collagen. The femoral neck z score and bone mass density values, 25(OH) vitamin D3, and bone-specific ALP were significantly lower in injured compared with the control group. There was a negative correlation between MVSSS and vitamin D levels. Femoral bone loss should be taken into consideration in patients who sustain burn injuries and preventive treatment strategies must be adopted in the early treatment of burn injuries. Particularly in patients with high MVSSS should be evaluated for possible vitamin D deficiency during the long term.

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For imaging problems in which numerical solutions need to be computed for both the inverse and the underlying forward problems, discretization can be a major factor that determines the accuracy of imaging. In this work, we analyze the effect of discretization on the accuracy of fluorescence diffuse optical tomography. We model the forward problem by a pair of diffusion equations at the excitation and emission wavelengths and consider a finite element discretization method for the numerical solution of the forward problem. For the inverse problem, we use an optimization framework which allows incorporation of a priori information in the form of zeroth- and first-order Tikhonov regularization terms. Next, we convert the inverse problem into a variational problem and use Galerkin projection to discretize the inverse problem. Following the discretization, we analyze the error in reconstructed images due to the discretization of the forward and inverse problems and present two theorems which point out the factors that may lead to high error such as the mutual dependence of the forward and inverse problems, the number of sources and detectors, their configuration and their positions with respect to fluorophore concentration, and the formulation of the inverse problem. Finally, we demonstrate the results and implications of our error analysis by numerical experiments. In the second part of the paper, we apply our results to design novel adaptive discretization algorithms.

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In the first part of this work, we analyze the effect of discretization on the accuracy of fluorescence diffuse optical tomography (FDOT). Our error analysis provides two new error estimates which present a direct relationship between the error in the reconstructed fluorophore concentration and the discretization of the forward and inverse problems. In this paper, based on these error estimates, we develop two new adaptive mesh generation algorithms for the numerical solutions of the forward and inverse problems in FDOT, with the objective of error reduction in the reconstructed optical images due to discretization while keeping the size of the discretized forward and inverse problems within the allowable limits. We present three-dimensional numerical simulations to demonstrate the improvements in accuracy, resolution and detectability of small heterogeneities in reconstructed images provided by the use of the new adaptive mesh generation algorithms. Finally, we compare our algorithms both analytically and numerically with the existing conventional adaptive mesh generation algorithms.

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Diffuse optical tomography (DOT) poses a typical ill-posed inverse problem with a limited number of measurements and inherently low spatial resolution. In this paper, we propose a hierarchical Bayesian approach to improve spatial resolution and quantitative accuracy by using a priori information provided by a secondary high resolution anatomical imaging modality, such as magnetic resonance (MR) or x-ray. In such a dual imaging approach, while the correlation between optical and anatomical images may be high, it is not perfect. For example, a tumour may be present in the optical image, but may not be discernable in the anatomical image. The proposed hierarchical Bayesian approach allows incorporation of partial a priori knowledge about the noise and unknown optical image models, thereby capturing the function-anatomy correlation effectively. We present a computationally efficient iterative algorithm to simultaneously estimate the optical image and the unknown a priori model parameters. Extensive numerical simulations demonstrate that the proposed method avoids undesirable bias towards anatomical prior information and leads to significantly improved spatial resolution and quantitative accuracy.

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Diffuse optical tomography is a typical inverse problem plagued by ill-condition. To overcome this drawback, regularization or constraining techniques are incorporated in the inverse formulation. In this work, we investigate the enhancement in recovering functional parameters by using physiological and spatial a priori constraints. More accurate recovery of the two main functional parameters that are the blood volume and the relative saturation is demonstrated through simulations by using our method compared to actual techniques.

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