Comparative Epidemiology of Coronavirus Infections in humans and animals

Coronavirusesare a group of RNA viruses that cause diseases in mammals and birds. In humans and birds, they cause respiratory tract infections that can range from mild to lethal. Mild illnesses in humans include some cases of the common cold, which can also be caused by other viruses, predominantly rhinoviruses, while more lethal varieties cause Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), or the current pandemic Coronavirus disease 2019 (COVID-19). In cows and pigs Coronaviruses cause diarrhea like the transmissible gastroenteritis virus (TGEV), while in young calves, the Bovine Coronavirus (BCV) causes severe profuse enteritis. In this review we will go over the microbiology of coronaviruses, their classifications and the different infections caused by it in animals and human

Regular tax revenues and their role in balancing Algeria’s budget Analysis study from 2000 to 2016

ترتكز معظم الموازنات العامة على ما أقرته السياسة المالية من الموارد العامة لتمويل النفقات العامة، ويهدف هذا المقال إلى تسليط الضوء على عنصر هام من عناصر الميزانية العامة في الجزائر وهو الإيرادات الجبائية العادية ومدى مساهمتها في تمويل النفقات العامة وتوازن الموازنة العامة في الجزائر  خلال فترة مهمة في الإقتصاد الجزائري، بعد تغير المناخ السياسي والأمني وتحسن الإقتصاد الجزائر وهي 2000-2016، وهذا من أجل معرفة الدور المهم الذي قد تلعبه الجباية العادية في مرحلة ما بعد الجباية البترولية في تمويل الموازنة العامة في ظل إنخفاض أسعار المحروقات. لقد توصلنا من خلال بحثنا إلى الأهمية الكبيرة لهذا النوع من الإيرادات وضرورة إعطائه الأولوية من أجل الإبتعاد والإستغناء عن التبعية للجباية البترولية في تمويل الميزانية العامة في الجزائر.Most of the public budgets are based on the public resources of the fiscal policy to finance public expenditures, and this article aims to highlight an important element of Algeria’s public budget: regular tax revenues and the extent to which they contribute to the financing of public expenditures and budget ary balance.The general public in Algeria during an important period in the Algerian economy after the change in the political and security climate and the improvement of the Algerian economy, which is 2000-2016, and this in order to know the important role that the regular levies in the post-levy oil phase may play in financing the general budget in light of the low prices Fuel.             Through our research, we have found the great importance of this type of revenue and the need to give priority to it in order to move away from dependence on oil revenues in the financing of Algeria’s public budget

COMBINED EFFECTS OF ELECTROSTATIC AND ELECTROMAGNETIC INTERFERENCES OF HIGH VOLTAGE OVERHEAD POWER LINES ON AERIAL METALLIC PIPELINE

The main purpose of this paper is to model and analyze the electrostatic and electromagnetic interferences between a HV overhead power line and an aerial metallic pipeline situated parallel at a close distance. The modelling of these interferences is typically done for safety reasons, to ensure that the induced voltage does not pose any risk to the operating and maintenance personnel and to the integrity of the pipeline. The adopted methodologies respectively for electrostatic and electromagnetic interferences are based on the charge and current simulation methods combined with the Teaching learning based optimization (TLBO) algorithm. The Friedman test  analysis indicate that teaching learning based optimization (TLBO) algorithm can be used for parameters optimization, it showed better results. In the case where the induced currents and voltages values exceed the limit authorized values by the international CIGRE standard, mitigation measures become necessary. The simulation results obtained were compared with those provided respectively by the admittance matrix analysis and Carson's method, good agreement was obtained

The supply response of rainfed agricultural crops to price changes in South Darfur State, Sudan

The objective of this study is to examine the supply response of rainfed agricultural crops to price changes in South Darfur State. The study was based on data collected for the period 1987- 2004. The data included area, production, rainfall, and relative prices. The analysis of data was based on the Nerlovian partial adjustment model. The results revealed that the supply response of individual crops was positive but generally low in the short-run and fairly high in the long-run. These results could be a useful tool for policies intended to enhance the production efficiency of rainfed agriculture in the State. The study also demonstrated the importance of having adequate and timely adoption of agricultural technology to promote the low response of individual crops and to maintain a sustainable food security for the State

Calculation of Critical Load for Pure Distortional Buckling of Lipped Channel Columns

This paper presents a method that allows calculating the elastic critical stress for the distortional buckling mode, based on the buckling mode classification of typical lipped channel columns. In our case, Cold-Formed Steel Lipped Channel Columns are subjected to compression. Moreover, in order to consolidate the important findings of this work, a comparative study was carried out to assess the reliability of various distortional buckling models that are provided by different design Standards. It was found that the American and Australian approaches, given in the codes of practice, are closer to the Finite Strip Method than to the European method. An analytical solution was proposed for the determination of the distortional buckling stress on the basis of a statistical method; it corresponds to lipped channel sections with a flange width to web width ratio b/h ranging from 0.1 to 1, and a lip width to web width ratio c/h between 0 and 0.5. After comparison with the results given by the finite strip method for pure distortional buckling, it turned out that the proposed approach provides a reasonable prediction for the elastic distortional buckling stress for lipped channel sections subjected to compression. In fact, this method gives better results than the American approach

Utilization of Waste Grooved Razor Shell (GRS) as a Catalyst in Biodiesel Production from Refined and Waste Cooking Oils

Biodiesel is a potential alternative for fossil fuel. However, its large-scale application is held up by the disadvantage of a homogenous process, the scarce availability of raw materials and the production cost, which is higher than for fossil diesel. In this work, biodiesel production was carried out using both refined and used cooking oils. The process was investigated in a batch reactor, in the presence of CaO as a heterogeneous catalyst prepared by the calcination of the natural Waste Grooved Razor Shell (GRS). Characterizations by X-Ray Diffraction (XRD) and Thermal Gravimetric (TG)/Differential Thermal Analysis (DTA) showed that the as-received GRS consists of aragonite, (i.e., CaCO3) as the main component and of water and organic matter in a lower amount. After calcination at 900 °C, CaO was formed as the only crystalline phase. The effects of several experimental parameters in the transesterification reactions were studied, and their impact on the produced biodiesel properties was investigated. The studied variables were the methanol/oil molar ratio, the catalyst weight percentage (with respect to the oil mass), the calcination temperature of the parent GRS and the recycling and regeneration of the catalyst. The physico-chemical and fuel properties, i.e., viscosity, density and acid value of used oils and of the produced biodiesel, were determined by conventional methods (American Society for Testing and Materials (ASTM) methods) and compared with the European standards of biodiesel. The optimal identified conditions were the following: the use of a 15:1 methanol/oil molar ratio and 5 wt% of CaO with respect to the oil mass. After 3 h of reaction at 65 °C, the biodiesel yield was equal to 94% and 99% starting from waste and refined oils, respectively

Anal Cancer with Atypical Brain and Cranial Bones Metastasis: About 2 Cases and Literature Review

Canal anal cancer is a rare tumor that accounts for 2% of all colorectal neoplasms, with a low propensity for metastasis. The spread of anal squamous cell carcinoma to the brain is exceedingly rare and has been previously reported only 5 times in the medical literature. However, the first and only case of cranial bone metastasis from anal canal carcinoma was described in 2019. The purpose of this article is to add our cases to the limited literature for the management of metastatic anal cancer. The current study presents 2 cases of patients diagnosed with squamous cell carcinoma of the anal canal how underwent chemo and radiotherapy. Despite the treatment our patients developed neurological symptoms, cerebral magnetic resonance imaging showed brain lesions for the first case, and cranial bones metastasis for the second one, histopathology confirmed these lesions to be a poorly differentiated squamous cell carcinoma, consistent with the known primary tumor of the anal canal. Unfortunately, both patients succumbed quickly to systemic complications of the disease during these treatments. Despite its rarity, brain metastasis should be considered in any patient with a history of anal cancer presented neurological symptoms

Author Correction: High-resolution cryo-EM structure of urease from the pathogen Yersinia enterocolitica

A Correction to this paper has been published: https://doi.org/10.1038/s41467-020-19845-z

Cohesive Properties of the Caulobacter crescentus Holdfast Adhesin Are Regulated by a Novel c-di-GMP Effector Protein

When encountering surfaces, many bacteria produce adhesins to facilitate their initial attachment and to irreversibly glue themselves to the solid substrate. A central molecule regulating the processes of this motile-sessile transition is the second messenger c-di-GMP, which stimulates the production of a variety of exopolysaccharide adhesins in different bacterial model organisms. In Caulobacter crescentus, c-di-GMP regulates the synthesis of the polar holdfast adhesin during the cell cycle, yet the molecular and cellular details of this control are currently unknown. Here we identify HfsK, a member of a versatile N-acetyltransferase family, as a novel c-di-GMP effector involved in holdfast biogenesis. Cells lacking HfsK form highly malleable holdfast structures with reduced adhesive strength that cannot support surface colonization. We present indirect evidence that HfsK modifies the polysaccharide component of holdfast to buttress its cohesive properties. HfsK is a soluble protein but associates with the cell membrane during most of the cell cycle. Coincident with peak c-di-GMP levels during the C. crescentus cell cycle, HfsK relocalizes to the cytosol in a c-di-GMP-dependent manner. Our results indicate that this c-di-GMP-mediated dynamic positioning controls HfsK activity, leading to its inactivation at high c-di-GMP levels. A short C-terminal extension is essential for the membrane association, c-di-GMP binding, and activity of HfsK. We propose a model in which c-di-GMP binding leads to the dispersal and inactivation of HfsK as part of holdfast biogenesis progression.IMPORTANCE Exopolysaccharide (EPS) adhesins are important determinants of bacterial surface colonization and biofilm formation. Biofilms are a major cause of chronic infections and are responsible for biofouling on water-exposed surfaces. To tackle these problems, it is essential to dissect the processes leading to surface colonization at the molecular and cellular levels. Here we describe a novel c-di-GMP effector, HfsK, that contributes to the cohesive properties and stability of the holdfast adhesin in C. crescentus We demonstrate for the first time that c-di-GMP, in addition to its role in the regulation of the rate of EPS production, also modulates the physicochemical properties of bacterial adhesins. By demonstrating how c-di-GMP coordinates the activity and subcellular localization of HfsK, we provide a novel understanding of the cellular processes involved in adhesin biogenesis control. Homologs of HfsK are found in representatives of different bacterial phyla, suggesting that they play important roles in various EPS synthesis systems

Exchange rate volatility and financial performance of agriculture firms in Malaysia: an empirical analysis using GARCH, wavelet and system GMM

The insurgence of exchange rate volatility over the years has gained the attention of not only scholars but also policy makers around the world. This paper investigates the influence of exchange rate volatility to the financial performance of agriculture firms in Malaysia. Authors use the system GMM dynamic panel techniques, wavelet coherence technique and GARCH (1, 1) for the period of 2001 and 2015. The findings show that the volatility of exchange rate of Malaysian Ringgit (RM) has a negative impact on the financial performance of agriculture firms in Malaysia. The ARME and AVA demonstrate a positive impact on the financial performance at 1% significance level for the full sample. The findings also reveal that financial performance, exchange rate, consumer price index, and interest rate comove while using the wavelet coherence