IMPACT OF AGRICULTURAL PRACTICES ON BIODIVERSITY OF SOIL INVERTEBRATES, ASSESSMENT THROUGH DNA METABARCODING APPROACH

In spite of the increase of the organically farmed areas worldwide, it has been always doubted if the organic farming really enhances the soil biodiversity, as the main component in the agroecosystems. This doubt was a target of many studies, trying to reveal the true impact of the applied agricultural practices in the adopted farming strategies, targeting the soil invertebrates as bioindicators of the impact. Unfortunately, the doubt is still, due to the limitations in the sampling and taxonomy of the soil\u2019s invertebrates communities. In the last years, the molecular approaches represent promising methods to overcome these limitations. Thus, the DNA metabarcoding was applied targeting the COI gene in the DNA extracted from soil samples collected in different farming strategies (organic vs non organic), with a different cropping systems (stable meadow vs barley) and different levels in the field from the margin to center, this sampling was performed in three seasons (May, July and October). In addition, the soil properties (pH, texture, N%, C% and C/N ratio) were determined for the selected samples. The illumine MiSeq run was performed and the obtained reads were processed bioinformatically to get the OTU table (Operational Taxonomic Unite). This OTU table was used for the statistical and ecological analysis. Finally, the QBS, a soil quality index depends on the soil inhibiting microarthropods, was calculated by its classic method and estimated based on the obtained molecular data, to check the correlation between the resulted values. Results showed that the DNA metabarcoding approach represents a promising method for the assessment of soil biodiversity in the agroecosystem, but this approach is not able to detect the seasonal changes of the soil invertebrates\u2019 communities. Regarding the farming strategies, the farming management as organic or non organic (conventional) did not affect significantly the community structure of soil invertebrates and the biodiversity indices Shannon and Pielou\u2019s evenness, while the species richness was significantly lower in the conventional farm. Soil invertebrates\u2019 communities were significantly affected by the crop and the position of the field (as margin or field), and the C/N ratio. For Rotifera and Tardigrada communities\u2019 structure were affected by the farming strategy, while insects\u2019 communities were affected by the pH of the soil. The role of the margin of the field as a reservoir is increased in the cultivated fields (barley), while in the stable meadows the interactions between the margin and the center of the field are lower. Finally, the soil biological quality is decreased from the margin to the center of the field (of the same field), also decreased in the barley field comparing to the stable meadows. The obtained molecular index mQBS that is developed based on the QBS-ar is a promising approach for the soil biological quality estimation

The Profitability of Using Pegged Currencies in Carry Trade: A Case of Saudi Riyal

This paper examines the profitability of using pegged currencies in carry trade. Conducting this exercise on Saudi riyal against six floating currencies has proven to be very rewarding especially when enhanced with forecasting methods. Carry trade is a very popular currency speculation strategy among traders, where they borrow low-interest currencies and invest in high-interest currencies. It is a strategy that takes advantage of interest rate differentials between two currencies. Such strategy should not work under uncovered interest parity (UIP), since according to UIP high interest rate currencies should depreciate against low interest rate currencies by the interest rate differential itself. But studies have shown that UIP does not stand and carry traders are profiting from it. As a result of its failure, carry traders are making returns matching the returns of the S&P 500 and outperforming it in terms of the Sharpe ratio

Modèles D’estimation De L’émission Du Méthane Entérique Des Animaux D’élevage Au Maroc

Enteric CH4 emissions have been of great scientific interest as they represent a real energy loss for livestock and are also responsible for global warming. The objective of this study is to measure enteric methane emissions in farm animals, and then develop models for estimating quantities emitted based on the amount of dry matter ingested (MSI). Holstein cows (n = 38) received dietary rations of 50% forage and 50% feed concentrate, and a linear regression model was developed to predict CH4 production per animal (g). CH4 (animal / day) from the amount of dry matter ingested and the equation obtained was as follows: Y = 19.05X. Here, Y is the amount of CH4 (g CH4 / cow / day) and X is the amount of ingested dry matter (kg), with R² = 0.91, r = 0.97, and RMSPE = 5.53%. For small ruminants (n = 22), three dietary levels were used and methane production was measured. In addition, the equation obtained was: Y = 12.21 X with R² = 0.81, r = 0, 91 and RMSPE = 15.80%. In camelins (n = 12) and equines (n = 10), only one food level was used and methane measurements did not develop an estimation model. However, mean values of methane production were determined and they corresponded to 11.41 g CH4 / kg MSI in camels and 2.18 g CH4 / kg MSI in horses

SAFE HAVEN ASSETS: ARE THEY STILL SAFE DURING COVID-19 PANDEMIC PERIOD?

During political, financial, and economic turmoil periods investors tend to flee toward what is called safe haven assets such as gold, Swiss franc and lately, Bitcoin. While previous literature supports such assumption, these studies were based on crises that faced certain geographic locations. The coronavirus pandemic on the other hand is a global crisis that affects the whole world. This study aims to examine the validity of the assumption that the Swiss franc, gold, and Bitcoin would still act as safe haven assets during Covid-19 pandemic period. Results obtained from this study shows that Swiss franc, gold had a positive returns during the study period which is in line with safe haven assets characteristics, but these returns were not caused by the stock markets negative returns. Bitcoin on the other hand showed negative returns during the study period and statistically significant positive relation with S&P 500 returns indicating that Bitcoin cannot be used as a safe haven asset. JEL: G10; G11; G15  Article visualizations

MARKETING EXPENDITURE IMPACT ON BANK’S FINANCIAL PERFORMANCE: A CASE STUDY ON KUWAITI BANKS

Marketing personnel are always under pressure to justify their marketing strategies expenses to bank top management and shareholders. This study aims to provide some justification for their expenses by linking it to the financial performance of the firm. Using the data of ten Kuwaiti banks that are listed at Kuwait stock exchange (KSE) over the period spanning from 2008 to 2018, results show that there is a statistically significant direct relation between marketing expenditure and the financial performance of banks in Kuwait. In addition, results show that both bank size and assets per employee also have a direct relation with bank performance. JEL: G21; G24; G10 Article visualizations

Enabling Intelligent IoTs for Histopathology Image Analysis Using Convolutional Neural Networks

Medical imaging is an essential data source that has been leveraged worldwide in healthcare systems. In pathology, histopathology images are used for cancer diagnosis, whereas these images are very complex and their analyses by pathologists require large amounts of time and effort. On the other hand, although convolutional neural networks (CNNs) have produced near-human results in image processing tasks, their processing time is becoming longer and they need higher computational power. In this paper, we implement a quantized ResNet model on two histopathology image datasets to optimize the inference power consumption. We analyze classification accuracy, energy estimation, and hardware utilization metrics to evaluate our method. First, the original RGBcolored images are utilized for the training phase, and then compression methods such as channel reduction and sparsity are applied. Our results show an accuracy increase of 6% from RGB on 32-bit (baseline) to the optimized representation of sparsity on RGB with a lower bit-width, i.e., \u3c8:8\u3e. For energy estimation on the used CNN model, we found that the energy used in RGB color mode with 32-bit is considerably higher than the other lower bit-width and compressed color modes. Moreover, we show that lower bit-width implementations yield higher resource utilization and a lower memory bottleneck ratio. This work is suitable for inference on energy-limited devices, which are increasingly being used in the Internet of Things (IoT) systems that facilitate healthcare systems

Co-occurrence de mycotoxines dans les aliments pour volailles et les ingrédients alimentaires commercialisés au Maroc

This study investigated the contamination of poultry feed-ingredients and compound feed used in Morocco. ELISA analysis was performed on a total of 73 samples with corn (n = 59), soy (n = 8), and wheat (n=6). HPLC-MS/MS method was used for the quantification of Aflatoxin B1 (AFB1), Zearalenone (ZEA), Deoxynivalenol (DON), and fumonisin B1 (FUMB1) in corn (n = 10), soy (n = 5), wheat (n = 5), and compound feed (n = 18). Results of ELISA showed that the analyzed corn samples contained at least AFB1, DON, FUMB1 at the respective mean concentrations of 2.88, 3213, and 6241 ug/kg. For soya and wheat, the respective mean concentrations were 26 and 45 ug/kg of FUMB1, mean while DON was only detected in wheat samples at the mean concentration of 2,80 ug/kg. The HPLC-MS/MS showed that corn samples were contaminated by AFB1, DON, FUMB1, ZEA with average concentrations of 0.35, 2523, 6542, and 41.9 ug/kg, respectively. Soybean samples were contaminated with DON, FUMB1, and ZEA at the mean concentrations of 6.6, 73.9, and 75.7 ug/kg, respectively. Wheat were contaminated by, DON, FUMB1, and ZEA, at average concentrations of 1.99, 179, 4.01 ug/kg, respectively. AFB1, DON, FUMB1, and ZEA were detected in compound feed at average concentrations of 0.73, 3420, 4072 and 59, respectively. However, in all samples, mycotoxins concentrations did not exceed the maximum limits of the European Union standards and Ochratoxin is not detected. Key words: Aflatoxins, Zearalenone, Deoxynivalenol, OchratoxinA, Fumonisins, Corn, Soybean, Poultry compound feedL’objectif de notre étude est d’examiner la contamination des matières premières pour aliments de volailles et les aliments composés utilisés au Maroc. 73 échantillons ont été analysés par la méthode ELISA avec (n = 59) pour le maïs, le soja (n = 8) et le blé (n = 6). La méthode HPLC-MS / MS a été utilisée pour la quantification de l'aflatoxine B1 (AFB1), de la zéaralénone (ZEA), du désoxynivalénol (DON), de la fumonisine B1 (FUMB1) et de l’OchratoxinA (OTA), dans ces differentes Matrice le maïs (n = 10), le soja (n = 5), le blé (n = 5) et les aliments composés fabriqués avec ces matières premières (n = 18). Les résultats de l'ELISA ont montré que les échantillons de maïs analysés contenaient au moins AFB1, DON, FUMB1 aux concentrations moyennes respectives de 2,88, 3213 et 6241 ug / kg. Pour le soja et le blé, les concentrations moyennes respectives étaient de 26 et 45 ug / kg de FUMB1, alors que le DON n'a été détecté que dans des échantillons de blé à la concentration moyenne de 2,80 ug / kg. La méthode HPLC-MS / MS a montré que les échantillons de maïs étaient contaminés par AFB1, DON, FUMB1, ZEA avec des concentrations moyennes de 0,35, 2523, 6542 et 41,9 ug / kg, respectivement. Les échantillons de soja ont été contaminés par DON, FUMB1 et ZEA respectivement aux concentrations moyennes de 6,6, 73,9 et 75,7 ug / kg. Le blé a été contaminé respectivement par, DON, FUMB1 et ZEA, à des concentrations moyennes de 1,99, 179 et 4,01 ug / kg. AFB1, DON, FUMB1 et ZEA ont été détectés respectivement dans les aliments composés à des concentrations moyennes de 0,73, 3420, 4072 et 59. Cependant, dans tous les échantillons, les concentrations de mycotoxines n'ont pas dépassé les limites maximales des normes de l'Union européenne et l'ochratoxine n'est pas détectée dans l’ensemble des échantillons et par les deux méthodes. Mots clés: aflatoxines, zéaralénone, déoxynivalénol, ochratoxine, fumonisines, maïs, soja, aliments composés pour volaille

Effective transfer entropy approach to information flow between exchange rates and stock markets

We investigate the strength and direction of information flow between exchange rates and stock prices in several emerging countries by the novel concept of effective transfer entropy (an alternative non-linear causality measure) with symbolic encoding methodology. Analysis shows that before the 2008 crisis, only low level interaction exists between these two variables and exchange rates dominate stock prices in general. During crisis, strong bidirectional interaction arises. In the post-crisis period, the strong interaction continues to exist and in general stock prices dominate exchange rates. © 2014 Elsevier Ltd. All rights reserved

Cerebrovascular carbon dioxide reactivity and flow-mediated dilation in young healthy South Asian and Caucasian European men

Copyright © 2020 the American Physiological Society South Asians living in the United Kingdom have a 1.5-fold greater risk of ischemic stroke than the general population. Impaired cerebrovascular carbon dioxide (CO2) reactivity is an independent predictor of ischemic stroke and cardiovascular mortality. We sought to test the hypothesis that cerebrovascular CO2 reactivity is reduced in South Asians. Middle cerebral artery blood velocity (MCA Vm) was measured at rest and during stepwise changes in end-tidal partial pressure of CO2 (PETCO2) in South Asian (n = 16) and Caucasian European (n = 18) men who were young (~20 yr), healthy, and living in the United Kingdom. Incremental hypercapnia was delivered via the open-circuit steady-state method, with stages of 4 and 7% CO2 (~21% oxygen, nitrogen balanced). Cerebrovascular CO2 reactivity was calculated as the change in MCA Vm relative to the change in PETCO2. MCA Vm was not different in South Asians [59 (9) cm/s, mean (standard deviation)] and Caucasian Europeans [61 (12) cm/s; P > 0.05]. Similarly, cerebrovascular CO2 reactivity was not different between the groups [South Asian 2.53 (0.76) vs. Caucasian European 2.61 (0.81) cm·s-1·mmHg-1; P > 0.05]. Brachial artery flow-mediated dilation was lower in South Asians [5.48 (2.94)%] compared with Caucasian Europeans [7.41 (2.28)%; P 0.05). Flow-mediated dilation was not correlated with cerebrovascular CO2 reactivity measures. In summary, cerebrovascular CO2 reactivity and flow-mediated dilation corrected for shear rate are preserved in young healthy South Asian men living in the United Kingdom. NEW & NOTEWORTHY Previous reports have identified an increased risk of ischemic stroke and peripheral endothelial dysfunction in South Asians compared with Caucasian Europeans. The main finding of this study is that cerebrovascular carbon dioxide reactivity (an independent predictor of ischemic stroke) is not different in healthy young South Asian and Caucasian European men

Effet de l'huile de tournesol sur l'émission de méthane entérique chez la vache laitière

The objective of this study is to evaluate the effect of sunflower oil on enteric methane emissions in dairy cows.  Fermentation in the digestive tract of ruminants contributes about 18% of world production of this potent greenhouse gas. The study focused on measuring methane production before and after the addition of sunflower oil to the ration of five Holstein cows. The basal ration was composed of 4 kg of feed concentrate and 3 kg of alfalfa hay. After two weeks of adaptation to diet, methane production was measured. Then, 200 ml of sunflower oil was added to the same basal ration and a second methane measurement was made after two weeks of adaptation. To assess the influence of the circadian cycle on methane production, five measurements of methane emissions were conducted over a period of 24 hours on the same animals. The daily amount of methane produced by cows was estimated to average 185 liters/day. Methane production by cows has decreased from 7.5 l/h to 4.1 l/h during an interval of 24 hours between meals, which represents a decrease of 45.2 %, and then increased again after the second meal to reach 7.1 l/h; it was not affected by the circadian cycle but by feeding time. Methane was predominantly emitted by eructation (89 %) and the remainder is removed with the respiratory gas (11%). The effect of sunflower oil on methane emission was small but significant (p <5%) with a reduction by 8.1 %. The affordable cost of this additive makes it a promising component to reduce emissions of enteric methane in the atmosphere. Keywords: Greenhouse effect, Fermentation, Sunflower oil, Methane, Dairy Cattle.L’objectif de la présente étude est l’évaluation de l’effet de l’huile de tournesol sur l’émission de méthane entérique chez la vache laitière. La fermentation dans le tube digestif des ruminants contribue par environ 18% à la production mondiale de ce puissant gaz à effet de serre. L’étude a porté sur la mesure de la production de méthane avant et après l’ajout de l’huile de tournesol à la ration de cinq vaches Holstein. La ration de base est composée de 4 Kg d’aliment concentré et de 3 Kg de foin de luzerne. Après deux semaines d’adaptation au régime alimentaire, la production de méthane a été mesurée. Ensuite, 200 ml de l’huile de tournesol ont été ajoutés à la même ration de base et une deuxième mesure de méthane a été effectuée après deux semaines d’adaptation. Afin d’évaluer l’influence du cycle nycthéméral sur la méthanogénèse, cinq mesures d’émissions de méthane ont été effectuées durant une période de 24 h sur les mêmes animaux. La quantité journalière du méthane produit par les vaches a été estimée à environ 185 l/j. La production de méthane par les vaches a baissé de 7,5 l/h à 4,1 l/h durant un intervalle de 24 h entre les repas, ce qui représente une diminution de 45,2 %, puis a remonté après le deuxième repas pour atteindre 7,1 l/h, elle n’a pas été affectée par le cycle nycthéméral. Le méthane est en majorité émis en éructation (89 %) et le reste est éliminé avec les gaz respiratoires (11%). L’effet de l’huile de tournesol sur l’émission de méthane a été léger mais significatif (p <5%) avec une réduction de 8,1 %. Le coût abordable de cet additif fait de lui un moyen prometteur pour réduire les émissions du méthane entérique dans l’atmosphère. Mots clés: Effet de serre, Fermentation, Huile de tournesol, Méthane, Vache laitière.   &nbsp