Measuring the effect of foreign exchange reserves on foreign direct investment in Algeria during the period 1990-2020 using the ARDL model

This paper aims to examine the impact of foreign exchange reserves on foreign direct investment in Algeria during the period 1990-2020 by applying the Auto-Regressive Distributed Lag model (ARDL). The model showed that the current variables are co-integrated. Also, the results indicate that foreign exchange reserves have a positive impact on foreign direct investment in the long term only, at a rate of 44%

Gemcitabine and treatment of diffuse large B-cell lymphoma in relapsed or refractory elderly patients: A prospective randomized trial in Algeria

Context: Support for non-Hodgkin\u2032s lymphoma (NHL) with large cells that is refractory or relapsed after first-line chemotherapy poses a greater therapeutic problem with bone marrow transplant therapy or when old age is a contra-indication for high-dose chemotherapy, especially among developing countries such as Algeria. Aim: To show that the regimen, including gemcitabine, could be more effective in treating elderly patients with diffuse large B-cell lymphoma (DLBCL) in relapse / refractory, without complete remission, when compared with the ESHAP (etoposide, cisplatine, solumedrol, aracytine) regimen. Materials and Methods: Ninety-six patients in the age group of 60-70 years were volunteers for a prospective randomized single-blind study, carried out for three years. Patients were divided into two groups by the drawing of lots. The first group (GA, n = 48, relapse; n = 27 [56.3%], refractory; n = 21 [43.7%]) received treatment with ESHAP protocol and the second one (GB, n = 48, relapse; n = 28 [58%], refractory; n = 20 [42%]) with GPD (gemcitabine, dexamethasone, cisplatine) protocol. Results: The overall response rates and mean survival at three years were significantly higher among patients subjected to GPD treatment compared with those subjected to ESHAP treatment (63% vs. 55%, P = 0.01 and 20.5% [95% CI 16.5-24.5] vs. 11.8% [8.9-14.6], respectively). Additionally, three-year progression-free and event-free survival rates were 20.5% (16.3-24) and 19.7% (15.9-23.5), respectively, for the GPD regimen and 10.9% (8.2-13.7) and 11.1% (95% CI 8.5-13.7), respectively, for the ESHAP regimen. Moreover, the GPD regimen was associated with improving overall survival (RR=2.02, 95% CI 1.59-2.56; P = 0.000), event-free survival (2.03, 1.64-2.52; P < 0.001) and progression-free survival (1.86, 1.46-2.37; P < 0.001). Conclusion: In cases of contra-indication for high-dose chemotherapy for elderly patients with DLBCL, without complete remission, the Gemcitabine-based therapy protocol represents a more effective and less toxic than that of ESHAP

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Simple intra-cavity beam shaping for generating a shape-invariant flat-top laser beam

International audienceFor laser users, the usual Gaussian beam (GB) may not always be the best intensity profile. Often, a preferred option is a Flat-Top (FT) beam which is generally obtained by using diffractive optics in a reshaping operation. In this case, the resulting FT profile occurs only in the focal plane of the focusing lens, and its vicinity. We consider here the generation of a shape-invariant FT laser beam resulting from the incoherent weighted (50%-50% in power) mixing of LG00 (GB) and LG01 (doughnut) beams. For that we consider the insertion inside the laser cavity of a diaphragm and an absorbing ring, and optimising their sizes makes possible the simultaneous oscillation on LG00 and LG01 modes allowing the generation of a shape-invariant laser beam

Numerical Study of Large-Scale Fire in Makkah’s King Abdulaziz Road Tunnel

Tunnel fires are one of the most dangerous catastrophic events that endanger human life. They cause damage to infrastructure because of the limited space in the tunnel, lack of escape facilities, and difficulty that intervention forces have in reaching the fire position, especially in highly crowded areas, such as Makkah in the Hajj season. Unfortunately, performing experimental tests on tunnel fire safety is particularly challenging because of the prohibitive cost, limited possibilities, and losses that these tests can cause. Therefore, large-scale modeling, using fire dynamic simulation, is one of the best techniques used to limit these costs and losses. In the present work, a fire scenario in the Makkah’s King Abdulaziz Road tunnel was analyzed using the Fire Dynamics Simulator (FDS). The effects of the heat released per unit area, soot yield, and CO yield on the gas temperature, radiation, concentrations of the oxygen and combustion products CO and CO2, and air velocity were examined. The results showed that the radiation increased with the heat released per unit area and the soot yield affected all parameters, except the oxygen concentration and air velocity. The CO yield significantly affects CO concentration, and its influence on the other studied parameters is negligible. Moreover, based on the validation part, the results proved that FDS have limitations in tunnel fires, which impact the smoke layer calculation at the upstream zone of the fire. Therefore, the users or researchers should carefully be concerned about these weaknesses when using FDS to simulate tunnel fires. Further comprehensive research is crucial, as tunnel fires have severe impacts on various aspects of people’s lives

Carbon and nitrogen balances and CO2 emission after exogenous organic matter application in arid soil

Addition of organic amendments (OAs) could be a means to sequester carbon (C) in soils. However, the efficiency of C sequestration depends on how OAs evolve in the soil. A field study was installed in arid soil to which was added one of five OAs – olive husk-based compost (CM), palm leaf-based compost (CP), crushed olive pruning (GW), fresh olive mill wastewater (OMW) or fermented ovine manure (OM) – at an equivalent fixed level of 350 g of C/m2. C and N mineralization were followed for 112 days by measuring the evolution of released CO2 and mineral N evolution. The results showed that CM and CP did not disturb soil respiration, with a very low CO2 emission or almost no respiration for the CM, while CO2 release reached 7.6 g of CO2/m2 for GW and OMW. Soil organic carbon (SOC) was sustainably improved by 0.54% and 0.50%, respectively, for CM and CP. N mineralization showed no significant difference between amended and untreated soils. Based on these results, compost amendment was the most efficient for C sequestration to enhance soil fertility and consequently reduce the rate of CO2 emission