Ressources hydriques en Algérie du Nord

En Algérie, l'eau revêt un caractère stratégique du fait de sa rareté et d'un cycle naturellement perturbé et déséquilibré. Qu'il s'agisse de l'eau souterraine ou de l'eau de surface, les ressources sont limitées et, compte tenu des problèmes démographiques et de l'occupation de l'espace (sachant que près de 60% de la population algérienne sont concentrés dans la frange septentrionale du territoire qui ne représente que le dixième de la surface totale du pays), d'importants efforts sont nécessaires en matière d'urbanisation intégrée et de gestion rigoureuse dans l'exploitation des réserves, si on veut atteindre la satisfaction des besoins à l'horizon 2010. S'y ajoutent des problèmes de faible mobilisation et de mauvais recyclage par manque de maîtrise des stations d'épuration et l'envasement des retenues.Les 11 bassins versants exoréiques de l'Algérie du Nord couvrant une surface de 130 000 km2 présentent des potentialités en eaux de surface de 11.109 m3 dont seulement 2,13.109 sont mobilisés par les 98 barrages en fonctionnement en 1995. Les besoins estimés à l'horizon 2010 évalués à 9,384. 109 m3 se décomposent en 1,524.109 m3 pour l'eau potable (AEP), 0,23.109 m3 pour l'industrie (AEI) et 7,63.109 m3 pour l'agriculture (AEA) (tableau 6). Sachant que les réserves en eaux souterraines sont évaluées à 1,25.109 m3, le renforcement de la mobilisation des eaux de surface par 3,834. 109 m3 et des eaux souterraines par le captage de 0,33.109 m3 supplémentaires constituent la projection faite en 1995 pour l'horizon 2010 par les différentes institutions publiques intervenant dans la mobilisation et la gestion des ressources en eaux. Cet objectif est déjà fortement entamé en 2002 car fixé dans un contexte de cloisonnement des différentes structures (Hydraulique et Agriculture) et de difficile circulation de l'information entre elles. Il surévalue les capacités de réalisations des barrages, les surfaces à mettre en valeur dans le cadre du programme de développement agricole ainsi que les dotation par habitant en matière d'eau potable. Cette situation constitue un facteur aggravant la difficulté d'une appréhension correcte aussi bien des besoins que des différentes projections sur l'avenir. Les données présentées dans cette synthèse montrent qu'il est désormais impératif que l'aménagement du territoire tienne compte des quantités disponibles afin de rationaliser l'utilisation, la protection de la qualité et la récupération par le recyclage.La qualité chimique des eaux de l'Algérie du Nord est appréciée par les teneurs en nitrates et en chlorures des aquifères côtiers. Cependant, le développement économique et social conduit à une dégradation rapide de cette qualité des eaux, ce qui incite lourdement à œuvrer pour un meilleur recyclage et une meilleur protection des ressources. A défaut, la sanction serait la non satisfaction des besoins en eaux potable, d'irrigation et industrielle. Malheureusement, il semble que l'écart entre disponibilité et besoins soit difficile à réduire. Le but de cet article est de tenter une revue des causes du manque d'eau et des facteurs aggravants.In Algeria, water has a strategic place in economic development, because of its scarcity and a perturbed, non-equilibrated natural cycle. Because of the limited water resources, and the need to meet the demands for the desired quantity and quality of water by the year 2010, planners must develop reasonable alternatives that take into account multiple purposes and objectives. In addition to the growing demography, 60% of the population resides in the northern range of Algeria, which represents one tenth of the total area of the country. Furthermore, inadequate water treatment due to a lack of appropriate technology, siltation of existing dams and limited capacities for water storage hamper the decision-making process.The projected data for year 2010 show structural difficulties and organizational inadequacies that are linked to the multiple operating structures in charge of collecting and conveying the information. The other major difficulty is based on the quality of the information (e.g., empirical methods and a lack of data). For example, the evaporation rate is estimated by the traditional method of a Colorado pan in which the data are mostly discontinuous. The reservoir silt load is evaluated by irregular bathymetric measurements and the results are extrapolated over a year, sometimes from one year to the next. The volume of water losses during water transport and distribution is evaluated for only a very small portion of the network and is then generalized to the entire drinking water and irrigation system.The eleven watersheds of northern Algeria encompass an area of about 130,000 km2 and offer a surface water potential of approximately 11×109 cubic meters (m3) in which only 2.13×109 m3 were collected by 98 functional dams in 1995. According to the forecasts made in 1995, the creation of new reservoirs (17 dams are actually under construction, 25 are about to start construction, and 810 sites for small reservoirs are in the study phase) will increase the mobilized volume of water to about 5.89×109 m3. The silt load for 1995 as estimated by the National Dams Agency (ANB) for all the operational reservoirs corresponded to about 0.02×109 m3. Watershed erosion and the rapid degradation of the forest cover will raise this silt load to 0.482×109 m3. This situation is very alarming for the water resources and consequently in December 2001, the exploitation of major dams (Keddara, Fergoug, Oued Fodda, Ghrib, Beni Amrane, Ksob, Foum el Gherza, Foum el Gueiss) was temporary interrupted. Operations at the Ain Dalia and Hamman Grouz reservoirs were also interrupted in October 2002 due to silt load problems.The water losses from the distribution network, which were estimated around 1.193×109 m3 in 1995, will be reduced to about 0.532×109 m3 in the year 2010 by special renovation programs. The volume of water lost by evaporation represented 0.427×109 m3 in 1995 and will double for year 2010 to reach 0.883×109 m3, according to the ANB.In 1995, groundwater was pumped at a volume of about 0.849×109 m3 from an estimated total reserve of 1.256×109 m3. The urgent program of installing an additional 2000 wells will raise the extracted volume to 1.180×109 m3 by the year 2010. In the northern portion of the country, the water needs will evolve in the following manner : · from 0.791×109 to 1.524×109 m3 per year for drinking water ; · from 1.216×109 to 7.630×109 m3 per year for agricultural needs ; · from 0.120×109 to 0.230×109 m3 per year for industry.It seems clear that the forecast made in 1995 is infeasible and unrealistic. This prediction overevaluates the financial and technical capacities to carry out all the planned projects and also overestimates the land surface for the agricultural development program. The state of water resources and their distribution for the year 2002 already indicate depletion. Accordingly, the following incentive plans were proposed : · Urgent programs for providing potable drinking water from treated seawater for coastal big cities (Algers, Oran, Arzew, and Annaba). This alternative has been implemented starting September 2002 for Annaba and Arzew. · Encouraging and developing agricultural crops that consume less water and encouraging use of modern techniques for irrigation (drop irrigation). · Activating the construction of the 800 planned watershed reservoirs. · Implementing a program for treating and recycling waste waters. The groundwater quality analysis in the northern portion of Algeria, based on the nitrate and chloride concentrations, led to the following conclusion : · Increasing nitrate concentrations for groundwater samples (up to 175 mg×L-1 for Chlef, 200mg×L-1 for Sidi Bel Abbes, and values exceeding the permissible level of 45 mg×L-1 for over half of the sampling points throughout the Mitidja). · The dilution effect during flood events does not overcome the contamination of groundwater by the nitrates. · Most of the coastal aquifers are contaminated by seawater intrusion. The chloride concentration values are about 3,650 mg×L-1 for Algiers region (Mazafran) and sometimes exceed 4,000 mg×L-1 in the eastern portion of the country (Bourchaid, Kissir). · Water samples from dams and large reservoirs were not contaminated by nitrates because of the absence of agricultural activities in the watershed.The degraded water quality and its scarcity complicate the problem of water supply that is already critical in the region.In conclusion, the gap between water needs and the available water resource is very difficult to close. The goal of this article is to review some of the effects of water shortage and its components. The present article emphasizes the need to implement a change in the decision-making process for controlling and managing water. Improved management of water supplies must not only take into account the available water but also has to optimize and rationalize its use. An urgent planning program should also be developed for treating and recycling waste water and for protecting the environment

Doing challenging research studies in a patient centred way: qualitative study to inform a randomised controlled trial in the paediatric emergency care setting

Objective: To inform the design of a randomised controlled trial (called EcLiPSE) to improve the treatment of children with convulsive status epilepticus (CSE). EcLiPSE requires the use of a controversial deferred consent process. Design: Qualitative interview and focus group study. Setting: 8 UK support groups for parents of children who have chronic or acute health conditions and experience of paediatric emergency care. Participants: 17 parents, of whom 11 participated in telephone interviews (10 mothers, 1 father) and 6 in a focus group (5 mothers, 1 father). 6 parents (35%) were bereaved and 7 (41%) had children who had experienced seizures, including CSE. Results: Most parents had not heard of deferred consent, yet they supported its use to enable the progress of emergency care research providing a child's safety was not compromised by the research. Parents were reassured by tailored explanation, which focused their attention on aspects of EcLiPSE that addressed their priorities and concerns. These aspects included the safety of the interventions under investigation and how both EcLiPSE interventions are used in routine clinical practice. Parents made recommendations about the appropriate timing of a recruitment discussion, the need to individualise approaches to recruiting bereaved parents and the use of clear written information. Conclusions: Our study provided information to help ensure that a challenging trial was patient centred in its design. We will use our findings to help EcLiPSE practitioners to: discuss potentially threatening trial safety information with parents, use open-ended questions and prompts to identify their priorities and concerns and clarify related aspects of written trial information to assist understanding and decision-making

Emergency treatment with levetiracetam or phenytoin in status epilepticus in children-the EcLiPSE study: Study protocol for a randomised controlled trial

© The Author(s). 2017. Background: Convulsive status epilepticus (CSE) is the most common life-threatening neurological emergency in childhood. These children are also at risk of significant morbidity, with acute and chronic impact on the family and the health and social care systems. The current recommended first-choice, second-line treatment in children aged 6 months and above is intravenous phenytoin (fosphenytoin in the USA), although there is a lack of evidence for its use and it is associated with significant side effects. Emerging evidence suggests that intravenous levetiracetam may be effective as a second-line agent for CSE, and fewer adverse effects have been described. This trial therefore aims to determine whether intravenous phenytoin or levetiracetam is more effective, and safer, in treating childhood CSE. Methods/design: This is a phase IV, multi-centre, parallel group, randomised controlled, open-label trial. Following treatment for CSE with first-line treatment, children with ongoing seizures are randomised to receive either phenytoin (20 mg/kg, maximum 2 g) or levetiracetam (40 mg/kg, maximum 2.5 g) intravenously. The primary outcome measure is the cessation of all visible signs of CSE as determined by the treating clinician. Secondary outcome measures include the need for further anti-seizure medications or rapid sequence induction for ongoing CSE, admission to critical care areas, and serious adverse reactions. Patients are recruited without prior consent, with deferred consent sought at an appropriate time for the family. The primary analysis will be by intention-to-treat. The primary outcome is a time to event outcome and a sample size of 140 participants in each group will have 80% power to detect an increase in CSE cessation rates from 60% to 75%. Our total sample size of 308 randomised and treated participants will allow for 10% loss to follow-up. Discussion: This clinical trial will determine whether phenytoin or levetiracetam is more effective as an intravenous second-line agent for CSE, and provide evidence for management recommendations. In addition, this trial will also provide data on which of these therapies is safer in this setting

Pediatric brain tumor cancer stem cells: cell cycle dynamics, DNA repair, and etoposide extrusion

Reliable model systems are needed to elucidate the role cancer stem cells (CSCs) play in pediatric brain tumor drug resistance. The majority of studies to date have focused on clinically distinct adult tumors and restricted tumor types. Here, the CSC component of 7 newly established primary pediatric cell lines (2 ependymomas, 2 medulloblastomas, 2 gliomas, and a CNS primitive neuroectodermal tumor) was thoroughly characterized. Comparison of DNA copy number with the original corresponding tumor demonstrated that genomic changes present in the original tumor, typical of that particular tumor type, were retained in culture. In each case, the CSC component was approximately 3–4-fold enriched in neurosphere culture compared with monolayer culture, and a higher capacity for multilineage differentiation was observed for neurosphere-derived cells. DNA content profiles of neurosphere-derived cells expressing the CSC marker nestin demonstrated the presence of cells in all phases of the cell cycle, indicating that not all CSCs are quiescent. Furthermore, neurosphere-derived cells demonstrated an increased resistance to etoposide compared with monolayer-derived cells, having lower initial DNA damage, potentially due to a combination of increased drug extrusion by ATP-binding cassette multidrug transporters and enhanced rates of DNA repair. Finally, orthotopic xenograft models reflecting the tumor of origin were established from these cell lines. In summary, these cell lines and the approach taken provide a robust model system that can be used to develop our understanding of the biology of CSCs in pediatric brain tumors and other cancer types and to preclinically test therapeutic agents

Presentations of children to emergency departments across Europe and the COVID-19 pandemic: A multinational observational study

BACKGROUND: During the initial phase of the Coronavirus Disease 2019 (COVID-19) pandemic, reduced numbers of acutely ill or injured children presented to emergency departments (EDs). Concerns were raised about the potential for delayed and more severe presentations and an increase in diagnoses such as diabetic ketoacidosis and mental health issues. This multinational observational study aimed to study the number of children presenting to EDs across Europe during the early COVID-19 pandemic and factors influencing this and to investigate changes in severity of illness and diagnoses. METHODS AND FINDINGS: Routine health data were extracted retrospectively from electronic patient records of children aged 18 years and under, presenting to 38 EDs in 16 European countries for the period January 2018 to May 2020, using predefined and standardized data domains. Observed and predicted numbers of ED attendances were calculated for the period February 2020 to May 2020. Poisson models and incidence rate ratios (IRRs), using predicted counts for each site as offset to adjust for case-mix differences, were used to compare age groups, diagnoses, and outcomes. Reductions in pediatric ED attendances, hospital admissions, and high triage urgencies were seen in all participating sites. ED attendances were relatively higher in countries with lower SARS-CoV-2 prevalence (IRR 2.26, 95% CI 1.90 to 2.70, p < 0.001) and in children aged <12 months (12 to <24 months IRR 0.86, 95% CI 0.84 to 0.89; 2 to <5 years IRR 0.80, 95% CI 0.78 to 0.82; 5 to <12 years IRR 0.68, 95% CI 0.67 to 0.70; 12 to 18 years IRR 0.72, 95% CI 0.70 to 0.74; versus age <12 months as reference group, p < 0.001). The lowering of pediatric intensive care admissions was not as great as that of general admissions (IRR 1.30, 95% CI 1.16 to 1.45, p < 0.001). Lower triage urgencies were reduced more than higher triage urgencies (urgent triage IRR 1.10, 95% CI 1.08 to 1.12; emergent and very urgent triage IRR 1.53, 95% CI 1.49 to 1.57; versus nonurgent triage category, p < 0.001). Reductions were highest and sustained throughout the study period for children with communicable infectious diseases. The main limitation was the retrospective nature of the study, using routine clinical data from a wide range of European hospitals and health systems. CONCLUSIONS: Reductions in ED attendances were seen across Europe during the first COVID-19 lockdown period. More severely ill children continued to attend hospital more frequently compared to those with minor injuries and illnesses, although absolute numbers fell. TRIAL REGISTRATION: ISRCTN91495258 https://www.isrctn.com/ISRCTN91495258

Specialist healthcare services for concussion/mild traumatic brain injury in England: a consensus statement using modified Delphi methodology

Objective To establish a consensus on the structure and process of healthcare services for patients with concussion in England to facilitate better healthcare quality and patient outcome. Design This consensus study followed the modified Delphi methodology with five phases: participant identification, item development, two rounds of voting and a meeting to finalise the consensus statements. The predefined threshold for agreement was set at ≥70%. Setting Specialist outpatient services. Participants Members of the UK Head Injury Network were invited to participate. The network consists of clinical specialists in head injury practising in emergency medicine, neurology, neuropsychology, neurosurgery, paediatric medicine, rehabilitation medicine and sports and exercise medicine in England. Primary outcome measure A consensus statement on the structure and process of specialist outpatient care for patients with concussion in England. Results 55 items were voted on in the first round. 29 items were removed following the first voting round and 3 items were removed following the second voting round. Items were modified where appropriate. A final 18 statements reached consensus covering 3 main topics in specialist healthcare services for concussion; care pathway to structured follow-up, prognosis and measures of recovery, and provision of outpatient clinics. Conclusions This work presents statements on how the healthcare services for patients with concussion in England could be redesigned to meet their health needs. Future work will seek to implement these into the clinical pathway

Presentations of children to emergency departments across Europe and the COVID-19 pandemic: A multinational observational study

During the initial phase of the Coronavirus Disease 2019 (COVID-19) pandemic, reduced numbers of acutely ill or injured children presented to emergency departments (EDs). Concerns were raised about the potential for delayed and more severe presentations and an increase in diagnoses such as diabetic ketoacidosis and mental health issues. This multinational observational study aimed to study the number of children presenting to EDs across Europe during the early COVID-19 pandemic and factors influencing this and to investigate changes in severity of illness and diagnoses. Routine health data were extracted retrospectively from electronic patient records of children aged 18 years and under, presenting to 38 EDs in 16 European countries for the period January 2018 to May 2020, using predefined and standardized data domains. Observed and predicted numbers of ED attendances were calculated for the period February 2020 to May 2020. Poisson models and incidence rate ratios (IRRs), using predicted counts for each site as offset to adjust for case-mix differences, were used to compare age groups, diagnoses, and outcomes. Reductions in pediatric ED attendances, hospital admissions, and high triage urgencies were seen in all participating sites. ED attendances were relatively higher in countries with lower SARS-CoV-2 prevalence (IRR 2·26, 95% CI 1·90 to 2·70, p < 0.001) and in children aged <12 months (12 to <24 months IRR 0·86, 95% CI 0·84 to 0·89; 2 to <5 years IRR 0·80, 95% CI 0·78 to 0·82; 5 to <12 years IRR 0·68, 95% CI 0·67 to 0·70; 12 to 18 years IRR 0·72, 95% CI 0·70 to 0·74; versus age <12 months as reference group, p < 0.001). The lowering of pediatric intensive care admissions was not as great as that of general admissions (IRR 1·30, 95% CI 1·16 to 1·45, p < 0.001). Lower triage urgencies were reduced more than higher triage urgencies (urgent triage IRR 1·10, 95% CI 1·08 to 1·12; emergent and very urgent triage IRR 1·53, 95% CI 1·49 to 1·57; versus nonurgent triage category, p < 0.001). Reductions were highest and sustained throughout the study period for children with communicable infectious diseases. The main limitation was the retrospective nature of the study, using routine clinical data from a wide range of European hospitals and health systems. Reductions in ED attendances were seen across Europe during the first COVID-19 lockdown period. More severely ill children continued to attend hospital more frequently compared to those with minor injuries and illnesses, although absolute numbers fell. ISRCTN91495258 https://www.isrctn.com/ISRCTN91495258