Thriving green havens in baking deserts:Plant diversity and species composition of urban plantations in the Sahara Desert

Hot arid zones represent vital reservoirs of unique species and ecosystems,holding significant importance for biodiversity.This study aimed to explore the plant diversity associated with tree plantations in urban ecosystems under hyper-arid climatic conditions in the Sahara Desert of Algeria.In May 2022,30 quadrats measuring 1 m^(2) each were established at the base of Phoenix dactylifera,Leucaena leucocephala,and Tamarix aphylla,corresponding to the dominant tree species in each of three plantations.In each quadrat,the plant quantitative inventory was conducted to measure plant diversity and similarity among the studied plantations.Based on this,we assessed the plant functional traits and rarity/abundance status of the flora.The findings revealed a diverse flora associated with the studied plantations,comprising 29 plant species grouped into 27 genera and 12 families.Notably,Poaceae(accounting for 30.8% of the flora),Asteraceae(25.0%),and Zygophyllaceae(21.6%)were well-represented.With an overall density of approximately 555 individuals/m^(2),Zygophyllum album(120 individuals/m^(2))and Polypogon monspeliensis(87 individuals/m^(2))emerged as the most abundant species.Functional trait analysis underscored the pivotal role of therophytes(constituting over 50.0% of the flora)and anemochorous species(33.0%-62.5%).Phytogeographic analysis emphasized the prevalence of the Saharo-Arabic element(constituting over 31.0% of the flora)and the Mediterranean Saharo-Arabic element(9.5%-21.5%).The Cosmopolitan element thrived under disturbance factors,recording percentages from 13.0% to 20.0% of the plant community.The rarity/abundance status of the flora emphasized the significance of rare,common,and very common species in the studied plantations.These findings could provide fundamental data for the effective control and management of biodiversity in hot hyper-arid urban ecosystems.

LASIK术后Sahara沙粒综合征的临床研究进展

Sahara沙粒综合征是准分子激光原位角膜磨削术 (L ASIK)后发生于角膜板层间的一种非特异性炎症 ,通常出现于术后 1～ 6天 ,其发生机制尚不清楚 ,据国外研究其病因与手术环境的污染有关 ,激素治疗效果明显 。

RSSP-I、RSSP-Ⅱ及SAHARA三种安全通信协议实现技术简介

针对RSSP-I、RSSP-Ⅱ、SAHARA 3种安全通信协议的主要安全通信技术实现机制进行介绍,并对这3种安全协议进行多方面比对,从而便于研发人员可根据具体应用场景选取所需的安全协议或防护技术。

Pre-Hospital Management of Craniocerebral Trauma in South Saharan Africa: Cotonou Experience

The management of craniocerebral trauma begins at the site of the accident. This is one of the diseases for which pre-hospital care is well codified. The objective of this study is to report the experience of the Emergency Aid Medical Service (EMAS) of BENIN in the pre-hospital management of craniocerebral trauma. 146 head injuries were cared for. 116 were male. The mean age was 32 years with extremes ranging from 2 to 77 years. Etiology in 68% of patients was a public road accident. And the request for the use of the EMAS was made by highway users for 41% of the injuries. About 5.5% were severe cranio-brain injuries, more than 75% of which had died in intensive care. In 77% of the EMAS interventions, there was an intensive care physician in the team. 34 wounded had been transported in a vacuum mattress. The rigid cervical collar was used in 8 major traumas. All the wounded were transported by ambulance. The duration of hospitalization varied from a few hours in the emergency department to 90 days in the hospital ward. 9 patients died. One of them, who died in an ambulance, was a woman. The prehospital medical care of head trauma in BENIN is still progressing.

Abrupt Change in Sahara Precipitation and the Associated Circulation Patterns

This study investigates the changes in inter-annual summer precipitation and the relationship with the atmospheric general circulation in the Sahara Desert occurred in the last 40 years (1971-2010). The results show that the summer precipitation undergone in drought recovery with a strong abrupt change at the end of 20th century. This change in Sahara precipitation is subsequently accompanied with the changes in the atmospheric circulation. The Sahara drought recovery is associated with a significant warming in the tropical and extratropical sea surface temperature, which led to the increase in moisture budget of the tropical African monsoon. The remarkable features such as the strengthening in Arctic high and mid-latitude upper level westerly wind, weakening in subpolar low and upper tropospheric zonal wind over North Africa have shown a distinct relationship with the Sahara precipitation changes.

CLIMATIC CHANGE AND HUMAN ACTIVITIES OF NORTHEASTERN SAHARA IN HOLOCENE

Chronology establishment and dating data analyses on lacustrine deposits in northeastern Sahara show that vast fresh lakes existed over there between 9900-2400 a B.P. Especially, great continuous lakes developed and got their maximum extent during the period from 9800 a B.P. to 6450 a B.P. From 6000 a B.P. to 3600 a B.P., the evolution of the lakes experienced a new stage with a property of drastic fluctuations and a periodicity of 600 years, which was the response to the climatic environment changes. On the aspect of the relation between natural environment and the human, the warm humid period in the Holocene was not only a very important time for human development and evolution, but also was a moment for human reproduction and division. On the other hand, this warm humid period was also a distinguished time to natural environment changes, the accumulation of the strong weathered debris and fine materials formed the basements for the formation of the Sahara Desert.

SAHARA效用函数下的保险人的最优投资策略

在本文中,我们考虑带有SAHARA效用函数的保险人的最优投资策略,目标是最大化其终端财富效用.这类效用函数拥有非单调的绝对风险厌恶,比CARA和CRRA效用函数更加灵活.在风险过程和股票过程分别由布朗运动和几何布朗运动刻画的情形下,我们采用鞅方法分别得到了临界值为常数和临界值动态服从一个明确过程的情况下的显示解.最后,我们证明最优投资策略是状态独立的.

Severity of the Rheumatoid Arthritis in Sub-Saharan Africa:Study of 403 Senegalese Observations

Introduction: We assess the severity of the rheumatoid arthritis in a Senegalese African black population. Patients and methods: It is a retrospective study achieved in the service of Internal Medicine of Aristide Le Dantec teaching hospital of Dakar between January 2005 and December 2016 in patients suffering from rheumatoid arthritis. We specified for every patient the predictive data of severity of the rheumatoid arthritis. Results: Four hundred and three patients have been gathered (39 men and 364 women), with the mean age of 45.8 years. An active tobacco addiction was noticed in 10 patients. The diagnostic delay was on average of 72 months. Characteristic articular deformations were noticed in 215 patients (53.3%). They were correlated to male (p = 0.038), to age (p = 0.001) and to the activity of the rheumatoid arthritis (p = 0.0445). Systemic manifestations have been observed in 213 cases (52.9%), particularly anemia (50.8%). They were correlated to the anti-CCP antibodies (p = 0.047). The ESR was increased at the first hour in 84.4% of cases (median: 43 mm;extreme: 1and 160). CRP was elevated in 63.71% of cases (median of 12 mg/l;extreme: 1 and 384). The rheumatoid factor was positive in 57.6% of the cases. The anti-CCP antibodies were present in 89.2% of the cases. Articular erosions were objectified in all cases. A DAS 28 superior to 5.1 was noticed in 71% of cases. Conclusion: The rheumatoid arthritis was severe in our study.

Temporal changes in seasonal precipitation over the Sahara Desert from 1979 to 2016

Rainfall variability dominates livelihoods in all countries of Saharan Africa.To better understand the processes involved in Sahara precipitation changes,we used the Global Precipitation Climatology Center(GPCC)dataset to examine dry and wet seasonal trends in the Sahara region from 1979 to 2016.We also used the European Centre for Medium-Range Weather Forecasts(ECMWF)to evaluate the general atmospheric circulation associated with seasonal change of Sahara precipitation.The Mann-Kendall test and Theil sens'slope estimator methods were adopted to test and estimate the significance and weight of precipitation trend,respectively.The results revealed that Sahara precipitation has increased significantly.The seasonal evaluation shows a positive trend of 0.42 mm/decade and 1.43 mm/decade in JAS(June,August,and September)seasons for the northern and southern Saharan Desert,respectively.Moreover,the JFMA(January,February,March,and April)period shows a negative trend but not statistically significant.An examination of the general circulation and moisture transport changes suggested an increase of rainfall in southern Sahara.The wet period is also driven by northward penetration of moisture originating from the Sahel region,African Easterly Jet(AEJ),and weakening in the upper tropospheric zonal wind.Summer rainfall has also been likely associated with positive anomalies of sea surface temperature(SST)in the North Tropical Atlantic(NTA)and the Mediterranean Sea.

Global Climate Change Impacts on Human Health in Sub-Sahara Africa

Health and climate have been linked since antiquity.The impact of climate change on human health has received increasing recognition since it was first mentioned in the IRCC(Intergovernmental Report on Climate Change).Climate change is widely considered to be a major driver of inter-annual variability of malaria incidence in Africa.Several researches have suggested that climate can affect infectious disease patterns because disease agents

The Desert Spontaneous Plants Used in Saharan Phytotherapy： Case of Tidikelt Region

The local plant resources adapted to the desert harsh geomorphologicl environment are a landmark that characterizes the Saharan region： erg, dunes, and wadis. This work emphasizes on some results obtained through a study conducted in 2011, based on surveys and field observations in the Tidikelt oases （in Salah, wilaya of Tamenrasset） which is implanted in the south of Algeria. The objective was the study of traditional herbal medicine using the spontaneous medicinal herbs, which constitute one of the socio-cultural aspects of Saharan society in Algeria. Traditional medicine is one reflect of the knowledge and how to live of the local population. Desert people know the various herbs ＇Achebe＇, and its nomenclature. They indicated their site or places of local presence, as well as its own peculiarities and their uses. Our goal is to contribute in enhancing the interest of valorization of these plants in the therapeutic and eventually industrial uses. For that, we need to integrate this perspective into local economic development policies valuing the diversity of plant resources from Tidikelt in the Algerian Sahara.

Ecology, Biology and Biometry of an Endemic Fabaceae： Genista Saharae Cosson and Durieu

Genista saharae Cosson and Durieu, endemic Saharan Africa, is a spontaneous fabaceae dunes south of M＇sila （Algeria）. Perfectly adapted to arid and sandy soils, this species is a remarkable plant for dune fixation and thus fights against desertification. The objective of this study is to provide local species to various development programs of steppe ecological systems in nature and therefore ensure the rehabilitation of these species while considering the conservation of biodiversity and sustainable management of biological resources steppe. After a field survey and stratified sampling, the methodological approach has taken into account three types of analysis： a biometric analysis of a population of 100 individuals of this species, the second analysis on its biology at last an analysis of an ecological factor dealing with the accuracy governing the distribution of this species in Maiter Oued in the south of M＇sila. The results have clarified the ecology of this species to better understand its biology and to develop statistically a diagnosis on the phenology and morphology of various organs （pods, seeds, leaves） of Genista saharae Cosson and Durieu.

Laboratory Evaluation of the Stiffness Modulus of a Modified Bituminous Concrete with PR PLAST Sahara

Uneven roads surface can be observed on bituminous pavements. This is due to moving loads and climate conditions. If the observed deformations exceed the elastic limit, important damages can occur, so new materials are used to improve the stiffness modulus of bituminous mixtures. To achieve this, a modified bituminous concrete by addition of the PR PLAST Sahara （produced by PR industries and PLAST for Plastic） mainly used in arid region has been studied. The use of this additive at various percentages 0.1, 0.3, 0.6 and 0.9 by weight of bituminous concrete has been investigated to determine its stiffness modulus. An experimental design using the Taguchi tables has been elaborated to reduce the number of tests. Marshall and NAT （Nottingham asphalt tester） tests have been carried out, and a mathematical model of the stiffness modulus has been proposed.

Modelling Electricity Generation and Capacity with CO₂Emissions for Sub Saharan Africa

In this investigation the electricity generation and the electricity capacity of energy mix for sub Saharan Africa from 2020 to 2040 including CO2 emission from (coal, oil, gas) (Total Final Consumption, transport) and power generation were analyzed. These energy sources include conventional and renewable energy sources such as coal, oil, gas, hydro, nuclear, bioenergy, solar PV, and other renewables. We developed a linear regression equation based on the least-square method of estimation to forecast the value of energy and CO2 emission. We fit a linear trend to the energy time series including CO2 emission to show how simple linear regression analysis can be used to forecast future value. The predicted results from 2020 to 2040 show that the electricity capacity and the electricity generation from gas, hydro, solar PV and other renewables will dominate compared to nuclear and bioenergy. Some forms of energies contributions such as nuclear and bioenergy will remain insignificant. The gas will continue to emit a lot carbon dioxide compared to the emission from oil and coal. The emission of CO2 from total final consumption (TFC) of oil will be high compared to its emission from power generation (PG) and transport. The least squares estimated regression equation adequately describes the relationship between Energy or CO2 emission and time period with a high R-squared. This approach of modeling in a linear regression, the energy and CO2 emission simplifies significantly the analysis to help policy makers underlying reasons for the trends to develop appropriate strategies for the future, may be useful to assess the sustained economic development and transformation that require a definition of electricity access in those countries.

Veterinary Laboratory Diagnosis: A Missed Opportunity in the Continuum of Care for Veterinarians in Selected Countries in Sub-Sahara Africa

In Africa, sustainable livestock production must address food security, as well as animal disease concerns simultaneously in addition to social aspects. Livestock disease challenges seem to be increasing with one of them being lack of good animal diagnostics services with notable emerging zoonotic diseases which if not correctly diagnosed in animals pose risks to humans. The major livestock hubs in sub-Sahara Africa (SSA) include Uganda, Ethiopia, Tanzania and Nigeria and utilization of diagnostic services by veterinarians in these countries could inform further action by different stakeholders in the SSA region. A cross sectional survey with veterinarians was conducted between January 2022 and February 2022 to determine the number of veterinarians who have submitted samples for veterinary diagnosis, laboratory utilization rates and challenges faced by veterinarians using veterinary labs in sub-Sahara Africa between the period of 2018 and 2022. Methods: This was a cross sectional study, where an online questionnaire was shared with veterinarians through their online social group networks in different countries and data was captured and analyzed. Results: 74% (64/87) of veterinarians reported having submitted a sample to a lab, Government labs were the most utilized at 54%, followed by private labs at 37% and the human health labs recorded 9% utilization rate. The most faced challenge by veterinarians was failing to get samples to the lab because the labs where far (52%) with the least challenge reported being failure to understand the lab results at 3%. Conclusion: Government labs were the most utilized in this period, however notable challenges like failing to get samples to the lab still exist. Veterinary diagnosis is still an underutilized service in sub-Sahara Africa and more measures need to be worked on in terms of sample logistics, capacity building and trainings of both lab personnel and veterinarians in interpretation of results to ensure improved utilization of veterinary diagnostics services.

Fighting in the Sahara

Project Manager of the Liaohe Branch, Bureau of Geophysical Prospecting, Inc., China National Petroleum Corporation(BGP): This man undertakes an incredibly important task of the BGP: he firmly occupies the market in Cameroon and operates the company in a healthy manner. During his tenure, the international exploration market was in the downturn. He led his team to overcome difficulties and persevered in market development, and through close cooperation, he won the trust of the Cameroon National Oil Company and other international oil companies.

Frequency of Monthly Ejaculation at Sexual Intercourse, DNA Fragmentation Index and Fertilization Rate among Sperm Donors and Fertility-Challenged Men in Sub-Saharan Africa: Paper 2

Introduction: Heterogenous sexual intercourse often produces a powerful orgasm that stimulates the pituitary function. Studies have suggested ejaculation frequency based on age. Materials and Methods: Semi-structured questionnaires were used to collect information from subjects. Semen samples were collected from sperm donors and sub-fertile men who presented for infertility challenges. Processing and analysis of semen samples were done according to World Health Organization (WHO) guidelines. Sperm deoxyribonucleic acid (DNA) fragmentation was evaluated using the Halosperm kit. Results: Among sperm donors, those aged χ2 = 0.09, P-value = 0.81, OR = 3.2, 95% CI: 0.23, 45.19) while among sub-fertile men those aged ≥40 years were approximately 2.3 times more likely to have very low frequency of MESI compared to aged χ2 = 2.11, P-value = 0.51, OR = 2.27, 95% CI: 0.74, 9.92). The frequency of all categories of MESI was highest among sub-fertile men aged χ2 = 0.03, P-value = 0.57, OR = 2.42, 95% CI: 0.41, 14.46). Sub-fertile men aged ≥40 with diastolic hypertension (≥90 mmHg) were approximately 6 times more likely to have a low (6 - 10) frequency of MESI compared to those aged χ2 = 1.97, P-value = 0.16, OR = 6.22, 95% CI: 0.69, 55.77). Overall mean fertilization rate was significantly higher (t-test = 2.44, P-value = 0.01) among sub-fertile men aged Conclusion: Cigarette smoking, more than alcohol consumption, appears to be a major factor that significantly affects the frequency of MESI among sub-fertile men in all age groups. Frequency of MESI negatively but insignificantly correlated with systolic blood pressure.

Barriers and facilitators for early and exclusive breastfeeding in health facilities in Sub-Saharan Africa:a systematic review

Background:Sub-Saharan Africa carries a disproportionate burden of under-five child deaths in the world and appropriate breastfeeding practices can support efforts to reduce child mortality rates.Health facilities are important in the promotion of early and exclusive breastfeeding.The purpose of this review was to examine facility-based barriers and facilitators to early and exclusive breastfeeding in Sub-Saharan Africa.Methods:A systematic search was conducted on Medline,Web of Science,CINAHL,African Journals Online and African Index Medicus from database inception to April 29,2021 and primary research studies on breastfeeding practices in health facilities in Sub-Saharan Africa were included in the review.We assessed qualitative studies with the Critical Appraisal Skills Programme Qualitative Checklist and quantitative studies using the National Heart,Lung,and Blood Institute tool.The review protocol was registered to Prospero prior to conducting the review(CRD42020167414).Results:Of the 56 included studies,relatively few described health facility infrastructure and supplies-related issues(5,11%)while caregiver factors were frequently described(35,74%).Facility-based breastfeeding policies and guidelines were frequently available but challenged by implementation gaps,especially at lower health service levels.Facilitators included positive caregiver and health worker attitudes,knowledge and support during the postpartum period.Current studies have focused on caregiver factors,particularly around their knowledge and attitudes,while health facility infrastructure and supplies factors appear to be growing concerns,such as overcrowding and lack of privacy during breastfeeding counselling that lowers the openness and comfort of mothers especially those HIV-positive.Conclusion:There has been a dramatic rise in rates of facility births in Sub-Saharan Africa,which must be taken into account when considering the capacities of health facilities to support breastfeeding practices.As the number of facility births rise in Sub-Saharan Africa,so does the responsibility of skilled healthcare workers to provide the necessary breastfeeding support and advice to caregivers.Our review highlighted that health facility infrastructure,supplies and staffing appears to be a neglected area in breastfeeding promotion and a need to strengthen respectful maternity care in the delivery of breastfeeding counselling,particularly in supporting HIV-positive mothers within the context of Sub-Saharan Africa.

基于OpenStack Sahara集群的高可用性的设计与实现

针对目前大数据处理环境成本高,存在点单故障等问题,使用Open Stack Sahara可以将云计算与大数据结合起来.设计出一种基于Open Stack Sahara集群的高可用性方案,验证结果显示,该方案解决了单点故障问题,实现了自动故障切换,保证了集群的高可用性,从而提高了Sahara集群的性能.

Preliminary comparative study of anti-inlfammatory effect of unheated and heat-treated Sahara honey:In vivo approach

Objective:To investigate the effect of unheated and heat-treated of Sahara honey.Methods:A total of 24 Swiss albino mice weighing 25-35 g were divided into four groups(n=6).Anti-inflammatory effect was assessed at 1,2,3,4,5 and 6 h after subplantar injection of carrageenan(0.5 mL of a 1%solution in normal saline).In addition,total phenolic content was determined by modified Folin-Ciocalteu method.Results:The total phenolic content capacity of the Sahara honey before and after heat treatment was between 72 and 97.9 mg of gallic acid equivalents/100 g of honey respectively.Administration of unheated honey(oral administration)reduced significantly(P<0.05).The carrageenan induced mice paw edema model at 1,3 and 6 h for 21.85%,5.43%and 80.43%,respectively.Administration of heat-treated honey showed insignificant inhibition of carrageenan and induced paw edema at 1 h(31.16%),3 h(0.25%)and 6 h(34.19%).The 50 mg/kg diclofenac exhibited percent reduction in paw volume 16.12%,8.90%and 15.32%after 1 h,3 h and 6 h,respectively,when compared with control animals.No toxicity was identified.Conclusions:Our results suggest that unheated Sahara honey has anti-inflammatory effects by reducing the mice paw edema size while heat-treated Sahara honey decreases the antiinflammatory activity.