This study investigates the health implications of sharing a shisha (hookah) mouthpiece during smoking, with a focus on tuberculosis (TB) and hepatitis prevalence in Sub Saharan Africa. It examines shisha smoking beha...This study investigates the health implications of sharing a shisha (hookah) mouthpiece during smoking, with a focus on tuberculosis (TB) and hepatitis prevalence in Sub Saharan Africa. It examines shisha smoking behavior patterns and associated risks of disease transmission among those sharing a common mouthpiece. Through literature review and empirical data analysis, the research highlights epidemiological factors driving TB and hepatitis transmission within the context of shisha smoking in Sub Saharan Africa. Exploring cultural, social, and behavioral determinants influencing shisha mouthpiece sharing, the study offers insights into interventions and public health strategies. It emphasizes the need for targeted health education campaigns, policy interventions, and community-based initiatives to promote safer smoking practices. Immediate coordinated public health interventions, including educational campaigns and regulatory measures, are recommended. Collaboration among healthcare professionals, policymakers, and communities is essential. These insights deepen the understanding of challenges posed by communal shisha smoking in Sub Saharan Africa, laying the groundwork for evidence-based interventions to reduce TB and hepatitis transmission and enhance overall health outcomes in the region. This research underscores the urgency of addressing the risks associated with shisha smoking, aiming to mitigate disease transmission and improve population health in Sub Saharan Africa.展开更多
This study was conducted in southern Tunisia in the growing seasons of 2013 and 2014, and aimed to compare the effects of exotic and endogenous shrub species （Haloxylon persicum and Retama raetam, respectively） on u...This study was conducted in southern Tunisia in the growing seasons of 2013 and 2014, and aimed to compare the effects of exotic and endogenous shrub species （Haloxylon persicum and Retama raetam, respectively） on understory vegetation and soil nutrients. For each shrub species, the canopied sub-habitat （under the shrub crown） and un-canopied sub-habitat （in open grassland area） were distinguished. The concentrations of soil nutrients （organic matter, total nitrogen and extractable phosphorus） were found to be significantly higher （P〈0.05） under R. raetam canopy than under H. persicum canopy and in open area. The result also showed that the presence of shrubs improved all the values of understory vegetation parameters （floristic composition, density, total plant cover and dry matter） and all these values were significantly higher under endogenous species canopy than under exotic species canopy. These results highlighted the positive effect of endogenous shrubs on understory vegetation and soil nutrients compared to the exotic ones in the Saharan areas of Tunisia.展开更多
Airborne particulate matter （PM） is of health and environmental concern not only in highly urbanized areas, but also in rural areas that are used for intensive agricultural purposes, In this study, PM size- segregat...Airborne particulate matter （PM） is of health and environmental concern not only in highly urbanized areas, but also in rural areas that are used for intensive agricultural purposes, In this study, PM size- segregated samples were collected simultaneously for 12 months in a small town （Belle Glade, Florida）, which is the center of a vast sugarcane growing area and at Delray Beach, a coastal city in Palm Beach County, Florida. During the winter sampling period, when sugarcane foliage is burned just before harvest- ing to reduce the amount of plant matter to be handled, PM10 levels were 50% or higher than otherwise measured, indicating that sugarcane harvesting and processing is a major local source for PM10. For the rest of the year, PM10 levels at both sites are similar, suggesting that ambient PM levels at both sites are impacted by the major urban centers in Southern Florida. During late July and early August, the PM10 levels at both sites were substantially elevated and revealed the typical red-brownish color of Saharan dust. This has been reported to occur frequently with suitable meteorological conditions over the Atlantic Ocean coupled with a Sahara dust storm event. During the sugarcane harvesting season at Belle Glade, the concentrations of PAHs associated with PM10 were up to 15 times higher than those measured during the summer growing season, indicating a substantially higher exposure of the rural population to these often mutagenic and carcinogenic compounds.展开更多
Respiratory diseases such as asthma and rhinitis are multifaceted disorders which are exacerbated by various factors including: gender, age, diet, genetic background, biological materials, allergens (pollen and spores...Respiratory diseases such as asthma and rhinitis are multifaceted disorders which are exacerbated by various factors including: gender, age, diet, genetic background, biological materials, allergens (pollen and spores), pollutants, meteorological conditions and dust particles. It is hypothesized that, the number of valid physician diagnosed cases of paediatric asthma, which has resulted in emergency room visits in Trinidad can be expressed as a function of the magnitude of pollen counts, particulate matter (PM10), and selected meteorological parameters. These parameters were used to develop a 7-day predictive model for paediatric asthma admittance. The data showed no obvious, strong correlations between paediatric asthma admissions and dust concentrations, and paediatric asthma admissions and pollen concentrations, when considered in isolation or in a linear fashion. However, using polynomial regression analysis, which looked at combinations of interactions, a strong 7-day predictive model for paediatric asthma admissions, was developed. The model was tested against actual data collated during the study period and showed a strong correlation (R<sup>2</sup> = 0.85) between the regression model and the actual admissions data.展开更多
Atmospheric Infrared Sounder （AIRS） data show that the Saharan air layer （SAL） is a dry, warm, and well-mixed layer between 950 and 500 hPa over the tropical Atlantic, extending westward from the African coast to ...Atmospheric Infrared Sounder （AIRS） data show that the Saharan air layer （SAL） is a dry, warm, and well-mixed layer between 950 and 500 hPa over the tropical Atlantic, extending westward from the African coast to the Caribbean Sea. The formations of both Hurricane Isabel and Tropical Depression 14 （TD14） were accompanied with outbreaks of SAL air during the period 1-12 September 2003, although TD14 failed to develop into a named tropical cyclone. The influence of the SAL on their formations is investigated by examining data from satellite observations and numerical simulations, in which AIRS data are incorporated into the MM5 model through the nudging technique. Analyses of the AIRS and simulation data suggest that the SAL may have played two roles in the formation of tropical cyclones during the period 1-12 September 2003. First, the outbreaks of SAL air on 3 and 8 September enhanced the transverse-vertical circulation with the rising motion along the southern edge of the SAL and the sinking motion inside the SAL, triggering the development of two tropical disturbances associated with Hurricane Isabel and TD14. Second, in addition to the reduced environmental humidity and enhanced static stability in the lower troposphere, the SAL dry air intruded into the inner region of these tropical disturbances as their cyclonic ？ows became strong. This effect may have slowed down the formation of Isabel and inhibited TD14 becoming a named tropical cyclone, while the enhanced vertical shear contributed little to tropical cyclone formation during this period. The 48-h trajectory calculations confirm that the parcels from the SAL can be transported into the inner region of an incipient tropical cyclone.展开更多
Introduction: The Covid-19 pandemic is a public health emergency characterized by severe acute respiratory distress syndrome. It has many clinical forms and affects all age groups. Despite the magnitude of this pandem...Introduction: The Covid-19 pandemic is a public health emergency characterized by severe acute respiratory distress syndrome. It has many clinical forms and affects all age groups. Despite the magnitude of this pandemic, data from pediatric cohorts in Cameroon remain sparse. Objective: The aim of this study was to describe the clinical presentation of Covid-19 in the pediatric population of the Nkolndongo health district. Materials and method: A cross-sectional study was conducted for a duration of 5 months from January to May 2021 and covered a period of 9 months (March to December 2020). All patients aged 0 to 19 years, suspected of having Covid-19, confirmed by real-time RT-PCR targeting the N and ORF1 ab viral genes and managed in the Nkolndongo health district were included. The results were analyzed using IBM SPSS.23.0 software and the data expressed as frequencies, percentages, and means. The threshold of statistical significance was set at 0.05. Results: This study revealed that 48 patients out of 154 suspected cases were tested positive. The most affected age group was adolescents aged 13 - 19 years (92.85%). The most frequent symptoms were cough (33%), fever (42%) and nasal discharge (25%). Infants were the least affected. 58% of patients were asymptomatic, 47.91% were in mild stage, 8.33% in moderate stage and 4.16% in severe stage. All the children tested positive survived. Patients with comorbidity were 20 times more likely to develop moderate to severe clinical forms, this being statistically significant. Conclusion: The clinical presentation reported mainly fever, cough and anterior nasal discharge. There was a significant association between the presence of comorbidity and the moderate to severe degrees of severity.展开更多
For decades, Taenia solium cysticercosis (TSC) has remained an important constraint for public health and economic well being of the predisposed communities. Despite the fact that the disease is easily preventable, hu...For decades, Taenia solium cysticercosis (TSC) has remained an important constraint for public health and economic well being of the predisposed communities. Despite the fact that the disease is easily preventable, humans remain foci for transmission. They harbour the mature form of the parasite (Taenia solium) which may be curable at this stage and also easily prevented from contaminating pig feeds and environment with eggs of the parasite to break the cycle. Researchers, knowledgeable communities and international organisations such as the World Health Organisation work hard to make the disease a history. Nevertheless, persistence of the disease in endemic regions such as sub Saharan Africa is kept on increasing. While TSC in human may serve as a silent killer as it can go unnoticed for years, the immanent social cultural settings and lifestyles of the communities in endemic areas form the main concern on the epidemiology of the disease. Unless lifestyles change in endemic regions, front line research might rarely find its way into applications in an area of huge societal and economic impact, the TSC epidemiology. Sincerely, transmission of TSC is favoured by poor sanitation and hygiene which is motivated by lifestyle and poverty. What is perhaps missing is the knowledge on “why is the communities involved ease indiscriminately while almost every member of the community in endemic areas knows that indiscriminate defecation may harm their health? What social drivers are behind this motive (bush defecation)? How best can the disease be controlled and monitored? This review recommends for developing and implementing an interdisciplinary OneHealth community-based control mechanism and monitoring (surveillance) programme as standpoints towards eliminating TSC in sub-Saharan Africa and the rest endemic regions.展开更多
The implementation of a program on routine antenatal anti-D prophylaxis (RAADP) in the developed world has led to a significant decline in the residual numbers of Rhesus negative women becoming sensitized. However, a ...The implementation of a program on routine antenatal anti-D prophylaxis (RAADP) in the developed world has led to a significant decline in the residual numbers of Rhesus negative women becoming sensitized. However, a significant number of Rhesus D negative women in SSA are not fortunate because of lack of access to prophylactic immunoglobulin D and thus they continue to be affected. The management of Rhesus negative pregnancy in Sub-Saharan Africa is associated with several daunting challenges: absence of a policy on universal access to Rh D immunoglobulin, lack of fetomaternal testing facilities, unaffordability of prophylactic anti-D immunoglobulin, poor uptake of quality antenatal care, poor health infrastructure, sub optimal management of potentially sensitizing events during pregnancy, shortage of qualified medical personnel, poor data management, high incidence of illegal abortion and quackery. There is a need for the formulation of necessary guidelines on Rhesus immunoprophylaxis in SSA. Health authorities need to implement evidence-based policy on universal access to anti-D immunoglobulin. There is also the need to optimize the knowledge of obstetricians on anti-D prophylaxis, implementation of the readily available and affordable Kleihauer fetomaternal haemorrhage testing for all women who experience a potentially sensitizing event antenatally post 20 weeks gestation and postnatally. These factors can facilitate the effective management of Rh negative pregnancy in the region and reduce the risk of Rhesus D immunization and Rhesus D haemolytic disease of the foetus and newborn.展开更多
Background: The Tubu are nomadic people who live in remote parts of the central Sahara, primarily in the Tibesti massif(Chad), and in both Northeastern Niger and Southern Libya. All of these areas are close to become ...Background: The Tubu are nomadic people who live in remote parts of the central Sahara, primarily in the Tibesti massif(Chad), and in both Northeastern Niger and Southern Libya. All of these areas are close to become conflict zones. However, no data about the Tubu's health and sanitary status are currently available, which would be of major concern if humanitarian interventions would become required.Methods: In 1970, the "Mission Anthropologique Belge au Niger"(MABN) investigated a Tubu tribe named Broaya that lived at Seguedine and Djado on the northeastern rim of the Tenere desert. One hundred fifty-one adult volunteers answered an oral questionnaire and underwent a medical examination, followed by the collection of blood thin films and samples of urine and stool. The environmental fauna of medical importance was also studied.Results: Albeit 43 year-old, these results have not been previously published. The estimated age of death for fathers was approximately 56 years, and that for mothers was 60 years. On average, each married woman had had 4.7 children. The overall perinatal mortality rate was 232 ‰, the overall infant mortality rate was 153 ‰, and the overall child mortality rate was 99 ‰. The mean height was 164.1 cm and 157.4 cm, the mean weight was 50.1 kg and 47.9kg, and the mean blood pressure was 131/78 mm Hg and 127/75 mm Hg for males and females, respectively. The physical examination found 6 cases of blindness(4.0%). Five subjects presented with an elevated blood pressure(3.3%), and 5(3.3%) displayed an abnormal thoracic auscultation evocative of tuberculosis or of an acute lung infection. The abdominal examination and renal palpation found 5 large masses(3.3%), and 2 subjects had a palpable enlarged spleen(1.3%). The blood thin films were fixed in methanol and subsequently examined in Toulouse. The search for blood parasites was negative. The urine samples were centrifuged and then microscopically examined in the field. No blood-fluke eggs were found. The stool samples were mixed with a prese展开更多
In a context of increasing competition and sustainable development, service prices and unused capacity enhancement play a crucial role in freight or people transportation management. The focus of the paper is on a Dia...In a context of increasing competition and sustainable development, service prices and unused capacity enhancement play a crucial role in freight or people transportation management. The focus of the paper is on a Dial-a-ride Problem in the Saharan country context, for the particular of Taxi “woro-woro”1. More precisely, these taxis help to transport groups of people without any affinity, from point A to point B without stopping. Also, we propose for this problem an exact solution based on a mix integer program (MIP). A secondary study on a random instance generation algorithm is presented, which allows us to have a diversified and varied benchmark on which to apply our MIP program.展开更多
The following study of populations of gerbil in arid and Saharan terrain enables us toexamine the relationships between the essential determinants in the cycles of abundance. Social unity, methods of spatial distribut...The following study of populations of gerbil in arid and Saharan terrain enables us toexamine the relationships between the essential determinants in the cycles of abundance. Social unity, methods of spatial distribution, dispersal, strategies for food and repro-duction, and also disappearance, are linked to climatic factors and defined according to therecognised hierarchy of stages of perceptions in Ecology individual, group, population,展开更多
The seasonal transport of the Saharan dust to the West African region, near the Gulf of Guinea, during northem winter has been studied over 12 years. Using an optical particle counter, the dust aerosols in the diamete...The seasonal transport of the Saharan dust to the West African region, near the Gulf of Guinea, during northem winter has been studied over 12 years. Using an optical particle counter, the dust aerosols in the diameter range 0.5-25 μm have been sampled at Kumasi （6040＇ N, l°34＇ W） in Ghana during the winter months of January-February from 1997 to 2009. The settling atmospheric dust particles observed during the peak Harmattan and the background Harmattan periods are analysed for the mean particle size, number and mass concentrations as well as the particle size-frequency. It is shown that the average daily particle diameter, number and mass concentrations obtained in the peak Harmattan periods are 1.57 ± 0.54 μm, 50 ± 25 particles/cm3 and 1,130 ± 994 μg/m3, respectively, while for the background Harmattan these values are correspondingly, 1.31 ±0.31 μm, 32 ±12 particles/cm3 and 576 ±429 μg/m3, respectively. These experimental results will be useful for the design of ambient air-filters and for understanding the West African climate change.展开更多
The interdecadal variability of precipitation over sub-Saharan Africa (SSA) and central North China (CNC) is examined and compared in this study. Previous studies have found that the two regions have similar interdeca...The interdecadal variability of precipitation over sub-Saharan Africa (SSA) and central North China (CNC) is examined and compared in this study. Previous studies have found that the two regions have similar interdecadal dry–wet evolution in the past 100 years. The results show obvious decadal precipitation fluctuations in the two regions. In CNC, a persistent negative precipitation anomaly is detected from the early 1970s to the 2000s. In SSA, a negative precipitation anomaly is apparent since the late 1970s, while a distinct upward trend is found since the 1990s although the precipitation anomaly is still negative. Significant correlation is found between the decadal precipitation anomalies in SSA and the SST modes (Atlantic Multidecadal Oscillation (AMO) and Pacific Decadal Oscillation (PDO)), as well as the North Atlantic Oscillation (NAO), while in CNC the decadal precipitation is influenced by the NAO and PDO. The EOF results show that the total explained variance of the first four EOFs in SSA is smaller than that of CNC. The fourth and third modes in SSA are significantly associated with the AMO and PDO respectively, while the first, third, and fourth modes are significantly associated with the NAO. The first mode in CNC is significantly associated with the NAO. The first mode of the precipitation anomaly in SSA fluctuates out of phase with that in CNC, while in-phase changes are apparent among the third and the fourth modes.展开更多
The current study focuses on the contribution of the dromedary in the preservation and increase of spontaneous flora through seeds transfer by endozoochory. Thus dromedary faeces have been collected in selected area o...The current study focuses on the contribution of the dromedary in the preservation and increase of spontaneous flora through seeds transfer by endozoochory. Thus dromedary faeces have been collected in selected area of region of Ghardaia （Northern Algeria Sahara）, since it is one of the three known cameline rangelands during the four successive seasons of the years 2009-2010, in order to examine their seed contents. Our investigation allowed us to invento 1,832 seeds representing 33 different types varying according to the seasons of harvest. The biggest density of seeds was present in summer with 986 seeds, against 424 seeds in winter, 366 seeds in fall and 56 seeds in spring, and of the same way, the biggest number of types was present in summer with 30 types, consistent of the fall season with 26 types, and arrived then the season of winter with 20 types and the one of spring with five types. The gotten results allowed us to appreciate the ecological role of this animal in the desertic ecosystem in the dissemination and the proliferation of the seeds of the spontaneous flora in its fragile and hostile desert environment to the survival of the seeds enveloped in its faeces.展开更多
Haboob occurrence strongly impacts the annual variability of airborne desert dust in North Africa.In fact,more dust is raised from erodible surfaces in the early summer(monsoon)season when deep convective storms are c...Haboob occurrence strongly impacts the annual variability of airborne desert dust in North Africa.In fact,more dust is raised from erodible surfaces in the early summer(monsoon)season when deep convective storms are common but soil moisture and vegetation cover are low.On 27 June 2018,a large dust storm is initiated over North Africa associated with an intensive westward dust transport.Far away from emission sources,dust is transported over the Atlantic for the long distance.Dust plume is emitted by a strong surface wind and further becomes a type of haboob when it merges with the southwestward deep convective system in central Mali at 0200 UTC(27 June).We use satellite observations to describe and estimate the dust mass concentration during the event.Approximately 93%of emitted dust is removed the dry deposition from the atmosphere between sources(10°N–25°N;1°W–8°E)and the African coast(6°N–21°N;16°W–10°W).The convective cold pool has induced large economic and healthy damages,and death of animals in the northeastern side of Senegal.ERA5 reanalysis has shown that the convective mesoscale impacts strongly the climatological location of the Saharan heat low(SHL).展开更多
BACKGROUND Insulin resistance(IR)is the main complication found in 35%-80%of women with polycystic ovary syndrome(PCOS).However,there is no definite consensus regarding which marker to use for its assessment in PCOS w...BACKGROUND Insulin resistance(IR)is the main complication found in 35%-80%of women with polycystic ovary syndrome(PCOS).However,there is no definite consensus regarding which marker to use for its assessment in PCOS women.Research has shown that hyperinsulinemia is correlated with increased bone mass.Given that most women with PCOS are insulin resistant,which is independent from body fat and characterized by hyperinsulinemia,it could be hypothesized that there would be an increased bone mass in the patient as a result.Subsequently,increased bone mass could be measured using the wrist circumference method.AIM To assess the wrist circumference as an easy-to-detect marker of IR in Congolese women with PCOS.METHODS Seventy-two Congolese women with PCOS and seventy-one controls from the same ethnic group,were enrolled in the study(mean age 24.33±5.36 years).Fasting biochemical parameters,and the Homeostasis Model Assessment of insulin resistance(HOMA-IR)and body composition were evaluated.The nondominant wrist circumference was measured manually,as was the waist circumference(WC),hip circumference,height and weight.Calculated measures included evaluation of body mass index(BMI),Waist-to-Height(WHtR)and Waist-to-hip ratio(WHR).In addition,body composition was assessed by Bioelectrical Impedance Analysis using a body fat analyzer.RESULTS The non-dominant wrist circumference was more closely correlated with HOMAIR(r=0.346;P=0.003)and was the best anthropometrical marker correlated with IR(P=0.011)compared with other anthropometrical markers in women with PCOS:Dominant Wrist Circumference(r=0.315;P=0.007),Waist Circumference(WC)(r=0.259;P=0.028),BMI(r=0.285;P=0.016),WHR(r=0.216;P=0,068)and WHtR(r=0.263;P=0.027).The diagnostic accuracy of the non-dominant wrist circumference for the presence or absence of IR using Receiver-operating characteristic(ROC)curve analysis showed that the area under the ROC curve was 0.72.A cutoff value for the non-dominant wrist circumference of 16.3 cm was found to be the best predictor of IR 展开更多
文摘This study investigates the health implications of sharing a shisha (hookah) mouthpiece during smoking, with a focus on tuberculosis (TB) and hepatitis prevalence in Sub Saharan Africa. It examines shisha smoking behavior patterns and associated risks of disease transmission among those sharing a common mouthpiece. Through literature review and empirical data analysis, the research highlights epidemiological factors driving TB and hepatitis transmission within the context of shisha smoking in Sub Saharan Africa. Exploring cultural, social, and behavioral determinants influencing shisha mouthpiece sharing, the study offers insights into interventions and public health strategies. It emphasizes the need for targeted health education campaigns, policy interventions, and community-based initiatives to promote safer smoking practices. Immediate coordinated public health interventions, including educational campaigns and regulatory measures, are recommended. Collaboration among healthcare professionals, policymakers, and communities is essential. These insights deepen the understanding of challenges posed by communal shisha smoking in Sub Saharan Africa, laying the groundwork for evidence-based interventions to reduce TB and hepatitis transmission and enhance overall health outcomes in the region. This research underscores the urgency of addressing the risks associated with shisha smoking, aiming to mitigate disease transmission and improve population health in Sub Saharan Africa.
文摘This study was conducted in southern Tunisia in the growing seasons of 2013 and 2014, and aimed to compare the effects of exotic and endogenous shrub species （Haloxylon persicum and Retama raetam, respectively） on understory vegetation and soil nutrients. For each shrub species, the canopied sub-habitat （under the shrub crown） and un-canopied sub-habitat （in open grassland area） were distinguished. The concentrations of soil nutrients （organic matter, total nitrogen and extractable phosphorus） were found to be significantly higher （P〈0.05） under R. raetam canopy than under H. persicum canopy and in open area. The result also showed that the presence of shrubs improved all the values of understory vegetation parameters （floristic composition, density, total plant cover and dry matter） and all these values were significantly higher under endogenous species canopy than under exotic species canopy. These results highlighted the positive effect of endogenous shrubs on understory vegetation and soil nutrients compared to the exotic ones in the Saharan areas of Tunisia.
文摘Airborne particulate matter （PM） is of health and environmental concern not only in highly urbanized areas, but also in rural areas that are used for intensive agricultural purposes, In this study, PM size- segregated samples were collected simultaneously for 12 months in a small town （Belle Glade, Florida）, which is the center of a vast sugarcane growing area and at Delray Beach, a coastal city in Palm Beach County, Florida. During the winter sampling period, when sugarcane foliage is burned just before harvest- ing to reduce the amount of plant matter to be handled, PM10 levels were 50% or higher than otherwise measured, indicating that sugarcane harvesting and processing is a major local source for PM10. For the rest of the year, PM10 levels at both sites are similar, suggesting that ambient PM levels at both sites are impacted by the major urban centers in Southern Florida. During late July and early August, the PM10 levels at both sites were substantially elevated and revealed the typical red-brownish color of Saharan dust. This has been reported to occur frequently with suitable meteorological conditions over the Atlantic Ocean coupled with a Sahara dust storm event. During the sugarcane harvesting season at Belle Glade, the concentrations of PAHs associated with PM10 were up to 15 times higher than those measured during the summer growing season, indicating a substantially higher exposure of the rural population to these often mutagenic and carcinogenic compounds.
文摘Respiratory diseases such as asthma and rhinitis are multifaceted disorders which are exacerbated by various factors including: gender, age, diet, genetic background, biological materials, allergens (pollen and spores), pollutants, meteorological conditions and dust particles. It is hypothesized that, the number of valid physician diagnosed cases of paediatric asthma, which has resulted in emergency room visits in Trinidad can be expressed as a function of the magnitude of pollen counts, particulate matter (PM10), and selected meteorological parameters. These parameters were used to develop a 7-day predictive model for paediatric asthma admittance. The data showed no obvious, strong correlations between paediatric asthma admissions and dust concentrations, and paediatric asthma admissions and pollen concentrations, when considered in isolation or in a linear fashion. However, using polynomial regression analysis, which looked at combinations of interactions, a strong 7-day predictive model for paediatric asthma admissions, was developed. The model was tested against actual data collated during the study period and showed a strong correlation (R<sup>2</sup> = 0.85) between the regression model and the actual admissions data.
基金supported by the Ty-phoon Research Project (2009CB421503) of the National Basic Research Program (the 973 Program) of Chinathe National Science Foundation of China (NSFC grant no 408750387)the Social Commonweal Research Program of the Ministry of Science and Technology of the People’s Republic of China (GYHY200806009)
文摘Atmospheric Infrared Sounder （AIRS） data show that the Saharan air layer （SAL） is a dry, warm, and well-mixed layer between 950 and 500 hPa over the tropical Atlantic, extending westward from the African coast to the Caribbean Sea. The formations of both Hurricane Isabel and Tropical Depression 14 （TD14） were accompanied with outbreaks of SAL air during the period 1-12 September 2003, although TD14 failed to develop into a named tropical cyclone. The influence of the SAL on their formations is investigated by examining data from satellite observations and numerical simulations, in which AIRS data are incorporated into the MM5 model through the nudging technique. Analyses of the AIRS and simulation data suggest that the SAL may have played two roles in the formation of tropical cyclones during the period 1-12 September 2003. First, the outbreaks of SAL air on 3 and 8 September enhanced the transverse-vertical circulation with the rising motion along the southern edge of the SAL and the sinking motion inside the SAL, triggering the development of two tropical disturbances associated with Hurricane Isabel and TD14. Second, in addition to the reduced environmental humidity and enhanced static stability in the lower troposphere, the SAL dry air intruded into the inner region of these tropical disturbances as their cyclonic ？ows became strong. This effect may have slowed down the formation of Isabel and inhibited TD14 becoming a named tropical cyclone, while the enhanced vertical shear contributed little to tropical cyclone formation during this period. The 48-h trajectory calculations confirm that the parcels from the SAL can be transported into the inner region of an incipient tropical cyclone.
文摘Introduction: The Covid-19 pandemic is a public health emergency characterized by severe acute respiratory distress syndrome. It has many clinical forms and affects all age groups. Despite the magnitude of this pandemic, data from pediatric cohorts in Cameroon remain sparse. Objective: The aim of this study was to describe the clinical presentation of Covid-19 in the pediatric population of the Nkolndongo health district. Materials and method: A cross-sectional study was conducted for a duration of 5 months from January to May 2021 and covered a period of 9 months (March to December 2020). All patients aged 0 to 19 years, suspected of having Covid-19, confirmed by real-time RT-PCR targeting the N and ORF1 ab viral genes and managed in the Nkolndongo health district were included. The results were analyzed using IBM SPSS.23.0 software and the data expressed as frequencies, percentages, and means. The threshold of statistical significance was set at 0.05. Results: This study revealed that 48 patients out of 154 suspected cases were tested positive. The most affected age group was adolescents aged 13 - 19 years (92.85%). The most frequent symptoms were cough (33%), fever (42%) and nasal discharge (25%). Infants were the least affected. 58% of patients were asymptomatic, 47.91% were in mild stage, 8.33% in moderate stage and 4.16% in severe stage. All the children tested positive survived. Patients with comorbidity were 20 times more likely to develop moderate to severe clinical forms, this being statistically significant. Conclusion: The clinical presentation reported mainly fever, cough and anterior nasal discharge. There was a significant association between the presence of comorbidity and the moderate to severe degrees of severity.
文摘For decades, Taenia solium cysticercosis (TSC) has remained an important constraint for public health and economic well being of the predisposed communities. Despite the fact that the disease is easily preventable, humans remain foci for transmission. They harbour the mature form of the parasite (Taenia solium) which may be curable at this stage and also easily prevented from contaminating pig feeds and environment with eggs of the parasite to break the cycle. Researchers, knowledgeable communities and international organisations such as the World Health Organisation work hard to make the disease a history. Nevertheless, persistence of the disease in endemic regions such as sub Saharan Africa is kept on increasing. While TSC in human may serve as a silent killer as it can go unnoticed for years, the immanent social cultural settings and lifestyles of the communities in endemic areas form the main concern on the epidemiology of the disease. Unless lifestyles change in endemic regions, front line research might rarely find its way into applications in an area of huge societal and economic impact, the TSC epidemiology. Sincerely, transmission of TSC is favoured by poor sanitation and hygiene which is motivated by lifestyle and poverty. What is perhaps missing is the knowledge on “why is the communities involved ease indiscriminately while almost every member of the community in endemic areas knows that indiscriminate defecation may harm their health? What social drivers are behind this motive (bush defecation)? How best can the disease be controlled and monitored? This review recommends for developing and implementing an interdisciplinary OneHealth community-based control mechanism and monitoring (surveillance) programme as standpoints towards eliminating TSC in sub-Saharan Africa and the rest endemic regions.
文摘The implementation of a program on routine antenatal anti-D prophylaxis (RAADP) in the developed world has led to a significant decline in the residual numbers of Rhesus negative women becoming sensitized. However, a significant number of Rhesus D negative women in SSA are not fortunate because of lack of access to prophylactic immunoglobulin D and thus they continue to be affected. The management of Rhesus negative pregnancy in Sub-Saharan Africa is associated with several daunting challenges: absence of a policy on universal access to Rh D immunoglobulin, lack of fetomaternal testing facilities, unaffordability of prophylactic anti-D immunoglobulin, poor uptake of quality antenatal care, poor health infrastructure, sub optimal management of potentially sensitizing events during pregnancy, shortage of qualified medical personnel, poor data management, high incidence of illegal abortion and quackery. There is a need for the formulation of necessary guidelines on Rhesus immunoprophylaxis in SSA. Health authorities need to implement evidence-based policy on universal access to anti-D immunoglobulin. There is also the need to optimize the knowledge of obstetricians on anti-D prophylaxis, implementation of the readily available and affordable Kleihauer fetomaternal haemorrhage testing for all women who experience a potentially sensitizing event antenatally post 20 weeks gestation and postnatally. These factors can facilitate the effective management of Rh negative pregnancy in the region and reduce the risk of Rhesus D immunization and Rhesus D haemolytic disease of the foetus and newborn.
文摘Background: The Tubu are nomadic people who live in remote parts of the central Sahara, primarily in the Tibesti massif(Chad), and in both Northeastern Niger and Southern Libya. All of these areas are close to become conflict zones. However, no data about the Tubu's health and sanitary status are currently available, which would be of major concern if humanitarian interventions would become required.Methods: In 1970, the "Mission Anthropologique Belge au Niger"(MABN) investigated a Tubu tribe named Broaya that lived at Seguedine and Djado on the northeastern rim of the Tenere desert. One hundred fifty-one adult volunteers answered an oral questionnaire and underwent a medical examination, followed by the collection of blood thin films and samples of urine and stool. The environmental fauna of medical importance was also studied.Results: Albeit 43 year-old, these results have not been previously published. The estimated age of death for fathers was approximately 56 years, and that for mothers was 60 years. On average, each married woman had had 4.7 children. The overall perinatal mortality rate was 232 ‰, the overall infant mortality rate was 153 ‰, and the overall child mortality rate was 99 ‰. The mean height was 164.1 cm and 157.4 cm, the mean weight was 50.1 kg and 47.9kg, and the mean blood pressure was 131/78 mm Hg and 127/75 mm Hg for males and females, respectively. The physical examination found 6 cases of blindness(4.0%). Five subjects presented with an elevated blood pressure(3.3%), and 5(3.3%) displayed an abnormal thoracic auscultation evocative of tuberculosis or of an acute lung infection. The abdominal examination and renal palpation found 5 large masses(3.3%), and 2 subjects had a palpable enlarged spleen(1.3%). The blood thin films were fixed in methanol and subsequently examined in Toulouse. The search for blood parasites was negative. The urine samples were centrifuged and then microscopically examined in the field. No blood-fluke eggs were found. The stool samples were mixed with a prese
文摘In a context of increasing competition and sustainable development, service prices and unused capacity enhancement play a crucial role in freight or people transportation management. The focus of the paper is on a Dial-a-ride Problem in the Saharan country context, for the particular of Taxi “woro-woro”1. More precisely, these taxis help to transport groups of people without any affinity, from point A to point B without stopping. Also, we propose for this problem an exact solution based on a mix integer program (MIP). A secondary study on a random instance generation algorithm is presented, which allows us to have a diversified and varied benchmark on which to apply our MIP program.
文摘The following study of populations of gerbil in arid and Saharan terrain enables us toexamine the relationships between the essential determinants in the cycles of abundance. Social unity, methods of spatial distribution, dispersal, strategies for food and repro-duction, and also disappearance, are linked to climatic factors and defined according to therecognised hierarchy of stages of perceptions in Ecology individual, group, population,
文摘The seasonal transport of the Saharan dust to the West African region, near the Gulf of Guinea, during northem winter has been studied over 12 years. Using an optical particle counter, the dust aerosols in the diameter range 0.5-25 μm have been sampled at Kumasi （6040＇ N, l°34＇ W） in Ghana during the winter months of January-February from 1997 to 2009. The settling atmospheric dust particles observed during the peak Harmattan and the background Harmattan periods are analysed for the mean particle size, number and mass concentrations as well as the particle size-frequency. It is shown that the average daily particle diameter, number and mass concentrations obtained in the peak Harmattan periods are 1.57 ± 0.54 μm, 50 ± 25 particles/cm3 and 1,130 ± 994 μg/m3, respectively, while for the background Harmattan these values are correspondingly, 1.31 ±0.31 μm, 32 ±12 particles/cm3 and 576 ±429 μg/m3, respectively. These experimental results will be useful for the design of ambient air-filters and for understanding the West African climate change.
基金the Chinese Academy of SciencesThe World Academy of Sciences(CAS-TWAS)for financial support+1 种基金provided by the National Key R&D Program of China [grant number 2016YFA0600404]the National Natural Science Foundation of China [grant number41530532]
文摘The interdecadal variability of precipitation over sub-Saharan Africa (SSA) and central North China (CNC) is examined and compared in this study. Previous studies have found that the two regions have similar interdecadal dry–wet evolution in the past 100 years. The results show obvious decadal precipitation fluctuations in the two regions. In CNC, a persistent negative precipitation anomaly is detected from the early 1970s to the 2000s. In SSA, a negative precipitation anomaly is apparent since the late 1970s, while a distinct upward trend is found since the 1990s although the precipitation anomaly is still negative. Significant correlation is found between the decadal precipitation anomalies in SSA and the SST modes (Atlantic Multidecadal Oscillation (AMO) and Pacific Decadal Oscillation (PDO)), as well as the North Atlantic Oscillation (NAO), while in CNC the decadal precipitation is influenced by the NAO and PDO. The EOF results show that the total explained variance of the first four EOFs in SSA is smaller than that of CNC. The fourth and third modes in SSA are significantly associated with the AMO and PDO respectively, while the first, third, and fourth modes are significantly associated with the NAO. The first mode in CNC is significantly associated with the NAO. The first mode of the precipitation anomaly in SSA fluctuates out of phase with that in CNC, while in-phase changes are apparent among the third and the fourth modes.
文摘The current study focuses on the contribution of the dromedary in the preservation and increase of spontaneous flora through seeds transfer by endozoochory. Thus dromedary faeces have been collected in selected area of region of Ghardaia （Northern Algeria Sahara）, since it is one of the three known cameline rangelands during the four successive seasons of the years 2009-2010, in order to examine their seed contents. Our investigation allowed us to invento 1,832 seeds representing 33 different types varying according to the seasons of harvest. The biggest density of seeds was present in summer with 986 seeds, against 424 seeds in winter, 366 seeds in fall and 56 seeds in spring, and of the same way, the biggest number of types was present in summer with 30 types, consistent of the fall season with 26 types, and arrived then the season of winter with 20 types and the one of spring with five types. The gotten results allowed us to appreciate the ecological role of this animal in the desertic ecosystem in the dissemination and the proliferation of the seeds of the spontaneous flora in its fragile and hostile desert environment to the survival of the seeds enveloped in its faeces.
基金This work is supported by UK Research and Innovation as part of the Global Challenges Research Fund,African SWIFT programme,grant number NE/P021077/1,The Agence Nationale de l’Aviation civile et de la Météorologie(ANACIM),ICARE Data and services center,University of Lille,the National Aeronautics and Space Administration(NASA)and National Oceanic and Atmospheric Administration(NOAA)are owed for sharing ground observations and satellite data.
文摘Haboob occurrence strongly impacts the annual variability of airborne desert dust in North Africa.In fact,more dust is raised from erodible surfaces in the early summer(monsoon)season when deep convective storms are common but soil moisture and vegetation cover are low.On 27 June 2018,a large dust storm is initiated over North Africa associated with an intensive westward dust transport.Far away from emission sources,dust is transported over the Atlantic for the long distance.Dust plume is emitted by a strong surface wind and further becomes a type of haboob when it merges with the southwestward deep convective system in central Mali at 0200 UTC(27 June).We use satellite observations to describe and estimate the dust mass concentration during the event.Approximately 93%of emitted dust is removed the dry deposition from the atmosphere between sources(10°N–25°N;1°W–8°E)and the African coast(6°N–21°N;16°W–10°W).The convective cold pool has induced large economic and healthy damages,and death of animals in the northeastern side of Senegal.ERA5 reanalysis has shown that the convective mesoscale impacts strongly the climatological location of the Saharan heat low(SHL).
文摘BACKGROUND Insulin resistance(IR)is the main complication found in 35%-80%of women with polycystic ovary syndrome(PCOS).However,there is no definite consensus regarding which marker to use for its assessment in PCOS women.Research has shown that hyperinsulinemia is correlated with increased bone mass.Given that most women with PCOS are insulin resistant,which is independent from body fat and characterized by hyperinsulinemia,it could be hypothesized that there would be an increased bone mass in the patient as a result.Subsequently,increased bone mass could be measured using the wrist circumference method.AIM To assess the wrist circumference as an easy-to-detect marker of IR in Congolese women with PCOS.METHODS Seventy-two Congolese women with PCOS and seventy-one controls from the same ethnic group,were enrolled in the study(mean age 24.33±5.36 years).Fasting biochemical parameters,and the Homeostasis Model Assessment of insulin resistance(HOMA-IR)and body composition were evaluated.The nondominant wrist circumference was measured manually,as was the waist circumference(WC),hip circumference,height and weight.Calculated measures included evaluation of body mass index(BMI),Waist-to-Height(WHtR)and Waist-to-hip ratio(WHR).In addition,body composition was assessed by Bioelectrical Impedance Analysis using a body fat analyzer.RESULTS The non-dominant wrist circumference was more closely correlated with HOMAIR(r=0.346;P=0.003)and was the best anthropometrical marker correlated with IR(P=0.011)compared with other anthropometrical markers in women with PCOS:Dominant Wrist Circumference(r=0.315;P=0.007),Waist Circumference(WC)(r=0.259;P=0.028),BMI(r=0.285;P=0.016),WHR(r=0.216;P=0,068)and WHtR(r=0.263;P=0.027).The diagnostic accuracy of the non-dominant wrist circumference for the presence or absence of IR using Receiver-operating characteristic(ROC)curve analysis showed that the area under the ROC curve was 0.72.A cutoff value for the non-dominant wrist circumference of 16.3 cm was found to be the best predictor of IR
