86 research outputs found
Recommended from our members
Future prospects of the renewable energy sector in libya
This study investigates the options available to the energy sector in Libyan, particularly in relation to the potential of using renewable energy as one of the main sources for the country. Libyan government has set a target for renewable energy resources sharing with current energy sources to reach 30% by the year 2030 which mainly includes wind energy, Concentrating Solar Power (CSP), Photovoltaic (PV) and Solar Water Heating (SWH). The argument here is not whether this can be completed or not within the stipulated time. But the main objective is achieving a sustainable economic growth through a clean energy system and for the energy supply to maintain meeting the growing energy demand. The aim of this paper is to illustrate the current energy supply and future demands in Libya. This paper integrates data from literature review, field visits and interviews with Libyan energy experts to paint a comprehensive picture in relation to energy demand and consumption. The findings which have emerged from the analysis of this data reflect energy challenges and opportunities in Libya. Furthermore, securing alternative resources of energy and income are becoming critically important for Libya and other countries within the Middle East and North Africa region (MENA) if they wish to maintain the same standard of living for future generations and reduce pollution, fossil fuel local consumption and carbon emission
Morphology of Intestinal Goblet Cells of The Dromedary (Camelus dromedarius)
Morphology of the goblet cells in the intestine of the dromedary (Camelus dromedarius ) was carried out by light and electron microscopes. Histologically, the goblet cells appeared as globular or ovoidshaped with basally located flat nuclei. They were dispersed among the columnar cells lining the epithelia of the villi and crypts of Lieberkuhn, and they increased greatly in number towards the rectum. Goblet cells showed positive reaction to (PAS) stain. Ultrastructurally, the scanning electron microscopy showed villi with rough surface which displayed goblet cells and microvilli in the small intestine. In the large intestine, the surface of the mucosal fold was characteristically covered by goblet cells and epithelial cells. The ultrastructure of the goblet cells showed the cell membrane lacked microvilli and the cytoplasm contained numerous large spherical granules of mucin, rough endoplasmic reticulum and mitochondria. The nucleus containing eccentric nucleolus, chromatin and heterochromatin materials.Key words: dromedary, goblet cells, intestine, morpholog
Recommended from our members
Investigation into the feasibility of the utilisation of renewable energy resources in Libya
Renewable energy in Libya, in particular solar and wind energy, can partly cover current local energy demands. It can also, through connections to the Middle East, Africa and Europe, provide neighbouring countries with electricity. Additionally, with the increase in energy demand around the world, and the international effort to reduce carbon emissions from fossil fuels, there has been a drive in many oil-rich countries to diversify their energy portfolios and resources. Libya is currently interested in utilising its renewable energy resources in order to reduce the financial and energy dependency on oil reserves. This research investigates the current utilisation and the future of renewable energy in Libya, and the challenges and opportunities for investment in renewable energy in Libya. This study has explored the possibility of utilising the available renewable energy resources in Libya to offer the Libyan government a strategy for providing sustainable energy resources. This is expected to reduce carbon emissions, and help achieve an economically, socially and environmentally sustainable energy future. Interviews have been conducted with managers, consultants and decision makers from different government organisations, and have included energy policy makers, energy generation companies and major energy consumers. A comprehensive survey has been conducted to evaluate several characteristics of domestic energy demand and energy consumption in Libya. The findings have indicated that, despite the recent political changes and the challenges that face the implementation of renewable energy technologies in Libya, renewable energy opportunities are still strategically of high importance. Solar and wind energy are considered the main sources of renewable energy for Libya. It has been found that energy demand is increasing in Libya and that renewable energy could be a solution to cover some of this demand. In addition, the results have indicated that there are no clear policies that support the implementation of renewable energy projects within Libya, and no clear legislation aimed at the types of technical, commercial and environmental issues which must be addressed for the implementation of renewable energy projects in Libya. Legislations governing the legal support for facilitating the spread of renewable energy in Libya are also limited. Moreover, there is a need to attract investors in renewable technologies by enhancing the country's infrastructure and improving the existing investment regulations
Effets d’éthanol sur la fertilité du lapin mâle adulte Oryctolagus cuniculus
La consommation chronique d'éthanol est associée à des troubles de la reproduction chez l’homme. Pour cela, l’objectif de ce travail est d’évaluer chez le lapin mâle adulte Oryctolagus cuniculus l’effet de la consommation chronique d’éthanol sur la reproduction. L’alcool concentré à 20%, 25% et 30% a été administré au lapin mâle par gavage pendant six semaines successives. Après sacrifice des animaux, les testicules et l’épididyme ont été prélevés afin d’évaluer certains paramètres de la reproduction, alors que le sang a été recueilli pour le dosage de la testostérone. Les résultats obtenus montrent une diminution de la mobilité, la vitesse, la vitalité et la concentration des spermatozoïdes, accompagnée d’une augmentation de leur nombre malformés chez les trois lots d’animaux traités par rapport au lot témoin. Par ailleurs, le traitement à l’alcool a entrainé une diminution du poids des testicules et de l’épididyme, ainsi qu’une diminution du taux de la testostérone chez les animaux des groupes traités comparés au groupe témoin. Les résultats montrent clairement que l’éthanol exerce un effet toxique sur la fertilité du lapin mâle.© 2015 International Formulae Group. All rights reserved.Mots clés: Alcool, épididyme, spermatozoïde, testicule, testostéroneEnglish AbstractChronic ethanol consumption is associated with reproductive disorders in humans. Therefore, the objective of this study was to evaluate in adult male rabbit Oryctolagus cuniculus the effect of chronic ethanol consumption on reproduction. The concentrated alcohol 20%, 25% and 30% was administered to male rabbits by gavage for six successive weeks. After sacrificing the animals, testis and epididymis were collected to assess certain parameters of the reproduction, while the blood was collected for the determination of testosterone. The results show a decrease in mobility, speed, vitality and spermatozoa concentration, accompanied by an increase in the number of malformed spermatozoa in three batches of treated animals compared to the control group. Moreover, the treatment with alcohol resulted in a decreased weight of the testes and epididymis, and decreased testosterone levels in animals treated groups compared to the control group. The results clearly show that ethanol exerts a toxic effect on the fertility of male rabbit.© 2015 International Formulae Group. All rights reserved.Keywords: Alcohol, epididymis, spermatozoa, testis, testosterone
Development and evaluation of real-time loop-mediated isothermal amplification assay for rapid detection of cystic echinococcosis
Mycobacterium tuberculosis whole genome sequencing provides insights into the Manila strain and drug-resistance mutations in the Philippines.
The Philippines has a high incidence of tuberculosis disease (TB), with an increasing prevalence of multidrug-resistant Mycobacterium tuberculosis (MDR-TB) strains making its control difficult. Although the M. tuberculosis "Manila" ancient lineage 1 strain-type is thought to be prevalent in the country, with evidence of export to others, little is known about the genetic diversity of circulating strains. By whole genome sequencing (WGS) 178 isolates from the Philippines National Drug Resistance Survey, we found the majority (143/178; 80.3%) belonged to the lineage 1 Manila clade, with the minority belonging to lineages 4 (European-American; n = 33) and 2 (East Asian; n = 2). A high proportion were found to be multidrug-resistant (34/178; 19.1%), established through highly concordant laboratory drug susceptibility testing and in silico prediction methods. Some MDR-TB isolates had near identical genomic variation, providing potential evidence of transmission. By placing the Philippine isolates within a phylogeny of global M. tuberculosis (n > 17,000), we established that they are genetically similar to those observed outside the country, including a clade of Manila-like strain-types in Thailand. An analysis of the phylogeny revealed a set of ~200 SNPs that are specific for the Manila strain-type, and a subset can be used within a molecular barcode. Sixty-eight mutations known to be associated with 10 anti-TB drug resistance were identified in the Philippine strains, and all have been observed in other populations. Whilst nine putative streptomycin resistance conferring markers in gid (8) and rrs (1) genes appear to be novel and with functional consequences. Overall, this study provides an important baseline characterisation of M. tuberculosis genetic diversity for the Philippines, and will fill a gap in global datasets and aid the development of a nation-wide database for epidemiological studies and clinical decision making. Further, by establishing a molecular barcode for detecting Manila strains it will assist with the design of diagnostic tools for disease control activities
Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017
Background:
Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods.
Methods:
We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories.
Findings:
From 1950 to 2017, TFRs decreased by 49·4% (95% uncertainty interval [UI] 46·4–52·0). The TFR decreased from 4·7 livebirths (4·5–4·9) to 2·4 livebirths (2·2–2·5), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83·8 million people per year since 1985. The global population increased by 197·2% (193·3–200·8) since 1950, from 2·6 billion (2·5–2·6) to 7·6 billion (7·4–7·9) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2·0%; this rate then remained nearly constant until 1970 and then decreased to 1·1% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2·5% in 1963 to 0·7% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2·7%. The global average age increased from 26·6 years in 1950 to 32·1 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59·9% to 65·3%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1·0 livebirths (95% UI 0·9–1·2) in Cyprus to a high of 7·1 livebirths (6·8–7·4) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0·08 livebirths (0·07–0·09) in South Korea to 2·4 livebirths (2·2–2·6) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0·3 livebirths (0·3–0·4) in Puerto Rico to a high of 3·1 livebirths (3·0–3·2) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2·0% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger.
Interpretation:
Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress
Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017
Background: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49\ub74% (95% uncertainty interval [UI] 46\ub74–52\ub70). The TFR decreased from 4\ub77 livebirths (4\ub75–4\ub79) to 2\ub74 livebirths (2\ub72–2\ub75), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83\ub78 million people per year since 1985. The global population increased by 197\ub72% (193\ub73–200\ub78) since 1950, from 2\ub76 billion (2\ub75–2\ub76) to 7\ub76 billion (7\ub74–7\ub79) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2\ub70%; this rate then remained nearly constant until 1970 and then decreased to 1\ub71% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2\ub75% in 1963 to 0\ub77% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2\ub77%. The global average age increased from 26\ub76 years in 1950 to 32\ub71 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59\ub79% to 65\ub73%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1\ub70 livebirths (95% UI 0\ub79–1\ub72) in Cyprus to a high of 7\ub71 livebirths (6\ub78–7\ub74) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0\ub708 livebirths (0\ub707–0\ub709) in South Korea to 2\ub74 livebirths (2\ub72–2\ub76) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0\ub73 livebirths (0\ub73–0\ub74) in Puerto Rico to a high of 3\ub71 livebirths (3\ub70–3\ub72) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2\ub70% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress. Funding: Bill & Melinda Gates Foundation
Antimicrobial Efficacy and Synergy of Metal Ions against Enterococcus faecium, Klebsiella pneumoniae and Acinetobacter baumannii in Planktonic and Biofilm Phenotypes
The effects of metal ion solutions (silver, copper, platinum, gold and palladium) were determined individually and in combination against Enterococcus faecium, Acinetobacter baumannii and Klebsiella pneumoniae. Platinum, gold and palladium showed the greatest antimicrobial efficacy in zone of inhibition (ZoI) assays. When tested in combinations using ZoI assays, gold/platinum, gold/palladium and platinum/palladium were indicative of synergy. Microbial inhibitory concentration demonstrated platinum and gold against Enterococcus faecium, platinum against Klebsiella pneumoniae and platinum and silver against Acinetobacter baumannii were optimal. Minimal bactericidal concentrations determined the greatest bactericidal activity was again platinum gold and palladium against all three bacteria. Fractional Inhibitory Concentration (FIC) studies demonstrated that the silver/platinum combination against Enterococcus faecium, and silver/copper combination against Acinetobacter baumannii demonstrated antimicrobial synergy. Following crystal violet biofilm assays for single metal ion solutions, antimicrobial efficacies were demonstrated for all the metals against all the bacteria Synergistic assays against biofilms demonstrated gold/palladium, gold/platinumand platinum/palladium resulted in the greatest antimicrobial efficacy. Overall, platinum, palladium and gold metal ion solutions in individual use or combination demonstrated the greatest antimicrobial efficacies against planktonic or biofilm bacteria. This work demonstrates the potential for using a range of metal ions, as biocidal formulations against both planktonic or biofilm bacteria
- …