16 research outputs found
Stratification of malaria incidence in Papua New Guinea (2011-2019): contribution towards a sub-national control policy
Malaria risk in Papua New Guinea (PNG) is highly heterogeneous, between and within geographical regions, which is operationally challenging for control. To enhance targeting of malaria interventions in PNG, we investigated risk factors and stratified malaria incidence at the level of health facility catchment areas. Catchment areas and populations of 808 health facilities were delineated using a travel-time accessibility approach and linked to reported malaria cases (2011-2019). Zonal statistics tools were used to calculate average altitude and air temperature in catchment areas before they were spatially joined with incidence rates. In addition, empirical Bayesian kriging (EBK) was employed to interpolate incidence risk strata across PNG. Malaria annual incidence rates are, on average, 186.3 per 1000 population in catchment areas up to 600 m, dropped to 98.8 at (800-1400) m, and to 24.1 cases above 1400 m altitude. In areas above the two altitudinal thresholds 600m and 1400m, the average annual temperature drops below 22°C and 17°C, respectively. EBK models show very low- to low-risk strata ( 200 per 1000) strata are modelled mainly in Momase and Islands Regions. Besides, strata with moderate risk (100-200) predominate throughout the coastal areas. While 35.7% of the PNG population (estimated 3.33 million in 2019) lives in places at high or moderate risk of malaria, 52.2% (estimated 4.88 million) resides in very low-risk areas. In five provinces, relatively large proportions of populations (> 50%) inhabit high-risk areas: New Ireland, East and West New Britain, Sandaun and Milne Bay. Incidence maps show a contrast in malaria risk between coastal and inland areas influenced by altitude. However, the risk is highly variable in low-lying areas. Malaria interventions should be guided by sub-national risk levels in PNG
Morocco’s sustainable energy transition and the role of financing costs: a participatory electricity system modeling approach
Background
Morocco is facing major challenges in terms of its future energy supply and demand. Specifically, the country is confronted with rising electricity demand, which in turn will lead to higher fossil fuel import dependency and carbon emissions. Recognizing these challenges, Morocco has set ambitious targets for the deployment of renewable energy sources for electricity generation (RES-E). The realization of these targets will lead to a fundamental transition of the Moroccan electricity sector and requires substantial public and private investment. However, different risks constitute barriers for private RES-E investments and lead to high financing costs, which may eventually discourage capital-intensive RES-E projects.
Methodology
While the existing literature has mainly focused on assessing the impact of financing costs on the economic competitiveness of individual technologies, the aim of this research is to assess the techno-economic feasibility of different electricity generation portfolios. To recognize the social dimension of the sustainable energy system transition, the electricity scenarios for Morocco have been jointly developed with stakeholders in a scenario building workshop in Rabat, employing a downscaled version of the open source electricity market model renpassG!S, augmented by a weighted average cost of capital (WACC) module.
Results
In the stakeholder workshop, four different electricity scenarios for Morocco were co-developed. Each of these scenarios describes a consensual and technologically feasible future development path for the Moroccan energy system up to 2050, and comprises conventional fossil fuel-based technologies, as well as RES-E technologies in varying shares. Employing the downscaled renpassG!S model, we find that total system costs, as well as average levelized costs of electricity (LCOE) can be reduced substantially with low-cost financing.
Conclusions
Our results indicate that de-risking RES-E investments can lead to cost competitiveness of a 100% RES-E-based electricity system with mixed-technology scenarios at marked financing costs. Therefore, we identify specific de-risking recommendations for Moroccan energy policymaking. In addition, we argue that participatory scenario modeling enables a better understanding of the risk perceptions of stakeholders, and can eventually contribute to increasing the political feasibility of sustainable energy transition pathways
Plasminogen activator inhibitor-2 and impaired fibrinolysis in pregnancy and sickle cell anemia.
This is the first study that aimed to determine antigen levels in plasma and genotypes of PAI-2 in pregnant and non-pregnant homozygous sickle cell anemia (SCA) patients. The study subjects were all Bahraini females in the reproductive age group. The study population included 31 pregnant homozygous SS (SCA) patients. Three control groups were also studied to evaluate the effect of pregnancy and SCA on PAI-2 levels and fibrinolysis: (1) 31 healthy non-pregnant volunteers; (2) 31 cases of normal pregnancy; and (3) 20 non-pregnant SCA patients. Pregnancies were screened in the second (TM2) and third (TM3) trimesters. Global coagulation, fibrinolysis rate (euglobulin clot lysis time, ECLT), PAI-2 antigen (ELISA), and PAI-2 Ser(413)/Cys polymorphism (restriction fragment length polymorphism analysis) were determined. Feto-maternal complications were documented in both pregnancy groups. PAI-2 antigen levels were undetectable in the non-pregnant groups, but was quantifiable in both pregnant groups. Impaired fibrinolysis rate and rising PAI-2 levels with progression of pregnancy were observed in both healthy and SCA subjects. These changes were more prominent in SCA, although the rise in ECLT was less steep and PAI-2 antigen levels were not significantly different compared to normal pregnancy in the third trimester. No correlation was observed between PAI-2 genotypes and plasma antigen levels. Also, no significant difference in feto-maternal complications was found in normal (n = 25) versus SCA pregnant patients (n = 30). These observations suggest that with progression of pregnancy, increasing PAI-2 levels contribute to the hypercoagulable state, particularly in SCA patients. [Abstract copyright: © 2023. The Author(s).
Recommended from our members
Integrated Management of Leafy Spurge-Infested Rangeland
Leafy spurge is an invasive Eurasian weed on pastures and rangeland in North America where it reduces grass forage production. Our objective was to determine the effects of multispecies grazing combined with Aphthona flea beetles on leafy spurge-infested rangeland. On two western North Dakota sites divided into four 25- to 79-ha pastures, two grazing duration treatments were applied: season-long with 7 to 10 cow pairs and 20 to 25 sheep from late May through mid-September, and rotation with 18 to 21 cow calf pairs and 45 to 60 sheep for 3 weeks twice per year. Grazing treatments started in 1998 and continued through 2002. Aphthona spp. were released beginning 1991 and were widespread in both pastures by 1998. Four grazing enclosures were randomly located in each pasture in the spring of 1998. Cover of leafy spurge, grass, and forbs, as well as density of vegetative and flowering leafy spurge stems were measured in July 1998 through 2002. Aphthona densities were counted July 1999 through 2002. Grazing initially increased leafy spurge vegetative stem density, but grazing decreased vegetative stem density from 104 in 1999 to 20 stems m-2 in 2002. Season-long grazing reduced vegetative stem density by over 30 stems m-2 compared to rotation grazing. Leafy spurge flowering stems decreased from 80 stems m-2 to 4 stems m-2 in 2002 in all treatments. The decrease was more rapid when grazing was combined with Aphthona. Initially, Aphthona densities were greater in the grazed areas than the exclosures, but by 2002 more Aphthona were found in the exclosures than the grazed areas. Grazing reduced grass cover and increased forb cover. Results suggest combining multispecies grazing and Aphthona when restoring spurge-infested grasslands produces a synergistic effect.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 2020Legacy DOIs that must be preserved: 10.2458/azu_jrm_v59i5_jacob
Уменьшение сопротивления трению самолета путем микровыдува через пористый участок поверхности
На прикладі крила літака Ан-124 було досліджено переваги та особливості впливу на опір літака мікровидуву повітря через пористу ділянку обтічної поверхні. Проведено параметричний аналіз впливу швидкості видуву, розташування та довжини ділянки видуву на крилі, визначено умови та співвідношення параметрів, при яких забезпечується найкращий ефект за умови збереження безвідривного обтікання.The last 45 years have been characterized by escalation of the problem of energy saving and, accordingly, the search and implementation of various resource-saving technologies in various spheres of human activity and, first of all, in the energy and transport sectors. In particular, this problem became urgent for aviation transport and it is not difficult to assume that in the future this process will only increase. Gradual optimization of power plants and aerodynamic design of aircraft in the process of steady improvement of aircraft characteristics and development of the appropriate technological base led to the fact that the traditional methods of fuel consumption reducing are almost exhausted.
Aircraft drag consists of several components: inductive, wave, pressure and frictional. The first three components are studied well enough and methods of their reduction are widely used on airplanes. Nevertheless, friction drag can be effectively reduced by boundary layer control methods. Among them there are wellknown and deeply studied ones but for some reasons they were not applied earlier because of the inability or ineffectiveness of their technological implementation. There are methods that are still awaiting for their detailed studies.
Determining the optimal, in terms of the frictional drag reduction and the technological considerations, placement and length of the blowing section (or several sections) along the airplane wing chord are practically unexplored. This set of problems is the subject of authors consideration and research presented in this article.
On the basis of An-124 aircraft wing the advantages and phenomena of the influence of micro-blowing through the porous section of streamlined surface have been investigated. Parametric analysis of the effect of blowing speed, location and length of the blowing section along the wing has been performed and the conditions and ratios of the parameters, which provide the best effect for the case of maintaining flow without separation, have been determined.На примере крыла самолета Ан-124 были исследованы преимущества и особенности влияния на сопротивление самолета микровыдува воздуха через пористый участок обтекаемой поверхности. Проведен параметрический анализ влияния скорости выдува, расположения и длины участка выдува на крыле, определены условия и соотношения параметров, при которых обеспечивается наилучший эффект при сохранении безотрывного обтекания