1,949 research outputs found
Design Evaluation and Alteration of the Dark Harbor 17.5: Case Study of a Modern Replica
While there is still a strong passion and interest for traditional crafts, many of the designs now need to be adapted to comply with the contemporary rules and regulations, and additional modifications are required to meet modern expectations, in areas ranging from comfort to safety; hence the need for modern replicas. In order to ascertain the constraints on modern replicas, a redesign of a Dark Harbor 17.5 will be proposed. First, an initial design evaluation will be performed to assess the characteristic of the original yacht, regarding hydrostatics, hydrodynamics, structural arrangement and stability. Modifications in accordance with regulations and ownerâs requirements will then be implemented to create a modern replica suited to todayâs market. Finally, the new design will be compared to the original one, allowing to evaluate the challenges of design modernization and the impact of contemporary requirements on a traditional design
Seasonal Variation of Thermocline Depth: Consequence on Nutrient Availability in the Ivorian Coastal Zone
Faced with the threat of overfishing in Africa, this study was initiated in the coastal zone of Côte d'Ivoire to understand the nutrients availability as function of variation in the depth of thermocline. Data from the ocean bank, World Ocean Atlas (WOA), were used in the ODV software during the twelve months of 2009 taken at 5.5°W/4.5°N (station coordinates). ODV software has allowed to make seasonal analysis, from vertical profiles and latitudinal analysis from the coast toward the sea through some parameters such as temperature, nitrate, phosphate and oxygen. The depth of thermocline, nitracline, phosphacline and oxycline was determined by the seasonal analysis. To evaluate the enrichment intensity of coast towards the sea, latitudinal analysis was investigated using the section profiles (1°S/5°N coordinates). The main results have shown not only the variation in the depth of the thermocline, but also the variation of nitracline, phosphacline and oxycline at different marine seasons. During the cold season, there was an ascent of the thermocline over the surface of water and a strong enrichment from the coast to the sea especially in August. While in hot season, the thermocline was lower and its stability has favoured the stratification of the water column, which prevents the enrichment of the oxygenated surface layer. Analysis of relationships shows that nutrient elements and oxygen change polynomially with temperature
Improving cereal productivity and farmersâ income using a strategic application of fertilizers in West Africa
In the past two years, ICRISAT, in collaboration with other International Agricultural Research Centres, National Agricultural Research and Extension Systems, has been evaluating and promoting point or hill application of fertilizer along with âWarrantageâ in three West African countries, namely, Burkina Faso, Mali and Niger. The hill application of fertilizers consists of applying small doses of fertilizer in the planting hills of millet and sorghum. The combination of strategic hill application of fertilizer with complementary institutional and market linkages, through an inventory credit system (known as âWarrantageâ) offers a good opportunity to improve crop productivity and farmersâ incomes. Results from the two year on-farm trials showed that, on average, in all the three countries, grain yields of millet and sorghum were greater by 44 to 120% while incomes of farmers increased by 52 to 134% when using hill application of fertilizer than with the earlier recommended fertilizer broadcasting methods and farmersâ practice. Substantial net profits were obtained by farmers using âWarrantageâ. Farmersâ access to credit and inputs was improved substantially through the âWarrantageâ system. The technology has reached up to 12650 farm households in the three countries and efforts are in progress to further scale-up and out the technology to wider geographical area
Percutaneous cementoplasty in multiple myeloma: a valuable adjunct for pain control and ambulation maintenance
Goals of work: Bone pain and functional impairment are major concerns for multiple myeloma (MM) patients. The goal of this study was to better define the role of percutaneous cementoplasty (PC) in improving their quality of life. Materials and methods: This retrospective analysis included 28 consecutive heavily pretreated MM patients managed at our institution between 1996 and 2002. They underwent a total of 34 PC procedures for the treatment of 117 vertebrae and 2 iliac sites and were evaluated at 1month. Main results: Significant pain reduction of >50% was obtained after 83% of the procedures, with a mean visual analogous score decreasing from 7.48/10 to 2.1/10 (pâ<â0.001). It resulted in a complete interruption of opiate analgesic consumption after 59.3% of the procedures, with a mean decrease of 70.4% in the opiate dose. Functional impairment was evaluated with the Eastern Cooperative Oncology Group (ECOG) performance status scale, with mean scores improving from 1.9 to 0.86 after the procedures (pâ=â0.001). There was no major complication. Conclusion: PC is a safe, feasible, and efficient approach for the treatment of bone pain and disability in MM patient
In-situ observations using tagged animals
Marine mammals help gather information on some of the harshest environments on the planet, through the use of miniaturized ocean sensors glued on their fur. Since 2004, hundreds of diving marine animals, mainly Antarctic and Arctic seals, have been fitted with a new generation of Argos tags developed by the Sea Mammal Research Unit of the University of St Andrews in Scotland, UK. These tags investigate the at-sea ecology of these animals while simultaneously collecting valuable oceanographic data. Some of the study species travel thousands of kilometres continuously diving to great depths (up to 2100 m). The resulting data are now freely available to the global scientific community at http://www.meop.net. Despite great progress in their reliability and data accuracy, the current generation of loggers while approaching standard ARGO quality specifications have yet to match them. Yet, improvements are underway; they involve updating the technology, implementing a more systematic phase of calibration and taking benefit of the recently acquired knowledge on the dynamical response of sensors. Together these efforts are rapidly transforming animal tagging into one of the most important sources of oceanographic data in polar regions and in many coastal areas.Publisher PDFNon peer reviewe
Experimental and Simulation Efforts in the Astrobiological Exploration of Exooceans
The icy satellites of Jupiter and Saturn are perhaps the most promising places in the Solar System regarding habitability. However, the potential habitable environments are hidden underneath km-thick ice shells. The discovery of Enceladusâ plume by the Cassini mission has provided vital clues in our understanding of the processes occurring within the interior of exooceans. To interpret these data and to help configure instruments for future missions, controlled laboratory experiments and simulations are needed. This review aims to bring together studies and experimental designs from various scientific fields currently investigating the icy moons, including planetary sciences, chemistry, (micro-)biology, geology, glaciology, etc. This chapter provides an overview of successful in situ, in silico, and in vitro experiments, which explore different regions of interest on icy moons, i.e. a potential plume, surface, icy shell, water and brines, hydrothermal vents, and the rocky core
Overdominant effect of a CHRNA4 polymorphism on cingulo-opercular network activity and cognitive control
The nicotinic system plays an important role in cognitive control, and is implicated in several neuropsychiatric conditions. Yet, the contributions of genetic variability in this system to individuals' cognitive control abilities are poorly understood, and the brain processes that mediate such genetic contributions remain largely unidentified. In this first large-scale neuroimaging genetics study of the human nicotinic receptor system (two cohorts, males and females, fMRI total N=1586, behavioral total N=3650), we investigated a common polymorphism of the high-affinity nicotinic receptor ι4β2 (rs1044396 on the CHRNA4 gene) previously implicated in behavioral and nicotine-related studies (albeit with inconsistent major/minor allele impacts). Based on our prior neuroimaging findings, we expected this polymorphism to impact neural activity in the cingulo-opercular network involved in core cognitive control processes including maintenance of alertness. Consistent across the cohorts, all cortical areas of the cingulo-opercular network showed higher activity in heterozygotes compared to both types of homozygotes during cognitive engagement. This inverted U-shaped relation reflects an overdominant effect, i.e. allelic interaction (cumulative evidence p=1.33*10-5). Furthermore, heterozygotes performed more accurately in behavioral tasks that primarily depend on sustained alertness. No effects were observed for haplotypes of the surrounding CHRNA4 region, supporting a true overdominant effect at rs1044396. As a possible mechanism, we observed that this polymorphism is an expression quantitative trait locus (eQTL) modulating CHRNA4 expression levels. This is the first report of overdominance in the nicotinic system. These findings connect CHRNA4genotype, cingulo-opercular network activation and sustained alertness, providing insights into how genetics shapes individuals' cognitive control abilities
Effects of antibiotic resistance, drug target attainment, bacterial pathogenicity and virulence, and antibiotic access and affordability on outcomes in neonatal sepsis: an international microbiology and drug evaluation prospective substudy (BARNARDS).
BACKGROUND: Sepsis is a major contributor to neonatal mortality, particularly in low-income and middle-income countries (LMICs). WHO advocates ampicillin-gentamicin as first-line therapy for the management of neonatal sepsis. In the BARNARDS observational cohort study of neonatal sepsis and antimicrobial resistance in LMICs, common sepsis pathogens were characterised via whole genome sequencing (WGS) and antimicrobial resistance profiles. In this substudy of BARNARDS, we aimed to assess the use and efficacy of empirical antibiotic therapies commonly used in LMICs for neonatal sepsis. METHODS: In BARNARDS, consenting mother-neonates aged 0-60 days dyads were enrolled on delivery or neonatal presentation with suspected sepsis at 12 BARNARDS clinical sites in Bangladesh, Ethiopia, India, Pakistan, Nigeria, Rwanda, and South Africa. Stillborn babies were excluded from the study. Blood samples were collected from neonates presenting with clinical signs of sepsis, and WGS and minimum inhibitory concentrations for antibiotic treatment were determined for bacterial isolates from culture-confirmed sepsis. Neonatal outcome data were collected following enrolment until 60 days of life. Antibiotic usage and neonatal outcome data were assessed. Survival analyses were adjusted to take into account potential clinical confounding variables related to the birth and pathogen. Additionally, resistance profiles, pharmacokinetic-pharmacodynamic probability of target attainment, and frequency of resistance (ie, resistance defined by in-vitro growth of isolates when challenged by antibiotics) were assessed. Questionnaires on health structures and antibiotic costs evaluated accessibility and affordability. FINDINGS: Between Nov 12, 2015, and Feb 1, 2018, 36â285 neonates were enrolled into the main BARNARDS study, of whom 9874 had clinically diagnosed sepsis and 5749 had available antibiotic data. The four most commonly prescribed antibiotic combinations given to 4451 neonates (77¡42%) of 5749 were ampicillin-gentamicin, ceftazidime-amikacin, piperacillin-tazobactam-amikacin, and amoxicillin clavulanate-amikacin. This dataset assessed 476 prescriptions for 442 neonates treated with one of these antibiotic combinations with WGS data (all BARNARDS countries were represented in this subset except India). Multiple pathogens were isolated, totalling 457 isolates. Reported mortality was lower for neonates treated with ceftazidime-amikacin than for neonates treated with ampicillin-gentamicin (hazard ratio [adjusted for clinical variables considered potential confounders to outcomes] 0¡32, 95% CI 0¡14-0¡72; p=0¡0060). Of 390 Gram-negative isolates, 379 (97¡2%) were resistant to ampicillin and 274 (70¡3%) were resistant to gentamicin. Susceptibility of Gram-negative isolates to at least one antibiotic in a treatment combination was noted in 111 (28¡5%) to ampicillin-gentamicin; 286 (73¡3%) to amoxicillin clavulanate-amikacin; 301 (77¡2%) to ceftazidime-amikacin; and 312 (80¡0%) to piperacillin-tazobactam-amikacin. A probability of target attainment of 80% or more was noted in 26 neonates (33¡7% [SD 0¡59]) of 78 with ampicillin-gentamicin; 15 (68¡0% [3¡84]) of 27 with amoxicillin clavulanate-amikacin; 93 (92¡7% [0¡24]) of 109 with ceftazidime-amikacin; and 70 (85¡3% [0¡47]) of 76 with piperacillin-tazobactam-amikacin. However, antibiotic and country effects could not be distinguished. Frequency of resistance was recorded most frequently with fosfomycin (in 78 isolates [68¡4%] of 114), followed by colistin (55 isolates [57¡3%] of 96), and gentamicin (62 isolates [53¡0%] of 117). Sites in six of the seven countries (excluding South Africa) stated that the cost of antibiotics would influence treatment of neonatal sepsis. INTERPRETATION: Our data raise questions about the empirical use of combined ampicillin-gentamicin for neonatal sepsis in LMICs because of its high resistance and high rates of frequency of resistance and low probability of target attainment. Accessibility and affordability need to be considered when advocating antibiotic treatments with variance in economic health structures across LMICs. FUNDING: The Bill & Melinda Gates Foundation
- âŚ