154 research outputs found

    Organization of the Petroleum Exporting Countries (OPEC) and Opportunities for Sustainable Development

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    OPEC is in the business of natural resources which inherently connects them to the concept of sustainable development. The main focus of this research is to answer the following question: Does OPEC have the power to implement measures consistent with the concept of sustainable development? During the course of this research, the paper Sustainable Development and OPEC, by Herman E. Daly, was uncovered. Daly proposes a sink tax to be implemented by OPEC. This would act as a global fiduciary which would, in theory, bring the consumption level of oil down to a more sustainable level by raising the price and lowering the demand. The research in this paper finds that Dalys speculative idea, while interesting, is unrealistic; the idea is not feasible given OPECs stated goals. In addition, there are ethical considerations concerning a conflict of interest on a global and local scale

    ACES RED Experiment #1 Environmental Test Results for Industrial Grade, Non-traditional, and Other Components Lacking Flight Heritage

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    Results of the thermal vacuum chamber (TVAC) testing and vibrational testing of the ACES RED Experiment #1 are presented. Performance of commercial-off-the-shelf components such as the Avnet PicoZed, the Xiphos Q7, the MAI-400, and a NovaTel GNSS during TVAC testing are provided and analyzed. To our knowledge, this is the first orbital flight of this version of the GNSS, this version of the MAI-400, and the PicoZed. The experiment utilizes a novel structural concept for ease of electronics assembly and disassembly. The health monitoring system measures temperatures, vibration, voltages, and currents for situational awareness of each of these component\u27s relative performance. An assessment and progression of the technology readiness level of the hardware is also presented

    Impacto socioeconómico y productivo de los micronegocios de la región andina (Colombia) en tiempos de pandemia por covid-19

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    With the emergence of the COVID-19 pandemic, many of the establishments selling products and providing services were affected by the temporary closures decreed in order to control the spread of the virus, causing in many cases the reduction of income, loss of labor force, partial or definitive closure. The objective of this article was to determine the impact of the pandemic on micro-businesses in the Andean Region. For this purpose, a social, economic and productive characterization was applied to 2692 micro-businesses randomly selected in different cities of the Andean Region, in order to understand how the COVID-19 pandemic impacted these micro-businesses. The methodology used was IBM's CRISP-DM. It is concluded that the micro-businesses are mostly managed by women, most of them with basic secondary education, and it was also evidenced that during the pandemic, sales were reduced and jobs were lost.Con la aparición de la pandemia del COVID-19, muchos de los establecimientos de venta de productos y prestación de servicios se vieron afectados por los cierres temporales decretados a fin de controlar la propagación del virus, ocasionando en muchos casos la reducción de los ingresos, perdida de la fuerza laboral, el cierre parcial o definitivo. Este artículo tuvo como objetivo conocer el impacto de la pandemia en los micronegocios de la Región Andina. Para esto se aplicó una caracterización social, económica y productiva a 2692 micronegocios seleccionados de forma aleatoria en las diferentes ciudades de la Región Andina, a fin poder comprender como la pandemia del COVID-19 impacto estos micronegocios. La metodología utilizada fue la CRISP-DM de IBM. Se concluye que los micronegocios son mayormente administrados por mujeres, en su mayoría con formación básica secundaria, así mismo se evidenció que durante la pandemia redujeron las ventas y se perdieron puestos de trabajo

    Evidence for lateral transfer of genes encoding ferredoxins, nitroreductases, NADH oxidase, and alcohol dehydrogenase 3 from anaerobic prokaryotes to Giardia lamblia and Entamoeba histolytica

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    Author Posting. © American Society for Microbiology, 2002. This article is posted here by permission of American Society for Microbiology for personal use, not for redistribution. The definitive version was published in Eukaryotic Cell 1 (2002): 181-190, doi:10.1128/EC.1.2.181-190.2002.Giardia lamblia and Entamoeba histolytica are amitochondriate, microaerophilic protists which use fermentation enzymes like those of bacteria to survive anaerobic conditions within the intestinal lumen. Genes encoding fermentation enzymes and related electron transport peptides (e.g., ferredoxins) in giardia organisms and amebae are hypothesized to be derived from either an ancient anaerobic eukaryote (amitochondriate fossil hypothesis), a mitochondrial endosymbiont (hydrogen hypothesis), or anaerobic bacteria (lateral transfer hypothesis). The goals here were to complete the molecular characterization of giardial and amebic fermentation enzymes and to determine the origins of the genes encoding them, when possible. A putative giardia [2Fe-2S]ferredoxin which had a hypothetical organelle-targeting sequence at its N terminus showed similarity to mitochondrial ferredoxins and the hydrogenosomal ferredoxin of Trichomonas vaginalis (another luminal protist). However, phylogenetic trees were star shaped, with weak bootstrap support, so we were unable to confirm or rule out the endosymbiotic origin of the giardia [2Fe-2S]ferredoxin gene. Putative giardial and amebic 6-kDa ferredoxins, ferredoxin-nitroreductase fusion proteins, and oxygen-insensitive nitroreductases each tentatively supported the lateral transfer hypothesis. Although there were not enough sequences to perform meaningful phylogenetic analyses, the unique common occurrence of these peptides and enzymes in giardia organisms, amebae, and the few anaerobic prokaryotes suggests the possibility of lateral transfer. In contrast, there was more robust phylogenetic evidence for the lateral transfer of G. lamblia genes encoding an NADH oxidase from a gram-positive coccus and a microbial group 3 alcohol dehydrogenase from thermoanaerobic prokaryotes. In further support of lateral transfer, the G. lamblia NADH oxidase and adh3 genes appeared to have an evolutionary history distinct from those of E. histolytica.This work was supported by NIH grants (AI33492 to J.S., AI43273 to M.L.S., and AI46516 to B.J.L.). Additional support was provided by the G. Unger Vetlesen Foundation and LI-COR Biotechnology

    Single and Synergistic Effects of Cannabidiol and Δ-9-Tetrahydrocannabinol on Zebrafish Models of Neuro-Hyperactivity

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    In this study, we aimed to investigate the effect of the two main active cannabinoids extracted from cannabis: Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) on two distinct behavioral models of induced neuro-hyperactivity. We have taken advantage of two previously developed zebrafish models of neuro-hyperactivity: a chemically induced pentylenetetrazole model and a genetic model caused by loss-of-function mutations in the GABA receptor subunit alpha 1 (GABRA1−/−). Both CBD and THC have a significant effect on the behavioral changes induced by both models. Importantly, we have also shown that when applied together at different ratios of THC to CBD (1:1, 1:5, and 1:10), there was a synergistic effect at a ratio of 1:1. This was particularly important for the genetically induced neuro-hyperactivity as it brought the concentrations of THC and CBD required to oppose the induced behavioral changes to levels that had much less of an effect on baseline larval behavior. The results of this study help to validate the ability of THC and CBD to oppose neuro-hyperactivity linked to seizure modalities. Additionally, it appears that individually, each cannabinoid may be more effective against the chemically induced model than against the GABRA1−/− transgenic model. However, when applied together, the concentration of each compound required to oppose the GABRA1−/− light-induced activity was lowered. This is of particular interest since the use of cannabinoids as therapeutics can be dampened by their side-effect profile. Reducing the level of each cannabinoid required may help to prevent off target effects that lead to side effects. Additionally, this study provides a validation of the complimentary nature of the two zebrafish models and sets a platform for future work with cannabinoids, particularly in the context of neuro-hyperactivity disorders such as epilepsy

    Postnatal dexamethasone, respiratory and neurodevelopmental outcomes at two years in babies born extremely preterm.

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    IMPORTANCE: Postnatal dexamethasone is associated with reduction in bronchopulmonary dysplasia. There remains, however, concern that its short-term benefits are accompanied by long-term adverse effects e.g. poorer neurodevelopmental outcomes. OBJECTIVE: Our aim was to determine the effects of administration of postnatal dexamethasone on respiratory and neurodevelopmental outcome at two years of age after adjusting for neonatal and infant risk factors. MATERIALS AND METHODS: The study included 412 infants born at 23-28 weeks of gestation, 29% had received postnatal dexamethasone. Two outcomes were examined, respiratory hospital admissions in the past 12 months and neurodevelopmental impairment. Logistic regression, adjusted for sex, birthweight z-score, gestation, maternal smoking, oxygen dependency at 36 weeks, airleak, patent ductus arteriosus, pulmonary haemorrhage, major ultrasound abnormality, mode of ventilation and age at assessment, was undertaken. RESULTS: After adjustment, postnatal dexamethasone was associated with significantly increased proportions of both respiratory hospital readmission: (0.35 vs 0.15, difference = 0.20; 95% CI: 0.08, 0.31) and neurodevelopmental impairment (0.59 vs 0.45, difference = 0.14; 95% CI: 0.02, 0.26). CONCLUSIONS: Postnatal dexamethasone use in extremely preterm infants is associated with increased risks of respiratory hospital admissions and neurodevelopmental impairment. These associations were not explained by excess neonatal morbidities

    New ophthalmosaurid ichthyosaurs from the European lower cretaceous demonstrate extensive ichthyosaur survival across the Jurassic–Cretaceous boundary

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    Background Ichthyosauria is a diverse clade of marine amniotes that spanned most of the Mesozoic. Until recently, most authors interpreted the fossil record as showing that three major extinction events affected this group during its history: one during the latest Triassic, one at the Jurassic–Cretaceous boundary (JCB), and one (resulting in total extinction) at the Cenomanian-Turonian boundary. The JCB was believed to eradicate most of the peculiar morphotypes found in the Late Jurassic, in favor of apparently less specialized forms in the Cretaceous. However, the record of ichthyosaurs from the Berriasian–Barremian interval is extremely limited, and the effects of the end-Jurassic extinction event on ichthyosaurs remains poorly understood. Methodology/Principal Findings Based on new material from the Hauterivian of England and Germany and on abundant material from the Cambridge Greensand Formation, we name a new ophthalmosaurid, Acamptonectes densus gen. et sp. nov. This taxon shares numerous features with Ophthalmosaurus, a genus now restricted to the Callovian–Berriasian interval. Our phylogenetic analysis indicates that Ophthalmosauridae diverged early in its history into two markedly distinct clades, Ophthalmosaurinae and Platypterygiinae, both of which cross the JCB and persist to the late Albian at least. To evaluate the effect of the JCB extinction event on ichthyosaurs, we calculated cladogenesis, extinction, and survival rates for each stage of the Oxfordian–Barremian interval, under different scenarios. The extinction rate during the JCB never surpasses the background extinction rate for the Oxfordian–Barremian interval and the JCB records one of the highest survival rates of the interval. Conclusions/Significance There is currently no evidence that ichthyosaurs were affected by the JCB extinction event, in contrast to many other marine groups. Ophthalmosaurid ichthyosaurs remained diverse from their rapid radiation in the Middle Jurassic to their total extinction at the beginning of the Late Cretaceous

    Female patients with low systemic BMD are prone to bone loss in Gruen zone 7 after cementless total hip arthroplasty: A 2-year DXA follow-up of 39 patients

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    Background and purpose Factors that lead to periprosthetic bone loss following total hip arthroplasty (THA) may not only depend on biomechanical implant-related factors, but also on various patient-related factors. We investigated the association between early changes in periprosthetic bone mineral density (BMD) and patient-related factors
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