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Cost assessment of clean generation incentives in Mexico for utility scale solar photovoltaic projects
Mexico recently opened the electric generation sector to competition. In addition, regulations to reach clean generation goals were implemented. These regulations include Clean Energy Certificates (CELs) obligations (similar to the Renewable Portfolio Standards in the United States), and the obligation of electricity suppliers to go into long term contracts with generators to guarantee the required electric energy and CELs supply. These contracts are procured through an auction mechanism. The purpose of this research is to i) estimate the cost of reaching the goals through the implemented policy, and ii) evaluate if the projects could be economically feasible by selling electricity in the short term market, without the incentives. This research looked at three different utility scale solar photovoltaic projects that will operate under long term contracts for the provision of electric energy and CELs. The revenues of the projects under the contract terms were modeled and contrasted with projected Locational Marginal Prices (LMPs). In addition, a discounted cash flow analysis was done for the three projects, both under long term contract conditions and short term market conditions.
Two projects were found to be financially feasible under short term market conditions. For these projects, the LMP was between 4.03 USD/MWh higher than the long term contract price. One project was not feasible under short term market conditions. For this project to be feasible in the short term market, the LMPs needed to be over 1.29 USD/MWh higher than the projected LMPs. These results show that the policy implemented is efficient, provides benefits to customers, and in some cases to investors. In the cases where the projects were feasible without the incentive, they would have sold their energy for a higher price without the long term contract mechanism. In addition, the project that was not financially feasible under short term market conditions would have needed a higher premium over the LMP price, than the premium achieved through the long term contract.Energy and Earth Resource
Characterization of Sex-Based Dna Methylation Signatures in the Airways During Early Life.
Human respiratory conditions are largely influenced by the individual\u27s sex resulting in overall higher risk for males. Sex-based respiratory differences are present at birth suggesting a strong genetic component. Our objective was to characterize early life sex-based genomic signatures determined by variable X-chromosome methylation in the airways. We compared male versus female genome-wide DNA methylation in nasal airway samples from newborns and infants aged 1-6 months (N = 12). We analyzed methylation signals across CpG sites mapped to each X-linked gene using an unsupervised classifier (principal components) followed by an internal evaluation and an exhaustive cross-validation. Results were validated in an independent population of children (N = 72) following the same algorithm. X-linked genes with significant sex-based differential methylation in the nasal airway of infants represented only about 50% of the unique protein coding transcripts. X-linked genes without significant sex-based differential methylation included genes with evidence of escaping X-inactivation and female-biased airway expression. These genes showed similar methylation patterns in males and females suggesting unbalanced X-chromosome dosage. In conclusion, we identified that the human airways have already sex-based DNA methylation signatures at birth. These early airway epigenomic marks may determine sex-based respiratory phenotypes and overall predisposition to develop respiratory disorders later in life
Spatio-temporal expression patterns of Arabidopsis thaliana and Medicago truncatula defensin-like genes
Plant genomes contain several hundred defensin-like (DEFL) genes that encode short cysteine-rich proteins resembling defensins, which are well known antimicrobial polypeptides. Little is known about the expression patterns or functions of many DEFLs because most were discovered recently and hence are not well represented on standard microarrays. We designed a custom Affymetrix chip consisting of probe sets for 317 and 684 DEFLs from Arabidopsis thaliana and Medicago truncatula, respectively for cataloging DEFL expression in a variety of plant organs at different developmental stages and during symbiotic and pathogenic associations. The microarray analysis provided evidence for the transcription of 71% and 90% of the DEFLs identified in Arabidopsis and Medicago, respectively, including many of the recently annotated DEFL genes that previously lacked expression information. Both model plants contain a subset of DEFLs specifically expressed in seeds or fruits. A few DEFLs, including some plant defensins, were significantly up-regulated in Arabidopsis leaves inoculated with Alternaria brassicicola or Pseudomonas syringae pathogens. Among these, some were dependent on jasmonic acid signaling or were associated with specific types of immune responses. There were notable differences in DEFL gene expression patterns between Arabidopsis and Medicago, as the majority of Arabidopsis DEFLs were expressed in inflorescences, while only a few exhibited root-enhanced expression. By contrast, Medicago DEFLs were most prominently expressed in nitrogen-fixing root nodules. Thus, our data document salient differences in DEFL temporal and spatial expression between Arabidopsis and Medicago, suggesting distinct signaling routes and distinct roles for these proteins in the two plant species
Trends in the incidence of AIDS-defining and non-AIDS-defining cancers in people living with AIDS: a population-based study from Sao Paulo, Brazil
People living with AIDS are at increased risk of developing certain cancers. Since the introduction of the highly active antiretroviral therapy (HAART), the incidence of AIDS-defining cancers (ADCs) has decreased in high-income countries. The objective of this study was to analyse trends in ADCs and non-AIDS-defining cancers (NADCs) in HIV-positive people with a diagnosis of AIDS, in comparison to the general population, in Sao Paulo, Brazil. A probabilistic record linkage between the 'Population-based Cancer Registry of Sao Paulo' and the AIDS notification database (SINAN) was conducted. Cancer trends were assessed by annual per cent change (APC). In people with AIDS, 2074 cancers were diagnosed. Among men with AIDS, the most frequent cancer was Kaposi's sarcoma (469;31.1%), followed by non-Hodgkin lymphoma (NHL;304;20.1%). A decline was seen for ADCs (APC = -14.1%). All NADCs have increased (APC = -7.4%/year) significantly since the mid-2000s driven by the significant upward trends of anal (APC = -24.6%/year) and lung cancers (APC = -15.9%/year). In contrast, in men from the general population, decreasing trends were observed for these cancers. For women with AIDS, the most frequent cancer was cervical (114;20.2%), followed by NHL (96;17.0%). Significant declining trends were seen for both ADCs (APC = -15.6%/ year) and all NADCs (APC = -15.8%/ year), a comparable pattern to that found for the general female population. Trends in cancers among people with AIDS in Sao Paulo showed similar patterns to those found in developed countries. Although ADCs have significantly decreased, probably due to the introduction of HAART, NADCs in men have shown an opposite upward trend
Oximetry signal processing identifies REM sleep-related vulnerability trait in asthmatic children
Rationale. The sleep-related factors that modulate the nocturnal worsening of asthma in children are poorly understood. This study addressed the hypothesis that asthmatic children have a REM sleep-related vulnerability trait that is independent of OSA.
Methods. We conducted a retrospective cross-sectional analysis of pulse-oximetry signals obtained during REM and NREM sleep in control and asthmatic children (n=134). Asthma classification was based on preestablished clinical criteria. Multivariate linear regression model was built to control for potential confounders (significance level p ≤ 0.05).
Results. Our data demonstrated that (1) baseline nocturnal respiratory parameters were not significantly different in asthmatic versus control children, (2) the maximal % of SaO2 desaturation during REM, but not during NREM, was significantly higher in asthmatic children, and (3) multivariate analysis revealed that the association between asthma and REM-related maximal % SaO2 desaturation was independent of demographic variables.
Conclusion. These results demonstrate that children with asthma have a REM-related vulnerability trait that impacts oxygenation independently of OSA. Further research is needed to delineate the REM sleep neurobiological mechanisms that modulate the phenotypical expression of nocturnal asthma in children
Jasmonate promotes auxin-induced adventitious rooting in dark-grown Arabidopsis thaliana seedlings and stem thin cell layers by a cross-talk with ethylene signalling and a modulation of xylogenesis
Background: Adventitious roots (ARs) are often necessary for plant survival, and essential for successful micropropagation. In Arabidopsis thaliana dark-grown seedlings AR-formation occurs from the hypocotyl and is enhanced by application of indole-3-butyric acid (IBA) combined with kinetin (Kin). The same IBA + Kin-treatment induces AR-formation in thin cell layers (TCLs). Auxin is the main inducer of AR-formation and xylogenesis in numerous species and experimental systems. Xylogenesis is competitive to AR-formation in Arabidopsis hypocotyls and TCLs. Jasmonates (JAs) negatively affect AR-formation in de-etiolated Arabidopsis seedlings, but positively affect both AR-formation and xylogenesis in tobacco dark-grown IBA + Kin TCLs. In Arabidopsis the interplay between JAs and auxin in AR-formation vs xylogenesis needs investigation. In de-etiolated Arabidopsis seedlings, the Auxin Response Factors ARF6 and ARF8 positively regulate AR-formation and ARF17 negatively affects the process, but their role in xylogenesis is unknown. The cross-talk between auxin and ethylene (ET) is also important for AR-formation and xylogenesis, occurring through EIN3/EIL1 signalling pathway. EIN3/EIL1 is the direct link for JA and ET-signalling. The research investigated JA role on AR-formation and xylogenesis in Arabidopsis dark-grown seedlings and TCLs, and the relationship with ET and auxin. The JA-donor methyl-jasmonate (MeJA), and/or the ET precursor 1-aminocyclopropane-1-carboxylic acid were applied, and the response of mutants in JA-synthesis and -signalling, and ET-signalling investigated. Endogenous levels of auxin, JA and JA-related compounds, and ARF6, ARF8 and ARF17 expression were monitored. Results: MeJA, at 0.01 μM, enhances AR-formation, when combined with IBA + Kin, and the response of the early-JA-biosynthesis mutant dde2–2 and the JA-signalling mutant coi1–16 confirmed this result. JA levels early change during TCL-culture, and JA/JA-Ile is immunolocalized in AR-tips and xylogenic cells. The high AR-response of the late JA-biosynthesis mutant opr3 suggests a positive action also of 12-oxophytodienoic acid on AR-formation. The crosstalk between JA and ET-signalling by EIN3/EIL1 is critical for AR-formation, and involves a competitive modulation of xylogenesis. Xylogenesis is enhanced by a MeJA concentration repressing AR-formation, and is positively related to ARF17 expression. Conclusions: The JA concentration-dependent role on AR-formation and xylogenesis, and the interaction with ET opens the way to applications in the micropropagation of recalcitrant species
Characterization of cytomegalovirus lung infection in non-HIV infected children
Cytomegalovirus (CMV) is a prevalent pathogen in the immunocompromised host and invasive pneumonia is a feared complication of the virus in this population. In this pediatric case series we characterized CMV lung infection in 15 non-HIV infected children (median age 3 years; IQR 0.2–4.9 years), using current molecular and imaging diagnostic modalities, in combination with respiratory signs and symptoms. The most prominent clinical and laboratory findings included cough (100%), hypoxemia (100%), diffuse adventitious breath sounds (100%) and increased respiratory effort (93%). All patients had abnormal lung images characterized by ground glass opacity/consolidation in 80% of cases. CMV was detected in the lung either by CMV PCR in bronchoalveolar lavage (82% detection rate) or histology/immunohistochemistry in lung biopsy (100% detection rate). CMV caused respiratory failure in 47% of children infected and the overall mortality rate was 13.3%. Conclusion: CMV pneumonia is a potential lethal disease in non-HIV infected children that requires a high-index of suspicion. Common clinical and radiological patterns such as hypoxemia, diffuse adventitious lung sounds and ground-glass pulmonary opacities may allow early identification of CMV lung infection in the pediatric population, which may lead to prompt initiation of antiviral therapy and better clinical outcomes
Prenatal gunshot wound, a rare cause of maternal and fetus trauma, a case report
Background: Gunshot wounds in pregnant women, although rare, represent an important cause of fetal and maternal mortality. Understanding the mechanism of injury is essential to identify the possible injuries and to adequately manage the complexity of these emergency scenarios.
Case presentation: We present a case of a 27-year-old woman and her 37 week fetus who were the victims of a gunshot wound. The trajectory of the bullet injured not only the mother but also the developing fetus. An emergency c-section was performed and the bullet was removed from the infant's abdomen. The two patients fully recovered and on follow up controls both patients are doing well.
Conclusions: Trauma events, and particularly gunshot wounds in pregnant women requires promptly and adequate intervention. Coordinated efforts from multidisciplinary clinical teams are needed as well as the appropriate training in maternal and infant resuscitative measures and surgical techniques
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