343 research outputs found
(Wild)fire is not an ecosystem service
In their paper entitled âWildfires as an ecosystem
serviceâ, Pausas and Keeley (2019)
summarize the benefits generated by â as
well as the evolutionary and socioecological
importance of â wildfires for humankind.
Although we recognize the importance of
wildfires in such a context, we argue that
presenting wildfire per se as an ecosystem
service is conceptually incorrect and can be
misleading for policy makers and resource
managers. Throughout their paper, the
authors repeatedly refer to (wild)fire as a
potential provider of multiple ecosystem
services (and not as an ecosystem service
itself, as indicated in their articleâs title). We
believe that this is more than a dispute over
semantics, for such a contradiction could
lead to misperceptions about the definition
of the term â
ecosystem servicesâ, which is
especially concerning in light of its real-world
applications to fire management.ĂS received support from the Portuguese
Foundation for Science and Technology
(FCT) through PhD grant SFRH/BD/
132838/2017, funded by the Ministry
of Science, Technology and Higher
Education, and by the European Social
FundâOperational Program Human
Capital within the 2014â2020 EU
Strategic Framework. AR is funded by
Xunta de Galicia (post-doctoral
fellowship
ED481B2016/084-0).
This research
was developed as part of the project
FirESmart (PCIF/MOG/0083/2017), which
received funding from the FCT. The
authors declare that they have no conflicts
of interest.info:eu-repo/semantics/publishedVersio
Control of magnetic anisotropy by orbital hybridization in (La0.67Sr0.33MnO3)n/(SrTiO3)n superlattice
The asymmetry of chemical nature at the hetero-structural interface offers an
unique opportunity to design desirable electronic structure by controlling
charge transfer and orbital hybridization across the interface. However, the
control of hetero-interface remains a daunting task. Here, we report the
modulation of interfacial coupling of (La0.67Sr0.33MnO3)n/(SrTiO3)n
superlattices by manipulating the periodic thickness with n unit cells of
SrTiO3 and n unit cells La0.67Sr0.33MnO3. The easy axis of magnetic anisotropy
rotates from in-plane (n = 10) to out-of-plane (n = 2) orientation at 150 K.
Transmission electron microscopy reveals enlarged tetragonal ratio > 1 with
breaking of volume conservation around the (La0.67Sr0.33MnO3)n/(SrTiO3)n
interface, and electronic charge transfer from Mn to Ti 3d orbitals across the
interface. Orbital hybridization accompanying the charge transfer results in
preferred occupancy of 3d3z2-r2 orbital at the interface, which induces a
stronger electronic hopping integral along the out-of-plane direction and
corresponding out-of-plane magnetic easy axis for n = 2. We demonstrate that
interfacial orbital hybridization in superlattices of strongly correlated
oxides may be a promising approach to tailor electronic and magnetic properties
in device applications
Comparative cytogenetics of three species of Dichotomius (Coleoptera, Scarabaeidae)
Meiotic and mitotic chromosomes of Dichotomius nisus, D. semisquamosus and D. sericeus were analyzed after conventional staining, C-banding and silver nitrate staining. In addition, Dichotomius nisus and D. semisquamosus chromosomes were also analyzed after fluorescent in situ hybridization (FISH) with an rDNA probe. The species analyzed had an asymmetrical karyotype with 2n = 18 and meta-submetacentric chromosomes. The sex determination mechanism was of the Xyp type in D. nisus and D. semisquamosus and of the Xy r type in D. sericeus. C-banding revealed the presence of pericentromeric blocks of constitutive heterochromatin (CH) in all the chromosomes of the three species. After silver staining, the nucleolar organizer regions (NORs) were located in autosomes of D. semisquamosus and D. sericeus and in the sexual bivalent of D. nisus. FISH with an rDNA probe confirmed NORs location in D. semisquamosus and in D. nisus. Our results suggest that chromosome inversions and fusions occurred during the evolution of the group
Omega-3 supplementation from pregnancy to postpartum to prevent depressive symptoms: a randomized placebo-controlled trial
Background:
Low n-3 polyunsaturated fatty acids (PUFAs) has been linked to depression, but the preventive effect of n-3PUFAs supplementation on maternal depression needs further investigation. We aimed to evaluate the efficacy of a daily dose of n-3 PUFAs supplementation (fish oil) on the prevention of postpartum depression (PPD).
Methods:
A randomized, placebo-controlled, double blind trial was designed and nested into a cohort study conducted in Rio de Janeiro, Brazil. Sixty pregnant women identified as being at risk for PPD were invited and randomly assigned to receive fish oil capsules [1.8 g (1.08 g of Eicosapentaenoic (EPA) and 0.72 g of Docosapentaenoic (DHA) acids)] or placebo (control). The Edinburgh Postnatal Depression Scale (EPDS) was scored at 5â13 (T0, baseline), 22â24 (T1), 30â32 weeks of gestation (T2) and 4â6 weeksâ postpartum (T3). Supplementation started at week 22â24 of gestation (T1) and lasted for 16 weeks. Serum fatty acids were assayed to evaluate compliance. Prevalence of EPDS â„11 was the primary outcome, and mean and changes in EPDS score, length of gestation, and birth weight the secondary outcomes. Linear mixed-effect (LME) and random-intercept logistic regression models were performed to test the effect of fish oil supplementation on prevalence of EPDS â„11 and EPDS scores variation.
Results:
In intention-to-treat (ITT) analysis, at 30â32 weeksâ gestation women in the fish oil presented higher serum concentration of EPA, DHA and lower n-6/n-3 ratio comparing to the control group. There were no differences between intervention and control groups in the prevalence of EPDS â„11, EPDS scores over time, or in changes in EPDS scores from pregnancy to postpartum in either the ITT or per-protocol analyses. Women in the fish oil group with previous history of depression presented a higher reduction on the EPDS score from the second to the third trimester in the fish oil comparing to the control group in the ITT analyses [â1.0 (â3.0â0.0) vs. -0.0 (â1.0â3.0), P = 0.038). These results were confirmed on the LME model (ÎČ = â3.441; 95%CI: -6.532â -0.350, P = 0.029).
Conclusion:
Daily supplementation of 1.8 g of n-3 PUFAs during 16 weeks did not prevent maternal depressive symptoms in a sample of Brazilian women
Genetic characterization of morphologically variant strains of Paracoccidioides brasiliensis
Molecular characterization of Paracoccidioides brasiliensis variant strains that had been preserved under mineral oil for decades was carried out by random amplified polymorphic DNA analysis (RAPD). On P. brasiliensis variants in the transitional phase and strains with typical morphology, RAPD produced reproducible polymorphic amplification products that differentiated them. A dendrogram based on the generated RAPD patterns placed the 14 P. brasiliensis strains into five groups with similarity coefficients of 72%. A high correlation between the genotypic and phenotypic characteristics of the strains was observed. A 750 bp-RAPD fragment found only in the wild-type phenotype strains was cloned and sequenced. Genetic similarity analysis using BLASTx suggested that this RAPD marker represents a putative domain of a hypothetical flavin-binding monooxygenase (FMO)-like protein of Neurospora crassa.FiocruzBritish Council Progra
Belongingness in early secondary school: Key factors that primary and secondary schools need to consider
© 2015 Vaz et al. It is unknown if, and how, students redefine their sense of school belongingness after negotiating the transition to secondary school. The current study used longitudinal data from 266 students with, and without, disabilities who negotiated the transition from 52 primary schools to 152 secondary schools. The study presents the 13 most significant personal student and contextual factors associated with belongingness in the first year of secondary school. Student perception of school belongingness was found to be stable across the transition. No variability in school belongingness due to gender, disability or household-socio-economic status (SES) was noted. Primary school belongingness accounted for 22% of the variability in secondary school belongingness. Several personal student factors (competence, coping skills) and school factors (low-level classroom task-goal orientation), which influenced belongingness in primary school, continued to influence belongingness in secondary school. In secondary school, effort-goal orientation of the student and perception of their school's tolerance to disability were each associated with perception of school belongingness. Family factors did not influence belongingness in secondary school. Findings of the current study highlight the need for primary schools to foster belongingness among their students at an early age, and transfer students' belongingness profiles as part of the handover documentation. Most of the factors that influenced school belongingness before and after the transition to secondary are amenable to change
Key Aspects of Health Policy Development to Improve Surgical Services in Uganda
Recently, surgical services have been gaining greater attention as an integral part of public health in low-income countries due to the significant volume and burden of surgical conditions, growing evidence of the cost-effectiveness of surgical intervention, and global disparities in surgical care. Nonetheless, there has been limited discussion of the key aspects of health policy related to surgical services in low-income countries. Uganda, like other low-income sub-Saharan African countries, bears a heavy burden of surgical conditions with low surgical output in health facilities and significant unmet need for surgical care. To address this lack of adequate surgical services in Uganda, a diverse group of local stakeholders met in Kampala, Uganda, in May 2008 to develop a roadmap of key policy actions that would improve surgical services at the national level. The group identified a list of health policy priorities to improve surgical services in Uganda. The priorities were classified into three areas: (1) human resources, (2) health systems, and (3) research and advocacy. This article is a critical discussion of these health policy priorities with references to recent literature. This was the first such multidisciplinary meeting in Uganda with a focus on surgical services and its output may have relevance to health policy development in other low-income countries planning to improve delivery of surgical services
Intrinsic Mitochondrial Membrane Potential and Associated Tumor Phenotype Are Independent of MUC1 Over-Expression
We have established previously that minor subpopulations of cells with stable differences in their intrinsic mitochondrial membrane potential (ÎÏm) exist within populations of mammary and colonic carcinoma cells and that these differences in ÎÏm are linked to tumorigenic phenotypes consistent with increased probability of participating in tumor progression. However, the mechanism(s) involved in generating and maintaining stable differences in intrinsic ÎÏm and how they are linked to phenotype are unclear. Because the mucin 1 (MUC1) oncoprotein is over-expressed in many cancers, with the cytoplasmic C-terminal fragment (MUC1 C-ter) and its integration into the outer mitochondrial membrane linked to tumorigenic phenotypes similar to those of cells with elevated intrinsic ÎÏm, we investigated whether endogenous differences in MUC1 levels were linked to stable differences in intrinsic ÎÏm and/or to the tumor phenotypes associated with the intrinsic ÎÏm. We report that levels of MUC1 are significantly higher in subpopulations of cells with elevated intrinsic ÎÏm derived from both mammary and colonic carcinoma cell lines. However, using siRNA we found that down-regulation of MUC1 failed to significantly affect either the intrinsic ÎÏm or the tumor phenotypes associated with increased intrinsic ÎÏm. Moreover, whereas pharmacologically mediated disruption of the ÎÏm was accompanied by attenuation of tumor phenotype, it had no impact on MUC1 levels. Therefore, while MUC1 over-expression is associated with subpopulations of cells with elevated intrinsic ÎÏm, it is not directly linked to the generation or maintenance of stable alterations in intrinsic ÎÏm, or to intrinsic ÎÏm associated tumor phenotypes. Since the ÎÏm is the focus of chemotherapeutic strategies, these data have important clinical implications in regard to effectively targeting those cells within a tumor cell population that exhibit stable elevations in intrinsic ÎÏm and are most likely to contribute to tumor progression
Essential Surgery at the District Hospital: A Retrospective Descriptive Analysis in Three African Countries
In the first of two papers investigating surgical provision in eight district hospitals in Saharan African countries, Margaret Kruk and colleagues find low levels of surgical care provision suggesting unmet need for surgical services
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