50 research outputs found
Alterations in microbial community composition with increasing fCO2: a mesocosm study in the eastern Baltic Sea
Ocean acidification resulting from the uptake of anthropogenic carbon
dioxide (CO<sub>2</sub>) by the ocean is considered a major threat to marine
ecosystems. Here we examined the effects of ocean acidification on microbial
community dynamics in the eastern Baltic Sea during the summer of 2012 when
inorganic nitrogen and phosphorus were strongly depleted. Large-volume in
situ mesocosms were employed to mimic present, future and far future
CO<sub>2</sub> scenarios. All six groups of phytoplankton enumerated by flow
cytometry ( < 20 µm cell diameter) showed distinct trends in
net growth and abundance with CO<sub>2</sub> enrichment. The picoeukaryotic
phytoplankton groups Pico-I and Pico-II displayed enhanced abundances, whilst
Pico-III, <i>Synechococcus</i> and the nanoeukaryotic phytoplankton groups
were negatively affected by elevated fugacity of CO<sub>2</sub>
(<i>f</i>CO<sub>2</sub>). Specifically, the numerically dominant eukaryote, Pico-I,
demonstrated increases in gross growth rate with increasing <i>f</i>CO<sub>2</sub>
sufficient to double its abundance. The dynamics of the prokaryote community
closely followed trends in total algal biomass despite differential effects
of <i>f</i>CO<sub>2</sub> on algal groups. Similarly, viral abundances corresponded
to prokaryotic host population dynamics. Viral lysis and grazing were both
important in controlling microbial abundances. Overall our results point to a
shift, with increasing <i>f</i>CO<sub>2</sub>, towards a more regenerative system
with production dominated by small picoeukaryotic phytoplankton.</p
Brain regions showing white matter loss in Huntington's Disease are enriched for synaptic and metabolic genes
Background The earliest white matter changes in Huntington’s disease are seen before disease onset in the premanifest stage around the striatum, within the corpus callosum, and in posterior white matter tracts. While experimental evidence suggests that these changes may be related to abnormal gene transcription, we lack an understanding of the biological processes driving this regional vulnerability. Methods Here, we investigate the relationship between regional transcription in the healthy brain, using the Allen Institute for Brain Science transcriptome atlas, and regional white matter connectivity loss at three time points over 24 months in subjects with premanifest Huntington’s disease relative to control participants. The baseline cohort included 72 premanifest Huntington’s disease participants and 85 healthy control participants. Results We show that loss of corticostriatal, interhemispheric, and intrahemispheric white matter connections at baseline and over 24 months in premanifest Huntington’s disease is associated with gene expression profiles enriched for synaptic genes and metabolic genes. Corticostriatal gene expression profiles are predominately associated with motor, parietal, and occipital regions, while interhemispheric expression profiles are associated with frontotemporal regions. We also show that genes with known abnormal transcription in human Huntington’s disease and animal models are overrepresented in synaptic gene expression profiles, but not in metabolic gene expression profiles. Conclusions These findings suggest a dual mechanism of white matter vulnerability in Huntington’s disease, in which abnormal transcription of synaptic genes and metabolic disturbance not related to transcription may drive white matter loss
The supernatural characters and powers of sacred trees in the Holy Land
This article surveys the beliefs concerning the supernatural characteristics and powers of sacred trees in Israel; it is based on a field study as well as a survey of the literature and includes 118 interviews with Muslims and Druze. Both the Muslims and Druze in this study attribute supernatural dimensions to sacred trees which are directly related to ancient, deep-rooted pagan traditions. The Muslims attribute similar divine powers to sacred trees as they do to the graves of their saints; the graves and the trees are both considered to be the abode of the soul of a saint which is the source of their miraculous powers. Any violation of a sacred tree would be strictly punished while leaving the opportunity for atonement and forgiveness. The Druze, who believe in the transmigration of souls, have similar traditions concerning sacred trees but with a different religious background. In polytheistic religions the sacred grove/forest is a centre of the community's official worship; any violation of the trees is regarded as a threat to the well being of the community. Punishments may thus be collective. In the monotheistic world (including Christianity, Islam and Druze) the pagan worship of trees was converted into the worship/adoration of saints/prophets; it is not a part of the official religion but rather a personal act and the punishments are exerted only on the violating individual
Biochemical composition of temperate and Arctic populations of Saccharina latissima after exposure to increased pCO2 and temperature reveals ecotypic variation
Discursive diversity in the textual articulation of epidemic disease in Early Modern England
This article provides a detailed examination of the way in which the social response to epidemic disease in Early Modern England was constructed through discourse, and of how a matrix of meanings for the ‘plague’ was promoted to fill the conceptual gap between experience and social understanding. It analyses the variety of textual genres that were used to articulate this response, from the sermon tradition to prose pamphlets and the bills of mortality, and considers the dialogic nature of the interaction between these genres and how this facilitated the spread and generation of metaphoric associations for the disease. The article also considers the way in which this discourse itself is structured, and how it is marked by diversity and heterogeneity; it contends that rather than there being a clear hierarchy of dominant and ‘alternative’ discourses, it is more an unstable equilibrium of competing explanations. In part, this diversity is a result of plural and competing meanings being ascribed to the disease; in part, it is due to the range of different voices eager to promote their own opinion. This results in multiplicity not just of ‘product’, but also of ‘process’, with different genres and institutional centres of power (including the church, the civic authorities, the publishing industry) all claiming authority over the prescription of meaning. In this way the discourse itself becomes disordered, as there is no major controlling influence, and the structure of the discourse can be seen to reflect iconically the very themes that it articulates
Regulation of Glyceraldehyde 3-Phosphate Dehydrogenase Expression by Metformin in HepG2 Cells
Ocular findings in Gillespie-like syndrome: Association with a new PAX6 mutation
Background: Gillespie syndrome is a rare variant form of aniridia, characterized by mental retardation, nonprogressive cerebellar ataxia, and iris hypoplasia. Unlike the more common dominant and sporadic forms of aniridia, there have been no associated PAX6 mutations or Wilms' tumor reported in Gillespie syndrome patients. Ocular findings in 21 cases published since Gillespie's initial description in 1965 include iris and foveal hypoplasia, nystagmus, and small optic discs with pigmentary retinopathy. Case report: We herein report a case of atypical Gillespie syndrome associated with bilateral ptosis, exotropia, corectopia, iris hypoplasia, anterior capsular lens opacities, foveal hypoplasia, retinal vascular tortuosity, and retinal hypopigmentation. Neurologic evaluation revealed a mild hand tremor and learning disability, but no ataxia or cerebellar abnormalities on neuroimaging. Sequencing studies revealed a substitution in intron 2 of the PAX6 gene (IVS2 + 2T > A). To our knowledge, this is the first mutation of PAX6 gene reported in association with a Gillespie-like syndrom
School Leadership and Management: Identifying Linkages with Learning and Structural Inequalities
RLOsThis chapter summarises three phases of research developments in South Africa that have successively brought more reliable quantitative evidence to bear on what we know about the linkages between school leadership and management (SLM) and learning outcomes. A common thread emerging through these studies is the educational value of managing time-on-task and curriculum coverage although more recent evidence suggests that the efficacy of these management practices in raising learning may be mediated through teacher capacity. These linkages are also only informed through mere associations rather than causal evidence. Notwithstanding the lack of rigorous casual evidence in South Africa on how to raise the quality of management in schools, analyses of distributional patterns and trends in school management team (SMT) post-provisioning reflect key areas that could be targeted to at least improve the quantity of SLM in schools and reduce related inequalities. While international evidence on the educational value of leaders and managers supports calls for the capacity development of SMTs, ensuring SMT members are allocated to schools and selecting the best people for these jobs at the outset are the first steps to improve and level differences in the school leadership and management landscape