The author's main research activity for the last 20 years as a researcher and an academic teacher of physical oceanography has been in the field of satellite oceanography. This unique book reflects ...the breadth of that knowledge. It is the first academic text devoted to describing and explaining the impact that satellite image data have made to our understanding of how the ocean behaves.
The International Tundra Experiment (ITEX) is a collaborative, multisite experiment using a common temperature manipulation to examine variability in species response across climatic and geographic ...gradients of tundra ecosystems. ITEX was designed specifically to examine variability in arctic and alpine species response to increased temperature. We compiled from one to four years of experimental data from 13 different ITEX sites and used meta-analysis to analyze responses of plant phenology, growth, and reproduction to experimental warming. Results indicate that key phenological events such as leaf bud burst and flowering occurred earlier in warmed plots throughout the study period; however, there was little impact on growth cessation at the end of the season. Quantitative measures of vegetative growth were greatest in warmed plots in the early years of the experiment, whereas reproductive effort and success increased in later years. A shift away from vegetative growth and toward reproductive effort and success in the fourth treatment year suggests a shift from the initial response to a secondary response. The change in vegetative response may be due to depletion of stored plant reserves, whereas the lag in reproductive response may be due to the formation of flower buds one to several seasons prior to flowering. Both vegetative and reproductive responses varied among life-forms; herbaceous forms had stronger and more consistent vegetative growth responses than did woody forms. The greater responsiveness of the herbaceous forms may be attributed to their more flexible morphology and to their relatively greater proportion of stored plant reserves. Finally, warmer, low arctic sites produced the strongest growth responses, but colder sites produced a greater reproductive response. Greater resource investment in vegetative growth may be a conservative strategy in the Low Arctic, where there is more competition for light, nutrients, or water, and there may be little opportunity for successful germination or seedling development. In contrast, in the High Arctic, heavy investment in producing seed under a higher temperature scenario may provide an opportunity for species to colonize patches of unvegetated ground. The observed differential response to warming suggests that the primary forces driving the response vary across climatic zones, functional groups, and through time.
Endotoxin depresses cytochrome P450 levels when injected into animals. The purpose of this study was to determine whether endotoxin itself, or monokine(s) released in response to endotoxin ...administration are responsible for this effect. Cytochrome P450 levels and drug metabolizing activities were measured in endotoxin resistant C3H/HeJ mice 24h after single intraperitoneal injections of either lipopolysaccharide (LPS), a semipurified murine monokine preparation containing interleukin-1 (IL-1), or murine recombinant IL-1. In endotoxin sensitive C3H/HeN mice, LPS (0.5 mg/Kg) decreased total cytochrome P450 levels, benzphetamine demethylase activities, and ethoxyresorufin-0-deethylase activities. This dose of LPS did not alter cytochrome P450 levels or activities in the C3H/HeJ mice. However, after injection of the semipurified monokine preparation or the recombinant IL-1, there were significant decreases in cytochrome P450 levels and activities similar to the decreases observed with LPS in the C3H/HeN mice. These findings suggest that the alterations in hepatic cytochrome P450 seen with endotoxin injection are mediated, at least in part, by IL-1.
Previous studies suggested that risk for Autism Spectrum Disorder (ASD) may be increased in children exposed to antidepressants during the prenatal period. The disease specificity of this risk has ...not been addressed and the possibility of confounding has not been excluded. Children with ASD or attention-deficit hyperactivity disorder (ADHD) delivered in a large New England health-care system were identified from electronic health records (EHR), and each diagnostic group was matched 1:3 with children without ASD or ADHD. All children were linked with maternal health data using birth certificates and EHRs to determine prenatal medication exposures. Multiple logistic regression was used to examine association between prenatal antidepressant exposures and ASD or ADHD risk. A total of 1377 children diagnosed with ASD and 2243 with ADHD were matched with healthy controls. In models adjusted for sociodemographic features, antidepressant exposure prior to and during pregnancy was associated with ASD risk, but risk associated with exposure during pregnancy was no longer significant after controlling for maternal major depression (odds ratio (OR) 1.10 (0.70-1.70)). Conversely, antidepressant exposure during but not prior to pregnancy was associated with ADHD risk, even after adjustment for maternal depression (OR 1.81 (1.22-2.70)). These results suggest that the risk of autism observed with prenatal antidepressant exposure is likely confounded by severity of maternal illness, but further indicate that such exposure may still be associated with ADHD risk. This risk, modest in absolute terms, may still be a result of residual confounding and must be balanced against the substantial consequences of untreated maternal depression.
•An overview of the challenges faced when implementing environmental policy.•Factors affecting the success of management interventions are considered.•Human barriers to management interventions are ...discussed.•A logical step-wise framework supporting policy decision-making is presented.•Conclusions are drawn based on previous experience and lessons learnt.
An ecosystem approach forms the basis of many recent environmental policies. The underlying concept states that decision-makers must consider the environmental, social and economic costs and benefits in the course of deciding whether to implement a management action. Decision-making can be undermined by uncertainty. Here, we discuss potential sources of uncertainty and their effect on an ecosystem approach-driven environmental policy, the factors affecting the choice and potential for management actions to achieve their objectives, the challenges associated with setting realistic and achievable targets, and how we can prioritise management of detrimental activities. We also consider how human challenges such as the availability of infrastructure and political will and ways of measuring costs and benefits and Member State interactions could also undermine environmental management. Potential limitations along with areas where further effort may be required to support ecosystem-based management objectives are highlighted and the advantages of a structured step-wise interdisciplinary approach to ecosystem management is shown.
This is the first book in English devoted to the German king and emperor Henry IV (1056–1106), whose reign was one of the most momentous in German history and a turning-point in the history of the ...medieval empire (the kingdoms of Germany, Italy and Burgundy). The reign was marked by continuous rebellions and fluctuating fortune. Earlier monarchs had also witnessed conflict between crown and aristocracy, but Henry IV's reign differed in that his conflicts could never be definitively resolved either by negotiation or by war. During the 1070s the young king gained a lasting reputation for tyranny, while his assertion of the crown's traditional rights over the imperial church aroused papal opposition. The alliance between the German princes and the papacy haunted Henry IV for the rest of his life. He meanwhile, by turns opportunist and compromiser, dedicated himself at all times to preserving the traditional rights of the monarchy.
The purpose of this study was to determine whether oligonucleotides the size of siRNA are permeable to gap junctions and whether
a specific siRNA for DNA polymerase β (pol β) can move from one cell ...to another via gap junctions, thus allowing one cell
to inhibit gene expression in another cell directly. To test this hypothesis, fluorescently labelled oligonucleotides (morpholinos)
12, 16 and 24 nucleotides in length were synthesized and introduced into one cell of a pair using a patch pipette. These probes
moved from cell to cell through gap junctions composed of connexin 43 (Cx43). Moreover, the rate of transfer declined with
increasing length of the oligonucleotide. To test whether siRNA for pol β was permeable to gap junctions we used three cell
lines: (1) NRK cells that endogenously express Cx43; (2) Mβ16tsA cells, which express Cx32 and Cx26 but not Cx43; and (3)
connexin-deficient N2A cells. NRK and Mβ16tsA cells were each divided into two groups, one of which was stably transfected
to express a small hairpin RNA (shRNA), which gives rise to siRNA that targets pol β. These two pol β knockdown cell lines
(NRK-kcdc and Mβ16tsA-kcdc) were co-cultured with labelled wild type, NRK-wt or Mβ16tsA-wt cells or N2A cells. The levels
of pol β mRNA and protein were determined by semiquantitative RT-PCR and immunoblotting. Co-culture of Mβ16tsA-kcdc cells
with Mβ16tsA-wt, N2A or NRK-wt cells had no effect on pol β levels in these cells. Similarly, co-culture of NRK-kcdc with
N2A cells had no effect on pol β levels in the N2A cells. In contrast, co-culture of NRK-kcdc with NRK-wt cells resulted in
a significant reduction in pol β in the wt cells. The inability of Mβ16tsA-kcdc cells to transfer siRNA is consistent with
the fact that oligonucleotides of the 12 nucleotide length were not permeable to Cx32/Cx26 channels. This suggested that Cx43
but not Cx32/Cx26 channels allowed the cell-to-cell movement of the siRNA. These results support the novel hypothesis that
non-hybridized and possible hybridized forms of siRNA can move between mammalian cells through connexin-specific gap junctions.
Antibiotic resistance is the quintessential One Health issue Robinson, T. P.; Bu, D. P.; Carrique-Mas, J. ...
Transactions of The Royal Society of Tropical Medicine and Hygiene,
07/2016, Letnik:
110, Številka:
7
Journal Article, Publication
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