Impacts of Increasing Greenhouse Gas Concentrations and of Ozone Changes on the Atmospheric and Oceanic Circulation in the Southern Hemisphere

This thesis investigates the changes in the atmospheric and oceanic circulation in the Southern Hemisphere driven by the increase in anthropogenic greenhouse gases and by changes in stratospheric ozone during the second half of the twentieth century and the twenty-first century. The effect of the method used to account for ozone changes in coupled climate models on the results is additionally investigated. It is found that in the past, the formation of the Antarctic ozone hole is the main driver of dynamical changes in the Southern Hemisphere, such as the acceleration of the Brewer-Dobson Circulation and the strengthening and poleward shift of the tropospheric westerlies. In the future, ozone recovery and the increase in greenhouse gases following the high emission scenario SSP585 drive changes of opposite sign, with the effect of greenhouse gases dominating. However, ozone recovery mitigates the impact of the increase in greenhouse gases on the westerly winds, the Agulhas leakage and the Southern Ocean sea surface temperature. In the stratosphere, changes of similar magnitude were found due to ozone recovery and increasing greenhouse gases in the future. The increase in greenhouse gases leads to a planetary wavenumber 1 response in austral spring and, surprisingly, to a weakening of the Brewer-Dobson Circulation. This contrast the strengthening of the Brewer-Dobson Circulation that occurs during the rest of the year due to greenhouse gases. Greenhouse gases dominate the changes in precipitation over South Africa associated with ridging highs in the future. Ridging highs were categorized based on whether they are accompanied by Rossby wave breaking aloft or not and it was found that Rossby wave breaking mediates the impact of the increase in greenhouse gases on ridging highs and the amount of precipitation they contribute over South Africa

Effects of prescribed CMIP6 ozone on simulating the Southern Hemisphere atmospheric circulation response to ozone depletion

The Antarctic ozone hole has led to substantial changes in the Southern Hemisphere atmospheric circulation, such as the strengthening and poleward shift of the midlatitude westerly jet. Ozone recovery during the twenty-first century is expected to continue to affect the jet's strength and position, leading to changes in the opposite direction compared to the twentieth century and competing with the effect of increasing greenhouse gases. Simulations of the Earth's past and future climate, such as those performed for the Coupled Model Intercomparison Project Phase 6 (CMIP6), require an accurate representation of these ozone effects. Climate models that use prescribed ozone fields lack the important feedbacks between ozone chemistry, radiative heating, dynamics, and transport. In addition, when the prescribed ozone field was not generated by the same model to which it is prescribed, the imposed ozone hole is inconsistent with the simulated dynamics. These limitations ultimately affect the climate response to ozone depletion. This study investigates the impact of prescribing the ozone field recommended for CMIP6 on the simulated effects of ozone depletion in the Southern Hemisphere. We employ a new state-of-the-art coupled climate model, Flexible Ocean Climate Infrastructure (FOCI), to compare simulations in which the CMIP6 ozone is prescribed with simulations in which the ozone chemistry is calculated interactively. At the same time, we compare the roles played by ozone depletion and by increasing concentrations of greenhouse gases in driving changes in the Southern Hemisphere atmospheric circulation using a series of historical sensitivity simulations. FOCI captures the known effects of ozone depletion, simulating an austral spring and summer intensification of the midlatitude westerly winds and of the Brewer–Dobson circulation in the Southern Hemisphere. Ozone depletion is the primary driver of these historical circulation changes in FOCI. The austral spring cooling of the polar cap in the lower stratosphere in response to ozone depletion is weaker in the simulations that prescribe the CMIP6 ozone field. We attribute this weaker response to a prescribed ozone hole that is different to the model dynamics and is not collocated with the simulated polar vortex, altering the strength and position of the planetary wavenumber one. As a result, the dynamical contribution to the ozone-induced austral spring lower-stratospheric cooling is suppressed, leading to a weaker cooling trend. Consequently, the intensification of the polar night jet is also weaker in the simulations with prescribed CMIP6 ozone. In contrast, the differences in the tropospheric westerly jet response to ozone depletion fall within the internal variability present in the model. The persistence of the Southern Annular Mode is shorter in the prescribed ozone chemistry simulations. The results obtained with the FOCI model suggest that climate models that prescribe the CMIP6 ozone field still simulate a weaker Southern Hemisphere stratospheric response to ozone depletion compared to models that calculate the ozone chemistry interactively

Temporal dynamics of gene expression in the lung in a baboon model of E. coli sepsis

BACKGROUND: Bacterial invasion during sepsis induces disregulated systemic responses that could lead to fatal lung failure. The purpose of this study was to relate the temporal dynamics of gene expression to the pathophysiological changes in the lung during the first and second stages of E. coli sepsis in baboons. RESULTS: Using human oligonucleotide microarrays, we have explored the temporal changes of gene expression in the lung of baboons challenged with sublethal doses of E. coli. Temporal expression pattern and biological significance of the differentially expressed genes were explored using clustering and pathway analysis software. Expression of selected genes was validated by real-time PCR. Cytokine levels in tissue and plasma were assayed by multiplex ELISA. Changes in lung ultrastructure were visualized by electron microscopy. We found that genes involved in primary inflammation, innate immune response, and apoptosis peaked at 2 hrs. Inflammatory and immune response genes that function in the stimulation of monocytes, natural killer and T-cells, and in the modulation of cell adhesion peaked at 8 hrs, while genes involved in wound healing and functional recovery were upregulated at 24 hrs. CONCLUSION: The analysis of gene expression modulation in response to sepsis provides the baseline information that is crucial for the understanding of the pathophysiology of systemic inflammation and may facilitate the development of future approaches for sepsis therapy

On the Ridging of the South Atlantic Anticyclone Over South Africa: The Impact of Rossby Wave Breaking and of Climate Change

Ridging South Atlantic Anticyclones contribute an important amount of precipitation over South Africa. Here, we use a global coupled climate model and the ERA5 reanalysis to separate for the first time ridging highs (RHs) based on whether they occur together with Rossby wave breaking (RWB) or not. We show that the former type of RHs are associated with more precipitation than the latter type. The mean sea level pressure anomalies caused by the two types of RHs are characterized by distinct patterns, leading to differences in the flow of moisture-laden air onto land. We additionally find that RWB mediates the effect of climate change on RHs during the twenty-first century. Consequently, RHs occurring without RWB exhibit little change, while those occurring with RWB contribute more precipitation over the southern and less precipitation over the northeastern South Africa in the future. Key Points: - Ridging South Atlantic Anticyclones are accompanied by Rossby wave breaking (RWB) aloft in 44% of the cases - Ridging highs that are accompanied by RWB lead to more precipitation over South Africa than those that are not - Ridging highs bring more precipitation over the southern and less precipitation over the northeastern part of South Africa in the futur

Forensic aspects in animal abuse/cruelty: negative behaviors of humans towards the livestock

Abuses (cruelty) are instances of inappropriate treatment of animals by careers or persons interacting with the animal as part of the production process, such as before sacrifice or during shearing. These circumstances are then generalized on a large scale, leading to the spread of this behavior and posing a serious risk to animal welfare. It is important to establish the prevalence of behaviors, the reasons for the occurrence and the appropriate responses from livestock communities. These issues need to be taken into account in the context in which we have a moral duty towards the animals we care for and provide us with consumer goods. In general, the idea is to use animals for the company, food or clothing, an idea embraced even by many who do not consume meat but buy meat products for feeding their pets. Animals that provide these resources are dependent on people for food and shelter throughout their lives. Therefore, we have a duty to care for those animals that depend on us. In our research, the prevalence of deliberate maltreatment of animals in the county of Iasi was monitored. This does not mean that there were no occasions when an individual harmed the animal due to a certain set of circumstances, such as the animal's response to orders or because the person is upset about other reasons or is not feeling well. Cases of animal abuse are numerous, from precarious housing, to starvation, beating and even slaughter in barbaric conditions. Under existing laws (Law 205/2004 modified and republished in 2017) on animal welfare, a person commits the offense of cruelty to animals when the person causes death or unjustifiable physical pain or suffering to any animal by an act, an omission, or willful neglect

Defective angiogenesis and fatal embryonic hemorrhage in mice lacking core 1–derived O-glycans

The core 1 β1-3-galactosyltransferase (T-synthase) transfers Gal from UDP-Gal to GalNAcα1-Ser/Thr (Tn antigen) to form the core 1 O-glycan Galβ1-3GalNAcα1-Ser/Thr (T antigen). The T antigen is a precursor for extended and branched O-glycans of largely unknown function. We found that wild-type mice expressed the NeuAcα2-3Galβ1-3GalNAcα1-Ser/Thr primarily in endothelial, hematopoietic, and epithelial cells during development. Gene-targeted mice lacking T-synthase instead expressed the nonsialylated Tn antigen in these cells and developed brain hemorrhage that was uniformly fatal by embryonic day 14. T-synthase–deficient brains formed a chaotic microvascular network with distorted capillary lumens and defective association of endothelial cells with pericytes and extracellular matrix. These data reveal an unexpected requirement for core 1–derived O-glycans during angiogenesis

The hope and reality of long‐acting hemophilia products

Recombinant DNA technology and protein engineering are creating hope that we can address ongoing challenges in hemophilia care such as reducing the costs of therapy, increasing the availability to the developing world, and improving the functional properties of these proteins. Technological advances to improve the half‐life of recombinant clotting factors have brought long‐acting clotting factors for hemophilia replacement therapy closer to reality. Preclinical and clinical trial results are reviewed as well as the potential benefits and risks of these novel therapies. Am. J. Hematol. 2012. © 2012 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91179/1/23146_ftp.pd

ASF Exit Strategy: Providing cumulative evidence of the absence of African swine fever virus circulation in wild boar populations using standard surveillance measures

EFSA assessed the role of seropositive wild boar in African swine fever (ASF) persistence. Surveillance data from Estonia and Latvia investigated with a generalised equation method demonstrated a significantly slower decline in seroprevalence in adult animals compared with subadults. The seroprevalence in adults, taking more than 24 months to approach zero after the last detection of ASFV circulation, would be a poor indicator to demonstrate the absence of virus circulation. A narrative literature review updated the knowledge on the mortality rate, the duration of protective immunity and maternal antibodies and transmission parameters. In addition, parameters potentially leading to prolonged virus circulation (persistence) in wild boar populations were reviewed. A stochastic explicit model was used to evaluate the dynamics of virus prevalence, seroprevalence and the number of carcasses attributed to ASF. Secondly, the impact of four scenarios on the duration of ASF virus (ASFV) persistence was evaluated with the model, namely a: (1) prolonged, lifelong infectious period, (2) reduction in the case‐fatality rate and prolonged transient infectiousness; (3) change in duration of protective immunity and (4) change in the duration of protection from maternal antibodies. Only the lifelong infectious period scenario had an important prolonging effect on the persistence of ASF. Finally, the model tested the performance of different proposed surveillance strategies to provide evidence of the absence of virus circulation (Exit Strategy). A two‐phase approach (Screening Phase, Confirmation Phase) was suggested for the Exit Strategy. The accuracy of the Exit Strategy increases with increasing numbers of carcasses collected and tested. The inclusion of active surveillance based on hunting has limited impact on the performance of the Exit Strategy compared with lengthening of the monitoring period. This performance improvement should be reasonably balanced against an unnecessary prolonged ‘time free’ with only a marginal gain in performance. Recommendations are provided for minimum monitoring periods leading to minimal failure rates of the Exit Strategy. The proposed Exit Strategy would fail with the presence of lifelong infectious wild boar. That said, it should be emphasised that the existence of such animals is speculative, based on current knowledge.info:eu-repo/semantics/publishedVersio