Transcriptional and environmental control of bacterial denitrification and N2O emissions

In oxygen-limited environments, denitrifying bacteria can switch from oxygen-dependent respiration to nitrate (NO3−) respiration in which the NO3− is sequentially reduced via nitrite (NO2−), nitric oxide (NO) and nitrous oxide (N2O) to dinitrogen (N2). However, atmospheric N2O continues to rise, a significant proportion of which is microbial in origin. This implies that the enzyme responsible for N2O reduction, nitrous oxide reductase (NosZ), does not always carry out the final step of denitrification either efficiently, or in synchrony with the rest of the pathway. Despite a solid understanding of the biochemistry underpinning denitrification, there is a relatively poor understanding of how environmental signals and respective transcriptional regulators control expression of the denitrification apparatus. This mini-review will describe the current picture for transcriptional regulation of denitrification in the model bacterium, Paracoccus denitrificans, highlighting differences in other denitrifying bacteria where appropriate, as well as gaps in our understanding. Alongside this, the emerging role of small regulatory RNAs (sRNAs) in regulation of denitrification will be discussed. We will conclude by speculating how this information, aside from providing a better understanding of the denitrification process, can be translated into development of novel greenhouse gas mitigation strategies

Novel Inducers of the Envelope Stress Response BaeSR in Salmonella Typhimurium: BaeR Is Critically Required for Tungstate Waste Disposal

The RpoE and CpxR regulated envelope stress responses are extremely important for SalmonellaTyphimurium to cause infection in a range of hosts. Until now the role for BaeSR in both the Salmonella Typhimurium response to stress and its contribution to infection have not been fully elucidated. Here we demonstrate stationary phase growth, iron and sodium tungstate as novel inducers of the BaeRregulon, with BaeR critically required for Salmonella resistance to sodium tungstate. We show that functional overlap between the resistance nodulation-cell division (RND) multidrug transporters, MdtA, AcrD and AcrB exists for the waste disposal of tungstate from the cell. We also point to a role for enterobactinsiderophores in the protection of enteric organisms from tungstate, akin to the scenario in nitrogen fixing bacteria. Surprisingly, BaeR is the first envelope stress response pathway investigated in S. Typhimurium that is not required for murine typhoid in either ityS or ityR mouse backgrounds. BaeR is therefore either required for survival in larger mammals such as pigs or calves, an avian host such as chickens, or survival out with the host altogether where Salmonella and related enterics must survive in soil and water

How Rapid is Rapid Prototyping? Analysis of ESPADON Programme Results

New methodologies, engineering processes, and support environments are beginning to emerge for embedded signal processing systems. The main objectives are to enable defence industry to field state-of-the-art products in less time and with lower costs, including retrofits and upgrades, based predominately on commercial off the shelf (COTS) components and the model-year concept. One of the cornerstones of the new methodologies is the concept of rapid prototyping. This is the ability to rapidly and seamlessly move from functional design to the architectural design to the implementation, through automatic code generation tools, onto real-time COTS test beds. In this paper, we try to quantify the term “rapid†and provide results, the metrics, from two independent benchmarks, a radar and sonar beamforming application subset. The metrics show that the rapid prototyping process may be sixteen times faster than a conventional process

Genome-Wide Discovery of Putative sRNAs in Paracoccus denitrificans Expressed under Nitrous Oxide Emitting Conditions

Nitrous oxide (N2O) is a stable, ozone depleting greenhouse gas. Emissions of N2O into the atmosphere continue to rise, primarily due to the use of nitrogen-containing fertilizers by soil denitrifying microbes. It is clear more effective mitigation strategies are required to reduce emissions. One way to help develop future mitigation strategies is to address the currently poor understanding of transcriptional regulation of the enzymes used to produce and consume N2O. With this ultimate aim in mind we performed RNA-seq on a model soil denitrifier, Paracoccus denitrificans, cultured anaerobically under high N2O and low N2O emitting conditions, and aerobically under zero N2O emitting conditions to identify small RNAs (sRNAs) with potential regulatory functions transcribed under these conditions. sRNAs are short (∼40–500 nucleotides) non-coding RNAs that regulate a wide range of activities in many bacteria. Hundred and sixty seven sRNAs were identified throughout the P. denitrificans genome which are either present in intergenic regions or located antisense to ORFs. Furthermore, many of these sRNAs are differentially expressed under high N2O and low N2O emitting conditions respectively, suggesting they may play a role in production or reduction of N2O. Expression of 16 of these sRNAs have been confirmed by RT-PCR. Ninety percent of the sRNAs are predicted to form secondary structures. Predicted targets include transporters and a number of transcriptional regulators. A number of sRNAs were conserved in other members of the α-proteobacteria. Better understanding of the sRNA factors which contribute to expression of the machinery required to reduce N2O will, in turn, help to inform strategies for mitigation of N2O emissions

A narrative synthesis of the impact of primary health care delivery models for refugees in resettlement countries on access, quality and coordination

Introduction. Refugees have many complex health care needs which should be addressed by the primary health care services, both on their arrival in resettlement countries and in their transition to long-term care. The aim of this narrative synthesis is to identify the components of primary health care service delivery models for such populations which have been effective in improving access, quality and coordination of care. Methods. A systematic review of the literature, including published systematic reviews, was undertaken. Studies between 1990 and 2011 were identified by searching Medline, CINAHL, EMBASE, Cochrane Library, Scopus, Australian Public Affairs Information Service-Health, Health and Society Database, Multicultural Australian and Immigration Studies and Google Scholar. A limited snowballing search of the reference lists of all included studies was also undertaken. A stakeholder advisory committee and international advisers provided papers from grey literature. Only English language studies of evaluated primary health care models of care for refugees in developed countries of resettlement were included. Results: Twenty-five studies met the inclusion criteria for this review of which 15 were Australian and 10 overseas models. These could be categorised into six themes: service context, clinical model, workforce capacity, cost to clients, health and non-health services. Access was improved by multidisciplinary staff, use of interpreters and bilingual staff, no-cost or low-cost services, outreach services, free transport to and from appointments, longer clinic opening hours, patient advocacy, and use of gender-concordant providers. These services were affordable, appropriate and acceptable to the target groups. Coordination between the different health care services and services responding to the social needs of clients was improved through case management by specialist workers. Quality of care was improved by training in cultural sensitivity and appropriate use of interpreters. Conclusion: The elements of models most frequently associated with improved access, coordination and quality of care were case management, use of specialist refugee health workers, interpreters and bilingual staff. These findings have implications for workforce planning and training

Pluralism about Knowledge

In this paper I consider the prospects for pluralism about knowledge, that is, the view that there is a plurality of knowledge relations. After a brief overview of some views that entail a sort of pluralism about knowledge, I focus on a particular kind of knowledge pluralism I call standards pluralism. Put roughly, standards pluralism is the view that one never knows anything simpliciter. Rather, one knows by this-or-that epistemic standard. Because there is a plurality of epistemic standards, there is a plurality of knowledge relations. In §1 I argue that one can construct an impressive case for standards pluralism. In §2 I clarify the relationship between standards pluralism, epistemic contextualism and epistemic relativism. In §3 I argue that standards pluralism faces a serious objection. The gist of the objection is that standards pluralism is incompatible with plausible claims about the normative role of knowledge. In §4 I finish by sketching the form that a standards pluralist response to this objection might take

The Clinical Impact of Continuing to Prescribe Antiretroviral Therapy in Patients with Advanced AIDS Who Manifest No Virologic or Immunologic Benefit

Introduction: Despite the efficacy and tolerability of modern antiretroviral therapy (ART), many patients with advanced AIDS prescribed these regimens do not achieve viral suppression or immune reconstitution as a result of poor adherence, drug resistance, or both. The clinical outcomes of continued ART prescription for such patients have not been well characterized. Methods: We examined the causes and predictors of all-cause mortality, AIDS-defining conditions, and serious non-AIDS-defining events among a cohort of participants in a clinical trial of pre-emptive therapy for CMV disease. We focused on participants who, despite ART had failed to achieve virologic suppression and substantive immune reconstitution. Results: 233 ART-receiving participants entered with a median baseline CD4+ T cell count of 30/mm3 and plasma HIV RNA of 5 log10 copies/mL. During a median 96 weeks of follow-up, 24.0% died (a mortality rate of 10.7/100 patient-years); 27.5% reported a new AIDS-defining condition, and 22.3% a new serious non-AIDS event. Of the deaths, 42.8% were due to an AIDS-defining condition, 44.6% were due to a non-AIDS-defining condition, and 12.5% were of unknown etiology. Decreased risk of mortality was associated with baseline CD4+ T cell count ≥25/mm3 and lower baseline HIV RNA. Conclusions: Among patients with advanced AIDS prescribed modern ART who achieve neither virologic suppression nor immune reconstitution, crude mortality percentages appear to be lower than reported in cohorts of patients studied a decade earlier. Also, in contrast to the era before modern ART became available, nearly half of the deaths in our modern-era study were caused by serious non-AIDS-defining events. Even among the most advanced AIDS patients who were not obtaining apparent immunologic and virologic benefit from ART, continued prescription of these medications appears to alter the natural history of AIDS—improving survival and shifting the causes of death from AIDS- to non-AIDS-defining conditions

Brown Marmorated Stink Bug [Halyomorpha halys (Stal)]

This fact sheet describes the brown marmorated stink bug, an invasive insect pest from eastern Asia. It includes a description of where it is found in Utah, host plants, crop injury and plant damage, general description of life stages, agricultural risks, monitoring, management, insecticides, and what to do if you find it

Powering production. The case of the sisal fibre production in the Tanga region, Tanzania

Energy plays a crucial role in economic development. The article presents a framework for the analysis of alternative energy technology mixes in agricultural production and applies it in the context of sisal production in the Tanga region, Tanzania. Through scenario analysis, the paper presents both case-specific and generalizable insights. Case-specific insights show the key role that modern uses of energy and modern agricultural technologies could play in increasing productivity and revenues, in minimizing environmental degradation, and in promoting local development. Generalizable insights demonstrate the value of using sector-specific micro-structural frameworks and scenario analysis for assessing different technologies mixes in the energy and agriculture planning process

Common Stink Bugs of Utah

This fact sheet provides information of some of Utah\u27s commonly encountered stink bugs, including what they look like, where to find them, and other key identifying characteristics