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Influence of turbidity on trophic plasticity in scleractinian corals in the Dampier Archipelago
Get PDFTropical scleractinian coral communities and coral reef biodiversity are in a state of decline due to cumulative global and anthropogenic stressors. However, some coral communities are able to survive, and indeed thrive, in stressful environments. The mechanisms that these corals employ to survive in challenging conditions are poorly understood. This study aimed to assess the influence of turbidity on the degree of trophic plasticity expressed by three genera of scleractinian corals (Acropora spp., Porites spp. and Platygyra spp.) and to investigate the temporal variations in the stable δ13C and δ15N isotopes of these three genera in the Dampier Archipelago, Western Australia. This study utilised stable isotope δ13C and δ15N analysis of whole and fractioned (separate host tissue and endosymbiont) corals in conjunction with modern Bayesian isotopic niche analysis to deliver several lines of evidence and provide a representation of the spatio-temporal variability of coral trophic plasticity. This study found that, (i) coral genera exhibited different levels of reliance on heterotrophy under different levels of turbidity, with both Platygyra spp. and Acropora spp. utilising mixotrophic (i.e. both autotrophic and heterotrophic) feeding strategies, whilst Porites spp. was more reliant on heterotrophic resources. (ii) In turbid environments all coral genera increased their reliance on heterotrophy, with clear evidence of a lack of resource sharing between symbiotic partners. (iii) Temporal environmental variability influenced the δ13C and δ15N signatures of corals, whereby signatures were δ13C enriched and δ15N depleted in the wet season (December – April), and the inverse occurred in the dry season (May – November). These results may reflect supressed photosynthetic rates in response to increased turbidity in the wet season. This study provides evidence that some scleractinian corals can adjust their feeding strategies in response to variable turbidity levels. As nearshore coral reefs are expected to become more turbid due to future climate change and anthropogenic activities, the knowledge from this study will allow for improved environmental impact assessment and predictive modelling for future coral reef conservation
Managing sands of the lower Mekong Basin to limit land degradation: A review of properties and limitations for crop and forage production
Get PDFLand development is rapidly occurring on sand-dominant soils that cover substantial areas of the Lower Mekong Basin (LMB). Sands are at risk of degradation on sloping uplands where agriculture is expanding and on lowland landscapes where intensification of cropping is occurring. Sandstone and granitic geology explain the prevalence of sand-dominant textures of profiles in the LMB. However, the sand terrains in uplands of Cambodia and Southern Laos mostly have not been mapped in detail and the diversity of their edaphic properties is poorly understood. On high-permeability sands, lowland rainfed rice crops are drought-prone, while nutrient losses from leaching are also a risk. Furthermore, waterlogging, inundation and subsoil hardpans are significant hazards that influence the choice of crops and forages for lowland soils. Soil acidity, low nutrient status, hard-setting and shallow rooting depth are significant constraints for crops and forages on sands in the lowlands. Land use change in the lowlands to alternative field crops and forages on sands is contingent on their profitability relative to rice, the amounts and reliability of early wet season rainfall, and the amounts of stored water available after harvesting rice. Low soil fertility and soil acidity are limitations to the productivity of farming systems on the sand profiles in uplands, while erosion, low soil organic matter levels and water balance are concerns for their sustainable use. Site-/soil-specific fertilizer and lime management, land suitability assessment and the use of conservation agriculture principles (minimum tillage and crop residue retention) can overcome some of these constraints
Analysis of the metabolic response of planktonic cells and biofilms of Klebsiella pneumoniae to sublethal disinfection with sodium hypochlorite measured by NMR
Get PDFKlebsiella pneumoniae is a pathogenic agent able to form biofilms on water storage tanks and pipe walls. This opportunistic pathogen can generate a thick layer as one of its essential virulence factors, enabling the bacteria to survive disinfection processes and thus develop drug resistance. Understanding the metabolic differences between biofilm and planktonic cells of the K. pneumoniae response to NaClO is key to developing strategies to control its spread. In this study, we performed an NMR metabolic profile analysis to compare the response to a sublethal concentration of sodium hypochlorite of biofilm and planktonic cells of K. pneumoniae cultured inside silicone tubing. Metabolic profiles revealed changes in the metabolism of planktonic cells after a contact time of 10 min with 7 mg L−1 of sodium hypochlorite. A decrease in the production of metabolites such as lactate, acetate, ethanol, and succinate in this cell type was observed, thus indicating a disruption of glucose intake. In contrast, the biofilms displayed a high metabolic heterogeneity, and the treatment did not affect their metabolic signature
Disturbance-Observer-Based Second-Order Sliding Mode Controller for Speed Control of PMSM Drives
No full textThis paper explicitly proposes a novel second-order sliding mode (SOSM) controller based on disturbance observer (DOB) to optimize the disturbance rejection property of the permanent magnet synchronous motor (PMSM) system. Firstly, to tackle the inevitable chattering problem in conventional firstorder sliding mode controllers, a new type of SOSM control technique is designed for the speed loop of PMSM system by retaining the discontinuous switching function in the derivative of the actual controller. The proposed controller can not only provide the strong anti-disturbance performance, but also significantly attenuate the potential chattering problem. Then, a DOB constructed based on the auxiliary system is further adopted to compensate the adverse effect generated by the disturbance to enhance dynamical performance. Finally, comprehensive experimental results are provided to verify the effectiveness of the proposed method
A traceable and revocable multi-authority access control scheme with privacy preserving for mHealth
No full textMobile healthcare (mHealth) is a smart health system, which makes people have the storage and share in their personal health data (PHD) in the cloud for rapidly medical treatment through mobile 5G-enabled Industrial Internet of Things (IIoT) equipments. But key hosting problem and privacy leakage problem issued by malicious users and revoked users bring new security challenges. Traceability and accountability to attackers have been an important issue in mHealth system. Among the methods solving the above, most of them still face key abusing and privacy leakage problems. In this article, an expressive privacy preserving attribute-based traceable approach is proposed, where it keeps PHD confidentiality, eliminates the key delegation issue and prevents the key from being abused, allowing for fine-grained access control to the shared data in mHealth. Under this framework, we imprint a robust unforgeable signature in the secret key to assure the tracked user’s undeniability. We also add a revocable function that can efficiently remove the malicious users by only updating parts of ciphertext, and unrevoked users still can access the encrypted data using the original key. To achieve privacy protection, a bloom filter is used to hide the access policy. Security analysis and performance comparisons show the proposed method is secure and efficient
2022 Update of the consensus on the rational use of antithrombotics and thrombolytics in Veterinary Critical Care (CURATIVE) Domain 6: Defining rational use of thrombolytics
Get PDFObjectives
To systematically review available evidence and establish guidelines related to the use of thrombolytics for the management of small animals with suspected or confirmed thrombosis.
Design
PICO (Population, Intervention, Control, and Outcome) questions were formulated, and worksheets completed as part of a standardized and systematic literature evaluation. The population of interest included dogs and cats (considered separately) and arterial and venous thrombosis. The interventions assessed were the use of thrombolytics, compared to no thrombolytics, with or without anticoagulants or antiplatelet agents. Specific protocols for recombinant tissue plasminogen activator were also evaluated. Outcomes assessed included efficacy and safety. Relevant articles were categorized according to level of evidence, quality, and as to whether they supported, were neutral to, or opposed the PICO questions. Conclusions from the PICO worksheets were used to draft guidelines, which were subsequently refined via Delphi surveys undertaken by the Consensus on the Rational Use of Antithrombotics and Thrombolytics in Veterinary Critical Care (CURATIVE) working group.
Results
Fourteen PICO questions were developed, generating 14 guidelines. The majority of the literature addressing the PICO questions in dogs is experimental studies (level of evidence 3), thus providing insufficient evidence to determine if thrombolysis improves patient-centered outcomes. In cats, literature was more limited and often neutral to the PICO questions, precluding strong evidence-based recommendations for thrombolytic use. Rather, for both species, suggestions are made regarding considerations for when thrombolytic drugs may be considered, the combination of thrombolytics with anticoagulant or antiplatelet drugs, and the choice of thrombolytic agent.
Conclusions
Substantial additional research is needed to address the role of thrombolytics for the treatment of arterial and venous thrombosis in dogs and cats. Clinical trials with patient-centered outcomes will be most valuable for addressing knowledge gaps in the field
Financial risk protection from out-of-pocket health spending in low- and middle-income countries: A scoping review of the literature
Get PDFBackground
Financial risk protection (FRP), defined as households’ access to needed healthcare services without experiencing undue financial hardship, is a critical health systems target, particularly in low- and middle-income countries (LMICs). Given the remarkable growth in FRP literature in recent times, we conducted a scoping review of the literature on FRP from out-of-pocket (OOP) health spending in LMICs. The objective was to review current knowledge, identify evidence gaps and propose future research directions.
Methods
We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines to conduct this scoping review. We systematically searched PubMed, Scopus, ProQuest and Web of Science in July 2021 for literature published since 1 January 2015. We included empirical studies that used nationally representative data from household surveys to measure the incidence of at least one of the following indicators: catastrophic health expenditure (CHE), impoverishment, adoption of strategies to cope with OOP expenses, and forgone care for financial reasons. Our review covered 155 studies and analysed the geographical focus, data sources, methods and analytical rigour of the studies. We also examined the level of FRP by disease categories (all diseases, chronic illnesses, communicable diseases) and the effect of health insurance on FRP.
Results
The extant literature primarily focused on India and China as research settings. Notably, no FRP study was available on chronic illness in any low-income country (LIC) or on communicable diseases in an upper-middle-income country (UMIC). Only one study comprehensively measured FRP by examining all four indicators. Most studies assessed (lack of) FRP as CHE incidence alone (37.4%) or as CHE and impoverishment incidence (39.4%). However, the LMIC literature did not incorporate the recent methodological advances to measure CHE and impoverishment that address the limitations of conventional methods. There were also gaps in utilizing available panel data to determine the length of the lack of FRP (e.g. duration of poverty caused by OOP expenses). The current estimates of FRP varied substantially among the LMICs, with some of the poorest countries in the world experiencing similar or even lower rates of CHE and impoverishment compared with the UMICs. Also, health insurance in LMICs did not consistently offer a higher degree of FRP.
Conclusion
The literature to date is unable to provide a reliable representation of the actual level of protection enjoyed by the LMIC population because of the lack of comprehensive measurement of FRP indicators coupled with the use of dated methodologies. Future research in LMICs should address the shortcomings identified in this review
Mitochondrial DNA variation in Parkinson’s disease: Analysis of “out-of-place” population variants as a risk factor
Get PDFMitochondrial DNA (mtDNA), a potential source of mitochondrial dysfunction, has been implicated in Parkinson’s disease (PD). However, many previous studies investigating associations between mtDNA population variation and PD reported inconsistent or contradictory findings. Here, we investigated an alternative hypothesis to determine whether mtDNA variation could play a significant role in PD risk. Emerging evidence suggests that haplogroup-defining mtDNA variants may have pathogenic potential if they occur “out-of-place” on a different maternal lineage. We hypothesized that the mtDNA of PD cases would be enriched for out-of-place variation in genes encoding components of the oxidative phosphorylation complexes. We tested this hypothesis with a unique dataset comprising whole mitochondrial genomes of 70 African ancestry PD cases, two African ancestry control groups (n = 78 and n = 53) and a replication group of 281 European ancestry PD cases and 140 controls from the Parkinson’s Progression Markers Initiative cohort. Significantly more African ancestry PD cases had out-of-place variants than controls from the second control group (P < 0.0125), although this association was not observed in the first control group nor the replication group. As the first mtDNA study to include African ancestry PD cases and to explore out-of-place variation in a PD context, we found evidence that such variation might be significant in this context, thereby warranting further replication in larger cohorts
Prevalence of Mycoplasma bovis Infection in calves and dairy cows in Western Australia
Get PDFMycoplasma bovis (M. bovis) can cause a multitude of diseases in cattle, with detrimental effects on the farm economy and the welfare of both adult and young cattle. The objective of this study was to determine the prevalence of M. bovis in adult cows and calves in the south-west region of Western Australia. A cross-sectional study was conducted on 29 dairy farms with 699 apparently healthy adult lactating cows and 495 young calves during 2019–2020. Nasal swabs and blood samples collected from the animals and bulk tank milk (BTM) samples were assessed for M. bovis-specific proteins and antibodies by using polymerase chain reaction (PCR) and Mycoplasma immunogenic lipase A- Enzyme-Linked Immune Sorbent Assay (MilA ELISA). A seroprevalence of 42.5% (95% CI: 38.9–46.2) and 61% (95% CI: 56.6–65.2) was found in adult lactating cows and calves, respectively. The herd-level seroprevalence of M. bovis ranged from 4% (95% CI: 07–19.5) to 92% (95% CI: 75.0–97.8) in adult lactating cows and 25% (95% CI: 10.2–49.5) to 87% (95% CI: 67.9–95.5) for calves in these farms. None of the BTM and nasal swab samples were positive for M. bovis, indicating an absence of any current active infections on the farms. The female calves and pure Holstein–Friesian animals are twice as likely to be seropositive for M. bovis compared to male calves (OR 2.4; 95% CI: 1.7–3.5) and Holstein–Friesian crossbred calves (OR 2.4; 95% CI: 1.7–3.5). The high seroprevalence in both adult and young cattle in the southwest dairy farms of Western Australia warrants more effective farm biosecurity measures and further evaluation of the current prevention and management measures practiced on the farms
Grain zinc and yield responses of two rice varieties to zinc biofortification and water management
Get PDFZinc (Zn) biofortification can improve grain yield and nutritional quality in rice, but its effectiveness is subject to agronomic practices and other factors. In a previous study, the application of Zn to soil enhanced grain Zn in lowland rice in well-drained and waterlogged soil, whereas grain Zn in upland rice increased only in well-drained soil. This new study explores the hypothesis that the application of foliar Zn can enhance grain Zn in upland and lowland rice grown under waterlogged and well-drained conditions. Two rice varieties, CNT1 (wetland rice) and KH CMU (upland rice) were grown in containers in waterlogged or well-drained soil with three Zn treatments (no Zn, soil Zn and foliar Zn). For the soil Zn treatment, 50 kg ZnSO4 ha−1 was applied to the soil before transplanting. For the foliar treatment, 0.5% ZnSO4 (equivalent to 900 L ha−1) was applied at booting and repeated at flowering and milky growth stages. Grain yield in CNT1 was 15.9% higher in the waterlogged than in the well-drained plants, but the water regime had no effect on grain yield in KH CMU. Grain Zn concentration in CNT1 increased from 19.5% to 32.6% above the no Zn control when plants were applied with soil or foliar Zn. In KH CMU, there was an interaction between the water regime and Zn treatment. Application of foliar Zn increased grain Zn by 44.6% in well-drained and 14.7% in waterlogged soil. The results indicate strong interaction effects between variety, water regime and Zn fertilizer application on Zn biofortification in rice. Thus, the selection of rice varieties and growing conditions should be considered in order for producers to achieve desirable outcomes from high grain Zn concentrations