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Examination of the ecohydrological separation hypothesis in a humid subtropical area: Comparison of three methods
Get PDF© 2019 Elsevier B.V. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (February 2019) in accordance with the publisher’s archiving policyThe ecohydrological separation between soil water sources for plant water uptake and groundwater recharge has been recently examined in various climate zones primarily based on isotopic composition of water. The existence of the ecohydrological separation has profound implications for mechanistic ecohydrological modeling and water resource management. However, it is still unclear when and where the ecohydrological separation occurs, especially in humid regions. In this study, high frequency sampling of precipitation, bulk soil water, groundwater and twig xylem water for hydrogen and oxygen isotope composition measurement was conducted in a humid subtropical site in the central southern China from March 2017 to April 2018. We examined evidence of the ecohydrological separation with three methods (dual-isotope space, line-conditioned excess (lc-excess), and the piecewise isotope balance (PIB) method). The results show that the isotopic composition of plant xylem and bulk soil water are not distinguishable from those of precipitation water on the dual-isotope space due to a weak evaporation effect at the study site, indicating that there is no evidence of the ecohydrological separation. However, the other two methods support the ecohydrological separation in this humid area, with the results from the PIB method revealing more temporal details. The present study suggests that the ecohydrological separation can happen in subtropical humid climate. It is more likely to occur in spring and winter at the study site when plant-accessible water pool has been replenished by antecedent precipitation, while ecohydrological connection seems to occur during winter snowmelt. With the limitations of three methods, the caution should be taken when only one method is applied in examining the ecohydrological separation in such an environment
Temporal stability and specificity of high bipolar electrogram entropy regions in sustained atrial fibrillation: Implications for mapping
Get PDF© 2018 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Background
The potential utility of entropy (En) for atrial fibrillation (AF) mapping has been demonstrated in previous studies by multiple groups, where an association between high bipolar electrogram (EGM) entropy and the pivot of rotors has been shown. Though En is potentially attractive new approach to ablation, no studies have examined its temporal stability and specificity, which are critical to the application of entropy to clinical ablation. In the current study, we sought to objectively measure the temporal stability and specificity of bipolar EGM entropy in medium to long term recordings using three studies: i) a human basket catheter AF study, ii) a tachypaced sheep AF study and iii) a computer simulation study.
Objective
To characterize the temporal dynamics and specificity of Approximate, Sample and Shannon entropy (ApEn/SampEn/ShEn) in human (H), sheep (S), and computer simulated AF.
Methods
64-electrode basket bi-atria sustained AF recordings (H:15 min; S:40 min) were separated into 5 s segments. ShEn/ApEn/SampEn were computed, and co-registered with NavX 3D maps. Temporal stability was determined in terms of: (i) global pattern stability of En and (ii) the relative stability the top 10% of En regions. To provide mechanistic insights into underlying mechanisms, stability characteristics were compared to models depicting various propagation patterns. To verify these results, cross-validation was performed across multiple En algorithms, across species, and compared with dominant frequency (DF) temporal characteristics. The specificity of En was also determined by looking at the association of En to rotors and areas of wave cross propagation.
Results
Episodes of AF were analysed (H:26 epochs, 6040 s; S:15 epochs, 14,160 s). The global pattern of En was temporally unstable (CV- H:13.42% ± 4.58%; S:14.13% ± 8.13%; Friedman- H: p > 0.001; S: p > 0.001). However, within this dynamic flux, the top 10% of ApEn/SampEn/ShEn regions were relatively temporally stable (Kappa >0.6) whilst the top 10% of DF regions were unstable (Kappa <0.06). In simulated AF scenarios, the experimental data were optimally reproduced in the context of an AF pattern with stable rotating waves surrounded by wavelet breakup (Kappa: 0.610; p < 0.0001).
Conclusion
En shows global temporal instability, however within this dynamic flux, the top 10% regions exhibited relative temporal stability. This suggests that high En regions may be an appealing ablation target. Despite this, high En was associated with not just the pivot of rotors but also with areas of cross propagation, which suggests the need for future work before clinical application is possible
Demonstrating a new approach to planning and monitoring rural medical training distribution to meet population need in North West Queensland
Get PDFThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Background
Improving the health of rural populations requires developing a medical workforce with the right skills and a willingness to work in rural areas. A novel strategy for achieving this aim is to align medical training distribution with community need. This research describes an approach for planning and monitoring the distribution of general practice (GP) training posts to meet health needs across a dispersed geographic catchment.
Methods
An assessment of the location of GP registrars in a large catchment of rural North West Queensland (across 11 sub-regions) in 2017 was made using national workforce supply, rurality and other indicators. These included (1): Index of Access –spatial accessibility (2); 10-year District of Workforce Shortage (DWS) (3); MMM (Modified Monash Model) rurality (4); SEIFA (Socio-Economic Indicator For Areas) (5); Indigenous population and (6) Population size. Distribution was determined relative to GP workforce supply measures and population health needs in each health sub-region of the catchment. An expert panel verified the approach and reliability of findings and discussed the results to inform planning.
Results
378 registrars and 582 supervisors were well-distributed in two sub-regions; in contrast the distribution was below expected levels in three others. Almost a quarter of registrars (24%) were located in the poorest access areas (Index of Access) compared with 15% of the population located in these areas. Relative to the population size, registrars were proportionally over-represented in the most rural towns, those consistently rated as DWS or those with the poorest SEIFA value and highest Indigenous proportion.
Conclusions
Current regional distribution was good, but individual town-level data further enabled the training provider to discuss the nuance of where and why more registrars (or supervisors) may be needed. The approach described enables distributed workforce planning and monitoring applicable in a range of contexts, with increased sensitivity for registrar distribution planning where most needed, supporting useful discussions about the potential causes and solutions. This evidence-based approach also enables training organisations to engage with local communities, health services and government to address the sustainable development of the long-term GP workforce in these towns
Measuring disease activity and predicting response to intravenous immunoglobulin in chronic inflammatory demyelinating polyneuropathy
Get PDFThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Abstract
Chronic inflammatory demyelinating polyneuropathy (CIDP) is characterised by significant clinical heterogeneity and as such reliable biomarkers are required to measure disease activity and assess treatment response. Recent advances in our understanding of disease pathogenesis and the discovery of novel serum-based, electrophysiologic and imaging biomarkers allow clinicians to make more informed decisions regarding individualised treatment regimes.
As a chronic immune-mediated process typified by relapse following withdrawal of immunomodulatory therapy, a substantial proportion of patients with CIDP require long term treatment with intravenous immunoglobulin (IVIg), a scarce and expensive donor-derived resource. The required duration and intensity of immunoglobulin treatment vary widely between individuals, highlighting both the heterogeneous nature of the underlying disease process as well as the variable pharmacologic properties of IVIg.
This review outlines the use of multimodal biomarkers in the longitudinal evaluation of nerve injury and how recent developments have impacted our ability to predict both response to immunoglobulin administration and its withdrawal
Uncertainty analysis for seawater intrusion in fractured coastal aquifers: Effects of fracture location, aperture, density and hydrodynamic parameters
Get PDF© 2019 Elsevier B.V. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 24 month embargo from date of publication (February 2019) in accordance with the publisher’s archiving policyIn this study we use polynomial chaos expansion (PCE) to perform uncertainty analysis for seawater intrusion (SWI) in fractured coastal aquifers (FCAs) which is simulated using the coupled discrete fracture network (DFN) and variable-density flow (VDF) models. The DFN-VDF model requires detailed discontinuous analysis of the fractures. In real field applications, these characteristics are usually uncertain which may have a major effect on the predictive capability of the model. Thus, we perform global sensitivity analysis (GSA) to provide a preliminary assessment on how these uncertainties can affect the model outputs. As our conceptual model, we consider fractured configurations of the Henry Problem which is widely used to understand SWI processes. A finite element DFN-VDF model is developed in the framework of COMSOL Multiphysics®. We examine the uncertainty of several SWI metrics and salinity distribution due to the incomplete knowledge of fracture characteristics. PCE is used as a surrogate model to reduce the computational burden. A new sparse PCE technique is used to allow for high polynomial orders at low computational cost. The Sobol’ indices (SIs) are used as sensitivity measures to identify the key variables driving the model outputs uncertainties. The proposed GSA methodology based on PCE and SIs is useful for identifying the source of uncertainties on the model outputs with an affordable computational cost and an acceptable accuracy. It shows that fracture hydraulic conductivity is the first source of uncertainty on the salinity distribution. The imperfect knowledge of fracture location and density affects mainly the toe position and the total flux of saltwater entering the aquifer. Marginal effects based on the PCE are used to understand the effects of fracture characteristics on SWI. The findings provide a technical support for monitoring, controlling and preventing SWI in FCAs
Field assessment of microbial inoculants to control Rhizoctonia root rot on wheat
Get PDF© 2019 Elsevier Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license:
http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (February 2019) in accordance with the publisher’s archiving policyRhizoctonia root rot caused by Rhizoctonia solani AG8 is a major disease in dryland cereal crops. Previous research identified a suite of microbes using in planta bioassay screening that are effective as seed-coated inoculants for control of Rhizoctonia root rot on wheat. This paper assessed 23 strains in fields in Australia with a history of naturally occurring R. solani AG8. Due to the patchy nature of Rhizoctonia root rot in the field, a 2-phase split-plot field trial system was used to allow comparison for disease control efficacy in the same disease space. Seed applied strains were first assessed for their ability to reduce Rhizoctonia using ‘microplots’ which compare adjacent treated and untreated one metre rows. Up to 10% increases in plant growth and a 32% reduction in root disease was measured at eight weeks after sowing. Selected strains were then assessed in 20 m six row (3 + 3) split plots for their effects on early season wheat growth and root damage and for grain yield. A Paenibacillus and a Streptomyces strain were identified which were able to reduce root damage by 20% and 32% and increase grain yield by 4.2% and 2.8%, respectively, compared to untreated controls. The current best registered chemical control for Rhizoctonia root rot reduced root disease by 35% and increased yield by 3.0% in the same trial
Bilateral diffuse pulmonary infiltrates secondary to malignant peritoneal mesothelioma – A rare clinical presentation
Get PDF© 2019 The Authors. Published by Elsevier Ltd.
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/BY-NC-ND/4.0/).Diffuse pulmonary metastasis secondary to primary peritoneal malignant mesothelioma is rarely reported in the literature. In this report we describe a 59-year-old Caucasian women with no known previous asbestos exposure presenting with bilateral diffuse pulmonary opacities in association with primary malignant peritoneal mesothelioma. The diagnosis was confirmed by ultrasound guided abdominal and bronchoscopy, trans-bronchial lung biopsy. The biopsy demonstrated positive staining with AE1/3, CK7, CK5/6, WT1, calretinin and D2 40. The cells were negative for BerEP4, PAX8, CA125, ER, CD34, ERG, P63, P40, Melan A, Gata3 and mammaglobin. The morphology and immunohistochemical profile supported a diagnosis of epithelioid malignant mesothelioma
Nursing students' perceptions of a clinical learning assessment activity: ‘Linking the puzzle pieces of theory to practice’
Get PDF© 2019 Elsevier Ltd. This manuscript version is made available under the CC-BY-NC-ND 4.0 license:
http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (March 2019) in accordance with the publisher’s archiving policyThe nursing profession struggles with providing a bridge to close the theory to practice gap for students. Students are expected to graduate with competencies that promote their safe and comprehensive nursing care provision in accordance with professional standards. This paper reports on students' a simulated clinical educational intervention embedded into a second-year nursing student clinical topic offering experiential learning opportunities for a large cohort. Feedback was analysed using Braun and Clarke's (2006) thematic qualitative process to investigate student-learning experiences and present student perceptions of this experience. Three key themes were identified: support promoted learning, focus on the bigger picture and practice clarifies puzzle pieces. Students perceived the simulated clinical experience as beneficial to their confidence, learning and ability to develop their professional practice. Promotion of learning outcomes facilitated by the structured, supportive and educational approach was important for students. Nurse educators have a responsibility to develop learning experiences that enable student's ability to link theory to practice in context. Ongoing exploration and evaluation of this intervention is required however, such an approach appears to support student's knowledge development for transference across situations and within large student cohorts
Pharmaceutical and preclinical evaluation of Advax adjuvant as a dose-sparing strategy for ant venom immunotherapy
Get PDF© 2019 Elsevier B.V. This manuscript version is made available under the CC-BY-NC-ND 4.0 license:
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This author accepted manuscript is made available following 24 month embargo from date of publication (April 2019) in accordance with the publisher’s archiving policyA major challenge in broader clinical application of Jack Jumper ant venom immunotherapy (JJA VIT) is the scarcity of ant venom which needs to be manually harvested from wild ants. Adjuvants are commonly used for antigen sparing in other vaccines, and thereby could potentially have major benefits to extend JJA supplies if they were to similarly enhance JJA VIT immunogenicity. The purpose of this study was to evaluate the physicochemical and microbiological stability and murine immunogenicity of low-dose JJA VIT formulated with a novel polysaccharide adjuvant referred to as delta inulin or Advax™. Jack Jumper ant venom (JJAV) protein stability was assessed by UPLC-UV, SDS-PAGE, SDS-PAGE immunoblot, and ELISA inhibition. Diffraction light scattering was used to assess particle size distribution of Advax; pH and benzyl alcohol quantification by UPLC-UV were used to assess the physicochemical stability of JJAV diluent, and endotoxin content and preservative efficacy test was used to investigate the microbiological properties of the adjuvanted VIT formulation. To assess the effect of adjuvant on JJA venom immunogenicity, mice were immunised four times with JJAV alone or formulated with Advax adjuvant. JJA VIT formulated with Advax was found to be physicochemically and microbiologically stable for at least 2 days when stored at 4 and 25 °C with a trend for an increase in allergenic potency observed beyond 2 days of storage. Low-dose JJAV formulated with Advax adjuvant induced significantly higher JJAV-specific IgG than a 5-fold higher dose of JJAV alone, consistent with a powerful allergen-sparing effect. The pharmaceutical data provides important guidance on the formulation, storage and use of JJA VIT formulated with Advax adjuvant, with the murine immunogenicity studies providing a strong rationale for a planned clinical trial to test the ability of Advax adjuvant to achieve 4-fold JJAV dose sparing in JJA-allergic human patients
Effect of Flammulina velutipes on the physicochemical and sensory characteristics of Cantonese sausages
Get PDF© 2019 Elsevier Ltd. This manuscript version is made available under the CC-BY-NC-ND 4.0 license:
http://creativecommons.org/licenses/by-nc-nd/4.0/
This author accepted manuscript is made available following 12 month embargo from date of publication (April 2019) in accordance with the publisher’s archiving policyThe effects of fresh and dried Flammulina velutipes (FFV and DFV) on quality and sensory characteristics of Cantonese sausages were investigated. Sausage samples were prepared by adding 0% (control), 2.5% FFV, 2.5% and 5.0% DFV, respectively, and their nutritional compositions, free amino acid profiles, lipid and protein oxidation, color and texture properties were determined. Addition of F. velutipes significantly decreased fat content while increased free amino acid contents of Cantonese sausages. Total free amino acid contents of 2.5% FFV, 2.5% DFV and 5.0% DFV incorporation were 2.8-, 2.4- and 3.5-fold as compared to control, respectively. Lipid and protein oxidation of Cantonese sausages were effectively inhibited by the addition of F. velutipes. Both FFV and DFV addition decreased hardness and chewiness while showed different effect on yellowness of samples. DFV added at 2.5% exhibited the best overall sensory acceptance. Therefore, appropriate addition of F. velutipes may be an effective way to improve meat product quality and function