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Long-term conservation agriculture increases sulfur pools in soils together with increased soil organic carbon compared to conventional practices
No full textLong term depletion of sulfur (S) in soils is common in many cropping systems globally, and especially in intensive, rice-based rotations in Asia. We hypothesized that Conservation Agriculture (CA) practices (minimal soil disturbance and crop residue retention) will increase S in soils primarily through changes in soil organic carbon (SOC). A long term experiment was sampled after 24 crops of continuous practice of (A) contrasting soil disturbance (strip planting = SP and conventional tillage = CT) and (B) two levels of crop residue retention (low residue = LR and high residue = HR). Sulfur fractions and dynamics in soil at five depths (0–5, 5–15, 15–30, 30–45 and 45–60 cm) along with bulk density (BD), pH, SOC, total nitrogen (TN) and extractable nutrients were determined. Levels of total S (584 – 668 mg kg−1), organic S (50.0– 153 mg kg−1), available S (7.9 – 21.6 mg kg−1) and water soluble S (6.0 – 17.0 mg kg−1) were the highest in SP with HR (P < 0.05), while inorganic S (505 – 533 mg kg−1) and adsorbed S (2.3 – 4.4 mg kg−1) were significantly higher (P < 0.05) in HR plots irrespective of tillage systems at 0–30 cm soil depth. All the S fractions were positively and strongly correlated with SOC and except for inorganic and adsorbed S, all other S fractions were positively correlated with TN, extractable P, Zn, B and Fe. All S fractions were negatively correlated with BD. Inorganic S was the dominant S fraction but highly significant and positive correlations of available S with organic S (r = 0.92) and water–soluble S (r = 0.92) suggests these two fractions were the main sources of plant available S. This study suggests that both minimal soil disturbance and increased crop residue retention, core components of CA, increased S pools in soils primarily due to increased SOC sequestration
Research priorities of the Australian Chiropractic Profession: A Cross-Sectional survey of academics and practitioners
No full textObjective
The purpose of this study was to explore the research priorities of Australian practicing chiropractors and academics across a set of research domains to determine the agreement or disagreement based on these domains.
Methods
We conducted a pilot-tested online survey focusing on the following 5 principal research domains: basic science, conditions (disorders chiropractors may encounter), patient subgroups, clinical interventions, and practice and public health/health services. Responses were sought regarding support for funding research scholarships, practice-based research networks, scientific conferences/symposia, journals, and existing research agendas. Data were collected (February 19 to May 24, 2019) from a sample of chiropractic academics (n1 = 33) representing 4 Australian programs and practicing chiropractors (n2 = 340). Collected data were ranked and analyzed to determine agreement across domains and items.
Results
There was agreement between the 2 groups across the majority (>90%) of domain items. The closest agreement and highest rankings were achieved for the “clinical interventions and practice” and “conditions” domains. Disagreement was observed within specific domain items, such as patient subgroups (infants), and for 1 intervention (chiropractic-specific techniques). Disagreement also occurred outside of the main domains, including research agenda support and funding.
Conclusions
There was overall agreement between practicing chiropractors and academics across most research area domain items, which should help facilitate consensus-led development of any potential Australian Chiropractic research agenda. Disagreements across specific domain items, such as population subgroups, interventions, and funding require further investigation
A World of choices: Exploring the use of a simulation game in engaging the public with climate change
Get PDFPoor mental models of the climate system can be a significant barrier to engaging with the issue of climate change. Simulation games are a powerful tool for improving mental models, supporting doubleloop learning whereby players improve the conceptual structure and explanatory power of their mental models. However, few currently available climate change games include models incorporating the key physical principles that underpin the understanding of climate science. For this project, a prototype of a climate change game was developed incorporating intermediate complexity climate simulations, in which players could alter different climate variables to construct new planets for alien species. It was play-tested by participants to investigate the effect it had on players’ mental models of the climate system. Participants were selected to represent a range of interpretive communities observed in a sample of 90 respondents from an audience segmentation survey. Qualitative methods were used to investigate the effect playing the game had on participants’ elicited mental models of the climate system, using a think aloud protocol and telemetry data recorded during gameplay. Their mental models were compared to an expert model using semantic comparison measures. In general, mental models which were weaker prior to playing the game underwent the largest semantic changes, becoming closer to an expert understanding, while stronger mental models changed least. Participants’ understanding of climate concepts they were already familiar with tended to improve – such as temperature, CO2 and vegetation, while more complex and unfamiliar concepts such as Surface Albedo were not assimilated. Participants from highly engaged interpretive communities improved their familiarity with climate concepts the most. These findings indicate that simulation games incorporating climate models do have potential to improve players’ mental models of the climate system and could reduce some barriers to engaging with the issue
Precision medicine in allergy and immunology through the lens of immunogenomics
No full textNo abstract availabl
Adsorption performance of zinc semiconductor nanoparticles in tetracycline removal
No full textZinc semiconductor nanoparticles have been employed as potential adsorbents for the remediation of organic pollutants. However, the influence of its non-metallic components on the adsorption performance of zinc semiconductor nanoparticles is yet to be understood. Herein, using zinc oxide (ZnO) and zinc chalcogenide (ZnS) as adsorbents, we demonstrated the effect of O and S constituents on the adsorption performance of zinc semiconductor nanoparticles. The morphology, crystallinity, surface area, thermal stability, and the functionals group of both samples were investigated using scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), Brunauer–Emmett–Teller (BET), thermogravimetric analysis (TGA), Fourier Transform Resonance Spectroscopy (FT-IR), respectively. Although the surface area of ZnS was observed to be 26 times that of ZnO, the Langmuir adsorption capacity for (TC) of the latter (78.70 mg/g) was significantly higher than the former (47.79 mg/g). The enhanced adsorption performance by ZnO is ascribed to its high porosity and broader point of zero charges (PZC). The present study establishes the impact of S and O on the adsorption performance of zinc nanoparticle adsorbents
Optimized systematic review tool: Application to candidate biomarkers for the diagnosis of hepatocellular carcinoma
No full textThis review aims to develop an appropriate review tool for systematically collating metabolites that are dysregulated in disease and applies the method to identify novel diagnostic biomarkers for hepatocellular carcinoma (HCC). Studies that analyzed metabolites in blood or urine samples where HCC was compared with comparison groups (healthy, precirrhotic liver disease, cirrhosis) were eligible. Tumor tissue was included to help differentiate primary and secondary biomarkers. Searches were conducted on Medline and EMBASE. A bespoke “risk of bias” tool for metabolomic studies was developed adjusting for analytic quality. Discriminant metabolites for each sample type were ranked using a weighted score accounting for the direction and extent of change and the risk of bias of the reporting publication. A total of 84 eligible studies were included in the review (54 blood, 9 urine, and 15 tissue), with six studying multiple sample types. High-ranking metabolites, based on their weighted score, comprised energy metabolites, bile acids, acylcarnitines, and lysophosphocholines. This new review tool addresses an unmet need for incorporating quality of study design and analysis to overcome the gaps in standardization of reporting of metabolomic data. Validation studies, standardized study designs, and publications meeting minimal reporting standards are crucial for advancing the field beyond exploratory studies
Comparison of effects of an endotracheal tube or facemask on breathing pattern and distribution of ventilation in anesthetized horses
Get PDFEquine respiratory physiology might be influenced by the presence of an endotracheal tube (ETT). This experimental, randomized cross-over study aimed to compare breathing pattern (BrP) and ventilation distribution in anesthetized horses spontaneously breathing room air via ETT or facemask (MASK). Six healthy adult horses were anesthetized with total intravenous anesthesia (TIVA; xylazine, ketamine, guaiphenesin), breathing spontaneously in right lateral recumbency, and randomly assigned to ETT or MASK for 30 min, followed by the other treatment for an additional 30 min. During a second anesthesia 1 month later, the treatment order was inversed. Electrical impedance tomography (EIT) using a thoracic electrode belt, spirometry, volumetric capnography, esophageal pressure difference (ΔPoes), venous admixture, and laryngoscopy data were recorded over 2 min every 15 min. Breaths were classified as normal or alternate (sigh or crown-like) according to the EIT impedance curve. A mixed linear model was used to test the effect of treatment on continuous outcomes. Cochran-Mantel-Haenszel analysis was used to test for associations between global BrP and treatment. Global BrP was associated with treatment (p = 0.012) with more alternate breaths during ETT. The center of ventilation right-to-left (CoVRL) showed more ventilation in the non-dependent lung during ETT (p = 0.025). The I:E ratio (p = 0.017) and ΔPoes (p < 0.001) were smaller, and peak expiratory flow (p = 0.009) and physiologic dead space (p = 0.034) were larger with ETT. The presence of an ETT alters BrP and shifts ventilation toward the non-dependent lung in spontaneously breathing horses anesthetized with TIVA
Investigating the magnitude, timing and causes of abortion and lamb mortality in maiden ewes
Get PDFThe reproductive performance of maiden (primiparous) ewes is an important component of overall sheep flock performance in Australia. However, the reproductive performance of maiden ewes that are mated for the first time either as ewe lambs at 7 to 10 months of age, or hoggets, at 18 to 20 months of age is poor and inconsistent. Lamb mortalities in the perinatal period are a major source of reproductive inefficiency and a major welfare concern, with approximately 20-30% of lambs born in Australia dying at or after birth. However, most industry data for lamb survival is based on mature or mixed age ewes and do not distinguish between in utero losses and those that occur at or after birth. Consequently, the timing, magnitude and nature of losses that occur between pregnancy scanning and lamb marking in maiden ewe flocks in Australia are not well described.
Maiden ewes may be more susceptible to infectious diseases that cause abortion, stillbirths and the birth of weak lambs that are less likely to survive, as younger ewes are less likely to have developed immunocompetency to infection prior to pregnancy. In New Zealand, some studies have reported that infectious diseases are important contributors to the poor and inconsistent reproductive performance observed for maiden ewes, including an increased incidence of abortions in maiden ewe flocks. However, it is not clear if infectious diseases are an important contributor to foetal and lamb mortality for maiden ewes in Australia.
The overall objectives of the research described in this thesis was to i) identify the most common causes of ovine abortion and stillbirths diagnosed in Australia, ii) quantify abortion and lamb mortalities that occur in maiden ewe flocks between pregnancy scanning and lamb marking and iii) determine the impact of endemic abortigenic pathogens including Toxoplasma gondii, Neospora caninum, Coxiella burnetii, Campylobacter fetus and Campylobacter jejuni on the reproductive performance of maiden ewes.
A review of abortion and stillbirth investigations submitted to Australian veterinary laboratories revealed that an aetiological diagnosis was made for 57% of investigations. Of the investigations where an aetiological diagnosis was made, 81% involved infectious abortion, with Campylobacter spp. (32%), Listeria spp. (25%) and Toxoplasma gondii (9%) the three most common abortigenic pathogens implicated.
A cohort study was conducted between 2018 and 2020 involving 30 maiden ewe flocks located across South Australia (n=9), Western Australia (n=11) and Victoria (n=10). Foetal and lamb mortality from pregnancy scanning to marking were determined for 19 ewe lamb flocks (including composite breed, Border Leicester, Dorper, White Suffolk and Merino flocks) and 11 Merino hogget flocks (approximately 200 ewes per flock) based on two ultrasounds, lambing round records and ewe lactation status. Seropositivity to T gondii, N. caninum and C. burnetii was determined for a subset of maiden ewes that were predominantly determined to be pregnant and subsequently failed to rear a lamb (n = 1279). For flocks that had not been vaccinated against Campylobacter spp. (n=22), antibody titres for C. fetus and C. jejuni of 10 ewes that raised lambs and 10-20 ewes that aborted or had lambs that died in the perinatal period were determined.
Average foetal and lamb mortality from scanning to marking was 35.8% (range 14.3-71.1%) for ewe lamb flocks and 29.4% (range 19.7-52.7%) for Merino hogget flocks. Mid-pregnancy abortion was detected by sequential ultrasounds in 5.7% ewes (range 0-50%) in ewe lamb flocks and 0.9% ewes (range 0-4.4%) in hogget flocks. Lamb mortality from birth to marking represented the greatest contributor to overall lamb mortality after scanning. The proportion of sampled maiden ewes that were seropositive for T gondii, N. caninum and C. burnetti were 1.1% (95% confidence interval (CI) 0.6, 1.8), 0.16% (95% CI 0.03, 0.5) and 0.08% (95% CI 0.01, 0.36), respectively. Seropositivity to C. fetus and C. jejuni using titre cut-off ≥1:80 was demonstrated in 12% (57/462, 95% CI 9.6, 15.6) and 44% (204/462, 95% CI 39.7, 48.7) of maiden ewes, respectively. Campylobacter fetus-associated abortions were confirmed with microbial culture from aborted lambs in one flock in Victoria. The odds for failing to rear a lamb in maiden ewes with C. fetus titre ≥1:10 was 2.01 times that of seronegative ewes (95% CI 1.09, 3.77; P=0.027). However, there was no association between C. fetus titre ≥1:80 and failure to raise (OR 1.69 (95% CI 0.77, 3.76) P=0.191). Whilst C. jejuni was detected in all flocks, there was no evidence that seropositivity to C. jejuni was associated with increased odds of failing to rear at either titre threshold. Chlamydia pecorum was also detected via qPCR in tissue samples from aborted or stillborn lambs from five flocks in Western Australia.
This research highlights the variability in reproductive performance for maiden ewes and indicates scope to improve overall reproductive performance by reducing foetal and lamb mortality between pregnancy scanning and lamb marking. The low seropositivity to T. gondii, N. caninum and C. burnetii suggests that exposure to these pathogens was not widespread in ewes on farms located over a wide geographical region and were unlikely to be important contributors to abortion and perinatal mortalities observed in these flocks of maiden ewes. Campylobacter fetus– associated reproductive losses were confirmed on one farm in this study, consistent with the acknowledged role of Campylobacter spp. as a sporadic cause of ovine abortions in Australia. However, we observed that associations between seropositivity to Campylobacter spp. and reproductive outcomes were inconsistent, emphasising the importance of considering risk factors specific to the flock and pathogen detection at necropsy to confirm reproductive disease. The detection of C. pecorum, a bacterium more commonly associated with polyarthritis and conjunctivitis in sheep, was a notable observation, especially given the lack of epidemiological and geographic linkages between sites where the pathogen was detected. Further investigation to understand C. pecorum epidemiology and impacts on sheep reproduction are required.
Disease investigations to establish an underlying cause are warranted for maiden ewe flocks with disappointing or inconsistent lamb survival to inform targeted strategies for addressing lamb survival and reducing the incidence of abortion. Implementing strategies to improve perinatal lamb survival are a priority for maiden ewe flocks, but identifying flocks where abortion is contributing to poor lamb survival and addressing risks for reproductive disease can improve reproductive performance
First report from supermarket chicken meat and genomic characterization of colistin resistance mediated by mcr-1.1 in ESBL-producing, multidrug-resistant Salmonella Minnesota
No full textPlasmid-borne colistin resistance is considered one of the most complex public health concerns worldwide. Several studies reported the presence of the mcr-1.1 harboring Salmonella from the foodstuffs worldwide; still, there is a knowledge gap about the occurrence of these isolates in the Middle East. In this study, we report an mcr-1.1-mediated colistin resistance in two multidrug-resistant (MDR) S. Minnesota (denoted as Sal_2 and Sal_10), with both being also extended-spectrum β-lactamase (ESBL) producing. These isolates have been recovered from two independent samples out of 315 chilled chicken meat tested from retail supermarkets in the United Arab Emirates (UAE). Based on whole-genome sequencing (WGS) analysis, both isolates belonged to the same Sequence Type (ST) ST548. They shared the same genes encoding resistance to the following antimicrobials: polymyxin (mcr-1.1), phenicol (floR), quinolone (qnrB19), aminoglycoside (aac(6′)-Iaa), tetracycline (tet(A)), and sulfonamide (sul2). However, the isolates featured different patterns of β-lactamase resistance genes, which included blaCTX-M-55 (ESBL-β-lactamase) and blaCMY-2 (AmpC-β-lactamase) in the isolate Sal_2, and blaTEM-215 (ESBL-β-lactamase) in the isolate Sal_10. WGS analysis inferred that both S. Minnesota isolates in this study carry an IncX4 plasmid harboring the mcr-1.1 variant. To understand the possible origin of the two mcr-1.1 carrying S. Minnesota isolated from retail chicken meat in this study, we conducted a phylogenomic analysis using available genomes of S. enterica, which harbored mcr-1.1 gene (n = 240, from the Middle East and Asian countries) deposited in the NCBI database. We found that Sal_2 and Sal_10 independently clustered together with other isolates detected in China, mainly from the chicken origin and to a lesser extent from human clinical origin. The finding of mcr-producing colistin-resistant strains in retail chicken meat warrants a more comprehensive One Health investigations involving strains from animals, retail food chains, and human clinical isolates at the national level in the UAE
The dimensions of geotourism with a spotlight on geodiversity in a subdued landscape
Get PDFLandscapes of high relief are often favoured tourist destinations and at the same time display complex geomorphology that may be the result of diverse geology summarised into the concept of geodiversity. In contrast areas of subdued landscape, while topographically unappealing, may also be geodiverse but need careful explanation and promotion to attract the geotourist. The mid-west of Western Australia is an area of low relief with a long history of weathering, ostensibly of little interest to visitors, is underlain by a diverse geology that is displayed in an incised landscape where erosion by rivers and the ocean displays geodiversity in attractive detail. The mid-west of Western Australia is the result of sedimentary basin formation during the separation of the Gondwanan Indian plate from the western edge of the Archean Yilgarn granitic craton. A plutonic Precambrian basement is overlain by Ordovician sediments comprising the Tumblagooda sandstone and then Permian and younger Mesozoic rocks, often capped with a complex weathered regolith. Geology is exposed in the Murchison and Irwin River valleys where interpretive signs explain the origin of the landscape and sequences of rock. Extensive weathering products from the Tertiary period, such as laterite and sandplains, provide opportunities to explain processes such as deep weathering, mobilisation and re-deposition of sediments that are integral to the development of landscapes in general. We thus provide a conceptual understanding of the nexus between tourism and geodiversity via the applied science of geotourism in a predominantly subdued landscape. We make the point that there is a general lack of attention paid to regolith in the geotourism literature, hence we have provided a relatively detailed account of a large expanse of sandplain that occurs in the study area. Furthermore, regolith geodiversity has not been investigated in the context of its wider geotourism potential and while this case study is preliminary in its wider scope, we provide a platform for further research