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The effect of organic manure or green manure incorporation with reductions in chemical fertilizer on yield-scaled N2O emissions in a citrus orchard
No full textExcess chemical fertilizer application results in substantial N2O emission. Manure application into agricultural soil can reduce chemical fertilizer input while maintaining crop yield. However, little is known about the potential effects of reduction in chemical fertilizer with green manure or organic manure on yield-scaled N2O emissions in orchards. A two-year experiment was carried out in a citrus orchard, including (i) chemical fertilizer (urea), 0%, 70%, 85% and 100% of N supplied, respectively (CK, C70, C85, CF), (ii) organic manure (rapeseed cake) incorporation with 0%, 70%, 85% and 100% of N supplied from chemical fertilizer (OM, OMC70, OMC85, OMCF), (iii) green manure (smooth vetch) incorporation with 0%, 70%, 85% and 100% of N supplied from chemical fertilizer (GM, GMC70, GMC85, GMCF) treatments. The soil physical-chemical properties, N2O emissions and yields were measured during 2018–2019. N2O emissions were 1.57 and 1.80 kg N ha−1 yr−1 under CF treatment in 2018 and 2019, respectively, and decreased by 25.4%−31.6% under C70, 32.5%−55.4% under OMC70 and OMC85 treatments and by 16.1–32.2% under GMC70 and GMC85 treatments. The 70% N rate of chemical fertilizer was the optimal N rate for maximizing yield in no manure, organic manure and green manure treatments, respectively. The C70, OMC70 and GMC70 treatments both significantly decreased yield-scaled N2O emission with the lowest emission in OMC70 treatment relative to CF treatment. N2O fluxes in OMC70 and OMC85 treatments were mainly controlled by the DOC/NO3- ratio, while soil NH4+ was the dominant factor controlling N2O fluxes in GMC70 and GMC85 treatments, suggesting that more NH4+ provided from green manure than from organic manure contributed to higher N2O emission. We conclude that applying organic manure incorporation with 30% reductions of chemical fertilizer is a fertilizer management strategy worth pursuing for sustainable productivity and environmental protection in citrus orchards
Synergism between feremycorrhizal symbiosis and free-living diazotrophs leads to improved growth and nutrition of wheat under nitrogen deficiency conditions
Get PDFA controlled-environment study was conducted to explore possible synergistic interactions between the feremycorrhizal (FM) fungus Austroboletus occidentalis and soil free-living N2-fixing bacteria (diazotrophs). Wheat (Triticum aestivum) plants were grown under N deficiency conditions in a field soil without adding microbial inoculum (control: only containing soil indigenous microbes), or inoculated with a consortium containing four free-living diazotroph isolates (diazotrophs treatment), A. occidentalis inoculum (FM treatment), or both diazotrophs and A. occidentalis inoculums (dual treatment). After 7 weeks of growth, significantly greater shoot biomass was observed in plants inoculated with diazotrophs (by 25%), A. occidentalis (by 101%), and combined inoculums (by 106%), compared to the non-inoculated control treatment. All inoculated plants also had higher shoot nutrient contents (including N, P, K, Mg, Zn, Cu, and Mn) than the control treatment. Compared to the control and diazotrophs treatments, significantly greater shoot N content was observed in the FM treatment (i.e., synergism between the FM fungus and soil indigenous diazotrophs). Dually inoculated plants had the highest content of nutrients in shoots (e.g., N, P, K, S, Mg, Zn, Cu, and Mn) and soil total N (13–24% higher than the other treatments), i.e., synergism between the FM fungus and added diazotrophs. Root colonization by soil indigenous arbuscular mycorrhizal fungi declined in all inoculated plants compared to control. Non-metric multidimensional scaling (NMDS) analysis of the bacterial 16S rRNA gene amplicons revealed that the FM fungus modified the soil microbiome. Our in vitro study indicated that A. occidentalis could not grow on substrates containing lignocellulosic materials or sucrose, but grew on media supplemented with hexoses such as glucose and fructose, indicating that the FM fungus has limited saprotrophic capacity similar to ectomycorrhizal fungi. The results revealed synergistic interactions between A. occidentalis and soil free-living diazotrophs, indicating a potential to boost microbial N2 fixation for non-legume crops
A fuzzy system with common linear-term consequents equivalent to FLNN and GMM
No full textIn this study, a novel Takagi–Sugeno–Kang (TSK) fuzzy system termed as CLT–TSK in which the consequent of each fuzzy rule owns a common linear term is exploited to demonstrate its four distinctive merits. They are: (1) since much less parameters are involved, CLT–TSK has enhanced interpretability. (2) As an extensively used computational intelligence tool, a slightly changed function-link neural network (FLNN) is provably equivalent to CLT–TSK. As a result, FLNN is actually revisited with the first attempt from the philosophy of fuzzy models. (3) With a mild assumption that each component in Gaussian mixture model (GMM) equally contributes to the formulation of GMM in the sense of the effect of the intrinsic structure of training samples in each component on the corresponding label structure, CLT–TSK is theoretically proved to be equivalent to GMM, which actually helps us understand both CLT–TSK and FLNN from a new statistical perspective. (4) The output expression of CLT–TSK is exactly in accordance with the recently-drawn observation that a simple regression should be a basic yet very important component of final prediction models for various data modeling tasks. Owing to the equivalence among CLT–TSK, FLNN and GMM, their respective effective learning methods can be mutually employed from now on, and any new effort in training one model will actually provide a potential new learning method for another among these three models. In particular, with the help of our previous work about the least learning machine, we develop a fast-learning method for CLT–TSK in this study. Experimental results on different kinds of datasets demonstrate the promising classification and runtime performance of CLT–TSK
The ecological roles of golf courses in urban landscapes
Get PDFThe proliferation of urban golf courses accounts for a growing proportion of the urban land area in Australia and other countries. While many suggest that golf courses have an environmentally negative impact, others believe they are important nodes in the network of urban green space and can provide refugial habitat for wildlife. However, research on golf course ecology is in its infancy and this limits development of explicit guidelines for ecologically sound development. Therefore, this PhD research used remote sensing technology to investigate the ecological roles of golf courses in maintenance of vegetation at the urban landscape scale. The thesis explores temporal and spatial landscape data as well as the possible cooling effects golf course can provide in the Perth Metropolitan Region.
The multifunctional aspects of green spaces in golf courses are highlighted in this study. Firstly, by using moderate resolution satellite imagery (Landsat) time series data for three decades from 1988 to 2018 to assess temporal changes in vegetation cover, the study found that vegetation clearance was significant and vegetation cover has become increasingly fragmented. It was concluded that golf courses contribute to urban conservation through the maintenance of vegetation cover and by increasing habitat connectivity during the long period of urbanisation. Secondly, high resolution satellite imagery (PlanetScope (PS) Level 3B) was then used to compare spatially the characteristics of vegetation within golf courses with other urban land-use. It found that golf courses have less conservation values than conservation land, but their role in preservation of native vegetation, vegetation health and habitat connectivity is more significant than other highly intensive urban land-uses. Thirdly, analysis of multispectral high resolution airborne imagery for assessing the capacity of golf courses in mitigating the urban temperature revealed that urban golf courses can provide cooling effects in the urban environment through the provision of tree coverage and other green areas.
Despite limitations of the research being carried out at the landscape scale, the findings of the thesis can enhance the future integration of golf courses into urban biodiversity conservation and ecosystem service improvement
Benefit-cost analysis of a H7N9 vaccination program in poultry in Guangxi, China
No full textChina launched a H7N9 vaccination program in poultry, starting from the Guangxi and Guangdong provinces in July 2017, followed by other provinces in September 2017, as a response to a steep increase of H7N9 influenza human infections from September 2016. Since then, H5-H7 bivalent vaccine has been used in the nationwide avian influenza compulsory vaccination program to replace the existing H5N1 vaccine. However, the economic returns of the H7N9 vaccination program in China have never been adequately assessed. This study was designed to evaluate the economic value of the H7N9 vaccination program in Guangxi by assessing the benefits and costs of the program compared to not vaccinating against H7N9.
A benefit-cost analysis (BCA) was undertaken to evaluate the adoption of a vaccination program against H7N9 in each of three consecutive years from July 2017 to June 2020 with the baseline scenario (the absence of H7N9 vaccination in the 12-month period July 2016 to June 2017). Both animal and public health perspectives were included in the BCA framework and took account of both the private and public sectors.
Benefit-Cost Ratio (BCR) of the three-year H7N9 vaccination program was 18.6 (90 %PI: 15.4; 21.8), and total Net Present Values reached to CNY 1.63 billion (90 %PI: 1.37 billion; 1.89 billion). The extra revenue generated by the yellow broiler industry comprised 93.8 % of the total benefits after adoption of H7N9 vaccination program in Guangxi. While cost-savings in public health and animal health expenditure avoided were 3.6 % and 2.6 %, respectively. Total costs arising from adoption of the revised vaccination program over the three years were CNY 12.46 million (90 %PI: 11.49 million; 14.14 million), CNY 34.87 million (90 %PI: 31.88 million; 40.06 million), and CNY 44.28 million (90 %PI: 39.66 million; 52.27 million), respectively. Sensitivity analysis found the yellow broiler wholesale prices contributed 97.7 % of the variance of the total NPV of three vaccination years. The study results demonstrate the significant economic advantage of implementing a vaccination program against H7N9 in Guangxi. It also offers a new set of evidence to China’s H7N9 vaccination policy and debates around economic values of conducting routine avian influenza vaccination
Integrating gene expression and clinical data to identify drug repurposing candidates for hyperlipidemia and hypertension
Get PDFDiscovering novel uses for existing drugs, through drug repurposing, can reduce the time, costs, and risk of failure associated with new drug development. However, prioritizing drug repurposing candidates for downstream studies remains challenging. Here, we present a high-throughput approach to identify and validate drug repurposing candidates. This approach integrates human gene expression, drug perturbation, and clinical data from publicly available resources. We apply this approach to find drug repurposing candidates for two diseases, hyperlipidemia and hypertension. We screen >21,000 compounds and replicate ten approved drugs. We also identify 25 (seven for hyperlipidemia, eighteen for hypertension) drugs approved for other indications with therapeutic effects on clinically relevant biomarkers. For five of these drugs, the therapeutic effects are replicated in the All of Us Research Program database. We anticipate our approach will enable researchers to integrate multiple publicly available datasets to identify high priority drug repurposing opportunities for human diseases
How clinicians can support women in making decisions about psychopharmacological treatments in pregnancy
No full textEnsuring that women can make fully informed decisions about all aspects of their care in pregnancy is not only required by law in many jurisdictions, but is integral to the provision of respectful and contemporary person-centred health care..
Intralesional bone marrow and superior check desmotomy is superior to conservative treatment of equine superficial digital flexor tendonitis
No full textBackground
Superficial digital flexor tendon (SDFT) injury is common in racehorses and a significant cause of lost training days and wastage in the industry.
Objectives
To compare the post-injury performance of Thoroughbred and Standardbred racehorses diagnosed with SDFT tendonitis treated with intralesional bone marrow and superior check desmotomy or managed conservatively and further to compare this performance with that of uninjured racehorses.
Study design
Retrospective and case-controlled.
Methods
Medical and race records of racehorses treated surgically or managed conservatively for SDFT tendonitis were collated. Signalment, lesion severity and treatment were identified and performance post-injury compared. Performance of the treatment groups was further assessed by comparison with uninjured racehorses matched for age, sex, number of starts pre-injury and randomly selected from the cases' last races.
Results
The study population comprised 114 racehorses divided into surgical (39/114), conservative (38/114) and control groups (37/114). Horses that had surgery were more likely to return to racing than those managed conservatively (OR 4.7 95% CI [1.6-14.3], P = .006). Standardbreds were more likely to return to race compared with Thoroughbreds (OR 4.0 95% CI [1.2-13.3], P = .03). There was no statistically significant difference in the average number of placings, average number of wins and post-injury earnings between the surgically treated and conservatively managed groups (P = .9, P = .9 and P = .7, respectively). The average number of lifetime starts post-injury/post-selection between surgery, conservative and control groups were not statistically significantly different (P = .2). Surgically treated horses had a statistically significantly shorter time to start post-injury compared with the conservative group (P = .04).
Main limitations
The retrospective nature of the study precludes an actual fit as a nonrandomised clinical trial and the nonrandomised nature of the allocation of the treatment groups is biased.
Conclusions
Surgical intervention of superficial digital flexor tendonitis in racehorses suffering flexor tendon injury showed a higher likelihood of return to racing than conservative treatment
The Soga Saga: The Potential of Maclura cochinchinensis (Moraceae) as an Eco–Friendly Dye in Indonesia
No full textThis study focuses on the potential for sustainable use of M. cochinchinensis, a yellow dye used in Javanese soga batik. Prices paid for M. cochinchinensis heartwood at the start of the value–chain (IDR 1,000/kg [USD 0.071/kg]) in West Timor are low, despite depleted wild stocks. Bulk suppliers to the batik industry in Java, however, sell M. cochinchinensis dye–wood at IDR 21,000/kg (USD 1.50/kg), trying to source this heartwood at low prices. Although we estimated 14.12 stems/ha, most (87%) were small stems ( 29 cm BC) stems (0.8 stems/ha [5.5%]). Recruitment of medium and large stems is poor due to browse of small stems by livestock. Wild stocks are unlikely to sustain current commercial demand. Natural mortality rates of this dense (c. 0.8 g/cm3) hardwood species are low, so we also concluded that the option of sustainable harvesting deadwood based on natural mortality rates was not economically viable. The most appropriate ways forward are first, to conserve M. cochinchinensis populations in remnant le’u (“sacred”) forests and maintain “trellis trees” in the surrounding landscape. Second, to promote M. cochinchinensis cultivation along wooden fence lines (bahan). Implementation of “living fences” at a large scale is possible, also improving food security by reducing livestock damage to crops. Third, to develop niche markets paying fair prices for sustainably harvested M. cochinchinensis dye–wood.
Studi ini difokuskan pada potensi pemanfaatan secara berkelanjutan dari M. cochinchinensis, yaitu pewarna kuning yang digunakan pada resep soga oleh pembatik di Jawa. Harga yang dibayarkan kepada pemanen hati kayu M. cochinchinensis yang berada pada rantai pasar paling pertama di Timor Barat tergolong rendah (Rp. 1000 / kg (USD 0,071 / kg), padahal stok liar yang layak panen telah habis. Akan tetapi, penjual grosir untuk industri batik di Jawa menjual hati kayu M. cochinchinensis dengan harga Rp 21.000 / kg (USD 1,50 / kg), padahal mereka membeli dengan harga rendah. Dari kepadatan populasi yang diperkirakan 14,12 batang / ha, sebagian besar (87%) adalah batang kecil ( 29 cm BC) (0,8 batang / ha (5,5%). Tingkat kelangsungan hidup batang berukuran sedang dan besar tidak bagus karena anakan dimakan ternak. Stok liar tidak mungkin bisa menopang permintaan komersial saat ini. Oleh karena tingkat kematian alami dari jenis kayu keras dan padat ini cukup rendah (c. 0.8 g / cm3) kami menyimpulkan bahwa pemanenan kayu mati tidak layak secara ekonomi. Jalan untuk menjaga ketersediaan tumbuhan ini terdiri dari tiga tahap. Pertama, melestarikan populasi M. cochinchinensis di sisa hutan le’u (hutan keramat) dan memelihara “pohon terali” di area sekitarnya. Kedua, mempromosikan pembudidayaan M. cochinchinensis di garis pagar kayu (bahan). Penerapan “pagar hidup” dalam skala besar dimungkinkan, dan akan meningkatkan ketahanan pangan dengan mengurangi kerusakan kebun oleh ternak. Ketiga, mengembangkan pasar khusus yang mau membayar harga yang wajar untuk kayu pewarna M. cochinchinensis yang dipanen secara berkelanjutan
Aerially applied zinc oxide nanoparticle affects reproductive components and seed quality in fully grown bean plants ( Phaseolus vulgaris L.)
Get PDFThe development of reproductive components in plant species is susceptible to environmental stresses. The extensive application of zinc oxide nanoparticles (nZnO) in various agro-industrial processes has jeopardized the performance and functionality of plants. To understand the response of the developmental (gametogenesis and sporogenesis) processes to nanoparticles (NPs) exposure, the aerial application of nZnO and their ionic counterpart of ZnSO4 at four different levels were examined on bean plants (Phaseolus vulgaris) before the flowering stage. To evaluate the mentioned processes, briefly, flowers in multiple sizes were fixed in paraffin, followed by sectioning and optical analysis. The possibility of alteration in reproductive cells was thoroughly analyzed using both light and electron microscopes. Overall, our results revealed the histological defects in male and female reproductive systems of mature plants depend on NPs levels. Furthermore, NPs caused tapetum abnormalities, aberrations in carbohydrate accumulation, and apoptosis. The nZnO induced abnormal alterations right after meiosis and partly hindered the microspore development, leading to infertile pollens. The seed yield and dry weight were reduced to 70 and 82% at 2,000 mg L-1 nZnO foliar exposure, respectively. The sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis pattern showed the increased expression of two proteins at the molecular weight of 28 and 42 kDa at various concentrations of nZnO and ZnSO4. Overall, our results provided novel insights into the negative effect of nano-scaled Zn on the differential mechanism involved in the reproductive stage of the plants compared with salt form