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Dissimilarity between Andropogon lateralis ecotypes under different defoliation frequencies and heights
Get PDFAndropogon lateralis Nees is a native grass of southern Brazil and is one of the most frequent specie found in native grasslands. The species is widely distributed and has a high degree of phenotypic plasticity, which makes it highly adaptable to different edaphoclimatic conditions and management. This study aimed to evaluate the behavior of twelve ecotypes of A. lateralis, collected in different regions of the state of Rio Grande do Sul and cut to three different heights and subjected to two different defoliation frequencies. From September to February, the ecotypes were evaluated for total dry matter, leaf and stem yields. In addition, total, vegetative and reproductive tillers and plant height were measured. These characteristics are important for the selection of superior genotypes in terms of genetic variability and forage production. Total dry matter and leaf dry matter are characteristics with agronomic importance and they showed the highest correlation (r = 0.77), enabling an indirect selection for one of these characteristics. The natural selection of plants resulted in distinct structural, morphological and productive characteristics with heterogeneity that allows the selection and grouping according to the characteristics, ecotypes with superior agronomic characteristics can be included in breeding programs
Isolation and characterisation of monoclonal picocyanobacterial strains from contrasting New Zealand lakes
No full textFreshwater picocyanobacteria form the base of microbial food webs in many lakes worldwide but have received less attention than other phytoplankton. Little is known about their potential response to environmental changes such as increased nutrient loading and climate change, due partly to the lack of available cultured and sequenced strains. Here, we isolated 25 monoclonal picocyanobacterial strains from 6 New Zealand lakes with contrasting trophic states. The use of MLA medium instead of BG11 proved highly successful for the rapid isolation of picocyanobacteria. Strains were characterised by sequencing of the 16S ribosomal RNA gene, spectrophotometry, and high-performance liquid chromatography. 16S rRNA gene analysis placed most strains within the cluster 5 picocyanobacterial lineage (sub-cluster 5.2, family: Synechococcaceae). Phylogenetic analysis showed that 12 isolates from Lakes Wakatipu, Hayes, Johnson, and Ellesmere/Te Waihora clustered with strains from a range of Northern Hemisphere locations, suggesting global dispersal of these strains. Pigment characterisation revealed that pink and brown cultures from oligotrophic and some eutrophic lakes were rich in phycoerythrin, while green cultures from eutrophic and hypertrophic lakes were rich in phycocyanin. This diverse group of freshwater cluster 5 picocyanobacterial cultures will provide a new resource to study how these critically important microbes function and respond to changing environmental stressors
Off-farm work and technical efficiency of wheat production in China
No full textThe present study examined the effect of off-farm work on the technical efficiency (TE) of wheat production, using data collected from farming households in China. We mainly explored four dimensions of off-farm work, including the household heads’ off-farm work participation, local off-farm work participation, migrated off-farm work participation, and off-farm work intensity. To further our understanding, we also measured off-farm work variables at the household level (i.e., number and ratio of off-farm workers in a household and off-farm income) and estimated their impacts on TE. A stochastic production frontier model was used to estimate the TE of wheat production. Given that off-farm work variables are potentially endogenous due to self-selection issues, we employed a two-stage residual inclusion (2SRI) approach to address such endogeneity problems. The findings from our study revealed that off-farm work participation of household heads exerted a positive and significant impact on TE. Local off-farm work participation showed a significant positive effect on TE but migrated off-farm work participation did not indicate any significant effect on TE. Although off-farm work intensity does not show a significant impact on TE, further analysis using intensity dummies suggested that off-farm work intensity tends to increase TE of wheat production when household heads work off-farm between 9 and 12 months. Additional analysis suggested that a higher TE of wheat production is not necessarily associated with the number and ratio of off-farm workers in a household and off-farm income. Generally, our research has supported the positive impact of off-farm work on TE of crop production from multiple dimensions. We found that TE is positively and significantly influenced by the household heads’ age, health status, and farm size but negatively and significantly affected by distance to the market. Our findings underscore that off-farm work participation is a critical pathway for smallholder farmers to boost efficient farm production. From the perspective of promoting production efficiency, our research shows that it is essential to encourage household heads to participate in off-farm work locally, especially those unable to migrate due to household responsibilities. Therefore, the policy aiming to achieve efficient production should consider cultivating and developing industries with local characteristics, which can help create more off-farm work opportunities. Disseminating local off-farm work information via accessible channels, such as radios or message services of smartphones, and providing job-seeking subsidies might make a difference in encouraging household heads’ off-farm work participation. Farmers’ health status is positively associated with a higher TE. The finding underscores the importance of saturating health knowledge among rural farmers to improve their health levels and human capital
Snail meat consumption in Buea-Cameroon: Exposures to foodborne pathogens through social practices assessed in 2019 and 2021
No full textBackground: Snail meat is an important source of nutrition in Cameroon, but the food safety risks are poorly understood. We characterized public health risks from snail meat consumption as a social system in Cameroon, by examining local snail practices that expose snail meat handlers and consumers to foodborne pathogens. Methods: We used exploratory qualitative approaches, that is, lived experience, face-to-face in-depth interviews, participant observation and a focus group, to explore fifteen key informants’ routines and lived experiences, and perceptions of two health officials on the food safety practices around snail meat consumption in Cameroon. This information was organized and interpreted using Soft Systems Methodology and Social Practice Theory, which permitted a systemic appreciation of local practices. Results: We distinguished five kinds of actors (snail vendors, market sellers, street vendors, street eaters and home consumers), who performed seven successive practices (picking, selling, cracking, washing, cooking, hawking and eating). We then identified three worldviews about snails: family support or to reduce poverty, a source of nutrition and a food choice (taste, preference). Our findings revealed participants’ competences were based on childhood learning and ‘inborn’ experiences, and materials used in snail activities reflected participants’ parentage and ‘state of poverty’. Although most interviewees highlighted ‘unhygienic conditions’ when explaining snail picking locations, participants believed washing and cooking should kill all contaminants. Conclusion: Several opportunities for human exposures to foodborne pathogens including snail picking in domestic wastes and sewage, the selling of unpackaged live snails, improper snail meat washing and hawking in loosely closed buckets, were apparent from our analysis. These findings suggest fruitful opportunities aimed at improving health outcomes among African snail meat handlers and consumers
The future of monuments
No full textToday, many want to pull down memorials as expressions of bad politics, especially those memorials that legitimise evil and injustice. What memorials need to go what can stay? Are their 'good' memorials—and who decides? Can we make use of 'bad' memorials? Is the form of the memorial itself now compromised? How do we understand miscellaneous contemporary memorial projects, like Peter Eisenman's Memorial to the Murdered Jews of Europe in Berlin and Ground Zero in New York, or Weta and Te Papa's The Scale of War and Peter Jackson 'colourising' World War I footage? Do memorials have a role moving forward? What form could future memorials take
Nitrogen effects on species’ contributions to grazed pasture mixtures under nitrogen loss and application restrictions
Get PDFNew regulations for the use of N fertiliser will impact on seed mixture decisions for new pastures. To help inform these decisions, effects of N on species and their interactions in pasture mixtures were examined. Ten mixtures of perennial ryegrass (PR), white clover (WC) and plantain (P) were sown on 31 March 2017 and grown ±N fertiliser (275 kg/ha in Year 1 reduced to 200 kg N/ha/year) under grazed and irrigated conditions. After 4 years, an equi-proportional mixture of PR and WC, based on seed count and equivalent to 12 kg PR and 7 kg WC (coated seed)/ha, produced an optimal balance of increased total yield (20.5 t DM/ha/year), weed suppression (4% of total yield), metabolisable energy (11 MJ/kg DM) and crude protein (21%), regardless of N level. Pasture yield and quality responded to change in species proportions away from the optimal mixture, including the addition of P. The magnitude of the yield response was greater with rather than without N fertiliser, because the identity effects of PR and P, and the way all three species interacted, depended on N level. The optimal mixture without N fertiliser produced as much high-quality feed as mixtures with N fertiliser
3D QSAR and pharmacophore studies on inhibitors of insuline like growth factor 1 receptor (IGF-1R) and insulin receptor (IR) as potential anti-cancer agents
Get PDFInsulin like growth factor receptor (IGF-1R) and Insulin receptor (IR) are widely accepted to play a prominent role in cancer drug discovery due to their well-established involvement in various stages of tumorigenesis. Previously, neutralization of IGF-1R via monoclonal antibodies was in focus, which failed because of compensatory activation of IR-A upon inhibition of IGF-1R. Recent studies have demonstrated high homology between IGF-IR and IR particularly in tyrosine kinase domain and targeting both receptors have produced efficient therapeutic approaches such as inhibition of cancer cell cycle proliferation. Herein, we have made an attempt to analyze the unique data set from different chemical classes, containing potent ATP competitors against tyrosine kinase domain. We performed the 2D, 3D quantitative structure–activity relationship (QSAR) studies on inhibitors of these receptors to predict useful pharmacophoric features. We have optimized virtual screening of structurally diverse data set of dual inhibitors of IGF-1R and IR. Based on QSAR studies, we predict potential novel clinical candidates with a demonstrated absorption, distribution, metabolism, elimination, and toxicology (ADMETox) track. We also demonstrated comprehensive analysis of co–crystal complexes along with their inhibitors and built 3D- GRid INdependent Descriptors (GRIND) model to obtain insightful features such as H-bond donors and acceptors, overall topology and Vander Waal volume (vdw_vol) which are found to be responsible for dual inhibition of receptors. These findings lead to further description that Tirofiban, Practolol, Edoxaban, Novobiocin have potential to perform dual inhibition of both targets
Defaunation by deoxygenation: Efficacy and divergent responses of estuarine macroinvertebrates
No full textUnderstanding the influence of macroinvertebrates on ecosystem function often relies on experimental defaunation with methods that remove fauna through minimal sample disturbance. Defaunation is challenging and can lead to confounding effects and/or loss of empirical information when unsuccessful. We evaluated the ability of a deoxygenation treatment to remove macroinvertebrates from sediment cores collected in 2 regions of a microtidal estuary. Only 1 of 16 cores was fully defaunated following 3 deoxygenation cycles. To counteract confounding effects of partial defaunation, we quantified the biomass remaining in each core and used these data as a covariate in statistical models. The unremoved biomass had, in some cases, significant effects on alkalinity fluxes, with positive linear relationships evident, and net phosphate fluxes. The community in the upper estuary that regularly experiences hypoxia exhibited stronger sediment emergence responses (82−100%). The remaining fauna were spread equally among annelids, molluscs and arthropods in abundance, although arthropods dominated the biomass. In contrast, fewer macroinvertebrates emerged from sediments from the lower estuary (47−89%), with most of the remaining biomass and abundance being annelids and molluscs. These findings suggest that estuarine taxa have divergent responses to hypoxia and that regional communities are variably prone to eradication of sensitive taxa. Our study shows how the use of defaunation by deoxygenation can create systematic bias, particularly when comparing areas with disparate in situ oxygen regimes, and provides a way to quantitively account for partial defaunation without sacrificing statistical power or using overly destructive methods
Profiling the tackle and its injury characteristics in premier New Zealand club rugby union players over a complete season
No full textObjectives: RugbySmart is a safe tackle technique education programme. Our objective was to identify whether the RugbySmart-recommended safe tackle technique was exhibited by club rugby players and whether tackle-related injuries showed poor tackle technique characteristics.
Methods: The prospective cohort design enabled 28 senior club based amateur male rugby union players from New Zealand to be followed over 18 matches in the 2017 rugby season. Game video analysis by three analysts provided categorisation of tackle technique into type, approach, foot contact, leading foot and rear foot position, face and head position. Injuries were diagnosed by the same sports medicine physician.
Results: In the 18 matches, 28 players completed a combined total of 3006 tackles, with only six tackle-related injuries sustained. Notable findings included: (1) forwards complete more tackles than backs; (2) shoulder tackles were the most prevalent tackle; (3) good tackle technique as promoted by RugbySmart was demonstrated in 57.9% of all tackles and (4) of the six tackle-related injuries, two occurred despite RugbySmart desired tackle techniques.
Conclusion: This is the first study to investigate whether players were performing the recommended ‘safe tackle technique’ proposed by New Zealand Rugby’s RugbySmart programme. As two of six tackle-related injuries occurred despite the RugbySmart preferred technique being performed, further technique analysis and a larger sample are needed to determine what techniques reduce risk of injury during tackles. As only 57.9% of tackles were performed with RugbySmart head and foot positions, further research and education regarding tackle technique recommendations are needed
Multi-market credit rationing: The determinants of and impacts on farm performance in Vietnam
No full textVietnamese farm households have been suffering to a large extent from credit rationing that potentially impairs agricultural performance. Using primary data from a farm household survey in the Red River Delta region, we investigate the factors affecting agricultural credit rationing in Vietnam's formal, semi-formal, and informal credit markets and how severely credit rationing in each market affects agricultural performance. The trivariate probit model's results reveal that human, social, and physical capital factors help farm households ease credit rationing. A bad credit history and time to travel to credit sources increase farm households’ likelihood of being credit rationed. Credit rationing determinants vary among different credit markets implying segmentation of credit markets for agriculture. We adopt a multinomial endogenous treatment effects model to evaluate credit rationing's impact on farm performance and find that credit rationing in any credit market has a severe, negative impact on agricultural outcomes for farm households. The study provides practical suggestions for policymakers and farm households to reduce credit rationing and boost the agricultural performance in Vietnam