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Attitudes of Fruit and Vegetable Farmers towards Organic Farming in Kathmandu Valley, Nepal
Get PDFOrganic farming is increasingly popular among the farmers of Kathmandu valley. However, the organic growers have been facing issues in production, organic certification, and product marketing. To date, little is known about the challenges faced by the organic growers in Kathmandu valley. This study aimed to explore the status of organic farming, attitudes of farmers towards organic farming, their suggestions for improvement, and strengthening the value chain of organic products. Face-to-face interviews were conducted at Agriculture Knowledge Centre, Lalitpur, Nepal during December 2019 with 37 organic growers directly or indirectly involved in organic farming. The results showed that organic growers face challenges in marketing and institutional recognition. Challenges in product certification and marketing were reported by 45.95% of the total interviewed organic growers while following organic practices (transitional organic). Our study suggested that reducing the cost of production through easy access to organic inputs like organic seeds, fertilizers, and biopesticides are highly desired by the growers. Participatory Guarantee System (PGS) or group certification along with collective marketing could be the policy implications to address the issues. Organic farming in Kathmandu valley is limited to a niche market; however, due to increasing consumer demand for safe, fresh, and local food, the popularity of organic products is extending to other regions within the country
Organic and conventional sweetpotato production in the Southeastern of United States: a comparative analysis
Get PDFBackground
There has been a piqued interest in alternative agricultural production systems that are environmentally friendly due to concerns on how sustainable it is to grow conventionally. However, in the producer’s point of view, economic returns are an important issue in decision-making in adaptation. The purpose of this study is to assess the economic risk of conventional and organic sweetpotato production in the Southeastern US. The primary and secondary data were used for the analysis. We identified risk variables in stochastic profit function and performed Monte Carlo simulation in analyzing profitability and economic risk of conventional and organic production systems. Results
Findings from the meta-analysis suggest lower sweetpotato yields and higher selling prices, are to be expected in the organic sweetpotato production systems compared with the conventional. A higher probability of having positive net return from organically grown sweetpotato compared to conventional production systems was observed. Conclusions
Increase in unit cost leads to a decrease in net profit in both conventional and organic production systems. Sweetpotato price has more effect on net return compared to its yield in conventional production systems. The higher selling price, lower yield and lower unit costs provide a higher net profit return for the organic sweetpotato production systems. Unit cost in conventional production was noted to be higher in general, inferring conventional sweetpotato production could potentially experience a higher variability in net farm income. Despite the high production cost, however, farmers are encouraged to go into sweetpotato production as it appears to be profitable. Further studies should be conducted on conventional treatments without synthetic pesticides and fertilizers as these systems perhaps, may display lower external input costs that might make them more profitable similar to organic systems
A Research Road Map for Responsible Use of Agricultural Nitrogen
Get PDFNitrogen (N) is an essential but generally limiting nutrient for biological systems. Development of the Haber-Bosch industrial process for ammonia synthesis helped to relieve N limitation of agricultural production, fueling the Green Revolution and reducing hunger. However, the massive use of industrial N fertilizer has doubled the N moving through the global N cycle with dramatic environmental consequences that threaten planetary health. Thus, there is an urgent need to reduce losses of reactive N from agriculture, while ensuring sufficient N inputs for food security. Here we review current knowledge related to N use efficiency (NUE) in agriculture and identify research opportunities in the areas of agronomy, plant breeding, biological N fixation (BNF), soil N cycling, and modeling to achieve responsible, sustainable use of N in agriculture. Amongst these opportunities, improved agricultural practices that synchronize crop N demand with soil N availability are low-hanging fruit. Crop breeding that targets root and shoot physiological processes will likely increase N uptake and utilization of soil N, while breeding for BNF effectiveness in legumes will enhance overall system NUE. Likewise, engineering of novel N-fixing symbioses in non-legumes could reduce the need for chemical fertilizers in agroecosystems but is a much longer-term goal. The use of simulation modeling to conceptualize the complex, interwoven processes that affect agroecosystem NUE, along with multi-objective optimization, will also accelerate NUE gains
Recent advances toward the sustainable management of invasive Xylosandrus ambrosia beetles
Get PDFWe provide an overview of both traditional and innovative control tools for management of three Xylosandrus ambrosia beetles (Coleoptera: Curculionidae: Scolytinae), invasive species with a history of damage in forests, nurseries, orchards and urban areas. Xylosandrus compactus, X. crassiusculus and X. germanus are native to Asia, and currently established in several countries around the globe. Adult females bore galleries into the plant xylem inoculating mutualistic ambrosia fungi that serve as food source for the developing progeny. Tunneling activity results in chewed wood extrusion from entry holes, sap outflow, foliage wilting followed by canopy dieback, and branch and trunk necrosis. Maintaining plant health by reducing physiological stress is the first recommendation for long-term control. Baited traps, ethanol-treated bolts, trap logs and trap trees of selected species can be used to monitor Xylosandrus species. Conventional pest control methods are mostly ineffective against Xylosandrus beetles because of the pests’ broad host range and rapid spread. Due to challenges with conventional control, more innovative control approaches are being tested, such as the optimization of the push–pull strategy based on specific attractant and repellent combinations, or the use of insecticide-treated netting. Biological control based on the release of entomopathogenic and mycoparasitic fungi, as well as the use of antagonistic bacteria, has yielded promising results. However, these technologies still require validation in real field conditions. Overall, we suggest that management efforts should primarily focus on reducing plant stress and potentially be combined with a multi-faceted approach for controlling Xylosandrus damage
Sex differences in weight perception and weight gain among Black college students in the USA
Get PDFObjectives The aims of this study were to examine the prevalence of overweight/obesity and to explore sex differences in body weight perceptions and correlates of weight gain among Black students at 2 historically Black colleges and universities (HBCUs) in the USA. Methods Participants completed a paper-based survey, and their height and weight were measured (67% completion rate). Results The overweight and obesity rates were 33.8% and 26.9%, respectively. More females than males accurately assessed their weight (p\u3c0.05). Body weight underestimation was associated with male sex, excellent/very good perceived overall health, and not being informed by a doctor of having overweight or obesity (p\u3c0.01). Higher odds of ≥5% weight gain were related to female sex, living on campus, and not being informed by a doctor of having overweight or obesity (p\u3c0.05). Conclusion Given the high overweight and obesity rates among Black students, HBCUs in the USA should develop intervention strategies for the prevention and management of overweight and obesity. College health educators at HBCUs need to provide regular check-ups or health screenings that help male students perceive their weight accurately and prevent weight underestimation. It is important for HBCUs to monitor and address weight gain among Black students as early as possible
Epigenetic Evolution of ACE2 and IL-6 Genes: Non-Canonical Interferon-Stimulated Genes Correlate to COVID-19 Susceptibility in Vertebrates
Get PDFThe current novel coronavirus disease (COVID-19) has spread globally within a matter of months. The virus establishes a success in balancing its deadliness and contagiousness, and causes substantial differences in susceptibility and disease progression in people of different ages, genders and pre-existing comorbidities. These host factors are subjected to epigenetic regulation; therefore, relevant analyses on some key genes underlying COVID-19 pathogenesis were performed to longitudinally decipher their epigenetic correlation to COVID-19 susceptibility. The genes of host angiotensin-converting enzyme 2 (ACE2, as the major virus receptor) and interleukin (IL)-6 (a key immuno-pathological factor triggering cytokine storm) were shown to evince active epigenetic evolution via histone modification and cis/trans-factors interaction across different vertebrate species. Extensive analyses revealed that ACE2 ad IL-6 genes are among a subset of non-canonical interferon-stimulated genes (non-ISGs), which have been designated for their unconventional responses to interferons (IFNs) and inflammatory stimuli through an epigenetic cascade. Furthermore, significantly higher positive histone modification markers and position weight matrix (PWM) scores of key cis-elements corresponding to inflammatory and IFN signaling, were discovered in both ACE2 and IL6 gene promoters across representative COVID-19-susceptible species compared to unsusceptible ones. The findings characterize ACE2 and IL-6 genes as non-ISGs that respond differently to inflammatory and IFN signaling from the canonical ISGs. The epigenetic properties ACE2 and IL-6 genes may serve as biomarkers to longitudinally predict COVID-19 susceptibility in vertebrates and partially explain COVID-19 inequality in people of different subgroups
The California Legacy Survey. I. A Catalog of 178 Planets from Precision Radial Velocity Monitoring of 719 Nearby Stars over Three Decades
Get PDFWe present a high-precision radial velocity (RV) survey of 719 FGKM stars, which host 164 known exoplanets and 14 newly discovered or revised exoplanets and substellar companions. This catalog updated the orbital parameters of known exoplanets and long-period candidates, some of which have decades-longer observational baselines than they did upon initial detection. The newly discovered exoplanets range from warm sub-Neptunes and super-Earths to cold gas giants. We present the catalog sample selection criteria, as well as over 100,000 RV measurements, which come from the Keck-HIRES, APF-Levy, and Lick-Hamilton spectrographs. We introduce the new RV search pipeline RVSearch (https://california-planet-search.github.io/rvsearch/) that we used to generate our planet catalog, and we make it available to the public as an open-source Python package. This paper is the first study in a planned series that will measure exoplanet occurrence rates and compare exoplanet populations, including studies of giant planet occurrence beyond the water ice line, and eccentricity distributions to explore giant planet formation pathways. We have made public all radial velocities and associated data that we use in this catalog
High-Fat Diet-Induced Obese Effects of Adipocyte-Specific CXCR2 Conditional Knockout in the Peritoneal Tumor Microenvironment of Ovarian Cancer
Get PDFObesity contributes to ovarian cancer (OC) progression via tumorigenic chemokines. Adipocytes and OC cells highly express CXCR2, and its ligands CXCL1/8, respectively, indicating that the CXCL1/8-CXCR2 axis is a molecular link between obesity and OC. Here, we investigated how the adipocyte-specific CXCR2 conditional knockout (cKO) affected the peritoneal tumor microenvironment of OC in a high-fat diet (HFD)-induced obese mouse model. We first generated adipocyte-specific CXCR2 cKO in mice: adipose tissues were not different in crown-like structures and adipocyte size between the wild-type (WT) and cKO mice but expressed lower levels of CCL2/6 compared to the obese WT mice. HFD-induced obese mice had a shorter survival time than lean mice. Particularly, obese WT and cKO mice developed higher tumors and ascites burdens, respectively. The ascites from the obese cKO mice showed increased vacuole clumps but decreased the floating tumor burden, tumor-attached macrophages, triglyceride, free fatty acid, CCL2, and TNF levels compared to obese WT mice. A tumor analysis revealed that obese cKO mice attenuated inflammatory areas, PCNA, and F4/80 compared to obese WT mice, indicating a reduced tumor burden, and there were positive relationships between the ascites and tumor parameters. Taken together, the adipocyte-specific CXCR2 cKO was associated with obesity-induced ascites despite a reduced tumor burden, likely altering the peritoneal tumor microenvironment of OC
The Impact of Community Cultural Wealth on Resilience, Student Engagement and Academic Success: An Ethnographic Study of Two Historically Black Colleges and Universities
No full textCurrent research on resilience and academic success is plentiful in higher education. The academic discourse on HBCU’s impacts to higher education also abound. However, there is little space in academia dedicated to recognizing that examines the unique HBCU landscape and its impact on high needs areas in higher education. This study investigated the way that Yosso’s Community Cultural Wealth Framework is used by HBCUs to support student success. The findings indicate that the two HBCUs studied use a web of the six tenets within the Community Cultural Capital Wealth