326 research outputs found
Examining sources and pathways of phosphorus transfer in a ditch-drained field
Understanding the processes that mobilize and transport dissolved phosphorus (P) during storms is critical to managing P in flat landscapes with open ditch drainage and legacy soil P. In this study, we used routine baseflow monitoring and intensive storm sampling at a ditch-drained site on Maryland’s Lower Eastern Shore (July 2017–September 2018) to assess whether concentration–discharge (C-Q) relationships and chemical and isotopic hydrograph separation could provide insight into the processes that mobilize and transport dissolved P in ditch drainage. Using a segmented regression model, we determined that long-term C-Q relationships for dissolved P differed above and below a discharge threshold of 6.4 L s–1. Intensive storm sampling revealed that small storms (n = 3) occurring at or below the discharge threshold generally exhibited complex hysteresis and dissolved P dilution patterns that were consistent with deeper (\u3e122 cm) groundwater inputs with low dissolved P concentrations (0.04 mg L–1). In contrast, large storms occurring well above the discharge threshold (n = 4) induced rising water tables and preferential flow pathways that most likely tapped dissolved P–enriched shallow (\u3c20 cm) soil waters (0.89 mg L–1), producing consistent clockwise hysteresis and dissolved P flushing patterns. Notably, chemical and isotope hydrograph separation during two of the largest storms revealed significant event water fractions (59–68%) that strongly suggested a role for the rapid delivery of dissolved P via preferential flow pathways. Findings highlight the need to mitigate vertical P stratification as a means for reducing dissolved P flushing from ditch-drained landscapes with legacy P
Impact of small-scale irrigation schemes on household income and the likelihood of poverty in the Lake Tana basin of Ethiopia
This study uses Tobit and Logit models to examine the impacts of selected small-scale irrigation schemes in the Lake Tana basin of Ethiopia on household income and the likelihood of poverty, respectively. Data for these analyses were collected from a sample of 180 households. Households using any of the four irrigation systems had statistically significantly higher mean total gross household income than households not using irrigation. The marginal impact of small-scale irrigation on gross household income indicated that each small scale-irrigation user increased mean annual household income by ETB 3353 per year, a 27% increase over income for non-irrigating households. A Logit regression model indicated that access to irrigation significantly reduced the odds that a household would be in the lowest quartile of household income, the poverty threshold used in this study. Households using concrete canal river diversion had higher mean cropping income per household than those using other irrigation types. Key challenges to further enhancing the benefits of irrigation in the region include water seepage, equity of water distribution, availability of irrigation equipment, marketing of irrigated crops and crop diseases facilitated by irrigation practices
Identification of phosphorus index improvements through model comparisons across topographic regions in a small agricultural watershed in Vermont
Many U.S. states require farmers to evaluate the risk of P loss from farm fields using P site assessment tools, such as the Phosphorus Index (P-Index). The simplicity of the P-Index allows for users with various backgrounds to utilize the tool; however, the P-Index may be limited in its ability to reliably predict P losses across variable farm terrain, for instance where saturation-excess runoff generation dominates. The objective of this study was to identify potential improvements that could be made to the Vermont P-Index (VT P-Index) by comparing VT P-Index predictions of P loss with those of a model that considers topographic controls on P transport. Scenarios with varying P management strategies were developed and modeled for corn (Zea mays L.) silage production fields in a small agricultural watershed (360 ha) located in Vermont using both the VT P-Index and a modified version of the Soil and Water Assessment Tool (SWAT). Modeled outputs from both the VT P-Index and SWAT were aggregated based on topographic index (TI) class and compared for the directional agreement of P risk assessments and relative annual average dissolved and particulate P losses. The P-Index nutrient management recommendations gave higher P loss risk ratings than SWAT for 94% of the 120 unique scenario combinations simulated. Results from this study suggest that the VT P-Index could improve its ability to support farm nutrient management planning by incorporating topographic controls on runoff production into its estimation of P transport
Factors in the suboptimum performance of rural water supply systems in the Ethiopian highlands
Access to safe drinking water services in the Ethiopian Highlands is one of lowest worldwide due to failure of water supply services shortly after construction. Over hundred water supply systems were surveyed to find the underlying causes of failure and poor performance throughout the Amhara Regional State. The results show generally that systems with decision-making power at the community level during design and construction remained working longer than when the decisions were made by a central authority. In addition, the sustainability was better for water systems that were farther away from alternative water resources and contributed more cash and labour. The results of this study of the importance of decision-making at the local level in contrast to the central authority is directly applicable to the introduction of rain water management systems as shown by earlier efforts of installing rain water harvesting systems in the Ethiopian highlands
On the radiative decays of light vector and axial-vector mesons
We study the light vector and axial-vector mesons. According to the
hadrogenesis conjecture the nature of the two types of states is distinct. The
axial-vector mesons are generated dynamically by coupled-channel interactions
based on the chiral Lagrangian written down in terms of the Goldstone bosons
and the light vector mesons. We propose a novel counting scheme that arises if
the chiral Lagrangian is supplemented by constraints from large-N_c QCD in the
context of the hadrogenesis conjecture. The counting scheme is successfully
tested by a systematic study of the properties of vector mesons. The spectrum
of light axial-vector mesons is derived relying on the leading order
interaction of the Goldstone bosons with the vector mesons supplemented by a
phenomenology for correction terms. The f_1(1282), b_1(1230), h_1(1386),
a_1(1230) and K_1(1272) mesons are recovered as molecular states. Based on
those results the one-loop contributions to the electromagnetic decay
amplitudes of axial-vector molecules into pseudo-scalar or vector mesons are
evaluated systematically. In order to arrive at gauge invariant results in a
transparent manner we choose to represent the vector particles by
anti-symmetric tensor fields. It is emphasized that there are no tree-level
contributions to a radiative decay amplitude of a given state if that state is
generated by coupled-channel dynamics. The inclusion of the latter would be
double counting. At present we restrict ourselves to loops where a vector and a
pseudo-scalar meson couple to the axial-vector molecule. We argue that final
and predictive results require further computations involving intermediate
states with two vector mesons. The relevance of the latter is predicted by our
counting rules.Comment: added appendix concerning double-counting issue
Estimation of evaporation over the upper Blue Nile basin by combining observations from satellites and river flow gauges
Reliable estimates of regional evapotranspiration are necessary to improve water resources management and planning. However, direct measurements of evaporation are expensive and difficult to obtain. Some of the difficulties are illustrated in a comparison of several satellite-based estimates of evapotranspiration for the Upper Blue Nile (UBN) basin in Ethiopia. These estimates disagree both temporally and spatially. All the available data products underestimate evapotranspiration leading to basin-scale mass balance errors on the order of 35 percent of the mean annual rainfall. This paper presents a methodology that combines satellite observations of rainfall, terrestrial water storage as well as river-flow gauge measurements to estimate actual evapotranspiration over the UBN basin. The estimates derived from these inputs are constrained using a one-layer soil water balance and routing model. Our results describe physically consistent long-term spatial and temporal distributions of key hydrologic variables, including rainfall, evapotranspiration, and river-flow. We estimate an annual evapotranspiration over the UBN basin of about 2.55 mm per day. Spatial and temporal evapotranspiration trends are revealed by dividing the basin into smaller subbasins. The methodology described here is applicable to other basins with limited observational coverage that are facing similar future challenges of water scarcity and climate change
Evaluation of CFSR, TMPA 3B42 and ground-based rainfall data as input for hydrological models, in data-scarce regions: The upper Blue Nile Basin, Ethiopia
Accurate prediction of hydrological models requires accurate spatial and temporal distribution of rainfall. In developing countries, the network of observation stations for rainfall is sparse and unevenly distributed. Satellite-based products have the potential to overcome this shortcoming. The objective of this study is to compare the advantages and the limitation of commonly used high-resolution satellite rainfall products (Climate Forecast System Reanalysis (CFSR) and Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) 3B42 version 7) as input to hydrological models as compared to sparsely and densely populated network of rain gauges. We used two (semi-distributed) hydrological models that performed well in the Ethiopian highlands: Hydrologiska Byråns Vattenbalansavdelning (HBV) and Parameter Efficient Distributed (PED). The rainfall products were tested in two watersheds: Gilgel Abay with a relatively dense network of rain gauge stations and Main Beles with a relatively scarce network, both are located in the Upper Blue Nile Basin. The results indicated that TMPA 3B42 was not be able to capture the gauged rainfall temporal variation in both watersheds and was not tested further. CFSR over predicted the rainfall pattern slightly. Both the gauged and the CFSR reanalysis data were able to reproduce the streamflow well for both models and both watershed when calibrated separately to the discharge data. Using the calibrated model parameters of gauged rainfall dataset together with the CFSR rainfall, the stream discharge for the Gilgel Abay was reproduced well but the discharge of the Main Beles was captured poorly partly because of the poor accuracy of the gauged rainfall dataset with none of the rainfall stations located inside the watershed. HBV model performed slightly better than the PED model, but the parameter values of the PED could be identified with the features of the landscape
Combining Essential Oils of Piper betle and Myristica fragrans for Enhanced Antimicrobial Properties
This paper reports the chemical compositions and antimicrobial activity of essential oils extracted fromMyristica fragrans and Piper betle in individual and combined fractions. Enhanced antimicrobial activity isanticipated when the volatile oils are combined as compounds present in different extracts could complementeach other resulting in synergistic effect offering a broader spectrum of microbial resistance. The GC-MSanalysis indicates that chemical compositions of M. fragrans and P. betle vary with M. fragrans containingmore early-eluting compounds. The combined extract is characterised by compounds present in both extracts,some appear to co-elute in the mixture. The antimicrobial activity of the single and combined extracts againstStaphylococcus aureus, Escherichia coli and Aspergillus flavus were evaluated. P. betle demonstrates strongerantimicrobial activity than M. fragrans; the combined extract exhibit improved performance especially on A.flavus
Advanced Cyber and Physical Situation Awareness in Urban Smart Spaces
The ever-growing adoption of big data technologies, smart sensing,
data science and artificial intelligence is enabling the development of new intelligent urban spaces with real-time monitoring and advanced cyber-physical situational awareness capabilities. In the S4AllCities international research project, the advancement of cyber-physical situational awareness will be experimented for achieving safer smart city spaces in Europe and beyond. The deployment of digital twins will lead to understanding real-time situation awareness and risks of potential physical and/or cyber-attacks on urban critical infrastructure specifically. The critical extraction of knowledge using digital twins, which ingest, process and fuse observation data and information, prior to machine reasoning is performed in S4AllCities. In this paper, a cyber behavior detection module, which identifies unusualness in cyber traffic networks is described. Also, a physical behaviour detection module is introduced. The two modules function within the so-called Malicious Attacks Information Detection System (MAIDS) digital
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Evaluation of Cutting Sizes and Sticking Cutting Times on Propagation of Rosemary
Rosemary (Rosmarinus officinalis) is a well-known culinary and medicinal herb in the Lamiaceae family, which is native to the Mediterranean area. It is a source of antioxidants and has several benefits for the body\u27s health, such as antiinflammatory, anti-fungal activity, anti-aging, and support of the digestive system. Rosemary has several habit types: trailing, creeping, and upright; its flowers can be blue, violet, pink, or white. It could be propagated by seeds or by vegetative methods. Seedlings can show a high level of genetic diversity; therefore, vegetative propagation is used to keep the mother traits of the cultivars. One of the common vegetative methods used is cuttings. A study was conducted to evaluate the ability of different sizes of cuttings to determine the best time for sticking cuttings. This experiment was done on a raised bed in a greenhouse at Morehead State University, Derrickson Agricultural Complex, in 2024. The rosemary was propagated at four different cutting sizes, including 50, 100, 150, and 200 mm, at two different times, September 18th and October 9th. All cuttings were treated with Auxin and inserted in the media (Pro-mix BX- mycorrhizae). Cuttings were evaluated after 45 days for their rooting formation. The roots were measured, and the data was collected and analyzed. The primary results show differences in cutting size and sticking times. The best rooting results were observed when 100 mm cuttings were taken on October 9, 2024. This project is still ongoing and in the second season with new cuttings.https://scholarworks.moreheadstate.edu/celebration_posters_2025/1084/thumbnail.jp
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