61 research outputs found
Access to AgriculturalInputs, Technology and Information, Communicating with Farmers,and the Role of Women in Agriculture: Perceptions of Iraqi Extension Agents
The goal of this study was to gain a more comprehensive understanding ofaccess to inputs,technology and information available toIraqi extension agents,and to ascertain current farmercommunication strategies and gender roles within the diverse Iraq agricultural extension system.The conflicts, government policies, and economic sanctions that have enveloped Iraq over thelast several decades have significantly impacted access to agricultural resources. Iraqi extensionpersonnel participating inthe Iraq AgriculturalExtension Revitalization (IAER)programprovided their perspective on the availability of agricultural supplies, technology and relatedinformation. About two-thirds of the extension agents indicated that the flow and availability ofagricultural supplies has become less restricted and generally felt that there was greater accessto basic agricultural information compared to the previous decade. Despite perceivingnoticeable improvement overall in access to agricultural supplies and technology, over 83% ofthe program attendees agreed that access to agricultural inputs was currently insufficient tosuccessfully promote productive agricultural practices. An overwhelming preference for face-to-face communication by both farmers and extension personnel also limits the extent to whichagricultural information can be disseminated. In addition, several regional and gender-baseddifferences emerged.Notably, it appears that farmers donot approachfemaleextensionpersonnel equally, wherein better educated farmers are more likely to interact with femaleextensionagents.We suggest that an approach based on a horizontal exchange of knowledgebetween extension personnel and local farmers, coupled with a better integration of womenextension personnel, will help a revitalized Iraqi extension system achieve greater agriculturalsustainabilit
Turbidity removal through the application of powdered azadirachta indica (neem) seeds
Various natural products used for water treatment are becoming more popular due to their general safety, eco-friendly sludge production, ease of degradation, cost-effectiveness, and local availability. This research assessed the efficiency of powdered neem (Azadirachta indica) seeds in removing turbidity from the water. Batch experiments determined the optimum coagulant dose, pH level, mixing time, and mixing speed to reduce turbidity from kaolin-based synthetic turbid water. Powdered neem seeds with a pore size of about 0.45 mm were prepared and used in water treatment under optimum conditions. Results showed that a coagulant dose of 3 g of neem seeds/L, 13.2 pH level, 60 mins mixing time at 80 rpm mixing speed could reduce turbidity levels to 35 NTU from 250 NTU (86% removal). Findings suggest that powdered neem seeds can be a potential substitute for conventional chemical coagulants for drinking water treatment
β-Lactams and Florfenicol Antibiotics Remain Bioactive in Soils while Ciprofloxacin, Neomycin, and Tetracycline Are Neutralized
It is generally assumed that antibiotic residues in soils select for antibiotic-resistant bacteria. This assumption was tested by separately adding 10 different antibiotics (≥200 ppm) to three soil-water slurries (silt-loam, sand-loam, and sand; 20% soil [wt/vol]) and incubating mixtures for 24 h at room temperature. The antibiotic activity of the resultant supernatant was assessed by culturing a sensitive
Escherichia coli
strain in the filter-sterilized supernatant augmented with Luria-Bertani broth. We found striking differences in the abilities of supernatants to suppress growth of the indicator
E. coli
. Ampicillin, cephalothin, cefoxitin, ceftiofur, and florfenicol supernatants completely inhibited growth while bacterial growth was uninhibited in the presence of neomycin, tetracycline, and ciprofloxacin supernatants. High-performance liquid chromatography (HPLC) analysis demonstrated that cefoxitin and florfenicol were almost completely retained in the supernatants, whereas tetracycline and ciprofloxacin were mostly removed. Antibiotic dissipation in soil, presumably dominated by adsorption mechanisms, was sufficient to neutralize 200 ppm of tetracycline; this concentration is considerably higher than reported contamination levels. Soil pellets from the tetracycline slurries were resuspended in a minimal volume of medium to maximize the interaction between bacteria and soil particles, but sensitive bacteria were still unaffected by tetracycline (
P
= 0.6). Thus, residual antibiotics in soil do not necessarily exert a selective pressure, and the degree to which the pharmaceutical remains bioactive depends on the antibiotic. Efforts to control antibiotic contamination would be better directed toward compounds that retain biological activity in soils (e.g., cephalosporins and florfenicol) because these are the antibiotics that could exert a selective pressure in the environment
Paralocks: Role-based information flow control and beyond
This paper presents Paralocks, a language for building expressive but statically verifiable fine-grained information flow policies. Paralocks combine the expressive power of Flow Locks (Broberg & Sands, ESOP\u2706) with the ability to express policies involving run-time principles, roles (in the style of role-based access control), and relations (such as "acts-for" in discretionary access control). We illustrate the Paralocks policy language by giving a simple encoding of Myers and Liskov\u27s Decentralized Label Model (DLM). Furthermore - and unlike the DLM - we provide an information flow semantics for full Paralock policies. Lastly we illustrate how Paralocks can be statically verified by providing a simple programming language incorporating Paralock policy specifications, and a static type system which soundly enforces information flow security according to the Paralock semantics
Transmission of Signals from the T Lymphocyte Antigen Receptor to the Genes Responsible for Cell Proliferation and Immune Function: The Missing Link
Urine from Treated Cattle Drives Selection for Cephalosporin Resistant Escherichia coli in Soil
The U.S. Food and Drug Administration recently issued new rules for using ceftiofur in food animals in part because of an increasing prevalence of enteric bacteria that are resistant to 3
rd
-generation cephalosporins. Parenteral ceftiofur treatment, however, has limited effects on enteric bacteria so we tested the hypothesis that excreted ceftiofur metabolites exert significant selection pressure for ceftiofur-resistant
Escherichia coli
in soil. Test matrices were prepared by mixing soil with bovine feces and adding urine containing ceftiofur metabolites (CFM) (0 ppm, ∼50 ppm and ∼100 ppm). Matrices were incubated at 23°C or 4°C for variable periods of time after which residual CFM was quantified using a bioassay.
Bla
CMY-2
plasmid-bearing ceftiofur resistant (cef
R
)
E. coli
and one-month old calves were used to study the selection effects of CFM and transmission of cef
R
bacteria from the environment back to animals. Our studies showed that urinary CFM (∼13 ppm final concentration) is biologically degraded in soil within 2.7 days at 23°C, but persists up to 23.3 days at 4°C. Even short-term persistence in soil provides a >1 log
10
advantage to resistant
E. coli
populations, resulting in significantly prolonged persistence of these bacteria in the soil (∼two months). We further show that resistant strains readily colonize calves by contact with contaminated bedding and without antibiotic selection pressure. Ceftiofur metabolites in urine amplify resistant
E. coli
populations and, if applicable to field conditions, this effect is far more compelling than reported selection
in vivo
after parenteral administration of ceftiofur. Because ceftiofur degradation is temperature dependent, these compounds may accumulate during colder months and this could further enhance selection as seasonal temperatures increase. If cost-effective engineered solutions can be developed to limit
ex vivo
selection, this may limit proliferation for ceftiofur resistant enteric bacteria while preserving the ability to use this important antibiotic in food animal production
- …