618 research outputs found
Facile development of cost effective and greener for all solid-state supercapacitor on paper substrate
No full textThe introduction of paper-based platforms for developing novel energy storage devices such as supercapacitors (SCs) highlights new promising opportunities in the field of flexible electronics. Herein, the use of paper-based substrate has shown reduced manufacturing cost and simplified coating process by screen-printing technology, as well as an improvement of the multilayer structure adhesion. The SC manufactured with Graphite ink mixed with Carbon Black (CB)/Prussian blue (PB) at different weight ratios (0, 3, 4, 5, 7, and 10 wt %) shows good performances. An optimum weight ratio of carbon black/prussian blue. 4 wt % is consistent with the following features: i) specific capacitance of 253 mF/cm2 at 0.01 V/s, ii) specific energy density of 0.5 mWh/cm2, iii) specific power density of 0.1 mW/cm2, and iv) good cycling stability (94%) after 5000 cycles. The proposed fabrication approach exhibits a simple scale-up, a low environmental impact and a decrease of manufacturing costs: it provides self-supporting electrodes based on a mixture of graphite ink and CB/PB nanocomposite
Sulodexide for Diabetic-Induced Disabilities: A Systematic Review and Meta-Analysis
No full textIntroduction Micro- and macrovascular complications of diabetes are leading morbidities in the world population. They are responsible not only for increased mortality but also severe disabilities, which jeopardize quality of life (e.g., blindness, walking limitations, and renal failure requiring dialysis). The new antidiabetic agents (e.g., glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter inhibitors) are increasingly recognized as breakthrough agents in the treatment of diabetes and prevention of diabetic complications. However, drugs effective in preventing and treating diabetic disabilities are still needed and sulodexide could be one of those able to address the unmet clinical needs of the new antidiabetic agents. Methods We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and the World Health Organization (WHO) International Clinical Trials Registry Platform Search Portal. We also manually searched potentially relevant journals, conference proceedings, and journal supplements. Any study monitoring any effect of sulodexide in subjects with diabetes, in relation to renal, vascular, and ocular complication, was considered. Treatment effects were estimated using standardized mean differences (SMDs), mean differences (MDs), and risk ratios (RRs), as appropriate. We calculated 95% confidence interval (CIs) and heterogeneity (Q, tau, and I-2). Results The search found 45 studies with 2817 participants (mean age 57 years; 63% male). The 26 randomized controlled studies included 2074 participants (mean age 58.8 years; 66% male). Sulodexide reduced the impact of diabetic retinopathy; increased the pain-free and maximal walking distance in peripheral arterial disease; accelerated the healing of diabetes-associated trophic ulcers; and decreased the rate of albumin excretion in subjects with nephropathy. The risk of adverse events (AEs) was not different between sulodexide and controls. Conclusion Sulodexide has a beneficial effect on the ocular, peripheral arterial disease, trophic ulcers, and renal complications of diabetes without increasing the risk of AEs
Smartphone-integrated electrochemical (bio) sensors as smart and reliable analytical tools
No full textCurrent and emerging treatment options for myopic choroidal neovascularization
No full textLeila El Matri, Ahmed Chebil, Fedra Kort Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of El Manar, Tunis, Tunisia Abstract: Choroidal neovascularization (CNV) is the main cause of visual impairment in highly myopic patients younger than 50 years of age. There are different treatments for myopic CNV (mCNV), with 5- to 10-year outcomes currently. Chorioretinal atrophy is still the most important determinant factor for visual outcome. The purpose of this study is to provide an overview of the current treatments for mCNV, including laser, surgical management, verteporfin photodynamic therapy, and mainly anti-vascular endothelial growth factor therapy. Emerging treatment options are also discussed. Keywords: myopia, choroidal neovascularization, current treatment, emerging treatmen
Explaining drivers of farmers’ willingness for early adoption of enhanced irrigation technologies: case of Tunisia
No full textThe objective of this paper is to identify the influencing factors of farmers' willingness for early adoption of enhanced irrigation technologies in Tunisia. We estimate a multinomial logit model with data from 931 farmers in Central (Chebika) and Northern (Fernana) of Tunisia. Regression results reveal that early adoption is positively influenced by levels of extension service quality, trust in farmers' associations and extension agents, farmer's perception towards the innovation, credit access, and off-farm income. However, it is negatively affected by market access issues, risk aversion, and age. Risk, trust, and perception towards technology are important factors in driving early adoption decision. The findings imply that farmers training on water conservation technologies, financial support for innovation adoption, awareness of young farmers about the opportunities of agricultural innovation, incentives to farmers' associations in order to improve their market access, and inclusive participatory approaches during technology generation and transfer are all accelerators of early adoption of innovations by farmers
A 3D printed platform for sample treatment and detection of phytic acid in spinach leaves using a paper-based electrochemical biosensor
No full textPhytic acid is a phosphorylated derivative of myo-inositol that is ubiquitous in plants and serves as the primary storage form of phosphorus. In human nutrition, phytic acid is considered an anti-nutrient because it chelates essential minerals, including calcium, iron, and zinc. This binding action reduces the bioavailability of these metals, highlighting the importance of monitoring phytic acid in food. Herein, we reported a novel and fully printed analytical platform for the quantification of phytic acid in spinach leaves. The integrated device comprises an electrochemical biosensor fabricated on office paper, combined with a custom-designed 3D printed grinder to accomplish the phytic acid extraction from ground spinach leaves using HCl. The solution extracted from the leaves containing phytic acid is transferred onto a filter pad in contact with the biosensor using a 3D printed funnel. The detection of phytic acid was made by using paper-based printed electrode modified with phytase enzyme. The enzymatic by-product, phosphate, reacts with ammonium molybdate preloaded on the filter pad to form an electroactive phosphomolybdic complex, which is then quantified at the working electrode surface using cyclic voltammetry. A linear range comprised between 1.8 and 50 mu M was observed, with a limit of detection of 0.5 mu M. Additionally, the biosensing platform exhibits high selectivity in the presence of potential interferents, including myo-inositol, ascorbic acid, and divalent metal cations. The accuracy of the biosensor was evaluated in spinach leaf samples, with percentage recoveries between 91 % and 109 %
Virulence spectra and geographical distribution of Mal Secco disease of citrus caused by Phoma tracheiphila in the Mediterranean countries: Tunisia and Italy
No full textThis work aimed to find out patterns of virulence
variability of a Phoma tracheiphila population of
51 isolates, to determine geographic distribution of Mal
Secco disease in citrus orchards of six Mediterranean
countries and also to establish correlation between geographic
distribution and pathotypic distance of P. tr
population structure over our sampling spatial scale.
Based on unweighted pair-group method with arithmetic
averaging clustering and mean disease rating scores,
three distinct virulence groups were identified. The 51
isolates were classified into 20 pathotypes. Extensive
virulence variability was detected in 51 isolates of P. tr
causing MSD of citrus in the Mediterranean basin.
Regression plot between pairwise virulence and geographical
distance showed that virulence is independent
of the geographical origin and that isolates collected
from the same country have different degrees of virulence.
The lack of significant correlation between virulence
and geographic structure confirmed the absence of
isolation-by-distance pattern, suggesting non-regular and non-gradual dispersal of the pathogen over this
spatial scale
Irrigation water pricing between governmental policies and farmers’ perception: Implications for green-houses horticultural production in Teboulba (Tunisia)
No full textA positive mathematical programming model was constructed in this study to assess the effect of three water pricing scenarios on Teboulba’s agricultural production systems. The effects of these scenarios were estimated for three groups of farmers from three irrigated districts. Results show that water demand in group 1 remains inelastic until achieving the price of 0.20 TD. A price above this level decreases water consumption, farmer’s incomes as well as seasonal labor demand. For groups 2 and 3, the water demand curves remain highly inelastic even with a full cost recovery price. However, once reaching this last price, the model shows important income reductions reaching 20% of the current observed income. Moreover, a pricing policy aiming to recover operational and maintenance costs and which will be implemented independently from other economic, social and environmental measures can threaten the sustainability of the production systems in the region.Water pricing, positive mathematical programming, greenhouses, economic impact, Teboulba, Environmental Economics and Policy, Farm Management, Resource /Energy Economics and Policy, Q15, Q18,
Factors affecting farmers’ willingness to adopt salt-tolerant forage crops in south-eastern Tunisia
No full textThis paper analyzed the factors that affect farmers’ willingness to adopt salt-tolerant forage for livestock, using a Tobit model. The data used for the empirical analysis was obtained from a survey of 97 farmers in southeastern Tunisia. The results of this study show that variables related to age, education level, the salinity level of water and membership in a farmers’ association do not significantly influence the degree to which salt-tolerant forage production is adopted. It did, however, find a positive relationship between off-farm income availability and adoption. In addition, the flock size variable, expressed in Standard Livestock Units, has a significant and positive relationship with adoption. This indicates farmers’ need to cover their forage deficit. Agricultural extension services should ensure that the requisite forage species are made available, and work with farmers to encourage them to adopt salt-tolerant forage species and pass on their knowledge to other farmers.Farmers’ willingness to adopt, Salt-tolerant forage, Tobit model, Tunisia, Crop Production/Industries,
Irrigation water use efficiency in collective irrigated schemes of Tunisia: determinants and potential irrigation cost reduction
No full textThis study aims first to measure the farm specific irrigation water use efficiency (IWUE), through non parametric DEA model; and second to evaluate the potential irrigation cost reductions and identify the main factors causing variations in IWUE among the sample farms. Cross sectional data collected from a sample of 75 farms participating in the WaDImena project in Nadhour region (northern Tunisia) was used for this aim. The results showed that the average level of IWUE across the farm sample was around 61.2% under variable returns to scale (VRS) assumption. However, the estimated mean irrigation water technical cost efficiency (ITCE) is much higher than IWUE. Farmers would be able to reduce their actual cost by 5% under VRS by adjusting irrigation water to its efficient level. This low level of cost reductions is consistent with the existing literature about IWUE in Tunisia. Moreover, education level of farmers, access to credit and agricultural extension service showed a positive relationship with the IWUE in our case study.Resource /Energy Economics and Policy,
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