1,061 research outputs found
Microbial Biocontrol of Post-harvest Fungal Rot in Apples: Current State of the Science
Our study consists of a careful literature review carried out with the aim of better understanding the models developed in the field of biocontrol of postharvest fungal rot in apples (PHFRA) over the past two decades. It aims, more specifically, to shed light on the progress made by examining the products developed, their nature, their target pathogens, their effectiveness, theirs modes of action and the stage of their development. The post-harvest biocontrol of apples has made remarkable progress during the last twenty years of research. Several products (yeasts, bacteria, filamentous fungi and actinomycetes) have been selected. Some, are already marketed, others are at different stages of development. However, several points limit the optimal use of microbial antagonists in the bio-management of post-harvest apple rots as an alternative to chemicals. It is, in fact, still necessary to develop appropriate formulations of these microbial biocontrol agents, to better study their mechanisms of action, to test them under commercial conditions and against a broad spectrum of pathogens and hosts. However, although sometimes considered less effective than chemical treatments, biocontrol products based on microorganisms have major advantages for an application in an integrated post-harvest apple protection strategy
Use of Plant Extracts in the Control of Post-Harvest Fungal Rots in Apples
Different fungi alter apples in the post-harvest period, causing considerable economic losses and risks to consumer health due to the mycotoxins that some of these fungi produce. The control of these fungal alterations in apples is mainly dependent on the use of chemical fungicides, the effectiveness of which has been well proven. However, this use is subject to restrictions due to growing concerns about risks to human health and the environment and the continued development of pathogen resistance to commonly used fungicides. A new approach to control post-harvest fungi has been implemented through the application of plant extract.It is estimated that there are more than 250,000 higher plant species on Earth that can be evaluated for their antimicrobial bioactive chemical compounds. In recent decades, researchers have evaluated plant extracts and essential oils against fungi responsible for post-harvest apple rot. Interesting results have been obtained. The purpose of this project is to summarize and discuss the results of in vitro and in situ experiments of different literatures concerning the effects of compounds derived from plants on the control of fungi responsible for rotting apples in storage
Isolation and X-ray crystal structure of tetrahydroisoquinoline alkaloids from Calycotome villosa Subsp. intermedias
Two tetrahydroisoquinoline alkaloids were extracted from the alkaloid fraction of a methanol extract of the seeds of Calycotome Villosa Subsp. intermedia. Their structures were established as (R)-1-hydroxymethyl-7-8-dimethoxy-1,2,3,4-tetrahydro- isoquinoline (1) and (S)-7-hydroxymethyl-2-3-dimethoxy-7,8,9,10-tetrahydroisoquinoline chloride (2) by spectroscopic techniques and X-ray diffraction analysis
Détermination du point de performance des portiques en B.A par la méthode statique non linéaire pushover
The purpose of this work is determination of the performance point of a frame for different soil type, the location of this point on the curve capacity will predict the behavior of the frame in case of earthquakes, this method consists in a first step to apply static loads on the frame, the non linear behavior of the structure is defined, the nonlinearity of the structure is introduced with the use of plastic hinges, the second step is to find the capacity curve by transforming respectively shear at the base and displacement in the top to acceleration and displacement corresponding to a system of a single degree of freedom , finally results of performance point will be discussed. Le but du présent travail consiste à déterminer le point de performance des portiques en mettant l’accent sur l’influence du site sur les dégâts observés, l’emplacement de ce point sur la courbe capacité permettra de prédire le comportement réel du bâtiment en cas de séismes. Cette méthode consiste dans une première étape à appliquer des charges statiques équivalentes d’allure triangulaire sur le portique étudié, le comportement non linéaire de la structure sera défini, la non linéarité de la structure est introduite au moyen de rotules plastiques de flexion et de cisaillement., La seconde étape consiste à trouver la courbe de capacité en transformant respectivement l’effort tranchant à la base et le déplacement du sommet de l’analyse push over à l’accélération et le déplacement correspondant à un système à un seul degré de liberté, finalement les résultats seront discutés
Prostatic fossa calculus
A 70-year-old man presented for evaluation of recurrent urinary tract infection. He had history of hypertension and had undergone suprapubic prostatectomy 8 years ago for enlarged obstructive prostate. Digital rectal examination found a stony irregular prostate and urine culture grew Escherichia Coli that was susceptible to Cephalosporines. As part of the evaluation, a plain radiograph was performed and incidentally showed a radiopaque prostatic calculus (Red arrows). A retrograde urethrocystography, performed after a 10-days course of antibiotics, confirmed the presence of an approximately 35 mm non-obstructive calculus occupying almost the whole prostatic bed (Red arrows) with a stricture of the membranous urethra (Yellow arrow), the bladder however showed no abnormalities (Orange arrows). Stones that form in the prostatic fossa are uncommon but can occur after all forms of prostatectomy. They are caused by a ligature, infection, a chip of prostate left behind in the prostatic bed or as a result of an iatrogenic urethral stricture. A meticulous operative and postoperative care is the best prevention of such a complication. Our patient was treated endoscopically by the combination of urethrotomy and transurethral ultrasonic lithotripsy. At 6 months follow-up, he voided properly and had a sterile urine culture.Pan African Medical Journal 2015; 2
The financial impacts of board mechanisms on performance: The case of listed Moroccan banks
Purpose: The present study examines the impact of corporate governance mechanisms on listed Moroccan banks' financial performance.
Research methodology: This study investigates the relationship between listed banks' governance mechanisms and financial performance in the CSE for six years between 2014-2019. This study employs three performance measures, return on assets, return on equity, and Tobin's Q, to determine bank performance. This research uses the GMM EGLS approach to analyze data. In the first phase of this empirical research, we did use OLS, Fixed Effects, and Radom Effects regressions to show their inefficiency.
Results: Our results portray that most board mechanisms have a negative impact on financial performance. In comparison, the audit committee and nomination & remuneration committee have a positive effect on financial performance.
Limitations: Many qualitative and quantitative factors could influence financial performance and not only the used variables in this paper.
Contribution: This research shows that the dynamic connection between corporate governance and financial performance is robust in the Moroccan banking context. Also, our study has important implications for establishing good corporate governance practices in emerging economies
The effects of corporate governance mechanisms on earnings management: Empirical evidence from Moroccan listed firms
Purpose: The purpose of the study is to systematically review and examine the effectiveness of corporate governance mechanisms in restraining earnings management among the listed firms of the Casablanca Stock Exchange.
Research methodology: In this study, we used the modified Jones model to calculate discretionary accruals. Our sample comprises 27 firms covering the period from 2016 to 2018, analyzed by the EGLS estimator.
Results: Our empirical results show that gender diversity, board size, and audit committee independence reduce the managers' discretion. Simultaneously, we found a significantly positive association between earning management and different corporate governance characteristics such as CEO duality, institutional investor ownership, and family ownership. We do not find any evidence that audit committee size, ownership concentration, and managerial ownership significantly influence discretionary accruals.
Limitations: This study's main limitation is that we did not address the direction of discretionary accruals, which does not allow us to detect the motivational aspects behind earnings management.
Contribution: The results of this study will help Moroccan authorities in their formulation of an appropriate regulatory framework because very few studies have been conducted in this area in the case of the Moroccan listed companies, especially with a large set of governance variables as our empirical model
A Novel Approach to Reduce the Unicast Bandwidth of an IPTV System in a High-Speed Access Network
Channel change time is a critical quality of experience (QOE) metric for IP-based video delivery systems such as Internet Protocol Television (IPTV). An interesting channel change acceleration scheme based on peer-assisted delivery was recently proposed, which consists of deploying one FCC server (Fast Channel Change Server) in the IP backbone in order to send the unicast stream to the STB (Set-Top Box) before sending the normal multicast stream after each channel change. However, deploying such a solution will cause high bandwidth usage in the network because of the huge unicast traffic sent by the FCC server to the STBs. In this paper, we propose a new solution to reduce the bandwidth occupancy of the unicast traffic, by deploying the FCC server capabilities on the user STB. This means that, after each channel change request, the STB will receive the unicast traffic from another STB instead of the central server. By using this method, the unicast traffic will not pass through the IP network; it will be a peer-to-peer communication via the Access Network only. Extensive simulation results are presented to demonstrate the robustness of our new solution
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