21 research outputs found

    Evaluation of the users value of salts against apple scab and powdery mildew for fruit production

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    The research was aimed at finding anti resistance strategies for Integrated fruit growing. As the salts tested may be approvable for organic farming, the trial results are also of value for the development of scab an mildew control strategies for organic fruit growing. As new fungicides are mainly unisite action fungicides, the problem of fungicide resistance development is becoming more important every year. Combining chemical fungicides, which is the best anti-resistance strategy, is not always possible or recommended in the case when the number of available chemical fungicides are limited or a reduction in fungicide use is asked for. Therefore the use of salts as an anti-resistance strategy was looked upon. The salts evaluated were K(HCO3), KH2PO3, KHPO4 and K2SiO3. When using these salts as an anti-resistance strategy the efficacy obtained when spraying the compounds alone was often to low to be used in rotation with chemical fungicides. Only with K(HCO3)2 a good efficacy can be observed in some years. The variation in efficacy with K(HCO3)2 observed is higher for powdery mildew. K(HCO3)2 can be considered as a ideal product for scab control in organic orchards at moments of low infection risk

    Improving control of storage diseases on apple by combining biological and physical post-harvest methods

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    Post-harvest non-chemical treatments consists of a large range of different approaches, including strengthening of the commodity’s natural defence mechanisms, thermotherapy, application of antagonistic microorganisms and natural antimicrobial substances. NEX0101 is a promising antagonistic biocontrol agent containing the yeast Candida oleophila as the active ingredient. NEX0101 was developed by Bionext, a spin-off from the laboratory of Dr. H. Jijakli, and is currently evaluated for commercial use. The product contains a yeast strain isolated from apple fruit and was originally developed for the control of post-harvest diseases on apple. The antifungal effectiveness of this antagonist can be increased by addition of calcium salts. As the mode of action of this yeast is based on the colonisation of wounds, the mean targets of NEX0101 are blue mould, caused by Penicillium expansum, and grey mould, caused by Botrytis cinerea. Facing possible latent infections, thermotherapy by using hot water treatments could provide an advanced control towards lenticelrot (Gloeosporium spp.). A combination of both physical and biological treatment techniques could broaden the spectrum to all key pathogens on apple and pear. The use of NEX0101 for the control of P. expansum was examined in combination with calcium gluconate. According to the results the combination NEX0101 with calcium gluconate provides an advanced mould control towards P. expansum The best results were achieved using NEX0101 in combination with post-harvest dipping by thermotherapy. The hot water treatment alone was clearly inefficient towards wound parasite P. expansum, on the contrary thermotherapy stimulates the decay caused by this postharvest pathogen. For the future a combination of biological and physical treatments could offer a worthy non-chemical alternative for organic and integrated fruit growers towards fruit rot decay, although more research is necessary to implement these methods in practice

    Development and Validation of a Risk Score for Chronic Kidney Disease in HIV Infection Using Prospective Cohort Data from the D:A:D Study

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    Ristola M. on työryhmien DAD Study Grp ; Royal Free Hosp Clin Cohort ; INSIGHT Study Grp ; SMART Study Grp ; ESPRIT Study Grp jäsen.Background Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice. Methods and Findings A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with >= 3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1: 393 chance of developing CKD in the next 5 y in the low risk group (risk score = 5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1,702 (95% CI 1,166-3,367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2,548 individuals, of whom 94 individuals developed CKD (3.7%) during 18,376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2,013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8,452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria. Conclusions Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.Peer reviewe

    Investigating the performance of thermonebulisation fungicide fogging system for loaded fruit storage room using CFD model

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    The original publication is available at http://www.sciencedirect.com/To study the operation of postharvest storage fungicide fogging systems, a CFD model was used. The modelling was based on an Eulerian–Lagrangian multiphase flow model. The effect of air circulation rate, circulation interval, bin design, stacking pattern and room design on deposition of fungicide was investigated. Air circulation rates of 0 m3 h 1 (no circulation), 2100 and 6800 m3 h 1 were used. Interval circulation of air was also investigated. The highest fungicide deposition was observed during fogging without circulation while the lowest deposition corresponded to fogging with the highest circulation rate. For the considered on/off combination times, the effect of circulation interval on overall average deposition and uniformity was not significantly different from the case of fogging with continuous air circulation. Bin with higher vent hole ratio and the presence of air deflector increased the amount and uniformity of deposition. Good agreement was found between measured and predicted results of deposition of fungicide particles.Publishers' Versio

    CFD model development and validation of a thermonebulisation fungicide fogging system for postharvest storage of fruit

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    The original publication is available at http://www.sciencedirect.com/Postharvest treatments of fruits in storage rooms using a fogging system is a recent development that offer a promising means to reduce the use of fungicides in the orchards, where ecological and environmental risks are higher than in the closed environment of the storage room. To investigate the effectiveness of postharvest storage fungicide fogging systems, a computational fluid dynamics (CFD) model was developed and validated. A discrete element (DE) method was applied to generate a random stacking of spherical fruits in a typical bin. The CFD model was then employed to study explicitly the air and fungicide particle flow through the bin vent holes and through the voids of the stack, and to predict the deposition behaviour of the fungicide particle on the products. For model validation purposes, a standardized set-up was used with a single fruit bin positioned in a cold store that was operated at different air flow rates. Good agreement was found between measured and predicted results of deposition profiles of fungicide particles. The deposition on the top layer of the fruit stack was higher than the bottom one, and higher deposition was observed on the top sides than on the bottom sides of the fruit. The effect of air flow rates and different bin handling parameters on fungicide particles flow and deposition were investigated. Air circulation rates of 0 m3 h 1 (no air circulation), 4080 m3 h 1 and 6800 m3 h 1 and 9520 m3 h 1 were used. The highest fungicide deposition on the fruit was observed during fogging without air circulation while the lowest deposition corresponded to fogging with the highest air circulation rate. Covering the top of the bin with foil and removing the bottom plastic foam that is usually placed on the bottom floor of the bin improves the uniformity of fungicide deposition throughout the bin. Removing the bottom plastic liner increased the average deposition of the fungicide particles, while covering the top of the bin decreased the average depositionPublishers' Versio

    Investigating the performance of thermonebulisation fungicide fogging system for loaded fruit storage room using CFD model

    No full text
    The original publication is available at http://www.sciencedirect.com/To study the operation of postharvest storage fungicide fogging systems, a CFD model was used. The modelling was based on an Eulerian–Lagrangian multiphase flow model. The effect of air circulation rate, circulation interval, bin design, stacking pattern and room design on deposition of fungicide was investigated. Air circulation rates of 0 m3 h 1 (no circulation), 2100 and 6800 m3 h 1 were used. Interval circulation of air was also investigated. The highest fungicide deposition was observed during fogging without circulation while the lowest deposition corresponded to fogging with the highest circulation rate. For the considered on/off combination times, the effect of circulation interval on overall average deposition and uniformity was not significantly different from the case of fogging with continuous air circulation. Bin with higher vent hole ratio and the presence of air deflector increased the amount and uniformity of deposition. Good agreement was found between measured and predicted results of deposition of fungicide particles.Publishers' Versio
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