55 research outputs found

    Liquefaction resistance of fibre-reinforced silty sands under cyclic loading

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    Whether the so-called double porosity in soils with a loose and natural packing state is a concept with real-world implications is a fundamental yet controversial question in the study of cyclic undrained shear behaviour of fibre-reinforced silty sands. An attempt is made here to clarify the question by means of particle-level modelling combined with 41 undrained cyclic triaxial shear tests. The study shows that the initial Random Loose Packing changes to Random Close Packing and then Close Packing with silt content increments. The transition from random to close packing occurs at a threshold silt content which is relatively lower in coarser sands. For sands with 40% silt content. Irrespective of fine content, fibres tend to sit deep into the silt pellets and encrust the macro-pore spaces. Generally, increasing fibre content leads to an increase in the average number of contacts per particle, dilation and easier dissipation of excess pore water pressure, a decrease in contact forces and improved liquefaction resistance. For sands with >40% silt content, effectiveness of fibre reinforcement diminishes with increasing sand median size

    Safety and discontinuation rate of dimethyl fumarate (Zadiva®) in patients with multiple sclerosis: an observational retrospective study

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    BACKGROUND: This study evaluates the real-world safety and discontinuation rate of Zadiva® (generic product of dimethyl fumarate (DMF)) in Iranian patients with relapsing-remitting multiple sclerosis (RRMS), supplementing existing clinical evidence from randomized controlled trials. METHODS: This retrospective observational study evaluated the real-world safety and discontinuation rate of DMF in RRMS patients from Amir A'lam referral hospital's neurology clinic. Data on safety, discontinuation rate, and clinical disease activity were collected retrospectively. The study aimed to assess the discontinuation rate, safety, and reasons for discontinuation, as well as the number of patients experiencing a relapse, MRI activity, and EDSS scores. RESULTS: In total, 142 RRMS patients receiving DMF were included in the study, with 15 discontinuing treatment due to adverse events, lack of efficacy, or pregnancy. Notably, a significant reduction in relapse rates was observed, with 90.8% of patients remaining relapse-free throughout the study period. After 1 year of treatment with Zadiva®, only 17.6% of patients experienced MRI activity, whereas the EDSS score remained stable. CONCLUSIONS: This study provides important real-world data on the safety and tolerability of Zadiva® in RRMS patients. The results indicate that Zadiva® is generally well tolerated and safe, with a low discontinuation rate due to adverse events or lack of efficacy. These findings suggest that Zadiva® is an effective and safe treatment option for RRMS patients in real-world practice

    Significantly lower antigenicity of incobotulinumtoxin than abo- or onabotulinumtoxin

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    BACKGROUND: For many indications, BoNT/A is repetitively injected with the risk of developing neutralizing antibodies (NABs). Therefore, it is important to analyze whether there is a difference in antigenicity between the different licensed BoNT/A preparations. METHODS: In this cross-sectional study, the prevalence of NABs was tested by means of the sensitive mouse hemidiaphragm assay (MHDA) in 645 patients. Patients were split into those having exclusively been treated with the complex protein-free incoBoNT/A preparation (CF-MON group) and those having started BoNT/A therapy with a complex protein-containing BoNT/A preparation (CC-I group). This CC-I group was split into those patients who remained either on abo- or onaBoNT/A (CC-MON group) and those who had been treated with at least two BoNT/A preparations (CC-SWI group). To balance treatment duration, only CC-MON patients who did not start their BoNT/A therapy more than 10 years before recruitment (CC-MON-10 group) were further analyzed. The log-rank test was used to compare the prevalence of NABs in the CF-MON and CC-MON-10 group. RESULTS: In the CF-MON subgroup, no patient developed NABs. In the CC-I group, 84 patients were NAB-positive. NABs were found in 33.3% of those who switched preparations (CC-SWI) and in 5.9% of the CC-MON-10 group. Kaplan-Meier curves for remaining NAB-negative under continuous BoNT/A therapy were significantly different (p < 0.035) between the CF-MON and CC-MON-10 group. CONCLUSION: Frequent injections of a complex protein-containing BoNT/A preparation are associated with significantly higher risks of developing NABs than injections with the same frequency using the complex protein-free incoBoNT/A preparation

    A survey on health status of coldwater rearing and hatcheries fish farms in Iran (Mazandarn, Gilan, Ardebil, West Azerbaiejan, East Azerbaiejan and Kordestan provinces)

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    The national research plan with title of "Study on health status of Iran Coldwater hatchery and rearing farms" was done in order to identification and tracking of main causative agents of recent mortality in Iran Coldwater hatchery and rearing farms and recognize of infected zones and design of landscape distribution of Epizootic Coldwater fish diseases in the country. This plan was conducted parallel and in same time in some polar provinces of Coldwater fish production such as Mazandaran, Gilan, Ardebil, West Azerbaijan, East Azerbaijan and Kurdistan in three years from 2006-2008. In this regard, about 23,21 and 20 farms in Mazandaran province, 30 farms in West and East Azerbaijan and Kurdistan provinces and 19 farms in Gilan and Ardebil were selected as randomly and tracking were done yearly from 2006-2008. This research was conducted according to regular planning consists of farms visit that was done according to statistical plan and completion of Questionnaires and sampling. The findings in Mazandaran province revealed that fish infections background and infectious diseases were increased in period of 2006-2008. In fact, 56% of all fish farms in 2006, 71% in 2007 and 85% in 2008 were recorded as infected farms. In other side, average weight of fish final products was more 500gr in consume market. So, regarding to long period of fish culture in mentioned fish occurrence of more morbidity could be expected. The streptococcus infections were most important fish bacterial diseases that have more incidence and pathogenicity in collected questionnaires. Also it revealed more occurrences in summer season in above 15oC temperature in affected fish farms. Also, Enteric Redmouth Disease (ERM) and Saprolegniasis were reported as second and third degree in examined farms. Meanwhile, findings of control, prevention and treatment of our survey revealed that using of antibiotics and detergent materials were increased in mentioned province. Indeed, 34.7% of all fish farms in 2006, 71.4% in 2007 and 75% in 2008 have applied treatment operation and using of detergent materials in affected farms. In other side, frequent using of Erythromycin antibiotic was reported several times in 2008 so fish farmer faced to Bacterial resistance and should be using from Florfenicol as alternative antibacterial. Also, in feed sampling from all fish farms about 3 fish farms in 2006 and 5 fish farms in 2008 were faced with food poisoning that originated from high TVN and peroxidase in fish food consumed. These farms revealed mass mortality that stopped after change feeding regime. In conclusion absence of fish health management could be considered as main agent of mentioned mortality in Mazandaran province. The findings of our survey in West and East Azerbaijan and Kurdistan revealed that absence of sufficient experiences in fish farmers and their neglect from water quality concepts, farm cleanness, using of suitable detergent materials for fish ponds and instruments and disability in continuous monitoring of physic-chemical factors of consumed water could be considered as most important problems. So, fish morbidity and mortality, growth decrement and low production rate were expected. Unfortunately, despite the occurrence of infectious and non- infectious diseases in examined fish farms, there were no documents and information about diseases history, clinical signs in dead fish, feeding regime, fish mortality (rate of daily mortality, age and weight of moribund fish), treatment operation, drugs usage, growth rate, physico-chemical factors and fish density. So planning for control and prevention of mentioned diseases were unsuccessful in affected fish farms. Also, occurrence of some epizootic fish viral diseases such as VHS, IPN and IHN were observed frequently with mass mortality about 40100% in some examined fish farms that produced some tragic economic lost in the mentioned provinces. Similarly, some bacterial, fungal and parasitic diseases were observed repeatedly in some inspected farms such as Flavobacterium, streptococcus infections. Also, some unknown causative agents in parasitic diseases were observed several times such as Dactylogyrus, Gyrodactylus, Ichthyophthirius multifiliis, Trichodina, Chilodonella, Diplostomum and fungal diseases such as Saprolegniasis. In conclusion it seems that absence of fish health management, inadequate rate of hygienic technical services, absence of quarantine programs for transfer of new eyed-eggs, juvenile and live broodstocks packages without health certificates from authorized organizations, uncontrolled entry of foreign eyed-eggs (France, Denmark, Australia and Armenia) and neglect in using of suitable detergent materials for fish ponds, instruments, consumed water and infected eggs, not screening of broodstocks in hatcheries could be considered as most important causative agents in occurrence of infectious diseases and main problems in affected farms in mentioned provinces. Similarly, our findings in Gilan and Ardebil provinces revealed that their problems were similar to other provinces. In fact, neglect in establish of necessary Infrastructures in fish farms and dereliction in health management concepts could be considered as main reasons of occurrence of fish infectious and non-infectious diseases in studied fish farms in mentioned provinces. In fact, often fish farms visited hadn't suitable structures without control and prevention approach. There were not observed detergent using, quarantine programs and prevention methods. Entrance of unknown persons, birds and wild animals were ordinary in mentioned farms. Unfortunately level of farmer’s knowledge was low and no training courses and extension programs were planned by authorized organizations. Meanwhile, food storages were unsuitable and food packages were stored in inappropriate situation so poisoning conditions were increased in examined farms. In conclusion it could be finalized that Coldwater fish farms in Gilan and Ardebil provinces situated in insufficient position and correction of current situation are needed urgently. In final elicitation, it would be mentioned that lack of basic infrastructures could be introduced as most important reasonfor spread of diseases, mortality and related economic losses in studied provinces. Therefore, attention to environmental affairs and access to Sustainable Development are recommended. Also consideration of biosecurity regulations and health management concepts would be important requirements for modification and reformation of Coldwater fish farms in examined provinces towards A Better Tomorrow
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