499 research outputs found

    Study of potential activity of clove oil 10 % emulsifiable concentrate formulation on Two-spotted spider Mite Tetranychus urticae Koch (Acari: Tetranychidae)

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    Clove oil is reported to have a great range of biological activities against many species of pests; termites, cockroaches, aphids, weevils and moths, and many different usages such as perfume and food flavoring agent. This study aimed to determine the acaricidal activity of clove oil emulsifiable concentrate new formulation against two-spotted spider mites Tetranychus urticae. Clove oil was formulated as 10 % emulsifiable concentrate (EC). The new formula passed successfully all physical and chemical tests reported for emulsifiable concentrates. It was then tested biologically on the individuals of two-spotted spider mite T. urticae Koch (Acari: Tetranychidae) on two host plants beans and squash under laboratory conditions. In both cases, there were a direct relationship between the increase in the concentration of the formulation and the percentage of inhibition on the individuals of the two-spotted spider mite, after 72 hours of treatment, at concentrations of 20, 40, and 80 mg/ml the new formulation showed 10.30, 44.8, and 75 percent inhibition, respectively in case of beans, while squash at the same concentrations and for the same period of treatment showed 33.3, 40.7, and 51.9 percent inhibition, but the effect in case of beans was greater than that in case of squash as its EC50 value was lower than that in case of squash. In the case of the former, it was 39.81 mg/ml, whereas in the case of the latter, it was 79.43 mg/ml. Therefore, the new clove oil formulation can be used to combat the two-spotted spider mite

    Wave reflection at a free interface in an anisotropic pyroelectric medium with nonclassical thermoelasticity

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    In this paper, the well-established two-dimensional mathematical model for linear pyroelectric materials is employed to investigate the reflection of waves at the boundary between a vacuum and an elastic, transversely isotropic, pyroelectric material. A comparative study between the solutions of (a) classical thermoelasticity, (b) Cattaneo–Lord–Shulman theory and (c) Green–Lindsay theory equations, characterised by none, one and two relaxation times, respectively, is presented. Suitable boundary conditions are considered in order to determine the reflection coefficients when incident elasto–electro–thermal waves impinge the free interface. It is established that, in the quasi-electrostatic approximation, three different classes of waves: (1) two principally elastic waves, namely a quasi-longitudinal Primary (qP) wave and a quasi-transverse Secondary (qS) wave; and (2) a mainly thermal (qT) wave. The observed electrical effects are, on the other hand, a direct consequence of mechanical and thermal phenomena due to pyroelectric coupling. The computed reflection coefficients of plane qP waves are found to depend upon the angle of incidence, the elastic, electric and thermal parameters of the medium, as well as the thermal relaxation times. The special cases of normal and grazing incidence are also derived and discussed. Finally, the reflection coefficients are computed for cadmium selenide observing the influence of (1) the anisotropy of the material, (2) the electrical potential and (3) temperature variations and (4) the thermal relaxation times on the reflection coefficients

    The Antiviral Drug Valacyclovir Successfully Suppresses Salivary Gland Hypertrophy Virus (SGHV) in Laboratory Colonies of Glossina pallidipes

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    Many species of tsetse flies are infected with a virus that causes salivary gland hypertrophy (SGH) symptoms associated with a reduced fecundity and fertility. A high prevalence of SGH has been correlated with the collapse of two laboratory colonies of Glossina pallidipes and colony maintenance problems in a mass rearing facility in Ethiopia. Mass-production of G. pallidipes is crucial for programs of tsetse control including the sterile insect technique (SIT), and therefore requires a management strategy for this virus. Based on the homology of DNA polymerase between salivary gland hypertrophy virus and herpes viruses at the amino acid level, two antiviral drugs, valacyclovir and acyclovir, classically used against herpes viruses were selected and tested for their toxicity on tsetse flies and their impact on virus replication. While long term per os administration of acyclovir resulted in a significant reduction of productivity of the colonies, no negative effect was observed in colonies fed with valacyclovir-treated blood. Furthermore, treatment of a tsetse colony with valacyclovir for 83 weeks resulted in a significant reduction of viral loads and consequently suppression of SGH symptoms. The combination of initial selection of SGHV-negative flies by non-destructive PCR, a clean feeding system, and valacyclovir treatment resulted in a colony that was free of SGH syndromes in 33 weeks. This is the first report of the use of a drug to control a viral infection in an insect and of the demonstration that valacyclovir can be used to suppress SGH in colonies of G. pallidipes

    Knowledge and Awareness about Aggravating Factors of the Peptic Ulcer Disease: A Cross-Sectional Study

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    Background: Peptic ulcer disease is a gastrointestinal disorder due to the imbalance between the defense mechanism and gastric acid secretion. It affects 5-10% of the population worldwide and induces eight million deaths every year globally. In Sudan, this disease represents one of the major health problems. Limited studies have shown the knowledge level of Sudanese about aggravating factors of Peptic ulcer disease, which lead to more prevalent complications. Therefore, this study aimed to assess awareness about aggravating factors of peptic ulcer disease among the population of Khartoum state, Sudan. Method: A descriptive cross-sectional study targeted the general population in Khartoum state during the period from January to June 2022. We used an online survey form to collect data from the study population. The distribution of the questionnaire was done via social media tools. We analyzed the data using SPSS Software version 26. Results: The study included 398 participants, 40.7% of them male and 59.3% female, with mean age equal to 24.9 (SD=8.9), and a range between (18-64). Most of the participants (77.1%) were unmarried and (89.2%) were educated. The type of food was the most known risk factor (79.1%) and the weather changes were the least known risk factor (8.5%) that have effects on peptic ulcers. There also was a significant difference between educated and non-educated people based on the awareness of peptic ulcer risk factors, as the second was higher (p>0.000). Furthermore, people with peptic ulcers and people who have one or more members of their family with peptic ulcers scored more than nonpatients and those who did not have (p>0.000, p= 0.04; respectively). Conclusion: In conclusion, awareness about aggravating factors of peptic ulcers was variable among the population in Khartoum state. Our study findings revealed a high knowledge effect of type of food, helicobacter pylori, analgesic medications, drinking coffee, smoking, and social stress of the majority population. As for other factors, weather changes, genetic factors, and body weight were associated with a poor level of awareness. Lastly, these results need to be affirmed by furthermore research with a large sample among the general population in different regions in Sudan

    Diagnosis of exudative pleural effusion using ultrasound guided versus medical thoracoscopic pleural biopsy

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    AbstractIntroductionMedical thoracoscopy increases the diagnostic yield in patients with non-diagnosed pleural effusion when thoracocentesis and closed pleural biopsy (CPB) are non-diagnostic. Chest ultrasound (US) is a very useful imaging method for pleural diseases and the technique of ultra sound-guided cutting biopsy with a tru-cut needle has been well described.Aim of the workThe aim of this work was to diagnose exudative pleural effusion using ultrasound guided versus medical thoracoscopic pleural biopsy.Subjects and methodsForty patients with, non-diagnosed exudative pleural effusion admitted to the chest department, Alexandria university hospital, were enrolled after obtaining informed consents. All patients were subjected to; full history taking, thorough clinical examination, laboratory investigations including prothrombin activity and INR, biochemical, pathological and microbiological evaluation of the pleural aspirate and radiological evaluation. Then the patients were divided (randomly) into 2 groups each containing 20 patients. Pleural biopsies were performed using medical rigid thoracoscopy on group 1 and ultrasound guided tru-cut pleural biopsy on group 2.ResultsThe mean age in-group I was 55.0±13.05years and in-group II was 52.60±17.77years. There was no statistically significant difference between the two groups regarding age, sex, smoking, marital status and past medical conditions. There was no statistically significant difference between the two groups regarding radiological findings. There was no statistically significant difference between the two groups regarding the pleural fluid analysis. There was no statistically significant difference between the two groups regarding the gross pleural findings. In group II non- specific pleurisy was found in 5 (25.0%) patients (by thoracoscopy 1 of them was finally diagnosed as metastatic deposits from adenocarcinoma of unknown primary, one was confirmed to be tuberculous pleurisy and the remaining 3 cases were confirmed to be non- specific pleurisy). As regards complications in-group I, local wound infection occurred in 1 (5.0%) patient, and empyema occurred in 1 (5.0%) patient. In-group II, local wound infection occurred in 1 (5.0%) patient, and empyema occurred in 1 (5.0%) patient.ConclusionIt is better to use thoracoscopy in cases of undiagnosed exudative pleural effusion presented with a sufficient amount of pleural fluid to avoid lung injury while inserting the trocar. Whereas, ultrasound guided tru-cut pleural biopsy may be used in cases of undiagnosed exudative pleural effusion presented with thickened pleura but with an insufficient amount of pleural fluid

    Nodulation and nitrogen fixation of some wild legumes from differing habitats in Egypt

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    This study was devoted to exploring the natural nodulation and nitrogen fixation of wild legumes grown in different Egyptian habitats. These habitats are representative to four phytogeographical regions. Sites that inhabited by Melilotus indicus, Medicago polymorpha, Trifolium resupinatum, Trigonella hamosa and Vicia sativa in each region were selected for study. High nodulation, nitrogen fixation and plant biomass were recorded in plants grown at Nile region and Oases compared with those at Mediterranean region and Sinai. The inhibition in nodulation and potential of nitrogen fixation in legumes at MR and S were attributed to drought and low soil fertility. Differences in species, regions or their interaction have significant effect on nodulation, legheamoglobin, nitroginase activity and biomass of nodules, shoots and roots; the magnitude of effect due to different species was the greatest. Five rhizobial isolates (Sinorhizobium fredii, Rhizobium mesosinicum, Rhizobium daejeonense, Rhizobium huautlense, Rhizobium alamii) recovered from root nodules of the five species were identified by 16S rRNA gene sequence. The indigenous rhizobia of legumes grown at MR and S expected to be exhibit higher tolerance to the existing harsh environmental conditions. These rhizobia can be used as inoculants for crop legumes under unfavorable environmental conditions of agroecosystems or recently reclaimed desert. DOI: http://dx.doi.org/10.5281/zenodo.22401

    EFFECT OF FOLIAR SPRAYING WITH SEAWEEDS EXTRACT, CHITOSAN AND POTASSIUM SILICATE ON ROSMARINUS OFFICINALIS L. PLANTS IN SANDY SOIL

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    The present study was carried out at the Experimental Farm, Horticulture Department, Faculty of Agriculture, Suez Canal University during two seasons of 2017/2018 and 2018/2019 to study the effect of foliar application of seaweeds extract at 2, 4 and 6 ml/l, chitosan at 2, 4 and 6 ml/l and potassium silicate at 6, 9 and 12 ml/l as well as the interaction between seaweeds extract and chitosan on growth, biochemical, and essential oil characteristics of rosemary plants grown in a sandy soil. These compounds were applied as foliar spray three times after 15 days from planting. The results showed that foliar applications of seaweeds extract at 6 ml/l, chitosan at 6 ml/l and potassium silicate at 12 ml/l significantly affected all studied parameters compared with control. The results clearly indicated that the different applied treatments increased the measured growth characteristics i.e. plant height, number of branches/plant, fresh and dry weights as well parallel increase of photosynthetic pigments. Also, constituents of N, P, K, total carbohydrates, percentage of essential oil and the G.L.C. of essential oil of plant age were existed in the two assigned seasons. In addition, the most effective combined treatment was that of seaweed at 6 ml/l + chitosan at 6 ml/l in this respect

    Tsetse Salivary Gland Hypertrophy Virus: Hope or Hindrance for Tsetse Control?

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    Many species of tsetse flies (Diptera: Glossinidae) are infected with a virus that causes salivary gland hypertrophy (SGH), and flies with SGH symptoms have a reduced fecundity and fertility. The prevalence of SGH in wild tsetse populations is usually very low (0.2%–5%), but higher prevalence rates (15.2%) have been observed occasionally. The successful eradication of a Glossina austeni population from Unguja Island (Zanzibar) using an area-wide integrated pest management approach with a sterile insect technique (SIT) component (1994–1997) encouraged several African countries, including Ethiopia, to incorporate the SIT in their national tsetse control programs. A large facility to produce tsetse flies for SIT application in Ethiopia was inaugurated in 2007. To support this project, a Glossina pallidipes colony originating from Ethiopia was successfully established in 1996, but later up to 85% of adult flies displayed symptoms of SGH. As a result, the colony declined and became extinct by 2002. The difficulties experienced with the rearing of G. pallidipes, epitomized by the collapse of the G. pallidipes colony originating from Ethiopia, prompted the urgent need to develop management strategies for the salivary gland hypertrophy virus (SGHV) for this species. As a first step to identify suitable management strategies, the virus isolated from G. pallidipes (GpSGHV) was recently sequenced and research was initiated on virus transmission and pathology. Different approaches to prevent virus replication and its horizontal transmission during blood feeding have been proposed. These include the use of antiviral drugs such as acyclovir and valacyclovir added to the blood for feeding or the use of antibodies against SGHV virion proteins. In addition, preliminary attempts to silence the expression of an essential viral protein using RNA interference will be discussed

    Managing hytrosavirus infections in Glossina pallidipes colonies: Feeding regime affects the prevalence of the salivary gland hypertrophy syndrome

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    Many species of tsetse flies are infected by a virus that causes salivary gland hypertrophy (SGH) syndrome and the virus isolated from Glossina pallidipes (GpSGHV) has recently been sequenced. Flies with SGH have a reduced fecundity and fertility. Due to the deleterious impact of SGHV on G. pallidipes colonies, several approaches were investigated to develop a virus management strategy. Horizontal virus transmission is the major cause of the high prevalence of the GpSGHV in tsetse colonies. Implementation of a “clean feeding” regime (fresh blood offered to each set of flies so that there is only one feed per membrane), instead of the regular feeding regime (several successive feeds per membrane), was among the proposed approaches to reduce GpSGHV infections. However, due to the absence of disposable feeding equipment (feeding trays and silicone membranes), the implementation of a clean feeding approach remains economically difficult. We developed a new clean feeding approach applicable to large-scale tsetse production facilities using existing resources. The results indicate that implementing this approach is feasible and leads to a significant reduction in virus load from 109 virus copies in regular colonies to an average of 102.5 and eliminates the SGH syndrome from clean feeding colonies by28 months post implementation of this approach. The clean feeding approach also reduced the virus load from an average of 108 virus copy numbers to an average of 103 virus copies and SGH prevalence of 10% to 4% in flies fed after the clean fed colony. Taken together, these data indicate that the clean feeding approach is applicable in large-scale G. pallidipes production facilities and eliminates the deleterious effects of the virus and the SGH syndrome in these colonies

    Simple tools for assembling and searching high-density picolitre pyrophosphate sequence data

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    <p>Abstract</p> <p>Background</p> <p>The advent of pyrophosphate sequencing makes large volumes of sequencing data available at a lower cost than previously possible. However, the short read lengths are difficult to assemble and the large dataset is difficult to handle. During the sequencing of a virus from the tsetse fly, <it>Glossina pallidipes</it>, we found the need for tools to search quickly a set of reads for near exact text matches.</p> <p>Methods</p> <p>A set of tools is provided to search a large data set of pyrophosphate sequence reads under a "live" CD version of Linux on a standard PC that can be used by anyone without prior knowledge of Linux and without having to install a Linux setup on the computer. The tools permit short lengths of <it>de novo </it>assembly, checking of existing assembled sequences, selection and display of reads from the data set and gathering counts of sequences in the reads.</p> <p>Results</p> <p>Demonstrations are given of the use of the tools to help with checking an assembly against the fragment data set; investigating homopolymer lengths, repeat regions and polymorphisms; and resolving inserted bases caused by incomplete chain extension.</p> <p>Conclusion</p> <p>The additional information contained in a pyrophosphate sequencing data set beyond a basic assembly is difficult to access due to a lack of tools. The set of simple tools presented here would allow anyone with basic computer skills and a standard PC to access this information.</p
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