Evaluation of the release and uptake of the fungicide tebuconazole from a novel microencapsulated formulation

Triazole fungicides, such as tebuconazole, have been pivotal in the control of both foliar and seed/soil-borne diseases of many crops, including cereals, since their introduction in the 1970s. Although routinely applied as a foliar spray, tebuconazole is also used as a seed treatment. The systemic nature of the fungicide may confer protection of plants from disease during the early stages of development. However, application rates are limited to between 1 and 7 g active ingredient (AI) per 100 kg of seed due to seed application causing reduced germination and stunting during early plant development. A novel technique whereby fungicides, including tebuconazole, are encapsulated using yeast cells as pre-formed microcapsules may provide a solution to the problem of phytotoxicity and allow seed treatments to be applied at higher rates, resulting in a reduction in total fungicide application required during the growing season. Several batches of microencapsulated tebuconazole were produced using yeast from different sources. These where tested for their potential for uptake, retention and subsequent delivery of the fungicide. The release of tebuconazole from the different yeast batches into water was assessed over a time course using liquid-liquid extraction (LLE) and GCMS. Results showed no differences in the release characteristics of tebuconazole observed between batches. Further to this the age of the batches tested was found to have no effect on release of tebuconazole into water, suggesting shelf-life would not be a problem with this technology. Repeated washing of a sample of microencapsulated tebuconazole with water suggested that the novel formulation could provide the gradual delivery of tebuconazole. An investigation of the phytotoxic effect of tebuconazole, applied as seed treatments at higher than recommended rates (40 g AI per 100 kg seed), showed the microencapsulated formulation had a significantly reduced impact on germination and early plant development, when compared to two commercial formulations of the fungicide, Mystique and Raxil. Further analysis, of the amount of tebuconazole accumulated by plants grown from treated seed, using solid phase extraction (SPE and GC-MS), showed there to be initially less fungicide in plants treated with the microencapsulated formulation. As plant development continued, the amount of tebuconazole recovered from plants treated with both the microencapsulated and conventional formulations became similar. Variation in the results, between replicate samples and also between growth stages led to a series of experiments investigating the possible effect of the growth environment and seed sowing density on tebuconazole uptake. However, no significant effects of these factors were observed. A comparison of the uptake of seed-applied microencapsulated and conventional formulations of tebuconazole between 2 and 19 weeks after sowing, showed there to be no significant differences between formulations used in the concentration of the fungicide accumulated in plants. However, a pronounced increase in plant accumulation of the fungicide was consistently observed between 17 and 19 weeks. It was suggested that this might be associated with roots becoming densely packed within the compost, encouraging fungicide uptake from the compost in the localised dressing zone around the seed. It was shown that tebuconazole became readily bound to the loam-based compost used during the research. Experiments conducted in 1m columns, containing tebuconazole applied to specific compost layers within the columns, confirmed the ability of wheat roots to recover the fungicide from the compost when they made contact with the specific layers

Letters of Arthur Henry Hallam

(print) xix, 841 p. : ill., port., facsims. ; 24 cmAcknowledgments ix -- List of Abbreviations xvii -- Editorial Principles xvii -- Introduction 1 -- The Letters 41 -- Appendix 795 -- Index 80

Situationally influenced tinnitus coping strategies: a mixed methods approach

Purpose: The primary aim of this study was to identify coping strategies used to manage problematic tinnitus situations. A secondary aim was to determine whether different approaches were related to the level of tinnitus distress, anxiety, depression, and insomnia experienced. Materials and methods: A cross-sectional survey design was implemented. The study sample was adults interested in undertaking an Internet-based intervention for tinnitus. Self-reported measures assessed the level of tinnitus distress, depression, anxiety, and insomnia. An open-ended question was used to obtain information about how problematic tinnitus situations were dealt with. Responses were investigated using qualitative content analysis to identify problematic situations. Further data analysis comprised of both qualitative and quantitative methods. Results: There were 240 participants (137 males, 103 females), with an average age of 48.16 years (SD: 22.70). Qualitative content analysis identified eight problematic tinnitus situations. Participants had either habituated to their tinnitus (7.9%), used active (63.3%), or passive (28.8%) coping styles to manage these situations. Those who had habituated to tinnitus or used active coping strategies had lower levels of tinnitus distress, anxiety, and depression. Conclusions: The main problematic tinnitus situations for this cohort were identified. Both active and passive coping styles were applied to approach these situations. The coping strategies used most frequently and utilised in the widest range of problematic situations were using sound enrichment and diverting attention

Mg II h + k emission lines as stellar activity indicators of main sequence F-K stars

The main purpose of this study is to use the IUE spectra in the analysis of magnetic activity of main sequence F-K stars. Combining IUE observations of MgII and optical spectroscopy of Ca II, the registry of ctivity of stars can be extended in time. We retrieved all the high-resolution spectra of F, G, and K main sequence stars observed by IUE (i.e. 1623 spectra of 259 F to K dwarf stars). We obtained the continuum surface flux near the Mg II h+k lines near 2800 \AA and the MgII line-core surface flux from the IUE spectra. We obtained a relation between the mean continuum flux near the MgII lines with the colour $B-V$ of the star. For a set of 117 nearly simultaneous observations of Mg II and Ca II fluxes of 21 F5 to K3 main sequence stars, we obtained a colour dependent relation between the Mount Wilson CaII S-index and the MgII emission line-core flux. As an application of this calibration, we computed the Mount Wilson index for all the dF to dK stars which have high resolution IUE spectra. For some of the most frequently observed main sequence stars, we analysed the Mount Wilson index S from the IUE spectra, together with the ones derived from visible spectra. We confirm the cyclic chromospheric activity of epsilon Eri (HD 22049) and beta Hydri (HD 2151), and we find a magnetic cycle in alpha Cen B (HD 128621). Complete abstract in the paper.Comment: 10 pages, accepted for publication in Astronomy and Astrophysic

Catastrophizing and fear of tinnitus predict quality of life in patients with chronic tinnitus

Objectives: It is well established that catastrophic misinterpretations and fear are involved in the suffering and disability of patients with chronic pain. This study investigated whether similar processes explain suffering and disability in patients with chronic tinnitus. We hypothesized that patients who catastrophically (mis)interpret their tinnitus would be more fearful of tinnitus, more vigilant toward their tinnitus, and report less quality of life. Moreover, tinnitus-related fear was expected to act as a mediator in reduced quality of life. Design: Sixty-one tinnitus patients from an outpatient ENT department of the University Hospital of Antwerp (Belgium) completed a number of questionnaires about their tinnitus. Hierarchical regression analyses were performed to test hypothesized associations and to assess mediation by tinnitus-related fear. Results: Analyses revealed significant associations between catastrophizing and fear and between catastrophizing and increased attention toward the tinnitus. Furthermore, both tinnitus-related catastrophizing and fear were negatively associated with quality of life; moreover, tinnitus-related fear fully mediated the association between catastrophizing about the tinnitus and quality of life. Conclusions: The findings confirm earlier suggestions that tinnitus-related concerns and fears are associated with impaired quality of life, which is in line with a cognitive behavioral account of chronic tinnitus. Future research avenues and clinical applications are discussed

Reliability and Validity of the Chinese (Mandarin) Tinnitus Handicap Inventory

ObjectivesThe Tinnitus Handicap Inventory (THI) is a commonly used self-reporting tinnitus questionnaire. We undertook this study to determine the reliability and validity of the Chinese-Mandarin version of the Tinnitus Handicap Inventory (THI-CM) for measuring tinnitus-related handicaps.MethodsWe tested the test-retest reliability, internal reliability, and construct validity of the THI-CM. Two-hundred patients seeking treatment for primary or secondary tinnitus in Southwest China were asked to complete THI-CM prior to clinical evaluation. Patients were evaluated by a clinician using standard methods, and 40 patients were asked to complete THI-CM a second time 14±3 days after the initial interview.ResultsThe test-retest reliability of THI-CM was high (Pearson correlation, 0.98), as was the internal reliability (Cronbach's α, 0.93). Factor analysis indicated that THI-CM has a unifactorial structure.ConclusionThe THI-CM version is reliable. The total score in THI-CM can be used to measure tinnitus-related handicaps in Mandarin-speaking populations

Social and emotional aspects of learning: Complementing, compensating and countering parental practices

This article draws on a study which investigated the interpretation and use of Social and Emotional Aspects of Learning (SEAL) in primary schools in the UK (the authors gratefully acknowledge Studentship funding from the Economic and Social Research Council for this study). The paper focuses on school staff members' perceptions about the intentions and purposes of the scheme. The testimonies of head teachers, management staff, teachers, teaching assistants, welfare assistants and pastoral staff members illustrated how the interpretation and use of SEAL was influenced by their perceptions about the pupils' parents and, in particular, parental ability to develop ‘appropriate’ social, emotional and behavioural skills in their children. In schools where parenting was positively appraised, SEAL was used to complement parenting practices; whilst in schools where parents were negatively appraised, SEAL was used to counter their endeavours. The scheme was also used to compensate for certain inadequacies that were deemed to be taking place in the home. These differing perceptions of parents were linked to social class, with the scheme being used to complement the practices of middle-class parents and to counter those of minority-ethnic and working-class people. We contend that this interpretation and use of the scheme helped to re-affirm the practices of the dominant culture whilst serving to marginalise the values of the less powerful groups in society. Implications of the study's findings are discussed and recommendations for staff, schools and policy are made

A Cross-Sectional Questionnaire Study of Tinnitus Awareness and Impact in a Population of Adult Cochlear Implant Users.

OBJECTIVES: The primary aim was to identify the proportion of individuals within the adult cochlear implant population who are aware of tinnitus and those who report a negative impact from this perception, using a bespoke questionnaire designed to limit bias. A secondary aim was to use qualitative analysis of open-text responses to identify themes linked to tinnitus perception in this population. DESIGN: A cross-sectional questionnaire study of a large clinical population who received an implant from Cambridge University Hospitals, United Kingdom. RESULTS: Seventy-five percent of respondents reported tinnitus awareness. When impact scores for six areas of difficulty were ranked, 13% of individuals ranked tinnitus their primary concern and nearly a third ranked tinnitus in the top two positions. Tinnitus impact was not found to reduce with duration since implantation. The most common open-text responses were linked to a general improvement postimplantation and acute tinnitus alleviation specific to times when the device was in use. CONCLUSIONS: Tinnitus is a problem for a significant proportion of individuals with a cochlear implant. Clinicians, scientists, and cochlear implant manufacturers should be aware that management of tinnitus may be a greater priority for an implantee than difficulties linked to speech perception. Where a positive effect of implantation was reported, there was greater evidence for masking of tinnitus via the implant rather than reversal of maladaptive plasticity

Different teams, same conclusions?: a systematic review of existing clinical guidelines for the assessment and treatment of tinnitus in adults

Background: Though clinical guidelines for assessment and treatment of chronic subjective tinnitus do exist, a comprehensive review of those guidelines has not been performed. The objective of this review was to identify current clinical guidelines, and compare their recommendations for the assessment and treatment of subjective tinnitus in adults. Method: We systematically searched a range of sources for clinical guidelines (as defined by the Institute of Medicine, United States) for the assessment and/or treatment of subjective tinnitus in adults. No restrictions on language or year of publication were applied to guidelines. Results: Clinical guidelines from Denmark, Germany, Sweden, The Netherlands, and the United States were included in the review. There was a high level of consistency across the guidelines with regard to recommendations for audiometric assessment, physical examination, use of a validated questionnaire(s) to assess tinnitus related distress, and referral to a psychologist when required. Cognitive behavioral treatment for tinnitus related distress, use of hearing aids in instances of hearing loss and recommendations against the use of medicines were consistent across the included guidelines. Differences between the guidelines centered on the use of imaging in assessment procedures and sound therapy as a form of treatment for tinnitus distress respectively. Conclusion: Given the level of commonality across tinnitus guidelines from different countries the development of a European guideline for the assessment and treatment of subjective tinnitus in adults seems feasible. This guideline would have the potential to benefit the large number of clinicians in countries where clinical guidelines do not yet exist, and would support standardization of treatment for patients across Europe