Control Alone (control + alone)

Distribution by Scientific Domains


Selected Abstracts


Beneficial links for the control of aphids: the effects of compost applications on predators and prey

JOURNAL OF APPLIED ECOLOGY, Issue 4 2008
James R. Bell
Summary 1Polyphagous predators, such as spiders and beetles, perform a fundamental ecosystem service as regulators of agricultural pests, particularly aphids. They are most effective when they colonize the crop before the pest has reached its exponential growth phase. However, this is also when predators find themselves in a state of near-starvation. 2Predator numbers can be enhanced by applications of different types of organic matter, but the mechanism is not clearly understood. One hypothesis is that compost applied to the field may introduce a new detrital food chain to maintain predators until the pest arrives, but this may also be detrimental to effective pest control, fostering a surplus of alternative prey and causing a switch away from the pest. To elucidate these possible outcomes, we report on the use of within-field compost applications on aphids and their predators, presenting 4 years of field-scale manipulations. 3We found both direct and indirect links between compost, aphids and predators. In years when compost-treated plots had significantly higher numbers of predators, aphids were in significantly lower numbers than in plots without compost. Conversely, when there was a lack of response by predators, aphid numbers showed similar trends in all treatments. 4In all years, alternative prey responded strongly to compost application and did not fluctuate at the level shown by predators, suggesting that these two prey groups were decoupled. Instead, the predicted positive feedback of compost on predators numbers was either weak or absent. 5Synthesis and applications. The effect of compost on aphids clearly requires further practical refinement if it is to provide constant pest suppression, making it difficult to provide specific management recommendations at this stage. In the short term, compost application may not always confer immediate benefits in terms of pest control alone but this must be set against other better known benefits (moisture retention, nutrients). In the long term, experiments measuring the full trophic pathway are needed to unravel the effects of organic matter type, application time and the siting of compost relative to the crop in order to optimise pest suppression potential. [source]


A lethal ovitrap-based mass trapping scheme for dengue control in Australia: II.

MEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2009
Impact on populations of the mosquito Aedes aegypti
Abstract. In Cairns, Australia, the impacts on Aedes aegypti L. (Diptera: Culicidae) populations of two types of ,lure & kill' (L&K) lethal ovitraps (LOs), the standard lethal ovitrap (SLO) and the biodegradable lethal ovitrap (BLO) were measured during three mass-trapping interventions. To assess the efficacy of the SLO, two interventions (one dry season and one wet season) were conducted in three discrete areas, each lasting 4 weeks, with the following treatments: (i) SLOs (>200 traps, ,4/premise), BG-sentinel traps (BGSs; ,15, 1/premise) and larval control (container reduction and methoprene treatment) and (ii) larval control alone, and (iii) untreated control. Female Ae. aegypti populations were monitored for 4 weeks pre- and post-treatment in all three areas using BGSs and sticky ovitraps (SOs) or non-lethal regular ovitraps (ROs). In the dry season, 206 SLOs and 15 BGSs set at 54 and 15 houses, respectively, caught and killed an estimated 419 and 73 female Ae. aegypti, respectively. No significant decrease in collection size of female Ae. aegypti could be attributed to the treatments. In the wet season, 243 SLOs and 15 BGSs killed ,993 and 119 female Ae. aegypti, respectively. The mean number of female Ae. aegypti collected after 4 weeks with SOs and BGSs was significantly less than the control (LSD post-hoc test). The third mass-trapping intervention was conducted using the BLO during the wet season in Cairns. For this trial, three treatment areas were each provided with BLOs (>500, ,4/premise) plus larval control, and an untreated control area was designated. Adult female Ae. aegypti were collected for 4 weeks pre- and post-treatment using 15 BGSs and 20 SOs. During this period, 53.2% of BLOs contained a total of 6654 Ae. aegypti eggs. Over the intervention period, collections of Ae. aegypti in the treatment areas were significantly less than in the control area for BGSs but not SOs. An influx of relatively large numbers of young females may have confounded the measurement of changes in populations of older females in these studies. This is an important issue, with implications for assessing delayed action control measures, such as LOs and parasites/pathogens that aim to change mosquito age structure. Finally, the high public acceptability of SLOs and BLOs, coupled with significant impacts on female Ae. aegypti populations in two of the three interventions reported here, suggest that mass trapping with SLOs and BLOs can be an effective component of a dengue control strategy. [source]


Latest news and product developments

PRESCRIBER, Issue 7 2008
Article first published online: 28 APR 200
Referrals from Boots The majority of people requesting Boots' erectile dysfunction or weight management programmes are referred to their GP(Pharm J 2008;280:297). The programmes are run under patient group directions and exclude people with elevated blood pressure, blood glucose or cholesterol. Over 80 per cent of customers screened for the erectile dysfunction programme in Manchester and two-thirds of those screened for the national obesity programme were referred. Vildagliptin: new DPP-4 inhibitor for diabetes Novartis has introduced the DPP-4 inhibitor vildagliptin for the treatment of type 2 diabetes. Two formulations are available: Galvus (vildagliptin 50mg) is licensed for use with metformin, a sulphonylurea or a thiazolidinedione when these agents do not achieve glycaemic control alone, and Eucreas (vildagliptin 50mg plus metformin 850 or 1000mg) is licensed for patients requiring combined therapy with vildagliptin and metformin. Inhibition of DPP-4 blocks the breakdown of the incretin hormones GIP and GLP-1, reducing fasting plasma glucose and postprandial hyperglycaemia. Vildagliptin is the second DPP-4 inhibitor to be introduced; the first was sitagliptin (Januvia), which has similar licensed indications. The third available drug acting on the incretin system is the incretinmimetic exenatide (Byetta); administered by injection, this is licensed for use with metformin and/or a sulphonylurea and is the only agent in this class to be approved for triple therapy. No comparative trials of these agents have been published. A month's treatment with twice-daily vildagliptin 50mg or either strength of vildagliptin plus metformin costs £31.76. Sitagliptin 100mg once daily costs £33.26. Sinusitis symptoms don't guide treatment The severity and duration of symptoms do not help to identify which patients with sinusitis will be helped by antibiotics, a new meta-analysis suggests (Lancet 2008;371: 908-14). The analysis of patient-level data from nine trials involving a total of 2547 adults showed that the number needed to treat (NNT) to cure one patient with rhinosinusitis was 15. Cure took longer to achieve in older patients and in those reporting symptoms for longer or with more severe symptoms. The authors comment that treatment is not justified given the risk of resistance and adverse effects and cost of antibiotics. Draft guidance from the National Institute for Health and Clinical Excellence (NICE) on the management of respiratory infections states that no antibiotic therapy or a delayed antibiotic prescribing strategy should be negotiated for patients with acute sinusitis. Taking cod liver oil leads to fewer NSAIDs Cod liver oil could help some patients with rheumatoid arthritis to reduce their NSAID consumption, according to a study from Dundee (Rheumatology online: 24 March 2008; doi: 10.1093/rheumatology/ ken024). A total of 97 patients were randomised to nine months' treatment with cod liver oil 10g per day or placebo. After 12 weeks, patients attempted to reduce or stop their use of NSAIDs. Significantly more of those taking cod liver oil achieved at least a 30 per cent reduction in NSAID use compared with placebo (39 vs 10 per cent). There were no differences in adverse effects or disease activity. Welsh prescriptions up The reduction in the prescription charge in Wales in 2004 was followed by an increase in prescribing of nonsedating antihistamines in wealthier areas, a study suggests (Health Policy online: 5 March 2008; doi:10.1016/j. healthpol.2008.01.006). In the two years preceding the cut, prescriptions for nonsedating antihistamines increased by about 7 per cent; in the two years after the cut, the increase was nearly 14 per cent. By contrast, there was no change in the rate of increase in the south-east of England (4,5 per cent in both periods). The increased growth in prescribing was statistically significant in the five least deprived but not in the five most deprived health boards in Wales. Aspirin linked with reduced asthma risk Low-dose aspirin is associated with a reduced risk of developing asthma, a new analysis of the Women's Health Study has shown (Thorax online: 13 March 2008; doi:10.1136/ thx.2007.091447). The analysis included 37 270 women with no asthma at baseline who were randomised to take placebo or aspirin 100mg every other day. After 10 years, 872 cases of asthma occurred in women taking aspirin and 963 with placebo, a 10 per cent reduction in risk. However, risk was not reduced in obese women. The mechanism by which aspirin may affect the risk of asthma is unknown. The latest evidence is consistent with findings published by the same investigators after analysis of two other large observational studies, the Physicians' Health Study and the Nurses Health Study. Anastrozole bone loss Long-term follow-up of the ATAC (Anastrozole, Tamoxifen, Alone or in Combination) trial has confirmed that adjuvant therapy with anastrozole (Arimidex) is associated with greater loss of bone mineral density (BMD) than tamoxifen in postmenopausal women with invasive primary breast cancer (J Clin Oncol 2008;26: 1051,7). After five years, median BMD was reduced by 6 and 7 per cent in the lumbar spine and hip with anastrozole compared with approximately 3 and 1 per cent respectively for tamoxifen, though no patients developed osteoporosis. Copyright © 2008 Wiley Interface Ltd [source]


Effect of oral contraceptives on tear physiology

OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 1 2001
Alan Tomlinson
Summary Variations in sex hormones due to the menstrual cycle (and oral contraceptives) were evaluated for their effect on tear physiology. Subjects were 18 females taking oral contraceptives or their age matched controls (no medication), aged 21,33 years. Symptoms of ocular discomfort (visual analog scale), tear film structure (TearScope), non-invasive tear thinning time (HirCal grid), evaporation rate (ServoMed evaporimeter), osmolality (Nanolitre Osmometer), tear turnover rate, tear volume (Fluorotron Master), and tear protein levels (HPLC) were measured around day 2 (D2), actually day 1,4 and day 19 (D19) actually day 18,21 of the cycle. No significant differences were found for any tear parameters between D2 and D19 for either pill users or controls alone, or in the comparison of pill users with controls. No effect on tear physiology was found for serum hormone changes induced by oral contraceptive use or by normal cyclic variations in healthy young females. [source]