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Due to the several side effects of synthetic pesticides, including environmental pollution, threats to human health, and the development of pest resistance to insecticides, the use of alternative healthy, available and efficient agents in pest management strategies is necessary. Recently, the use of essential oil obtained from aromatic plants has shown significant potential for insect pest management. For this reason, the essential oil isolated from seeds of Thapsia garganica L. was investigated for the first time for its chemical profile, and its toxicity and repellency effects against Tribolium castaneum adults. Qualitative and quantitative analyses of the chemical composition by gas chromatography coupled to mass spectrometry (GC/MS) revealed the presence of 18 organic volatiles representing 96.8 % of the total constituents. The main compounds were 1,4-dimethylazulene (51.3 %) followed by methyl palmitate (8.2 %), methyl linoleate (6.2 %) and costol (5.1 %). Concerning the repellent effect, results revealed that SEO (Seed Essential Oil) was very repellent towards T. castaneum adults, with 100 % repellency after 2 h of exposure. Furthermore, the essential oil exhibited remarkable contact toxicity against T. castaneum (93.3 % of mortality) at the concentration of 10 % (v/v). The median lethal dose (LD50) of the topical application of the seed essential oil was 4.4 %. These encouraging outcomes suggested that the essential oil from T. garganica seeds could be considered a potent natural alternative to residual persistent and toxic insecticides.  相似文献   
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Many subtypes of acute lymphoblastic leukemia (ALL) are associated with specific chromosomal rearrangements. The complex translocation t(9;14;14), a variant of the translocation (14;14)(q11;q32), is a rare but recurrent chromosomal abnormality involving the immunoglobulin heavy-chain (IGH) and CCAAT enhancer-binding protein (CEBPE) genes in B-lineage ALL (B-ALL) and may represent a new B-ALL subgroup. We report here the case of a 5-year-old girl with B-ALL, positive for CD19, CD38 and HLA-DR. A direct technique and G-banding were used for chromosomal analysis and fluorescentin situ hybridization (FISH) with BAC probes was used to investigate a possible rearrangement of the IGH andCEBPE genes. The karyotype exhibit the chromosomal aberration 46,XX,del(9)(p21),t(14;14)(q11;q32). FISH with dual-color break-apartIGH-specific and CEPBE-specific bacterial artificial chromosome (BAC) probes showed a complex t(9;14;14) associated with a deletion of cyclin-dependent kinase inhibitor 2A (CDKN2A) and paired box gene 5 (PAX5) at 9p21-13 and duplication of the fusion gene IGH-CEBPE.  相似文献   
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BackgroundLymphatic filariasis (LF) is targeted for elimination in Sierra Leone. Epidemiological coverage of mass drug administration (MDA) with ivermectin and albendazole had been reported >65% in all 12 districts annually. Eight districts qualified to implement transmission assessment survey (TAS) in 2013 but were deferred until 2017 due to the Ebola outbreak (2014–2016). In 2017, four districts qualified for conducting a repeat pre-TAS after completing three more rounds of MDA and the final two districts were also eligible to implement a pre-TAS.Methodology/Principal findingsFor TAS, eight districts were surveyed as four evaluation units (EU). A school-based survey was conducted in children aged 6–7 years from 30 clusters per EU. For pre-TAS, one sentinel and one spot check site per district (with 2 spot check sites in Bombali) were selected and 300–350 persons aged 5 years and above were selected. For both surveys, finger prick blood samples were tested using the Filariasis Test Strips (FTS).For TAS, 7,143 children aged 6–7 years were surveyed across four EUs, and positives were found in three EUs, all below the critical cut-off value for each EU. For the repeat pre-TAS/pre-TAS, 3,994 persons over five years of age were surveyed. The Western Area Urban had FTS prevalence of 0.7% in two sites and qualified for TAS, while other five districts had sites with antigenemia prevalence >2%: 9.1–25.9% in Bombali, 7.5–19.4% in Koinadugu, 6.1–2.9% in Kailahun, 1.3–2.3% in Kenema and 1.7% - 3.7% in Western Area Rural.Conclusions/SignificanceEight districts in Sierra Leone have successfully passed TAS1 and stopped MDA, with one more district qualified for conducting TAS1, a significant progress towards LF elimination. However, great challenges exist in eliminating LF from the whole country with repeated failure of pre-TAS in border districts. Effort needs to be intensified to achieve LF elimination.  相似文献   
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Background

1974–2005 studies across Sierra Leone showed onchocerciasis endemicity in 12 of 14 health districts (HDs) and baseline studies 2005–2008 showed lymphatic filariasis (LF) endemicity in all 14 HDs. Three integrated annual mass drug administration (MDA) were conducted in the 12 co-endemic districts 2008–2010 with good geographic, programme and drug coverage. Midterm assessment was conducted 2011 to determine impact of these MDAs on LF in these districts.

Methodology/Principal Findings

The mf prevalence and intensity in the 12 districts were determined using the thick blood film method and results compared with baseline data from 2007–2008. Overall mf prevalence fell from 2.6% (95% CI: 2.3%–3.0%) to 0.3% (95% CI: 0.19%–0.47%), a decrease of 88.5% (p = 0.000); prevalence was 0.0% (100.0% decrease) in four districts: Bo, Moyamba, Kenema and Kono (p = 0.001, 0.025, 0.085 and 0.000 respectively); and seven districts had reductions in mf prevalence of between 70.0% and 95.0% (p = 0.000, 0.060, 0.001, 0.014, 0.000, 0.000 and 0.002 for Bombali, Bonthe, Kailahun, Kambia, Koinadugu, Port Loko and Tonkolili districts respectively). Pujehun had baseline mf prevalence of 0.0%, which was maintained. Only Bombali still had an mf prevalence ≥1.0% (1.58%, 95% CI: 0.80%–3.09%)), and this is the district that had the highest baseline mf prevalence: 6.9% (95% CI: 5.3%–8.8%). Overall arithmetic mean mf density after three MDAs was 17.59 mf/ml (95% CI: 15.64 mf/ml–19.55 mf/ml) among mf positive individuals (65.4% decrease from baseline of 50.9 mf/ml (95% CI: 40.25 mf/ml–61.62 mf/ml; p = 0.001) and 0.05 mf/ml (95% CI: 0.03 mf/ml–0.08 mf/ml) for the entire population examined (96.2% decrease from baseline of 1.32 mf/ml (95% CI: 1.00 mf/ml–1.65 mf/ml; p = 0.000)).

Conclusions/Significance

The results show that mf prevalence decreased to <1.0% in all but one of the 12 districts after three MDAs. Overall mf density reduced by 65.0% among mf-positive individuals, and 95.8% for the entire population.  相似文献   
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Elephant populations are in decline across the African continent, but recent aerial surveys show that populations in Uganda are increasing. However, threats such as poaching and habitat disturbance remain. Having a comprehensive knowledge of the ranging behaviour of Ugandan elephants is crucial to understanding where critical habitat for the species occurs. We investigated various aspects of ranging behaviour of 45 radio-collared elephants (Loxodonta africana) in three areas—Queen Elizabeth Protected Area (QEPA), Murchison Falls (MFPA) Protected Area and Kidepo Valley (KVCA) Conservation Area. We also set Ugandan analyses in a continental context by comparison with home ranges reported in published literature. Elephants within KVCA had larger core ranges than elephants in QEPA or MFPA. Wet season ranges in KVCA were much larger than dry season ranges. The most important core areas in all three national parks were centred around water resources. Home range size was negatively correlated with net primary productivity (NPP) at Ugandan (N = 39 individuals) and continental (N = 17 sites) scales. This study indicates that, at a local scale, factors such as water source location are important in shaping elephant ranging behaviour. At larger scales, factors such as NPP are good predictors of elephant home range size.  相似文献   
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Applied Entomology and Zoology - The efficacy of mating disruption with Isonet®-T at the rate of 30, 45 or 60&nbsp;g a.i. ha –1 of sex pheromone to control Tuta absoluta (Meyrick)...  相似文献   
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The effect of salt stress, under glasshouse conditions, was studied on plant biomass, nodulation, and activities of acid phosphatases (APase, EC 3.1.3.2) and trehalose 6-phosphate phosphatase (TPP, EC 3.1.3.12) in the symbiosis common bean (Phaseolus vulgaris L.)-rhizobia nodules. Four common bean recombinant inbred lines (147, 115, 104 and 83) were separately inoculated, with CIAT 899 or RhM11 strains and grown in hydroaeroponic culture. Two NaCl levels (0 and 25 mM NaCl plant?1 week?1 corresponding, respectively, to the control and the salt treatment) were applied and the culture was assessed during 42 days after their transplantation. The results showed that the nodulation of these lines was not affected by salinity except for the line 83 inoculated with CIAT 899, whose nodule dry weight decreased by 48.24 % compared with the corresponding controls. For the other symbiotic combinations, shoot and root biomasses were not significantly affected by salt constraint. Salinity stress generally reduced acid phosphatise and trehalose phosphate phosphatase activities in nodules that were less affected in plants inoculated with RhM11. Based on our data, it appears that nodule phosphatase activity may be involved in salinity tolerance in common beans and the levels of salt tolerance depend principally on specific combination of the rhizobial strain and the host cultivar.  相似文献   
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