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71.
Elwin G. Smith Rosemarie A. De Clerck-Floate Brian H. Van Hezewijk James R. Moyer Eva Pavlik 《Biological Control》2009,48(3):281-286
The cost of rearing the root-feeding weevil, Mogulones cruciger Herbst, to control the invasive weed houndstongue (Cynoglossum officinale L.) was determined for two managed production methods. Production in an insectary setting provides control over rearing and all adult weevils that emerge can be collected, but required facility investment and high labor input. Mass-rearing in a managed ‘field crop’ setting required less facilities and labor while the insects were multiplying, but capture of the emerged adults was challenging and labor intensive. Estimated per adult weevil production costs were $CDN 2.65 for the insectary approach, and from $CDN 0.10 to $CDN 0.14 for mass-rearing in the managed field crop setting. Even though collection of adult weevils in the field crop production system was challenging, commercial production of M. cruciger should consider use of this mass-rearing method because of its lower cost. 相似文献
72.
A methodological issue in research relating daytime mood to dream content is the question of whether mood congruency effects—that is, recalling more negative events if the current mood is more negative—also play a role in the dream recall process. This study adopted an indirect approach by testing the hypothesis that interindividual differences in mood congruency effects in a memory task carried out in the daytime correlate with mood congruency effects in dream recall (recalling more negative dream emotions, as one would predict on the basis of the current stress level or overall mood state). The findings, however, did not support the hypothesis of mood congruency effects and, thus, rule out that the findings regarding the continuity hypothesis of dreaming are biased by selective recall. Studies with different methodological approaches are necessary to validate this study’s findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
74.
Salama-Cohen P Arévalo MA Grantyn R Rodríguez-Tébar A 《Journal of neurochemistry》2006,97(5):1269-1278
We have previously shown that dendrite morphology of cultured hippocampal neurones is controlled by Notch receptor activation or binding of nerve growth factor (NGF) to its low affinity receptor p75NTR, i.e. processes that up-regulate the expression of the Homologue of enhancer of split 1 and 5. Thus, the increased expression of these genes decreases the number of dendrites, whereas abrogation of Homologue of enhancer of split 1/5 activity stimulates the outgrowth of new dendrites. Here, we show that Neurogenin 3 is a proneural gene that is negatively regulated by Homologue of enhancer of split 1/5. It also influences dendrite morphology. Hence, a deficit of Notch or NGF/p75NTR activation can lead to the production of high levels of Neurogenin 3, which stimulates the outgrowth of new dendrites. Conversely, activation of either Notch or p75NTR depressed Neurogenin 3 expression, which not only decreased the number of dendrites but also favoured inhibitory (GABAergic) synaptogenesis, thereby diminishing the ratios of excitatory/inhibitory inputs. NGF also augmented the levels of mRNA encoding the vesicular inhibitory amino acid transporter, but it did not affect the fraction of GAD65/67-positive neurones. Conversely, overexpression of Neurogenin 3 largely reduced the number of inhibitory synaptic contacts and, consequently, produced a strong increase in the ratios of excitatory/inhibitory synaptic terminals. Our results reveal a hitherto unknown contribution of NGF/p75NTR to dendritic and synaptic plasticity through Neurogenin 3 signalling. 相似文献
75.
Boyden ED Campos-Xavier AB Kalamajski S Cameron TL Suarez P Tanackovic G Tanackovich G Andria G Ballhausen D Briggs MD Hartley C Cohn DH Davidson HR Hall C Ikegawa S Jouk PS König R Megarbané A Nishimura G Lachman RS Mortier G Rimoin DL Rogers RC Rossi M Sawada H Scott R Unger S Valadares ER Bateman JF Warman ML Superti-Furga A Bonafé L 《American journal of human genetics》2011,(6):767-772
Spondyloepimetaphyseal dysplasia with joint laxity, leptodactylic type (lepto-SEMDJL, aka SEMDJL, Hall type), is an autosomal dominant skeletal disorder that, in spite of being relatively common among skeletal dysplasias, has eluded molecular elucidation so far. We used whole-exome sequencing of five unrelated individuals with lepto-SEMDJL to identify mutations in KIF22 as the cause of this skeletal condition. Missense mutations affecting one of two adjacent amino acids in the motor domain of KIF22 were present in 20 familial cases from eight families and in 12 other sporadic cases. The skeletal and connective tissue phenotype produced by these specific mutations point to functions of KIF22 beyond those previously ascribed functions involving chromosome segregation. Although we have found Kif22 to be strongly upregulated at the growth plate, the precise pathogenetic mechanisms remain to be elucidated. 相似文献
76.
Gonella E Negri I Marzorati M Mandrioli M Sacchi L Pajoro M Crotti E Rizzi A Clementi E Tedeschi R Bandi C Alma A Daffonchio D 《Applied and environmental microbiology》2011,77(4):1423-1435
One emerging disease of grapevine in Europe is Bois noir (BN), a phytoplasmosis caused by "Candidatus Phytoplasma solani" and spread in vineyards by the planthopper Hyalesthes obsoletus (Hemiptera: Cixiidae). Here we present the first full characterization of the bacterial community of this important disease vector collected from BN-contaminated areas in Piedmont, Italy. Length heterogeneity PCR and denaturing gradient gel electrophoresis analysis targeting the 16S rRNA gene revealed the presence of a number of bacteria stably associated with the insect vector. In particular, symbiotic bacteria detected by PCR with high infection rates in adult individuals fell within the "Candidatus Sulcia muelleri" cluster in the Bacteroidetes and in the "Candidatus Purcelliella pentastirinorum" group in the Gammaproteobacteria, both previously identified in different leafhoppers and planthoppers. A high infection rate (81%) was also shown for another symbiont belonging to the Betaproteobacteria, designated the HO1-V symbiont. Because of the low level of 16S rRNA gene identity (80%) with the closest relative, an uncharacterized symbiont of the tick Haemaphysalis longicornis, we propose the new name "Candidatus Vidania fulgoroideae." Other bacterial endosymbionts identified in H. obsoletus were related to the intracellular bacteria Wolbachia pipientis, Rickettsia sp., and "Candidatus Cardinium hertigii." Fluorescent in situ hybridization coupled with confocal laser scanning microscopy and transmission electron microscopy showed that these bacteria are localized in the gut, testicles, and oocytes. As "Ca. Sulcia" is usually reported in association with other symbiotic bacteria, we propose that in H. obsoletus, it may occur in a bipartite or even tripartite relationship between "Ca. Sulcia" and "Ca. Purcelliella," "Ca. Vidania," or both. 相似文献
77.
Gillian A. Lowe Garth Lipps Roger C. Gibson Sharon Halliday Amrie Morris Nelson Clarke Rosemarie N. Wilson 《PloS one》2014,9(4)
Background
Past research suggests that perceived neighbourhood conditions may influence adolescents'' emotional health. Relatively little research has been conducted examining the association of perceived neighbourhood conditions with depressive symptoms among Caribbean adolescents. This project examines the association of perceived neighbourhood conditions with levels of depressive symptoms among adolescents in Jamaica, the Bahamas, St. Kitts and Nevis, and St. Vincent.Methods
Adolescents attending grade ten of the academic year 2006/2007 in Jamaica, the Bahamas, St. Vincent, and St. Kitts and Nevis were administered the Neighbourhood Characteristics Questionnaire along with the BDI-II. Social cohesion, attachment to the neighbourhood, neighbourhood quality, neighbourhood crime, and neighbourhood disorder scales were created by summing the relevant subscales of the Neighbourhood Characteristics Questionnaire. Multiple regression analyses were used to examine the relationships of perceived neighbourhood conditions to depressive symptoms.Results
A wide cross-section of tenth grade students in each nation was sampled (n = 1955; 278 from Jamaica, 217 from the Bahamas, 737 St. Kitts and Nevis, 716 from St. Vincent; 52.1% females, 45.6% males and 2.3% no gender reported; 12 to 19 years, mean = 15.3 yrs, sd = .95 yr). Nearly half (52.1%) of all adolescents reported mild to severe symptoms of depression with 29.1% reporting moderate to severe symptoms of depression. Overall, Jamaican adolescents perceived their neighbourhoods in a more positive manner than those in the Bahamas, St. Vincent and St. Kitts and Nevis. Results of a series of hierarchical multiple regression analyses suggested that a different pattern of neighbourhood factors for each island were associated with depressive symptoms. However, neighbourhood factors were more highly associated with depressive symptoms for Jamaican students than for students in the other three islands.Conclusions
Neighbourhood factors appear to be partially associated with adolescents'' self-reports of depressive symptoms. However, other factors may mitigate this relationship. 相似文献78.
Andrew A. Crowl Evgeny Mavrodiev Guilhem Mansion Rosemarie Haberle Annalaura Pistarino Georgia Kamari Dimitrios Phitos Thomas Borsch Nico Cellinese 《PloS one》2014,9(4)
Background
The Campanuloideae (Campanulaceae) are a highly diverse clade of angiosperms found mostly in the Northern Hemisphere, with the highest diversity in temperate areas of the Old World. Chloroplast markers have greatly improved our understanding of this clade but many relationships remain unclear primarily due to low levels of molecular evolution and recent and rapid divergence. Furthermore, focusing solely on maternally inherited markers such as those from the chloroplast genome may obscure processes such as hybridization. In this study we explore the phylogenetic utility of two low-copy nuclear loci from the pentatricopeptide repeat gene family (PPR). Rapidly evolving nuclear loci may provide increased phylogenetic resolution in clades containing recently diverged or closely related taxa. We present results based on both chloroplast and low-copy nuclear loci and discuss the utility of such markers to resolve evolutionary relationships and infer hybridization events within the Campanuloideae clade.Results
The inclusion of low-copy nuclear genes into the analyses provides increased phylogenetic resolution in two species-rich clades containing recently diverged taxa. We also obtain support for the placement of two early diverging lineages (Jasione and Musschia-Gadellia clades) that have previously been unresolved. Furthermore, phylogenetic analyses of PPR loci revealed potential hybridization events for a number of taxa (e.g., Campanula pelviformis and Legousia species). These loci offer greater overall topological support than obtained with plastid DNA alone.Conclusion
This study represents the first inclusion of low-copy nuclear genes for phylogenetic reconstruction in Campanuloideae. The two PPR loci were easy to sequence, required no cloning, and the sequence alignments were straightforward across the entire Campanuloideae clade. Although potentially complicated by incomplete lineage sorting, these markers proved useful for understanding the processes of reticulate evolution and resolving relationships at a wide range of phylogenetic levels. Our results stress the importance of including multiple, independent loci in phylogenetic analyses. 相似文献79.
Background
Patients with a diagnosis of schizophrenia are socially excluded. The aim of this study was to investigate how patients participate in first encounters with unfamiliar healthy participants, who are unaware of their diagnosis.Methods
Patterns of participation were investigated during interactions involving three-people. Three conversation roles were analysed: (i) speaker, (ii) primary recipient- focus of the speaker’s attention and (iii) secondary recipient- unaddressed individual. Twenty patient interactions (1 patient, 2 healthy controls) and 20 control interactions (3 healthy participants) were recorded and motion captured in 3D. The participation of patients and their partners, in each conversation role, was compared with controls at the start, middle and end of the interaction. The relationship between patients’ participation, their symptoms and the rapport others experienced with them was also explored.Results
At the start of the interaction patients spoke less (ß = −.639, p = .02) and spent more time as secondary recipient (ß = .349, p = .02). Patients’ participation at the middle and end of the interaction did not differ from controls. Patients’ partners experienced poorer rapport with patients who spent more time as a primary recipient at the start of the interaction (Rho(11) = −.755, p<.01). Patients’ participation was not associated with symptoms.Conclusion
Despite their increased participation over time, patients’ initial participation appears to be associated with others’ experience of rapport with them. Thus, the opening moments of patients’ first encounters appear to be interpersonally significant. Further investigation of patient and others’ behaviour during these critical moments is warranted in order to understand, and possibly develop interventions to address, the difficulties schizophrenia patients experience here. 相似文献80.
Lauren Kurek Maya L. Najarian David A. Cremers Rosemarie C. Chinni 《Journal of visualized experiments : JoVE》2013,(79)
The dependence of some LIBS detection capabilities on lower pulse energies (<100 mJ) and timing parameters were examined using synthetic silicate samples. These samples were used as simulants for soil and contained minor and trace elements commonly found in soil at a wide range of concentrations. For this study, over 100 calibration curves were prepared using different pulse energies and timing parameters; detection limits and sensitivities were determined from the calibration curves. Plasma temperatures were also measured using Boltzmann plots for the various energies and the timing parameters tested. The electron density of the plasma was calculated using the full-width half maximum (FWHM) of the hydrogen line at 656.5 nm over the energies tested. Overall, the results indicate that the use of lower pulse energies and non-gated detection do not seriously compromise the analytical results. These results are very relevant to the design of field- and person-portable LIBS instruments. 相似文献