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31.
Trail pheromones mediate communication among western subterranean termites, Reticulitermes hesperus Banks. Repetitive passages of ≥28 termites were required to establish a pheromone trail and trails needed to be reinforced
because they lasted <48 hr. The minimal threshold concentration for inducing responses from termite workers and secondary
reproductives was between 0.01 and 0.1 fg/cm of (3Z,6Z,8E)-dodecatrien-1-ol (henceforth, dodecatrienol). Workers showed optimal trail-following behavior to dodecatrienol at a concentration
of 10 fg/cm. Trails with concentrations >10 pg/cm were repellent to workers. Workers did not detect pheromone gradients, responding
equally to increasing or decreasing gradients of dodecatrienol, and termite workers were not able to differentiate between
different concentrations of dodecatrienol. Termites preferred dodecatrienol trails to 2-phenoxyethanol trails. Antennae played
a key role in trail pheromone perception. Dodecatrienol acted as an arrestant for worker termites (10 fg/cm2) and male alates (5 ng/cm2), whereas sternal gland extracts from females attracted male alates. Workers and alates, upon contact with filter paper disks
treated with higher doses (10 fg/cm2 and 5 ng/cm2, respectively) of dodecatrienol, were highly excited (increased antennation and palpation) and repeatedly returned to the
treated disks. Dodecatrienol did not act as a phagostimulant when offered on a paper towel disk. Reticulitermes hesperus is highly responsive to dodecatrienol, and it may play an important role in orientation of workers and alates. 相似文献
32.
The sex pheromone of Hemileuca eglanterina from the San Gabriel Mountains, California, was determined to be a combination of E10,Z12-hexadeca-10,12-dien-1-yl acetate, E10,Z12-hexadeca-10,12-dien-1-ol, and E10,Z12-hexadeca-10,12-dienal. Ratios of the compounds in extracts of female pheromone glands varied around a mean of 100 : 48 : 1.1 of the acetate, alcohol, and aldehyde, respectively. Field trials with synthetic compounds indicated that the optimum ratio of alcohol to aldehyde was 10 : 1 and that this ratio was more critical than the ratio of either compound to the acetate. A synthetic blend of 100 : 10 : 1 acetatendash;alcoholndash;aldehyde was effective at attracting male moths in the field. Additional compounds found in both extract and aeration samples failed to significantly increase trap catches of male moths, although some of these minor components elicited responses from male moth antennae in coupled gas chromatography–electroantennography studies. 相似文献
33.
Jocelyn C. Prez-Lara Enrique Espinosa Leopoldo Santos-Argumedo Hctor Romero-Ramírez Gabriela Lpez-Herrera Fabio García-García Claudia Sandoval-Montes Vianney Ortiz-Navarrete Mnica Flores-Muoz Juan C. Rodríguez-Alba 《International journal of molecular sciences》2021,22(21)
CD38 is a transmembrane glycoprotein expressed by T-cells. It has been reported that patients with systemic lupus erythematosus (SLE) showed increased CD38+CD25+ T-cells correlating with immune activation and clinical signs. Contrariwise, CD38 deficiency in murine models has shown enhanced autoimmunity development. Recent studies have suggested that CD38+ regulatory T-cells are more suppressive than CD38− regulatory T-cells. Thus, we have suggested that CD38 overexpression in SLE patients could play a role in regulating immune activation cells instead of enhancing it. This study found a correlation between CD38 with FoxP3 expression and immunosuppressive molecules (CD69, IL-10, CTLA-4, and PD-1) in T-cells from lupus-prone mice (B6.MRL-Faslpr/J). Additionally, B6.MRL-Faslpr/J mice showed a decreased proportion of CD38+ Treg cells regarding wild-type mice (WT). Furthermore, Regulatory T-Cells (Treg cells) from CD38-/- mice showed impairment in expressing immunosuppressive molecules and proliferation after stimulation through the T-cell receptor (TCR). Finally, we demonstrated an increased ratio of IFN-γ/IL-10 secretion in CD38-/- splenocytes stimulated with anti-CD3 compared with the WT. Altogether, our data suggest that CD38 represents an element in maintaining activated and proliferative Treg cells. Consequently, CD38 could have a crucial role in immune tolerance, preventing SLE development through Treg cells. 相似文献
34.
Holden RM Beseau D Booth SL Adams MA Garland JS Morton RA Collier CP Foley RN 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(1):53-58
Fibroblast growth factor 23 (FGF-23) is elevated in patients with end-stage kidney disease and has been linked with mortality, vascular calcification, markers of bone turnover, and left ventricular hypertrophy. In this cohort study, we determined the correlates of FGF-23 (including cardiac troponin T [cTNT]) and determined its association with mortality over 3.5 years of follow-up in 103 prevalent hemodialysis patients. Mean age was 61.2 (15.5) and the mean dialysis vintage was 4.19 years (4.6). The median (interquartile range) FGF-23 was 1259 (491, 2885) RU/mL. Independent predictors (estimate standard error) of log-transformed FGF-23 concentrations included phosphorus (0.75 [0.237], P = 0.002) and cardiac troponin T (1.04 [0.41], P = 0.01). There were 57 deaths. In the fully adjusted model, the significant predictors of mortality included age and albumin. The independent association between FGF-23 and cTNT is a novel finding. Whether this relationship supports the possibility that a downstream effect of dysregulated phosphorous homeostasis may be enhanced cardiac remodeling requires further study. 相似文献
35.
Charnas Jocelyn W.; Hilsenroth Mark J.; Zodan Jennifer; Blais Mark A. 《Canadian Metallurgical Quarterly》2010,47(4):484
The Personality Assessment Inventory (PAI) and the Rorschach were used to investigate differences between patients who withdrew early from university-based outpatient psychodynamic psychotherapy and those who continued in treatment. The study employs two sets of analyses, one utilizing the complete sample (N = 101) and a second comprised of comparison pairs matched on the specific therapist delivering treatment (n = 36 for Rorschach; n = 38 for PAI). It was hypothesized that early withdrawers would score higher on the PAI Treatment Rejection Scale (RXR) and the PAI Treatment Process Index (TPI) than treatment continuers. It was also hypothesized that early treatment withdrawers will have better overall interpersonal relationships, less need for closeness and intimacy, less available psychological resources and more current stimulus demands, and lower levels of psychological/cognitive disturbance as measured by the Rorschach. In addition, differences between the two groups on PAI treatment and clinical scales and subscales were examined. Results indicated that PAI RXR differentiated between the two groups (p 相似文献
36.
Marcello Tammaro William A. Mauro Jocelyn Bonjour Rita M. A. Mastrullo Rémi Revellin 《传热工程》2013,34(13):1124-1132
This article presents 154 pressure drop data points measured during two-phase flow of R-134a in horizontal return bends. The tube diameter is constant at 10.85 mm and the curvature ratio is either 7.74 or 5.53. Saturation temperature varies from 15 to 20°C, vapor quality from 0.05 and 0.95, and mass velocity ranges from 300 to 600 kg m?2 s?1. Return bend pressure drops are calculated by subtracting the straight tube pressure drop from the total measured pressure drop along the bend. The perturbations induced up- and downstream of the singularity are taken into account in the measurements. The comparison of the pressure drops for the two configurations (curvature ratio of 5.53 and 7.74) showed that they are greater (about 10%) for the larger curvature ratio. This can be attributed to the effect of the developed length on the pressure drop; on the other side the pressure gradients are larger for the lower curvature ratio, which can be explained by the effect of the centrifugal force and the perturbations up- and downstream of the return bend. The experimental data are compared against four prediction methods available in the literature. The Domanski and Hermès correlation is the best at predicting the present data. 相似文献
37.
The aim of this paper is to present an extension of the original non-intrusive radioactive particle tracking method (RPT) to any geometries with irregular moving boundaries. The principal advantage of RPT over other non-intrusive methods is that it enables the visualization of rather large systems. However, the underlying reconstruction algorithm is limited to cylindrically shaped systems such as fluidized beds and columns. It excludes a wide variety of systems involving multiphase flows such as, for instance, spherical reactors, cyclones and powder silos, hoppers and blenders, all of which are thus currently out of reach of current RPT capabilities. This work addresses these limitations and proposes an approach that solves the inverse map problem to reconstruct the tracer position with time by using a mesh of unstructured cells to discretize the system geometry and kinematics. The anisotropy induced by the gas-solid interface is discussed and taken into account in the proposed model. To show the possibilities and assess the performance of the developed technique, the flow of particles in a 16-qt V-blender is mapped and the mean velocity field is computed. 相似文献
38.
Bernard K Tarabalka Y Angulo J Chanussot J Benediktsson JA 《IEEE transactions on image processing》2012,21(4):2008-2021
In this paper, a new method for supervised hyperspectral data classification is proposed. In particular, the notion of stochastic minimum spanning forest (MSF) is introduced. For a given hyperspectral image, a pixelwise classification is first performed. From this classification map, M marker maps are generated by randomly selecting pixels and labeling them as markers for the construction of MSFs. The next step consists in building an MSF from each of the M marker maps. Finally, all the M realizations are aggregated with a maximum vote decision rule in order to build the final classification map. The proposed method is tested on three different data sets of hyperspectral airborne images with different resolutions and contexts. The influences of the number of markers and of the number of realizations M on the results are investigated in experiments. The performance of the proposed method is compared to several classification techniques (both pixelwise and spectral-spatial) using standard quantitative criteria and visual qualitative evaluation. 相似文献
39.
Maki EC Rodstein J Millar JG Barbour KS Hanks LM Barbour JD 《Journal of chemical ecology》2011,37(7):714-716
Earlier work has shown that adult male Prionus californicus Motschulsky (Coleoptera: Cerambycidae) are attracted to the female-produced compound (3R,5S)-3,5-dimethyldodecanoic acid, and to a synthetic mixture of the four stereoisomers of 3,5-dimethyldodecanoic acid. Here, we report the results of field trials that tested whether or not three structurally related compounds (methyl 3,5-dimethyldodecanoate, 3,5-dimethyltridecanoic acid, and 3,5-dimethylpentadecanoic acid), present in extracts of virgin females, are attractive, and whether or not they influence attraction to 3,5-dimethyldodecanoic acid. In a trial with single components, only traps baited with the acid or its methyl ester captured more beetles than did control traps; catches to the acid were five times higher than to the methyl ester. Another trial, excluding 3,5-dimethyldodecanoic acid, confirmed the activity of the methyl ester. Finally, addition of the three compounds to 3,5-dimethyldodecanoic acid, in the ratio found in extracts from female beetles, gave a catch similar to that of traps baited with 3,5-dimethyldodecanoic acid alone. Consequently, the function of these minor compounds remains undetermined. 相似文献
40.
A. Jocelyn Prof. A. Kar A. Fanourakis T. Flower M. Ackerman A. Keevil J. Way 《Materialwissenschaft und Werkstofftechnik》2009,40(8):601-605
The process of Superplastic Forming (SPF) has produced a vast number of components, from simple shapes to those with complex geometric features, all to a dimensional accuracy difficult to obtain by traditional sheet metal methods. When used in conjunction with Diffusion Bonding (DB), extraordinarily lightweight, stiff, strong and fatigue enduring components and structures can be manufactured that are virtually impossible to produce by any other means. However, SPF/DB is often criticised as too complicated, expensive, slow and unstable, a reputation that has contributed to its use being largely confined to manufacturing when no other means of production can be found. Perhaps, the fundamental cause of this negative perception of SPF/DB is the fact that derivatives of mid 18th century hydraulic presses are used, virtually universally, that provide only a single temperature to the work piece, which is heated primarily through conduction, a form of heating which is slow and expensive. By comparison, modern, electrically efficient, lasers, if used to directly heat the work piece, could transform SPF/DB into a mainstream process and the first choice of designers. This paper compares, and contrasts, the two systems. 相似文献