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1.
Lorenzo Zallocco Laura Giusti Maurizio Ronci Andrea Mussini Marco Trerotola Maria Rosa Mazzoni Antonio Lucacchini Laura Sebastiani 《International journal of molecular sciences》2021,22(9)
The autonomic nervous system (ANS) plays a crucial role both in acute and chronic psychological stress eliciting changes in many local and systemic physiological and biochemical processes. Salivary secretion is also regulated by ANS. In this study, we explored salivary proteome changes produced in thirty-eight University students by a test stress, which simulated an oral exam. Students underwent a relaxation phase followed by the stress test during which an electrocardiogram was recorded. To evaluate the effect of an olfactory stimulus, half of the students were exposed to a pleasant odor diffused in the room throughout the whole session. Saliva samples were collected after the relaxation phase (T0) and the stress test (T1). State anxiety was also evaluated at T0 and T1. Salivary proteins were separated by two-dimensional electrophoresis, and patterns at different times were compared. Spots differentially expressed were trypsin digested and identified by mass spectrometry. Western blot analysis was used to validate proteomic results. Anxiety scores and heart rate changes indicated that the fake exam induced anxiety. Significant changes of α-amylase, polymeric immunoglobulin receptor (PIGR), and immunoglobulin α chain (IGHA) secretion were observed after the stress test was performed in the two conditions. Moreover, the presence of pleasant odor reduced the acute social stress affecting salivary proteome changes. Therefore, saliva proteomic analysis was a useful approach to evaluate the rapid responses associated to an acute stress test also highlighting known biomarkers. 相似文献
2.
Perkins Kenneth A.; Ciccocioppo Melinda; Jacobs Lynette; Doyle Todd; Caggiula Anthony 《Canadian Metallurgical Quarterly》2003,11(4):269
Nonpharmacological cues associated with drug intake may influence subjective and reinforcing effects of those drugs. Social drinkers (N = 80) participated in 2 sessions in which they rated and then consumed ad lib their preferred beer (with participants blind to brand). Visual and olfactory stimuli were obscured during 1 session (blocked) and not obscured during the other (unblocked). Dependent measures included ratings of "liking", "want another", and "desire to drink"; subjective mood; and ad lib beer consumption (reinforcement). Most ratings and ad lib consumption were lower during the blocked versus the unblocked condition. There were no interactions of blockade condition with sex and no effect of blockade on mood. These findings show that nonpharmacological stimuli associated with alcohol consumption influence alcohol's subjective and reinforcing effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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4.
L. M. Schroeder 《Journal of chemical ecology》1992,18(9):1583-1593
The field response ofTomicus piniperda (L.) andHylurgops palliatus (Gyll.) (Coleoptera: Scolytidae) to the attractant ethanol in combination with volatile wood constituents released from the nonhost tree speciesPopulus tremula L. (Salicaceae) andBetula pendula Roth (Betulaceae) was studied using flight barrier traps. The attraction of both species decreased when aspen or birch wood was added to the ethanol bait. The same was true forRhizophagus depressus (F.) (Coleoptera: Rhizophagidae), a predatory species associated with conifer bark beetles.Glischrochilus quadripunctatus (L-),Epuraea bickhardti St.-Claire Deville,E. unicolor (Oliv.) (Coleoptera: Nitidulidae), andRhizophagus parvutus (Payk.) (Coleoptera: Rhizophagidae) were caught in higher numbers in traps baited with both ethanol and wood of aspen or birch than in traps baited with ethanol alone. In a separate experiment, landings ofT. piniperda andH. palliatus on nonhosts (black plastic tubes) were demonstrated with sticky traps. 相似文献
5.
通过对洛东水电厂的来水量、地质和经济指标等技术资料的分析,认为采用灯泡贯流式机组扩大其装机的容量是可行的。并介绍了洛东水电厂增机扩容的可行性设计情况。 相似文献
6.
灯泡贯流式发电机组直径小,转速低,发电机的通风冷却是一个难点。通过对京南、马骝滩、石面坦及南津渡等水电站的发电机运行过程中出现的温升过高,定子线棒绝缘受损等问题的分析,提出了解决的措施与改进方案,并对灯泡贯流式机组冷却系统的设计提出了建议,可供参考和借鉴。 相似文献
7.
Odors seem to be perceived differently when presented ortho- or retronasally. In this study, stimuli of controlled concentration and duration were applied in either the anterior nasal cavity or epipharynx by means of air-dilution olfactometry. Stimulus concentration was monitored in the olfactory cleft. In Experiment 1, odor thresholds to a food (chocolate) and a nonfood (lavender) odor were lower for orthonasal, compared with retronasal, stimulation. In Experiment 2, intensity ratings to suprathreshold odor concentrations were significantly higher for orthonasal than for retronasal stimulation with hydro- hydrogen sulfide, but not phenyl ethyl alcohol. Accordingly, amplitudes and latencies of olfactory event-related gen potentials to retronasal stimuli were found to be smaller and prolonged, respectively. This indicates differential processing of olfactory stimuli presented through the retronasal or orthonasal routes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
为了回答灯泡贯流泵装置中的灯泡体究竟应该前置还是应该后置的问题,应用水泵装置三维湍流数值模拟的方法分别研究了南水北调东线工程某泵站前置灯泡和后置灯泡贯流泵装置两个不同方案的流态,揭示了前置灯泡和后置灯泡贯流泵装置的基本流动属性;数值模拟的结果得到流道模型试验的验证。研究结果表明:前置灯泡贯流泵装置的进、出水流态均匀平顺,水力损失较小;后置灯泡贯流泵装置的进水流态均匀平顺,但出水流道内存在明显的偏流和旋涡流动,水力损失较大;灯泡体前置符合水力学的基本原理,是获得最佳灯泡贯流泵装置水力性能的必要条件之一。 相似文献
9.
Electroantennograms (EAGs) from male and femaleIps avulsus, I. calligraphus, andI. grandicollis to their pheromones and selected host odorants or kairomones verified the presence of antennal olfactory receptors in both sexes of each species capable of detecting ipsdienol, ipsenol,cis- andtrans-verbenol,endo-brevicomin -pinene, frontalin, and verbenone. Each species possesses receptors with lower thresholds and in greater abundance for the compounds they produce and to which they are behaviorally most responsive. Detection of bothIps andDendroctonus pheromones by the three cohabiting species provides a sensory basis for olfactory interactions among the species. Differences in both threshold and saturation levels for EAGs for the various behavioral chemicals could denote differences in specific behavioral roles for each compound.Texas Agricultural Experiment Station Paper Number TA-22463. This research was supported in part by McIntire-Stennis Project 1525, USDA-CR grants 85-CRCR-1-1856 and 86-CRCR-2019 and NATO Collaborative Research Grant 86-0710. The findings, opinions, and recommendations expressed herein are those of the authors and not necessarily those of the U.S. Department of Agriculture. All programs and information of the Texas Agricultural Experiment Station are available without regard to race, ethnic origin, religion, sex, or age.Mention of a trademark, proprietary product, or vendor does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture and does not imply its approval to the exclusion of other products or vendors that may also be suitable. 相似文献
10.
Campbell CA Cook FJ Pickett JA Pope TW Wadhams LJ Woodcock CM 《Journal of chemical ecology》2003,29(10):2225-2234
Gynoparous female and male damson-hop aphids, Phorodon humuli (Schrank), were caught in the field by water traps that were releasing the sex pheromone of this species, (1RS,4aR,7S,7aS)-nepetalactol. No behavioral activity was elicited by (4aS,7S,7aR)-nepetalactone, the major sex pheromone component of other aphid species such as Megoura viciae Buckton, even though olfactory cells were found in the secondary rhinaria on the third antennal segment of P. humuli that responded strongly to this compound. Gynoparous female P. humuli in the field responded less strongly to (1R,4aS,7S,7aR)-nepetalactol, the sex pheromone of the bird cherry-oat aphid, Rhopalosiphum padi (L.), than they did to the (4aR,7S,7aS)-nepetalactols, but males responded only to the latter. The (4aR,7S,7aS)-nepetalactone showed no electrophysiological activity so was not used in field trials. Releasing either the (4aS,7S,7aR)-nepetalactone or the (1R,4aS,7S,7aR)-nepetalactol with the (4aR,7S,7aS)-nepetalactols did not inhibit the response of P. humuli gynoparous females and males to the latter. Males of R. padi responded as strongly to the (4aR,7S,7aS)-nepetalactols as they did to (1R,4aS,7S,7aR)-nepetalactol. Males of P. humuli and R. padi responded positively to an increased concentration of the (4aR,7S,7aS)-nepetalactols released from two vials compared with that from a single vial, as did P. humuli (in one of two experiments) and R. padi to the (1RS,4aR,7S,7aS)- and (1R,4aS,7S,7aR)-nepetalactols when released together. 相似文献