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991.
992.
Our understanding of the role of cuticular hydrocarbons (CHC) in recognition is based largely on temperate ant species and honey bees. The stingless bees remain relatively poorly studied, despite being the largest group of eusocial bees, comprising more than 400 species in some 60 genera. The Meliponini and Apini diverged between 80–130 Myr B.P. so the evolutionary trajectories that shaped the chemical communication systems in ants, honeybees and stingless bees may be very different. The aim of this study was to study if a unique species CHC signal existed in Neotropical stingless bees, as has been shown for many temperate species, and what compounds are involved. This was achieved by collecting CHC data from 24 colonies belonging to six species of Melipona from North-Eastern Brazil and comparing the results with previously published CHC studies on Melipona. We found that each of the eleven Melipona species studied so far each produced a unique species CHC signal based around their alkene isomer production. A remarkable number of alkene isomers, up to 25 in M. asilvai, indicated the diversification of alkene positional isomers among the stingless bees. The only other group to have really diversified in alkene isomer production are the primitively eusocial Bumblebees (Bombus spp), which are the sister group of the stingless bees. Furthermore, among the eleven Neotropical Melipona species we could detect no effect of the environment on the proportion of alkane production as has been suggested for some other species.  相似文献   
993.
Tabit  Kamal  Hajjou  Hanaa  Waqif  Mohamed  Saâdi  Latifa 《SILICON》2021,13(2):327-334
Silicon - In the present study, coal fly ash was used as the main starting material (80.74 wt.%) in the production of the cordierite-based ceramics by benefiting from its high contents of...  相似文献   
994.
BACKGROUND: This research derives from the French national multisite collaborative study on the clinical epidemiology of mania (EPIMAN). Our aim is to establish the validity of dysphoric mania along a "spectrum of mixity" extending into mixed mania with subthreshold depressive manifestations; to demonstrate the feasibility of obtaining clinically meaningful data on this entity on a national level; and to characterize the contribution of temperamental attributes and gender in its origin. METHODS: EPIMAN involves training 23 French psychiatrists in four different sites, representing four regions of France; to rigorously apply a common protocol deriving from the criteria of DSM-IV and McElroy et al.; the use of such instruments as the Beigel-Murphy, Ahearn-Carroll, modified HAM-D; and measures of affective temperaments based on the Akiskal-Mallya criteria; obtaining data on comorbidity, and family history (according to Winokur's approach as incorporated into the FH-RDC); and prospective follow-up for at least 12 months. The present report concerns the clinical and temperamental features of 104 manic patients during the acute hospital phase. RESULTS: Dysphoric mania (DM defined conservatively with fullblown depressive admixtures of five or more symptoms) occurred in 6.7%; the rate of dysphoric mania defined broadly (DM, presence of > or = 2 depressive symptoms) was 37%. Depressed mood and suicidal thoughts had the best positive predictive values for mixed mania. In comparison to pure mania (0-1 depressive symptoms), DM was characterized by female over-representation; lower frequency of such typical manic symptomatology as elation, grandiosity, and excessive involvement; higher prevalence of associated psychotic features; higher rate of mixed states in first episodes; and complex temperamental dysregulation along primarily depressive, but also cyclothymic, and irritable dimensions; such irritability was particularly apparent in mixed mania at the lowest threshold of depressive admixtures of two symptoms only. LIMITATION: In a study involving hospitalized affectively unstable psychotic patients, it was difficult to assure that psychiatrists making the clinical diagnoses would be blind to the temperamental measures. However, bias was minimized by the systematic and/or semi-structured nature of all evaluations. CONCLUSIONS: Mixed mania, defined cross-sectionally by the simultaneous presence of at least two depressive symptoms, represents a prevalent and clinically distinct form of mania. Subthreshold depressive admixtures with mania actually appear to represent the more common expression of dysphoric mania. Moreover, an irritable dimension appears to be relevant to the definition of the expression of mixed mania with the lowest threshold of depressive symptoms. Neither an extreme, nor an endstage of mania, "mixity" is best conceptualized as intrusion of mania into its "opposite" temperament - especially that defined by lifelong depressive traits - and favored by female gender. These data suggest that reversal from a temperament to an episode of "opposite" polarity represents a fundamental aspect of the dysregulation that characterizes bipolar disorder. In both men and women with hyperthymic temperament, there appears "protection" against depressive symptom formation during a manic episode which, accordingly, remains relatively "pure". Because men have higher rates of this temperament, pure mania is overrepresented in men; on the other hand, the depressive temperament in manic women seems to be a clinical marker for the well-known female tendency for depression, hence the higher prevalence of mixed mania in women.  相似文献   
995.
In a variety of research fields, including linguistics, human–computer interaction research, psychology, sociology and behavioral studies, there is a growing interest in the role of gestural behavior related to speech and other modalities. The analysis of multimodal communication requires high-quality video data and detailed annotation of the different semiotic resources under scrutiny. In the majority of cases, the annotation of hand position, hand motion, gesture type, etc. is done manually, which is a time-consuming enterprise requiring multiple annotators and substantial resources. In this paper we present a semi-automatic alternative, in which the focus lies on minimizing the manual workload while guaranteeing highly accurate annotations. First, we discuss our approach, which consists of several processing steps such as identifying the hands in images, calculating motion of the hands, segmenting the recording in gesture and non-gesture events, etc. Second, we validate our approach against existing corpora in terms of accuracy and usefulness. The proposed approach is designed to provide annotations according to the McNeill (Hand and mind: what gestures reveal about thought, University of Chicago Press, Chicago, 1992) gesture space and the output is compatible with annotation tools such as ELAN or ANVIL.  相似文献   
996.
Illiteracy is often associated with people in developing countries. However, an estimated 50 % of adults in a developed country such as Canada lack the literacy skills required to cope with the challenges of today’s society; for them, tasks such as reading, understanding, basic arithmetic, and using everyday items are a challenge. Many community-based organizations offer resources and support for these adults, yet overall functional literacy rates are not improving. This is due to a wide range of factors, such as poor retention of adult learners in literacy programs, obstacles in transferring the acquired skills from the classroom to the real life, personal attitudes toward learning, and the stigma of functional illiteracy. In our research we examined the opportunities afforded by personal mobile devices in providing learning and functional support to low-literacy adults. We present the findings of an exploratory study aimed at investigating the reception and adoption of a technological solution for adult learners. ALEX© is a mobile application designed for use both in the classroom and in daily life in order to help low-literacy adults become increasingly literate and independent. Such a solution complements literacy programs by increasing users’ motivation and interest in learning, and raising their confidence levels both in their education pursuits and in facing the challenges of their daily lives. We also reflect on the challenges we faced in designing and conducting our research with two user groups (adults enrolled in literacy classes and in an essential skills program) and contrast the educational impact and attitudes toward such technology between these. Our conclusions present the lessons learned from our evaluations and the impact of the studies’ specific challenges on the outcome and uptake of such mobile assistive technologies in providing practical support to low-literacy adults in conjunction with literacy and essential skills training.  相似文献   
997.
This study evaluated the effects of a ketogenic diet (KD) based on extra virgin coconut oil (Cocos nucifera L., VCO), on the treatment of epileptic rats. Two sets of experiments were conducted. First, male Wistar rats underwent induction of status epilepticus (SE) with the administration of pilocarpine intraperitoneally 21 animals reached spontaneous recurrent seizures (SRS) and were randomly allocated to the dietary regimens and video‐monitored for 19 days. In the second experiment, 24 animals were randomized immediately after the induction of SE and followed for 67 days. Diets were as follows: Control (AIN‐93G; 7% lipid), KetoTAGsoya (KD based on soybean oil; 69.79% lipid), and KetoTAGcoco (KD based on VCO; 69.79% lipid). There were no differences in the latency to the first crisis, total frequency, and duration of the SRS between groups in 2 experiments. The data suggest no effects of KD, with or without VCO, in rats with pilocarpine‐induced epilepsy.  相似文献   
998.
In ball-cratering wear tests, two abrasive wear modes are commonly observed, grooving abrasion and rolling abrasion, which act in distinct areas. Observing this tendency, the aim of this article is to discuss the characterization of an intermediate condition, in which the superposition of the grooving and the rolling abrasive wear modes is observed. This phenomenon is referred to as microrolling abrasion due to the following particular characteristic: the rolling abrasion was found to act on the grooving abrasion. Additionally, in a defined sliding distance range and normal force range, microrolling abrasion is qualitatively observed to be proportional to the sliding distance and inversely proportional to the normal force.  相似文献   
999.
Asphaltenes which differ in their abilities to form water/oil emulsions were analysed by acidimetry, infrared and nuclear magnetic resonance spectroscopies. Asphaltenes which easily form such emulsions are loosely packed molecules and exhibit a marked acid/base imbalance.  相似文献   
1000.
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