60 research outputs found
The effects of lithium on reticulo-rumen motility of sheep and goats
Lithium salts are used experimentally to induce food aversions and as a marker for measuring the intake of supplements (Ralphs, 1992)
The good, the bad and the implicit: a comprehensive approach to annotating explicit and implicit sentiment
We present a fine-grained scheme for the annotation of polar sentiment in text, that accounts for explicit sentiment (so-called private states), as well as implicit expressions of sentiment (polar facts). Polar expressions are annotated below sentence level and classified according to their subjectivity status. Additionally, they are linked to one or more targets with a specific polar orientation and intensity. Other components of the annotation scheme include source attribution and the identification and classification of expressions that modify polarity. In previous research, little attention has been given to implicit sentiment, which represents a substantial amount of the polar expressions encountered in our data. An English and Dutch corpus of financial newswire, consisting of over 45,000 words each, was annotated using our scheme. A subset of this corpus was used to conduct an inter-annotator agreement study, which demonstrated that the proposed scheme can be used to reliably annotate explicit and implicit sentiment in real-world textual data, making the created corpora a useful resource for sentiment analysis
Automatic Detection of Cyberbullying in Social Media Text
While social media offer great communication opportunities, they also
increase the vulnerability of young people to threatening situations online.
Recent studies report that cyberbullying constitutes a growing problem among
youngsters. Successful prevention depends on the adequate detection of
potentially harmful messages and the information overload on the Web requires
intelligent systems to identify potential risks automatically. The focus of
this paper is on automatic cyberbullying detection in social media text by
modelling posts written by bullies, victims, and bystanders of online bullying.
We describe the collection and fine-grained annotation of a training corpus for
English and Dutch and perform a series of binary classification experiments to
determine the feasibility of automatic cyberbullying detection. We make use of
linear support vector machines exploiting a rich feature set and investigate
which information sources contribute the most for this particular task.
Experiments on a holdout test set reveal promising results for the detection of
cyberbullying-related posts. After optimisation of the hyperparameters, the
classifier yields an F1-score of 64% and 61% for English and Dutch
respectively, and considerably outperforms baseline systems based on keywords
and word unigrams.Comment: 21 pages, 9 tables, under revie
Modulation of leukocyte hsp70 expression by gender, menstrual cycle phase and oral contraceptives
Echinacea induced hsp70 alterations in leukocytes
Heat shock proteins (hsp) are expressed constitutively as well as induced in response to mild stress. These stress factors include inflammation, viral and bacterial infection, oxidative stress and cytotoxins. Altered hsp expression has been found in a number of disease states. Echinacea is used as a prophylactic to boost the immune system and has been previously shown to enhance hsp70 expression in leucocytes after mild heat shock. In this study, the effects of echinacea supplementation on hsp70 expression in the different leucocyte subpopulations has been examined. Twenty four healthy volunteers aged between 20 and 66 years with a body mass index ranging from 20.2 to 30.7 participated in the study. They consumed 2 echinacea tablets (4.42mg total alkylamides per tablet) twice a day for 14 days. Blood samples were taken on days 1 and 15 and hsp70 expression was determined by flow cytometry in whole blood with and without in vitro heat shock. Significant differences were observed in the percentage of several white cell subsets that expressed hsp70. CD4 and CD8 lymphocytes expressed significantly more hsp70 in both males and females after supplementation but in natural killer cells and B lymphocytes, expression of hsp70 were only significantly increased in the male participant cohort. These results indicate that Echinacea may play a role in activating the immune system when the body encounters a challenge such as a virus
The Reproductive Physiology of Leptin
Leptin is a 16kDa protein hormone thought to regulate energy homeostasis and circulates at levels corresponding to fat mass and acute changes in the nutritional status. Leptin has been proposed as a metabolic mediator linking nutritional status with the reproductive axis in mammals and leptin receptors have been identified in hypothalamic areas regulating feeding behavior and reproductive processes. Leptin may be involved in indicating the reproductive system that adequate energy stores are available for normal reproductive functions. In addition, leptin has been shown to regulate maturation of the reproductive system, gonadotropin secretion, onset of puberty, gonadal function, embryonic development and implantation, fetal development, pregnancy and parturition. Recent studies have shown that low levels of leptin exert a stimulatory effect on the reproductive system whereas higher levels are inhibitory. This biphasic effect of leptin has been demonstrated in number of physiological systems. To further confirm this hypothesis, the present thesis was aimed to study effect of leptin on female reproduction following lowering/neutralization of leptin levels in the circulation or blocking its action in vivo. In this thesis, it is reported for the first time that administration of anti-leptin or anti-leptin receptor antiserum in vivo exerts significant positive effects on various reproductive processes in female mice including ovarian follicular development, ovulation, embryonic implantation and pregnancy. These results provide new evidence that leptin signaling plays multiple important roles in mouse reproduction
Dietary restriction has a differential effect on plasma leptin concentrations in fat and lean sheep
Hair cortisol concentration differs across site and person: localisation and consistency of responses to a brief pain stressor
Although in vitro studies have shown that cortisol concentrations in human and animal hair respond to environmental stressors, few data have been reported regarding the in vivo variability of hair cortisol to brief pain stressors. As an extension of a previous study, hair was collected and assayed for cortisol concentrations from each of three sites (elbow, mid-forearm, wrist) before and after participants immersed their hand in ice water for 1 min. Results showed that the 'localization' boundary of hair cortisol responses previously reported was able to be reduced to only 250 mm between sites. Furthermore, all participants showed considerable variability in hair cortisol across the three sites at each collection period, although consistency across participants in overall responsivity of hair cortisol to the pain stressor was observed
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