Stereotypy, personality and environmental enrichment

A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, October 2015.Animals in captivity are often raised in suboptimal environments, which lead to abnormal behaviours, such as stereotypic behaviour. Environmental enrichment can reduce or eliminate these behaviours to some extent. However, enrichments are not always successful in their intended purpose, which may be attributed to differences among individuals (i.e. personality). The overarching aim of my study was to investigate how environmental enrichment affected the expression of stereotypic behaviour in my study model, the African striped mouse, Rhabdomys dilectus, and to ascertain whether personality modulated the responses to enrichment. I conducted four experiments to test these aims. Firstly, I tested whether personality was associated with the development and expression of stereotypic behaviours. Results indicated that stereotypic striped mice were bold and showed a proactive coping style, while non-stereotypic striped mice were less bold and showed a reactive coping style. Furthermore, having a proactive coping style did not predict the onset of stereotypic behaviours. Nevertheless, individual differences in personality were observed even within stereotypic and non-stereotypic striped mice so that each group was not homogeneous for personality. Secondly, I tested whether personality was associated with the responses of stereotypic striped mice to enrichment. While stereotypic behaviours were reduced in enriched cages, individuals were not consistent in their behaviour, indicating flexible behavioural responses to the different cage complexities. Interestingly, these responses occurred irrespective of personality differences. There were no treatment-related differences in the behavioural responses of non-stereotypic striped mice. Thirdly, I examined whether the age at which striped mice were introduced to the environmental enrichment influenced their behavioural responses. Age did not affect the behavioural responses of stereotypic or non-stereotypic mice to the cages of different complexity. Surprisingly, while stereotypic behaviours were reduced in the enriched treatments, not all stereotypic mice responded to enrichment in the same manner, implying flexible behavioural responses. Moreover, these behavioural responses also occurred regardless of the individual’s personality type. There were no age-related differences in the behavioural responses of non-stereotypic striped mice. Finally, I investigated the purpose of wheel running, either as an enrichment or as a re-directed stereotypic behaviour, in stereotypic striped mice, because there is much debate about its use as an enrichment. Due to individual differences in responses to the running wheel, wheel running appeared to be both an enrichment and a re-directed behaviour. In conclusion, my study provides the first empirical data for the theory that stereotypic animals have different personalities to non-stereotypic animals. Nonetheless, this dichotomy between stereotypic and non-stereotypic striped mice at the group level masked individual responses within groups, with individuals flexibly altering their behaviour, depending on the environment to which they were exposed, which in turn affected the efficacy of environmental enrichment. My study suggests that the welfare and well-being of animals requires an assessment of individual trajectories in the development of stereotypic behaviours

Some Characterized Projective δ-cover

In this paper we characterize some properties of projective δ-cover and find some new results with δ-supplemented module M. Let M be a fixed R-module. A δ-cover in M is an δ-small epimorphism from M onto P.Thes concept introduce by Zhou [14]. A δ-cover is projective δ-cover( M-projective δ-cover) in case M is projective. Keywords: Singular, non singular, simple, small, δ-small, cover, δ-cover, supplement, δ-supplement

Demographic profile of patient with acute watery diarrhea during monsoon 2022: Patan Hospital, Nepal

Introduction: Diarrhea is the passage of three or more loose or liquid stools per day or more. Acute watery diarrhea is a major public health problem worldwide.  In Nepal, diarrhea is among the top 10 inpatient morbidity. This study’s objective is to monitor demographic characteristics and laboratory findings of stool specimens of diarrhea. Method: This is a cross-sectional descriptive study done at Patan Hospital. Ethical approval was taken from the Ethical committee. Data for Monsoon 2022 (June to September 2022) were collected from the Patan Hospital record system. Cases from within the Lalitpur district were included. Result: Out of 119 cases, 50(42%) were male and 69(58%) were female. The mean age±SD was 33.28±25.38 (p=0.083) with maximum cases observed during June and a peak observed during the fourth week of June. Out of 119, 4(3.3%) were stool culture positive. Two cases of Vibrio cholera, one case of Shigella sonnei, and one case of Salmonella parathypi B were isolated. In the etiological profile, 14 Entamoeba histolytica were isolated. Conclusion: During the outbreak of diarrhea in Monsoon 2022, adults were affected most. The culture of acute watery diarrhea showed two cases of Vibrio cholera

Response of different electron beam melting produced Alloy 718 microstructures to thermal post-treatments

Electron beam melting (EBM) was used to produce Alloy 718 specimens with different microstructures (columnar, equiaxed and a combination thereof) by varying the process parameters. The present study aimed at assessing the response of such varying as-built microstructures to identical thermal post-treatments, which included hot isostatic pressing (HIPing) followed by heat treatment involving solution treatment and aging. The effect of these treatments on defect content, grain structure, hardness and phase constitution in the specimens was specifically analysed. Despite differences in defect content of as-built specimens with distinct microstructures, HIPing was effective in closing defects leading to samples exhibiting similar density. After HIPing, grains with equiaxed morphology or columnar grains with lower aspect ratio showed higher tendency for grain growth in comparison to the columnar grains with higher aspect ratio. The various factors affecting the stability of grains during HIPing of builds with distinct microstructures were investigated. These factors include texture, grain size, and secondary phase particles. The carbide sizes in the different as-built samples varied but were found to be largely unaffected by the post-treatments. Solution treatment following HIPing led to greater precipitation of grain boundary δ phase in regions with coarser grains than the smaller ones. After HIPing and heat treatment, all specimens exhibited similar precipitation of γ″ phase regardless of their grain morphology in the as-built condition

Aftermath of pulmonary tuberculosis : computed tomography assessment

Purpose: Pulmonary tuberculosis (PTB) has clinically significant sequelae, even after recommended treatment completion. It is important to recognise these sequelae for accurate assessment of severity and treatment planning, if indicated. Material and methods: We retrospectively analysed contrast-enhanced computed tomography (CT) scans of chest of 100 patients with previous history of treated pulmonary tuberculosis, excluding those with active pulmonary disease. CT findings were analysed based on parenchymal, airway, pleural, mediastinal, and vascular sequelae of PTB. Results: Parenchymal sequelae included fibrosis with architectural distortion and volume loss (90%), cavities (21%) (with aspergillomas noted in 19% of these cases), and tuberculomas (54%). Airway involvement was noted as bronchiectasis (77%) and bronchial stenosis (4%) but none with broncholithiasis. Mediastinal sequelae included lymph node calcification (74%), fibrosing mediastinitis (1%), and pericardial tuberculosis (2%). Pleural sequelae included pleural thickening (22%), with 40.9% of these patients showing calcifications, and one patient with chronic chylous pleural effusion. Vascular sequelae included Rasmussen aneurysms (4%), enlarged bronchial arteries (3%), and systemic bronchial collaterals in 1% of our patients. Conclusions: PTB has multiple appalling sequelae, which require due attention and appropriate treatment in symptomatic cases. Radiological evaluation forms an integral part in patient assessment and decision making

As-Built and Post-treated Microstructures of an Electron Beam Melting (EBM) Produced Nickel-Based Superalloy

The microstructures of an electron beam melted (EBM) nickel-based superalloy (Alloy 718) were comprehensively investigated in as-built and post-treated conditions, with particular focus individually on the contour (outer periphery) and hatch (core) regions of the build. The hatch region exhibited columnar grains with strong 〈001〉 texture in the build direction, while the contour region had a mix of columnar and equiaxed grains, with no preferred crystallographic texture. Both regions exhibited nearly identical hardness and carbide content. However, the contour region showed a higher number density of fine carbides compared to the hatch. The as-built material was subjected to two distinct post-treatments: (1) hot isostatic pressing (HIP) and (2) HIP plus heat treatment (HIP + HT), with the latter carried out as a single cycle inside the HIP vessel. Both post-treatments resulted in nearly an order of magnitude decrease in defect content in hatch and contour regions. HIP + HT led to grain coarsening in the contour, but did not alter the microstructure in the hatch region. Different factors that may be responsible for grain growth, such as grain size, grain orientation, grain boundary curvature and secondary phase particles, are discussed. The differences in carbide sizes in the hatch and contour regions appeared to decrease after post-treatment. After HIP + HT, similar higher hardness was observed in both the hatch and contour regions compared to the as-built material

Student Engagement Detection Using Emotion Analysis, Eye Tracking and Head Movement with Machine Learning

With the increase of distance learning, in general, and e-learning, in particular, having a system capable of determining the engagement of students is of primordial importance, and one of the biggest challenges, both for teachers, researchers and policy makers. Here, we present a system to detect the engagement level of the students. It uses only information provided by the typical built-in web-camera present in a laptop computer, and was designed to work in real time. We combine information about the movements of the eyes and head, and facial emotions to produce a concentration index with three classes of engagement: "very engaged", "nominally engaged" and "not engaged at all". The system was tested in a typical e-learning scenario, and the results show that it correctly identifies each period of time where students were "very engaged", "nominally engaged" and "not engaged at all". Additionally, the results also show that the students with best scores also have higher concentration indexes.Comment: 9 pages, 9 Figures, 2 table

Residual stress determination by neutron diffraction in powder bed fusion-built Alloy 718: Influence of process parameters and post-treatment

Alloy 718 is a nickel-based superalloy that is widely used as a structural material for high-temperature applications. One concern that arises when Alloy 718 is manufactured using powder bed fusion (PBF) is that residual stresses appear due to the high thermal gradients. These residual stresses can be detrimental as they can degrade mechanical properties and distort components. In this work, residual stresses in PBF built Alloy 718, using both electron and laser energy sources, were measured by neutron diffraction. The effects of process parameters and thermal post-treatments were studied. The results show that thermal post-treatments effectively reduce the residual stresses present in the material. Moreover, the material built with laser based PBF showed a higher residual stress compared to the material built with electron-beam based PBF. The scanning strategy with the lower amount of residual stresses in case of laser based PBF was the chessboard strategy compared to the bi-directional raster strategy. In addition, the influence of measured and calculated lattice spacing (d0) on the evaluated residual stresses was investigated