Factors influencing the human intestinal flora

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Review of established methods in event research

In reviewing 165 of the most prominent event articles this paper provides a timely evaluation of prevalent research methods that have shaped event research in the past 16 years. We adopt critical case sampling and citation analysis approaches to identify 21 journals and the 165 articles. We subsequently analysed the content of each article to reveal the method(s) used and classified these by journal and by year. To facilitate discussion about the findings, the paper initially appraises the character of the event phenomenon and the implications of this for methods selection. This discussion portrays a largely social and contingent character to events that presents specific requirements to researchers seeking to interrogate it. The discussion pinpoints key considerations that should shape event researchers decisions about their selection of methods. The findings reveal a preponderance of survey based approaches and also very limited adoption of multiple methods. The findings also indicate a less prominent, but growing, application of subjectivist oriented approaches such as interviews, indicating a progressive trend that is discussed as being more favourable to the character of the subject matter. Ultimately we provide six precepts that emerge from this study, to signpost key considerations for event researchers as our discipline moves beyond the early stages of its development toward a more mature phase. Keywords: Event research, Research methods, Survey, Interviews, Focus groups, Observatio

Metallicity in the Galactic Center: The Arches cluster

We present a quantitative spectral analysis of five very massive stars in the Arches cluster, located near the Galactic center, to determine stellar parameters, stellar wind properties and, most importantly, metallicity content. The analysis uses a new technique, presented here for the first time, and uses line-blanketed NLTE wind/atmosphere models fit to high-resolution near-infrared spectra of late-type nitrogen-rich Wolf-Rayet stars and OfI+ stars in the cluster. It relies on the fact that massive stars reach a maximum nitrogen abundance that is related to initial metallicity when they are in the WNL phase. We determine the present-day nitrogen abundance of the WNL stars in the Arches cluster to be 1.6% (mass fraction) and constrain the stellar metallicity in the cluster to be solar. This result is invariant to assumptions about the mass-luminosity relationship, the mass-loss rates, and rotation speeds. In addition, from this analysis, we find the age of the Arches cluster to be 2-2.5Myr, assuming coeval formation

Contribution of Harman and Norharman to the Reinforcing Efficacy of Aqueous Tobacco Smoke Extract Self-Administered by Rats

Background: Animal models of drug abuse treat nicotine as the primary reinforcing agent that promotes tobacco addiction. However, rodents demonstrate poor self-administration of nicotine despite evidence of tobacco's high abuse potential in humans. This discrepancy has been attributed to other constituents of tobacco smoke that facilitate the development of nicotine dependence. Objectives: This study aimed to determine whether rats would self-administer intravenous an aqueous tobacco smoke extract (TPM) to find evidence if it was more reinforcing than nicotine alone. The study also evaluated the role of tobacco smoke constituent’s harman and norharman in any differences observed. Methods: Firstly, male Sprague-Dawley rats (n=29) were assigned to treatment groups: nicotine (30.0μg/kg/infusion), TPM (containing 30.0μg/kg/infusion nicotine) or saline vehicle. Ability for each treatment to support intravenous self-administration was assessed using spontaneous acquisition of responding on gradually increasing fixed ratio schedules (FR1, FR2, FR5). Subsequent progressive ratio (PR) testing was employed to determine reinforcing efficacy of each treatment. Then a second group of rats (N = 56) were assigned to treatment groups: nicotine alone (30.0 or 75.0μg/kg/infusion) or nicotine combined with norharman (0, 0.4, 2.5 or 6.25μg/kg/infusion) and harman (0.0, 1.6 or 10.0μg/kg, IP), and tested using a similar protocol. Results: Animals readily acquired self-administration responding for TPM and produced higher PR breakpoints (BP) than rats treated with nicotine alone or vehicle. Rats trained to respond for a larger dose of nicotine demonstrated significantly greater response rates than those receiving the lower dose of nicotine. Finally, the addition of harman and norharman to nicotine significantly reduced BP at the lower unit dose of nicotine tested. Conclusions: These findings support the hypothesis that TPM is more reinforcing than nicotine alone. However, the increased reinforcing efficacy of TPM cannot be attributed to the actions of harman and norharman. The potential role of serotonin inhibition in tobacco reward processes is discussed

Developmental trends in voice onset time: some evidence for sex differences

This study reports on an investigation into the voice onset time (VOT) patterns of the plosives /p b t d/ in a group of 30 children aged 7 (n = 10), 9 (n = 10) and 11 (n = 10) years. Equal numbers of girls and boys participated in the study. Each child named a series of letter objects to elicit /p b t d/ in a syllable onset position with a fixed vowel context. VOT data were examined for age, sex and plosive differences with the following hypotheses: Firstly, that there would be sex differences in the VOT patterns of preadolescent children. Secondly, that the sex differences in VOT patterns would be linked to age and development, and that these would eventually become marked by the age of 11 years, by which time adult-like VOT values should have been achieved. Finally, that the extent of sex and age differences would be dependent upon the plosive being investigated. Results indicated patterns of decrease with age in the VOT values of /p b/ for the boys, with some evidence of increases in the VOT values of /t/ for the girls. In addition, 'voiced' and 'voiceless' cognates showed a more marked bimodal distribution in the girls' VOT patterns. This bimodal distribution was investigated by examining the degree of difference between the VOT values of voiced and voiceless cognate pairs /p b/ and /t d/, and examining the effects of age, sex and cognate pair. These results indicated that more marked sex differences in the 'voiced'/'voiceless' contrast emerged between the data of the 9- and 11-year-olds, a pattern, which was more marked for the alveolar plosives. These preliminary results confirmed all three hypotheses. The findings are presented and discussed both within a developmental and sociophonetic framework

Kinematic Leg Therapy Device

ME450 Capstone Design and Manufacturing Experience: Fall 2015This project’s sponsor, Dr. Ben Dwamena, was a young aspiring engineering student in Ghana until he was encouraged down the medical path in his early schooling. Dr. Dwamena has no use of his legs and needs a wheelchair to move about. There are many downsides that are associated from this type of physical assistance: bed sores, muscle atrophy, poor blood circulation, kidney stones, and urinary health issues. Dr. Dwamena was able to purchase a standup wheelchair that helps with a few of these ailments, but he wanted to create a better wheelchair. To improve blood circulation, decrease muscle atrophy, and lessen the chances of bed sores, Dr. Dwamena asked the University of Michigan to create an automated leg moving device that would work in his stand up wheelchair. The device would mimic a stand-still walking motion while he is in the standing position in his wheelchair. This would help with all the alignments listed above. The objective of this project was to provide a more accessible and user friendly method of kinesiotherapy for individuals without the use of their legs.http://deepblue.lib.umich.edu/bitstream/2027.42/117340/1/ME450-F15-Project23-FinalReport.pd

Dementia Inpatient Study on The Recognition and Evaluation of Signs Signalling Emotional Distress - DISTRESSED

Dementia is a common comorbidity in older people admitted to general hospital. People with dementia have a high prevalence of psychological symptoms, pain and delirium, which if left untreated can cause distress and predispose the person to worse outcomes. Identifying individual symptoms or the causes of distress can be difficult because people with more severe dementia often struggle to communicate. Systems are in place to help healthcare professionals recognise and treat individual symptoms, but they require the user to be able to apply and use them appropriately. This thesis describes the development and feasibility testing of a novel screening tool, which aims to improve distress recognition for dementia patients in a hospital setting. Initially, to understand areas of unmet need, a retrospective review of 116 case notes of people with dementia admitted to hospital was undertaken. The results suggested a discrepancy between observed and expected psychological symptoms, delirium, and pain, and that existing systems used to identify and manage them were underutilised. It was hypothesised that encouraging healthcare professionals to identify distress, rather than specific symptoms, may be a simple and sensitive method for improving the recognition of psychological symptoms, pain and delirium downstream. However, how hospital healthcare professionals identify distress in dementia patients was previously undescribed. Existing methods were explored using thematic analysis of 25 semi-structured interviews with healthcare professionals who regularly care for people with dementia. The participants interviewed all believed they could innately identify distress. However, common facilitators and barriers to this process were identified including: how the patient presents, familiarity with the patient, using the person’s usual community carer as a source of information, staff training, ward culture, and competing ward priorities. Following a series of design phases, the themes generated were combined with existing theories on implementing healthcare interventions to develop a novel distress screening tool, for use by healthcare professionals to assess dementia patients in a hospital setting. The Distress Recognition Tool (DRT), was deliberately simple and designed to complement existing hospital physical observation systems. As part of the assessment, community carers for the person with dementia are also asked to contribute to the process when visiting the ward. The DRT was further refined using feedback from focus groups comprising healthcare professionals and community carers of people with dementia. To test the use, usefulness and potential mechanistic impacts of the DRT, the tool was feasibility tested during the routine care of 32 consented patients with dementia admitted to a large teaching hospital. All staff on participating wards received DRT training and consequently the tool was used on average 0.9 times per participant day. Carers contributed to the assessment process on average 0.4 times per patient day. The feedback from healthcare professionals and community carers was positive but highlighted that more complex aspects of the DRT need refinement