A prospective evaluation of the long-term clinical associations of neurocardiovascular instability in older people

PhD ThesisIntroduction Neurocardiovascular instability (NCVI) describes a group of disorders characterised by orthostatic hypotension (OH), carotid sinus hypersensitivity (CSH) and autonomic dysfunction. In cross-sectional studies, NCVI has been associated with cognitive impairment, depression and falls. It is suggested that episodic hypotension causes cerebral hypoperfusion, which in turn causes anoxic brain damage. White matter hyperintensities (WMH) on MRI are thought to represent ischaemic damage due to hypoperfusion and are also associated with cognitive impairment, depression, and falls. Despite these observations, the long-term clinical significance of NCVI remains unclear, particularly in asymptomatic individuals Aims To examine the associations between NCVI and cognition, depression and falls over a ten-year follow-up To examine the association between NCVI and WMH volume on MRI To examine the association between NCVI and ten-year all-cause mortality. Methods Participants were recruited from an established cohort of people aged ≥65 years in 2002. Baseline evaluation of neurocardiovascular function in 2002 included heart rate variability, autonomic function tests and carotid sinus massage. Neuropsychological assessment was performed at baseline and at follow-up. MRI was performed at follow-up (but not at baseline). WMH volume was calculated using FLAIR MRI. Cox regression analysis was used to examine the association between NCVI and mortality. Results In 2002 1000 individuals aged ≥65 years were selected at random from a single GP practice and invited to participate in the study. 353 consented to enrolment in the baseline study. Of whom 104 individuals [median age 79 years (range 74-92)] participated in the year 10 follow-up. Asymptomatic NCVI was not associated with cognition, depression, falls or WMH volume at follow-up. Symptomatic OH was associated with greater decline in CAMCOG memory score [B =1.19, P<0.05] and symptomatic CSH was independently associated with increased WMH volume [P<0.01]. NCVI defined according to standard criteria was not associated with ten-year mortality. However, at baseline it had been identified that the 95th percentile for systolic vasodepression was 76.6 mmHg and the 95th percentile for RR interval post CSM was 7.3 seconds. These thresholds were used to define CSH modified criteria. CSH defined according to modified criteria, derived from the baseline populations’ response to CSM, was associated with increased mortality [HR2.37, P=0.02]. Conclusions NCVI is not associated with adverse outcomes at ten years in asymptomatic older people but symptomatic NCVI is associated with decline in memory and greater WMH volume, suggesting symptoms are of prognostic significance. Modified CSH criteria are better predictors of ten-year mortality than current criteria.Research into Ageing Fund: Age UK: The British Geriatric Society: NIHR Newcastle Biomedical Research Centre

Herbivory in Antarctic fossil forests and comparisons with modern analogues in Chile

During the Tertiary (-50 million years ago) forests were present in Antarctica, but fossil evidence of insect life in the forests is rare. Extensive fossil floras from Antarctica contain evidence of insect herbivory on the leaves; these provide indirect evidence of past insect life. Such preservation of the behaviour of insects (insect trace fossil) can be used to examine the diversity of insects that lived in the forests of Antarctica in the past. Palaeogene (65 Ma - 35 Ma) fossil floras from two localities on the Antarctic Peninsula (King George Island and Seymour Island) were examined for the presence of insect trace fossils. Fossil leaves were preserved as impressions and compressions within siltstones and sandstones and represent leaves that were preserved within a quiet lake environment (King George Island) or shallow marine setting (Seymour Island). The floras were dominated by leaf morphotypes that resemble modem Nothofagaceae (Southern beeches), but leaves similar to other Southern Hemisphere families were also present, including the Cunoniaceae, Proteaceae and Lauraceae. Over 2,000 fossil leaves were examined for traces of past insect activity. Over 150 fossil leaves (6.9%) contained evidence of feeding traces on the leaves (54 trace types from King George Island and 19 from Seymour Island). The trace fossils were grouped into four functional feeding types: general leaf chewing, skeleton feeding, leaf mines and leaf galls. General leaf chewing was the most common trace type at both localities and leaf mines the least common. The nearest living analogues of the Antarctic Palaeogene forests are the Valdivian and Magellanic forests of Chile and so insect activity in these forests was studied in order to understand past insect activity in Antarctica. The diversity of insect traces in the Chilean forests was investigated at six sites within National Parks, covering a latitudinal range between 37°S and 55°S. Insects associated with two deciduous species, Nothofagus pumilio and Nothofagus antarctica, were of particular focus. The factors that affected the level of insect damage and the proportion of leaf mines and galls included height within the tree, orientation of leaf within the tree, altitude, season, leaf age, latitude, plant species and insect species. Insects which created similar general leaf chewing traces in the modem forests in Chile similar to those on the fossil leaves were larvae of Lepidoptera (Geometridae), Hymenoptera (Symphyta) and the larvae and adults of Coleoptera (Chrysomelidae, Curculionidae, Cerambycidae). Leaf mines were created by species of Coleoptera and Hymenoptera. Species of Diptera (Cecidomyiidae) and Hymenoptera (Cynipidae) created leaf galls. Other invertebrates (Acari (Eriophyidae) and Nematoda (Tylenchid)) also created leaf galls in Chile, similar to fossil leaf galls from Antarctica. Herbivory types on the fossil flora from King George Island were most similar to modem types in Puyehue (a northern study site, Chile) and those from Seymour Island were most similar to Torres in the south, indicating a possible climatic control on their distribution. Based on this relationship, estimates of palaeoclimate of Antarctica suggest that the climate of King George Island to the west of the Peninsula was warmer and wetter (3.5°C -lO.4°C mean annual temperature, 3.5°C - 24.3°C maximum and minimum mean monthly temperature and 1500 mm annual precipitation) than the cooler and more stable environment at Seymour Island to the east (3.5°C -lO.4°C mean annual temperature, -0.4°C -16°C maximum and minimum mean monthly temperature, and 570 mm annual precipitation). The studies of fossil and modem insect traces in Antarctica and Chile have provided a unique opportunity to reconstruct past insect life of Antarctica during the Palaeogene. This is the first documented evidence of insect life during the Palaeogene on Antarctica and highlights the value of modem analogue comparisons to obtain a greater insight into past insect ecology

Underpinning excellence in higher education – an investigation into the leadership, governance and management behaviours of high-performing academic departments.

The changes in government funding alongside external pressures of increased international and national competition have meant that higher education institutions need to excel in a turbulent environment. The leadership, governance and management (LGM) of academic departments are key concerns. This study investigates the correlation between behaviours, attitudes and competencies at a department level and overall departmental performance in terms of hard data measures. The research question this paper seeks to address is: what are the LGM behaviours that are associated with high-performance in academic departments? More than 600 people across 50 academic departments in 5 UK universities were surveyed through the use of three research phases consisting of open-ended questionnaires, critical case sampled semi-structured interviews and a fixed-response survey. Synthesising the data and findings of the study revealed a thematic framework of eight broad themes that contribute to excellence in academic departments. These were in the areas of change management, research and teaching, communication, strategy and shared values, leadership, departmental culture, rewards and staffing. The behaviours associated with each of these themes were used to construct the Underpinning Excellence model

Air pollution disasters: liability issues in negligence associated with the provision of Personal Protective Interventions (facemasks)

Disasters may impact air quality through the generation of high levels of potentially pathogenic particulate matter (PM), for example, in a volcanic eruption. Depending on the concentrations of particles in the air, their size and composition, and the duration of exposure, high levels of PM can create significant public health issues. It has been argued that air pollution, in and of itself, is a public health crisis. One possible intervention to reduce exposure to high levels of PM during an air pollution disaster (APD) is using facemasks. However, agencies may be reluctant to recommend or distribute facemasks for community use during APDs for a variety of reasons, including concerns about liability. There has been no analysis of these concerns. This paper analyzes whether agencies may have a legal duty of care in negligence to provide warnings about the health risks associated with APDs and/or to recommend facemasks as a protective mechanism for community use to reduce exposure to PM. It is also the first to examine the potential for liability in negligence, when a decision is made to distribute facemasks for community use during an APD and the receiver alleges that they sustained a personal injury and seeks compensation

Understanding of Management Guidelines in Patients with Lynch Syndrome

Lynch syndrome is an autosomal dominant hereditary cancer syndrome with relatively high prevalence. It is estimated that more than one million Americans have Lynch syndrome, and more than 95% have not been identified. Identification of these individuals is important so that measures can be taken for prevention or early detection of associated cancers. No existing studies assess how well individuals with Lynch syndrome understand these guidelines; some prior studies have assessed adherence to colonoscopies, the recommendation with the most evidence, with mixed results. The purpose of this study was to survey adults with a diagnosis of Lynch syndrome, to assess their understanding of and adherence to management guidelines and to learn about their experiences with healthcare providers and any barriers to following guidelines. A survey was distributed through two Lynch syndrome advocacy groups, Lynch Syndrome International and AliveAndKickn, via Facebook, Twitter, and email listservs. The survey had 312 responses; 278 of those responses met eligibility criteria and were analyzed. Most participants had above average education and household income. More than 70% of respondents indicated they had a colonoscopy in the past 12 months, and more than 95% understood they should have colonoscopies at least every two years. This survey provides a starting point for research surrounding education and understanding of medical management guidelines for individuals with Lynch syndrome. While the results indicate a high understanding of and adherence to management guidelines, the non-representative demographics may limit the generalizability of the study findings. Future studies should aim to assess a more representative sample of individuals with Lynch syndrome, and consider how best to educate and increase access to genetic counseling and education for newly diagnosed individuals. The identification of more individuals with Lynch syndrome is an important public health genetics goal in order to increase surveillance in this group and decrease morbidity and mortality associated with cancer; attempts to achieve this goal should include a plan to educate and increase access to care for those with a new diagnosis

Poor sleep quality and progression of gait impairment in an incident Parkinson’s disease cohort

Abnormal sleep may associate with cognitive decline in Parkinson's disease (PD). Furthermore, sleep dysfunction may associate with worse motor outcome. We hypothesised that PD patients with poor quality sleep would have greater progression in gait dysfunction, due to structural and functional overlap in networks subserving sleep and gait regulation. 12 PD patients and 12 age-matched controls completed longitudinal follow-up over 36 months. Poor sleep efficiency and greater sleep fragmentation correlated significantly with progression of step-width variability, a gait characteristic mediated by postural control, providing evidence that poor sleep in PD is associated with a more rapid deterioration in gait

Biodiversity benefits of an ecosystem engineer are negated by an invasive predator

Ecosystem engineers play a vital role in community assembly by modifying the environment to create novel habitat features. Woodrats (Neotoma sp.) build and maintain intricate stick-nests that stockpile organic materials and create habitat for other small species. The Key Largo woodrat (Neotoma floridana smalli) is an endangered subspecies endemic to Key Largo, Florida, USA, that has undergone substantial declines due to habitat loss and predation by invasive predators. We leveraged data from a camera trap monitoring grid at supplemental woodrat nest structures to survey bird communities to evaluate the role of woodrat nest use and stick-nest building related to bird abundance using generalized linear models. We predicted that woodrat occurrence and stick-nest building would positively correlate with bird species richness and abundance due to the creation of habitat structures that support prey for birds. To test this, we analyzed the relationship that bird abundance and species richness have with several indicators of woodrat activity along with other environmental and predator variables. Bird abundance was positively associated with woodrat supplemental nest use and stick-nest building. However, these positive associations were largely negated by the presence of free-roaming cats (Felis catus), an invasive predator, and dampened by proximity to human development. We provide evidence that woodrats may have cascading effects on their local food webs by creating foraging grounds for birds, but this positive relationship is disrupted by the presence of an introduced predator

Mapping Khayelitsha: The complexities of everyday policing in a high crime area

In order for a single South African police station to operate optimally, or indeed at any level of functionality at all, it is required to form cooperative relations with a host of external institutions. This is in addition to ensuring that the internal structural capacity of a police station is maintained. The Commission of Inquiry into Allegations of Police Inefficiency and a Breakdown in Relations between SAPS and the Community in Khayelitsha identified shortcomings in both internal structures and the functioning of external relations. Here, we provide an overview of the stakeholders that make up the policing web in Khayelitsha. This forms the basis for clearer understandings of on-the-ground policing in this unsafe and violent neighbourhood

Faster decline of pitch memory over time in congenital amusia

Congenital amusia (amusia, hereafter) is a developmental disorder that impacts negatively on the perception of music. Psychophysical testing suggests that individuals with amusia have above average thresholds for detection of pitch change and pitch direction discrimination; however, a low-level auditory perceptual problem cannot completely explain the disorder, since discrimination of melodies is also impaired when the constituent intervals are suprathreshold for perception. The aim of the present study was to test pitch memory as a function of (a) time and (b) tonal interference, in order to determine whether pitch traces are inherently weaker in amusic individuals. Memory for the pitch of single tones was compared using two versions of a paradigm developed by Deutsch (1970a). In both tasks, participants compared the pitch of a standard (S) versus a comparison (C) tone. In the time task, the S and C tones were presented, separated in time by 0, 1, 5, 10, and 15 s (blocked presentation). In the interference task, the S and C tones were presented with a fixed time interval (5 s) but with a variable number of irrelevant tones in between: 0, 2, 4, 6, and 8 tones (blocked presentation). In the time task, control performance remained high for all time in tervals, but amusics showed a performance decrement over time. In the interference task, controls and amusics showed a similar performance decrement with increasing number of irrelevant tones. Overall, the results suggest that the pitch representations of amusic individuals are less stable and more prone to decay than those of matched non-amusic individuals