Behaviour of brown bears (Ursus arctos) when repeatedly approached by humans on foot

Knowledge about encounters between humans and wildlife is important for conservation, management and policymaking, as well as for reducing conflict and negative interactions. There is general concern that an increased number of encounters might reduce wildlife flight responses. I investigated the responses of GPS-collared brown bears (Ursus arctos) in southcentral Sweden when repeatedly encountering humans on foot. Brown bears are generally wary of humans, and I therefore hypothesized that their behavioural response would not change with the number of experimental encounters. Bears were approached by observers 2 – 3 times per week for 2 – 4 weeks. The observers simulated recreational forest users during the approach and passed the bear’s initial location on an average distance of 29 m. A total of 11 solitary females (7 subadults and 4 adults) and 14 solitary males (6 subadults and 8 adults) were subject to an average of 6.6 approaches (SD = 1.19). I analysed flight response as distance between bear and observer when bear flight initiation (FID) occurred, the distance fled and time spent active after disturbance, combined with measurements of horizontal cover at the bear’s initial location. Data was analysed using generalized linear mixed-effect models with bear individual as random effect. No significant relationships were found between the number of approaches conducted on an individual and flight response. FID could best be explained by horizontal cover, age of the bear, activity and the interaction between age and activity. No significant relationships were found for flight distance nor duration. My findings support the hypothesis that brown bears are wary of people and does not alter their flight responses when repeatedly disturbed by humans on foot. SAMMENDRAG Kunnskap om møter mellom mennesker og vilt er viktig for forvaltning, vern og utforming av retningslinjer, samtidig som økt kunnskap kan redusere konflikt og negative interaksjoner. Flere har utrykt bekymring for at et økende antall møter mellom mennesker og vilt kan redusere viltets fluktresponser. Jeg har eksperimentelt undersøkt hvordan GPS-utstyrte brunbjørner (Ursus arctos) i sentrale deler av Sverige responderer når de gjentatte ganger møter mennesker til fots. Brunbjørner er generelt sky og unngår konfrontasjoner, og min hypotese var derfor at deres adferds ikke ville endre seg med antallet eksperimentelle møter. Observatører nærmet seg bjørnene til fots 2 – 3 ganger per uke over en periode på 2 – 4 uker. De simulerte turgåere, og passerte bjørnens intielle posisjon med en gjennomsnittsavstand på 29 meter. Totalt 11 binner (7 unge og 4 voksne) og 14 hannbjørner (6 unge og 8 voksne) ble utsatt for i gjennomsnitt 6.6 eksperimentelle møter (SD =1.19). Jeg analyserte fluktrespons som avstanden mellom bjørn og observatør idet bjørnen flyktet (FID), avstand bjørnen flyktet og hvor lenge den forble aktiv etter forstyrrelsen. Sammen med målinger av horisontal dekning ble data analysert ved hjelp av generalle linære modeller med bjørneindivid som tilfeldig effekt. Jeg fant ikke noen signifikant sammenheng mellom antallet approacher utført på et individ og dens fluktrespons. FID kunne best forklares med horisontal dekning, bjørnens alder, bjørnens aktivitet og interaksjonen mellom alder og aktivitet. Ingen signifikant sammenheng ble funnet med fluktdistanse eller varighet. Mine funn støtter hypotesen om at brunbjørn skyr mennesker og utviser fluktrespons selv når forstyrret gjentatte ganger.M-ECO

Cerebrospinal fluid markers in Creutzfeldt-Jakob disease

<p>Abstract</p> <p>Background</p> <p>The objective was to assess the utility of total tau protein (tTau), the ratio of (tTau)/181 phosphorylated tau protein (P-Tau) and 14-3-3 protein, as diagnostic markers in cerebrospinal fluid (CSF) for Creutzfeldt-Jakob disease (CJD).</p> <p>Methods</p> <p>CSF samples received from Norwegian hospitals between August 2005 and August 2007 were retrospectively selected from consecutive patients with tTau values > 1200 ng/L (n = 38). The samples from patients clinically diagnosed with CJD (n = 12) were compared to those from patients with other degenerative neurological diseases: Alzheimer's/vascular dementia (AD/VaD, n = 21), other neurological diseases (OND, n = 5). Total Tau, P-Tau, and β-Amyloid (Aβ₄₂) were measured with commercial kits. Additionally, 14-3-3 protein was measured semi-quantitatively by immunoblot.</p> <p>Results</p> <p>The minimum cut-off limits for diagnosis of CJD were chosen from the test results. For tTau the lower limit was fixed at 3000 ng/L, for the tTau/P-Tau ratio it was 60, and for 14-3-3 protein it was 0.75 arbitrary units. For tTau and tTau/P-Tau ratio, all but three CJD patients had levels above the minimum, whereas almost all of the other patients were below. For the 14-3-3 protein, two CJD patients were below the minimum and five were above. Only one of the other patients was higher than the limit. The sensitivities, specificities and diagnostic efficiencies were: tTau 75%, 92%, and 87%; tTau/P-Tau 75%, 96%, and 89%; and 14-3-3 protein 80%, 96%, and 91%.</p> <p>Conclusion</p> <p>The results suggest that 14-3-3 protein may be the better marker for CJD, tTau/P-Tau ratio and tTau are also efficient markers, but showed slightly inferior diagnostic properties in this study, with tTau/P-Tau marginally better than tTau.</p

Cerebral white matter changes : Differentiating vascular and degenerative cognitive impairment

Different types of dementia are difficult to identify in vivo, especially at early stages and partly due to the frequent co-existence of various etiologies. Recent techniques, including examination of biomarkers in cerebrospinal fluid (CSF) and advanced brain imaging techniques facilitate a more precise diagnosis of a given type of dementia. As previous diagnostic criteria for the Alzheimer type of dementia (AD) only captured the disease after dementia occured, new criteria involving recent biomarkers aim to arrive at a diagnosis at early stages, even prior to the onset of overt dementia. Along with episodic memory impairment, neuroimaging and CSF analysis have been proposed as reliable and important tools to make an accurate AD diagnosis possible, including forms of AD with co-existing cerebrovascular disease. The objective of this thesis aims to exploit the posssibilities of CSF analysis and neuroimaging in order to better understand the relationship between cerebrovascular and degenerative changes and cognition. To do so, measures of cerebral white matter changes from magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) were studied in cognitively impaired patients and compared to levels of CSF biomarkers and cognition. In degenerative and vascular cognitive impairment, risk factors and pathological disease processes have been well mapped. However, it remains unclear which exact mechanisms trigger these processes and in which way white matter changes and cortical events are connected. Improved early diagnostic specificity and better knowledge of interaction between vascular and degenerative changes may give rise to specific approaches to prevention and therapy, based upon individual risk-profiles

Impact of White Matter Lesions on Cognition in Stroke Patients Free from Pre-Stroke Cognitive Impairment: A One-Year Follow-Up Study

Background/Aim: Post-stroke cognitive impairment and dementia may be caused by pure vascular, pure degenerative or mixed disease. The relation between post-stroke cognitive impairment and the combination of vascular pathology and degenerative changes is less evaluated. We aimed to evaluate the associations between white matter lesions (WMLs) and patient performance 1 year after stroke on tests of executive functioning, memory and visuospatial function, adjusted for the effects of lifestyle and disease-related factors, including medial temporal lobe atrophy (MTLA). Methods: Patients with a first-ever stroke or transient ischemic attack were invited to participate in the study. The associations between the cognitive test performances and WMLs were studied using linear regression [Trail Making Test B (TMT B) and 10-word test] and logistic regression (Clock Drawing Test). Results: In total, 199 patients completed the follow-up. The TMT B (p = 0.029) and the 10-word test (p = 0.014) were significantly associated with WMLs; however, the Clock Drawing Test (p = 0.19) was not. The TMT B (p = 0.018) and the 10-word test (p ≤ 0.001) were both significantly associated with MTLA. Conclusion: Impaired executive functioning and memory are significantly associated with WMLs and MTLA. The mechanisms explaining post-stroke cognitive impairment are multifactorial, including different types of vascular pathology and coexisting vascular and degenerative changes

Disrupted Small-World Brain Networks in Moderate Alzheimer's Disease: A Resting-State fMRI Study

The small-world organization has been hypothesized to reflect a balance between local processing and global integration in the human brain. Previous multimodal imaging studies have consistently demonstrated that the topological architecture of the brain network is disrupted in Alzheimer's disease (AD). However, these studies have reported inconsistent results regarding the topological properties of brain alterations in AD. One potential explanation for these inconsistent results lies with the diverse homogeneity and distinct progressive stages of the AD involved in these studies, which are thought to be critical factors that might affect the results. We investigated the topological properties of brain functional networks derived from resting functional magnetic resonance imaging (fMRI) of carefully selected moderate AD patients and normal controls (NCs). Our results showed that the topological properties were found to be disrupted in AD patients, which showing increased local efficiency but decreased global efficiency. We found that the altered brain regions are mainly located in the default mode network, the temporal lobe and certain subcortical regions that are closely associated with the neuropathological changes in AD. Of note, our exploratory study revealed that the ApoE genotype modulates brain network properties, especially in AD patients

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat