followers of honey bee tremble and waggle dances exhibit similar behaviors

The function of the honey bee tremble dance and how it attracts signal receivers is poorly understood. We tested the hypothesis that tremble followers and waggle followers exhibit the same dance-following behavior. If correct, this could unify our understanding of dance following, provide insight into dance information transfer, and offer a way to identify the signal receivers of tremble dance information. Followers showed similar initial attraction to and tracking of dancers. However, waggle dancers were faster than tremble dancers, and follower-forward, -sideways, and -angular velocities were generally similar to the velocities of their respective dancers. Waggle dancers attracted followers from 1.3-fold greater distances away than tremble dancers. Both follower types were attracted to the lateral sides of dancers, but tremble followers were more attracted to the dancer's head, and waggle followers were more attracted to the dancer's abdomen. Tremble dancers engaged in 4-fold more brief food exchanges with their followers than waggle dancers. The behaviors of both follower types are therefore relatively conserved. Researchers can now take the next steps, observing tremble followers to determine their subsequent behaviors and testing the broader question of whether follower attraction and tracking is conserved in a wide range of social insects

Modeling dynamic controls on ice streams: a Bayesian statistical approach

Our main goal is to exemplify the study of ice-stream dynamics via Bayesian statistical analysis incorporating physical, though imperfectly known, models using data that are both incomplete and noisy. The physical-statistical models we propose account for these uncertainties in a coherent, hierarchical manner. The initial modeling assumption estimates basal shear stress as equal to driving stress, but subsequently includes a random corrector process to account for model error. The resulting stochastic equation is incorporated into a simple model for surface velocities. Use of Bayes\u27 theorem allows us to make inferences on all unknowns given basal elevation, surface elevation and surface velocity. The result is a posterior distribution of possible values that can be summarized in a number of ways. For example, the posterior mean of the stress field indicates average behavior at any location in the field, and the posterior standard deviations describe associated uncertainties. We analyze data from the \u27Northeast Greenland Ice Stream\u27 and illustrate bow scientific conclusions may be drawn from our Bayesian analysis

Relationship between cortical thickness and neuropsychological performance in normal older adults and those with mild cognitive impairment

Mild cognitive impairment (MCI) has been extensively investigated in recent decades to identify groups with a high risk of dementia and to establish effective prevention methods during this period. Neuropsychological performance and cortical thickness are two important biomarkers used to predict progression from MCI to dementia. This study compares the cortical thickness and neuropsychological performance in people with MCI and cognitively healthy older adults. We further focus on the relationship between cortical thickness and neuropsychological performance in these two groups. Forty-nine participants with MCI and 40 cognitively healthy older adults were recruited. Cortical thickness was analysed with semiautomatic software, Freesurfer. The analysis reveals that the cortical thickness in the left caudal anterior cingulate (p=0.041), lateral occipital (p=0.009) and right superior temporal (p=0.047) areas were significantly thinner in the MCI group after adjustment for age and education. Almost all neuropsychological test results (with the exception of forward digit span) were significantly correlated to cortical thickness in the MCI group after adjustment for age, gender and education. In contrast, only the score on the Category Verbal Fluency Test and the forward digit span were found to have significant inverse correlations to cortical thickness in the control group of cognitively healthy older adults. The study results suggest that cortical thinning in the temporal region reflects the global change in cognition in subjects with MCI and may be useful to predict progression of MCI to Alzheimer's disease. The different pattern in the correlation of cortical thickness to the neuropsychological performance of patients with MCI from the healthy control subjects may be explained by the hypothesis of MCI as a disconnection syndrome

Traumatic Brain Injury in the Elderly: Is it as Bad as we Think?

Traumatic brain injury in elderly patients is a neglected global disease burden. The main cause is fall, followed by motor vehicle accidents. This review article summarizes different aspects of geriatric traumatic brain injury, including epidemiology, pathology, and effects of comorbidities and pre-injury medications such as antiplatelets and anticoagulants. Functional outcome with or without surgical intervention, cognitive outcome, and psychiatric complications are discussed. Animal models are also reviewed in attempt to explain the relationship of aging and outcome, together with advances in stem cell research. Though elderly people in general did fare worse after traumatic brain injury, certain “younger elderly” people, aged 65–75 years, could have a comparable outcome to younger adults after minor to moderate head injury

Would transcranial direct current stimulation (tDCS) enhance the effects of working memory training in older adults with mild neurocognitive disorder due to Alzheimer’s disease: study protocol for a randomized controlled trial

© 2015 Cheng et al. Background: There has been longstanding interesting in cognitive training for older adults with cognitive impairment. In this study, we will investigate the effects of working memory training, and explore augmentation strategies that could possibly consolidate the effects in older adults with mild neurocognitive disorder. Transcranial direct current stimulation (tDCS) has been demonstrated to affect the neuronal excitability and reported to enhance memory performance. As tDCS may also modulate cognitive function through changes in neuroplastic response, it would be adopted as an augmentation strategy for working memory training in the present study. Methods/Design: This is a 4-week intervention double-blind randomized controlled trial (RCT) of tDCS. Chinese older adults (aged 60 to 90 years) with mild neurocognitive disorder due to Alzheimer 's disease (DSM-5 criteria) would be randomized into a 4-week intervention of either tDCS-working memory (DCS-WM), tDCS-control cognitive training (DCS-CC), and sham tDCS-working memory (WM-CD) groups. The primary outcome would be working memory test - the n-back task performance and the Chinese version of the Alzheimer's Disease Assessment Scale - Cognitive Subscale (ADAS-Cog). Secondary outcomes would be test performance of specific cognitive domains and mood. Intention-to-treat analysis would be carried out. Changes of efficacy indicators with time and intervention would be tested with mixed effect models. Discussion: This study adopts the theory of neuroplasticity to evaluate the potential cognitive benefits of non-invasive electrical brain stimulation, working memory training and dual stimulation in older adults at risk of cognitive decline. It would also examine the tolerability, program adherence and adverse effects of this novel intervention. Information would be helpful for further research of dementia prevention studies. Trial registration: ChiCTR-TRC- 14005036Date of registration: 31 July 2014.published_or_final_versio

Impact of a moulded pureed diet on taste, appearance, recognisability, and overall liking among patients in an acute hospital

IntroductionHospital meals potentially influence patients’ nutritional, physical, and emotional well-being during their admission. Patients on pureed diets report poorer meal satisfaction, due to taste, appearance, and recognisability, potentially impacting on their nutritional status. This study compared whether a moulded pureed diet made from modified maize starch led to improved taste, appearance, recognisability, and overall liking, compared to an unmoulded pureed diet made from potato starch in an acute hospital.MethodsPatients on texture-modified diets were recruited and presented with two pureed diets – unmoulded and moulded. Participants were asked to identify meat and vegetable dishes prior to eating. After the meal, participants indicated their diet preference in terms of appearance, taste, and overall liking.Results145 participants were recruited, of which 126 completed data collection. 86% correctly identified moulded meat dishes, 69% correctly identified moulded vegetable dishes, with an overall 77% accuracy in identifying moulded puree side dishes. On unmoulded puree side dishes, participants correctly identified 25% of meat dishes, 4% of vegetable dishes, with an overall accuracy of 14%. In terms of preference, the moulded puree was preferred, with 81% for appearance, 76% for taste and 75% for overall preference. When participants had differing preferences for appearance and taste (e.g., prefers unmoulded puree appearance and moulded puree taste), 95% of them subsequently aligned their overall preference with their taste preference (i.e., overall preferred moulded pureed diet). This suggests that taste has a stronger influence on overall preference compared to appearance.DiscussionFindings indicate that a moulded pureed diet made from modified maize starch led to improved recognisability, taste, appearance, and overall liking compared to an unmoulded pureed diet made from potato starch. Taste had a stronger influence on overall preference compared to appearance. These findings capture patient preferences and may have implications on how hospital pureed diets may be improved, potentially improving patient nutrition and health outcomes

Oral health of community dwelling elders in Hong Kong

Introduction: The world’s population is ageing and the elders are vulnerable to oral health problems. This project aimed to observe the oral health status of community dwelling elders in Hong Kong, investigate the oral health impact on their quality of life and nutritional status, and provide oral health education and preventive service. Methods: Community dwelling elders (65 or above) were recruited from five community centers. An interviewer-administered questionnaire was completed to collect information on their socio-demographic background and oral health perception/practice. Their oral health related quality of life (OHQoL) and nutritional status were measured by using the Geriatric Oral Health Assessment Index (GOHAI) and Mini-Nutritional Assessment (MNA), respectively. Their tooth and periodontal status, oral hygiene and soft tissues were examined. Individualized advice, oral health education and scaling were provided. Results: A total of 195 elders participated. Despite their sound knowledge on dental caries, their awareness of the causes and risk factors of periodontal diseases was low. Several misconceptions of oral health were common and their expectation towards oral health was low. Although 81% brush their teeth at least twice a day, over 75% did not perform interdental cleaning mainly due to unawareness of the necessity (32%) and lack of skills (42%). Their dental visits were treatment-driven and mainly for pain-relieving and emergency care. Only 19% were regular dental attendees. The mean (SD) DMFT was 8.9 (7.8). Over 60% had periodontal pockets; 6% were edentulous and 38% had fewer than 20 teeth. The mean (SD) total GOHAI score was 56.4 (8.0); 60% reported negative impact of oral health on their quality of life. The mean (SD) MNA score was 25.2 (2.9); 30% had malnutrition or were at risk. Multivariate analysis showed that tooth loss and untreated decayed teeth (DT) were significant determinants of poor OHQoL; older age, higher education level, and poorer OHQoL were significantly associated with higher risk of malnutrition (all p<0.05). Conclusions: Oral health problems are common among community dwelling elders in Hong Kong. Their oral health awareness and practice are yet to be improved. Tooth loss and unmet treatment need for dental caries significantly compromise elders’ quality of life, which in turn increases their risk for malnutrition. Outreach oral health education and service are well received by the community.published_or_final_versio

Medial open transversus abdominis plane (MOTAP) catheters for analgesia following open liver resection: study protocol for a randomized controlled trial

Background: The current standard for pain control following liver surgery is intravenous, patient-controlled analgesia (IV PCA) or epidural analgesia. We have developed a modification of a regional technique called medial open transversus abdominis plane (MOTAP) catheter analgesia. The MOTAP technique involves surgically placed catheters through the open surgical site into a plane between the internal oblique muscle and the transverse abdominis muscle superiorly. The objective of this trial is to assess the efficacy of this technique. Methods/design: This protocol describes a multicentre, prospective, blinded, randomized controlled trial. One hundred and twenty patients scheduled for open liver resection through a subcostal incision will be enrolled. All patients will have two MOTAP catheters placed at the conclusion of surgery. Patients will be randomized to one of two parallel groups: experimental (local anaesthetic through MOTAP catheters) or placebo (normal saline through MOTAP catheters). Both groups will also receive IV PCA. The primary endpoint is mean cumulative postoperative opioid consumption over the first 2 postoperative days (48 hours). Secondary outcomes include pain intensity, patient functional outcomes, and the incidence of complications. Discussion: This trial has been approved by the ethics boards at participating centres and is currently enrolling patients. Data collection will be completed by the end of 2014 with analysis mid-2015 and publication by the end of 2015. Trial registration: The study is registered with http://clinicaltrials.gov (NCT01960049; 23 September 2013)This research is supported by the Innovation Fund of the Alternative Funding Plan from the Academic Health Sciences Centres of Ontario