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Cardiovascular diseases have been the leading cause of global mortality and disability. In addition to traditional drug and surgical treatment, more and more studies investigate tissue engineering therapeutic strategies in cardiovascular medicine. Collagen interweaves in the form of trimeric chains to form the physiological network framework of the extracellular matrix of cardiac and vascular cells, possessing excellent biological properties (such as low immunogenicity and good biocompatibility) and adjustable mechanical properties, which renders it a vital tissue engineering biomaterial for the treatment of cardiovascular diseases. In recent years, promising advances have been made in the application of collagen materials in blood vessel prostheses, injectable cardiac hydrogels, cardiac patches, and hemostatic materials, although their clinical translation still faces some obstacles. Thus, we reviewed these findings and systematically summarizes the application progress as well as problems of clinical translation of collagen biomaterials in the cardiovascular field. The present review contributes to a comprehensive understanding of the application of collagen biomaterials in cardiovascular medicine. [ABSTRACT FROM AUTHOR]

The family of room temperature atomic scale magnetometers is currently limited to nitrogen-vacancy centers in diamond. However, nitrogen-vacancy centers are insensitive to strong off-axis magnetic fields. In this work, we show that the well-known TR12 radiative defect in diamond, exhibits strong optically detected magnetic resonance (ODMR) signal under optical saturation. We also demonstrate that the spin system responsible for the magnetic resonance is an excited triplet state that can be coherently controlled at room temperature on a single defect level. The high optically detected magnetic resonance contrast, which is maintained even for strong off-axis magnetic fields, suggests that TR12 centers can be used for vector magnetometry even at high field. [ABSTRACT FROM AUTHOR]

Plasmonics is a promising technology that can find many applications in nanophotonics and biosensing. Local excitation of surface plasmons with high directionality is required for many of these applications. We demonstrate that by controlling the interference of light in a metal slot with the adjustment of the angle of incidence, it is possible to achieve highly directional surface plasmon excitation. Our numerical analysis of the structure showing a strong directionality of excited surface plasmon is confirmed by near field scanning measurements. The proposed structure can be useful for many applications including excitation of plasmonic waveguides, nanolithography, and optical sensing. To illustrate its usefulness, we experimentally demonstrate that it can be used for highly directional excitation of a dielectric loaded plasmonic waveguide. We also propose a simple structure for surface plasmon interference lithography capable of providing high image contrast using this scheme. [ABSTRACT FROM AUTHOR]

Background: Older adults spend most of their waking hours performing sedentary activities. The influence of these lifestyle patterns on the physical fitness (PF) levels of this population has not yet been sufficiently investigated. Objective: The aim of the study was to examine whether sedentary behavior (SB) (h•d-1sitting) is associated with PF, and specifically to analyze whether sitting >4 h•d-1 is associated with higher risk of having lower levels of fitness in seniors. Design: EXERNET multi-center study. Participants and Settings: A representative sample of 3136 non-institutionalized elderly (aged 72.2+5.3 years), from 6 Regions of Spain were included in the study. Measurements: PF was assessed using 8 different tests from the EXERNET battery. Lifestyle patterns were collected using a validated questionnaire. ANOVA was used to compare the groups according to the hours of sitting. Binary logistic regression was used to calculate the association between the SB and low levels of fitness. Results: For both genders, those who spent sitting >4 h•d-1 had lower levels of balance, agility, walking speed and aerobic endurance (p<0.001). Sedentary men also had less strength of lower extremities (p<0.05), whereas, sedentary women were less flexible in the lower extremities (p<0.001). More than 4 h•d-1 sitting was associated, in men, to higher odds for having low strength (lower extremities), agility, flexibility (lower extremities) and aerobic endurance (p<0.05); and in women, to higher risk of low balance, strength (lower and upper extremities), flexibility (lower extremities), agility, walking speed and aerobic endurance (p<0.05). Conclusions: Seniors that sit >4 h•d-1 have lower levels of fitness and this behavior is related with an increased risk of having low levels of PF in this population. [ABSTRACT FROM AUTHOR]

Physical activity promotes better health outcomes across the lifespan, and provides physical and mental health benefits for women who have recently given birth. However, research has not adequately characterized physical activity levels or risk factors for inadequate physical activity during the postpartum period. The objective of the present study was to describe levels and correlates of physical activity at 6 months postpartum in mothers of diverse race/ethnicity (55% African American, 23% White, 22% Hispanic/Latina), with the majority living in or near poverty. We analyzed data collected by the five-site Community Child Health Network study. Women (n = 1581) were recruited shortly after the birth of a child. Multinomial logistic regression models tested associations of demographic factors and self-reported stress in several life domains with total physical activity levels at 6-9 months postpartum, including activities done at work, at home, for transportation, and leisure. Thirty-five percent of participants in this sample reported low levels of physical activity. African American race, Latina ethnicity, and living in a rural area were associated with low levels of physical activity, whereas working outside the home was associated with high physical activity. Contrary to hypotheses, chronic stress was not associated with physical activity with the exception of financial stress, which predicted greater likelihood of being highly physically active. These findings suggest that optimal postpartum care should integrate physical activity promotion, and that African American, Latina, and rural-dwelling women may benefit most from efforts to promote activity following birth. [ABSTRACT FROM AUTHOR]

Carbon-fiber-reinforced plastics (CFRPs) are gaining increasing applicability to lightweight structures (e.g., automotive applications) due to their outstanding mechanical properties. High-performance parts can be fabricated from CFRPs, but they have the disadvantages of low shear and bearing strength. To achieve detachable connections and introduce loads without decreasing the load-bearing capacity of the composite, it is important to use mechanical fasteners without drilling into the parts. To accomplish this, metal elements called inserts are embedded in the CFRP laminate. Damage behavior in a CFRP under tensile conditions has several different mechanisms, depending primarily on the deformation of the insert. This research investigates the in-situ failure behavior of the composite under tensile loads by investigating the deformation of the insert via computed tomography (CT). The results are also used for validation of the insert's deformation using a finite-element model (FEM). [ABSTRACT FROM AUTHOR]

A recently proposed 'Projection-based Digital Volume Correlation' (P-DVC) method is extended in this work to a cone-beam lab-tomograph in which a mechanical test is performed. This consists of a crack propagation test in an elastic-brittle gypsum specimen. Kinematic analysis is performed based on a reduced finite element modeling for which the appropriate boundary conditions and crack propagation stage are determined from the radiographs. By considering only two projections per loading step, an integrated model-based analysis of the entire test provides a full space and time identification of the kinematics, including the crack position and the determination of two material parameters. This is achieved with a drastic reduction in the acquisition time compared to classical digital volume correlation analysis. In the examples presented, the acquisition time was reduced by a factor of 350. [ABSTRACT FROM AUTHOR]

Introduction: Cobalamin deficiency is frequent in elderly patients and the main aetiologies are foodcobalamin malabsorption and pernicious anaemia. The aim of our retrospective study was to identify the causes and methods of management of cobalamin deficiency at Nice geriatric university hospital. Methods: A retrospective monocentric study was conducted over 14 months at Nice geriatric hospital, which included patients with cobalamin deficiency having received supplementation. The clinical and paraclinical data, etiological diagnosis, treatment and follow-up modalities were analyzed retrospectively. Results: We studied 125 elderly patients whose median age was 85.5 ± 7 years. The etiological diagnosis was food-cobalamin malabsorption for 72 patients (57.6 %), nutritional cobalamin deficiency for 15 patients (12 %), pernicious anaemia for 12 patients (9.6 %) and there was no etiological diagnosis for 26 patients (20.8 %). Concerning cobalamin therapy, 111 patients (88.8 %) received oral therapy and 14 (11.2 %) intramuscular therapy. Vitamin B12 levels increased significantly after supplementation (p<0.001) but cobalamin administration varied according to the diagnoses (p<0.001) and was less effective in patients with dementia (p=0.04) and food-cobalamin malabsorption. Conclusion: Our study showed the importance of food-cobalamin malabsorption in etiological diagnosis in accordance with the literature, but also the non-negligible share of nutritional cobalamin deficiency. Mainly oral cobalamin supplementation was used in our study with a significant increase in vitamin B12 levels. An oral cobalamin regimen is proposed for elderly patients with cobalamin deficiency but with no severe neurological signs. [ABSTRACT FROM AUTHOR]

Autism spectrum disorders (ASD) are defined by behavioral deficits in social interaction and communication, repetitive stereotyped behaviors, and restricted interests/cognitive rigidity. Recent studies in humans and animal-models suggest that dysfunction of the cholinergic system may underlie autism-related behavioral symptoms. Here we tested the hypothesis that augmentation of acetylcholine (ACh) in the synaptic cleft by inhibiting acetylcholinesterase may ameliorate autistic phenotypes. We first administered the acetylcholinesterase inhibitor (AChEI) Donepezil systemically by intraperitoneal (i.p.) injections. Second, the drug was injected directly into the rodent homolog of the caudate nucleus, the dorsomedial striatum (DMS), of the inbred mouse strain BTBR T+tf/J (BTBR), a commonly-used model presenting all core autism-related phenotypes and expressing low brain ACh levels. We found that i.p. injection of AChEI to BTBR mice significantly relieved autism-relevant phenotypes, including decreasing cognitive rigidity, improving social preference, and enhancing social interaction, in a dose-dependent manner. Microinjection of the drug directly into the DMS, but not into the ventromedial striatum, led to significant amelioration of the cognitive-rigidity and social-deficiency phenotypes. Taken together, these findings provide evidence of the key role of the cholinergic system and the DMS in the etiology of ASD, and suggest that elevated cognitive flexibility may result in enhanced social attention. The potential therapeutic effect of AChEIs in ASD patients is discussed. [ABSTRACT FROM AUTHOR]

Objectives: To identify factors associated with survival to the age of 90 years old in 70+ elderly people. Design: The PAQUID prospective cohort on brain and functional ageing. Setting: 75 randomly selected administrative communities in Gironde and Dordogne (France). Participants: A sub-sample of 2,578 community dwellers aged 70 years and over at baseline in 1988 and followed-up over 20 years, all participants of the PAQUID study. Measurements: Data on socio-material environments, lifestyle, health, perceived health, and family background were collected at home every 2–3 years over 20 years, with a prospective update of vital status. Participants were compared according to their survival status (subjects who reached 90 compared to those who did not). The factors associated with survival were investigated separately for men and women by Cox regression with, as much as possible, time-dependent variables. Results: Some factors associated with survival were common to both genders, whereas some others appeared gender specific. For men, tenant status (HR=1.46), former or current smoking (HR=1.17), disability (respective HR of 1.50, 1.78 and 2.81 for mild, moderate and severe level), dementia (HR=1.51), a recent hospitalisation (HR=1.32), dyspnoea (HR=1.32), and cardiovascular symptoms (HR=1.15) were associated with lower chance of becoming nonagenarian. Conversely, regular physical activity (HR=0.74) was associated with higher chance of survival. For women, the presence of a professional help (HR=1.19), living arrangements (HR=1.29 and HR=1.33), disability (respective HR of 1.55, 1.95 and 2.70 for mild, moderate and severe disability), dementia (HR=1.54), a recent hospitalisation (HR=1.19), diabetes (HR=1.49), and dyspnoea (HR=1.20) were associated with lower chance of becoming nonagenarian. Conversely, satisfaction of level income (HR=0.87), comfortable housing (HR=0.81), length of living in the dwelling (HR=0.80 upper to 6 years), regular physical activity (HR=0.89) and a medium (HR=0.79) or good (HR=0.68) subjective health, were associated with higher chance of becoming nonagenarian. Conclusion: Our findings confirm that survival up to 90 is a multifactorial phenomenon with similarities and specificities by gender. Consequently, primary prevention and global consideration of ageing (social, material, financial, psychological) are necessary to promote not only longevity but also successful ageing in order to face the future societal challenges due to demographic ageing. [ABSTRACT FROM AUTHOR]

Engagement in walking for recreation can contribute to healthy aging. Although there is growing evidence that the neighborhood environment can influence walking for recreation, the amount of such evidence in relation to older adults is scarce and limited to Western low-density urban locations. Asian urban environments are typified by distinctive environmental and cultural characteristics that may yield different patterns to those observed in Western countries. Therefore, the main aim of this study was to examine associations of perceived environmental attributes with overall and within-neighborhood walking for recreation in Chinese elders (65+ years) residing in Hong Kong, an ultradense Asian metropolis. A sample of 484 elders was recruited from 32 neighborhoods stratified by socio-economic status and walkability (dwelling and intersection densities). Validated questionnaires measuring perceived neighborhood environment and weekly minutes of overall and within-neighborhood walking for recreation were interviewer administered. Results showed that the level of recreational walking was twice to four times higher than that reported in Western adults and elders. While overall walking for recreation showed a general lack of associations with perceived environmental attributes, within-neighborhood recreational walking was positively related with proximity of recreational facilities, infrastructure for walking, indoor places for walking, and presence of bridge/overpasses connecting to services. Age and educational attainment moderated the associations with several perceived environmental attributes with older and less-educated participants showing stronger associations. Traditional cultural views on the benefits of physical activity and the high accessibility of facilities and pedestrian infrastructure of Hong Kong may explain the high levels of walking. Although specific neighborhood attributes, or their perception, may influence recreational walking within the neighborhood, the compactness and public transport affordability of ultradense metropolises such as Hong Kong may make it easy for elders to compensate for the lack of favorable neighborhood attributes by walking outside the neighborhood. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to evaluate the efficiency of a short-term Intermittent Work Exercise Program (IWEP) among healthy elderly subjects. Study design and setting: This longitudinal prospective study took place at the Strasbourg University Hospital geriatric department. Study participants: One hundred and fifty older volunteers, previously determined as being free from cardiac and pulmonary disease, were separated into two age groups: the 'young senior' (60.2 ± 3.1 yr) and the 'older senior' groups (70.8 ± 5.2 yr).These groups were then subdivided by gender into the 'young female senior', 'young male senior' 'older female senior' and 'older male senior' groups. Intervention: Before and after the IWEP, all subjects were asked to perform an incremental cycle exercise to obtain their first ventilatory threshold (VT), maximal tolerated power (MTP), peak oxygen uptake (VO) and maximal minute ventilation (MMV). The IWEP consisted of a 30-min cycling exercise which took place twice a week, and was divided into six 5-min stages consisting of 4 min at VT intensity and 1 min at 90% MTP. Measurements: An assessment was made of the effects of the IWEP on maximal cardio-respiratory function (MTP, VO, MMV) and endurance parameters (VT, heart rate [HR] measured at pretraining VT and lactate concentrations at pre-training MTP). Results: This short-term training program resulted in a significant increase of MTP (from 13.2% to 20.6%), VO (from 8.9% to 16.6%) and MMV (from 11.1% to 21.8%) in all groups (p<0.05). VT1 improved from 21% at pretraining to 27%, while HR at pre-training VT1 as well as lactate concentrations at pre-training MTP decreased significantly in all groups (p<0.05). The post-training values for VO and MMV of the 'older seniors' were not significantly different (p>0.05) from the 'young seniors' pre-training values for the same parameters. Conclusion: The most striking finding in this study is that after only 9 weeks, our short-term 'individually-tailored' IWEP significantly improved both maximal cardio-respiratory function and endurance parameters in healthy, previously untrained seniors. [ABSTRACT FROM AUTHOR]

The European Dementia Consensus Network (EDCON) is a special project of the Madariaga Foundation located in Brussels. The Madariaga Foundation seeks to facilitate collaboration between European countries and between the public and private sector. This paper will review the differences in the definitions of Severe Dementia and summarise the EDCON consensus on their implications for management. EDCON recommends that: - The attributes of the person suffering from dementia should be given as much attention (and are as important for care) as the severity of cognitive decline in dementia; - The dementia syndrome (particularly in it's severe form) is inadequately defined by criteria which only includes the domain of cognition; - Physical, legal, social and cultural factors defining the environment of patients and their families should be carefully examined and that the results of this examination should be used in conjunction with the results of the somatic and psychiatric assessment in planning care and placement of the patient; - patients with severe dementia should have access to palliative care; - family members should be included in the care plans for those with severe dementia who are in institutional care. [ABSTRACT FROM AUTHOR]

Colony sizes in birds can vary by orders of magnitude within species, and many studies have shown that selection pressures differ dramatically among small and large colonies. Does such selection result in phenotypic sorting at the level of individuals? This study describes inter-colony differences in morphology and reproductive investment in a population of a highly colonial, communal and sedentary African passerine bird, the sociable weaver Philetairus socius. Relative colony sizes were fairly stable over a 10-year period. Adults differed among colonies in terms of bill morphology, condition, body size and degree of ectoparasite infestation, and the last two declined consistently with colony size. In larger colonies, smaller eggs were laid, and nestlings were more parasite-infested, showed weaker cell-mediated immune responses, and experienced higher levels of brood reduction and snake predation. Taken together with another study showing that adult survival is higher in larger colonies, these results suggest that patterns of age-specific mortality are consistently related to colony size in the sociable weaver. Based on these observations I suggest two hypotheses that might account for the observed phenotypic sorting, involving colony size-dependent patterns in (1) density-dependent competition for food and (2) adaptive life-history adjustment. [ABSTRACT FROM AUTHOR]

Situations involving competition for resources among entities can be modeled by the competitive multi-armed bandit (CMAB) problem, which relates to social issues such as maximizing the total outcome and achieving the fairest resource repartition among individuals. In these respects, the intrinsic randomness and global properties of quantum states provide ideal tools for obtaining optimal solutions to this problem. Based on the previous study of the CMAB problem in the two-arm, two-player case, this paper presents the theoretical principles necessary to find polarization-entangled N-photon states that can optimize the total resource output while ensuring equality among players. These principles were applied to two-, three-, four-, and five-player cases by using numerical simulations to reproduce realistic configurations and find the best strategies to overcome potential misalignment between the polarization measurement systems of the players. Although a general formula for the N-player case is not presented here, general derivation rules and a verification algorithm are proposed. This report demonstrates the potential usability of quantum states in collective decision making with limited, probabilistic resources, which could serve as a first step toward quantum-based resource allocation systems. [ABSTRACT FROM AUTHOR]

Nitrogen-vacancy (NV) centres in diamond hold promise in quantum sensing applications. A major interest in them is an enhancement of their sensitivity by the extension of the coherence time (T2). In this report, we experimentally generated more than four dressed states in a single NV centre in diamond based on Autler-Townes splitting (ATS). We also observed the extension of the coherence time to T2 ~ 1.5 ms which is more than two orders of magnitude longer than that of the undressed states. As an example of a quantum application using these results we propose a protocol of quantum sensing, which shows more than an order of magnitude enhancement in the sensitivity. [ABSTRACT FROM AUTHOR]

We present an experimental illustration on the quantum sensitivity of decision making machinery. In the decision making process, we consider the role of available information, say hint, whether it influences the optimal choices. To the end, we consider a machinery method of decision making in a probabilistic way. Our main result shows that in decision making process our quantum machine is more highly sensitive than its classical counterpart to the hints we categorize into "good" and "poor". This quantum feature originates from the quantum superposition involved in the decision making process. We also show that the quantum sensitivity persists before the quantum superposition is completely destroyed. [ABSTRACT FROM AUTHOR]

Focused MeV ion beams with micrometric resolution are suitable tools for the direct writing of conductive graphitic channels buried in an insulating diamond bulk, as already demonstrated for different device applications. In this work we apply this fabrication method to the electrical excitation of color centers in diamond, demonstrating the potential of electrical stimulation in diamond-based single-photon sources. Differently from optically-stimulated light emission from color centers in diamond, electroluminescence (EL) requires a high current flowing in the diamond subgap states between the electrodes. With this purpose, buried graphitic electrode pairs, 10 μm spaced, were fabricated in the bulk of a single-crystal diamond sample using a 6 MeV C microbeam. The electrical characterization of the structure showed a significant current injection above an effective voltage threshold of 150 V, which enabled the stimulation of a stable EL emission. The EL imaging allowed to identify the electroluminescent regions and the residual vacancy distribution associated with the fabrication technique. Measurements evidenced isolated electroluminescent spots where non-classical light emission in the 560-700 nm spectral range was observed. The spectral and auto-correlation features of the EL emission were investigated to qualify the non-classical properties of the color centers. [ABSTRACT FROM AUTHOR]