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The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
This pilot study was designed to assess the feasibility of implementing a mindfulness intervention in the prevention of falls. We employed a quasi-experimental design consisting of 22 participants from two retirement homes in Ontario partaking in the regional falls prevention class. Participants were assigned to either an eight-week intervention, comprising mindfulness exercises incorporated into the standard falls prevention class, or to the standard falls prevention class. Participants were assessed using the Tinetti Balance and Gait Scale and the Timed Up and Go (TUG) test. The mindfulness intervention showed no significant effect on TUG or balance scores; however, there was a significant effect on assessments of gait. Given the ease of implementation of mindfulness-based interventions, further research may be warranted in mindfulness as a potential modality for falls prevention.
‘Ground effect’ refers to the enhanced performance enjoyed by fliers or swimmers operating close to the ground. We derive a number of exact solutions for this phenomenon, thereby elucidating the underlying physical mechanisms involved in ground effect. Unlike previous analytic studies, our solutions are not restricted to particular parameter regimes, such as ‘weak’ or ‘extreme’ ground effect, and do not even require thin aerofoil theory. Moreover, the solutions are valid for a hitherto intractable range of flow phenomena, including point vortices, uniform and straining flows, unsteady motions of the wing, and the Kutta condition. We model the ground effect as the potential flow past a wing inclined above a flat wall. The solution of the model requires two steps: firstly, a coordinate transformation between the physical domain and a concentric annulus; and secondly, the solution of the potential flow problem inside the annulus. We show that both steps can be solved by introducing a new special function which is straightforward to compute. Moreover, the ensuing solutions are simple to express and offer new insight into the mathematical structure of ground effect. In order to identify the missing physics in our potential flow model, we compare our solutions against new experimental data. The experiments show that boundary layer separation on the wing and wall occurs at small angles of attack, and we suggest ways in which our model could be extended to account for these effects.
We aimed to profile vegetable consumption and its association with dietary and sociodemographic factors.
Secondary analysis of a nationally representative nutrition survey. ‘Vegetables’ refers to non-discretionary ‘vegetables and legumes/beans’ as defined by the Australian Dietary Guidelines (ADG). Prevalence of vegetable consumption, frequency of intake, proportion meeting ADG recommendations, most popular food groups, intake at each reported eating occasion, and the profile of high and low vegetable consumers (based on the median servings) were determined.
Australian 2011–2012 National Nutrition and Physical Activity Survey.
Children and adolescents aged 2 to 18 years (n 2812).
Vegetables were consumed by 83·0% (95% CI 81·6, 84·4%) of participants, but the median vegetable servings was less than a third of the ADG recommendations. ‘Leaf and stalk vegetables’ and ‘potatoes’ were the most popular vegetable-dense food groups at lunch and dinner, respectively. Sixty-four percent had vegetables once a day, and predominantly at dinner. Vegetable frequency was positively associated with daily vegetable servings and variety. Participants who consumed vegetables twice a day generally had vegetables at both lunch and dinner and had nearly double the servings (2·6, sd 1·9) of those who consumed them once (1·5, sd 1·5). High vegetable consumers were older, had higher total energy, but lower discretionary energy intake and were less likely to be at risk of metabolic complications.
Increasing the frequency of vegetable consumption may assist with increasing daily vegetable servings. A focus on consuming vegetables at lunch may assist with increasing both total servings and variety.
OBJECTIVES/SPECIFIC AIMS: The National HIV/AIDS strategy aims to increase retention in care (RIC) to reduce HIV transmission and mortality. Previous studies have evaluated clinic-level interventions such as appointment reminders and peer navigation. However, few studies have investigated the association between multiple clinic-level factors and RIC among PLWH across the United States. We conducted a multi-site cohort study to identify clinic-level factors associated with RIC in the United States from 2010-2016. METHODS/STUDY POPULATION: We included PLWH with at least one HIV primary care visit from 2010-2016 at seven sites of the Center for AIDS Research (CFAR) Network of Integrated Clinical Systems (CNICS). Individual-level data collected as part of routine clinical care were abstracted from the electronic health record. Clinic-level data were gathered through a survey and included questions on site characteristics (i.e. clinic volume) as well as services available at the site during each year of the study: peer navigation, RIC posters/brochures, laboratory test timing, flexible scheduling, appointment reminder types, and stigma support services defined as intensive HIV education and advocacy regarding support to address stigma at outreach visits. RIC was defined as ≥2 encounters per year, ≥90 days apart, observed until death, administrative censoring (December 31, 2016), or loss to follow-up (no visit for >12 months with no future visits). Poisson panel regression with robust error variance, clustering by site and adjusting for calendar year, age (modeled with a cubic spline), sex, race/ethnicity, and HIV transmission risk factor, was used to estimate incident rate ratios (IRR) with 95% confidence intervals (CI) for RIC. Clustering by site has been shown to absorb for clustering that could occur at the individual level as well. RESULTS/ANTICIPATED RESULTS: Among 21,046 patients contributing 103,348 person-years, 67% of person-years were RIC. Text appointment reminders (IRR = 1.13; 95% CI: 1.03-1.24) and stigma support services (IRR=1.11; 95% CI:1.04-1.19) were significantly associated with RIC. RIC disparities in individual-level patient characteristics were observed even after accounting for clinic-level characteristics. Older patients were more likely to be RIC demonstrated through year comparisons due to the use of a spline; for age 50 years (IRR = 1.07, 95% CI: 1.06-1.08) and 60 years (IRR = 1.15, 95% CI: 1.13-1.17) compared to 45 years. Female PLWH were more likely to be RIC compared to males (IRR = 1.03, 95% CI: 1.02-1.05) and Hispanic PLWH were more likely to be RIC compared to white, non-Hispanic PLWH (IRR = 1.09, 95% CI: 1.05-1.13). Although commonly found to be associated with worse RIC, Black race and injection drug use were not associated with RIC in this population. DISCUSSION/SIGNIFICANCE OF IMPACT: In this multi-site US cohort study from 2010-2016, availability of text appointment reminders and stigma support services at a clinic were associated with approximately 10% higher probability of RIC than at clinics without those services. RIC disparities persisted with respect to individual-level characteristics of age, sex, and race/ethnicity even after accounting for these clinic-level factors. Prospective studies examining the impact of these clinic-level factors and individual-level uptake of these services on RIC are needed.
To profile discretionary food and beverage (DF) consumption among Australian adults.
Cross-sectional analysis. Dietary and sociodemographic data were used to profile DF intake. Prevalence of DF consumption, DF servings (1 serving=600 kJ), nutrient contribution from DF and top DF food groups by self-reported eating occasions were determined. DF consumers (>0 g) were classified according to quartile of DF intake and general linear models adjusted for age and sex were used to determine associations.
2011–12 National Nutrition and Physical Activity Survey (NNPAS).
Adults aged ≥19 years (n 9341) who participated in the NNPAS 2011–12.
Most adults consumed DF (98 %) and over 60 % exceeded 3 DF servings/d, with a mean of 5·0 (se 0·0) DF servings/d. Cakes, muffins, scones, cake-type desserts contributed the most DF energy (8·4 %) of all food groups, followed by wines (8·1 %), pastries (8·0 %) and beers (6·1 %), with all these food groups consumed in large portions (2·3–3·0 DF servings). Lunch and dinner together contributed 45 % of total DF energy intake. High DF consumers had an average of 10 DF servings, and this group contained more younger adults, males, low socio-economic status, lower usual fruit intake and higher mean waist circumference, but not higher BMI.
A focus on DF consumed in large portions at lunch and dinner may help improve interventions aimed at reducing DF intake and addressing negative adiposity-related measures found in high DF consumers.
Tumor necrosis factor alpha-induced protein 3 (TNFAIP3) is a multifunctional ubiquitin binding and editing enzyme that regulates inflammation. Genetic studies have implicated polymorphisms within the TNFAIP3 locus to the development of numerous immune-related diseases. This study evaluated the frequencies of single-nucleotide polymorphism (SNPs) within the exonic regions of the TNFAIP3 gene and an associated point mutation from the Illumina array among a predominantly Hispanic cohort.
Genomic DNA was obtained from 721 participants and sequencing of all TNFAIP3 exons and an intergenic point mutation (rs6920220) was performed. In-vitro functional assessment was performed by transfecting mutated TNFAIP3 constructs into TNFAIP3 knockout cells containing the NF-kB luciferase reporter and stimulating with TNFα. Comparative statistics were performed with Student’s t-test for continuous variables and chi-squared test for categorical variables.
Sequencing revealed two missense SNPs, rs146534657:A>G and rs2230926:T>G, both within exon 3 of TNFAIP3, which encodes the protein’s deubiquitinating enzymatic domain. Frequencies of all three point mutations differed significantly across racial groups (χ2-test, P = 0.014 to P < 0.001). Compared to Caucasians, rs146534657:A>G was overrepresented among Hispanics (odds ratio (OR) [95% CI] 4.05 [1.24−13.18]), and rs2230926:T>G was more prevalent among African-Americans (OR [95% CI] 3.65 [1.58−8.43]). In-vitro assays confirm rs146534657:A>G and rs2230926:T>G decrease the ability of TNFAIP3 to abrogate NF-κB activation by 2-fold (P < 0.01) and 1.7-fold (P < 0.01), respectively.
This study reports the frequency of rs146534657:A>G among Hispanics and is the first to evaluate its potential physiologic impact, establishing a basis for future research as a potential biomarker among this population.
Although school-based programmes for the identification of children and young people (CYP) with mental health difficulties (MHD) have the potential to improve short- and long-term outcomes across a range of mental disorders, the evidence-base on the effectiveness of these programmes is underdeveloped. In this systematic review, we sought to identify and synthesise evidence on the effectiveness and cost-effectiveness of school-based methods to identify students experiencing MHD, as measured by accurate identification, referral rates, and service uptake.
Electronic bibliographic databases: MEDLINE, Embase, PsycINFO, ERIC, British Education Index and ASSIA were searched. Comparative studies were included if they assessed the effectiveness or cost-effectiveness of strategies to identify students in formal education aged 3–18 years with MHD, presenting symptoms of mental ill health, or exposed to psychosocial risks that increase the likelihood of developing a MHD.
We identified 27 studies describing 44 unique identification programmes. Only one study was a randomised controlled trial. Most studies evaluated the utility of universal screening programmes; where comparison of identification rates was made, the comparator test varied across studies. The heterogeneity of studies, the absence of randomised studies and poor outcome reporting make for a weak evidence-base that only generate tentative conclusions about the effectiveness of school-based identification programmes.
Well-designed pragmatic trials that include the evaluation of cost-effectiveness and detailed process evaluations are necessary to establish the accuracy of different identification models, as well as their effectiveness in connecting students to appropriate support in real-world settings.
As multi-core computing is now standard, it seems irresponsible for constraints researchers to ignore the implications of it. Researchers need to address a number of issues to exploit parallelism, such as: investigating which constraint algorithms are amenable to parallelisation; whether to use shared memory or distributed computation; whether to use static or dynamic decomposition; and how to best exploit portfolios and cooperating search. We review the literature, and see that we can sometimes do quite well, some of the time, on some instances, but we are far from a general solution. Yet there seems to be little overall guidance that can be given on how best to exploit multi-core computers to speed up constraint solving. We hope at least that this survey will provide useful pointers to future researchers wishing to correct this situation.
Mechanical properties of neurons represent a key factor that determines the functionality of neuronal cells and the formation of neural networks. The main source of mechanical stability for the cell is a biopolymer network of microtubules and actin filaments that form the main components of the cellular cytoskeleton. This biopolymer network is responsible for the growth of neuronal cells as they extend neurites to connect with other neurons, forming the nervous system. Here we present experimental results that combine atomic force microscopy (AFM) and fluorescence microscopy to produce systematic, high-resolution elasticity and fluorescence maps of cortical neurons. This approach allows us to apply external forces to neurons, and to monitor the dynamics of the cell cytoskeleton. We measure how the elastic modulus of neurons changes upon changing the ambient temperature, and identify the cytoskeletal components responsible for these changes. These results demonstrate the importance of taking into account the effect of ambient temperature when measuring the mechanical properties of cells.