Determining optimal cadence for an individual road cyclist from field data

The cadence that maximises power output developed at the crank by an individual cyclist is conventionally determined using a laboratory test. The purpose of this study was two-fold: (i) to show that such a cadence, which we call the optimal cadence, can be determined using power output, heart-rate, and cadence measured in the field and (ii) to describe methodology to do so. For an individual cyclist's sessions, power output is related to cadence and the elicited heart-rate using a non-linear regression model. Optimal cadences are found for two riders (83 and 70 revolutions per minute, respectively); these cadences are similar to the riders’ preferred cadences (82–92?rpm and 65–75?rpm). Power output reduces by approximately 6% for cadences 20?rpm above or below optimum. Our methodology can be used by a rider to determine an optimal cadence without laboratory testing intervention: the rider will need to collect power output, heart-rate, and cadence measurements from training and racing sessions over an extended period (>6 months); ride at a range of cadences within those sessions; and calculate his/her optimal cadence using the methodology described or a software tool that implements it

Reported Acquisition Practices of Australian Dog Owners

In Australia, the UK and the US dog ownership is prevalent with an estimated 40% ofAustralian households, 25% of UK households, and 50% of US households owning a dog. Onceacquired, a dog usually becomes a family companion so, unlike a faulty product, it can rarely bereturned or resold without some emotional impact on both the acquirer and the dog. Regarding thereality of dog relinquishment, there is a growing need for cross-disciplinary research that considershow dog owners are making their acquisition choices and, if prioritising different attributes, leads tomore optimal acquisition choices. This research collected data from 2840 dog owners via an onlinesurvey and examines how owners prioritised various attributes when acquiring their latest dog.The Pearson-Blotchky analysis of survey results show owners are split into two groups, with eachgroup prioritising different attributes or characteristics in their search for a new dog. The first groupare those dog owners who prioritised: the ability to rescue a dog, how compatible the dog wason the first meeting, and how compatible they believed the dog would be with their household.The second group are those owners who prioritised: a dog’s morphology, temperament predictability,and breeding practices. While each group prioritised different attributes, neither group madesubstantially more optimal acquisition choices in terms of overall satisfaction with the dog that theyultimately selected

Hawking temperature in the eternal BTZ black hole: an example of Holography in AdS spacetime

We review the relation between AdS spacetime in 1+2 dimensions and the BTZ black hole. Later we show that a ground state in AdS spacetime becomes a thermal state in the BTZ black hole. We show that this is true in the bulk and in the boundary of AdS spacetime. The existence of this thermal state is tantamount to say that the Unruh effect exists in AdS spacetime and becomes the Hawking effect for an eternal BTZ black hole. In order to make this we use the correspondence introduced in Algebraic Holography between algebras of quasi-local observables associated to wedges and doble cones regions in the bulk of AdS spacetime and its conformal boundary respectively. Also we give the real scalar quantum field as a concrete heuristic realization of this formalism.Comment: 29 page

Exploring the relationship between adolescent biological maturation, physical activity, and sedentary behaviour: A systematic review and narrative synthesis

Context: Across adolescence, there is a notable decline in physical activity in boys and girls. Maturational timing may be a risk factor for disengagement from physical activity and increased sedentary behaviours during adolescence. Objective: This systematic review aimed to summarise literature that examined the relationship between maturational timing, physical activity and sedentary behaviour in adolescents. Methods: Six electronic databases were searched for articles that assessed biological maturation and physical activity (including sports participation and active transportation) or sedentary behaviours in adolescents. Two reviewers conducted title, abstract, and full-text screening, reference and forward citation searches. Included articles were evaluated for quality using a standardised tool. A narrative synthesis was used to analyse the findings due to the heterogeneity of the studies. Results: Searches yielded 78 articles (64 unique studies) that met the inclusion criteria, representing 242,316 participants (153,179 unique). Studies ranged from 30.0% (low) to 91.7% (high) in quality. An inverse relationship between maturational timing and physical activity (in 50 and 60% of studies in boys and girls, respectively) and a positive relationship between maturational timing and sedentary behaviour (in 100% and 53% of studies in boys and girls, respectively) was most commonly reported. Evidence supporting an association between maturational timing, sports participation, and active transportation was inconsistent. Conclusions: While this review demonstrates some evidence for early maturational timing as a risk factor for disengagement from physical activity and increase in sedentary behaviours, the reviewed literature also demonstrates that this relationship is complex. Future research that tracks maturity-related variations in physical activity and sedentary behaviours over adolescence is warranted

Spatially valid proprioceptive cues improve the detection of a visual stimulus

Vision and proprioception are the main sensory modalities that convey hand location and direction of movement. Fusion of these sensory signals into a single robust percept is now well documented. However, it is not known whether these modalities also interact in the spatial allocation of attention, which has been demonstrated for other modality pairings. The aim of this study was to test whether proprioceptive signals can spatially cue a visual target to improve its detection. Participants were instructed to use a planar manipulandum in a forward reaching action and determine during this movement whether a near-threshold visual target appeared at either of two lateral positions. The target presentation was followed by a masking stimulus, which made its possible location unambiguous, but not its presence. Proprioceptive cues were given by applying a brief lateral force to the participant’s arm, either in the same direction (validly cued) or in the opposite direction (invalidly cued) to the on-screen location of the mask. The d′ detection rate of the target increased when the direction of proprioceptive stimulus was compatible with the location of the visual target compared to when it was incompatible. These results suggest that proprioception influences the allocation of attention in visual spac

In vitro production of bovine embryos derived from individual donors in the Corral® dish

Background: Since the identity of the embryo is of outmost importance during commercial in vitro embryo production, bovine oocytes and embryos have to be cultured strictly per donor. Due to the rather low yield of oocytes collected after ovum pick-up (OPU) per individual cow, oocyte maturation and embryo culture take place in small groups, which is often associated with inferior embryo development. The objective of this study was to improve embryonic development in small donor groups by using the Corral (R) dish. This commercial dish is designed for human embryo production. It contains two central wells that are divided into quadrants by a semi-permeable wall. In human embryo culture, one embryo is placed per quadrant, allowing individual follow-up while embryos are exposed to a common medium. In our study, small groups of oocytes and subsequently embryos of different bovine donors were placed in the Corral (R) dish, each donor group in a separate quadrant. Results: In two experiments, the Corral (R) dish was evaluated during in vitro maturation (IVM) and/or in vitro culture (IVC) by grouping oocytes and embryos of individual bovine donors per quadrant. At day 7, a significantly higher blastocyst rate was noted in the Corral (R) dish used during IVM and IVC than when only used during IVM (12.9% +/- 2.10 versus 22.8% +/- 2.67) (P < 0.05). However, no significant differences in blastocyst yield were observed anymore between treatment groups at day 8 post insemination. Conclusions: In the present study, the Corral (R) dish was used for in vitro embryo production (IVP) in cattle; allowing to allocate oocytes and/or embryos per donor. As fresh embryo transfers on day 7 have higher pregnancy outcomes, the Corral (R) dish offers an added value for commercial OPU/IVP, since a higher blastocyst development at day 7 is obtained when the Corral (R) dish is used during IVM and IVC

Male predominance of pneumonia and hospitalization in pandemic influenza A (H1N1) 2009 infection

<p>Abstract</p> <p>Background</p> <p>Pandemic influenza A (H1N1) disproportionately affects different age groups. The purpose of the current study was to describe the age and gender difference of pandemic influenza A (H1N1) cases that lead to pneumonia, hospitalization or ICU admission.</p> <p>Methods</p> <p>Data were collected retrospectively between May 2009 and December 2009. All of the diagnoses of H1N1 were confirmed by real-time reverse-transcription polymerase chain reaction (RT-PCR).</p> <p>Results</p> <p>During the study period there were 3402 cases of RT-PCR positive H1N1, among which 1812 were males and 1626 were adults (> 15 years of age). 6% (206/3402) of patients required hospitalization, 3.6% (122/3402) had infiltrates on chest radiographs, and 0.70% (24/3402) were admitted to intensive care unit (ICU). The overall fatality rate was 0.1% (4/3402). The rate of hospitalization was sharply increased in patients ≥ 50 years of age especially in male. Out of 122 pneumonia patients, 68.8% (84 patients) were male. Among the patients admitted to the ICU, 70.8% (17 patients) were male. Approximately 1 of 10 H1N1-infected patients admitted to the ICU were ≥ 70 years of age.</p> <p>Conclusions</p> <p>Among the confirmed cases of H1N1, the ICU admission rate was < 1% and the case fatality rate was 0.1%. Male had a significantly higher rate of pneumonia and hospital admission. These findings should be taken into consideration when developing vaccination and treatment strategies.</p

Opportunities and priorities for breast surgical research

The Breast Cancer Campaign Gap analysis (2013) established breast cancer research priorities without specific focus on surgical research nor the role of surgeons. The majority of breast cancer patients encounter a surgeon at diagnosis or during treatment, thus surgical involvement in design and delivery of high-quality research to improve patient care is critical. This review aims to identify opportunities and priorities for breast surgical research to complement the previous gap analysis

Assessing the usefulness of a novel MRI-based breast density estimation algorithm in a cohort of women at high genetic risk of breast cancer: the UK MARIBS study

Introduction Mammographic breast density is one of the strongest known risk factors for breast cancer. We present a novel technique for estimating breast density based on 3D T1-weighted Magnetic Resonance Imaging (MRI) and evaluate its performance, including for breast cancer risk prediction, relative to two standard mammographic density-estimation methods.Methods The analyses were based on MRI (n = 655) and mammography (n = 607) images obtained in the course of the UK multicentre magnetic resonance imaging breast screening (MARIBS) study of asymptomatic women aged 31 to 49 years who were at high genetic risk of breast cancer. The MRI percent and absolute dense volumes were estimated using our novel algorithm (MRIBview) while mammographic percent and absolute dense area were estimated using the Cumulus thresholding algorithm and also using a 21-point Visual Assessment scale for one medio-lateral oblique image per woman. We assessed the relationships of the MRI and mammographic measures to one another, to standard anthropometric and hormonal factors, to BRCA1/2 genetic status, and to breast cancer risk (60 cases) using linear and Poisson regression.Results MRI percent dense volume is well correlated with mammographic percent dense area (R = 0.76) but overall gives estimates 8.1 percentage points lower (P < 0.0001). Both show strong associations with established anthropometric and hormonal factors. Mammographic percent dense area, and to a lesser extent MRI percent dense volume were lower in BRCA1 carriers (P = 0.001, P = 0.010 respectively) but there was no association with BRCA2 carrier status. The study was underpowered to detect expected associations between percent density and breast cancer, but women with absolute MRI dense volume in the upper half of the distribution had double the risk of those in the lower half (P = 0.009).Conclusions The MRIBview estimates of volumetric breast density are highly correlated with mammographic dense area but are not equivalent measures; the MRI absolute dense volume shows potential as a predictor of breast cancer risk that merits further investigation

Exploiting the pathway structure of metabolism to reveal high-order epistasis

<p>Abstract</p> <p>Background</p> <p>Biological robustness results from redundant pathways that achieve an essential objective, e.g. the production of biomass. As a consequence, the biological roles of many genes can only be revealed through multiple knockouts that identify a <it>set </it>of genes as essential for a given function. The identification of such "epistatic" essential relationships between network components is critical for the understanding and eventual manipulation of robust systems-level phenotypes.</p> <p>Results</p> <p>We introduce and apply a network-based approach for genome-scale metabolic knockout design. We apply this method to uncover over 11,000 minimal knockouts for biomass production in an <it>in silico </it>genome-scale model of <it>E. coli</it>. A large majority of these "essential sets" contain 5 or more reactions, and thus represent complex epistatic relationships between components of the <it>E. coli </it>metabolic network.</p> <p>Conclusion</p> <p>The complex minimal biomass knockouts discovered with our approach illuminate robust essential systems-level roles for reactions in the <it>E. coli </it>metabolic network. Unlike previous approaches, our method yields results regarding high-order epistatic relationships and is applicable at the genome-scale.</p