Entanglement and Sources of Magnetic Anisotropy in Radical Pair-Based Avian Magnetoreceptors

One of the principal models of magnetic sensing in migratory birds rests on the quantum spin-dynamics of transient radical pairs created photochemically in ocular cryptochrome proteins. We consider here the role of electron spin entanglement and coherence in determining the sensitivity of a radical pair-based geomagnetic compass and the origins of the directional response. It emerges that the anisotropy of radical pairs formed from spin-polarized molecular triplets could form the basis of a more sensitive compass sensor than one founded on the conventional hyperfine-anisotropy model. This property offers new and more flexible opportunities for the design of biologically inspired magnetic compass sensors

Variable and changing trajectories in youth athlete development: further verification in advocating a long-term inclusive tracking approach.

Athlete development through adolescence can vary greatly because of maturational processes. For example, variation can be observed in anthropometric and fitness measures with later maturing individuals "catching up" their earlier maturing peers at later time points. This study examined a methodological issue concerning how best to assess anthropometric and fitness change (i.e., "across age categories" or "per year") relative to an age and skill-matched population (N = 1,172). Furthermore, it examined changes in anthropometric and fitness characteristics in 3 cases of youth rugby league players (aged 13-15) across a 2-year period. Findings identified the "per year" method as generating less deviated z-scores across anthropometric and fitness measures (e.g., mean change p < 0.001), suggesting less substantial change in case players relative to the population. When applied to additional players, z-score and radar graphs showed developmental variability and longitudinal change. The possibility of a "later maturing player" increasing anthropometric (e.g., height: player 4 = 3.3 cm; player 5 = 13.2 cm; and player 6 = 15.7 cm) and fitness (e.g., 30-m sprint: player 4 = -0.18 s, player 5 = -0.46 s, and player 6 = -0.59 s) characteristics compared with early maturing players was confirmed. Findings affirm the potential for variable and changing trajectories in adolescent athletes. Practical implications advocate a long-term inclusive tracking approach of athletes, the avoidance of (de)selection, and the reduction of a performance emphasis in adolescent stages of sport systems

Monitoring workloads in collision sports: External load measures alone may not provide the full picture

PURPOSE: To compare the external loads and external:internal load ratios (EL:IL) during match-play of adolescent collision sport athletes playing at both elite (i.e., academy) and sub-elite (i.e., school) standards. METHODS: Following ethics approval, seventeen elite adolescent male rugby union players (mean ± SD age = 17 ± 1 years) were recruited for this study. Global positioning system (GPS) locomotor (i.e., relative distance [RD; m·min-1], low speed activity [LSA; relative distance <61% maximum velocity [Vmax]], high speed running [HSR; relative distance ≥61% Vmax]), and accelerometer (relative PlayerLoadTM [RPL; AU·min-1], PLSLOW [relative accelerations <2 m·s-1], PLFAST [relative accelerations ≥2 m·s-1]) external loads, and session rating of perceived exertion (sRPE) internal load measures were obtained from 22 matches resulting in 86 match files (39 sub-elite and 47 elite match files; 5 ± 2 match files per subject). Perceptual wellbeing measures (i.e., fatigue, sleep quality, upper-body and lower-body soreness, stress, and mood) were also recorded using a 5-point Likert scale on the mornings pre- and post-match. Data were analysed using Cohen’s d effect sizes (d) and magnitude-based inferences. RESULTS: Differences in external loads were unclear between playing standards for RD (d = -0.2) and RPL (d = 0.0). However, subjects’ EL:IL were very likely lower during elite compared to sub-elite matches for both RD:sRPE (d = -1.0) and RPL:sRPE (d = -0.8), due to the very likely greater sRPE during elite matches (d = -1.1). There were unclear differences between sub-elite and elite matches for distribution of GPS and accelerometer variables (i.e., LSA, HSR, PLSLOW, and PLFAST; Table 1). Changes in total perceptual wellbeing were possibly greater following elite compared to sub-elite matches, with unclear differences for changes in sleep quality, lower-body soreness, stress and mood. However, changes in perceptual fatigue and upper-body soreness were both likely greater following elite matches. CONCLUSIONS: Adolescent rugby union players had similar locomotor and accelerometer external loads (i.e., RD, LSA, HSR, RPL, PLSLOW and PLFAST) during both elite and sub-elite standard matches. However, EL:IL was substantially reduced in higher standard matches, indicating a higher perception of effort for a given external load. Greater changes in perceptual fatigue and upper-body soreness following elite match-play may be related to greater magnitude of collision-based activity at higher playing standards. This may be due to the increased body mass and running velocities of opponents at higher playing standards, which may not be fully accounted for using external load measures alone. PRACTICAL APPLICATION: As collision sports require more than just movement and acceleration demands, the inclusion of subjective load measures (i.e., sRPE) or EL:IL may provide a further insight to the true demands of training or match-play than GPS and accelerometer data alone

Incident light orientation lets C4 monocotyledonous leaves make light work differently

Photosynthesis is an important driver of ecosystem sustainability in the face of climate change. Monocotyledonous crop species with C4 photosynthesis such as maize (Zea mays L; corn) and sugar cane are crucial for future food security and biofuel crop requirements, while C4 pasture grasses such as Paspalum are central to natural ecosystems. The global demand for corn will exceed that for wheat and rice by 2020, making it the world&#x27;s most important crop. Light-driven photosynthesis supports plant biomass production, but plants have also evolved safety valve mechanisms that attenuate the absorption of potentially lethal levels of excess light. The array of survival responses that enables leaves to evade photoinhibition is complex and involves chloroplast and leaf movement as well as the molecular rearrangements that facilitate thermal energy dissipation. Here we report a novel morphological mechanism that allows C4 monocotyledonous leaves to regulate photosynthesis independently on each surface with respect to incident light allowing better adaptation to water deficits and light stress. We show that under abaxial illumination as occurs when monocotyledonous leaves curl in response to water stress the stomata close and photosynthetic metabolism shuts down on the adaxial surface of C4 leaves but these parameters increase in function to the abaxial surface. We discuss how this regulation confers a survival advantage to the C4 relative to C3 leaves which are unable to regulate their dorso-ventral functions in relation to light

Approaches to Assessing Nutrient Coupling in Open Ocean Datasets

Nutrient coupling describes a process where the biogeochemical cycles of two elements are linked by being incorporated similarly into biomass. This paper uses data from the GEOTRACES GP16 cruise (Eastern Pacific Zonal Transect) to investigate the relationship between certain macronutrients generally coupled to trace elements in terms of their oceanic distributions with the notable exception of in an oxygen minimum zone: cadmium-phosphate and zinc-silicate. There are many methods applied to oceanographic data to correlate analyte concentrations; while they are often presented independently in literature, here we attempt to use them in conjunction for a more thorough interpretation. By compiling 1) depth profiles, 2) differences between the concentrations after applying a scale factor, and 3) direct comparisons of the analytes, greater insight into the correlations between coupled nutrients is achievable. Because the goal of studying this phenomenon is to learn about the underlying causes of these biogeochemical cycles, being able to characterize the decoupling in a way that is easy to visualize is extremely important to the efficacy of this area of research. Variation between results is elaborated on as a caution towards carefully considered and consistent data manipulation. Calculating a difference between the coupled analytes after applying a scaling factor provided the most useful information about decoupling

Influence of infection on the distribution patterns of NIH-Chronic Prostatitis Symptom Index scores in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS)

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a complex condition for which the etiological determinants are still poorly defined. To better characterize the diagnostic and therapeutic profile of patients, an algorithm known as UPOINT was created, addressing six major phenotypic domains of CP/CPPS, specifically the urinary (U), psycho-social (P), organ-specific (O), infection (I), neurological/systemic (N) and muscular tenderness (T) domains. An additional sexual dysfunction domain may be included in the UPOINT(S) system. The impact of the infection domain on the severity of CP/CPPS symptoms is a controversial issue, due to the contradictory results of different trials. The aim of the present retrospective study was to further analyze the extent to which a positive infection domain of UPOINTS may modify the pattern of CP/CPPS symptom scores, assessed with the National Institutes of Health-Chronic Prostatitis Symptom Index (NIH-CPSI). In a cohort of 935 patients that was divided on the basis of the presence or absence of prostatic infection, more severe clinical symptoms were shown by the patients with infection (median NIH total score: 24 versus 20 points in uninfected patients; P<0.001). Moreover, NIH-CPSI score distribution curves were shifted towards more severe symptoms in patients with a positive infection domain. Division of the patients into the six most prominent phenotypic clusters of UPOINTS revealed that the 'prostate infection-related sexual dysfunction' cluster, including the highest proportion of patients with evidence of infection (80%), scored the highest number of NIH-CPSI points among all the clusters. To assess the influence of the infection domain on the severity of patients' symptoms, all subjects with evidence of infection were withdrawn from the 'prostate infection-related sexual dysfunction' cluster. This modified cluster showed symptom scores significantly less severe than the original cluster, and the CPSI values became comparable to the scores of the five other clusters, which were virtually devoid of patients with evidence of infection. These results suggest that the presence of pathogens in the prostate gland may significantly affect the clinical presentation of patients affected by CP/CPPS, and that the infection domain may be a determinant of the severity of CP/CPPS symptoms in clusters of patients phenotyped with the UPOINTS system. This evidence may convey considerable therapeutic implications

Streaking temporal double slit interference by an orthogonal two-color laser field

We investigate electron momentum distributions from single ionization of Ar by two orthogonally polarized laser pulses of different color. The two-color scheme is used to experimentally control the interference between electron wave packets released at different times within one laser cycle. This intracycle interference pattern is typically hard to resolve in an experiment. With the two-color control scheme these features become the dominant contribution to the electron momentum distribution. Furthermore the second color can be used for streaking of the otherwise interfering wave packets establishing a which-way marker. Our investigation shows that the visibility of the interference fringes depends on the degree of the which-way information determined by the controllable phase between the two pulses.Comment: submitted to PR

Dermatoglyphics in childhood leukaemia: a guide to prognosis and aetiology?

The results of analysis of the dermatoglyphics of 152 children with acute lymphoblastic leukaemia (ALL) (and the first-degree relatives of 54 of them) contrast with those of 31 children with acute myeloblastic leukaemia (AML) (and the first-degree relatives of 25 of them). In ALL our findings suggest that neither genetic susceptibility nor an environmental factor, effective during the early antenatal period, is of aetiological importance; but the response to treatment, assessed as length of first remission, was found to be related to the amount of fingertip pattern. This may have clinical application. In AML there is evidence of a genetically determined factor carrying a high risk of the development of the disease, in that a member of each of 5 different families of the 25 studied bore a rare hypothenar pattern, compared with none in 75 control families. No dermatoglyphic features were of prognostic significance in AML