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Central nervous system tumours represent one of the most lethal cancer types, particularly among children1. Primary treatment includes neurosurgical resection of the tumour, in which a delicate balance must be struck between maximizing the extent of resection and minimizing risk of neurological damage and comorbidity2,3. However, surgeons have limited knowledge of the precise tumour type prior to surgery. Current standard practice relies on preoperative imaging and intraoperative histological analysis, but these are not always conclusive and occasionally wrong. Using rapid nanopore sequencing, a sparse methylation profile can be obtained during surgery4. Here we developed Sturgeon, a patient-agnostic transfer-learned neural network, to enable molecular subclassification of central nervous system tumours based on such sparse profiles. Sturgeon delivered an accurate diagnosis within 40 minutes after starting sequencing in 45 out of 50 retrospectively sequenced samples (abstaining from diagnosis of the other 5 samples). Furthermore, we demonstrated its applicability in real time during 25 surgeries, achieving a diagnostic turnaround time of less than 90 min. Of these, 18 (72%) diagnoses were correct and 7 did not reach the required confidence threshold. We conclude that machine-learned diagnosis based on low-cost intraoperative sequencing can assist neurosurgical decision-making, potentially preventing neurological comorbidity and avoiding additional surgeries.

•A brief historical summary of BRICS countries and the BRICS Council of Exercise and Sport Science (BRICSCESS) is presented.•BRICSCESS functions to facilitate the accomplishment of the various tasks such as to establish links between institutions and organizations; establish an active and sustainable future leader/volunteer program; promote collaboration in research, teaching, and mentoring between international scientists; develop, organize, and promote conferences, seminars, workshops, symposiums, round-table discussions and training courses; and publish new scientific information related to exercise, physical activity, sports science, lifestyle management, and nutrition.•A central task of BRICSCESS is to establish an active and sustainable future leader/volunteer program for mentoring junior scholars within the exercise science and lifestyle management fields.

AbstractThe objective of the study was to determine the effect of fatigue on the percentage of time sevens rugby players spend on the movement activities during the two different halves of match play and to compare the percentage of time starter and substitute players spend on high and low-intensity movement activities. Sixty-one time-motion analyses data-sets of twelve (12) senior male elite Zimbabwean rugby sevens players with a mean age of 27.8 years were gathered at two International Sevens rugby tournaments. Time-motion analysis data were captured at 10 Hz with a minimaxX GPS device. Results indicated that starter players covered a significantly greater distance (r = 0.26) than substitute players. However, substitute players covered a significantly greater relative distance (distance per minute) (r = 0.33) than the starter players. Hence, the substitute players had less rest during match play and therefore a higher work-to-rest ratio than the starter players. No large practically significant differences found between the high intensity movement activities of the players during the two halves of match play, suggesting that fatigue did not affect the players’ movement activities. The results therefore suggest that the use of substitute players may support the ability of teams to increase the players work rate.

Few studies have examined objective physical activity in relation to 24 h ambulatory blood pressure (BP). We aimed to assess the association of 7-day objectively measured habitual physical activity with ambulatory BP in a sample of African and Caucasian school teachers (n=216, age 49.7 years) from the sympathetic activity and blood pressure in Africans prospective cohort study. Hypertension (ambulatory systolic BP⩾130 and/or diastolic BP⩾80 mm Hg) was prevalent in 53.2% of the sample, particularly in black Africans. The hypertensive group spent significantly more awake time in sedentary activity (51.5% vs 40.8% of waking hours, P=0.001), as well as doing less light- (34.1% vs 38.9%, P=0.043) and moderate-intensity (14.0% vs 19.7%, P=0.032) activities compared with normotensives, respectively. In covariate adjusted models, light-intensity activity time was associated with lower 24 h and daytime ambulatory systolic BP (β=−0.15, 95% confidence interval (CI): −0.26, −0.05, P=0.004; β=−0.14, CI: −0.24, −0.03, P=0.011) and diastolic BP (β=−0.14, CI: −0.25, −0.03, P=0.015; β=−0.13, CI: −0.24, −0.01, P=0.030), as well as resting systolic BP (β=−0.13, CI: −0.24, −0.01, P=0.028). Sedentary time was associated only with 24 h systolic BP (β=0.12; CI: 0.01, 0.22), which was largely driven by night-time recordings. Participants in the upper sedentary tertile were more likely to be ‘non-dippers’ (odds ratio=2.11, 95% CI: 0.99, 4.46, P=0.052) compared with the lowest sedentary tertile. There were no associations between moderate to vigorous activity and BP. In conclusion, objectively assessed daily light physical activity was associated with ambulatory BP in a mixed ethnic sample.

Context.

Context. Observations during the first long run (~150 days) in the exo-planet field of CoRoT increase the number of G-K giant stars for which solar-like oscillations are observed by a factor of 100. This opens the possibility to study the characteristics of their oscillations in a statistical sense.

Context. γDor stars are excellent targets for asteroseismology since the gravity modes present in these stars probe the deep stellar interiors. Mode identification will improve the knowledge of these stars considerably.

Context.BL Cam is an extreme metal-deficient field high-amplitude SX Phe-type variable where a very complex frequency spectrum is detected, with a number of independent nonradial modes excited, unusual among the high-amplitude pulsators in the Lower Classical Instability Strip.

Context.Solar-like oscillations have been discovered in a few red giants, including ϵOph, through spectroscopy. Acoustic modes around 60 μHz were clearly seen in this star, but daily aliasing of the groundbased data made it impossible to unambiguously isolate the p-mode frequencies in the eigenspectrum, and hence the correct value of the large spacing, to asteroseismically constrain the mass of this pulsating star.

Context.This is the first step in a project to combine studies of eclipsing binaries and oscillating stars to probe the interior of Blue Stragglers (BS). This may imply a way to discriminate observationally between different birth mechanisms of BS stars.

Aims.We selected a large sample of O-B stars that were considered as (candidate) slowly pulsating B, βCep, and Maia stars after the analysis of their hipparcosdata. We analysed our new seven passband genevadata collected for these stars during the first three years of scientific operations of the mercatortelescope. We performed a frequency analysis for 28 targets with more than 50 high-quality measurements to improve their variability classification. For the pulsating stars, we tried both to identify the modes and to search for rotationally split modes.

Context.So far, red giant oscillations have been studied from radial velocity and/or light curve variations, which reveal frequencies of the oscillation modes. To characterise radial and non-radial oscillations, line profile variations are a valuable diagnostic. Here we present for the first time a line profile analysis of pulsating red giants, taking into account the small line profile variations and the predicted short damping and re-excitation times. We do so by modelling the time variations in the cross correlation profiles in terms of oscillation theory.

We present a study of absorption line-profile variations in early-B type near-main-sequence stars without emission lines. We have surveyed a total of 171 bright stars using the Nordic Optical Telescope (NOTSA), William Herschel Telescope (ING) and Coudé Auxiliary Telescope (ESO). Our sample contains 75% of all O9.5-B2.5 III-V non-emission-line stars brighter than 5.5 mag. We obtained high signal-to-noise, high-resolution spectra of the SiIII λ4560 triplet – for 125 stars of our sample we obtained more than one spectrum – and examined these for pulsational-like line-profile variations and/or structure.
We conclude that about half of our sample stars show evidence for line-profile variations (LPV). We find evidence for LPV in about 65% of our sample stars brighter than $V=5.5$. For stars with rotational broadening $V\sin i \sim100$km s-1, we find evidence for LPV in about 75% of the cases. We argue that it is likely that these LPV are of pulsational origin, and that hence more than half of the solar-neighbourhood O9.5-B2.5 III-V stars is pulsating in modes that can be detected with high-resolution spectroscopy. We detected LPV in 64 stars previously unknown to be pulsators, and label these stars as new βCep candidates. We conclude that there is no obvious difference in incidence of (pulsational) LPV for early-B type near-main-sequence stars in binaries or in OB associations, with respect to single field stars.

We present the discovery of solar-like oscillations in time-series of the G9.5 red giant εOphiuchi. The data were obtained with the CORALIE spectrograph at the 1.2 m Swiss telescope in La Silla and the ELODIE spectrograph at the 1.93 m telescope at the Observatoire de Haute Provence. Periodic variations can be observed in the radial velocity time series of individual nights. In the power spectrum of the radial velocity time series there is a clear power excess around 60 μHz, and several individual oscillation frequencies can be distinguished. Our auto-correlation and comb response analysis reveals a large separation of either 4.8 μHz or (its 11.57 μHz alias) 6.7 μHz. We estimate the position of εOph in the HR diagram, and verify whether CESAM shell hydrogen-burning stellar models exist that can reproduce the observed frequency separation.

We present the results of the mode identification for a sample of 7 bright southern slowly pulsating B stars showing one pulsation frequency in the $\lambda\lambda$413 nm Si II profiles. We combined the results from (1) the method of photometric amplitudes; (2) the moment method; and (3) the amplitude and phase variation across the profile to search for the $\ell$and mvalues of the modes best fitting the data. It is the first time that the applicability of these techniques is tested to a sample of main-sequence g-mode pulsators. Combining the moment method with the amplitude and phase variations across the observed line profile gives an improvement in spectroscopic identification of low degree $\ell$g-mode pulsations. Using the variations of the higher order even moments ${\langle v^4\rangle}$and ${\langle v^6\rangle}$of the moment method solutions can also help. For HD 181558, HD 24587, HD 140873 and HD 177863, the photometric and spectroscopic results are compatible and point towards $(\ell,m)$= (1, +1) sectoral modes. For HD 215573, HD 53921 and HD 92287, the results are inconclusive. Our proposed methodology for mode identification is also applicable to γDoradus stars.

We gathered long-term multicolour Geneva $UB_1BB_2V_1VG$photometric and high-resolution ($R=40\,000$) spectroscopic data of the two $\gamma\,$Doradus stars HD 12901 and HD 48501. The photometry reveals three frequencies for each of the two stars: $f_1=1.21563$c d-1, $f_2=1.39594$c d-1and $f_3=2.18636$c d-1for HD 12901 and $f_1=1.09408$c d-1, $f_2=1.29054$c d-1and $f_3=1.19924$c d-1for HD 48501. The photometric amplitude is each time largest in the Geneva B1filter and the variations in all the different filters are perfectly in phase within the measurement errors. Mode identification points out that the six modes are all $\ell=1$modes and that the non-adiabatic temperature variations are extremely small, in contradiction to current theoretical predictions. Our spectra show that all the observed frequencies are intrinsic to the stars and cannot be due to binarity. We detect clear line-profile variations at low amplitude (${<}1\,$km s-1) due to the oscillations of both targets. The estimated $v\sin\,i$from the spectra are ${\sim}53\,$km s-1for HD 12901 and ${\sim}29\,$km s-1for HD 48501. It is at present unclear if the triplet-like structure for HD 48501 is the consequence of rotational splitting or of the large separation expected for high-order gravity modes in the asymptotic regime.

We perform seismic modelling of the massive $\beta\,$Cep star EN Lacertae. The starting point of our analysis is the spectroscopic mode identification recently performed. To this, we add a new updated photometric mode identification based upon a non-adiabatic description of the eigenfunctions in the outer atmosphere. Both mode identifications agree and this allows us to fine-tune the stellar parameters of EN Lacertae with unprecedented precision. This is done by producing a huge amount of stellar models with different parameters and selecting those that fulfill the frequency values and the mode identification. Our study is the first one of its kind in which a reconcilation between observed pulsational characteristics and theoretical models can be achieved at a level that allows accurate determination of the basic stellar parameters of a massive oscillator. We derive a mass of $M=9.62\pm 0.11\,M_\odot$and an age of 15.7 million years if we assume that convective overshooting does not occur.

We present an improved version of the method of photometric mode identification of Heynderickx et al. ([CITE]). Our new version is based on the inclusion of precise non-adiabatic eigenfunctions determined in the outer stellar atmosphere according to the formalism recently proposed by Dupret et al. ([CITE]). Our improved photometric mode identification technique is therefore no longer dependent on ad hoc parameters for the non-adiabatic effects. It contains the complete physical conditions of the outer atmosphere of the star, provided that rotation does not play a key role. We apply our method to the two slowly pulsating B stars HD 74560 and HD 138764 and to the ßCephei star EN (16) Lac. Besides identifying the degree $\ell$of the pulsating stars, our method is also a tool for improving the knowledge of stellar interiors and atmospheres, by imposing constraints on parameters such as the metallicity and the mixing-length parameter a(a procedure we label non-adiabatic asteroseismology).

We perform for the first time spectroscopic mode identification in the eclipsing binary $\beta\,$Cephei star EN (16) Lac. This mode identification is based upon a time series of 942 line profiles of the He I $\lambda\lambda$6678 Å line in its spectrum. All three known frequencies $f_1, f_2, f_3$of the star are present in the line-profile variations, but we failed to find additional modes. Using different identification methods we find conclusive evidence for the radial nature of the main mode and for the $\ell=2, m=0$identification of the mode with frequency f2. A unique identification of the third mode is not possible from the spectra, but we do derive that $\ell_3<3$. Fits to the amplitude and phase variability of the modes imply a rotation frequency between 0.1 and 0.4 c d-1. The star's rotation axis is not aligned with the orbital axis.

In this study, we compute theoretical line profiles of a non-radially pulsating star, taking the non-adiabatic effects into account. These non-adiabatic effects are especially important in the atmosphere, where the spectral lines are formed, and must be accounted for. In this first paper of the series, we present a new treatment of the perturbed thermal and dynamical equations in the atmosphere of a pulsating star. We apply our formalism to the computation of non-adiabatic eigenfunctions in a typical βCephei star with low order p-modes and in a typical slowly pulsating B star with high-order g-modes.

We investigate to what extent non-adiabatic temperature variations at the surface of slowly rotating non-radially pulsating βCephei stars and slowly pulsating B stars affect silicon line profile variations. We use the non-adiabatic amplitudes of the effective temperature and gravity variation presented in Dupret et al. ([CITE]), together with a Kurucz intensity grid, to compute time series of line profile variations. Our simulations point out that the line shapes do not change significantly due to temperature variations. We find equivalent width variations of at most two percent of the mean equivalent width. We confront our results with observational equivalent width variations and with photometrically obtained effective temperature variations.

We present a new spectroscopic study of the δScuti star 20 CVn in order to solve the controversy on the type of pulsation mode of this object. The spectra were obtained at the Observatoire de Haute-Provence, with the Echelle spectrograph ELODIE. Using the correlation configuration of the instrument, sinusoidal moment variations are clearly detected, with a frequency in perfect agreement with the photometric one. Using the moment method, we conclude that only the radial mode is able to explain the observed moment variations and leads to a good fit to the observed line profiles. The new data thus allow us to confirm the photometric results, i.e. 20 CVn exhibits a monoperiodic radial pulsation.

We present a total time series of high signal-to-noise, high-resolution spectra of the SiIII $\lambda 4552.6$, $\lambda 4567.8$and $\lambda 4574.8$Ålines of the fast-rotating, spectroscopic binary and βCephei star κScorpii. Among this data set is a sample of 422 spectra of intensive monitoring during eight subsequent nights in July 1997. We find variability of the line profiles on two time-scales: a variation of several months as a result of the orbital motion and rapid variations of a few hours, which are explained in terms of non-radial pulsation modes. From the total dataset, covering a time span of 9 years, we derive for the first time the orbital parameters of κScorpii and find an orbital period of 195 days. The complex patterns on the grayscale representations of the residual SiIII $\lambda 4552.6$Åprofiles with respect to the average profile point towards more than one (non-axisymmetric) pulsation mode. A frequency analysis of the three normalised velocity moments confirms the main period of 4.80 hours and the second period of 4.93 hours, which were previously derived from photometric data. We attempt an identification of the pulsation modes by means of the moment method and line-profile fitting and find that κScorpii pulsates in a main prograde sectoral mode of degree 1 or 2 and in an additional tesseral mode for which $l = 5$, $m = 1$are the most likely wavenumbers. In the variations of the line profiles we find indications for the presence of additional pulsation modes.

Abstract: The aim was to determine receiver operating characteristic (ROC) neck circumference (NC) cut offs best associated with the metabolic syndrome (MetS) in a South African cohort. We included 409 urban Africans and Caucasians and stratified them into gender and age groups (25–45 years; 45–65 years). Measurements included anthropometric, fasting overnight urine and biological markers for the MetS (systolic and diastolic blood pressure, glucose, triglycerides, and high density lipoprotein). ROC analysis determined pathological (NC) cut-points of 39 and 35 cm for young and older African men; 32 and 35 cm for young and old African women; 40 and 41 cm for Caucasian men; 34 and 33 cm for Caucasian women. Pathological NC cut-points significantly predicted MetS in all ethnic–gender–age groups except in African women (ORs 2.3–5.4; 95% CI 1.36–16.5). Multiple regression analyses revealed that MetS prevalence and ROC cut-points were not associated with renal impairment in any groups. ROC NC cut-points demonstrated that NC may be used as an additional anthropometric marker to predict the MetS in a South African cohort but not in African women.

Context. The detection with CoRoT of solar-like oscillations in nearly 800 red giants in the first 150-days long observational run paves the way for detailed studies of populations of galactic-disk red giants.Aims. We investigate which information on the observed population can be recovered by the distribution of the observed seismic constraints: the frequency of maximum oscillation power (?max) and the large frequency separation (??).Methods. We propose to use the observed distribution of ?max?and of ?? as a tool for investigating the properties of galactic red-giant stars through comparison with simulated distributions based on synthetic stellar populations.Results. We can clearly identify the bulk of the red giants observed by CoRoT as red-clump stars, i.e. post-flash core-He-burning stars. The distribution of ?max?and of ?? gives us access to the distribution of the stellar radius and mass, and thus represent a most promising probe of the age and star formation rate of the disk, and of the mass-loss rate during the red-giant branch.Conclusions. CoRoT observations are supplying seismic constraints for the most populated class of He-burning stars in the galactic disk. This opens a new access gate to probing the properties of red-giant stars that, coupled with classical observations, promises to extend our knowledge of these advanced phases of stellar evolution and to add relevant constraints to models of composite stellar populations in the Galaxy.

Context. The influence of binarity on the late stages of stellar evolution remains an open issue.Aims. While the first binary post-AGB stars were serendipitously discovered, the distinct characteristics of their spectral energy distribution (SED) allowed us to launch a more systematic search for binaries. We selected post-AGB objects, which exhibit a broad dust excess starting either at H or?K, pointing to the presence of a gravitationally bound dusty disc in the system. We initiated an extensive multiwavelength study of those systems and here report on our radial velocity and photometric monitoring results for six stars of early F?type, which are pulsators of small amplitude.Methods. To determine the radial velocity of low signal-to-noise ratio time-series data, we constructed dedicated autocorrelation masks based on high signal-to-noise ratio spectra, used in our published chemical studies. The radial velocity variations were analysed in detail to differentiate between pulsational variability and variability caused by orbital motion. When available, the photometric monitoring data were used to complement the time series of radial velocity data and to establish the nature of the pulsation. Finally, orbital minimalisation was performed to constrain the orbital elements.Results. All of the six objects are binaries with orbital periods ranging from 120 to 1800?days. Five systems have non-circular orbits. The mass functions range from 0.004 to 0.57?M?and the companions are probably unevolved objects of (very) low initial mass. We argue that these binaries must have evolved through a phase of strong binary interaction when the primary was a cool supergiant. Although the origin of the circumstellar disc is not well understood, the disc is generally believed to have formed during this strong interaction phase. The eccentric orbits of these highly evolved objects remain poorly understood. In one object, the line-of-sight grazes the edge of the puffed-up inner rim of the disc.Conclusions. These results corroborate our earlier statement that evolved objects in binary stars create a Keplerian dusty circumbinary disc. With the measured orbits and mass functions, we conclude that the circumbinary discs seem to have a major impact on the evolution of a significant fraction of binary systems.

The rate of tungsten transport in a cylindrical gas-filled incandescent lamp has been calculated. The theory is based on the assumptions of Langmuir and Fonda. In this model the transport has been determined by the rate of diffusion through the stationary Langmuir zone. The diameter of that zone has been calculated according to the method of Elenbaas. In the present method the position dependence of the diffusion coefficient is introduced. A result is that the rate of tungsten transport as a function of the envelope diameter has a minimum. The inner envelope diameter is then equal to that of the Langmuir zone. The theory gives also an easy method of calculating the working pressure of the inert gas from the filling pressure.