Isotope shift in the Sulfur electron affinity: observation and theory

The electron affinities eA(S) are measured for the two isotopes 32S and 34S (16752.9753(41) and 16752.9776(85) cm-1, respectively). The isotope shift in the electron affinity is found to be positive, eA(34S)-eA(32S) = +0.0023(70) cm-1, but the uncertainty allows for the possibility that it may be either "normal" (eA(34S) > eA(32S)) or "anomalous" (eA(34S) < eA(32S)). The isotope shift is estimated theoretically using elaborate correlation models, monitoring the electron affinity and the mass polarization term expectation value. The theoretical analysis predicts a very large specific mass shift that counterbalances the normal mass shift and produces an anomalous isotope shift, eA(34S)-eA(32S) = - 0.0053(24) cm-1. The observed and theoretical residual isotope shifts agree with each other within the estimated uncertainties.Comment: 15 pages, 4 figure

Régions et frontières de téléphonie mobile en Belgique et dans l’aire métropolitaine bruxelloise

Dans cet article, nous explorons l’existence de régions et de frontières en Belgique au moyen d’un jeu de données original de plus de 200 millions de communications mobiles et d’une méthode mathématique qui permet de découper de manière naturelle et automatique des réseaux en groupes cohérents. Une géographie des communications mobiles est ainsi proposée sur la base de la fréquence relative des communications ainsi que de leur durée moyenne. Dans le cas de la fréquence relative des communications, nous obtenons une carte de Belgique composée de 17 groupes ou « bassins téléphoniques » spatialement bien ancrés, aux communes étonnamment toutes adjacentes. Sur cette première carte, le bassin de Bruxelles est le seul qui traverse largement la frontière linguistique et couvre les trois régions institutionnelles du pays. Dans le cas de la durée moyenne des communications, nous obtenons un groupe au nord et un groupe au sud du pays. Ces deux groupes concentrent en leur sein près de 98 % des appels téléphoniques ; seuls 2 % des communications passent d’un groupe à l’autre. Le groupe du sud comprend les 19 communes de Bruxelles, toutes les communes de la région Wallonne ainsi que huit communes à facilités situées en région flamande. En particulier, toutes les communes à facilités de la périphérie bruxelloise (à l’exception de Wemmel) font partie du groupe du sud du pays.In dit artikel onderzoeken we het bestaan van regio’s en van grenzen in België op basis van een originele databank die gegevens bevat van meer dan 200 miljoen mobiele telefoongesprekken en van een wiskundige methode die toelaat op automatische en natuurlijke wijze netwerken in coherente groepen te verdelen. Op die manier kan een geografie van mobiel telefoonverkeer voorgesteld worden op basis van de relatieve frequenties van de telefoongesprekken en hun gemiddelde duur. Als we de relatieve frequentie van de gesprekken als criterium gebruiken, krijgen we een kaart van België die bestaat uit 17 groepen of “telefoonbassins” die ruimtelijk verankerd zijn in gemeenten die allemaal verbazend aangrenzend zijn. Op deze eerste kaart is het enkel het bassin van Brussel dat de taalgrens nadrukkelijk doorbreekt en de drie institutionele gewesten van het land bedekt. Als we de gemiddelde duur van de gesprekken als criterium hanteren, krijgen we één groep in het noorden en één groep in het zuiden van het land. Binnen deze twee groepen vindt ongeveer 98% van de gesprekken plaats; slechts 2% van het telefoonverkeer gaat van de ene groep naar de andere. De zuidelijke groep bevat de 19 Brusselse gemeenten, alle gemeenten van het Waals Gewest en acht faciliteitengemeenten die in het Vlaams Gewest liggen. Het is opmerkelijk dat alle faciliteitengemeenten van de Brusselse rand (met uitzondering van Wemmel) deel uitmaken van de groep van het zuiden van het land.In this article, we examine the existence of regions and borders in Belgium by means of an original data set of more than 200 million mobile communications and a mathematical method which allows networks to be divided into coherent groups in a natural and automatic manner. A geography of mobile communications is thus proposed based on the relative frequency of communications as well as their average duration. In the case of the relative frequency of communications, we obtain a map of Belgium composed of 17 groups or “telephone areas” that each contain only adjacent municipalities. On this first map, the area of Brussels is the only one which runs across the linguistic border and covers the three institutional regions of the country. In the case of the average duration of communications, we obtain a group in the north and a group in the south of the country. These two groups concentrate within themselves almost 98% of telephone calls; only 2% of communications are from one group to the other. The group in the south includes the 19 municipalities of Brussels, all of the municipalities in the Walloon region as well as eight municipalities with facilities located in the Flemish region. In particular, all of the municipalities with facilities in the outskirts of Brussels (with the exception of Wemmel) are part of the group in the south of the country

Regio’s en grenzen van mobiele telefonie in België en in het Brussels stadsgewest

In dit artikel onderzoeken we het bestaan van regio’s en van grenzen in België op basis van een originele databank die gegevens bevat van meer dan 200 miljoen mobiele telefoongesprekken en van een wiskundige methode die toelaat op automatische en natuurlijke wijze netwerken in coherente groepen te verdelen. Op die manier kan een geografie van mobiel telefoonverkeer voorgesteld worden op basis van de relatieve frequenties van de telefoongesprekken en hun gemiddelde duur. Als we de relatieve frequentie van de gesprekken als criterium gebruiken, krijgen we een kaart van België die bestaat uit 17 groepen of “telefoonbassins” die ruimtelijk verankerd zijn in gemeenten die allemaal verbazend aangrenzend zijn. Op deze eerste kaart is het enkel het bassin van Brussel dat de taalgrens nadrukkelijk doorbreekt en de drie institutionele gewesten van het land bedekt. Als we de gemiddelde duur van de gesprekken als criterium hanteren, krijgen we één groep in het noorden en één groep in het zuiden van het land. Binnen deze twee groepen vindt ongeveer 98% van de gesprekken plaats; slechts 2% van het telefoonverkeer gaat van de ene groep naar de andere. De zuidelijke groep bevat de 19 Brusselse gemeenten, alle gemeenten van het Waals Gewest en acht faciliteitengemeenten die in het Vlaams Gewest liggen. Het is opmerkelijk dat alle faciliteitengemeenten van de Brusselse rand (met uitzondering van Wemmel) deel uitmaken van de groep van het zuiden van het land.Dans cet article, nous explorons l’existence de régions et de frontières en Belgique au moyen d’un jeu de données original de plus de 200 millions de communications mobiles et d’une méthode mathématique qui permet de découper de manière naturelle et automatique des réseaux en groupes cohérents. Une géographie des communications mobiles est ainsi proposée sur la base de la fréquence relative des communications ainsi que de leur durée moyenne. Dans le cas de la fréquence relative des communications, nous obtenons une carte de Belgique composée de 17 groupes ou « bassins téléphoniques » spatialement bien ancrés, aux communes étonnamment toutes adjacentes. Sur cette première carte, le bassin de Bruxelles est le seul qui traverse largement la frontière linguistique et couvre les trois régions institutionnelles du pays. Dans le cas de la durée moyenne des communications, nous obtenons un groupe au nord et un groupe au sud du pays. Ces deux groupes concentrent en leur sein près de 98 % des appels téléphoniques ; seuls 2 % des communications passent d’un groupe à l’autre. Le groupe du sud comprend les 19 communes de Bruxelles, toutes les communes de la région Wallonne ainsi que huit communes à facilités situées en région flamande. En particulier, toutes les communes à facilités de la périphérie bruxelloise (à l’exception de Wemmel) font partie du groupe du sud du pays.In this article, we examine the existence of regions and borders in Belgium by means of an original data set of more than 200 million mobile communications and a mathematical method which allows networks to be divided into coherent groups in a natural and automatic manner. A geography of mobile communications is thus proposed based on the relative frequency of communications as well as their average duration. In the case of the relative frequency of communications, we obtain a map of Belgium composed of 17 groups or “telephone areas” that each contain only adjacent municipalities. On this first map, the area of Brussels is the only one which runs across the linguistic border and covers the three institutional regions of the country. In the case of the average duration of communications, we obtain a group in the north and a group in the south of the country. These two groups concentrate within themselves almost 98% of telephone calls; only 2% of communications are from one group to the other. The group in the south includes the 19 municipalities of Brussels, all of the municipalities in the Walloon region as well as eight municipalities with facilities located in the Flemish region. In particular, all of the municipalities with facilities in the outskirts of Brussels (with the exception of Wemmel) are part of the group in the south of the country

Regions and borders of mobile telephony in Belgium and in the Brussels metropolitan zone

In this article, we examine the existence of regions and borders in Belgium by means of an original data set of more than 200 million mobile communications and a mathematical method which allows networks to be divided into coherent groups in a natural and automatic manner. A geography of mobile communications is thus proposed based on the relative frequency of communications as well as their average duration. In the case of the relative frequency of communications, we obtain a map of Belgium composed of 17 groups or “telephone areas” that each contain only adjacent municipalities. On this first map, the area of Brussels is the only one which runs across the linguistic border and covers the three institutional regions of the country. In the case of the average duration of communications, we obtain a group in the north and a group in the south of the country. These two groups concentrate within themselves almost 98% of telephone calls; only 2% of communications are from one group to the other. The group in the south includes the 19 municipalities of Brussels, all of the municipalities in the Walloon region as well as eight municipalities with facilities located in the Flemish region. In particular, all of the municipalities with facilities in the outskirts of Brussels (with the exception of Wemmel) are part of the group in the south of the country.Dans cet article, nous explorons l’existence de régions et de frontières en Belgique au moyen d’un jeu de données original de plus de 200 millions de communications mobiles et d’une méthode mathématique qui permet de découper de manière naturelle et automatique des réseaux en groupes cohérents. Une géographie des communications mobiles est ainsi proposée sur la base de la fréquence relative des communications ainsi que de leur durée moyenne. Dans le cas de la fréquence relative des communications, nous obtenons une carte de Belgique composée de 17 groupes ou « bassins téléphoniques » spatialement bien ancrés, aux communes étonnamment toutes adjacentes. Sur cette première carte, le bassin de Bruxelles est le seul qui traverse largement la frontière linguistique et couvre les trois régions institutionnelles du pays. Dans le cas de la durée moyenne des communications, nous obtenons un groupe au nord et un groupe au sud du pays. Ces deux groupes concentrent en leur sein près de 98 % des appels téléphoniques ; seuls 2 % des communications passent d’un groupe à l’autre. Le groupe du sud comprend les 19 communes de Bruxelles, toutes les communes de la région Wallonne ainsi que huit communes à facilités situées en région flamande. En particulier, toutes les communes à facilités de la périphérie bruxelloise (à l’exception de Wemmel) font partie du groupe du sud du pays.In dit artikel onderzoeken we het bestaan van regio’s en van grenzen in België op basis van een originele databank die gegevens bevat van meer dan 200 miljoen mobiele telefoongesprekken en van een wiskundige methode die toelaat op automatische en natuurlijke wijze netwerken in coherente groepen te verdelen. Op die manier kan een geografie van mobiel telefoonverkeer voorgesteld worden op basis van de relatieve frequenties van de telefoongesprekken en hun gemiddelde duur. Als we de relatieve frequentie van de gesprekken als criterium gebruiken, krijgen we een kaart van België die bestaat uit 17 groepen of “telefoonbassins” die ruimtelijk verankerd zijn in gemeenten die allemaal verbazend aangrenzend zijn. Op deze eerste kaart is het enkel het bassin van Brussel dat de taalgrens nadrukkelijk doorbreekt en de drie institutionele gewesten van het land bedekt. Als we de gemiddelde duur van de gesprekken als criterium hanteren, krijgen we één groep in het noorden en één groep in het zuiden van het land. Binnen deze twee groepen vindt ongeveer 98% van de gesprekken plaats; slechts 2% van het telefoonverkeer gaat van de ene groep naar de andere. De zuidelijke groep bevat de 19 Brusselse gemeenten, alle gemeenten van het Waals Gewest en acht faciliteitengemeenten die in het Vlaams Gewest liggen. Het is opmerkelijk dat alle faciliteitengemeenten van de Brusselse rand (met uitzondering van Wemmel) deel uitmaken van de groep van het zuiden van het land

Real-time In-Situ Passive Acoustic Array Beamforming from the AutoNaut Wave-Propelled Uncrewed Surface Vessel

This article presents the first demonstration of beamforming, detection, and bearing estimation of an underwater acoustic source from an eight-element thin line hydrophone array towed behind the AutoNaut wave-propelled uncrewed surface vessel. This has been achieved in situ and in real time during an experimental sea trial off the coast of Plymouth, U.K. A controlled acoustic source was towed from a support vessel while emitting seven tonals with frequencies between 480&amp;#x2013;1630&amp;#x00A0;Hz and source levels between 93&amp;#x2013;126&amp;#x00A0;dB. This allowed the detection performance of the array to be assessed and demonstrated for an acoustic source with known bearing and range. In postprocessing, the shape of the array was estimated using a cubic spline model, exploiting measurements from pressure and three-axis compass sensors integrated at each end of the array. The beamforming was repeated using the estimated array shape to infer the hydrophone positions, which resulted in a median improvement of 0.38&amp;#x00A0;dB and maximum of 5.8&amp;#x00A0;dB in the MUSIC beamforming output, and a potential reduction in the left/right bearing estimation ambiguities. The outcomes of this work demonstrate that the AutoNaut is an effective platform for towed array passive acoustic monitoring.</p

A low energy neutrino factory with non-magnetic detectors

We show that a very precise neutrino/anti-neutrino event separation is not mandatory to cover the physics program of a low energy neutrino factory and thus non-magnetized detectors like water Cerenkov or liquid Argon detectors can be used. We point out, that oscillation itself strongly enhances the signal to noise ratio of a wrong sign muon search, provided there is sufficiently accurate neutrino energy reconstruction. Further, we argue that apart from a magnetic field, other means to distinguish neutrino from anti-neutrino events (at least statistically) can be explored. Combined with the fact that non-magnetic detectors potentially can be made very big, we show that modest neutrino/anti-neutrino separations at the level of 50% to 90% are sufficient to obtain good sensitivity to CP violation and the neutrino mass hierarchy for $\sin^22\theta_{13}>10^{-3}$. These non-magnetized detectors have a rich physics program outside the context of a neutrino factory, including topics like supernova neutrinos and proton decay. Hence, our observation opens the possibility to use a multi-purpose detector also in a neutrino factory beam.Comment: 13 pages, 4 figures, discussion improved, new figure 4, version to appear in PL

Effect of body mass index on the incidence of perineal trauma.

OBJECTIVE: To investigate the association between perineal trauma at childbirth and maternal body mass index (BMI), and estimate the risk of perineal trauma among different BMI groups. METHODS: Data were retrospectively assessed from all vaginal deliveries in a UK tertiary maternity unit between 1999 and 2014. Associations between BMI at booking and first- and second-degree tears (minor perineal trauma), third- and fourth-degree tears (obstetric anal sphincter injuries [OASIS]), and frequency of instrumental deliveries were assessed. Multivariate logistic regression included the factors BMI (weight in kilograms divided by the square of height in meters), age, ethnicity, smoking, parity, pregnancy length, episiotomies, instrumental delivery, and birth weight. RESULTS: Data from 45 557 deliveries were used. Compared with women with a normal BMI (<25), odds of minor perineal trauma were significantly reduced among women with obesity (BMI 30 to <35; odds ratio [OR] 0.91, 95% confidence interval [CI] 0.84-0.99) or severe obesity (BMI ≥35; OR 0.87, 95% CI 0.77-0.98). OASIS was not significantly associated with BMI. Instrumental delivery rates were higher among women with normal BMI (5936/27 107; 22.0%) than among those with severe obesity (284/2032; 14.0%). CONCLUSION: Increased BMI at booking was associated with a reduced incidence of minor perineal trauma at delivery, but was not associated with OASIS

The effect of habitat quality on foraging patterns, provisioning rate and nestling growth in Corsican blue tits Parus caeruleus.

Many bird species face seasonal and spatial variation in the availability of the specific food required to rear chicks. Caterpillar availability is often identified as the most important factor determining chick quality and breeding success in forest birds, such as tits Parus spp. It is assumed that parents play an important role in mediating the effect of environment on chick development. A reduction in prey availability should therefore result in increased foraging effort to maintain the amount of food required for optimal chick development. To investigate the capacity of adults to compensate for a reduction in food supply, we compared the foraging behaviour of Blue Tits Parus caeruleus breeding in rich and poor habitats in Corsica. We monitored the foraging effort of adults using radiotelemetry. We also identified and quantified prey items provided to nestlings by using a video camera mounted on the nest. We found that the mean travelling distance of adults was twice as great in the poor habitat as it was in the rich. Despite the marked difference in foraging distance, the proportion of optimal prey (caterpillars) in the diet of the chicks and the total biomass per hour per chick did not differ between the two habitats. We argue that relationships between habitat richness, offspring quality and breeding success cannot be understood adequately without quantifying parental effort

Evaluation of the LEP Centre-of-Mass Energy Above the W-Pair Production Threshold

Knowledge of the centre-of-mass energy at LEP2 is of primary importance to set the absolute energy scale for the measurement of the W-boson mass. The beam energy above 80 GeV is derived from continuous measurements of the magnetic bending field by 16 NMR probes situated in a number of the LEP dipoles. The relationship between the fields measured by the probes and the beam energy is calibrated against precise measurements of the average beam energy between 41 and 55 GeV made using the resonant depolarisation technique. The linearity of the relationship is tested by comparing the fields measured by the probes with the total bending field measured by a flux loop. This test results in the largest contribution to the systematic uncertainty. Several further corrections are applied to derive the the centre-of-mass energies at each interaction point. In addition the centre-of-mass energy spread is evaluated. The beam energy has been determined with a precision of 25 MeV for the data taken in 1997, corresponding to a relative precision of 2.7x10^{-4}. This is small in comparison to the present uncertainty on the W mass measurement at LEP. However, the ultimate statistical precision on the W mass with the full LEP2 data sample should be around 25 MeV, and a smaller uncertainty on the beam energy is desirable. Prospects for improvements are outlined.Comment: 24 pages, 10 figures, Latex, epsfig; replaced by version accepted by European Physical Journal

Nonexotic Neutral Gauge Bosons

We study theoretical and experimental constraints on electroweak theories including a new color-singlet and electrically-neutral gauge boson. We first note that the electric charges of the observed fermions imply that any such Z' boson may be described by a gauge theory in which the Abelian gauge groups are the usual hypercharge along with another U(1) component in a kinetic-diagonal basis. Assuming that the observed quarks and leptons have generation-independent U(1) charges, and that no new fermions couple to the standard model gauge bosons, we find that their U(1) charges form a two-parameter family consistent with anomaly cancellation and viable fermion masses, provided there are at least three right-handed neutrinos. We then derive bounds on the Z' mass and couplings imposed by direct production and Z-pole measurements. For generic charge assignments and a gauge coupling of electromagnetic strength, the strongest lower bound on the Z' mass comes from Z-pole measurements, and is of order 1 TeV. If the new U(1) charges are proportional to B-L, however, there is no tree-level mixing between the Z and Z', and the best bounds come from the absence of direct production at LEPII and the Tevatron. If the U(1) gauge coupling is one or two orders of magnitude below the electromagnetic one, these bounds are satisfied for most values of the Z' mass.Comment: 26 pages, 2 figures. A comparison with the LEP bounds on sneutrino resonances is include