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Two analogous tetranuclear lanthanide complexes have been synthesized with the general formula [Ln4(vht)4(MeOH)8](NO3)4·aMeOH·bH2O, where H2vht = (3,6-bis(vanillidenehydrazinyl)-1,2,4,5-tetrazine) and Ln = DyIII (1), GdIII (2). These complexes are characterized by several techniques; including single-crystal X-ray diffraction, SQUID magnetometry and single-crystal micro-SQUID hysteresis loop measurements. Elucidation of the crystal structure of the complexes shows that the lanthanide ions are bridged by a tetrazine ring, a rare bridging moiety for lanthanide ions. Magnetic studies reveal that both 1 and 2 exhibit weak ferromagnetic exchange interactions between Ln ions, and 1 displaying Single-Molecule Magnet (SMM) behaviour with a magnetisation reversal barrier of Ueff = 158 K (τ0 = 1.06 × 10−7 s). [ABSTRACT FROM AUTHOR]

A family of three dinuclear dysprosium complexes have been successfully synthesized and studied in terms of their magnetic properties. Complexes 1 and 2 share the formula [Dy2(ovph)2Cl2(solvent)2], where H2ovph = pyridine-2-carboxylic acid [(2-hydroxy-3-methoxyphenyl)methylene] hydrazide, and solvent = DMF (1), i-PrOH (2), while complex 3, [Dy2(ovph)2Cl2(H2O)3(EtOH)], exhibits differences in terms of the identity and number of coordinated solvent molecules. Thus, we investigate the impact of terminally bonded solvent molecules on the slow relaxation dynamics of {Dy2} SMMs, a parameter which can sometimes be overlooked in the quest to attain higher energy barriers. Notably, the exchange of DMF for i-PrOH, both of which coordinate through a single oxygen atom, results in a near 2-fold increase in Ueff, from 58 to 98 K, for 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Systematic verifications of patient''s specific intensity-modulated radiation treatments are usually performed with absolute and relative measurements. The results constitute a database which allows the identification of potential systematic errors. Material and methods: We analyzed 1270 beams distributed in 232 treatment plans. Step-and-shoot intensity-modulated radiation treatments were performed with a Clinac (6 and 23 MV) and sliding window intensity-modulated radiation treatments with a Novalis (6 MV). Results: The distributions obtained do not show systematic error and all the control meet specified tolerances. Conclusion: These results allow us to reduce controls specific patients for treatments performed under identical conditions (location, optimization and segmentation parameters of treatment planning system, etc.). [Copyright &y& Elsevier]

A novel statistical technique called space--time empirical normal mode (ST-ENM) is applied in a diagnostic study of the genesis of a secondary eyewall in a simulated hurricane using the nonhydrostatic, high-resolution fifth-generation Pennsylvania State University (PSU)--National Center for Atmospheric Research (NCAR) Mesoscale Model (MM5). The bases obtained from the ST-ENM technique are nonstationary, dynamically relevant, and orthogonal in the sense of wave activity. The wave activity spectra of the wavenumber-1 anomalies show that the leading modes (1--6) exhibit mainly characteristics of vortex Rossby waves (VRWs). These modes together explain about 75%% of the total wavenumber-1 variance in a period of 24 h. Analysis of the Eliassen--Palm (EP) flux and its time-mean divergence corresponding to the total contribution from these modes indicated that in the lower troposphere VRWs not only propagate inward (outward) in the primary eyewall region where the radial gradient of the basic-state potential vorticity is large and positive (large and negative), but there is also wave activity propagating outside the primary eyewall. Consequently, maximum cyclonic eddy angular momentum is transported not only inside the radius of maximum wind (RMW) by VRWs in the primary eyewall region, but also close to the location where the secondary eyewall forms by VRWs propagating outside the inner eyewall. The fact that the critical radius for some of the ST-ENMs is contained inside the region where the secondary eyewall forms and the existence of a signal of maximum eddy cyclonic angular momentum flux propagating outward up to the critical radius suggests that a wave--mean flow interaction mechanism and redistribution of angular momentum may be suitable to explain important dynamical aspects of concentric eyewall genesis. [ABSTRACT FROM AUTHOR]

Despite the fact that asymmetries in hurricanes, such as spiral rainbands, polygonal eyewalls, and mesovortices, have long been observed in radar and satellite imagery, many aspects of their origin, space--time structure, and dynamics still remain unsolved, particularly their role on the vortex intensification. The underlying inner-core dynamics need to be better understood to improve the science of hurricane intensity forecasting. To fill this gap, a simple 2D barotropic ''dry'' model is used to perform two experiments starting respectively with a monopole and a ring of enhanced vorticity to mimic hurricane-like vortices during incipient and mature stages of development. The empirical normal mode (ENM) technique, together with the Eliassen--Palm (EP) flux calculations, are used to isolate wave modes from the model datasets to investigate their space--time structure, kinematics, and the impact on the changes in the structure and intensity of the simulated hurricane-like vortices. From the ENM diagnostics, it is shown in the first experiment how an incipient storm described by a vortex monopole intensifies by ''inviscid damping'' of a ''discrete-like'' vortex Rossby wave (VRW) or quasi mode. The critical radius, the structure, and the propagating properties of the quasi mode are found to be consistent with predictions of the linear eigenmode analysis of small perturbations. In the second experiment, the fastest growing wavenumber-4 unstable VRW modes of a vortex ring reminiscent of a mature hurricane are extracted, and their relation with the polygonal eyewalls, mesovortices, and the asymmetric eyewall contraction are established in consistency with results previously obtained from other authors. [ABSTRACT FROM AUTHOR]

Despite the fact that asymmetries in hurricanes (e.g., spiral rainbands, polygonal eyewalls, and mesovortices) have long been observed in radar and satellite imagery, many aspects of their dynamics remain unsolved, particularly in the formation of the secondary eyewall. The underlying associated dynamical processes need to be better understood to advance the science of hurricane intensity forecasting. To fill this gap, a simple 2D barotropic 'dry' model is used to simulate a hurricane-like concentric rings vortex. The empirical normal mode (ENM) technique, together with Eliassen-Palm (EP) flux calculations, are used to isolate wave modes from the model datasets to investigate their impact on the changes in the structure and intensity of the simulated hurricane-like vortex. From the ENM diagnostics, it is shown that asymmetric disturbances outside a strong vortex ring with a large vorticity skirt may relax to form concentric rings of enhanced vorticity that contain a secondary wind maximum. The fact that the critical radius for some of the leading modes is close to the location where the secondary ring of enhanced vorticity develops suggests that a wave-mean flow interaction mechanism based on vortex Rossby wave (VRW) dynamics may explain important dynamical aspects of concentric eyewall genesis (CEG). [ABSTRACT FROM AUTHOR]

Presents an analysis of the nonlinear reflection of an isolated Rossby wave train at a low-latitude. What arguments for nonlinear reflection are based on; Results of numerical experiments in single-layer shallow-water.

Presents numerical solutions of the nonlinear long-time asymptotic form of the equations for disturbances to a parabolic jet. Derivation of the governing equations; Numerical scheme for nonlinear integration; Solutions for steadily propagating disturbances.

Heterozygous 4.1(−) hereditary elliptocytosis results from the absence of one haploid set of protein 4.1, a major component of the red cell skeleton. Two successive epidemiological investigations revealed fifteen probands in the French Northern Alps. The frequency of this disease seems to be very high in four small villages isolated in the Aravis mountains. The genealogical study shows that eleven probands share common ancestors who lived eight or ten generations ago in these villages. Thus there was probably a founder effect from one pair of ancestors, strengthened by endogamy. In contrast, four probands originate from another area and are not genealogically related. Recent results in molecular genetics support the present data. [ABSTRACT FROM PUBLISHER]

Tropical Cyclone (TC) formation regions are analysed in twelve CMIP5 models using a recently developed diagnostic that provides a model-performance summary in a single image for the mid-summer TC season. A subjective assessment provides an indication of how well the models perform in each TC basin throughout the globe, and which basins can be used to determine possible changes in TC formation regions in a warmer climate. The analysis is necessarily succinct so that seven basins in twelve models can be examined. Consequently, basin performance was reduced to an assessment of two common problems specific to each basin. Basins that were not too adversely affected were included in the projection exercise. The North Indian basin was excluded because the mid-summer analysis period covers a lull in TC activity. Surprisingly, the North Atlantic basin also had to be excluded, because all twelve models failed the performance assessment. A slight poleward expansion in the western North Pacific and an expansion towards the Hawaiian Islands in the eastern North Pacific is plausible in the future, while a contraction in the TC formation regions in the eastern South Indian and western South Pacific basins would reduce the Australian region TC formation area. More than half the models were too active in the eastern South Pacific and South Atlantic basins. However, projections based on the remaining models suggest these basins will remain hostile for TC formation in the future. These southern hemisphere changes are consistent with existing projections of fewer southern hemisphere TCs in a future warming world [ABSTRACT FROM AUTHOR]

The cause of pain in Achilles tendinopathy is thought to be related to the presence of neovascularization in the tendon as seen on color Doppler ultrasound. Asymptomatic pathology has been observed in patellar tendons of elite athletes. The purpose of this study was to examine the prevalence of Achilles tendon pain and the characteristics of Achilles tendons in a young athletic population. Sixty-four varsity athletes underwent color Doppler ultrasound imaging to determine tendon thickness, presence of degeneration and neovascularization. The presence of swelling and tenderness was determined, and Achilles tendon pain was rated on three visual analogue scales (VAS) (pain during exercise, pain at rest, pain during daily activities) as well as on the VISA-A scale. Tendon symptoms were not related to the presence of neovascularization. There was a low prevalence of Achilles tendinopathy, tenderness, and neovascularization in this population. Neovascularization was seen in both a painful and a non-painful tendon. [ABSTRACT FROM AUTHOR]

This study uses sets of historical family reconstitutions from all of Quebec and from four villages of the Haut-Jura, France--first marriages of 2226 and 994 women, respectively--to investigate the physiological and social factors affecting age of mother at last birth before and during fertility transition. Age remained high throughout the period covered in Quebec, under 'natural' conditions, but showed a steady decline in the French material which extends to late 19th century generations practising family limitation. Age at marriage had no influence in Quebec; in France, however, women with the most surviving children at age 35 continued childbearing the latest. There was no link between biological ability to achieve a live birth, or in health status or aging rhythm, and age at last birth. Behaviour of mothers and daughters showed no relation. The variability in age at last birth thus appears to be random under natural conditions; with the onset of controls, social differences seem to influence not only the end of childbearing, but all aspects of behaviour governing final family size and child survival. [ABSTRACT FROM AUTHOR]

EON-ROSE (Earth-System Observing Network - Réseau d'Observation du Système terrestrE) is a new initiative for a pan-Canadian research collaboration to holistically examine Earth systems from the ionosphere into the core. The Canadian Cordillera Array (CC Array) is the pilot phase, and will extend across the Cordillera from the Beaufort Sea to the U.S. border. The vision for EON-ROSE is to install a network of telemetered observatories to monitor solid Earth, environmental and atmospheric processes. EON-ROSE is an inclusive, combined effort of Canadian universities, federal, provincial and territorial government agencies, industry, and international collaborators. Brainstorming sessions and several workshops have been held since May 2016. The first station will be installed at Kluane Lake Research Station in southwestern Yukon during the summer of 2018. The purpose of this report is to provide a framework for continued discussion and development. [ABSTRACT FROM AUTHOR]

The article discusses the Observing System Research and Predictability Experiment (THORPEX), a global research program built to improve the accuracy of high-impact weather predictions, and mentions the science of prediction. Topics include various subprograms of the THORPEX Science Plan, like predictability and dynamical processes (PDP), the development of an interactive forecast system, and aspects of high-impact weather systems.

Résumé Introduction La maltraitance des enfants constitue une problématique complexe qui nécessite une approche pluridisciplinaire encore non systématique en France. Le centre d’accueil en urgence des victimes d’agression (CAUVA) du centre hospitalier universitaire (CHU) de Bordeaux a pu rassembler dès création différents acteurs médicaux, paramédicaux et sociaux. Il a ainsi été établi une procédure d’évaluation psychosociale standardisée, qui est systématiquement diligentée en cas de suspicion de maltraitance sur mineurs. Méthode Nous avons étudié les 74 dossiers non judiciarisés de sujets mineurs (45 filles) ayant bénéficié d’une évaluation pour suspicion de violences entre le 1 er juillet 2014 et le 30 juin 2015. Résultats Ils étaient âgés en moyenne de 7 ans, nous avaient été adressés par des partenaires internes ( n = 15) ou externes au CHU ( n = 37), 22 s’étant présentés spontanément et alléguaient principalement (75 %) des faits de violences sexuelles. Trente-cinq ont pu rentrer au domicile, 17 fait l’objet d’un dépôt de plainte, 19 d’un signalement au Procureur de la République et 3 d’une information préoccupante au Conseil départemental. Conclusion En l’absence de consensus national sur la méthodologie d’évaluation des cas de suspicion de violences sur mineur, nous proposons une évaluation psychosociale comportant un regard collégial qui permet non seulement de faciliter le travail des professionnels mais également le dépistage et la judiciarisation des cas de maltraitance. Summary Introduction Maltreatment is a complex issue and therefore, requires a multidisciplinary approach, which has been commonly used in North America since the 1980s but remains unsystematic in France. Since 1999, the Centre d’Accueil en Urgence des Victimes d’Agression (emergency unit for victims of assault) of the Bordeaux University Hospital has brought together various medical, paramedical, and social actors on this issue. A standardized psychosocial assessment procedure has been introduced and is detailed in this paper, and was consistently conducted in all cases of suspicion of abuse on a minor. Method The authors studied 74 cases of minors having undergone a psychosocial assessment following suspicions of maltreatment between 1 July 2014 and 30 June 2015 that were not referred to the courts. Results Forty-five girls and 29 boys, mean age 7 years, claiming mainly (75 %) to have been subjected to sexual violence, were addressed to us by internal partners ( n = 15) and external partners ( n = 37) and 22 who came to our unit by self-referral. Following our assessment, 35 returned to their home and 36 went to court following a police complaint ( n = 17) and a report filed to the public prosecutor of the Republic ( n = 19). Three of these cases were subjected to a report on matters of concern sent to the departmental council. Conclusion Given the absence of a national consensus on the methodology used for assessing suspicions of maltreatment on minors, our psychosocial assessment can facilitate the task with its peer review as well as the detection and judicialization of the maltreatment. The authors also highlight the recent modification of article 226-14 of the Penal Code, which aims at protecting professionals reporting matters to legal authorities from any legal proceeding, except if it is established that the individual did not act in good faith. [ABSTRACT FROM AUTHOR]

Marriage-first birth intervals are examined in two historical populations, Quebec (1608-1765) and Haut-Jura (1689-1980), comparing intervals in mothers and daughters, and in sister-sister pairs. The results point to a weak relationship between intervals of mothers and daughters, though it does not attain significance. Shared environment does not seem to be responsible since there is no association between pairs of sisters from the same populations. [ABSTRACT FROM AUTHOR]

Purpose: The use of small photon fields is now an established practice in stereotactic radiosurgery and radiotherapy. However, due to a lack of lateral electron equilibrium and high dose gradients, it is difficult to accurately measure the dosimetric quantities required for the commissioning of such systems. Moreover, there is still no metrological dosimetric reference for this kind of beam today. In this context, the first objective of this work was to determine and to compare small fields output factors (OF) measured with different types of active detectors and passive dosimeters for three types of facilities: a CyberKnife® system, a dedicated medical linear accelerator (Novalis) equipped with m3 microMLC and circular cones, and an adaptive medical linear accelerator (Clinac 2100) equipped with an additional m3 microMLC. The second one was to determine the kQclin,Qmsrfclin,fmsr correction factors introduced in a recently proposed small field dosimetry formalism for different active detectors. Methods: Small field sizes were defined either by microMLC down to 6 × 6 mm2 or by circular cones down to 4 mm in diameter. OF measurements were performed with several commercially available active detectors dedicated to measurements in small fields (high resolution diodes: IBA SFD, Sun Nuclear EDGE, PTW 60016, PTW 60017; ionizing chambers: PTW 31014 PinPoint chamber, PTW 31018 microLion liquid chamber, and PTW 60003 natural diamond). Two types of passive dosimeters were used: LiF microcubes and EBT2 radiochromic films. Results: Significant differences between the results obtained by several dosimetric systems were observed, particularly for the smallest field size for which the difference in the measured OF reaches more than 20%. For passive dosimeters, an excellent agreement was observed (better than 2%) between EBT2 and LiF microcubes for all OF measurements. Moreover, it has been shown that these passive dosimeters do not require correction factors and can then be used as reference dosimeters. Correction factors for the active detectors have then been determined from the mean experimental OF measured by the passive dosimeters. Conclusions: Four sets of correction factors needed to apply the new small field dosimetry formalism are provided for several active detectors. A protocol for small photon beams OF determination based on passive dosimeters measurements has been recently proposed to French radiotherapy treatment centers. [ABSTRACT FROM AUTHOR]