Crystal structure of methyl N-ferrocenylcarbamate

The asymmetric unit of the title compound, [Fe(C5H5)(C7H8NO2)], contains two independent molecules consisting of a ferrocenyl moiety and a nitrogen-bound methyl carbamate. These units are almost perpendicular to each other, making dihedral angles of 87.74 (9) and 87.32 (8)°. In each independent molecule, the cyclopentadienyl rings deviate slightly from an eclipsed conformation and lie virtually parallel [dihedral angles = 1.42 (15) and 0.49 (13)°]. In the crystal, molecules are linked by N—H...O hydrogen bonds into chains along the a-axis direction

Déterminisme de la feuillaison de Acacia tortilis (Forsk.) dans la réserve sylvopastorale de Sogobé, Ferlo, Nord-Sénégal

Ce travail présente l’étude de la phénologie foliaire de Acacia tortilis dans la réserve sylvopastorale de Sogobé (16° 20’N et 15° 25’ W) au  Nord-Sénégal. Le suivi a porté sur les paramètres climatiques et les différents stades de la feuillaison. Les données du suivi phénologique ont été soumises à une analyse en composantes principales. Les  précipitations de la pleine saison des pluies (août, septembre) sont supérieures à l’évapotranspiration potentielle (ETP) de 35% alors que le déficit de saturation de l’air plus élevé en période sèche est consécutif à une ETP plus importante en 2000. En outre, les réserves hydriques du sol ont été plus importantes en 1999 qu’en 2000 à l’exception du mois de septembre. Trois grands événements caractérisent le cycle de la feuille de Acacia tortilis. Le débourrement foliaire, qui dure 2 à 4 mois, présente deux vagues de bourgeons dont le maintien de la première vague dépend de la précocité des précipitations alors que la vitesse d’épanouissement de la seconde vague est fonction de l’abondance et de la régularité des   pluies. La croissance et maturité s’étalent sur 7 mois. La sénescence  foliaire qui s’installe lorsque la réserve hydrique du sol est inférieure à 20%, est soit précoce (janvier, février) soit tardive (mars, avril). A fin de mieux caractériser la disponibilité du fourrage vert de cette espèce dans cette sylvopastorale, il s’avère opportun d’évaluer la variabilité de la production de biomasse foliaire.© 2013 International Formulae Group. All rights reserved.Mots clés : Déterminisme, phénologie foliaire, Acacia tortilis, Ferlo,  Nord-Sénégal

Lamb dip of a Quadrupole Transition in H2_2

The saturated absorption spectrum of the hyperfine-less S(0) quadrupole line in the (2-0) band of H$_2$ is measured at $\lambda=1189$ nm, using the NICE-OHMS technique under cryogenic conditions (72~K). It is for the first time that a Lamb dip of a molecular quadrupole transition is recorded. At low (150-200 W) saturation powers a single narrow Lamb dip is observed, ruling out an underlying recoil doublet of 140 kHz. Studies of Doppler-detuned resonances show that the red-shifted recoil component can be made visible for low pressures and powers, and prove that the narrow Lamb dip must be interpreted as the blue recoil component. A transition frequency of 252\,016\,361\,164\,(8) kHz is extracted, which is off by -2.6 (1.6) MHz from molecular quantum electrodynamical calculations therewith providing a challenge to theory.Comment: 4 pages, 5 figure

Variations topographiques de la fructification d’une espèce ligneuse fourragère, Acacia tortilis (Forsk.) au Ferlo, Nord-Sénégal

La production annuelle de gousses de Acacia tortilis, a été suivie sur une toposéquence de 1,8% de dénivellation dans la réserve sylvo-pastorale de Sogobé au Nord-Sénégal. Les observations sont effectuées tous les quinze jours en saison des pluies et une fois par mois en saison sèche. Les suivis simultanés de la fructification de cette espèce en rapport avec l’évolution de l’eau du sol et des variables climatiques vise à caractériser l’effet de la topographie sur la production de gousses par unité de croissance. Les données sont soumises à une analyse multidimensionnelle et à une analyse de variance. La fructification de l’espèce intervient de novembre à juin. L’ACP effectuée à partir des relevés mensuels et des stades de fructification a permis d’identifier trois variables de la fructification : la nouaison des gousses, leur croissance et leur maturité et enfin leur dissémination. Cette dissémination peut être partielle (février et avril) ou totale (avril et juin). La nouaison des gousses concerne les mois de novembre et décembre (saison post-pluvieuse) alors que leur croissance et leur maturité se font de novembre à février (saison sèche fraîche). La dissémination des gousses de cette espèce et leur exploitation pour l’alimentation du bétail seraient à l’origine de la réduction de la densitédes fruits entre janvier et mai qui coïncide avec l’absence du tapis herbacée. Cependant, la biomasse des gousses par unité de croissance est significativement plus élevée chez les arbres de bas-fond qui bénéficient d’une alimentation hydrique plus favorable.Mots clés: Variabilité topographique, production de gousses, fourrage, Acacia tortilis, sahel, Zone sylvopastorale, Nord-Sénégal

Phase 1 Anglo-French report on the IMPRESS Health 2 (Interreg IVA Channel Programme) project 4282: understanding factors behind the late testing and diagnosis of HIV

This report outlines the combined Anglo-French findings and analysis of data from the phase 1 (research) phase of the Interreg IVA Channel Programme funded IMPRESS Health 2 project examining factors behind the late testing and diagnosis of HIV in Kent, Medway, and Picardy (France)

Understanding factors behind the late testing and diagnosis of HIV: Findings from phase 1 of the IMPRESS Health 2 (Interreg IVA Channel Programme) Project

Over 100,000 have HIV in the UK. However, while effective treatment exists, there is neither a cure nor a preventive vaccine, so 500+ people die from AIDS every year with many others dying undiagnosed. Health policy focuses on prevention and support, but it is necessary to increase the number of early diagnoses and reduce the rate of spread (Public Health England, 2014). Approximately 25% of HIV positive individuals do not know their status however, and almost half of all UK diagnoses occur late. It is vital therefore, to understand and address barriers to early testing and diagnoses to address this trend. Clinical data for 240 patients diagnosed with HIV in 3 trusts in Kent and Medway over 5 years were analysed in relation to clinical, social, demographic and psychosexual factors likely to affect knowledge of HIV and their decision to seek a test. Fifty-three semi-structured interviews were also conducted with patients and healthcare professionals to elicit experienced and perceptions about barriers to testing and ways to increase uptake. Patients were aged 19-81 (mean 40 years) and 67.5% were men. Women were more likely to be diagnosed late however (67.9% versus 56.8%), and late diagnosis was higher than the national average for both sexes (60.4%) with the highest rates in Medway (66.1%) and Maidstone and Tunbridge Wells (64.6%). Patients diagnosed late were 4 years older than those diagnosed early, and late diagnosis was higher in ethnic minority groups (70.2%) compared to white British (53.0%). Those born outside the UK were also generally diagnosed later (69.8%). The most frequent categories affected were heterosexuals (56.2%), men who have sex with men (36.6%) and intravenous drug users (2.0%). Patients diagnosed during an acute hospital admission were far more likely to be diagnosed late (89.1%) compared to other settings (49.6% - 57.1%). Qualitative data suggested that outmoded notions of HIV as a ‘gay’ disease still prevailed and heterosexuals did not generally consider themselves to be at risk. Healthcare professionals sometimes failed to acknowledge risks in ‘non-traditional’ groups and often overlooked HIV as a likely cause of symptoms until they were seriously unwell. Clearer public health messages should be targeted at the general population and there is a need to better educate healthcare professionals, especially GPs about the clinical indicators of HIV which also needs to be de-stigmatised

Lamb-peak spectrum of the HD (2-0) P(1) line

A saturation spectroscopy measurement of the P(1) line of the ($2-0$) band in HD is performed in a sensitive cavity-enhanced optical setup involving frequency comb calibration. The spectral signature is that of a Lamb-peak, in agreement with a density-matrix model description involving 9 hyperfine components and 16 crossover resonances of $\Lambda$-type. Comparison of the experimental spectra with the simulations yields a rovibrational transition frequency at 209,784,242,007 (20) kHz. Agreement is found with a first principles calculation in the framework of non-adiabatic quantum electrodynamics within 2$\sigma$, where the combined uncertainty is fully determined by theory

Funiculars anomalies during childbirth: about 562 cases collected in Pikine National Hospital

Background: Establish an epidemiological description of the different types of umbilical cord anomalies in our reference structure and to assess their impact on the prognosis of childbirth.Methods: We conducted a descriptive study, cross over a period of one year in Obstetrics and Gynecology Service Level III of Pikine Hospital. We included all women in labor have reached the term less than 28 weeks gestation and delivering a newborn with umbilical cord abnormality diagnosed during labor or during the expulsion.Results: During this period, we compiled 562 anomalies of the umbilical cord, which gave a frequency of 23.8%. Length discrepancies were far the most frequent (67.4%). Only the prolapsed cord was an independent risk factor for cesarean section (p = 0.036). The rate of episiotomy and tear was significantly higher in case of brevity (primitive or induced) cord (p = 0.042). Apgar score ≤7 was significantly related to the presence of brevity (p = 0.000), excessive length (p = 0.048) or cord prolapse (p = 0.037).Conclusions: This study has allowed us to see that the funicular abnormalities impede the smooth running of childbirth. Their occurrence is facilitated by the excess amniotic fluid, prematurity and low birth weight. Their research during prenatal ultrasounds should be systematic

A hybrid optical-wireless network for decimetre-level terrestrial positioning

Global navigation satellite systems (GNSS) are widely used for navigation and time distribution, features indispensable for critical infrastructure such as mobile communication networks, as well as emerging technologies like automated driving and sustainable energy grids. While GNSS can provide centimetre-level precision, GNSS receivers are prone to many-metre errors due to multipath propagation and obstructed view of the sky, which occur especially in urban areas where accurate positioning is needed most. Moreover, the vulnerabilities of GNSS, combined with the lack of a back-up system, pose a severe risk to GNSS-dependent technologies. Here, we demonstrate a terrestrial positioning system which is independent of GNSS and offers superior performance through a constellation of radio transmitters, connected and time-synchronised at the sub-nanosecond level through a fibre-optic Ethernet network. Employing optical and wireless transmission schemes similar to those encountered in mobile communication networks, and exploiting spectrally efficient virtual wideband signals, the detrimental effects of multipath propagation are mitigated, thus enabling robust decimetre-level positioning and sub-nanosecond timing in a multipath-prone outdoor environment. This work provides a glimpse of a future in which telecommunication networks provide not only connectivity, but also GNSS-independent timing and positioning services with unprecedented accuracy and reliability.Comment: 38 pages, 9 figures, 3 table