Fertility in Austria: Past, Present and the Near Future

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Bis(2,2′-bipyridyl-κ2 N,N′)bis­(2-hydroxy­benzoato)-κO 1;κ2 O 1,O 1′-cadmium(II) methanol solvate

The title compound, [Cd(C7H5O3)2(C10H8N2)2]·CH3OH, contains one monomeric seven-coordinate cadmium complex and one methanol solvate mol­ecule. The CdII atom is coordinated to two 2,2′-bipyridyl ligands via the N atoms and to two salicylate anions (Hsal−) via the carboxyl­ate O atoms, which act as monodentate ligand for the one and bidentate ligand for the second. The CdII atom exhibits a {6 + 1} environment, approximately described as a distorted capped octa­hedron with the apical positions occupied by one of the two N atoms belonging to one bipyridyl ligand and one of the two carboxyl­ate O atoms from the monodentate Hsal− ligand. Two intra­molecular six-membered hydrogen-bonded rings are present, generated from inter­actions between the carboxyl­ate and hydr­oxy groups of the salicylate ligands. There is one inter­molecular hydrogen-bonding inter­action involving the methanol solvent mol­ecule and the carboxyl­ate group from the monodentate Hsal− ligand. The crystal packing is governed by π–π stacking inter­actions [centroid–centroid distance = 3.783 (4) Å] which occur between bipyridyl ligands, by C—H⋯O and C—H⋯π inter­actions and by numerous van der Waals contacts

A way to model stochastic perturbations in population dynamics models with bounded realizations

International audienceIn this paper, we analyze the use of the Ornstein-Uhlenbeck process to model dynamical systems subjected to bounded noisy perturbations. In order to discuss the main characteristics of this new approach we consider some basic models in population dynamics such as the logistic equations and competitive Lotka-Volterra systems. The key is the fact that these perturbations can be ensured to keep inside some interval that can be previously fixed, for instance, by practitioners, even though the resulting model does not generate a random dynamical system. However, one can still analyze the forwards asymptotic behavior of these random differential systems. Moreover, to illustrate the advantages of this type of modeling, we exhibit an example testing the theoretical results with real data, and consequently one can see this method as a realistic one, which can be very useful and helpful for scientists

Analysis of roll gap heat transfers in hot steel strip rolling through roll temperature sensors and heat transfer models

International audienceThis paper presents an analysis of roll bite heat transfers during pilot hot steel strip rolling. Two types of temperature sensors (drilled and slot sensors) implemented near roll surface are used with heat transfer models to identify interfacial heat flux, roll surface temperature and Heat Transfer Coefficient HTCroll-bite in the roll bite. It is shown that: - the slot type sensor is more efficient than the drilled type sensor to capture correctly fast roll temperature changes and heat fluxes in the bite during hot rolling but its life's duration is shorter. - average HTCroll-bite is within the range 15-26 kW/m2/K: the higher the strip reduction (e.g. contact pressure) is, the higher the HTCroll-bite is. - scale thickness at strip surface tends to decrease heat transfers in the bite from strip to roll. - HTCroll-bite is not uniform along the roll-strip contact but seems proportional to contact pressure. - this non uniform HTCroll-bite along the contact could contribute to decrease thermal shock (so roll thermal fatigue) when the work roll enters the roll bite, in comparison to a uniform HTCroll-bite. - Heat transfer in the roll bite is mainly controlled by heat conduction due to the huge roll-strip temperature difference, whil

Experimental study of interfacial heat flux and surface temperature by inverse analysis with thermocouple (fully embedded) during hot steel strip rolling

International audienceKnowledge of temperature distribution in the roll is fundamental aspect in cold rolling. An inverse analytical method has been previously developed to determine interfacial heat flux and surface temperature by measuring the temperature with a thermocouple (fully embedded) at only one point inside the roll. On this basis some pilot mill tests have been performed. The temperature sensor, the calibration procedure and rolling tests at different strip rolling conditions (5%, 10%, 15% and 20%) are described. Results show a good agreement with well-known theoretical models. Moreover the CPU times of the method (around 0.05 s by cycle) enable an online control of the rolling process

Expression, purification, crystallization and preliminary X-ray analysis of the cathelicidin motif of the protegrin-3 precursor

International audienc

Electronic support tools for identification and management of rice weeds in Africa for better-informed agricultural change agents

International audienceWe developed an interactive electronic weed identification tool, AFROweeds, and an online network, Weedsbook, for agricultural change agents to aid communication and offer assistance to rice farmers with specific weed problems. We collected quantitative and qualitative data to assess effectiveness and usefulness of these products with potential users. With the online version of AFROweeds, used on an electronic tablet, average weed identification time in the field was 7 min 6 s with 44% successful identifications. Poor mobile network coverage and slow internet were the main reasons for the relative long identification time and low success rate. A second trial was done with the offline version, pre-installed on a tablet. The average identification time was 6 min 34 s, with a success rate of 75%. The online network Weedsbook, established alongside AFROweeds, was assessed by the test users as a useful additional aid, enabling agricultural change agents and agronomists to exchange information or request assistance on all aspects of weeds and weed management. The potential improvements of both products are discussed

Peripheral skin cooling during hyper-gravity: hemodynamic reactions

Introduction: Orthostatic dysregulation occurs during exposure to an increased gravitational vector and is especially common upon re-entering standard Earth gravity (1 g) after an extended period in microgravity (0 g). External peripheral skin cooling (PSC) has recently been described as a potent countermeasure against orthostatic dysregulation during heat stress and in lower body negative pressure (LBNP) studies. We therefore hypothesized that PSC may also be an effective countermeasure during hyper-gravity exposure (+Gz). Methods: To investigate this, we designed a randomized short-arm human centrifuge (SAHC) experiment (“Coolspin”) to investigate whether PSC could act as a stabilizing factor in cardiovascular function during +Gz. Artificial gravity between +1 g and +4 g was generated by a SAHC. 18 healthy male volunteers completed two runs in the SAHC. PSC was applied during one of the two runs and the other run was conducted without cooling. Each run consisted of a 10-min baseline trial followed by a +Gz step protocol marked by increasing g-forces, with each step being 3 min long. The following parameters were measured: blood pressure (BP), heart rate (HR), stroke volume (SV), total peripheral resistance (TPR), cardiac output (CO). Furthermore, a cumulative stress index for each subject was calculated. Results: +Gz led to significant changes in primary as well as in secondary outcome parameters such as HR, SV, TPR, CO, and BP. However, none of the primary outcome parameters (HR, cumulative stress-index, BP) nor secondary outcome parameters (SV, TPR, CO) showed any significant differences—whether the subject was cooled or not cooled. Systolic BP did, however, tend to be higher amongst the PSC group. Conclusion: In conclusion, PSC during +Gz did not confer any significant impact on hemodynamic activity or orthostatic stability during +Gz. This may be due to lower PSC responsiveness of the test subjects, or an insufficient level of body surface area used for cooling. Further investigations are warranted in order to comprehensively pinpoint the exact degree of PSC needed to serve as a useful countermeasure system during +Gz

Evaluación genotóxica de las moléculas con efectos tripanocida y leishmanicida cantin-6-ona y 5-metoxicantin-6-ona en células de médula ósea de ratones

La tripanosomiasis americana y la leishmaniasis son problemas de salud pública relevantes en Iberoamérica. Las drogas utilizadas actualmente para el tratamiento de estas enfermedades poseen efectos colaterales tóxicos severos. Varios grupos de investigación están abocados a la búsqueda de productos naturales y sintéticos para encontrar nuevos agentes terapéuticos efectivos que no presenten reacciones colaterales adversas. En la evaluación de compuestos de la especie vegetal Zanthoxylum chiloperone (Rutaceae), se demostró que compuestos aislados del extracto presentaban actividad leishmanicida, tripanocida y antifúngica in vivo. Teniendo como antecedentes estos resultados, en el presente estudio se evaluaron los efectos genotóxico y citotóxico del cantín-6-ona y del 5-metoxicantin-6-ona, moléculas aisladas de la planta, en células de médula ósea de animales tratados. El estudio de los efectos genotóxicos se hizo a través del ensayo de modificaciones en la frecuencia de micronúcleos y el efecto citotóxico por modificaciones en la relación entre eritrocitos policromáticos y eritrocitos normocromáticos. Se realizaron 2 ensayos independientes y en cada ensayo los animales fueron divididos en tres grupos de tratamiento: GRUPO I: control negativo que recibió 200 uL de agua y 2.1% de DMSO, vía oral, GRUPO II: compuesto a ser evaluado (canthin-6-ona o 5-methoxicantin-6-ona) con 2.1% de DMSO, y GRUPO III: control positivo que recibió ciclofosfamida 50mg/kg/peso del animal, vía intraperitoneal. El análisis estadístico mostró que ambos compuestos no presentaron efectos genotóxicos ni citotóxicos. Estos resultados permiten proponer a estas moléculas como candidatas a ser sometidas a estudios más detallados como potenciales fármacos contra estas dos enfermedades