Tectonic setting of the kenya rift in the nakuru area, based on geophysical prospecting

In this paper, we present results of tectonic and geophysical investigations in the Kenya Rift valley, in the Nakuru area. We compiled a detailed geological map of the area based on published earlier works, well data and satellite imagery. The map was then integrated with original fieldwork and cross sections were constructed. In key areas, we then performed geophysical survey using Electrical Resistivity Tomography (ERT), Hybrid Source AudioMagnetoTelluric (HSAMT), and single station passive seismic measurements (HVSR). In the study area, a volcano-sedimentary succession of the Neogene-Quaternary age characterized by basalts, trachytes, pyroclastic rocks, and tephra with intercalated lacustrine and fluvial deposits crops out. Faulting linked with rift development is evident and occurs throughout the area crosscutting all rock units. We show a rotation of the extension in this portion of the Kenya rift with the NE-SW extension direction of a Neogene-Middle Pleistocene age, followed by the E-Wextension direction of anUpper Pleistocene-Present age. Geophysical investigations allowed to outline main lithostratigraphic units and tectonic features at depth and were also useful to infer main cataclasites and fractured rock bodies, the primary paths for water flow in rocks. These investigations are integrated in a larger EU H2020 Programme aimed to produce a geological and hydrogeological model of the area to develop a sustainable water management system

Effect of Thiamine Pyrophosphate (Bicarbossilasi®) Administration on the Exercising Horse Metabolism

Thiamine pyrophosphate (TPP) is the phosphorylated and active form of thiamine (Vitamin B1). We hypothesized that the administration of thiamine in its immediately available active form could provide the metabolic pathways for a supplement able to promote the metabolism of ketoacids and to reduce lactate accumulation in exercising horses. Ten horses were conditioned for 20 days to daily standardized exercise. All horses underwent a first “stress test” (ST) consisting in 1,200 meters at maximum speed on track, and were checked before and after for clinical and clinical pathology parameters. After the ST, the same animals were administered TPP (Bicarbossilasi®, ©Teknofarmas.p.a., Torino, Italy), 1 mg/Kg b.w., I.V., twice daily for seven days. At the end of treatment, a second stress test (STTPP) was performed. Post-exercise serum lactate concentration resulted in significantly lower levels (p< 0.05) after treatment with TPP (ST vs STTPP). These data suggest that supplementation with thiamine in its active form improves glucose metabolism and prevents lactate accumulation in muscle, enhancing aerobic capacity and metabolic pathways of glucose utilization during exercise

Increased luminescence efficiency by synergistic exploitation of lipo/hydrophilic co-solvency and supramolecular design

We use steady-state and time-resolved photoluminescence (PL) spectroscopy to investigate the luminescent properties of a sulfonated poly(diphenylenevinylene) lithium salt (PDV.Li) in water/propanol solutions at different concentrations, with a view to assessing its aggregation behavior. In particular, we compare results from uninsulated PDV.Li and cyclodextrin-threaded PDV.Li polyrotaxane (PDV.Li⊂β-CD). We find that addition of 1-propanol (≥20 weight%) leads to a significant blue-shift (of ∼0.20 eV) of the PL spectra, that we assign to suppressed interchain aggregation in PDV.Li solutions, with a concomitant fourfold increase in the fluorescence quantum efficiency (i.e. from 14 to 60%). Surprisingly, a moderate concentration of propanol increases further the luminescence efficiency even for PDV.Li⊂β-CD, whose supramolecular encapsulation already provides a shield against aggregation. Indeed, addition of propanol reduces the solvent polarity, and therefore helps solubilizing these materials that are still largely aromatic in nature. Interestingly, however, both uninsulated PDV.Li and polyrotaxane solutions exhibit signs of aggregation at high propanol fraction (>70%) with a distinctively weaker coupling than that of interchain states in PDV.Li at high water concentration and in pure water in particular. While we ascribe such behavior to a poor solvation of the polar moieties, we also report a different strength of aggregation for PDV.Li and PDV.Li⊂β-CD that can be attributed to the presence of the cyclodextrin rings. In PDV.Li⊂β-CD hydrogen bonding between the cyclodextrin rings may lead to closer packing between the polymer chains. We therefore suggest that a content of propanol between 30 and 70% provides a good balance of hydrophobic and hydrophilic interactions both for PDV.Li and PDV.Li⊂β-CD

Thermally-activated hardening recovery of thermo-elasto-plastic metals during annealing: constitutive modeling for the simulation of welding process

In this paper, a new thermodynamically-consistent modeling approach, dedicated to welding applications, is presented to describe the phenomenon of hardening recovery in metals during annealing. The constitutive equations are based on a classical thermo-elasto-plastic formulation, which is enhanced by a new recovery variable counterbalancing the effect of the hardening through a temperature-dependent evolution law. The identification of the model parameters is achieved through experimental compressive tests and heat treatments on 316L austenitic stainless steel. Finally, numerical simulations considering various thermomechanical loading configurations are carried out to evaluate the capabilities and limits of the model, which are furthermore illustrated in the context of welding applications through a FE example.This research was supported by Fives Cryo (Golbey, France) and Région Lorraine

Atomic Resonance and Scattering

Contains reports on four research projects.U.S. Air Force - Office of Scientific Research (Grant AFOSR-76-2972)National Science Foundation (Grant CHE79-02967)National Science Foundation (Grant PHY79-09743)Joint Services Electronics Program (Contract DAAG29-78-C-0020)Joint Services Electronics Program (Contract DAAG29-80-C-0104

A simulation tool for MRPC telescopes of the EEE project

The Extreme Energy Events (EEE) Project is mainly devoted to the study of the secondary cosmic ray radiation by using muon tracker telescopes made of three Multigap Resistive Plate Chambers (MRPC) each. The experiment consists of a telescope network mainly distributed across Italy, hosted in different building structures pertaining to high schools, universities and research centers. Therefore, the possibility to take into account the effects of these structures on collected data is important for the large physics programme of the project. A simulation tool, based on GEANT4 and using GEMC framework, has been implemented to take into account the muon interaction with EEE telescopes and to estimate the effects on data of the structures surrounding the experimental apparata.A dedicated event generator producing realistic muon distributions, detailed geometry and microscopic behavior of MRPCs have been included to produce experimental-like data. The comparison between simulated and experimental data, and the estimation of detector resolutions is here presented and discussed

Una Experiencia de Gestión de Residuos Avícolas y su Aplicación Agronómica en la Producción Hortícola del Cinturón Verde de Córdoba, Argentina.

El uso de residuos avícolas crudos en la fertilización de cultivos es una práctica común entre los productores hortícolas del Cinturón Verde de Córdoba. Sin embargo, debido al riesgo sanitario asociado al manejo de residuos pecuarios en producciones intensivas, se han generado normativas que regulan su uso agronómico. Por ello, el Equipo de Periurbanos y Agroecología (EPA), mediante la Investigación Acción Participativa (IAP), evaluó la calidad de un compost a base de residuos avícolas y su efecto en algunos parámetros de fertilidad del suelo, fisiología y productividad de un cultivo de lechuga. El compost utilizado cumplió con los valores de referencia de las normativas, siendo inocuo para las personas y los cultivos. Los resultados obtenidos, sugieren que este tipo de enmienda orgánica puede ser una alternativa prometedora, tanto para el cumplimiento del marco normativo como para la transición hacia sistemas hortícolas agroecológicos.The use of raw poultry residues as a fertilizer is a common practice among producers of the horticultural productive system in the green belt of Cordoba city. Because of the sanitary risks that this kind of management could bring for human health, there are some regulations that restrict their use. This is why the Equipo de Periurbanos y Agroecología (EPA), through Participatory Action Research, proposed to evaluate the effect of compost produced with poultry residues on soil fertility, some physiological parameters and yield. The compost used for this experiment presented the required parameters that actual regulations demand. The obtained results pointed towards an amendment that could be a promising alternative for both, the accomplishment of the regulatory framework and agroecological transitions.Instituto de Fisiología y Recursos Genéticos VegetalesFil: Gaona Flores, María Amparo. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Silbert, V. Instituto Nacional de Tecnología Industrial (INTI). Regional Córdoba; ArgentinaFil: Narmona, Luis. Fundación ArgenINTA. Delegación IFFIVE. Córdoba; ArgentinaFil: Ringuelet, A. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Pietrarelli, L. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Bianco, María Verónica. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Fisiología y Recursos Genéticos Vegetales; ArgentinaFil: Serri, Dannae Lilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; Argentin

Real-time evaluation of longitudinal peak systolic strain (speckle tracking measurement) in left and right ventricles of athletes

<p>Abstract</p> <p>Background</p> <p>Strain, and particularly Longitudinal Peak Systolic Strain (LPSS), plays a role in investigating the segmental and overall contractility of the heart which is a particularly interesting feature in athletes in whom regular training determines several morphological and functional modifications in both the ventricles, that normally work at different loads. Speckle tracking techniques assess the LPSS of LV and RV from B-mode imaging in real time, with uniform accuracy in all segments, and can verify the possible dissimilar segmental contributions of the two chambers to overall myocardial contraction. The aim of the study is to quantify the LPSS in real time in both the ventricles in order to estimate any possible different deformation properties in them during a systolic period.</p> <p>Methods</p> <p>32 subjects (20 athletes and 18 controls) were submitted to a standard echocardiographic examination at rest and after a Hand Grip (HG) stress. From a four-chamber-view image, the LPSS parameter was measured with Speckle Tracking analysis in the basal and medium-apical segments of the two ventricles, at rest and after HG.</p> <p>Results</p> <p>In both athletes and controls, LPSS values were significantly higher in the RV of athletes (RV LPSS ^{medium-apical}-23.87 ± 4.94; ^{basalfreewall}-25.04 ± 4.12 at rest) and controls (RV LPSS^{medium-apical}-25.21 ± 4.97; ^{basalfreewall}-28.69 ± 4.62 at rest) than in the LV of both (athletes LV LPSS ^{medium-apical}-18.14 ± 4.16; ^{basallateralwall}-16.05 ± 12.32; controls ^{medium-apical}-18.81 ± 2.64; ^{basallateralwall}-19.74 ± 3.84) With the HG test a significant enhancement of the LPSS(with P < .05) in the medium-apical segments of LV and RV was evident, but only in athletes; there was no modification of the standard echo-parameters in either group.</p> <p>Conclusion</p> <p>ST analysis is an easy method for investigating the contractility of the RV through deformation parameters, showing greater involvement of the RV than LV at rest. In athletes only, after isometric stress the two ventricles show particular myocardial deformation properties of the regions around the apex where the curvature of the wall is more marked. The clinical application of this new approach in athletes and normal subjects requires further investigation.</p

Atomic Resonance and Scattering

Contains reports on three research projects.U.S. Air Force - Office of Scientific Research (Grant AFOSR-76-2972)National Science Foundation (Grant CHE79-02967)National Science Foundation (Grant PHY79-09743