Classifying zones of suitability for manual drilling using textural and hydraulic parameters of shallow aquifers: a case study in northwestern Senegal.

A method is proposed that uses analysis of borehole stratigraphic logs for the characterization of shallow aquifers and for the assessment of areas suitable for manual drilling. The model is based on available borehole-log parameters: depth to hard rock, depth to water, thickness of laterite and hydraulic transmissivity of the shallow aquifer. The model is applied to a study area in northwestern Senegal. A dataset of boreholes logs has been processed using a software package (TANGAFRIC) developed during the research. After a manual procedure to assign a standard category describing the lithological characteristics, the next step is the automated extraction of different textural parameters and the estimation of hydraulic conductivity using reference values available in the literature. The hydraulic conductivity values estimated from stratigraphic data have been partially validated, by comparing them with measured values from a series of pumping tests carried out in large-diameter wells. The results show that this method is able to produce a reliable interpretation of the shallow hydrogeological context using information generally available in the region. The research contributes to improving the identification of areas where conditions are suitable for manual drilling. This is achieved by applying the described method, based on a structured and semi-quantitative approach, to classify the zones of suitability for given manual drilling techniques using data available in most African countries. Ultimately, this work will support proposed international programs aimed at promoting low-cost water supply in Africa and enhancing access to safe drinking water for the population.

Une méthode est. proposée utilisant l'analyse des logs stratigraphiques des forages pour la caractérisation des aquifères peu profonds et pour l'évaluation des zones favourable pour le forage manuel. Le modèle repose sur l'analyse des paramètres extraits des logs de forage disponibles: profondeur au socle, profondeur au niveau piézométrique, épaisseur de la latérite et transmissivité hydraulique de l'aquifère peu profond. Le modèle est. appliqué à une zone d'étude dans le nord-ouest du Sénégal. Un ensemble de données de logs de forages a été traité en utilisant l'application informatique TANGAFRIC développée au cours de la recherche. Après une procédure manuelle pour attribuer une catégorie standardisée décrivant les caractéristiques lithologiques, l'étape suivante et une extraction automatique des différents paramètres texturaux et l'estimation de la conductivité hydraulique en utilisant des valeurs de référence disponibles dans la littérature. Les valeurs de conductivité hydraulique estimées à partir des données stratigraphiques ont été partiellement validées, en les comparant aux valeurs mesurées à partir d'une série de pompages d'essais réalisés sur des forages de grand diamètre. Les résultats indiquent que cette méthode permet de produire une interprétation fiable du contexte hydrogéologique peu profond en utilisant des informations généralement disponibles dans la région. La recherche contribue à améliorer l'identification de régions pour lesquelles des conditions sont en faveur de forages manuels. Ceci est. réalisé en appliquant la méthode décrite, basée sur une approche structurée et semi-quantitative, pour classer l'aptitude de zones à des techniques données de forage manuel en utilisant les données disponibles dans la plupart des pays africains. En fin de compte, ce travail appuiera les programmes internationaux proposés visant à promouvoir l'approvisionnement en eau potable à un faible coût en Afrique et à améliorer l'accès à l'eau potable pour la population.

Se propone un método que utiliza el análisis de registros estratigráficos de pozos para la caracterización de acuíferos poco profundos y para la evaluación de áreas aptas para la perforación manual. El modelo se basa en el análisis de parámetros extraídos de registros de pozos disponibles: profundidad de la roca dura, profundidad del agua, espesor de laterita y transmisividad hidráulica del acuífero poco profundo. El modelo se aplica a un área de estudio en el noroeste de Senegal. Un conjunto de datos de registros de perforaciones se ha procesado utilizando un paquete de software (TANGAFRIC) desarrollado durante la investigación. Después de un procedimiento manual para asignar una categoría estándar que describe las características litológicas, el siguiente paso es la extracción automatizada de diferentes parámetros texturales y la estimación de la conductividad hidráulica usando los valores de referencia disponibles en la literatura. Los valores de conductividad hidráulica estimados a partir de datos estratigráficos han sido parcialmente validados, comparándolos con valores medidos de una serie de ensayos de bombeo realizados en pozos de gran diámetro. Los resultados muestran que este método es capaz de producir una interpretación confiable del contexto hidrogeológico superficial usando información generalmente disponible en la región. La investigación contribuye a mejorar la identificación de áreas donde las condiciones son aptas para la perforación manual. Esto se logra aplicando el método descrito, basado en un enfoque estructurado y semicuantitativo, para clasificar la idoneidad para determinadas técnicas de perforación manual utilizando datos disponibles en la mayoría de los países africanos. En última instancia, este trabajo apoyará los programas internacionales propuestos para promover el suministro de agua a bajo costo en África y mejorar el acceso al agua potable para la población.

Um método é proposto usando análise estratigráfica de perfis de poços para a caracterização de aquíferos rasos e avaliação de áreas favoráveis para perfuração manual. O modelo é baseado na análise dos parâmetros extraídos de perfis de poços disponíveis: profundidade da rocha dura, profundidade da água, espessura da laterita, e transmissividade hidráulica do aquífero raso. O modelo é aplicado a uma área de estudo no noroeste do Senegal. Os perfis dos poços foram processados usando o programa de computador (TANGAFRIC) desenvolvido durante a pesquisa. Após um procedimento manual para assinalar uma categoria padrão descrevendo as características litológicas, o próximo passo é a extração automática de diferentes parâmetros texturais e a estimativa da condutividade hidráulica usando os valores de referência disponíveis na literatura. Os valores de condutividade hidráulica estimados de dados de estratigrafia foram parcialmente validados comparando estes com valores medidos através de uma série de testes de bombeamento realizados em poços de grande diâmetro. Os resultados mostram que este método é capaz de produzir uma interpretação confiável do contexto hidrogeológico raso usando informações disponíveis na região. A pesquisa contribui para promover a identificação de áreas onde as condições são favoráveis para perfuração manual. Isso é obtido aplicando o método descrito, baseado no processo estruturado e semiquantitativo para classificar a favorabilidade para uma certa técnica de perfuração manual usando os dados disponíveis na maioria dos países Africanos. Por último, este trabalho suportará programas internacionais propostos com o objetivo de promover o abastecimento de água a baixo custo na África e aumentar o acesso seguro a água potável para a população.

[Partiturogram: (new) tool in the evaluation of an opera roles]. / Le partiturogramme: (nouvel) outil dans l'évaluation du profil vocal des rôles d'opéra.

The partiturogram is a tool that was defined in the 1990s by Franco Fussi. It aims to display all the music notes of an opera role as a histogram. Several parameters are then calculated in order to define the vocal profile of the role, as well as help the singer choose from various options. We have decided to use this tool to study Norma and Sonnambula, two roles which were specifically written for the same singer described as a dramatic soprano. Over time, both roles have been allocated to radically different voices. The partiturogram confirms the similarity of the vocal types of both roles, but gives no explanation as to the differences in the casting decisions. We have therefore established its limits, and we have submitted a study including new parameters in order to refine the characterization of roles.

[Prevention of laryngeal nerve lesions in thyroid surgery]. / La prevenzione delle lesioni dei nervi laringei nella chirurgia della tiroide.

The authors analyse problems related to laryngeal nerves in matters of thyroid surgery. As a matter of fact laryngeal nerve injury is still one of the most common complications for patients undergoing thyroid surgery. Although the sharp reduction in this drawback, due to a better anesthesiological technique and a wider surgical experience, the most representative case report show an incidence ranging from 3% to 5%. After a short introduction on surgical anatomy, attention is drawn to the "recurrent nerve risk" but also the superior laryngeal nerve too, often injured with modifications of the vocal tone and serious consequences for particular professional groups. There fore it is of basic importance, for surgeons performing thyroid surgery, to dissect the recurrent nerve for all its length, that is from the crossing with the inferior thyroid artery to the point where it enters the cricothyroid cartilage; in order not to damage the thin nervous branches and eventually anatomic variations that, when looked for, are cause of mistakes even for the most experienced surgeons.

Pharmacological profile of a native dermatan sulfate.

We performed different "in vivo" investigations to study the pharmacological properties of a native DS: anti-thrombosis by the stasis model, bleeding potential by tail transection bleeding time and template bleeding time, and profibrinolysis by a growing thrombus model and by an established thrombus model. The results suggest that DS is a safe antithrombotic drug by i.v. administration without bleeding potential, even at very high doses (up to 16 mg/Kg). DS has shown a protective index of at least 4 in contrast to heparin that has shown a protective index of 1. The profibrinolytic models so far studied did not evidence a clear profibrinolytic contribution to the antithrombotic properties of DS, but showed a prolonged antithrombotic action that cannot be explained only by the heparin cofactor II potentiation.

Synthetic and natural factors promoting production of murine and human monoclonal antibodies.

Human endothelial culture supernatant (HECS) contains factor(s) which promote the growth and the stability of hybridoma cells, and in these respects is superior to the commonly used feeder cells. In particular: HECS increases the recovery of hybridomas after fusion as compared to that in the presence of feeder cells; HECS can substitute feeder cells supporting the growth of hybridomas at the single-cell level under limiting dilution conditions; HECS prolongs the stability of human-mouse hybridomas producing human immunoglobulins (Ig). The active principle which is present in HECS can be different from IL-6. Furthermore the effects of a polyamine derivative, carboxyethyl gamma-aminobutyric acid (CEGABA), were studied on the growth of hybridomas and Epstein-Barr Virus-transformed cell lines. CEGABA enhances the growth of hybridomas through all the steps of hybridoma technology and induces the formation of a large number of EBV-transformed lymphocytes, when added to the culture medium immediately after EBV infection. However, CEGABA shows only a moderate effect on the stability of EBV-transformed cell lines over time, and does not effect the growth of stabilized cell lines. It is possible that CEGABA acts on cells other than EBV-transformed lymphocytes (in fact, after EBV infection all types of mononuclear cells from the blood are present in the culture) and indirectly promotes the growth of EBV-transformed lymphocytes.

Experimental study on central effects of carboxyethyl-gamma-aminobutyric acid (CEGABA).

The central effects of carboxyethyl-gamma-aminobutyric acid (CEGABA) have been studied both in rabbits and in the guinea pig myoclonus model. This drug caused EEG synchronization and behavioural sedation both after intravenous (i.v.) and intracerebroventricular (i.c.v.) administration in a dose-dependent manner, in rabbits. CEGABA showed a protective action against myoclonus induced by means of L-5-HTP in young guinea pigs. These data substantiate the hypothesis that CEGABA is a drug active on the central nervous system and probably exerts its action by strengthening cortical inhibition and/or directly acting on lower brainstem.

Carboxyethyl gamma-aminobutyric acid, a polyamine derivative, improves the recovery of EBV-transformed lymphocytes.

A polyamine derivative, carboxyethyl - Aminobutyric Acid (CEGABA), induces the formation of a large number of Epstein-Barr Virus (EBV) transformed lymphocytes, when added to the culture medium immediately after EBV infection. However, CEGABA shows only a moderate effect on the stability of EBV-transformed cell lines over time, and does not affect the growth of stabilized cell lines. It is possible that CEGABA acts on cells other than EBV transformed lymphocytes (in fact, after EBV infection all types of mononuclear cells from the blood are present in the culture) and indirectly promotes the growth of EBV transformed lymphocytes.

Identification of N-carboxyethyl gamma-aminobutyric acid in bovine brain and human cerebrospinal fluid.

The di-carboxylated derivative of spermidine, N-carboxyethyl gamma-aminobutyric acid (CEGABA) has been identified in bovine brain and human cerebrospinal fluid by HPLC. This discovery strongly suggests the existence of a metabolic pathway connecting polyamines and GABA via putreanine and CEGABA through progressive oxidative deamination of the amino terminal groups in spermidine.

Carboxyethyl gamma-aminobutyric acid, a polyamine derivative molecule with a growth effect on hybridomas.

An increased proliferation of hybridomas is induced by a polyamine derivative molecule, CEGABA (carboxyethyl gamma-aminobutyric acid). The effects of CEGABA and CR-ECGS (endothelial cell growth supplement) on hybridoma growth are similar. However, both factors are less efficient than HECS (human endothelial culture supernatant) in inducing hybridoma growth through all the steps of hybridoma production, including: recovery after fusion, cloning, and proliferation.

Normal and low molecular weight heparins: interaction with human platelets.

Porcine mucosal heparin was chemically depolymerized. The depolymerization was stopped at different steps to obtain two low molecular weight (LMW) heparins with a molecular weight of 10 000 and 6000, respectively. The LMW heparins were tested in vitro for anti-clotting activities and for platelet serotonin release in different systems in comparison with normal heparins, dermatan and heparan sulphate. After addition of various amounts of heparin preparations to washed platelets, no significant release was observed for all tested heparins. On the contrary, different heparins showed an inhibition of serotonin-release induced by collagen in platelet rich plasma, whereas the ADP-induced release was increased. The effect on the platelet release appears related to the molecular weight. In fact, it is significant only for normal heparins whereas it is not for LMW heparins. A good relation was observed, also, between anti-activated factor X activity/antiglobal clotting activity (Xa/APTT) ratio of different heparins and the effect on platelet release.

RNA and protein synthesis in rat brain during exercise. Effect of arginine and some phosphorylated amino acids.

RNA and protein synthesis is noticeably depressed in the brain of swimming rats. Repeated oral administration of phosphothreonine, phosphoserine or arginine is susceptible of improving brain macromolecular synthesis. A parallel induction is observed on spermine and spermidine accumulation, particularly evident when arginine is used. The anti-fatigue effect of phosphorylated amino acids or arginine may be associated with the observed restoration of brain macromolecular synthesis via polyamine accumulation.

Activation of lipase by a factor present in the gall-bladder epithelium.

The action of a bovine gall-bladder extract is studied on two lipolytic systems: the pancreas lipase and the plasma lipoproteinlipase. For pancreas lipase the lipolytic activity of pancreas homogenates of different species is evaluated in the presence of different quantities of gall-bladder extract. For plasma lipoproteinlipase, the enzyme is induced by injection of optimal doses of heparin associated with different quantities of gall-bladder extract and the activity is evaluated by measuring the clarifying power of the plasmas of the treated animals. The results confirm that the gall-bladder contains a factor activating the pancreas lipase and put in evidence some differences between lipase activities in different species. For plasma lipolytic activation, the action of the gall-bladder extract is particularly evident in the inductive phase of lipoproteinlipase, according to a typical process of saturation.