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1.
J Contam Hydrol ; 263: 104343, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38631090

RESUMO

The long-term management of tailings from former uranium (U) mines requires an in-depth understanding of the hydrogeological processes and water flow paths. In France, most of the legacy U mines are located in fractured crystalline (plutonic) rocks, where the intrinsic subsurface heterogeneity adds to the uncertainties about the former extraction and milling activities and the state of the mine when production was ceased. U ores were mainly processed by sulfuric acid leaching, leading to high-sulfate-content mill tailings now contained in several tailing storage facilities (TSFs). The La Ribière site, located in western central France, is a former open-pit and underground U mine, closed in 1992 and used to store mill tailings. This site is being used as a test case to establish a workflow in order to explain and predict water flow and subsurface contaminant transport. A conceptual model of water flow and sulfate transport, at the scale of the La Ribière watershed, is first developed based on available information and hydrogeochemical monitoring. Recent geophysical investigations allows refining this model. Electrical Resistivity Tomography (ERT) proves to be efficient at localizing the extent of the highly conductive sulfate plume inherited from the U-mill tailings, but also at imaging the weathering profile. Magnetic Resonance Sounding (MRS), despite the limited signal intensity due to the low porosity in crystalline rocks, gives some insight into the porosity values, the depth of the fractured layer and the location of the low-porosity ore-processing muds. Based on this conceptual model, a 3D flow and non-reactive transport model with the METIS code is developed and calibrated. This model allows predicting the evolution of the sulfate plume, but will also be used in future investigations, to build reactive transport models with simplified hydrogeology for U and other reactive contaminants.


Assuntos
Mineração , Urânio , Movimentos da Água , Urânio/química , França , Modelos Teóricos , Poluentes Radioativos da Água/análise , Monitoramento Ambiental/métodos , Dióxido de Silício/química , Água Subterrânea/química , Incerteza , Sulfatos/química
3.
Gynecol Obstet Fertil Senol ; 49(6): 538-546, 2021 06.
Artigo em Francês | MEDLINE | ID: mdl-33166702

RESUMO

Vulvar carcinomas represent 4% of all gynaecological cancers with 838 new cases in France in 2018. The precursor lesions of vulvar carcinomas are differentiated vulvar intraepithelial lesion (dVIN) in a context of lichen sclerosus and vulvar high-grade squamous intraepithelial lesion (HSIL) link to human papillomavirus (HPV) infection. Three typical clinical forms of HSIL are described: the Bowenoid papulosis, the Bowen's disease and the confluent VIN. Histopathology cannot differentiate effectively these two types of lesions. P16 and P53 immunostaining are valuable tools to respectively assess HPV infection and divide different types of dVIN. However, P53 immunostaining is still lacking sensibility to detect dVIN. First line therapies are medical treatment excluding the cases with a doubt of invasion. The gold standard treatment for dVIN and vulvar HSIL are respectively topical corticosteroids and imiquimod. Primary prevention for vulvar HSIL and dVIN are respectively HPV vaccination and early treatment of lichen sclerosus. Destructive therapy can be used in case of medical treatment failure such as CO2 laser, cryotherapy, dynamic phototherapy. Surgical indications should be carefully assessed between the risk of recurrence, the spread of the lesions, the aesthetic and functional aspect. Surgical procedures consist in either superficial vulvectomy or radical vulvectomy with or without flap reconstruction. Recurrence rate after surgery is around 20%.


Assuntos
Carcinoma in Situ , Carcinoma de Células Escamosas , Infecções por Papillomavirus , Lesões Pré-Cancerosas , Neoplasias Vulvares , Carcinoma in Situ/terapia , Feminino , Humanos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/terapia , Neoplasias Vulvares/terapia
4.
Nanotechnology ; 23(49): 495501, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23165395

RESUMO

The biofunctionalization of nanoelectromechanical systems (NEMS) is critical for the development of new classes of biosensors displaying improved performance and higher levels of integration. In this paper we propose a modified microcontact process (µCP) in order to biofunctionalize arrays of NEMS with a probe molecule on the active sensing areas together with an anti-fouling layer on the passive areas in a single, self-aligned step. We demonstrate the adequate functionalization/anti-fouling of arrays of freestanding nanocantilevers as dense as 10(5) nanostructures cm(-2) by using both fluorescence microscopy and dynamic measurements of the structures' resonant frequency. The proper bioactivity of an antibody deposited onto the cantilevers and the blocking property of a bovine serum albumin layer are both assessed by incubating specific and non-specific tagged secondary antibodies followed by fluorescence imaging. Furthermore, measurement of the resonant frequency of the nanocantilevers before and after functionalization and biological recognition demonstrate that using µCP for device functionalization does not damage the nanostructures and preserves the mechanical sensing capability of our NEMS.


Assuntos
Técnicas Biossensoriais/instrumentação , Imunoensaio/instrumentação , Sistemas Microeletromecânicos/instrumentação , Análise em Microsséries/instrumentação , Impressão Molecular/métodos , Nanopartículas/química , Nanotecnologia/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
5.
Int J Cosmet Sci ; 34(4): 311-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22571718

RESUMO

Chronic sun exposure and especially UVA wavelengths are responsible for long-term clinical skin changes such as photoageing and photocancers. The objectives of the present study were to analyse the contractile activity of fibroblasts irradiated with several doses of UVA and to evaluate the preventive, protective and restoring effects of a mixture of monomethylsilanetriol mannuronate and dimethylsilanediol salicylate. The forces generated by fibroblasts in tense collagen lattices were quantified using Glasbox device before and after UVA irradiation and the addition of a mixture of monomethylsilanetriol mannuronate and dimethylsilanediol salicylate. The production of collagen was also evaluated before and after irradiation and with and without the presence of a mixture of monomethylsilanetriol mannuronate and dimethylsilanediol salicylate. A dose of 3 J cm(-2) of UVA showed more than 50% of mortality in fibroblast population after 48 h and significant decreases in contractile forces developed by irradiated fibroblasts and collagen I production. One percentage of a mixture of monomethylsilanetriol mannuronate and dimethylsilanediol salicylate protected fibroblasts from UVA irradiation and made it possible to restore their capacity to the same level as fibroblasts that were not irradiated. It also tended to restore the capacity to synthesize collagen I. These results show that the use of the new device Glasbox makes it possible to evaluate a possible preventive and repairing effect of a cosmetic functional active on photoageing.


Assuntos
Silanos/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos , Adulto , Colágeno Tipo I/metabolismo , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/efeitos da radiação , Humanos , Pele/citologia , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos da radiação , Resistência à Tração
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