Influence of Cellulose Ether Particle Size on Water Retention of Freshly-Mixed Mortars

International audienceCellulose ethers are polymers frequently introduced into mortar formulations in order to improve water retention capacity and workability of the freshly-mixed materials. Physico-chemical parameters of these admixtures (molecular weight, granulometry, substitution degrees, etc) seem to have a strong influence on mortar water retention capacity. In this paper, the influence of cellulose ether particle size was studied. Two behaviors were highlighted regarding the particle size effect on mortar water retention. On the one hand, for cellulose ethers providing intermediate water retention, this parameter is fundamental: the thinner the particles, the better the water retention. The increase in water retention was explained by the rate of dissolution of every fraction which was faster for the thinnest particles. On the other hand, for admixtures providing strong water retention, the effect of this parameter was weaker or not relevant. Indeed, a cellulose ether concentration threshold was noticed, justifying this behavior

Effect of cellulose ethers on water retention in freshly-mixed mortars

International audienceCellulose ethers are polymers frequently introduced into mortar formulations in order to improve water retention capacity and workability of the freshly-mixed materials. Physico-chemical parameters of these admixtures (molecular weight, granulometry, substitution degrees, etc) seem to have a strong influence on mortar water retention capacity. In this paper, the influence of cellulose ether molecular weight on mortar water retention and its consistency was studied. Moreover, a new method was used to evaluate mortar consistency, named Consistor Baronnie method. This method was confirmed with rheological measurements

Cellulose ethers influence on water retention and consistency in cement-based mortars

International audienceCellulose ethers (CE) are commonly used as additives to improve the quality of cement-based materials. As admixtures, they improve the properties of mortars such as water retention, workability, and open time. Also, polysaccharides such as starch derivatives are used to improve the consistency of the fresh material. The properties of cement-based mortars at fresh state were investigated. The effect of CE and their physico-chemical parameters (molecular weight, substitution degrees, etc.) on both water retention and rheological properties of mortars were studied. Moreover, some starch derivatives were also examined in order to better understand the water retention mechanisms. Rheological measurements showed that CE have a thickening effect for a content of 0.27 wt.%. Besides, a fundamental effect of CE molecular weight on mortar consistency and its water retention capability was highlighted. Finally, the comparison with starch ethers proved that, for those admixtures, water retention is not directly linked to mortar's viscosity

Chronic adult T-cell Leukemia in a young male after blood transfusion as a newborn

Human T-cell Lymphotropic virus type 1 (HTLV-1) is the etiological agent of Adult T-cell Leukemia/Lymphoma (ATLL) and HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HTM/TSP). Areas of extremely high HTLV-1 prevalence are surrounded by areas of middle or very low prevalence. ATLL is an aggressive lymphoproliferative malignancy of peripheral T cells, with an incidence of less than 5% in HTLV-1-infected individuals. ATLL develops in the majority of cases in individuals who were infected with HTLV-1 by their mothers due to prolonged breastfeeding. In non-endemic areas, ATLL is usually limited to immigrants from endemic regions. Very few cases of ATLL have been diagnosed in recipient patients few years after an organ transplantation or blood transfusion worldwide. Achieving an accurate and fast diagnosis of ATLL can be challenging due to the lack of professional experience, delayed consultation and difficulty in its subclassification. We present a case of a delayed onset of a chronic ATLL in an 18-years-old male that was transfused with blood components as a premature newborn in Buenos Aires, a non-endemic city of South America.Fil: Colucci, Magalí. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Cánepa, Camila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Ruggieri, Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Halperin, Nora Silvia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Rojas, Francisca. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Altube, Alejandra. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Cabral Lorenzo, María Cecilia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Deves, Alberto. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Hermine, Olivier. Universite de Paris V; FranciaFil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentin

Chronic adult T-cell leukemia after transmission of human T cell lymphotropic virus type 1 by blood transfusion as a newborn

En el mundo existen aproximadamente 20 millones de individuos infectados por el virus linfotrópico T humano tipo 1 (HTLV-1), de los cuales 3 a 5% desarrollarán alguna de las patologías asociadas. La infección por HTLV-1 tiende a encontrarse focalizada endémicamente en regiones geográficas bien definidas, como sucede en el noroeste argentino. El HTLV-1 se trasmite por vía sexual, parenteral y vertical y es el causante de la leucemia/linfoma a células T del adulto (LLCA), una enfermedad linfoproliferativa agresiva que se desarrolla mayoritariamente cuando la infección fue por lactancia prolongada. En áreas de baja prevalencia generalmente se desarrolla en inmigrantes, descendientes o parejas sexuales de individuos provenientes de áreas endémicas. La LLCA se clasifica en aguda, crónica, linfoma y latente. Muy pocos casos han sido diagnosticados post-transfusión sanguínea o post trasplante de órganos. Arribar a un diagnóstico rápido y certero del tipo de LLCA es un desafío que impacta directamente en la supervivencia del individuo. Presentamos el caso de una LLCA crónica que se desarrolló 18 años después de recibir una transfusión sanguínea al nacer en la ciudad de Buenos Aires, ciudad de Sudamérica no endémica para HTLV-1.Approximately 20 million individuals are infected by human T-cell lymphotropic virus type 1 (HTLV1) worldwide and 3-5% of them will develop an associated pathology. Areas of extremely high HTLV-1 prevalence as the Northwest region of Argentina are surrounded by areas of middle or very low prevalence. HTLV-1 is transmitted via parenteral, sexual and vertical and causes adult T cell leukemia lymphoma (ATLL), an aggressive lymphoproliferative malignancy of peripheral T cells that develops in the majority of cases in individuals who were infected with HTLV-1 by their mothers due to prolonged breastfeeding. In non-endemic areas, ATLL is usually limited to immigrants from endemic regions. ATLL is classified as acute, chronic, lymphoma and smoldering. Very few cases of ATLL have been diagnosed in recipient patients after an organ transplantation or blood transfusion. Achieving an accurate and fast diagnosis of ATLL can be challenging for the direct impact on their life expectancy. We present the case of a delayed onset of a chronic ATLL in an 18-years-old male who was transfused with blood components as a premature newborn in Buenos Aires, a non-endemic city for HTLV-1 infection in South America.Fil: Colucci, Magalí. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Berini, Carolina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Cánepa, Camila. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Ruggieri, Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; ArgentinaFil: Halperin, Nora Silvia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Rojas, Francisca. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Altube, Alejandra. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Lorenzo Cabral, Cecilia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Deves, Alberto. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Hermine, Olivier. Inserm; Francia. Centre National de la Recherche Scientifique; Francia. Universite de Paris V; FranciaFil: Biglione, Mirna Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentin

Chronic adult T-cell Leukemia in a young male after blood transfusion as a newborn

Human T-cell Lymphotropic virus type 1 (HTLV-1) is the etiological agent of Adult T-cell Leukemia/Lymphoma (ATLL) and HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HTM/TSP). Areas of extremely high HTLV-1 prevalence are surrounded by areas of middle or very low prevalence. ATLL is an aggressive lymphoproliferative malignancy of peripheral T cells, with an incidence of less than 5% in HTLV-1-infected individuals. ATLL developed in the majority of cases in individuals who were infected with HTLV-1 by their mothers due to prolonged breastfeeding. In non-endemic areas, ATLL is usually limited to immigrants, their sexual partners and descendants from endemic regions. Very few cases of ATLL have been diagnosed in recipient patients few years after an organ transplantation or blood transfusion worldwide. Achieving an accurate and fast diagnosis of ATLL can be challenging due to the lack of professional experience, delayed consultation and difficulty in its sub-classification. We present a case of a delayed onset of a chronic ATLL in an 18-years-old male who was transfused with blood components as a premature newborn in Buenos Aires, a non-endemic city of South America

Attacking blood-borne parasites with mathematics

Central carbon metabolism is important to cells as it supplies free energy in the form of ATP and the building blocks for new cells. Parasites harvest many of the components they require from their hosts, but they still have to generate ATP themselves, making the metabolic pathways that generate ATP essential to the parasites' survival and thereby potential target pathways for antiparasitic drugs. Metabolic networks often consist of many components that interact with each other via nonlinear kinetics.The behavior of the network arises from the interaction of the components within and outside the network. To understand network behavior, experimental measurements on the components should be integrated through computational approaches. In this chapter, we present an overview of how experiment-driven mathematical models have provided insights on important aspects of parasite metabolism and have aided in elucidating potent antiparasitic drug targets within metabolism.</p