Liquid recirculation in microfluidic channels by the interplay of capillary and centrifugal forces

We demonstrate a technique to recirculate liquids in a microfluidic device, maintaining a thin fluid layer such that typical diffusion times for analytes to reach the device surface are < 1 min. Fluids can be recirculated at least 1000 times across the same surface region, with no change other than slight evaporation, by alternating the predominance of centrifugal and capillary forces. Mounted on a rotational platform, the device consists of two hydrophilic layers separated by a thin pressure-sensitive adhesive (PSA) layer that defines the microfluidic structure. We demonstrate rapid, effective fluid mixing with this device

Editorial

Presentamos aquí un espacio de discusión y reflexión en torno a los desafíos teóricos, metodológicos y epistemológicos que implican pensar las migraciones contemporáneas. Es un compromiso ético en la producción de conocimiento acercarnos de manera clara a nuevas perspectivas y posibilidades de encuentro y vínculo de las relaciones en escenarios inéditos donde las identificaciones se están erigiendo

Editorial

Presentamos aquí un espacio de discusión y reflexión en torno a los desafíos teóricos, metodológicos y epistemológicos que implican pensar las migraciones contemporáneas. Es un compromiso ético en la producción de conocimiento acercarnos de manera clara a nuevas perspectivas y posibilidades de encuentro y vínculo de las relaciones en escenarios inéditos donde las identificaciones se están erigiendo

Type 1 Diabetes Mellitus reversal via implantation of magnetically purified microencapsulated pseudoislets

[Abstract] Microencapsulation of pancreatic islets for the treatment of Type I Diabetes Mellitus (T1DM) generates a high quantity of empty microcapsules, resulting in high therapeutic graft volumes that can enhance the host’s immune response. We report a 3D printed microfluidic magnetic sorting device for microcapsules purification with the objective to reduce the number of empty microcapsules prior transplantation. In this study, INS1E pseudoislets were microencapsulated within alginate (A) and alginate-poly-L-lysine-alginate (APA) microcapsules and purified through the microfluidic device. APA microcapsules demonstrated higher mechanical integrity and stability than A microcapsules, showing better pseudoislets viability and biological function. Importantly, we obtained a reduction of the graft volume of 77.5% for A microcapsules and 78.6% for APA microcapsules. After subcutaneous implantation of induced diabetic Wistar rats with magnetically purified APA microencapsulated pseudoislets, blood glucose levels were restored into normoglycemia (<200 mg/dL) for almost 17 weeks. In conclusion, our described microfluidic magnetic sorting device represents a great alternative approach for the graft volume reduction of microencapsulated pseudoislets and its application in T1DM disease.Universidad del País Vasco; ESPPOC 16/65Universidad del País vasco; EHUa16/06Gobierno Vasco; IT907-16Gobierno Vasco; KK-2017/0000088Gobierno Vasco; 307616FKA4Ministerio de Economía y Competitividad; RYC-2012-1079

Protein pattern transfer for biosensor applications

This paper presents a very simple, industrially scalable method for transferring a high-resolution, biologically active protein pattern from one substrate to another. We demonstrate the transfer of a protein pattern formed initially by microcontact printing from a silicon surface (to which this form of printing is applicable) onto a glass or polymer substrate, almost independently of the surface/bulk properties of the second substrate. A very thin, spin-coated layer of a sugar is used to preserve the structure and organization of proteins during the subsequent plasma deposition of a siloxane polymer, after which the protein pattern could simply be peeled off the silicon substrate and glued onto any other desired substrate. © 2009 Elsevier B.V. All rights reserved

First molecular characterization of canine hepatozoonosis in Argentina: evaluation of asymptomatic Hepatozoon canis infection in dogs from Buenos Aires

Canine hepatozoonosis is an expanding tick-borne disease in Argentina. Hepatozoonosis was studied during 1 year in six dogs from the same household in Buenos Aires. Blood parasitemia with Hepatozoon gamonts was found in five dogs and all six were positive by PCR for Hepatozoon sp. Although the levels of parasitemia fluctuated during the year, no clinical signs of disease were detected during the follow up period. Amplification and sequencing of a 650 bases fragment of the 18S rRNA gene from all six dogs yielded fragments that were 99% identical to H. canis. The results of the partial 18S rRNA genotyping with the sub-clinical course of infection and lack of severe hematological abnormalities are compatible with clinical and molecular descriptions of Hepatozoon canis infection from other areas of the world. This is the first molecular characterization of Hepatozoon from Argentina.Facultad de Ciencias Veterinaria

Epidemiología de la hepatozoonosis canina en Buenos Aires (Argentina) durante el período 2002-2008

La hepatozoonosis canina es una enfermedad transmitida por garrapatas causada por un protozoario del género Hepatozoon. Esta enfermedad fue descripta en Asia, Europa, Sud y Norte América. Desde el primer reporte en Buenos Aires (Argentina) en 1999, se observo un progresivo aumento en la tasa de infección y en la actualidad puede encontrarse en un gran número de perros. El presente estudio se enfoca en la descripción de algunas características epidemiológicas de la infección por Hepatozoon en Buenos Aires durante los últimos años.Facultad de Ciencias Veterinaria

Model validation for a noninvasive arterial stenosis detection problem

Copyright @ 2013 American Institute of Mathematical SciencesA current thrust in medical research is the development of a non-invasive method for detection, localization, and characterization of an arterial stenosis (a blockage or partial blockage in an artery). A method has been proposed to detect shear waves in the chest cavity which have been generated by disturbances in the blood flow resulting from a stenosis. In order to develop this methodology further, we use both one-dimensional pressure and shear wave experimental data from novel acoustic phantoms to validate corresponding viscoelastic mathematical models, which were developed in a concept paper [8] and refined herein. We estimate model parameters which give a good fit (in a sense to be precisely defined) to the experimental data, and use asymptotic error theory to provide confidence intervals for parameter estimates. Finally, since a robust error model is necessary for accurate parameter estimates and confidence analysis, we include a comparison of absolute and relative models for measurement error.The National Institute of Allergy and Infectious Diseases, the Air Force Office of Scientific Research, the Deopartment of Education and the Engineering and Physical Sciences Research Council (EPSRC)

Judicial disagreement need not be political: dissent on the Estonian Supreme Court

I investigate the non-unanimous decisions of judges on the Estonian Supreme Court. I argue that since judges on the court enjoy high de jure independence, dissent frequently, and are integrated in the normal judicial hierarchy, the Estonian Supreme Court is a crucial case for the presumption that judicial disagreement reveals policy preferences. I analyse dissenting opinions using an ideal point response model. Examining the characteristics of cases which discriminated with respect to the recovered dimension, I show that this dimension cannot be interpreted as a meaningful policy dimension, but instead reflects disagreement about the proper scope of constitutional redress