Sökresultat

Filtyp

Din sökning på "*" gav 535696 sökträffar

Acoustophoretic manipulation of sub-micron objects enabled by density gradients

Direct and precise manipulation of sub-micron particles such as bacteria, platelets, organelles, microvesicles, exosomes or virus particles is challenging. We describe for the first time how acoustic streaming in the bulk can be efficiently reduced by introducing a density or compressibility gradient and that this enables focusing of 500-nm-diameter particles in a standard acoustophoresis channel.

Twenty second acoustofluidic whole blood hematocrit assay

This abstract reports a novel acoustofluidic method to measure the hematocrit level of a whole blood sample within 20 seconds. The method is substantially faster than conventional centrifugation methods, has no moving parts and can be fully automated and integrated with further unit operations for analysis of blood samples at the point of care [1].

Microfluidic separation of parasites and parasite-infected cells from blood for the diagnosis of leishmaniasis

Microfluidic techniques were applied to the separation of parasite and parasite-infected cells from blood to facilitate the detection of leishmaniasis, a disease representing a high burden in the developing world and for which new diagnostic tools are urgently needed. Leishmania mexicana promastigotes were successfully separated from red blood cells in a deterministic lateral displacement device.

Detailed characterization of plasmids carrying resistance genes using optical DNA mapping

We present an assay, based on optical DNA mapping in nanochannels that is capable of characterizing the plasmid content of bacterial isolates resistant to antibiotics in a fast an detailed way. In a single experiment we determine the number of different plasmids in each sample, their size, as well as a barcode that can be used for plasmid identification and tracing. In addition we demonstrate that

Africa's Skill Tragedy : Does Teachers' Lack of Knowledge Lead to Low Student Performance?

We study the importance of teacher subject knowledge for student performance in Sub-Saharan Africa using unique international assessment data for sixth-grade students and their teachers. To circumvent bias due to unobserved student heterogeneity, we exploit variation within students across math and reading. Teacher subject knowledge has a modest impact on student performance. Exploiting vast cross

Methacholine challenge tests to demonstrate therapeutic equivalence of terbutaline sulfate via different Turbuhaler® devices in patients with mild to moderate asthma : Appraisal of a four-way crossover design

Background/Objective To demonstrate therapeutic equivalence of terbutaline via two different Turbuhaler® devices by evaluating its protective effect against methacholine-induced bronchoconstriction in stable asthma. Methods In this double-blind, double-dummy, multicentre, single-dose, 4-way crossover study, patients with stable mild-to-moderate asthma (FEV1 ≥80% predicted) were randomised to 0.5 o

The Effect of Working Hours on Health

Does working time causally affect workers' health? We study this question in the context of a French reform which reduced the standard workweek from 39 to 35 hours, at constant earnings. Our empirical analysis exploits variation in the adoption of this shorter workweek across employers, which is mainly driven by institutional features of the reform and thus exogenous to workers' health. Difference

Tensile behavior of single-crystal nano-sized copper beams with voids

The tensile response under displacement controlled loading of nano-sized single crystal Cu beams, solid or holding square shaped through-the thickness voids, have been investigated through 3D molecular dynamics simulations using free-ware LAMMPS [1]. For the same beam size and void height, the void width along the beam length axis was varied. Two different crystallographic orientations were consid

Solar biosupercapacitor

Here we report on an entirely new kind of bioelectronic device – a solar biosupercapacitor, which is built from a dual-feature photobioanode combined with a double-function enzymatic cathode. The self-charging biodevice, based on transparent nanostructured indium tin oxide electrodes modified with biological catalysts, i.e. thylakoid membranes and bilirubin oxidase, is able to capacitively store e

Do nanoparticles provide a new opportunity for diagnosis of distal airspace disease?

There is a need for efficient techniques to assess abnormalities in the peripheral regions of the lungs, for example, for diagnosis of pulmonary emphysema. Considerable scientific efforts have been directed toward measuring lung morphology by studying recovery of inhaled micron-sized aerosol particles (0.4-1.5 μm). In contrast, it is suggested that the recovery of inhaled airborne nanoparticles ma

Validation of the Italian Version of the Caregiver Abuse Screen among Family Caregivers of Older People with Alzheimer's Disease

Introduction. Elder abuse is often a hidden phenomenon and, in many cases, screening practices are difficult to implement among older people with dementia. The Caregiver Abuse Screen (CASE) is a useful tool which is administered to family caregivers for detecting their potential abusive behavior. Objectives. To validate the Italian version of the CASE tool in the context of family caregiving of ol

Socioeconomic Predictors of the Employment of Migrant Care Workers by Italian Families Assisting Older Alzheimer's Disease Patients : Evidence from the Up-Tech Study

Background: The availability of family caregivers of older people is decreasing in Italy as the number of migrant care workers (MCWs) hired by families increases. There is little evidence on the influence of socioeconomic factors in the employment of MCWs. Method: We analyzed baseline data from 438 older people with moderate Alzheimer's disease (AD), and their family caregivers enrolled in the Up-

Production of hyperpolarized [1,4-13C2]malate from [1,4-13C2]fumarate is a marker of cell necrosis and treatment response in tumors

Dynamic nuclear polarization of (13)C-labeled cell substrates has been shown to massively increase their sensitivity to detection in NMR experiments. The sensitivity gain is sufficiently large that if these polarized molecules are injected intravenously, their spatial distribution and subsequent conversion into other cell metabolites can be imaged. We have used this method to image the conversion

Health status and psychological distress among in-hospital cardiac arrest survivors in relation to gender

Aim To describe health status and psychological distress among in-hospital cardiac arrest (IHCA) survivors in relation to gender. Methods This national register study consists of data from follow-up registration of IHCA survivors 3–6 months post cardiac arrest (CA) in Sweden. A questionnaire was sent to the survivors, including measurements of health status (EQ-5D-5L) and psychological distress (H

Tissue-specific short chain fatty acid metabolism and slow metabolic recovery after ischemia from hyperpolarized NMR in vivo

Mechanistic details of mammalian metabolism in vivo and dynamic metabolic changes in intact organisms are difficult to monitor because of the lack of spatial, chemical, or temporal resolution when applying traditional analytical tools. These limitations can be addressed by sensitivity enhancement technology for fast in vivo NMR assays of enzymatic fluxes in tissues of interest. We apply this metho

Surface-sensitive X-ray diffraction across the pressure gap

In this chapter surface-sensitive X-ray diffraction is introduced as an important crystallographic tool for the investigation of surfaces and nanostructures under high pressure reaction conditions and elevated temperatures which are relevant for industrial catalysis. After the introduction surface-sensitive X-ray diffraction methods are briefly explained and specialized instrumentation developed f