255 research outputs found
Financiación de la edilicia pública y cálculo de los costes del material lapÃdeo: El caso del foro superior de Tarraco
Mouse embryo assay to evaluate polydimethylsiloxane (PDMS) embryo-toxicity
In vitro embryo culture to support In Vitro Fertilization (IVF) procedures is a well-established but still critical technique. In the last decade first attempts to use microfluidic devices in IVF have shown positive results, enabling to control the culture conditions and to preserve the quality of the embryos during their development. In this study we completed an industry standard mouse embryo assay (MEA) to exclude potential toxic effects of PDMS
Evaluation of friction enhancement through soft polymer micro-patterns in active capsule endoscopy
Capsule endoscopy is an emerging field in medical technology. Despite very promising
innovations, some critical issues are yet to be addressed, such as the management and possible
exploitation of the friction in the gastrointestinal environment in order to control capsule
locomotion more actively. This paper presents the fabrication and testing of bio-inspired
polymeric micro-patterns, which are arrays of cylindrical pillars fabricated via soft
lithography. The aim of the work is to develop structures that enhance the grip between an
artificial device and the intestinal tissue, without injuring the mucosa. In fact, the patterns are
intended to be mounted on microfabricated legs of a capsule robot that is able to move actively
in the gastrointestinal tract, thus improving the robot’s traction ability. The effect of
micro-patterned surfaces on the leg-slipping behaviour on colon walls was investigated by
considering both different pillar dimensions and the influence of tissue morphology. Several in
vitro tests on biological samples demonstrated that micro-patterns of pillars made from a soft
polymer with an aspect ratio close to 1 enhanced friction by 41.7% with regard to flat surfaces.
This work presents preliminary modelling of the friction and adhesion forces in the
gastrointestinal environment and some design guidelines for endoscopic devices
Assessment of the Fitbit Charge 2 for monitoring heart rate
Fitness trackers are devices or applications for monitoring and tracking fitness-related metrics such as distance walked or run, calorie consumption, quality of sleep and heart rate. Since accurate heart rate monitoring is essential in fitness training, the objective of this study was to assess the accuracy and precision of the Fitbit Charge 2 for measuring heart rate with respect to a gold standard electrocardiograph. Fifteen healthy participants were asked to ride a stationary bike for 10 minutes and their heart rate was simultaneously recorded from each device. Results showed that the Fitbit Charge 2 underestimates the heart rate. Although the mean bias in measuring heart rate was a modest -5.9 bpm (95% CI: -6.1 to -5.6 bpm), the limits of agreement, which indicate the precision of individual measurements, between the Fitbit Charge 2 and criterion measure were wide (+16.8 to -28.5 bpm) indicating that an individual heart rate measure could plausibly be underestimated by almost 30 bpm
Potential of Manuka Honey as a Natural Polyelectrolyte to Develop Biomimetic Nanostructured Meshes With Antimicrobial Properties
The use of antibiotics has been the cornerstone to prevent bacterial infections; however, the emergency of antibiotic-resistant bacteria is still an open challenge. This work aimed to develop a delivery system for treating soft tissue infections for: (1) reducing the released antimicrobial amount, preventing drug-related systemic side effects; (2) rediscovering the beneficial effects of naturally derived agents; and (3) preserving the substrate functional properties. For the first time, Manuka honey (MH) was proposed as polyelectrolyte within the layer-by-layer assembly. Biomimetic electrospun poly(εcaprolactone) meshes were treated via layer-by-layer assembly to obtain a multilayered nanocoating, consisting of MH as polyanion and poly-(allylamine-hydrochloride) as polycation. Physicochemical characterization demonstrated the successful nanocoating formation. Different cell lines (human immortalized and primary skin fibroblasts, and primary endothelial cells) confirmed positively the membranes cytocompatibility, while bacterial tests using Gram-negative and Gram-positive bacteria demonstrated that the antimicrobial MH activity was dependent on the concentration used and strains tested
Adhesion and proliferation of skeletal muscle cells on single layer poly(lactic acid) ultra-thin films
An increasing interest in bio-hybrid systems and cell-material interactions is evident in the last years. This leads towards the development of new nano-structured devices and the assessment of their biocompatibility. In the present study, the development of free-standing single layer poly(lactic acid) (PLA) ultra-thin films is described, together with the analysis of topography and roughness properties. The biocompatibility of the PLA films has been tested in vitro, by seeding C2C12 skeletal muscle cells, and thus assessing cells shape, density and viability after 24, 48 and 72 h. The results show that free-standing flexible PLA nanofilms represent a good matrix for C2C12 cells adhesion, spreading and proliferation. Early differentiation into myotubes is also allowed. The biocompatibility of the novel ultra-thin films as substrates for cell growth promotes their application in the fields of regenerative medicine, muscle tissue engineering, drug delivery, and-in general-in the field of bio-hybrid devices
Translational Roadmap for the Organs-on-a-Chip Industry toward Broad Adoption
Organs-on-a-Chip (OOAC) is a disruptive technology with widely recognized potential to change the efficiency, effectiveness, and costs of the drug discovery process; to advance insights into human biology; to enable clinical research where human trials are not feasible. However, further development is needed for the successful adoption and acceptance of this technology. Areas for improvement include technological maturity, more robust validation of translational and predictive in vivo-like biology, and requirements of tighter quality standards for commercial viability. In this review, we reported on the consensus around existing challenges and necessary performance benchmarks that are required toward the broader adoption of OOACs in the next five years, and we defined a potential roadmap for future translational development of OOAC technology. We provided a clear snapshot of the current developmental stage of OOAC commercialization, including existing platforms, ancillary technologies, and tools required for the use of OOAC devices, and analyze their technology readiness levels. Using data gathered from OOAC developers and end-users, we identified prevalent challenges faced by the community, strategic trends and requirements driving OOAC technology development, and existing technological bottlenecks that could be outsourced or leveraged by active collaborations with academia
A comprehensive view of the interstellar medium in a quasar host galaxy at z~6.4
Characterizing the physical conditions (density, temperature, ionization
state, metallicity, etc) of the interstellar medium is critical to our
understanding of the formation and evolution of galaxies. Here we present a
multi-line study of the interstellar medium in the host galaxy of a quasar at
z~6.4, i.e., when the universe was 840 Myr old. This galaxy is one of the most
active and massive objects emerging from the dark ages, and therefore
represents a benchmark for models of the early formation of massive galaxies.
We used the Atacama Large Millimeter Array to target an ensemble of tracers of
ionized, neutral, and molecular gas, namely the fine-structure lines: [OIII]
88m, [NII] 122m, [CII] 158m, and [CI] 370m and the
rotational transitions of CO(7-6), CO(15-14), CO(16-15), and CO(19-18); OH
163.1m and 163.4m; and HO 3(0,3)-2(1,2), 3(3,1)-4(0,4),
3(3,1)-3(2,2), 4(0,4)-3(1,3), 4(3,2)-4(2,3). All the targeted fine-structure
lines are detected, as are half of the targeted molecular transitions. By
combining the associated line luminosities, the constraints on the dust
temperature from the underlying continuum emission, and predictions from
photoionization models of the interstellar medium, we find that the ionized
phase accounts for about one third of the total gaseous mass budget, and is
responsible for half of the total [CII] emission. It is characterized by high
density (n~180 cm), typical of HII regions. The spectral energy
distribution of the photoionizing radiation is comparable to that emitted by
B-type stars. Star formation also appears to drive the excitation of the
molecular medium. We find marginal evidence for outflow-related shocks in the
dense molecular phase, but not in other gas phases. This study showcases the
power of multi-line investigations in unveiling the properties of the
star-forming medium in galaxies at cosmic dawn.Comment: 16 pages, 14 figures. Accepted for publication in A&
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