Interface nano-confined acoustic waves in polymeric surface phononic crystals

The impulsive acoustic dynamics of soft polymeric surface phononic crystals is investigated here in the hypersonic frequency range by near-IR time resolved optical diffraction. The acoustic response is analysed by means of wavelet spectral methods and finite element modeling. An unprecedented class of acoustic modes propagating within the polymer surface phononic crystal and confined within 100 nm of the nano-patterned interface is revealed. The present finding opens the path to an alternative paradigm for characterizing the mechanical properties of soft polymers at interfaces and for sensing schemes exploiting polymers as embedding materials

Prevention of congenital malformations and other adverse pregnancy outcomes with 4.0 mg of folic acid : community-based randomized clinical trial in Italy and the Netherlands

Background: In 2010 a Cochrane review confirmed that folic acid (FA) supplementation prevents the first- and second-time occurrence of neural tube defects (NTDs). At present some evidence from observational studies supports the hypothesis that FA supplementation can reduce the risk of all congenital malformations (CMs) or the risk of a specific and selected group of them, namely cardiac defects and oral clefts. Furthermore, the effects on the prevention of prematurity, foetal growth retardation and pre-eclampsia are unclear.Although the most common recommendation is to take 0.4 mg/day, the problem of the most appropriate dose of FA is still open.The aim of this project is to assess the effect a higher dose of peri-conceptional FA supplementation on reducing the occurrence of all CMs. Other aims include the promotion of pre-conceptional counselling, comparing rates of selected CMs, miscarriage, pre-eclampsia, preterm birth, small for gestational age, abruptio placentae.Methods/Design: This project is a joint effort by research groups in Italy and the Netherlands. Women of childbearing age, who intend to become pregnant within 12 months are eligible for the studies. Women are randomly assigned to receive 4 mg of FA (treatment in study) or 0.4 mg of FA (referent treatment) daily. Information on pregnancy outcomes are derived from women-and-physician information.We foresee to analyze the data considering all the adverse outcomes of pregnancy taken together in a global end point (e.g.: CMs, miscarriage, pre-eclampsia, preterm birth, small for gestational age). A total of about 1,000 pregnancies need to be evaluated to detect an absolute reduction of the frequency of 8%. Since the sample size needed for studying outcomes separately is large, this project also promotes an international prospective meta-analysis.Discussion: The rationale of these randomized clinical trials (RCTs) is the hypothesis that a higher intake of FA is related to a higher risk reduction of NTDs, other CMs and other adverse pregnancy outcomes. Our hope is that these trials will act as catalysers, and lead to other large RCTs studying the effects of this supplementation on CMs and other infant and maternal outcomes.Trial registration: Italian trial: ClinicalTrials.gov Identifier: NCT01244347.Dutch trial: Dutch Trial Register ID: NTR3161

Liquid motion control device for Lab-on-a-Chip (LOC) system of e.g. food analysis apparatus, has control unit with acoustic resonator that reflects surface acoustic wave (SAW) when quantity of liquid is present within acoustic resonator

The liquid motion control device has a control unit with an acoustic resonator (30) that is positioned in the path of SAW, and having a resonance cavity (30) between a pair of acoustic reflectors (31a,31b), which is arranged consecutively with respect to one another in the propagation direction of SAW. The acoustic resonator normally allows transmission of SAW having frequency equal to resonance frequency, and reflects SAW when quantity of liquid is present within the acoustic resonator

Interaction-free, automatic, on-chip fluid routing by surface acoustic waves

By exploiting the resonant coupling between a travelling wave and the stationary modes of a cavity, we present the first scheme for integrated automatic interaction-free surface acoustic wave routing of fluids. Our scheme opens the way to the implementation of logic gates based on instantaneous liquid distributio

Tubeless biochip for chemical stimulation of cells in closed-bioreactors: anti-cancer activity of the catechin–dextran conjugate

The most exciting promise of cell micro-bioreactors is their expected ability to reproduce specific aspects of physiological environments in vitro, singularly or in combination, and to perform advanced biological studies to unravel novel interaction mechanisms; but this challenge is formidable. Moreover, the use of microfluidics is limited by the difficulty to adapt standard tissue culture protocols to miniaturised biochips and by the need of bulky external equipment such as liquid pumping systems. Here, we introduce an original microfluidic gradient generator for culturing cells in closed microchambers, based on: (1) automatic cell valving, (2) hydrostatic-pressure pumping, and (3) on-chip liquid reservoirs. The biochip is designed to be fully compatible with standard biological procedures and to operate with no external control units or cumbersome ancillary components. Remarkably, the use of integrated liquid reservoirs prevents air bubble formation and associated channel clogging. We detail the rationale behind the fluidic design, simulate and measure the chip fluid-dynamics by finite element simulations and microflow velocimetry, respectively. We finally exploit our chip to study the kinetics of an anti-cancer molecule, the catechin-dextran conjugate, on HeLa cells, demonstrating a very fast action. We argue that the presented fluidic concept and architecture are not limited to the present realization, but can be easily applied to other chip geometries and adapted to a number of biological studies

Prevention of congenital malformations and other adverse pregnancy outcomes with 4.0\ua0mg of folic acid: community-based randomized clinical trial in Italy and the Netherlands

Background: In 2010 a Cochrane review confirmed that folic acid (FA) supplementation prevents the first-and second-time occurrence of neural tube defects (NTDs). At present some evidence from observational studies supports the hypothesis that FA supplementation can reduce the risk of all congenital malformations (CMs) or the risk of a specific and selected group of them, namely cardiac defects and oral clefts. Furthermore, the effects on the prevention of prematurity, foetal growth retardation and pre-eclampsia are unclear.Although the most common recommendation is to take 0.4 mg/day, the problem of the most appropriate dose of FA is still open.The aim of this project is to assess the effect a higher dose of peri-conceptional FA supplementation on reducing the occurrence of all CMs. Other aims include the promotion of pre-conceptional counselling, comparing rates of selected CMs, miscarriage, pre-eclampsia, preterm birth, small for gestational age, abruptio placentae.Methods/Design: This project is a joint effort by research groups in Italy and the Netherlands. Women of childbearing age, who intend to become pregnant within 12 months are eligible for the studies. Women are randomly assigned to receive 4 mg of FA (treatment in study) or 0.4 mg of FA (referent treatment) daily. Information on pregnancy outcomes are derived from women-and-physician information.We foresee to analyze the data considering all the adverse outcomes of pregnancy taken together in a global end point (e.g.: CMs, miscarriage, pre-eclampsia, preterm birth, small for gestational age). A total of about 1,000 pregnancies need to be evaluated to detect an absolute reduction of the frequency of 8%. Since the sample size needed for studying outcomes separately is large, this project also promotes an international prospective meta-analysis.Discussion: The rationale of these randomized clinical trials (RCTs) is the hypothesis that a higher intake of FA is related to a higher risk reduction of NTDs, other CMs and other adverse pregnancy outcomes. Our hope is that these trials will act as catalysers, and lead to other large RCTs studying the effects of this supplementation on CMs and other infant and maternal outcomes