Surface Energy and Lewis Acid-base Characteristics of Lignocellulosic Fibers upon Modification by Chemical Vapor Deposition of Trichloromethylsilane: An Inverse Gas Chromatography Study

Supplemental data for this article can be accessed on the publisher’s website at http:// dx.doi.org/10.1080/02773813.2018.1454961The surface of a thermomechanical pulp (TMP), containing 26 wt% of lignin, was modified by silanization with trichloromethylsilane (TCMS) via chemical vapor deposition, and thoroughly analyzed for its physicochemical properties by inverse gas chromatography (attenuated total reflection-Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy being used as complementary tools). For a 2-min TCMS-treated TMP, a decrease of the dispersive component of the surface energy from 38 to 14 mJ m−2 (at 40°C), and, at the same time, an increase of the Lewis acidic and Lewis basic characters were found. The surface of this sample, modified in a high extent, was similar to that of a bleached kraft pulp (<0.1 wt% of lignin) subjected to the same silanization process, which is suggested as being due, in both cases, to the formation of a methyl-silica coating on the fiber’s surface. The new silanized fibers obtained from cheap TMP can be used for the production of a new generation of biocomposites with a variety of matrices

Investigation of the Effects of Hydrodynamic and Parasitic Electrostatic Forces on the Dynamics of a High Aspect Ratio MEMS Accelerometer

AbstractWe present the results of an extensive characterization of physical and electrostatic effects influencing the dynamical behavior of a micro-electromechanical (MEMS) accelerometer based on commercial technology. A similar device has been utilized recently to demonstrate the effect of Casimir and other nano-scale interactions on the pull-in distance [Ardito et. al., Microelectron. Reliab., 52 (2012) 271]. In the present work, we focus on the influence of pressure, plate separation, and electric surface potentials on the spectral mechanical response. We finally find evidence for the presence of non-viscous damping due to compressibility of the ambient gas, and demonstrate a strong dependence of the sensitivity on the parameters of the operating point

Medical needs related to the endoscopic technology and colonoscopy for colorectal cancer diagnosis

Background. The high incidence and mortality rate of colorectal cancer require new technologies to improve its early diagnosis. This study aims at extracting the medical needs related to the endoscopic technology and the colonoscopy procedure currently used for colorectal cancer diagnosis, essential for designing these demanded technologies. Methods. Semi-structured interviews and an online survey were used. Results. Six endoscopists were interviewed and 103 were surveyed, obtaining the demanded needs that can be divided into: a) clinical needs, for better polyp detection and classification (especially flat polyps), location, size, margins and penetration depth; b) computer-aided diagnosis (CAD) system needs, for additional visual information supporting polyp characterization and diagnosis; and c) operational/physical needs, related to limitations of image quality, colon lighting, flexibility of the endoscope tip, and even poor bowel preparation.This work is part of the PICCOLO project, which has received funding from the European Union’s Horizon 2020 research and innovation Programme under grant agreement No. 732111. GR18199, funded by “Consejería de Economía, Ciencia y Agenda Digital, Junta de Extremadura” and co-funded by European Union (ERDF “A way to make Europe”). The funding bodies did not play any roles in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript

Three axis vector magnet set-up for cryogenic scanning probe microscopy

We describe a three axis vector magnet system for cryogenic scanning probe microscopy measurements. We discuss the magnet support system and the power supply, consisting of a compact three way 100 A current source. We obtain tilted magnetic fields in all directions with maximum value of 5T along z-axis and of 1.2T for XY-plane magnetic fields. We describe a scanning tunneling microscopy-spectroscopy (STM-STS) set-up, operating in a dilution refrigerator, which includes a new high voltage ultralow noise piezodrive electronics and discuss the noise level due to vibrations. STM images and STS maps show atomic resolution and the tilted vortex lattice at 150 mK in the superconductor β-Bi2Pd. We observe a strongly elongated hexagonal lattice, which corresponds to the projection of the tilted hexagonal vortex lattice on the surface. We also discuss Magnetic Force Microscopy images in a variable temperature insertThis work was supported by Convocatoria Doctorados en el Exterior 568-2012 COLCIENCIAS, the Spanish MINECO (FIS2011-23488, MAT2011-27470-C02-02, CSD2009-00013), by the Comunidad de Madrid through program Nanofrontmag-CM (S2013/MIT-2850) and by Marie-Curie actions under the project FP7-PEOPLE-2013- CIG-618321. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement No. 604391 Graphene Flagship. We also acknowledge Banco Santander, COST MP1201. J.A. and C.M. acknowledge the FPI (BES- 2012-058600) and Juan de la Cierva (JCI-2011-08815) programs, respectivel

Fanconi anemia cells with unrepaired DNA damage activate components of the checkpoint recovery process

International audienceBACKGROUND:The FA/BRCA pathway repairs DNA interstrand crosslinks. Mutations in this pathway cause Fanconi anemia (FA), a chromosome instability syndrome with bone marrow failure and cancer predisposition. Upon DNA damage, normal and FA cells inhibit the cell cycle progression, until the G2/M checkpoint is turned off by the checkpoint recovery, which becomes activated when the DNA damage has been repaired. Interestingly, highly damaged FA cells seem to override the G2/M checkpoint. In this study we explored with a Boolean network model and key experiments whether checkpoint recovery activation occurs in FA cells with extensive unrepaired DNA damage.METHODS:We performed synchronous/asynchronous simulations of the FA/BRCA pathway Boolean network model. FA-A and normal lymphoblastoid cell lines were used to study checkpoint and checkpoint recovery activation after DNA damage induction. The experimental approach included flow cytometry cell cycle analysis, cell division tracking, chromosome aberration analysis and gene expression analysis through qRT-PCR and western blot.RESULTS:Computational simulations suggested that in FA mutants checkpoint recovery activity inhibits the checkpoint components despite unrepaired DNA damage, a behavior that we did not observed in wild-type simulations. This result implies that FA cells would eventually reenter the cell cycle after a DNA damage induced G2/M checkpoint arrest, but before the damage has been fixed. We observed that FA-A cells activate the G2/M checkpoint and arrest in G2 phase, but eventually reach mitosis and divide with unrepaired DNA damage, thus resolving the initial checkpoint arrest. Based on our model result we look for ectopic activity of checkpoint recovery components. We found that checkpoint recovery components, such as PLK1, are expressed to a similar extent as normal undamaged cells do, even though FA-A cells harbor highly damaged DNA.CONCLUSIONS:Our results show that FA cells, despite extensive DNA damage, do not loss the capacity to express the transcriptional and protein components of checkpoint recovery that might eventually allow their division with unrepaired DNA damage. This might allow cell survival but increases the genomic instability inherent to FA individuals and promotes cancer

Frequency and predictors of thrombus inside the guiding catheter during interventional procedures: an optical coherence tomography study

Optical coherence tomography (OCT) is able to identify thrombus. We detect the frequency of thrombus inside the guiding catheter by OCT and its relationship with clinical and procedural factors. We screened 77 patients who underwent OCT pullbacks. Only patients with visible guiding catheter were finally included (35) and divided into thrombus (21) or no-thrombus group (14). Patients within thrombus group were mostly males (100 vs. 71 %, p = 0.05), with acute coronary syndrome (76 vs. 36 %, p = 0.02) and received more frequently percutaneous coronary intervention (86 vs. 43 %, p = 0.01) as compared to other group. A second dose of heparin was more frequently administered in thrombus than in other group (86 vs. 50 %, p = 0.01). Time between first heparin administration and OCT pullback (41[28–57] vs. 20 min [10–32], p = 0.001), time elapsed from second heparin administration and OCT pullback (29 [19–48] vs. 16 min [12–22], p = 0.002) and total procedural time (47 [36–69] vs. 31 min [26–39], p = 0.005) were longer in thrombus compared to other group. At multivariate analysis, total procedural time and time between first heparin administration and OCT pullback were only predictors of intra-catheter thrombus (HR 0.6 [0.3–0.9], p = 0.03 and HR 1.9 [1.1–3.2], p = 0.02, respectively). Thrombus inside guiding catheter may be a frequent finding in long interventional procedure. Future studies are warranted to determine its clinical impact