THERMAL PROCESS EVALUATION OF RETORTABLE POUCHES FILLED WITH CONDUCTION HEATED FOOD

Two models using the finite element technique (FE) and another using an analytical solution to solve the 3‐dimensional heat conduction equation for a finite plate were built. FE models were built considering the actual pouch shape and retort temperature profile. Chi‐square and regression lines were obtained for each set of temperatures generated by the models against experimental data. A mass average sterilizing value of 9.9 min was estimated when a critical point sterilizing value was at 8.7 min using the 3‐Dimensional FE model. Close agreement was found among the three models for heating phase. Using actual retort temperature profile made FE models more accurate than the one using analytical solution, especially for cooling phase.     

Circulating Monocyte Subsets and Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR), as an alternative to open heart surgery, has revolutionized the treatment of severe aortic valve stenosis (AVS), the most common valvular disorder in the elderly. AVS is now considered a form of atherosclerosis and, like the latter, partly of inflammatory origin. Patients with high-grade AVS have a highly disturbed blood flow associated with high levels of shear stress. The immediate reopening of the valve during TAVR leads to a sudden restoration of a normal blood flow hemodynamic. Despite its good prognosis for patients, TAVR remains associated with bleeding or thrombotic postprocedural complications, involving mechanisms that are still poorly understood. Many studies report the close link between blood coagulation and inflammation, termed thromboinflammation, including monocytes as a major actor. The TAVR procedure represents a unique opportunity to study the influence of shear stress on human monocytes, key mediators of inflammation and hemostasis processes. The purpose of this study was to conduct a review of the literature to provide a comprehensive overview of the impact of TAVR on monocyte phenotype and subset repartition and the association of these parameters with the clinical outcomes of patients with severe AVS who underwent TAVR.     

Halogenated Ti3C2 MXenes Prepared by Microwave Molten Salt for Hg0 Photo-Oxidation

Ti₃C₂ MXenes with different halogen modifications are prepared rapidly and efficiently by microwave molten salt method, and the MXene surface functional group modification is successfully achieved to address the problems of low purity, complex functional groups, and uncontrollable energy band structure of MXenes obtained by traditional liquid phase etching. Among them, the modification of the iodine (I) functional group onto the surface of Ti₃C₂ changes the energy band structure and band gap, resulting in easier photoexcitation and more photogenerated carriers. The increased Fermi energy is closer to the conduction band, the decreased surface work function weakens the electron confinement ability. The photogenerated carriers can migrate to the surface of the material more easily with extended lifetime, so the activity of the catalyst is improved. Further, for gaseous monomeric mercury (Hg⁰) photo-oxidative removal, Ti₃C₂-I₂ exhibits 85.5% efficiency of Hg⁰ photo-oxidative removal under visible light. Based on the experimental characterization and density functional theory calculations, a mechanism for the photo-oxidative removal of Hg° from Ti₃C₂-I₂ MXene is proposed, which provides a valuable strategy for studying Ti₃C₂ MXenes in the field of photocatalysis.     

Hybrid film of chemically modified graphene and vapor-phase-polymerized PEDOT for electronic nose applications

A hybrid of graphene and conducting polymer holds great potential as the active materials for high performance chemical sensor application. In this work, a thin hybrid film of reduced graphene oxide (RG-O) and poly(3,4-ethylenedioxythiophene) (PEDOT) was fabricated by means of vapor phase polymerization and explored as active material for chemical sensors. The chemical sensors based on hybrid film of RG-O and PEDOT are capable of detecting electrical signals caused by the absorption of trace levels of different analyte vapors with high sensitivity, selectivity and fast response.     

Ultrafast Doppler imaging of blood flow dynamics in the myocardium

Imaging intramyocardial vascular flows in real-time could strongly help to achieve better diagnostic of cardiovascular diseases. To date, no standard imaging modality allows describing accurately myocardial blood flow dynamics with good spatial and temporal resolution. We recently introduced a novel ultrasonic Doppler imaging technique based on compounded plane waves transmissions at ultrafast frame rate. The high sensitivity of this ultrafast Doppler technique permits to image the intramyocardial blood flow and its dynamics. A dedicated demodulation-filtering process is implemented to compensate for the large tissue velocity of the myocardium during the cardiac cycle. A signed power Doppler processing provides the discrimination between arterial and venous flows. Experiments were performed in vivo in a large animal open chest model ( N = 5 sheep) using a conventional ultrasonic probe placed at the surface of the heart. Results show the capability of the technique to image intramyocardial vascular flows in normal physiological conditions with good spatial (200 μm) and temporal resolution (10 ms). Flow dynamics over the cardiac cycle were investigated and the imaging method demonstrated a phase opposition of flow waveforms between arterial and venous flows. Finally, ultrafast Doppler combined with tissue motion compensation was found able to reveal vascular flow disruption in ischemic regions during occlusion of the main diagonal coronary artery.     

Correlation study between standard plate count and flow cytometry for determination of raw milk total bacterial count

Milk samples were collected in the dry season ( n =  155) and in the rainy season ( n =  68) to establish a correlation between electronic flow cytometry and standard plate count for the determination of total bacterial count of raw milk. Results were expressed in individual bacterial count (ibc) and colony forming unit (cfu) for electronic flow cytometry (Bactocount) and standard plate count, respectively. The accuracy of Bactocount, denoted by the residual standard deviation ( s ( y,x )), was 0.309 log cfu/mL. The predictive interval of estimated values was broad and it is suggested that total bacterial count should be expressed in ibc without transformation to cfu.     

TEXTURAL CHANGES IN VEGETABLES DURING THERMAL PROCESSING. II. EFFECTS of ACIDIFICATION and SELECTED PRETREATMENTS ON TEXTURE of TURNIPS

The effect of different preprocessing treatments on the softening of vegetable tissues during acidification of turnips at different temperatures was studied. Texture was characterized by the maximum load force in a puncture test. the different preprocessing treatments considered were blanching alone and coupled with vacuum infusion, freezing/thawing and calcium chloride addition. Samples were acidified at different constant temperatures: 20, 50, 70 and 90C. Results were obtained by comparing the softening occurring for all samples and for non-preprocessed turnips. It was found that for low temperature processing the final result was mainly due to the effect of the preprocessing itself on the turnip texture while for high temperature processing the effect of the preprocessing on the tissues sensitivity to the processing was more important. Blanching alone caused greater softening when processing at 70C but lead to a firmer product when coupled with calcium chloride addition or vacuum infusion for processing at 70 and 90C.     

Vertically aligned carbon nanotube‐based composite: Elaboration and monitoring of the nanotubes alignment

We present the different elaboration steps of a composite formed of carbon nanotubes (CNT) carpet embedded in an epoxy polymer. Detailed characterization at each step of the elaboration process is performed. The good alignment of CNT in as‐grown carpets is kept all along the elaboration process of the composite, as it is measured at both macro and microscopic scales by X‐ray scattering. We also ensured by X‐ray fluorescence measurements that the iron‐based catalyst particles used for the synthesis were removed from the carpet after a high temperature post‐annealing treatment. These measurements give valuable information for further applications involving unidirectional nanotube composites and membranes, where CNT alignment is a key parameter. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39730.