Skin Barrier Function and the Microbiome

Human skin is the largest organ and serves as the first line of defense against environmental factors. The human microbiota is defined as the total microbial community that coexists in the human body, while the microbiome refers to the collective genome of these microorganisms. Skin microbes do not simply reside on the skin but interact with the skin in a variety of ways, significantly affecting the skin barrier function. Here, we discuss recent insights into the symbiotic relationships between the microbiome and the skin barrier in physical, chemical, and innate/adaptive immunological ways. We discuss the gut-skin axis that affects skin barrier function. Finally, we examine the effects of microbiome dysbiosis on skin barrier function and the role of these effects in inflammatory skin diseases, such as acne, atopic dermatitis, and psoriasis. Microbiome cosmetics can help restore skin barrier function and improve these diseases.     

Evaluation of a cognitive-behavioral intervention for adolescents.

The aim of this study was to evaluate the effect of a cognitive- behavioral, biofeedback-assisted intervention to impart skills for coping with stressful encounters in a nonclinical adolescent population. Israeli Arab and Israeli Jewish participants completed pre- and postintervention questionnaires assessing state anxiety, test anxiety, behavior symptoms, hostility, and self-esteem. Electrodermal activity was recorded using biofeedback. From pre- to postintervention, scores of state anxiety, test anxiety, behavior symptoms, and self-esteem, but not hostility, changed significantly in the intervention group as compared with the control group. A significant Group × School effect was evident for state and test anxiety and behavior problems, indicative of higher reductions in the Arab group. The cognitive-behavioral program proved an effective preventive intervention for adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

ECG compression method based on adaptive quantization of main wavelet packet subbands

In this study, a new compression algorithm for ECG signal is proposed based on selecting important subbands of wavelet packet transform (WPT) and applying subband-dependent quantization algorithm. To this end, first WPT was applied on ECG signal and then more important subbands are selected according to their Shannon entropy. In the next step, content-based quantization and denoising method are applied to the coefficients of the selected subbands. Finally, arithmetic coding is employed to produce compressed data. The performance of the proposed compression method is evaluated using compression rate (CR), percentage root-mean-square difference (PRD) as signal distortion, and wavelet energy-based diagnostic distortion (WEDD) as diagnostic distortion measures on MIT-BIH Arrhythmia database. The average CR of the proposed method is 29.1, its average PRD is <2.9 % and WEDD is <3.2 %. These results demonstrated that the proposed method has a good performance compared to the state-of-the-art compression algorithms.     

Evaluation of specific absorbed fractions from internal photon sources in ORNL analytical adult phantom

To design a diagnostic or therapeutic irradiation programme, there is a need to estimate the absorbed dose. In this investigation, specific absorbed fractions (SAFs) were calculated based on Cristy and Eckerman's analytical adult phantom, by MCNP4C Monte Carlo code. SAFs were estimated with uncertainty <3%, for about 600 source organ-target organ pairs at 12 photon energies (these data are available at http://www.um.ac.ir/~mirihakim). Then these results were compared with Cristy and Eckerman's, which were based on direct Monte Carlo, reciprocity principle and point source kernel methods. Also, agreements and disagreements between them for different states were discussed.     

An investigation on effect of geometrical parameters on spray cone angle and droplet size distribution of a two-fluid atomizer

A visual study is conducted to determine the effect of geometrical parameters of a two-fluid atomizer on its spray cone angle. The liquid (water) jets exit from six peripheral inclined orifices and are introduced to a high speed gas (air) stream in the gravitational direction. Using a high speed imaging system, the spray cone angle has been determined in constant operational conditions, i.e., Reynolds and Weber numbers for different nozzle geometries. Also, the droplet sizes (Sauter mean diameter) and their distributions have been determined using Malvern Master Sizer x. The investigated geometrical parameters are the liquid jet diameter, liquid port angle and the length of the gas-liquid mixing chamber. The results show that among these parameters, the liquid jet diameter has a significant effect on spray cone angle. In addition, an empirical correlation has been obtained to predict the spray cone angle of the present two-fluid atomizer in terms of nozzle geometries.     

Static Stability of Liquid Bridges Between Matrix Blocks of a Gas Invaded Zone of Naturally Fractured Reservoirs

A large portion of oil and gas reservoirs in the world are located in naturally fractured reservoirs. Despite such importunity, the production mechanisms of these reservoirs are not completely well defined. Gas–oil gravity drainage that takes place in the gas-invaded zone of this type of reservoirs is one instance of such a weakness. The density difference between gas-filled fractures in contact with oil-saturated matrix blocks brings the oil out of the matrix blocks into the fracture. The drained oil can reach the production well through two different paths: continues fracture network and block-to-block path. These two different paths require different approaches to modeling of gravity drainage. Single-block approaches are used when drained oil only travels through the fracture network, which totally formulated before. But when oil prefers to travel through the matrix blocks, continuum approaches such as Darcy's law may not work in their basic forms any more. Liquid bridges and film that form in the horizontal fracture between matrix blocks usually transfer the wetting phase across the fracture. Stability condition and duration of stability can help better understanding of gravity drainage in stacks of blocks. In this article, the stability of liquid bridges between the matrix blocks studied and a minimum length of stability is predicated. The results show that this stable length of liquid bridges formed between adjacent matrix blocks is 2r₀π, which is a function of the pore throat. This critical length can be used in modeling of capillary continuity and wetting phase transfer across matrix blocks.     

Sand control screen selection for cased dual-annulus gas offshore wells based on scaled laboratory tests

This paper assessed and ranked several alternatives to control sand production in a well recompletion effort of offshore gas wells that have experienced massive sanding. The aim was to select an appropriate thru-liner sand control system to increase well productivity. Four different screen types were evaluated, including a wire-wrapped screen (WWS), slotted liner (SL), punched screen (PS), and a new multi-layer open cell matrix polymer (OCMP) filter resembling gravel-pack. The performance of screens regarding sand production and plugging was evaluated using a sand retention testing facility featuring a custom-made device that mimics the unique well completion configuration. Further, a novel testing setup was constructed to assess the erosion potential of screens subject to high-velocity gas and sand flow. All assessments were conducted under the representative actual well conditions. Laboratory tests indicate the superior performance of the OCMP filter compared to the other three options. Even though SL, WWS, and PS performed similarly in sanding, the WWS posed a higher erosion risk, with PS following in second place. The plugging tendency of the WWS was the least among all the options, whereas the PS had the highest tendency. Despite this, the WWS's sanding performance is expected to decline due to its vulnerability to erosion. Overall, the testing results indicated that the OCMP filter provides a promising solution to the issue of sand production in the gas wells being evaluated. However, the interaction of the OCMP filter with potential treatment chemicals in the wells should be tested before it can be used.     

Trichroic infrared analysis of the strain-induced structural changes in the PA6 layer of PA6/PE multilayer films under biaxial drawing

This work deals with the structural evolution under biaxial drawing of PA6/tie/PE multilayer films as a function of composition. The occurrence of plastic instabilities in the PA6 layer in the multilayers is strongly reduced with respect to the PA6 monolayer film and the maximum biaxial drawability of PA6 is considerably improved with increasing PE layer thickness. Quantitative evaluation by trichroic infrared analysis of the various crystal forms of the PA6 component shows that the strain-induced β-α crystalline phase transition is delayed in the multilayers, i.e. equivalent level of phase transformation is reached at higher strains. Similar phenomenon is observed regarding the orientation within the film plane of the PA6 chains in the strain-induced α-crystals, i.e. equivalent chain orientation is reached at higher strains in the multilayers. The deformation synergism between the PA6 and PE layers is discussed in terms of benefiting effect from the PE layer that prevents plastic instabilities and promotes homogeneous deformation accompanied with orthotropic extension of the chains in the PA6 layer. This is the driving force to the delay of the detrimental β-α phase transition of PA6, the mechanically anisotropic α-crystals being highly crack-prone in contrast to the ductile isotropic β-crystals. Film rupture is shown to occur when the PA6 strain-induced α-crystals reach a constant content of about 10%, irrespective of film composition and draw temperature in the range 80-110 °C. This kind of critical phenomenon is assigned to a percolation process of the crack-prone α-crystals.     

MOSAICA: A web-2.0 based system for the preservation and presentation of cultural heritage

The question of how to present cultural heritage resources in a way that attracts potential users is becoming important in our ever-changing world. This paper describes MOSAICA system – a web 2.0-based toolbox, dedicated for the preservation and presentation of cultural heritage. This paper also describes an evaluation study that examined MOSAICA system’s usability and social impact. Online questionnaires and semi-structured interviews were administered among users from Israel, France, and Poland. Findings indicated positive views related to MOSAICA’s usage in terms of knowledge gain, ease of use, and attractiveness. Findings also indicated that learning about the stories, customs, and traditions of diverse cultures, via hypertext narratives, may enhance positive dispositions toward open-mindedness, in general, and non-judgmental views, in specific. MOSAICA system provides a generic framework for users, of any culture and religion, to actively engage in preserving their heritage via activities such as investigation, exploration, and storytelling.