Green synthesis of vanillin: Pervaporation and dialysis for process intensification in a membrane reactor

In the present work, two different membrane processes (pervaporation and dialysis) are compared in view of their utilization in a membrane reactor, where vanillin, which is probably the most important aroma of the food industry, is synthesized in a green and sustainable way. The utilized precursor (ferulic acid, which is possibly a natural product from agricultural wastes) is partially oxidized (photocatalytically or biologically) and the product is continuously recovered from the reacting solution by the membrane process to avoid its degradation. It is observed that pervaporation is much more selective towards vanillin than dialysis, but the permeate flux of dialysis is much higher. Furthermore, dialysis can work also at lower temperatures and can be used to continuously restore the consumed substrate into the reacting mixture. A mathematical model of the integrated process (reaction combined with membrane separation) reproduces quite satisfactorily the experimental results and can be used for the analysis and the design of the process

The dry stone in Tírig. Raimundo Puig, mestre paredador

L’arquitectura de pedra seca té, sovint, protagonistes amb nom i cognoms. Són els paredadors, uns professionals que dedicaren la seua vida a la construcció de diferents elements amb aquesta tècnica. Raimundo Puig és un bon exemple i, a més a més, va treballar a Tírig però també a altres municipis de les comarques del Maestrat i els Ports. La seua història és la representació d’una forma de vida que, òbviament, queda reflectida en la seua obra, les barraques, els bancals, els pous i altres construccions que la seua saviesa ens va llegar. Aquest treball vol recuperar l’obra d’un paredador, caracteritzar les seues construccions que presenten algunes particularitats, com el morro de llebre, i posar en valor el nostre patrimoni rural.The dry stone architecture often is not anonymous because we find the paredadors, professionals who have dedicated their lives to the construction of various elements using this technique. Raimundo Puig is a good example. He worked in Tírig but also in other towns in the Maestrat and Els Ports (Castelló). His story is the depiction of a lifestyle that obviously reflected in his work, the barraques, the terraces and other structures bequeathed us his wisdom. This work aims to recover the work of a paredador, to characterize their structures and show peculiarities, as the morro de llebre, and to value our rural heritage

Combinatorial optimization based recommender systems.

Recommender systems exploit a set of established user preferences to predict topics or products that a new user might like [2]. Recommender systems have become an important research area in the field of information retrieval. Many approaches have been developed in recent years and the interest is very high. However, despite all the efforts, recommender systems are still in need of further development and more advanced recommendation modelling methods, as these systems must take into account additional requirements on user preferences, such as geographic search and social networking. This fact, in particular, implies that the recommendation must be much more “personalized” than it used to be. In this paper, we describe the recommender system used in the “DisMoiOu”(“TellMeWhere” in French) on-line service (http://dismoiou.fr), which provides the user with advice on places that may be of interest to him/her; the definition of “interest” in this context is personalized taking into account the geographical position of the user (for example when the service is used with portable phones such as the Apple iPhone), his/her past ratings, and the ratings of his/her neighbourhood in a known social network. Using the accepted terminology [6], DisMoiOu is mainly a Collaborative Filtering System (CFS): it employs opinions collected from similar users to suggest likely places. By contrast with existing recommender systems, ours puts together the use of a graph theoretical model [4] and that of combinatorial optimization methods [1]. Broadly speaking, we encode known relations between users and places and users and other users by means of weighted graphs. We then define essential components of the system by means of combinatorial optimization problems on a reformulation of these graphs, which are finally used to derive a ranking on the recommendations associated to pairs (user,place). Preliminary computational results on the three classical evaluation parameters for recommender systems (accuracy, recall, precision [3]) show that our system performs well with respect to accuracy and recall, but precision results need to be improved

Cyanomatrix and Cyanofilm

Cyanobacteria are diverse in their habitats, structure, and metabolism that can grow as unicellular or long filaments and secreting high molecular mass polymers (extracellular polymer substances, EPS), which can either be released into the surrounding environment or remain attached to the cell surface. Four different cyanobacterial environmental samples (soil crust, microbial mats, pond water and marine bloom) were studied to compare between the cyanobacteria species that grow and form cyanomatrix and cyanofilms in those environmental habitats using light and scanning electron microscope (SEM). Diatoms were also detected with cyanobacteria at microbial mats and pond water samples. All samples had variable concentrations and compositions of extracellular matrix and biofilm. Microscopic observation and analyses also revealed complex network of filamentous cyanobacteria and extracellular polymer secretions, which binds and traps particles of soil and minerals

Hypolithic cyanobacteria colonization of quartz at South Desert

Hypolithic microbial communities (found underneath rocks) were encountered in the southern desert of Qatar where quartz rocks are ubiquitous and are a substrate for hypoliths. These hypoliths thrive where extreme temperature, moisture stress and high light intensity limit the occurrence of higher plants and animal life. A small-scale ecological survey indicated that 80% of the quartz rocks in the area were colonized by green hypolithic microbial communities dominated by colonization of cyanobacteria. Using light and electron microscopic analyses; the cyanobacterial community structure of hypoliths was shown to be dominated by cyanobacteria affiliated to the genera Chroococcidiopsis, Aphanothece, Pleurocapsa, Oscillatoria, Lyngbya, Leptolyngbya, Phormidium and Scytonema).Scopu

Integrating modelling of maintenance policies within a stochastic hybrid automaton framework of dynamic reliability

The dependability assessment is a crucial activity for determining the availability, safety and maintainability of a system and establishing the best mitigation measures to prevent serious flaws and process interruptions. One of the most promising methodologies for the analysis of complex systems is Dynamic Reliability (also known as DPRA) with models that define explicitly the interactions between components and variables. Among the mathematical techniques of DPRA, Stochastic Hybrid Automaton (SHA) has been used to model systems characterized by continuous and discrete variables. Recently, a DPRA-oriented SHA modelling formalism, known as Stochastic Hybrid Fault Tree Automaton (SHyFTA), has been formalized together with a software library (SHyFTOO) that simplifies the resolution of complex models. At the state of the art, SHyFTOO allows analyzing the dependability of multistate repairable systems characterized by a reactive maintenance policy. Exploiting the flexibility of SHyFTA, this paper aims to extend the tools’ functionalities to other well-known maintenance policies. To achieve this goal, the main features of the preventive, risk-based and condition-based maintenance policies will be analyzed and used to design a software model to integrate into the SHyFTOO. Finally, a case study to test and compare the results of the different maintenance policies will be illustrated

Microfluidic cartridge with integrated array of amorphous silicon photosensors for chemiluminescence detection of viral DNA

Portable and simple analytical devices based on microfluidics with chemiluminescence detection are particularly attractive for point-of-care applications, offering high detectability and specificity in a simple and miniaturized analytical format. Particularly relevant for infectious disease diagnosis is the ability to sensitively and specifically detect target nucleic acid sequences in biological fluids. To reach the goal of real-life applications for such devices, however, several technological challenges related to full device integration are still to be solved, one key aspect regarding on-chip integration of the chemiluminescence signal detection device. Nowadays, the most promising approach is on-chip integration of thin-film photosensors. We recently proposed a portable cartridge with microwells aligned with an array of hydrogenated amorphous silicon (a-Si:H) photosensors, reaching attomole level limits of detection for different chemiluminescence model reactions. Herein, we explore its applicability and performance for multiplex and quantitative detection of viral DNA. In particular, the cartridge was modified to accommodate microfluidic channels and, upon immobilization of three oligonucleotide probes in different positions along each channel, each specific for a genotype of Parvovirus B19, viral nucleic acid sequences were captured and detected. With this system, taking advantage of oligoprobes specificity, chemiluminescence detectability, and photosensor sensitivity, accurate quantification of target analytes down to 70 pmol L-1 was obtained for each B19 DNA genotype, with high specificity and multiplexing ability. Results confirm the good detection capabilities and assay applicability of the proposed system, prompting the development of innovative portable analytical devices with enhanced sensitivity and multiplexed capabilities

Functional Lipids in Autoimmune Inflammatory Diseases

Lipids are apolar small molecules known not only as components of cell membranes but also, in recent literature, as modulators of different biological functions. Herein, we focused on the bioactive lipids that can influence the immune responses and inflammatory processes regulating vascular hyperreactivity, pain, leukocyte trafficking, and clearance. In the case of excessive pro-inflammatory lipid activity, these lipids also contribute to the transition from acute to chronic inflammation. Based on their biochemical function, these lipids can be divided into different families, including eicosanoids, specialized pro-resolving mediators, lysoglycerophospholipids, sphingolipids, and endocannabinoids. These bioactive lipids are involved in all phases of the inflammatory process and the pathophysiology of different chronic autoimmune diseases such as rheumatoid arthritis, multiple sclerosis, type-1 diabetes, and systemic lupus erythematosus

Ecophysiology of Wild Plants and Conservation Perspectives in the State of Qatar

© 2013 Yasseen and Al-Thani, licensee InTech. This is an open access chapter distributed under the term