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Mass printing processes are the key technology to produce mass products to the point of one-disposable. Carbon nanotube (CNT) based structures were prepared by flexographic printing using multi-walled carbon nanotube (MWCNT) dispersions in water. The carbon nanotubes were applied to a textile substrate made of polyester and polyamide microfilaments and to both-side coated paper to produce electrically conductive layers that can be used, for example, as heating elements. Carbon nanotube layers with sheet resistivity ranging from 0.12 to 3.00 kΩ/sq were obtained. The ratio of radiation power PS (determined according to the Stefan-Boltzmann law) of the printed layers to the electrical power spent, represents the efficiency of the system. The samples on textile substrate with a surface temperature of 169°C have an efficiency of 25%, the paper samples with a surface temperature of 93 °C have an efficiency of about 15 %.

This research was in collaboration with the IBB Institute for Biotechnology and Bioengineering Centre of biological Engineering University of Minho, Campus de Gualtar, Braga, Portugal.

Bioethanol can be produced from several different biomass feedstocks: sucrose rich feedstocks (e.g. sugar-cane), starchy materials (e.g. corn grain), and lignocellulosic biomass. This last category, including biomass such as corn stover and wheat straw, woody residues from forest thinning and paper, is promising especially in those countries with limited lands availability. In fact, residues are often widely available and do not compete with food production in terms of land destination. The process converting the biomass biopolymers to fermentable sugars is called hydrolysis. There are two major categories of methods employed. The first and older method uses acids as catalysts, while the second uses enzymes called cellulases. Feedstock pretreatment has been recognized as a necessary upstream process to remove lignin and enhance the porosity of the lignocellulosic materials prior to the enzymatic process (Zhu & Pan, 2010; Kumar et al., 2009). Cellulases are proteins that have been conventionally divided into three major groups: endoglucanase, which attacks low cristallinity regions in the cellulose fibers by endoaction, creating free chain-ends; exoglucanases or cellobiohydrolases which hydrolyze the 1, 4glycocidyl linkages to form cellobiose; and β-glucosidase which converts cellooligosaccharides and disaccharide cellobiose into glucose residues. In addition to the three major groups of cellulose enzymes, there are also a number of other enzymes that attack hemicelluloses, such as glucoronide, acetylesterase, xylanase, β-xylosidase, galactomannase and glucomannase. These enzymes work together synergistically to attack cellulose and hemicellulose. Cellulases are produced by various bacteria and fungi that can have cellulolytic mechanisms significantly different. The use of enzymes in the hydrolysis of cellulose is more effective than the use of inorganic catalysts, because enzymes are highly specific and can work at mild process conditions. In spite of these advantages, the use of enzymes in industrial processes is still limited by

Flax (Linum usitatissimum) is an important crop plant that is widely distributed in the Mediterranean and temperate climate zones. It has great significance for industry as a valuable source of oil and fibres. A unique feature of flax is the possibility of whole plant exploitation with almost no waste products. For this reason, flax has quite significant potential for biotechnological application. To increase the valuable qualities of flax products, the flax genome has been genetically modified, with the specific aims to improve the plant’s pathogen resistance, taste and nutritional properties, and to produce pharmaceuticals and other compounds. In this chapter, we describe the plant characteristics that show the biochemical and industrial importance of flax oil and fibres and their various possible applications and the relevant genetic modifications. Since ancient times, flax has been known to be a source of oil and fibres, and it has been cultivated as a dual-purpose plant for a long time. Nowadays, it is a multi-purpose plant and its exploitation is not restricted to the production of linen fibre and oil. Actually, whole plant exploitation is possible, which justifies the name given to it by Linnaeus: L. usitatissimum, meaning “useful flax”. There is a wide range of possible applications of flax (Fig.1). The long fibres are used in the textile industry, and the short fibres in paper production, isolation materials and biocomposite production. The wooden shives released during flax scutching can serve as an energy source. Flax seeds also have many important applications, and due to its high nutritional value, it is used in the food, pharmaceutical and health care industries. The seedcake, which is rich in antioxidants, is used in the pharmaceutical and cosmetic industries. The development of molecular biology emerged as an important tool for the genetic modification of plants, and enabled the improvement of many different features of wild type plants. These modifications broadened the range of practical applications for flax, making the plant more valuable and more significant for the innovative biotechnological industry.

A novel approach to the inspection of nanoparticle habit was proposed in our previous papers. This approach is based on a joint analysis of two scanning electron microscopy (SEM) images corresponding to different convergences of illuminating electron beams. However, increasing convergence worsens an image as the result of spherical aberration. Therefore, for the first time in this paper we describe in detail a new approach which is an alternative to the method of two convergences. It is based on the use of two defocusings which are identical in size, but opposite in signs, thereby. simplifying the demands of SEM.

Yield and productivity of many crop species depend on successful reproductive develop‐ ment to produce seeds or fruits for human nutrition. Plants determine the right time to flower based on environmental cues (day length, temperature) and angiosperms have evolved a plethora of mechanisms to adapt flowering to specific environmental condi‐ tions. Despite these adaptation mechanisms, fertilisation and seed production remain subject to the reigning weather conditions before and during flowering. To fertilise the immobile female gametes inside the ovule, the male gametophytes need to be dispersed in a hostile environment. In crop plants, unexpected inclement weather conditions during male gametophyte development and pollen dispersal are often associated with dramatic yield losses. Molecular and physiological studies are gradually making progress in iden‐ tifying genes and processes that control various aspects of pollen development, but the many intricacies involved in environmental control of pollen development and – in par‐ ticular – regulation of male fertility remain poorly understood. The aim of this paper is to draw attention to the enormous amount of complexity and biodiversity that exist in an‐ giosperm male gametophyte development. A better understanding of the strategies that exist in adapting pollen production and fertility to environmental challenges may ulti‐ mately benefit improvement of abiotic stress tolerance in major food crops.

The main objective of this paper was the selection of promising bacterial strains to be used as potential tools to remove phenols in olive mill wastewater (OMW) or in other food wastes. Therefore, 12 OMW samples were analyzed and 119 isolates were collected. After a preliminary screening on a medium containing vanillic and cinnamic acids, three isolates were selected to evaluate their viability in presence of different compounds (cinnamic, vanillic and caffeic acids, rutin, tyrosol and oleuropein) and a possible bioremediation effect. The isolates generally survived with phenols added and exerted a significant bioremediation activity in some samples (reduction of phenols by 20%). The last step was focused on the evaluation of the combined effects of pH, cinnamic and vanillic acids on the viability of a selected isolate (13M); the combination of the acids exerted a strong effect on the target, but alkaline pH played a protective role.

This paper presents a study of adsorption and vibrational features of folic acid, using surface-enhanced Raman scattering (SERS). A gold-capped silicon nanopillar (Au NP) with a height of 600 nm and a width of 120 nm was utilized to study the vibrational features of FA molecules adsorbed on the nanopillars within the high electromagnetic field areas. The adsorption behaviour of folic acid and the band assignment of the main vibrations together with the optimized geometry of folic acid and folic acid in the presence of a cluster of 10 gold atoms were assessed using the density functional theory (B3LYP(6–31G(d))) and the scalar relativistic effective core potential with a double-zeta basis set (LANL2DZ). The vibrations obtained from the solid-state folic acid and the folic acid on a gold cluster were in accordance with those observed experimentally. The analysis of the main vibrations indicated that the interaction of folic acid with the Au NP occurred primarily through the nitrogen atoms, from their pteridine ring. Finally, the obtained adsorption isotherm for folic acid was deduced from the analysis of the SERS spectra and it followed a negative cooperative binding model.

Ti-6Al-4V alloy with TiO2 coating is the most commonly selected material to construct an aortic heart valve. Wear resistance is the main mechanical property to be evaluated for this purpose. In this paper, the wear resistance of TiO2 thin films obtained by anodic oxidation of Ti-6Al-4V is evaluated. Anodic oxidation was performed at 20 V to 70 V with a H2SO4 1 M electrolyte. The samples were thermally treated at 500°C for 1 h, and crystalline phases of TiO2 were obtained. The wear was performed in a ball-on-flat recip‐ rocating machine with a range of loads from 1 gf to 4 gf and times between 60 s and 1200 s, using a diamond sphere as counterface. The counterface oscillates at 0.5 Hz and 4 mm in amplitude. The wear is measured using a profilometer and is calculated as the worn volume. The wear resistance of the coated samples is larger than the substrate, and increases with thickness and with crystalline coating. Fil: Vera, Maria Laura. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Nordeste. Instituto de Materiales de Misiones; Argentina Fil: Rosenberger, Mario Roberto. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Nordeste. Instituto de Materiales de Misiones; Argentina Fil: Schvezov, Carlos Enrique. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Nordeste. Instituto de Materiales de Misiones; Argentina Fil: Ares, Alicia Esther. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnológico Nordeste. Instituto de Materiales de Misiones; Argentina

This paper describes an easy and time-saving strategy for the fabrication of heterogeneous nanotubular arrays of TiO2-CdS (TCHNTAs) on transparent conductive glass (FTO) and their photoelectrochemical properties. The use of transparent FTO instead of opaque Ti substrate allows incident light from the substrate side. The anodized TiO2 nanotubular arrays were firstly detached from Ti substrate by anodization under a high voltage of 120 V and then transferred to FTO substrate using TiO2 (P25) paste as a binder, followed by sensitization with CdS nanoparticles. After optimizing the deposition cycles of CdS nanoparticles, the TCHNTAs on FTO substrate demonstrated an enhanced photocurrent density in the Na2S/Na2SO3 electrolyte under front-side illumination from the FTO side, which improved by ∼ 21% when compared with the photocurrent density under back-side illumination from the TiO2-CdS side. This improvement in photoelectrochemical properties can be ascribed to the reduced charge recombination on the interface between the TiO2 nanotubes and the CdS nanoparticles under front-side illumination. Our strategy for nanotubular transfer on transparent substrate may extend the applications of TiO2 nanotubular arrays into other fields, such as dye-sensitized solar cells, photochromism and photocatalysis.

Layer-by-layer self-assembly is an approach to develop an ultrathin film on solid support by alternate exposure to positive and negative species with spontaneous deposition of the oppositely charged ions. This paper summarizes various approaches used for fabrication of layer-by-layer self-assembly as well as their utility to produce various devices. The layer-by-layer technique is basically used for formation of multilayer films. A variety of nanomaterials use it for the modification of films to enhance their resultant durability as well as strength. Studies have shown that many different types of materials can be used for fabrication of multilayers. Recently the layer-by-layer self-assembly technique has also been used for fabrication of gas sensors, hydrogen sensors and solar-based cells. Various methods, such as spin deposition, calcinations, and dry-transfer printing are being used for fabrication of thin films. In this review, the author summarizes the various interesting properties as well as fabrication strategies of layer-by-layer self-assembly.

In this work, we report on the electroplating of ultrafine and uniform magnesium (Mg) films on copper (Cu) and carbon nanotube (CNT) paper substrates. By controlling the process parameters and utilizing the pulsed deposition method, the average grain size of Mg was reduced to nano-dimensions. Surface pretreatment of the substrates by depositing a seed layer was found to be an efficient strategy for reducing the energy barrier for nucleation, thus improving nucleation density and the uniformity of deposited coatings. This work provides important guidance for the fabrication of smooth nanostructured Mg films on different substrates for a wide variety of applications.

In chemical and medical research, recent methods combine the tools of nanotechnology, chemistry and biology in a way that introduces the most modern processes to current medical practice. The main blood plasma proteins – albumin and globulin and their amino acid sequences, are carriers of important information about human health. In this paper we employed silver nanostructured surfaces prepared by electrodeposition. Consequently, electrochemical deposition is introduced as a convenient, fast and cost-effective method for the preparation of metallic nanostructures with required morphology. Silver nanostructured surfaces were applied as the templates for Surface Enhanced Raman Spectroscopy (SERS) of albumin and globulin in the role of model analytes. We also studied the effect of a working electrode polishing process on electrodeposition and identification of proteins. The aqueous solutions of albumin and globulin were applied onto these Ag nanostructured substrates separately. An analytical signal enhancement factor of 3.6×102 was achieved for a band with a Raman shift of 2104cm-1 for globulin deposited onto silver nanostructured film on unpolished stainless steel substrate. The detection limit was 400μg/mL. Plasma or serum could present a preferable material for noninvasive cancer disease diagnosis using the SERS method.

This paper presents a discrete-time decentralized control scheme for trajectory tracking of a two degrees of freedom (DOF) robot manipulator. A high order neural network (HONN) is used to approximate a decentralized control law designed by the backstepping technique as applied to a block strict feedback form (BSFF). The weights for each neural network are adapted online by an extended Kalman filter training algorithm. The motion for each joint is controlled independently using only local angular position and velocity measurements. The stability analysis for the closed-loop system via the Lyapunov approach is included. Finally, the real-time results show the feasibility of the proposed control scheme robot manipulator.

In this paper we present a rapid and simple one-pot method to obtain gold nanoparticles functionalized with folic acid using a photochemistry method. The bioconjugate folic acid-gold nanoparticle was generated in one step using a photo-reduction method, mixing hydrogen tetrachloroaurate with folic acid in different ratios and varying the illumination time of a mercury lamp (λ = 255 nm). Scanning electron microscopy showed a particle size of around 40–50nm and dynamic light scattering exhibited that the zeta potential varies from −41 to −50mV with different illumination times. Storage in the dark at 4°C prolongs the stability of folic acid-gold nanoparticle suspensions to up to 26 days. Ultraviolet visible and Fourier transform infrared spectroscopy showed a surface plasmon band of around 534nm and fluorescence spectroscopy exhibited a quenching effect on gold nanoparticles in the fluorescence emission of folic acid and thus confirmed the conjugation of folic acid to the surface of gold nanoparticles. In this study we demonstrate the use of a photochemistry method to obtain folic acid-gold nanoparticles in a simple and rapid way without the use of surfactants and long reaction times. The photochemical synthesis of FA-AuNPs opens new perspectives for creating novel functional nanomaterials for biomedical applications.

Biotechnology is becoming more popular and well identified as a mainline industry. Students have shown greater interest in learning the techniques. As a discipline, biotechnology has led to new advancements in many areas. Criminal investigation has changed dramatically thanks to DNA fingerprinting. Significant advances in forensic medicine, anthropology and wildlife management have been noticed in the last few years. Biotechnology has brought out hundreds of medical diagnostic tests that keep the blood safe from infectious diseases such as HIV and also aid detection of other conditions early enough to be successfully treated. Medical kits for diabetes, blood cholesterol and home pregnancy tests are also biotechnology diagnostic products. Industrial biotech applications have led to cleaner processes that produce less waste and use less energy and water in such industrial sectors as chemicals, pulp and paper, textiles, food, energy, and metals and minerals. Laundry detergents produced in many countries contain biotechnology-based enzymes making them nature friendly and safer. Agricultural biotechnology benefits farmers, consumers and the environment by increasing yields and farm income, decreasing pesticide applications and improving soil and water quality, and providing healthful foods for consumers. Biotechnology has created more than 200 new therapies and vaccines, including products to treat cancer, diabetes, HIV/ AIDS and autoimmune disorders.

In this paper, we report on multiphysics full-wave techniques in the frequency (energy)-domain and the time-domain, aimed at the investigation of the combined electromagnetic-coherent transport problem in carbon based on nano-structured materials and devices, e.g., graphene nanoribbons. The frequency-domain approach is introduced in order to describe a Poisson/Schrödinger system in a quasi static framework. An example of the self-consistent solution of laterally coupled graphene nanoribbons is shown. The time-domain approach deals with the solution of the combined Maxwell/Schrödinger system of equations. The propagation of a charge wavepacket is reported, showing the effect of the self-generated electromagnetic field that affects the dynamics of the charge wavepacket.

In this paper, the analysis of charge injection from metal to a contacted graphene nanoribbon (GNR) is developed by means of a scattering matrix approach. The charge transport, described by the Schrödinger equation in the 2D domain of the GNRs, is solved, together with the 3D Poisson equation for the potential distribution. Varying the work function of the metal contacted to the GNR, alters the so-called “metal doping”, i.e., the amount of charge in the GNR. As easily expected, this in turn affects the I-V characteristic of a GNR channel across two electrodes. Interesting effects appear as the contribution of GNR sub-band is considered and included in the self-consistent calculation.

The electrical properties of electrodeposited zinc-copper-telluride (ZnCuTe) nanowires embedded in polycarbonate track-etch membrane (Whatman) having pore-diameters of 200, 100 and 50nm have been studied and reported in this paper. Scanning electron microscopy (SEM) confirmed the formation of the nanowires of uniform diameter equal to the diameter of the templates used. I-V measurements at room temperature (303K) reveal that the nanowires of diameter 200, 100 and 50nm have linear and ohmic characteristics. Higher electron transport was observed in larger diameter nanowires compared to smaller ones which may be attributing to size effect. The temperature-dependent electrical transport measurements over a temperature range 308–423K reveal that the temperature dependence of electrical conductivity increases with increasing temperature and decreases as the nanowires size decreases. The study reveals that ZnCuTe nanowires have negative temperature coefficient of resistance (TCR).

In the last few years biotechnology has been making its way into many areas of industry. Biotechnology is the application of life organisms and their components into industrial processes and products (Warke & Chandratre, 2003). The biological systems that have traditionally been used are organisms such as yeasts, fungi and bacteria. The progress of industrial biotechnology in the last twenty years, especially in molecular biology, protein engineering and fermentation technology, enhanced the development of new uses of enzymes in the food industry, the use spread into the areas of detergents, paper and leather industry, natural polymer modification, organic chemical synthesis, diagnostics ... The use of enzymes experienced an increase in the textile industry as well. Amylases were the first enzymes applied in textile processing to remove starch-based sizes from fabrics after weaving. Later proteases were introduced into detergent formulations to remove organic protein-based stains from textile garments and cellulases to remove fibrillation in multiple washes. Further applications have been found for these enzymes to produce the aged look of denim and other garments (Gubitz & Cavaco-Paulo, 2001). Today enzymes offer a wide variety of alternative, environment and fibre friendly procedures which are replacing or improving the existing classical technological procedures. Cellulases, proteases, amylases, catalases, pectinases, peroxidases and lactases are the enzymes that can replace aggressive chemicals (Cavaco-Paulo & Gubitz, 2003). Researchers have tried to apply enzymes into every step of textile wet processing, ranging from pretreatment, bleaching, dyeing to finishing, and even effluent treatment. Some applications have become well established and routine, while some have not yet been successfully industrialized due to technical or cost constraints. A famous example is bioscouring or biopreparation, a process that specifically targets noncellulosic impurities within the textile fabrics, with pectinases (Lu, 2005).