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The purpose of this paper is the approach of a mathematical model dedicated to planning the consecutive days off of a company’s employees. Companies must find a flexible work schedule between employees, always considering the satisfaction of work tasks as well as guaranteeing consecutive days off. The analysis is based on solving a quadratic programming problem with binary variables. The proposed method uses the properties of the circulant symmetric matrix in the researched model, which allows the transformation of the considered problems into an equivalent separable non-convex optimization problem. A practical continuous convex relaxation approach is proposed. DC Algorithm is used to solve relaxed problems. A solved numerical example is presented.

Binary quadratic programming is a classical combinatorial optimization problem that has many real-world applications. This paper presents a method for solving the quadratic programming problem with circulant matrix by reformulating and relaxing it into a separable optimization problem. The proposed method determines local suboptimal solutions. To solve the relaxing problem, the DCA algorithm it is proposed to calculate the solutions, in the general case, only local suboptimal.

This paper presents a state of the art in field of intelligent user interfaces, which are the main elements that make the interaction between humans and machines in the most efficient, natural, effective way. As an interdisciplinary product, the design of user interfaces represents the combination of models from disciplines like software engineering, artificial intelligence, human-computer interaction and other disciplines (sociology, psychology, etc.). In the process of design and operation of production systems, an important factor is its responsiveness and the ability to have integrated the capacity to change over time and functionally. To achieve a high level of structural configuration and feasibility, a production system must have a compatible interface.

Anthocyanins are water-soluble pigments characterized by various intense colors found in fruits and vegetables. Scientific studies have shown growing evidence to support their health benefits. Therefore, estimating the anthocyanin content in food is essential to identify the ideal analytical method. Moreover, due to the instability of plant anthocyanins, it is important to select and optimize their extraction, separation and qualitative and quantitative analysis, steps that are indispensable and important in their study. The present article reviews the latest procedures for extracting anthocyanins from various food matrices and analytical methods for their quantification. Therefore, various forms of preliminary treatments of samples for anthocyanin extraction, extraction procedures for various fruits, vegetables and cereals, purification of samples and quantification of anthocyanins are highlighted and evaluated. Using ultrasound-assisted extraction (UAE) might be effective for anthocyanin extraction and the Amberlite XAD-7HP method is the most effective for purifying anthocyanins. Combining the liquid chromatography (LC) method with electrospray ionization (ESI) and mass spectrometry (MS) or quadrupole time-of-flight (QTOF) with mass spectrometry (MS) better quantifies the anthocyanins in the food complex samples. Therefore, the extraction and separation of anthocyanins and their qualitative and quantitative analyses are essential steps in their research. As a result, the study concentrates on a detailed characterization of various qualitative and quantitative analytical methodologies, while briefly describing the main anthocyanin extraction processes.

We report the first successful green synthesis route for organic transistors based on para-aminobenzoic acid (PABA) grafted to ferrite nanoparticles, at room temperature. The obtained core–shell nanoparticles (NCS) have been investigated by DLS, FT-IR, SEM, TEM. Both average hydrodynamic diameter and zeta potential of synthesized PABA-NCS nanoparticles has been identified, indicating a good stability of this nano-compound. SEM analysis proved a heterogeneous structured material with quasi-uniform granular formations in size, while TEM revealed a ferrite core of 20 nm. The measurements of output characteristics in the saturation regime and transfer characteristics at negative gate voltages have proved that an organic transistor based on PABA-NCS has been accomplished. The current increasing over a negative threshold voltage demonstrated an accumulation channel onset in the PABA-NCS thin film. This is a final argument for the p-type behavior of the PABA-NCS film.

A new nanostructured solid phase synthesis magnetic support consisting of core-shell type magnetic nanoparticles based on magnetite, para-aminobenzoic acid (PABA) and secondary silica shell were synthesized by coprecipitation method and characterized. An newly designed organic linker with an ending hydroxyl group inspired by HMBA linker (4-hydroxy methyl benzamide) widely employed in classical peptide solid phase synthesis was obtained from 1,4-dimethylolbenzene and gamma-isocyanatopropyltriethoxysilane and was grafted on the surface in order to be used for the nanophase synthesis of peptides. Three reaction stages, yielding a tripeptide sequence, using n-terminal protected amino acids and the principle of solid phase synthesis through the Fmoc strategy were performed, in order to prove the effectiveness of the nanophase peptide synthesis. The MS analysis confirmed the success of the tripeptide synthesis, recommending the new nanostructured system as a solid support in the solid phase synthesis of peptides. The intermediate and final materials were analysed by advanced characterization methods (SEM, TEM, BET, X-ray diffraction, magnetic properties, DLS, FT-IR, NMR for organic intermediates characterization, TGA and LC-MS).

In this paper we describe the synthesis of a core-shell material using yttrium superconducting ceramic material (YBCO) and cobalt ferrite nanoparticles in order to obtain a nanostructured material with magnetic properties. The advantages of such material aim the selective deposition of nanofilms oriented in magnetic fields. To obtain this core-shell material, the solutions of the nitrates were first obtained by dissolving the salts in demineralised water. The suspension with cobalt ferrite nanoparticles was obtained by co-precipitation method. To obtain YBa2Cu3O7-�- coated magnetic nanoparticles by autocombustion reaction the solutions of nitrates and citric acid were used. The ratio of the metal ions: Y:Ba:Cu was 1:2:3, and between the oxidant and the reducing agent was used a citrate / nitrate mass ratio equal with 0.7. The final material was analyzed by X-ray diffraction (XRD), electronic scanning microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), high resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer (VSM).

Therapeutic benefits of phytochemicals are widespread, but the association of natural lipophilic and hydrophilic compounds in the same nanostructured delivery system represents a challenge that was not considered up to present. This work aimed to evaluate the effects of two plant-derived oils rich in ω-3 (rosehip oil – Ro) and ω-6 (black caraway oil – Bco) on the synthesis of marigold extract (ME) and azelaic acid (AzA) co-loaded nanostructured lipid carriers (NLC) and to determine its in vitro and in vivo anti-inflammatory action. The lipid core and surfactant shell guaranteed a high encapsulation efficiency of both water soluble-AzA and lipid soluble-ME (93% entrapment for carotenoids and 83% for AzA). A high degree of biocompatibility in the concentration range of 5–400 μg/mL NLC-ME-AzA for 72 h of treatment was determined (i.e. at 400 μg/mL the L929 cells displayed a proliferative effect with a cell viability of 110%). The co-presence of ME and AzA in the same NLC was accompanied by a reduced expression of inflammatory IL-6 and IL-1β cytokines, as evidenced by ELISA method. The in vivo plestismometric method showed that paw edema was significantly reduced for 3 h following NLC-ME-AzA hydrogel treatment (0.006 mg ME and 26.2 mg AAz) in rats challenged with carrageenan.

The applications of nano-core materials with doped external shell by para-amino-benzoic acid to construct an organic transistor are presented. The transistor adopts a typical configuration of an organic transistor, but using point contacts as a pseudo-MOS transistor. The device is prepared by Ag deposition on a glass substrate, followed by dip coating depositions for the organic materials. The measured static characteristics revealed acceptor behavior of the active film, indicating the accumulation onset at negative gate voltage. At higher voltages, some oscillations are recorded in this device with silver gate.

The aim of this work is to select the proper electrode materials for organic thin film transistors (OTFT). The electrodes are crucial both for Pentacene-OTFT or transistors with other semiconductors without toxic precursors. In this scope, the paper is developed on two directions: (i) simulation of OTFT, starting from a fabricated Pentacene transistor, able to match the simulated characteristics with the experimental characteristics and (ii) experimental tests on an organic transistor with silver electrodes for source and drain and para-amino-benzoic acid coupled to ferrite nano-core-shell as active organic layer. The experimental material is silver for electrodes. Further improvements are expected by gold and other materials with optimal workfunction.

This paper is focused on biosensors that detect catabolists and anabolists of some living cells coupled with Ion Selective Electrodes within Transistors. The global biosensor can be treated as an electronic device, which input stimulus is the analyte concentration that is converted in electric voltage or current. Because the dependence of the output reply – electrical current – versus the analyte concentration is a non-linear function on large work domain, the Nonlinear Electrical Conduction Theorem (NECT) can be applied here for the sensitivity domain optimization. Claimed in 1993 by Adrian Rusu, the NECT theorem can find the thresholds points of any non-linear device or sensor. Some experimental picked points of two bacterial biosensors reported in the bioscience literature were analyzed in this paper by NECT. A suitable model that obeys to the Non – Linear Electrical Conduction Theorem is developed.

The growing scientific interest in exploitation of vegetable bioactives has raised a number of questions regarding their imminent presence in pharmaceutical formulations. This study intends to demonstrate that a dual combination between vegetable oil (e.g. thistle oil, safflower oil, sea buckthorn oil) and a carrot extract represents an optimal approach to formulate safe carrier systems that manifest cell regeneration effect and promising antioxidant and anti-inflammatory activity. Inclusion of both natural actives into lipid carriers imparted a strong negative charge on the nanocarrier surface (up to -45mV) and displayed average sizes of 70nm to 140nm. The entrapment efficiency of carrot extract into nanostructured carriers ranged between 78.3 and 88.3%. The in vitro release study has demonstrated that the entrapment of the extract represents a viable way for an equilibrated release of carotenoids. Besides the excellent antioxidant properties (e.g. scavenging up to 98% of the free oxygen radicals), the results of cellular integrity (e.g. cell viability of 133%) recommend these nanocarriers based on dual carrot extract-bioactive oil as a promising trend for the treatment of certain disorders in which oxidative stress plays a prominent role. In addition, the lipid nanocarriers based on safflower oil and sea buckthorn oil demonstrated an anti-inflammatory effect on LPS induced THP-1 macrophages, by inhibiting the secretion of two pro-inflammatory cytokines, IL-6 and TNF-α.

Phytochemicals are priceless sources of bioactive compounds with multiple health benefices. The main objective of the current investigation was to develop nanostructured herbal formulations conditioned as appropriate hydrogel (HG) conferring an enhanced transdermal absorption of bioactive compounds from selective extracts and vegetable oils. The direct impact of research is represented by the identification of prototype products which manifest an improved therapeutic response, by means of cumulative antioxidant, anti-inflammatory and anti-acne actions, without causing any side health effects. The combinatorial effect of Carrot Extract (CE) and Marigold Extract (ME) – Nanostructured Lipid Carriers (NLC) based on rosehip oil or black cumin oils was accompanied by a high biocompatibility and a significant ability to capture both short- and long-life free radicals. HG-NLC-ME-CE has been shown to be an efficient carrier with a differentiated potential for in vitro release of the two active principles, e.g. it delayed the release of carotenoids while the hydrophilic active (azelaic acid, AA) was faster released. The HG-NLC efficacy in skin inflammation treatment (demonstrated by in vitro and in vivo tests) revealed a reduced expression of inflammatory cytokines (IL-1β and TNF-α), more pronounced in the case of TNF-α. Moreover, a superior in vivo anti-inflammatory effect of HG-based NLC-CE/ME-AA as compared to that obtained for a commercial product was detected, i.e. after 3 h of HG-NLC treatment, a significant reduction of rat paw edema was quantified. In pre-clinical studies, the quantification of the hydration and elasticity effects in the viable epidermis provided the evidence of the high potential of developed prototypes, suitable for implementation in the market area. The degree of skin hydration and skin elasticity were remarkable enhanced after topical application of developed prototypes, a hydration effect up to 74% being determined and a skin elasticity reaching 90%. The knowledge acquired from this investigation could be utilized by the cosmetic industry to design novel topical products with improved quality and health benefices, endowed with antioxidant, anti-inflammatory and anti-acne actions and with desired hydration and elasticity profiles, in order to achieve better therapeutic efficacy and no drug toxicity.

As first aim, a start Pentacene-Organic Thin Film Transistor - OTFT - is simulated to capture the static characteristics and to find the matching parameters with the experimental set-up. The current vectors validate the main conduction way and the OTFT functionality. In a second stage, the basic technology of an alternative polymer grafted on nanomaterial synthesis, is depicted. The Fe304 core-shell nanoparticles are assembled by an external shell of paraaminobenzoic acid (PABA). The final scope will be OTFT construction by these green technologies. The first step: the Fe 3 O 4 /PAbathin films synthesis and characterization, is successfully performed.

This paper presents a novel type of technology involved in the Thin Film Transistors (TFT) fabrication, using ferrite-Nano-Core-Shell-multilayer (NCS) materials. In a first stage, the applied technology of the nanomaterial synthesis is depicted. Primary core-shell np's ferrite nano-particles (Fe304) is processed by self-assembling of an external shell with organic compound (PABA - para-aminobenzoic acid). Dynamic Light Scattering characterization reveals a hydrodynamic width of 70.9nm and a high zeta potential of 51.6 mV, indicating high stability of the technology. The material applications in TFT is in progress. Therefore, some Atlas simulations capture the static characteristics and superior performances for transistor with nano-core-shell material. Either NCS or Poly-Silicon, the current vectors flow thru a TFT device proves the main conduction way and the device functionality.

New route synthesis of YBCO / graphene composite material is described in the present work. The oxide mixture and graphene were obtained separately and then mixed together by ball milling in the mass ratio graphene: YBCO = 1: 100. The oxide mixture was prepared by modified auto combustion reaction starting from stoichiometric amounts of yttrium acetate and barium and copper nitrates without any other organic compound addition. Graphene materials were prepared by reducing GO (i.e. oxidation of graphite powder by a modified Hummers method) with hidrazine sulphate. The final material resulted by applying the ball-milling method was investigated by XRD, SEM, Raman and HRTEM.

The study describes an ideal approach to increase the co-encapsulation of two water and lipid-soluble drugs in the same delivery system. The main purpose is represented by the exploitation of oil fractions isolated from amaranth seeds for the development of squalene-based nanocarriers able for a dual release of one antitumor drug, pemetrexed and one bio-flavonoid, hesperidin. The co-encapsulated nanocarriers presented unique nanoassembly morphology and showed excellent stability against aggregation. A delimited repartition of both actives, mainly in oily nanoconfinements of lipid nanocariers has been indicated by scanning calorimetry. The entrapment efficiency study revealed a great encapsulation effect with values reaching 94% for hesperidin and 89% for pemetrexed. These values are associated with a high ability of squalene-nanocarriers to capture free radicals. The greatest antioxidant activity was determined for nanocarriers that co-encapsulate 1.4% drugs, e.g., 97.3 and 98.2%. In vitro co-release tests demonstrated that pemetrexed and hesperidin were gradually released despite of their different lipophilicity. The most concentrated squalene fraction assures a slower release of both actives. The cumulative results showed that the applied strategy is a promising approach to improve the performance of medical treatments used to prevent and treat diseases associated with tumor and oxidative stress.

Fresh beef slices were marinated by immersion in marinades based on dry red wine, lime-tree honey, salt, spices and seasoning plants such as thyme (Thymus vulgaris), marjoram (Majorana hortensis), garlic (Allium sativum) and horseradish (Armoracia rusticana). Once marinated, meat pieces were vacuum packed and stored at 4C for 12 days. Experimental data indicated that marination of bovine Biceps femoris muscle in wine-based marinades with spices and seasoning plants addition significantly decreased (P 0.05) on L*, a* and b* but significant on Mb (myoglobin), MMb (metmyoglobin) and MbO2 (oxymyoglobin) percentages. Electrophoretic pattern of muscle proteins showed reduction of molecular weight and relative density (%) of some protein fractions for marinated samples compared with the control. Practical Applications Meat quality can be defined as a combination of sensory characteristics and technological aspects, such as color, water-holding capacity, cooking losses and texture. Marinades based on dry red wine, lime-tree honey, salt, spices and seasoning plants might be used as a marinating agent for improving the tenderness of tough meat and decreasing cooking losses with no effect on meat color. It can be easily applied at household and industrial levels as an easy technique to improve meat tenderness. Improvement in tenderness will be of great value to both consumers and meat processors.

Fresh beef slices were marinated by immersion in marinades based on dry red wine, lime-tree honey, salt, spices and seasoning plants as thyme ( Thymus vulgaris ), marjoram ( Majorana hortensis ), garlic ( Allium sativum ) and horseradish ( Armoracia rusticana ). Control samples were prepared without marinating treatment but packed and stored in the same conditions as marinated samples. After marination, meat pieces were packed under vacuum and stored at 4°C for 12 days. The combined effects of spices and marination on beef tenderness were evaluated by monitoring pH evolution, the protein and collagen degree of hydrolysis and tenderness. Experimental data indicated that marination weaken beef meat structure, producing improvement of functional properties of adult beef. Marinades use lead for an increase in the protein nitrogen fraction, free amino acids and hydroxyproline contents in boiled beef cuts. A significant increase in tenderness by hardness measurement was observed in the samples marinated and boiled, as compared with the control. Key words : Acidic marination, beef meat, marinating time, meat hardness, pH.

Reduction of nitro substituted 2,5-diaryloxazoles with hydrazine hydrate and Raney nickel affords in good yield 2,5-diaryloxazoles having amino group(s) on the aryl ring(s) . The reaction of 2,4,6-trisubstituted pyrylium perchlorates with mono- and diamino-2,5-diaryloxazoles yields new mono- and bispyridinium perchlorates with a central 2,5-diaryloxazole group. Their electronic, 13C NMR and 1H NMR spectra are presented and discussed.

A modified ferrite co-precipitation synthesis was used to obtain core–shell Fe3O4/salicylic acid magnetic nanoparticles (Sa-MNP) with well-dispersed aqueous solution properties. The newly developed iron oxide nanoparticles properties were investigated with X-ray diffraction, Fourier transform infrared spectrometry, transmission electron microscopy, and laser light scattering for their characteristic establishment. The resulting Sa-MNPs have spherical morphology, homogenous size distribution around 60 nm (35 nm FWHM), and a 67 mV Zeta potential value (15.5 mV STDV). In vivo biocompatibility and intravascular behavior of the 60 nm diameter size range synthesized nanoparticles were evaluated on chick chorioallantoic membrane model. The results show a reversible and good controlled intravascular accumulation under static magnetic field, a low risk of embolisation with nanoparticle aggregates detached from venous intravascular nanoblocked areas, a persistent blocking of the arterioles and dependent capillaries network, a good circulating life time and biocompatibility. The beneficial effects of salicylic acid (SA) and in vivo demonstrated capacity of Sa-MNPs to cutoff regional vascular supply under static magnetic field control suggest a possible biomedical application of these MNPs in targeted cancer therapy through magnetic controlled blood flow nanoblocking mechanism.

Flow-vacuum pyrolysis of the title fused tetrazole derivatives (II) and (V), resp., provides stable N-cyanoheterocycles in good yield.

Reduction of nitro substituted 2,5-diaryloxazoles with hydrazine hydrate and Raney nickel affords in good yield 2,5-diaryloxazoles having amino group(s) on the aryl ring(s) . The reaction of 2,4,6-trisubstituted pyrylium perchlorates with mono- and diamino-2,5-diaryloxazoles yields new mono- and bispyridinium perchlorates with a central 2,5-diaryloxazole group. Their electronic, 13 C NMR and 1 H NMR spectra are presented and discussed.

The increased social and economic importance of ready–made food production, together with the complexity of production technology, processing, handling and acceptance of these fragile and perishable products requires extensive knowledge of their physical properties. Viscoelastic properties play an important role in the handling and quality attributes of creams.Our study was to investigate the rheological properties of different confectionary creams, by scanning the field of shear rates at constant temperature and frequency, angular frequency scanning at small deformations and quantification of rheological changes during application of deformation voltages. The creams tested were made in the laboratory using specific concentrates as fine powders, marketed by the company “Dr. Oetker” compared with similar creams based on traditional recipes and techniques. Following the researches conducted we could conclude that both traditional creams and the instant ones are semi fluid food products with pseudoplastic and thixotropic shear flow behavior, with structural viscosity. Instant and traditional creams behaved as physical gels with links susceptible to destruction, when subjected to deformation forces.