A short oxazolidine-2-one containing peptide forms supramolecular hydrogels under controlled conditions

Low-molecular-weight hydrogels are made of a small percentage of small organic molecules dispersed in an aqueous medium, which may aggregate in several manners using different methods. However, often the organic gelator in water has poor solubility, so the addition of a solubilising agent is required. In the case of acidic gelators, this mainly consists of the addition of a strong base, that is sodium hydroxide, that deprotonates the acidic moiety, so the gelator molecules become more soluble and tend to assemble into micelles, forming a dispersion. Some gelators, however, are sensitive to the harsh pH and get hydrolysed. This is the case of some molecules presenting carbamates in their features, like Fmoc-protected or oxazolidinone-containing peptides. In this paper, we present a valid alternative to sodium hydroxide, by dissolving a tripeptide containing an oxazolidinone moiety in a phosphate buffer (PB) medium at pH 7.4. The results obtained with the NaOH dissolution are compared with the ones with PB, as both methods present advantages and drawbacks. The use of NaOH produces transparent but weak hydrogels, as it exposes the gelator to harsh conditions that end up in its partial hydrolysis, which is more pronounced at high concentrations (≥10 mM). Using PB to dissolve the gelator, this problem is completely avoided as no hydrolysis product has been detected in the hydrogels, which are very stiff although more opaque. By tuning the preparation conditions, we can obtain a wide variety of hydrogels, with the properties required by the final application

Low-Molecular-Weight Gels as Smart Materials for the Enhancement of Antioxidants Activity

Antioxidants are important substances used in the cosmetic and pharmaceutical fields that are able to block free radicals. These compounds can be incorporated into formulations for many reasons, such as release over time or preservation of the formulation activity and applicability. In the present study, a low-molecular-weight gel made with Boc-L-DOPA(Bn)2 -OH was studied as suitable material to host antioxidants and improve their activity. The solvent change (DMSO/H2O) in combination with temperature was the technological procedure for the preparation of the gel. Two different antioxidants were tested: (1) α-tocopherol and (2) postbiotics. The antioxidant activity of α-tocopherol and of the postbiotics in the gel, measured by the (2,2-diphenyl-1-picryl-hydrazyl radical (DPPH) assay, showed higher values than those in the pure solvent. The antioxidant activity of the gel with 0.8 w/v% of gelator and α-tocopherol in the concentration range of 5–100 µM was 2.7–1.1 times higher on average than in the pure solvent. In the case of both postbiotics, the biggest difference was observed at 30% of postbiotics in the gel with 0.5% of a gelator, when the antioxidant activity was 4.4 to 4.7 times higher than that in the pure solvent

Prospective Life Cycle Assessment of a Model Magnesium Battery

Energy-storage systems are considered as a key technology for energy and mobility transition. Because traditional batteries have many drawbacks, there are tremendous efforts to develop so-called postlithium systems. The magnesium-sulfur (MgS) battery emerges as one alternative. Previous studies of Mg-S batteries have addressed the environmental footprint of its production. However, the potential impacts of the use-phase are not considered yet, due to its premature stage of development. Herein, a first prospective look at the potential environmental performance of a theoretical Mg-S battery for different use-phase applications is given to fill this gap. By means of the life cycle assessment (LCA) methodology, an analysis of different scenarios and a comparison with other well-established technologies are conducted. The results suggest that the environmental footprint of the Mg-S is comparable with that of the commercially available counterparts and potentially outperforms them in several impact categories. However, this can only be achieved if a series of technical challenges are first overcome

Both JNK and apoptosis pathways regulate growth and terminalia rotation during Drosophila genital disc development

Apoptosis is necessary for the regulation of growth during development, but the precise details of this regulation have not been completely characterized. In this study, we used the Drosophila genital disc as a model to analyze the contribution of apoptosis to growth regulation. We studied the expression or activity of several elements of the apoptotic death pathway such as Drosophila inhibitor of apoptosis1, caspases, the apoptotic genes reaper (rpr) and head involution defective, as well as elements of the Jun-NH2-terminal kinase (JNK) pathway. We found that the JNK pathway is active in a dynamic, asymmetric and genitalia-specific manner. Apoptosis, as measured in terms of the expression of a variety of apoptotic molecules, occurs in a JNK-dependent and -independent manner and was detected among engrailed (en) expressing cells. JNK regulation of apoptotic genes is necessary to control growth in both sexes and rotation in males; this regulatory role is necessary to execute en(+) cell death and to activate expression of rpr in these cells. rpr is up-regulated at antero-posterior borders, and this expression appears to be of particular importance in the control of growth, since the balance between cell proliferation and death in those regions appears to depend on the equilibrium between pro- and anti-apoptotic factors at a cellular level.Fil: Benitez, Sergio Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Fisiología. Laboratorio de Genética del Desarrollo; ArgentinaFil: Sosa, Claudia Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Fisiología. Laboratorio de Genética del Desarrollo; ArgentinaFil: Tomasini, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Fisiología. Laboratorio de Genética del Desarrollo; ArgentinaFil: Macías, Ana. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Fisiología. Laboratorio de Genética del Desarrollo; Argentin

Accounting of vehicles

Актуальность исследования определяется возросшей необходимостью наличия транспортного средства для каждой компании. Автомобиль - это всегда большие затраты, учет которых «ложится на плечи» бухгалтерии. В организации должны быть разработаны внутренние положения, инструкции, иные организационно-распорядительные документы, необходимые для организации учета основных средств, включая автотранспортные средства, и контроля за их использованием. Методы ведения бухгалтерского учета в организации - это один из сложных вопросов управления компанией. Цель работы: установление статей расходов на транспортное средство в бухгалтерском учете. Методы исследования: методы эмпирического исследования (наблюдение, сравнение) и методы теоретического исследования (абстрагирование, анализ и синтез, индукция и дедукция, мысленное моделирование, восхождение от абстрактного к конкретному). Результаты. Рассмотрены основные затраты на содержание автомобильного транспорта, проанализированы имеющиеся теоретические материалы по выбранной тематике, государственные законодательные акты. Принимая во внимание изменения в законодательстве 2017 года, выбрана методика внесения затрат на автомобильный транспорт в бухгалтерский учет.The relevance of the study is determined by the increased need for each company in a vehicle. A car is always a big expense, which should be recorded by accountant. A company should develop internal regulations, instructions, other organizational and administrative documents required for accounting fixed assets, including vehicles, and control over their use. Method of accounting in the organization is one of the complex issues of company management. The aim of the study is to determine the items of expenses for a vehicle in accounting. Methods of research: methods of empirical research (observation, comparison) and methods of theoretical research (abstraction, analysis and synthesis, induction and deduction, mental modeling, climbing from the abstract to the concrete). Results. The paper considers the main expenses for maintaining motor transport. The authors have analyzed the theoretical materials on the chosen subjects, state legislative acts and selected the method of entering the costs for road transport into accounting taking into account the changes in the legislation of 2017

Biocompatible and Light-Penetrating Hydrogels for Water Decontamination

Solar light-activated photocatalyst nanoparticles (NPs) are promising environment-friendly low cost tools for water decontamination, but their dispersion in the environment must be minimized. Here, we propose the incorporation of TiO2-NPs (also in combination with graphene platelets) into highly biocompatible hydrogels as a promising approach for the production of photoactive materials for water treatment. We also propose a convenient fluorescence-based method to investigate the hydrogel photocatalytic activity in real time with a conventional fluorimeter. Kinetics analysis of the degradation profile of a target fluorescent model pollutant demonstrates that fast degradation occurs in the matrix bulk. Fluorescence anisotropy proved that small pollutant molecules diffuse freely in the hydrogel. Rheological and scanning electron microscopy characterization showed that the TiO2-NP incorporation does not significantly alter the hydrogel mechanical and morphological properties

Environmental assessment of a new generation battery: The magnesium-sulfur system

As environmental concerns mostly drive the electrification of our economy and the corresponding increase in demand for battery storage systems, information about the potential environmental impacts of the different battery systems is required. However, this kind of information is scarce for emerging post-lithium systems such as the magnesium-sulfur (MgS) battery. Therefore, we use life cycle assessment following a cradle-to-gate perspective to quantify the cumulative energy demand and potential environmental impacts per Wh of the storage capacity of a hypothetical MgS battery (46 Wh/kg). Furthermore, we also estimate global warming potential (0.33 kg CO2 eq/Wh) , fossil depletion potential (0.09 kg oil eq / Wh), ozone depletion potential (2.5E-08 kg CFC-11/Wh) and metal depletion potential (0.044 kg Fe eq/Wh), associated with the MgS battery production. The battery is modelled based on an existing prototype MgS pouch cell and hypothetically optimised according to the current state of the art in lithium-ion batteries (LIB), exploring future improvement potentials. It turns out that the initial (non-optimised) prototype cell cannot compete with current LIB in terms of energy density or environmental performance, mainly due to the high share of non-active components, decreasing its performance substantially. Therefore, if the assumed evolutions of the MgS cell composition are achieved to overcome current design hurdles and reach a comparable lifespan, efficiency, cost and safety levels to that of existing LIB; then the MgS battery has significant potential to outperform both existing LIB, and lithium-sulfur batteries

Delivery of Active Peptides by Self-Healing, Biocompatible and Supramolecular Hydrogels

Supramolecular and biocompatible hydrogels with a tunable pH ranging from 5.5 to 7.6 lead to a wide variety of formulations useful for many different topical applications compatible with the skin pH. An in vitro viability/cytotoxicity test of the gel components demonstrated that they are non-toxic, as the cells continue to proliferate after 48 h. An analysis of the mechanical properties demonstrates that the hydrogels have moderate strength and an excellent linear viscoelastic range with the absence of a proper breaking point, confirmed with thixotropy experiments. Two cosmetic active peptides (Trifluoroacetyl tripeptide-2 and Palmitoyl tripeptide-5) were successfully added to the hydrogels and their transdermal permeation was analysed with Franz diffusion cells. The liquid chromatography-mass spectrometry (HPLC-MS) analyses of the withdrawn samples from the receiving solutions showed that Trifluoroacetyl tripeptide-2 permeated in a considerable amount while almost no transdermal permeation of Palmitoyl tripeptide-5 was observed

Effect of hypoxia-inducing ions on chondrogenic differentiation in adipose derived mesenchymal stem cells within alginate matrix

Cartilage is a highly organized tissue with complex biomechanical properties, but since it has a poor intrinsic capacity of self-healing, injuries at this site usually lead to several problems, often ending in disabling symptoms. Although, different approaches have been proposed, even now cartilage repair represents a great challenge for orthopaedic surgeons (1, 2). One of the promising approach is given from tissue engineering, employing the combination of biomaterials and cell therapy to develop new therapeutic strategies. In this paper, we describe the behaviour of human adipose derived mesenchymal stem cells encapsulated into Ca/Co alginate beads as potential chondrogenic inducing biomaterial tacking advance on the synergy between alginate matrix and Co+2 ions without employing other expensive growth factors such as TGFbs or BMPs. The expression of chondrogenic markers such as sox9, collagen type II, and versican was investigated by Real Time PCR and Western blotting analysis. The expression of hif1mRNA was investigated to check the capability of Co+2 ions to induce a chemical hypoxia. Real Time PCR and WB data reveal a different cells behaviour on chondrogenic marker expression. In conclusion, the synergic effect of alginate and Co+2 ions can represent a valid strategy for chondrogenic differentiation of stem cells