scholarly journals Preface

2009 ◽  
Vol 81 (7) ◽  
pp. iv
Author(s):  
João Costa Pessoa

Knowledge of the chemistry and biochemistry of vanadium has increased enormously since the early 1980s, particularly that of vanadium(III), (IV), and (V). This led to remarkable developments in the understanding and recognition of the properties of vanadium compounds. A consequence of these new insights has been numerous applications of vanadium complexes ranging from therapeutics to catalysis and from new materials to green chemistry. Many of the more recent advances were presented at the 6th International Vanadium Symposium held 17‚Äì19 July 2008 in Lisbon, Portugal.The conference included 56 oral communications and 52 poster presentations. The following 12 papers are a selection from the oral communications presented. This conference attracted over 100 participants from 27 countries and 4 continents. The inorganic chemistry of vanadium, application of vanadium chemistry in catalysis and organic synthesis, and biological aspects of vanadium chemistry were discussed in invited lectures as well as in poster communications.The Vanadium Award, a prize first introduced at the 4th International Vanadium Symposium held in 2004 in Szeged, Hungary to recognize an outstanding contributor to the advancement of vanadium science, was awarded in 2008 to Prof. Toshikazu Hirao of the Osaka University, Japan, and his contribution is the first paper presented herein.The additional contributions that embody this issue are mostly papers covering aspects related to catalytic applications of vanadium compounds, including their use as functional models of vanadiumdependent haloperoxidases. Electron transfer in oxo and non-oxo vanadium complexes, the use of NMR to characterize the complexes, and synthesis of new polyoxovanadates are the subjects of other papers included.We look forward to the 7th International Vanadium Symposium to be held in Japan in 2010, where additional studies on the role of vanadium in life, the vanadium nutritional essentiality, vanadium toxicity, and vanadium therapy, as well as new contributions to the use of vanadium compounds in catalysis, including "green chemical" industrial applications, will certainly be presented.João Costa PessoaConference Chair

2005 ◽  
Vol 77 (9) ◽  
pp. iv ◽  
Author(s):  
Kenneth Kustin ◽  
Tamas Kiss

The following 10 papers are selections from the 4th International Symposium on Chemistry and Biological Chemistry of Vanadium held 3-5 September 2004 in Szeged, Hungary. This conference attracted over 110 participants from 25 countries and 4 continents. Plenary and invited lectures as well as posters discussed the inorganic chemistry of vanadium, vanadium chemistry in catalysis and organic synthesis, and biological aspects of vanadium chemistry. A new feature was introduced: the presentation of the Vanadis Award.The purpose of the Vanadis Award is to recognize an outstanding contributor to the advancement of vanadium science. The award will be presented at each International Vanadium Symposium prior to a lecture to be given by the recipient. It is awarded on the basis of contributions to a discipline or combination of disciplines of vanadium science, and is presented to an investigator who has produced innovative research with impact on the direction of the field. The nominee is selected on the basis of the following criteria: (1) Innovative research: A history of development or expansion of techniques and procedures and discovery of new chemical, biochemical, biological, technological, or pharmaceutical systems; (2) Development of new applications in one or more of the following areas: chemistry, biochemistry, biology, pharmaceutical science, materials science, and nanotechnology; (3) Wide-ranging influence of the nominee's work on the research of others in one or more disciplines; (4) History of highquality and -impact publications; and (5) Service of the nominee to progress, application, and exploration of vanadium in science. The recipient of the first Vanadis Award is Prof. Debbie C. Crans of Colorado State University, whose award address is the first contribution to be presented herein.The additional contributions begin with papers covering various aspects of the inorganic chemistry of vanadium. These papers are followed by descriptions of recent results in the use of vanadium compounds to further organic synthesis, and on the catalytic behavior of interesting vanadium complexes. The final selection includes papers dealing with the role of vanadium in haloperoxidases, or as insulin-mimetic compounds, which may be orally administered replacements of insulin injections.A tremendous increase in studies of aqueous vanadium chemistry over the past decade has been driven by the need to comprehend the diverse biological effects of vanadium. Examples of the rich array of data and concepts needed to explain the biological role of vanadium are given by models of the vanadium-containing haloperoxidase enzyme activity. However, this selection of papers from the 4th International Vanadium Symposium indicates that basic inorganic studies and a wide range of applications of vanadium chemistry to fundamental chemical problems of synthesis, reactivity, and catalysis are not lacking. Indeed, we look forward to the 5th International Vanadium Symposium to be held in San Francisco, CA USA in the fall of 2006, where additional fundamental studies linked to the need to better understand vanadium nutritional essentiality, vanadium toxicity, vanadium therapy, and vanadium catalysis, including "green chemical" industrial applications will be presented.Kenneth Kustin and Tamas KissConference Editors


2019 ◽  
Vol 4 (1) ◽  
pp. 63-72 ◽  
Author(s):  
Mirosław Krośniak ◽  
Janusz Szklarzewicz ◽  
Ryszard Gryboś ◽  
Barbara Tatar ◽  
Metin Yildirim ◽  
...  

Vanadium is an element that has an effect on improving glucose levels in animals with diabetes. However, its operation is strongly dependent on the chemical structure of compounds of this element. The influence of newly synthesized vanadium compounds on biochemical processes is also unknown. The paper presents the influence of eight new vanadium compounds on organ weights of animals (mice NZO) in whom diabetes was induced by a high-fat diet during 8 weeks. Tested vanadium complexes were administered by 5 weeks. After this time organs were collected and weighed. Tested complexes had a remarkable different effect on organ weights, despite having similar composition ([VO(L)(phen)] and the same co-ligand (1,10-phenanthroline) . This indicate on separate metabolic pathways of these compounds in the body of tested animals and role of the tridentate L Schiff base ligands. The compounds C2, C3 and C5 shoved biggest influence on organs weight and these results suggest influence on the metabolic pathways and therefore are interesting for further investigations.


2014 ◽  
Vol 60 (4) ◽  
pp. 416-429 ◽  
Author(s):  
E.V. Fedorova ◽  
A.V. Buryakina ◽  
N.M. Vorobieva ◽  
N.I. Baranova

The review considers the biological role of vanadium, its participation in various processes in humans and other mammals, and the anti-diabetic effect of its compounds. Vanadium salts have persistent hypoglycemic and antihyperlipidemic effects and reduce the probability of secondary complications in animals with experimental diabetes. The review contains a detailed description of all major synthesized vanadium complexes having antidiabetic activity. Currently, vanadium complexes with organic ligands are more effective and safer than the inorganic salts. Despite the proven efficacy of these compounds as the anti-diabetic agents in animal models, only one organic complex of vanadium is currently under the second phase of clinical trials. All of the considered data suggest that vanadium compound are a new promising class of drugs in modern pharmacotherapy of diabetes.


2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Peter J. Wellmann

AbstractThroughout human history, most further developments or new achievements were accompanied by new materials or new processes that enabled the technologic progress. With concrete devices and applications in mind, synthesis and subsequent treatment of materials naturally went along with the progress. The aim of the underlying article is to spot the role of optimization, of discovery, of trial-and-error approaches, of fundamentals and curiosity driven design and development. In a consecutive examination, five missions addressing the challenges facing our world (identified by the European Council) will be cross linked with seven topical areas from materials science defined by the European Materials Research Society. The scope of this examination is to identify approaches and methods to further develop and innovate materials which form the basis of the anticipated solutions.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1729
Author(s):  
Patrizio Raffa

The study of interactions between polyelectrolytes (PE) and surfactants is of great interest for both fundamental and applied research. These mixtures can represent, for example, models of self-assembly and molecular organization in biological systems, but they are also relevant in industrial applications. Amphiphilic block polyelectrolytes represent an interesting class of PE, but their interactions with surfactants have not been extensively explored so far, most studies being restricted to non-associating PE. In this work, interactions between an anionic amphiphilic triblock polyelectrolyte and different types of surfactants bearing respectively negative, positive and no charge, are investigated via surface tension and solution rheology measurements for the first time. It is evidenced that the surfactants have different effects on viscosity and surface tension, depending on their charge type. Micellization of the surfactant is affected by the presence of the polymer in all cases; shear viscosity of polymer solutions decreases in presence of the same charge or nonionic surfactants, while the opposite charge surfactant causes precipitation. This study highlights the importance of the charge type, and the role of the associating hydrophobic block in the PE structure, on the solution behavior of the mixtures. Moreover, a possible interaction model is proposed, based on the obtained data.


Cells ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 113 ◽  
Author(s):  
Stephanie Maia Acuña ◽  
Lucile Maria Floeter-Winter ◽  
Sandra Marcia Muxel

An inflammatory response is essential for combating invading pathogens. Several effector components, as well as immune cell populations, are involved in mounting an immune response, thereby destroying pathogenic organisms such as bacteria, fungi, viruses, and parasites. In the past decade, microRNAs (miRNAs), a group of noncoding small RNAs, have emerged as functionally significant regulatory molecules with the significant capability of fine-tuning biological processes. The important role of miRNAs in inflammation and immune responses is highlighted by studies in which the regulation of miRNAs in the host was shown to be related to infectious diseases and associated with the eradication or susceptibility of the infection. Here, we review the biological aspects of microRNAs, focusing on their roles as regulators of gene expression during pathogen–host interactions and their implications in the immune response against Leishmania, Trypanosoma, Toxoplasma, and Plasmodium infectious diseases.


Author(s):  
Fulvio Reggiori ◽  
Hans-Joachim Gabius ◽  
Massimo Aureli ◽  
Winfried Römer ◽  
Sandro Sonnino ◽  
...  

AbstractGlycans have been shown to function as versatile molecular signals in cells. This prompted us to look at their roles in endocytosis, endolysosomal system and autophagy. We start by introducing the cell biological aspects of these pathways, the concept of the sugar code, and provide an overview on the role of glycans in the targeting of lysosomal proteins and in lysosomal functions. Moreover, we review evidence on the regulation of endocytosis and autophagy by glycans. Finally, we discuss the emerging concept that cytosolic exposure of luminal glycans, and their detection by endogenous lectins, provides a mechanism for the surveillance of the integrity of the endolysosomal compartments, and serves their eventual repair or disposal.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
J. Norberto Pires ◽  
Amin S. Azar ◽  
Filipe Nogueira ◽  
Carlos Ye Zhu ◽  
Ricardo Branco ◽  
...  

Purpose Additive manufacturing (AM) is a rapidly evolving manufacturing process, which refers to a set of technologies that add materials layer-by-layer to create functional components. AM technologies have received an enormous attention from both academia and industry, and they are being successfully used in various applications, such as rapid prototyping, tooling, direct manufacturing and repair, among others. AM does not necessarily imply building parts, as it also refers to innovation in materials, system and part designs, novel combination of properties and interplay between systems and materials. The most exciting features of AM are related to the development of radically new systems and materials that can be used in advanced products with the aim of reducing costs, manufacturing difficulties, weight, waste and energy consumption. It is essential to develop an advanced production system that assists the user through the process, from the computer-aided design model to functional components. The challenges faced in the research and development and operational phase of producing those parts include requiring the capacity to simulate and observe the building process and, more importantly, being able to introduce the production changes in a real-time fashion. This paper aims to review the role of robotics in various AM technologies to underline its importance, followed by an introduction of a novel and intelligent system for directed energy deposition (DED) technology. Design/methodology/approach AM presents intrinsic advantages when compared to the conventional processes. Nevertheless, its industrial integration remains as a challenge due to equipment and process complexities. DED technologies are among the most sophisticated concepts that have the potential of transforming the current material processing practices. Findings The objective of this paper is identifying the fundamental features of an intelligent DED platform, capable of handling the science and operational aspects of the advanced AM applications. Consequently, we introduce and discuss a novel robotic AM system, designed for processing metals and alloys such as aluminium alloys, high-strength steels, stainless steels, titanium alloys, magnesium alloys, nickel-based superalloys and other metallic alloys for various applications. A few demonstrators are presented and briefly discussed, to present the usefulness of the introduced system and underlying concept. The main design objective of the presented intelligent robotic AM system is to implement a design-and-produce strategy. This means that the system should allow the user to focus on the knowledge-based tasks, e.g. the tasks of designing the part, material selection, simulating the deposition process and anticipating the metallurgical properties of the final part, as the rest would be handled automatically. Research limitations/implications This paper reviews a few AM technologies, where robotics is a central part of the process, such as vat photopolymerization, material jetting, binder jetting, material extrusion, powder bed fusion, DED and sheet lamination. This paper aims to influence the development of robot-based AM systems for industrial applications such as part production, automotive, medical, aerospace and defence sectors. Originality/value The presented intelligent system is an original development that is designed and built by the co-authors J. Norberto Pires, Amin S. Azar and Trayana Tankova.


2020 ◽  
Vol 11 (2) ◽  
pp. 375-386
Author(s):  
Hamed Ahmad Almahadin ◽  
Yazan Salameh Oroud

This study aims to investigate the moderating role of profitability in the relationship between capital structure and firm value in Jordan, as an example of an emerging economy. For this purpose, two functional models were formulated to capture the direct relationship as well as the interaction impact of capital structure on firm value. The robust empirical findings of panel data analysis provide strong evidence of an adverse relationship between capital structure and firm value. The findings confirm that the impact of capital structure appears to be complicated in nature and difficult to examine without controlling for the interaction of profitability as one of the major determinants. Therefore, studying the interaction effect provides ample evidence and enhances the understanding of the link between firm value and capital structure. The empirical results of the study may provide important insights and policy implications to decision-makers.


2019 ◽  
Vol 179 (4) ◽  
pp. 269-273
Author(s):  
Jarosław KAŁUŻNY ◽  
Natalia IDASZEWSKA ◽  
Tomasz RUNKA ◽  
Adam PIASECKI ◽  
Marek NOWICKI ◽  
...  

In the recent years industrial applications of carbon allotropes such as carbon nanotubes (CNTs) and graphene have been tested extensively, thus justifying research on the environmental impact these materials have. In the current paper we compare EDS spectroscopy results of a cabin filter used in a car to a filter used in an air purifier inside a residential space. The contaminants adsorbed on the carbon nanoparticles trapped in both types of filters allows for determining of their source of origin demonstrating clearly the dominant role of non-road emissions in Poland. Finally we present the experimental study on the growth of plants on substrates intentionally enriched with CNTs.


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