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  • Author: Diana Muntean x
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Abstract

The research aims to test polymer materials as the plastic materials: UHMWPE and POM, to observe there characteristics, to determing how they can be used and what we can obtain from them. We wanted to see the strong and the weak values that characterize them, what kind of parts we can produce from them and in what case we can use it. By applying this tests is necessary in order to see real datas that can help you compare them, and lead you to conclusions. Using these methods of testing materials leads to the establishment of real properties of the material and to the establishment of new configurations necessary to be made to the manufactured parts.

Abstract

Innovation is not a simple concept but is the main source of success. It is more important to have the right people and mindsets in place than to have a perfectly crafted plan in order to make the most out of an idea or business. The aim of this paper is to emphasize the importance of intangible assets when it comes to machine vision inspection of thermoplastic materials pointing out some aspects related to knowledge based assets and their need for a success idea to be developed in a successful product.

Abstract

Phisical activity, regularly performed, give us a lot of health benefit, especially in preventing cardiovascular disease, diabetes mellitus (DM) and obesity. Physical exercise, defined as a controlled, progressive, supervised, requires muscular activity, involving energy consumption through metabolic and thermoregulatory processes. It can be classified as aerobic and anaerobic, according to the metabolic processes that take place. The metabolic equivalent (MET) represents the body’s energy consumption during rest and it is used for quantifying fhisical activity (for example, a MET value of 3 would require 3 times the energy that is consumed at rest). Muscle contraction has two different phases: the isometric one (usually during the first part of the contraction) and the isotonic one. This article presents the interrelation of phisical activity with with the complexity of metabolic patwais, bringing the arguments for the necessity of performing regular and controlled phisical activity.

Abstract

The increasing resistance against classical antibiotic treatment forces the researchers to develop novel non-toxic antimicrobial agents. The aim of this study was to determine the antimicrobial properties of seven different porphyrins having distinctive hydrophobicity/hydrophilicity: P1 meso-tetra(4-methoxy-phenyl)porphyrin, P2 Zn(II)-meso-5,10,15,20-tetrapyridylporphyrin, P3 meso-tetra(p-tolyl)porphyrin, P4 5,10,15,20-tetraphenylporphyrin; P5 (5,10,15,20-tetraphenylporphinato) dichlorophosphorus(V) chloride, P6 5,10,15,20-tetrakis-(N-methyl-4-pyridyl) porphyrin-Zn(II) tetrachloride, P7 Zn(II)-5,10,15,20-meso-tetrakis-(4-aminophenyl)porphyrin. The meso-porphyrin derivatives were screened for their antimicrobial activity against six reference strains: Streptococcus pyogenes ATCC 19615, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Klebsiella pneumoniae ATCC 700603, Pseudomonas aeruginosa ATCC27853 and Candida albicans ATCC 10231. The antimicrobial activity of these samples was evaluated by the agar disk diffusion method and dilution method, with the determination of the minimum inhibitory concentration (MIC), the minimum bactericidal concentration (MBC) and the minimum fungicidal concentration (MFC). The most significant result is provided by the water-soluble P5 manifesting an obvious antimicrobial activity against Streptococcus pyogenes. On the other hand, P6 is a moderately active derivative against Streptococcus pyogenes and Escherichia coli and P7 presents moderate activity against Streptococcus pyogenes and Staphylococcus aureus. All the tested porphyrin bases, presenting hydrophobic character, have no antimicrobial activity under the investigated conditions. The common characteristics of the porphyrins that act as promising antimicrobial agents in the non-irradiated methods are: the cationic nature, the increased hydrophilicity and the presence of both amino functional groups grafted on the porphyrin ring and the coordination with Zn or phosphorus in the inner core.

Abstract

Background: Snake venom is a complex mixture of biologically active substances. Some peptides and proteins from snake have already demonstrated their therapeutically potential. The venom of Naja haje, an Elapidae member, has been analyzed from this point of view. Understanding the fully biochemical role of its enzymes has determined the scientists to find new separation and identification methods.

Objective: Our goal was to develop an optimal HPLC analytical method for separation and identification of Naja haje snake venom components, known for its neurotoxic activity. In addition, we wanted to find out if crude snake venom could inhibit the development of both Gram-positive and Gram-negative bacterial cultures. Materials and Method: Analysis of venom was performed on a HPLC system using a C16 column with UV detection at 210 nm. The analysis was done using two mobile phases, containing different concentrations of acetonitrile and trifluoroacetic acid aqueous solution at different pH values. An elution gradient was set at a flow of 0.60 mL/min. Bactericidal activity was quantified by measuring inhibition diameter around an aseptically disk filled with crude venom using Staphylococcus aureus and Escherichia coli. Results: An optimal HPLC analytical method has been developed by changing different parameters such as the pH value of mobile phase A or the elution gradient. The best resolution were obtained at a pH value of 7.4, in gradient varying from 5% to 45% in mobile phase B. Microbiological studies of the venom showed that Gram-positive bacteria growth was inhibited by crude venom, while on Gram-negative bacteria growth no effect was observed. Inhibition zone is dose-dependent and fresh crude venom is with 30% more potent than venom freeze and kept at -55°C. Conclusions: A comprehensive catalog of venom composition may serve as a starting point for studying structurefunction correlations of individual toxins for the development of new research tools and drugs of potential clinical use.

Abstract

As the latest data from the International Diabetes Federation (IDF) have shown, diabetes mellitus (DM) prevalence and incidence are continually increasing. Our purposes were to identify the socio-demographical characteristics of the subjects diagnosed with DM prior to this study, to establish the percent they represent of the studied group, to evaluate the metabolic control of the subjects enrolled in the study, as well as to ascertain whether the blood glucose level or the glycated haemoglobin (HbA1c) measurement leads to the detection of a higher percentage of DM newly diagnosed cases. The study conducted in 3 Romanian cities enrolled 4133 subjects (1340 from Craiova, 1224 from Oradea and 1569 from Sibiu). 1413 subjects (34%) reported having been diagnosed with DM prior to our study. Most of the subjects previously diagnosed with DM, 65%, take oral antidiabetic agents (OAA), 13% take insulin and 4% take both OAA and insulin. 20% of the subjects who did not report DM had a blood glucose level ≥126mg/dL and 17% of them had an HbA1c ≥6.5%, leading to a high number of newly diagnosed DM cases, therefore emphasising the importance of the simultaneous determination of these two parameters. The results of this study confirm the increasing prevalence of DM and the necessity of future studies in order to asses DM accurate prevalence in Romania.