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Ultrastructural Changes of Organelles in Root Cap Cells of Tobacco Under Salinity

Abstract

We investigated how an abiotic factor, i.e. salinity, affects specific intracellular organelles of cells of the root cap. We focused on: 1) amyloplasts, which are specific plastids of the cap that perform important metabolic and sensory functions; and 2) mitochondria, which protect cells from ROS damage by changing their ultrastructure. In our work we studied the ultrastructural changes of these organelles in different areas of the root cap under NaCl and Na2SO4 impact. We showed that the amyloplasts (statoliths) and mitochondria of the columella and the peripheral zone of the cap change their structural organisation in the presence of NaCl. Under action of Na2SO4, in plastids of columella the number of starch grains decreases dramatically, the cells of the peripheral part of the cap do not contain the amyloplasts, and the proplastids that do not store or store a little starch grains, which is attributed to leucoplasts with typical lamellae characteristic for root cortex cells. Thus, Na2SO4 influence has the most significant effect on the plastids of the root cap, and plastids of the cells of the peripheral zone of the cap are subjected to the most significant changes under salinity stress.

Open access
Argumentation – Evidentiary Procedure in Criminal Proceedings

Abstract

The continuous increase in criminal activities in all countries, namely the offences which undermine the interests of contemporary societies, call for the need to fight them in a more successful manner. In this way, the country through its mechanisms detects the criminal offences, the criminal liability and imposes the meritorious sanction to the perpetrators of such criminal offences, in full compliance with the danger caused by them. However, the court and other parties in the proceedings (Prosecution, Lawyer, Victim’s Advocate) in any case before the sanction is imposed, are involved in a complicated evidentiary proceedings related to the grounded suspicion that such offence was a criminal offence, the special mitigating and aggravating circumstances, that the person involved was conscious, that he committed the offence intentionally or negligently, his mental state, etc. All these have to be supported by facts through conclusive pieces of evidence. In parallel with the overall development of science and technology, the evidentiary procedure has evolved and it provides a greater possibility to argue our facts. This paper shall make efforts to highlight some of the most important issues related to the evidentiary procedure, such as: What is the evidence? What evidence should be provided in a certain criminal case? What is the importance of the evidence in a criminal matter? What should be the credibility and the evidentiary value of a piece of evidence? The research done in this paper shall apply the analytical method and the paper shall also include the conclusions that were reached as well as the recommendations.

Open access
Assessment of Cardiac Resynchronisation Therapy Efficacy Determining Factors for Patients with Moderate and Severe Heart Failure in the Population of Latvia in a 12 and 24 Month Study

Abstract

The aim of this study was to evaluate treatment of patients with moderate and severe heart failure (HF) who were resistant to pharmacotherapy in Latvia and to assess the cardiac resynchronisation therapy (CRT) by exploring the predisposing factors which provides CRT efficacy. We accomplished prospective analysis of left ventricle ejection fraction (LVEF) and other parameter changes 12 and 24 months after CRT device implantation, dividing the population into two groups: responders — to whom LVEF improvement was ≥10% and non-responders where ≥ 10% LVEF improvement was not achieved. The study included 50 chronic HF patients with preserved sinus rhythm, who underwent CRT device implantation in Latvia at the Pauls Stradiņš Clinical University Hospital from June 2009 to March 2012. In the group of patients where 12 and 24 months after CRT device implantation LVEF improvement ≥10% was achieved, there were statistically significantly more patients with left bundle branch block (LBBB) QRS morphology, wider QRS complex, nonischemic genesis of HF, and normal systolic blood pressure. Patients with LVEF improvement had more pronounced ventricular dyssynchrony measured by Echo before CRT device implantation and, accordingly, the CRT mode was programmed as left ventricle paced before right ventricle and close to 100% biventricular pacing was achieved and the patient was female.

Open access
The Benefits and Risks of Digital Diplomacy

Abstract

As a product of globalization and as a fruit of new public diplomacy, digital diplomacy is considered one of the major trends of the twenty-first century in diplomatic communication. Being under the influence of the extraordinary advances in ICT, the internet and social media, the way of realization and presentation of diplomacy has been radically changed and is increasingly removed from the traditional diplomatic elements. The importance of digital diplomacy is based on the usage of ICT, the internet and social media, which at the same time represent its base, for the strengthening of the diplomatic relations. Therefore, knowledge about the role and importance of digital diplomacy is indispensable. This paper will offer information on the definition, goals, evolution and effectiveness of the digital diplomacy. Meanwhile, the main focus of the research lies in the classification of its benefits and risks. For international actors is more than clear how useful is exploitation of digital diplomacy benefits for achieving their goals in the international arena. However, the process of digitization is unseparated from cyber risks, as well as the freedom of the internet and social media is abused for various purposes that state and non-state actors may have. Although coupled with benefits on the one hand and risks on the other hand, the risks of digital diplomacy are still covered by benefits, making digital diplomacy a key element for the realization of diplomatic activities. Based on all the information over the features of the topic, the primary goal of the paper is to provide sufficient arguments for verifying the abovementioned hypothesis, which is also the general hypothesis of the paper.

Open access
A Critical Analysis of Interpersonal Communication in Modern Times of the Concept “ Looking Glass Self (1902) ” By Charles Horton Cooley

Abstract

Influence of other’s assessments on individuals in society and their reaction is an amusing topic, given Cooley’s Looking Glass Self concept concerning this, simultaneously being the subject of this critical analysis. The fact manifesting an opinion that an individual’s true self changes due to other perceptions is often subjected to various critical considerations, creating the impression that in reality the concept is infeasible. The purpose is determining the “hole” in the third component, proving that the true self is occasionally susceptible to constant change, depending on other’s perceptions and the individual himself. Regarding the methodology, several methods were used to prove the critical attitude towards this topic. Applications of comparative analysis, descriptive and historical methods are present. Our result is concluding the individual develops a certain attitude influenced by different experiences, being crucial to whether he will be ready to change his true self or not.

Open access
Determination of Humectants in Tobacco Filler by High Performance Chromatography/Single Quadrupole Mass Spectrometry

Summary

Glycerol, and 1,2-propylene glycol are the humectants most commonly used by the tobacco industry. They are found in a variety of tobacco products and are often present at high levels (~2–5 % w/w). While humectants are generally considered safe, they may serve as precursors in the formation of harmful carbonyl compounds. A selective, precise, and sensitive method for the quantification of several humectants in cigarette filler was developed. The method’s sample clean-up is a two-step process consisting of a mechanical extraction, followed by solid phase extraction. Individual humectants are separated, identified, and measured using liquid chromatography coupled to a single quadrupole mass spectrometer as the detector (LC/MS). Detection limits were 0.105, 0.575, and 0.039 mg/cigarette for glycerol, 1,2-propylene glycol and triethylene glycol, respectively. The quantification range for these analytes was 0.4–75.0 mg/cigarette. Twenty-seven brands of domestic commercial cigarettes were evaluated to assess typical levels of humectants in the tobacco filler.

Open access
Determination of Hydrogen Cyanide in Cigarette Smoke by Continuous Flow Analysis Method Using Safer Chemistry

Summary

A new safe and sensitive method to determine hydrogen cyanide (HCN) in cigarette smoke using continuous flow analyser (CFA) has been developed and validated. The use of highly toxic potassium cyanide (KCN) as a standard necessitates the development of a safer method for the determination of HCN in cigarette smoke. In this described method KCN is replaced by less toxic potassium tetracyanozincate (Lethal Dose LD50 oral is 7.49 mg/kg for KCN and 2000 mg/kg for potassium tetracyanozincate). Furthermore, the new method uses isonicotinic acid-barbituric acid (coupling reagent) instead of pyridine-pyrazolone as a reagent for the determination of HCN, and hence eliminates the use of pyridine. In this method HCN is trapped on both the Cambridge Filter Pad, then extracted with aqueous sodium hydroxide solution, and in an impinger containing the same solution. The solution thus extracted is oxidised to cyanogen chloride by Chloramine-T and treated with coupling reagent, the resulting stable chromophore was measured colorimetrically at 600 nm. The regression equation was linear in the range of 1 to 25 μg/mL for cyanide with a correlation coefficient (R2) > 0.9998. The limit of detection (LOD) was 0.76 μg/cig and the overall relative standard deviation (RSD) of the method was less than 10%. Excellent recoveries of cyanide were obtained in the range from 92% to 112% and the HCN yields from the Kentucky Reference Cigarette 3R4F obtained from the newly developed method are in good agreement with those from the conventional KCN method. The proposed method is robust, reliable, selective and safer than any of the existing methods for determination of hydrogen cyanide in mainstream as well as in sidestream cigarette smoke.

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Editorial Foreward
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Editors’ Note
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