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Open access

Shintaro Ohashi

Summary

Safety and quality standards for electronic cigarettes (e-cigarettes) have been introduced regionally. In 2016, the U.S. Food and Drug Administration (FDA) issued a rule to regulate e-cigarettes, requiring to report harmful and potentially harmful constituents (HPHCs). In the United Kingdom, the British Standards Institution (BSI) specified the metals to be monitored for e-cigarettes. In this study, a method was developed and validated for the simultaneous determination of 13 metals (Be, Al, Cr, Fe, Co, Ni, Cu, As, Se, Ag, Cd, Sn and Pb) in e-cigarette aerosol. Furthermore, matrix effects of major constituents in the aerosol were investigated using glycerol or 1,2-propylene glycol solutions. E-cigarette aerosol was generated by a rotary smoking machine according to CORESTA Recommended Method N° 81 and collected by an electrostatic precipitator coupled to an impinger containing nitric acid. The collected aerosol was dissolved in nitric acid and an aliquot of this solution was analyzed by inductively coupled plasma mass spectrometry (ICP-MS) equipped with a collision/reaction cell.

The linearity of the calibration curve was observed in the range of 0.2 to 100 ng/mL for each analyte; the correlation coefficients were 0.998 or larger, the mean recovery of each standard level ranged from 92.6 to 104.5% and the relative standard deviation amounted to max. 9.5%. Accuracy, repeatability and specificity were validated by spiking three different amounts of analytes into e-cigarette aerosol; the mean recovery of each spiking level ranged from 88.7 to 110.3% with a relative standard deviation amounting to max. 9.2% for all analytes. Background contamination from aerosol generation and collection system existed for some analytes, especially for Al, Fe, Cu and Sn. The potential sources of contamination should be identified and controlled to reduce the impact of contamination on quantification. In addition, the actual values for samples should be reported with method blank statistics. Increase of the concentrations of glycerol and 1,2-propylene glycol in the prepared sample led to the overestimation of As and Se. The amount of polyols in the collected aerosol should be monitored and controlled for the accurate quantification of As and Se.

Open access

Ainārs Rudzītis, Kristaps Šablinskis, Baiba Luriņa, Irina Cgojeva-Sproģe, Aļona Grāve, Andis Dombrovskis, Pēteris Stradiņš and Andrejs Ērglis

Abstract

Percutaneous transcatheter device closure of secundum atrial septal defects (ASD) has now largely replaced surgical closure in most centres. The aim of this study was to compare results of transcatheter and surgical ASD closure in adults in Latvia during the years 2002–2014 and to analyse long-term outcomes of transcatheter closure. We analysed data from 334 patients with secundum ASD who underwent ASD closure in Pauls Stradiņš Clinical University Hospital. Patients were included into device or surgical closure groups. In the device group, three follow-ups were made 1, 6, and 12 months after the procedure. No follow-up data were available for surgical arm patients beyond their hospitalisation period. The mean age of patients was 45.3 ± 19.9 years for the device group and 40.0 ± 16.9 years for the surgical group (p = 0.023). The mean secundum ASD size in the device and surgical groups was 14.2 ± 5.6 mm and 28.7 ± 10.0 mm, respectively (p < 0.001). No differences were observed regarding procedure success rates: 99.2% in the device group and 100% in the surgical group (p = 0.451). Periprocedural complications generally were more common in the surgical closure group. The study results show a successful introduction of the percutaneous ASD closure method in Latvia with good early and late outcomes and without significant differences in procedure success rate compared to surgical closure.

Open access

Yerlan Turuspekov, Yuliya Genievskaya, Aida Baibulatova, Alibek Zatybekov, Yuri Kotuhov, Margarita Ishmuratova, Akzhunis Imanbayeva and Saule Abugalieva

Abstract

The genus Artemisia is one of the largest of the Asteraceae family. It is abundant and diverse, with complex taxonomic relations. In order to expand the knowledge about the classification of Kazakhstan species and compare it with classical studies, matK genes of nine local species including endemic were sequenced. The infrageneric rank of one of them (A. kotuchovii) had remained unknown. In this study, we analysed results of sequences using two methods — NJ and MP and compared them with a median-joining haplotype network. As a result, monophyletic origin of the genus and subgenus Dracunculus was confirmed. Closeness of A. kotuchovii to other species of Dracunculus suggests its belonging to this subgenus. Generally, matK was shown as a useful barcode marker for the identification and investigation of Artemisia genus.

Open access

Ibrahim Azizov, Elshan Shamilov, Asim Abdullayev, Zohra Muslimova, Gunel Mamedli and Gulnar Gasimova

Abstract

The influence of a medicinal plant extract, immobilised by ligands, on the activity of antioxidant enzymes and photosynthetic pigment concentration of wheat and maize was studied. The object of study was seed of drought-resistant firm durum wheat (Triticum durum Desf.) and maize (Zea mays L.). Seeds were subjected to general uniform γ-radiation from a 60Co source on a Rkhund installation at average dose power of MD = 0.306 Gy/sec. Before radiation seeds were treated in modified extract from medicinal plants. The treatment of seeds with 0.1 and 0.01% solution of modified extract from Hypericum, Dandelion, and Calendula caused significant reduction in processes initiated by radiation and in formation of free radicals. On the basis of the obtained results it was concluded that the used modified plant extract collection had a protective effect, reducing the amount of free radicals produced by γ-irradiation.

Open access

Inese Kolontaja-Zaube, Ināra Ančupāne, Andra Dērveniece, Aija Žileviča and Ilze Ķikuste

Abstract

Rosacea is a chronic inflammatory skin disorder affecting predominantly adult patients. The aim of the current investigation was to evaluate clinical response by using quality of life assessment before and after an IPL (intensive pulsed light) therapy course for patients sufferring from rosacea treated in the outpatient clinic “Health and Aesthetics” in Rīga during a one-year period (in 2016). All patients presented with typical clinical symptoms of rosacea on the face — acneiform papules, pustules, telangiectasia, centrofacial erythema, and complaints about flushing and burning. In the current study, 100 rosacea patients treated with IPL therapy were selected. Each patient filled in the quality of life questionnaire before and after two courses of IPL therapy. The interval between IPL therapy sessions was one month. The results reflected comprehensive benefit from IPL therapy for all rosacea patients. No serious side effects from IPL therapy were detected. Side effects like mild eythema after procedure (75%), mild oedema (10%), vesiculation (3%), and hyperpigmentation (8%) were completely resolved within four weeks after completion of treatment. In all patients, quality of life assessment showed a statistically significant increase after two courses of IPL therapy.

Open access

Jūlija Zepa, Inita Buliņa, Vladimirs Lavrentjevs, Ilze Vīnkalna, Liene Ņikitina-Zaķe, Daina Andersone and Aivars Lejnieks

Abstract

Obesity can be a factor that affects the course of chronic systemic inflammatory arthritis. The objective of this study was to characterise patients with ankylosing spondylitis (AS) according to an evaluation of their body mass index (BMI) and by exploring the link between the overweightness and obesity with routinely measured disease-specific variables, including disease activity (Bath Ankylosing Spondylitis Disease Activity Index BASDAI; Ankylosing Spondylitis Disease Activity Score, using CRP, ASDAScrp), spinal mobility (Bath Ankylosing Spondylitis Metrology Index, BASMI), functional capacity (BASFI), extraspinal manifestations like fatigue, uveitis, and peripheral arthritis present during the course of the disease. A total of 107 patients were included in the cross-sectional study fulfilling the modified New York criteria for AS. Patients were divided into three groups: with the evaluation of BMI ≤ 24.9, 25.0–29.9 (overweight) and ≥ 30.0 (obesity). The mean BMI was 25.13 (SD 4.07). 33% of patients were overweight and 15% were obese. The mean values of age, duration of AS, ASDAScrp, BASDAI, Bath Ankylosing Spondylitis Functional Index (BASFI), BASMI, pain in spine, and fatigue in the group with BMI ≤ 24.9 were lower than in the other groups (p < 0.05). There was no difference between groups in age of AS onset, uveitis and peripheral arthritis. AS patients who were overweight or obese had a higher level of the disease activity, pain, fatigue, functional disability and spinal mobility impairment with worse values in the case of obesity.

Open access

Artis Kalniņš, Ieva Strēle, Irēna Kurcalte, Aivars Lejnieks and Andrejs Ērglis

Abstract

Coronary artery chronic total occlusions (CTO) are common — approximately one-third of patients with significant coronary artery disease on angiography have at least 1 CTO. Invasive treatment of these lesions still remain a major challenge for interventional cardiology due to their complexity. Historically, success rates have improved to about 60–70% by using only the traditional antegrade approach. The results have dramatically improved during the last decade after more widespread application of new retrograde techniques. The aim of our study was to review and analyse single hospital experience in CTO invasive treatment and to evaluate the long-term results. A total of 519 patients undergoing percutaneous coronary interventions (PCI) for CTO at a single tertiary PCI centre (Rīga East University Hospital), were included in the study. The median age was 64 years (38–88), and 80% were male. The retrograde approach (RA) was used for 167 (32.2%) of the CTO PCI patients. The overall patient success rate was 81.3% and it increased from 73.9% in 2007 to 95.2% in 2015 (p < 0.001). Mean patient observation time was five years. Overall survival was found significantly better in patients group after successful CTO PCI procedures (Long-rank test, p = 0.013).

Open access

Roxana Săvescu, Ana Maria Stoe and Mihaela Rotaru

Abstract

Faculty of Engineering in Sibiu is facing an increasing demand from industrial companies to employ students not only by the time of graduation but even during university studies. The scope of the study was to provide an insight on working students’ profile and the problems they are confronting with. Forty working students from the third year of Faculty of Engineering Sibiu were interviewed with regard of the research topic. Results of the study reflect the fact that a majority of working students face difficulties in school, having low grades or failed exams. The exam session seems to be a hard period for working students, and many of them find difficulties in attending all lectures or finding time to learn. Having a job while studying impacts personal activities, as well. Stress symptoms like: loss of appetite or overeating, difficulties in focusing, difficulties in taking decisions or feelings of restless are mentioned by the majority of working students. The results of the study are useful for the management of the faculty to come up with some measures to increase working students’ lectures attendance. Student support programs for reducing the stress among the group of working students must be developed as well.

Open access

Lucian Lobonț, Radu Emanuil Petruse, Paul Mihai Obrodoviciu and Ioan Bondrea

Abstract

The development of the business - industry environment is unconceivable without the involvement of academia. On one hand, the universities can provide new perspectives and know-how which can be further translated into exquisite products and services for companies. On the other hand, the business environment can raise practical problems and challenges for academia, providing in the same time material support for finding solutions to these problems. This paper presents a successful partnership between business and academia materialized in the development of a robotized semiautomatic motorcycle transmission. Since the solutions existing on the market did not meet the specific requirements of our industrial partner, we were asked to design an innovative and cost effective clutch and gearbox mechanism. The paper presents all the stages passed from establishing specific objectives and tasks for each member of the project’s team, the specific steps followed in order to develop the clutch operation mechanism and the gear mechanism, the obstacles and failures encountered during the design process and the testing procedures, the optimizations implemented, up to the final solution. The advantages of such industry-academia projects are discussed and possible obstacles that can hinder this kind of collaboration are addressed.

Open access

Panagiota Digkoglou, Athanasios Dragoslis, Jason Papathanasiou and Vassilis Kostoglou

Abstract

The purpose of this work is to provide a ranking of eight European countries concerning their hotel industry. We have drawn data from TripAdvisor with various features, like the location of each hotel, the cleanness, the number of the rooms, the price of each hotel and other similar criteria. The analysis was conducted by using two multicriteria analysis methods, namely AHP and VIKOR. Specifically, the well known AHP method will help us to calculate the weights of the criteria and the ranking of the alternatives is provided by VIKOR. The obtained results provide vital information, more specifically which country has the more attractive hotel industry, compared with the other countries. Based on the obtained results in this research, we can see that there are two countries with the best hotel services and the ranking has a particular interest, as all eight countries are famous for their tourist services.