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Open access

Ahmed Mostafa and Heba Shaaban

Abstract

The study presents the application of multivariate curve resolution alternating least squares (MCR-ALS) with a correlation constraint for simultaneous resolution and quantification of ketoprofen, naproxen, paracetamol and caffeine as target analytes and triclosan as an interfering component in different water samples using UV-Vis spectrophotometric data. A multivariate regression model using the partial least squares regression (PLSR) algorithm was developed and calculated. The MCR-ALS results were compared with the PLSR obtained results. Both models were validated on external sample sets and were applied to the analysis of real water samples. Both models showed comparable and satisfactory results with the relative error of prediction of real water samples in the range of 1.70–9.75 % and 1.64–9.43 % for MCR-ALS and PLSR, resp. The obtained results show the potential of MCR-ALS with correlation constraint to be applied for the determination of different pharmaceuticals in complex environmental matrices.

Open access

A. Tripathi, L. Wangchu and A. K. Trivedi

Summary

This work investigated the relationship of host size, seasons, and water quality parameters with the prevalence and intensity of Cornudiscoides agarwali on Mystus bleekeri collected from the Dikrong River in Arunachal Pradesh, India from February 2016 to January 2017. A total of 2760 specimens of C. agarwali were recovered from 114 individuals of M. bleekeri. The levels of mean intensity, but not the prevalence, of infection of C. agarwali were positively correlated with fish host size, peaking in the largest size class (45.20 ± 5.69 parasites/fish). The prevalence values had a statistically significant seasonal trend, reaching highest (100 %) during the pre-monsoon season, followed by 91.8% during the post-monsoon period and 87.5 % during the monsoon season. The levels of mean intensity of infection were also dependent on the seasons, reaching significantly higher levels during the pre-monsoon season (42.75 ± 4.18 parasites/fish). All water quality parameters measured were within the safety value recommended for freshwater aquaculture. Cornudiscoides agarwali maintained its prevalence above 87.5 % throughout the annual cycle, which means it was able to reproduce year-round in a non-polluted river. This could be an indication of monogenoidean community and population dynamics thriving best under optimum water quality parameters. Also, this article draws the attention of parasitologists and ichthyologists to a taxonomic problem of the misidentification of Mystus spp., and therefore, possibly of their parasitic monogenoids.

Open access

S. Sadet Canakoglu, S. Simsek, I. Balkaya and S. Gunyakti Kilinc

Summary

Fasciolosis caused by Fasciola hepatica is a common parasitic disease of livestock especially sheep and cattle. In this study molecular characterization of β-tubulin isotype 3 gene in Fasciola hepatica isolates from cattle and sheep in Turkey was carried out. For this purpose a total of 80 adult Fasciola hepatica isolates were collected from 20 sheep and 20 cattle in Kayseri and Erzurum provinces. PCR-RFLP was performed on β-tubulin isotype 3 gene and MboII revealed two fragments of approximately 350 bp and 390 bp, whereas HphI enzyme yielded 210, 340 and 540 bp bands, HindII yielded 380 and 450 bp bands in all samples. A total of 80 isolates were tested by SSCP and all of them presented the same band profiles. Six samples (4 sheep and 2 cattle) were randomly selected and DNA sequence of a 935 bp coding fragment of β-tubulin isotype 3 was performed. Sheep samples were more polymorphic than the cattle. This β-tubulin isotype 3 gene polymorphism of F.hepatica isolates from sheep and cattle of two distinct geographical areas of Turkey have been investigated for the first time.

Open access

Jerzy J. Parysek

Abstract

This article presents the general characteristics of the Poznań school of socio-economic geography (and spatial management). Scientific school is usually understood as a community of scholars, representatives of a given scientific discipline, associated with a specific university (or universities) functioning in a given city, united by particular approaches to scientific problems and by accepted ideas, views, methods used etc., which has substantial achievements in a given scientific discipline. There is practically no scientific school without a master (or masters) who is an eminent scholar gathering a group of students and associates. The acknowledged output of this scholar – master, especially an innovative approach to solving research problems and also the influence of his/her scientific authority on students and associates, is usually an origin of a new scientific school. Professor Zbyszko Chojnicki, the founder of the Poznań school, was such a master. The article presents the creation of the School and its development, characterises the role of the Master, indicates the research approach and direction of the conducted studies he determined and discusses the scientific output of the Master and the three selected generations of students and, to a lesser extent, the auditing students. Emphasis is put on the achievements in the theory of geography and spatial management, methodology, paying particular attention to quantitative analysis methods and the innovative and original empirical research conducted as well as the significance of this output for Polish socio-economic geography and spatial management. What is also presented is the popularisation activity and the reflections on the future of the School. The article presents the author’s point of view.

Open access

Fahimed Koohdar, Masoud Sheidai and Seyed Mehdi Talebi

Abstract

Lallemantia royleana (Benth.) Benth. (Family Lamiaceae), is one of the most popular medicinal plants in Iran. It is an herbaceous pant that is commonly known as “Lady mantle”. The vernacular name of Lallemantia royleana’s seed is Balangu or Balangu Shirazi that is used as a source of medicine. Medicinal plants are very important from economic point of view in Iran and several large industries are focused on medicinal plants cultivation, extraction and export. Therefore, providing data on the biology of these plants is important for the country. Lallemantia royleana grows in different parts of Iran and forms several local populations. Genetic, morphological and biochemical divergence of geographical populations are well known in plant species. We have no report on population genetic structure, genetic fragmentation, local adaptation and gen flow of Lallemantia royleana populations in the country. Therefore, the present population genetics investigation was programmed to produce data on above said questions. Randomly collected plants of 7 geographical regions were studied by ISSR molecular markers. This information can be used in hybridization and gene conservation of this medicinal plant in Iran.

Open access

Zahra Barati and Mojgan Afkhami

Abstract

In this paper, we study the planar and outerplanar indices of some graphs associated to a commutative ring. We give a full characterization of these graphs with respect to their planar and outerplanar indices when R is a finite ring.

Open access

Elena Benito, Eufemia Varela and María Rodríguez-Alleres

Abstract

The primary purpose of this work was to assess the persistence of water repellency in the surface horizon of coarse-textured soils under natural Quercus robur ecosystems, and Pinus pinaster and Eucalyptus globulus plantations, in the northwest of the Iberian Peninsula. Water repellency was determined by applying the water drop penetration test (WDPT) to soil samples collected from variable depths (0–40 cm). Measurements were made on field-moist samples obtained at the end of the dry period and on samples dried at 25ºC in the air. All soils exhibited very high (severe to extreme) water repellency in the topmost soil layer (0–5 cm) but no significant differences among the three plant species studied. Extreme persistence was observed down to 20 cm in the soils under eucalyptus and down to 10 cm in those under pine. The soils under oak were those exhibiting the highest variability in water repellency and the greatest decrease in it with increasing depth (especially in relation to soils under eucalyptus).

Water repellency exhibited significant positive correlation with the C content and C/N ratio of the soils. Soil water repellency was similar in the air-dried samples and field-moist samples.

Open access

Ala Istratenco

Abstract

Chronic rhinosinusitis with nasal polyps (CRSwNP) is considered a multifactorial pathology with negative impact on the quality of life and considerable socio-economic effects. The pathogenesis of CRSwNP has not yet been fully elucidated despite remarkable studies in this field. This limits the pathogenic treatment and, therefore, the pathological process is expressed by a greater tendency of recurrence. Patients with recurrent CRSwNP remain in a severe state and therapeutically uncontrolled. In recent studies, the involvement of oxidative stress (OS) in the pathogenesis of CRSwNP has been more frequently mentioned. CRSwNP is considered a response of the sinonasal tissue on the inflammatory state, associated with OS and production of reactive oxygen species, causing injury to sinonasal tissues. It was demonstrated that the amount of ROS in the nasal polyp tissue corresponds to the severity of CRSwNP.

A literature review on the role of OS in the pathogenesis of CRSwNP was undertaken. The relevant information was identified using a search of electronic databases. Keywords used to highlight relevant papers were a combination of “chronic rhinosinusitis with nasal polyps” and “oxidative stress”.

This review demonstrates that there is a strong relationship between OS and CRSwNP pathogenesis. It is hypothesized that antioxidants may have a preventive role in CRSwNP. Nevertheless, additional research is required to further evaluate the effectiveness of antioxidant therapy.

Open access

T.S. Blyth and M.H. Almeida Santos

Abstract

We investigate the class BA of ordered regular semigroups in which each element has a biggest associate x = max {y | xyx = x}. This class properly contains the class PO of principally ordered regular semigroups (in which there exists x = max {y | xyx x}) and is properly contained in the class BI of ordered regular semigroups in which each element has a biggest inverse x◦. We show that several basic properties of the unary operation x x in PO extend to corresponding properties of the unary operation x x in BA. We consider naturally ordered semigroups in BA and prove that those that are orthodox contain a biggest idempotent. We determine the structure of some such semigroups in terms of a principal left ideal and a principal right ideal. We also characterise the completely simple members of BA. Finally, we consider the naturally ordered semigroups in BA that do not have a biggest idempotent.

Open access

Vlad Budu, Tatiana Decuseara, Ioan Alexandru Bulescu, Lavinia Ilinca and Alexandru Panfiloiu

Abstract

Inverted papilloma is a rare benign sinonasal tumor with a still unclear etiology. In the last decades, HPV implication in inverted papilloma etiopathogeny has been studied and demonstrated in some scientific research papers, but with no causality proven. Imagistic investigations and the Krouse classification establish the surgical approach. Endoscopic surgery represents the golden standard treatment for most cases of inverted papilloma, while external or combined approaches present limited indications.

The authors present a case and therapeutic plan of an inverted papilloma located in the ethmoid sinus, with origin in the lamina papyracea and high-risk HPV implication.