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Open access

Narjes Azizi, Masoud Sheidai, Valiollah Mozaffarian, Mitra Arman and Zahra Noormohammadi

Abstract

This study conducted to determine relationship among and within Iranian Helichrysum species (Asteraceae). In this study based on ISSR markers, the highest percentage of ISSR loci polymorphism (54.7%) occurred in H. armenium. The highest gene diversity over loci (1.224), Shannon’s Information Index (0.224%) and Expected Heterozygosity (0.142%) occurred in H. armenium (0.18) and the lowest of these parameters (0%) were observed in H. araxinum, H. graveolens, H. persicum and H. psychrophilum. The highest genetic similarity occurred between H. armenium and H. rubicundum (0.989), while the lowest was between H. polyphyllum and H. graveolens (0.213). The analysis of molecular variance (AMOVA), showed significant genetic variation among (24%) and within (76%) species. In morphological analysis traits such as indumentum, resting bud, achene length, achenial papillae, dimension of receptacle and form and apex of phyllaries were main diagnostic features. Results obtained from the morphological cluster were greatly consistent with the molecular data, to elucidating taxonomic relationships, as well as both attributed the higher diversity in H. armenium and H. rubicundum in comparison with other species and also indicated that H. persicum is a member of H. oocephalum species. Totally we confirmed the presence of 18 species in Iran.

Open access

Elena Nakvasina, Nadezhda Demina, Nadezhda Prozherina and Natalia Demidova

Abstract

Phenotypic plasticity of 22 spruce provenances in three test plots located in the European North of Russia was studied. Parent spruce stands are located within the Russian Plain and are represented by Picea abies (L.) Karst., P. obovata (Ledeb.) and two introgressive hybrids. In the test plots located in the middle and southern taiga subzones P. abies provenances are tested northward of its distribution area and P. obovata provenances are tested within the distribution area and nearby its boundaries. phenotypic plasticity of the spruce provenances was assessed. Straight-line regression coefficient based on survival, diameter, and height was calculated. All provenances are divided into two groups: plastic and non-plastic provenances. High plasticity is observed more often for P. abies and hybrids forms with properties of P. abies. Plastic provenances based on three parameters grow in the Leningrad, Pskov, Vologda, Kostroma and Karelia. Area of parent stands growing is quite small-size and lies between 56º30´ – 61º40´ N and 30º30´ – 42º30´ E. Adaptive provenances of P. obovata and its related hybrids forms grow in the North-Eastern part of the Russian Plain that could be consequence of its distribution in Holocene. Picea abies being the more adaptive species would be more responsive to climate changes in terms of survival and growth rate than P. obovata. Therefore, in case of sustainable climate warming in the Northern areas of the Russian Plain, the further propagation and major distribution of P. abies with further competitive replacement of P. obovata can be expected.

Open access

Jaime G. Cuevas, José L. Arumí and José Dörner

Abstract

Lagtimes and times of concentration are frequently determined parameters in hydrological design and greatly aid in understanding natural watershed dynamics. In unmonitored catchments, they are usually calculated using empirical or semiempirical equations developed in other studies, without critically considering where those equations were obtained and what basic assumptions they entailed. In this study, we determined the lagtimes (LT) between the middle point of rainfall events and the discharge peaks in a watershed characterized by volcanic soils and swamp forests in southern Chile. Our results were compared with calculations from 24 equations found in the literature. The mean LT for 100 episodes was 20 hours (ranging between 0.6–58.5 hours). Most formulae that only included physiographic predictors severely underestimated the mean LT, while those including the rainfall intensity or stream velocity showed better agreement with the average value. The duration of the rainfall events related significantly and positively with LTs. Thus, we accounted for varying LTs within the same watershed by including the rainfall duration in the equations that showed the best results, consequently improving our predictions. Izzard and velocity methods are recommended, and we suggest that lagtimes and times of concentration must be locally determined with hyetograph-hydrograph analyses, in addition to explicitly considering precipitation patterns.

Open access

Livio Poldini and Stefano Tasinazzo

Abstract

Recent original data concerning vineyard spring vegetation from Veneto hilly belt (North-eastern Italy) highlighted once again the phytogeographic originality of south-eastern territories with respect to Central European ones, also in anthropogenic coenosis. New relevés suggested to restate the association Cerastio tenoreani-Geranietum dissecti as vicarious vegetation of Geranio rotundifolii-Allietum vinealis occurring on the north side of the Alps. The comparison of autumn material from terracing vineyards of the sandy-marly Eocene flysch around Trieste coast with similar European relevés enabled to reject the not validly described Anagallido-Mercurialetum and to replace it with Mercurialetum annuae. In modern winegrowing Cerastio-Geranietum and Mercurialetum annuae are vanishing due to changing of agronomic schemes, as some relevés reported in the text document.

Open access

Abul Basar

Abstract

In this paper, we study the concept of ordered (m, n)-Г-hyperideals in an ordered LA-Г-semihypergroup. We show that if (S, Г, ◦,⩽) is a unitary ordered LA-Г-semihypergroup with zero 0 and satisfies the hypothesis that it contains no non-zero nilpotent (m, n)-Г-hyperideals and if R(L) is a 0-minimal right (left) Г-hyperideal of S, then either (R◦ Г ◦L] = {0} or (R◦ Г ◦ L] is a 0-minimal (m, n)-Г-hyperideal of S. Also, we prove that if (S, Г, ◦,⩽) is a unitary ordered LA-Г-semihypergroup; A is an (m, n)-Г-hyperideal of S and B is an (m, n)-Г-hyperideal of A such that B is idempotent, then B is an (m, n)-Г-hyperideal of S.

Open access

Saša Polović, Vanja Ljoljić Bilić, Ana Budimir, Darko Kontrec, Nives Galić and Ivan Kosalec

Abstract

Aroylhydrazones 1–13 were screened for antimicrobial and antibiofilm activities in vitro. N′-(2-hydroxy-phenylmethylidene)-3-pyridinecarbohydrazide (2), N′-(5-chloro-2-hydroxyphenyl-methylidene)-3-pyridinecarbohydrazide (10), N′-(3,5-chloro-2-hydroxyphenylmethylidene)-3-pyridinecarbohydrazide (11), and N′-(2-hydroxy-5-nitrophenylmethylidene)-3-pyridinecarbohydrazide (12) showed antibacterial activity against Escherichia coli, with MIC values (in µmol mL−1) of 0.18–0.23, 0.11–0.20, 0.16–0.17 and 0.35–0.37, resp. Compounds 11 and 12, as well as N′-(2-hydroxy-3-methoxyphenylmethylidene)-3-pyridinecarbohydrazide (6) and N′-(2-hydroxy-5- methoxyphenylmethylidene)-3-pyridinecarbohydrazide (8) showed antibacterial activity against Staphylococcus aureus, with the lowest MIC values of 0.005–0.2, 0.05–0.12, 0.06–0.48 and 0.17–0.99 µmol mL−1. N′-(2-hydroxy-5-methoxyphenylmethylidene)-3-pyridinecarbohydrazide (7) showed antifungal activity against both fluconazole resistant and susceptible C. albicans strains with IC 90 range of 0.18–0.1 µmol mL−1. Only compound 11 showed activity against C. albicans ATCC 10231 comparable to the activity of nystatin (the lowest MIC 4.0 ×10−2 vs. 1.7 × 10−2 µmol mL−1). Good activity regarding multi-resistant clinical strains was observed for compound 12 against MRSA strain (MIC 0.02 µmol mL−1) and compounds 2, 6 and 12 against ESBL+ E. coli MFBF 12794, with the lowest MIC for compound 12 (IC 50 0.16 µmol mL−1). Anti-biofilm activity was found for compounds 2 (MBFIC 0.015–0.02 µmol mL−1 against MRSA) and 12 (MBFIC 0.013 µmol mL−1 against EBSL+ E. coli). In the case of compound 2 against MRSA biofilm formation, MBFIC values were comparable to those of gentamicin sulphate, whereas in the case of compound 12 and EBSL+ E. coli even more favourable activity compared to gentamicin was observed.

Open access

Jacek Kotus, Tomasz Sowada, Michał Rzeszewski and Patrycja Mańkowska

Abstract

The article presents a discussion on the anatomy of place-making within the framework of the communication processes against the background of social order in a post-socialist city. The main aim of the text is to look at the social mechanisms of place-making processes “under the microscope”. The place-making activities are very often associated with planning and urban design. However, behind that planning veil is the social world of urban neighbourhood communities. In the article we propose, the social communication and participation processes are among the key factors responsible for creating urban spaces. We are presenting a place-making case study, using the example of Asnyk Square in Poznań. In this context, we are analysing social attitudes and social communication, which took place in the course of the place-making processes and influenced urban planning activities. The discussed case is complicated and provides no easy solutions.

Open access

Ilya Shegelman, Pavel Budnik, Vyacheslav Baklagin, Oleg Galaktionov, Ivan Khyunninen and Artem Popov

Abstract

Natural-production conditions determine operational efficiency of logging machines. This influence needs to be taken into account at different levels of forest management. It is necessary to allocate areas with similar natural-production conditions for effective forest management. It allows simplifying the decision making process for selecting logging technology and machines. The purpose of this study was to establish areas with similar natural and production conditions in the European North of Russia (ENR). In addition, for small enterprises, we recommend logging technologies and logging machines that can be used in established areas. We determined the indicators of the natural-production conditions of ENR regions and compared them. Cluster analysis was used to compare the indicators. We found that ENR can be divided into three main zones A, B, C and two subzones B1 and B2 with similar natural-production conditions. In the zones A, B and the subzones B1 and B2, small logging enterprises should use a harvester and a forwarder. In the zone C, the enterprises can use a logging system including a harvester and a forwarder or a logging system including a feller buncher, a skidder and a processor. The logging system should be based on the light class of logging machines for the zone A, the medium class or the heavy class for the zones B, C and the subzones B1, B2, the heavy class of machines for the zone C.

Open access

Igor Dakskobler and Livio Poldini

Abstract

We conducted a phytosociological study of alpine grasslands with dominant Luzula alpinopilosa in the Julian and Carnic Alps. Based on a comparison with similar communities elsewhere in the Alps we described a new association Junco jacquinii-Luzuletum alpinopilosae, which we classify into the provisional alliance Doronico glacialis-Juncion jacquinii, order Festucetalia spadiceae and class Juncetea trifidi. The new association characterises moist shady grasslands in gullies and on ledges on limestone admixed with marlstone and chert, in the elevation range between 2000 and 2500 m, where the snow cover persists for extended periods. We distinguish three subassociations: -galietosum anisophyllae (the most calcareous form), -potentilletosum aureae (typical form) and -leucanthemopsietosum alpinae (acidophilic form on Werfen sandstones in the Carnic Alps, which is the most similar to the stands of the association Luzuletum alpinopilosae from the Central Alps).

Open access

Hippolyte Hounnon and Klaus Denecke

Abstract

A variety of semirings is said to be solid if each of its identities is satisfied as hyperidentity. There are precisely four solid varieties of semirings. Each of them contains every derived algebra, where the both fundamental operations are replaced by arbitrary binary term operations. If a variety contains all linear derived algebras, where the fundamental operations are replaced by term operations induced by linear terms, it is called linear-solid. We prove that a variety of semirings is solid if and only if it is linear-solid.