Search results

Filters

  • Journals
  • Authors
  • Contributor
  • Keywords
  • Date
  • Type

Search results

Number of results: 58
items per page: 25 50 75
Sort by:

Abstract

The basic idea of the paper is to apply a multi-attribute notion of diversityproposed by Nehring and Puppe to technological changes appearing as aconsequence of innovations in Schumpeter’s sense of the term in the productionsphere of the economy modelled by the use of the Arrow and Debreu topologicalapparatus. The paper is inspired by the work of Malawski and Woerter whoused Stirling diversity concept to prove that innovative processes are the sourceof growing diversity in the Schumpeterian vision of economic development. Weshow that, under certain conditions, nondecreasing multi-attribute diversity inthe production sphere of the private ownership economy is a necessary andsufficient condition for the occurrence of innovation in the economy under study.

Go to article
Download PDF Download RIS Download Bibtex

Abstract

We talk to Prof. Magda Konarska from the Centre of New Technologies at the University of Warsaw about the “spliceosome,” the ongoing need for basic research and the importance of diversity in science.

Go to article

Authors and Affiliations

Magda Konarska
Download PDF Download RIS Download Bibtex

Abstract

Failure to bring the perspective of women into scientific inquiry makes it incomplete, slower, and more costly, says Dr. Alicja Puścian from the Nencki Institute of Experimental Biology, Polish Academy of Sciences.
Go to article

Authors and Affiliations

Alicja Puścian
1

  1. Nencki Institute of Experimental Biology, Polish Academy of Sciences
Download PDF Download RIS Download Bibtex

Abstract

Species composition and density of Gastrotricha in bottom sediments were studied, on an annual basis, in the littoral of the mesotrophic Lake Piaseczno (Łęczyńsko-Włodawskie Lakeland). The number of species from spring to autumn remained on the same level (from 24 in spring to 22 in autumn), but in winter in littoral of the lake there were recorded only 8 species. Species diversity expressed by the Shannon index, in spring, summer and autumn was high and amounted 2.86; 2.69 and 2.77 respectively. In winter the value of the index was significantly lower and amounted 1.80. In individual seasons the mean density of Gastrotricha valued from 50 103 indiv. m-2 during winter to 1238 103 indiv. m-2 in spring. The density of Gastrotricha in spring was more than 24 times higher than that winter. There were no significant differences in species diversity Gastrotricha from spring to autumn, although the peak abundance was recorded in the spring. It is necessary to add, that the density of Gastrotricha during the spring peak was one order of magnitude higher from that in summer and autumn. The similarity of the fauna found in winter to the fauna occurring in other seasons, is significantly low, ranging from 24 to 27%. Seasonal changes in amount and diversity of the gastrotrich fauna are probably the result of temperature changes and food availability.
Go to article

Authors and Affiliations

Teresa Nesteruk
Download PDF Download RIS Download Bibtex

Abstract

Anthropogenic forms are important components of the Upper Silesian landscape. Among them, the slag and spoil dumps of coal, ferrous and non-ferrous metals, have an extraordinary aesthetic and document value - they provide evidence of the history of industrialization of this region. Waste rock accumulated in the dumping areas might be a source of utilizable material; thus the existence of most of the dumps is transitional phenomenon. However, a part of forms built from the rocks of low technical parameters have pretty big chance to remain. It happens in Western Europe that some of the dumps are left in the landscape as the evidence of history. They are usually spectacular objects treated as the natural monuments.
Go to article

Authors and Affiliations

Marzena Lamparska-Wieland
Jan Maciej Waga
Download PDF Download RIS Download Bibtex

Abstract

The diversity of cyanobacterial assemblages from various microhabitats in the Arctic area of Petuniabukta, Billefjorden, central Svalbard, was described. The present article contains the introductory common review of the cyanobacterial diversity and ecological data concerning main habitats, while the characteristics of individual taxonomic groups will be presented in following specific studies. Eight distinct main habitats were recognized, which differed in their species composition and especially the dominant species. More than 80 morphospecies were registered during our investigation, but only about 1/3 of them could be assigned to known and described taxa. The others require additional analyses based on modern taxonomic methods (the polyphasic approach ). The composition of cyanobacterial micro flora was comparable with assemblages in coastal Antarctica. The diversity of unicellular and colonial morphotypes (36 taxa) was higher tha n other groups. The number of filamentous species without heterocytes and akinetes, with 30 species, and heterocytous types, with only 20 species, were similar in both of these ecosystems. These numbers will be surely changed in the future, but the overall proportion of different groups will likely stay the same. In contrast to the limited species diversity, simple filamentous aheterocytous species were dominant and formed massive populations. Fewheterocy tous taxa, mostly grouped within the genus Nostoc ( N. commune –complex), were dominant in tundra soils.
Go to article

Authors and Affiliations

Jiří Komárek
Lubomír Kováčik
Josef Elster
Ondřej Komárek
Download PDF Download RIS Download Bibtex

Abstract

Celem pracy było określenie wpływu hydraulicznego czasu zatrzymania (H RT) i wydajności cyrkulacji wewnętrznej (Gel na różnorodność mikroorganizmów w biomasie unieruchomionej w porowatym nośniku ceramicznym. Bioreaktor, wykorzystywany do usuwania związków organicznych ze ścieków komunalnych, był eksploatowany przy HRT 70 i 60 min oraz qc w zakresie 20-70 drn"h'. Różnorodność mikroorganizmów była określana na podstawie wzorów RISA przy użyciu indeksu Shannona-Wienera (1-1'). Przy HRT równym 70 min, H' obniżył się z 2,48 ± 0,14 do 2,13 ± 0,23 ze wzrostem Ge z 20 do 60 drn+h'. Przy HRT 60 min. zwiększenie qc z 40 do 70 drnvh' spowodowało spadek 1-1' z 2,41 ± O, 13 do 2,08 ± O, 19. Przy każdej wartości HRT, najwyższą efektywność usuwania związków organicznych uzyskano przy najniższej wartości qc i najwyższej bioróżnorodności.
Go to article

Authors and Affiliations

Magdalena Zielińska
Agnieszka Cydzik-Kwiatkowska
Irena Wojnowska-Baryła
Download PDF Download RIS Download Bibtex

Abstract

The essay contains author’s reflections on the relationship between thinking and understanding as well as the role and significance of diversity, chance and egoism in human life and in shaping the social reality of the Homo sapiens species.
Go to article

Authors and Affiliations

Paweł Kisielow
1 2

  1. członek korespondent PAN
  2. Instytut Immunologii i Terapii Doświadczalnej im. Ludwika Hirszfelda PAN, Wrocław
Download PDF Download RIS Download Bibtex

Abstract

Sixty seven zooplankton taxa were recorded in a total of 5 WP-2 net vertical hauls carried out in a year round cycle in Admiralty Bay. Copepoda were the most common and abundant group and Oithona similis was the dominant species throughout the area. Polychaeta, Ostracoda and Chaetognatha were also rather common and abundant. Euphausiacea, Amphi-poda and Salpae occured mainly in the central part and the outlet area of the bay. No differences in zooplankton assemblages diversity in the four investigated areas of Admiralty Bay were en­countered. However, distinct differences in species richness between the zooplankton of Ezcurra Inlet and the main basin of the bay were observed. The composition of zooplankton was rather stable throughout the year, but seasonal occurrences of larvae of Polychaeta, Crustacea, Echino-dermata and Ascidiacea were noted. A Ust of the 174 zooplankton taxa ever found in Admiralty Bay is presented by combining the present results with the existing scientific data.

Go to article

Authors and Affiliations

Wojciech Kittel
Jacek Siciński
Maria I. Żmijewska
Luiza Bielecka
Katarzyna Błachowiak-Samołyk
Download PDF Download RIS Download Bibtex

Abstract

The shallow water benthic fauna was collected in Kongsfjord, West Spitsbergen. Sampling was conducted along two main environmental gradients: vertical gradient (depth 5–50 m) and horizontal gradient (sedimentation regime) along the fjord axis. A small rectangular dredge was used. Altogether 169 taxa were identified and four macrofaunal associations were distinguished. Bottom type and distance from the tidal glaciers seem to be the main factors responsible for species distribution. The Soft Bottom I Association occupying the fine mud of the Kongsbreen glacial bay consisted mostly of Crustacea with high dominance of scavenging amphipod Onisimus caricus. Bivalves prevailed in the Soft Bottom II Association, located further away from the main glacier outflows. The barren rocky shelf, deprived of vegetation by a sea urchin Strongylocentrotus droebachiensis was inhabited by the Rocky Shelf Association dominated by decapods. The last distinguished association (the Kelp Association) occurred on the hard bottom overgrown with macroalgae. The gastropod Margarites helicinus and amphipods Ischyrocerus spp. made up 60% of the individuals collected there.

Go to article

Authors and Affiliations

Honorata Kaczmarek
Maria Włodarska-Kowalczuk
Joanna Legeżyńska
ORCID: ORCID
Marek Zajączkowski
Download PDF Download RIS Download Bibtex

Abstract

Early blight disease caused by Alternaria sp. is one of the most devastating diseases of

Solanaceous crops widely distributed in Sudan. The aim of this study was to determine the

genetic variation among different Alternaria isolates recovered from different Solanaceae

crops showing typical symptoms of early blight disease. Infected leaves of tomato, potato,

eggplant and pepper were collected from different geographical zones in Sudan. The recovered

fungal isolates were identified to the genus level based on cultural and morphological

characteristics. Five representative isolates were sent to the CABI Bioscience, U.K. for confirmation.

The genetic relationship among the isolates was determined using the amplified

fragments length polymorphism (AFLP) technique and the generated data were used to

create similarity matrices using the PAST 3.01 software package. Dendrograms were constructed

based on Jaccard’s similarity coefficients. A total of 70 fungal isolates was recovered

from the tested plants and all of them showed morphological characteristics typical

of Alternaria spp. The conidia appeared in multiple-branched chains with spore sizes in

the range of 2.38−13.09 μm × 12.30−43.63 μm. Therefore, the isolates were identified as

Alternaria alternata (Fr.) Keissl. The identification was then confirmed by CABI.AFLPbased

dendrogram which revealed five clusters with a significant cophenetic correlation

coefficient (r = 0.834) between the dendrogram and the original similarity matrix irrespective

of their geographical origins. Eighteen (75%) of the Alternaria isolated from tomato

leaves were clustered together in cluster I and five isolates formed two separate clusters,

viz. cluster IV (T-Kh5 and T-H1) and cluster V (T-H4 and T-Med2). The remaining isolate,

T-Am5, grouped with one of the potato isolates in cluster III. The other isolates which were

recovered from potato, pepper and eggplants were all separated from the tomato isolates

in the largest cluster.

Go to article

Authors and Affiliations

Azza Siddig Abbo
Mohamed Osman Idris
Mustafa Ali Elballa
Ahmed Mohamed Hammad
Marmar Abdel Rahman El Siddig
Petr Karlovsky
Download PDF Download RIS Download Bibtex

Abstract

Antarctic pearlwort ( Colobanthus quitensis ) is one of the flowering plant species considered native to maritime Antarctica. Although the species was intensively analyzed towards its morphological, anatomical and physiological adaptation to local environment, its genetic variability is still poorly studied. In the presented study, a recently developed retrotransposon−based DNA marker system (inter Primer Binding Site – iPBS) was applied to assess the genetic diversity and differentiation of C. quitensis populations from King George Island (South Shetland Islands, West Antarctic). A total of 143 scoreable bands were detected using 7 iPBS primers among 122 plant specimens representing 8 populations. 55 (38.5%) bands were found polymorphic, with an average of 14.3% polymorphic fragments per primer. Nine of all observed fragments were represented as a private bands deployed unevenly among populations. Low genetic diversity (on average H e = 0.040 and I = 0.061) and moderate population differentiation (F ST = 0.164) characterize the analyzed material. Clustering based on PCoA revealed, that the populations located on the edges of the study area diverge from the central populations. The pattern of population differentiation corresponds well with their geographic location and the characteristics of the sampling sites. Due to the character of iPBS markers, the observed genetic variability of populations may be explained by the genome rearrangements caused by mobilization of mobile genetic elements in the response to various stress factors. Additionally, this study demonstrates the usefulness of iPBS markers for genetic diversity studies in wild species.
Go to article

Authors and Affiliations

Irena Giełwanowska
Piotr Androsiuk
Katarzyna Chwedorzewska
Kamil Szandar
Download PDF Download RIS Download Bibtex

Abstract

The archipelago of Svalbard in the European High Arctic lies on the convergence of the Palaearctic and Nearctic flora and fauna and contains elements of both regions. The island of Hopen is located in the south east of the archipelago within the path of the cold south−westerly flowing East Svalbard Current originating in the Arctic ocean and flowing along the north Russian coast. This current is postulated as a colonization route of the invertebrate fauna of Svalbard. Few reports of the terrestrial invertebrates of Hopen exist and none of the mite suborders Oribatida or Mesostigmata. With the taxonomic confusion existing in the inventories of this important region of the Arctic, new sampling campaigns with species identified by modern taxonomic principles and with material deposited in accessible museums and collections are essential. Identified mites included six species of oribatid mites with Diapterobates notatus dominating, and five species of Mesostigmata with Zercon forsslundi forming the dominant species. None of the species collected was a new record for Svalbard and all have wide circumpolar, Palaearctic or Holarctic distributions. Dispersal to Svalbard from northern Russia is hence neither supported nor rejected. The expected oribatid and mesostigmatid diversity of the island is greater than observed from the limited sampling described here.
Go to article

Authors and Affiliations

Stephen J. Coulson
Heinrich Schatz
Dariusz J. Gwiazdowicz
Torstein Solhøy
Download PDF Download RIS Download Bibtex

Abstract

Based on material collected during the BIOICE project off Iceland, the taxonomy and distribution of seventeen species (11 genera) of polychaetous annelids belonging to the family Ampharetidae (Annelida; Polychaeta) is reviewed. Eleven of these species were previously reported in the area or nearby areas: Amage auricula , Anobothrus gracilis , Glyp− hanostomum pallescens , Grubianella klugei , Lysippe fragilis , L. labiata , L. sexcirrata , L. vanelli , Samythella elongata, Sosane bathyalis and S. wireni . Five species, Amage benhami, Melinnampharete eoa, Noanelia hartmanae , Ymerana pteropoda and Zatsepinia rittichae , either never or only once reported after original description, are redescribed or discussed. A potentially new species, Amage sp., is described but not named because only one specimen is present. Several body characters of high taxonomic relevance in Ampharetidae are reviewed using SEM. The distribution of each species off Iceland is provided.
Go to article

Authors and Affiliations

Julio Parapar
Gudmundur V. Helgason
Igor Jirkov
Juan Moreira
Download PDF Download RIS Download Bibtex

Abstract

The concept of `diversity' has been one of the main open issues in the field of multiple classifier systems. In this paper we address a facet of diversity related to its effectiveness for ensemble construction, namely, explicitly using diversity measures for ensemble construction techniques based on the kind of overproduce and choose strategy known as ensemble pruning. Such a strategy consists of selecting the (hopefully) more accurate subset of classifiers out of an original, larger ensemble. Whereas several existing pruning methods use some combination of individual classifiers' accuracy and diversity, it is still unclear whether such an evaluation function is better than the bare estimate of ensemble accuracy. We empirically investigate this issue by comparing two evaluation functions in the context of ensemble pruning: the estimate of ensemble accuracy, and its linear combination with several well-known diversity measures. This can also be viewed as using diversity as a regularizer, as suggested by some authors. To this aim we use a pruning method based on forward selection, since it allows a direct comparison between different evaluation functions. Experiments on thirty-seven benchmark data sets, four diversity measures and three base classifiers provide evidence that using diversity measures for ensemble pruning can be advantageous over using only ensemble accuracy, and that diversity measures can act as regularizers in this context.

Go to article

Authors and Affiliations

Muhammad Atta Othman Ahmed
Luca Didaci
Bahram Lavi
Giorgio Fumera
Download PDF Download RIS Download Bibtex

Abstract

Stem canker and black scurf of potato (Solanum tuberosum L.) caused by Rhizoctonia solani Kühn are important and epidemic diseases in potato-growing regions worldwide, including Iran. In this study, 120 isolates were retrieved from infected stem canker from six potato- growing regions in Iran (Isfahan, Ardebil, Fars, Hamedan, Kurdestan and Kerman). Out of these, 30 isolates were selected as representatives for genetic and virulence analysis. The isolates were analyzed by one sequence analyzes of the ITS-rDNA region, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR), as well as virulence studies. Based on sequence analysis of the ITS-rDNA region, all 30 isolates were assigned to the anastomosis group (AG) and all were assigned to AG-3 PT. Cluster analysis using the unweighted pair group method with the arithmetic averages (UPGMA) method for both RAPD and ISSR markers revealed that they were divided into three main groups, with no correlation to geographical regions of the isolates. Pathogenicity tests showed that all isolates were pathogenic on potato cv. Agria; however, virulence variability was observed among the isolates. The grouping based on RAPD analysis and virulence variability was not correlated.

Go to article

Authors and Affiliations

Mehdi Nasr Esfahani
Download PDF Download RIS Download Bibtex

Abstract

The complete genome sequence of tomato leaf curl Palampur virus (ToLCPlV), that infects a papaya ( Carica papaya) plant, was determined. The virus genome was composed of 2,756 and 2,719 nucleotides (nt) in length, encoding all proteins required for replication, encapsidation and movement with the genome features typical of a bipartite begomovirus. Pairwise identity, derived using the Sequence Demarcation Tool (SDT), identified that the virus DNA A and DNA B shared maximum sequence identity 98–99% corresponding to the DNA A of ToLCPlV ([IR: Jir-T65X:08] JF501720) and 96–98% to the cognate partner DNA B of ToLCPlV ([IR: Jir1:T55P:07] FJ660423), respectively. The evolutionary relation using phylogenetic dendrograms of DNA A and DNA B genome components were clustered with ToLCPlV genomes of DNA A and DNA B of Iranian isolates. This study provides the first evidence of a bipartite ToLCPlV infecting papaya in the Sultanate of Oman and also indicates the requirement for more surveillance of this virus in Oman, as ToLCPlV is a major threat to tomato and other vegetable crops in South Asia (India and Pakistan) and in Iran.
Go to article

Authors and Affiliations

Muhammad Shafiq Shahid
1
Abdullah M. Al-Sadi
1

  1. Department of Plant Sciences, College of Agricultural and Marine Sciences, Sultan Qaboos University, Al-Khod, Oman
Download PDF Download RIS Download Bibtex

Abstract

Species of the genus Salsola belong to the family Chenopodiaceae and are associated with large saline areas in eastern Iran. The aim of the study was to isolate and characterize the endophytic and phytopathogenic fungal communities from non-mycotrophic Salsola species. Sampling was done from different parts of Salsola plants in the Birjand region in 2017 and 2018. Isolation and identification of fungal isolates were done using biological characteristics and ITS region sequences. The pathogenicity of the representative isolates was investigated by cultivating disinfected Salsola incanescens seeds under greenhouse conditions and inoculating seedlings with a fungal spore suspension from 7 day old fungal colonies on PDA media. Based on morphological and molecular data, 27 isolates from 11 fungal species were isolated and identified from Salsola tissues. Alternaria alternata, A. chlamydospora, Aspergillus terreus, Macrophomina phaseolina, Fusarium longipes, Ulocladium atrum, and Talaromyes pinophilus caused root or stem rotting and yellowing leaf of S. incanescens under greenhouse conditions. Aspergillus niger induced S. incanescens crown swelling without any pathogenicity. Clonostachys rosea, F. redolens and F. proliferatum grew as endophytic fungi on S. incanescens roots. This is the first report of phytopathogenic M. phaseolina, F. longipes, T. pinophilus, endophytic F. redolens and A. niger as a swelling agent on S. incanescens.

Go to article

Authors and Affiliations

Mina Razghandi
Abbas Mohammadi
Morteza Ghorbani
Mohammad Reza Mirzaee
Download PDF Download RIS Download Bibtex

Abstract

Genetic diversity manipulates a prime and vital role in the sustainable use of genetic resources. The data highlighted more insights into the genetic diversity of the arta plant ( Calligonum polygonoides subsp. comosum) populations collected from three localities, Qalabshu ( QQ), Mutubas ( MM) and Gamasa (GG), in Egypt as gene pool for biodiversity conservation and afforestation. Random amplified polymorphic DNA (RAPD) markers investigated the population pattern and structure. A total of 129-amplicons oscillated from 145 to 1505 bp and a total of 19-amplicons were specific markers with an average of nine bands for each population. The Shannon index (I) scored at an average of 0.3. The diversity ( h) oscillated from 0.11 to 0.25. The similarity matrices based on Jaccard coefficient recorded positive values. A higher correlation (r = 0.83) was between the combined Qalabshu (QQ) and Mutubas (MM) matrices using the Mantel test with 1,000 permutations. This species has higher adaptability for their regions. This gene pool is a valuable reservoir for enriching genetic diversity and provides basal information for the biodiversity conservation of a dominant species. The dominant species can be utilised in afforestation in the same region or another region which has the same environmental conditions.
Go to article

Authors and Affiliations

Ehab M.B. Mahdy
1
ORCID: ORCID
Rehab M. Rizk
2
ORCID: ORCID

  1. National Gene Bank (NGB), Agricultural Research Centre (ARC), 9 Gamaa St, P.O. Box 12619, Giza, Egypt
  2. Mansoura University, Faculty of Science, Botany Department, Mansoura, Egypt
Download PDF Download RIS Download Bibtex

Abstract

During laboratory and field experiments on Nacella concinna on the west coast of Admiralty Bay, King George Island (Antarctica) clear morphological and behavioural differences between two limpet forms (N. concinna polaris and N. concinna concinna) were found. They suggested presence of genetic divergence. AFLP (amplified fragment length polymorphism) profiling of N. concinna individuals representing the two forms revealed nearly 32% of polymorphic bands; only 2% of them differed between the forms. Our results suggest that the observed phenotypic variation seems to be a result of adaptation to environ− mental conditions and not of any genetic divergence.

Go to article

Authors and Affiliations

Katarzyna J. Chwedorzewska
Małgorzata Korczak
Piotr T. Bednarek
Marta Markowska-Potocka
Download PDF Download RIS Download Bibtex

Abstract

This paper present the data for monitoring forest conditions and forest resource management by a local community adjacent to the Doi Laung Wildlife Sanctuary, Huaimai Sub-district, Song District, Phrae Province, Thailand. This study uses quantitative forest surveys, interviews, discussions, and descriptions of the historical context of public participation in forest management including a detailed assessment of field conditions. The findings of a forest resources inventory show that (1) from the three sampled areas, Doi Laung Wildlife Sanctuary has highest richness, followed by village #16 and #14, and (2) Huaikhon #16 implied the process of framework to maintain a healthy condition and response to community needs with collective management. The conceptual model assessment that links key group indicators and drivers is presented based on previously developed assessment models. The framework focuses on the best way to provide forest management, forest fire prevention, and firefighting as well as monitoring of Check-dam construction and other activities that support the recovery of the forest community. This paper demonstrates the general of an environmental assessment framework to applying organize environmental information to facilitate policy decision making for the sustainable development.

Go to article

Authors and Affiliations

Piyapit Khonkaen
Jie-Dar Cheng
Download PDF Download RIS Download Bibtex

Abstract

Aeromonas hydrophila is a valuable indicator of the quality of water polluted by sewage and pathogens that pose a risk for humans and cold-blooded animals, including fi sh. The main aim of this research was to evaluate anthropogenic pollution of river water based on genetic diversity of 82 A. hydrophila strains by means of RAPD, semi-random AP-PCR (ISJ) and the rep-BOX conservative repeats test. Genetic diversity of A. hydrophila was HT = 0.28 (SD = 0.02) for all DNA markers (RAPD, semi random and rep-BOX). None of the analyzed electrophoretic patterns was identical, implying that there were many sources of strain transmission. The presence of genes for aerolysin (aerA), hemolysin (ahh1) and the cytotoxic enzyme complex (AHCYTOGEN) was verifi ed for all tested strains, and drug resistance patterns for tetracycline, enrofl oxacin and erythromycin were determined. The most diverse A. hydrophila strains isolated from river water were susceptible to enrofl oxacine (HS = 0.27), whereas less diverse strains were susceptible to erythromycin (HS = 0.24). The presence of the multidrug resistance marker (ISJ4-25; 1100 bp locus) in the examined strains (resistant to three analyzed drugs) indicates that intensive fi sh cultivation affects the microbiological quality of river water.
Go to article

Authors and Affiliations

A. Korzekwa
I. Gołaś
M. Harnisz

This page uses 'cookies'. Learn more