Low virus to prokaryote ratios in the cold: benthic viruses and prokaryotes in a subpolar marine ecosystem (Hornsund, Svalbard)

The density and spatial distribution of benthic viruses and prokaryotes in relation to biotic and abioticfactors were investigated in sediment cores collected in Hornsund, a permanently cold fjord on the West coast of Svalbard,Norway. The cores were obtained from the mouth of the fjord to the central basin, along a longitudinal transect. Theresults of our analyses showed lower densities of viruses (0.2 × 108 to 5.4 × 108 virus-like particles/g) and lower virus-toprokaryoteratios (0.2-0.6, with the exception of the uppermost layer in the central basin, where the ratio was about 1.2)at the study site than generally found in the temperate areas, despite the relatively high organic matter content in subpolarsediments. Variations in benthic viral and prokaryote abundances along gradients of particle sedimentation rates, phytopigmentconcentrations, and macrobenthic species composition together suggested the influence of particle sedimentationand macrobenthic bioturbation on the abundance and spatial distribution of prokaryotes and viruses in cold habitats. [IntMicrobiol 2013; 16(1):45-52

Hermit crabs (Pagurus spp.) at their northernmost range: distribution, abundance and shell use in the European Arctic

Hermit crabs are important components of Arctic benthic systems, yet baseline data on their densities and distribution patterns in this rapidly changing region are still scarce. Here we compile results of numerous research expeditions to Svalbard, the Barents Sea and northern Norway that were carried out from 1979 to 2011 by the Institute of Oceanology, Polish Academy of Sciences. The diversity of hermit crabs at the northern edge of their occurrence is very low; in Svalbard waters only one species (Pagurus pubescens) was detected. Another species (P. bernhardus), found in northern mainland Norway, north of the Arctic Circle, is likely to extend its distribution northward as the climate warms. Where the two species co-occur, competition between them probably accounts for the smaller sizes and poorer quality shells used by P. pubescens. The composition of the mollusc shells inhabited by these crabs differs between northern Norway and Svalbard, reflecting local mollusc species pools. Hermit crab densities were significantly higher than previously reported (max. mean 10 ind. m−2), suggesting their increasing level of dominance in benthic communities in the studied areas. The first to report the distribution of hermit crabs among habitats, this study showed that most individuals occurred at shallow depths (5–150 m), away from glacier termini and on hard bedrock rather than on soft substrata

Assessment of the morphology, microstructure, stereometric and tribological properties of Al2O3 surface layers produced electrolytically with the alternating current method in the presence of molybdenum disulfide

Dry friction tests were performed using a pin-on-plate tribological tester. In this study, Al2O3 and Al2O3 with MoS2 admixture plate with PEEK/BG pin. Plate surfaces were created using the constant current method and the non-periodic alternating current method. The dimension of Al2O3 fibers walls were calculate based on SEM micrographs. SGP measurements of the oxide layers were made by a Taylor Hobson Talysurf 2D pin profilometer. It was found that the gradient structure favors the reduction of the friction coefficient and weight loss of PEEK/BG in the tested friction pairs, and the method of gradually reducing non-periodic alternating current allowed to obtain a more homogeneous microstructure of aluminum oxide. The use of high current densities at the beginning of the process leads to the production of non-gradient coatings characterized by higher SGP amplitude parameters. This property translates directly into higher wear of the sliding PEEK/BG material and higher values of the friction coefficients of the tribological pairs thus obtained. The research also identified a strong correlation between the friction coefficient μ and surface topography parameters before the tribological cooperation of PEEK/BG pairs - Al2O3 oxide coating

A huge biocatalytic filter in the centre of Barents Sea shelf?

A primary production model for the Barents Sea shows a hot spot of organic carbon settlement to the sea bed over 100 km long, a shallow pile of highly permeable sediments (mainly large Balanus, Mya and Pecten shell fragments over 1 cm in size) of glacial origin. Hydrodynamic flow models suggest an intensive, deep flow of near-bottom waters into the sediment. Depending on wave height, water in shallow (30 m depth) places may percolate more than 5 m into the sediment. During 10 days of stormy weather as much as 4 to 8 kg wet weight pelagic biomass can be processed per square metre through this extremely permeable sediment. Analogous processes known in coastal waters lead to intense biocatalytic phenomena and metabolism of organic carbon within the seabed, estimated here as more intense than surface consumption. Spitsbergenbanken may be acting as a huge sink for organic carbon and an important source of nutrients in one of the most productive areas of the North Atlantic

Dysfunctions in the Mature Dendritic Cells Are Associated with the Presence of Metastases of Colorectal Cancer in the Surrounding Lymph Nodes

Dendritic cells play a key role in the antigen presentation and T cell activation. The aim of this study was a detailed analysis of the presence of mature dendritic cells (CD 83 positive) in colorectal cancer in correlation with selected clinicopathological parameters. The presence of mature dendritic cells (mDCs) was determined immunohistochemically using the anti-CD83 antibody. The morphometric analysis of the mDCs was performed in the normal colon wall adjacent to the cancerous tumor as well as in the front of the tumor and in the main mass of the cancerous tumor. Decrease in mDCs in the front and in the main tumor mass was observed. The increase in the number of mDCs in both of these locations was associated with the presence of metastases in the nearby lymph nodes (p<0.05 and p<0.01). Furthermore, the increase in the proportion of mDCs in the main tumor mass was associated with the presence of the invasion of tumor cells into the blood and lymph vessels (p<0.01). The increase in the amount of mDCs in the cancerous tumor is associated with the invasiveness of the tumor and especially with the metastasis to the surrounding lymph nodes

Zagrożenia zdrowotne wśród dzieci i młodzieży. T. 1

Praca recenzowana / Peer-reviewed pape

WhatsApp iconology : narratives on in-app photographic practices in (transnational) family communication

Sharing photographs and photo-chatting are common practices in doing family at a distance. This study looks at the processes of the production and circulation of photographs within the family network, analysing participants’ narratives about their image-based communication in WhatsApp. The data was collected as an ethnographic enquiry into the digitally mediated (transnational) family communication of five Polish women and their children living in Finland. It consists of five auto-driven visual elicitation interviews with an interactive collage, three elicitation interviews, with the participant’s smartphone used for fast reference to their in-app chats, and one semi-structured interview. The in-app photographs are explored as ‘imagetext’, that is, visual and verbal representations that create the WhatsApp ‘iconology’ of family visual communication. In participants’ narratives, photographs are regarded as an obligation (always to be sent to somebody), evidence (of being somewhere or achieving something), or a form of visual co-presence with living-apart relatives. Photo-chatting entertains (images of pets), provides expertise (snaps of medication), or is used to show off (photos taken at competitions). Photo-chatting helps to maintain family relationships by showing affection, comforting, and caring over a distance.peerReviewe

Virtual proximity and transnational familyhood : a case study of the digital communication practices of Poles living in Finland

The article presents a study of five Polish multicultural and multilingual families in Finland, and their engagement in digitally mediated family communication. Explored through an ethnographic inquiry into the in-app communication practices of Polish migrant mothers and children, the study contributes to the body of research at the intersection of new media and communication, transnational family and migration studies, and family multilingualism. Building on the concept of virtual proximity, which refers to the emotional closeness between individuals afforded by digital technologies and mobile communication, the study identifies four thematic patterns in participants’ practices in digital habitats: (i) children’s agency in creating family WhatsApp groups, (ii) the use of family in-app communication for language learning purposes, (iii) digital caregiving strategies and arrangements, and (iv) the use of digital photo-sharing as a form of visual co-presence. Children’s and mothers’ practices in digitally mediated communication differ from each other, but they lead to the formation of transnational familyhood in digital habitats. In this context, achieving virtual proximity by digital means helps to fulfil aspirations to remain a family across distance.peerReviewe

Performing transnational family with the affordances of mobile apps : a case study of Polish mothers living in Finland

Affordances provided by digital technologies and mobile apps (WhatsApp, Skype, Messenger) help in maintaining familyhood. These mobile apps enable the creation of in-app family groups. They also afford image sharing, which is used for phatic purposes. Digital connectivity provides the illusions of togetherness and belonging, and allows for performing family in a transnational context (emotional transnationalism). However, it also generates the feelings of guilt through infrequent communication. In the auto-driven visual elicitation interviews, the study looks at family constellations and technologically mediated communication from the perspective of five Polish mothers living in Finland. Applying the technique of an interactive collage, participants visualised kinship relations, using colourful cards showing silhouettes of adults and children and icons of mobile apps. The findings reveal complexities in digitally mediated familyhood, performed in the polymedia environment and determined by technological affordances.peerReviewe

What’s in the family app? : Making sense of digitally mediated communication within multilingual families

Communication within contemporary families is increasingly and to a significant extent mediated through technological devices and digital applications. Although the everyday reality of many multilingual families is permeated by technology, research on their digital and language practices has been scant. This article argues for the need for eclectic approaches that draw upon theories, practices, and findings from research on transnational families and migration, digitally mediated family communication, parental mediation, multilingualism online, and family multilingualism and language transmission. Two empirical case studies are presented on multilingual family constellations in Finland in which the instant messaging application WhatsApp was used to create space to sustain transnational family relationships, to negotiate about agency, to create cultural identity and group membership, as well as to practise and develop literacy. Whereas previous research has focused on digital practices in families, on multilingual practices on internet platforms, or on language transmission processes in families, we argue that future research should focus more on the digital multilingual family and explore the role of languages as embedded in digital media activities and interwoven in everyday family life.peerReviewe