Holocene Sediment Magnetic Properties Along a Transect from Isafjardardjup to Djupall, Northwest Iceland

Holocene changes in terrestrial provenance and processes of sediment transport and deposition are tracked along a fjord-to-shelf transect adjacent to Vestfirdir, Iceland, using the magnetic properties ofmarine sediments.Magnetic susceptibility (MS) profiles of 10 cores (gravity and piston) were obtained onboard using a Bartington MS loop. Remanent magnetizations were measured at 1-cm intervals from u-channel samples taken from six cores on a cryogenic magnetometer. Between six and nine alternating field demagnetization steps were used to isolate the characteristic magnetization directions. The chronologies of the cores used in this study were determined from AMS14 C dates on mollusks and foraminifera and contrained by the regional occurrance ofthe 10,200 6 60 cal yr. BP Saksunavatn tepha. Correlative fluctuations in magneticconcentration are noted between the fjord and shelf sites, though these fluctuations are partiallymasked by regional variations in carbonate content. The onset of Neoglaciation is interpreted by changes in magnetic properties including an increase in mass magneticsusceptibility that began approximately 3000 cal yr. BP. The maximum angular deviation and the median destructive field (generally 20 mT) suggest that the natural remanent magnetization is carried by a coarse ferrimagnetite mineralogy, likely magnetite or titano-magnetite. Reproducible paleomagnetic inclination values are observed in several records, including a nearly vertical inclination around 8000 cal yr. BP, suggesting that the magnetic pole may have been proximal to Iceland, followed by an interval of much shallower inclination (6000–7000 cal yr. BP)

„Líður á þennan dýrðardag“ : successful aging and some thoughts on how more knowledge can have impact and improve social services for the elderly

Sérrit 2015 – Hlutverk og menntun þroskaþjálfaÖldruðum hefur fjölgað hér á landi eins og annars staðar í hinum vestræna heimi og almennt hefur heilsufar þeirra batnað. Með auknum fjölda eldra fólks og aukinni þekkingu á áhrifavöldum lífsgæða er þarft að kanna hvernig staða aldraðra birtist okkur hér á landi í byrjun 21. aldar. Umræða um aldraða í samfélaginu hefur á stundum verið nokkuð einsleit og neikvæð með áherslu á ýmsar aldurstengdar skerðingar og sjúkdóma. Í þessari grein eru lagðar aðrar áherslur, án þess þó að gera lítið úr þeim vandamálum sem vissulega er að finna hjá ákveðnum hópi eldri borgara. Markmið þessarar greinar er að veita yfirlit yfir rannsóknir sem fjalla um farsæla öldrun (e. successful aging). Kynntar eru skilgreiningar fræðimanna og rýnt í það sem þær eiga sameiginlegt, hvað greinir á milli og hvernig stuðla megi að farsælli öldrun. Auk fræðilegrar umfjöllunar verður litið á upplýsingar um álit aldraðra, sem aflað hefur verið á síðustu árum, á því hvað felist í farsælli öldrun. Gögn sem liggja þar til grundvallar eru svör einstaklinga við spurningum Þjóðminjasafns Íslands um þjóðhætti, ályktanir Félags sjúkraþjálfara frá árinu 2013 og loks nokkrar meistaraprófs- og bakkalársritgerðir sem fjalla um efnið. Þá verður sjónum beint að þroskaþjálfum sem unnið hafa á stofnunum sem veita öldruðum þjónustu og spurt hvað fagstétt þeirra geti lagt af mörkum til að stuðla að farsælli öldrun skjólstæðinga sinna. Gögn eru sótt í opinberar upplýsingar, bakkalárs- og meistaraprófsritgerðir auk viðtala sem höfundur hefur tekið við starfandi þroskaþjálfa. Breytt viðhorf setja nú mark sitt á þjónustu við aldraða og líta má á greinina sem innlegg í þá umræðu og þá þróun.The population grows older in many countries, also in Iceland, and the level of health among the elderly is rising, the elderly as a social group are getting older. With an growing number of older people and higher expectations regarding quality of life at the onset of the 21st cenury, it seems only appropriate to explore aging in Iceland. Public discussion about elderly people has often been narrow and negative with a focus on age-related deficiencies. This article takes a different perspective. Instead of highlighting deteriorating health and various curtailments, the article concentrates on successful aging. This is not meant to diminish the problems that many elderly people experience; rather, the aim of the article is to explore the concept of successful aging as defined by scholars, and discuss the characteristics of successful aging and ways to promote it. Perspectives of older people will be presented as well as those of social educators who provide institutional services for the elderly. The concept of successful aging, which first appeared in the middle of the last century, is examined in a historical and theoretical context. Various theories that explain and define successful aging are presented, although agreement about what the concept entails is lacking. Findings from a growing number of studies on successful aging, both international and Icelandic, are discussed; however, the lack of consensus of what constitutes successful aging inhibits their comparison. Special emphasis is given to Rowe and Kahn’s conceptualization of successful aging which identifies three fundamental conditions necessary for successful aging: avoiding disease and disability, retaining physical and mental skills, and being socially engaged and active. Perspectives of older people on successful aging and how to promote it were obtained through interviews and other qualitative methods. The elderly believe that negative stereotypes about aging and older people are harmful both to them and society. Problem-oriented media coverage plays a role in upholding the misconception that the elderly are unhappy, impoverished and helpless. Elderly people believe that this needs to be corrected and provide suggestions for ways to steer media coverage in a more positive direction. Attention is also drawn to research findings which show the important contribution to society made by the elderly in the form of assistance to their families, volunteering and more. Finally, the article presents findings from interviews with social educators working at various institutions that provide services to the elderly. They were asked to express their views on what can be done to increase the quality of life of elderly people. Today it is recognized that it is important to listen to the views of other professionals who work with the elderly regarding services for the elderly in addition to those working within the health care system. More emphasis is needed on the social and emotional needs of the elderly to enhance successful aging. Social educators possess knowledge and expertise which can be used to identify effective strategies that can benefit older people and enrich their lives. The purpose of obtaining diverse perspectives is to shed light on and increase our understanding of aspects which can contribute to a happier and more fulfilling life for people in their later years.Ritrýnd grei

Chitin synthases are critical for reproduction, molting, and digestion in the salmon louse (Lepeophtheirus salmonis)

Chitin synthase (CHS) is a large transmembrane enzyme that polymerizes Uridine diphosphate N-acetylglucosamine into chitin. The genomes of insects often encode two chitin synthases, CHS1 and CHS2. Their functional roles have been investigated in several insects: CHS1 is mainly responsible for synthesizing chitin in the cuticle and CHS2 in the midgut. Lepeophtheirus salmonis is an ectoparasitic copepod on salmonid fish, which causes significant economic losses in aquaculture. In the present study, the tissue-specific localization, expression, and functional role of L. salmonis chitin synthases, LsCHS1 and LsCHS2, were investigated. The expressions of LsCHS1 and LsCHS2 were found in oocytes, ovaries, intestine, and integument. Wheat germ agglutinin (WGA) chitin staining signals were detected in ovaries, oocytes, intestine, cuticle, and intestine in adult female L. salmonis. The functional roles of the LsCHSs were investigated using RNA interference (RNAi) to silence the expression of LsCHS1 and LsCHS2. Knockdown of LsCHS1 in pre-adult I lice resulted in lethal phenotypes with cuticle deformation and deformation of ovaries and oocytes in adult lice. RNAi knockdown of LsCHS2 in adult female L. salmonis affected digestion, damaged the gut microvilli, reduced muscular tissues around the gut, and affected offspring. The results demonstrate that both LsCHS1 and LsCHS2 are important for the survival and reproduction in L. salmonis.publishedVersio

Effects of chitin synthesis inhibitor treatment on Lepeophtheirus salmonis (Copepoda, Caligidae) larvae

The salmon louse (Lepeophtheirus salmonis) is an ectoparasite infecting Atlantic salmon (Salmo salar), which causes substantial problems to the salmon aquaculture and threatens wild salmon. Chitin synthesis inhibitors (CSIs) are used to control L. salmonis in aquaculture. CSIs act by interfering with chitin formation and molting. In the present study, we investigated the action of four CSIs: diflubenzuron (DFB), hexaflumuron (HX), lufenuron (LF), and teflubenzuron (TFB) on larval molt. As the mode of action of CSIs remains unknown, we selected key enzymes in chitin metabolism and investigated if CSI treatment influenced the transcriptional level of these genes. All four CSIs interfered with the nauplius II molt to copepodids in a dose-dependent manner. The EC50 values were 93.2 nM for diflubenzuron, 1.2 nM for hexaflumuron, 22.4 nM for lufenuron, and 11.7 nM for teflubenzuron. Of the investigated genes, only the transcriptional level of L. salmonis chitin synthase 1 decreased significantly in hexaflumuron and diflubenzuron-treated larvae. All the tested CSIs affected the molt of nauplius II L. salmonis larvae but at different concentrations. The larvae were most sensitive to hexaflumuron and less sensitive to diflubenzuron. None of the CSIs applied had a strong impact on the transcriptional level of chitin synthesis or chitinases genes in L. salmonis. Further research is necessary to get more knowledge of the nature of the inhibition of CSI and may require methods such as studies of protein structure and enzymological studies.publishedVersio

Deep Learning for Predicting Metastasis on Melanoma WSIs

Northern Europe has the second highest mortality rate of melanoma globally. In 2020, the mortality rate of melanoma rose to 1.9 per 100 000 habitants. Melanoma prognosis is based on a pathologist's subjective visual analysis of the patient's tumor. This methodology is heavily time-consuming, and the prognosis variability among experts is notable, drastically jeopardizing its reproducibility. Thus, the need for faster and more reproducible methods arises. Machine learning has paved its way into digital pathology, but so far, most contributions are on localization, segmentation, and diagnostics, with little emphasis on prognostics. This paper presents a convolutional neural network (CNN) method based on VGG16 to predict melanoma prognosis as the presence of metastasis within five years. Patches are extracted from regions of interest from Whole Slide Images (WSIs) at different magnification levels used in model training and validation. Results infer that utilizing WSI patches at 20x magnification level has the best performance, with an F1 score of 0.7667 and an AUC of 0.81

Trace metal distributions in sulfide scales of the seawater-dominated Reykjanes geothermal system: Constraints on sub-seafloor hydrothermal mineralizing processes and metal fluxes

Highlights • Predictable trace element enrichments and depletions in the Reykjanes system. • Boiling exerts a major influence on the enrichment of metals. • High concentrations of Au and Ag and Pb indicate accumulation in reservoir fluids. • Three quarters of the metal budget is deposited at depth or in the upflow zone. Abstract Mineral precipitation in the seawater-dominated Reykjanes geothermal system on the Mid-Atlantic Ridge, Iceland is caused by abrupt, artificially induced, pressure and temperature changes as deep high-temperature liquids are drawn from reservoir rocks up through the geothermal wells. Sulfide scales within these wells represent a complete profile of mineral precipitation through a seafloor hydrothermal system, from the deep reservoir to the low-temperature silica-rich surface discharge. Mineral scales have formed under a range of conditions from high pressures and temperatures at depth (>2 km) to boiling conditions in the upflow zone and at the surface. Consistent trace element enrichments, similar to those in black smoker chimneys, are documented: Cu, Zn, Cd, Co, Te, V, Ni, Mo, W, Sn, Fe and S are enriched at higher pressures and temperatures in the deepest scales, Zn and Cu, Bi, Pb, Ag, As, Sb, Ga, Hg, Tl, U, and Th are enriched at lower temperatures and pressures nearer to the surface. A number of elements (e.g., Co, Se, Cd, Zn, Cu, and Au) are deposited in both high- and low-pressure scales, but are hosted by distinctly different minerals. Other trace elements, such as Pb, Ag, and Ga, are strongly partitioned into low-temperature minerals, such as galena (Pb, Ag) and clays (Ga). Boiling and destabilization of metal-bearing aqueous complexes are the dominant control on the deposition of most metals (particularly Au). Other metals (e.g., Cu and Se) may also have been transported in the vapor phase. Very large enrichments of Au, Ag and Pb in the scales (e.g., 948 ppm Au, 23,200 ppm Ag, and 18.8 wt.% Pb) versus average concentrations in black smoker chimneys likely reflect that some elements are preferentially deposited in boiling systems. A mass accumulation of 5.7 t/yr of massive sulfide was calculated for one high-temperature production well, equating to metal fluxes of 1.7 t/yr Zn, 0.3 t/yr Cu, 23 kg/yr Pb, 4.1 kg/yr Ag, and 0.5 kg/yr Au. At least three quarters of the major and trace element load is precipitated within the well before reaching the surface. We suggest that a similar proportion of metals may be deposited below the seafloor in submarine hydrothermal systems where significant boiling has occurred. Mass accumulation estimations over the lifetime of the Reykjanes system may indicate significant enrichment of Zn, Pb, Au, and Ag relative to both modern and ancient mafic-dominated seafloor massive sulfide deposits, and highlights the potential for metal enrichment and accumulation in the deep parts of geothermal systems

Learning to live with social-ecological complexity : An interpretive analysis of learning in 11 UNESCO Biosphere Reserves

Unidad de excelencia María de Maeztu MdM-2015-0552Learning is considered a means to achieve sustainability in practice and has become a prominent goal of sustainability interventions. In this paper we explore how learning for sustainability is shaped by meaning, interpretation and experience, in the context of UNESCO Biosphere Reserves (BRs). The World Network of Biosphere Reserves brings environmental conservation, socio-economic development and research together in 'learning sites for sustainable development.' The World Network is globally significant, with 669 BRs in 120 countries, but as with many paradigmatic sustainability interventions BRs are perceived to suffer from a 'concept-reality gap.' We explore this gap from an interpretive perspective, focusing on participant interpretations of the meaning of BRs and their experiences of working with the concept - with the aim of painting a richer picture of learning for sustainability and the ways in which BRs might fulfil their role as learning sites. We provide a cross-case analysis of learning in 11 BRs around the world, drawing on interviews with 177 participants, and ask: How is the BR concept interpreted and enacted by people involved with BR work? What learning emerges through BR work, as described by those involved? We find that the BR concept is interpreted differently in each location, producing distinct expectations, practices and institutional designs. Learning occurs around common themes - human-environment relationships, actors and governance arrangements, and skills to navigate BR work - but is expressed very differently in each BR. The position of BRs 'in between' social, ecological and economic goals; local places and global networks; and government, private and civil society sectors, provides a valuable space for participants to learn to live with social-ecological complexity. We discuss our results in terms of their contribution to three pressing concerns in sustainability science: (i) power and politics in learning for sustainability, (ii) intermediaries and bridging organizations in multi-level governance, and (iii) reflexivity and knowledge-action relationships. Our comparative hermeneutic approach makes a novel methodological contribution to interpretive studies of sustainability policy and governance