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Statistical inference with deep latent variable models

Finding a suitable way to represent information in a dataset is one of the fundamental problems in Artificial Inelegance. With limited labeled information, unsupervised learning algorithms help to discover useful representations. One of the applications of such models is imputation, where missing values are estimated by learning the underlying correlations in a dataset. This thesis explores two ofFinding a suitable way to represent information in a dataset is one of the fundamental problems in Artificial Intelligence. With limited labeled information, unsupervised learning algorithms help to discover useful representations. One of the applications of such models is imputation, where missing values are estimated by learning the underlying correlations in a dataset. This thesis explores two

Evidence for the production of three massive vector bosons with the ATLAS detector

A search for the production of three massive vector bosons in proton–proton collisions is performed using data at s=13 TeV recorded with the ATLAS detector at the Large Hadron Collider in the years 2015–2017, corresponding to an integrated luminosity of 79.8 fb−1. Events with two same-sign leptons ℓ (electrons or muons) and at least two reconstructed jets are selected to search for WWW→ℓνℓνqq. Eve

Not just fuel : energy stores are correlated with immune function and oxidative damage in a long-distance migrant.

In many animals, catabolic and anabolic periods are temporally separated. Migratory birds alternate energy expenditure during flight with energy accumulation during stopover. The size of the energy stores at stopover affects the decision to resume migration and thus the temporal organization of migration. We now provide data suggesting that it is not only the size of the energy stores per se that

Intraductal papillary mucinous carcinoma versus pancreatic ductal adenocarcinoma : A systematic review and meta-analysis

Background: Previous studies have indicated that there may be a difference in tumor biology between intraductal papillary mucinous carcinoma (IPMC) and pancreatic ductal adenocarcinoma (PDAC). However, the data are still controversial. The aim of this systematic review and meta-analysis was to summarize and compare the outcome of IPMC and PDAC after surgical resection. Methods: Studies comparing I

The microbial community size, structure, and process rates along natural gradients of soil salinity

Over 840 M ha of arable land is affected by salinization, and the area is predicted to increase due to global change. Assessments of the status of the microbial community in saline soils have frequently been based on microbial biomass estimates, which might not accurately reflect microbial process rates in soil. Moreover, assessments of how the relative importance of major decomposer groups bacter

Miocene restriction of the Pacific-North Atlantic throughflow strengthened Atlantic overturning circulation

Export of warm and salty waters from the Caribbean to the North Atlantic is an essential component of the Atlantic Meridional Overturning Circulation (AMOC). However, there was also an active AMOC during the Miocene, despite evidence for an open Central American Seaway (CAS) that would have allowed low-salinity Pacific waters to enter the Caribbean. To address this apparent contradiction and to co

Evaluating the contribution of forest ecosystem services to societal welfare through linking dynamic ecosystem modelling with economic valuation

Trade-offs exist among the multiple ecosystem services (ES) generated by forests. Generally, wood production conflicts with the provisioning of public-good ES such as the storage of carbon, nutrient retention and conservation of biodiversity. Recognizing that forests generate both private- and public-good ES implies that forestry should be optimized to maximize the contribution of forests to socie

Monthly gridded data product of northern wetland methane emissions based on upscaling eddy covariance observations

Natural wetlands constitute the largest and most uncertain source of methane (CH4) to the atmosphere and a large fraction of them are found in the northern latitudes. These emissions are typically estimated using process ("bottom-up") or inversion ("top-down") models. However, estimates from these two types of models are not independent of each other since the top-down estimates usually rely on th

Can we fly less? Evaluating the ‘necessity’ of air travel

Air travel is often justified as ‘necessary’ or ‘unavoidable’, in the sense that trips have purpose and value. Yet it is evident that people travel for reasons that may include forced and voluntary movement, with motives ranging from visiting friends and family, to leisure, or business. In light of the challenge to decarbonise transport, and the need to reduce greenhouse gas emissions, this paper

Global network of computational biology communities : ISCB's Regional Student Groups breaking barriers

Regional Student Groups (RSGs) of the International Society for Computational Biology Student Council (ISCB-SC) have been instrumental to connect computational biologists globally and to create more awareness about bioinformatics education. This article highlights the initiatives carried out by the RSGs both nationally and internationally to strengthen the present and future of the bioinformatics

The importance of migratory connectivity for global ocean policy

The distributions of migratory species in the ocean span local, national and international jurisdictions. Across these ecologically interconnected regions, migratory marine species interact with anthropogenic stressors throughout their lives. Migratory connectivity, the geographical linking of individuals and populations throughout their migratory cycles, influences how spatial and temporal dynami

Bacterial antibody hydrolyzing enzymes – as bacterial virulence factors and biotechnological tools

Antibodies are an essential part of the human immune system, and antibody mediated immunity has been an area of interest for many researchers for almost a century. An accumulation of knowledge regarding antibody structure, glycosylation and receptor interactions has contributed to the current understanding of antibody mediated immunity. It has more recently become evident how bacteria and other mi

Propylthiouracil-induced hypothyroidism in coho salmon, Oncorhynchus kisutch : Effects on plasma total thyroxine, total triiodothyronine, free thyroxine, and growth hormone

Thyroid hormones transiently increase during parr-smolt transformation in coho salmon, Oncorhynchus kisutch, and are believed to trigger morphological, physiological, behavioural, and neural changes. The effectiveness of propylthiouracil (PTU) to induce hypothyroidism in smolting coho salmon was determined by immersing coho salmon, Oncorhynchus kisutch, in 30 mg 1-1 PTU from May 1, two weeks prior

Free plasma thyroxine levels in coho salmon, Oncorhynchus kisutch, during parr-smolt transformation : Comparison with total thyroxine, total triiodothyronine, and growth hormone levels

Free plasma thyroxine (FT4) levels were measured in coho salmon, Oncorhynchus kisutch, during parr-smolt transformation (smoltification) using an equilibrium dialysis system followed by a radioimmunoassay. The FT4 data were correlated to total plasma thyroxine (TT4), triiodothyronine (TT3), and growth hormone (GH). Plasma samples were taken weekly from early April to late May, when the salmon wher

Developmental changes in the brain-stem serotonergic nuclei of teleost fish and neural plasticity

1. During early ontogeny, the serotonergic neurons in the brain stem of the three-spined stickleback shows a temporal and spatial developmental pattern that closely resembles that of amniotes. 2. However, in the adult fish, only the midline nuclei of the rostral group (dorsal and median raphe nuclei) and the dorsal lateral tegmental nucleus are consistently serotonin-immunoreactive (5-HTir), where

Distribution of serotonin-immunoreactive neurons in the brain of sockeye salmon fry

The organization of the serotonergic cell groups in the brainstem of fishes and amphibians has received relatively little attention. It has been generally assumed that they are little differentiated and constitute a median cell column throughout the brainstem, and that laterally migrated serotonergic cell groups are largely lacking. In the present study we present evidence to the contrary. By the

Ontogeny of GABA-immunoreactive neurons in the central nervous system in a teleost, Gasterosteus aculeatus L.

The inhibitory neurotransmitter γ-aminobutyric acid (GABA) is known to exert various neurotrophic actions in the developing nervous system, but little is known about its distribution in the central nervous system during early development. We have studied the development of GABA-immunoreactive (GABAir) neurons during embryogenesis of a teleost fish, the three-spined stickleback. As early as 51 h po

Ontogenetic development of serotoninergic neurons in the brain of a teleost, the three-spined stickleback. An immunohistochemical analysis

The ontogenetic development of serotoninergic neurons in the brain of the stickleback was investigated with the indirect immunocytochemical peroxidase-antiperoxidase technique, using a specific antibody to serotonin (5-hydroxytryptamine, 5-HT). Formation of neuronal populations takes place during embryonic development. By 80 h after fertilization, the first 5-HT perikarya have appeared in the vent