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Daylight compliance of Swedish residential blocks according to past and current performance criteria

The importance of daylight to occupants’ health and wellbeing has been extensively documented, as well as its role in reducing electric lighting use. As a result, most countries have today some form of regulatory framework, specifying minimum daylight requirements for built spaces. The present Swedish building code (BBR – BFS 2011:6) includes general recommendations for daylight provision of resid

Regulator of G-protein signaling 5 regulates the shift from perivascular to parenchymal pericytes in the chronic phase after stroke

Poststroke recovery requires multiple repair mechanisms, including vascular remodeling and blood-brain barrier (BBB) restoration. Brain pericytes are essential for BBB repair and angiogenesis after stroke, but they also give rise to scar-forming platelet-derived growth factor receptor β (PDGFR-β)–expressing cells. However, many of the molecular mechanisms underlying this pericyte response after st

Tool Life and Cutting Data Modelling in Metal Cutting : Testing, Modelling and Cost Performance

One of the most important production processes in industry is metal cutting. If a product is not a machined metal part, it is likely that the mould, die and tools used to produce the product or parts of the product are machined. The tools, machines and time spent add to the cost of the finished product and both industry and academia spend considerable effort in increasing efficacy and minimizing t

Early-holocene vegetation of northern Iceland : Pollen and plant macrofossil evidence from the Skagi peninsula

Pollen and plant macrofossil records from two lakes on northernmost Skagi peninsula, northern Iceland, reflect a progressive closing of the vegetation cover during the early Holocene. This development was connected with the succession from an initial herb-tundra phase characterized by Oxyria digyna, Poaceae and Caryophyllaceae, through an intermediate dwarf-shrub phase dominated by Salix and Empet

Biostratigraphic Evidence of the Allerød-Younger Dryas-Preboreal Oscillation in Northern Iceland

Basal sediments of Lake Torfadalsvatn, northern Iceland, record changes in terrestrial and limnic environments in the period 11,300-9000 14C yr B.P. These changes were probably forced by climate and connected with displacements of the marine polar front and sea-ice margin. Pollen, spores, green algae (Pediastrum), saturation isothermal remanent magnetization, and carbon content of the basal sedime

Dynamic sea-level change during the last deglaciation of northern Iceland

A detailed reconstruction of deglacial relative sea-level changes at the northern coast of Iceland, based on the litho- and biostratigraphy of lake basins, indicates an overall fall in relative sea level of about 45 m between 11 300 and 9100 BP, corresponding to an isostatic rebound of 77 m. The overall regression was interrupted by two minor transgressions during the late Younger Dryas and in ear

Leaf metabolic and morphological responses of dwarf willow (Salix herbacea) in the sub-arctic to the past 9000 years of global environmental change

Ice-core records of the concentration of atmospheric CO2 and its stable isotope ratio (δ13C(a)) have shown that the global C cycle has not remained in steady-state over the past 11000 yr, implying a possible change in vegetation activity over this period. Here we evaluated the ecophysiological responses of the dwarf willow (Salix herbacea) over the past 9000 yr by measuring the stable carbon isoto

Plant survival in Iceland during periods of glaciation?

Aim: The paper addresses the classical question of possible plant survival in Iceland during the last glacial period in the light of a palaeobotanical record from northern Iceland, spanning the period 11,300-9000 BP, including the Younger Dryas stadial. We review the Late Cenozoic fossil plant record, the past debate on glacial plant refugia in Iceland, and the evidence for ice-free areas during t

What can be learned from practical cases of green economy? –studies from five European countries

The transition to green economies has been mediated by concrete cases and experiments in a variety of different industrial and social sectors. What is lacking, is research that would synthesize key findings and “lessons learned” across a variety of cases. In this study, we explore ten cases of green economy of different sectors and approaches from five European countries and identify factors that

The Preboreal oscillation around the Nordic Seas : Terrestrial and lacustrine responses

The occurrence of an early Preboreal climatic cooling/oscillation (PBO) in lacustrine and glacial records from northwest Europe, Iceland and Greenland is reviewed and documented. The often subtle response of the proxy records to this oscillation, in combination with its short duration, make it difficult to detect. Owing to its chronostratigraphic position between the 10000-9900 and 9600-9500 14C p

Neglected Values of Major Water Engineering Projects: Ecosystem Services, Social Impacts, and Economic Valuation

Major water infrastructure projects like dams can provide substantial benefits such as food and drinking water security, hydropower generation, and flood control. But these benefits may come at a (too) high cost of large scale ecological alterations or adverse social impacts such as involuntary resettlements. If these costs are neglected, an investment decision will hardly be efficient. In this ch

Green economy and related concepts : An overview

For the last ten years, the notion of a green economy has become increasingly attractive to policy makers. However, green economy covers a lot of diverse concepts and its links with sustainability are not always clear. In this article, we focus on definitions of green economy and related concepts and an evaluation of these concepts against the criterion of strong and weak sustainability. The artic

Variations in the carbon isotope composition of late-Holocene plant macrofossils : A comparison of whole-leaf and cellulose trends

Stable carbon isotope measurements (δ13C) made on Quaternary sequences of terrestrial plant subfossils are frequently used to infer palaeoclimatic trends. However, differential decomposition of individual constituents during incorporation of plant material into lake sediments could influence these interpretations. Therefore, we investigated down-core variations in the carbon isotope composition (δ

A holocene CO2 record from the stomatal index of subfossil Salix herbacea L. leaves from northern Sweden

A stomatal-based method of palaeo-CO2 estimation has been applied to a temporally detailed sequence of leaves from a high-latitude lake (68°N) in northern Sweden spanning the last 9000 years. The resulting atmospheric CO2 reconstruction documents the onset of a gradual increase c. 5000 years before present indicating that the carbon cycle has not been in steady state over this time. Stable carbon

Plant macrofossil methods and studies : CO2 Reconstruction from Fossil Leaves

This article provides a review of the application of stomatal frequency analysis to fossil leaves in the reconstruction of past atmospheric CO2 concentrations. It presents the physiological basis of the method, an overview of its application to leaves of Quaternary age, and an assessment of its potential and limitations. It also includes a description of the successive stages in a stomatal frequen