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We test the hypothesis that climatic changes since 1800 have resulted in unrealized potential vegetation changes that represent a "climatic debt" for many ecosystems. Caledonian pinewoods, an EU priority forest type, are used as a model system to explore potential impacts of two centuries of climatic change upon sites of conservation importance and surrounding landscapes. Using methods that estima

A transmitter consisting of a voltage controlled oscillator (VCO) and power amplifier (PA) for the 400 MHz Medical Implanted Communication System band (MICS) was built in a standard 0.35-μm CMOS process. A push pull architecture was used for both the VCO and the PA. Two off-chip inductors were needed. The design was optimized for 400 μW output power at 3 V supply, which resulted in an efficiency o

Gas turbine maintenance is crucial due to high cost for the replacement of its components and associated loss of power during shutdown period. Conventional scheduled maintenance, based on equivalent operating hours, is not the best alternative as it can require unnecessary shut downs. Condition based maintenance is an attractive alternative as it decreases unnecessary shut downs and has other adva

Photosynthesis is the process through which the energy from the sun is converted into chemically bound energy stored in carbohydrates. Due to large variations in light intensities and stress situations, plants must be able to regulate the absorbed energy since excess energy would otherwise damage the plant. One of several photoprotective mechanisms involves the xanthophyll cycle. A copper binding

The carbon dynamics of northern natural ecosystems contribute significantly to the global carbon balance. Periodic disturbances to these dynamics include insect herbivory. Larvae of autumn and winter moths (Epirrita autumnata and Operophtera brumata) defoliate mountain birch (Betula pubescens) forests in northern Scandinavia cyclically every 9-10 years and occasionally (50-150 years) extreme popul

Aims: To study mortality rates among patients with diabetes and concomitant atrial fibrillation (AF), prescribed different cardiovascular drugs in primary health care. Methods: Study population consisted of men (n = 1319) and women (n = 1094) aged = >= 45 years from a database including 75 primary care centres in Sweden. Cox regression analysis, with hazard ratios (HRs), 95% confidence interval (9

Objectives Exposure to aluminium compounds, such as fluorides in gaseous and particulate form, places people who work in potrooms at risk for respiratory symptoms. Workers in potrooms, however, also are exposed to a number of other air contaminants. In this study, we present the first report of a dose-response relationship after exposure to potassium aluminium tetrafluoride (KAlF4) and the influen

Although the existence of a large carbon sink in terrestrial ecosystems is well-established, the drivers of this sink remain uncertain. It has been suggested that perturbations to forest demography caused by past land-use change, management, and natural disturbances may be causing a large component of current carbon uptake. Here we use a global compilation of forest age observations, combined wit

The springtime transition to regional-scale onset of photosynthesis and net ecosystem carbon uptake in boreal and tundra ecosystems are linked to the soil freeze-thaw state. We present evidence from diagnostic and inversion models constrained by satellite fluorescence and airborne CO2 from 2012 to 2014 indicating the timing and magnitude of spring carbon uptake in Alaska correlates with landscape

Atmospheric carbon dioxide enrichment (eCO2) can enhance plant carbon uptake and growth1–5, thereby providing an important negative feedback to climate change by slowing the rate of increase of the atmospheric CO2 concentration6. Although evidence gathered from young aggrading forests has generally indicated a strong CO2 fertilization effect on biomass growth3–5, it is unclear whether mature fores

Digital and scalable technologies are increasingly important for rapid and large-scale assessment and monitoring of land cover change. Until recently, little research has existed on how these technologies can be specifically applied to the monitoring of Reducing Emissions from Deforestation and Forest Degradation (REDD+) activities. Using the Google Earth Engine (GEE) cloud computing platform, we

The terrestrial carbon cycle is an important component of the global carbon budget due to its large gross exchangefluxes with the atmosphere and their sensitivity to climate change. Terrestrial biosphere models showlarge uncertainties in simulating carbon fluxes, which impact global carbon budget assessments. The land surfacecarbon cycle is tightly controlled by soil moisture through plant physiol