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Various ecosystems, including shallow lakes, are suggested to possess alternative stable state dynamics. The response of such systems to environmental change is non-linear and not fully reversible, which calls for identification of feedback mechanisms and subtle changes connected to structural stability. Here, we used a 25-year data series on water chemistry to make inferences on processes prior t

Alarm systems are used in many situations, and should be as efficient as possible. In this thesis optimal predictive alarm systems, event predictors, are presented for general linear time series models with external signals. This family of process models include e.g. AR, ARMA, ARMAX and Box-Jenkins-type models. An optimal alarm system is characterized by having the least number of false alarms, fo

Increasing CO₂ emission is considered as the main reason for global warming in the world. One of the reasons for producing CO₂ is using of fossil-based materials in the construction projects. This study intends to assess the using bio-based materials instead of fossil-based materials for the thermal insulation layer of the external walls and roofs. Another focus of this project is using green conc

Introduction: Preoperative chemotherapy in early breast cancer increases the rate of breast preservation and provides prognostic information. Treatment decisions in these cases rely on biomarker assessments and subtyping from tissue acquired through core needle biopsies. Tumor heterogeneity and representativity are pit-falls when limited tissue is available. Biomarker expression may change conside

Terrestrial ecosystems have absorbed roughly 30 % of anthropogenic CO2 emissions over the past decades, but it is unclear whether this carbon (C) sink will endure into the future. Despite extensive modeling and experimental and observational studies, what fundamentally determines transient dynamics of terrestrial C storage under global change is still not very clear. Here we develop a new framewor

The Late Triassic time interval witnessed several important biological turnovers, extinctions and onset of new life forms. Therefore, it is crucial to better constrain the tectonic, climatic and oceanographic framework at this time. The radiogenic strontium isotopic composition (87Sr/86Sr) of seawater, recorded in marine carbonates is sensitive to variations in continental weathering and oceanic s

The method of angular- and wavelength-dispersive (e.g. two-dimensional) Rietveld refinement is a new and emerging tool for the analysis of neutron diffraction data measured at time-of-flight instruments with large area detectors. Following the approach for one-dimensional refinements (using either scattering angle or time of flight), the first step at each beam time cycle is the calibration of the

We show that Earth’s sedimentary strata can provide a record of the collisional evolution of the asteroid belt. From 1652 kg of pelagic Maiolica limestone of Berriasian–Hauterivian age from Italy, we recovered 108 extraterrestrial spinel grains (32–250 μm) representing relict minerals from coarse micrometeorites. Elemental and three oxygen isotope analyses were used to characterize the grains, pro

OBJECTIVE: To study cause specific mortality and cancer morbidity in workers exposed to the dust of grinding materials, grinding agents, and stainless steel, especially with regard to a possibly increased risk of respiratory, stomach, and colorectal cancer. METHODS: Retrospective cohort study, using reference cohorts of blue collar workers and population rates for comparison. The exposed cohort c

Popular Abstract in Swedish Snabba fenomen, som inträffar efter laserexcitation, har studerats med tidsupplöst röntgendiffraktion (TXRD). I de flesta experimenten har en ljuspuls från en femtosekundlaser använts för att excitera provet, och dynamiken har undersökts med röntgenljus. Tidsupplösta röntgendiffraktionsmätningar har utförts för att studera fasta halvledarmaterial, vätskor, ferro-elektriFast phenomena occurring after laser excitation were studied using time-resolved X-ray diffraction (TXRD). In most experiments, a femtosecond laser pulse was used to excite the sample, and X-rays were used as a probe. The X-ray diffraction technique was used to study bulk semiconductor samples, molten liquids, ferro-electric domain switching in potassium dihydrogen phosphate (KDP), and strain prop

Part of the justification for an integrated view of speech and gestures ( (( is their temporal coordination. Gestures generally coincide with or precede, but rarely follow lexical affiliate (McNeill, 1992). How synchrony impacts listeners remains less explored, despite potential relevance for video communication and virtual conversational agents. ERP studies suggest that temporal alignment affects