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Numerical simulation of fatty acids in lake sediments

The finite element model was successfully applied to predict the Pb-210 and total extractable fatty acid concentrations at different depths in two sediment cores from Lake Ontario by using different transport parameters. The transport parameters were computed from Pb-210 data. These parameters were used to simulate the total extractable fatty acid concentrations at different depths. The computed r

Spara, laga, bo : Husdrömmar i mäklarreklam från 1960-, 70- och 80-talet

I denna artikel ställer jag frågor till arkivmaterial ur vardagstrycket: ett antal mäklarbroschyrer och reklamutskick analyseras med fokus på husdrömmar. Vilka husdrömmar gestaltas? Vem antas bo här, hur, var och varför? Vem är husdrömmaren, vilken värld, tid, människa och bostadskultur framträder i materialet? Jag jämför material från 1970- och 1980-tal med slutsatser jag dragit i min forskning o

Pedagogiska problem och lösningar i pandemitid : En samling lärarberättelser

Covid-19-pandemin blev en global kris med konsekvenser för såväl offentliga och kollektiva som privata och individuella vardagspraktiker. Svenska universitet fick med kort varsel lägga om all undervisning så att den kunde utföras på distans. Bidragen i denna antologi består av en samling berättelser skrivna utifrån ett antal universitetslärares undervisningsvardag under en omvälvande tid. De repreA collection of teacher's stories about their pedagogical problems and solutions during the covid-19 pandemic

Discrepancy in responses to the surprise question between hemodialysis nurses and physicians, with focus on patient clinical characteristics : A comparative study

INTRODUCTION: The surprise question (SQ) "Would I be surprised if this patient died within the next xx months" can be used by different professions to foresee the need of serious illness conversations in patients approaching end of life. However, little is known about the different perspectives of nurses and physicians in responses to the SQ and factors influencing their appraisals. The aim was to

Ground-state heterogeneity and vibrational energy redistribution in bacterial phytochrome observed with femtosecond 2D IR spectroscopy

Phytochromes belong to a group of photoreceptor proteins containing a covalently bound biliverdin chromophore that inter-converts between two isomeric forms upon photoexcitation. The existence and stability of the photocycle products are largely determined by the protein sequence and the presence of conserved hydrogen-bonding interactions in the vicinity of the chromophore. The vibrational signatu

High-pressure tuning of primary photochemistry in bacterial photosynthesis : membrane-bound versus detergent-isolated reaction centers

While photosynthesis thrives at close to normal pressures and temperatures, it is presently well known that life is similarly commonplace in the hostile environments of the deep seas as well as around hydrothermal vents. It is thus imperative to understand how key biological processes perform under extreme conditions of high pressures and temperatures. Herein, comparative steady-state and picoseco

Mathematical models of wind induced circulation i a lake

Transient and stead y-state models for homogeneous and two-layered water masses are presented. The stationary models have been adapted to Lake Velen. The correspondencebetween theoretical and measured currents was good. A transport of momentum probably takesplace only where the thermocline touches the bottom. Knowledge of Ihe turbulent mechanismsis more important than the analytical approaches mad

High-Pressure Modulation of Primary Photosynthetic Reactions

Photochemical charge separation is key to biological solar energy conversion. Although many features of this highly quantum-efficient process have been described, others remain poorly understood. Herein, ultrafast fluorescence barospectroscopy is used for the first time to obtain insights into the mechanism of primary charge separation in a YM210W mutant bacterial reaction center under novel surro

Transient IR spectroscopy identifies key interactions and unravels new intermediates in the photocycle of a bacterial phytochrome

Phytochromes are photosensory proteins in plants, fungi, and bacteria, which detect red- and far-red light. They undergo a transition between the resting (Pr) and photoactivated (Pfr) states. In bacterial phytochromes, the Pr-to-Pfr transition is facilitated by two intermediate states, called Lumi-R and Meta-R. The molecular structures of the protein in these states are not known and the molecular

Fluorescence depolarization studies of heteroatom-doped CDs

In this work, we exploited time-resolved fluorescence polarization anisotropy (TRFA) to characterize un-doped and doped carbon dots (CDs). The rotational correlation time related to the size of the particle through classical Stokes-Einstein-Debye equation. The TRFA technique applied in this study achieves picoseconds time resolution, which approximately corresponds to the particle size determinati

Conclusions about turbulent exchange coefficients from model studies

Turbulent exchange coefficients are studied by field experiments and by mathematical models. The field experiments give a horizontal diffusivity of about 200 em'/s- The vertical exchange coefficient departs on the wind and is about 10 em'/s. Il has a maximum value a few metres below the surface and lends to fall to molecular values in the thermocline. Only where the thermocline is in contact with

Dynamic ratiometric imaging of cytosolic free Ca2+ in skeletal muscle cells using 340/385-nm light-emitting diode illuminators

Calcium-sensitive fluorescent indicators fall broadly into two categories, ratiometric (dual-wavelength) or single-wavelength indicators based on their response to a calcium elevation. Ratiometric indicators shift either their excitation or their emission wavelengths in response to calcium, allowing the concentration of intracellular calcium to be determined from the ratio of fluorescence emission

Spectral and kinetic effects accompanying the assembly of core complexes of Rhodobacter sphaeroides

In the present work, spectral and kinetic changes accompanying the assembly of the light-harvesting 1 (LH1) complex with the reaction center (RC) complex into monomeric RC-LH1 and dimeric RC-LH1-PufX core complexes of the photosynthetic purple bacterium Rhodobacter sphaeroides are systematically studied over the temperature range of 4.5–300 K. The samples were interrogated with a combination of op

Dimerization of core complexes as an efficient strategy for energy trapping in Rhodobacter sphaeroides

In the purple phototrophic bacterium Rhodobacter sphaeroides, light harvesting LH2 complexes transfer absorbed solar energy to RC-LH1-PufX core complexes, which are mainly found in the dimeric state. Many other purple phototrophs have monomeric core complexes and the basis for requiring dimeric cores is not fully established, so we analysed strains of Rba. sphaeroides that contain either native di

What Caregivers Like the Most (and Least) About Cognitive Behavioral Therapy for Youth Anxiety: A Mixed Methods Approach

Cognitive behavioral therapy (CBT) is an efficacious therapy for youth anxiety disorders. Caregivers are key stakeholders in youth therapy, and their feedback on treatment can help to inform intervention personalization. This mixed-methods study applied a systematic inductive thematic analysis to identify themes among most- and least-liked CBT features reported by caregivers using open-ended respo