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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

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

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

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

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

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

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

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

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

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

In this study, we use the photosynthetic purple bacterium Rhodobacter sphaeroides to find out how the acclimation of photosynthetic apparatus to growth conditions influences the rates of energy migration toward the reaction center traps and the efficiency of charge separation at the reaction centers. To answer these questions we measured the spectral and picosecond kinetic fluorescence responses a

Transparent indium tin oxides (ITO) electrodes were patterned using flash lamp pumped Q-switched Nd: YAG laser ablation technique. The Optical microscopy, atomic force microscopy and energy dispersive x-ray spectrum along with scanning electron microscope analysis shows the depth and width of the ablated area and the elements available in the ablated area. In-plane switching liquid crystal display

The snowmelt at a point is estimated through a simplified energy budget. From the energy equation a degree-day method is derived. The rate of snowmelt isfound as a constant multiplied by the temperature excess over an equilibrium temperature which depends on solar radiation.The snowmelt events in Kiruna (3 years) and LuleH (4 years) are analysed utilizing energy balance computations and the degree

In most lakes the wind is the most important flow generating mechanism. In this paper the problem of wind generated circulation - directly wind induced currents and seiches - in small lakes is reviewed. Many field observations are presented and discussed. In the thermocline and the hypolimnion forced seiche currents are shown to dominate the directly induced wind currents. Different kind of non-co

Possible evaporation rates from a snow surface with respect to available energy and vapour pressure deficit in the air are discussed. In literature reported measurements and measurements carried out at the University of Luleå are analysed. It is found that for northern areas the total amount of evaporation during the whole snow covered season amounts only to 10–20 mm.Different formulas for estimat

Hardware implementing spiking neural networks (SNNs) has the potential to provide transformative gains in energy efficiency and throughput for energy-restricted machine-learning tasks. This is enabled by large arrays of memristive synapse devices that can be realized by various emerging memory technologies. But in practice, the performance of such hardware is limited by non-ideal features of the m

A method for including night-time refreezing of the top layer of a snowpack in the degree-day method for computing daily snowmelt rates is presented. It is found that during days of large diurnal temperature variations the daily melt is more determined by the day-time conditions than by the daily mean conditions. Applications are made to an open area and a forested area. The refreezing-degree-day

The snowmelt runoff process from small basins is discussed. A differentiation is made between overland flow in the snowpack and groundwater flow induced by infiltrating meltwater. The effect of variations of the snowmelt intensity on streamflow is studied. It is shown that the runoff is high from the first day of snowmelt runoff if the streamflow is caused by overland flow, and that there are pron