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Catechol-O-methyltransferase (COMT) is a key regulator of pain perception, cognitive function, and affective mood. Three common haplotypes of the human COMT gene, divergent in two synonymous and one nonsynonymous position, code for differences in COMT enzymatic activity and are associated with pain sensitivity. Haplotypes divergent in synonymous changes exhibited the largest difference in COMT enzymatic activity, due to a reduced amount of translated protein. The major COMT haplotypes varied with respect to messenger RNA local stem-loop structures, such that the most stable structure was associated with the lowest protein levels and enzymatic activity. Site-directed mutagenesis that eliminated the stable structure restored the amount of translated protein. These data highlight the functional significance of synonymous variations and suggest the importance of haplotypes over single-nucleotide polymorphisms for analysis of genetic variations.

Two-photon excitation of fluorescent proteins is an attractive approach for imaging living systems. Today researchers are eager to know which proteins are the brightest and what the best excitation wavelengths are. Here we review the two-photon absorption properties of a wide variety of fluorescent proteins, including new far-red variants, to produce a comprehensive guide to choosing the right fluorescent protein and excitation wavelength for two-photon applications.

Solution-processed semiconductor quantum dot solar cells offer a path towards both reduced fabrication cost and higher efficiency enabled by novel processes such as hot-electron extraction and carrier multiplication. Here we use a new class of low-cost, low-toxicity CuInSe x S 2− x quantum dots to demonstrate sensitized solar cells with certified efficiencies exceeding 5%. Among other material and device design improvements studied, use of a methanol-based polysulfide electrolyte results in a particularly dramatic enhancement in photocurrent and reduced series resistance. Despite the high vapour pressure of methanol, the solar cells are stable for months under ambient conditions, which is much longer than any previously reported quantum dot sensitized solar cell. This study demonstrates the large potential of CuInSe x S 2− x quantum dots as active materials for the realization of low-cost, robust and efficient photovoltaics as well as a platform for investigating various advanced concepts derived from the unique physics of the nanoscale size regime. Although quantum dots are a promising alternative to dyes in sensitised solar cells, most are based on toxic heavy metals. McDaniel et al. demonstrate devices made with low-cost copper-based quantum dots that achieve certified efficiencies unprecedented for quantum dot sensitized solar cells.

While spatial proteomics by fluorescence imaging has quickly become an essential discovery tool for researchers, fast and scalable methods to classify and embed single-cell protein distributions in such images are lacking. Here, we present the design and analysis of the results from the competition Human Protein Atlas – Single-Cell Classification hosted on the Kaggle platform. This represents a crowd-sourced competition to develop machine learning models trained on limited annotations to label single-cell protein patterns in fluorescent images. The particular challenges of this competition include class imbalance, weak labels and multi-label classification, prompting competitors to apply a wide range of approaches in their solutions. The winning models serve as the first subcellular omics tools that can annotate single-cell locations, extract single-cell features and capture cellular dynamics. A machine learning competition results in tools for labeling protein patterns of single cells in images with population labels. The winners improve the state of the art and provide strategies to deal with weak classification challenges.

The mechanisms of cell proliferation and transformation are intrinsically linked to the process of apoptosis: the default of proliferating cells is to die unless specific survival signals are provided 1 , 2 . Platelet-derived growth factor (PDGF) is a principal survival factor that inhibits apoptosis and promotes proliferation 1 , but the mechanisms mediating its anti-apoptotic properties are not completely understood. Here we show that the transcription factor NF-κB 3 , 4 , 5 is important in PDGF signalling. NF-κB transmits two signals: one is required for the induction of proto-oncogene c-myc and proliferation, and the second, an anti-apoptotic signal, counterbalances c-Myc cytotoxicity. We have traced a putative pathway whereby PDGF activates NF-κB through Ras and phospatidylinositol-3-kinase (PI(3)K) to the PKB/Akt protein kinase and the IκB kinase (IKK); NF-κB thus appears to be a target of the anti-apoptotic Ras/PI(3)K/Akt pathway 6 , 7 . We show that, upon PDGF stimulation, Akt transiently associates in vivo with IKK and induces IKK activation. These findings establish a role for NF-κB in growth factor signalling and define an anti-apoptotic Ras/PI(3)K/Akt/IKK/NF-κB pathway, thus linking anti-apoptotic signalling with transcription machinery.

A schematic thermal diagram of a turbine plant with a thermal gas boiler developed for nuclear power plants with BREST-300 reactors, which considers means for ensuring increasing power generation efficiency at power facilities, is presented. The heat produced in a gas boiler during the combustion of organic fuel is used for an initial and intermediate superheating of the working fluid upstream the turbine cylinders, as well as for preheating the air supplied to the boiler. The BREST-300 NPP discussed in the work is designated as an organic-nuclear power plant (ONPP). In the presented version of the thermal diagram for a turbine plant, the internal efficiency of the cycle is 54.12%.

One process limiting the performance of solar cells is rapid cooling (thermalization) of hot carriers generated by higher-energy solar photons. In principle, the thermalization losses can be reduced by converting the kinetic energy of energetic carriers into additional electron-hole pairs via carrier multiplication (CM). While being inefficient in bulk semiconductors this process is enhanced in quantum dots, although not sufficiently high to considerably boost the power output of practical devices. Here we demonstrate that thick-shell PbSe/CdSe nanostructures can show almost a fourfold increase in the CM yield over conventional PbSe quantum dots, accompanied by a considerable reduction of the CM threshold. These structures enhance a valence-band CM channel due to effective capture of energetic holes into long-lived shell-localized states. The attainment of the regime of slowed cooling responsible for CM enhancement is indicated by the development of shell-related emission in the visible observed simultaneously with infrared emission from the core. Carrier multiplication can improve the performance of solar cells, but its efficiency is still not high enough to considerably increase the power output of practical devices. Cirloganu et al. show that appropriately designed core-shell quantum dots can enhance the carrier multiplication yield four-fold.

Morphofunctional properties of spindle-shaped platelets under normal and pathological conditions were studied by the method based on vital staining. In donor blood and plasma isolated by centrifugation at 300 g , no spindle-shaped platelets were detected; after centrifugation at 3000 g , spindle-shaped platelets were detected in a small amount in 20% samples. During plasma storage at 20-22°C, spindle-shaped platelets appeared after 1-2 days, after 3 days their number increased to 30% and higher. Spindle-shaped platelets contained a small number of granules and did not exhibit active adhesion, while the structure of their membranes was normal after 1-2 days of storage and abnormalities appeared during subsequent storage. Spindle-shaped platelets were found in the blood of patients with acute exogenous poisoning and severe thermal trauma. Spindle-shaped platelets can be used as an additional criterion for assessing the quality of the platelet population.

The studies were conducted in 2011–2022 to improve the methods of in vitro treatment of garden crops from harmful viruses by increasing the efficiency of treatment and environmental safety. Salicylic acid at a concentration of 3 × 10 –4 M was used as an antiviral drug in the nutrient medium. Microcuttings at the stage of micropropagation itself for the purpose of treatment from viruses and increasing the reproduction rate, as well as at the rooting stage to increase rooting and improve root development, were treated using the SMI-5 model device for magnetic pulse treatment with magnetic induction pulses with a changing increasing frequency from 0.8 to 51.2 Hz for 10 min with a step of 0.2 Hz. When improving the clonal rootstocks of apple and pear trees, the use of salicylic acid made it possible to increase the yield of explants of apple rootstocks free from latent viruses by 11.8–23.7% and of pear rootstocks by 38.4–40% depending on the type of virus. A low index of latent virus content is observed during complex therapy of apple rootstock explants using salicylic acid and thermo- and magnetic therapy. Magnetic treatment contributed to the improvement of the vegetative development of explants at the propagation stage: the number of shoots increased by 1.6–1.7 times depending on the culture. At the rooting stage, in microshoots of the studied crops treated with magnetic induction pulses, significant stimulation of rhizogenesis and an increase in the number and length of roots were observed. When planting microplants in nonsterile conditions, magnetic treatment led to an improvement in their survival rate by 8–13% depending on the crop. The advantages of magnetic processing include the absence of phytotoxicity, versatility, higher yield of healthy plants, automation, and environmental safety of the processing process.

Turbulence is ubiquitous in the universe and in fluid dynamics. It influences a wide range of high energy density systems, from inertial confinement fusion to astrophysical-object evolution. Understanding this phenomenon is crucial, however, due to limitations in experimental and numerical methods in plasma systems, a complete description of the turbulent spectrum is still lacking. Here, we present the measurement of a turbulent spectrum down to micron scale in a laser-plasma experiment. We use an experimental platform, which couples a high power optical laser, an x-ray free-electron laser and a lithium fluoride crystal, to study the dynamics of a plasma flow with micrometric resolution (~1μm) over a large field of view (>1 mm 2 ). After the evolution of a Rayleigh–Taylor unstable system, we obtain spectra, which are overall consistent with existing turbulent theory, but present unexpected features. This work paves the way towards a better understanding of numerous systems, as it allows the direct comparison of experimental results, theory and numerical simulations. Turbulence effects explored use macroscale systems in general. Here the authors generate a turbulent plasma using laser irradiation of a solid target and study the dynamics of the plasma flow at the micron-scale by using scattering of an XFEL beam.