Vaclav Snasel  Pavel Kromer  Jakub Safarik  Jan Platos 《Concurrency and Computation》2020,32(8)

Digital steganography aims at hiding secret messages in digital data transmitted over insecure channels. The JPEG format is prevalent in digital communication, and images are often used as cover objects in digital steganography. Optimization methods can improve the properties of images with embedded secret but introduce additional computational complexity to their processing. AVX instructions available in modern CPUs are, in this work, used to accelerate data parallel operations that are part of image steganography with advanced optimizations.  相似文献   

    

Jaroslava Belkova  Miroslav Rozkot  Petr Danek  Pavel Klein  Jana Matonohova  Iva Podhorna 《Critical reviews in food science and nutrition》2017,57(5):933-936

For many, sugar represents a threat to their health, a perception that is driven by increase in the prevalence of obesity, diabetes, and metabolic disorders, which directly or indirectly is connected with the consumption of sugar. However, is sugar to blame for this health crisis, or are sedentary lifestyle and unhealthy diet equally important? Today, sugars and fats are being targeted for restriction or even prohibition. Should we get rid of sugar altogether and/or does it merit a reprieve? Is the effort to “outlaw” sugars a symptom of nutritional extremism that can be as harmful as any other type of extremism?  相似文献   

    

Melika Sarem  Steffen Lüdeke  Ralf Thomann  Pavel Salavei  Zhaoyong Zou  Wouter Habraken  Admir Masic  V. Prasad Shastri 《Advanced materials (Deerfield Beach, Fla.)》2017,29(35)

The interplay between noncollagenous proteins and biomineralization is widely accepted, yet the contribution of their secondary structure in mineral formation remains to be clarified. This study demonstrates a role for phosvitin, an intrinsically disordered phosphoprotein, in chick embryo skeletal development, and using circular dichroism and matrix least‐squares Henderson–Hasselbalch global fitting, unravels three distinct pH‐dependent secondary structures in phosvitin. By sequestering phosvitin on a biomimetic 3D insoluble cationic framework at defined pHs, access is gained to phosvitin in various conformational states. Induction of biomimetic mineralization at near physiological conditions reveals that a disordered secondary structure with a low content of P_II helix is remarkably efficient at promoting calcium adsorption, and results in the formation of biomimetic hydroxyapatite through an amorphous calcium phosphate precursor. By extending this finding to phosphorylated full‐length human recombinant dentin matrix protein‐1 (17‐513 AA), this bioinspired approach provides compelling evidence for the role of a disordered secondary structure in phosphoproteins in bone‐like apatite formation.  相似文献   

    

Yang Bai  Pavel Tofel  Jaakko Palosaari  Heli Jantunen  Jari Juuti 《Advanced materials (Deerfield Beach, Fla.)》2017,29(29)

An ABO₃‐type perovskite solid‐solution, (K_0.5Na_0.5)NbO₃ (KNN) doped with 2 mol% Ba(Ni_0.5Nb_0.5)O_3?δ (BNNO) is reported. Such a composition yields a much narrower bandgap (≈1.6 eV) compared to the parental composition—pure KNN—and other widely used piezoelectric and pyroelectric materials (e.g., Pb(Zr,Ti)O₃, BaTiO₃). Meanwhile, it exhibits the same large piezoelectric coefficient as that of KNN (≈100 pC N^?1) and a much larger pyroelectric coefficient (≈130 µC m^?2 K^?1) compared to the previously reported narrow‐bandgap material (KNbO₃)_1?x ‐BNNO_x . The unique combination of these excellent ferroelectric and optical properties opens the door to the development of multisource energy harvesting or multifunctional sensing devices for the simultaneous and efficient conversion of solar, thermal, and kinetic energies into electricity in a single material. Individual and comprehensive characterizations of the optical, ferroelectric, piezoelectric, pyroelectric, and photovoltaic properties are investigated with single and coexisting energy sources. No degrading interaction between ferroelectric and photovoltaic behaviors is observed. This composition may fundamentally change the working principles of state‐of‐the‐art hybrid energy harvesters and sensors, and thus significantly increases the unit‐volume energy conversion efficiency and reliability of energy harvesters in ambient environments.  相似文献   

    

Valentin A. Milichko  Sergey V. Makarov  Alexey V. Yulin  Alexandr V. Vinogradov  Andrei A. Krasilin  Elena Ushakova  Vladimir P. Dzyuba  Evamarie Hey‐Hawkins  Evgeny A. Pidko  Pavel A. Belov 《Advanced materials (Deerfield Beach, Fla.)》2017,29(12)

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Vadim Tseilikman  Maria Komelkova  Marina V. Kondashevskaya  Eugenia Manukhina  H. Fred Downey  Valerii Chereshnev  Margarita Chereshneva  Pavel Platkovskii  Anna Goryacheva  Anton Pashkov  Julia Fedotova  Olga Tseilikman  Natalya Maltseva  Olga Cherkasova  Charlotte Steenblock  Stefan R. Bornstein  Barbara Ettrich  George P. Chrousos  Enrico Ullmann 《International journal of molecular sciences》2021,22(24)

Background: Rats exposed to chronic predator scent stress mimic the phenotype of complex post-traumatic stress disorder (PTSD) in humans, including altered adrenal morphology and function. High- and low-anxiety phenotypes have been described in rats exposed to predator scent stress (PSS). This study aimed to determine whether these high- and low-anxiety phenotypes correlate with changes in adrenal histomorphology and corticosteroid production. Methods: Rats were exposed to PSS for ten days. Thirty days later, the rats’ anxiety index (AI) was assessed with an elevated plus-maze test. Based on differences in AI, the rats were segregated into low- (AI ≤ 0.8, n = 9) and high- (AI > 0.8, n = 10) anxiety phenotypes. Plasma corticosterone (CORT) concentrations were measured by ELISA. Adrenal CORT, desoxyCORT, and 11-dehydroCORT were measured by high-performance liquid chromatography. After staining with hematoxylin and eosin, adrenal histomorphometric changes were evaluated by measuring the thickness of the functional zones of the adrenal cortex. Results: Decreased plasma CORT concentrations, as well as decreased adrenal CORT, desoxyCORT and 11-dehydroCORT concentrations, were observed in high- but not in low-anxiety phenotypes. These decreases were associated with increases in AI. PSS led to a significant decrease in the thickness of the zona fasciculata and an increase in the thickness of the zona intermedia. The increase in the thickness of the zona intermedia was more pronounced in low-anxiety than in high-anxiety rats. A decrease in the adrenal capsule thickness was observed only in low-anxiety rats. The nucleus diameter of cells in the zona fasciculata of high-anxiety rats was significantly smaller than that of control or low-anxiety rats. Conclusion: Phenotype-associated changes in adrenal function and histomorphology were observed in a rat model of complex post-traumatic stress disorder.  相似文献   

    

Evgenii Skurikhin  Pavel Madonov  Olga Pershina  Natalia Ermakova  Angelina Pakhomova  Darius Widera  Edgar Pan  Mariia Zhukova  Lubov Sandrikina  Andrey Artamonov  Alexander Dygai 《International journal of molecular sciences》2021,22(11)

Concentration of hyaluronic acid (HA) in the lungs increases in idiopathic pulmonary fibrosis (IPF). HA is involved in the organization of fibrin, fibronectin, and collagen. HA has been proposed to be a biomarker of fibrosis and a potential target for antifibrotic therapy. Hyaluronidase (HD) breaks down HA into fragments, but is a subject of rapid hydrolysis. A conjugate of poloxamer hyaluronidase (pHD) was prepared using protein immobilization with ionizing radiation. In a model of bleomycin-induced pulmonary fibrosis, pHD decreased the level of tissue IL-1β and TGF-β, prevented the infiltration of the lung parenchyma by CD16⁺ cells, and reduced perivascular and peribronchial inflammation. Simultaneously, a decrease in the concentrations of HA, hydroxyproline, collagen 1, total soluble collagen, and the area of connective tissue in the lungs was observed. The effects of pHD were significantly stronger compared to native HD which can be attributed to the higher stability of pHD. Additional spiperone administration increased the anti-inflammatory and antifibrotic effects of pHD and accelerated the regeneration of the damaged lung. The potentiating effects of spiperone can be explained by the disruption of the dopamine-induced mobilization and migration of fibroblast progenitor cells into the lungs and differentiation of lung mesenchymal stem cells (MSC) into cells of stromal lines. Thus, a combination of pHD and spiperone may represent a promising approach for the treatment of IPF and lung regeneration.  相似文献   

    

Evgenii Gerasimov  Alexander Erofeev  Anastasia Borodinova  Anastasia Bolshakova  Pavel Balaban  Ilya Bezprozvanny  Olga L. Vlasova 《International journal of molecular sciences》2021,22(17)

Optogenetics approach is used widely in neurobiology as it allows control of cellular activity with high spatial and temporal resolution. In most studies, optogenetics is used to control neuronal activity. In the present study optogenetics was used to stimulate astrocytes with the aim to modulate neuronal activity. To achieve this goal, light stimulation was applied to astrocytes expressing a version of ChR2 (ionotropic opsin) or Opto-α1AR (metabotropic opsin). Optimal optogenetic stimulation parameters were determined using patch-clamp recordings of hippocampal pyramidal neurons’ spontaneous activity in brain slices as a readout. It was determined that the greatest increase in the number of spontaneous synaptic currents was observed when astrocytes expressing ChR2(H134R) were activated by 5 s of continuous light. For the astrocytes expressing Opto-α1AR, the greatest response was observed in the pulse stimulation mode (T = 1 s, t = 100 ms). It was also observed that activation of the astrocytic Opto-a1AR but not ChR2 results in an increase of the fEPSP slope in hippocampal neurons. Based on these results, we concluded that Opto-a1AR expressed in hippocampal astrocytes provides an opportunity to modulate the long-term synaptic plasticity optogenetically, and may potentially be used to normalize the synaptic transmission and plasticity defects in a variety of neuropathological conditions, including models of Alzheimer’s disease and other neurodegenerative disorders.  相似文献   

    

Svetlana V. Kostyuk  Elena V. Proskurnina  Elizaveta S. Ershova  Larisa V. Kameneva  Elena M. Malinovskaya  Ekaterina A. Savinova  Vasilina A. Sergeeva  Pavel E. Umriukhin  Olga A. Dolgikh  Ekaterina A. Khakina  Olga A. Kraevaya  Pavel A. Troshin  Sergey I. Kutsev  Natalia N. Veiko 《International journal of molecular sciences》2021,22(17)

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Ondrej Chlumsky  Heidi J. Smith  Albert E. Parker  Kristen Brileya  James N. Wilking  Sabina Purkrtova  Hana Michova  Pavel Ulbrich  Jitka Viktorova  Katerina Demnerova 《International journal of molecular sciences》2021,22(21)

In the food industry, the increasing antimicrobial resistance of food-borne pathogens to conventional sanitizers poses the risk of food contamination and a decrease in product quality and safety. Therefore, we explored alternative antimicrobials N-Acetyl-l-cysteine (NAC), rhamnolipids (RLs), and usnic acid (UA) as a novel approach to prevent biofilm formation and reduce existing biofilms formed by important food-borne pathogens (three strains of Salmonella enterica and two strains of Escherichia coli, Listeria monocytogenes, Staphylococcus aureus). Their effectiveness was evaluated by determining minimum inhibitory concentrations needed for inhibition of bacterial growth, biofilm formation, metabolic activity, and biofilm reduction. Transmission electron microscopy and confocal scanning laser microscopy followed by image analysis were used to visualize and quantify the impact of tested substances on both planktonic and biofilm-associated cells. The in vitro cytotoxicity of the substances was determined as a half-maximal inhibitory concentration in five different cell lines. The results indicate relatively low cytotoxic effects of NAC in comparison to RLs and UA. In addition, NAC inhibited bacterial growth for all strains, while RLs showed overall lower inhibition and UA inhibited only the growth of Gram-positive bacteria. Even though tested substances did not remove the biofilms, NAC represents a promising tool in biofilm prevention.  相似文献