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Bulk samples of pure polyvinyl chloride (PVC) and its composites with different content of methylene blue (MB) dye are prepared. The degree of crystallinity, dynamic elastic modulus E and shear modulus G (~1 MHz), photoluminescence (PL), temperature dependences of dielectric characteristics ε1, ε2, tgδ, electrical resistance R at different frequencies of alternating electric field are measured. As shown, the adding of a modifier (MB) with conjugated chromophores is accompanied by both the generation of linear conjugated systems (polyenes) in PVC and the destruction of monomer units. These processes are mechanisms for changing the mechanical, structural, optical, dielectric properties of PVC–MB composites caused by the peculiarities of the stack interaction between their conjugated components. [ABSTRACT FROM AUTHOR]

A method for the experimental determination of turbidity in thermoresponsive polymer solutions is presented. The method is based on measuring the intensity of light streams: weakened and backscattered from the sample, which is in the region of the volume phase transition. The turbidimeter developed by us, unlike industrial devices of this type, is equipped with a thermostat that allows to study the dependence of the solution turbidity on the temperature. The device operates automatically, the values of luminosity and temperature from digital sensors are processed by the microcontroller and transmitted via the RS-232 protocol to USB ports of a personal computer. The error of luminosity measurement does not exceed 0.1 lux, the temperature measurement accuracy is ± 0.1 °C. This article demonstrates an example of using the designed turbidimeter to study the first-order phase transition in an aqueous solution of hydroxypropylcellulose (2 wt. %) in the presence (absence) of NaCl ions. It is assumed that the sol-gel transition in the investigated solution is due to swelling of polymer coils and their subsequent aggregation. In our opinion, the displacement of the phase transition temperature is due to additional swelling of polymer coils owing to shielding of the electrostatic interaction of monomers in the presence of NaCl ions. It is shown that the intensity of backscattered light corresponds to the kinetics of the formation of the gel network, which makes it possible to establish the dimensions of formed aggregates in the network nodes. [ABSTRACT FROM AUTHOR]

Ukraine is an agricultural country with great agricultural potential for biogas production, which is the key to fertile soils and favorable climatic conditions for energy crops, including corn. The article analyzes the experience of using biogas in Ukraine and the world, its mechanism of production. The leader in biogas production in the world is the European Union in general and Germany in particular. The total number of biogas plants in Europe exceeds 11 thousand, of which 7.2 thousand in Germany. Installed biogas, which is released in the process of complex fermentation of organic waste, consists of a mixture of gases: methane - 55-75%, carbon dioxide - 23-33%, hydrogen sulfide - 7%. An important sector of renewable energy sources in biogas production is presented and the prospects for its use are determined. The energy dependence of our country on the volumes of imported natural gas is analyzed. The main aspects of biogas production are explored using renewable energy sources that are inexhaustible in our crane and the phased operation of the biogas plant is investigated. The real advantages of the need for biogas production and use in our country are outlined. Problems aimed at the development of alternative energy have been proved in order to detect environmental pollution. It has been established that in Ukraine the use of corn silage to improve the efficiency of biogas production at existing biogas stations has not been used so far. The problems of increasing the yield of corn plants have been proved not only by breeding and genetic methods, but also by cultivation technology. [ABSTRACT FROM AUTHOR]

Composite samples based on microcrystalline cellulose matrix incorporated with micro/nanoparticles of La0.7Sm0.3VO4 complex oxide were made by cool pressing procedure. Morphology, crystallinity and characteristic luminescence and dielectric properties of the composites were studied. Their morphology can be described as "ceramics-like" type, as it consists of cellulose plates and embedded oxide particles. Luminescence spectra of the composites covers the range of the whole visible light, 350-750 nm, and comprises both wide band and narrow lines, related with host and oxide luminescence, respectively. Temperature dependences of the dielectric permittivity of composites showed the impact of the oxide particles on the characteristics of the microcrystalline cellulose. An assumption was made that this influence can be affected via water molecules, hydroxyl groups or molecules of the ambient gases. Studied composites can be perspective luminescent materials for transformation of ultraviolet and violet radiation into green-red light. [ABSTRACT FROM AUTHOR]

We select the organic acid for pre-decarbonization of the Ukrainian low-grade phosphate raw material. Through experiments conducted, we determine that lactic acid is the most effective in this process. We also demonstrate the infrared spectra of the original phosphate (Ratnovskiy field), as well as of the phosphate treated with chlorine and lactic acid. They indicate that the intensity of stretch vibration, belonging to the carbonate ion of calcite, decreases after treatment with lactic acid phosphate. [ABSTRACT FROM AUTHOR]

Abstract Background NASP (Nuclear Autoantigenic Sperm Protein) is a histone chaperone that is present in all dividing cells. NASP has two splice variants: tNASP and sNASP. Only cancer, germ, transformed, and embryonic cells have a high level of expression of the tNASP splice variant. We examined the consequences of tNASP depletion for prostate cancer PC-3 cells. Methods tNASP was depleted from prostate cancer PC-3 cells, cervical cancer HeLa cells, and prostate epithelial PWR-1E cells using lentivirus expression of tNASP shRNA. Cell cycle changes were studied by proliferation assay with CFSE labeling and double thymidine synchronization. Gene expression profiles were detected using RT2Profiler PCR Array, Western and Northern blotting. Results PC-3 and HeLa cells showed inhibited proliferation, increased levels of cyclin-dependant kinase inhibitor p21 protein and apoptosis, whereas non-tumorigenic PWR-1E cells did not. All three cell types showed decreased levels of HSPA2. Supporting in vitro experiments demonstrated that tNASP, but not sNASP is required for activation of HSPA2. Conclusions Our results demonstrate that PC-3 and HeLa cancer cells require tNASP to maintain high levels of HSPA2 activity and therefore viability, while PWR-1E cells are unaffected by tNASP depletion. These different cellular responses most likely arise from changes in the interaction between tNASP and HSPA2 and disturbed tNASP chaperoning of linker histones. This study has demonstrated that tNASP is critical for the survival of prostate cancer cells and suggests that targeting tNASP expression can lead to a new approach for prostate cancer treatment.

Abstract Background NASP (Nuclear Autoantigenic Sperm Protein) is a linker histone chaperone required for normal cell division. Changes in NASP expression significantly affect cell growth and development; loss of gene function results in embryonic lethality. However, the mechanism by which NASP exerts its effects in the cell cycle is not understood. To understand the pathways and networks that may involve NASP function, we evaluated gene expression in HeLa cells in which NASP was either overexpressed or depleted by siRNA. Methods Total RNA from HeLa cells overexpressing NASP or depleted of NASP by siRNA treatment was converted to cRNA with incorporation of Cy5-CTP (experimental samples), or Cy3-CTP (control samples). The labeled cRNA samples were hybridized to whole human genome microarrays (Agilent Technologies, Wilmington, Delaware, USA). Various gene expression analysis techniques were employed: Significance Analysis of Microarrays (SAM), Expression Analysis Systematic Explorer (EASE), and Ingenuity Pathways Analysis (IPA). Results From approximately 36 thousand genes present in a total human genome microarray, we identified a set of 47 up-regulated and 7 down-regulated genes as a result of NASP overexpression. Similarly we identified a set of 56 up-regulated and 71 down-regulated genes as a result of NASP siRNA treatment. Gene ontology, molecular network and canonical pathway analysis of NASP overexpression demonstrated that the most significant changes were in proteins participating in organismal injury, immune response, and cellular growth and cancer pathways (major "hubs": TNF, FOS, EGR1, NFκB, IRF7, STAT1, IL6). Depletion of NASP elicited the changed expression of proteins involved in DNA replication, repair and development, followed by reproductive system disease, and cancer and cell cycle pathways (major "hubs": E2F8, TP53, FGF, FSH, FST, hCG, NFκB, TRAF6). Conclusion This study has demonstrated that NASP belongs to a network of genes and gene functions that are critical for cell survival. We have confirmed the previously reported interactions between NASP and HSP90, HSP70, histone H1, histone H3, and TRAF6. Overexpression and depletion of NASP identified overlapping networks that included TNF as a core protein, confirming that both high and low levels of NASP are detrimental to cell cycle progression. Networks with cancer-related functions had the highest significance, however reproductive networks containing follistatin and FSH were also significantly affected, which confirmed NASP's important role in reproductive tissues. This study revealed that, despite some overlap, each response was associated with a unique gene signature and placed NASP in important cell regulatory networks.

The first steps in vision take place in photoreceptor cells, which are highly compartmentalized neurons exhibiting significant structural variation across species. The light-sensitive ciliary compartment, called the outer segment, is located atop of the cell soma, called the inner segment. In this study, we present an ultrastructural analysis of human photoreceptors, which reveals that, in contrast to this classic arrangement, the inner segment of human rods extends alongside the outer segment to form a structure hereby termed the "accessory inner segment". While reminiscent of the actin-based microvilli known as "calyceal processes" observed in other species, the accessory inner segment is a unique structure: (1) it contains an extensive microtubule-based cytoskeleton, (2) it extends far alongside the outer segment, (3) its diameter is comparable to that of the outer segment, (4) it contains numerous mitochondria, and (5) it forms electron-dense structures that likely mediate adhesion to the outer segment. Given that the spacing of extrafoveal human photoreceptors is more sparse than in non-primate species, with vast amounts of interphotoreceptor matrix present between cells, the closely apposed accessory inner segment likely provides structural support to the outer segment. This discovery expands our understanding of the human retina and directs future studies of human photoreceptor function in health and disease.

Drilling of Carbon Fiber-Reinforced Plastic/Titanium alloy (CFRP/Ti) stacks represents one of the most widely used machining methods for making holes to fasten assemblies in civil aircraft. However, poor machinability of CFRP/Ti stacks in combination with the inhomogeneous behavior of CFRP and Ti alloy face manufacturing and scientific community with a problem of defining significant factors and conditions for ensuring hole quality in the CFRP/Ti alloy stacks. Herein, we investigate the effects of drilling parameters on drilling temperature and hole quality in CFRP/Ti alloy stacks by applying an artificial neuron network (ANN). We varied cutting speed, feed rate, and time delay factors according to the factorial design L 9 Taguchi orthogonal array and measured the drilling temperature, hole diameter, and out of roundness by using a thermocouple and coordinate measuring machine methods for ANN analysis. The results show that the drilling temperature was sensitive to the effect of stack material layer, cutting speed, and time delay factors. The hole diameter was mainly affected by feed, stack material layer, and time delay, while out of roundness was influenced by the time delay, stack material layer, and cutting speed. Overall, ANN can be used for the identification of the drilling parameters-hole quality relationship.

Background: Pemigatinib is an inhibitor of the fibroblast growth factor receptor (FGFR), recently approved for the treatment of cholangiocarcinoma. FGFR retinopathy is a newly recognized entity, with only two other FGFR inhibitors reported to cause serous retinopathy. Herein, we describe the first published report of a multifocal serous retinopathy secondary to pemigatinib., Case Presentation: A 67-year-old male with stage 4A metastatic colon adenocarcinoma undergoing systemic therapy with pemigatinib was found to have developed bilateral multifocal serous retinopathy. Fundus autofluorescence showed corresponding multifocal hypoautofluorescent foci, whereas fluorescein angiography and indocyanine green angiography were unremarkable. Subretinal fluid resolved rapidly after discontinuation of pemigatinib., Conclusions: Multifocal serous retinopathy appears to be a class effect of FGFR inhibitors. FGFR retinopathy clinically resembles MEK retinopathy-both feature multifocal subretinal fluid, low visual significance, and quick resolution. However, given that FGFR inhibitors have a broader molecular range than MEK inhibitors, further characterization of FGFR retinopathy is necessary to generate management guidelines.

Purpose: Herpes simplex virus type I (HSV-1) infection of corneal epithelial cells activates ataxia telangiectasia mutated (ATM), an apical kinase in the host DNA damage response pathway, whose activity is necessary for the progression of lytic HSV-1 infection. The purpose of this study is to investigate the mechanism of ATM activation by HSV-1 in the corneal epithelium, as well as its functional significance., Methods: Mechanistic studies were performed in cultured human corneal epithelial cell lines (hTCEpi, HCE), as well as in esophageal (EPC2) and oral (OKF6) cell lines. Transfection-based experiments were performed in HEK293 cells. HSV-1 infection was carried out using the wild-type KOS strain, various mutant strains (tsB7, d120, 7134, i13, n208), and bacterial artificial chromosomes (fHSVΔpac, pM24). Inhibitors of ATM (KU-55933), protein synthesis (cycloheximide), and viral DNA replication (phosphonoacetic acid) were used. Outcomes of infection were assayed using Western blotting, qRT-PCR, immunofluorescence, and comet assay., Results: This study demonstrates that HSV-1-mediated ATM activation in corneal epithelial cells relies on the viral immediate early gene product ICP4 and requires the presence of the viral genome in the host nucleus. We show that ATM activation is independent of viral genome replication, the ICP0 protein, and the presence of DNA lesions. Interestingly, ATM activity appears to be necessary at the onset of infection, but dispensable at the later stages., Conclusions: This study expands our understanding of HSV-1 virus-host interactions in the corneal epithelium and identifies potential areas of future investigation and therapeutic intervention in herpes keratitis.

The set of composite materials that consist of micro/nanocellulose and complex K 2 Eu(MoO 4 )(PO 4 ) luminescent oxide particles was prepared. The composites were studied by means of scanning electron microscopy, XRD analysis, dilatometry, differential scanning calorimetry and thermogravimetric analysis, and dielectric and luminescence spectroscopy.Dependencies of density, crystallinity, relative extension, thermal extension coefficient, dielectric relaxation parameters, intensity and shape of photoluminescence bands on temperature, and content of oxide component were studied. The structure of the composite without oxide is formed by grains of nearly 5-50 μm in size (crystallinity is about ~56%). Structure of the micro/nanocellulose samples which contain oxide particles is similar, but the cellulose grains are deformed by oxide particles. Dependencies of the abovementioned properties on temperature and oxide content were analyzed together with data on the size distribution of oxide particles for the samples for various oxide and molecules of water concentrations.

Purpose: Herpes keratitis (HK) is the leading cause of cornea-derived and infection-associated blindness in the developed world. Despite the availability of effective antivirals, some patients develop refractory disease, drug-resistant infection, and topical toxicity. A nonpharmaceutical treatment modality may offer a unique advantage in the management of such cases. This study investigated the antiviral effect of nonthermal dielectric barrier discharge (DBD) plasma, a partially ionized gas that can be applied to organic substances to produce various biological effects., Methods: Human corneal epithelial cells and explanted corneas were infected with herpes simplex virus type 1 (HSV-1) and exposed to culture medium treated with nonthermal DBD plasma. The extent of infection was measured by plaque assay, quantitative PCR, and Western blot. Corneal toxicity assessment was performed with fluorescein staining, histologic examination, and 8-OHdG detection., Results: Application of DBD plasma-treated medium to human corneal epithelial cells and explanted corneas produced a dose-dependent reduction of the cytopathic effect, viral genome replication, and the overall production of infectious viral progeny. Toxicity studies showed lack of detrimental effects in explanted human corneas., Conclusions: Nonthermal DBD plasma substantially suppresses corneal HSV-1 infection in vitro and ex vivo without causing pronounced toxicity., Translational Relevance: Nonthermal plasma is a versatile tool that holds great biomedical potential for ophthalmology, where it is being investigated for wound healing and sterilization and is already in use for ocular microsurgery. The anti-HSV-1 activity of DBD plasma demonstrated here could be directly translated to the clinic for use against drug-resistant herpes keratitis.