Histone N‐terminal tails of nucleosomes are the sites of complex regulation of gene expression through post‐translational modifications. Among these modifications, histone methylation had long been ...associated with permanent gene inactivation until the discovery of Lys‐specific demethylase (LSD1), which is responsible for dynamic gene regulation. There are more than 30 members of the Lys demethylase (KDM) family, and with exception of LSD1 and LSD2, all other KDMs possess the Jumonji C (JmjC) domain exhibiting demethylase activity and require unique cofactors, for example, Fe(II) and α‐ketoglutarate. These cofactors have been targeted when devising KDM inhibitors, which may yield therapeutic benefit. KDMs and their counterpart Lys methyltransferases (KMTs) regulate multiple biological processes, including oncogenesis and inflammation. KDMs’ functional interactions with retinoblastoma (Rb) and E2 factor (E2F) target promoters illustrate their regulatory role in cell cycle progression and oncogenesis. Recent findings also demonstrate the control of inflammation and immune functions by KDMs, such as KDM6B that regulates the pro‐inflammatory gene expression and CD4+ T helper (Th) cell lineage determination. This review will highlight the mechanisms by which KDMs and KMTs regulate the target gene expression and how epigenetic mechanisms may be applied to our understanding of oral inflammation.
Abstract
The present study is concerned with the prediction of deformation in incremental sheet forming (ISF) for a Ti6Al4V sheet. To investigate anisotropic and asymmetric behaviors, uniaxial ...tension and compression tests were conducted along the rolling direction (RD), diagonal direction (DD), and transverse direction (TD). A representative yield function for a HCP material, the Cazacu–Plunkett–Barlat (CPB06) yield criterion, was selected for constitutive modeling to take into account anisotropy/asymmetry-induced distortional yielding of the titanium alloy. The chord modulus degradation was confirmed through uniaxial loading–unloading tests. The ISF tests were carried out using a single contact-point tool following a truncated pyramid tool path. To predict the deformation during the ISF, finite element analyses were conducted with the ABAQUS explicit and the vectorized user-subroutine (VUMAT). The performance of various constitutive models was evaluated based on the comparison of deformed shapes and distribution of thickness from the experiment and the FEA.
The role of electrical potential, charge transport, and recombination in determining the photopotential and photocurrent conversion efficiency (IPCE) of dye-sensitized nanocrystalline solar cells was ...studied. Electrostatic arguments and electrical impedance spectroscopy (EIS) are used to obtain information on the electrical and electrochemical potential distribution in the cell. It is shown that on the macroscopic level, no significant electrical potential drop exists within the porous TiO2 when it contacts the electrolyte and that the electrical potential drop at the transparent conducting oxide substrate (TCO)/TiO2 interface occurs over a narrow region, one or two layers of TiO2. Analyses of EIS and other data indicate that both the photopotential of the cell and the decrease of the electrical potential drop across the TCO/TiO2 interface are caused by the buildup of photoinjected electrons in the TiO2 film. The time constants for the recombination and collection of the photoinjected electrons are measured by EIS and intensity-modulated photocurrent spectroscopy (IMPS). As the applied bias is varied from short-circuit to open-circuit conditions at 1 sun light intensity, recombination becomes faster, the collection of electrons becomes slower, and the IPCE decreases. The decrease of IPCE correlates directly with the decline of the charge-collection efficiency ηcc, which is obtained from the time constants for the recombination and collection of the photoinjected electrons. Significantly, at open circuit, η cc is only 45% of its short-circuit value, indicating that the dye-sensitized nanocrystalline TiO2 solar cell behaves as a nonideal photodiode.
In this investigation, the effect of austenitization temperature on microstructural evolution, mechanical properties, fracture mode, and wear mechanism of a high carbon Hadfield steel was studied. ...Four blocks of the Hadfield steel were cast in an induction furnace. One hour austenitization was performed at 1000 °C, 1075 °C, 1150 °C, and 1225 °C on the cast samples followed by quenching in water. Uniaxial tensile test, pin on disk wear test and Vickers hardness measurements were employed on the processed samples. An optical microscope and a field emission scanning electron microscope were used to study the microstructural evolution. Transmission electron microscope was employed to observe the carbides that were formed. Moreover, scanning electron microscopy technique was used to define the mode of fracture on the tensile test samples. Results showed that increasing austenitization temperature reduced carbides and increased austenite grain size. Mechanical properties measurements also showed that increasing austenitization temperature increased yield/tensile strengths, hardness, and wear resistance of this steel. However, these increments were made at the expense of ductility. Fractography results showed a very ductile mode of fracture. The share of the ductile fracture mode was further increased by reducing the austenitization temperature from 1225 °C to 1000 °C.
•Delamination and discoloration were investigated with 25-year-old module.•Delamination and discoloration result in the drop of short circuit current (Isc).•Corrosion occurred at the interconnection ...between cell metallization-Cu interconnection.•Delamination occurs at the interface cell and encapsulant.
Discoloration and delamination (D&D) of encapsulant in a photovoltaic (PV) module affect the electrical characteristics. Therefore, in this study D&D-induced degradations are investigated with a 25-year-old PV module. The average power output of 25-year-old PV modules decreased by 17.9% compared to initial value. However, insulation properties have been stable over 25years. Electroluminescence image shows that discoloration has an effect on the cell degradation. The effect of D&D on the light reflectance and transmittance is evaluated by performing a trapezoidal integration with the standard global reference spectrum. Failure analysis reveals that delamination occurs at the interface between encapsulant and solar cell and also shows that corrosion of solder occurred near delamination site
Gamma titanium aluminide intermetallic alloys are lightweight heat-resistant materials and their thermo-mechanical properties are affected by hot working. The aim of this study was initially to ...evaluate the texture developed in a cast Ti-48Al-2Cr alloy during thermo-mechanical treatment at 1000 ℃ at different strain rates of 0.001, 0.01 and 0.1s−1. In addition, development of ultrafine grained microstructure was assessed for different strain rates. The results of pole figures suggested that the amount of the strain rate is one of the most crucial parameter affecting the type of texture developed. So that, when the rate of strain increased from 0.001 to 0.1s−1 the texture changed from Copper to Brass. The results also showed that by increasing the strain rate yield strength, hardness increased substantially. Microstructural study showed that by increasing strain rates, the mean size of the grains reduced even down to nano-range (i.e. <100nm). A high-volume fraction of dynamic recrystallization occurred when strain rate was more than 0.01s−1. Abnormal grain growth is also observed when the samples are hot strained by low strain rates.
This paper presents a multiobjective genetic algorithm approach to the design of a water distribution network. The objectives considered are minimization of the network cost and maximization of a ...reliability measure. In this study, a new reliability measure, called network resilience, is introduced. This measure mimics a designer's desire of providing excess head above the minimum allowable head at the nodes and of designing reliable loops with practicable pipe diameters. The proposed method produces a set of Pareto-optimal solutions in the search space of cost and network resilience. Genetic algorithms are observed to be poor in handling constraints. To handle constraints in a better way, a constraint handling technique that does not require a penalty coefficient and is applicable to water distribution systems is presented. The present model is applied to two example problems, which are widely reported. Comparison of the present method with other methods revealed that the network resilience based approach gave better results.
Celotno besedilo
Dostopno za:
DOBA, FGGLJ, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Objectives: The objectives of this study were to (1) develop an empirical typology of social networks in older Koreans; and (2) examine its effect on physical and mental health.
Method: A sample of ...6900 community-dwelling older adults in South Korea was drawn from the 2014 Korean National Elderly Survey. Latent profile analysis (LPA) was conducted to derive social network types using eight common social network characteristics (marital status, living arrangement, the number and frequency of contact with close family/relatives, the number and frequency of contact with close friends, frequency of participation in social activities, and frequency of having visitors at home). The identified typologies were then regressed on self-rated health and depressive symptoms to explore the health risks posed by the group membership.
Results: The LPA identified a model with five types of social network as being most optimal (BIC = 153,848.34, entropy = .90). The groups were named diverse/family (enriched networks with more engagement with family), diverse/friend (enriched networks with more engagement with friends), friend-focused (high engagement with friends), distant (structurally disengaged), and restricted (structurally engaged but disengaged in family/friends networks). A series of regression analyses showed that membership in the restricted type was associated with more health and mental health risks than all types of social networks except the distant type.
Conclusion: Findings demonstrate the importance of family and friends as a source of social network and call attention to not only structural but also non-structural aspects of social isolation. Findings and implications are discussed in cultural contexts.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
We present a study of γ-ray emission from the core-collapse supernova remnant Cas A in the energy range from 0.1 GeV to 10 TeV. We used 65 hr of the Very Energetic Radiation Imaging Telescope Array ...System (VERITAS) data to cover 200 GeV-10 TeV, and 10.8 yr of Fermi-Large Area Telescope (LAT) data to cover 0.1-500 GeV. The spectral analysis of Fermi-LAT data shows a significant spectral curvature around 1.3 0.4stat GeV that is consistent with the expected spectrum from pion decay. Above this energy, the joint spectrum from Fermi-LAT and VERITAS deviates significantly from a simple power law, and it is best described by a power law with a spectral index of 2.17 0.02stat and a cutoff energy of 2.3 0.5stat TeV. These results, along with radio, X-ray, and γ-ray data, are interpreted in the context of leptonic and hadronic models. Assuming a one-zone model, we exclude a purely leptonic scenario and conclude that proton acceleration up to at least 6 TeV is required to explain the observed γ-ray spectrum. From modeling of the entire multiwavelength spectrum, a minimum magnetic field inside the remnant of Bmin 150 G is deduced.
PDF
