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Anticancer treatment is performed in various ways, and photothermal therapy (PTT) is gaining traction from a noninvasive treatment perspective. PTT is a treatment technique based on the photothermal effect that kills tumors by increasing their temperature. In this study, gold nanoparticles (AuNPs), which are photothermal agents, were used in numerical simulations to determine the PTT effect by considering diffusion induced changes in the distribution area of the AuNPs. The treatment effect was confirmed by varying the initial injection radius of AuNPs represented by the injection volume, the elapsed time after injection of AuNPs, and the laser intensity. The degree of maintenance of the apoptotic temperature band in the tumor was quantitatively analyzed by the apoptotic variable. Ultimately, if the initial injection radius of AuNPs is 0.7 mm or less, the optimal time to start treatment is 240 min after injection, and for 1.0 and 1.2 mm, it is optimal to start treatment when the elapsed time after injection is 90 and 30 min, respectively. This study identified the optimal treatment conditions for dosage of AuNPs and treatment start time in PTT using AuNPs, which will serve as a reference point for future PTT studies. [ABSTRACT FROM AUTHOR]

The effects of varying γ′ size and grain boundary carbide distribution at elevated temperatures on the fatigue behavior of turbine disk alloy RR1000 were examined through combining 2D and 3D imaging characterization. The fatigue crack growth rate at 725°C is higher than at 650°C due to enhanced oxidation damage at higher temperature, dominated by an intergranular fracture mode. This is more marked with longer dwell time (linked to diffusion time) and when carbides have formed continuously at grain boundaries. The fatigue crack path was characterized by X‐ray CT scan to present the complex 3D crack propagation morphology. It is noted that a discontinuous crack path and uncracked ligaments can be discerned ahead of the crack tip particularly in the microstructure where carbides are continuously formed at grain boundaries. This is linked to embrittled zones ahead of the crack tip formed during longer dwell times at the maximum stress during cycling at elevated temperature. Highlights: Effects of microstructure and temperature on fatigue crack growth of Ni‐based superalloy.Deeper understanding of high‐temperature fatigue mechanism by 2D/3D image characterization.X‐ray CT scan revealing complex 3D crack morphology linked to oxidation fatigue mechanism. [ABSTRACT FROM AUTHOR]

The tropical climate variabilities, such as Indian Ocean Dipole (IOD) and El Niño Southern Oscillation (ENSO), are accompanied by changes in the tropical deep convection which can influence the atmospheric circulation in the Southern Hemisphere (SH). To investigate each role of IOD and ENSO in the September‐November (SON) circulation, we examine teleconnection patterns associated with IOD and ENSO events using the ERA5 monthly averaged data from 1979 to 2020. Our approach is to calculate the power spectral density (PSD) of the sea level pressure (SLP) and meridional wind and geopotential height at 300 hPa that are decomposed by zonal wave numbers (ZWNs), and to compute their correlations with IOD and ENSO at each latitudinal band. The main results are that IOD (ENSO) is negatively (positively) correlated with PSDs of ZWN2 and ZWN3 (ZWN1) at 300 hPa in the SH middle latitudes. Considering the Rossby wave train, IOD (ENSO) considerably affects the variability of the ZWN3 (ZWN1) pattern, which influences the meridional exchange of momentum. Additionally, the relationship between IOD and ZWN3 has become tighter in recent years, which is not seen in that with ENSO. The IOD and ENSO events also modify the SLP patterns and meridional surface winds, modulating the sea ice extent in the Southern Ocean. During the highly positive 2019 IOD event, the variability of the middle latitudes atmospheric circulation was considerably larger than climatology, suggesting a higher chance of more extreme weather patterns associated with more frequent intense IOD events in the warming climate. Plain Language Summary: The two tropical climate variabilities, Indian Ocean Dipole (IOD) and El Niño Southern Oscillation (ENSO), can change the location and intensity of tropical convection, generate anomalous Rossby wave trains heading to the Southern Hemisphere (SH), and the zonal wave pattern of the middle latitudes' atmospheric circulation and further the Antarctic climate. We analyzed this low‐high latitudes teleconnection in the austral spring when IOD and ENSO strongly affect the wave patterns using atmospheric reanalysis data. The results show that ENSO is positively correlated with zonal wave number 1 (ZWN1) activity, but IOD negatively correlates with ZWN2 and ZWN3 activities in the SH middle latitudes. The relationship between IOD and ZWN3 has become tighter in recent years, which is not seen in that with ENSO. The IOD and ENSO events also modify the sea level pressure patterns and meridional surface winds in the Southern Ocean, leaving the ZWN3 features. The surface wind patterns affect the sea ice concentration, but with a difference between IOD and ENSO. Key Points: Indian Ocean Dipole (IOD)'s Rossby wave train is partially similar to the climatology; a negative IOD enormously increases zonal wavenumber 3IOD (El Niño Southern Oscillation) is negatively (positively) correlated with zonal wavenumber 2 and 3 (1) in austral springThe extremely positive IOD in 2019 exhibited more significant increases and unusual changes in wave patterns [ABSTRACT FROM AUTHOR]

Rectangular coaxial slot arrays (RCSAs) are antennas designed to ensure superior field penetration depth with a high signal‐to‐noise ratio (S/N) in the deeper imaging region of ultra‐high magnetic resonance imaging (MRI). The RCSA consists of a transmission line of λ/4 length surrounded by a dielectric material, and a ground plate that resembles a rectangular coaxial line. We extended this antenna to eight elements. The simulation indicates that a single RCSA has a B1+‐field distribution similar to that of the generally used dipole antenna for traveling RF waves. However, the B1+‐component of the RCSA in an array configuration was stronger in the deep brain region of the human brain model and its specific absorption rate was lower compared to the dipole and monopole antenna arrays. The proposed RSCA array can be adapted to acquire MR signals with high sensitivity in a deeper imaging region in an ultra‐high field MRI scanner. [ABSTRACT FROM AUTHOR]

Birdcage (BC) coils generate a homogeneous magnetic field (∣B1∣), whose strength depends on the length of the coils, the number of legs, the resonance frequency, the excitation method, and the length‐to‐diameter ratio. BC coils with a shorter distance between the end rings produce a more intense ∣B1∣ field with a higher level of homogeneity. Here, we propose a combination of overlapping and nonoverlapping radiofrequency volumetric BC coils for small‐animal magnetic resonance imaging (MRI) working at 7 T with a frequency of 300 MHz to improve the ∣B1∣‐field homogeneity and intensity along the main magnetic field (∣B0∣) direction. The first combination consisted of two overlapping BC (o‐BC) coils, in which each coil is half the length of the imaging object. A combination of two nonoverlapping BC coils separated by a small gap (nog‐BC) was also developed. In order to improve the performance of the nog‐BC coil, we attached a decoupling capacitor. In computational calculations, the proposed o‐BC coil configuration showed an increased homogeneity in the ∣B1∣ field along the ∣B0∣ direction compared with the other coils. The experimental bench tests of the o‐BC coil configuration showed a high decoupling coefficient between the BC coils, which allowed each of them to be used individually for transmission and reception. The o‐BC coil was able to maintain a high transmission efficiency without signal interference while exhibiting an increased ∣B1∣‐field homogeneity compared with other coils. In this study, the advantages of the o‐BC coils are demonstrated using electromagnetic simulations and MRI on a homogenous phantom and an in vivo mouse body. [ABSTRACT FROM AUTHOR]

BACKGROUND: Equol is a major isoflavone metabolite, and equol‐producing bacteria have been isolated and characterized; however, fermentation has been performed with soybean‐based products as substrates. Pueraria lobata has been reported as a plant with higher content of isoflavones. RESULTS: The genome of new equol‐producing bacteria, Lactobacillus paracasei JS1, was analyzed. Also, the effect of P. lobata extract fermented with L. paracasei JS1 (FPE) on the skin and intestinal immune response was examined. With gene expression analysis, it was proven that seven skin‐related proteins, hyaluronan synthase‐1, ‐2, ‐3, collagen, elastin, epidermal growth factor, and epidermal growth factor receptor were differentially expressed upon FPE treatment. The messenger RNA expression increased with treatment with the FPE, and a skin moisturizing effect was confirmed by a hematoxylin–eosin staining experiment. In addition, such an experiment showed that proinflammatory cytokines, tumor necrosis factor‐α, cyclooxygenase‐2, inducible nitric oxide synthase, interleukin‐1β, ‐4, and ‐6, were reduced in large intestine when treated with FPE. CONCLUSION: L. paracasei JS1 has the ability to produce equol having beneficial effects on the skin. Moreover, FPE also has an inhibitory effect on inflammation cytokines in the large intestine. Thus, the novel and edible equol‐producing L. paracasei JS1 and FPE have thepotential to be developed as nutricosmetic resources. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: In response to the demand for flexible and sustainable energy storage devices that exhibit high electrochemical performance, a supercapacitor system is fabricated using mulberry tree‐derived paper as a substrate and Poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) and carbon black as the active material. The mulberry paper‐based supercapacitor system demonstrates high energy density of 29.8–39.8 Wh kg−1 and power density of 2.8–13.9 kW kg−1 with 90.7% retention of its initial capacity over 15 000 charge–discharge cycles. In addition, the mulberry tree fibers are known to have superior mechanical strength and toughness and the mulberry paper‐based supercapacitor; as a result, exhibit high mechanical and chemical toughness; 99% of its initial capacity is retained after 100 repeated applications of bending strains, and twisting. 94% capacity retention is observed even after exposure to HCl and H2SO4 acid solutions. The fabrication methodology of the mulberry‐based supercapacitor is highly scalable and could be stacked to increase the energy storage capacity, where operation of light‐emitting diode lights with a drive voltage of 12 V integrated in a wearable device is demonstrated. [ABSTRACT FROM AUTHOR]

Summary: Clavibacter michiganensis ssp. capsici is a Gram‐positive plant‐pathogenic bacterium causing bacterial canker disease in pepper. Virulence genes and mechanisms of C. michiganensis ssp. capsici in pepper have not yet been studied. To identify virulence genes of C. michiganensis ssp. capsici, comparative genome analyses with C. michiganensis ssp. capsici and its related C. michiganensis subspecies, and functional analysis of its putative virulence genes during infection were performed. The C. michiganensis ssp. capsici type strain PF008 carries one chromosome (3.056 Mb) and two plasmids (39 kb pCM1Cmc and 145 kb pCM2Cmc). The genome analyses showed that this bacterium lacks a chromosomal pathogenicity island and celA gene that are important for disease development by C. michiganensis ssp. michiganensis in tomato, but carries most putative virulence genes in both plasmids. Virulence of pCM1Cmc‐cured C. michiganensis ssp. capsici was greatly reduced compared with the wild‐type strain in pepper. The complementation analysis with pCM1Cmc‐located putative virulence genes showed that at least five genes, chpE, chpG, ppaA1, ppaB1 and pelA1, encoding serine proteases or pectate lyase contribute to disease development in pepper. In conclusion, C. michiganensis ssp. capsici has a unique genome structure, and its multiple plasmid‐borne genes play critical roles in virulence in pepper, either separately or together. [ABSTRACT FROM AUTHOR]

Alkoxy side-chain tethered polyfluorene conjugated polyelectrolyte (CPE), poly[(9,9-bis((8-(3-methyl-1-imidazolium)octyl)-2,7-fluorene)-alt-(9,9-bis(2-(2-methoxyethoxy)ethyl)-fluorene)] dibromide (F8imFO4), is utilized to obtain CPE-hybridized ZnO nanoparticles (NPs) (CPE:ZnO hybrid NPs). The surface defects of ZnO NPs are passivated through coordination interactions with the oxygen atoms of alkoxy side-chains and the bromide anions of ionic pendent groups from F8imFO4 to the oxygen vacancies of ZnO NPs, and thereby the fluorescence quenching at the interface of yellow-emitting poly( p-phenylene vinylene)/CPE:ZnO hybrid NPs is significantly reduced at the CPE concentration of 4.5 wt%. Yellow-emitting polymer light-emitting diodes (PLEDs) with CPE(4.5 wt%):ZnO hybrid NPs as a cathode interfacial layer show the highest device efficiencies of 11.7 cd A−1 at 5.2 V and 8.6 lm W−1 at 3.8 V compared to the ZnO NP only (4.8 cd A−1 at 7 V and 2.2 lm W−1 at 6.6 V) or CPE only (7.3 cd A−1 at 5.2 V and 4.9 lm W−1 at 4.2 V) devices. The results suggest here that the CPE:ZnO hybrid NPs has a great potential to improve the device performance of organic electronics. [ABSTRACT FROM AUTHOR]

For the first time, highly efficient and flexible polymer light emitting diodes (PLEDs) based on silver nanowire (AgNW) electrode, with improved operational stability by simply applying pre-bias conditioning treatment, are demonstrated. Reverse bias conditioning performed before J-V-L measurement of the PLEDs enables the rough AgNW networks to function properly as a bottom electrode by stabilizing current characteristics, and the devices continue to show consistent operational performances. Conditions of applied bias and thicknesses of active layer are controlled for optimization and it is found that high reverse voltage is required to obtain current stabilization. Adequate thickness of polymer is also necessary to avoid breakdown induced by reverse bias. The essential effect of pre-bias conditioning on the improved performances of PLEDs is investigated, and it is found that morphological change of AgNW networks contribute to the improvement in device performance. Some of the AgNWs that appear to be pathway of leakage current are deformed, and surface roughness (RMS) of the AgNW film is decreased while the sheet resistance of the film is maintained when the reverse bias conditioning is applied. It is also revealed that pre-bias conditioning is independent from directionality of the applied bias when utilizing insulating polymer sandwiched between two electrodes. [ABSTRACT FROM AUTHOR]

The workfunction of graphene was modified using solution-processed molybdenum oxide (MoOx) resulting in efficient charge injection in PLED. After the doping, the sheet resistance of five-layer graphene with optical transmittance of ~88 % was as low as ~180 Ω sq-1. Compared with the pristine graphene, maximum current efficiency was enhanced by 255 %. [ABSTRACT FROM AUTHOR]

Graphene has been considered to be a potential alternative transparent and flexible electrode for replacing commercially available indium tin oxide (ITO) anode. However, the relatively high sheet resistance and low work function of graphene compared with ITO limit the application of graphene as an anode for organic or polymer light-emitting diodes (OLEDs or PLEDs). Here, flexible PLEDs made by using bis(trifluoromethanesulfonyl)amide (TFSA, [CF3SO2]2NH) doped graphene anodes are demonstrated to have low sheet resistance and high work function. The graphene is easily doped with TFSA by means of a simple spin-coating process. After TFSA doping, the sheet resistance of the TFSA-doped five-layer graphene, with optical transmittance of ≈88%, is as low as ≈90 Ω sq−1. The maximum current efficiency and power efficiency of the PLED fabricated on the TFSA-doped graphene anode are 9.6 cd A−1 and 10.5 lm W−1, respectively; these values are markedly higher than those of the PLED fabricated on pristine graphene anode and comparable to those of an ITO anode. [ABSTRACT FROM AUTHOR]

A significant volume expansion exhibited by high‐capacity active materials upon lithiation has hindered their application as Li‐ion battery anode materials. Although tremendous progress has been made in the development of coating methods that improve the stability of high‐capacity active materials, suitable coating sources that are both strong and economical to use are yet to be discovered. Pitch is reported here as a promising coating source for high‐capacity anodes owing to the high mechanical strength and low‐cost process. Using in situ transmission electron microscopy, it is found that pitch can withstand the severe volume expansion that occurs upon Si lithiation owing to its high mechanical strength, originating from the long‐range graphitic ordering. Notably, pitch‐coated silicon nanolayer–embedded graphite (SG) exhibits superior capacity retention (81.9%) compared to that of acetylene‐coated SG (66%) over 200 cycles in a full‐cell by effectively mitigating volume expansion, even under industrial electrode density conditions (1.6 g cc−1). Thus, this work presents new possibilities for the development of high‐capacity anodes for industrial implementation. With state‐of‐the‐art in situ techniques and fundamental studies, petroleum‐derived pitch demonstrates potential as coating source which addresses mechanical and economic issues of Si anodes. Under industrial electrode conditions, pitch‐coated Si nanolayer–embedded graphite exhibits superior structural and electrochemical stability than other carbon‐coated SGs. This work presents a new breakthrough for practical implementation of the high‐capacity anodes. [ABSTRACT FROM AUTHOR]