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In this study, an ultra-wideband absorber spanning from UV-B to middle-IR was designed and analyzed using a novel structure. The multilayer metamaterial, arranged from bottom to top, consisted of an Al metal layer, a lower SiO2 layer, a graphite layer, another SiO2 layer, a thin Ti layer, and a top SiO2 layer. The top layer of SiO2 had a 200 nm square cavity etched out, and then a square Ti nanopillar and a square Ti hollow outside a Ti nanopillar were embedded. This specific arrangement was chosen to maximize the absorption properties across a broad spectrum. The absorption spectrum of the designed absorber was thoroughly analyzed using the commercial finite element analysis software COMSOL Multiphysics® (version 6.0). This analysis confirmed that the combination of these various components achieved perfect absorption and an ultra-wideband response. The synergistic interaction between the layers and the nanopillars structure contributed significantly to the absorber's efficiency, making it a promising candidate for applications requiring broad-spectrum absorption. The comprehensive analyses of the parameters for different structures demonstrated that the effects of guided-mode resonance, coupling resonance, optical impedance matching, and propagating surface plasmon resonance existed in the investigated structure. The optimal model, determined through analyses using COMSOL Multiphysics®, showed that the broadband absorption in the range of 270 to 3600 nm, spanning from UV-B to middle-IR, exceeded 90.0%. The average absorption rate within this range was 0.967, with the highest reaching a near-perfect absorptivity of 99.9%. We also compared three absorption spectra in this study: the t1–t6 flat structure, the t1–t5 flat structure with t6 featuring a square cavity, and the structure proposed in this study. This demonstrates that a square nanopillar and a square hollow embedded in a square cavity can enhance the absorptive properties of the absorber. [ABSTRACT FROM AUTHOR]

In this study, the sol–gel method was used to prepare ZnO seed layer for synthesizing ZnO nanorods, and we would investigate the effects of different Zn(CH3COO)2 and C6H 1 2 N4 concentrations on the synthesized characteristics of ZnO nanorods. First, the ZnO gel was dipped on the surface of the P -type Si 〈 1 0 0 〉 wafer as a seed layer. Then, the hydrothermal method with different Zn(CH3COO)2 and C6H 1 2 N4 concentrations as precursors was used to synthesize ZnO nanorods on P -type Si 〈 1 0 0 〉 wafer. X-ray diffraction (XRD) pattern, focused ion beam-field emission scanning electron microscopy (FIB-FESEM) and photoluminescence (PL) spectrometry were employed to observe and analyze the crystal properties, surface morphologies, and optical properties of the prepared ZnO seed layer and synthesized ZnO nanorods. 9 0 ∘ C and 60 min were used as the synthesis temperature and time, and we found that Zn(CH3COO)2 and C6H 1 2 N4 concentrations had an apparent effect on the height, diameter, total surface area, total volume, density, and PL property of ZnO nanorods. The maximum PL emission intensity of ZnO nanorods presented in the samples with Zn(CH3COO)2 and C6H 1 2 N4 concentrations of 0.2 M. The results of XRD patterns suggest that ZnO nanorods have the property of c -axis preferred orientation. We showed that the different Zn(CH3COO)2 concentrations had large effects on the average height, average diameter, aspect ratio, total surface area (S, nm 2) , total volume (V, nm 3) , S/V ratio, and PL property of ZnO nanorods. [ABSTRACT FROM AUTHOR]

The management of peptic ulcer bleeding is clinically challenging. For decades, the Forrest classification has been used for risk stratification for nonvariceal ulcer bleeding. The perception and interpretation of the Forrest classification vary among different endoscopists. The relationship between the bleeder and ulcer images and the different stages of the Forrest classification has not been studied yet. Endoscopic still images of 276 patients with peptic ulcer bleeding for the past 3 years were retrieved and reviewed. The intra-rater agreement and inter-rater agreement were compared. The obtained endoscopic images were manually drawn to delineate the extent of the ulcer and bleeding area. The areas of the region of interest were compared between the different stages of the Forrest classification. A total of 276 images were first classified by two experienced tutor endoscopists. The images were reviewed by six other endoscopists. A good intra-rater correlation was observed (0.92–0.98). A good inter-rater correlation was observed among the different levels of experience (0.639–0.859). The correlation was higher among tutor and junior endoscopists than among experienced endoscopists. Low-risk Forrest IIC and III lesions show distinct patterns compared to high-risk Forrest I, IIA, or IIB lesions. We found good agreement of the Forrest classification among different endoscopists in a single institution. This is the first study to quantitively analyze the obtained and explain the distinct patterns of bleeding ulcers from endoscopy images. [ABSTRACT FROM AUTHOR]

The doctor blade coating method is used to prepare dye-sensitized solar cells (DSSCs) and dope the original titanium dioxide (TiO2, P25) photoanode (PA) with single-layer graphene (G), graphene quantum dots (GQDs), and gold (Au) nanoparticles in this research. The results show that doping PAs with G, GQDS, and Au effectively increases the short-circuit current density ( J sc ) , conversion efficiency (η), and decreases the internal structure impedance ( R k ) of DSSCs. J sc increases from 13.62 to 17.02, 15.22, 16.05 mA/cm2, while η (%) increases from 6.36 to 7.50, 7.08, 7.04% when doping G, GQDs, and Au, respectively. The analysis of Electrochemical Impedance Spectroscopy (EIS) reveals that the doping decreases R k from 11.28 to 8.36, 8.78, 8.54 Ω , respectively. Then, the titanium dioxide (TiO 2) -doped G-GQDs, G-Au, and QDs-Au on DSSCs influence J sc that increases to 5.45, 15.37, and 15.31 mA/cm2, respectively. In this case, the values of η are found to be 7.21%, 7.35%, and 7.00%, while those of R k are 8.44, 8.63, and 9.18 Ω. The values of J sc and η are highest but that of R k are lowest when doping with G, which proves that the photoanode of the DSSC effectively activates the photogenerated electrons in the film by doping single-layer graphene and TiO2 captures its electrons through graphene. The decreasing electron–hole recombination rate allows the photogenerated electrons to be quickly transferred to the external circuit. As a result, the efficiency of DSSCs is improved. [ABSTRACT FROM AUTHOR]

This study explores the influence of molar ratio of the synthetic solution of methylammonium iodide (MAI) and PbI2 on perovskite solar cells. The complete perovskite crystals must be produced in a low-humidity environment. The substrate is spin-coated in the adjusted MAPbI3 synthesis solution and annealed by using a nitrogen furnace tube to form perovskite crystals. During the crystallization of MAPbI3, some of the PbI2 remains, which improves the efficiency of the perovskite solar cell. Therefore, we adjust the molar concentration of MAI to find the appropriate amount of the PbI2 residual. We fix the MAI molar concentration at 1 M and adjust the PbI2 molar concentration from 0.8 M to 1.4 M. The molar ratios of MAI and PbI2 are, then, 1:0.8, 1:1, 1:1.2, and 1:1.4, respectively. Then, we use UV–vis, FE-SEM, and photoelectric conversion efficiency (PCE) measurements for comparing the growth of perovskite crystals and their photoelectric characteristics. The results show that 1.2 M of PbI2 is the most appropriate concentration for perovskite solar cells among the adjusted concentrations. [ABSTRACT FROM AUTHOR]

The scattering layer in the TiO2 photoanode (PAs) of dye-sensitized solar cells (DSSCs) is doped with single-layer graphene (G), and DSSC is prepared by doctor blade coating method. A small amount of graphene (0.0016 wt.%) in a graphene aqueous solution (G-AS) and a G-TiO2 paste was prepared to make 2–20 wt.% of G-AS in the deionized water (DIW). The UV-Vis measurement results show that the TiO2 scattering layers doped with graphene effectively improve the visible light absorption intensity of DSSC PAs and increase the current density (Jsc) from 13.84 mA/cm2 to 16.20 mA/cm2. The Electrochemical Impedance Spectroscopy (EIS) measurement showed that the internal structural impedance Rk (Ω) decreased from 12.086 (Ω) (without graphene doping) to 9.875 (Ω) at 5 wt.% of the graphene doping. The photoelectric conversion efficiency (PCE) increased from 6.56% of the original un-doped graphene to the maximum PCE value of 7.57% at 5 wt.%. The results show that the best PCE is obtained when the concentration of G-AS is 5 wt.%. [ABSTRACT FROM AUTHOR]

Background: Although dietary selenium (Se) deficiency or excess induces type 2 diabetes-like symptoms in mice, suboptimal body Se status usually causes no symptoms but may promote age-related decline in overall health.Objectives: We sought to determine the dietary Se requirement for protection against type 2 diabetes-like symptoms in mice.Methods: Thirty mature (aged 4 mo) male C57BL/6J mice were fed a Se-deficient torula yeast AIN-93M diet supplemented with Na2SeO4 in graded concentrations totaling 0.01 (basal), 0.04, 0.07, 0.10, and 0.13 (control) mg Se/kg for 4 mo (n = 6) until they were middle-aged (8 mo). Droplets of whole blood were used to determine glucose tolerance and insulin sensitivity in the mice from ages 5 to 8 mo. Postmortem serum, liver, and skeletal muscle were collected to assay for selenoprotein expression and markers of glucose metabolism. Data were analyzed by 1-way ANCOVA with or without random effects for time-repeated measurements using live mice or postmortem samples, respectively.Results: Compared with control, the consumption of basal diet increased (P < 0.05) fasting serum insulin (95% CI: 52%, 182%) and leptin (95% CI: 103%, 118%) concentrations in middle-aged mice. Dietary Se insufficiency decreased (P < 0.05) 1) glucose tolerance (13-79%) and insulin sensitivity (15-65%) at ≤0.10 mg Se/kg; 2) baseline thymoma viral proto-oncogene phosphorylation on S473 (27-54%) and T308 (22-46%) at ≤0.10 and ≤0.07 mg Se/kg, respectively, in the muscle but not the liver; and 3) serum glutathione peroxidase 3 (51-83%), liver and muscle glutathione peroxidase 1 (32-84%), serum and liver selenoprotein P (28-42%), and liver and muscle selenoprotein H (39-48%) and selenoprotein W (16-73%) protein concentrations at ≤0.04, ≤0.10, ≤0.07, and ≤0.10 mg Se/kg, respectively.Conclusions: Mice fed diets containing ≤0.10 mg Se/kg display impaired glucose tolerance and insulin sensitivity, suggesting increased susceptibility to type 2 diabetes by suboptimal Se status at levels ≤23% of nutritional needs. [ABSTRACT FROM AUTHOR]

In this paper, a simple and general method based on the finite Markov chain imbedding technique is proposed to determine the exact conditional distributions of runs and patterns in a sequence of Bernoulli trials given the total number of successes. The idea is that given the total number of successes, the Bernoulli trials are viewed as random permutations. Then, we extend the result to multistate trials. The conditional distributions studied here lead to runs and patterns-type distribution-free tests whose applications are widespread. Two applications are considered. First, a distribution-free test for randomness is applied to rainfall data at Oxford from 1858 to 1952. The second application is to develop runs and patterns-type distribution-free control charts which can be used as Phase I and/or Phase II control charts. Numerical results for two commonly used runs-type statistics, the longest run and scan statistics, are also given. [ABSTRACT FROM AUTHOR]

The finite Markov chain imbedding technique has been used to compute the boundary crossing probabilities of one and higher-dimensional Brownian motion. The idea is to cast the boundary crossing probabilities as the limiting probabilities of a finite Markov chain entering a set of absorbing states induced by the boundaries. In this manuscript, we extend the technique to compute the boundary crossing probabilities of a class of jump diffusion processes to time-dependent boundaries. We allow the jump sizes to have general distributions and the boundaries to be non-linear. Numerical examples are given to illustrate our theoretical results. [ABSTRACT FROM AUTHOR]

The finite Markov chain imbedding technique is an emerging approach for calculating boundary crossing probabilities for high-dimensional Brownian motion and certain one-dimensional diffusion processes. In 1996, Erdös and Kac produced an infinite series for the crossing probability of Brownian motion over a two-sided constant boundary. We derive this classic result based on a unified formula from the finite Markov chain imbedding technique. Also, an eigenvalues-and-eigenvectors approximation is given for fast computation. The main purpose of this paper is to show the versatility of the finite Markov chain imbedding technique. [ABSTRACT FROM AUTHOR]

In this study, we prepared low-density ZnO micron rods (MRs) on ITO/PEN substrate by hydrothermal method, and used the scraper to fill the ZnO nanoparticles into the micron rods to prepare ZnO composite structure as the photo-electrode of dye sensitized solar cells (DSSCs). The nanostructures and photo-electrodes were investigated by field emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS), incident photon conversion efficiency (IPCE) and I-V characteristics analyses. In the results of FE-SEM, they show that the average length of the ZnO MRs and the thickness of ZnO film are 14 and 33.1 μm, respectively. EIS analyses show that there is a minimal R and the longest electron lifetime of DSSCs with the ZnO composite structure, which means less recombination of the electrons in the ZnO composite structure. The results of IPCE indicate that the photo-electrode of ZnO composite structure exhibits the best quantum efficiency about 81.7%. It may be due to ZnO MRs play as a light scattering layer resulting in the increase of path length for the incident light, thereby increasing the collision probability between the incident light and the ZnO nanoparticles. In addition, we also compared the I-V characteristics of three different photo-electrodes with ZnO NPs, ZnO NPs pressed 418.8 kg/cm and ZnO composite structure. The best structure is ZnO composite structure, and it has the best current density (J = 10.59 mA/cm) and overall conversion efficiency (η = 3.46%) of dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

Background: The hierarchies of tissue selenium distribution and selenotranscriptomes are thought to critically affect healthspan and longevity.Objective: We determined selenium status and selenotranscriptomes in response to long-term dietary selenium deficiency and age in tissues of male and female mice.Methods: Weanling telomerase RNA component knockout C57BL/6 mice were fed a selenium-deficient (0.03 mg Se/kg) Torula yeast-based AIN-93G diet or a diet supplemented with sodium selenate (0.15 mg Se/kg) until age 18 or 24 mo. Plasma, hearts, kidneys, livers, and testes were collected to assay for selenotranscriptomes, selected selenoproteins, and tissue selenium concentrations. Data were analyzed with the use of 2-factor ANOVA (diet × age) in both sexes.Results: Dietary selenium deficiency decreased (P ≤ 0.05) selenium concentrations (65-72%) and glutathione peroxidase (GPX) 3 (82-94%) and selenoprotein P (SELENOP) (17-41%) levels in the plasma of both sexes of mice and mRNA levels (9-68%) of 4, 4, and 12 selenoproteins in the heart, kidney, and liver of males, respectively, and 5, 16, and 14 selenoproteins, respectively, in females. Age increased selenium concentrations and SELENOP levels (27% and 30%, respectively; P ≤ 0.05) in the plasma of males only but decreased (12-46%; P < 0.05) mRNA levels of 1, 5, and 13 selenoproteins in the heart, kidney, and liver of males, respectively, and 6, 5, and 0 selenoproteins, respectively, in females. Among these mRNAs, selenoprotein H (Selenoh), selenoprotein M (Selenom), selenoprotein W (Selenow), methionine-R-sulfoxide reductase 1 (MsrB1), Gpx1, Gpx3, thioredoxin reductase 1 (Txnrd1), Txnrd2, selenoprotein S (Selenos), selenoprotein F (Selenof), and selenoprotein O (Selenoo) responded in parallel to dietary selenium deficiency and age in ≥1 tissue or sex, or both. Dietary selenium deficiency upregulated (40-160%; P ≤ 0.05) iodothyronine deiodinase 2 (Dio2) and selenoprotein N (Selenon) in the kidneys of males. Age upregulated (11-44%; P < 0.05) Selenon in the kidneys of males, selenoprotein K (Selenok) and selenoprotein I (Selenoi) in the kidneys of females, and Selenof and Selenok in the testes.Conclusions: These results illustrate tissue-specific sexual dimorphisms of selenium status and selenotranscriptomes because of dietary selenium deficiency and age. [ABSTRACT FROM AUTHOR]

B Video 1 b Capsule endoscopy of an 84-year-old woman, showing a bleeding polypoid lesion in the jejunum. In this case, the bleeding intestinal lymphangioma was successfully diagnosed by capsule endoscopy and treated by resection during enteroscopy. [Extracted from the article]

The finite Markov Chain Imbedding technique has been successfully applied in various fields for finding the exact or approximate distributions of runs and patterns under independent and identically distributed or Markov dependent trials. In this paper, we derive a new recursive equation for distribution of scan statistic using the finite Markov chain imbedding technique. We also address the problem of obtaining transition probabilities of the imbedded Markov chain by introducing a notion termed Double Finite Markov Chain Imbedding where transition probabilities are obtained by using the finite Markov chain imbedding technique again. Applications for random permutation model in chemistry and coupon collector's problem are given to illustrate our idea. [ABSTRACT FROM AUTHOR]

In this paper, recursive equations for waiting time distributions of r-th occurrence of a compound pattern are studied via the finite Markov chain imbedding technique under overlapping and non-overlapping counting schemes in sequences of independent and identically distributed (i.i.d.) or Markov dependent multi-state trials. Using the relationship between number of patterns and r-th waiting time, distributions of number of patterns can also be obtained. The probability generating functions are also obtained. Examples and numerical results are given to illustrate our theoretical results. [ABSTRACT FROM AUTHOR]

It is well known that statistical control charts such as Shewhart, CUSUM and EWMA charts have widespread applications in improving the quality for manufacturing and service systems. The average run length is a traditional measurement of a control chart's performance. Usually, finding the run length distribution and the average run length is a difficult and tedious task. In this article, we develop a general and unified approach based on the use of discretization and the finite Markov chain imbedding technique to investigate the run length properties for various control charts when the process observations are autocorrelated. Numerical results are presented for illustrative purposes. [ABSTRACT FROM AUTHOR]