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This study mainly is carried out to discuss the effect of nitrogen annealing temperature on perovskite solar cells. The annealing temperature affects perovskite solar cells during the annealing process. It also affects the formation of perovskite crystals. Perovskite crystals need to form in a nitrogen box for manufacturing Perovskite solar cells. Spin-coating MAPbI3 on the substrate is annealed with a nitrogen furnace tube to form perovskite crystals. The remaining PbI2 after the annealing is completed to improve the efficiency of perovskite solar cells. The optimal temperature for the formation of perovskite crystals is found by adjusting the annealing temperature. By using UV-visible spectrometer, field emission-scanning electron microscope, and measurements of photoelectric conversion efficiency, cell structure and optoelectronic properties are analyzed as the final results.

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 Na(2)SeO(4) 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

Optimal selenium (Se) status is necessary for overall health. That status can be affected by food intake pattern, age, sex, and health status. At nutritional levels of intake, Se functions metabolically as an essential constituent of some two dozen selenoproteins, most, if not all, of which have redox functions. Insufficient dietary intake of Se reduces, to varying degrees, the expression of these selenoproteins. Recent clinical and animal studies have indicated that both insufficient and excessive Se intakes may increase risk of type 2 diabetes mellitus (T2D), perhaps by way of selenoprotein actions. In this review, we discuss the current evidence linking Se status and T2D risk, and the roles of 14 selenoproteins and other proteins involved in selenoprotein biosynthesis. Understanding such results can inform the setting of safe and adequate Se intakes.

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[Formula: see text]N4 concentrations on the synthesized characteristics of ZnO nanorods. First, the ZnO gel was dipped on the surface of the [Formula: see text]-type [Formula: see text] wafer as a seed layer. Then, the hydrothermal method with different Zn(CH3COO)2 and C6H[Formula: see text]N4 concentrations as precursors was used to synthesize ZnO nanorods on [Formula: see text]-type [Formula: see text] 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. [Formula: see text]C and 60 min were used as the synthesis temperature and time, and we found that Zn(CH3COO)2 and C6H[Formula: see text]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[Formula: see text]N4 concentrations of 0.2 M. The results of XRD patterns suggest that ZnO nanorods have the property of [Formula: see text]-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[Formula: see text], total volume (V, nm[Formula: see text], S/V ratio, and PL property of ZnO nanorods.

The classic likelihood ratio test for testing the equality of two covariance matrices breakdowns due to the singularity of the sample covariance matrices when the data dimension is larger than the sample size. In this paper, we present a conceptually simple method using random matrices to project the data onto a one-dimensional random subspace so that conventional methods can be applied. Both one-sample and two-sample tests for high-dimensional covariance matrices are considered. A transformation using the precision matrix is used to help maintain the information on the off-diagonal elements of the covariance matrices. Multiple projections are used to improve the performance of the proposed tests. An extremal type theorem is established and used to estimate the significance level. Simulations and an application to the Acute Lymphoblastic Leukemia (ALL) data are given to illustrate our method.

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.

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 ([Formula: see text], conversion efficiency ([Formula: see text]), and decreases the internal structure impedance ([Formula: see text]) of DSSCs. [Formula: see text] increases from 13.62 to 17.02, 15.22, 16.05 mA/cm2, while [Formula: see text] (%) 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 [Formula: see text] from 11.28 to 8.36, 8.78, 8.54 [Formula: see text], respectively. Then, the titanium dioxide (TiO[Formula: see text]-doped G-GQDs, G-Au, and QDs-Au on DSSCs influence [Formula: see text] that increases to 5.45, 15.37, and 15.31 mA/cm2, respectively. In this case, the values of [Formula: see text] are found to be 7.21%, 7.35%, and 7.00%, while those of [Formula: see text] are 8.44, 8.63, and 9.18 [Formula: see text]. The values of [Formula: see text] and [Formula: see text] are highest but that of [Formula: see text] 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.

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 [Formula: see text] decreased from 12.086 [Formula: see text] (without graphene doping) to 9.875 [Formula: see text] 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.%.

This paper introduces a three-dimensional light field display system, which is composed of a high-speed projector, a directional scattering mirror, a circular stainless-steel bearing plate, a rotating shaft and a high-speed micro motor. The system reduces information redundancy and computational complexity by reconstructing the light intensity distribution of the observed object, thus generating a real three-dimensional suspended image. The experimental results show that the suspension three-dimensional image can be generated by properly adjusting the projection rate of the image and the rotation speed of the rotating mirror (i.e. the motor speed). The clarity and accuracy of a three-dimension display depending on the number of slices selected, meaning that the more slices can be projected per minute, the finer the three-dimension display. Finally, this study provides the basic parameter matching, which shows the feasibility of developing a real light field 3D display system with stable performance, strong portability, easy implementation, and low cost. In short, naked-eye 3D allows the observer to view objects from any angle and direction, without the need for any auxiliary tools (such as glasses, helmets, etc.).

The biology and physiology of Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae), also known as the ham, cheese or mold mite, is reviewed along with methods that have been evaluated for managing and controlling this pest. This review was conducted because the ham mite is an important target pest of the dry cured ham industry. Methyl bromide has been historically used to control mite infestations, but is now banned or being phased out of use in most countries because it is an ozone-depleting substance. Only commercially available stockpiles and quarantine and pre-shipment methyl bromide are available for use in countries that require such action. This review compares the effectiveness and feasibility of recently investigated methods to control mite infestations on dry cured ham and to discuss integrated pest management plans for ham mites. The review also proposes methods for conducting a prevention and monitoring-based integrated pest management program that relies on definitive mitigation such as fumigation only when mite numbers exceed a critical action threshold.

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.

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, Erdos 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.

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.

In this paper, the distributions of scan statistics of inhomogeneous Poisson processes are studied. First, the distribution of the continuous scan statistic of an inhomogeneous Poisson process is approximated by the distribution of the discrete scan statistic for a sequence of Bernoulli trials with unequal probabilities of success. Next, we introduce a weighted scan statistic to adjust the inhomogeneity and the weighted continuous scan statistic is also approximated by the weighted discrete scan statistic. The finite Markov chain imbedding technique is used to obtain the exact distributions of weighted discrete scan statistics. An example using the weighted scan statistic of an inhomogeneous Poisson process for detecting DNA copy number variation is given. Numerical results and simulations are also given to illustrate our theoretical results.

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 RK 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/cm2 and ZnO composite structure. The best structure is ZnO composite structure, and it has the best current density (JSC = 10.59 mA/cm2) and overall conversion efficiency (η = 3.46%) of dye-sensitized solar cells.

In this study, educational social learning theory and a statistical multiple-criteria decisionmaking (MCDM) methodology are creatively cross-employed to comprehensively cross-evaluate online courses and sensor technologies. This was accomplished by means of an in-depth survey of large-scale current online-course users and professional experts with the highest research reliability, validity, accuracy, and representativeness. The three most valuable and contributive conclusions of this study are as follows: (1) The repurposing technology function (RTF) of online-course technology can combine software sensor (SS), motion sensor (MS), and environment sensor (ES) technologies to not only detect moving objects but also achieve cognition in the environment (e.g., by using a face sensor) to extract emotions of course participants in response to words and phrases during lectures to increase online-course learning performance. (2) The course professionalization technology function (CPTF) of online-course technology can merge SS, MS, and ES technologies to control online-course hardware sensor devices and equipment to control the depth and span of online-course content to strengthen online-course learning performance. (3) The course evaluation technology function (CETF) of online-course technology can consolidate SS, MS, and ES technologies to not only empirically evaluate online-course implementation but also indirectly appraise online-course learning performance. © 2021 M Y U Scientific Publishing Division. All rights reserved.

In this study, we investigated the effect of doping zinc oxide (ZnO) microrods on fluorine-doped tin oxide (FTO) conductive glass without seed layer and its characteristics at the photo electrode of dye-sensitized solar cell (DSSC). Octadecyltrimethoxysilane (ODS; CH 3 (CH 2 ) 17 Si(OCH 3 ) 3 ) deposited on the substrate form a self-assembled monolayer by to enhance the following growth of ZnO microrods. 0.03M of zinc nitrate hexahydrate (Zn(NO 3 ) 2 ·6H 2 O) and 0.03 M hexamethylene tetramine (C 6 H 12 N 4 , HMT) were the main reaction materials in the hydrothermal method. In this experiment, the ZnO mircorods was doped with gallium, using the gallium nitrate (Ga(NO 3 ) 3 ) of 0.15 to 0.60 mM. The ZnO microrods applied for DSSCs analyzed by FE-SEM, UV-Vis spectra and I–V curves.

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.

In this study, a loader drive axle digital model was built using 3D commercial software. On the basis of this model, the transmission efficiency of the main reducing gear, the differential planetary mechanism, and the wheel planetary reducing gear of the loader drive axle were studied. The functional relationship of the transmission efficiency of the loader drive axle was obtained, including multiple factors: the mesh friction coefficient, the mesh power loss coefficient, the normal pressure angle, the helix angle, the offset amount, the speed ratio, the gear ratio, and the characteristic parameters. This revealed the influence law of the loader drive axle by the mesh friction coefficient, mesh power loss coefficient, and speed ratio. The research results showed that the transmission efficiency of the loader drive axle increased with the speed ratio, decreased when the mesh friction coefficient and the mesh power loss coefficient increased, and that there was a greater influence difference on the transmission efficiency of the loader drive axle.

The distributions of discrete, continuous and conditional multiple window scan statistics are studied. The finite Markov chain imbedding technique has been applied to obtain the distributions of fixed window scan statistics defined from a sequence of Bernoulli trials. In this manuscript the technique is extended to compute the distributions of multiple window scan statistics and the exact powers for multiple pulse and Markov dependent alternatives. An application in blood component quality monitoring is provided. Numerical results are also given to illustrate our theoretical results.

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.

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.

We propose a new method to obtain the boundary crossing probabilities or the first passage time distribution for linear and nonlinear boundaries for Brownian motion. The method also covers certain classes of stochastic processes associated with Brownian motion. The basic idea of the method is based on being able to construct a finite Markov chain, and the boundary crossing probability of Brownian motion is cast as the limiting probability of the finite Markov chain entering a set of absorbing states induced by the boundaries. Error bounds are obtained. Numerical results for various types of boundary studied in the literature are provided in order to illustrate our method.

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.