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Purpose: The maelstrom spermatogenic transposon silencer (MAEL) function in postmeiotic germ cells remains unclear, and its protein localization in human testis and spermatozoa awaits determination. This study aims to clarify the MAEL expression in human spermatogenesis and to explore its role in sperm function. Materials and methods: Twenty‐seven asthenozoospermic men, 40 normozoospermic controls, and three obstructive azoospermic men were enrolled. The transcripts of MAEL in the seminiferous epithelium and MAEL downstream targets were identified by bioinformatics analysis. MAEL protein expression in human testis and ejaculated sperms were examined by immunohistochemical and immunogold staining, respectively. The roles of MAEL in mitochondria function were investigated by siRNA knockdown in human H358 cells. The association between MAEL protein levels and clinical sperm features was evaluated. Results: Abundant MAEL was expressed in spermatid and spermatozoa of the human testis. Remarkably, MAEL was located in the mitochondria of ejaculated sperm, and bioinformatics analysis identified GPX4 and UBL4B as MAEL's downstream targets. Knockdown of MAEL sabotaged mitochondria function and reduced adenosine triphosphate (ATP) production in H358 cells. MAEL, GPX4, and UBL4B expression levels were significantly decreased in asthenozoospermic sperms than in controls. The MAEL protein levels were positively correlated with GPX4 and UBL4B in human sperm. Total motile sperm count (TMSC) was positively correlated with protein levels of MAEL, GPX4, and UBL4B in ejaculated sperms. Conclusions: We highlight prominent MAEL expression in the intratesticular spermatid and the mitochondria of ejaculated spermatozoa. MAEL directly binds to GPX4 and UBL4B, and loss of MAEL induces mitochondrial dysfunction. MAEL‐mitochondrial function‐motility relationship might advance our understanding of the causes of asthenozoospermia. [ABSTRACT FROM AUTHOR]

The finite-difference time-domain (FDTD) method is successfully used to calculate the electric fields radiated from a prototype of a R J45 connector for Ethernet transmission. Simulation results of the electric fields radiated from the prototype of this R J45 connector are validated by measurement data for vertical and horizontal polarizations in 300 ~ 1000 MHz frequency range. It is also found that simulation and measurement results for both vertical and horizontal polarizations are over the regulation limit at 600 MHz. In order to meet regulation limits, further studies are also conducted by taking numerous possible affecting factors on radiated electric fields into consideration for FDTD simulations; these include the aperture area, the location of the excitation, the material used for the aperture, enclosures with and without grounding. From simulation results presented in this paper, it is found that the magnitude of the higher emission levels can be reduced by reducing the aperture area, putting the location of excitation deeper into the connector, using materials with smaller dielectric constants and conductivities for the aperture, and adding a grounding enclosure on the R J45 connector. Index Terms--Connector, Ethernet transmission, finite-difference time-domain (FDTD), radiated fields.

A new series of new iridium (III) complexes (1-5) bearing ligands derived from benzoquinoxaline were designed and synthesized. X-ray structural analyses of 1 reveal a distorted octahedral geometry around the Ir atom in which the pyrazolate chelate is located opposite to the cis-oriented carbon donor atoms of benzoquinoxaline, while the benzoquinoxaline ligands adopt an eclipse configuration and their coordinated nitrogen atoms and carbon adopt trans- and cis-orientation, respectively. Complexes 1-5 exhibit moderate NIR phosphorescence with peak maxima located at around 910-930 nm. As supported by the TDDFT approach, the transition mainly involves benzoquinoxaline ³π-[π.sup.*] intraligand charge transfer (ILCT) and metal (Ir) to benzoquinoxaline charge transfer (MLCT) of which the spectroscopy and dynamics of relaxation have been thoroughly investigated. The relatively weak NIR emission can be tentatively rationalized by the low energy gap of which the radiationless deactivation may be governed by nearly temperature-independent, weak-bonding motions in combination with a minor channel incorporating small torsional motions associated with phenyl ring in the benzoquinoxaline sites. Key words: phosphorescence, NIR, iridium, benzoquinoxaline, isoquinoline, bipyridine, pyrazolate, acetylacetonate. On a prepare une nouvelle serie de complexes de l'iridium(III) (1-5) portant des ligands derives de la benzoquinoxaline. L'analyse des donnees structurales du compose 1, obtenues par diffraction des rayons X, revele la presence d'une geometrie octaedrique deformee autour de l'atome d'iridium dans laquelle le chelate pyrazolate se trouve a l'oppose des atomes de carbone donneurs de la benzoquinoxaline orientes en cis, alors que les ligands benzoquinoxaline adoptent une conformation eclipsee et que leurs atomes d'azote coordonnes adoptent respectivement des orientations cis et trans. Les complexes 1-5 presentent de la phosphorescence moderee dans le proche infrarouge (PIR) avec un pic maximal situe autour de 910 a 930 nm. Tel que le predit l'approche TDDFT, la transition implique principalement un transfert de charge interligand (TCIL) ³π-[π*] de la benzoquinoxaline et un transfert de charge du metal (iridium) a la benzoquinoxaline (TCML) dont on a etudie a fond la spectroscopie et la dynamique de relaxation. L'emission relativement faible dans le proche infrarouge pourrait etre rationalisee en fonction d'une discontinuite de faible energie de laquelle la desactivation sans rayonnement pourrait etre orientee par des mouvements de faible liaison, pratiquement independants de la temperature, en combinaison avec une voie mineure qui incorporerait de faibles mouvements de torsion du noyau phenyle dans les sites benzoquinoxalines. Mots cles : phosphorescence, PIR, iridium, benzoquinoxaline, isoquinoleine, bipyridine, pyrazolate, acetylacetonate. [Traduit par la Redaction], Introduction Transition metal complexes, which exhibit strong emission in fluid solution at room temperature, have been extensively investigated owing to their fundamental interest and key roles in the design of [...]

An empirical formula for calculating the extinction cross section (ECS) by raindrops over a broad frequency range is first derived based on extensive calculations made on a widely varying in mean radius of modified Pruppacher and Pitter (MPP) raindrop models ranging from 0.25 to 3.5 mm. The expansion co-efficients in the empirical formula are determined by least-squares curve fitting of numerical data obtained by the volume integral equation formulation (VIEF). The formula satisfies the frequency and raindrop size dependence. Numerical results obtained from the empirical formula for calculating the ECS are generally in good agreement with those calculated by the VIEF for raindrops with mean radius varying from 0.25 to 3.5 mm in the frequency range from 0.6 to 100 GHz. The average error in the ECS is less than 10%. The formula thus provides a simple and inexpensive method for calculating the ECS of raindrops, which otherwise requires complicated and expensive methods of calculation. By implementing this empirical formula of ECS into the rain attenuation equation, a new numerically empirical formula for calculating the specific rain attenuation is also proposed. The validity of the empirical formula for calculating the specific rain attenuation is also checked by comparing the obtained results of specific rain attenuation with those obtained from Li et al.'s solution, Yeo et al.'s measurement, and Oisen et al.'s power-law equation. Index Terms--Extinction cross section, polarization, rain attenuation.

The finite-difference time-domain (FDTD) method is used to analyze the electromagnetic compatibility and interference (EMC and EMI) problems due to the electromagnetic radiation from a video output amplifier located inside a computer monitor. The multiple grid technique is implemented in the FDTD method to improve the computational efficiency. The video output amplifier is modeled by a rectangular iron container with an equivalent dipole antenna located at the center of one opened wall faced to the cathode-ray-tube (CRT). The coupled electric fields inside and outside the monitor are calculated. It is found that higher values of coupled electric fields occur near the monitor screen. It is also found that the coupled electric fields outside the CRT region drop sharply in amplitude. Simulation results of coupled electric fields at a distance of 3 m from the monitor screen also comply with the FCC regulations. Calculation results also agree with the experimental data for coupled electric fields outside the monitor screen at a measured distance of 3 m. Index Terms - Electromagnetic radiation, finite-difference time-domain method, monitor.

The finite-difference time-domain (FDTD) method is used to calculate the specific extinction cross section of the powder of brass 70Cu/30Zn with [10.sup.3] to 2.16 x [10.sup.5] cubical particles for cell sizes in the range of 0.025 to 0.5 [[micro]meter] at infrared frequency. The digitized models with a random process using the turning bands method are simulated for the powder of brass 70Cu/30Zn. From theoretical calculations, the value of specific extinction cross section of the powder of brass 70Cu/30Zn is between 0.1 to 4.6 [m.sup.2]/g. While from the experimental measurement, the value of specific extinction cross section is between 0.58 to 3.78 [m.sup.2]/g. Most of the theoretical results make a good agreement with those obtained from the experimental measurements for the cell sizes of particles in the range of 0.025 to 0.5 [[micro]meter]. From the numerical calculations, it is also found that there is a resonant extinction value occurred at the resonant particle size [d.sub.0] which is approximately [Mathematical Expression Omitted] determined by a least square curve fitting method, where [n.sub.p] is the number of particles. The resonant value calculated by the numerical solution is larger than the maximum value obtained from the experimental measurement.

The finite-difference time-domain (FDTD) method was used to study the nuclear electromagnetic pulse (NEMP) waves coupling into one metallic container through a small aperture in one face of the container. The incident electric fields of NEMP waves were expressed by double exponential forms with two different decay constants. The time-domain behavior of the electric field inside the metallic container excited by the waves was obtained by the FDTD method. The electric field distributions on various layers for the area of the aperture of 10 x 10 [cm.sup.2] were also calculated. It was found thai the shielding effectiveness is greatly improved by a factor of 255 by reducing the area of the aperture from 10 x 10 to 1 x 1 [cm.sup.2]. The aperture filled with dielectric materials was also studied for shielding effectiveness. The coupled electric field inside the metallic container was found to be a nonlinear function of the relative dielectric constant of insulators filled in the aperture.

The near field finite-difference time-domain method was used to calculate the current and specific absorption rate (SAR) distributions in an inhomogeneous model of a human head exposed to the electromagnetic waves irradiated from a cellular phone. The human head was simulated by a model of 57 263 block cells with inhomogeneous dielectric constant and conductivity. The cellular phone was modeled by an equivalent dipole antenna with an equivalent resistor of 120 ohms located at the center gap between the two arms of this dipole antenna. The transmitted power of the cellular phone was assumed to be 0.6 watts at a frequency of 835 MHz. For the head near the dipole antenna in the range of 1.0 [is similar to] 2.5 cm, the maximum currents and SAR's induced in the head were found in the ranges of 356 [is similar to] 551 mA and 1.23 [is similar to] 2.63 W/kg, respectively. It was also found that the maximum SAR induced in the head was below the IEEI's upper safety limit of 1.6 W/kg for the head to keep a distance from the dipole antenna by longer than 2.0 cm.

The validity of the volume integral equation formulation (VIEF) is validated for the purpose of estimating the extinction cross section (ECS) of raindrops. The validations are performed against two well-established models. The validated volume integral equation model is employed to calculate extinction cross sections of raindrops specified by a modified Pruppacher and Pitter (MPP) model. Data are given for drops with mean radii between 0.25 to 3.5 mm in the frequency range 0.6 to 100 GHz. Our study has showed that results of the extinction cross section for vertical and horizontal polarizations can be used to predict rain attenuation in wireless communications. Index Terms--Moment method, polarizations, rain attenuation, wireless communications.