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Alumina ceramics used in microwave systems are susceptible to the multiplication of secondary electron emission on the surface due to the influence of resonation between electrons and RF electrical field, and the detrimental effect of multipactor may be therefore triggered. For the alumina-loaded microwave components, low secondary electron yield (SEY) is urgent to be achieved on the inserted alumina surfaces for mitigating multipactor. In this work, for achieving an ultralow SEY surface of alumina, two recognized low-SEY treatments are combined. For the primary SEY suppression, a series of microstructures were fabricated on the alumina surfaces with various porosity and aspect ratio at hundred-micron scales by infrared laser etching. The microstructure with 52.14% porosity and 1.78 aspect ratio showed an excellent low-SEY property, which could suppress the SEY peak value (δm) of alumina from 2.46 to 1.00. For the secondary SEY suppression, the SEY dependence of TiN coating on sputtering parameters was studied, and the lowest δm of 1.19 was achieved when the gas flow ratio of Ar:N2 was 15:7.5. Whereafter, by depositing TiN ceramic coating onto the laser-etched porous samples, an ultralow SEY, δm equaled 0.69, was achieved on the alumina surfaces. The simulation work revealed the impact of dielectric surface charge on electron multiplication and uncovered the mechanism of using low SEY surfaces to inhibit multipactor. Some coaxial filters with alumina filled were fabricated for verification, the results revealed that the multipactor threshold increased from 125 W to 425 W after applying the TiN-coated porous alumina, and to 650 W after treating another multipactor sensitive area with the same low-SEY process. This work developed an advisable method to sharply reduce SEY, which is of great significance for the multipactor mitigation of the alumina-loaded microwave components.

A trispecific hybrid, MTP (hereafter called tripsazea), was developed from intergeneric crosses involving tetraploid Zea mays (2n = 4x = 40, genome: MMMM), tetraploid Tripsacum dactyloides (2n = 4x = 72, TTTT), and tetraploid Z. perennis (2n = 4x = 40, PPPP). On crossing maize-Tripsacum (2n = 4x = 56, MMTT) with Z. perennis, 37 progenies with varying chromosome numbers (36-74) were obtained, and a special one (i.e., tripsazea) possessing 2n = 74 chromosomes was generated. Tripsazea is perennial and expresses phenotypic characteristics affected by its progenitor parent. Flow cytometry analysis of tripsazea and its parents showed that tripsazea underwent DNA sequence elimination during allohexaploidization. Of all the chromosomes in diakinesis I, 18.42% participated in heterogenetic pairing, including 16.43% between the M- and P-genomes, 1.59% between the M- and T-genomes, and 0.39% in T- and P-genome pairing. Tripsazea is male sterile and partly female fertile. In comparison with previously synthesized trihybrids containing maize, Tripsacum and teosinte, tripsazea has a higher chromosome number, higher seed setting rate, and vegetative propagation ability of stand and stem. However, few trihybrids possess these valuable traits at the same time. The potential of tripsazea is discussed with respect to the deployment of the genetic bridge for maize improvement and forage breeding.

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Background Although men and women are equally likely to carry a mutation in the BRCA1 and BRCA2 (BRCA) genes, the clinical significance of mutations in men remains incompletely defined. We sought evaluate interest of individuals from BRCA families to participate in a research study focused on men from BRCA families. Methods Through an anonymous survey posted on the website of the BRCA patient advocacy organization, Facing Our Risk of Cancer Empowered (FORCE), data was collected over a 21 month period (August 2010–June 2012) from members of BRCA families. Results The survey was completed by 405 individuals with known BRCA mutations, including 150 males and 232 females. The median age of survey respondents was 49 years (50 years for males and 48 years for females). Overall, 84% of survey respondents indicated prior BRCA mutation testing (95.2% females, 67.3% males). For the overall group of survey respondents, 84% (86% females, 84% males) indicated they would tell their male relatives about a research study focused on high risk men from BRCA families, and 53% (39% females, 74% males) thought that their male relatives would be interested in participating in such a study. Conclusion Despite limited studies focused on men from BRCA mutation positive families, our survey suggests that both male and female family members are highly interested in focused on male BRCA mutation carriers. The importance of further studying this topic is underscored by emerging literature that suggest cancer surveillance and treatment decisions may improve outcomes in men with BRCA mutations.

In our study, we developed a system to reduce both energy consumption and pollutant discharge during the drying process. We present a new technology, a stationary bed grain-drying test device based on the internal circulation of the drying medium (ICODM). A rice-drying experiment was carried out inside of it, and the influences of air temperature (AT) and air velocity (AV) on the energy and exergy efficiencies (EEE) as well as the improvement potential rate (IPR) and the sustainability index (SI) of the rice-drying process were studied. The following conclusions were obtained: when the rice was dried at a temperature of below 55 °C and an AV across the grain layer of 0.5 m/s, the average EEE during the drying process was 48.27–72.17% and 40.27–71.07%, respectively, demonstrating an increasing trend as the drying medium temperature increased. When the rice was dried using an AV across the grain layer in the range of 0.33–0.5 m/s and a temperature of 40 °C, the two values were 39.79–73.9% and 49.66–71.04%, respectively, demonstrating a decreasing trend as the drying medium flow velocity increased. IPR and SI were 4.1–8.5 J/s and 1.9–2.7, respectively, at a drying temperature of 30–55 °C and an AV of 0.33–0.5 m/s. These conclusions can provide helpful guidance for the optimization and control of the rice-drying process in terms of saving energy.

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