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Helmholtz resonator (HR) is widely used in various fields, but the classic HR usually should satisfy the acoustically compact condition, which limits the application range of the classic HR. This paper investigates analytically and numerically the acoustic performance of a HR in which the length of the neck is not limited under the acoustically compact conditions. An analytical model is developed for accurately and quickly predicting resonant frequencies and transmission loss of the Helmholtz resonator with an extended neck (HREN), and numerical simulations have been performed to validate the developed analytical model. Both the analytical and numerical studies reveal that the HREN has multiple resonant frequencies, and a method is developed for approximate and fast calculation of the multiple resonant frequencies. [ABSTRACT FROM AUTHOR]

ARTICLE INFO Keywords: Monochasma savatieri Franch Phenylethanoid glycosides Myocardial ischemia Antioxidant Cardiac oxidative injury ABSTRACT The present study was designed to investigate the cardioprotective effect of total phenylethanoid glycosides from [...]

1,25(OH) 2 D 3 has been demonstrated to exert direct actions on male reproductive system in humans or in animals. With age, renal synthesis of 1,25(OH) 2 D 3 declines significantly, and vitamin D supplementation has been found to alleviate the manifestations of male reproductive aging. Therefore, the relationship between 1,25(OH) 2 D 3 and male reproductive aging needs further study. To determine whether 1,25(OH) 2 D 3 deficiency accelerates male reproductive senescence in aging mice, wild-type and 1α(OH)ase -/- male mice fed a rescue diet after weaning, and the reproductive phenotypes were evaluated at 12-18 mo of age. We demonstrated that 1,25(OH) 2 D 3 deficiency accelerated male reproductive senescence, representing lower fertility efficiency and gonadal hormone levels, reducing cell proliferation, and increasing cell apoptosis, cellular senescence, and the senescence-associated secretory phenotype (SASP). We confirmed that the increased oxidative stress and DNA damage detected in 1α(OH)ase -/- mice resulted in accelerated reproductive senescence in reproductive system, since exogenous antioxidant pyrroloquinoline quinone (PQQ) supplementation could largely rescue reproductive aging phenotype. We further validated the antioxidant effect of 1,25(OH) 2 D 3 in aging wild-type mice and senescent Leydig cells by treated 18-mo-old wild-type male mice or TM3 cells with 1,25(OH) 2 D 3 or vehicle. We assessed the differential gene expression between grouped senescent TM3 cells using RNA-Seq and verified 1,25(OH) 2 D 3 exerted an antioxidant role by acting NF-κB/SOD. This study suggests that 1,25(OH) 2 D 3 deficiency accelerates male reproductive senescence in aging mice by increasing oxidative stress and 1,25(OH) 2 D 3 plays a role in alleviating oxidative stress via NF-κB/SOD signaling pathway. NEW & NOTEWORTHY Based on this studies, we propose that 1,25(OH) 2 D 3 can delay male reproductive aging, and we also propose that 1,25(OH) 2 D 3 regulates NF-κB to exert antioxidant effect. Therefore, by targeting a fundamental aging mechanism, 1,25(OH) 2 D 3 may be an effective agent in maintaining fertility and postponing male reproductive senescence.

The present study was designed to investigate the cardioprotective effect of total phenylethanoid glycosides from Monochasma savatieri Franch (TPG). The data showed that there were mainly four phenylethanoid glycosides isolated and identified from TPG. TPG significantly increased cells viability and inhibited morphological changes on H9c2 cardiomyocytes induced by H2O2 or Na2S2O4. In addition, TPG significantly decreased T-wave elevation and histopathological changes of heart tissues in myocardial infracted rats induced by isoproterenol. It also significantly reduced the infarct size induced by ligating the coronary artery in rats, increased the activities of antioxidative enzymes superoxide dismutase (SOD), the content of glutathione (GSH), and decreased the leakage of lactic dehydrogenase (LDH), the activities of creatine kinase (CK) and the content of maleic dialdehyde (MDA). In conclusion, these results suggested that TPG from Monochasma savatieri Franch might be developed as new natural medicine or food additives with effects of prevention of coronary artery disease due to its significant antioxidant activity., (Copyright © 2013 Elsevier GmbH. All rights reserved.)