Maca has been reported to alleviate male menopause symptoms in humans and experimental animals; however, its mechanism of action in improving male menopause has not been clearly identified. This study aimed to investigate the mechanism of action of gelatinized maca in improving male menopause by analyzing serum testosterone, testicular androgen receptor (AR) expression, and testicular oxidation-antioxidation balance. Gelatinized maca was administered orally to aged male C57BL/6 mice at three doses (500, 1,000, and 1,500 mg/kg/day) for 28 consecutive days. Serum biochemical analysis showed an increase in serum hydroxysteroid 17-beta-dehydrogenase 13 (HSD17β13) concentration at 1,500 mg/kg/day and a decrease in serum sex hormone-binding globulin (SHBG) concentration at ≥ 1,000 mg/kg/day. Gelatinized maca administration also resulted in the increased expression levels of testicular AR and cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) at 1,500 mg/kg/day. Oxidative stress analysis showed an increase in testicular superoxide dismutase and glutathione reductase activities and a decrease in testicular malondialdehyde at 1,500 mg/kg/day. In conclusion, gelatinized maca administration to aged male mice increased HSD17β13, AR and CREB expression, and antioxidant capacity and decreased serum SHBG. The results of the present study suggest that gelatinized maca may be a useful substance that can help alleviate male menopause symptoms.

항암작용과 간 질환을 예방하는 약용곤충으로 널리 알려진 흰점박이꽃무지 유충은 2016년 12월 일반식품으로 등록되었으나 판매가가 높아 소비가 활발하게 이루어지지 않고 있어 생산 단가를 낮추는 기술이 요구되고 있는 실정이다. 흰점박이꽃무지의 생산 비용을 절감하고 생산성을 향상시키기 위해 농업부산물인 새송이버섯 수확 후 배지와 표고버섯 수확 후 배지를 유충의 먹이로 급이하여 생육특성과 미량성분, 중금속함 량을 조사하였고 대조구로는 관행으로 사용되고 있는 참나무 발효톱밥을 급이하였다. 새송이버섯 수확 후 배지를 급이한 처리구가 유충사육기간이 16.2일로 가장 짧았고 유충 무게 증가율과 고치 무게는 각각 156.3%와 4.1 g이었다. 새송이버섯 수확 후 배지를 급이한 처리구에서 용화율은 100%였고 우화율은 93.9%로 가장 높았지만 통계적 유의차는 없었다. 또한 총질소함량도 10.28%로 가장 높았고 미량원소 중 철은 145.8 mg/kg으로 다른 먹이와 비교해 높은 결과를 보였다. 성충의 산란선호성은 먹이 간 통계적 유의차가 없었다. 본 연구의 결과를 종합하였을 때 기존에 사용하고 있는 참나무 발효톱밥 대신 새송이버섯 수확 후 배지를 먹이로 사용하면 흰점박이꽃무지 유충 100 kg 당 667,960원의 비용이 감소할 것으로 추정된다.

Insect pollinators of the endanger orchid Cypripedium japonicum were surveyed and identified during two years, as a part of a conservation project of the orchid at Jukyeup-san and Hwaak-san (Mt.), South Korea. In total 40 individuals of 16 species in 4 families were identified. The dominant family was Halictidae, and Lasioglossum exiliceps Vachal visited the most frequently C. japonicum during the surveys. The average visiting frequency was 2.5 individuals per hour and the highest 4.3, from 12:00 – 13:00 in a day. After 15:00 insects did not visit the flowers at all. However, all of the visiting insects were found to not carry a pollinium or pollens of the orchard on their bodies; pollen carryover by any of the visiting insects did not occur at all. The orchid seems to require certain pollinators in particular body thickness due to its unique pollination mechanism. The orchid has two exit route openings, around 1 cm in diametre, where the entrapped insects can exit and an anther is situated just in front of each opening. It was inferred that a pollen carrier should be around 1 cm in body thickness. Therefore, the candidate species as the proper pollen carriers can be Tetralonia nipponensis Perez, Xylocopa appendiculata circumvolans Smith and Bombus consobrinus Dahlbom among the surveyed visitors.

Numerical simulation has been carried out to analyze seawater flow characteristics for shroud geometry variations with tidal current generation turbine. Seawater flow field characteristics in the turbine system are largely influenced by the shroud geometry. The vortex flow area in the diffuser part of the shroud gradually grows with the increase of shroud angle, but its recirculation velocity gets smaller. The centerline velocity of shroud increases with the length of cylinder part when diffuser part length and angle are constant(2.5m, 0.733rad) for the cylinder-diffuser type shroud system. Seawater velocity on the tip of turbine blade is pretty high, and as radial distance increases from the turbine axis, there is more gap between the fluid velocity isolines. These results in this study will be applicable for optimal design of tidal current generation system.

흡연 유무의 남성을 대상으로 뇌 회백질의 손상 유무를 파악 할 수 있는 확산텐서영상을 검사하여 영상을 획득 한 후 Tract-Based Spatial Statics(TBSS)방법으로 뇌 회백질 부위의 기저핵 신경섬유로의 비등방도 FA(fractional anisotropy)값을 측정 분석한 결과 모든 영역에서 흡연자가 비흡연자보다 비등방성 측정값이 낮게 관찰되었으며 FA값은 통계적으로 유의하였다. 본 연구의 측정한 FA결과 값으로 추측하자면 즉, 흡연이 뇌 회백질 기저핵의 모든 해부학적 미세 구조성 변화에 크게 영향을 미치며 신경 섬유로를 손상시키고 이와 관련된 기능적 이상에 영향을 준다고 할 수 있다.

We investigated the effects of temperature changes on the oxygen consumption rhythm in Japanese eels, Anguilla japonica, using an automatic intermittent flow respirometer (AIFR). The endogenous rhythm of the oxygen consumption rate (OCR) in the eels (n = 18; 44-74 cm, 145-690 g), freshly collected by bag net from estuaries, was nearly synchronous with the tidal pattern of the estuarine collection site. The magnitude of mean OCR (mOCR) of eels showed variable range of 82.2 - 116.5 ml O2 kg-1 ww h-1 under constant conditions. In case of increasing temperature from 25 to 38℃, the OCR of eels exhibited a gradually increasing trend with a rhythmic pattern until 36℃. Above 36℃, the rhythms of the OCR dampened and the OCR decreased rapidly at around 36 - 37℃. The OCR of the eels exhibited the maximum value at 38℃, and then it sharply decreased. The results suggested that the critical thermal maximum (CTM) regarding the endogenous rhythms of the eels was at around 36 - 37℃ when water temperature increased at 0.5℃/14 h following the acclimation at 25℃. In case of decreasing temperature (0.5℃/14 h) from 25 to 0℃, the OCR of the eels displayed a abrupt decrease up to 23℃, and between at 23 and 20℃, there was an agitation which showed a slight increase in the OCR with a duration of 1-2 days. Below 9℃, the OCR rhythm of the eels showed a constant state regardless of temperature decreasing. These results suggest that the Japanese eel has an upper incipient lethal temperature at 36℃, with a lower thermal limit at 9℃. The biochemical aspects of the eels influenced by water temperature need to be further studied.