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Cypripedium subtropicum is the only known winter-green species in the genus Cypripedium , whereas the other nearly 50 species keep their leaves for less than half the year. Life form has an important effect on carbon acquisition and adaptation of plants. However, the physiological mechanism behind it remains unclear. In this study, we investigated vegetative anatomy and photosynthetic performance of C. subtropicum across with its leaf ages. These anatomical and photosynthetic traits were also compared with typical Cypripedium spp. and other members of subfamily Cypripedioideae. The obtained results confirmed that this species exhibited many characters of shade plants, such as thin leaves, extremely low photosynthetic rate and light saturation point and high chlorophyll content. Unlike the strategy adopted by typical Cypripedium spp. that quickly achieve annual carbon gain with a high assimilation rate in a short growing season, C. subtropicum obtains its carbon through a low assimilation rate but a much longer leaf lifespan. The local climate and favourable light condition guaranteed the comparable carbon income in winter to compensate for its low photosynthetic capacity. The long-lived, thin leaves of C. subtropicum , differing from the long-lived, thick leathery leaves in conduplicate-leaved genera, represent a distinct adaptive strategy in subfamily Cypripedioideae. Our findings shed light on the divergent and convergent evolution in slipper orchids, and we hope these findings will contribute to the conservation of such an endangered orchid. [ABSTRACT FROM AUTHOR]

The nickel-rich cathodes are always subject to their poor rate performance and cyclic stability. In our paper, a manganese-based oxide layer with oxygen vacancies (MnOx) as a protective coating was proposed to enhance the electrochemical performance of nickel-rich LiNi0.8Co0.1Mn0.1O2 via the sol–gel method. The results demonstrated that MnOx in modified electrode could enable fast ion/charge mobility for superior electrochemical performance. The reversible capacity of MnOx-modified NCM reached 128.2 mAh/g at 5 C, and the cyclic retention of 77.1% was maintained after 200 cycles at 0.5 C. It can be attributed to the MnOx protective layer with oxygen vacancies, which would prevent the side reaction of cathode with electrolytes, maintain the structural stability in long-term cycling and enable the fast ion/charge mobility. [ABSTRACT FROM AUTHOR]

Abstract Introduction Pulmonary ossification has been rarely observed in pulmonary fibrosis and in some chronic respiratory diseases such as chronic obstructive pulmonary disease. We report here a metaplastic ossification in the bronchial cartilage of a patient with multi-drug resistant tuberculosis. Case presentation We report the case of a 41-year-old Asian man from Korea with chronic multi-drug resistant tuberculosis with a rare focus of bone formation from the cartilage of a bronchus subtending an active cavity. The patient had a large multi-lobed, thick-walled cavitary tuberculosis lesion in his left upper lobe. Severe infiltration of his lymphocytes and epithelioid cells, along with some giant cells and neutrophils, was observed in the patient's bronchial wall. Desquamated bronchial epithelium and acid-fast bacilli were found inside his bronchus. A small focus of bony metaplasia was found in the cartilage of his bronchial wall. Histopathological examination confirmed calcification and showed hematopoietic cells forming in his marrow cavity. Conclusions Chronic inflammation in the lungs of our patient, caused by underlying tuberculosis, probably played a role in the development of osseous metaplasia from the associated cartilage of the bronchial wall.

Abstract Background Caspase-independent apoptotic pathways are suggested as a mechanism for the delayed neuronal death following ischemic insult. However, the underlying signalling mechanisms are largely unknown. Recent studies imply the involvement of several mitochondrial proteins, including endonuclease G (EndoG) and Bcl-2/adenovirus E1B 19 kDa-interacting protein (BNIP3), in the pathway of non-neuronal cells. Results In this report, using western blot analysis and immunocytochemistry, we found that EndoG upregulates and translocates from mitochondria to nucleus in a time-dependent manner in cultured hippocampal neurons following oxygen-glucose deprivation (OGD). Moreover, the translocation of EndoG occurs hours before the observable nuclear pyknosis. Importantly, the mitochondrial upregulation of BNIP3 precedes the translocation of EndoG. Forced expression of BNIP3 increases the nuclear translocation of EndoG and neuronal death while knockdown of BNIP3 decreases the OGD-induced nuclear translocation of EndoG and neuronal death. Conclusion These results suggest that BNIP3 and EndoG play important roles in hippocampal neuronal apoptosis following ischemia, and mitochondrial BNIP3 is a signal protein upstream of EndoG that can induce neuronal death.

In order to examine the dynamic mechanical properties, dynamic crack proposition process, and energy loss of fractured rock under dynamic loading, the specimens with different fracture dig angles were processed with Φ50 mm × 50 mm cylindrical sandstone, the impact loading test was conducted on 50 mm stem diameter split Hopkinson pressure bar (SHPB) experiment platform, and the whole process of crack propagation and dynamic failure was recorded using a high-speed camera. As a result, the dynamic mechanical properties such as stress wave fluctuation characteristics, peak strength and stress-strain relationship, crack initiation angle, stress and other dependencies with prefabricated fracture angle of the prefabricated fracture specimens under high strain rate were obtained, and the incident energy, absorbed energy, and energy absorption rates were compared to investigate the energy loss law in the dynamic loading; on the contrary, the effects of different loading rates on the dynamic mechanical properties of the sandstone specimens were identified, and finally a set of findings were presented. [ABSTRACT FROM AUTHOR]

A dense Al2O3 interlayer was inserted into TiN to enhance the tribological and anti-corrosion properties of TiN hard coating via a hybrid process of magnetron sputtering and atomic layer deposition (ALD). The influence of the ALD-Al2O3 layer on the microstructure, mechanical, tribological and anti-corrosion properties of TiN was examined. The TiN-Al2O3 coating exhibits low friction coefficient and specific wear rate, due to the structure change and columnar refinement caused by the addition of amorphous ALD-Al2O3 interlay which improves the mechanical properties of hard coating. The improved corrosion properties of TiN are attributed to the fact that the insulating ALD-Al2O3 used as a sealing layer can prevent the corrosive chlorine ions migrating into the lower TiN layer and block the charge transport in coatings. Moreover, raising the insertion position of ALD-Al2O3 layer away from the steel substrate results in a further increase in the anti-corrosion property of TiN-Al2O3 composite coating. [ABSTRACT FROM AUTHOR]