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Vegetation phenology is an important indicator of environmental change and strongly connected to forest ecosystem productivity change. This study aimed to analyse the pattern of phenological variations derived from digital imagery for the interpretation of ecosystem productivity. For 2014, 2015 and 2016, the seasonal phenological development of savanna was analysed by using towerbased imagery from a digital camera. The green excess index (GEI) was the best at representing the phenological transition dates (PTDs) and useful for investigating the gross primary production (GPP) in the savanna ecosystem. There was a significant correlation between the monthly pattern of the strength of green (Sgreen), green excess index (GEI) and vegetation contrast index (VCI) and GPP throughout the year. Additionally, the annual pattern of colour indices had significant relationship (p < 0.05) with GPP but this was not seasonal. The air temperature (air T) and soil temperature (soil T) were strongly significantly correlated (p < 0.001) with the start of growing season (SGS) and caused the advance in green-up and the timing of the start of the growing season in 2014 and 2016. The short growing season length (GSL) had an impact on the productivity. The colour indices from the digital camera images not only provided the phenological pattern of a forest canopy but also revealed the forest ecosystem productivity by showing the response to environmental factors. Our results indicate that daily continuous digital camera images might be useful for ecologists to use as a tool for future prediction of the long-term phenological modelling. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To explore the regulatory mechanism of micro-ribonucleic acid (miR)-122-3p in the osteogenic differentiation of mouse adipose-derived stem cells (mADSCs). MATERIALS AND METHODS: The regulatory mechanism of miR-122-3p in the osteogenic differentiation of mesenchymal stem cells was investigated through its overexpression and knockdown. RESULTS: The overexpression of miR-122-3p inhibited the osteogenic differentiation of mADSCs. On the contrary, its knockdown promoted the osteogenic differentiation of mADSCs. The further study on the molecular mechanism of miR-122-3p regulating mADSCs' osteogenic differentiation showed that the overexpression of miR-122-3p could activate the Wingless and int-1 (WNT)/β-catenin signaling pathway, but the knockdown of miR-122-3p could repress this signaling pathway. CONCLUSIONS: MiR-122-3p influences the osteogenic differentiation of mADSCs by modulating the WNT/β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The purpose of this study was to explore the mechanism of micro-ribonucleic acid (miR)-214-3p in regulating fracture healing in rats with osteoporosis. MATERIALS AND METHODS: A total of 30 female Sprague-Dawley rats were selected and randomly divided into 3 groups, including group A [phosphate-buffered saline (PBS), n=10], group B (AntagomiR-NC, n=10), and group C (AntagomiR- 214-3p, n=10). All rats underwent ovariectomy, and the osteoporosis rat model was verified by dual-energy X-ray absorptiometry 8 weeks after the operation. Then the osteoporotic fracture was established in rats via a second operation. From the successful modeling until the 6th week, 50 μL PBS (2 nmoL) was intraperitoneally injected in group A, an equal amount of AntagomiR-NC was injected in group B, and an equal amount of AntagomiR-214-3p was injected in group C once a week. At the 6th week, fracture healing of osteoporosis rats was evaluated. At the same time, the expression of miR-214-3p in the three groups was detected via reverse Transcription-Polymerase Chain Reaction (RT-PCR). Furthermore, the protein expressions of bone morphogenetic protein 2 (BMP2) and Smad4 in the three groups were detected via Western blotting (WB). RESULTS: After ovariectomy, the bone mineral density in each group was significantly lower than that before ovariectomy, and the differences were statistically significant (p<0.05). Imaging evaluation demonstrated that compared with group A and B, there were significantly more callus tissues in group C. Meanwhile, the fracture line healing was better and blurred, and the internal fixation had no displacement and loosening. RT-PCR results indicated that the expression level of miR-214-3p in group C was significantly lower than that of the other two groups (p<0.05). WB results showed that the protein expression levels of BMP2 and Smad4 in group C were significantly higher than those of group A and group B (p<0.05). CONCLUSIONS: MiR-214-3p delays fracture healing in rats with osteoporotic fracture by inhibiting the BMP/Smad signaling pathway. [ABSTRACT FROM AUTHOR]

This letter reports a mechanism of chemistry-mediated two-dimensional to three-dimensional (2D-3D) transition during In thin film deposition, and the corresponding evolution of nanoscale islands. Using magnetron sputtering technique, we deposit In on Au substrate. Despite the fact that In wets on Au, In islands prevail over the uniform film soon after the deposition starts. The 2D-3D transition is found to be a result of the formation of Au3In on the Au substrate. The alloy formation leads to nonwetting of In, thereby the high mobility of In atoms and In clusters, and eventually well-separated In islands. The structures of In and Au are characterized by scanning electron microscopy, transmission electron microscopy, and electron diffraction. [ABSTRACT FROM AUTHOR]

Southeast Madagascar hosts several major deposits of beach placers, the provenance of which is little understood. To redress this imbalance, we present new laser ablation-- inductively coupled plasma--mass spectrometry (LA-ICP-MS) U-Pb ages, and trace elements of zircons and monazites, as well as Hf isotopes of zircons from heavy mineral beach sands at Taolagnaro (Fort Dauphin) in SE Madagascar. The ages of detrital zircon grains range from 650 Ma to 450 Ma and from 1900 Ma to 1700 Ma (one grain has an age of 2633 Ma), and detrital monazite ages range from 574 Ma to 484 Ma. The Ediacaran--Cambrian zircons (650-450 Ma) and monazites (574-484 Ma) record a major Pan-African orogenic event in SE Madagascar. Geologically, the 650-450 Ma ages correlate well with coeval granitic gneisses in southern Madagascar, and a few 1900-1700 Ma ages can be linked to putative Paleoproterozoic protoliths of metasedimentary rocks from the Anosyen Domain and from the Itremo Group of central Madagascar. The zircon mineral chemistry indicates that some of the grains (P > 25 μmol g-1) were sourced from S-type granitic rocks. The monazite chemistry points toward a metamorphic provenance from garnet-bearing amphibolite facies rocks, such as migmatitic gneisses in southern Madagascar. The Hf isotopic compositions of detrital zircons indicate reworking of their probable Paleoproterozoic--Archean source rocks. We conclude that the beach sand zircons and monazites were largely sourced from the uplifted and eroded Anosyen and Androyan Domains in SE Madagascar, and with minor contributions from central Madagascar, which were all transported by rivers to the ambient ocean to the southeast. [ABSTRACT FROM AUTHOR]

Background: We studied the change of brain tissue oxygen pressure (PbrO2) value within 24 hours after trauma and during moderate hypothermia in patients with severe head injury. The PbrO2 value was used to differentiate patients at risk of brain ischemia and to predict outcome., Methods: A flexible microcatheter to be used for continuous monitoring of brain tissue oxygen was inserted into the normal frontal white matter, along with a thermocouple, in 14 patients with severe head injury within 1.5-12 hours (mean 6.1 +/- 5.2 hours) after trauma. Moderate hypothermia was also used within 24 hours in these patients., Results: (1) No complications related to the microcatheter were seen. (2) Low initial PbrO2 values (mean values <10 mmHg) were noted after severe head injury. (3) The occurrence of low initial PbrO2 values (< or = 5 mmHg) was significantly correlated with a poor outcome. (4) Moderate hypothermia can increase PbrO2, but hyperventilation reduced PbrO2. (5) The difference between RT and BT increased during moderate hypothermia., Conclusions: The PbrO2 values were low in severe head injury, but hypothermia may improve these values. The technique of continuously monitoring brain tissue oxygen pressure may give better insight into cerebral oxygenation and warn of impending ischemia of brain tissue, especially in patients treated with hyperventilation. It will help to improve the management and final outcome of patients with severe head injuries.

Five main saponins were separated from the cell cultures of Panax notoginseng (Burk) F. H. Chen. They were sanchinoside Rb1, Re, R1, Rg1 and Rh1 identified by TLC, HPLC, IR, M. P., 13CNMR and EI-MS. Saponin components of the cell cultures were almost the same as those of the cultivated plants. But the content of saponins was different between the cell cultures and the cultivated plants. Saponin extraction and separation procedure suitable for the cell cultures has to be different from that for the cultivated plants.

By omitting the component NH4NO3 and doubling the amount of KNO3 in MS medium, the Panax quinque folium cells cultured in such medium grew more rapidly and their saponin content was much higher than that cultured in regular MS medium. The growth rate and saponin content of the cells cultured in such medium (KNO33300 mg/l) increased 65.1% and 166.2% respectively as compared with that cultured in the regular medium. The application of oligosaccharins from Panax ginseng and Dendrobium candidum also increased their saponin content and growth rate. Especially, the content of Rg group saponins was apparently raised. It took more than 25 days for the cell suspension cultures to produce saponins in large amounts. The curve of saponin formation lagged slightly behind the growth curve in cell suspension culture and fermentation culture. The cell fermentation culture with a stabilized pH value was better than the culture with the pH value changing spontaneously on saponin content, growth rate and biomass. Finally, the culture patterns of P. quinque folium cells were compared and discussed.