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Bahe river is the secondary tributary of the Yarlung Zangbo river, and the largest tributary of Nyang River in China, for which we analyzed the microbial diversity, community structure and metabolic function diversity in the surface sediments of 3 cascade hydropower stations upstream and downstream and their adjacent tributaries were analyzed by high-throughput sequencing. The study has shown that the abundance of microbial community in the surface sediments of Bahe cascade hydropower station were as follows S7(downstream of Laozui Hydropower Station), S3(downstream of 606 Hydropower Station), S5(Zhulaqu of Bahe tributary), S4(upstream of Xueka Hydropower Station), S1(upstream of 606 Hydropower Station), S2 (Zimuzhongnongbaqu of Bahe tributary) and S6(downstream of Xueka Hydropower Station/upstream of Laozui Hydropower Station), and the microbial diversity and abundance of 7 sampling points were lower than those of other areas. The predominant bacteria in the surface sediments of Bahe cascade hydropower stations are Proteobacteria, Cyanobacteria, Frimicutes, Actinobacteria, Bacteroides, etc. The dominant bacteria are Exiguobacterium, Tychonema_CCAP_1459-11B, norank_f__unclassified_o__Oxypotobacteria_Incertae_Sedis, Hyphobacterium, Sphingorhabdus, Leptolyngbya_FYG, Phytobacter, Pseudoarthrobacter, Pseudoarthrobacter, Unclassified_f__ Microbacteriaceae. Predominant bacteria varied significantly between samples. Further study shown that total phosphorus, temperature and flow velocity were the main factors affecting microbial community structure in plateau rivers. And the cascade effect also affects the microbial community structure, the functional genes, functional proteins, dominant enzymes and FAPROTAX functions of the river in S3 and S4. However, cascade effect was failure in S6, S7. [ABSTRACT FROM AUTHOR]

The Nyang River is located in an area sensitive to global climate change, the climate warming changes and human activities have impacted the fragile ecosystem of Plateau Rivers, for which we analyzed the bacterial diversity, community structure characteristics and main influencing factors in the surface sediments of 7 sampling sites in the middle and lower of the Nyang River in Tibet which is in China by high-throughput sequencing technology. The study showed that the abundance of bacterial community in the surface sediments of the middle and lower reaches of the Nyang River that is S1 (upstream of the junction of Bahe Town), S2 (Bahe River), S3 (downstream of the junction of Bahe Town), S4 (upstream of Duobu Hydropower Station), S5 (downstream of Duobu Hydropower Station), S6 (upstream of Bayi Town), S7 (downstream of Bayi Town). The abundance of bacterial community and bacterial diversity at S2 site are relatively high, and the bacterial diversity and abundance of the 7 sampling sites are lower than those of other areas. Five dominant bacteria phyla, including Firmicutes, Proteobacteria, Cyanobacteria, Actinobacteria, Bacteroidetes, and seven dominant bacteria genera, including Exiguobacterium, Hymenobacter, Hyphomicrobium, Leptolyngbya_FYG, Phormidesmis_ANT. L52.6, Tychonema_CCAP_1459-11B were extracted from the surface sediments of the middle and lower reaches of the Nyang River in the dry season. There were significant differences in the dominant bacteria among the samples. Further study found that the influencing factors were flow velocity, environmental factors and nutrients in descending order. [ABSTRACT FROM AUTHOR]

A discussion of 7.5 mol% Nb: KTP crystals and KNbO3 crystals is presented, focusing on generating blue coherent light. Topics include Sellmeier's equation for 7.5 mol% Nb:KTP crystals, and second-harmonic generation calculations.

OBJECTIVE: Metastatic lung cancer often spreads to the musculoskeletal structures and spinal column. Patients suffering from spinal metastasis due to lung cancer present poorer prognostic outcomes in terms of overall survival compared to spinal metastases from other origins. To date, no meta-analysis has attempted to evaluate the prognostic impact of various predictive factors that may influence the overall survival of patients with spinal metastasis due to metastatic lung cancer. The aim of the study was to evaluate the prognostic impact of different predictive factors that might influence the overall survival of patients with spinal metastasis due to metastatic lung cancer. MATERIALS AND METHODS: Five electronic databases (Web of Science, EMBASE, CENTRAL, Scopus, and MEDLINE) were screened for eligible studies according to PRISMA guidelines. We conducted a random-effects meta-analysis to evaluate the prognostic impact of aging, pre-ambulatory status, radiotherapy, adenocarcinoma, performance status, visceral metastasis, and number of affected vertebrae on the overall survival of patients with spinal metastasis due to lung cancer. RESULTS: From 963 studies, we found 13 eligible studies with data on 1144 patients. Our meta-analysis revealed that pre-treatment ambulatory status (2.08), Eastern cooperative oncology group score (1.78), and aging (1.68) had significant impacts on overall survival. CONCLUSIONS: We provide preliminary evidence highlighting three factors potentially predictive of overall survival for patients suffering from spinal metastasis due to metastatic lung cancer. These findings may help clinicians stratify and manage patients more effectively. [ABSTRACT FROM AUTHOR]

A physical model is developed with the volume of fluid (VOF) method to track the free interface in the meltpool to understand the meltpool evolution, fluid flowing and the behaviour in gas and liquid interface. The model is characterized with a combined heat source model consisting of a parabolic rotating and a cylindrical distribution, and a stochastic distributed model of powder bed with powder particle size. The heat source is only loaded in the unit interface between metallic and gas phase in the laser-powder interaction zone. The simulation is carried out only in first and second laser scanning track due to the reduction in computing time. Simulation results exhibits the fluid flowing and surface morphology in the meltpool is determined significantly by different laser parameters such as laser power and scanning velocity. The simulated meltpool geometry has good agreement with the experimental ones. The meltpool geometry of the first track changes from the approximate circle, ellipse to 'comet' due to the heat accumulation during continuous laser scanning. The meltpool geometry of the second track becomes much larger, its temperature is higher and the fluid flowing is faster than that of the first track. The melt metal flows violently in the initial position due to the high flowing velocity in a limit melt space. The second track has enough space for metal flowing and it is easy to obtain a smooth surface morphology than the first track; thus, a long enough meltpool helps to get a steady fluid and smooth surface morphology. The temperature of the meltpool at beam centre fluctuates during laser scanning process, which depend on the determined effects of the interaction between thermal conduction and violent fluid flowing or the interaction between heat accumulation and violent fluid flowing. The information about temperature distribution and fluid flowing in the meltpool provided by the simulation helps to analyse and understand the formation mechanism of the meltpool geometry, surface morphology and meltpool evolution as well, benefiting to further control the laser powder bed fusion (LPBF) processing of Ti6Al4V alloy powder. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The purpose of this study was to conduct a systematic review and meta-analysis analyzing the efficacy of zoledronic acid in improving outcomes with percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) surgeries for osteoporotic vertebral compression fracture (OVCF). MATERIALS AND METHODS: We electronically searched the databases of PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar up to 15th September 2020. All types of studies assessing the use of zoledronic acid with PKP/PVP surgeries were included. RESULTS: Seven studies were included. On meta-analysis of data from five studies reporting bone mineral density (BMD) as g/cm², we found a statistically significant increase in BMD in the zoledronic group (MD: 0.14; 95% CI: 0.07, 0.21, I²=97%; p<0.001). On pooled analysis of two studies reporting T scores, a similar result in favour of the zoledronic acid group was noted (MD: 0.60; 95% CI: 0.23, 0.98, I²=76%; p=0.002). We also found a statistically significant reduction in pain scores (MD: -1.23; 95% CI: -1.59, -0.86, I²=97%; p<0.00001), ODI scores (MD: -9.54; 95% CI: -12.76, -6.31, I²=95%; p<0.00001) and serum type I procollagen peptide (CTX) levels (MD: -0.19; 95% CI: -0.25, -0.12, I²=98%; p<0.00001) with zoledronic acid as compared to control. Our analysis also found a significantly reduced risk of further vertebral fractures in patients receiving zoledronic acid as compared to control (RR: 0.17; 95% CI: 0.07, 0.39, I²=0%; p<0.00001). CONCLUSIONS: Our review indicates that the use of once-yearly zoledronic acid in the peri-operative period of PVP/PKP procedures for patients with OVCF leads to significant improvement of BMD, reduced pain scores, better ODI scores, and reduced incidence of further vertebral fractures. Our results have clinical significance as it encourages the use of zoledronic acid for such patients for better clinical outcomes. [ABSTRACT FROM AUTHOR]