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Background: Increased leisure-time physical activity (LTPA) is linked with decreased mortality risk, while also with increased left ventricular mass, which may induce left ventricular hypertrophy (LVH). We investigated whether LVH modifies the association between higher LTPA and lower mortality risk in population at high cardiovascular risk. Methods: In a prospective national cohort, we used the left ventricular mass/body surface area (LVM/BSA) method to define LVH. Baseline LTPA was self-reported and divided into: low (<500 metabolic equivalent of task [MET]) min/week), moderate (500–1999 MET min/week) and high (≥2000 MET-min/week). Analyses of the dose-response relationship between LTPA and left ventricular mass were performed using restricted cubic spline regression. A multivariate adjusted Cox proportional hazards regression analysis was used to estimate hazard ratios (HRs). Results: A total of 163,006 participants (55.3% females, mean [standard deviation] age, 62.4 [7.4] years) were included. During a median of 4.8 years of follow-up, 6586 (4.0%) died from all causes and 3024 (1.9%) from cardiovascular causes. Multivariate adjusted Cox proportional hazards regression analyses revealed that moderate and high LTPA were linked with less cardiovascular and all-cause mortality risk than low LTPA in the absence of LVH. In those with LVH, the association of high (0.83, 0.69–0.99) or moderate (0.72, 0.56–0.91) LTPA with cardiovascular mortality risk persisted. For all-cause mortality risk, this association was only significant in high LTPA (0.73, 0.61–0.86), while marginal in moderate LTPA (0.96, 0.84 to 1.08). Overall, the correlation patterns between LTPA and mortality risk appears distinct between those with LVH and those without LVH; the modification of LVH was not significant regarding mortality risk among the high cardiovascular risk population (all-cause: p-value for interaction = 0.074; cardiovascular cause: p-value for interaction = 0.581), except in females regarding all-cause mortality risk (p-value for interaction = 0.006). Conclusions: The association between higher LTPA and lower mortality risk was not modified by LVH in high cardiovascular risk population. However, the presence of LVH altered this association in females regarding the all-cause mortality risk. [ABSTRACT FROM AUTHOR]

Ground surface temperature (GST), measured at approximately 5 cm in depth is a key parameter controlling subsurface biophysical processes at the land-atmosphere boundary. This work presents a valuable dataset of GST observations at various spatial scales in the Headwater Area of the Yellow River (HAYR). The HAYR is a representative area of high plateau permafrost on northeastern Qinghai-Tibet Plateau (QTP). GST was measured every three hours using 72 iButton temperature loggers (DS1922L) at 39 sites from 2019 to 2020. At each site, GST was recorded in two plots at distances from 2 to 16 m under similar and different landcover conditions (steppe, meadow, swamp meadow, and bare ground). These sensors proved their reliability in harsh environments as only 165 measurements were biased from a total of 210,816. A high significant correlation (> 0.96, p < 0.001) was observed between plots, with a mean absolute error (MAE) of 0.2 to 1.2 °C. The daily intra-plot differences in GST were mainly < 2 °C for sites with similar landcover in both plots and > 2 °C when bare ground was compared to vegetation. From autumn to spring, the differences can increase to 4-5 °C for up to 15 days. The values of the frost number (FN) were quite similar between the plots with differences < 0.05 for most of the sites. This dataset complements the sparse observations of GST on the QTP and helps to identify the permafrost distribution and degradation at high resolution and to validate and calibrate the regional permafrost models. The datasets are openly available in the National Tibetan Plateau/Third Pole Environment Data Center (https://dx.doi.org/10.11888/Cryos.tpdc.272945, Șerban and Jin, 2022). [ABSTRACT FROM AUTHOR]

Database systems usually have many parameters that must be configured by database administrators and users. RocksDB achieves fast data writing performance using a log-structured merged tree. This database has many parameters associated with write and space amplifications. Write amplification degrades the database performance, and space amplification leads to an increased storage space owing to the storage of unwanted data. Previously, it was proven that significant performance improvements can be achieved by tuning the database parameters. However, tuning the multiple parameters of a database is a laborious task owing to the large number of potential configuration combinations. To address this problem, we selected the important parameters that affect the performance of RocksDB using random forest. We then analyzed the effects of the selected parameters on write and space amplifications using analysis of variance. We used a genetic algorithm to obtain optimized values of the major parameters. The experimental results indicate an insignificant reduction (-5.64%) in the execution time when using these optimized values; however, write amplification, space amplification, and data processing rates improved considerably by 20.65%, 54.50%, and 89.68%, respectively, as compared to the performance when using the default settings. [ABSTRACT FROM AUTHOR]

The thermal state of permafrost in the present and future is fundamental to the ecosystem evolution, hydrological process, carbon release, and infrastructure integrity in cold regions. From 2011, we began to establish permafrost monitoring network along the China-Russia crude oil pipelines (CRCOPs) route at the eastern flank of the northern Da Xing'anling Mountains in Northeast China. Based on meteorological data near the southern limit of latitudinal permafrost (SLLP), ground temperature data in 20 boreholes with the depths of 10-60.6 m, soil volumetric liquid water contents and 2-D electrical resistivity tomography (ERT) data, we compiled an integrated dataset of the ground thermal state along the CRCOPs route. Study results demonstrate that permafrost in the vicinity of SLLP has experienced marked warming (2011-2020) to climate change, manifested as the rising permafrost temperatures depth. Local thermal disturbances triggered by the construction and operation of CRCOPs have resulted in significant permafrost warming and subsequent thawing on the right-of-way (ROW) of the pipeline. This permafrost thaw will persist, but it can be alleviated by adopting mitigative measures, such as insulation layer and thermosyphons. The in29 situ observational dataset is of great value for assessing the variability of permafrost under the linear disturbances of the CRCOPs and related environmental effects, for understanding hydro-thermal-mechanical interactions between the buried pipelines and permafrost foundation soils, and for evaluating the operational and structural integrity of the pipeline systems in the future. The dataset is available at the National Tibetan Plateau/Third Pole Environment Data Center (http://doi.org/10.11888/Cryos.tpdc.272357; Li, 2022). [ABSTRACT FROM AUTHOR]

Under a pronounced climate warming, permafrost has been degrading in most areas, but it is still unclear in the northwestern part of the Da Xing'anling Mountains, Northeast China. According to a ten-year observation of permafrost and active-layer temperatures, the multi-year average of mean annual ground temperatures at 20 m was -2.83, -0.94, -0.80, -0.70, -0.60 and -0.49, respectively, at Boreholes GH4, MG3, MG1, MG2, GH5 and YTLH2, with the depths of permafrost table varying from 1.1 to 7.0 m. Ground cooling at shallow depths has been detected, resulting in declining thaw depths in Yituli'he during 2009-2020, possibly due to relatively stable mean positive air temperature and declining snow cover and dwindling local population. In most study areas (e.g., Mangui and Genhe), permafrost warming is particularly pronounced at larger depths (even at 80 m). These results can provide important information for regional development and engineering design and maintenance. [ABSTRACT FROM AUTHOR]

Monitoring of the thermal state of permafrost is important in environmental science and engineering applications. However, such data are generally unavailable mainly due to the lack of ground observations and the uncertainty of traditional physical models. This study produces novel permafrost datasets for the Northern Hemisphere (NH), including predictions of the mean annual ground temperature (MAGT) at the zero annual amplitude depth and active layer thickness (ALT) with a 1- km resolution for the period of 2000–2016, as well as estimates of the probability of permafrost occurrence and permafrost zonation based on hydrothermal conditions. These datasets integrate unprecedentedly large amounts of field data (1,002 boreholes for MAGT and 452 sites for ALT) and multisource geospatial data, especially remote sensing data, using statistical learning modelling with an ensemble strategy. Thus, these data are more accurate than those of previous circumpolar maps (bias=0.02±0.16 °C, RMSE=1.32±0.13 °C for MAGT; bias=2.71±16.46 cm, RMSE=86.93±19.61 cm for ALT). The datasets suggest that the areal extent of permafrost (MAGT≤0 °C) in the NH, excluding glaciers and lakes, is approximately 15.03 (13.84–19.29) ×106 km², and the areal extent of permafrost regions (permafrost probability>0) is approximately 20.14×106 km². The areal fractions of humid, semiarid/subhumid, and arid permafrost regions are 51.84%, 44.83%, and 3.33%, respectively. The areal fractions of cold (≤-3.0 °C), cool (-3.0 °C to -1.5 °C), and warm (>-1.5 °C) permafrost regions are 37.93%, 14.35%, and 47.72%, respectively. These new datasets based on the most comprehensive field data to date contribute to an updated understanding of the thermal state and zonation of permafrost in the NH. They are potentially useful for various fields, such as in climatology, hydrology, ecology, agriculture, public health, and engineering planning. As a baseline, these datasets are also of great importance for evaluating future changes in MAGT, ALT, permafrost extent, and other spatial features of permafrost in the NH. All of the datasets are published through the National Tibetan Plateau Data Center (TPDC), and the link is https://data.tpdc.ac.cn/en/data/5093d9ff-a5fc-4f10-a53f-c01e7b781368 or https://doi.org/10.11888/Geocry.tpdc.271190 (Ran et al., 2021b). [ABSTRACT FROM AUTHOR]

Based on one planned arctic natural gas pipe-line engineering which will cross continuous, discontinuous, sporadic and non-permafrost areas from north to south, with different pipe-line temperatures set, a thermal model of the interaction between pipe-line and permafrost is established to investigate the influence of pipe-lines on the freezing and thawing of frozen soil around pipe-line and thermal stability of permafrost. The results show that different pipe-line temperatures influence the permafrost table greatly. Especially in discontinuous permafrost areas the permafrost table is influenced in both positive temperature and negative temperature. The warm gas pipe-line of 5? could decrease the value of permafrost table about 1 to 3 times pipe diameter and aggravate the degradation of permafrost around pipe-line; -1? and -5? chilled gas pipe-line can effectively improve the permafrost table and maintain the temperature stability of frozen soil, but the temperature of soils below pipe-line of -5? decreases obviously, which may lead to frost heave hazards. In terms of thermal stability around pipe-line, it is advised that transporting temperature of -1? is adopted in continuous permafrost area; in discontinuous permafrost area pipe-line could operate above freezing in the summer months with the station discharge temperature trending the ambient air temperature, but the discharge temperature must be maintained as -1? throughout the winter months; in seasonal freezing soil area chilled pipe-line may cause frost heave, therefore, pipe-line should run in positive temperature without extra temperature cooling control. [ABSTRACT FROM AUTHOR]

Variability of active layer thickness (ALT) in permafrost regions is critical for assessments of climate change, water resources, and engineering applications. Detailed knowledge of ALT variations is also important for studies on ecosystem, hydrological, and geomorphological processes in cold regions. The primary objective of this study is therefore to provide a comprehensive 1971-2000 climatology of ALT and its changes across the entire Northern Hemisphere from 1850 through -100. To accomplish this, in situ observations, the Stefan solution based on a thawing index, and the edaphic factor (E factor) are employed to calculate ALT. The thawing index is derived from (i) the multimodel ensemble mean of 16 models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) over 1850-2005, (ii) three representative concentration pathways (RCP2.6, RCP4.5, and RCP8.5) for 2006--100, and (iii) Climatic Research Unit (CRU) gridded observations for 1901-2014. The results show significant spatial variability in in situ ALT that generally ranges from 40 to 320 cm, with some extreme values of 900 cm in the Alps. The differences in the ALT climatology between the three RCPs and the historical experiments ranged from 0 to 200 cm. The biggest increases, of 120-200 cm, are on the Qinghai-Tibetan Plateau, while the smallest increases of less than 20 cm are in Alaska. Averaged over all permafrost regions, mean ALT from CMIP5 increased significantly at 0.57 ± 0.04 cm decade-1 during 1850-2005, while 2006--100 projections show ALT increases of 0.77 ± 0.08 cm decade-1 for RCP2.6, 2.56 ± 0.07 cm decade-1 for RCP4.5, and 6.51 ± 0.07 cm decade-1 for RCP8.5. [ABSTRACT FROM AUTHOR]

Active layer thickness (ALT) is critical to the understanding of the surface energy balance, hydrological cycles, plant growth, and cold region engineering projects in permafrost regions. The temperature at the bottom of the active layer, a boundary layer between the equilibrium thermal state (in permafrost below) and transient thermal state (in the atmosphere and surface canopies above), is an important parameter to reflect the existence and thermal stability of permafrost. In this study, the Geophysical Institute Permafrost Model (GIPL) was used to model the spatial distribution of and changes in ALT and soil temperature in the Source Area of the Yellow River (SAYR), where continuous, discontinuous, and sporadic permafrost coexists with seasonally frozen ground. Monthly air temperatures downscaled from the CRU TS3.0 datasets, monthly snow depth derived from the passive microwave remote-sensing data SMMR and SSM/I, and vegetation patterns and soil properties at scale of 1:1000000 were used as input data after modified with GIS techniques. The model validation was carried out carefully with ALT in the SAYR has significantly increased from 1.8 m in 1980 to 2.4 m in 2006 at an average rate of 2.2 cm yr. The mean annual temperature at the bottom of the active layer, or temperature at the top of permafrost (TTOP) rose substantially from −1.1°C in 1980 to −0.6°C in 2006 at an average rate of 0.018°C yr. The increasing rate of the ALT and TTOP has accelerated since 2000. Regional warming and degradation of permafrost has also occurred, and the changes in the areal extent of regions with a sub-zero TTOP shrank from 2.4×10 to 2.2×10 km at an average rate of 74 km yr. Changes of ALT and temperature have adversely affected the environmental stability in the SAYR. [ABSTRACT FROM AUTHOR]

Fibromyalgia is a syndrome characterized by chronic widespread pain, stiffness, nonrestorative sleep, fatigue, and comorbid conditions. Recognition of the condition and its associated medications and challenges, along with knowledge of treatment modifications and precautions in drug prescription, can ensure safe and effective delivery of oral health care in fibromyalgia patients. The ever-evolving research into the condition makes it necessary for the oral health care provider to be informed about the current state of the literature and treatment standards regarding the management of fibromyalgia patients. This article reviews the epidemiology, etiology, pathophysiology, and clinical presentation of fibromyalgia, as well as therapeutic advances. Also highlighted are issues that are important to the oral health care provider, including orofacial manifestations and oral health care considerations for patients with fibromyalgia. [ABSTRACT FROM AUTHOR]

The China-Russia Crude Oil Pipeline (CRCOP) goes through 441 km permafrost soils in northeastern China. The bioremediation in case of oil spills is a major concern. So far, little is known about the indigenous bacteria inhabiting in the permafrost soils along the pipeline. A pilot 454 pyrosequencing analysis on the communities from four selected sites which possess high environment risk along the CRCOP is herein presented. The results reveal an immense bacterial diversity than previously anticipated. A total of 14448 OTUs with 84834 reads are identified, which could be assigned into 39 different phyla, and 223 families or 386 genera. Only five phyla sustain a mean OTU abundance more than 5% in all the samples, but they altogether account for 85.08% of total reads. Proteobacteria accounts for 41.65% of the total OTUs or 45% of the reads across all samples, and its proportion generally increases with soil depth, but OTUs numerically decline. Among Proteobacteria, the abundance of Beta-, Alpha-, Delta- and Gamma- subdivisions average to 38.7% (2331 OTUs), 37.5% (2257 OTUs), 10.35% (616 OTUs), and 6.21% (374 OTUs), respectively. Acidobacteria (esp. Acidobacteriaceae), Actinobacteria (esp. Intrasporangiaceae), Bacteroidetes (esp. Sphingobacteria and Flavobacteria) and Chloroflexi (esp. Anaerolineaceae) are also very common, accounting for 8.56% (1237 OTUs), 7.86% (1136 OTUs); 7.35% (1063 OTUs) and 8.27% (1195 OTUs) of total libraries, respectively. The ordination analysis indicates that bacteria communities in the upper active layer cluster together (similar), while bacterial consortia from the lower active layer and permafrost table scatter (less similar). The abundance of Rhodococcus (12 OTUs), Pseudomonas (71 OTUs) and Sphingomonas (87 OTUs) is even less (,0.01%). This effort to profile the background diversity may set the first stage for better evaluating the bacterial dynamics in response to accidental oil spills. [ABSTRACT FROM AUTHOR]

Monitoring of permafrost along the Qinghai-Tibet (Xizang) Highway shows that there is a large difference in the response of permafrost to climate change and to engineering construction. The change in cold (<-1.5°C) permafrost is greater than that in warm (≥-1.5°C) permafrost under the effect of climate change, while the cold permafrost is less sensitive to the disturbances from engineering activities. However, warm permafrost is very sensitive to both climate warming and the impacts from engineering construction. This is because engineering construction has more immediate and direct impacts on the thermal and moisture regimes of underlying permafrost, and consequently greater influence than climate change during the first few years after engineering construction. Assuming constant annual rates of warming, the surface of cold permafrost would approach the warming due to engineering construction in 50 yr, while it would take about 20 yr in areas with warm permafrost. At a depth of 6 m, the temperature rise under engineered surfaces would be reached within 20 and 5-8 yr in cold and warm permafrost, respectively. Therefore, the warming immediately following disturbances of engineering construction would occur naturally in a few years under warm permafrost, but it would take decades for cold permafrost to have the similar thermal effects. Therefore, climate change will have more direct and immediate impacts on the thermal regime of warm permafrost and on the stability and reliability of engineering infrastructures above warm permafrost. [ABSTRACT FROM AUTHOR]

Presents information on a study which provided one of the research results aiming at a preliminary estimate of methane emissions from the cold wetlands on the Qinghai-Tibet Plateau. Methodology of the study; Results and discussion on the study.