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Based on the computed tomography scanning, which abbreviation is CT scanning, and fractal theory, geometric parameters of mudstone fissures are obtained. The physical model of a single fissured channel is obtained in combination with Barton standard curves and 3D printing technology, and similar materials of mudstone are developed based on the water absorption of natural mudstone to prepare single fissured water-absorbing grouting test blocks with different roughness levels for the grouting simulation testing. By analyzing the viscosity change characteristics of grouting slurry before and after grouting, the seepage characteristics of the grouting slurry in the rough fissures of the water-absorbing mudstone are revealed. The results show that when the roughness is small, the grouting slurry will have an obvious water loss effect after passing through mudstone fissures. However, with the flow of the slurry, the water loss effect of the subsequent grouting slurry will be weakened. For fissures with high roughness, the water absorption properties of the rough surfaces and the walls of the mudstone fissures work together, leading to the sedimentation and blockage of the fissure channels, thereby hindering the flow of slurry. [ABSTRACT FROM AUTHOR]

Background: Complete right bundle branch block (CRBBB) is an important predictor of atrial fibrillation (AF) recurrence after pulmonary vein isolation. However, the association between CRBBB and AF development remains unclear. Methods: We performed a retrospective study of 2639 patients (male, n = 1549; female, n = 1090; mean age, 58 ± 13 years). CRBBB was defined as a late R (R′) wave in lead V1 or V2 with a slurred S wave in lead I and/or lead V6 with a prolonged QRS duration (≥120 ms). Results: Among the 2639 patients, CRBBB was detected in 40 patients (1.5%), and the prevalence of AF was 7.4% (196/2639). The proportion of patients with AF and CRBBB was higher than the proportion of patients with AF without CRBBB (22.5% vs. 7.2%; p = 0.001). In the forward multivariate logistic analysis, CRBBB (odds ratio [OR], 3.329; 95% confidence interval [CI], 1.350–8.211; p = 0.009), complete left bundle branch block (OR, 2.209; 95% CI, 1.238–3.940; p = 0.007), age (OR, 1.020; 95% CI, 1.005–1.035; p = 0.009), valvular heart disease (OR, 2.332; 95% CI, 1.531–3.552; p < 0.001), left atrial diameter (OR, 1.133; 95% CI, 1.104–1.163; p < 0.001), left ventricular ejection fraction (OR, 1.023; 95% CI, 1.006–1.041; p = 0.007), and class I or III anti‐arrhythmic drug use (OR, 10.534; 95% CI, 7.090–15.651; p < 0.001) were associated with AF. Conclusion: Complete right bundle branch block was significantly associated with AF development in hospitalized patients with cardiovascular diseases. [ABSTRACT FROM AUTHOR]

The basic endoscopic instruments are not suitable for removing calcified or hard discs in patients with thoracic disc herniations (TDH). We describe a percutaneous endoscopic technique for the treatment of calcified TDH using an endoscopic drill system with a T rigid bendable burr. Eleven patients (8 males, mean age 42.1 years) with single-segmental calcified TDH were treated with percutaneous endoscopic surgeries. Our technique using this endoscopic drill system with a T rigid bendable burr is safe and effective for the treatment of calcified TDH. Percutaneous endoscopic decompression using the T rigid bendable burr is a safe and reproducible surgical procedure for the treatment of calcified TDH. [ABSTRACT FROM AUTHOR]

This study was conducted to assess the compatibility of white shrimp Litopenaeus vannamei and giant freshwater prawn Macrobrachium rosenbergii in the polyculture system. Twelve 0.6 ha intertidal mudflat ponds of shrimp in the region around Hangzhou Bay, China, were divided into four culture systems based on the stocking densities of prawns. The groups were divided into the following: control (CON, no prawn), low stocking density (LSD, 75,000 ha−1), middle stocking density (MSD, 150,000 ha−1) and high stocking density (HSD, 225,000 ha−1) groups. Results showed that the survival (%), final weight, final length and condition factor of reared shrimp exhibited no significant difference among different culture systems. The profits of the polyculture systems significantly increased with prawn stocking density. The mean values of water quality parameters showed no significant difference (p > 0.05) between treatments. Phytoplankton abundance and biomass were significantly reduced in the polyculture groups. Desulforegula (9.39%), Citreicella (4.23%), Gemmobacter (3.66%) and Phycisphaera (2.93%) were the prevailing genera in the CON group. Aeromonas was the most abundant genus in the HSD group. However, most pathogenic bacteria in the pond water were undetected or observed at extremely low levels. The levels of Aeromonas and Pseudomonas sharply increased in the HSD group. These findings suggest that polyculture systems can increase profit without influencing water quality. However, high polyculture at 225,000 ind ha−1 may potentially cause pathogenic bacterial infection. Thus, the recommended model for this polyculture system is shrimp (900,000 ha−1) + prawn (150,000 ha−1). [ABSTRACT FROM AUTHOR]

Fibrosis serves a critical role in driving atrial remodelling‐mediated atrial fibrillation (AF). Abnormal levels of the transcription factor PU.1, a key regulator of fibrosis, are associated with cardiac injury and dysfunction following acute viral myocarditis. However, the role of PU.1 in atrial fibrosis and vulnerability to AF remain unclear. Here, an in vivo atrial fibrosis model was developed by the continuous infusion of C57 mice with subcutaneous Ang‐II, while the in vitro model comprised atrial fibroblasts that were isolated and cultured. The expression of PU.1 was significantly up‐regulated in the Ang‐II‐induced group compared with the sham/control group in vivo and in vitro. Moreover, protein expression along the TGF‐β1/Smads pathway and the proliferation and differentiation of atrial fibroblasts induced by Ang‐II were significantly higher in the Ang‐II‐induced group than in the sham/control group. These effects were attenuated by exposure to DB1976, a PU.1 inhibitor, both in vivo and in vitro. Importantly, in vitro treatment with small interfering RNA against Smad3 (key protein of TGF‐β1/Smads signalling pathway) diminished these Ang‐II‐mediated effects, and the si‐Smad3‐mediated effects were, in turn, antagonized by the addition of a PU.1‐overexpression adenoviral vector. Finally, PU.1 inhibition reduced the atrial fibrosis induced by Ang‐II and attenuated vulnerability to AF, at least in part through the TGF‐β1/Smads pathway. Overall, the study implicates PU.1 as a potential therapeutic target to inhibit Ang‐II‐induced atrial fibrosis and vulnerability to AF. [ABSTRACT FROM AUTHOR]

Ecosystem light use efficiency (LUE) is a critical parameter in estimating CO2 uptake by vegetation from climatological and satellite data. However, the spatiotemporal dynamics and biophysical regulations of ecosystem‐level LUE are not well understood, resulting in large uncertainties in the estimation of gross primary productivity (GPP) using LUE‐based models. In this study, we used eddy covariance to explore spatiotemporal variations and controls of LUE in four contrasting forest ecosystems (savanna, tropical rainforest, subtropical evergreen forest, and subalpine coniferous forest). Based on 27 site years of data, we found that (1) the multiyear mean LUE was 0.063, 0.251, 0.247, and 0.140 g C· mol photon−1 in the four contrasting ecosystems, respectively; (2) the LUE in the wet season (May–October) was higher than that in the dry season in all studied ecosystems; (3) the leaf area index controlled GPP and LUE significantly and explained 74%, 29%, 54%, and 36% of the variation in GPP and 51%, 19%, 41%, and 54% of the variation in LUE in the four contrasting ecosystems, respectively; (4) path analysis revealed the critical roles of GPP and vapor pressure deficit in controlling LUE in these four forest ecosystems; and (5) under warming scenarios, LUE may decrease in savanna but increase in the other three ecosystems, while decreasing precipitation (P) may reduce LUE in the ecosystems studied. This study improves our understanding of the influence of biophysical factors on LUE and demonstrates how LUE changes with variations in temperature, soil moisture, and leaf area index, thereby improving estimations of large‐scale carbon exchange/cycling. Key Points: Evergreen broad‐leaved forest (EBF) ecosystem shows higher LUE than subalpine coniferous/savanna ecosystemsThe vapor pressure deficit (VPD) and leaf area index (LAI) largely determine the variability in LUEWarming might decrease LUE in the savanna ecosystem and may increase LUE in the other three ecosystems [ABSTRACT FROM AUTHOR]

Extreme high temperature is one of important extreme weathers that impact forest ecosystem carbon cycle. In this study, applying CO2 flux and routine meteorological data measured during 2003-2012, we examined the impacts of extreme high temperature and extreme high temperature event on net carbon uptake of subtropical coniferous plantation in Qianyanzhou. Combining with wavelet analysis, we analyzed environmental controls on net carbon uptake at different temporal scales, when the extreme high temperature and extreme high temperature event happened. The results showed that mean daily cumulative NEE decreased by 51% in the days with daily maximum air temperature range between 35 °C and 40 °C, compared with that in the days with the range between 30 °C and 34 °C. The effects of the extreme high temperature and extreme high temperature event on monthly NEE and annual NEE related to the strength and duration of extreme high temperature event. In 2003, when strong extreme high temperature event happened, the sum of monthly cumulative NEE in July and August was only -11.64 g C ⋅ m-2 ⋅ (2 month)-1. The value decreased by 90%, compared with multi-year average value. At the same time, the relative variation of annual NEE reached -6.7%. In July and August, when the extreme high temperature and extreme high temperature event occurred, air temperature (Ta) and vapor press deficit (VPD) were the dominant controller for the daily variation of NEE. The coherency between NEE & Ta and NEE & VPD was 0.97 and 0.95, respectively. At 8-, 16-, and 32-day periods, Ta, VPD, soil water content at 5 cm depth (SWC), and precipitation (P) controlled NEE. The coherency between NEE & SWC and NEE & P was higher than 0.8 at monthly scale. The results indicated that atmospheric water deficit impacted NEE at short temporal scale, when the extreme high temperature and extreme high temperature event occurred, both of atmospheric water deficit and soil drought stress impacted NEE at long temporal scales in this ecosystem. [ABSTRACT FROM AUTHOR]

Global radiation and diffuse radiation were measured from March to June of 2012 in Qianyanzhou Experimental Station of Red Soil and Hilly Land, Chinese Academy of Sciences by using three types of pyranometers, including CMP11 attached with a shadow ring, SPN1 and RSR3, which were placed in parallel. The observations showed that both global radiation and diffuse radiation measured by these pyranometers had a good linear correlation. The global radiation measured by SPN1 and RSR3 was respectively 3.0% and 20.5% lower than that measured by the CMP11. The diffuse radiation measured by SPN1 and RSR3 was respectively 5.5% and 7.9% lower of than that measured by the CMP 11. Under the sunny, cloudy and overcast conditions, the daily variations of diffuse radiation measured by the three pyranometers were similar, and hence, the diffuse radiation values at a specific solar elevation angle measured by the different pyranometers were also similar. There was difference in daily accumulative diffuse radiation measured by the different pyranometers. Monthly diffuse fractions of March, April and May were 0.56, 0.59 and 0.70, respectively. In the subtropical area of southern China, the diffuse radiation accounted for a relatively large proportion of the global solar radiation and varied considerably over time. It is necessary to conduct long-term continuous measurements to capture the variability of diffuse radiation over different underlying surfaces. [ABSTRACT FROM AUTHOR]

Forests in Inner Mongolia account for an important part of the forests in China in terms of their large area and high living standing volume. This study reported carbon storage, carbon density, carbon sequestration rate and carbon sequestration potential of forest ecosystems in Inner Mongolia using the bio-mass carbon data from the related literature. Through analyzing the data of forest inventory and the generalized allometric equations between volume and biomass, previous studies had reported that biomass carbon storage of the forests in Inner Mongolia was about 920 Tg C, which was 12 percent of the national forest carbon storage, the annual average growth rate was about 1. 4%, and the average of carbon density was about 43 t.hm-2. Carbon storage and carbon density showed an increasing trend over time. Coniferous and broad-leaved mixed forest, Pinus sylvestris var. mon-golica forest and Betula platyphylla forest had higher carbon sequestration capacities. Carbon storage was reduced due to human activities such as thinning and clear cutting. There were few studies on carbon storage of the forests in Inner Mongolia with focus on the soil, showing that the soil carbon density increased with the stand age. Study on the carbon sequestration potential of forest eco-systems was still less. Further study was required to examine dynamics of carbon storage in forest ecosystems in Inner Mongolia, i. e. , to assess carbon storage in the forest soils together with biomass carbon storage, to compute biomass carbon content of species organs as 45% in the allometric equations, to build more species specific and site-specific allometric equations including root bio-mass for different dominant species, and to take into account the effects of climate change on carbon sequestration rate and carbon sequestration potential. [ABSTRACT FROM AUTHOR]

Astragalus membranaceus (Fisch.) Bge (AR), one of the most important medicinal plants in Asia, was found to exhibit various bioactivities. Due to limited genomic and transcriptomic data, the biosynthetic pathway of the major bioactive compound in AR, is currently unclear. In this study, 454 GS FLX technology was employed to produce a substantial expressed sequence tag (EST) dataset from the AR. In all, 742721 high-quality reads from the AR were produced using Roche GS FLX Titanium. A total of 9893 unique sequences were obtained and annotated by a similarity search against the public databases, and involved in the secondary metabolic pathway, which would facilitate deciphering the molecular mechanism of secondary metabolism in AR. The assembled sequences were annotated with gene names and Gene Ontology (GO) terms. GO revealed the unique sequences that could be assigned to 34 vocabularies. In the KEGG mapping, unique sequences were established as associated with 46 biochemical pathways. These results provided the largest EST collections in AR and will contribute to biosynthetic and biochemical studies that lead to drug improvement. With respect to the genes related to metabolism and biosynthesis pathway were also found. Our work demonstrated the utility of 454 GS FLX as a method for the rapid and cost-effective identification of AR transcriptome, and this EST dataset will be a powerful resource for further studies such as taxonomy, molecular breeding, and secondary metabolism in AR. [ABSTRACT FROM AUTHOR]

Understanding the dynamics and underlying mechanism of carbon exchange between terrestrial ecosystems and the atmosphere is one of the key issues in global change research. In this study, we quantified the carbon fluxes in different terrestrial ecosystems in China, and analyzed their spatial variation and environmental drivers based on the long-term observation data of China FLUX sites and the published data from other flux sites in China. The results indicate that gross ecosystem productivity ( GEP), ecosystem respiration ( ER), and net ecosystem productivity ( NEP) of terrestrial ecosystems in China showed a significantly latitudinal pattern, declining linearly with the increase of latitude. However, GEP, ER, and NEP did not present a clear longitudinal pattern. The carbon sink functional areas of terrestrial ecosystems in China were mainly located in the subtropical and temperate forests, coastal wetlands in eastern China, the temperate meadow steppe in the northeast China, and the alpine meadow in eastern edge of Qinghai-Tibetan Plateau. The forest ecosystems had stronger carbon sink than grassland ecosystems. The spatial patterns of GEP and ER in China were mainly determined by mean annual precipitation ( MAP) and mean annual temperature ( MAT), whereas the spatial variation in NEP was largely explained by MAT. The combined effects of MAT and MAP explained 79%, 62%, and 66% of the spatial variations in GEP, ER, and NEP, respectively. The GEP, ER, and NEP in different ecosystems in China exhibited 'positive coupling correlation' in their spatial patterns. Both ER and NEP were significantly correlated with GEP, with 68% of the per-unit GEP contributed to ER and 29% to NEP. MAT and MAP affected the spatial patterns of ER and NEP mainly by their direct effects on the spatial pattern of GEP. [ABSTRACT FROM AUTHOR]

By using eddy covariance technique, this paper quantitatively analyzed the photosynthetic characteristics of tropical seasonal rainforest ecosystem and related environmental controlling factors in Xishuangbanna in 2003-2006. In the study period, less interannual difference was observed in the net photosynthesis of the ecosystem, with the maximum photosynthesis rate (Peco,opt), respiration at daytime (Reco,d), and apparent quantum yield (α) averaged by 0.813 mg·m-2 ·s-1, 0.238 mg·m-2·s-1, and 0.0023 mg·μmol-1, respectively. As affected by the interaction of air temperature (Ta) and vapor pressure deficit (VPD), the photosynthetic characteristics had some seasonal differences. In rainy season, the ecosystem had the strongest photosynthetic capacity because of the higher precipitation and warmer air temperature; in foggy and cool season, fog drip played an important role in the water relations of plants, and thereby, the ecosystem photosynthetic capacity was still higher; in dry and hot season, due to the limited precipitation and high temperature, the Ta and VPD increased, inducing a decrease of ecosystem α and Peco,opt. The net CO2 exchange of the ecosystem strongly depended on the Ta above 20 °C and the VPD above 1 kPa. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) storage flux in the air space below measurement height of eddy covariance is very important to correctly evaluate net ecosystem exchange of CO2 (NEE) between forest ecosystem and atmosphere. This study analyzed the dynamic variation of CO2 storage flux and its effects on the carbon budget of a temperate broad-leaved Korean pine mixed forest at Changbai Mountains, based on the eddy covariance flux data and the vertical profile of CO2 concentration data. The CO2 storage flux in this forest ecosystem had typical diurnal variation, with the maximum variation appeared during the transition from stable atmospheric layer to unstable atmospheric layer. The CO2 storage flux calculated by the change in CO2 concentration throughout a vertical profile was not significantly different from that calculated by the change in CO2 concentration at the measurement height of eddy covariance. The NEE of this forest ecosystem was underestimated by 25% and 19% at night and at daytime, respectively, without calculating the CO2 storage flux at half?hour scale, and was underestimated by 10% and 25% at daily scale and annual scale, respectively. Without calculating the CO2 storage flux in this forest ecosystem, the parameters of Michaelis-Menten equation and Lloyd-Taylor equation were underestimated, and the ecosystem apparent quantum yield (α) and the ecosystem respiration rate (Rref) at the reference temperature were mostly affected. The gross primary productivity (GPP) and ecosystem respiration (Re) of this forest ecosystem were underestimated about 20% without calculating the CO2 storage flux at half-hour, daily scale, and annual scale. [ABSTRACT FROM AUTHOR]

Net ecosystem productivity (NEP) was continuously measured using the eddy covariance (EC) technique from 2003 to 2005 at three forest sites of ChinaFLUX. The forests include Changbaishan temperate mixed forest (CBS), Qianyanzhou subtropical coniferous plantation (QYZ), and Dinghushan subtropical evergreen broad-leaved forest (DHS). They span wide ranges of temperature and precipitation and are influenced by the eastern Asian monsoon climate to varying extent. In this study, we estimated ecosystem respiration (RE) and gross ecosystem productivity (GEP). Comparison of ecosystem carbon exchange among the three forests shows that RE was mainly determined by temperature, with the forest at CBS exhibiting the highest temperature sensitivity among the three ecosystems. The RE was highly dependent on GEP across the three forests, and the ratio of RE to GEP decreased along the North–South Transect of Eastern China (NSTEC) (i.e. from the CBS to the DHS), with an average of 0.77 ± 0.06. Daily GEP was mainly influenced by temperature at CBS, whereas photosynthetic photon flux density was the dominant factor affecting the daily GEP at both QYZ and DHS. Temperature mainly determined the pattern of the interannual variations of ecosystem carbon exchange at CBS. However, water availability primarily controlled the interannual variations of ecosystem carbon exchange at QYZ. At DHS, NEP attained the highest values at the beginning of the dry seasons (autumn) rather than the rainy seasons (summer), probably because insufficient radiation and frequent fog during the rainy seasons hindered canopy photosynthesis. All the three forest ecosystems acted as a carbon sink from 2003 to 2005. The annual average values of NEP at CBS, QYZ, and DHS were 259 ± 19, 354 ± 34, and 434 ± 66 g C m−2 yr−1, respectively. The slope of NEP that decreased with increasing latitude along the NSTEC was markedly different from that observed on the forest transect in the European continent. Long-term flux measurements over more forest ecosystems along the NSTEC will further help verify such a difference between the European forest transect and the NSTEC and provide insights into the responses of ecosystem carbon exchange to climate change in China. [ABSTRACT FROM AUTHOR]

To determine anomalous dynamic scaling of continuum growth equations, López12 proposed an analytical approach, which is based on the scaling analysis introduced by Hentschel and Family.15 In this work, we generalize this scaling analysis to the (d+1)-dimensional molecular-beam epitaxy equations to determine their anomalous dynamic scaling. The growth equations studied here include the linear molecular-beam epitaxy (LMBE) and Lai–Das Sarma–Villain (LDV). We find that both the LMBE and LDV equations, when the substrate dimension d>2, correspond to a standard Family–Vicsek scaling, however, when d<2, exhibit anomalous dynamic roughening of the local fluctuations of the growth height. When the growth equations exhibit anomalous dynamic scaling, we obtain the local roughness exponents by using scaling relation αloc=α-zκ, which are consistent with the corresponding numerical results. [ABSTRACT FROM AUTHOR]

A new model of pounding between adjacent structures was brought forward. By establishing the pounding-imposed velocity restraint condition, the pounding analysis is carried out by solving the equations of motion in impulse. The impact force is incorporated implicitly into the governing equations in terms of constraint impulse, which need not be obtained in advance. Moreover, it can be traced out by simple element handling if necessary. In the end, pounding analysis between two frames was performed to show the efficiency of the presented model. [ABSTRACT FROM AUTHOR]