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Digital drilling is a common method for detecting the deep rock mass information, but the cutter wear leads to an irregular shape of the rock chip affecting the detecting accuracy. The detecting methodology lacks the consideration of ground stress and cutter wear. This study developed an analytical model that incorporated confining stress and cutter wear to predict the rock failure surface and required cutting force. Curvature radius is introduced to characterize the failure surface. Triaxial drilling tests were conducted to verify the prediction of the model. The impact of confining stress and cutter wear on the failure patterns was investigated. Failure surface and cutting force were measured to confirm the reliability of the model (approximately 90%). There are two patterns of failure surface, depending on the depth of cut. As the confining stress increases, the predicted cutting force linearly increases, and the curvature radius decreases. Hydrostatic stress has an opposite impact on cutting force and curvature radius, compared to confining stress. This method shows improvement to reduce the sticking phenomenon caused by rock debris. [ABSTRACT FROM AUTHOR]

This cohort study was performed to explore the influence of intensive care unit (ICU) quality on in-hospital mortality of veno-venous (V-V) extracorporeal membrane oxygenation (ECMO)-supported patients in China. The study involved all V-V ECMO-supported patients in 318 of 1700 tertiary hospitals from 2017 to 2019, using data from the National Clinical Improvement System and China National Critical Care Quality Control Center. ICU quality was assessed by quality control indicators and capacity parameters. Among the 2563 V-V ECMO-supported patients in 318 hospitals, a significant correlation was found between ECMO-related complications and prognosis. The reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients (cutoff: 1.5% and 7.0%; 95% confidence interval: 1.05–1.48 and 1.04–1.45; odds ratios: 1.25 and 1.23; P = 0.012 and P = 0.015, respectively). Meanwhile, the V-V ECMO center volume was a protective factor (cutoff of ≥ 50 cases within the 3-year study period; 95% confidence interval: 0.57–0.83, odds ratio: 0.69, P = 0.0001). The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these findings. Thus, ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients. [ABSTRACT FROM AUTHOR]

Hierarchical compartmentalization, a hallmark of both primitive and modern cells, enables the concentration and isolation of biomolecules, and facilitates spatial organization of biochemical reactions. Coacervate-based compartments can sequester and recruit a large variety of molecules, making it an attractive protocell model. In this work, we report the spontaneous formation of core-shell cell-sized coacervate-based compartments driven by spontaneous evaporation of a sessile droplet on a thin-oil-coated substrate. Our analysis reveals that such far-from-equilibrium architectures arise from multiple, coupled segregative and associative liquid-liquid phase separation, and are stabilized by stagnation points within the evaporating droplet. The formation of stagnation points results from convective capillary flows induced by the maximum evaporation rate at the liquid-liquid-air contact line. This work provides valuable insights into the spontaneous formation and maintenance of hierarchical compartments under non-equilibrium conditions, offering a glimpse into the real-life scenario. Coacervate-based compartments are attractive as potential protocells, but formation and control of the compartments can be challenging. Here, the authors report the spontaneous formation of core-shell, cell-sized coacervate compartments driven by droplet evaporation. [ABSTRACT FROM AUTHOR]

Anisotropy is an inherent property of rocks. It refers to the different response of the rock properties in each direction. Understanding the anisotropy characteristics of rock failure by drilling has practical applications in improving drilling efficiency, especially for engineering applications. In this paper, a criterion is established to clarify the ductile-to-brittle transition in the drilling process of rock. Moreover, a new anisotropy index has been proposed to evaluate the effect of anisotropy on the critical state of the ductile-to-brittle transition. The digital drilling tests are conducted on six types of rock to study the drilling mechanical performance in the X, Y, and Z directions. The anisotropy characteristics of drilling parameters and mechanical specific energy (MSE) are analysed at the critical state of ductile–brittle failure. The results show that the critical state of ductile–brittle failure is manifested as an inflection point of the depth of cut. The evolution of MSE is fitted as two linear functions, which corresponds to the two stages. The order of anisotropy in MSE is obtained as: gneiss > slate > red sandstone > granite > argillaceous sandstone > sandstone. The anisotropy in the uniaxial compressive strength and MSE for different rock types has the same sequences. The advantages of the proposed method in determining rock anisotropy are illustrated. [ABSTRACT FROM AUTHOR]

This study aimed to explore key quality control factors that affected the prognosis of intensive care unit (ICU) patients in Chinese mainland over six years (2015–2020). The data for this study were from 31 provincial and municipal hospitals (3425 hospital ICUs) and included 2 110 685 ICU patients, for a total of 27 607 376 ICU hospitalization days. We found that 15 initially established quality control indicators were good predictors of patient prognosis, including percentage of ICU patients out of all inpatients (%), percentage of ICU bed occupancy of total inpatient bed occupancy (%), percentage of all ICU inpatients with an APACHE II score ⩾15 (%), three-hour (surviving sepsis campaign) SSC bundle compliance (%), six-hour SSC bundle compliance (%), rate of microbe detection before antibiotics (%), percentage of drug deep venous thrombosis (DVT) prophylaxis (%), percentage of unplanned endotracheal extubations (%), percentage of patients reintubated within 48 hours (%), unplanned transfers to the ICU (%), 48-h ICU readmission rate (%), ventilator associated pneumonia (VAP) (per 1000 ventilator days), catheter related blood stream infection (CRBSI) (per 1000 catheter days), catheter-associated urinary tract infections (CAUTI) (per 1000 catheter days), in-hospital mortality (%). When exploratory factor analysis was applied, the 15 indicators were divided into 6 core elements that varied in weight regarding quality evaluation: nosocomial infection management (21.35%), compliance with the Surviving Sepsis Campaign guidelines (17.97%), ICU resources (17.46%), airway management (15.53%), prevention of deep-vein thrombosis (14.07%), and severity of patient condition (13.61%). Based on the different weights of the core elements associated with the 15 indicators, we developed an integrated quality scoring system defined as F score=21.35%xnosocomial infection management + 17.97%xcompliance with SSC guidelines + 17.46%×ICU resources + 15.53%×airway management + 14.07%×DVT prevention + 13.61%×severity of patient condition. This evidence-based quality scoring system will help in assessing the key elements of quality management and establish a foundation for further optimization of the quality control indicator system. [ABSTRACT FROM AUTHOR]

Selenium (Se) is essential to human health, anti-cancer, possessing antioxidant, and antiviral properties. In this study, the spatial patterns of rice Se and their varying relationship with soil Se on a regional scale were studied using hot spot analysis for the agricultural soils in Guangxi. According to the hot and cold spot maps, rice Se correlates positively with soil Se in Guangxi agricultural soils. High rice Se accompanies high soil Se in the central part of Guangxi (e.g., Liuzhou, Laibin), and low rice Se is in line with low soil Se in the western part (e.g., Baise). However, the hot spot analysis maps indicate that southwestern Guangxi exhibits a special characteristic of low rice Se with high soil Se (e.g., Chongzuo). This special pattern is strongly associated with the high concentrations of Fe2O3 (ferromanganese nodules) in the carbonate rock area. The hot spot analysis proves useful in revealing the spatial patterns of rice Se in Guangxi and identifying the hidden patterns. [ABSTRACT FROM AUTHOR]

Riverbank erosion is a common natural river process that threatens the security of in-stream structures as well as public and private properties. The impacts of riparian vegetation on the riverbank erosion processes are still unclear. This study conducted flume experiments with artificial riverbanks and living vegetation to investigate the effects of riverbank vegetation conditions on the riverbank erosion process. Two riverbank types, nonvegetation and vegetation riverbanks, with three growth times of vegetation (T = 15, 30, and 60 d) were compared and discussed. The results show that the erosion form on vegetation riverbanks is the individual particles, whereas it is a large block of soil on nonvegetation riverbanks. The equilibrium channel width, riverbank erosion volume, and bed deposition of the vegetation riverbank are lower than those of the nonvegetation riverbank. As the vegetation growth time increases, the equilibrium channel width, riverbank erosion volume, and bed deposition volume decrease. The experimental data also indicate that the temporal channel width of the nonvegetation riverbank is greater than that of the vegetation riverbank; the lower the vegetation growth time, the greater the temporal channel width. Highlights: This study was conducted by planting real vegetation on a riverbank. Riparian vegetation can increase the stability of riverbanks because of mechanical, hydrological, and hydraulic effects. The erosion form on vegetation riverbanks is the individual particles, whereas it is a large block of soil on nonvegetation riverbanks. [ABSTRACT FROM AUTHOR]

The structure and characteristics of high-performance lightweight aggregates produced by high-carbon gasification slag were investigated by X-ray diffraction, scanning electron microscopy, thermogravimetry/differential thermogravimetr, differential scanning calorimetry-Fourier transform infrared, and mercury intrusion porosimetry, respectively. The experimental results show that the ceramsite undergoes two weightless stages in the calcining process. With the increase in the calcining temperature, a large number of pores are formed inside the ceramsite, its structure becomes denser, but the calcining temperature band of the ceramsite becomes narrow. The crystalline phase of the ceramsite changes at different calcining temperatures and the mineral phase changes from the earlieralbite, quartz, oligoclase, hematite, etc, to a silica-aluminum-rich glass phase. The 1 130 °C is a more suitable calcining temperature, and the cylinder compressive strength of ceramics is 11.59 MPa, the packing density, apparent density, porosity, and water absorption are 939.11 kg/m3, 1643.75 kg/m3, 28.11%, and 10.35%, respectively, which can meet the standards for high-strength lightweight aggregates. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the protective effects of PPARγ/CPT-1 regulation on cisplatin-induced cochlear hair cell injury. The viability, apoptosis and mitochondrial membrane potential of cisplatin-induced HEI-OC1 cells were determined by CCK-8 assay, TUNEL and JC-1 staining, respectively. The oxidative stress and lipid metabolism were detected by the assay kits of MDA, ROS, SOD, CAT, TG and FFA. The transfection efficiency of overexpression (OV)-PPARG and OV-CPT1A was examined by RT-qPCR and the expressions of apoptosis- and lipid metabolism-related proteins were detected by western blot. As a result, cisplatin with varying concentrations (5, 10, 30 μM) suppressed the viability, promoted the apoptosis and hindered the mitochondrial function of HEI-OC1 cells, accompanied with up-regulated expressions of Bax and cleaved caspase-3 and down-regulated expression of Bcl-2. The oxidative stress was aggravated and lipid metabolism was inhibited by cisplatin (5, 10, 30 μM) induction, evidenced by the increased levels of MDA, ROS, TG, FFA and the decreased levels of SOD and CAT. Overexpression of PPARG or CPT1A could improve the viability, mitochondrial function, lipid metabolism and suppress the oxidative stress and apoptosis of cisplatin-induced HEI-OC1 cells. In conclusion, up-regulation of PPARG or CPT1A ameliorated cochlear hair cell injury by improving cellular lipid metabolism and inhibiting oxidative stress. [ABSTRACT FROM AUTHOR]

Septic shock, largely caused by intestinal perforation, is a common critical disease in intensive care unit (ICU). For hospitals and health systems, a performance improvement program for sepsis was strong recommended in guidelines. Numerous studies have shown that improved quality control improves outcomes in patients with septic shock. Nevertheless, association between quality control and outcomes of septic shock caused by intestinal perforation are not fully revealed. Thus we designed this study to investigate effects of quality control on septic shock caused by intestinal perforation in China. This was a multicenter observational study. A total of 463 hospitals were enrolled in this survey, led by the China National Critical Care Quality Control Center (China-NCCQC) from January 1, 2018 to December 31, 2018. In this study, the indicators of quality control included the proportion of ICU patient bed occupancy to total inpatient bed occupancy, the proportion of ICU patients with APACHE II score ≥ 15, and the microbiology detection rate before antibiotic use. The outcome indicators included hospital stays, hospitalization costs, complications, and mortality. Generalized linear mixed models were used to analyse the association between quality control and septic shock caused by intestinal perforation. The proportion of ICU patient bed occupancy to total inpatient bed occupancy is positively correlated with hospital stays, incidence of complications (ARDS, AKI) and costs in septic shock caused by intestinal perforation (p < 0.05). The proportion of ICU patients with APACHE II score ≥ 15 was not associated with hospital stays and incidence of ARDS and AKI (p < 0.05). Increasing of the proportion of ICU patients with APACHE II score ≥ 15 decreased the costs of patients with septic shock caused by intestinal perforation (p < 0.05). The microbiology detection rate before antibiotic use was not associated with hospital stays, incidence of AKI and costs of patients with septic shock caused by intestinal perforation (p < 0.05). Surprisingly, the increase of microbiology detection rate before antibiotic use increased the incidence of ARDS in patients with septic shock caused by intestinal perforation (p < 0.05). The above three indicators of quality control were not associated with mortality of the patients with septic shock caused by intestinal perforation. On the one hand, the number of ICU patients admitted should be controlled to reduce the proportion of ICU patients out of total inpatient bed occupancy. On the other hand, intensive care unit admission of severe patients (patients with APACHE II score ≥ 15) should be encouraged to improve the proportion of patients with APACHE II score ≥ 15 in the ICU, so that ICU can focus more on the treatment of severe patients and promote the professionalization of severe patient management. It is not advisable to collect sputum specimens too frequently for patients without pneumonia. [ABSTRACT FROM AUTHOR]

Microcystins (MCs) in irrigation water could inhibit crop growth and yield. Protein phosphatases (PPs) play an important role in regulating physiological mechanisms in plants to adapt abiotic stresses. To clarify the adaptation mechanism in plants to MCs stress, we compared PPs in rice and cucumber leaves by analyzing PPs total activity, protein phosphatase-2A (PP2A) activity and expression, as well as related growth and gas exchange parameters. After 7-day exposure of MCs (5 ~ 100 µg/L) and 7-day recovery without MCs, rice showed higher tolerance to MCs by analyzing dry weight and gas exchange parameters. Both crops may regulate PPs activity to adapt MCs stress by increasing the expression of genes encoding PPs. Among them, PP2A activity in two crops showed more sensitivity to MCs than total PPs activity. In addition, the higher expressions of PP2A catalytic and regulatory subunits and lower decrease PP2A activity were observed in rice leaves compared to cucumber. All results suggest that the expression levels of PP2A subunits could play a role in maintaining the activity of PP2A to regulating plant tolerance to MCs stress. [ABSTRACT FROM AUTHOR]

To determine whether the national soil heavy metal standards (GB 15618-2018) are applicable to some carbonate and non-carbonate zones in Southwest China, rice and rhizosphere soil samples were collected in Chongqing and analyzed for heavy metal contents, pH, and other chemical parameters. In addition, regression analysis was also used to predict the risk threshold of soil heavy metals. The Cd risk screening value in GB 15618-2018 was strict for alkaline soils (pH > 7.5) as compared to those revealed in carbonate and non-carbonate areas, while the calculated pollution threshold for Cd in acidic soils (pH ≤ 5.5) in the non-carbonate area was lower than that in GB 15618-2018. Therefore, to improve the applicability of the evaluation results, a soil-crop system evaluation is recommended. [ABSTRACT FROM AUTHOR]

The vapor compression heat pump is considered as the best option for aerospace thermal control system. The heat exchanger in vapor compression heat pump is a component that is greatly influenced by the cosmic environment. Lubricating oil enters heat pump system with a refrigerant under microgravity, and the entrance of the lubricant increases the complexity of the flow. In this work, FLUENT software was used to study the flow and lubricant deposition of a two-phase mixture of lubricant POE RL 68H and refrigerant R134a in a heat exchanger without the consideration of phase-change heat transfer. The functional relationships between the oil film thickness and the proportion of lubricating oil, the gravitational acceleration, the inlet flow velocity, and the placement directions of the two phases of oil in the heat exchanger were established. The results demonstrate that with the increase of the gravitational acceleration and the lubricating oil content, the thickness of the oil film will exhibit an S-type change in line with the Boltzmann function, and the amount of lubricating oil deposition will increase. With the increase of the flow velocity, the thickness of the oil film will exhibit an exponential decline. [ABSTRACT FROM AUTHOR]

Dysregulation of protein O-fucosyl transferase 1 (POFUT1) contributes to the occurrence and progression of multiple cancers. However, whether POFUT1 has a relationship with the pathogenesis of glioblastoma (GBM) is unknown. This work was aimed at evaluating the detailed relevance of POFUT1 in GBM. Here, we demonstrated high levels of POFUT1 in GBM tissue and elucidated that GBM patients with high levels of POFUT1 had a shorter survival rate than those with low levels of POFUT1. POFUT1 knockdown in GBM cells markedly downregulated the ability to proliferate and invade, while overexpression of POFUT1 potentiated the proliferative and invasive ability of GBM cells. Further mechanistic studies indicated that silencing POFUT1 prohibited the activation of Notch signaling, leading to a reduction in the expression of HES1 and HEY1. On the contrary, overexpression of POFUT1 enhanced the activation of Notch signaling. Notably, inhibition of Notch signaling markedly reversed POFUT1-overexpression-induced tumor promotion effects in GBM cells. In addition, POFUT1 silencing markedly repressed the potential of GBM cells to form tumors in vivo. In conclusion, the data of this work indicates that POFUT1 serves a tumor promotion role in GBM by enhancing the activation of Notch signaling. This study underlines the potential role of the POFUT1/Notch axis in GBM progression and proposes POFUT1 as a promising anticancer target for GBM. [ABSTRACT FROM AUTHOR]

Microcystins (MCs) in water for irrigation may damage crop growth and enter food chains to threaten human health. To evaluate the potential risk of irrigation water contaminated with MCs, we exposed rice at each of the seedling, booting, and filling stages to irrigation water spiked with MCs at 1, 10, 100, and 1000 μg/L for 7 days. Afterwards, all rice underwent a recovery (without MCs) till the harvest. Low MCs (1 or10 μg/L) during different rice growth stages did not affect its yield and nutritional quality and had no risk to human health. High-concentration MCs (100 or 1000 μg/L) during the seedling or booting stage caused a larger decrease in the nutritional quality and yield of rice grains than that during the filling stage. In addition, MCs at 100 μg/L during the booting stage or at 1000 μg/L during the filling stage potentially threatened human health. The effect of MCs on rice yield, quality, and health risk was associated with the MC concentration and rice growth stage. Irrigation water contaminated with moderate-concentration MCs should be of concern at the early growth stage of rice. [ABSTRACT FROM AUTHOR]

For outdoor ground/watersurface multi-scene applications with sparse feature points, high moving speed and high dynamic noises, a real-time 3D LIDAR SLAM system (S4-SLAM) for unmanned vehicles/ships is proposed in this paper, which is composed of the odometry function in front-end and the loop closure function in back-end. Firstly, linear interpolation is used to eliminate the motion distortion caused by robot motions in the data pre-processing step. Two nodes are constructed in the odometry function: the localization node combines the improved Super4PCS with the standard ICP to realize a coarse-to-fine scan matching and outputs the location information of the robot at a high frequency (5 Hz); the correction node introduces a local map with dynamic voxel grid storage structure, which can accelerate the NDT(Normal Distributions Transform) matching process between key-frames and the local map, and then corrects the localization node at a low frequency (1 Hz) to obtain more accurate location information. In the loop closure function, a location-based loop detection approach is introduced and the overlap rate of point clouds is used to verify the loops, so that the global optimization can be carried out to obtain high-precision trajectory and map estimates. The proposed method has been extensively evaluated on the KITTI odometry benchmark and also tested in real-life campus and harbor environments. The results show that our method has low dependence on GPS/INS, high positioning accuracy (with the global drift under 1%) and good environmental robustness. [ABSTRACT FROM AUTHOR]

Learning to grasp novel objects is a challenging issue for service robots, especially when the robot is performing goal-oriented manipulation or interaction tasks whilst only single-view RGB-D sensor data is available. While some visual approaches focus on grasping that satisfy force-closure standards only, we further link affordances-based task constraints to the grasp pose on object parts, so that both force-closure standard and task constraints can be ensured. In this paper, a new single-view approach is proposed for task-constrained grasp pose detection. We propose to learn a pixel-level affordance detector based on a convolutional neural network. The affordance detector provides a fine grained understanding of the task constraints on objects, which are formulated as a pre-segmentation stage in the grasp pose detection framework. The accuracy and robustness of grasp pose detection are improved by a novel method for calculating local reference frame as well as a position-sensitive fully convolutional neural network for grasp stability classification. Experiments on benchmark datasets have shown that our method outperforms the state-of-the-art methods. We have also validated our method in real-world and task-specific grasping scenes, in which higher success rate for task-oriented grasping is achieved. [ABSTRACT FROM AUTHOR]

B and C The levels of MDA, ROS, SOD and CAT in HEI-OC1 cells induced by different concentrations of cisplatin were detected by corresponding assay kits. Correction: Regulation of PPAR /CPT-1 expression ameliorates cochlear hair cell injury by regulating cellular lipid metabolism and oxidative stress A The viability of HEI-OC1 cells induced by different concentrations of cisplatin was detected by CCK-8 assay. [Extracted from the article]

Al/Mg–Li/Al composite plates were fabricated by hot rolling with 50% thickness reduction at 673 K and annealed at 473–673 K for 1 h. The microstructure and mechanical properties of the composite plates under different annealing temperatures were investigated. The results show that the composite plates with a good bonding interface are fabricated. The diffusion layer consisting of Al3Mg2, Al12Mg17, AlLi, and MgLiAl2 has formed at the interface after annealing at and above 623 K, while the interfacial bonding strength increases with the annealing temperature. The microhardness of the interface increases rapidly when the annealing temperature is above 573 K. The elongation of the composite plate increases with annealing temperature. The tensile strength decreases when annealing temperature is above 573 K. [ABSTRACT FROM AUTHOR]

Neuronal apoptosis is a potentially fatal pathological process that occurs in early brain injury (EBI) after subarachnoid hemorrhage (SAH). There is an urgent need to identify effective therapeutics to alleviate neuronal apoptosis. Tetramethylpyrazine (TMP), as an important component of the Chinese traditional medicinal herb Ligusticum wallichii, has been widely used in China to treat cerebral ischemic injury and confer neuroprotection. In the present work, we investigate whether TMP can reduce EBI following SAH in rats, specifically via inactivating the PERK/Akt signaling cascade. One hundred twenty-five male Sprague-Dawley rats were used in the present study. TMP was administered by intravenous (i.v.) injection, and the Akt inhibitor MK2206 was injected intracerebroventricularly (i.c.v.). SAH grade, neurological scores, and brain water content were measured 24 h after SAH. Neuronal apoptosis was visualized by Fluoro-Jade C (FJC) staining. Western blotting was used to measure the levels of PERK, p-PERK, eIF2α, p-eIF2α, Akt, p-Akt, Bcl-2, Bax, and cleaved caspase-3. Our results showed that TMP effectively reduced neuronal apoptosis and improved neurobehavioral deficits 24 h after SAH. Administration of TMP reduced the abundance of p-PERK and p-eIF2α. In addition, TMP increased the p-Akt level and the Bcl-2/Bax ratio and decreased the level of cleaved caspase-3. The selective Akt inhibitor MK2206 abolished the anti-apoptotic effect of TMP at 24 h after SAH. Collectively, these results indicate that Akt-related anti-apoptosis through the PERK pathway is a major, potent mechanism of EBI. Further investigation of this pathway may provide a basis for the development of TMP as a clinical treatment. [ABSTRACT FROM AUTHOR]

This paper presents the deformation behavior and crashworthiness of electric resistance welded mild steel tubes with axial gradient microstructures in quasi-static compression. Three sets of tubes were prepared, and regions of each tube were Induction heated and directly quenched (IH-DQ). The effect of the length to diameter ( L/ D) ratio, and length of the IH-DQ region on crushing characteristics was investigated, and compared with untreated tubes. The compression tests revealed that improved energy absorption can be obtained in IHDQ tubes if the collapse is controlled by the formation of a concertina buckling mode. However, there was a tendency to produce mixed or Euler buckling modes as the ratio of L/ D increased. Meanwhile, the results of the crush experiments and the FEM models showed that the heat-treatment process should be precisely controlled to produce the correct type of microstructure, and circumferential uniformity of microstructure distribution. [ABSTRACT FROM AUTHOR]

A probabilistic algorithm is proposed for the problem of simultaneous robot localization and people-tracking (SLAP) using single onboard sensor in situations with sensor noise and global uncertainties over the observer's pose. By the decomposition of the joint distribution according to the Rao-Blackwell theorem, posteriors of the robot pose are sequentially estimated over time by a smoothed laser perception model and an improved resampling scheme with evolution strategies; the conditional distribution of the person's position is estimated using unscented Kalman filter (UKF) to deal with the nonlinear dynamic of human motion. Experiments conducted in a real indoor service robot scenario validate the favorable performance of the positional accuracy as well as the improved computational efficiency. [ABSTRACT FROM AUTHOR]

The 2.5 Ga Guyang greenstone belt is a major lithological unit in the northwestern part of the North China Craton. Komatiites have recently been identified to occur within the lower part of the meta-volcanic sedimentary sequence of the greenstone belt. The biggest komatiite near Guyang has been mapped out, which is 500 m long and 50 m wide lenticular block. Re-Os isotopic compositions of 9 samples were analyzed to date the komatiites. The Os contents are from 0.88 to 2.63 ppb, identical with typical komatiites, and slightly lower than the normal mantle. The 187Os/188Os ratios are from 0.1115 to 0.1197, which are lower enough to exclude the origin of Phanerozoic magma as widely developed in adjacent areas. The calculated Re depletion model ages (TRD) are from 1346 to 2454 Ma, among them the oldest age of 2454 Ma gives the minimum evaluation for the formation age of the Guyang komatiite. Therefore, the komatiites are a part of the Guyang greenstone belt, indicating high degree melting of mantle during ~2.5 Ga crustal growth event. [ABSTRACT FROM AUTHOR]

This paper presents a novel method, which enhances the use of external mechanisms by considering a multisensor system, composed of sonars and a CCD camera. Monocular vision provides redundant information about the location of the geometric entities detected by the sonar sensors. To reduce ambiguity significantly, an improved and more detailed sonar model is utilized. Moreover, Hough transform is used to extract features from raw sonar data and vision image. Information is fused at the level of features. This technique significantly improves the reliability and precision of the environment observations used for the simultaneous localization and map building problem for mobile robots. Experimental results validate the favorable performance of this approach. [ABSTRACT FROM AUTHOR]

Recently, MDM4 gene has been reported to be a susceptibility gene for glioma in Europeans, but the molecular mechanism of glioma pathogenesis remains unknown. The aim of this study was to investigate whether common variants of MDM4 contribute to the risk of glioma in Han Chinese individuals. A total of 24 single-nucleotide polymorphisms (SNPs) of the MDM4 gene were assessed in a dataset of 562 glioma patients (non-glioblastoma) and 1,192 cancer-free controls. The SNP rs4252707 was found to be strongly associated with the risk of non-GBM (P = 0.000101, adjusted odds ratio (OR) = 1.34, 95% confidence interval (CI) = 1.16–1.55). Further analyses indicated that there was a significant association between A allele of rs4252707 associated with the increased non-GBM risk. Haplotype analysis also confirmed a result similar to that of the single-SNP analysis. Using stratification analyses, we found the association of rs4252707 with an increased non-GBM risk in adults (≥18 years, P = 0.0016) and individuals without IR exposure history (P = 0.0013). Our results provide strong evidence that the MDM4 gene is tightly linked to genetic susceptibility for non-GBM risk in Han Chinese population, indicating a important role for MDM4 gene in the etiology of glioma. [ABSTRACT FROM AUTHOR]

Sediment supply governs the bedload transport and bed morphology in rivers. Up to the present, the impacts of magnitude and texture of variable sediment supply (e.g., induced by flash flood from tributaries) on bedload transport are unknown, limiting the capacity of flood control and river management significantly. The present study conducted flume experiments to investigate the responses of bedload transport to variable sediment supply regimes with different peak supply rates and grain size distributions. The experimental results indicate that: the bedload rate and mass increase with increasing the peak rate of the variable sediment supply, and decrease with an increase in the proportion of coarse particles; the particles coarser than the median grain size of the supplied sediment D50 are primarily stored in the bed, while those finer than D50 are mainly transported downstream; during the variable sediment supply process, the critical Shields stress of sediment has a similar development trend to that of the bedload rate but with a slight ahead of time. [ABSTRACT FROM AUTHOR]