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Spatial distribution orientations of blocks can cause significant errors in the discrete element model (DEM) calculation of soil-rock mixture (SRM). To avoid this error, spherical harmonic (SH) series whose harmonization degrees fixed at 15 were proposed for block reconstruction. This research refers to the case-history of a deep excavation rift valley spanning from the Mabian to Zhaojue section of the Leshan-Xichang Expressway, mainly containing moderately-weathered silty mudstone, in the Leshan City, Sichuan Province, China. The appropriate degree of finite-term SH series is selected by the volume, surface area. 100 blocks were scanned on site, and sphericity and angularity of the blocks were calculated. The sphericity and angularity of 50 reconstructed blocks were considered for the error analysis of SH method. Moreover, stochastic polyhedron method was considered for comparing different block reconstructions. The maximum block placement angle was defined to control the spatial distribution orientations of the blocks. Large scale direct tests were carried. Numerical simulations of large-scale direct shear tests were conducted to study the influence of the spatial distribution orientations of the blocks on the mechanical properties of the SRMs. The results revealed that the finite-term SH series fixed at 15 accurately reflected the shape characteristics and mechanical behaviors of actual blocks. The spatial distribution orientations of the blocks had a minimal impact on the friction angle and cohesion of SRM constructed through the SH method. The SRMs developed via the SH method exhibited marginal variations in contact force and anisotropy index of contact across diverse block placement strategies. The evolution of coordination number was closer when employing the SH method under varied block placement methods. Blocks reconstructed by the SH method, could mitigate errors in DEM calculation caused by the spatial distribution orientations of the blocks. [ABSTRACT FROM AUTHOR]

Geological events that cause casualties and huge property losses frequently occur in the hilly region of Southwest China. Especially for economically underdeveloped mountainous cities, the vulnerability of social and ecological systems greatly affects urban development. Therefore, it is necessary to conduct multi-hazard exposure research in mountain areas. The importance of this study is that the five machine learning algorithms: Support Vector Machine (SVM), Random Forest (RF), eXtreme Gradient Boosting (XGBoost), Light Gradient Boosting Machine (LightGBM) and Categorical Boosting (CatBoost) are first used to develop multi-hazard (specifically landslides and rockfalls) susceptibility map in three typical hilly areas in the Southwest China (Qijiang, Chuishui and Wuxi). The performances of the models are then compared using the F1-Score and the true skill score (TSS) respectively. Finally, the multi-hazard exposure maps of each district are developed by combining multi-hazard susceptibility and exposure factors. According to the results of this study, it can be found that the LightGBM and CatBoost algorithms are suitable for the development of landslide and rockfall hazard susceptibility maps in the hilly region of southwest China, and this type of gradient boosting algorithms have good development prospects. In addition, in future research on geological hazards in this hilly area, more attention should be paid to conditioning factors such as rainfall, altitude, slope, distance from the faults, and lithology. The results of this study can provide reference for the screening of landslide and rockfall conditioning factors in such mountainous areas, and can also provide certain support for the planning of the social ecosystem in mountainous areas and the formulation of natural hazard mitigation measures. [ABSTRACT FROM AUTHOR]

Rockfall has become one of the deadliest geohazards in Southwest China and how to comprehensively and effectively assess rockfall hazards is an urgent challenge to overcome. Additionally, comprehensive characterization of fractures on rock mass outcrops is a prerequisite for detecting potential rockfall. In this paper, an image and point cloud-based data fusion technique is applied to characterize regional rock mass fractures. Firstly, the performances of three classical computer vision algorithms are compared and SegFormer is selected as the appropriate base model for fracture detection. After that, according to the coordinate projection transformation criterion, the detected fractures are mapped to the point cloud. The parameter information obtained through fracture characterization is used to develop a representative three-dimensional discrete fracture network (3D-DFN) and then according to the results of the volume distribution of rock blocks, the three frequencies (high-frequency, medium-frequency, and low-frequency) of rockfall events are numerically simulated to obtain the characteristic information of rockfall trajectories. Finally, based on the characteristic information of rockfall trajectories and the GIS platform, the risk of rockfall hazards with three frequencies is evaluated and analyzed. This paper provides a new way for geologists to assess the risk of rockfall hazards and propose reasonable rockfall hazard prevention schemes. [ABSTRACT FROM AUTHOR]

Hospitals become more involved in the development of the healthy community and are usually important factors influencing housing values. Proximity to hospitals has been found to pose negative effects on surrounding housing values. However, hospitals are considered as a type of urban facility only accounting for their geographic locations when analyzing the effects of hospitals on housing prices. The attributes of hospitals and their diverse effects on different quantiles values of housing have been little scrutinized during the analysis. In this study, we examined the impact of hospital accessibility on surrounding housing prices simultaneously accounting for the heterogeneity of hospitals attributes, geospatial locations and housing price quantiles. We classified the values of hospitals accessibility by three walking distance (e.g., under 5 min, 6–10 min, 11–15 min) and coupled these walking accessibility values with three types of hospitals in Shanghai, China (e.g., primary, secondary, and tertiary). We incorporated a spatial econometric model and a quantile regression model to examine the association between these newly classified housing accessibility values and housing prices. Results showed that (1) higher-tier hospitals are spatially associated with higher values of housing. (2) The accessibility premiums and proximity penalties simultaneously exist in the impact of hospitals on housing prices. Specifically, the walking distances of 5- to 10-min to primary and secondary hospitals and of 10- to 15-min to tertiary hospitals all increased housing prices in surrounding areas. However, walking distances of less than 10 min to tertiary hospitals led to lower housing prices. (3) Potential buyers of all-priced housing would be willing to pay more for housing because of good accessibility to hospitals, but their requests varied across groups. This study proposes a framework for analyzing housing prices accounting for both the amenity and the dis-amenity features of hospitals. The findings would inform urban planning and policy interventions to build a healthy community. [ABSTRACT FROM AUTHOR]

Under the wave of globalization, some cities in China, especially the so-called "megacities" are entering or have already entered the stage of post-suburbanization. The study places Shanghai suburbs in the post-suburbanization landscape and takes Qingpu New Town as an example to systematically analyze the development and formation mechanism of post-suburbanization spaces. This study reveals the features of the post-suburbanization in China as follows. Firstly, In China, post-suburbanization is achieved based on industrialization as well as on the promotion of urbanization. Although urbanization has strengthened other functions of suburban spaces aside from living and production, the production attributes of suburbs remain stable. Secondly, post-suburbanization space with the new town as the development model is an important path for a new round of suburban space growth, it has expanded the space for capital accumulation in metropolitan areas, thus promoting the possibility of reorganizing economic activities within metropolitan areas. At the same time, it focuses on the integration of industries and cities, and the simultaneous development of urbanization and industrialization. In turn, this promotes the accumulation of capital centered on the urban environment and manufacturing production. Furthermore, China's special institutional circumstance enables its government to organize various actors to form a growth alliance, which will act together in the production of post-suburbanization space. [ABSTRACT FROM AUTHOR]

Knowledge of human gingival cell responses to dental monomers is critical for the development of new dental materials. Testing standards have been developed to provide guidelines to evaluate biological functionality of dental materials and devices. However, one shortcoming of the traditional testing platforms is that they do not recapitulate the multi-layered configuration of gingiva, and thus cannot evaluate the layer-specific cellular responses. An oral mucosa-chip with two cell layers was previously developed as an alternative platform to assess the oral mucosa responses to dental biomaterials. The mucosa-chip consists of an apical keratinocyte layer attached to a fibroblast-embedded collagen hydrogel through interconnecting pores in a three-microchannel network. Here, cell responses in the mucosa-chip were evaluated against 2-hydroxyethyl methacrylate (HEMA), a common monomer used in restorative and aesthetic dentistry. The response of mucosal cell viability was evaluated by exposing the chip to HEMA of concentrations ranging from 1.56 to 25 mM and compared to cells in conventional well-plate monoculture. The co-cultured cells were then stained and imaged with epifluorescence and confocal microscopy to determine the layer-specific responses to the treatment. Mucosa-chips were demonstrated to be more sensitive to assess HEMA-altered cell viability than well-plate cultures, especially at lower doses (1.56 and 6.25 mM). The findings suggest that the mucosa-chip is a promising alternative to traditional platforms or assays to test a variety of biomaterials by offering a multi-layered tissue geometry, accessible layer-specific information, and higher sensitivity in detecting cellular responses. [ABSTRACT FROM AUTHOR]

Acyl-coenzyme A oxidases 1 (ACOX1) is the first rate-limiting enzyme responsible for peroxisomal β-oxidation. In the present study, two mRNA variants, ACOX1a and ACOX1b, transcribed from a single gene, were for the first time isolated and characterized from grass carp Ctenopharyngodon idella, both encoding putative peptides of 660 amino acids. Analysis of the exon-intron structures clarified that grass carp ACOX1a and ACOX1b comprise 14 coding exons and correspond to 3a and 3b isoforms of exon 3 splicing variants. Both ACOX1a and ACOX1b mRNAs were expressed in a wide range of tissues, but the abundance of each ACOX1 mRNA showed the tissue-dependent expression patterns. Time-course analysis of ACOX1 expressions indicated that the level of ACOX1a mRNA reached an almost maximal level at day 2, while that of ACOX1b mRNA reached an almost maximal level at day 8 during grass carp primary preadipocyte differentiation. In fasting-induced adipocyte lipolysis, only ACOX1a showed a significant increase in adipocyte, indicating that two ACOX1 isoforms may serve somewhat different roles in the peroxisomal β-oxidation. These results suggested that grass carp ACOX1a and ACOX1b were differently modulated by fasting in adipocyte. In addition, we found that mitochondrial β-oxidation might dominate at the early stage of fasting in adipocytes, indicating that mitochondria and peroxisomes might possess different capacities in fasting-induced adipocytes fatty acid oxidation. [ABSTRACT FROM AUTHOR]

The emergence of rapid transit, primarily represented by high-speed railway (HSR), while reshaping the regional traffic patterns, leads to the reconstruction and redistribution of population and industry. This leads to either shrinkage or expansion of urban scale. However, research on the influence mechanisms of the urban scale has mostly concentrated on historical, economic and social factors. The influence of traffic factors is rarely mentioned in current research. Therefore, this study examines Northeast China, where the change in urban scale is most significant, to discuss the spatial impact of high-speed railway on the urban scale. This is of great significance in terms of enriching current understanding of the factors affecting the urban scale. The results included the following: 1) The high-speed railway produced considerable space-time convergence effects, however, simultaneously aggravated the imbalance in traffic development in Northeast China. The increase in accessibility presents attenuation characteristics from the high-speed railway. Additionally, the high-speed railway has changed the mode of cooperation between cities in the provinces, inter-regional and inter-provincial cooperation models gradually become popular. 2) The change rate of accessibility and the urban scale present significant spatial coupling phenomena, with the change rate of the Harbin-Dalian trunk lines and its surroundings being more significant. 3) There are predominantly four modes of the influence of high-speed railway on the urban scale, which make difference city present expansion or shrinkage. [ABSTRACT FROM AUTHOR]

Background: Common causes of complications of laparoscopic pyeloplasty in children include anastomotic stricture, poor drainage due to high ureteropelvic anastomosis, and torsion of ureter. Herewith, we described our modified technique of paraumbilical three-port laparoscopic dismembered pyeloplasty (PTLDP) to minimize these complications.Patients and Methods: Data from 62 patients (age: 1-180 months, median: 12 months) with ureteropelvic junction obstruction (UPJO) who underwent pyeloplasty using our modified technique of PTLDP between February 2014 and September 2014 at our institution were reviewed. The key steps of our modified method involve identifying the lowest point of the renal pelvis and the lateral aspect of the ureter to guarantee a low pelviureteric and correct orientation anastomosis, and using a 4-0 silk for assistant suturing to avoid crushing of the anastomotic tissue.Results: All surgeries were successfully completed without conversion. Three patients required an accessory port for the anastomosis. All the patients achieved complete clinical or radiologic resolution after the operation. The mean operative time was 103.4 min, and mean estimated blood loss was 14.4 mL. Mean postoperative differential function of affected kidney was 43.0 ± 16.3 % (range 24-100 %), increased from 39.7 ± 18.0 % (range 18-100 %), preoperatively (p < 0.001). The success rate was 100 % at a mean follow-up of 18.3 ± 2.9 (range 13-25) months.Conclusions: Our modified technique of PTLDP is safe and feasible and to allow high success rate for the treatment of pelviureteric junction obstruction in children. [ABSTRACT FROM AUTHOR]

Rural development inequality is an important practical issue during the course of full establishment of a 'moderately well-off society' in modern China, and the objective understanding and evaluation of the status and regional inequality of rural development can provide scientific basis for 'building a new countryside' and coordination development of rural-urban regions. Based on the county-level data of 2000, 2005 and 2009, this paper examines the rural development inequality of Jilin Province in Northeast China by establishing a rural development index. The spatio-temporal dynamic patterns and domain factors are discussed by using the method of exploratory spatial data analysis and multi-regression model. The results are shown as follows. Firstly, most of the counties were in lower development level, which accounted for 58.3%, 62.5% and 66.7% of the total counties in 2000, 2005 and 2009, respectively. The characteristics of spatial inequality were very obvious at county level. For example, rural development level of Changchun Proper and the proper of seven prefecture-level cities were much higher than that of the surrounding regions. The counties in the eastern and northern Jilin Province were the lowest regions of rural development level, while the middle counties were the rapid growth areas in rural economy. Secondly, Moran's I of rural development index (RDI) was 0.01, −0.16 and −0.06 in 2000, 2005 and 2009, respectively, which indicated that spatial agglomeration of RDI was not obvious in Jilin Province, and took on the characteristic of random distribution. The counties of both the units and its adjacent units have higher development level (HH) were transferred from the western areas to the eastern areas, while the countries of both the units and its adjacent units have lower development level (LL) were diffused from the eastern to middle and western Jilin Province. Finally, the result of multi-regression analysis showed that the improvement of agricultural production condition, development of agricultural economics and the adjustment of industrial structure were the domain factors affecting rural development inequality of Jilin Province in the later ten years. [ABSTRACT FROM AUTHOR]

A hemopoietin with the ability to accelerate both platelet and granulocyte recovery after intensive chemotherapy would have great clinical utility. The recombinant fusion protein composed of human granulocyte-macrophage colony-stimulating factor and interleukin-3 (PIXY321), showed some promise in early adult trials. However, studies for pediatric patients are limited, and there are no systematic data on the pharmacokinetics of PIXY321 given over prolonged periods at current dosage levels. Purpose: To determine the safety, clinical effects and plasma concentrations of increasing doses of PIXY321 in children treated with myelosuppressive chemotherapy. Methods: A total of 39 children with relapsed or high-risk solid tumors were enrolled in this phase I/II study. PIXY321 was administered once or twice daily by subcutaneous injection in total doses of 500 to 1000 μg/m2 per day for 14 days after each course of chemotherapy with ifosfamide, carboplatin, and etoposide (ICE). Pharmacokinetic studies were performed on day 1 of the first course in 33 patients and repeated on day 14 in 13 patients (once-daily schedule only). Results: Although mild local skin reactions and fever were frequent, no dose-limiting toxicity was identified at the maximum dose studied (1000 μg/m2 per day). There were no statistically significant differences in chemotherapy-induced hematologic toxicity with increasing doses of PIXY321 or with twice-daily vs once-daily dosing. On day 1, the median PIXY321 clearance was 657 ml/min per m2 (range 77–1804 ml/min per m2) and the median half-life was 3.7 h (range 2.1–20.8 h). On day 14, clearance increased in all patients studied (median increase 63%), with a corresponding decrease in the median 12-h concentration (from 1.2 to 0.25 ng/ml). Maximum concentrations were <1 ng/ml in 81% of patients, and only two patients had maximum plasma concentrations equivalent to those required for consistent activity in vitro. Conclusions: The recombinant fusion protein PIXY321 proved safe in children treated with myelosuppressive ICE chemotherapy but had no demonstrable clinical benefits. The pharmacokinetic studies suggest that the observed lack of hematologic benefit may be explained by low plasma concentrations resulting from increased clearance with prolonged administration. Moreover, the significant increase in PIXY321 systemic clearance in the absence of increased circulating myeloid cells suggests that the upregulation of either extravascular compartment hematopoietic progenitor cells or nonhematopoietic cells may play an important role in controlling circulating concentrations of this unique cytokine. These findings highlight the importance of a thorough assessment of the systemic disposition of cytokines when determining the dose and schedule necessary to achieve clinical activity in patients. [ABSTRACT FROM AUTHOR]