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Background: Colorectal cancer (CRC) incidence and mortality rates have been increasing among young patients (YP), for uncertain reasons. It is unclear whether YP have a distinct tumor biology or merit a different treatment approach to older patients (OP). Methods: We reviewed prospectively collected data from consecutive patients with metastatic CRC (MCRC) enrolled in the multi-site Treatment of Recurrent and Advanced Colorectal Cancer (TRACC) Australian registry. Clinicopathological features, treatment and survival outcomes were compared between YP (

Path planning is to calculate a path for users from the departure location to the destination by considering some conditions, such as travel distance, time, or safety. Although users are generally rigid-bodies with certain dimensions (e.g., cars, wheelchair), they are abstracted as a 0D point in current path planning. Such practice can simplify and accelerate path planning in environments where the spaces are large enough to ignore the users’ dimensions. However, in many cases, the dimension of a user for path planning cannot be ignored, especially in some spaces where safety is critical, such as garage entrances. To help rigid-bodies safely enter into entrances, this paper presents a theoretical path computation model, in which users are rectangular rigid-bodies (RRB). This theoretical model can help the RRB-like users (e.g., robots, unmanned vehicles) to determine if an entrance is passable and further how to enter an entrance safely.

We resolve a previously unrecognized shallow subducting seamount from a re-processed multichannel seismic profile crossing the 1994 Mw 7.8 Java tsunami earthquake rupture area. Seamount subduction occurs where the overriding plate experiences uplift by lateral shortening and vertical thickening. Pronounced back-thrusting at the landward slope of the forearc high and the formation of splay faults branching off the landward flank of the subducting seamount are observed. The location of the seamount in relation to the 1994 earthquake hypocentre and its co-seismic slip model suggests that the seamount acted as a seismic barrier to the up-dip co-seismic rupture propagation of this moderate-size earthquake.

The China-Europe Railway Express (CER-Express), not only promoted the cooperation between countries and regions across Asia and Europe but also gave rise to remarkable changes in landcover and had a profound effect on the natural environment along the railway in recent years. Effective ways to monitor and assess ecological changes are urgently needed to ensure sustainable development of CER-Express. There are very few existing environmental monitoring studies focusing on the area along the CERExpress. In this paper, we present a study of environmental degradation, which occurred during the construction and operation of CER-Express from 2010 to 2018, based on a comprehensive evaluation index (CEI), which takes three environmental indicators into account and provides a timely and reliable evaluation of environmental changes at large scales. In addition, the environment conditions of the regions and countries along the CER-Express have been quantified and comparatively studied at different scales over different periods, using histograms of mean CEI values. Furthermore, specific causes of environmental degradation in the rail-intensive countries and small-area countries along the railway are discussed. Our results show that the environmental degradation can be detected in most of the rail-intensive countries, such as Germany, Poland, Austria, and Czech Republic along the railway. Therefore, to ensure sustainability of the CER-Express, environmental protection along the railway should be paid more attention to and a reasonable arrangement for the exploitation of CER-Express devised.

Investigating groundwater residence time and recharge sources is crucial for water resource management in the alluvium aquifers of arid basins. Environmental tracers (chlorofluorocarbons, 3H, 14C, δ2H, δ18O) and groundwater hydrochemical components are used for assessing groundwater mean residence times (MRTs) and aquifer recharge in fault-influenced hydraulic drop alluvium aquifers in the Manas River basin (China). Aquifers under the Manas River upstream (south of the fault) contains very high 3H activity (41.1–60 TU), implying water recharge affected by the nuclear bomb tests of the 1960s. Carbon-14 groundwater age correlates positively with distance from mountain area (3000–5000 years in the midstream to > 7000 years in the downstream) and groundwater depth, but correlates negatively to a decrease in 3H activity (1.1 TU) and more negative δ18O values. This phenomenon reveals that the source of the deeper groundwater in the semi-confined aquifer is paleo-meteoric recharge. Special attention has been paid to the estimation of MRTs using CFCs and 3H by an exponential piston flow model. The results show that MRTs vary from 19 to 101 years by CFCs and from 19 to 158 years by 3H. MRTs estimated from 3H are much longer than those from CFCs, probably due to the different time lag of liquid (3H) and gas-phase CFCs through the unsaturated zone. The MRTs estimated by CFCs show good correlations with pH and the concentrations of SiO2 and SO42-, which can provide a possible approach to estimate first-order proxies of MRTs for groundwater age. The young water fractions are investigated by the CFC binary mixing method in the south and north of the fault. Relatively modern recharge is found in the south of the fault with young (post-1940) water fractions of 87 %–100 %, whereas in the north of the fault the young water fractions vary from 12 % to 91 %. This study shows that the combination of CFCs and 3H residence time tracers can help in analysing the groundwater MRTs and the recharge sources for the different mixing end-members.

High-entropy ceramics (HECs) have rapidly expanded from high-entropy oxides to high-entropy ultrahigh temperature ceramics/coatings and have drawn extensive attention in the field of ceramics. In addition, high-entropy thermoelectric materials focus on the topic of energy, which is another major driving force to accelerate the development of HECs. In this review, the recent progress on the design and synthesis of chemically complex ceramics is summarized. The fundamental understanding of configurational entropy, phase stability, and formation criterion of HECs are discussed. Critical comments on the compositionally complex ceramics and mixed-valence complex ceramics are presented. The synthesis methods of HECs are summarized, and reactive flash sintering is highlighted as a new strategy to synthesize HECs. The new design ideas and synthesis methods can provide more opportunities to develop high-performance HECs to meet the requirements of cutting-edge applications.

Although channelized urban streams provide aesthetic and economic value, they reduce biodiversity and alter the habitats of aquatic organisms. Spur dikes not only prevent the erosion of riverbanks, but also generally improve aquatic habitats. River 2D is widely used to analyze the aquatic habitats. However, the model often faces a challenge of lacking sediment and riverbed evolution module, which is difficult to predict the change of aquatic habitats. In this study, a depth-averaged habitat model, which couples a two-dimensional water-sediment shallow water model with an Instream Flow Incremental Methodology (IFIM), was provided to evaluate the impact of spur dikes on the improvement of aquatic habitats in the Jinjiang Stream in Chengdu, China.The potential value of aquatic habitats was quantitatively evaluated by a weighted useable area (WUA). Under different spur dike scenarios, the WUA is greater than under natural conditions, that is, the construction of spur dikes is beneficial for improving the habitat of aquatic organisms in urban rivers. In addition, further analysis from the simulation results shows that the three-spur dike scenario with a flow of 40 m³/s represents the best layout of spur dikes. Our study indicates that adjusting the spur dike layout is an effective instrument to enhance aquatic habitats, and can provide a certain reference for water ecological restoration and river management.

Abstract The water environmental capacity (WEC) is an effective tool to solve the water pollution problem and achieve optimal water quality management. However, in a seasonal river, some important input data such as discharge and pollution concentration from river tributaries and lateral inflows are rarely available. This makes WEC calculating more challenging. In this study, the water environment system model that integrates hydrological process in the watershed and hydrodynamic water quality process in the river is proposed to compensate for the lack of data. Taking the Guishui River basin as an example, the SWAT and HEC‐RAS models were selected. The discharge and pollution concentration of ungauged tributary output from SWAT are used as the inputs of the water quality model HEC‐RAS. In addition, static and dynamic design hydrological conditions were used to calculate WEC. The model results basically agree with the observed data, and it was verified that the integrated water environment system model can be used to calculate WEC. The pollutant reduction targets of the tributaries under the monthly line‐fitting method are less than that under static hydrological condition. The obtained results could be used to support water pollution control and water quality management in the Guishui River basin.

The spin-structure functions g1 and g2, and the spin-dependent partial cross-section σTT have been extracted from the polarized cross-sections differences, Δσ∥(ν,Q2) and Δσ⊥(ν,Q2) measured for the He3→(e→,e′)X reaction, in the E97-110 experiment at Jefferson Lab. Polarized electrons with energies from 1.147 to 4.404 GeV were scattered at angles of 6∘ and 9∘ from a longitudinally or transversely polarized 3He target. The data cover the kinematic regions of the quasi-elastic, resonance production and beyond. From the extracted spin-structure functions, the first moments Γ1‾(Q2), Γ2(Q2) and ITT(Q2) are evaluated with high precision for the neutron in the Q2 range from 0.035 to 0.24GeV2. The comparison of the data and the chiral effective field theory predictions reveals the importance of proper treatment of the Δ degree of freedom for spin observables.

Dust pollution is serious in many areas of China. It is of great significance to estimate chlorophyll content of vegetation accurately by hyperspectral remote sensing for assessing the vegetation growth status and monitoring the ecological environment in dusty areas. By using selected vegetation indices including Medium Resolution Imaging Spectrometer Terrestrial Chlorophyll Index (MTCI) ，Double Difference Index (DD) and Red Edge Position Index (REP), chlorophyll inversion models were built to study the accuracy of hyperspectral inversion of chlorophyll content based on a laboratory experiment. The results show that: (1) REP exponential model has the most stable accuracy for inversion of chlorophyll content in dusty environment. When dustfall amount is less than 80 g/m2, the inversion accuracy based on REP is stable with the variation of dustfall amount. When dustfall amount is greater than 80 g/m2, the inversion accuracy is slightly fluctuation. (2) Inversion accuracy of DD is worst among three models. (3) MTCI logarithm model has high inversion accuracy when dustfall amount is less than 80 g/m2; When dustfall amount is greater than 80 g/m2, inversion accuracy decreases regularly and inversion accuracy of modified MTCI (mMTCI) increases significantly. The results provide experimental basis and theoretical reference for hyperspectral remote sensing inversion of chlorophyll content.

Soil and water losses in agriculture are major environmental problems worldwide, especially on the Loess Plateau, China. Summer fallow management may help to control soil erosion and conserve water. This study investigated the effects of wheat stubble on runoff, infiltration, and soil loss in laboratory plots under simulated rainfall. The treatments comprised wheat stubble cover (WS) and traditional plowing (TP) in runoff plots (4.0 m × 1.0 m) with three slope gradients (5, 10, and 15°) under simulated rainfall at 80 mm h−1 for 1 h. The runoff volume from WS plots was significantly less than that from TP. The runoff reduction with WS ranged from 91.92 to 92.83 % compared with TP. The runoff rates varied with the runoff volume in the same manner. The infiltration amount was higher with WS (94.8–96.2 % of rainwater infiltrated) than TP (35.4–57.1 %). The sediment concentration was significantly lower with WS than TP. Compared with TP (304.31–731.23 g m−2), the sediment losses were reduced dramatically in WS (2.41–3.78 g m−2) and the sediment loss slightly increased with slope; however, it was greatly increased as slope increased in TP. These results revealed that the stubble cover was the main factor reducing runoff and sediment losses and improving infiltration and that stubble showed a great potential to control erosion and conserve soil and water resources during the summer fallow period in the Loess Plateau region.

With the development of economy, global demand for steel has accelerated since 2000, and thus mining activities of iron ore have become intensive accordingly. An ultra-low-grade iron has been extracted by open-pit mining and processed massively since 2001 in Kuancheng County, Hebei Province. There are large-scale stopes and tailings ponds in this area. It is important to extract their spatial distribution information for environmental protection and disaster prevention. A remote sensing method of extracting stopes and tailings ponds is studied based on spectral characteristics by use of Landsat 8 OLI imagery and ground spectral data. The overall accuracy of extraction is 95.06 %. In addition, tailings ponds are distinguished from stopes based on thermal characteristics by use of temperature image. The results could provide decision support for environmental protection, disaster prevention, and ecological restoration in the ultra-low-grade iron ore mining area.

The result of the comparative study on monitoring of culture heritage between China and the world shows that it is imperative for China to carry out Large Ruins monitoring. Some key questions that this paper will consider are: What should be monitored at Large Ruins? How do we build monitoring systems? To answer these questions, this paper, will use the Old Summer Palace ruins as an example and look at its design of monitoring systems and upcoming monitoring activities of its ruins. It will also consider how the Old Summer Palace makes a preliminary attempt to build a monitoring system for one of China’s “Large Ruins” by exploring the aspects of monitoring necessity, identification of monitoring targets, and building of monitoring system of the European-style Palace of the Old Summer Palace.

Three-dimensional numerical simulations of natural convection heat transfer of Al2O3-water nanofluid in a differentially-heated, cubic enclosure is performed considering nanoparticles shape. The effects of nanoparticles shape, nanoparticles volume fraction and Rayleigh number on natural convection heat transfer of Al2O3-water nanofluid are analysed. The results show that the thermal conductivity of nanofluid increases with the addition of Al2O3 rod-shaped nanoparticles, and the increasing degree of viscosity of nanofluid is higher than that of thermal conductivity. When Al2O3 spherical nanoparticles are dispersed in water, the strength of flow and heat transfer increases with increasing nanoparticles volume fraction. The average Nusselt number increases with the increase of nanoparticles volume fraction at Ra=103 for Al2O3-water nanofluid with different nanoparticles shape. When Ra≥104, the average Nusselt number decreases with the increasing volume fraction of Al2O3 rod-shaped nanoparticles, and the average Nusselt number increases with the increase of spherical nanoparticles volume fraction. The heat transfer rate increases with increasing Rayleigh number for nanofluid with different nanoparticles shape.

[Fe/Fe4N]N multilayers with high saturation magnetization were prepared on MgO(200) substrate, by the DC reactive magnetron sputtering and then annealed at higher temperature. Their structural and magnetic properties were investigated. Epitaxial growth of α-Fe and γ’-Fe4N were demonstrated on MgO, and then excellent [Fe/Fe4N]N was obtained. Though the saturation magnetizations of the as-deposited [Fe/Fe4N]N are slightly below the average value of those of α-Fe and γ’-Fe4N, the saturation magnetization of the annealed [Fe(3.04 nm)/Fe4N(3.04 nm)]5 increases up to 1850 emu/cc, 32 % larger than that of α-Fe film. N atom diffusion from the γ’-Fe4N to the α-Fe layer at high temperature greatly improves the saturation magnetization.

We compare genome sequences of three closely related soft-rot pathogens that vary in host range and geographical distribution to identify genetic differences that could account for lifestyle differences. The isolates compared, Pectobacterium atrosepticum SCRI1043, P. carotovorum WPP14, and P. brasiliensis 1692, represent diverse lineages of the genus. P. carotovorum and P. brasiliensis genome contigs, generated by 454 pyrosequencing ordered by reference to the previously published complete circular chromosome of P. atrosepticum genome and each other, account for 96% of the predicted genome size. Orthologous proteins encoded by P. carotovorum and P. brasiliensis are approximately 95% identical to each other and 92% identical to P. atrosepticum. Multiple alignment using Mauve identified a core genome of 3.9 Mb conserved among these Pectobacterium spp. Each core genome is interrupted at many points by species-specific insertions or deletions (indels) that account for approximately 0.9 to 1.1 Mb. We demonstrate that the presence of a hrpK-like type III secretion system-dependent effector protein in P. carotovorum and P. brasiliensis and its absence from P. atrosepticum is insufficient to explain variability in their response to infection in a plant. Additional genes that vary among these species include those encoding peptide toxin production, enzyme production, secretion proteins, and antibiotic production, as well as differences in more general aspects of gene regulation and metabolism that may be relevant to pathogenicity.