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In this work, the texture evolution, mechanical properties, and formability of cold-rolled lightweight steel annealed at 500, 600, 700, and 800 °C for 30 min were investigated. The phases in the annealed specimens mainly included ferrite, austenite, and martensite. The retained austenite showed a trend of increasing and then decreasing with the increase in annealing temperature. At the annealing temperature of 700 °C, the retained austenite content reached the maximum value of 53.0%, resulting in a large amount of martensitic TRIP effect during the subsequent deformation. So the steel obtained the optimal mechanical properties with the ultimate tensile strength of 1613 MPa, ultimate elongation of 30.2%, and largest product of strength and ductility of 48.7GPa%. In addition, the annealing temperature of 700 °C was conducive to the stamping texture of {111} < 110> orientation, as well as higher strength, and the plastic strain ratio (r), the strain hardening index (n), and the flexural strength ratio (ReL/Rm) were 1.25, 0.55, and 0.41, respectively, the material obtained excellent formability. [ABSTRACT FROM AUTHOR]

Hard limestone substrates, which are extensively distributed, are believed to exacerbate drought and increase the difficulty of restoration in vulnerable karst regions. Fissures in such substrates may alleviate the negative effect of drought on plants, but the underlying mechanisms remain poorly understood. In a two-way factorial block design, the growth and photosynthesis of 2-year-old Phoebe zhennan seedlings were investigated in two water availabilities (high versus low) and three stimulated fissure habitat groups (soil, soil-filled fissure and non-soil-filled fissure). Moreover, the fissure treatments included both small and big fissures. Compared to the soil group, the non-soil-filled fissure group had decreased the total biomass, root biomass, total root length, and the root length of fine roots in the soil layer at both water availabilities, but increased net photosynthetic rate (Pn) and retained stable water use efficiency (WUE) at low water availability. However, there were no significant differences between the soil-filled fissure group and soil group in the biomass accumulation and allocation as well as Pn. Nevertheless, the SF group decreased the root distribution in total and in the soil layer, and also increased WUE at low water availability. Across all treatments, fissure size had no effect on plant growth or photosynthesis. Karst fissures filled with soil can alleviate drought impacts on plant root growth, which involves adjusting root distribution strategies and increasing water use efficiency. These results suggest that rock fissures can be involved in long-term plant responses to drought stress and vegetation restoration in rocky mountain environments under global climate change. [ABSTRACT FROM AUTHOR]

Background and aims: Soil heterogeneity can be caused by plant-soil feedback (PSF), but little is known about how this affects plant growth and the distribution of roots. Moreover, as invasive and native plant species frequently differ in PSF and root-foraging ability, they may differ in their responses to PSF-mediated soil heterogeneity. Methods: We first conditioned soils by 16 plant species (eight confamilial pairs of invasive alien and native species). Then, we grew each species in a homogeneous treatment with unconditioned soil and in three heterogeneous treatments with four patches. In the home-soil treatment, we filled two patches with unconditioned soil and two with soil conditioned by the target species. In the foreign-soil treatment, we filled two patches with unconditioned soil and two with soil conditioned by the other species in a pair. In the home-and-foreign-soil treatment, we filled two patches with home soil and two with foreign soil. Results: Compared to the homogeneous unconditioned soil treatment, PSF negatively affected plant growth. In the heterogeneous treatment with control- and home-soil patches, biomass was reduced more strongly for the invasive species than for the native species. In the heterogeneous treatment with both home- and foreign-soil patches, root biomass of the invasive species was greater in the foreign-soil than in the home-soil patches, whereas the reverse was true for natives. Conclusion: Although invasive species suffered more from conspecific PSF, root foraging allowed them to avoid home soil. In the long term, this could help invasive species gain a competitive advantage over natives. [ABSTRACT FROM AUTHOR]

Background and aims: Heavy metal (especially for potentially toxic element) contamination in soil has frequently been associated with plant invasion. However, the mechanisms underpinning plant invasion under potentially toxic element contamination remain unclear. Here we studied how differences in clonal traits of invasive and native plants affect their response strategies to stresses of potentially toxic element contamination. Methods: We manipulated clonal integration of two pairs (Alternanthera philoxeroides - A. sessilis, and Sphagneticola trilobata - S. calendulacea) of congeneric invasive and native plants by either severing stolons between ramet pair or not severing, and grew them in soils contaminated by three levels of Cd and three levels of Pb. Results: Our results show that the combination of Cd and Pb contamination decreased plant growth of recipient ramets of Alternanthera species. Under Pb stress, invasive S. trilobata is Pb-hyperaccumulation and benefits more from clonal integration than native S. calendulacea. Similarly, under Cd stress, invasive A. philoxeroides shows higher Cd risk sharing and benefits more from clonal integration than native A. sessilis. In contrast, clonal integration decreased the performance of A. sessilis under high Cd stress. Conclusion: These results suggest that invasive species such as A. philoxeroides and S. trilobata are able to alleviate the toxic effects of Cd and Pb co-contamination via clonal integration, thus becoming more invasive in contaminated environments with potentially toxic elements. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the correlation between tibial tuberosity-trochlear groove distance (TT-TG) and body height or knee size, and to find height-related pathologic thresholds of increased TT-TG.Methods: One-hundred and fifty-three patients with recurrent patellar instability and 151 controls were included. The TT-TG was measured on axial computed tomography (CT) images. Femora width and tibial width were selected to represent knee size. The correlation of TT-TG and gender, body height, femora width, and tibial width was evaluated. The height-related pathologic threshold of increased TT-TG was produced according to Dejour's method. To combine TT-TG with body height and knee size, three new indexes were introduced, ratio of TT-TG to body height (RTH), ratio of TT-TG to femoral width (RTF), and ratio of TT-TG to tibial width (RTT). The ability to predict patellar instability was assessed by the receiver-operating characteristic (ROC) curve, odds ratios (ORs), sensitivity, and specificity.Results: In patients with patellar instability, TT-TG showed significantly correlation with patient height, femoral width, and tibial width respectively (range r = 0.266-0.283). This correlation was not found in the control group. The pathologic threshold of TT-TG was 18 mm in patients < 169 cm (53%), and the mean TT-TG was 21 mm in patients ≥ 169 cm (54%). There was significant difference in RTH, RTF, and RTT between the two groups. RTH, RTF and RTT have similar large area under the curve (AUC) with TT-TG.Conclusions: TT-TG showed significant correlation with body height and knee size, respectively. The pathologic threshold of increased TT-TG was suggested to be 21 mm for patients [Formula: see text] 169 cm and 18 mm for patients [Formula: see text] 169 cm. Body height-related pathologic threshold provided a supplement for indications of tibial tuberosity medialization.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]

Xiangshan volcanic-related uranium ore field, as the historic largest uranium producer in China, is characterized by a large volcanic-intrusive complex and a number of uranium deposits. In most of the deposits, various types of dikes are spatially associated with the uranium ore bodies, although there have been no systematic attempts to integrate the geochronology and petrogenesis of these dykes and their link with uranium mineralization. In this study, whole-rock major and trace elements, zircon U–Pb dating and zircon Hf–O isotopic analysis were carried out on the Xiagnshan felsic-intermediate dikes, including granitic porphyry, quartz monzonitic porphyry and dioritic porphyry. These felsic-intermediate dikes have the similar geochemical characteristics with the major ore-hosting volcanic rocks, such as enrichment in large lithophile elements (i.e., Rb and Th) and some high-field strength elements (i.e., Zr, Y), but relative depletion in Sr, Ba, P and Ti. These dikes also exhibit zircon εHf(t) values concentrating from -9 to -4 and zircon δ18O values ranging from 7.6 to 10.0 ‰. Geochemical and isotopic data suggest that these dikes were predominantly derived from partial melting of crustal materials and possibly mingled with different proportions of mantle-derived materials during the formation of melts. SIMS and SHRIMP U–Pb dating of zircon grains from these felsic-intermediate dikes yield high-precision ages ranging from 136 to 131 Ma. Combined with previously reported age data indicates a rapid and concentrated dike emplacement event, although a few mafic-felsic dikes were sporadically emplaced at 126 -122 Ma. Such a relatively concentrated dike emplacement in the Early Cretaceous were most likely caused by the back-arc extension or intra-arc rift due to progressive rollback of the Paleo-Pacific Plate. Previous metallogenetic studies supported that the late-stage dikes at Xiangshan were temporally and spatially closely related to uranium mineralization. However, our new geochronological data and field observations indicate that the two episodes of uranium mineralization were not synchronous with the majority of dikes intrusions, indicating that they probably have no direct relationship in origin and that spatial coexistence were more likely due to multistage activities of faults. Rather, these dikes might act as a relatively reduced environment, and thus could facilitate the precipitation of uranium. In addition, all of these dikes can be considered favorable prospecting indicators in the Xiangshan ore field. [ABSTRACT FROM AUTHOR]

A recently reported four-parameter cohesive zone model (CZM) has applications in dynamic fracture such as the drop-weight tear test simulation. In this paper, the CZM method is utilized to analyze the global response of the dynamic fracture problems. And the two key CZM parameters, maximum traction and cohesive energy, are determined from the nominal stress-strain (SS) curve by considering the damage scalar and a simulation of the tensile test, respectively. The other two parameters, S0 and Sm, are related to the shapes of the traction-separation law (TSL), which characterize its stiffness and softening shape, respectively. The influences of TSL's shape on the global response such as the nominal SS curves and the load-displacement curves are analyzed by the finite element method. Evident (TSL's) shape effects are found in the case of high-speed dynamic fracture of pipeline steels, which is completely different from quasi-static models. [ABSTRACT FROM AUTHOR]

In the large majority of papers utilizing the Gurtin-Murdoch (G-M) model of a material surface, the complete model is avoided in favor of various modified versions often because they lead to simpler representations of the corresponding stress boundary condition. We propose in this paper an integral-type stress boundary condition for the plane deformations of a bulk-interface composite system which allows for an equally simple implementation of the complete G-M model. Since the mechanical behavior of such composite systems is often analyzed using complex variable methods, we formulate our ideas accordingly, in this context. Remarkably, in contrast to what is often believed to be the case, we find that boundary value problems based on our formulation of the stress boundary condition offer no added difficulty when utilizing the complete G-M model versus its various simplified counterparts. This new representation of the stress boundary condition is concise in form and will prove to be extremely useful in, for example, the calculation of the elastic field in the vicinity of nano-inhomogeneities of irregular shape. [ABSTRACT FROM AUTHOR]

Purposes: This study analyzed morphological differences in the resected proximal tibial surfaces of Chinese males and females undergoing total knee arthroplasty (TKA) and compared the measurements with the dimensions of five currently used tibial implants. Methods: The mediolateral (ML), middle anteroposterior (AP), medial anteroposterior (MAP), and lateral anteroposterior (LAP) dimensions of the resected tibial surfaces of 976 Chinese TKA knees (177 male, 799 female) were measured. The ML/AP ratio of every knee was calculated. These morphological data were compared with the dimensions of five currently used tibial implants. Results: The ML, AP, MAP, and LAP dimensions of the resected proximal tibias showed significant differences according to gender. Compared with currently used tibial implants, the smaller implants showed tibial ML undersizing and the larger implants showed tibial ML overhang. The ML/AP aspect ratio progressively decreased with increasing AP dimension in the resected proximal tibias, which contrasts with the relatively constant or increased (NexGen) aspect ratio in currently used tibial implants. Males showed a higher ML/AP aspect ratio than females for a given AP dimension. This indicates that for an implant with a given AP dimension, the tibial ML dimension tends to be undersized in males and to overhang in females. Conclusion: The results of this study may provide fundamental data for designing suitable tibial implants for use in the Chinese population, especially for design of gender-specific prostheses. Level of evidence: II. [ABSTRACT FROM AUTHOR]

Laboratory experiments were conducted to investigate the transformation and performance of a granular sequence batch reactor (SBR) under the conventional organic loading rate (OLR) condition. Aerobic granules were successfully cultivated in a SBR by means of alternative feeding load combined with reducing settling time after 60 d operational period. Subsequently, the black fungal granules were presented in reactor because of the filamentous overgrowth on the surface of aerobic granules. A small amount of fungal granules had no effect on the performance of granular SBR. Aerobic granules completely vanished and fungal granules eventually became the dominant species in subsequent 90 d operation after granulation. The three-dimensional excitation emission matrix (EEM) spectra result shows that the extracellular polymeric substances (EPS) component in both granules has no much difference, whereas the content of EPS in fungal granules is higher than that in bacterial granules. Due to their low bioactivity, the chemical oxidation demand (COD) and NH-N removal efficiencies gradually decrease from 90.4%-96.5% and 99.5% to 71.8% and 32.9% respectively while the fungal granules become dominant in the SBR. [ABSTRACT FROM AUTHOR]

Incidence and intensity of bark stripping of trees by ungulates was investigated at no bamboo ( Fargesia nitida (Mitford) Keng f. ex Yi) (B-) site and understory bamboo dominant (B+) site of a subalpine Abies faxoniana Rehder & E. H. Wilson forest, southwest China. The percentage of damaged trees in B-site was higher than in B+ site. Bark stripping obviously occurred more frequently on Abies faxoniana compared to other tree species. Appearance of stripped bark and dead stems of the trees in different size-classes of A. faxoniana strongly depended on the density of dwarf bamboo at the site, and also on the size and bark structure of the trees, with highest damage rates occurring on the smaller DBH classes (10-40 cm) in B-site. The bark stripping intensity of A. faxoniana decreased significantly with higher density and coverage of F. nitida around damaged trees. Therefore, there is an indirect negative effect of the distribution of dwarf bamboo, F. nitida, on bark stripping of tree species. We suggest the indirect effects of dwarf bamboo species should be taken into account while considering the succession and regeneration of natural forests. [ABSTRACT FROM AUTHOR]

Reproductive behaviour of clonal plants might change in contrasting habitats. In field and simulated experiments, we studied the relative importance of sexual reproduction and clonal propagation in rhizomatous herb, Iris japonica Thunb. in two forest habitats (BF, bamboo forest and OAFE, open area of forest edge), and effects of population origin (BF vs. OAFE) and environmental effects (shading) on sexual vs. clonal reproduction. In field experiment, the relative importance of reproduction in I. japonica populations was different in two habitats, which showed predominantly sexual reproduction in OAFE and clonal propagation in BF. In simulated experiment, the effect of population origin and light treatment (shading) was significant for reproduction of I. japonica. Clonal propagation was only influenced by population origin, and sexual reproduction was determined both by population origin and light treatment. A trade-off between two reproductive modes exhibited in both experiments. The trade-offs was more obvious in OAFE than in BF because sexual reproduction, resource and inter-specific competition obviously lacked in BF. The results indicated that the selective forces shaping reproduction of I. japonica in contrasting habitats might demonstrate pronounce adaptive population differentiation among forest habitats. Thus, I. japonica populations formed local differentiation by adaptation of reproduction to local heterogeneous forest habitats. [ABSTRACT FROM AUTHOR]

This study evaluated the MRI signal characteristics and MRI diagnostic accuracy in identifying completely healed menisci repaired with bioabsorbable arrows. A total of 34 patients (38 menisci), with a mean age of 26.0 years, underwent arthroscopic meniscal repair with bioabsorbable arrows and concomitant anterior cruciate ligament (ACL) reconstruction. Of the 34 patients, 27 were male and 7 were female. Of the 38 menisci, 27 were medial and 11 were lateral. Second-look arthroscopy was performed for each patient while taking out the hardware for ACL reconstruction of the tibial side to evaluate the healing status of the repaired menisci. Postoperative MRI was done 2 days before or after second-look arthroscopy. Sagittal T1, T2 and PD images and coronal T2 and PD images were used as the main diagnostic serials. Second-look arthroscopy showed that surfaces of the repaired sites of all 38 menici were almost smooth. In all 38 cases the tail ends of meniscus arrows disappeared and in four patients new overlying injury of compartmental cartilage at the repaired side was detected. MRI results revealed that different serials had different diagnostic accuracy. Sagittal: T1 28.9%, PD 34.2%, T2 60.5%. Coronal: PD 36.8%, T2 65.8%. The double sides Grade 3 signal had a higher proportion in saggital T1 and PD serials, 47.4 and 39.5%, respectively, while lower in sagittal and coronal T2 serials, both 5.3%. MRI diagnostic accuracy was correlated positively with the follow-up time ( P < 0.05). MRI has its limitation in evaluating the status of menisci repaired with bioabsorbable arrows, especially for PD and T1 serials. T2 serials have higher diagnostic accuracy than other serials. MRI diagnostic accuracy can be improved by prolonging follow-up time and might be improved by further classifying Grade 3 signal in terms of signal intensity and the shape of the signal margin. [ABSTRACT FROM AUTHOR]

Supramolecularly constructing multifunctional platform for drug delivery is a challenging task. In this work, we propose a novel supramolecular strategy 'drug chaperone', in which macrocyclic amphiphiles directly coassemble with cationic drugs into a multifunctional platform and its surface is further decorated with targeting ligands through host-guest recognition. The coassembling and hierarchical decoration processes were monitored by optical transmittance measurements, and the size and morphology of amphiphilic coassemblies were identified by dynamic light scattering and high-resolution transmission electron microscopy. In cell experiments to validate the drug chaperone strategy, the anticancer activities of free drugs were pronouncedly improved by coassembling with amphiphilic chaperone and further functionalization with targeting ligand. [ABSTRACT FROM AUTHOR]