As a complex task, robot sorting has become a research hotspot. In order to enable robots to perform simple, efficient, stable and accurate sorting operations for stacked multi-objects in ...unstructured scenes, a robot multi-object sorting system is built in this paper. Firstly, the training model of rotating target detection is constructed, and the placement state of five common objects in unstructured scenes is collected as the training set for training. The trained model is used to obtain the position, rotation angle and category of the target object. Then, the instance segmentation model is constructed, and the same data set is made, and the instance segmentation network model is trained. Then, the optimized Mask R-CNN instance segmentation network is used to segment the object surface pixels, and the upper surface point cloud is extracted to calculate the normal vector. Then, the angle obtained by the normal vector of the upper surface and the rotation target detection network is fused with the normal vector to obtain the attitude of the object. At the same time, the grasping order is calculated according to the average depth of the surface. Finally, after the obtained object posture, category and grasping sequence are fused, the performance of the rotating target detection network, the instance segmentation network and the robot sorting system are tested on the established experimental platform. Based on this system, this paper carried out an experiment on the success rate of object capture in a single network and an integrated network. The experimental results show that the multi-object sorting system based on deep learning proposed in this paper can sort stacked objects efficiently, accurately and stably in unstructured scenes.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Pore-forming proteins play critical roles in pathogenic attack and immunological defence. The membrane attack complex/perforin (MACPF) group of homologues represents, with cholesterol-dependent ...cytolysins, the largest family of such proteins. In this review, we begin by describing briefly the structure of MACPF proteins, outlining their common mechanism of pore formation. We subsequently discuss some examples of MACPF proteins likely implicated in pore formation or other membrane-remodelling processes. Finally, we focus on astrotactin and bone morphogenetic protein and retinoic acid-induced neural-specific proteins, highly conserved MACPF family members involved in developmental processes, which have not been well studied to date or observed to form a pore—and which data suggest may act by alternative mechanisms.
This article is part of the themed issue ‘Membrane pores: from structure and assembly, to medicine and technology’.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
In order to address the causes of compositional variations of crust-derived granitic rocks in continental margin arc, we focused on the petrogenesis of Eocene granitic host rocks with enclosed MMEs, ...associated metagabbro, fine-grained quartz-diorite in Xima-Tongbiguan area, the Tengchong Block, which is a continental margin arc related to the subduction of Neo-Tethys. Both the Eocene granitic and mafic rocks are characterized by gradual increment in enriched compositions, such as K, Rb, Th, LREE, initial 87Sr/86Sr, εNd(t), and εHf(t), but decreasing Pb isotopic ratios from the west to the east of the Tengchong Block.
Zircon UPb age data of granitic host rocks, MMEs, metagabbro and fine-grained quartz-diorite reveal a similar age range of 55–50 Ma. The lithologies, zircon Hf compositions, geochemical and isotopic signatures of host granitic rocks show that the origin of these host rocks are mainly controlled by magma mixing between felsic and mafic magma. The products of the mafic magma are dominated by metagabbro, fine-grained quartz-diorite and MMEs enclosed in granitic rocks, which are all resulted from the reaction and mixture between different mafic magmatic products and felsic magma. The metagabbros could be the products of felsic magma mixing with early crystallized mafic magma, and the fine-grained quartz-diorites could be the products of felsic magma mixing with crystal-rich mafic magma, and the MMEs could be the products of felsic magma mixing with crystal-poor mafic magma or melt. The metagabbro has positive εHf(t) values of 1.8 to 10.9, which could provide the relative primitive LuHf isotopic compositions of mafic magma, indicating that the mafic magma is derived from a depleted mantle. The host granitic rocks have negative εNd(t) values of −5.2 to −6.5, indicating that the felsic magma is derived from partial melting of an ancient mafic lower crust. Furthermore, there are excess reactions after magma mixing between the mafic and felsic magma, such as multi-stage reactions between solidified MMEs and felsic magma, and the disaggregation of MMEs, finally resulting in the basification of felsic magma. Magma mixing is therefore the main mechanism of the formation of granitic rocks in the Tengchong Block. The compositional variation of intermediate to acid igneous rock in a continental margin arc is likely dominated by the characteristics of mafic magma because the intermediate to acid igneous rock is derived from mixing of crust-derived granitic and different mantle sources-derived mafic magma.
•Eocene granitic and mafic rocks in Tengchong block are coeval at 55-50 Ma•Granitic and mafic rocks have similar compositional change and genetic correlation•Compositional change of granitic rock in continental arc is caused by magma mixing
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Perforin-2 (PFN2, MPEG1) is a pore-forming protein that acts as a first line of defense in the mammalian immune system, rapidly killing engulfed microbes within the phagolysosome in macrophages. PFN2 ...self-assembles into hexadecameric pre-pore rings that transition upon acidification into pores damaging target cell membranes. Here, using high-speed atomic force microscopy (HS-AFM) imaging and line-scanning and molecular dynamics simulation, we elucidate PFN2 pre-pore to pore transition pathways and dynamics. Upon acidification, the pre-pore rings (pre-pore-I) display frequent, 1.8 s
, ring-opening dynamics that eventually, 0.2 s
, initiate transition into an intermediate, short-lived, ~75 ms, pre-pore-II state, inducing a clockwise pre-pore-I to pre-pore-II propagation. Concomitantly, the first pre-pore-II subunit, undergoes a major conformational change to the pore state that propagates also clockwise at a rate ~15 s
. Thus, the pre-pore to pore transition is a clockwise hand-over-hand mechanism that is accomplished within ~1.3 s. Our findings suggest a clockwise mechanism of membrane insertion that with variations may be general for the MACPF/CDC superfamily.
A novel trajectory tracking strategy is developed for a double actuated swing in a hydraulic construction robot. Specifically, a nonlinear hydraulic dynamics model of a double actuated swing is ...established, and a parameter adaptive sliding mode control strategy is designed to enhance the trajectory tracking performance. When an object is grabbed and unloaded, the moment of inertia of a swing considerably changes, and the performance of the estimation algorithm is generally inadequate. Thus, it is necessary to establish an algorithm to identify the initial value of the moment of inertia of the object. To this end, this paper proposes a novel initial value identification algorithm based on a two-DOF robot gravity force identification method combined with stereo vision information. The performance of the identification algorithm is enhanced. Simulations and experiments are performed to verify the effect of the novel control scheme.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Novel hybrid nanocomposites constructed via anchoring the Fe3O4@polypyrrole nanospheres with hierarchical porous structure on graphene nanosheets (graphene/Fe3O4@polypyrrole, GFP) have been prepared, ...and characterized by using TEM, XRD, XPS, FT-IR and TGA. The large saturation magnetization of 12.4emug−1 allows fast and economic separation of the GFP from solution. Due to the synergic effect between graphene and Fe3O4@polypyrrole, the GFP exhibits excellent adsorption capability of 348.4mgg−1 for Cr(VI) removal, which is much higher than the previously reported values of other magnetic nanomaterials. Furthermore, the GFP is stable and recyclable, retaining about 72.2% of the removal efficiency after six adsorption–desorption cycles. The adsorption isotherms and kinetics could be well simulated by the Langmuir and pseudo-second-order models respectively. The GFP nanocomposites could be a good candidate for efficient Cr(VI) removal from the wastewater.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Tectonothermal evolution has an important control on maturity and hydrocarbon‐generation of source rocks. On the basis of analysis of the present‐day geothermal gradient, rock thermophysical ...parameters and heat flow, the thickness contour and vitrinite reflectance can be identified, and the distribution of thermal anomaly was discussed. The paleogeotemperature and paleogeothermal gradients are calculated after the recovery of the erosional thickness. With the theory of the recovering of the superposed and modified sedimentary basin, the evolutionary history since the end of Triassic, the end of Jurassic, the Late Early Cretaceous is presented for two sets of source rocks recovered in various perspectives of plans, cross‐sections, important wells, and typical areas. The impact of tectonothermal evolution on the maturity and hydrocarbon‐generation history of the source rocks is discussed. The paleogeothermal gradient (4.0 °C/100 m on average) is higher than the present one (2.9 °C/100 m on average). With the slightly continuous increase since the Late Paleozoic, the paleogeotemperature of the Ordos Basin reached its maximum in Late Early Cretaceous and decreased continuously from then on. The paleogeotemperature and maturity of the source rocks continuously increased before Late Early Cretaceous. The tectonothermal event during Late Jurassic to Early Cretaceous controlled the source rocks with the high temperature and maturity in the Wuqi‐Qingyang‐Fuxian. The temperature decreased, and the maturity hardly changed after the Late Cretaceous. The source rocks of the Shanxi Formation reached maturity, high maturity and over‐maturity at the Late Triassic, the Late Jurassic, and the Early Cretaceous, respectively. The source rocks of the Yanchang Formation reached low maturity and maturity sequentially all in the Early Cretaceous.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Chitin is the second largest biomass on Earth; however, chitinous waste is not well recycled by humans. Specifically, physicochemical methods cause pollution and newly developed techniques are ...expensive. In this case, biorefineries are the most promising method and solid-state fermentation has recently been developed for protein recovery from shrimp shells. Usable chitin-degrading bacteria (CDB) are unavailable and the lack of research on their mechanisms greatly hinders the recycling of chitin. Herein, the newly isolated Chitinibacter sp. SCUT-21 exhibited more robust chitin degradation ability than the presumable major aquatic and terrestrial chitin decomposers Vibrio and Streptomyces . In this study, the genome and transcriptome data showed that 15 of the 20 extracellular chitinolytic enzymes were significantly upregulated by chitin, and 5 recombinant enzymes were identified with their catalytic characteristics. Five transporters, including 2 ChiP, 2 ABC systems, and one PTS system, were significantly upregulated for chitooligosaccharide (COS), (GlcNAc) 2 , and GlcNAc uptake. With chitin as the sole carbon and nitrogen source, GlcNAc shunted from the EMP and TCA cycle into the bifidum pathway and glyoxylate cycle without CO 2 carbon leakage, yielded more ATP, and synthesized poly-β-hydroxybutyrate particles for carbon and energy storage, indicating its adaption for carbon starvation. Proteases and nitrate utilization pathways were significantly upregulated due to nitrogen starvation. The addition of protein could improve the reducing sugar residue in the chitin medium. Expression of the nitrate utilization-associated gene was only induced by (GlcNAc) 2 . Furthermore, we discuss how the mechanisms of SCUT-21 can be used to develop greener chitin biorefinery methods. We hope that this will prompt more research on the mechanisms of CDB and based on their inherent characteristics, more efficient genetically engineered CDB will be constructed for the recovery of chitin. Combining CDB with proteolytic bacteria, full fermentation methods will enable the future recovery of chitinous waste.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The indirect anodic oxidation of chalcone epoxides in the presence of electron-rich heteroarenes mediated by a triarylimidazole (Med) was investigated by cyclic voltammetry (CV) and controlled ...potential electrolysis. The CV results indicate that a homogeneous electron transfer between Med•+ and chalcone epoxides is facilitated by an electron-rich heteroarene that serves as an arylation reagent. The preparative scale electrolysis generated epoxide-ring-opened/Friedel–Crafts arylation products in moderate to good yields. The fact that only a catalytic amount of charge was required suggests that Med•+ initiates a chain reaction. In addition, overoxidation of the products is avoided even though their oxidation potential is less than that of the starting chalcone epoxides.
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IJS, KILJ, NUK, PNG, UL, UM
Diabetes has been indicated to be a risk factor for suicide. We aim to estimate the prevalence of suicide in patients with diabetes.
A meta-analysis using PRISMA methodology was adopted to examine ...the incidence of suicide in diabetic patients.
From inception to October 2022, three online databases (PubMed, China National Knowledge Infrastructure and Web of Science) were used to search studies.
We used random-effects model to analysis. And our primary outcome was the incidence of suicide death per 100 person-years, and other outcomes were prevalence of suicidal ideation and suicide attempt. To explore the sources of heterogeneity in our study, we performed subgroup and meta-regression analyses.
The suicide death rate in diabetic patients was 0.027 per 100 person-years, with a higher rate for Type 1 Diabetes Mellitus compared to Type 2 Diabetes Mellitus. The prevalence of suicidal ideation in diabetes patients was 0.175, with a higher prevalence in Type 1 Diabetes Mellitus compared to Type 2 Diabetes Mellitus. The prevalence of suicide attempts in diabetes patients was 0.033, indicating a higher rate for Type 2 Diabetes Mellitus compared to Type 1 Diabetes Mellitus.
The results indicate a high rate of suicide among people with diabetes, and this study identifies populations and regions at high risk for suicide. Our review emphasizes interventions in mental health and the improvement of suicide prevention programmes.
The study investigated suicide death, suicidal ideation and suicide attempt in diabetic individuals. Suicide rates are elevated among diabetic patients, and various patient groups face distinct suicide risks. It is important to prioritize the mental well-being of diabetic individuals and enhance interventions, including personalized approaches, to inform public health efforts aimed at preventing and addressing suicide among diabetic patients.
No patient or public involvement.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK, VSZLJ
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