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The Western Qinling Orogen (WQO) is characterized by voluminous distribution of Indosinian granitoids, the formation of which provides an important window to unravel the geochemical and geodynamic evolution and associated metallogeny. Here we investigate a group of intrusions termed “Five Golden Flowers” based on petrological, geochemical, zircon U–Pb geochronological and Lu–Hf isotopic studies on the granitoids and their mafic microgranular enclaves (MMEs). Our results show that these intrusions are genetically divided into two types, namely, magma-mixing and highly fractionated. The Jiaochangba, Lujing, Zhongchuan, and Luchuba granitoids are biotite monzogranites (220 ​± ​0.8 ​Ma to 217 ​± ​2.6 ​Ma) with abundant coeval MMEs (220 ​± ​1.1 ​Ma to 217 ​± ​2.7 ​Ma). The rocks contain moderate to high SiO2, high MgO, Rb, Sr, Ba, and Th contents, but low TiO2, P2O5, and Sc values, A/CNK of

Background Total knee arthroplasty (TKA) is an effective and also mature surgical interventions that improves life quality and provides pain relief. Accurate bone cuts are important to prevent TKA malalignment and it requires cautious preoperative plan and precise bone resection. Recently, robotic-assisted TKA techniques have been used to improve the accuracy of bone resection and implantation. However, the system described above suits for only one prosthesis type. Methods Five types (MicroPort_CS, Smith& Nephew_GII, Johnson&Johnson_PFC_PS, kingnow _VLQX_PS and Akmedical_A3GT_PS) implants were included in our study and three Sawbones models were used for each implant. Procedures were performed by experienced joint replacement surgeons using HURWA robotic-assisted TKA system. Results our study indicated that the bone resection error of HURWA robotic-assisted system was below 0.5 mm (with SDs below 0.3 mm), and all of the bone resection angles were below 0.5° (with SDs below 0.3°). The bone resection angles and levels deviation of different brand prosthesis types were below 0.5 mm (with SDs below 0.3 mm) and below 0.5° (with SDs below 0.3°) respectively. Conclusion It suggested that our system may be suitable for different prosthesis types.

Background Robotic-assisted total knee arthroplasty (TKA) was performed to promote the accuracy of bone resection and mechanical alignment. Among these TKA system procedures, 3D reconstruction of CT data of lower limbs consumes significant manpower. Artificial intelligence (AI) algorithms applying deep learning has been proved efficient in automated identification and visual processing. Methods CT data of a total of 200 lower limbs scanning were used for AI-based 3D model construction and CT data of 20 lower limbs scanning were utilised for verification. Results We showed that the performance of an AI-guided 3D reconstruction of CT data of lower limbs for robotic-assisted TKA was similar to that of the operator-based approach. The time of 3D lower limb model construction using AI was 4.7 min. AI-based 3D models can be used for surgical planning. Conclusion AI was used for the first time to guide the 3D reconstruction of CT data of lower limbs for facilitating robotic-assisted TKA. Incorporation of AI in 3D model reconstruction before TKA might reduce the workload of radiologists.

Background We investigated the accuracy and safety of a new HURWA robotic-assisted total knee arthroplasty (TKA) system in a sheep model. Methods Ten male Small-tailed Han sheep were used in this study. Sheep were imaged by computed tomography scan before and after bone resection and the cutting errors between actual bone preparation and preoperative planning of the femur and tibia in 3 dimensions were measured . Results The overall accuracies after surgery compared with that from preoperative surgical planning of the left and right femurs were 1.93±1.02° and 1.93±1.23°, respectively. Additionally, similarly high overall accuracies for the left and right tibia of 1.26±1.04 and 1.68±0.92°, respectively, were obtained. The gap distances of the distal cut, anterior chamfer, anterior cut, posterior chamfer, and posterior cut on the medial side were 0.47±0.35 mm, 0.41±0.37 mm, 0.12±0.26 mm, 0.41±0.44 mm, and 0.12±0.23 mm, respectively. No intraoperative complications, such as intraoperative fracture, massive bleeding or death, occurred CONCLUSION: This new HURWA robotic-assisted TKA system is an accurate and safe tool for TKA surgery based on the sheep model. This article is protected by copyright. All rights reserved.

Recently, in the field of surgical visualization, augmented reality technology has shown incomparable advantages in oral and maxillofacial surgery. However, the current augmented reality methods need to develop personalized occlusal splints and perform secondary Computed Tomography (CT) scanning. These unnecessary preparations lead to high cost and extend the time of preoperative preparation. In this paper, we propose an augmented reality surgery guidance system based on 3D scanning. The system innovatively designs a universal occlusal splint for all patients and reconstructs the virtual model of patients with occlusal splints through 3D scanning. During the surgery, the pose relationship between the virtual model and the markers is computed through the marker on the occlusal splint. The proposed method can replace the wearing of occlusal splints for the secondary CT scanning during surgery. Experimental results show that the average target registration error of the proposed method is \(\text{1.38}\pm \text{0.43 mm}\), which is comparable to the accuracy of the secondary CT scanning method. This result suggests the great application potential and value of the proposed method in oral and maxillofacial surgery.

Elsholtzia splendens is a copper-tolerance plant colonized in copper mines in southern China. In this study, we sequenced and de novo assembled the complete chloroplast genome of E. splendens. The complete chloroplast genome is 150,761 bp (37.8% of GC) in length and contains 87 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. Phylogenetic analysis revealed that among the 11 Lamiaceae species, Perilla citriodor is the closest relative of E. splendens. The complete chloroplast genome of E. splendens provides a valuable resource for comparative and evolutionary analysis among Lamiaceae species and may be helpful in understanding the molecular mechanism of copper tolerance in E. splendens.

The Wenquan Mo deposit in Gansu Province, China, is one of the large porphyry Mo deposits in the Western Qinling Orogen that associated with the Triassic continental collision between the North China Block and South China Block. In this study, detailed fluid inclusions (FIs) analyses were performed on early stage quartz–biotite–K-feldspar veins, middle stage quartz–polymetallic sulfide veins and late stage sulfide–calcite veins. Four compositional types of FIs are observed, including pure CO2 (PC-type), CO2-H2O (C-type), H2O-NaCl (W-type), and daughter mineral-bearing polyphase (S-type, with no halite daughter mineral). The early stage quartz contains all the four types, which are mainly homogenized between 285 °C and 495 °C, with salinities ranging from 4.2 to 17.6 wt% NaCl eqv. However, in the middle stage, PC-type FIs are not observed, and S-, W- and C-types FIs yield homogeneous temperatures (Th) of 200–397 °C and salinities of 2.4–13.1 wt% NaCl eqv. Late stage quartz contains only W-type FIs with Th of 102–246 °C and salinities of 1.2–10.1 wt% NaCl eqv. Results indicate that the fluid-system evolved from an initial CO2-rich magmatic-hydrothermal fluid to a late CO2-poor meteoric fluid. In the early and middle stages, it is possible that heterogeneous FIs associations may have been trapped from a fluid immiscibility system. The dramatically decreasing percentage of PC- and C-types FIs in the ore stage indicates that CO2 escaped, which is possibly the result of earlier fluid immiscibility and phase separation. In addition, there are double peaks of Th in this stage that are obviously lower than in the early stage, showing that meteoric water flowed into and mixed with magmatic fluids, thereby cooling the hydrothermal system. These results suggest that metal precipitation resulted from fluid immiscibility, CO2 escape, and inflow of meteoric water occurred in the middle stage. The initial fluids of the Wenquan deposit are characterized by relatively high temperature, high salinity, high fO2, and are CO2-rich and NaCl-poor, indicating that the Wenquan deposit is a collisional-type porphyry Mo deposit. The oxygen fugacity (fO2) constrained by trace element compositions of zircons from the Wenquan Mo-bearing porphyry is uneven with ΔFMQ −10.3–+4.68 (average of −4.32), which could result from the input of mafic magma and its inhomogeneous mixing with felsic magma. Such values are still much higher than those of the adjacent contemporaneous Mo-barren Lujing, Baijiazhuang, Jiaochangba, Luchuba, and Zhongchuan granitic plutons, which confirms the affinity between Mo mineralization and the oxidized melt system and implies that the Wenquan porphyry has relatively high fO2 characteristics for its tectonic location and epoch. Fluid inclusion, initial mineralization depth (∼8.6 km), magma fO2, and the zircon high U/Yb ratio of the Wenquan Mo deposit strongly suggest that Mo mineralization was related to continental collision, rather than oceanic crust subduction. This study therefore proposes that the Wenquan Mo deposit was formed in a rapid crust uplifting setting caused by syn-orogenic crustal thickening followed by post-orogenic delamination of the lithospheric root during the Late Triassic.

The western Qinling orogen (WQO) is one of the most important prospective gold provinces in China. The Maanqiao gold deposit, located on the southern margin of the Shangdan suture, is a representative gold deposit in the WQO. The Maanqiao deposit is hosted by the metasedimentary rocks of the Upper Devonian Tongyusi Formation. The EW-trending brittle-ductile shear zone controls the orebodies; they occur as disseminated, and auriferous quartz–sulfide vein. The ore-related hydrothermal alteration comprises silicification, sulfidation, sericitization, chloritization, and carbonatization. Native gold is visible and mainly associated with pyrite and pyrrhotite. Mineralization can be classified into the following three stages: bedding-parallel barren quartz–pyrite–(pyrrhotite) (early-stage), auriferous quartz–polymetallic (middle-stage), and carbonate–(quartz)–sulfide (late-stage). Detailed fluid inclusion (FI) studies revealed three types of inclusions in quartz and calcite: aqueous (W-type), CO2–H2O (C-type), and pure carbonic (PC-type) FIs. The primary FIs in the early-stage quartz are C- and PC-type, in the middle-stage quartz are mainly W- and C-type, and in the late-stage calcite are only W-type. During gold mineralization, the total FI homogeneous temperatures evolved from 189–375 °C (mostly 260–300 °C) to 132–295 °C (mostly 180–240 °C) to 123–231 °C (mostly 130–150 °C), and the salinities varied among 2.2–9.1 wt.% NaCl equiv. (mostly 5–8 wt.%) to 0.2–9.0 wt.% NaCl equiv. (mostly 3–6 wt.%) to 0.3–3.6 wt.% NaCl equiv. (mostly 2–4 wt.%). The ore-forming fluid was characterized as an H2O–NaCl−CO2−CH4–(N2) system with medium-low temperature and low salinity. The fluid immiscibility and fluid-rock interaction may be responsible for the precipitation of the sulfides and gold at the Maanqiao gold deposit. Three types of pyrite corresponding to the three mineralization stages, as well as pyrrhotite and arsenopyrite in the middle stage, are micro-analyzed for in-situ sulfur isotopic composition by LA-ICP-MS. Py1 yield near-zero δ34S values of −2.5‰ to 3.0‰, which are somewhat lower than that of the granite hosted pyrites (Py-g, 4.8‰ to 6.6‰). The result suggests a mixed sulfur source from magmatic-hydrothermal fluids and the metamorphism of diagenetic pyrite. Pyrite + pyrrhotite + arsenopyrite assemblages in the middle-stage have relatively higher δ34S values (6.6‰ to 12.3‰) and are mainly developed due to the metamorphism of the ore-host and underlying Devonian sedimentary sequences. The low δ34S values of the late-stage fracture-filled Py3 (−21.9‰ to −17.0‰) resulted from an increasing oxygen fugacity, which was caused by the inflow of oxidized meteoric waters. Based on our studies, the Maanqiao gold deposit is considered to be an orogenic type and closely related to the Indosinian Qinling orogeny.

Pb isotopes are considered an ideal tool for identifying material sources and tectonic settings of various petrogeneses and mineralizations. A high precision method for in-situ Pb isotopic analysis by femtosecond laser-ablation multi-collector inductively coupled plasma mass spectrometry (fsLA-MC-ICP-MS) was first established in China by the State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University. This new method has been used to measure Pb isotopic compositions for inclusions, minerals, glasses, metals, etc., because of its negligible element fractionation and well-corrected mass discrimination. However, Pb isotopic studies on typical deposits using fsLA-MC- ICP-MS have until now rarely been reported globally. The Tongyu copper deposit in the Shaanxi Province, China is one of the most important VHMS deposits with industrial value and is also a typical example of mineralization associated with subduction and metallogenesis during the Caledonian orogeny in the western part of the North Qinling Orogen. Previous studies of this deposit have focused mainly on geological features and ore-forming ages, but detailed isotopic geochemical studies on the ore-forming material sources and tectonic settings were lacking.

The Jinlongshan gold deposit, Shaanxi Province, central China, is a large deposit (>150 t Au) in the Southern Qinling Orogen. Gold mineralization is hosted in Upper Devonian to Lower Carboniferous carbonaceous clastic-carbonate sequences. Four stages of pyrite and paragenetic sulfides have been identified based on morphology and paragenesis. Laser-ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) and laser ablation multi-collector inductively coupled plasma mass spectrometry (LA–MC–ICP–MS) analyses were conducted to determine the chemical and S–Pb isotopic composition of the sulfides. Pre-ore stage pyrites (Py1 and Py2) contain relatively high concentrations of Mn, Co, Ni, Cu, Zn, Sb, and Pb exhibiting a wide range of δ34S values, ranging from –29.9‰ to +48.4‰. These two pyrites were formed by bacterial and thermochemical sulfate reduction of Upper Devonian marine sulfate, respectively. Main-ore stage pyrite (Py3) and arsenopyrite (Apy) contain high concentrations of Au, As, Cu, Sb, Hg, and Tl with restricted ranges of δ34S values from 9.6‰ to 15.3‰, which is interpreted as resulting from the underlying low-grade metamorphic Paleozoic sedimentary rocks by the decomposition of pyrite and/or inorganic reduction of sulfate. Late- or post-ore stage pyrite (Py4) is characterized by low concentrations of Au, Ag, Sn, Hg, and Bi and exhibited variable δ34S values, ranging from –4.4‰ to +27.7‰, that may reflect the mixing of metamorphic fluids with meteoric water. Similarly, the Pb isotope composition of ore-stage sulfides resembles those of underlying low-grade metamorphic Paleozoic sedimentary rocks whereas differs from Precambrian metamorphic basement rocks and granitoids around the basin, indicating that the metals of the Jinlongshan gold deposit were sourced from the underlying Paleozoic sedimentary rocks. Detailed fieldwork revealed that the deposit has mainly undergone four deformation events. The ore bodies developed in NE-trending dextral oblique-slip reverse faults of D3 that crosscut WNW-trending shear zones of D2. The timing and corresponding stress regimes of the D3 event suggest that it formed in a local extensional environment of Yanshanian intracontinental orogeny of Qinling orogenic belt. Gold metallogenesis of the Jinlongshan gold deposit occurred during the transition of tectonic setting from compression to extension, which reactivated the shear zones and migrated deep ore-bearing fluids to NE-trending brittle faults. The geological and geochemical features of the Jinlongshan gold deposit are more analogous to the Carlin-type deposits than other orogenic gold deposits worldwide; therefore, we propose it is a typical Carlin-type gold deposit in South Qinling Orogen.

Elsholtzia splendens is a copper-tolerance plant colonized in copper mines in southern China. In this study, we sequenced and de novo assembled the complete chloroplast genome of E. splendens. The ...