Right upper lobe segmentectomy and subsegmentectomy guided by classification pattern of peripheral segmental veins

BackgroundStudies have analyzed the simplified branching pattern of peripheral segmental veins and developed a standardized approach for intersegmental vein identification in the right upper lobe (RUL). However, the identification approach of intersubsegmental veins has not been reported. This study aimed to supplement the identification approach of intersubsegmental veins and the classification pattern of peripheral segmental veins by using three-dimensional computed tomography bronchography and angiography (3D-CTBA).Materials and methodsA total of 600 patients with ground glass opacity (GGO) who had undergone 3D-CTBA preoperatively at Hebei General Hospital between September 2020 and September 2022 were used for the retrospective study. We reviewed the anatomical variations of RUL veins in these patients using 3D-CTBA images.ResultsAccording to the anatomical position, the peripheral segmental veins structures of RUL were classified into five categories: “Iab type of anterior with central vein” (256/600, 42.7%), “Ib type of anterior with central vein” (166/600, 27.7%), “Central vein type” (38/600, 6.3%), “Anterior vein type” (81/600, 13.5%), “Right top pulmonary vein type” (57/600, 9.5%). The approach for intersegmental vein and intersubsegmental veins identification was divided into five types: anterior approach, posterobronchial approach, central vein approach, V2t approach, and intermediate bronchus posterior surface approach.ConclusionsThe classification pattern of peripheral segmental veins should find wide application. Further, approaches identifying intersegmental veins and intersubsegmental veins may help thoracic surgeons perform safe and accurate RUL segmentectomy

Design and real-time implementation of data-driven adaptive wide-area damping controller for back-to-back VSC-HVDC

This paper proposes a data-driven adaptive wide-area damping controller (D-WADC) for back-to-back VSC-HVDC to suppress the low frequency oscillation in a large-scale interconnected power system. The proposed D-WADC adopts a dual-loop control structure to make full use of the active and reactive power control of VSC-HVDC to improve the damping of the power system. A data-driven algorithm named the goal representation heuristic dynamic programming is employed to design the proposed D-WADC, which means the design procedure only requires the input and output data rather than the mathematic model of the concerned power system. Thus, the D-WADC can adapt to the change of operating condition through online weight modification. Besides, the adaptive delay compensator (ADC) is added to effectively compensate the stochastic delay involved in the wide-area feedback signal. Case studies are conducted based on the simplified model of a practical power system and the 16-machine system with a back-to-back VSC-HVDC. Both the simulation and hardware-in-loop experiment results verify that the proposed D-WADC can effectively suppress the low-frequency oscillation under a wide range of operating conditions, disturbances, and stochastic communication delays

Deep physical structure and geotectonic implications of the eastern margin of the Qinghai–Tibet Plateau

The eastern margin of the Qinghai–Tibet Plateau (QTP) is the focus of studies on eastward lateral extrusion of the latter’s crustal material. This study aims to explore the structural response of the QTP’s eastern crust–mantle to the extrusion, and the basis for the latter’s geological structure. Data on long-period magnetotelluric sounding of cross-tectonic units and Bouguer gravity were used to determine the physical structure of the crust–mantle at the plateau’s eastern margin. The findings are as follows: (i) the apparent density structure indicates extensive presence of a low-density material in the middle–lower crusts of the Songpan and Sichuan–Yunnan blocks at the QTP’s eastern margin. On the other hand, the Yangtze cratonic block (Sichuan Basin) contains a material with a significantly higher density. To the west of the Longmenshan–Panxi tectonic zones, and along the lower crust at 40–50 km depth, is an obvious low-density zone aligned in a northeast–southwest orientation; (ii) the electrical structural model spanning Songpan block–Longmenshan tectonic zone–Yangtze block reveals three distinct electrical structural units along the cross-section bounded by the Longmenshan tectonic zone. The first is the Songpan block, which has high and low resistivity at the shallow layer and middle–lower crusts, respectively. Next is the Yangtze craton, which has low and relatively higher resistivity at the shallow layer and middle–lower crusts, respectively. Third is the Longmenshan transitional tectonic zone, whose shallow layer and deep structure are characterized by an electrical structure with a thrust nappe towards the east, and a high-conductivity material extending to the lithospheric mantle, respectively; (iii) the apparent density and electrical structures indicate that the Panxi tectonic zone has a weakened structure in the lower crust; and (iv) physical properties of the QTP’s deep structure indicate that its eastern margin may contain a middle–lower crustal fluid material with the attributes of high conductivity and low density. Its distribution is closely related to the uplift mechanism and deep seismogenic activities at the QTP’s eastern margin. Estructura profunda e implicaciones geotectónicas del margen oriental del altiplano Qinghai-Tíbet ResumenEl margen oriental del altiplano Qinghai-Tíbet (QTP, del inglés Qinghai-Tibet Plateau) es el área de la extrusión lateral hacia el Este de material cortical. Este trabajo se enfoca en explorar la respuesta estructural de las capas superiores en el altiplano y las bases para su estructuración geológica. Se utilizó información magnetotelúrica y anomalías de Bouguer para determinar la respuesta geofísica de las capas superiores en el margen occidental del altiplano. Dentro de los principales resultados se tiene: (i) la distribución de la densidad aparente indica la presencia de material de baja densidad en las capas medias y bajas de los bloques Songpan y Sichuan-Yunnan en el Este del QTP. Por otro lado, el bloque cratónico Yangtze (en la cuenca Sichuan) contiene material con una mayor densidad. Al oeste de las zonas tectónicas Longmeshan-Panxi, y a lo largo de las capas inferiores, entre 40 y 50 kilómetros de profundidad, hay una zona de baja densidad con orientación noreste-suroeste. (ii) El modelo eléctrico que abarca el bloque Songpan, la zona tectónica Longmeshan y el bloque Yangtze, revela tres unidades a lo largo de la sección cruzada subordinada a la zona tectónica Longmenshan. La primera unidad está en el bloque Songpan, con alta resistividad en la capa superficial y baja en las capas media e inferiores. Luego aparece el cratón Yangtze, con baja resistividad en la superficie y resistividad media en las capas media e inferiores. La tercera unidad es la zona tectónica transicional de Longmenshan, cuya estructura superficial y profunda está caracterizada por una estructura eléctrica asociada a una falla de cabalgamiento hacia el Este y alta conductividad de material que se extiende hacia el manto litosférico. (iii) La densidad aparente y las estructuras eléctricas indican que la zona tectónica de Panxi está debilitada en las capas inferiores. (iv) las propiedades geofísicas de la estructura profunda del altiplano Qinghai-Tíbet muestran que su margen oriental puede contener un fluido de material en las capas bajas y medias con características de alta conductividad y baja densidad. Su distribución está interrelacionada con el mecanismo de elevación y las actividades sismogénicas profundas en el margen oriental del altiplano

Mapping QTLs for the tissue culture performance of rice mature embryo using indica-japonica recombinant inbred lines

Abstract The tissue culture performance is the determinant factor of genetic transformation in indica rice (Oryza sativa L.). Quantitative trait loci (QTLs) associated with the tissue culture performance of mature embryo were detected by 202 genetic markers and 190 recombinant inbred lines (RILs) derived from the cross between two rice varieties, 93-11 (indica) as female parent and Nipponbare (japonica) as male parent. A composite interval mapping (CIM) was used to identify the QTLs for the tissue culture performance. The tissue culture performance of rice mature embryo were evaluated by six parameters, embryogenic calli induction rate (ECR), callus subculture capability (CSC), plantlet regeneration rate (RR), average number of regenerated shoots per callus (NRS), green plantlet regeneration rate (GRR) and average number of regenerated green shoots per callus (NRGS). Nipponbare has better tissue culture response than 93-11 because all indicators were higher in Nipponbare except CSC. Four QTLs for ECR, five QTLs for CSC, three QTLs for RR, two QTLs for NRS, four QTLs for GRR and three QTLs for NRGS were detected. These putative QTLs associated with tissue culture performance were distributed on eight rice chromosomes. These results demonstrated the possibilities of improving the tissue culture performance of indica rice by marker assisted selection (MAS) with those desirable alleles of japonica rice. Keywords: mature embryo; quantitative trait loci (QTLs); rice; recombinant inbred lines (RILs); tissue culture performance. Abbreviations: CAPS-cleaved amplified polymorphic sequence; CIM-composite interval mapping; CSC-callus subculture capability; DH-doubled haploid; ECR-embryogenic calli induction rate; GRR-green plantlet regeneration rate; LOD-logarithm of odds; MAS-marker assisted selection; NRGS-average number of regenerated green shoots per callus; NRS-average number of regenerated shoots per callus; QTLs-quantitative trait loci; RILs-recombinant inbred lines; RR-plantlet regeneration rate; SSRsimple sequence repeats; STS-sequence-tagged site

Creatinine monitoring patterns in the setting of direct oral anticoagulant therapy for non-valvular atrial fibrillation

Guidelines and experts note that patients with atrial fibrillation require regular renal function monitoring to ensure safe use of direct oral anticoagulants (DOACs). Insufficient monitoring could lead to inappropriate dosing and adverse events. Our objective was to describe the frequency of insufficient creatinine monitoring among patients on DOACs, and to describe clinical factors associated with insufficient monitoring. We hypothesized that renal impairment would be associated with insufficient monitoring. A retrospective cohort study was performed with data from the Michigan Anticoagulant Quality Improvement Initiative. Patients were included if they initiated DOAC therapy for stroke prevention related to atrial fibrillation, remained on therapy for ≥ 1 year, and had baseline creatinine and weight measurements. Creatinine clearance (CrCl) was calculated via Cockcroft-Gault equation. Our outcome was the presence of insufficient creatinine monitoring, defined as: \u3c 1 creatinine level/year for patients with CrCl \u3e 50, or \u3c 2 creatinine levels/year for patients with CrCl ≤ 50. Multivariable analysis was done via logistic regression. Study population included 511 patients. In overall, 14.0% of patients received insufficient monitoring. Among patients with CrCl \u3e 50, 11.5% had \u3c 1 creatinine level/year. Among patients with CrCl ≤ 50, 27.1% received \u3c 2 creatinine levels/year. Baseline renal dysfunction was associated with a higher likelihood of insufficient creatinine monitoring (adjusted odds ratio 3.64, 95% confidence interval 1.81-7.29). This shows a significant gap in the monitoring of patients on DOACs-patients with renal impairment are already at higher risk for adverse events. Future studies are needed to describe the barriers in monitoring these patients and to identify how to optimally address them

Negative thermal expansion properties in tetragonal NbPO5 from the first principles studies

By using the first-principles calculations based on density functional theory combined with quasi-harmonic approximation, we have studied the geometric structural, thermal properties, and the negative thermal expansion (NTE) properties of tetrahedral NbPO5. The variations of cell parameter and cell volume of tetrahedral NbPO5 with temperature show that it displays NTE behavior in the range of 473-800 K along a-axis and the corresponding average coefficient of thermal expansion (CTE) is approximately -0.766 ×10−6 K−1, while the c cell parameter and the cell volume display positive thermal expansion behaviors. These results are in consistent well with the experiment observations. Further vibrational modes analysis, together with Grüneisen parameters calculations, revealed that the transverse vibration of O corner atoms accompanying the rocking motions of corner-shared NbO6 octahedron and PO4 tetrahedron dominate the negative thermal properties of tetrahedral NbPO5. Our findings will provide an understanding for the underlying mechanisms of the NTE in oxides materials

Dual-loop SFC scheme for BTB-VSC-HVDC interconnecting asynchronous AC grids

This study proposes a dual-loop supplementary frequency control (SFC) scheme for back-to-back voltage source converter high-voltage DC (BTB-VSC-HVDC) interconnecting asynchronous AC grids, to provide frequency support for each other after a large disturbance. The proposed dual-loop SFC consists of the frequency-active power (f–P) loop and the frequency-reactive power (f–Q) loop. The former deployed on the P-loop of VSC-HVDC can provide frequency support for the disturbed grid during the primary frequency regulation and improve the steady-state characteristics of the frequency response, while the latter attached to the Q-loop of VSC-HVDC supports virtual inertia to ameliorate the transient characteristics of the frequency response. Simulation studies are conducted based on the equivalently simplified model of Southwest Power Grid and Hubei Power Grid interconnected by Chongqing-Hubei BTB-VSC-HVDC. Simulation results show that the proposed SFC scheme can effectively improve the transient and steady-state characteristics of the system frequency response under a wide range of operating condition