Control over Berry Curvature Dipole with Electric Field in WTe_{2}.

Berry curvature dipole plays an important role in various nonlinear quantum phenomena. However, the maximum symmetry allowed for nonzero Berry curvature dipole in the transport plane is a single mirror line, which strongly limits its effects in materials. Here, via probing the nonlinear Hall effect, we demonstrate the generation of Berry curvature dipole by applied dc electric field in WTe_{2}, which is used to break the symmetry constraint. A linear dependence between the dipole moment of Berry curvature and the dc electric field is observed. The polarization direction of the Berry curvature is controlled by the relative orientation of the electric field and crystal axis, which can be further reversed by changing the polarity of the dc field. Our Letter provides a route to generate and control Berry curvature dipole in broad material systems and to facilitate the development of nonlinear quantum devices.

Surgical outcomes of anatomical sublobar resections of left upper lobe and a technique of subsegmentectomy based on bronchovascular patterns.

BACKGROUND: Anatomical sublobar resection was widely performed for small-sized nodule located in the deep field of the lung. In this study, we compared surgical outcomes between anatomical sublobar resection in left upper lobe including segmentectomy and subsegmentectomy. We also applied a technique based on bronchovascular patterns for subsegmentectomy. PATIENTS AND METHODS: A hundred and fifty-one patients underwent anatomical sublobar resection of left upper lobe in our hospital in the period from January 2018 to December 2019 and they were retrospectively reviewed. Patients' characteristics and surgical outcome of the subsegmentectomy group (n = 71) were analyzed and compared to those of patients of the segmentectomy group (n = 80). The bronchovascular patterns of left upper lobe in these patients were also classified, and a technique of subsegmentectomy was introduced by cases description. RESULTS: Compared to segmentectomy, the subsegmentectomy group had longer operative time [141min, interquartile range (IQR): 125-161 vs. 127.5 min, interquartile range (IQR): 114.75-148.25; P = 0.001] and more estimated blood loss [50 mL, IQR: 30-50 vs. 30 mL, IQR: 20-50; P = 0.02]. Branching pattern of bronchus was classified into 3 types in left upper division, and 2 types in lingular division. Branching pattern of pulmonary artery was classified into 7 types in left upper division and 2 types in lingular division. Branching pattern of pulmonary vein was classified into 3 types in left upper division and V3 b was classified into 4 types. CONCLUSION: Subsegmentectomy is a safe procedure with surgical outcome comparable to the one of segmentectomy except operative time and estimated blood loss. Subsegmentectomy based on bronchovascular patterns in left upper lobe is feasible.

Analysis of bronchial and vascular patterns in left upper lobes to explore the genesis of mediastinal lingular artery and its influence on pulmonary anatomical variation.

BACKGROUND: For thoracic surgeons, three-dimensional computed tomography bronchography and angiography (3-DCTBA) is a convenient way to analyze pulmonary variations before segmentectomy. Mediastinal lingular artery (MLA) is one of the representative variations. METHODS: The 3-DCTBA data of left upper lobe (LUL) were collected from patients who underwent pulmonary surgery from January 2018 to December 2019. We reviewed the patterns of bronchi and pulmonary vessels and grouped them according to different classifications. RESULTS: Among all the 404 cases of 3-DCTBA, mediastinal lingular artery (MLA) was found in 107 cases (26.49%). The patterns of B3 and the vein in left upper division (LUD) are distinct between mediastinal (M-type) group and interlobar (IL-type) group. The patterns of bronchi and veins in lingular division, as well as the pattern of pulmonary artery in LUD, have no differences between M-type and IL-type groups. CONCLUSIONS: Mediastinal lingular artery is speculated to originate from the variation of B3, and the MLA independently influences the venous pattern in LUD in turn.

Two new coumarins from Edgeworthia chrysantha.

Two new coumarins, 8-[3-(2,4-benzenediol)-propionic acid methyl ester]-coumarin-7-beta-D-glucoside (1) and 7-hydroxyl-odesmethoxyrutarensin (2), were isolated from the stems and barks of Edgeworthia chrysantha. Their structures were elucidated on the basis of spectroscopic data interpretation.

Prefilming twin-fluid nozzle assisted precipitation method for preparing nanocrystalline HNS and its characterization.

The ultra-fine HNS (2,2',4,4',6,6'-hexanitrostilbene) with desired properties is needed for military and civilian applications because of its reliable threshold energy to short impulse shock waves and its excellent thermal and shock stability. This paper reports on prefilming twin-fluid nozzle assisted precipitation (PTFN-P) to obtain ultra-fine HNS explosive with high specific surface area (SSA), high purity, and narrow particle size distribution. The properties of ultra-fine HNS have been confirmed by SEM, BET, HPLC, XRD, DSC and TGA-SDTA. SEM photograph revealed that the PTFN-P process offers ellipsoid crystalline morphology with particle size of 90-150 nm. The BET and Langmuir SSA of nanocrystalline HNS with purity of 99.44 wt.% were determined to be 19.28 m(2)/g and 29.26 m(2)/g, respectively. The XRD peaks of nanocrystalline HNS seemed to have similar diffraction angles as those of synthesized HNS, and the weakening of peak strength was observed apparently. DSC results of the nanocrystalline HNS showed that the exothermic decomposing at the temperature range of 323-398 degrees C. Furthermore, HNS samples were submitted to impact and small scale gap test and the results indicated that nanocrystalline HNS is less sensitive than synthesized HNS (50 microm) to impact and shock stimuli.

Anti-inflammatory and analgesic activities of Edgeworthia chrysantha and its effective chemical constituents.

The barks and roots of Edgeworthia chrysantha LINDL., which have been used as the folk medicine "Zhu shima" in southern China due to their detumescence and acesodyne effects, were investigated for their anti-inflammatory and analgesic activities using a xylene-induced ear edema assay in mice and Freund's complete adjuvant-induced paw edema as inflammation models, and the acetic acid-induced writhing test as an analgesic model. Fractions effective in terms of anti-inflammatory and analgesic activities were obtained from E. chrysantha. The chloroform-soluble fraction (CHF) showed significant anti-inflammatory (p<0.01-0.001) and analgesic (p<0.01) effects. On further purification by silica gel, three major coumarins, edgeworin (EdN), edgeworosides A and C (EdeA and EdeC), were isolated from the chloroform fraction and both anti-inflammatory and analgesic activities were evaluated. EdN and EdeA had anti-inflammatory (p<0.05-0.01) and analgesic (p<0.001) effects, while EdeC only showed an analgesic effect. The results of this study thus demonstrated that the coumarins EdN, EdeA and EdeC in this plant may be active constituents that contribute to the anti-inflammatory and analgesic effects.