Switching Spinless and Spinful Topological Phases with Projective PT Symmetry

A fundamental dichotomous classification for all physical systems is according to whether they are spinless or spinful. This is especially crucial for the study of symmetry-protected topological phases, as the two classes have distinct symmetry algebra. As a prominent example, the spacetime inversion symmetry PT satisfies (PT)^{2}=±1 for spinless/spinful systems, and each class features unique topological phases. Here, we reveal a possibility to switch the two fundamental classes via Z_{2} projective representations. For PT symmetry, this occurs when P inverses the gauge transformation needed to recover the original Z_{2} gauge connections under P. As a result, we can achieve topological phases originally unique for spinful systems in a spinless system, and vice versa. We explicitly demonstrate the claimed mechanism with several concrete models, such as Kramers degenerate bands and Kramers Majorana boundary modes in spinless systems, and real topological phases in spinful systems. Possible experimental realization of these models is discussed. Our work breaks a fundamental limitation on topological phases and opens an unprecedented possibility to realize intriguing topological phases in previously impossible systems.

[Breast ultrasound optimization process analysis based on breast cancer screening for 1 501 753 rural women in China]

Objective: To evaluate the effectiveness and quality of ultrasound-based (BUS) process optimization in breast cancer screening. Methods: The program collected the first to fourth quarterly breast cancer screening statistic data and case report data from 30 provinces, autonomous regions and municipalities in 2015 by the online report system of national key service program of women and children's public health. The call rate, mammography (MG) subsequent screen rate, biopsy rate, detection rate, early diagnosis rate, carcinoma in situ rate, missing detection rate, false positive rate and positive predictive value (PPV) of breast cancer were calculated. Results: A total of 1 501 753 rural women attended the BUS process optimization screening. The nationwide recall rate was 3.01%(45 156/1 501 753), and in the eastern and central area were 3.41%(17 173/503 130) and 3.56%(14 499/407 739), respectively, higher than 2.28% (13 484/590 884) of western area (P<0.05). The nationwide MG subsequent screen rate was 2.78%(41 694/1 501 753), and in the eastern and central area were 3.19%(16 036/503 130) and 3.29% (13 421/407 739), respectively, higher than 2.07%(12 237/590 884) of western area (P<0.05). The nationwide biopsy rate was 0.23%(3 462/1 501 753), and in the central area were 0.26%(1 078/407 739), respectively, higher than 0.21%(1 247/590 884) of western area and 0.23% (1 137/503 130) of eastern area (P<0.05). The nationwide biopsy PPV was 37.00%(1 281/3 462). The biopsy PPV of eastern area was (34.30%, 390/1 137), lower than 39.33% (424/1 078) of central area (P<0.05). A total of 1 281 cases of breast cancer were detected, the detection rate was 0.85‰(1 281/1 501 753), and the detection rates of central area was 1.04‰ (424/407 739), higher than 0.79‰(467/590 884) of western area and 0.78‰(390/503 130) of eastern area (P<0.05). The BUS initiate screening positive rate from detected breast cancer cases was 96.96%(1 242/1 281), the MG subsequent screening positive rate was 2.42%(31/1 281). The nationwide early diagnosis rate was 85.25%(1 092/1 281), and in the eastern and central areas were 87.95%(343/390) and 88.21%(374/424), higher than 80.30%(375/467) of western area (P<0.05). The screening rate of on or above stage Ⅱ breast cancer in eastern area was 55.64%(217/390), lower than 64.62%(374/424) of central area and 62.31%(291/467) of western area. The missing detection rate was 0.62%(8/1 281) and false positive rate was 1.20%(17 528/1 464 149). Conclusions: The BUS process optimization of breast cancer screening scheme is reasonable and applicable to China rural women. The effectiveness and quality of eastern area are superior to those of central and western area.

Acupuncture for Paclitaxel-Induced Peripheral Neuropathy: A Review of Clinical and Basic Studies

Paclitaxel-induced peripheral neuropathy (PIPN) is a common and intractable side effect of the conventional chemotherapeutic agent paclitaxel. Acupuncture has been reported as an effective alternative therapy in treatment of PIPN in both basic studies and clinical trials. However, there is a lack of comprehensive surveys to summarize the action of acupuncture in management of PIPN. In this review, we briefly demonstrate the basic pathology of PIPN, which includes the activation of ion channels, mitochondrial dysfunction, disruption of axonal transport and also neuro-inflammatory involvement. Meanwhile, we review both the clinical and basic studies as an emphasis to give a general overview of the therapeutic effect of acupuncture against PIPN. Finally, we summarize the current known mechanisms underlying the action of acupuncture against PIPN mainly at peripheral and spinal levels, which include various neurotransmitters, multiple receptors, different types of enzymes and molecules. In conclusion, acupuncture could be considered as a potential alternative therapy in treatment of PIPN, and further clinical and experimental studies are called for in the future.

Observation of a Near-Threshold Structure in the K^{+} Recoil-Mass Spectra in e^{+}e^{-}→K^{+}(D_{s}^{-}D^{*0}+D_{s}^{*-}D^{0})

We report a study of the processes of e^{+}e^{-}→K^{+}D_{s}^{-}D^{*0} and K^{+}D_{s}^{*-}D^{0} based on e^{+}e^{-} annihilation samples collected with the BESIII detector operating at BEPCII at five center-of-mass energies ranging from 4.628 to 4.698 GeV with a total integrated luminosity of 3.7  fb^{-1}. An excess of events over the known contributions of the conventional charmed mesons is observed near the D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0} mass thresholds in the K^{+} recoil-mass spectrum for events collected at sqrt[s]=4.681  GeV. The structure matches a mass-dependent-width Breit-Wigner line shape, whose pole mass and width are determined as (3982.5_{-2.6}^{+1.8}±2.1)  MeV/c^{2} and (12.8_{-4.4}^{+5.3}±3.0)  MeV, respectively. The first uncertainties are statistical and the second are systematic. The significance of the resonance hypothesis is estimated to be 5.3  σ over the contributions only from the conventional charmed mesons. This is the first candidate for a charged hidden-charm tetraquark with strangeness, decaying into D_{s}^{-}D^{*0} and D_{s}^{*-}D^{0}. However, the properties of the excess need further exploration with more statistics.

[Characteristics of "deqi" and myoelectricity in different tissue structures of acupoint]

OBJECTIVE

To investigate the effect of acupuncture in different tissue structures on deqi and the electromyography of acupoint area.

METHODS

Twenty healthy subjects, respectively accepted 4 kinds of needling stimulation, i.e. stimulating skin at Zusanli (ST36), stimulating ST36 with and without skin anesthesia using compound lidocaine cream, and stimulating at Dubi (ST35) without skin anesthesia. Deqi sensation of the acupuncturist and subjects were measured according to MGH Acupuncture Sensation Scale (MASS) during needling, and the myoelectricity around the acupoints was recorded simultaneously. The occurrence rate and intensity of the different deqi sensations, the relationship between the acupuncturist's and subjects' deqi sensations, and the integrated electromyogram (iEMG) were analyzed.

RESULTS

Sharp pain and tingling were the main sensations during skin needling at ST36. Fullness, dull pain, soreness and acupuncturist's tightness were the main sensations during needling with or without skin anesthesia at ST36. Fullness was the main sensation during needling at ST35, while the intensity was lower than that during needling at ST36. A positive correlation in the intensity was found between subjects' fullness and acupuncturist's tightness during needling with or without skin anesthesia at ST36. The subjects' fullness appeared earlier about 5 seconds than acupuncturist's tightness. The iEMGs during subjects' fullness and acupuncturist's tightness were 2-3 times of that before needling.

CONCLUSION

Deqi sensations such as subjects' fullness, dull pain, soreness and acupuncturist's tightness are mainly related to the activity of the muscles under the acupoints. Subjects' fullness and acupuncturist's tightness always appear together. Acupuncturist's tightness may be mediated by the muscle stretch reflex induced by needling stimulation.

Chloroplast genome of Trapa bispinosa Roxb. (Trapa, Lythraceae)

Trapa bispinosa Roxb. is an annual aquatic herb with great significance of medicinal, edible and economic value. Here, we reported the complete chloroplast genome sequence of Trapa bispinosa and conducted preliminary investigation of its phylogenetic relationship with other related species. As the result showed, the whole chloroplast genome size was 155,556 bp consisting of four adjoining regions, i.e., a large/small single copy (LSC, 88,506 bp/SSC, 18,274 bp) region and two inverted repeat (IRs, 24,388 bp) regions. Among 112 identified unique genes were 78 protein coding genes, 30 transfer RNA (tRNA) genes, and four ribosomal RNA (rRNA) genes. Trapa spp. were precisely clustered as a monophyly, and simultaneously, the closest relation between Trapa bispinosa and Trapa natans were strongly supported in the maximum likelihood analysis.

Index Theorem on Chiral Landau Bands for Topological Fermions

Topological fermions as excitations from multidegenerate Fermi points have been attracting increasing interest in condensed matter physics. They are characterized by topological charges, and magnetic fields are usually applied in experiments for their detection. Here we present an index theorem that reveals the intrinsic connection between the topological charge of a Fermi point and the in-gap modes in the Landau band structure. The proof is based on mapping fermions under magnetic fields to a topological insulator whose topological number is exactly the topological charge of the Fermi point. Our Letter lays a solid foundation for the study of intriguing magnetoresponse effects of topological fermions.

[Initial implantation experience and short-term follow-up results of implanting leadless intracardiac transcatheter pacing system]

Objective: To explore the utility and safety of leadless intracardiac transcatheter pacing system. Methods: The study was a prospective observational study. Patients underwent Micra transcatheter pacing system in Beijing Anzhen hospital from December 2019 to January 2020 were enrolled. The baseline characteristics, platelet count, hemoglobin, anticoagulation and/or antiplatelet therapy, mean procedural time, average fluoroscopy time, number of deployment and electrical parameters (threshold, R-wave amplitude, impedance) were recorded. Ultrasonography of bilateral femoral and iliac veins was performed in all patients. Patients were followed including access site complication, adverse event and device evaluation at implant, hospital discharge, 1 and 3 months post-implant. R-wave≥5 mV, impedance between 400 and 1 500 Ω and threshold increase≤1.5 V than implant is considered a stable parameter. Femoral access site complications included hematoma, hemorrhage, pseudoaneurysm, and arteriovenous fistula. Adverse events included dislodgement, cardiac effusion/perforation and infection. Left ventricular end diastolic diameter and ejection fraction before and at 1 month after implant were reported. Results: Five patients were enrolled and pacemaker implantation was successful in all 5 patients. Patients were all males and the average age was (78.4±8.4) years. 2 patients received aspirin and clopidogrel therapy, 1 patient suffered from anemia and thrombocytopenia occurred in 1 patient. No stenosis, occlusion and vascular malformation of bilateral femoral and iliac veins was observed. The mean implant time was (39.6±1.7) minutes. The average fluoroscopy time was (9.2±1.3) minutes and the number of deployment was (1.40±0.55). Electrical parameters(threshold, R-Wave amplitude and impedance) were as follows: (0.40±0.10) V/0.24 ms, (10.80±3.72) mV and (822.00±162.23) Ω at implant; (0.45±0.07) V/0.24 ms, (13.04±2.41) mV, and (748.0±91.5) Ω at discharge, (0.40±0.06) V/0.24 ms, (14.26±4.11) mV, and (700.0±91.7) Ω at 1 month post-implant and (0.39±0.05) V/0.24 ms, 14.40±3.97 mV, and (682.0±96.0) Ω at 3 months post-implant, respectively. Threshold increase was ≤1.5 V compared to that during implantation, electrical parameters were acceptable and stable. There was no difference in LVEDD [(44.00±5.24) mm vs. (44.00±5.34) mm,P=1.000] and EF [(62.00±3.39)% vs. (62.20±3.56)%, P=0.861] before and 1 month post-implant. No incidence of access site complications, cardiac effusion/perforation, dislodgment or infections occurred during the 3 months. Conclusions: The leadless transcatheter pacemaker implantation performed in our study archived a high implant success rate and favorable safety profile as well as associated with low and stable pacing thresholds. The long-term safety and benefit of leadless pacemaker need to be evaluated in future clinical studies.

Observation of the Doubly Cabibbo-Suppressed Decay D^{+}→K^{+}π^{+}π^{-}π^{0} and Evidence for D^{+}→K^{+}ω

Using 2.93  fb^{-1} of e^{+}e^{-} collision data collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, the first observation of the doubly Cabibbo-suppressed decay D^{+}→K^{+}π^{+}π^{-}π^{0} is reported. After removing decays that contain narrow intermediate resonances, including D^{+}→K^{+}η, D^{+}→K^{+}ω, and D^{+}→K^{+}ϕ, the branching fraction of the decay D^{+}→K^{+}π^{+}π^{-}π^{0} is measured to be (1.13±0.08_{stat}±0.03_{syst})×10^{-3}. The ratio of branching fractions of D^{+}→K^{+}π^{+}π^{-}π^{0} over D^{+}→K^{-}π^{+}π^{+}π^{0} is found to be (1.81±0.15)%, which corresponds to (6.28±0.52)tan^{4}θ_{C}, where θ_{C} is the Cabibbo mixing angle. This ratio is significantly larger than the corresponding ratios for other doubly Cabibbo-suppressed decays. The asymmetry of the branching fractions of charge-conjugated decays D^{±}→K^{±}π^{±}π^{∓}π^{0} is also determined, and no evidence for CP violation is found. In addition, the first evidence for the D^{+}→K^{+}ω decay, with a statistical significance of 3.3σ, is presented and the branching fraction is measured to be B(D^{+}→K^{+}ω)=(5.7_{-2.1}^{+2.5}_{stat}±0.2_{syst})×10^{-5}.

[New thoughts about study on cholinergic anti-inflammatory pathway in mediating delaying effect of electroacupuncture on myocardial remodeling of chronic hypertension]

Chronic hypertension evoked aberrant myocardial remodeling is the main reason for progressive death from heart failure. It is of great clinical significance to find effective prevention and treatment methods to block this pathological process. It has been shown that imbalance of the autonomic nervous system (ANS) induced by chronic hypertension, i.e., hyper-excitation of sympathetic nerve system and suppression of parasympathetic (vagal) nerve system, activates immune cells-mediated inflammatory responses, and exacerbates the pathological remodeling of cardiac tissue. Except the negative inotropic outcomes, excitation of vagal nerves also has an anti-inflammatory effect which is mediated by activating the cholinergic anti-inflammatory pathway (CAIP). Previous studies showed that electroacupuncture (EA) could exert anti-hypertensive and systematic anti-inflammatory effects by increasing vagal activity. In addition, preliminary study from our lab demonstrated that EA was able to alleviate the pathological progress from hypertension to cardiac hypertrophy. However, the potential role of CAIP in restoring hypertension induced aberrant myocardial remodeling is still unknown. Herein, based on the alteration of ANS function in hypertension and EA's impact on vagal activity, we propose novel research ideas that EA could attenuate the pathological process of hypertension induced abnormal myocardial remodeling via activating CAIP.

Boundary Criticality of PT-Invariant Topology and Second-Order Nodal-Line Semimetals

For conventional topological phases, the boundary gapless modes are determined by bulk topological invariants. Based on developing an analytic method to solve higher-order boundary modes, we present PT-invariant 2D topological insulators and 3D topological semimetals that go beyond this bulk-boundary correspondence framework. With unchanged bulk topological invariants, their first-order boundaries undergo transitions separating different phases with second-order boundary zero modes. For the 2D topological insulator, the helical edge modes appear at the transition point for two second-order topological insulator phases with diagonal and off-diagonal corner zero modes, respectively. Accordingly, for the 3D topological semimetal, the criticality corresponds to surface helical Fermi arcs of a Dirac semimetal phase. Interestingly, we find that the 3D system generically belongs to a novel second-order nodal-line semimetal phase, possessing gapped surfaces but a pair of diagonal or off-diagonal hinge Fermi arcs.

Antihypertensive and Antifibrosis Effects of Acupuncture at PC6 Acupoints in Spontaneously Hypertensive Rats and the Underlying Mechanisms

Long-term hypertension can lead to both structural and functional impairments of the myocardium. Reversing left ventricular (LV) myocardial fibrosis has been considered as a key goal for curing chronic hypertension and has been a hot field of research in recent years. The aim of the present work is to investigate the effect of electroacupuncture (EA) at PC6 on hypertension-induced myocardial fibrosis in spontaneously hypertensive rats (SHRs). Thirty SHRs were randomized into model, SHR + EA, and SHR + Sham EA groups with WKY rats as a normal control. EA was applied once a day for 8 consecutive weeks. The cardiac fibrosis as well as the underlying mechanisms were investigated. After 8 weeks of EA treatment at PC6, the enhanced myocardial fibrosis in SHRs was characterized by an increased ratio of left ventricular mass index (LVMI), collagen volume fraction (CVF), and elevated content of hydroxyproline (Hyp) as well as the upregulated expression of collagen I and collagen III in myocardium tissue of SHRs. All these abnormal alterations in the SHR + EA group were significantly lower compared to the model group. In addition, EA at PC6 significantly improved the pathological changes of myocardial morphology. Meanwhile, the increased levels of angiotensin II (Ang II) and tumor necrosis factor-α (TNFα) and expression of transforming growth factor β1 (TGF-β1), connective tissue growth factor (CTGF), matrix metalloproteinase (MMP)-2, and MMP-9 in the serum or heart tissue of SHRs were also markedly diminished by EA. These results suggest that EA at bilateral PC6 could ameliorate cardiac fibrosis in SHRs, which might be mediated by the regulation of the Ang II – TGF-β₁ pathway.

[Analysis of treatment response and prognostic factors of T-LBL patients treated with pediatric-like ALL therapy following HSCT]

目的

探讨经急性淋巴细胞白血病（ALL）儿童方案治疗达到完全缓解（CR）和部分缓解（PR）的T淋巴母细胞淋巴瘤（T-LBL）患者应用造血干细胞移植巩固治疗的疗效及预后因素。

方法

收集2013年1月至2017年1月于唐都医院血液病中心接受治疗的T-LBL患者的临床资料，将达到CR或PR的患者纳入研究，进行回顾性分析。

结果

①48例患者接受了ALL儿童方案治疗，经2个疗程的诱导化疗后39例达CR，9例达PR。其中接受自体造血干细胞移植（auto-HSCT）者14例，接受异基因造血干细胞移植（allo-HSCT）者7例，21例患者移植后造血功能均顺利重建。②中位随访时间31（9～16）个月。3年总生存（OS）率为61.0%（95% CI 53.7%～68.3%），3年无进展生存（PFS）率为54.8%（95% CI 47.1%～62.2%）。③移植组和未移植组3年OS率分别为84.7%和42.8%（P＝0.006），两组3年PFS率分别为75.4%和38.9%（P＝0.004）。④auto-HSCT组与allo-HSCT组患者的OS率、PFS率差异均无统计学意义（P值分别为0.320、0.597）。⑤骨髓侵犯、未接受造血干细胞移植是影响患者长期预后的独立危险因素［ HR＝5.804（95% CI 1.140～29.549），P＝0.034；HR＝5.871（95% CI 1.711～20.140），P＝0.005］。

结论

ALL儿童方案化疗序贯造血干细胞移植治疗T-LBL疗效确切，安全性好。auto-HSCT与allo-HSCT患者的OS率及PFS率差异均无统计学意义。骨髓侵犯、未接受造血干细胞移植是影响T-LBL患者长期预后的独立危险因素。

Identification of Peripheral Blood and Menstrual Blood Based on the Expression Level of MicroRNAs and Discriminant Analysis

Objective To construct a discriminant analysis model based on the differential expression of multiple microRNAs （miRNAs） in two kinds of blood samples （peripheral blood and menstrual blood） and three non-blood samples （saliva, semen and vaginal secretion）, to form an identification solution for peripheral blood and menstrual blood. Methods Six kinds of miRNA （miR-451a, miR-144-3p, miR-144-5p, miR-214-3p, miR-203-3p and miR-205-5p） were selected from literature, the samples of five kinds of body fluids commonly seen in forensic practice （peripheral blood, menstrual blood, saliva, semen, vaginal secretion） were collected, then the samples were divided into training set and testing set and detected by SYBR Green real-time qPCR. A discriminant analysis model was set up based on the expression data of training set and the expression data of testing set was used to examine the accuracy of the model. Results A discriminant analysis statistical model that could distinguish blood samples from non-blood samples and distinguish peripheral blood samples from menstrual blood samples at the same time was successfully constructed. The identification accuracy of the model was over 99%. Conclusion This study provides a scientific and accurate identification strategy for forensic fluid identification of peripheral blood and menstrual blood samples and could be used in forensic practice.

Electroacupuncture ameliorates corticotrophin-releasing factor-induced jejunal dysmotility in a rat model of stress

BACKGROUND

Central injection of corticotrophin-releasing factor (CRF) mimics the effect of stress on gastrointestinal (GI) responses, including inhibition of GI motility. This study was designed to explore the effects of electroacupuncture (EA) on disordered jejunal motility in a rat model of stress induced by intracisternal (IC) injection of CRF.

METHODS

A stress model was established by IC injection of CRF in Sprague-Dawley rats. GI motility was evaluated by assessing gastric emptying (GE), gastrointestinal transit (GIT) and jejunal motility in vivo. EA was performed at ST36. The functional roles of CRF receptor subtype 1 and subtype 2 (CRFr1 and CRFr2) were examined by IC administration of the corresponding selective CRF antagonists. Protein expression of CRFr1 and CRFr2 in the hypothalamus and jejunum was detected by Western blotting.

RESULTS

IC injection of CRF significantly inhibited GE, GIT and jejunal motility. EA treatment remarkably improved the disturbed GI motility. Intriguingly, the disordered jejunal motility induced by central CRF was abolished by IC injection of a selective CRFr2 antagonist, indicating the essential role of central CRFr2 in mediating the stress-induced jejunal motor disorder. EA at ST36 decreased central and peripheral expression of CRFr2, which might be one of the potential mechanisms underlying the beneficial effect of EA on jejunal dysmotility in this rat model of stress.

CONCLUSION

This study suggested that EA at ST36 could ameliorate disordered jejunal motility induced by stress, and that this might be associated with the down-regulation of CRFr2.

Measurements of Absolute Branching Fractions of Fourteen Exclusive Hadronic D Decays to η

Using 2.93  fb^{-1} of e^{+}e^{-} collision data taken at a center-of-mass energy of 3.773 GeV with the BESIII detector, we report the first measurements of the absolute branching fractions of 14 hadronic D^{0(+)} decays to exclusive final states with an η, e.g., D^{0}→K^{-}π^{+}η, K_{S}^{0}π^{0}η, K^{+}K^{-}η, K_{S}^{0}K_{S}^{0}η, K^{-}π^{+}π^{0}η, K_{S}^{0}π^{+}π^{-}η, K_{S}^{0}π^{0}π^{0}η, and π^{+}π^{-}π^{0}η; D^{+}→K_{S}^{0}π^{+}η, K_{S}^{0}K^{+}η, K^{-}π^{+}π^{+}η, K_{S}^{0}π^{+}π^{0}η, π^{+}π^{+}π^{-}η, and π^{+}π^{0}π^{0}η. Among these decays, the D^{0}→K^{-}π^{+}η and D^{+}→K_{S}^{0}π^{+}η decays have the largest branching fractions, which are B(D^{0}→K^{-}π^{+}η)=(1.853±0.025_{stat}±0.031_{syst})% and B(D^{+}→K_{S}^{0}π^{+}η)=(1.309±0.037_{stat}±0.031_{syst})%, respectively. The charge-parity asymmetries for the six decays with highest event yields are determined, and no statistically significant charge-parity violation is found.

First Observation of D^{+}→ημ^{+}ν_{μ} and Measurement of Its Decay Dynamics

By analyzing a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, we measure for the first time the absolute branching fraction of the D^{+}→ημ^{+}ν_{μ} decay to be B_{D^{+}→ημ^{+}ν_{μ}}=(10.4±1.0_{stat}±0.5_{syst})×10^{-4}. Using the world averaged value of B_{D^{+}→ηe^{+}ν_{e}}, the ratio of the two branching fractions is determined to be B_{D^{+}→ημ^{+}ν_{μ}}/B_{D^{+}→ηe^{+}ν_{e}}=0.91±0.13_{(stat+syst)}, which agrees with the theoretical expectation of lepton flavor universality within uncertainty. By studying the differential decay rates in five four-momentum transfer intervals, we obtain the product of the hadronic form factor f_{+}^{η}(0) and the c→d Cabibbo-Kobayashi-Maskawa matrix element |V_{cd}| to be f_{+}^{η}(0)|V_{cd}|=0.087±0.008_{stat}±0.002_{syst}. Taking the input of |V_{cd}| from the global fit in the standard model, we determine f_{+}^{η}(0)=0.39±0.04_{stat}±0.01_{syst}. On the other hand, using the value of f_{+}^{η}(0) calculated in theory, we find |V_{cd}|=0.242±0.022_{stat}±0.006_{syst}±0.033_{theory}.

First Observation of D^{+}→ημ^{+}ν_{μ} and Measurement of Its Decay Dynamics

By analyzing a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy of 3.773 GeV with the BESIII detector, we measure for the first time the absolute branching fraction of the D^{+}→ημ^{+}ν_{μ} decay to be B_{D^{+}→ημ^{+}ν_{μ}}=(10.4±1.0_{stat}±0.5_{syst})×10^{-4}. Using the world averaged value of B_{D^{+}→ηe^{+}ν_{e}}, the ratio of the two branching fractions is determined to be B_{D^{+}→ημ^{+}ν_{μ}}/B_{D^{+}→ηe^{+}ν_{e}}=0.91±0.13_{(stat+syst)}, which agrees with the theoretical expectation of lepton flavor universality within uncertainty. By studying the differential decay rates in five four-momentum transfer intervals, we obtain the product of the hadronic form factor f_{+}^{η}(0) and the c→d Cabibbo-Kobayashi-Maskawa matrix element |V_{cd}| to be f_{+}^{η}(0)|V_{cd}|=0.087±0.008_{stat}±0.002_{syst}. Taking the input of |V_{cd}| from the global fit in the standard model, we determine f_{+}^{η}(0)=0.39±0.04_{stat}±0.01_{syst}. On the other hand, using the value of f_{+}^{η}(0) calculated in theory, we find |V_{cd}|=0.242±0.022_{stat}±0.006_{syst}±0.033_{theory}.

[Study on the matching feature of current parameters for inducing contraction of orbicularis oris muscle by artificial facial nerve in rabbit with peripheral facial paralysis]

Objective: To explore the optimal matching of the current parameters about artificial facial nerve (AFN) for inducing contraction of the orbicularis oris muscle (OOM) in rabbit with peripheral facial paralysis. Methods: According to the combinations of different stimulus parameters, at different time points, we used AFN to induce contraction of the affected side OOM of the paralyzed rabbit in waking state. We recorded the current amplitudes of the threshold stimulation and peak stimulation under each combination, then compared the total charge of the stimulus consumption under different combinations. Results: Compared the total stimulus charge consumption of the AFN threshold stimulation and that in the peak stimulation respectively under different stimulus frequency and pulse width matching combinations, we found that the frequency, the pulse width and the interaction of the frequency and pulse width among different groups could affect the total charge, the differences were statistically significant (P<0.05). Conclusions: When AFN stimulus frequency is 60 Hz and the stimulus pulse width is 100 μs, the output current intensity is relatively lowest and the total consumed charge is the lowest under the premise of effectively inducing the paralytic side OOM contraction. Thus we recommend this stimulus parametric combination as the optimal combination for meeting the low power consumption of AFN.

4D spinless topological insulator in a periodic electric circuit

According to the mathematical classification of topological band structures, there exist a number of fascinating topological states in dimensions larger than three with exotic boundary phenomena and interesting topological responses. While these topological states are not accessible in condensed matter systems, recent works have shown that synthetic systems, such as photonic crystals or electric circuits, can realize higher-dimensional band structures. Here, we argue that, because of its symmetry properties, the 4D spinless topological insulator is particularly well suited for implementation in these synthetic systems. We explicitly construct a 2D electric circuit lattice, whose resonance frequency spectrum simulates the 4D spinless topological insulator. We perform detailed numerical calculations of the circuit lattice and show that the resonance frequency spectrum exhibits pairs of 3D Weyl boundary states, a hallmark of the nontrivial topology. These pairs of 3D Weyl states with the same chirality are protected by classical time-reversal symmetry that squares to +1, which is inherent in the proposed circuit lattice. We also discuss how the simulated 4D topological band structure can be observed in experiments.

[The prevalence and relationship between laryngopharyngeal reflux disease, anxiety and depression in otolaryngology outpatients]

Objective: To obtain the prevalence laryngopharyngeal reflux disease (LPRD), anxiety and depression in otorhinolaryngology outpatients and to explore the role of mental and psychological factors (anxiety and depression) in their pathogenesis. Methods: A questionnaire survey of reflux symptom index(RSI) scale and hospital anxiety and depression (HAD) scale were used to report 1 111 cases of outpatients in Department of Otorhinolaryngology Head and Neck Surgery, Peking University People's Hospital, from July 2017 to June 2018 (486 males, 625 females, age of 18-96 years old, median age of 38[30,53] years old) and to obtain the prevalence of LPRD, anxiety and depression. RSI-positive patients were selected in the case group, and RSI-negative patients were selected in the control group. The differences in HAD scores between the two groups were compared, and the risk factors of laryngopharyngeal reflux were analyzed. Statistical analysis was performed using SPSS 20.0 software. Results: There were 151 cases in the case group and 960 cases in the control group. The prevalence of LPRD was 13.59% (151/1 111).There was no significant difference in the prevalence of LPRD between different genders (P>0.05). The prevalence rate was the highest in the 18-40 age group, and the difference in the prevalence of all age groups (18~ 40 years old; 41-65 years old; >65 years old) was statistically significant (P<0.05). The prevalence of LPRD among smokers and non-drinkers was higher than that of non-smokers and non-drinkers and the prevalence of the two groups was statistically significant (P<0.05). The most common symptoms of the RSI scale were pharyngeal foreign body sensation (92.72%,140/151), persistent clearing throat (88.74%,124/151), excessive sputum or nasal reflux (82.12%, 124/151). There were significant statistical differences between the two groups (P<0.05). Ninty-one patients with anxiety, the prevalence was 8.19%(91/1 111); 76 patients with depression, the prevalence was 6.84%(76/1 111).Among the LPRD patients, the hospital anxiety scale scored 29.14% (44/151), and the hospital depression scale scored 17.22% (26/151). The scores of anxiety symptoms and depressive symptoms in the LPRD group were higher than those in the non-LPRD group. The above scores were statistically significant (P<0.05). Logistic regression analysis showed that smoking, anxiety and symptoms of gastroesophageal reflux disease were independent risk factors for laryngopharyngeal reflux. Conclusions: The prevalences of LPRD, anxiety and depression in the otorhinolaryngology clinic are 13.59%, 8.19% and 6.84%, respectively. Among patients with laryngopharyngeal reflux, the prevalence of anxiety is 29.14%, and the prevalence of depression is 17.22%. Age, smoking, drinking, alcohol consumption, education level, course of disease, symptoms of gastroesophageal reflux disease, pharyngeal foreign body sensation, etc. are related to LPRD. Mental factors (anxiety and depression) may play a role in LPRD. Smoking, anxiety symptoms and symptoms of gastroesophageal reflux disease are closely related to the incidence of LPRD.

Electroacupuncture Treatment Attenuates Paclitaxel-Induced Neuropathic Pain in Rats via Inhibiting Spinal Glia and the TLR4/NF-κB Pathway

Background and Purpose

Neuropathic pain is a major side-effect of paclitaxel (PTX) chemotherapy. Although the precise mechanisms responsible for this pain are unclear, the activation of neuroglia and upregulation of the TLR4/NF-κB pathway are known to be involved. In this study, we determined whether electroacupuncture (EA) could limit mechanical hypersensitivity resulting from the chemotherapeutic drug PTX in rats, and investigated the potential mechanisms involved.

Methods

Rats intraperitoneally received a cumulative dose of 8 mg/kg PTX (2 mg/kg per day) or vehicle control on alternate days (day 0, 2, 4 and 6). EA treatment (10 Hz, 1 mA) was applied at bilateral ST36 acupoints in rats once every other day on days 0–14. For sham EA, needles were inserted at ST36 acupoints without electrical stimulation. Mechanical allodynia was measured by mechanical withdrawal latency (MWL) of paws to a mechanical stimulus every 2 days. Protein expression of TLR4 and NF-κB p65, as well as TMEM119 and GFAP (indicators of microglia and astrocytes, respectively) in spinal cord was quantified by Western blot analysis. Levels of inflammatory cytokines IL-1β and TNF-α in spinal cord and serum were detected by ELISA.

Results

Mechanical allodynia induced by PTX in both paws (right and left) of rats was significantly attenuated by EA but not sham EA treatment. In addition, EA, but not sham EA, inhibited the activation of both microglia (TMEM119) and astrocytes (GFAP) in lumbar spinal cord. Moreover, Western blot analysis revealed that protein expression of TLR4 and NF-κB in spinal cord was suppressed by EA but not sham EA treatment. PTX significantly increased inflammatory cytokines in spinal cord and serum, which were ameliorated by EA treatment but not by sham EA.

Conclusion

These results indicate that EA treatment attenuates PTX-induced mechanical allodynia. The putative mechanism corroborating this finding could be related to the suppression of activated microglia and astrocytes in spinal cord, as well as the inhibition of the activated TLR4/NF-κB signaling pathway by EA treatment.

Two-Dimensional Second-Order Topological Insulator in Graphdiyne

A second-order topological insulator (SOTI) in d spatial dimensions features topologically protected gapless states at its (d-2)-dimensional boundary at the intersection of two crystal faces, but is gapped otherwise. As a novel topological state, it has been attracting great interest, but it remains a challenge to identify a realistic SOTI material in two dimensions (2D). Here, based on combined first-principles calculations and theoretical analysis, we reveal the already experimentally synthesized 2D material graphdiyne as the first realistic example of a 2D SOTI, with topologically protected 0D corner states. The role of crystalline symmetry, the robustness against symmetry breaking, and the possible experimental characterization are discussed. Our results uncover a hidden topological character of graphdiyne and promote it as a concrete material platform for exploring the intriguing physics of higher-order topological phases.

[Establishment and research of a New Zealand rabbit model of laryngopharyngeal reflux]

Objective: To establish a New Zealand rabbit animal model of laryngopharyngeal reflux disease (LPRD) using esophageal balloon together with metal internal stent dilation and to investigate the changes of mucosa. Methods: 20 New Zealand rabbits were randomly divided into experimental group and control group, with 10 in each group. Balloon dilatation and metal internal stent dilation were carried out in experimental group to reproduce the animal model of LPRD.The middle of balloon was placed at the lower esophageal sphincter (LES) while the stent was placed at the upper esophageal sphincter (UES). The guide wire was placed in the control group, but the balloon was not expanded and the stent was not placed. The general condition, pH value of hypopharynx, laryngeal histopathology and changes of pepsin content of New Zealand rabbits were observed regularly. The difference between experimental group and control group was compared. Results: The 24-hour Dx-pH monitoring results showed that the number of reflux episodes(20.0[9.5, 35.0], 13.0[6.5, 22.0]), and the percent time below pH 5.5 (1.36%[0.60%, 4.57%], 1.36%[0.43%, 2.77%]) in the experimental group at the 2nd and 4th week were significantly different from those in the control group (0[0,3.0], 1.0[0.5, 3.8]; 0[0, 0.01%], 0[0, 0], respectively, all P<0.01), suggesting that the experimental group New Zealand rabbits developed LPRD. Compared with the control group under microscope, lymphocytes infiltration and submucosal gland hyperplasia increased in the mucosa of the throat of the experimental group. The results of pepsin immunohistochemical staining between the two groups were statistically significant (P=0.014). Conclusion: The use of balloon dilatation of the LES combined with metal stent dilatation of the UES can successfully establish a laryngopharyngeal reflux model, and lesions in the throat tissue can be observed.