Intrinsic Triple Degeneracy Point Bounded by Nodal Surfaces in Chiral Photonic Crystal.

In periodic systems, band degeneracies are typically protected and classified by spatial symmetries. However, in photonic systems, the Γ point at zero frequency is an intrinsic degeneracy due to the polarization degree of freedom of electromagnetic waves. For chiral photonic crystals, such an intrinsic degeneracy carries ±2 chiral topological charge while having linear band dispersions, different from the general perception of charge-2 nodes being associated with quadratic dispersions. Here, we show that these topological characters originate from the spin-1 Weyl point at zero frequency node of triple degeneracy, due to the existence of an electrostatic flat band. Such a topological charge at zero frequency is usually buried in bulk band projections and has never been experimentally observed. To address this challenge, we introduce space-group screw symmetries in the design of chiral photonic crystal, which makes the Brillouin zone boundary an oppositely charged nodal surface enclosing the Γ point. As a result, the emergent Fermi arcs are forced to connect the projections of these topological singularities, enabling their experimental observation. The number of Fermi arcs then directly reveals the embedded topological charge at zero frequency.

[Analysis of the efficacy and safety of CT-guided radiofrequency ablation of posterior root of the spinal nerve in the treatment of postherpetic neuralgia].

Objective: To investigate the efficacy and safety of CT-guided radiofrequency ablation of posterior root of spinal nerve in the treatment of postherpetic neuralgia (PHN). Methods: A total of 102 PHN patients (42 males and 60 females) aged (69.7±9.4) years who underwent CT-guided radiofrequency ablation of posterior root of spinal nerve in the Department of Pain Medicine of the Affiliated Hospital of Jiaxing University from January 2017 to April 2020 were retrospectively included. Patients were followed up, and numerical rating scale (NRS) score, Pittsburgh sleep quality index (PSQI), satisfaction score and complications before surgery (T0) and at 1 d (T1), 3 months (T2), 6 months (T3), 9 months (T4) and 12 months (T5) after surgery were recorded. Results: The NRS score of PHN patients at T0, T1, T2, T3, T4, and T5 [M(Q1, Q3)] was 6(6, 7), 2(2, 3), 3(2, 4), 3(2, 4), 2(1, 4), 2(1, 4), respectively. Likewise, the PSQI score [M(Q1, Q3)] at aforementioned time points was 14(13, 16), 4(3, 6), 6(4, 8), 5(4, 6), 4(2, 8), 4(2, 9), respectively. Compared with T0, the NRS and PSQI scores at all time points from T1 to T5 were lower, with statistically significant differences (all P<0.001). The overall effective rate of surgery at 1 year postoperatively was 71.6% (73/102) with a satisfaction score of 8(5, 9), and the recurrence rate was 14.7% (15/102) with a recurrence time of (7.5±0.8) months. The main postoperative complication was numbness, with an incidence of 86.0% (88/102), and the degree of numbness gradually decreased with time. Conclusion: CT-guided radiofrequency ablation of posterior root of spinal nerve for PHN has a high effective rate and a low recurrence rate, with high safety profile, and may be a feasible surgical option for the treatment of PHN.

[Exploration of the effect of blood lipids on the lesion distribution pattern in acute ischemic stroke based on MRI study with population standard spatial analysis].

Objective: To explore the effect of blood lipids on the lesion distribution pattern in patients with acute ischemic stroke by using MRI technology based on population standard spatial analysis. Methods: The MRI data of 1 202 patients with acute ischemic stroke in General Hospital of Eastern Theater Command from January 2015 to December 2020 and Nanjing First Hospital from January 2013 to December 2021 were retrospectively collected, including 871 males and 331 females, aged 26 to 94 (64±11) years. According to the condition of blood lipids, they were divided into the dyslipidemia group (n=683) and the normal blood lipids group (n=519). After the automatic segmentation of diffusion-weighted imaging (DWI) images by artificial intelligence, the infarct sites were registered to the standard space which was used to draw the frequency heat map. The chi-square test was used to compare the difference in lesion location between the two groups. Generalized linear model regression analysis was used to observe the correlation between each blood lipid index and lesion site, and inter-group comparison and correlation analysis were used to observe the relationship between each blood lipid index and lesion volume. Results: Compared with the normal blood lipid group, the lesions in the dyslipidemia group were more extensive, mostly distributed in the occipital temporal region of the right posterior cerebral artery and the frontal region of the left middle cerebral artery. The brain regions of higher triglyceride(TG) and higher low-density lipoprotein cholesterol(LDL-C) groups were concentrated in the posterior circulation. The brain regions in the higher total cholesterol(TC) and lower high-density lipoprotein cholesterol(HDL-C) groups were concentrated in the anterior circulation(all P<0.05). In the anterior circulation infarct volume, the higher TC group was significantly higher than the normal TC group[(27.58±5.34) vs (17.73±1.18)ml, P=0.029]. In the posterior circulation infarct volume, the higher LDL-C group and the TG group were significantly higher than the normal LDL-C and TG groups[(7.55±2.51) vs (3.55±0.31) ml; (5.76±1.19) vs (3.36±0.30) ml](both P<0.05). Correlation analysis showed that TC and LDL-C were non-linearly (U-shaped) correlated with anterior circulation infarct volume (both P<0.05). Conclusions: Different blood lipids have effects on the distribution pattern and volume of ischemic stroke infarcts. Different hyperlipidemia is related to the specific distribution site and the larger extent of infarction.

[Clinical and neuroelectrophysiological characteristics of primary peripheral nerve hyperexcitability syndrome].

Objective: To investigate the clinical and neuroelectrophysiological characteristics of patients with primary peripheral nerve hyperexcitability syndrome (PNHS). Methods: The clinical data of 20 patients who were diagnosed with PNHS in Beijing Tiantan Hospital from April 2016 to January 2023 were retrospectively collected. All patients underwent neuroelectrophysiological examinations. Clinical and electrophysiological characteristics were compared between the antibody positive and antibody negative groups, according to serum and cerebrospinal fluid anti-contactin-associated protein-like 2 (CASPR2) and/or anti-leucine-rich glioma-inactivated protein 1 (LGI-1) antibodies. Results: There were 12 males and 8 females, with a mean age of (44.0±17.2) years and the disease course of [M (Q1, Q3)] 2.3 (1.1, 11.5) months. Motor symptoms included fasciculations, myokymia, muscle pain, cramps, and stiffness. These symptoms were commonly seen in the lower limbs (17 patients), followed by upper limbs (11 patients), face (11 patients) and trunk (9 patients). Nineteen (19/20) patients had sensory abnormalities and/or autonomic dysfunction, 13 patients had central nervous system involvement, and 5 patients had concomitant lung cancer or thymic lesions. The characteristic spontaneous potentials on needle electromyography (EMG) were myokymia potential (19 patients), fasciculation potential (12 patients), spastic potential (3 patients), neuromyotonic potential (1 patients), etc, which were commonly seen in the lower limb muscles, especially the gastrocnemius muscle(12 patients). After-discharge potential was found in 8 patients, and 7 were in the tibial nerve. Seven patients had positive serum anti-CASPR2 antibodies, and 3 of them had concomitant anti-LGI1 antibodies. And 1 patient had positive serum anti-LGI1 antibody alone. Compared with patients in the antibody negative group (n=12), the patients who had anti-VGKC complex antibodies (n=8) had a shorter course of disease [M (Q1, Q3): 1.8 (1, 2) months vs 9.5 (3.3, 20.3) months, P=0.012], higher incidence of after-discharge potential (6/8 vs 2/12, P=0.019). The immunotherapy regimen (multi-dru, single-drug, no immunotherapy: 6, 2, 0 patients) in antibody-positive patients was different from the antibody-negative group (3, 6, 3 patients, U=21.00, P=0.023). Conclusions: The symptoms of motor nerve hyperexcitation, characteristic EMG spontaneous potentials and after-discharge potentials in PNHS patients are most commonly seen in the lower limbs. Attention should be paid to concomitant sensory and autonomic nerve hyperexcitation. PNHS patients with positive serum anti-CASPR2 antibodies may require immunotherapy with multiple drugs.

[Predictive performance for prognosis of aneurysmal subarachnoid hemorrhage with ventricular hemorrhage by imaging combined with clinical and laboratory quantitative index model].

Objective: To explore the predictive performance of image quantitative index model, clinical-laboratory index model and image-clinical multi-dimensional fusion model in predicting the prognosis of patients with aneurysmal subarachnoid hemorrhage (aSAH) with intraventricular hemorrhage (IVH). Methods: A total of 349 patients with aSAH and IVH, including 122 males and 227 females, aged 22 to 85 (59±11) years underwent CT scan in the General Hospital of Eastern Theater Command from January 2010 to December 2019 were used as dataset 1 to construct a prognostic model. A prognostic model was constructed for data set 1, and the functional recovery of patients 12 months after discharge was evaluated using the modified Rankin Scale (mRS). According to the results, those patients were divided into two groups: good outcome group (n=267) and poor outcome group (n=82). In addition, 63 aSAH patients with IVH, including 27 males and 36 females, aged 32 to 87 (61±12) years who were admitted to the General Hospital of Eastern Theater Command from January 2020 to December 2021 were collected as dataset 2 for independent verification of the model, including 30 patients with poor prognosis. Clinical information (age and gender), laboratory indicators (blood routine and blood biochemistry), and imaging quantitative indicators (such as volume, density, shape of each ventricle hemorrhage area outlined and extracted on head CT scan etc.) were recorded for all patients (dataset 1 and 2). The clinical, laboratory and imaging quantitative indicators of dataset 1 were screened by using L1 regularization and multiple logistic regression method was used to construct the clinical-laboratory index model, image quantitative index model and image-clinical multi-dimensional fusion model, according to the weight coefficient of features in the clinical-laboratory index model and image quantitative index model, screen out the main features. The model was trained and internally validated by 5-fold cross-validation. The model was validated independently in dataset 2. Results: The AUC (area under the ROC curve) of clinical-laboratory index model, image quantitative index model and multidimensional fusion model constructed based on dataset 1 were 0.75 (95%CI: 0.69-0.81), 0.68 (95%CI: 0.61-0.74) and 0.86 (95%CI: 0.82-0.91). The Delong test showed that there were statistically significant differences between the performance of the multi-dimensional fusion model and the clinical-laboratory index model or image quantitative index model (all P<0.05). The AUC of clinical-laboratory index model, image quantitative index model and multidimensional fusion model of dataset 2 were 0.79 (95%CI: 0.68-0.91), 0.70 (95%CI: 0.57-0.83) and 0.81 (95%CI: 0.70-0.92). In addition, in the clinical-laboratory index model and imaging quantitative index model constructed based on data 1, age, Hunt-Hess grade on admission, Neutrophil/Lymphocyte (N/L) (the weight coefficients in the clinical-laboratory index model were 1.00, -0.59 and 0.44) and the standard deviation of third ventricle hemorrhage density, minimum hemorrhage density of the fourth ventricle, and left ventricle hemorrhage sphericity (the weight coefficients in the image quantitative index model were -1.00, 0.85 and -0.84) were the main features of the screening. Conclusions: Quantitative imaging indicators of ventricular hemorrhage (standard deviation of third ventricular hemorrhage density, minimum density of fourth ventricular hemorrhage, and left ventricular sphericity) are helpful to predict the poor prognosis of patients with aSAH with ventricular hemorrhage. Dimensional fusion model has greater value in predicting poor prognosis of patients.

[Revision rate of periprosthetic joint infection post total hip or knee arthroplasty of 34 hospitals in China between 2015 and 2017: a multi-center survey].

Objective: To investigate the rate of periprosthetic joint infection (PJI) revision surgeries and clinical information of hip-/knee- PJI cases nationwide from 2015 to 2017 in China. Methods: An epidemiological investigation. A self-designed questionnaire and convenience sampling were used to survey 41 regional joint replacement centers nationwide from November 2018 to December 2019 in China. The PJI was diagnosed according to the Musculoskeletal Infection Association criteria. Data of PJI patients were obtained by searching the inpatient database of each hospital. Questionnaire entries were extracted from the clinical records by specialist. Then the differences in rate of PJI revision surgery between hip- and knee- PJI revision cases were calculated and compared. Results: Total of 36 hospitals (87.8%) nationwide reported data on 99 791 hip and knee arthroplasties performed from 2015 to 2017, with 946 revisions due to PJI (0.96%). The overall hip-PJI revision rate was 0.99% (481/48 574), and it was 0.97% (135/13 963), 0.97% (153/15 730) and 1.07% (193/17 881) in of 2015, 2016, 2017, respectively. The overall knee-PJI revision rate was 0.91% (465/51 271), and it was 0.90% (131/14 650), 0.88% (155/17 693) and 0.94% (179/18 982) in 2015, 2016, 2017, respectively. Heilongjiang (2.2%, 40/1 805), Fujian (2.2%, 45/2 017), Jiangsu (2.1%, 85/3 899), Gansu (2.1%, 29/1 377), Chongqing (1.8%, 64/3 523) reported relatively high revision rates. Conclusions: The overall PJI revision rate in 34 hospitals nationwide from 2015 to 2017 is 0.96%. The hip-PJI revision rate is slightly higher than that in the knee-PJI. There are differences in revision rates among hospitals in different regions.

[Factors influencing bilirubin elevation and its correlation with UGT1A1 gene polymorphism in the early postoperative period of transjugular intrahepatic portosystemic shunt].

Objective: To investigate the factors influencing total bilirubin elevation and its correlation with UGT1A1 gene polymorphism in the early postoperative period of transjugular intrahepatic portosystemic shunt (TIPS). Methods: 104 cases with portal hypertension and esophageal variceal hemorrhage (EVB) treated with elective TIPS treatment were selected as the study subjects and were divided into a bilirubin-elevated group and a normal bilirubin group according to the total bilirubin elevation level during the early postoperative period. Univariate analysis and logistic regression were used to analyze the factors influencing total bilirubin elevation in the early postoperative period. PCR amplification and first-generation sequencing technology were used to detect the polymorphic loci of the UGT1A1 gene promoter TATA box, enhancer c.-3279 T > G, c.211G > A, and c.686C > A. Logistic regression was used to analyze the correlation of four locus alleles and genotypes with elevated total bilirubin in the early postoperative period. Results: Among the 104 cases, 47 patients were in the bilirubin elevated group, including 35 males (74.5%) and 12 females (25.5%), aged (50.72 ± 12.56) years. There were 57 cases in the normal bilirubin group, including 42 males (73.7%) and 15 females (26.3%), aged (51.63 ± 11.10) years. There was no statistically significant difference in age (t = -0.391, P = 0.697) and gender (χ(2) = 0.008, P = 0.928) between the two groups of patients. Univariate analysis revealed that preoperative alanine transaminase (ALT) level (χ(2) = 5.954, P = 0.015), total bilirubin level (χ(2) = 16.638, P < 0.001), MELD score (χ(2) = 10.054, P = 0.018), Child-Pugh score (χ(2) = 6.844, P = 0.022), and postoperative portal vein branch development (χ(2) = 6.738, P = 0.034) were statistically significantly different between the two groups. Logistic regression analysis showed that preoperative ALT level, total bilirubin level, and portal vein branch development after TIPS were correlated with the elevated total bilirubin in the early postoperative period. The polymorphism of the c.211G > A locus of the UGT1A1 gene correlation had elevated total bilirubin in the early postoperative period of TIPS. The risk of elevated total bilirubin was increased in the population carrying allele A (P = 0.001, OR = 4.049) in the early postoperative period. Allelic polymorphisms in the TATA box promoter region and enhancer c.-3279 T > G and c.686C > A had no statistically significant difference between the bilirubin-elevated group and the normal bilirubin group. Conclusion: The preoperative ALT level, total bilirubin level, and portal vein branch development are correlated with the elevated total bilirubin in early postoperative patients. The polymorphisms of the UGT1A1 gene and enhancer c.211G > A are correlated with the occurrence of elevated total bilirubin in the early postoperative period of TIPS. Allele A carrier may have a higher risk of elevated total bilirubin in the early postoperative period.

Straight Photonic Nodal Lines with Quadrupole Berry Curvature Distribution and Superimaging "Fermi Arcs".

In periodic systems, nodal lines are loops in the three-dimensional momentum space with each point on them representing a band degeneracy. Nodal lines exhibit rich topological features, as they can take various configurations such as rings, links, chains, and knots. These line nodes are generally protected by mirror or PT symmetry and frequently accompanied by drumhead surface states. Here, we propose and demonstrate a novel type of photonic straight nodal lines in a D_{2D} metacrystal, which are protected by an unusual rotoinversion time (roto-PT) symmetry. These nodal lines are located at the central axis and hinges of the Brillouin zone. They appear as quadrupole sources of Berry curvature flux in contrast to the Weyl points, which are monopoles. Interestingly, topological surface states exist at all three cutting surfaces, as guaranteed by π-quantized Zak phases along all three directions. As frequency changes, the surface state equifrequency contours evolve from closed to open and become straight lines at a critical transition frequency, at which diffractionless surface wave propagations are experimentally demonstrated, paving the way toward development of superimaging topological devices.

Observation of Non-Abelian Charged Nodes Linking Nonadjacent Gaps.

Nodal links are special configurations of band degeneracies in the momentum space, where nodal line branches encircle each other. In PT symmetric systems, nodal lines can be topologically characterized using the eigenvector frame rotations along an encircling loop and the linking structure can be described with non-Abelian frame charges involving adjacent bands. While the commutation rules between the frame charges are well established, the underlying relationship between distant band gap closing nodes remains to be explored. In this Letter, we present a photonic multiple nodal links system, where the nodal lines of nonadjacent bands are investigated with symmetry constraints on frame charges. Through an orthogonal nodal chain, the nodal line from the lower two bands predicts the existence of nodal lines formed between the higher bands. We designed and fabricated a metamaterial, with which the multiple nodal links and the topological connection between nonadjacent nodal lines are experimentally demonstrated.

Design and optical performance research of a fully customizable collimating lens based on total internal reflection.

An optical design method of a fully customizable collimating lens is proposed. The initial model of the complete lens is constructed by two parts. One part is calculated by the total internal reflection algorithm; the other part is constructed by trial-and-error method. The lens is further optimized by normal vector correction and high- and low-angle compensation. The optical performance of the fully customizable collimating lens is studied. It is proven to have good collimation performance with a divergence angle of 1.8° at 50% of the maximum luminous intensity; the uniformity is as high as 98.4%.