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Here, Ca5Mn4−xNixV6O24 (CMNVO, x = 0.00–0.08) ceramics are successfully prepared by the solid-phase reaction method, and the connection between the physical phase information, microscopic morphology, Raman spectroscopy, and microwave dielectric properties is explored. The experimental results show that Ni2+ occupies the Mn2+ sites without altering the crystal structure and is effectively solid-solvated into the lattice. The relative density reaches a maximum value of 95.9% when the temperature (Tem.) = 900°C and x = 0.06. The trend of the dielectric constant (εr) depends on the ionic polarization rate, and the quality factor (Q×f values) are correlated with the microstructure and relative density. The maximum value of 43,800 GHz is reached at Tem. = 900°C and x = 0.06, and the temperature coefficient of resonant frequency (τf values) is enhanced from −75 ppm/°C to −52 ppm/°C. The CMNVO (x = 0.06) ceramic obtains better microwave dielectric properties (εr = 11.4, Q×f = 43,800 GHz, and τf = −52 ppm/°C). This ceramic material is expected to be a candidate for low-temperature co-fired ceramic (LTCC) microwave devices. [ABSTRACT FROM AUTHOR]

The chromosome 20 long arm (20q) is one of the genomic hotspots where copy number alterations frequently occur in multiple types of tumors. However, it remains elusive which genes are implicated in 20q-related tumorigenesis. Here, by querying TCGA and GEO databases, we observed frequent copy number amplification at 20q and the chromosome subband 20q13.33 was amplificated in multiple cancers. Among those genes at 20q13.33, PSMA7 was found with the strongest correlation with cancers. Further analysis revealed that PSMA7 amplification was the most frequent genetic alteration event conferring adverse prognosis in various cancers. Consistent with the strong positive correlation between PSMA7 amplification and gene expression, elevated PSMA7 expression was observed in 20 of 33 types of cancers with a close link to adverse outcomes in certain tumors. In addition, PSMA7 was essential for the growth of almost 1095 cancer lines. Mechanistically, aberrant PSMA7 most probably influenced the proteasome and protease-related pathways to promote tumorigenesis and might be antagonized by several compounds, e.g., Docetaxel in relevant cancers. The current in-depth pan-cancer analysis refines our understanding of the crucial oncogenic role of copy number amplifications at PSMA7 loci at the novel chromosome amplicon 20q13.33 across different tumors. [ABSTRACT FROM AUTHOR]

Background: The metastatic lymph node (LN) ratio (LNR) has shown to be an important prognostic factor in various gastrointestinal malignancies. Nevertheless, the prognostic significance of LNR in gallbladder carcinoma (GBC) remains to be determined. Methods: From January 2007 to January 2018, 144 advanced GBC patients (T2–4 stages) who underwent curative surgery with at least 6 LNs retrieved were enrolled. Receiver operating characteristic (ROC) curve was performed to identify the optimal cut-off value for LNR. The clinicopathological features stratified by LNR level were analyzed. Meanwhile, univariate and multivariate Cox regression proportional hazard models were performed to identify risk factors for overall survival (OS). Results: The optimal cut-off point for LNR was 0.28 according to the ROC curve. LNR>0.28 was associated with higher rate of D2 LN dissection (P=0.004) and higher tumor stages (P<0.001). Extent of liver resection, extrahepatic bile duct resection, tumor stage, LNR, margin status, tumor differentiation, and perineural invasion were associated with OS in univariate analysis (all P<0.05). GBC patients with LNR≤0.28 had a significantly longer median OS compared to those with LNR>0.28 (27.5 vs 18 months, P=0.004). Multivariate analysis indicated that tumor stage (T2 vs T3/T4; hazard ratio (HR) 1.596; 95% confidence interval (CI) 1.195–2.132), LNR (≤0.28 vs >0.28; HR 0.666; 95% CI 0.463–0.958), margin status (R0 vs R1; HR 1.828; 95% CI 1.148–2.910), and tumor differentiation (poorly vs well/moderately; HR 0.670; 95% CI 0.589–0.892) were independent prognostic factors for GBC (all P<0.05). Conclusions: LNR is correlated to advanced GBC prognosis and is a potential prognostic factor for advanced GBC with at least 6 LNs retrieved. [ABSTRACT FROM AUTHOR]

Blumea balsamifera, a wooden plant belonging to the family Asteraceae, is a medicinal herb with anticancer, antiviral, and multiple pharmacological effects, which are believed to be caused by its essential oil. The essential oil from B. balsamifera is comprised of mono- and sesqui-terpenes as the majority. Unfortunately, this plant has been facing the challenge of resource shortage, which could be effectively alleviated by biological engineering. Therefore, the identification of key elements involved in the biosynthesis of active ingredients becomes an indispensable prerequisite. In this study, candidate genes encoding monoterpene synthase were screened by transcriptome sequencing combined with metabolomics profiling in the roots, stems, and leaves of B. balsamifera. Then, these candidates were successfully cloned and verified by heterologous expression and in vitro enzyme activity assays. As a result, six candidate BbTPS genes were isolated from B. balsamifera, of which three encoded single-product monoterpene synthases and one encoded a multi-product monoterpene synthase. Among them, BbTPS1, BbTPS3, and BbTPS4 could catalyze the formation of D-limonene, α-phellandrene, and L-borneol, respectively. Meanwhile, BbTPS5 functioned in catalyzing GPP into terpinol, β-phellandrene, β-myrcene, D-limonene, and 2-carene in vitro. In general, our results provided important elements for the synthetic biology of volatile terpenes in B. balsamifera, which laid a foundation for subsequent heterologous production of these terpenoids through metabolic engineering and increasing their yield, as well as promoting sustainable development and utilization of B. balsamifera. [ABSTRACT FROM AUTHOR]

To meet the polarization adaptation in communication systems, it is necessary to improve the performance of polarization converters. Microwave dielectric materials are very promising to optimize the response speed, operating frequency, conversion efficiency, and transmission stability of polarization converters, which puts higher demands on ceramic materials. In this paper, the microwave dielectric properties of Ca5Mn4(VO4)6 ceramics are improved by using Cu2+ instead of Mn2+. The effects of Cu2+ substitution and sintering temperature on microwave dielectric properties are also investigated. The substituted ceramics have excellent microwave dielectric properties of εr = 11.4, Q × f = 42709 GHz, and τf = − 65 ppm/°C. As a concept demonstration, a new 5G polarization converter between linear polarization and left-handed circularly polarized (LCP) waves is designed by using this ceramic substrate. By observing the surface electric field and surface current, it can be judged that the principle of the polarization converter is the difference in the electric dipole resonance absorption between the LCP and the right-handed circularly polarized (RCP) waves. The simulation results of normalized reflectivity and far-field (electric field and phase) show good performance of the polarization converter. [ABSTRACT FROM AUTHOR]

Background: Minimally invasive surgery for perihilar cholangiocarcinoma (pCCA) is in an exploratory phase by now and is only recommended for carefully selected patients. Patients and Methods: Our team performed total laparoscopic hepatectomy in a 64-year-old woman with perihilar cholangiocarcinoma type IIIb. Laparoscopic left hepatectomy and caudate lobectomy were performed involving a no-touch en-block technique. Meanwhile, extrahepatic bile duct resection, radical lymphadenectomy with skeletonization, and biliary reconstruction were performed. Results: Laparoscopic left hepatectomy and caudate lobectomy were successfully performed in 320 min with 100 ml of blood loss. The histological grading was T2bN0M0 (stage II). The patient was discharged on the 5th day without postoperative complications. Following the operation, the patient received single-drug capecitabine chemotherapy. There was no recurrence after 16 months of follow-up. Conclusion: Our experience is that, in selected patients with pCCA type IIIb or type IIIa, laparoscopic resection can reach comparable outcome to open surgery with standardized lymph node dissection by skeletonization, use of no-touch en-block technique, and proper digestive tract reconstruction. [ABSTRACT FROM AUTHOR]

Background: Enhanced recovery after surgery (ERAS) is a multidisciplinary, stress-minimizing approach that is associated with improved postoperative outcomes. However, whether the level of compliance with ERAS protocols impacts the postoperative outcome of patients with primary liver cancer undergoing liver resection is unknown. The study aimed to analyze the association between compliance with ERAS protocols and liver resection outcomes. Methods: This prospective cohort study consecutively recruited patients with primary liver cancer who were scheduled for elective liver surgery between January 2019 and December 2020 at the Department of Biliary Surgery, West China Hospital of Sichuan University. Twenty individual ERAS items were assessed in all patients. The patients were divided into two groups according to their degree of compliance with the ERAS interventions: an ERAS-compliant (ERAS-C) group of individuals who complied with over 75% of the ERAS components and an ERAS-noncompliant (ERAS-N) group. The primary outcomes were ERAS compliance, occurrence of major complications within 30 days postoperatively, and length of postoperative hospital stay. The secondary outcomes were 30-day readmissions, reoperations and other rehabilitation indicators. The study was registered at www.chictr.org.cn (identity number ChiCTR2000040021). Results: Overall, 436 patients were enrolled; their mean age was 54 years (interquartile range [IQR], 47–66). Of these patients, 206 were allocated to the ERAS-C group, and the other 230 patients comprised the ERAS-N group. The overall compliance rate was 70% (IQR, 65%-80%). The ERAS-C group had higher compliance rates [80.00% (IQR, 75.00–85.00%)] than the ERAS-N group [65.00% (IQR, 65.00–70.00%)], P < 0.001). The ERAS-C group had significantly fewer major complications (7.77% vs. 15.65%, OR, 0.449, 95% CI, 0.241–0.836, P = 0.012) and shorter postoperative hospital stays (5 days [IQR, 4–6] vs. 6 days [IQR, 5–7], P < 0.001) than the ERAS-N group. Subgroup analysis indicated that compliance rates greater than 80%, between 65 and 80%, and lower than 65% were associated with decreased major complication rates (6.25%, 8.48% and 22.83%, respectively) and shorter postoperative hospital stays. However, the rates of ICU stay, readmission, reoperation and mortality within 30 days after surgery were not different between groups (P > 0.05). Conclusion: The results of this study suggest that higher compliance with ERAS components is associated with a lower incidence of major postoperative complications and a shorter postoperative hospital stay. [ABSTRACT FROM AUTHOR]

With the development of modern communication technology, all kinds of wireless communication devices are developing rapidly toward miniaturization, lightweight, and integration, which puts forward higher requirements for the size and volume of the antenna. In recent years, magneto-dielectric ferrite materials have been widely studied because of their good performance in magnetic and dielectric properties. In this work, a series of Ba1.5Sr1.5Co2−xFe24+xO41 (x = 0, 0.2, 0.4, 0.6) materials were successfully synthesized through the traditional solid-state reaction method. The influences of Fe substitution on the phase formation, microstructure, high-frequency dielectric, and magnetic properties were studied. It is found that, with the increase of substitution amount, the real permeability decreases from 8.8 to 4.2, and the real permittivity increases from 7.6 to 9.8. When the amount of substitution is relatively low (x = 0, 0.2), the real permeability and permittivity of the materials are almost equivalent at the frequency of 500 MHz to 1.0 GHz. The sample of x = 0.2 with permeability (7.1 to 8.2) and permittivity (7.8), and low losses (tanδµ ≤ 0.22, tanδε ≤ 0.02) could be used for antenna miniaturization in UHF band in the future. [ABSTRACT FROM AUTHOR]

Terahertz absorbers based on doped silicon have achieved broadband and high-efficiency absorption due to their high concentration of carriers. However, their tunable performance is obviously insufficient. Here, we propose a new scheme for active terahertz absorption based on undoped silicon with a metamaterial antireflection layer, which realizes both strong absorption and ultrahigh modulation depth. Benefiting from the weak absorption and high transmission of undoped silicon for 1064-nm continuous wave, uniformly distributed carriers across the entire thickness of the absorber are excited, and efficient free carrier absorption of the terahertz wave is obtained. We use only a 500-μm thick absorber and achieve absorption greater than 90% in the range of 0.58 to 1.92 THz, with a peak value of 99%. More important, the absorber can be switched between two working states of nonabsorption and high-efficiency absorption by changing the pump power, which means the modulation depth reaches 100%. This simple and high-performance implementation scheme provides a new idea for the design of terahertz tunable absorbers. [ABSTRACT FROM AUTHOR]

Sausage waves have been frequently reported in solar magnetic structures such as sunspots, pores, and coronal loops. However, they have not been unambiguously identified in photospheric bright points (BPs). Using high-resolution TiO image sequences obtained with the Goode Solar Telescope at the Big Bear Solar Observatory, we analyzed four isolated BPs. It was found that their area and average intensity oscillate for several cycles in an in-phase fashion. The oscillation periods range from 100 to 200 seconds. We interpreted the phase relation as a signature of sausage waves, particularly slow waves, after discussing sausage-wave theory and the opacity effect. [ABSTRACT FROM AUTHOR]

The introduction of "metamaterials" has had a profound impact on several fields, including electromagnetics. Designing a metamaterial's structure on demand, however, is still an extremely time-consuming process. As an efficient machine learning method, deep learning has been widely used for data classification and regression in recent years and in fact shown good generalization performance. We have built a deep neural network for on-demand design. With the required reflectance as input, the parameters of the structure are automatically calculated and then output to achieve the purpose of designing on demand. Our network has achieved low mean square errors (MSE), with MSE of 0.005 on both the training and test sets. The results indicate that using deep learning to train the data, the trained model can more accurately guide the design of the structure, thereby speeding up the design process. Compared with the traditional design process, using deep learning to guide the design of metamaterials can achieve faster, more accurate, and more convenient purposes. [ABSTRACT FROM AUTHOR]

Background: Benign biliary stricture (BBS) is highly refractory. Currently, there is no effective strategy for prevention of BBS recurrence. The aim of this study is to establish a novel BBS rabbit model and to investigate the efficacy of biliary infusion with anti-proliferative medications for treating BBS.Method: A BBS model was established via surgical injury and biliary infection. The biliary infusion tube was inserted into the common bile duct via the stump of cystic duct after cholecystectomy. Biliary infusions with Rapamycin, Pirfenidone and Fasudil were performed daily during the 4 weeks following the surgery. The wall thickness and luminal area of the bile duct were assessed.Results: All rabbits formed BBS after surgery. The mortality rate was 13% (8/60) and tube withdrawal rate was 4% (2/48). The thickness of the bile duct wall was significantly reduced; whereas the luminal area of the bile duct was dramatically enlarged in the Rapamycin or the Pirfenidone treated group, compared to the saline treated group. Furthermore, the local treatment significantly decreased the levels of proliferation makers, including PCNA, Collagen I and fibrogenic mediators, including ACTA2 and TGF-beta.Conclusion: We have established a novel animal model for BBS formation. We have further demonstrated that biliary infusion with Rapamycin or Pirfenidone limits the biliary strictures through inhibiting the proliferation of the bile duct wall in this model. This may represent a new avenue for preventing biliary restenosis. [ABSTRACT FROM AUTHOR]

The original version of the article unfortunately contained an error in funding information. This has been corrected with this erratum. [ABSTRACT FROM AUTHOR]