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Background: The Node Reporting and Data System (Node-RADS) is a recently proposed classification system for the categorization of lymph nodes in radiological images. This study was conducted to retrospectively evaluate the diagnostic accuracy of the Node-RADS score for metastatic cervical lymph nodes on magnetic resonance imaging (MRI) of patients with nasopharyngeal carcinoma (NPC). Methods: We retrospectively analyzed cervical lymph nodes of NPC cases. Two radiologists independently evaluated each lymph node on the MRI scans using Node-RADS. Interobserver agreement between 2 radiologists for Node-RADS score assessment was evaluated by linear weighted kappa statistics. The correlation between metastasis and the Node-RADS score of each lymph node was analyzed using multivariate regression analysis. To investigate the diagnostic performance of the Node-RADS score, we further conducted receiver operating characteristic curve analysis. Correspondently, the sensitivity, specificity, positive predictive value, and negative predictive value of each different cutoff (>1, >2, >3, and >4) were computed. Results: In all, 119 patients with NPC were assessed, including 203 cervical lymph nodes consisting of 140 (69%) of 203 metastatic and 63 (31%) of 203 benign. The kappa agreement between the 2 readers for the Node-RADS score was 0.863 (95% CI = 0.830-0.897, P <.001). Node-RADS score on MRI scan was shown to be an independent predictive factor of lymph node metastasis after multivariate regression analysis (odds ratio [OR] = 6.745, 95% CI = 3.964-11.474, P <.001). Node-RADS achieved an area under the curve (AUC) of 0.950 (95% CI = 0.921-0.979) in diagnosing metastatic lymph nodes. When Node-RADS >2 was identified as the best cutoff based on balanced values, the sensitivity and positive predictive value were 0.92 and 0.94, respectively. Conclusions: Our study suggests that the Node-RADS score has high accuracy in predicting NPC cervical lymph node metastasis. Nevertheless, this conclusion requires confirmation in a larger cohort of patients with NPC. [ABSTRACT FROM AUTHOR]

Colorectal cancer is the third most prevalent cancer worldwide, and its treatment has been a demanding clinical problem. Beyond traditional surgical therapy and chemotherapy, newly revealed molecular mechanisms diversify therapeutic approaches for colorectal cancer. However, the selection of personalized treatment among multiple treatment options has become another challenge in the era of precision medicine. Artificial intelligence has recently been increasingly investigated in the treatment of colorectal cancer. This narrative review mainly discusses the applications of artificial intelligence in the treatment of colorectal cancer patients. A comprehensive literature search was conducted in MEDLINE, EMBASE, and Web of Science to identify relevant papers, resulting in 49 articles being included. The results showed that, based on different categories of data, artificial intelligence can predict treatment outcomes and essential guidance information of traditional and novel therapies, thus enabling individualized treatment strategy selection for colorectal cancer patients. Some frequently implemented machine learning algorithms and deep learning frameworks have also been employed for long-term prognosis prediction in patients with colorectal cancer. Overall, artificial intelligence shows encouraging results in treatment strategy selection and prognosis evaluation for colorectal cancer patients. [ABSTRACT FROM AUTHOR]

The immunogenicity of SARS-CoV-2 vaccines is poor in kidney transplant recipients (KTRs). The factors related to poor immunogenicity to vaccination in KTRs are not well defined. Here, observational study demonstrated no severe adverse effects were observed in KTRs and healthy participants (HPs) after first or second dose of SARS-CoV-2 inactivated vaccine. Different from HPs with excellent immunity against SARS-CoV-2, IgG antibodies against S1 subunit of spike protein, receptor-binding domain, and nucleocapsid protein were not effectively induced in a majority of KTRs after the second dose of inactivated vaccine. Specific T cell immunity response was detectable in 40% KTRs after the second dose of inactivated vaccine. KTRs who developed specific T cell immunity were more likely to be female, and have lower levels of total bilirubin, unconjugated bilirubin, and blood tacrolimus concentrations. Multivariate logistic regression analysis found that blood unconjugated bilirubin and tacrolimus concentration were significantly negatively associated with SARS-CoV-2 specific T cell immunity response in KTRs. Altogether, these data suggest compared to humoral immunity, SARS-CoV-2 specific T cell immunity response are more likely to be induced in KTRs after administration of inactivated vaccine. Reduction of unconjugated bilirubin and tacrolimus concentration might benefit specific cellular immunity response in KTRs following vaccination. [ABSTRACT FROM AUTHOR]

This paper is concerned with the time‐dependent acoustic–elastic interaction problem associated with a bounded elastic body immersed in a homogeneous air or fluid above an unbounded rough surface. The well‐posedness and stability of the problem are first established by using the Laplace transform and the energy method. A perfectly matched layer (PML) is then introduced to truncate the interaction problem above a finite layer containing the elastic body, leading to a PML problem in a finite strip domain. We further establish the existence, uniqueness, and stability estimate of solutions to the PML problem. Finally, we prove the exponential convergence of the PML problem in terms of the thickness and parameter of the PML, based on establishing an error estimate between the DtN operators of the original problem and the PML problem. [ABSTRACT FROM AUTHOR]

In this paper, we propose and study the uniaxial perfectly matched layer (PML) method for three-dimensional time-domain electromagnetic scattering problems, which has a great advantage over the spherical one in dealing with problems involving anisotropic scatterers. The truncated uniaxial PML problem is proved to be well-posed and stable, based on the Laplace transform technique and the energy method. Moreover, the L2-norm and L∞-norm error estimates in time are given between the solutions of the original scattering problem and the truncated PML problem, leading to the exponential convergence of the time-domain uniaxial PML method in terms of the thickness and absorbing parameters of the PML layer. The proof depends on the error analysis between the EtM operators for the original scattering problem and the truncated PML problem, which is different from our previous work (Wei et al. [SIAM J. Numer. Anal.58 (2020) 1918–1940]). [ABSTRACT FROM AUTHOR]

Lycorine, a natural compound isolated from the traditional Chinese medicinal herb Lycoris radiata, exhibits multiple pharmacological effects, such as anti‐inflammatory, antiviral, and anticancer effects. Accumulating evidence also indicates that lycorine might hold the potential to treat age‐associated Alzheimer's disease. However, whether lycorine is involved in delaying the onset of cellular senescence and its underlying mechanisms has not been determined. Here, we demonstrate that the salt of lycorine, lycorine hydrochloride, significantly suppressed stress‐induced premature cellular senescence (SIPS) by ~2‐fold, as determined by senescence‐associated beta‐galactosidase (SA‐β‐gal) staining and the expression of p16 and p21. In addition, pretreating cells with lycorine hydrochloride significantly inhibited the expression of CXCL1 and IL1α, two factors of the senescence‐associated secreted phenotype (SASP) in SIPS cells. Further experiments revealed that lycorine hydrochloride promoted both the homologous recombination (HR) and nonhomologous end joining (NHEJ) pathways of DNA double‐strand break (DSB) repair. Mechanistic studies suggested that lycorine hydrochloride treatment promoted the transcription of SIRT1 and SIRT6, critical longevity genes positively regulating both HR and NHEJ repair pathways, thereby stimulating DSB repair and stabilizing genomes. Inhibiting SIRT1 enzymatic activity abrogated the protective effect of lycorine hydrochloride on delaying the onset of SIPS, repairing DSBs, and restoring genome integrity. In summary, our work indicates that lycorine hydrochloride might hold therapeutic potential for treating age‐associated diseases or promoting healthy aging by stabilizing genomes. [ABSTRACT FROM AUTHOR]

Living alone can cause social isolation and is correlated with multiple adverse health outcomes. Evidence about the association of living alone and social isolation with sarcopenia is limited. This meta-analysis aims to investigate the correlation between living alone, social isolation, and sarcopenia. According to the PRISMA guidelines, we systematically searched Medline, Embase, Web of Science, and Scopus for literature published up to June 30, 2023. We conducted reference checking to supplement the references. Two investigators independently screened the references for eligibility and assessed the quality of the references. We included references involving data on living alone, social isolation, and sarcopenia. Two investigators recorded study data for meta-analysis and study characteristics. Data regarding living alone and sarcopenia were available from 13 studies. Meta-analysis demonstrated that living alone is correlated with sarcopenia (odds ratio, 1.51; 95 % CI, 1.31–1.75; p < 0.001). The gender-stratified analysis demonstrated that women living alone are more likely to have sarcopenia (odds ratio, 1.81; 95 % CI, 1.32–2.48; p < 0.001) but not men (odds ratio, 1.24; 95 % CI, 0.56–2.74; p = 0.60). Data regarding social isolation and sarcopenia were available from five studies. Social isolation is also associated with sarcopenia (odds ratio, 1.70; 95 % CI, 1.51–1.92; p < 0.001). And subgroup analysis demonstrated that social isolation is a risk factor for sarcopenia (odds ratio, 1.79; 95 % CI, 1.55–2.06; p < 0.001). This meta-analysis revealed the association of living alone and social isolation with sarcopenia. Gender differences can help to screen high-risk groups of sarcopenia and reduce healthcare expenditures. As a further development of living alone, social isolation may play a more important role in sarcopenia than living alone. • Evidence of the association of living alone and social isolation with sarcopenia is limited. • Living alone is cross-sectionally correlated with sarcopenia. • Women living alone is more likely to have sarcopenia but not men. • Social isolation is cross-sectionally and longitudinally correlated with sarcopenia. [ABSTRACT FROM AUTHOR]

Understanding the influence of COVID-19 on China's agricultural economy and the Chinese government's emergency measures to ease the economic impacts of viral spread can offer urgently-needed lessons while this virus continues to spread across the globe. Thus, this study collected over 750,000 words upon the topic of COVID-19 and agriculture from the largest two media channels in China: WeChat and Sina Weibo, and employed web crawler technology and text mining method to explore the influence of COVID-19 on agricultural economy and mitigation measures in China. The results show that: (1) the impact of COVID-19 on China's agricultural economy at the very first phase is mainly reflected in eight aspects as crop production, agricultural products supply, livestock production, farmers' income and employment, economic crop development, agricultural products sales model, leisure agriculture development, and agricultural products trade. (2) The government's immediate countermeasures include resuming agricultural production and farmers' work, providing financial support, stabilizing agricultural production and products supply, promoting agricultural products sale, providing subsidies, providing agricultural technology guidance and field management, and providing assistance to poor farmers to reduce poverty. (3) The order of government's immediate countermeasures is not all in line with the order of impact aspects, which indicates that more-tailored policies should be implemented to mitigate the strikes of COVID-19 on China's agricultural economy in the future. [ABSTRACT FROM AUTHOR]

Abstract This paper considers the inverse problem of scattering of time-harmonic acoustic and electromagnetic plane waves by a bounded, inhomogeneous, penetrable obstacle with embedded objects inside. A new method is proposed to prove that the inhomogeneous penetrable obstacle can be uniquely determined from the far-field pattern at a fixed frequency, disregarding its contents. Our method is based on constructing a well-posed interior transmission problem in a small domain associated with the Helmholtz or modified Helmholtz equation and the Maxwell or modified Maxwell equations. A key role is played by the smallness of the domain which ensures that the lowest transmission eigenvalue is large so that a given wave number k is not an eigenvalue of the interior transmission problem. Another ingredient in our proofs is a priori estimates of solutions to the transmission scattering problems with data in L p (1 < p < 2), which are established in this paper by using the integral equation method. A main feature of the new method is that it can deal with the acoustic and electromagnetic cases in a unified way and can be easily applied to deal with inverse scattering by unbounded rough interfaces. [ABSTRACT FROM AUTHOR]

Starch accumulation in wheat endosperm has spatial differences. In this study, the accumulation, granule size distribution, physicochemical properties of starch in different spatial positions in wheat endosperm and response to nitrogen treatment were analysed. Results indicated that the starch content in the inner endosperm was higher than that in the outer endosperm. The total starch and amylose contents in the inner and outer endosperms decreased and increased after nitrogen treatment, respectively. The starch granules that accumulated in the inner endosperm were larger than those in the outer endosperm 10 days after anthesis. The amount of C-type starch granules in the inner endosperm was less than that in the outer endosperm, and nitrogen treatment increased the C-type starch granules in the inner endosperm. After nitrogen treatment, the short chains decreased, whereas the middle and long chains increased in the inner and outer endosperms. Nitrogen treatment also increased the crystal area in the inner and outer endosperms, especially the single helix in the inner endosperm. These conclusions provide new insights into the mechanism of starch accumulation in wheat endosperm and its response to the external environment. [Display omitted] • Endosperm separation technology was used to extract starch from the inner and outer endosperms. • Considerable differences in the distribution of starch granule size were observed in the inner and outer endosperms of wheat. • Nitrogen treatment reduced the starch content and increased the proportion of C-type starch granules in the inner endosperm. [ABSTRACT FROM AUTHOR]

In a two-layered medium, we prove that a buried inhomogeneous scatterer is uniquely determined from the wave field data measured in the upper half-space with respect to many incident point sources. Moreover, we extend the multilevel sampling method in Liu and Zou (2013) to numerically reconstruct the buried scatterer applying only few incident fields and partial scattered data. The extended recovery scheme only involves matrix–vector operations and does not need to solve any large-scale ill-posed linear systems or any optimization process. It is feasible to deal with the scatterers of different features and easy to implement, highly tolerant to noise and computationally quite cheap. We can regard it as an effective yet simple computational method to provide a reliable initial guess for the implementation in existing more accurate and refined optimization-type reconstruction algorithms. [ABSTRACT FROM AUTHOR]

Consider the inverse acoustic scattering of time-harmonic point sources by a locally perturbed interface with buried obstacles in the lower half-space. A novel version of the sampling method is proposed to simultaneously reconstruct the local perturbation of the rough interface and buried obstacles by constructing a modified near-field equation associated with a special rough surface, yielding a fast imaging algorithm. Numerical examples are presented to illustrate the effectiveness of the inversion algorithm. • A novel sampling method is proposed to simultaneously reconstruct the locally rough interface and buried obstacles. • The method relies on constructing a modified near-field equation associated with a special rough surface. • A fast imaging algorithm in frequencies is developed to reconstruct the interface and buried obstacles. • The algorithm is based on near-field data. [ABSTRACT FROM AUTHOR]

Abstract: Clinically, Parkinson's disease (PD)-related neuronal lesions commonly occur. The purpose of this study is to investigate potential therapeutic effect of curcumin against hippocampal damage of 6-hydroxydopamine (6-OHDA)-PD rat model. These results showed that curcumin significantly increased the body weight of 6-OHDA-impaired rats (P <0.01), and reversed the anhedonia in rats induced by 6-OHDA impairment (P <0.01). Meanwhile, behavioral manifestations of curcumin-treated PD rats were effectively ameliorated as shown in open field test (P <0.01). In addition, curcumin increased the contents of monoaminergic neurotransmitters (P <0.01), such as dopamine (DA) and norepinephrine (NE), in hippocampal homogenate through high performance liquid chromatography (HPLC) assay. Curcumin effectively alleviated the 6-OHDA-induced hippocampal damage as observed in hematoxylin–eosin (H&E) staining. Furthermore, curcumin obviously up-regulated hippocampal brain derived neurotrophic factor (BDNF), TrkB, phosphatidylinositide 3-kinases (PI3K) protein expressions, respectively as shown in Western blot analysis. These findings demonstrated that curcumin mediated the neuroprotection against 6-OHDA-induced hippocampus neurons in rats, which the underlying mechanism is involved in activating BDNF/TrkB-dependent pathway for promoting neural regeneration of hippocampal tissue. [Copyright &y& Elsevier]

Immunoglobulin A nephropathy (IgAN) has been well studied among young people, but few data on clinicopathological characteristics, treatment response and outcomes for elderly IgAN patients are available. A cohort study of elderly IgAN patients was performed. The combined endpoints of renal outcome were a 50% decline in eGFR compared with the time of renal biopsy, end-stage kidney disease and/or death. Risk factors associated with poor renal outcomes were then determined. The benefits of immunosuppressant therapies were also evaluated by Kaplan-Meier survival curve analysis. This study ultimately included 126 elderly patients with IgAN. Comparison between the endpoint and non-endpoint groups indicated that patients with poor outcomes had more severe clinical features, such as worse kidney function, severe hematuria and lower albumin levels. Cox regression analysis indicated that age (HR 1.15, 95% CI 1.02–1.29, p = 0.021), male gender (HR 9.71, 95% CI 1.00–97.56, p = 0.050), and urine red blood cells (HR 1.003, 95% CI 1.000–1.006, p = 0.029) were independent risk factors for poor renal outcome in elderly IgAN patients. To explore possible reasons accounting for the predictive value of age and sex, patients were divided into two groups based on these two variables. Patients in the geriatric group had lower serum albumin, estimated glomerular filtration rate, hemoglobin and aspartate aminotransferase levels than those in the quinquagenarian group. Male patients tended to have higher hemoglobin, higher alanine aminotransferase, and lower triglycerides and cholesterol levels than female patients. To investigate different treatment responses, patients were classified into two groups depending on treatment strategies (renin-angiotensin system inhibitors and immunosuppressive therapy), and the survival analysis indicated no significant difference in kidney outcome between the two groups (p > 0.05). This result still holds after adjusting for age, sex, eGFR, hematuria, and proteinuria. Advanced age, male, and hematuria might be independently associated with poor kidney outcomes in elderly patients with IgAN. Immunosuppressive therapy might confer no overall benefit to older IgAN patients. [ABSTRACT FROM AUTHOR]

This article is concerned with the problem of scattering of time-harmonic acoustic waves from an impenetrable periodic structure in a periodic layered medium. Having established the well-posedness of the direct problem by the integral equation method, we show that the measurements, corresponding to a countably infinite number of incident quasi-periodic waves above the structure, uniquely determine both the penetrable periodic interface and the impenetrable periodic structure together with its physical property. To this end, an important role is played by a priori estimates of the solution and a mixed reciprocity relation for the direct problem. [ABSTRACT FROM AUTHOR]

This article is concerned with uniqueness for reconstructing a periodic inhomogeneous medium sitting on a perfectly conducting plate. We deal with the problem in the framework of time-harmonic Maxwell systems without TE or TM polarization. An orthogonal relation is obtained for two refractive indices and then used to prove that the refractive index can be uniquely identified from a knowledge of the incident fields and the total tangential electric field on a plane above the inhomogeneous medium, utilizing the eigenvalues and eigenfunctions of a quasi-periodic Sturm-Liouville eigenvalue problem. [ABSTRACT FROM AUTHOR]

Background: Cancer is a leading global cause of death. Conventional cancer treatments like surgery, radiation, and chemotherapy have associated side effects. Ferroptosis, a nonapoptotic and iron-dependent cell death, has been identified and differs from other cell death types. Research has shown that ferroptosis can promote and inhibit tumor growth, which may have prognostic value. Given the unclear role of ferroptosis in cancer biology, this meta-analysis aims to investigate its impact on cancer prognosis. Methods: This systematic review and meta-analysis conducted searches on PubMed, Embase, and the Cochrane Library databases. Eight retrospective studies were included to compare the impact of ferroptosis inhibition and promotion on cancer patient prognosis. The primary endpoints were overall survival (OS) and progression-free survival (PFS). Studies lacking clear descriptions of hazard ratios (HR) and 95% confidence intervals for OS and PFS were excluded. Random-effects meta-analysis and meta-regression were performed on the included study data to assess prognosis differences between the experimental and control groups. Meta-analysis results included HR and 95% confidence intervals. This study has been registered with PROSPERO, CRD 42023463720 on September 27, 2023. Results: A total of 2,446 articles were screened, resulting in the inclusion of 5 articles with 938 eligible subjects. Eight studies were included in the meta-analysis after bias exclusion. The meta-analysis, after bias exclusion, demonstrated that promoting ferroptosis could increase cancer patients' overall survival (HR 0.31, 95% CI 0.21–0.44) and progression-free survival (HR 0.26, 95% CI 0.16–0.44) compared to ferroptosis inhibition. The results showed moderate heterogeneity, suggesting that biological activities promoting cancer cell ferroptosis are beneficial for cancer patient's prognosis. Conclusions: This systematic review and meta-analysis demonstrated that the promotion of ferroptosis yields substantial benefits for cancer prognosis. These findings underscore the untapped potential of ferroptosis as an innovative anti-tumor therapeutic strategy, capable of addressing challenges related to drug resistance, limited therapeutic efficacy, and unfavorable prognosis in cancer treatment. Registration: CRD42023463720. [ABSTRACT FROM AUTHOR]

Novel BaCa2M3O9 (M = Si, Ge) microwave dielectric ceramics were prepared via solid‐state reaction with sintering at 1125°C–1275°C for 5 h. Single‐phase BaCa2M3O9 (M = Si, Ge) ceramics were obtained according to stoichiometry. The single‐phase BaCa2Ge3O9 ceramic was confirmed through Rietveld refinement and high‐resolution transmission electron microscopy/selected area electron diffraction and synthesized for the first time. The BaCa2M3O9 (M = Si, Ge) exhibited a triclinic structure with a P1¯$\bar 1$ space group and good microwave dielectric properties. The εr, Q × f, and τf values of BaCa2M3O9 (M = Si, Ge) ceramics are mostly dominated by the relative density, ionic polarizability, relative covalence, and bond energy of M–O bond, respectively. A high Q × f value (61 800 GHz at 16.3 GHz) was obtained in BaCa2Ge3O9 ceramic due to its high rc (Ge–O) and low intrinsic dielectric loss. The BaCa2Si3O9 ceramic exhibited small |τf| value (‒36.4 ppm/°C) due to its large ESi‐O. Excellent microwave dielectric properties (εr = 8.31, Q × f = 61 800 GHz, and τf = ‒58.7 ppm/°C) were obtained for the BaCa2Ge3O9 ceramic. [ABSTRACT FROM AUTHOR]

The dielectric properties of a Ga‐based melilite type ceramic Sr2Ga2SiO7 via theoretical prediction based on far‐infrared spectroscopy and experimental measurement by the Hakki–Coleman method were studied in this work. Dense and single‐phase ceramics were fabricated via solid‐state reaction at 1330°C and exhibited comprehensive microwave dielectric properties (εr ∼ 7.6, Q × f ∼ 23 600 GHz, and τf ∼ −35.2 ppm/°C) at 14.3 GHz. Chemical modifications were proposed to adjust the thermal stability and reduce the densification temperature. By adding 10 mol% CaTiO3, the negative τf can be compensated to a near‐zero value of −3.8 ppm/°C. The densification temperature was reduced to 940°C by adding 3 wt.% LiF. A patch antenna was designed using Sr2Ga2SiO7 ceramic with a high radiation efficiency of 99.1% and a gain of 2.788 dBi at the center frequency of 4.371 GHz. All results indicate that the Sr2Ga2SiO7 ceramic has promising application potential for 5G wireless communication technology. [ABSTRACT FROM AUTHOR]

A novel high-efficiency dielectric patch antenna was fabricated using Sr 3- x Ca x V 2 O 8 ceramics. A typically temperature-stable Sr 3- x Ca x V 2 O 8 was achieved by tailoring the Ca2+ substitution to 30 mol% (x = 0.3), where well-balanced microwave dielectric properties were obtained (a near-zero value of +5.2 ppm/°C, a low ε r ∼ 13.4, and a moderate Q × f ∼ 18,500 GHz). To manifest the application potentiality in wireless communication, a patch antenna was fabricated from the x = 0.3 ceramic based on the simulated result using the CST Microwave Studio software, and it showed a high simulated radiation efficiency (99.7%) and a gain (5.35 dBi) at 3.421 GHz. All results indicate that the Sr 3- x Ca x V 2 O 8 ceramics have promising application potential for 5 G technology due to their prominent microwave dielectric properties, lightweight, and low cost. [ABSTRACT FROM AUTHOR]

In this paper, we focus on a space–time fractional diffusion equation with the generalized Caputo's fractional derivative operator and a general space nonlocal operator (with the fractional Laplace operator as a special case). A weak Harnack's inequality has been established by using a special test function and some properties of the space nonlocal operator. Based on the weak Harnack's inequality, a strong maximum principle has been obtained which is an important characterization of fractional parabolic equations. With these tools, we establish a uniqueness result of an inverse source problem on the determination of the temporal component of the inhomogeneous term, which seems to be the first theoretical result of the inverse problem for such a general fractional diffusion model. [ABSTRACT FROM AUTHOR]

A new topology of the power dividers is proposed, which has both good isolation performance and tunable wideband filtering. Based on the Wilkinson structure, on the one hand, to achieve good performance wideband port-to-port isolation, the two output ports are first connected in parallel through a resistor, and then through a quarter-wavelength parallel coupled line and transmission line. On the other hand, in order to realize the tunable wideband filtering response, a reconfigurable wideband filtering branch is formed, including stepped impedance open-circuit stubs, parallel coupled lines, and t-type tunable reflectors. The power divider prototype is theoretically calculated and verified by the odd-even mode method. The measurement results show that the tunable wideband filtering power divider centered at 3 GHz with a 66.7% fractional bandwidth, output port isolation maximum 15.8 dB, a return loss greater than 15 dB, while achieving wideband tunable in the range of about 0.6 GHz. [ABSTRACT FROM AUTHOR]

High-speed signal propagation systems require dielectric ceramics with low relative permittivity (ε r) and a high-quality factor (Qxf). In this paper, a novel low-permittivity borate ceramic (LiBO 2) was synthesized using a conventional solid-state reaction method. Based on the X-ray diffraction and Rietveld refinement, the LiBO 2 crystallized into a monoclinic structure with a space group of P21/c. Dense and single-phase ceramic was obtained at 640 °C with comprehensive microwave dielectric properties: a low relative permittivity (ε r) of 5.3, a moderate quality factor (Q × f) of 18,200 GHz at 16.3 GHz, and a temperature coefficient of resonant frequency (τ f) of − 66.2 ppm/°C. Good chemical compatibility with Ag electrode and thermal expansion coefficient of 25.4 ppm/°C was achieved demonstrating the potential applications as dielectric resonances in wireless communications and substrates in low-temperature cofired ceramics. [ABSTRACT FROM AUTHOR]

The three-dimensional reconstruction of porous media is of great significance to the research of mechanisms of fluid flow. The real three-dimensional structural data of porous media are helpful to describe the irregular topologic structures in porous media. The reconstruction of porous media will be inaccurate while only hard data or no conditional data are available. Reconstructed results can be more accurate, using soft data during reconstruction. Integrating soft data with hard data, a method based on multiple-point geostatistics (MPS) is proposed to reconstruct three-dimensional structures of porous media. The variogram curves and permeability, computed by lattice Boltzmann method (LBM), of the reconstructed images and the target image obtained from real volume data were compared, showing that the structural characteristics of reconstructed porous media using both soft data and hard data as conditional data are most similar to those of real volume data. [ABSTRACT FROM AUTHOR]

The elderly usually suffer from many diseases. Improving the quality of life of the elderly is an urgent social issue. In this present study, D-galactose treated aging mice models were used to reveal the effects of different animal sources and different doses of whey protein (WP) on the immune indexes organs and intestinal flora. A total of 9 groups were set up, including normal control (NC), negative control (NS), positive control (Vc), low-, medium- and high-doses of cow WP intervention groups (CL, CM and CH for short, correspondingly) and low-, medium- and high-doses of goat WP intervention groups (GL, GM and GH for short, correspondingly). The body weight gain, thymus/body weight ratio, superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, spleen immunoglobulins G (IgG), spleen interleukin-2 (IL-2) and spleen interleukin-2 (IL-6) were measured. Then, the intestinal contents were collected, and 16s genes of intestinal bacteria were sequenced to reveal the changes in bacterial flora structure. WP intervention significantly increased the weight gain, thymus/body ratio and SOD activity, but decrease the content of MDA. WP intervention increased some immune indicators. All the WP treated aging mice showed similar values of physiological indexes to that of the Vc group, even better. The relative abundance of Lactobacillus and Stenotrophomonas was increased and decreased, respectively, by both cow and goat WP. Lactobacillus may be involved in regulating the functional repair of organisms. In contrast, Stenotrophomonas might play a negative role in the immune and antioxidant capacity of the body. Combining physiological indicators and intestinal flora structure, low-concentration WP for cow and goat might be optimal for aging models. [ABSTRACT FROM AUTHOR]

Cerebral ischemia–reperfusion (I/R) injury is the common symptom of ischemic stroke, which poses a heavy burden to human health. Long non-coding RNA (lncRNA) is indicated to be a critical regulator in cerebral ischemia. This study aims to reveal the effects of lncRNA small nucleolar RNA host gene 15 (SNHG15) on oxygen–glucose deprivation and reoxygenation (OGD/R)-induced neuron injury and underlying mechanism. The expression levels of SNHG15, microRNA-455-3p (miR-455-3p) and tumour protein p53 inducible nuclear protein 1 (TP53INP1) mRNA were determined by quantitative real time polymerase chain reaction in P12 cells. The protein levels of TP53INP1, cleaved caspase-3, caspase-3, B-cell lymphoma-2 and BCL2-associated x protein (Bax) were detected by western blot in P12 cells. Cell viability and apoptosis were revealed by cell counting kit-8 assay and flow cytometry analysis, respectively, in P12 cells. Caspase-3 activity, the levels of tumor necrosis factor-α and interleukin-1β and the production of reactive oxygen species (ROS) were severally determined by caspase-3 activity assay, Enzyme-linked immunosorbent assay and ROS detection assay in P12 cells. The binding relationship between miR-455-3p and SNHG15 or TP53INP1 was predicted by starbase online database, and identified by dual-luciferase reporter, RNA pull-down or RNA immunoprecipitation assay. SNHG15 expression and the mRNA and protein levels of TP53INP1 were dramatically upregulated, while miR-455-3p expression was apparently downregulated in OGD/R-induced PC12 cells. SNHG15 silencing hindered the effects of OGD/R treatment on cell viability, apoptosis, inflammation and oxidative in PC12 cells; however, these impacts were restored after miR-455-3p inhibitor transfection. Additionally, SNHG15 acted as a sponge of miR-455-3p and miR-455-3p bound to TP53INP1. SNHG15 contributed to OGD/R-induced neuron injury by regulating miR-455-3p/TP53INP1 axis, which provided a novel insight to study lncRNA-directed therapy in ischemia stoke. [ABSTRACT FROM AUTHOR]

Although the clinical manifestation of COVID-19 is mainly respiratory symptoms, approximately 20% of patients suffer from cardiac complications. COVID-19 patients with cardiovascular disease have higher severity of myocardial injury and poor outcomes. The underlying mechanism of myocardial injury caused by SARS-CoV-2 infection remains unclear. Using a non-transgenic mouse model infected with Beta variant (B.1.351), we found that the viral RNA could be detected in lungs and hearts of infected mice. Pathological analysis showed thinner ventricular wall, disorganized and ruptured myocardial fiber, mild inflammatory infiltration, and mild epicardia or interstitial fibrosis in hearts of infected mice. We also found that SARS-CoV-2 could infect cardiomyocytes and produce infectious progeny viruses in human pluripotent stem cell-derived cardiomyocyte-like cells (hPSC-CMs). SARS-CoV-2 infection caused apoptosis, reduction of mitochondrial integrity and quantity, and cessation of beating in hPSC-CMs. In order to dissect the mechanism of myocardial injury caused by SARS-CoV-2 infection, we employed transcriptome sequencing of hPSC-CMs at different time points after viral infection. Transcriptome analysis showed robust induction of inflammatory cytokines and chemokines, up-regulation of MHC class I molecules, activation of apoptosis signaling and cell cycle arresting. These may cause aggravate inflammation, immune cell infiltration, and cell death. Furthermore, we found that Captopril (hypotensive drugs targeting ACE) treatment could alleviate SARS-CoV-2 induced inflammatory response and apoptosis in cardiomyocytes via inactivating TNF signaling pathways, suggesting Captopril may be beneficial for reducing COVID-19 associated cardiomyopathy. These findings preliminarily explain the molecular mechanism of pathological cardiac injury caused by SARS-CoV-2 infection, providing new perspectives for the discovery of antiviral therapeutics. [Display omitted] • SARS-CoV-2 Beta strain infection causes heart injury in wild-type mice. • SARS-CoV-2 infection causes beating cessation and cell cycle arresting in hPSC-CMs. • SARS-CoV-2 infection induces apoptosis and inflammatory cytokines release. • Captopril alleviates SARS-CoV-2 infection induced inflammation and apoptosis. [ABSTRACT FROM AUTHOR]

Acquiring the structures of porous media is very important when predicting flow properties in porous media. However, direct measurements of 3D microstructures of porous media with the resolution of microns or even nanometers are difficult to achieve due to the expensive cost of high-precision equipment. Therefore, as a typical stochastic simulation method, multiple-point statistics (MPS) was used to perform reconstruction based on real 3D volume data of porous media scanned by micro-CT. Because the ensemble of patterns extracted from a training image (TI) cannot be embedded into a linear space, the traditional MPS methods using linear dimensionality reduction, including filter-based simulation and distance-based pattern simulation, are not suitable to deal with the nonlinear situation. A new MPS method using isometric mapping, which is a method of nonlinear dimensionality reduction, to achieve nonlinear dimensionality reduction is proposed to decrease redundant data of TIs so that the subsequent simulation can be faster and more accurate for the reconstruction of porous media. Entropy theory is introduced to select a proper size of data template to balance the CPU cost and reconstructed quality. The comparisons between the reconstructed images and the target image show that the structural characteristics of reconstructed porous media using our method are similar to those of real volume data. This method also has shown advantages in reconstruction quality over typical methods using linear dimensionality reduction. [ABSTRACT FROM AUTHOR]

Most data in the real world are normally nonlinear or difficult to determine whether they are linear or not beforehand. Some linear dimensionality reduction algorithms, e.g., principal component analysis (PCA) and multi-dimensional scaling (MDS) are only suitable for linear dimensionality reduction of spatial data. The patterns extracted from training images (TIs) used in MPS simulation mostly are probably nonlinear, so for some MPS simulation methods based on dimensionality reduction, e.g., FILTERSIM using some filters created via the idea of PCA and DisPAT using MDS as a tool of dimensionality reduction, those linear methods for dimensionality reduction are not appropriate when realizing the dimensionality reduction of nonlinear data of patterns. Therefore, isometric mapping (ISOMAP) working as a nonlinear dimensionality reduction method used in manifold learning is introduced to map those patterns, regardless of being linear or nonlinear, into low-dimensional space. However, because the original ISOMAP has some disadvantages in computing speed and accuracy, landmark points of patterns are selected to improve the speed and neighborhoods of patterns are set to guarantee the quality of dimensionality reduction. Next, the sequential simulation similar to FILTERSIM is performed after low-dimensional data of patterns are classified by a density-based clustering algorithm. The comparisons with FILTERSIM and DisPAT show the improvement of pattern reproductivity and computing speed of our method for both continuous and categorical variables. [ABSTRACT FROM AUTHOR]

Ischemia reperfusion (I/R) injury is a key contributing factor to the pathogenic mechanism involved in cerebral infarction. Transmembrane protein 126b (TMEM126B), a mitochondrial complex I assembly factor, has been reported to have an intimate association with disease progression, but is little known in ischemia stroke. The present study was designed to explore the effects of TEME126B on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced neuronal PC12 cells. The mRNA level of TMEM126B was determined using qRT-PCR. The levels of ROS, MDA, and SOD, as well as inflammatory cytokines, were measured using corresponding commercial kits. Cell apoptosis rate was assayed by flow cytometry analysis, and the apoptosis-related proteins were measured using western blotting. ATP production measured by colorimetric reaction and mitochondrial membrane potential measured by JC-1 staining were conducted to determine mitochondrial dysfunction. The results showed that TMEM126B was upregulated upon I/R injury in vitro and in clinical, and was positively corrected with the degree of oxidative stress. TMEM126B knockdown significantly reduced oxidative stress and inflammation in OGD/R-induced PC12 cells. TMEM126B knockdown also attenuated cell apoptosis rate, accompanied with increased expressions of Bcl-2, XIAP and cleaved PARP-1, and decreased expressions of Bax, cleaved caspase 3 and cleaved caspase 9. Furthermore, TMEM126B knockdown exhibited cytoprotective roles through alleviating mitochondrial dysfunction, as assessed by ATP production and mitochondrial membrane potential. Collectively, this study indicates that TMEM126B knockdown protects against OGD/R-induced neuronal injuries through relieving oxidative stress, inflammation, apoptosis and mitochondria dysfunction, which provides a promising target for ischemic stroke treatment. [ABSTRACT FROM AUTHOR]