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Abstract Background Understanding the tooth anatomy is crucial for ensuring effective endodontic treatment. This study investigated the root canal morphology of the second mesiobuccal (MB2) canal in maxillary first molars (MFMs) in a Chinese population using cone-beam computed tomography (CBCT). Methods This study evaluated 486 MFMs with MB2 canals from 285 participants undergoing CBCT examination and determined the Vertucci’s classification and position of the MB2 canal orifice. The prevalence of the MB2 canal was correlated with the sex, age, and tooth side. The correlations between the prevalence of the MB2 canal and sex and tooth side were assessed using the Fisher's exact test. The chi-square test was used for evaluating the correlation between the prevalence of the MB2 canal and age. Results The number of type II, III, IV, V, VI, VII, and other root canals in the MFMs was 30.9%, 0.6%, 65.0%, 1.2%, 1.2%, 0.4%, and 0.6%, respectively. Among the 201 cases with bilateral inclusion, 87.6% showed consistent canal configuration. Results of the first clear apparent position (FCAP) of the MB2 canals showed that 434, 44, and 3 teeth had FCAP at the upper, middle, and bottom one-third of the root, respectively. The FCAPs of the MB2 canal in the MFMs with types II, IV, and VI, as well as types III and V canals showed significant differences (p

Urbanization is a significant indicator of city progress, and as urbanization advances, carbon emissions exhibit an increasing trend that must not be disregarded. Therefore, it is imperative to thoroughly examine the spatial and temporal variations as well as the factors influencing carbon emissions during the urbanization process. In this paper, based on the 2009–2019 PRD region, carbon emissions are measured from energy consumption, industrial production process, solid waste, and wastewater according to the IPCC coefficients, and spatial and spatial differences in carbon emissions are combined with spatial analysis and the drivers analyzed using the gray correlation scale. The results show that: (1) The total carbon emissions in the PRD region have been increasing over the study period, and the distribution of total carbon emissions shows a pattern of “strong in the east and weak in the west”, with energy consumption accounting for the highest proportion of carbon emissions. (2) The global Moran Index of carbon emissions in the PRD has been decreasing, with low and low clustering concentrated in Shaoguan and Zhaoqing, high and high clustering concentrated in Dongguan and Shenzhen, and low and high clustering concentrated in Shenzhen and Guangzhou, with cold spots mainly concentrated in Zhaoqing and hot spots mainly distributed in Guangzhou, Shenzhen, and Dongguan. (3) The degree of economic growth has a substantial influence on carbon emissions in the PRD cities, and the influence of technical advancement has intensified. Guangzhou City is propelled by low-carbon regulations that have a more equitable influence on all elements. Zhuhai City has a more significant influence on energy intensity, while Foshan City has a more noticeable decrease in the effect of foreign investment. To address the issue of carbon emissions, the government should establish appropriate rules to regulate carbon emissions in areas with high emissions, foster collaborative efforts across cities, and encourage the growth of environmentally friendly enterprises.

With the continuous advancement of urbanization and industrialization, non-grain production on cropland (NGPCL) is gradually becoming more widespread. This phenomenon will compress the space for grain production and trigger a global food crisis. How to scientifically understand and effectively control NGPCL has become a scientific issue. This study, conducted at the plot scale, establishes a measurement index for NGPCL and further explores the characteristics and driving mechanisms of NGPCL in mountainous areas. The results indicate the following: (1) Compared to plots for food-growing, plots for non-grain production tend to be more dispersed, with terraces showing the most significant dispersion, while plains exhibit the highest degree of aggregation. (2) In terms of irrigation conditions, irrigated land and dry land are more likely to undergo NGPCL. In terms of topography, slope croplands have the highest probability of being used for NGPCL. (3) Regions with steeper slopes, higher elevations, greater differences in altitude from the settlement, farther distances from settlements and roads, yet closer proximity to forests, are more likely to engage in NGPCL. (4) Different plot characteristics have varying impacts on NGPCL. Plot characteristics primarily affect the costs and returns of grain production, driving farmers to change their production patterns and triggering NGPCL.

Abstract Objective To investigate the clinical observation of autologous platelet-rich fibrin (PRF) assisting the revascularization of mature permanent teeth. Methods Twenty patients with mature permanent teeth were divided into experimental group and control group. The control group was treated with classic revascularization, and the experimental group was treated with PRF-assisted mature permanent tooth revascularization. Results After treatment, the total effective rate of the experimental group (100.00%) was higher than that of the control group (50.00%); the thickness of the root canal wall of the experimental group was higher than that of the control group, and the crown root length was lower than that of the control group; The bite degree, chewing function, color, overall aesthetic score, and satisfaction rate of the patients were higher, and the difference was statistically significant (P

As a candidate anode material for Li-ion batteries, Bi-based materials have attracted extensive attention from researchers due to their high specific capacity, environmental friendliness, and simple synthesis methods. However, Bi-based anode materials are prone to causing large volume changes during charging and discharging processes, and the effect of these changes on lithium storage performance is still unclear. This work introduces that Bi/C nanocomposites are prepared by the Bi-based MOF precursor calcination method, and that the Bi/C nanocomposite maintains a high specific capacity (931.6 mAh g−1) with good multiplicative performance after 100 cycles at a current density of 100 mA g−1. The structural evolution of Bi/C anode material during the first cycle of charging and discharging is investigated using in situ synchrotron radiation SAXS. The SAXS results indicate that the multistage scatterers of Bi/C composite, used as an anode material during the first lithiation, can be classified into mesopores, interspaces, and Bi nanoparticles. The different nanostructure evolutions of three types of Bi nanoparticles were observed. It is believed that this result will help to further understand the complex reaction mechanism of Bi-based anode materials in Li-ion batteries.

Abstract Background The objective of this report was to highlight the importance of using a dental operating microscope (DOM) to locate supernumerary canals and diagnose variations in root canals using cone-beam computed tomographic (CBCT) images. Case presentation A 35-year-old Chinese female had repeated swelling in the upper right posterior maxilla for 3 months and was referred to evaluate symptomatic apical periodontitis and mesotaurodonts for upper right first permanent molar and upper right second permanent molar. Root canal therapy was proposed and conducted with the use of DOM and CBCT. Conclusions Proper diagnosis and careful clinicoradiological examination are necessary, and it is essential to reinforce the knowledge of the rare morphology of root canals for clinicians.

The basic density (ρ), kinematic viscosity (v) and surface tension (γ) data of the 1,2-propanediol (1,2-PPD) (1) + 1,2-propane diamine (1,2-PDA) (2) binary system at T = (293.15, 298.15, 303.15, 308.15, 313.15 and 318.15) K were reported under atmospheric pressure (889 hectopascals in Hohhot, China). After that, the absolute viscosity (η), excess volume (VmE), viscosity deviation (Δη), surface tension difference (Δ γ), apparent molar volume (Vφ,1 and Vφ,2), partial molar volume (V1¯ and V2¯), isothermal expansion coefficient (αp) and excess Gibbs free energy (ΔG*E) of the binary system were further calculated. Meanwhile, the Redlich-Kister (R-K) equations were fitted to VmE, Δ η, and Δ γ values, and the corresponding equation coefficients were obtained to estimate the errors between the experimental and calculated values. Finally, the binary system was characterized by FTIR, UV-vis, FLS, 1H NMR, Raman spectroscopic techniques, and the bond energy and bond length between molecules were calculated by Gaussian 09 software to discuss the intermolecular interaction between 1,2-PPD and 1,2-PDA. The results show that hydrogen bonding interaction does exist among molecules in the form of -OH···N-. Herein, the work provides a basis for engineering design and also provides fundamental data for the application of the binary system.

Lung cancer is a highly prevalent type of cancer, accounting for 11.6% of all cancer incidences. Early detection and treatment can significantly improve the survival rate and quality of life of patients; however, there is no accurate, effective, and easy-to-use test for early lung cancer screening. In this study, flow cytometry was used to detect the presence of CD45+EpCAM+ cells in tumor tissues and peripheral blood mononuclear cells (PBMCs) in patients with lung cancer. Moreover, the proportion of CD45+EpCAM+ cells in PBMCs of patients with lung cancer was found to be significantly higher than that of healthy volunteers. Tumor-related serum markers level was also measured in the peripheral blood of these patients using an electrochemiluminescence assay. The correlation between CD45+EpCAM+ cells, carcinoembryonic antigen (CEA), and lung cancer was investigated using receiver operating characteristic (ROC) curve analysis, which showed the sensitivity and specificity of the CD45+EpCAM+ cell to be 81.58% and 88.89%, respectively. Further analysis yielded an area under the ROC curve (ROC/area under the curve [AUC]) of 0.845 in patients PBMCs with lung cancer, which was slightly higher than that of CEA (0.732). Therefore, the detection of CD45+EpCAM+ cells in PBMCs may be helpful for the early screening and auxiliary diagnosis of lung cancer.

The electrochemical CO2 reduction reaction (CO2RR) is a promising approach for mitigating the greenhouse effect arising from anthropogenic CO2 emission. Nonetheless, poor product selectivity associated with electrochemical catalysts is the main technical problem for the application of CO2RR technology. The catalytic performance of nano-catalysts is strongly dependent on their microstructural features. Anomalous small-angle X-ray scattering (ASAXS) is one of the most effective techniques for studying nanostructural change in an operando way, especially for complex systems and mixed-element catalyst situations. Furthermore, based on the research results of ASAXS, appropriate catalyst components and nanostructures can be designed to achieve stable catalytic performance of the catalyst, promote catalytic reaction rate, or improve catalytic reaction selectivity. In this paper, the basic concept, principle, and applications in different systems of ASAXS are reviewed thoroughly. Finally, the development prospect of ASAXS in the field of electrocatalysis is prospected. It is hoped that this review will further promote ASAXS technology to play a more far-reaching impact in the field of electrocatalytic CO2RR.

Lung cancer has the highest mortality rate among human cancers, and the majority of deaths result from metastatic spread. The tumor microenvironment plays an important role in suppressing the immune surveillance and elimination of tumor cells. A few studies have reported the presence of CD45+EpCAM+ double-positive cells in cancer, but the underlying mechanism remains unclear with respect to how these cells originate and their function in cancer biology. In this study, we analyzed 25 lung tumor samples. We confirmed the presence of CD45+EpCAM+ cells in lung cancer, and these cells exhibited higher apoptosis than CD45+EpCAM− cells. Using co-culture of lung cancer cell-derived exosomes with healthy donor peripheral blood mononuclear cells, we recapitulated CD45+EpCAM+ cell formation and increased apoptosis that occurs in patients with primary lung cancer. Further analysis suggested that microRNAs in lung cancer cell-derived exosomes may alter the gene expression profile of CD45+EpCAM+ cells, resulting in elevated TP53 expression and increased apoptosis. To our knowledge, this is the first report of cancer cell-derived exosomes that can inhibit the immune system by promoting immune cell apoptosis.

In order to reconstruct the sparse check matrix of LDPC, a new algorithm which could directly reconstruct the LDPC was proposed.Firstly, according to the principle of the traditional reconstruction algorithm, the defects of the traditional algorithm and the reasons for the defects were analyzed in detail.Secondly, based on the characteristics of sparse matrix, some bit sequences in code words were randomly extracted for Gaussian elimination.At the same time, in order to reliably realize that the extracted bits sequence could contain parity check nodes, the multiple random variables were determined based on the probability of containing check nodes in one extraction.Finally, the statistical characteristics of LDPC under the suspected check vector was analyzed.Based on the minimum error decision rule, the sparse check vector was determined.The simulation results show that the rate of reconstruction of most LDPC in IEEE 802.11 protocol can reach more than 95% at BER of 0.001, and the noise robustness of the proposed method is better than that of the traditional algorithm.At the same time, the new algorithm not only does not need sparseness of parity check matrix, but also has the good performance for both diagonal and non-diagonal check matrix.

In order to solve the problem of the blind recognition of polar codes, the theorem 1 and theorem 2 were proved firstly, which reflects the relationship between length and rate of actual polar codes, and then theorem 3 which could distinguish frozen bit and information bit positions was also proved.Based on these three theorems, the codewords matrixes and Kronecker matrixes were constructed by traversing the possible code length values.Then the information bits were traversed to detect the check relationship between the codewords and the suspected dual space.In order to detect the check relationship, log likelihood ratio was introduced, based on its characteristics and optimal criteria, the code rate and information bit positions were estimated.The simulation results show that the conclusions of the three theorems are consistent with the results.At the same time, the proposed algorithm has a strong error tolerance.Under 6.5 dB and code length of 1024, the rate of recognition can reach more than 98%.

In order to overcome the poor performance of existing algorithms for recognition of BCH code in low signal-to-noise ratio (SNR),a recognition algorithm based on average cosine conformity was proposed.Firstly,by traversing the possible values of code length and m-level primitive polynomial fields,the code length was identified by matching the initial code roots.Secondly,on the premise of recognizing the code length,the GF(2m) domain was traversed under the m-level primitive polynomial and the primitive polynomial with the strongest error-correcting ability was the generator polynomial for the domain.Finally,the minimum common multiple corresponding to the minimum polynomial of code roots was obtained,and the BCH code generator polynomial was recognized.In checking matching,the statistic of average cosine conformity was introduced.The optimal threshold was solved based on the minimum error decision criterion and distribution of the statistic to realize the fast identification of the BCH.The simulation results show that the deduced statistical characteristics are consistent with the actual situation,and the proposed algorithm can achieve reliable recognition under SNR of 5 dB and code length of 511.Comparing with existing algorithms,the performance of the proposed algorithm is better than that of the existing soft-decision algorithm and 1~3.5 dB better than that of the hard-decision algorithms.

Interferon (IFN) system is considered as the first defense line against viral infection, and it has been extensively studied in vertebrates from fish to mammals. In invertebrates, Vagos from arthropod and IFN-like protein (CgIFNLP) from Crassostrea gigas appeared to function as IFN-like antiviral cytokines. In the present study, the CgIFNLP protein in hemocytes was observed to increase after Poly (I:C) stimulation. After CgIFNLP was knocked down by RNAi, the mRNA expression of IFN-stimulated genes (CgISGs) was significantly inhibited. Both cyclic GMP-AMP synthase (CgcGAS) and stimulator of interferon gene (CgSTING) identified from oyster were able to recognize the double-stranded nucleic acid [Poly (I:C) and dsDNA] and expressed at high level after Poly (I:C) stimulation. The expression of CgIFNLP and interferon regulatory factors (CgIRF1/8) and the nuclear translocation of CgIRF8 were all suppressed in CgcGAS-RNAi or CgSTING-RNAi oysters after Poly (I:C) stimulation. The expression level of CgSTING and TANK binding kinase1 (CgTBK1) did not decrease in CgcGAS-RNAi oysters. After CgSTING was knocked down, the high expression of CgTBK1 induced by Poly (I:C) was prevented significantly. These results indicated that there was a primitive IFN-like antiviral mechanism dependent on the cGAS/STING–TBK1–IRFs regulatory axis in mollusks, which was different from the classic cGAS–STING–TBK1 signal pathway in mammals.

Abstract Let f be a transcendental meromorphic function of finite order and c be a nonzero complex number. Define Δcf=f(z+c)−f(z) $\Delta _{c}f=f(z+c)-f(z)$. The authors investigate the existence on the fixed points of Δcf $\Delta _{c}f$. The results obtained in this paper may be viewed as discrete analogues on the existing theorem on the fixed points of f′ $f'$. The existing theorem on the fixed points of Δcf $\Delta _{c}f$ generalizes the relevant results obtained by (Chen in Ann. Pol. Math. 109(2):153–163, 2013; Zhang and Chen in Acta Math. Sin. New Ser. 32(10):1189–1202, 2016; Cui and Yang in Acta Math. Sci. 33B(3):773–780, 2013) et al.

A new algorithm based on logarithmic conformity was proposed.Firstly,based on the probability of total RSC coding equation,the concept of logarithmic coincidence degree,which could measure the establishment of coding equation,was introduced.Then because of constraint length of RSC,the polynomial database could be generated,and then logarithmic conformity of every polynomial could be calculated when traversing the database.As the results,the RSC could be recognized,because the correct polynomial could make the conformity maximum.The algorithm has small amount of calculation because of finite traversal,which was only related to amount of intercepted data,besides,this algorithm has good error tolerance by soft decisions.The simulation results show that the correct ratio of recognition can reach 90% at SNR of 0 dB and its performances are obviously superior to those of existing algorithms.

The present study aims to reveal the mechanism by which miR-430s regulate steroidogenesis in larval rice field eel Monopterus albus. To this end, M. albus embryos were respectively microinjected with miRNA-overexpressing mimics (agomir430a, agomir430b, and agomir430c) or miRNA-knockdown inhibitors (antagomir430a, antagomir430b, and antagomir430c). Transcriptome profiling of the larvae indicated that a total of more than 149 differentially expressed genes (DEGs) were identified among the eight treatments. Specifically, DEGs related to steroidogenesis, the GnRH signaling pathway, the erbB signaling pathway, the Wnt signaling pathway, and other pathways were characterized in the transcriptome. We found that steroidogenesis-related genes (hydroxysteroid 17-beta dehydrogenase 3 (17β-hsdb3), hydroxysteroid 17-beta dehydrogenase 7 (17β-hsdb7), hydroxysteroid 17-beta dehydrogenase 12 (17β-hsdb12), and cytochrome P450 family 19 subfamily a (cyp19a1b)) were significantly downregulated in miR-430 knockdown groups. The differential expressions of miR-430 in three gonads indicated different roles of three miR-430 (a, b, and c) isoforms in regulating steroidogenesis and sex differentiation. Mutation of the miR-430 sites reversed the downregulation of cytochrome P450 family 17 (cyp17), cyp19a1b, and forkhead box L2 (foxl2) reporter activities by miR-430, indicating that miR-430 directly interacted with cyp17, cyp19a1b, and foxl2 genes to inhibit their expressions. Combining these findings, we concluded that miR-430 regulated the steroidogenesis and the biosynthesis of steroid hormones by targeting cyp19a1b in larval M. albus. Our results provide a novel insight into steroidogenesis at the early stage of fish at the molecular level.

Homogeneous CaCO3 microspheres were controllably synthesized via a simple hydrothermal method without using extraneous additives by Ca(OH)2 saturated solution reacted with CO2 storage material (CO2SM), which was obtained by absorbing CO2 gas in a system containing equimolar ethylenediamine (EDA) and polyethylene glycol 400 (PEG). Specifically, homogeneous pure vaterite spheres were obtained by using 160 g/L CO2SM solution at 100 °C and a reaction time of two hours. It is noteworthy that the EDA and PEG, which are released from CO2SM, have dual functions as a CO2 absorber and crystal regulator in the process of controlling the crystallization of CaCO3 crystals.

The purpose of this paper is to investigate the fixed points of meromorphic functions in annuli. Some well-known facts of fixed points for meromorphic functions in the plane will be considered in annuli.

The main purpose of this paper is to establish the Milloux inequality of E-valued meromorphic function from the complex plane ℂ to an infinite dimensional complex Banach space E with a Schauder basis. As an application, we study the Borel exceptional values of an E-valued meromorphic function and those of its derivatives; results are obtained to extend some related results for meromorphic scalar-valued function of Singh, Gopalakrishna, and Bhoosnurmath.

Let f be a transcendental meromorphic function of order less than one. The authors prove that the exact difference Δf=fz+1-fz has infinitely many fixed points, if a∈ℂ and ∞ are Borel exceptional values (or Nevanlinna deficiency values) of f. These results extend the related results obtained by Chen and Shon.

By applying Ahlfors theory of covering surface, we establish a fundamental inequality of meromorphic function dealing with multiple values in an angular domain. As an application, we prove the existence of some new singular directions for a meromorphic function f, namely a Bloch direction and a pseudo-T direction for f.

In the title compound, C13H11N3Se, the dihedral angle between the mean plane of the fused selenoazolopyridine ring system and the p-toluidine ring is 14.260 (5)°. In the crystal, molecules are linked by N—H...N hydrogen bonds, forming zigzag chains extending along the b-axis direction.

The main purpose of this paper is to investigate the characteristic functions and Borel exceptional values of E-valued meromorphic functions from the ℂR={z:|z|