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The Large High Altitude Air Shower Observatory (LHAASO) Collaboration has observed ultrahigh-energy photons up to 1.4 PeV from 12 |$\gamma$| -ray Galactic sources. In particular, the γ-ray spectra of the sources J2226+6057, J1908+0621, and J1825−1326 have been published. We investigate the possibility of suggested origin pulsars near the sources as the PeVatrons. The pulsar is described by a rotating magnetic dipole. Assuming protons are uniformly distributed out of the light cylinders, we obtain the Lorentz distribution of proton energy spectrum. It is found that the protons around pulsar could be accelerated to PeV at short times. The hadronic γ-ray spectra of the suggested origin pulsars are in good agreement with the LHAASO observed γ-ray spectra of the sources J2226+6057, J1908+0621, and J1825−1326. [ABSTRACT FROM AUTHOR]

The poor operational stability of electrolytes is a persistent impediment in building redox flow battery technology; choosing suitable stability additives is usually the research direction to solve this problem. The effects of five phosphate containing additives (including 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), hexamethylene diamine tetramethylene phosphonic acid (HDTMPA), amino trimethylene phosphonic acid (ATMPA), sodium ethylenediamine tetramethylene phosphonate (EDTMPS), and diethyl triamine pentamethylene phosphonic acid (DTPMP)) on the thermal stability and electrochemical performance of the positive electrolyte of vanadium redox flow battery were investigated. With 0.5 wt% addition, most of the selected additives were able to improve the thermal stability of the electrolyte. HEDP and HDTMPA extended the stability time of the pentavalent vanadium electrolyte at 50 °C from 5 days (blank sample) to 30 days and 15 days, respectively. The electrochemical performance of the electrolyte was further investigated by cyclic voltammetry, steady state polarization, and electrochemical impedance spectroscopy tests. It was found that most of the additives enhanced the electrochemical activity of the positive electrolyte, and the diffusion coefficients, exchange current densities, and reaction rate constants of V(IV) species became larger with the addition of these additives. It is verified that the thermal stability and electrochemical stability of the electrolyte are significantly improved by the combination of ATMPA + HEDP or ATMPA + HDTMPA. This study provides a new approach to improve the stability of the positive electrolyte for vanadium redox flow battery. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study the effects of steam temperature, sludge thickness, and steam flow on the drying characteristics and drying kinetics of sludge superheated steam and optimize the process parameters of sludge superheated steam drying by using the response surface method and taking relative unit energy consumption as the response value. Single-factor test of superheated steam drying of sludge was conducted under different drying conditions of steam temperature (180, 195, 220, and 260°C), sludge thickness (2, 3.5, 6, and 10 mm), and steam flow rate (22, 29, 36, and 40 m3/h). Taking relative unit energy consumption as the response value and steam temperature, sludge mass (corresponding to sludge thickness), and steam flow as the test factors, the three-factor and five-level response surface test was conducted on the sludge. The experimental results show that steam temperature and sludge thickness had a significant influence on the drying characteristics of superheated sludge steam (p < 0.05). With the increase of steam temperature, the decrease of sludge thickness, and the increase of steam flow, the drying time of sludge will be shortened, the drying efficiency of sludge will be improved, and the maximum condensation amount and recovery time will be reduced. The quadratic polynomials, linear equation, and logarithmic model can better fit the change law of water variation of the sludge of superheated steam condensation section, recovery section, and drying section. With the increase of steam temperature, sludge thickness, and steam flow rate, the effective diffusion coefficient also increases. The activation energy of sludge superheated steam drying was 13.42 kJ/mol at a sludge thickness of 6 mm, steam flow rate of 22 m3/h, and different steam temperatures. The order of influence degree of three test factors on relative unit energy consumption is as follows: sludge mass (corresponding to sludge thickness) > steam flow rate > steam temperature. According to response surface test analysis, the optimal drying process with relative unit energy consumption is steam temperature of 215°C, sludge mass of 25 g (corresponding sludge thickness of 8 mm), and steam flow of 30 m3/h. Under this drying process parameter, the minimum energy consumption of sludge superheated steam drying is 284.61 kJ/g. Compared with the relative unit energy consumption value obtained in the verification test, the relative error is 1.65%. [ABSTRACT FROM AUTHOR]

The damping effect of the free-streaming neutrinos on the second order gravitational waves is investigated in detail. We solve the Boltzmann equation and give the anisotropic stress induced by neutrinos to second order. The first order tensor and its coupling with scalar perturbations induced gravitational waves are considered. We give the analytic equations of the damping kernel functions and finally obtain the energy density spectrum. The results show that the free-streaming neutrinos suppress the density spectrum significantly for low frequency gravitational waves and enlarge the logarithmic slope n in the infrared region ( k ≪ k ∗ ) of the spectrum. For the spectrum of k ∗ ∼ 10 - 7 Hz , the damping effect in the range of k < k ∗ is significant. The combined effect of the first and second order could reduce the amplitude by 30 % and make n jump from 1.54 to 1.63 at k ∼ 10 - 9 Hz , which may be probed by the pulsar timing arrays (PTA) in the future. [ABSTRACT FROM AUTHOR]

The naturally occurring quercetin flavonoid, dihydroquercetin, is widely distributed in plant tissues and has a variety of biological activities. Herein, a magnetic molecularly imprinted solid‐phase extraction was tailor made for selective determination of dihydroquercetin in Larix griffithiana using high‐performance liquid chromatography. Amino‐functionalized core‐shell magnetic nanoparticles were prepared and characterized using scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and infrared spectroscopy. The polymer had an average diameter of 250 ± 2.56 nm and exhibited good stability and adsorption for template molecule, which is enriched by hydrogen bonding interaction. Multiple factors for extraction, including loading, washing, elution solvents, and extraction time, were optimized. The limit of detection was 1.23 μg/g. The precision determined at various concentration of dihydroquercetin was less than 4% and the mean recovery was between 74.64 and 101.80%. It has therefore been shown that this protocol can be used as an alternative extraction to quantify dihydroquercetin in L. griffithiana and purify quercetin flavonoid from other complex matrices. [ABSTRACT FROM AUTHOR]

Abstract When face was inverted, dynamic gaze cues could still effectively direct attention despite the disruption of configural face processing, but the static gaze cues could not. The present study investigated the role of the motion cue in the dynamic Gaze-Cueing Effect (GCE). With schematic and real faces, we employed the gaze-cueing paradigm to examine the differences among three kinds of cues (static gaze cue, dynamic gaze cue and motion cue) based on behavioral results and event-related potentials. Behavioral results revealed significant GCE in all conditions. In the schematic face group, the motion cue (two symmetrical dots shifting slightly to the side) induced a significantly smaller GCE than the dynamic gaze cues (two symmetrical dots moving within a rounded circle), while in the real face group, the motion cue (that is, the inverted-face gaze cue) remained a strong GCE compared with other conditions. With regard to the ERP results, we found the early directing attention negativity (EDAN), which was sensitive to voluntary cues (e.g. arrow cue) rather than gaze cue, in the schematic motion cue condition, but not in the inverted-face gaze cue condition. We supposed that the motion cue (real face) could activate the configural face processing even when the face is inverted. This finding supported that EDAN reflected a cue-triggered attention shift. Highlights • The neural mechanism of dynamic gaze-cueing effect (GCE) was explored; • The analysis of P1 component revealed a significant smaller GCE for pure motion cue; • Dynamic inverted-face gaze cue remained strong GCE compared with upright gaze cue; • Motion cue rebooted configural process of inverted face according to lateralized ERPs; • Early directing attention negativity (EDAN) reflected a cue-triggered attention shift. [ABSTRACT FROM AUTHOR]

We study the second-order scalar and density perturbations generated by Gaussian curvature perturbations and primordial gravitational waves in the radiation-dominated era. After presenting all the possible second-order source terms, we obtain the explicit expressions of the kernel functions and the power spectra of the second-order scalar perturbations. We show that the primordial gravitational waves might affect second-order energy density perturbation δ (2) = δ ρ (2) / ρ (0) significantly. The effects of primordial gravitational waves are studied in terms of different kinds of primordial power spectra. [ABSTRACT FROM AUTHOR]

• The N235–MIBK system effectively separate niobium from H 2 SO 4 solution with oxalic acid addition. • The method avoids the introduction of HF or fluoride. • The method demonstrates excellent niobium selectivity over impurities in H 2 SO 4 solution. • The extraction and stripping multi-stage counter-current tests exhibit high efficiency. A fluoride-free solvent extraction method for niobium separation in leached sulfuric mother liquor of ilmenorutile was proposed in this paper. The extraction system comprising trioctyl tertiary amine (N235) and 4-methyl-2-pentanone (MIBK) demonstrated good extraction efficiency and selectivity of niobium over titanium and iron impurities in sulfuric acid–oxalate solutions. Details of extraction, scrubbing, and stripping processes were investigated herein, and its practical effectiveness in both batch and multi-stage simulated counter-current modes was verified. Over 73.8% niobium was extracted under optimum conditions, and only 2.8% titanium and 1.7% iron were co-extracted. The recovery of niobium reached 99.1% in the four-stage simulated counter-current extraction tests. In the three-stage simulated counter-current stripping tests, the stripping efficiency of niobium reached 99.7% with 2.0 mol/L HNO 3. Qualified niobium oxide products were prepared. The enthalpy change, entropy change, and the standard Gibbs free energy change (Δ Ho , Δ So , and Δ Go , respectively) corroborated the exothermicity, orderliness, and spontaneity of the reaction. The possible composition of the extraction complex was [NbO(C 2 O 4) 2 (H 2 O) 2 ]−, as supported by a Fourier transform infrared spectroscopy and ultraviolet–visible spectrophotometry. The extraction mechanism was inferred to be the outer-sphere complexation through physical binding which was the association of R 3 NH+ in N235 with the [NbO(C 2 O 4) 2 (H 2 O) 2 ]−. A preliminary mass balance indicated that 203.92 g Nb 2 O 5 was generated from 1000 g raw material ilmenorutile. [ABSTRACT FROM AUTHOR]

The sludge is known as the byproduct generated in the process of pollution control. It is featured by the high moisture content, complicated components and massive deadly microorganism, thus easily leading to secondary pollution. The dehydration is a necessary process to realize the sludge harmless reduce the sludge amount and improve the resource utilization. The thermal drying is a feasible method to reduce the moisture content. The process of hot air drying will cause a large amount of harmful exhaust gas, adding to the difficulty and cost of controlling exhaust gas. The sludge drying, which uses superheated steam as the drying medium, will further lower the risk of explosion and reduce the harmful gas account due to the absence of oxygen in the drying medium. However, the superheated steam drying of sludge is also faced with the problems such as energy consumption and long drying time. Hence, it has become a major task to dry the sludge in an economic and effective manner. The purpose of this research is to determine the technological parameters for optimal sludge superheated steam drying. Besides building the experimental device for superheated steam drying under atmospheric pressure and choosing the relative unit energy consumption and the average drying strength as the evaluation indices, this paper has also designed the experiment of three-factor quadratic orthogonal rotation combination. A mathematical model is also built, which adopts the technological parameters for sludge superheated steam drying including superheated steam temperature sludge quality and superheated steam flow. In addition, this paper has employed the single-factor and two-factor method to analyze the relationship between various factors and evaluation indices. According to the analysis on experimental data, the established regression equation of establishing is significant, and the coefficient of determination on the relative unit energy consumption and the average drying strength were 0.842 and 0.797, respectively. The 3 factors listed in the descending order of their importance to the 2 evaluation ind ices are sludge mass, steam flow and steam temperature. For the sludge superheated steam drying in terms of relative unit energy consumption, the optimal technological parameters are presented as follows, steam temperature being 215°C, superheated steam flow being 30 m³/h, sludge mass being 26 g (8 mm thickness approximately) and steam flow being 30 m³/h. Under these conditions, the predicted relative unit energy consumption is 281.313 kJ/g. The actual relative unit energy consumption gained from the validity experiment is 280 kJ/g, with the relative error being 0.467%. Hence, the experimental result can provide reference for parameter optimization of sludge superheated steam drying and the design of drying equipment. [ABSTRACT FROM AUTHOR]

The production of sewage sludge from wastewater treatment plants has been continuously increasing in China. One way to manage sewage sludge is drying, which yields a solid with low humidity. This solid can be easily stored, recycled and transported to other facilities. The drying of sewage sludge has been proved to considerably reduce solid volumes. Using superheated steam in the drying process can lead to substantial energy, if the vapour evaporating from the materials is used elsewhere in overall process. Therefore, superheated steam drying is an attractive drying process for industrial use especially if the cost energy for the drying is a major part of the cost of manufacture such as sewage sludge drying process. In order to further study the moisture diffusion mechanism and effective diffusivity of thin layer of sludge in superheated steam drying, this paper ignoring the influence of sample's moisture content change on effective diffusivity when determining the effective diffusivity through drying method, and adopts Fourier number method and optimization method respectively to calculate the effective diffusivity of sludge thin layers with the thickness of 2, 4, 6 and 10 mm at superheated steam temperature from 120° to 280°, respectively. Relations of the effective diffusivity with superheated steam temperature and the thickness of thin layer were analyzed. The results showed that the effective diffusivity values derived from Fourier number method and optimization method were basically identical, and the effective diffusivity values and change characteristics of thin layer sludge in superheated steam drying were more accurately reflected based on these two methods. Calculation results derived from the Fourier number method and optimization method showed that the effective diffusivity of sludge with the thickness at 4 mm were 2.52×10-10-2.93×10-9m2/s and 2.75×10-10-3.32×10-9 m2/s respectively at the temperature 120-280°,and the effective diffusivity of sludge with thicknesses of 2, 4, 6 and 8 mm were 3.85×10-10-2.28×10-9 m2/s and 4.40×10-10-2.72×10-9 m2/s respectively at the temperature of 160°. The effective diffusivity increased gradually with the increase of superheated steam temperature and the thickness of thin layer, and had a linear relationship with the two parameters. By using the multiple linear regression method, simplified expressions that reflect the relationship between effective diffusivity and drying temperature and thickness of layer were established respectively according to Fourier number method and optimization method, with the corresponding determination coefficient of 0.9982 and 0.9956. The calculation results can provide a valuable reference for the analysis of moisture diffusion process and effective diffusion coefficient of thin sludge layer in superheated steam drying. [ABSTRACT FROM AUTHOR]

The leach liquor of sodium-roasted vanadium slag in vanadium industry is an alkaline solution containing vanadium, sodium, chromium, and other impurities, and preparing high-purity vanadyl sulfate electrolyte (used in vanadium redox flow battery) directly from this solution is challenging but cost-effective. A novel process consisting of selective reduction–precipitation of chromium and solvent extraction of vanadium was proposed and optimized in this study. Approximately 90% of Cr(V I) in the solution was reduced to Cr(III) and precipitated after adding sodium sulfite at a pH of 5.77 and 25 °C, while V(V) remained in this process and needed a further reduction to V(IV) prior to extraction. More than 99.9% of V(IV) remained in the solution was extracted by two-stage extraction using the "P507 + TBP + kerosene" extractant system at a pH of 2.00 and an organic-to-aqueous phase ratio of 1.5:1. Sodium entrained in the organic phase was washed off through three-stage scrubbing. A high-purity vanadyl sulfate solution of 2.1 mol L−1 was prepared by two-stage stripping using 5.5 mol L−1 sulfuric acid. According to the slope analysis and infrared spectra, the extraction of V(IV) by P507 follow the cation exchange mechanism. This study provides a feasible way to remove chromium and recover vanadium in the form of vanadyl sulfate from the industrial leach liquor of sodium-roasted vanadium slag. • VOSO 4 solution was produced from leaching solution of sodium-roasted vanadium slag. • Chromium(VI) was removed by selective reduction–precipitation. • Vanadium was extracted by the "P507 + TBP + kerosene" extractant system. • Parameters of precipitation, extraction, scrubbing, and stripping were optimized. • Cation exchange mechanism was involved in the extraction of vanadium. [ABSTRACT FROM AUTHOR]

Generally, sludge exists with high moisture content. De-water is the first and crucial step in disposal processes such as land filling, composting, building materials, and incineration. Currently, there are many studies on sludge drying by different heat transfer modes such as conduction and convection. But in most studies, the sludge drying was carried out under an atmosphere of air, which had disadvantages in high-energy consumption and an abundant quantity of exhaust. Superheated steam drying has been used to dehydrate a variety of products, including meat, grain stillage, lignite, and wood, because of environmental protection, non-oxidation, and higher drying efficiency advantages. The purpose of this study was to investigate the drying characteristics of superheated-steam on a thin layer of sludge. Thin layer drying experiments of sludge samples with different thicknesses under a series of superheated steam temperatures were carried out. Sludge samples were collected in a local wastewater treatment plant after mechanical dewatering. The size of the sludge samples were taken over an area of 100 mm×100 mm, having thicknesses of 2, 4, 6, and 10 mm, respectively. The temperatures of superheated steam were controlled by the amount of the access heaters. The experiments of superheated steam drying were conducted at 160, 200, 240, and 280°C, respectively. Relations between the model parameters and temperature and thickness for the moisture ratio of sludge in relation to drying time were determined. The results showed that sludge samples were not oxidized or burnt after superheated steam drying even at high temperatures. The dense crack and rough surface of sludge during superheated steam drying were beneficial to the drying process. At the beginning of the drying process, the mass of the samples increased due to superheated steam coming in contact with the cold surface of the sludge as the initial temperature of the sludge is close to room temperature (around 20°C). As a result, the drying time of sludge samples to reach a certain moisture content increased. The increase in the mass of condensation water and drying time was greatly influenced by the temperature of superheated steam. As a result, the higher the temperature, the smaller the increase. However, the increase was hardly influenced by the thickness of sludge. The Effective moisture diffusivity was calculated by using Fick’s second law. Thin layers of sludge formed by superheated steam drying having thicknesses of 2, 4, 6, and 10 mm had effective diffusion coefficient variations of 2.0641×10-9-8.8527×10-9, 4.3738×10-9-1.6626×10-8, 6.6082×10-9-2.46×10-8, and 1.1916×10-8-4.0806×10-8 m2/s at the temperature 160-280°C. The linear relationship between the natural logarithm of the effective diffusion coefficient and reciprocal of temperature was built based on the Arrhenius empirical formula. The activation energy values of 2, 4, 6, and 10 mm thicknesses of sludge were 26.250, 22.032, 21.894, and 20.961 kJ/mol. A valuable reference for the parameter optimization and equipment design of sludge superheated steam drying was provided by the experimental results. [ABSTRACT FROM AUTHOR]

Preoperative observation of liver status in patients with liver tumors by abdominal Computed Tomography (CT) imaging is one of the essential references for formulating surgical plans. Preoperative vessel segmentation in the patient's liver region has become an increasingly important and challenging problem. Almost all existing methods first segment arterial and venous vessels on CT in the arterial and venous phases, respectively. Then, the two are directly registered to complete the reconstruction of the vascular system, ignoring the displacement and deformation of blood vessels caused by changes in body position and respiration in the two phases. We propose an unsupervised domain-adaptive two-stage vessel segmentation framework for simultaneous fine segmentation of arterial and venous vessels on venous phase CT. Specifically, we first achieve domain adaptation for arterial and venous phase CT using a modified cycle-consistent adversarial network. The newly added discriminator can improve the ability to generate and discriminate tiny blood vessels, making the domain-adaptive network more robust. The second-stage supervised training of arterial vessels was then performed on the translated arterial phase CT. In this process, we propose an orthogonal depth projection loss function to enhance the representation ability of the 3D U-shape segmentation network for the geometric information of the vessel model. The segmented venous vessels were also performed on venous phase CT in the second stage. Finally, we invited professional doctors to annotate arterial and venous vessels on the venous phase CT of the test set. The experimental results show that the segmentation accuracy of arterial and venous vessels on venous phase CT is 0.8454 and 0.8087, respectively. Our proposed framework can simultaneously achieve supervised segmentation of venous vessels and unsupervised segmentation of arterial vessels on venous phase CT. Our approach can be extended to other fields of medical segmentation, such as unsupervised domain adaptive segmentation of liver tumors at different CT phases, to facilitate the development of the community. [ABSTRACT FROM AUTHOR]

Background A predictive tool is required to identify the cancer-specific survival in rectal cancer (RC) patients who have opted to receive preoperative radiotherapy. Methods A database containing the data on RC patients' records of Surveillance, Epidemiology, and End Results (SEER) receiving surgery during 2000–2014 was selected. All patients received neoadjuvant radiotherapy (NR). The correlation of clinicopathological parameters was analyzed using the Chi-square test and the survival risk factors were analyzed using the Cox proportional hazards analysis (univariate and multivariate). Finally, the nomogram was developed and validated to visually represent an accurate prediction of the probability of 3- and 5-year cancer-specific survival (CSS) based on the screened variables of the cohort. Results 11,499 rectal cancer patients were included in our cohort. Patients' records were randomly allocated to either the development or validation cohorts based on an equal ratio (1:1). Performing the multivariate Cox regression analysis incorporating these variables in the development cohort determined 11 independent prognostic factors. Statistically significant differences were recorded among subgroups using log-rank tests, which confirmed the appropriateness and acceptability of factor stratifications. Then, the nomogram was constructed and its concordance index (C-index) values in the development cohort (0.720) and validation cohort (0.717) were evaluated to be higher (P<0.05) than those of the AJCC stage (0.631 and 0.633 respectively). Also, the 3-year AUC values of this nomogram were higher than those of the AJCC stage in both the development cohort (0.746 vs. 0.631) and the validation cohort (0.745 vs. 0.640). Using DCA curves, the predictive potential of the currently developed nomogram outperformed the conventional AJCC staging system. Conclusion The nomogram model might be a more reliable tool to predict prognosis accurately in rectal cancer patients receiving preoperative radiotherapy. [ABSTRACT FROM AUTHOR]

The low spatial frequency (LSF) component of visual information rapidly conveyed coarse information for global perception, while the high spatial frequency (HSF) component delivered fine-grained information for detailed analyses. The feedforward theorists deemed that a coarse-to-fine process was sufficient for a rapid scene recognition. Based on the response priming paradigm, the present study aimed to deeply explore how different spatial frequency interacted with each other during rapid scene recognition. The response priming paradigm posited that as long as the prime slide could be rapidly recognized, the prime-target system was behaviorally equivalent to a feedforward system. Adopting broad spatial frequency images, experiment 1 revealed a typical response priming effect. But in experiment 2, when the HSF and the LSF components of the same pictures were separately presented, neither the LSF-to-HSF sequence nor the HSF-to-LSF sequence reproduced the response priming effect. These results demonstrated that LSF or HSF component alone was not sufficient for rapid scene recognition and, further, that the integration of different spatial frequency needed some early feedback loops. These findings supported that the local recurrent processing loops among early visual cortex was involved during rapid scene recognition. • The role of different spatial frequencies during rapid scene recognition was explored. • Original natural images could rapidly task-related information. • Images with limited spatial frequencies failed to induce a vigorous priming effect. • A feedforward coarse-to-fine processing wasn't sufficient for rapid scene recognition. [ABSTRACT FROM AUTHOR]

As a country with abundant genetic resources of pigs, the domestication history of pigs in China and the adaptive evolution of Chinese pig breeds at different latitudes have rarely been elucidated at the genome-wide level. To fill this gap, we first assembled a high-quality chromosome-level genome of the Chenghua pig and used it as a benchmark to analyse the genomes of 272 samples from three genera of three continents. The divergence of the three species belonging to three genera, Phacochoerus africanus , Potamochoerus porcus , and Sus scrofa , was assessed. The introgression of pig breeds redefined that the migration routes were basically from southern China to central and southwestern China, then spread to eastern China, arrived in northern China, and finally reached Europe. The domestication of pigs in China occurred ∼12,000 years ago, earlier than the available Chinese archaeological domestication evidence. In addition, FBN1 and NR6A1 were identified in our study as candidate genes related to extreme skin thickness differences in Eurasian pig breeds and adaptive evolution at different latitudes in Chinese pig breeds, respectively. Our study provides a new resource for the pig genomic pool and refines our understanding of pig genetic diversity, domestication, migration, and adaptive evolution at different latitudes. [ABSTRACT FROM AUTHOR]

As a country with abundant genetic resources of pigs, the domestication history of pigs in China and the adaptive evolution of Chinese pig breeds at different latitudes have rarely been elucidated at the genome-wide level. To fill this gap, we first assembled a high-quality chromosome-level genome of the Chenghua pig and used it as a benchmark to analyse the genomes of 272 samples from three genera of three continents. The divergence of the three species belonging to three genera, Phacochoerus africanus , Potamochoerus porcus , and Sus scrofa , was assessed. The introgression of pig breeds redefined that the migration routes were basically from southern China to central and southwestern China, then spread to eastern China, arrived in northern China, and finally reached Europe. The domestication of pigs in China occurred ∼12,000 years ago, earlier than the available Chinese archaeological domestication evidence. In addition, FBN1 and NR6A1 were identified in our study as candidate genes related to extreme skin thickness differences in Eurasian pig breeds and adaptive evolution at different latitudes in Chinese pig breeds, respectively. Our study provides a new resource for the pig genomic pool and refines our understanding of pig genetic diversity, domestication, migration, and adaptive evolution at different latitudes. [ABSTRACT FROM AUTHOR]

The aim of our study was to explore the value of the 8th edition TNM staging system on evaluating the prognosis of colorectal carcinoid. Colorectal carcinoid patients between 1988 and 2015 were selected in the Surveillance, Epidemiology, and End Results Program (SEER) database for analysis. About 4286 patients with colorectal carcinoid tumors were identified, of which were carcinoid tumor NOS (n = 1726), neuroendocrine carcinoma (NEC) (n = 1346) and other carcinoid tumor (OCT) (n = 591). Worsening 10‐year CSS rates with increasing N status, M status, and SEER historic stage were demonstrated across all three above groups (all P <.05). In carcinoid tumor NOS, significant differences in CSS were found with increasing combined 8th AJCC stages (P <.001), except for that between stage II and stage III (10‐year CSS rate: 82.6% vs 84.3%, P =.68). While combined 8th TNM stage in NEC and OTC exhibited greater separations in CSS despite on‐going overlaps between groups. For carcinoid tumor NOS, stage II (HR = 3.37; 95% CI: 0.97‐11.76), and stage III (HR = 2.09; 95% CI: 0.51‐8.66) conferred no significant difference in CSS compared with stage I, while stage IV had an increasing HR of 5.09 (95% CI: 1.08‐24.08). Although combined 8th AJCC stage had a good ability to distinguish 10‐year CSS of patients with NEC or OCT, detailed 8th AJCC stage did not seem to be applicable. Detailed 8th AJCC categories of advanced stages in all the three groups conferred increased HRs with overlapping CIs. However, in the early and middle status, HRs did not increase with the increase of stages, or there was no difference in HRs between adjacent stages. Combined 8th TNM stage was not practical for judging the survival outcomes of colorectal carcinoid tumor NOS, especially in patients with stages II and III, but it provided useful prognostic information for NEC and OCT. However, for all carcinoid tumors, the prognostic values of detailed 8th AJCC stage were not enough accurate in the clinic. More optimized staging methods should be developed and validated in the future. [ABSTRACT FROM AUTHOR]