Metallic CoSb and Janus Co2AsSb monolayers as promising anode materials for metal-ion batteries.

Structural symmetry breaking plays a pivotal role in fine-tuning the properties of nano-layered materials. Here, based on the first-principles approaches we propose a Janus monolayer of metallic CoSb by breaking the out-of-plane structural symmetry. Specifically, within the CoSb monolayer by replacing the top-layer 'Sb' with 'As' atoms entirely, the Janus Co2AsSb monolayer can be formed, whose structure is confirmed via structural optimization and ab initio molecular dynamics simulations. Notably, the Janus Co2AsSb monolayer demonstrates stability at an elevated temperature of 1200 K, surpassing the stability of the CoSb monolayer, which remains stable only up to 900 K. We propose that both the CoSb and Janus Co2AsSb monolayers could serve as capable anode materials for power-driven metal-ion batteries, owing to their substantial theoretical capacity and robust binding strength. The theoretical specific capacities for Li/Na reach up to 1038.28/1186.60 mA h g-1 for CoSb, while Janus Co2AsSb demonstrates a marked improvement in electrochemical storage capacity of 3578.69/2215.38 mA h g-1 for Li/Na, representing a significant leap forward in this domain. The symmetry-breaking effect upgrades the CoSb monolayer, as a more viable contender for power-driven metal-ion batteries. Furthermore, electronic structure calculations indicate a notable charge transfer that augments the metallic nature, which would boost electrical conductivity. These simulations demonstrate that the CoSb and Janus Co2AsSb monolayers have immense potential for application in the design of metal-ion battery technologies.

Theoretical prediction and characterization of novel two-dimensional ternary tetradymite compounds La2X2Y (X = I, Br, Cl; Y = Ge, Te) as anode materials for metal-ion batteries.

Tetradymite compounds, such as Bi2Te3, crystallizing in rhombohedral structures have triggered tremendous research interest from the scientific community because of their intriguing properties. Herein, using the state-of-the-art first-principles calculations, we identify that La2X2Y (X = I, Br, Cl; Y = Ge, Te) nanosheets exhibit a ternary tetradymite-type structure with extraordinary electrical and electrochemical properties. It is first demonstrated that the layered La2X2Y compounds exhibit weak interlayer coupling with cleavage energies in the range of ∼0.28-0.38 J m-2, allowing the ready separation of monolayers that can be synthesized by mechanical exfoliation from their bulk counterparts. Next, we predict that La2X2Ge nanosheets exhibit a semiconducting nature, and upon physical realistic strain, a Dirac cone can be realized. These findings can be exploited in the transport properties. Furthermore, we comprehensively investigated the electrochemical properties of the predicted systems to evaluate their potential use in metal-ion (Li/Na) batteries. Our detailed analyses reveal that the Li (Na) adatoms are sufficiently mobile on the surface of the studied systems. For instance, the binding energy for the Li (Na) adatom on La2I2Ge is -2.24(-1.79) eV with a diffusion barrier of as small as ∼0.31(0.20) eV. Subsequently, the maximum theoretical specific capacity for Li (Na) reaches as high as 887(1064) mA h g-1, which can be attributed to a much higher storage capacity compared to previously identified 2D anode materials. These findings substantiate that the predicted nanosheets could be synthesized to explore their potential applications in future metal-ion batteries.

Black phosphorene/SnSe van der Waals heterostructure as a promising anchoring anode material for metal-ion batteries.

Black phosphorene (BP) is a glowing two-dimensional semiconducting layer material for cutting-edge microelectronics, with high carrier mobility and thickness-dependent band gap. Here, based on van der Waals (vdW)-corrected first-principles approaches, we investigated stacked BP/tin selenide (BP/SnSe) vdW heterostructure as an anode material for metal ion batteries, which exhibits a significant theoretical capacity, along with relatively durable binding strength compared to the constituent BP and SnSe monolayers. Our calculations demonstrated that the Li/Na adatom favors insertion into the interlayer region of BP/SnSe vdW heterostructure owing to synergistic interfacial effect, resulting in comparable diffusivity to the BP and SnSe monolayers. Subsequently, the theoretical specific capacities for Li/Na are found to be as high as 956.30 mAhg-1and 828.79 mAhg-1, respectively, which could be attributed to the much higher storage capacity of Li/Na adatoms in the BP/SnSe vdW heterostructure. Moreover, the electronic structure calculations reveal that a large amount of charge transfer assists in semiconductor-to-metallic transition upon lithiation/sodiation, ensuring good electrical conductivity. These simulations verify that the BP/SnSe vdW heterostructure has immense potential for application in the design of metal-ion battery technologies.

Improved reverse Monte Carlo analysis of optical property of Fe and Ni from reflection electron energy loss spectroscopy spectra.

The energy loss functions (ELFs) of Fe and Ni have been derived from measured reflection electron energy loss spectroscopy (REELS) spectra by a reverse Monte Carlo analysis in our previous work. In this work, we present further improvements of ELFs for these metals. For Fe, we have updated ELFs at primary electron energies of 2 keV and 3 keV in a wider photon energy region (0-180 eV) with a better accuracy, which is verified by sum rules. Regarding to Ni, we supplement the ELF at primary energy of 5 keV and we also improve the data accuracy at 3 keV. Applying these new and more accurate ELFs we present the optical constants and dielectric functions for the two metals. The improvements were highlighted by comparing our present results with the previous data.

[Comparison between laparoscopic-assisted natural orifice specimen extraction surgery and conventional laparoscopic surgery for left colorectal cancer: 5-year follow-up results of a randomized controlled study].

Objective: To evaluate the long-term efficacy of laparoscopic-assisted natural orifice specimen extraction surgery (NOSES) colectomy using Cai tube for treating left-sided colorectal cancer. Methods: This was a randomized controlled trial. Inclusion criteria were as follows: preoperative pathological diagnosis of left-sided colorectal adenocarcinoma (rectal, sigmoid colon, descending colon, or left transverse colon cancer with the caudad margin ≥8 cm from the anal margin); preoperative abdominal and pelvic computed tomography (or magnetic resonance imaging) showing maximum tumor diameter <4.5 cm; and BMI <30 kg/m2. Patients with synchronous multiple primary cancers or recurrent cancers, a history of neoadjuvant chemoradiotherapy, preoperative evidence of significant local infiltration, distant metastasis, or complications such as intestinal obstruction and intestinal perforation, or who were not otherwise considered suitable for laparoscopic surgery were excluded. A random number table was used to randomize sequential patients to NOSES surgery using Cai tube (non-assisted incision anal sleeve: patent number ZL201410168748.2) (NOSES group) or traditional laparoscopic-assisted surgery (CLS group). Relevant clinical data of the two groups of patients were analyzed, the main outcomes being disease-free survival, overall survival, overall recurrence rate, and local recurrence rate 5 years after surgery. Results: Patients in both study groups completed the surgery successfully with no requirement for additional surgery. After mean 70 (7-83) months postoperative follow-up, the 5-year overall postoperative survival in the NOSES and CLS groups was 90.0% and 83.3%, respectively (P=0.455); disease free survival was 90.0% and 83.3%, respectively (P=0.455); overall recurrence rate 6.6% and 10.0%, respectively (P=0.625); and local recurrence rate both were 3.3% (P=0.990), respectively. None of these differences was statistically significant. Conclusions: NOSES and CLS have similar long-term efficacy, and NOSES deserves to be used in clinical practice.

A theoretical characterization method for non-spherical core-shell nanoparticles by XPS.

Core-shell nanoparticles (NPs) are active research areas for their unique properties and wide applications. By changing the elemental composition in the core and shell, a series of core-shell NPs with specific functions can be obtained, where the sizes of the core and shell also influence the properties. X-ray photoelectron spectroscopy (XPS) is useful in this context as a means of quantitatively analyzing such NPs. The empirical formula proposed by Shard [J. Phys. Chem. C, 2012, 116(31), 16806-16813] for calculating the shell thickness of the spherical core-shell NPs has been verified by Powell et al. [J. Phys. Chem. C, 2016, 120(39), 22730-22738] through a simulation of XPS with Simulation of Electron Spectra for Surface Analysis (SESSA) software. However, real core-shell NPs are not necessarily ideal spheres; such NPs can have rich shapes and uneven thicknesses. This work aims to extend the Shard formula to non-ideal core-shell NPs. We have used a Monte Carlo simulation method to study the XPS signal variation with the shell thickness for several modeled non-spherical shapes of core-shell NPs including some complex geometric structures which are numerically constructed with finite-element triangular meshes. Five types of non-spherical shapes, i.e. egg, ellipsoid, rod, rough-surface, and star shapes, are considered, while the size parameters are varied over a wide range. The equivalent radius and equivalent thickness are defined to characterize the average size of the nanoparticles for the use of the Shard formula. We have thus derived an extended Shard formula for the specific core-shell NPs, with which the relative error between the predicted shell thickness and the real thickness can be reduced to less than 10%.

Exploring the absolute yield curve of secondary electrons using machine learning methods.

Knowledge of absolute secondary electron yield (δ) is important for various applications of electron emission materials. Besides, it is also crucial to know the dependence of δ on primary electron energy Ep and material properties like atomic number Z. The available experimental database of δ reveals a large discrepancy among the measurement data, while the oversimplified semi-empirical theories of secondary electron emission can only present the general shape of the yield curve but not the absolute yield value. This limits not only the validation of a Monte Carlo model for theoretical simulations but also presents large uncertainties in the applications of different materials for various purposes. In applications, it is highly desirable to have the knowledge of the absolute yield of a material. Therefore, it is highly desirable to establish the relationship of the absolute yield with material and electron energy based on the available experimental data. Recently, machine learning (ML) methods have been increasingly used for the prediction of material properties mainly based on the atomistic calculations with the first-principles theory. We propose here the application of ML models to a material property study, starting with experimental observations and unfolding the relationship of δ with basic material properties and primary electron energy. Our ML models are able to predict δ(Ep)-curve covering a wide energy range of 10 eV-30 keV for unknown elements within the uncertainty range of the experimental data and can suggest more reliable data among the scattered experimental data.

[Specimen extraction through natural orifices with Cai tubes in gastrointestinal surgery: a single-institute series of 234 cases].

Objective: To investigate the feasibility of Cai tube-assisted natural orifice specimen extraction surgery (NOSES) in gastrointestinal surgery. Methods: This was a descriptive case-series study. Inclusion criteria: (1) colorectal or gastric cancer diagnosed by preoperative pathological examination or redundant sigmoid or transverse colon detected by barium enema; (2) indications for laparoscopic surgery; (3) body mass index <30 kg/m2 (transanal surgery) and 35 kg/m2 (transvaginal surgery); (4) no vaginal stenosis or adhesions in female patients undergoing transvaginal specimen extraction; and (5) patients with redundant colon aged 18-70 years and a history of intractable constipation for more than 10 years. Exclusion criteria: (1) colorectal cancer with intestinal perforation or obstruction, or gastric cancer with gastric perforation, gastric hemorrhage, or pyloric obstruction; (2) simultaneous resection of lung, bone, or liver metastases ; (3) history of major abdominal surgery or intestinal adhesions; and (4) incomplete clinical data. From January 2014 to October 2022, 209 patients with gastrointestinal tumors and 25 with redundant colons who met the above criteria were treated by NOSES utilizing a Cai tube (China invention patent number:ZL201410168748.2) in the Department of Gastrointestinal Surgery, Zhongshan Hospital, Xiamen University. The procedures included eversion and pull-out NOSES radical resection in 14 patients with middle and low rectal cancer, NOSES radical left hemicolectomy in 171 patients with left-sided colorectal cancer, NOSES radical right hemicolectomy in 12 patients with right-sided colon cancer, NOSES systematic mesogastric resection in 12 patients with gastric cancer, and NOSES subtotal colectomy in 25 patients with redundant colons. All specimens were collected by using an in-house-made anal cannula (Cai tube) with no auxiliary incisions. The primary outcomes included 1-year recurrence-free survival (RFS) and postoperative complications. Results: Among 234 patients, 116 were male and 118 were female. The mean age was (56.6±10.9) years. NOSES was successfully completed in all patients without conversion to open surgery or procedure-related death. The negative rate of circumferential resection margin was 98.8% (169/171) with both two positive cases having left-sided colorectal cancer. Postoperative complications occurred in 37 patients (15.8%), including 11 cases (4.7%) of anastomotic leakage, 3 cases(1.3%) of anastomotic bleeding, 2 cases (0.9%) of intraperitoneal bleeding, 4 cases (1.7%) of abdominal infection, and 8 cases (3.4%) of pulmonary infection. Reoperations were required in 7 patients (3.0%), all of whom consented to creation of an ileostomy after anastomotic leakage. The total readmission rate within 30 days after surgery was 0.9% (2/234). After a follow-up of (18.3±3.6) months, the 1-year RFS was 94.7%. Five of 209 patients (2.4%) with gastrointestinal tumors had local recurrence, all of which was anastomotic recurrence. Sixteen patients (7.7%) developed distant metastases, including liver metastases(n=8), lung metastases(n=6), and bone metastases (n=2). Conclusion: NOSES assisted by Cai tube is feasible and safe in radical resection of gastrointestinal tumors and subtotal colectomy for redundant colon.

Energy loss function of samarium.

We present a combined experimental and theoretical work to obtain the energy loss function (ELF) or the excitation spectrum of samarium in the energy loss range between 3 and 200 eV. At low loss energies, the plasmon excitation is clearly identified and the surface and bulk contributions are distinguished. For the precise analysis the frequency-dependent energy loss function and the related optical constants (n and k) of samarium were extracted from the measured reflection electron energy loss spectroscopy (REELS) spectra by the reverse Monte Carlo method. The ps- and f-sum rules with final ELF fulfils the nominal values with 0.2% and 2.5% accuracy, respectively. It was found that a bulk mode locates at 14.2 eV with the peak width ~6 eV and the corresponding broaden surface plasmon mode locates at energies of 5-11 eV.

Influence of energy loss function to the Monte Carlo simulated electron backscattering coefficient.

We report an improved calculation of the electron backscattering coefficients (BSCs) for beryllium, molybdenum and tungsten at electron energies of 0.1-100 keV based on an up-to-date Monte Carlo simulation method with different input of energy loss function (ELF) data. The electron inelastic cross-section is derived from the relativistic dielectric functional formalism, where the full Penn's algorithm is applied for the extension of the ELF from the optical limit of [Formula: see text] into the [Formula: see text]-plane. We have found that the accuracy of energy loss function may affect largely the calculated BSC. We also show that this has close relationship with the f- and ps-sum rules.

[Comparison between laparoscopic-assisted natural orifice specimen extraction surgery and conventional laparoscopic surgery for left colorectal cancer: a randomized controlled study with 3-year follow-up results].

Objective: To evaluate the mid-term efficacy of laparoscopic-assisted natural orifice specimen extraction surgery (NOSES) colectomy using the Cai tube in the treatment of left colorectal cancer. Methods: A prospective randomized control trial (China Clinical Trials Registration Number: ChiCTR-OOR-15007060) was performed. Sixty patients with left colorectal cancer at Department of Gastrointestinal Surgery of Zhongshan Hospital from September 2015 to August 2017 were prospectively enrolled. Case inclusion criteria: (1) left colorectal adenocarcinoma (rectal cancer with distance ≥ 8 cm from tumor low margin to anal edge, sigmoid colon cancer, descending colon cancer and left transverse colon cancer) confirmed by preoperative pathology; (2) satisfactory conditions of conventional laparoscopic surgery; (3) maximum diameter of the tumor < 4.5 cm confirmed by preoperative abdominal and pelvic CT or MRI; (4) BMI < 30 kg/m2. Case exclusion criteria: (1) benign lesions, mucinous adenocarcinoma, signet-ring cell carcinoma and other special pathological types of tumors confirmed by preoperative pathological examination; (2) multiple or recurrent cancers; (3) with a history of neoadjuvant chemoradiotherapy; (4) obvious regional infiltration or distant metastasis indicated by preoperative imaging examination; (5) intestinal obstruction, intestinal perforation, etc. Participants were randomly assigned to NOSES group (using the Cai tube) and conventional laparoscopy (CL) group by random number table method. Clinical data between two groups were compared and analyzed, including perioperative conditions, tumor exfoliation cell detection and bacterial culture results of intraperitoneal lavage fluid, postoperative complications (Clavien-Dindo grading), postoperative pain [visual simulation scoring (VAS) assessment], anal function (Kirwan anal function grading assessment), and postoperative 3-year disease-free survival (DFS), overall survival (OS), overall recurrence rate, and local recurrence rate. Results: A total of 60 patients were enrolled, with 30 in the NOSES group and 30 in the CL group. All the patients in the NOSES group successfully completed operation with Cai tube. Baseline data between the two groups were not significantly different (all P>0.05). There were no statistically significant differences between two groups in conversion rate to open surgery, number of lymph node harivested, proximal and distal resection margin of tumor, negative rate of circumferential margin, operation time, blood loss, inflammatory indexes, postoperative anal function, postoperative hospital stay, hospitalization cost, morbidity of postoperative complications (Clavien-Dindo grade II or above) (all P>0.05). Compared to the CL group, the NOSES group had lower maximum postoperative VAS score (2.5±0.3 vs. 5.1±0.4, t=3.187, P<0.01), and fewer use of additional postoperative analgesia [6.7% (2/30) vs. 33.3% (10/30),χ2=6.670, P=0.02]. The postoperative time to gas passage was shorter in the NOSES group [(2.2±1.4) days vs. (3.1±1.2) days,P=0.026]. No tumor cells and bacterial contamination were found in abdominal lavage fluid before and after operation in either group. The anal function at postoperative 3-month of all the patients in the NOSES group was Kirwan grade I to II, while in the CL group, anal function of 2 cases (6.7%) was Kirwan grade III, and of 28 cases was also Kirwan grade I to II, whose difference was not statistically significant (P>0.05). In the NOSES group and the CL group, 3-year DFS was 96.7% and 83.3% (P=0.090), OS was 100% and 90% (P=0.096), overall recurrence rate was 3.3% and 10.0% (P=0.166), and local recurrence rate was 3.3% and 3.3% (P=0.999), respectively, whose differences were not statistically significant (all P>0.05). Conclusions: In the treatment of left colorectal cancer, compared with conventional laparoscopic colectomy, NOSES colectomy using Cai tube exhibits less scar, less postoperative pain, shorter recovery of gastrointestinal function, and similar mid-term outcomes. Given proper surgical indications, the surgical procedure is safe and feasible.

Multislice method based full-space analysis on mechanical interaction of electron vortex beam with a crystalline particle.

A full-space analysis based on the multislice method is presented and has been applied to the simulation of mechanical interaction of electron vortex beam with a nanoparticle. The moment acting on the particle is calculated and presented as a moment map. We have calculated the total torque and compared it with the result from orbital angular momentum analysis. The thickness dependent torque and angular momentum are derived and discussed for different incident energies, convergence angles and angular momenta of the incident electron vortex beam. For different incident beams, the enhanced torque caused by diffraction enhancement is discussed. The oscillation behavior of the torque and angular momentum on depth is explained by a channeling theory. A comparison of thickness dependent angular momentum between the proposed analysis and conventional orbital angular momentum analysis in both the multislice method and the Bloch wave method is presented and discussed.

Optical properties of amorphous carbon determined by reflection electron energy loss spectroscopy spectra.

We present the combined experimental and theoretical investigations of the optical properties of amorphous carbon. The reflection electron energy loss spectra (REELS) spectra of carbon were measured using a cylindrical mirror analyzer under ultrahigh vacuum conditions at primary electron energies of 750, 1000 and 1300 eV. The energy loss function and thereby the refractive index n and the extinction coefficient k were determined from these REELS spectra in a wide loss energy range of 2-200 eV by applying our reverse Monte Carlo method. The high accuracy of the obtained optical constants is justified with the ps- and f-sum rules. We found that our present optical constants of amorphous carbon fulfill the sum rules with the highest accuracy compared with the previously published data. Therefore, we highly recommend to replace the previous data with the present ones for practical applications. Moreover, we present the atomic scattering factors of amorphous carbon obtained from the dielectric function to predict its optical constants at a given density.

Charging effect induced by electron beam irradiation: a review.

Charging effect frequently occurs when characterizing nonconductive materials using electrons as probes and/or signals and can impede the acquisition of useful information about the material under investigation. It is not adequate to investigate it merely by experiments, but theoretical investigations, for which the Monte Carlo method is a suitable tool, are also necessary. In this paper we review Monte Carlo simulations and selected experiments, intending to provide general insight into the charging effects induced by electron beam irradiation. We will introduce categories of the charging effect, the theoretical framework that is adopted in Monte Carlo modeling of the charging effect and present some typical simulation results. At last, with the knowledge on charging effect imparted by the above contents, we will discuss the measures that can be used for minimizing it.

Black phosphorene/blue phosphorene van der Waals heterostructure: a potential anode material for lithium-ion batteries.

Van der Waals (vdW) heterostructure-based electrodes have invoked tremendous research interest due to their intriguing properties and their capability to break the limitations of the restricted properties of single-material systems. Herein, based on first-principles approaches, we propose that the black phosphorene/blue phosphorene (BLK-P/BLE-P) vdW heterostructure can be a capable anode material for power-driving lithium-ion batteries (LIBs), as it exhibits a large theoretical capacity, together with a relatively strong binding strength compared with the individual BLK-P and BLE-P monolayers. Our calculation results show that the Li adatom prefers to intercalate into the interlayer of the BLK-P/BLE-P vdW heterostructure due to the synergistic interfacial effect, resulting in a high binding strength and a diffusivity comparable to the BLK-P and BLE-P monolayers. Subsequently, the theoretical specific capacity is found to be as high as 552.8 mA h g-1, which can be attributed to the much higher storage capacity of Li adatoms in the BLK-P/BLE-P vdW heterostructure. Furthermore, electronic structure calculations reveal that a large amount of charge transfer assists in semiconductor to metallic transition upon lithiation, which would ensure good electrical conductivity. These simulations prove that the BLK-P/BLE-P heterostructure has great potential in LIBs and is essential for future battery design.

Ensemble machine learning methods: predicting electron stopping powers from a small experimental database.

Electron stopping power (SP) is of great importance in theoretical and applied research areas specifically for Monte Carlo simulation studies in many microanalysis and surface analysis techniques, radiation dosimetry, and the design of particle detectors. However, experimental data are available for a dozen elemental materials only. On the other hand, the Bethe analytical expression of the SP is applicable at high energies only whereas no generally accepted formula exists at lower energies. We employed ensemble machine learning (ML) methods with the available experimental database for the prediction of SPs of electrons with energies from 100 keV down to 1 eV, in elements over the entire periodic table. With a small training database for electron SPs, we applied various algorithms individually as well as their ensembles, which have the credibility to enhance the prediction accuracy in the case of a small training database. Based on the model's performance evaluation tests, we concluded that the stacked generalization is more accurate than the individual algorithms. Using this method, we were able to predict the electron SPs for 54 elements (in total) including 12 elements that were present in the training database as well as for 42 elements beyond the training database over a wide energy range (1 eV to 100 keV). Compared to other theoretical approaches, the ML predicted SPs show very good agreement with the available experimental data at all energies. Moreover, unlike other theoretical approaches, the ML model does not need dielectric function data and other physical parameters which involve complex calculations. Using our ML model, we have predicted SPs for a further 14 elements for which no theoretical SPs are available because of the lack of good dielectric function data.

Individual separation of surface, bulk and Begrenzungs effect components in the surface electron energy spectra.

We present the first theoretical recipe for the clear and individual separation of surface, bulk and Begrenzungs effect components in surface electron energy spectra. The procedure ends up with the spectral contributions originated from surface and bulk-Begrenzungs excitations by using a simple method for dealing with the mixed scatterings. As an example, the model is applied to the reflection electron energy loss spectroscopy spectrum of Si. The electron spectroscopy techniques can directly use the present calculation schema to identify the origin of the electron signals from a sample. Our model provides the possibility for the detailed and accurate quantitative analysis of REELS spectra.

Imaging simulation of charged nanowires in TEM with large defocus distance.

In transmission electron microscope (TEM), both the amplitude and the phase of electron beam change when electrons traverse a specimen. The amplitude is easily obtained by the square root of the intensity of a TEM image, while the phase affects defocused images. In order to obtain the phase map and verify the theoretical model of the interaction between electron beam and specimen, a lot of simulations have to be performed by researchers. In this work, we have simulated defocus images of a SiC nanowire in TEM with the method of electron optics. Mean inner potential and charge distribution on the nanowire have been considered in the simulation. Besides, due to electron scattering, coherence loss of the electron beam has been introduced. A dynamic process with Bayesian optimization was used in the simulation. With the infocus image as input and by adjusting fitting parameters, the defocus image is determined with a reasonable charge distribution. The calculated defocus images are in a good agreement with the experimental ones. Here, we present a complete solution and verification method for solving nanoscale charge distribution in TEM.

Antibiotics in marine aquaculture farms surrounding Laizhou Bay, Bohai Sea: Distribution characteristics considering various culture modes and organism species.

This study mainly investigated the distribution characteristics and risk assessment of 14 antibiotics in typical marine aquaculture farms surrounding the Bohai Sea. The effects of various culture modes (outdoor pond culture, recirculating water culture, greenhouse pond culture, raft culture, cage culture and bottom sowing culture), and diverse cultured organism species such as fish (grouper, bass, pike and turbot), mollusk (oyster, scallop, conch and mussel) and sea cucumber on the distribution of antibiotics in different mariculture pond matrices (seawater, sediment/biofilm and organism) were studied. In addition, antibiotic pollution levels in various matrices (water, sediment, organism and feed) from different mariculture areas surrounding the Bohai Sea and the Yellow Sea were compared. The biofilm on the inner wall of greenhouse pond was more capable of accumulating antibiotics than the biofilm attached to the rope for raft culture and net for cage culture, and other culture sediments. The antibiotic concentration level in the culture matrices (water, sediment/biofilm and organism) was the highest under greenhouse pond culture mode, and that under the industrial recirculating water culture mode was the lowest. Antibiotic concentration in culture matrices of fish ponds was higher than that of sea cucumber ponds and mollusk ponds. The levels of antibiotics in water and sediment from marine aquaculture farms in Laizhou (Bohai Sea coast) were higher than those in Haiyang and Jimo (Yellow Sea coast). Enrofloxacin in turbot might cause considerable harm to human health, and the risk of antibiotics in other seafood could be ignored. Antibiotic ecological risks and resistance risks were generally low in water. Fluoroquinolones posed medium to high ecological risks in the natural receiving water around the mariculture farm. Trimethoprim and enrofloxacin showed relatively high antibiotic resistance risks in mariculture water and natural water, which might exert selective pressure on the bacterial community in the environment.

[Correlation between elevation of brachial artery pulse pressure increased and coronary heart disease in different genders].

Objective: To explore the relationship between elevation of brachial pulse pressure and coronary heart disease in different genders. Methods: A total of 5 116 inpatients with suspected stable coronary heart disease were consecutively enrolled from December 2011 to June 2017 in the Affiliated Hospital of Chengde Medical College, and divided into coronary heart disease group (n=3 694) and non-coronary heart disease group (n=1 422). The clinical data of all inpatients were collected. A binary logistic regression model of coronary heart disease in different genders were separately established. Results: The morbidity of hypertension, dyslipidemia, type 2 diabetes, ischemic stroke and elevated pulse pressure were all higher in the coronary heart disease group than those in the non-coronary heart disease group (all P<0.05). The area under curve (AUC) of pulse pressure in the male group was 0.540, with an optimal diagnostic threshold of 50 mmHg. The AUC of pulse pressure in the female group was 0.612, with an optimal diagnostic threshold of 60 mmHg. Besides hypertension, type 2 diabetes, increase of low-density lipoprotein cholesterol, ischemic stroke, smoking, and aging, elevated pulse pressure was also an independent risk factor for coronary heart disease in both male and female groups (all P<0.05). Additionally, the risk of elevated pulse pressure for coronary heart disease was higher in female group than that of male group (odds ratio (OR): 1.741 vs 1.284, P<0.05). Conclusion: Elevated pulse pressure may be a new risk factor for coronary heart disease, and its risk for coronary heart disease is higher in women than in men.