Atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering correction

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such events.These pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric transmission.To quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering correction.The proposed method is an improvement over the traditional analytical method that only computes direct-transmission X-rays.The traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo method.Our improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain scenarios.Moreover,its computation time is 48,000 times faster than that of the Monte Carlo method.These results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

Clinical comprehensive treatment protocol for managing diabetic foot ulcers:A retrospective cohort study

BACKGROUND Diabetic foot ulcers(DFUs)are a common complication of diabetes,often leading to severe infections,amputations,and reduced quality of life.The current standard treatment protocols for DFUs have limitations in promoting efficient wound healing and preventing complications.A comprehensive treatment approach targeting multiple aspects of wound care may offer improved outcomes for patients with DFUs.The hypothesis of this study is that a comprehensive treatment protocol for DFUs will result in faster wound healing,reduced amputation rates,and improved overall patient outcomes compared to standard treatment protocols.AIM To compare the efficacy and safety of a comprehensive treatment protocol for DFUs with those of the standard treatment protocol.METHODS This retrospective study included 62 patients with DFUs,enrolled between January 2022 and January 2024,randomly assigned to the experimental(n=32)or control(n=30)group.The experimental group received a comprehensive treatment comprising blood circulation improvement,debridement,vacuum sealing drainage,recombinant human epidermal growth factor and anti-inflammatory dressing,and skin grafting.The control group received standard treatment,which included wound cleaning and dressing,antibiotics administration,and surgical debridement or amputation,if necessary.Time taken to reduce the white blood cell count,number of dressing changes,wound healing rate and time,and amputation rate were assessed.RESULTS The experimental group exhibited significantly better outcomes than those of the control group in terms of the wound healing rate,wound healing time,and amputation rate.Additionally,the comprehensive treatment protocol was safe and well tolerated by the patients.CONCLUSION Comprehensive treatment for DFUs is more effective than standard treatment,promoting granulation tissue growth,shortening hospitalization time,reducing pain and amputation rate,improving wound healing,and enhancing quality of life.

Effects of intestinal mucosal blood flow and motility on intestinal mucosa

AIM： To investigate the role of intestinal mucosal blood flow （IMBF） and motility in the damage of intestinal mucosal barrier in rats with traumatic brain injury. METHODS： Sixty-four healthy male Wistar rats were divided randomly into two groups： traumatic brain injury （TBI） group （n = 32）, rats with traumatic brain injury; and control group （n = 32）, rats with sham-operation. Each group was divided into four subgroups （n = 8） as 6, 12, 24 and 48 h after operation. Intestinal motility was measured by the propulsion ratio of a semi-solid colored marker （carbon-ink）. IMBF was measured with the laser-Doppler technique. Endotoxin and D-xylose levels in plasma were measured to evaluate the change of intestinal mucosal barrier function following TBI. RESULTS： The level of endotoxin was significantly higher in TBI group than in the control group at each time point （0.382 ± 0.014 EU/mL vs 0.102 ± 0.007 EU/mL, 0.466 ± 0.018 EU/mL vs 0.114 ± 0.021 EU/mL, 0.478± 0.029 EU/mL vs 0.112 ±- 0.018 EU/mL and 0.412± 0.036 EU/mL vs 0.108 ±0.011 EU/mL, P 〈 0.05）. D-xylose concentrations in plasma in TBI group were significantly higher than in the control group （6.68 ± 2.37 mmol/L vs 3.66 ±1.07 retool/L, 8.51 ± 2.69 mmol/L vs 3.15 ＋ 0.95 mmol/L, 11.68 ±3.24 mmol/L vs 3.78 ± 1.12 mmol/L and 10.23 ± 2.83 mmol/L vs 3.34 ± 1.23 mmol/L, P 〈 0.05）. The IMBF in TBI group was significantly lower than that in the control group （38.5 ± 2.8 PU vs 45.6 ± 4.6 PU, 25.2 ± 3.1 PU vs 48.2 ± 5.3 PU, 21.5 ± 2.7 PU vs 44.9 ± 2.8 PU, 29. 4 ± 3.8 PU vs 46.7 ± 3.2 PU） （P 〈 0.05）. Significant decelerations of intestinal propulsion ratio in T8I groups were found compared with the control group （0.48% ± 0.06% vs 0.62%± 0.03%, 0.37% ±0.05% vs 0.64% ± 0.01%, 0.39% ± 0.07% vs 0.63% =1= 0.05% and 0.46% ± 0.03% vs 0.65% ± 0.02%） （P 〈 0.05）. CONCLUSION： The intestinal mucosal permeability is increased obviously in TBI rats. Decrease of intestinal motility and IMBF occur early in TBI, both are important pathogenic factors for stress-related damage of the intestinal mucosal barrier in TBI.

Effects of Radiofrequency Ablation on Lymphocyte Subsets and Type 1/Type 2 T Cell Subpopulations in Patients with Hepatocellular Carcinoma

Objective： To evaluate whether radiofrequency ablation （RFA） might have an influence on immune status in hepatocellular carcinoma （HCC） patients. Methods： We measured the T lymphocytes, B lymphocyte and NK cells, and determined the population of Thl, Th2, Tcl and Tc2 of peripheral blood samples taken from 26 HCC patients before and after RFA. Results： The proportion of Typel cells （Thl and Tcl） and NK cells were significantly increased after RFA, especially in patients of the following subgroups： male, age〉55 years, pathological grade Ⅰ-Ⅱ tumor, clinical stage Ⅰ-Ⅱ or Child-Pugh A and B. Conclusion： TypeⅠ cells and NK cells in HCC patients were increased in a short period after RFA.

Digital single-operator cholangioscopy for biliary stricture after cadaveric liver transplantation

BACKGROUND Biliary strictures after liver transplantation(LT)remain clinically arduous and challenging situations,and endoscopic retrograde cholangiopancreatography(ERCP)has been considered as the gold standard for the management of biliary strictures after LT.Nevertheless,in the treatment of biliary strictures after LT with ERCP,many studies show that there is a large variation in diagnostic accuracy and therapeutic success rate.Digital single-operator peroral cholangioscopy(DSOC)is considered a valuable diagnostic modality for indeterminate biliary strictures.AIM To evaluate DSOC in addition to ERCP for management of biliary strictures after LT.METHODS Nineteen patients with duct-to-duct biliary reconstruction who underwent ERCP for suspected biliary complications between March 2019 and March 2020 at Beijing Chaoyang Hospital,Capital Medical University,were consecutively enrolled in this observational study.After evaluating bile ducts using fluoroscopy,cholangioscopy using a modern digital single-operator cholangioscopy system(SpyGlass DS^(TM))was performed during the same procedure with patients under conscious sedation.All patients received peri-interventional antibiotic prophylaxis.Biliary strictures after LT were classified according to the manifestations of choledochoscopic strictures and the manifestations of transplanted hepatobiliary ducts.RESULTS Twenty-one biliary strictures were found in a total of 19 patients,among which anastomotic strictures were evident in 18(94.7%)patients,while non-anastomotic strictures in 2(10.5%),and space-occupying lesions in 1(5.3%).Stones were found in 11(57.9%)and loose sutures in 8(42.1%).A benefit of cholangioscopy was seen in 15(78.9%)patients.Cholangioscopy was crucial for selective guidewire placement prior to planned intervention in 4 patients.It was instrumental in identifying biliary stone and/or loose sutures in 9 patients in whom ERCP failed.It also provided a direct vision for laser lithotripsy.A spaceoccupying lesion in the bile duct was diagnosed by cholangioscopy in one patient.Patients with biliary stricture after LT displayed four types:(A)mild inflammatory change(n=9);(B)acute inflammatory change edema,ulceration,and sloughing(n=3);(C)chronic inflammatory change;and(D)acute suppurative change.Complications were seen in three patients with post-interventional cholangitis and another three with hyperamylasemia.CONCLUSION DSOC can provide important diagnostic information,helping plan and perform interventional procedures in LT-related biliary strictures.

Effect of BRM S1 expression on proliferation, migration and adhesion of mouse forestomach carcinoma

Objective: To discuss the ef ect of BRMS1 on the proliferation, migration and adhesion of mouse forestomach carcinoma(MFC). Methods: The constructed p CMV-myc-BRMS1 recombinant plasmid and blank plasmid were transfected into mouse forestomach carcinoma. MTT method was employed to measure the activity of gastric cancer cell; the scratch assay and Transwell assay to measure the migration and invasion of gastric cancer cell; the adhesion assay to measure the adhesion of gastric cancer cell; while the Western blot assay to measure the expression of The NF-毷B signal pathway, downstream matrix metalloproteinase(MMP-2), MMP-9 and osteopontin and E-cadherin in the gastric cancer cell. Besides, the transplanted animal model of gastric cancer in mice was constructed to measure the size of tumor xenograft. Results: Results of MTT assay showed that, compared with the empty vector control group, the activity of gastric cancer cell was not af ected in the BRMS1 transfection group. The improved expression of BRMS1 could inhibit the adhesion, migration and invasion of gastric cancer cell(P<0.01). Besides, compared with the empty vector control group, the phosphorylation of NF-毷B p65 and I毷Bα was reduced in the BRMS1 transfection group, with the decreased expression of MMP 2, MMP 9 and osteopontin and the increased expression of E-cadherin(P<0.01). Results of animal experiment also showed that the expression of BRMS1 did not af ect the transplanted tumor. Conclusions: The expression of BRMS1 can signii cantly inhibit the adhesion, migration, invasion and metastasis of MCF gastric cancer cell, which is related to The NF-毷B signal pathway.

Self-starting all-fiber PM Er:laser mode locked by a biased nonlinear amplifying loop mirror

A compact all-fiber polarization-maintaining Er:laser using a nonlinear amplifying loop mirror is reported. Fundamental single-pulse mode-locking operation can always self start, with a cavity round-trip decreased from ~ 4.7 m to~ 1.7 m. When the pulse repetition rate is 121.0328 MHz, output pulse is measured to have a center wavelength/3-d B spectral bandwidth/radio frequency signal to noise ratio(SNR)/pulse width of 1571.65 nm/18.70 nm/80 d B/477 fs, respectively. Besides, three states including the exponential growth, damping state, and steady state are investigated through the build-up process both experimentally and numerically. Excellent stability of this compact Er:laser is further evaluated,demonstrating that it can be an easy-fabrication maintenance-free ultrafast candidate for the scientific area of this kind.

Effect of boron addition on the microstructure and stress-rupture properties of directionally solidified superalloys

This study is focused on the effect of boron addition, in the range of 0.0007wt% to 0.03wt%, on the microstructure and stress-rupture properties of a directionally solidified superalloy. With increasing boron content in the as-cast alloys, there is an increase in the fraction of the γ′/γ eutectic and block borides precipitate around the γ′/γ eutectic. At a high boron content of 0.03wt%, there is precipitation of lamellar borides. Upon heat treatment, fine block borides tend to precipitate at grain boundaries with increasing boron content. Overall, the rupture life of the directionally solidified superalloy is significantly improved with the addition of nominal content of boron. However, the rupture life decreases when the boron content exceeds 0.03wt%.

Effect of Dual Trigger In Vitro Fertilization and Intracytoplasmic Sperm Injection During the Gonadotropin-releasing Hormone-Antagonist Cycle on Final Oocyte Maturation and Cumulative Live Birth Rate in Women with Diminished Ovarian Reserve

Objective It is well known that a dual trigger treatment can improve clinical outcomes of in vitro fertilization(IVF)in high or normal ovarian responders.However,it is not clear whether dual triggering also benefits patients with diminished ovarian reserve(DOR).The aim of this study was to investigate whether a dual trigger treatment of gonadotropin-releasing hormone(GnRH)agonist combined with human chorionic gonadotropin(hCG)for final follicular maturation improves the cumulative live birth rate(CLBR)during the GnRH-antagonist cycle in patients with DOR.Methods This retrospective study included patients with DOR who received a GnRH-antagonist protocol during IVF and intracytoplasmic sperm injection(IVF-ICSI)cycles at Peking University People’s Hospital from January 1,2017 through December 31,2017.Oocyte maturation was triggered by GnRH combined with hCG(n=110)or hCG alone(n=71).Embryos were transferred on the third day after oocyte retrieval or during a subsequent freeze-thaw cycle.Patients were followed up for 3 years.Results The dual trigger treatment did not affect CLBR,which is an overall determinant of the success rate of assisted reproductive technology(ART).Women in the dual trigger group had significantly higher rates of fertilization than those in the hCG group(90.1%vs.83.9%,P=0.040).Conclusion Dual trigger with GnRH agonist and hCG did not improve CLBR in patients with DOR,but did slightly improve fertilization rate,oocyte count,and embryo quality.

Coal matrix deformation characteristics in the process of carbon dioxide displacing different gas saturation coal-bed methane

It is fundamental that changes in coal reservoir permeability are researched, in particular, the accurate determination of variations in the coal matrix caused by CO2 replacing CH4 at different gas saturation conditions. Based on the surface free energy, the extended Langmuir isothermal adsorption model, combined with CO2 replacing CH4 in experimental trials, and calling on the more general principles and characteristics of the field, mathematical models describing the coal matrix as it undergoes different processes such as CO2 injection and desorption were established. Combined with laboratory data about CO2 replacement under different methane saturation conditions, a law governing the variations in coal matrix CO2 replacement under different methane gas saturation conditions was obtained. The results showed that： in the injection process, the coal matrix expansion rate caused by CO2 or CH4 was exponentially increased with the CO2 pressure increase, the expansion caused by CO2 was far greater than the expansion caused by CH4 in the desorption process, the coal matrix shrinkage caused by CO2 or CH4 was exponentially increased with the pressure decrease, the shrinkage caused by CO2 was larger than the shrinkage caused by CH4 under the same pressure and different gas saturation, the total shrinkage in the desorption process in the coal matrix was greater than the total expansion in the injection process. At higher gas saturations, the total coal matrix shrinkage volume exceeded the total expansion corresponding to pressure points higher in the desorption process.

Microstructure and stress rupture properties of polycrystal and directionally solidified castings of nickel-based superalloys

A new directionally solidified Ni-based superalloy DZ24, which is a modification of K24 alloy without rare and expensive elemental additions, such as Ta and Hf, was studied in this paper. The microstructure and stress rupture properties of conventionally cast and directionally solidified superalloys were comparatively analyzed. It is indicated that the microstructure of K24 alloy is composed of γ, γ＇, γ/γ＇ eutectics and MC carbides. Compared with the microstructure of K24 polycrystalline alloy, γ/γ＇ eutectic completely dissolves into the γ matrix, the fine and regular γ＇ phase reprecipitates, and MC carbides decompose to M6C/M23C6 carbides after heat treatment in DZ24 alloy. The rupture life of DZ24 alloy is two times longer than that of K24 alloy. The more homogeneous the size of γ＇ precipitate, the longer the rupture life. The coarsening and rafting behaviors of γ＇ precipitates are observed in DZ24 alloy after the stress-rupture test.

Pattern of liver injury in adult patients with COVID-19: a retrospective analysis of 105 patients

Background: Recent studies reported that patients with coronavirus disease-2019(COVID-19) might have liver injury. However, few data on the combined analysis and change patterns of alanine aminotransferase(ALT), aspartate aminotransferase(AST) and total bilirubin(TBil) have been shown.Methods: This is a single-center retrospective study. A total of 105 adult patients hospitalized for confirmed COVID-19 in Beijing Ditan Hospital between January 12, and March 17, 2020 were included, and divided into mild group(n=79) and severe group(n=26). We compared liver functional test results between the two groups. Category of ALT change during the disease course was also examined.Results: 56.2%(59/105) of the patients had unnormal ALT, AST, or total TBil throughout the course of the disease, but in 91.4%(96/105) cases the level of ALT, AST or TBil ≤3 fold of the upper limit of normal reference range(ULN). The overall distribution of ALT, AST, and TBil were all significantly difference between mild and severe group(P<0.05). The percentage of the patients with elevated both ALT and AST was 12.7%(10/79) in mild cases vs. 46.2%(12/26) in severe cases(P=0.001). 34.6%(9/26) severe group patients started to have abnormal ALT after admission, and 73.3%(77/105) of all patients had normal ALT before discharge.Conclusions: Elevated liver function index is very common in patients with COVID-19 infection, and the level were less than 3×ULN, but most are reversible. The abnormality of 2 or more indexes is low in the patients with COVID-19, but it is more likely to occur in the severe group.

Influence of Annealing Treatments on Microstructure and Mechanical Properties of an Extruded Mg AZ31/Al 7050 Laminate

Mg AZ31/A1 7050 laminate was fabricated by co-extrusion directly from the as-cast Mg AZ31 and Al 7050 billets. The influence of annealing temperature and annealing time on microstructure and mechanical behavior of the extruded Mg/Al laminate was systematically studied. Results show that annealing treatments at 250 ℃ for 3 h or at 350 ℃ for 3 h do not result in an obvious grain coarsening of Mg layer and cannot remove the heterogeneous structure. Annealing does not vary texture in the Mg layer, a large fraction of <0002>//ND and a small fraction of <0002>//TD, but the intensity of component <0002>//ND weakens to some extent. Lamellar microstructure in the A1 layer remains after annealing at250 ℃ for 3 h or at 350 ℃ for 3 h. High fractions of the texture components S and cube exist in the extruded sample, and annealing treatment hardly changes their fractions. Post-annealing treatment will largely reduce yield strength of extruded plate and increase plasticity slightly. The yield strength drops from 302 MPa to 206 MPa after annealing at 250 ℃ for 3 h and to 141 MPa after annealing at 350 ℃ for 3 h. The elongation to fracture increases from 1.5% to 5.4% after annealing at 250 ℃ for 3 h and to 4.8% at 350 ℃ for 3 h. The corresponding mechanism was discussed.

Lewis Acid Enables Ketone Phosphorylation:Synthesis of Alkenyl Phosphonates

Main observation and conclusion An efficient Lewis acid enabled ketones phosphonylation to synthesize vinylphosphonates has been developed.This method relays on ketone hydrophosphonylation/α-hydroxy phosphonates unimolecular elimination(E1)dehydration cascade reaction sequence.

Ratiometric and selective two-photon fluorescent probe based on PET-ICT for imaging Zn^(2+)in living cells and tissues

A two-photon fluorescent probe TPZn was developed for specific ratiometric imaging Zn2＋ in living cells and tissues. Significant ratiometric fluorescence change was based on photoinduced electron transfer and intramolecular charge transfer. The synthetic method of TPZn was simple. It was successfully used to selectively image Zn2＋ based on the higher binding affinity for Zn2＋ than for Cd2＋. TPZn was easily loaded into the living cell and tissues with high membrane permeability in a complex biological environment. TPZn could clearly visualize endogenous Zn2＋ by TP ratiometric imaging in hippocampal slices at a depth of 120 μm. Thus, TPZn is a useful tool to image of Zn2＋ in living cells and tissues without interference from Cd2＋.