Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat exchangers.Several studies are based on inserting fi...Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat exchangers.Several studies are based on inserting fillers inside the tubes to enhance heat transfer.This investigation considered the effects of twisted tapes with large holes on a tubular heat exchanger’s(HX)heat transmission,pressure drop,and thermal boosting factor.In the experimental section,counter-swirl flow generators used twisted tapes with pairs of 1.0 cm-diameter holes and changes in porosity(Rp)at 1.30%and 2.70%.In the experiments,air was utilized as a working fluid in a tube with a circular cross-section.The turbulent flow was considered,with Reynolds numbers(Re)domain from 4800 to 9500,and a boundary condition with a uniform wall heat flux was constructed.The findings expound that when the number of holes rose,the Nusselt number(Nu),the factor of friction(f),and the thermal enhancement factor(η)all increased as well.Additionally,as the friction factor increased,the Nusselt number of the tape-equipped tube was noticeably higher.Additionally,it was discovered that the friction factor was between 70%and 94%lower than the values of the tube without tape,while the(Nu)was between 87%and 97%higher than the conventional tube values.The maximum value ofηis 89%.According to the experimental results,empirical correlations for Nu,f,andηwere also generated.展开更多
BACKGROUND Long-term chemotherapy for patients with gastric cancer(GC),facilitated by peripherally inserted central catheter(PICC)catheterization,reduces vascular damage and enhances drug delivery efficiency but carri...BACKGROUND Long-term chemotherapy for patients with gastric cancer(GC),facilitated by peripherally inserted central catheter(PICC)catheterization,reduces vascular damage and enhances drug delivery efficiency but carries risks of catheter-related complications.A combination of group psychological nursing and physical mo-vement care significantly mitigates the risk of venous thrombosis and improves psychological well-being,and enhances motor function,underscoring its clinical importance.AIM To assess group psychological and physical movement nursing in preventing venous thrombosis in patients with PICC GC.METHODS Sixty-five GC patients with PICC,admitted from January 2022 to January 2023,were randomly divided into two groups using the lottery method:A control group(n=35,routine nursing)and an observation group(n=30,routine nursing plus psychological nursing and physical movement nursing).Both groups re-ceived continuous care for 2 weeks.Pre-nursing and post-nursing data on psycho-logical state,physical function,chemotherapy-related thrombosis incidence,and cancer-related fatigue were analyzed using SPSS 26.0 and GraphPad Prism 8.0.RESULTS After nursing,both groups showed reduced Hamilton Anxiety Scale scores and increased General Perceived Self-Efficacy Scale scores,with the observation group performing better(P<0.05).The Functional Comprehensive Assessment score for the observation group after nursing was(65.42±2.35)points,lower than the control group’s(62.19±4.33)points(P<0.05).Although no significant difference was observed in the incidence of venous thrombosis between the two groups(χ2=0.815,P=0.367),the observation group had lower incidence.Both groups showed decreased Revised Piper Fatigue Scale scores,with the observation group scoring lower(P<0.05).CONCLUSION Group psychological and physical movement nursing for patients with PICC reduces venous thrombosis risk,improves psychological well-being,cancer-related fatigue,and physical function,making it highly promotable.展开更多
An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acylox...An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acyloxy esters in moderate to high yields with a broad substrate scope.All starting materials are readily available,and the reactions can be conducted in the open air at room temperature.展开更多
A blue light-induced formal insertion reaction ofα-siloxy carbene into the C—H bond of 1,3-diketones has been reported.Under the irradiation of blue light,acylsilane converts toα-siloxy carbene,which then undergoes...A blue light-induced formal insertion reaction ofα-siloxy carbene into the C—H bond of 1,3-diketones has been reported.Under the irradiation of blue light,acylsilane converts toα-siloxy carbene,which then undergoes formal C—H bond insertion reaction with the enol form of 1,3-diketone.This method uses readily available and relative stable acylsilane as car-bene precursor,which features a simple and metal-free approach under mild conditions.Moreover,the synthetic potential of this protocol has been demonstrated by performing the reaction on a gram scale with comparable high yield.展开更多
There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresse...There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresses carrier leakage by inserting n-Ga_(0.55)In_(0.45)P and p-GaAs_(0.6)P_(0.4) between barriers and waveguide layers,respectively,to modulate the energy band structure and to increase the height of barrier.The results show that the leakage current density reduces by 87.71%,compared to traditional structure.The nonradiative recombination current density of novel structure reduces to 37.411 A/cm^(2),and the output power reaches 12.80 W with wall-plug efficiency of 78.24%at an injection current density 5 A/cm^(2) at room temperature.In addition,the temperature drift coefficient of center wavelength is 0.206 nm/℃at the temperature range from 5℃to 65℃,and the slope of fitted straight line of threshold current with temperature variation is 0.00113.The novel epitaxial structure provides a theoretical basis for achieving high-power laser diode.展开更多
The ThinKing by Russian watchmaker Konstantin Chaykin is only 1.65 millimeters thick,making it the world's thinnest mechanical wristwatch.The“arms race”for the world's thinnest wristwatch has been in full sw...The ThinKing by Russian watchmaker Konstantin Chaykin is only 1.65 millimeters thick,making it the world's thinnest mechanical wristwatch.The“arms race”for the world's thinnest wristwatch has been in full swing for a few years now,with some of the most prestigious(有声望的)watch brands on Earth trying to one‑up each other with ingenious designs.The latest to claim the coveted title is independent watchmaker Konstantin Chaykin with his ThinKing prototype,a 1.65‑millimeter‑thick masterpiece that is so incredibly thin that it needs a special wristband.The ThinKing's case is so delicate that the simple pressure from being worn is enough to damage it,so the special strap made of alligator leather and elastic(有弹性的)inserts with titanium(钛)has to absorb some of the shocks,twisting and bending.展开更多
The switchable cross-coupling of indoles and pyridotriazoles through carbene insertion at C_(2)-or C_(3)-positon has been developed in this paper.This highly site-selective C-H carbenoid functionalization is determine...The switchable cross-coupling of indoles and pyridotriazoles through carbene insertion at C_(2)-or C_(3)-positon has been developed in this paper.This highly site-selective C-H carbenoid functionalization is determined by both the Rh-catalyst species and auxiliary groups.[Cp∗RhCl_(2)]_(2) and coordinating pyrimidyl group direct the C-H carbenoid functionalization to occur at the C_(2)-position,while Rh2OAc4 and noncoordinating benzyl group lead the reaction to occur at the C_(3)-position of the indoles.This regioselective C−H functionalization strategy is of significant importance for the discovery of indole drugs.展开更多
Achieving high-performance aqueous zinc-ion batteries requires addressing the challenges associated with the stability of zinc metal anodes,particularly the formation of inhomogeneous zinc dendrites during cycling and...Achieving high-performance aqueous zinc-ion batteries requires addressing the challenges associated with the stability of zinc metal anodes,particularly the formation of inhomogeneous zinc dendrites during cycling and unstable surface electrochemistry.This study introduces a practical method for scattering untreated bulk hexagonal boron nitride(h-BN)particles onto the zinc anode surface.During cycling,stabilized zinc fills the interstices of scattered h-BN,resulting in a more favorable(002)orientation.Consequently,zinc dendrite formation is effectively suppressed,leading to improved electrochemical stability.The zinc with scattered h-BN in a symmetric cell configuration maintains stability 10 times longer than the bare zinc symmetric cell,lasting 500 hours.Furthermore,in a full cell configuration withα-MnO_(2) cathode,increased H^(+)ion activity can effectively alter the major redox kinetics of cycling due to the presence of scattered h-BN on the zinc anode.This shift in H^(+)ion activity lowers the overall redox potential,resulting in a discharge capacity retention of 96.1%for 300 cycles at a charge/discharge rate of 0.5 Ag^(-1).This study highlights the crucial role of surface modification,and the innovative use of bulk h-BN provides a practical and effective solution for improving the performance and stability.展开更多
Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on...Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on T7 RNA polymerase.Full-length cDNA of the LN16-A strain was constructed by assembling 5 cDNA fragments between the T7 promoter and hepatitis delta virus ribozyme.Transfection of this plasmid,along with the supporting plasmids encoding the N,P,M2-1,and L proteins of LN16-A into BSR-T7/5 cells,resulted in the recovery of aMPV subtype B.To identify an effective insertion site,the enhanced green fluorescent protein(EGFP)gene was inserted into different sites of the LN16-A genome to generate recombinant LN16-As.The results showed that the expression levels of EGFP at the site between the G and L genes of LN16-A were significantly higher than those at the other two sites(between the leader and N genes or replacing the SH gene).To verify the availability of the site between G and L for foreign gene expression,the VP2 gene of very virulent infectious bursal disease virus(vvIBDV)was inserted into this site,and recombinant LN16-A(rLN16A-vvVP2)was successfully rescued.Single immunization of specificpathogen-free chickens with rLN16A-vvVP2 induced high levels of neutralizing antibodies and provided 100%protection against the virulent aMPV subtype B and vvIBDV.Establishing a reverse genetics system here provides an important foundation for understanding aMPV pathogenesis and developing novel vector vaccines.展开更多
Intelligent production is an important development direction in intelligent manufacturing,with intelligent factories playing a crucial role in promoting intelligent production.Flexible job shops,as the main form of in...Intelligent production is an important development direction in intelligent manufacturing,with intelligent factories playing a crucial role in promoting intelligent production.Flexible job shops,as the main form of intelligent factories,constantly face dynamic disturbances during the production process,including machine failures and urgent orders.This paper discusses the basic models and research methods of job shop scheduling,emphasizing the important role of dynamic job shop scheduling and its response schemes in future research.A multi-objective flexible job shop dynamic scheduling mathematical model is established,highlighting its complex and multi-constraint characteristics under different interferences.A classification discussion is conducted on the dynamic response methods and optimization objectives under machine failures,emergency orders,fuzzy completion times,and mixed dynamic events.The development process of traditional scheduling rules and intelligent methods in dynamic scheduling are also analyzed.Finally,based on the current development status of job shop scheduling and the requirements of intelligent manufacturing,the future development trends of dynamic scheduling in flexible job shops are proposed.展开更多
Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uro...Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uronosyltransferases(UATs)to construct glycans containing uronic acids.Despite their biological importance,the synthesis of naturally occurring NDP-uronic acids on a large scale remains challenging.Here,we developed an oxidation reaction insertion strategy for the efficient synthesis of NDP-uronic acids,and 11 NDP-uronic acids were successfully prepared in good yield and on a large scale.The prepared NDP-uronic acids can be used to explore new uronosyltransferases and synthesize uronic acids containing carbohydrates for fundamental research.展开更多
Genome rearrangement is an important process that leads to genetic diversity,including mutation-related insertions,deletions,or inversions in the genome[1,2].
BACKGROUND Peripherally inserted central catheters(PICCs)are widely used for administering chemotherapy to breast cancer patients due to their long-term indwelling capability,versatility in drug administration,and fle...BACKGROUND Peripherally inserted central catheters(PICCs)are widely used for administering chemotherapy to breast cancer patients due to their long-term indwelling capability,versatility in drug administration,and flexibility.PICCs infection are a relatively common occurrence,yet there were no reported instances that it can metastasise to the lumbar spine.CASE SUMMARY This case report describes a breast cancer patient who developed a methicillinresistant Staphylococcus aureus lumbar vertebral infection secondary to a PICCrelated infection during chemotherapy.Following PICC removal,bacterial culture confirmed the presence of highly virulent methicillin-resistant Staphylococcus aureus.The patient presented with fever and severe lumbar pain.Lumbar magnetic resonance imaging revealed paraspinal muscle edema from L1 to L3 with abnormal signal intensity in the affected regions,suggestive of vertebral osteomyelitis.Prompt initiation of appropriate antibiotic therapy based on the culture results led to significant improvement in the patient’s lumbar pain.CONCLUSION This case highlights the importance of vigilant infection prevention and control measures to minimize the risk of PICC-related complications,such as bloodstream infections and subsequent metastatic infections.展开更多
BACKGROUND Ultrasound-guided peripherally inserted central catheter(PICC)placement is vital for cancer therapy,but lidocaine infiltration faces limitations like puncture pain and vasospasm.AIM To assess the clinical e...BACKGROUND Ultrasound-guided peripherally inserted central catheter(PICC)placement is vital for cancer therapy,but lidocaine infiltration faces limitations like puncture pain and vasospasm.AIM To assess the clinical efficacy of a no-pain intervention-combining compound lidocaine cream with warm compress-in reducing pain during ultrasound-guided PICC placement in cancer patients.METHODS A retrospective cohort study analyzed 88 cancer patients undergoing PICC placement(Shanghai Fourth People’s Hospital,2024).Patients were divided into control(lidocaine infiltration,n=44)and intervention(cream+warm compress,n=44)groups.Primary outcomes:Pain scores(numerical rating scale),procedural time,complications;secondary outcome:Satisfaction.RESULTS The intervention group showed significantly lower pain scores(1.2±0.4 vs 3.8±1.2,P=0.012)with comparable first-attempt success(95.5%vs 90.9%)and safety(P=0.672).Thermal activation of transient receptor potential vanilloid 1 channel enhanced drug penetration,achieving anesthesia within 8-10 minutes.Patient satisfaction reached 97.7%.CONCLUSION The combination of compound lidocaine cream with warm compress significantly alleviates procedural pain and enhances patient satisfaction during ultrasound-guided PICC placement in cancer patients,supporting its clinical application.展开更多
BACKGROUND Difficulty of colonoscopy insertion(DCI)significantly affects colonoscopy effectiveness and serves as a key quality indicator.Predicting and evaluating DCI risk preoperatively is crucial for optimizing intr...BACKGROUND Difficulty of colonoscopy insertion(DCI)significantly affects colonoscopy effectiveness and serves as a key quality indicator.Predicting and evaluating DCI risk preoperatively is crucial for optimizing intraoperative strategies.AIM To evaluate the predictive performance of machine learning(ML)algorithms for DCI by comparing three modeling approaches,identify factors influencing DCI,and develop a preoperative prediction model using ML algorithms to enhance colonoscopy quality and efficiency.METHODS This cross-sectional study enrolled 712 patients who underwent colonoscopy at a tertiary hospital between June 2020 and May 2021.Demographic data,past medical history,medication use,and psychological status were collected.The endoscopist assessed DCI using the visual analogue scale.After univariate screening,predictive models were developed using multivariable logistic regression,least absolute shrinkage and selection operator(LASSO)regression,and random forest(RF)algorithms.Model performance was evaluated based on discrimination,calibration,and decision curve analysis(DCA),and results were visualized using nomograms.RESULTS A total of 712 patients(53.8%male;mean age 54.5 years±12.9 years)were included.Logistic regression analysis identified constipation[odds ratio(OR)=2.254,95%confidence interval(CI):1.289-3.931],abdominal circumference(AC)(77.5–91.9 cm,OR=1.895,95%CI:1.065-3.350;AC≥92 cm,OR=1.271,95%CI:0.730-2.188),and anxiety(OR=1.071,95%CI:1.044-1.100)as predictive factors for DCI,validated by LASSO and RF methods.Model performance revealed training/validation sensitivities of 0.826/0.925,0.924/0.868,and 1.000/0.981;specificities of 0.602/0.511,0.510/0.562,and 0.977/0.526;and corresponding area under the receiver operating characteristic curves(AUCs)of 0.780(0.737-0.823)/0.726(0.654-0.799),0.754(0.710-0.798)/0.723(0.656-0.791),and 1.000(1.000-1.000)/0.754(0.688-0.820),respectively.DCA indicated optimal net benefit within probability thresholds of 0-0.9 and 0.05-0.37.The RF model demonstrated superior diagnostic accuracy,reflected by perfect training sensitivity(1.000)and highest validation AUC(0.754),outperforming other methods in clinical applicability.CONCLUSION The RF-based model exhibited superior predictive accuracy for DCI compared to multivariable logistic and LASSO regression models.This approach supports individualized preoperative optimization,enhancing colonoscopy quality through targeted risk stratification.展开更多
BACKGROUND Central venous access is essential for administering chemotherapy in patients with gastrointestinal cancer.Peripherally inserted central catheters(PICC)and totally implantable venous access ports(TIVAP)are ...BACKGROUND Central venous access is essential for administering chemotherapy in patients with gastrointestinal cancer.Peripherally inserted central catheters(PICC)and totally implantable venous access ports(TIVAP)are widely used,but comparative data regarding their impact on catheter-related complications and quality of life(QoL)remain limited.AIM To evaluate the impact of TIVAPs compared with PICC on catheter-related complications and QoL in patients with gastrointestinal cancer undergoing chemotherapy.METHODS This retrospective study included adults with gastrointestinal cancer who underwent central venous access device insertion for chemotherapy at our institution between December 2021 and December 2024.Inclusion criteria encompassed indications for intermittent intravenous chemotherapy,anticipated treatment duration of≥12 weeks,an adequate preoperative hematologic profile,accessible upper body veins,and complete medical records.Patients were excluded if they had an anticipated survival of less than three months,active systemic infection,severe thrombosis or coagulopathy,communication barriers,or an urgent need for dialysis access.Patients were assigned to either the PICC or TIVAP group based on device type.Data collected included demographic variables,cancer characteristics,insertion procedure details,complications,and QoL,assessed via the EuroQol 5-Dimensions-3 levels,visual analogue scale,and the European Organization for Research and Treatment of Cancer QoL Questionnaire-Core 30.RESULTS A total of 346 patients were analyzed.Baseline demographic,clinical,and cancer characteristics were similar between groups.The TIVAP group demonstrated a significantly lower incidence of catheter-related complications than the PICC group,with no pneumothorax occurring in either group.QoL assessments at baseline were comparable.At one month,the TIVAP group exhibited significantly higher EuroQoL Five Dimensions health state scores and QLQ-C30 global health status scores.Multivariate analysis identified TIVAP use,catheter tip placement in the distal superior vena cava/right atrium,prophylactic antibiotic administration,and antimicrobial dressing application as independent protective factors associated with reduced complications and improved QoL.CONCLUSION In patients with gastrointestinal cancer undergoing chemotherapy,TIVAPs are associated with a lower incidence of catheter-related complications and improved QoL than PICCs.Optimal device selection,precise catheter tip positioning,and effective perioperative management are critical for minimizing complications and enhancing patient-reported outcomes during treatment.展开更多
A wide passband frequency selective surface(FSS)is proposed using a five-layer stacked structure.The proposed structure applies four layers of dielectric plates and five layers of metal patches to provide a passband a...A wide passband frequency selective surface(FSS)is proposed using a five-layer stacked structure.The proposed structure applies four layers of dielectric plates and five layers of metal patches to provide a passband and exhibits more stable frequency responses and lower insertion loss under wide-angle oblique incidence compared with the typical three-layer metal-dielectric structure.According to the simulation results,the proposed FSS can achieve a passband range of 1.7-2.7 GHz with an insertion loss of less than 0.5 d B and a relative bandwidth of 44.1%,and it can preserve stable transmission characteristics with the incident angle ranging from 0°to 45°.展开更多
Li/MnO_(2) primary batteries are widely used in industry for their high specific capacity and safety.However,a deep comprehension of the Li^(+)insertion mechanism and the high self-discharge rate of the batteries is s...Li/MnO_(2) primary batteries are widely used in industry for their high specific capacity and safety.However,a deep comprehension of the Li^(+)insertion mechanism and the high self-discharge rate of the batteries is still needed.Here,the storage mechanism of Li^(+)in the tunnel structure of MnO_(2) as well as the dissolution and migration of Mn-ions were investigated based on multi-scale approaches.The Li/Mn ratio(at%)is determined at about 0.82 when the discharge voltage decreases to 2 V.The limited Li-ions transport rate in the bulk MnO_(2) restrains the reduction reaction,resulting in a low practical specific capacity.Moreover,utilizing spherical aberration-corrected transmission electron microscopy(TEM)coupled with electron energy loss spectroscopy(EELS),the presence of a mixed valence state layer of Mn^(2+)/Mn^(3+)/Mn^(4+)on the surface of the original 20 nm MnO_(2) particles was identified,which could contribute to the initial dissolution of Mn-ions.The battery separator exhibited channels for Mn-ions migration and diffusion and aggregated Mn particles.We put forward the discharge and degradation route in the ways of Mn-ions trajectories,and our findings provide a deep understanding of the high self-discharge rates and the capacity decay of Li-Mn primary batteries.展开更多
Rechargeable aqueous aluminum ion batteries(AIBs)are inspiring researchers’enthusiasm due to the low cost and high theoretical capacity of aluminum.Polyaniline(PANI)materials have the potential for aluminum ion stora...Rechargeable aqueous aluminum ion batteries(AIBs)are inspiring researchers’enthusiasm due to the low cost and high theoretical capacity of aluminum.Polyaniline(PANI)materials have the potential for aluminum ion storage due to the properties of its excellent conductivity and inherent theoretical capacity.However,the poor cycling stability and low loadings of PANI limit its application in energy storage.In this study,PANI-x electrodes with high mass loadings are successfully prepared by the electrodeposition method for reversible AlCl_(2)^(+)storage.Among them,the PANI-2 electrode possesses the highest areal capacity(0.59 and 0.51 mAh cm^(−2)at the current density of 0.5 and 10 mA cm^(−2))and excellent cycling stability in saturated AlCl3.Ex situ N 1s fitting spectra of PANI-2 and molecular dynamics simulations of 1 M,3 M,and saturated AlCl_(3)electrolytes demonstrate that PANI can achieve reversible redox reactions in saturated AlCl3,thereby achieving its excellent stability.Density functional theory calculations and ex situ spectra characterizations of PANI-2 demonstrate the insertion/de-insertion mechanism in the form of AlCl_(2)^(+)ions.In conclusion,PANI-2|Saturated AlCl_(3)|EG(exfoliated graphite foil)full cell is assembled successfully.This work provides promising guidance for the preparation of high-loading electrodes for AIBs.展开更多
Objective:Patients after radical gastrectomy often require medium-to long-term intravenous therapy.However,traditional central venous catheters(CVCs)have issues such as high infection risk and poor comfort.This study ...Objective:Patients after radical gastrectomy often require medium-to long-term intravenous therapy.However,traditional central venous catheters(CVCs)have issues such as high infection risk and poor comfort.This study aims to deeply explore the clinical application value of peripherally inserted central catheters(PICCs)after radical gastrectomy,providing a scientific basis for optimizing intravenous access selection.Methods:Fifty patients requiring catheterization after radical gastrectomy at the Friendship Hospital of Ili Kazak Autonomous Prefecture from December 2022 to May 2024 were selected.Catheterization site selection was based on patients’preferences,dividing them into two groups:the experimental group receiving PICCs and the control group receiving CVCs,with 25 patients in each group.Multi-dimensional comparative analysis was conducted,including catheterization operation time,catheter indwelling time,success rates of first and second catheterizations,and complication rates.Statistical methods such as t-tests and chi-square tests were used for in-depth analysis.Results:Compared to the control group,the experimental group had longer catheterization operations and catheter indwelling times,and a higher success rate of first catheterization(P<0.05).The incidence of catheterization complications in the experimental group was 12.00%,lower than the 40.00%in the control group(P<0.05).Conclusion:Although PICC catheterization after radical gastrectomy has relatively longer catheterization operation and indwelling times,it has a high success rate of first catheterization and a low complication rate,demonstrating high clinical application value and worth promoting in clinical practice.展开更多
文摘Heat augmentation techniques play a vital role in the heating and cooling processes in industries,including solar collectors and many applications that utilize heat exchangers.Several studies are based on inserting fillers inside the tubes to enhance heat transfer.This investigation considered the effects of twisted tapes with large holes on a tubular heat exchanger’s(HX)heat transmission,pressure drop,and thermal boosting factor.In the experimental section,counter-swirl flow generators used twisted tapes with pairs of 1.0 cm-diameter holes and changes in porosity(Rp)at 1.30%and 2.70%.In the experiments,air was utilized as a working fluid in a tube with a circular cross-section.The turbulent flow was considered,with Reynolds numbers(Re)domain from 4800 to 9500,and a boundary condition with a uniform wall heat flux was constructed.The findings expound that when the number of holes rose,the Nusselt number(Nu),the factor of friction(f),and the thermal enhancement factor(η)all increased as well.Additionally,as the friction factor increased,the Nusselt number of the tape-equipped tube was noticeably higher.Additionally,it was discovered that the friction factor was between 70%and 94%lower than the values of the tube without tape,while the(Nu)was between 87%and 97%higher than the conventional tube values.The maximum value ofηis 89%.According to the experimental results,empirical correlations for Nu,f,andηwere also generated.
文摘BACKGROUND Long-term chemotherapy for patients with gastric cancer(GC),facilitated by peripherally inserted central catheter(PICC)catheterization,reduces vascular damage and enhances drug delivery efficiency but carries risks of catheter-related complications.A combination of group psychological nursing and physical mo-vement care significantly mitigates the risk of venous thrombosis and improves psychological well-being,and enhances motor function,underscoring its clinical importance.AIM To assess group psychological and physical movement nursing in preventing venous thrombosis in patients with PICC GC.METHODS Sixty-five GC patients with PICC,admitted from January 2022 to January 2023,were randomly divided into two groups using the lottery method:A control group(n=35,routine nursing)and an observation group(n=30,routine nursing plus psychological nursing and physical movement nursing).Both groups re-ceived continuous care for 2 weeks.Pre-nursing and post-nursing data on psycho-logical state,physical function,chemotherapy-related thrombosis incidence,and cancer-related fatigue were analyzed using SPSS 26.0 and GraphPad Prism 8.0.RESULTS After nursing,both groups showed reduced Hamilton Anxiety Scale scores and increased General Perceived Self-Efficacy Scale scores,with the observation group performing better(P<0.05).The Functional Comprehensive Assessment score for the observation group after nursing was(65.42±2.35)points,lower than the control group’s(62.19±4.33)points(P<0.05).Although no significant difference was observed in the incidence of venous thrombosis between the two groups(χ2=0.815,P=0.367),the observation group had lower incidence.Both groups showed decreased Revised Piper Fatigue Scale scores,with the observation group scoring lower(P<0.05).CONCLUSION Group psychological and physical movement nursing for patients with PICC reduces venous thrombosis risk,improves psychological well-being,cancer-related fatigue,and physical function,making it highly promotable.
文摘An efficient TfOH-catalyzed O—H insertion reaction of α-aryl diazoesters with carboxylic acids is reported.This metal-free protocol provides an operationally simple method for a one-pot assembly of diverse α-acyloxy esters in moderate to high yields with a broad substrate scope.All starting materials are readily available,and the reactions can be conducted in the open air at room temperature.
文摘A blue light-induced formal insertion reaction ofα-siloxy carbene into the C—H bond of 1,3-diketones has been reported.Under the irradiation of blue light,acylsilane converts toα-siloxy carbene,which then undergoes formal C—H bond insertion reaction with the enol form of 1,3-diketone.This method uses readily available and relative stable acylsilane as car-bene precursor,which features a simple and metal-free approach under mild conditions.Moreover,the synthetic potential of this protocol has been demonstrated by performing the reaction on a gram scale with comparable high yield.
文摘There is nonradiative recombination in waveguide region owing to severe carrier leakage,which in turn reduces output power and wall-plug efficiency.In this paper,we designed a novel epitaxial structure,which suppresses carrier leakage by inserting n-Ga_(0.55)In_(0.45)P and p-GaAs_(0.6)P_(0.4) between barriers and waveguide layers,respectively,to modulate the energy band structure and to increase the height of barrier.The results show that the leakage current density reduces by 87.71%,compared to traditional structure.The nonradiative recombination current density of novel structure reduces to 37.411 A/cm^(2),and the output power reaches 12.80 W with wall-plug efficiency of 78.24%at an injection current density 5 A/cm^(2) at room temperature.In addition,the temperature drift coefficient of center wavelength is 0.206 nm/℃at the temperature range from 5℃to 65℃,and the slope of fitted straight line of threshold current with temperature variation is 0.00113.The novel epitaxial structure provides a theoretical basis for achieving high-power laser diode.
文摘The ThinKing by Russian watchmaker Konstantin Chaykin is only 1.65 millimeters thick,making it the world's thinnest mechanical wristwatch.The“arms race”for the world's thinnest wristwatch has been in full swing for a few years now,with some of the most prestigious(有声望的)watch brands on Earth trying to one‑up each other with ingenious designs.The latest to claim the coveted title is independent watchmaker Konstantin Chaykin with his ThinKing prototype,a 1.65‑millimeter‑thick masterpiece that is so incredibly thin that it needs a special wristband.The ThinKing's case is so delicate that the simple pressure from being worn is enough to damage it,so the special strap made of alligator leather and elastic(有弹性的)inserts with titanium(钛)has to absorb some of the shocks,twisting and bending.
基金CAMS Innovation Fund for Medical Sciences(CIFMS)(Nos.2022-I2M-1-013,2022-I2M-1-014,2022-I2M-2-002).
文摘The switchable cross-coupling of indoles and pyridotriazoles through carbene insertion at C_(2)-or C_(3)-positon has been developed in this paper.This highly site-selective C-H carbenoid functionalization is determined by both the Rh-catalyst species and auxiliary groups.[Cp∗RhCl_(2)]_(2) and coordinating pyrimidyl group direct the C-H carbenoid functionalization to occur at the C_(2)-position,while Rh2OAc4 and noncoordinating benzyl group lead the reaction to occur at the C_(3)-position of the indoles.This regioselective C−H functionalization strategy is of significant importance for the discovery of indole drugs.
基金supported by the Korean Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea Government(MOTIE)(RS-2023-00303581,Multiscale Simulation-Driven Development of Cost-Effective and Stable Aqueous Zn Ion Battery with Energy Density of 110 Wh/L for Energy Storage Systems:A Korea-USA Collaboration)。
文摘Achieving high-performance aqueous zinc-ion batteries requires addressing the challenges associated with the stability of zinc metal anodes,particularly the formation of inhomogeneous zinc dendrites during cycling and unstable surface electrochemistry.This study introduces a practical method for scattering untreated bulk hexagonal boron nitride(h-BN)particles onto the zinc anode surface.During cycling,stabilized zinc fills the interstices of scattered h-BN,resulting in a more favorable(002)orientation.Consequently,zinc dendrite formation is effectively suppressed,leading to improved electrochemical stability.The zinc with scattered h-BN in a symmetric cell configuration maintains stability 10 times longer than the bare zinc symmetric cell,lasting 500 hours.Furthermore,in a full cell configuration withα-MnO_(2) cathode,increased H^(+)ion activity can effectively alter the major redox kinetics of cycling due to the presence of scattered h-BN on the zinc anode.This shift in H^(+)ion activity lowers the overall redox potential,resulting in a discharge capacity retention of 96.1%for 300 cycles at a charge/discharge rate of 0.5 Ag^(-1).This study highlights the crucial role of surface modification,and the innovative use of bulk h-BN provides a practical and effective solution for improving the performance and stability.
基金supported by the grants from the National Key Research and Development Program of China(2022YFD1800604)the China Agriculture Research System(CARS-41)the Heilongjiang Touyan Innovation Team Program,China。
文摘Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on T7 RNA polymerase.Full-length cDNA of the LN16-A strain was constructed by assembling 5 cDNA fragments between the T7 promoter and hepatitis delta virus ribozyme.Transfection of this plasmid,along with the supporting plasmids encoding the N,P,M2-1,and L proteins of LN16-A into BSR-T7/5 cells,resulted in the recovery of aMPV subtype B.To identify an effective insertion site,the enhanced green fluorescent protein(EGFP)gene was inserted into different sites of the LN16-A genome to generate recombinant LN16-As.The results showed that the expression levels of EGFP at the site between the G and L genes of LN16-A were significantly higher than those at the other two sites(between the leader and N genes or replacing the SH gene).To verify the availability of the site between G and L for foreign gene expression,the VP2 gene of very virulent infectious bursal disease virus(vvIBDV)was inserted into this site,and recombinant LN16-A(rLN16A-vvVP2)was successfully rescued.Single immunization of specificpathogen-free chickens with rLN16A-vvVP2 induced high levels of neutralizing antibodies and provided 100%protection against the virulent aMPV subtype B and vvIBDV.Establishing a reverse genetics system here provides an important foundation for understanding aMPV pathogenesis and developing novel vector vaccines.
基金supported by the National Key Research and Development Program Project(No.2021YFB3301300).
文摘Intelligent production is an important development direction in intelligent manufacturing,with intelligent factories playing a crucial role in promoting intelligent production.Flexible job shops,as the main form of intelligent factories,constantly face dynamic disturbances during the production process,including machine failures and urgent orders.This paper discusses the basic models and research methods of job shop scheduling,emphasizing the important role of dynamic job shop scheduling and its response schemes in future research.A multi-objective flexible job shop dynamic scheduling mathematical model is established,highlighting its complex and multi-constraint characteristics under different interferences.A classification discussion is conducted on the dynamic response methods and optimization objectives under machine failures,emergency orders,fuzzy completion times,and mixed dynamic events.The development process of traditional scheduling rules and intelligent methods in dynamic scheduling are also analyzed.Finally,based on the current development status of job shop scheduling and the requirements of intelligent manufacturing,the future development trends of dynamic scheduling in flexible job shops are proposed.
基金financially supported by National Natural Science Foundation of China(No.22207113 to J.Zhang)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110588to J.Zhang)Natural Science Foundation of Shanghai Municipality(No.22ZR1474000 to L.Wen)。
文摘Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uronosyltransferases(UATs)to construct glycans containing uronic acids.Despite their biological importance,the synthesis of naturally occurring NDP-uronic acids on a large scale remains challenging.Here,we developed an oxidation reaction insertion strategy for the efficient synthesis of NDP-uronic acids,and 11 NDP-uronic acids were successfully prepared in good yield and on a large scale.The prepared NDP-uronic acids can be used to explore new uronosyltransferases and synthesize uronic acids containing carbohydrates for fundamental research.
基金supported by grants(92168103,32171417,2019CXJQ01)from the National Nature Science Foundation of China,Shanghai Municipal GovernmentPeak Disciplines(Type IV)of Institutions of Higher Learning in Shanghai.
文摘Genome rearrangement is an important process that leads to genetic diversity,including mutation-related insertions,deletions,or inversions in the genome[1,2].
基金Supported by the Shandong Province Medical and Health Technology Development Plan,No.202204011069.
文摘BACKGROUND Peripherally inserted central catheters(PICCs)are widely used for administering chemotherapy to breast cancer patients due to their long-term indwelling capability,versatility in drug administration,and flexibility.PICCs infection are a relatively common occurrence,yet there were no reported instances that it can metastasise to the lumbar spine.CASE SUMMARY This case report describes a breast cancer patient who developed a methicillinresistant Staphylococcus aureus lumbar vertebral infection secondary to a PICCrelated infection during chemotherapy.Following PICC removal,bacterial culture confirmed the presence of highly virulent methicillin-resistant Staphylococcus aureus.The patient presented with fever and severe lumbar pain.Lumbar magnetic resonance imaging revealed paraspinal muscle edema from L1 to L3 with abnormal signal intensity in the affected regions,suggestive of vertebral osteomyelitis.Prompt initiation of appropriate antibiotic therapy based on the culture results led to significant improvement in the patient’s lumbar pain.CONCLUSION This case highlights the importance of vigilant infection prevention and control measures to minimize the risk of PICC-related complications,such as bloodstream infections and subsequent metastatic infections.
基金Supported by the Discipline Promotion Program of Shanghai Fourth People’s Hospital,No.SY-XKZT-2021-2006.
文摘BACKGROUND Ultrasound-guided peripherally inserted central catheter(PICC)placement is vital for cancer therapy,but lidocaine infiltration faces limitations like puncture pain and vasospasm.AIM To assess the clinical efficacy of a no-pain intervention-combining compound lidocaine cream with warm compress-in reducing pain during ultrasound-guided PICC placement in cancer patients.METHODS A retrospective cohort study analyzed 88 cancer patients undergoing PICC placement(Shanghai Fourth People’s Hospital,2024).Patients were divided into control(lidocaine infiltration,n=44)and intervention(cream+warm compress,n=44)groups.Primary outcomes:Pain scores(numerical rating scale),procedural time,complications;secondary outcome:Satisfaction.RESULTS The intervention group showed significantly lower pain scores(1.2±0.4 vs 3.8±1.2,P=0.012)with comparable first-attempt success(95.5%vs 90.9%)and safety(P=0.672).Thermal activation of transient receptor potential vanilloid 1 channel enhanced drug penetration,achieving anesthesia within 8-10 minutes.Patient satisfaction reached 97.7%.CONCLUSION The combination of compound lidocaine cream with warm compress significantly alleviates procedural pain and enhances patient satisfaction during ultrasound-guided PICC placement in cancer patients,supporting its clinical application.
基金the Chinese Clinical Trial Registry(No.ChiCTR2000040109)approved by the Hospital Ethics Committee(No.20210130017).
文摘BACKGROUND Difficulty of colonoscopy insertion(DCI)significantly affects colonoscopy effectiveness and serves as a key quality indicator.Predicting and evaluating DCI risk preoperatively is crucial for optimizing intraoperative strategies.AIM To evaluate the predictive performance of machine learning(ML)algorithms for DCI by comparing three modeling approaches,identify factors influencing DCI,and develop a preoperative prediction model using ML algorithms to enhance colonoscopy quality and efficiency.METHODS This cross-sectional study enrolled 712 patients who underwent colonoscopy at a tertiary hospital between June 2020 and May 2021.Demographic data,past medical history,medication use,and psychological status were collected.The endoscopist assessed DCI using the visual analogue scale.After univariate screening,predictive models were developed using multivariable logistic regression,least absolute shrinkage and selection operator(LASSO)regression,and random forest(RF)algorithms.Model performance was evaluated based on discrimination,calibration,and decision curve analysis(DCA),and results were visualized using nomograms.RESULTS A total of 712 patients(53.8%male;mean age 54.5 years±12.9 years)were included.Logistic regression analysis identified constipation[odds ratio(OR)=2.254,95%confidence interval(CI):1.289-3.931],abdominal circumference(AC)(77.5–91.9 cm,OR=1.895,95%CI:1.065-3.350;AC≥92 cm,OR=1.271,95%CI:0.730-2.188),and anxiety(OR=1.071,95%CI:1.044-1.100)as predictive factors for DCI,validated by LASSO and RF methods.Model performance revealed training/validation sensitivities of 0.826/0.925,0.924/0.868,and 1.000/0.981;specificities of 0.602/0.511,0.510/0.562,and 0.977/0.526;and corresponding area under the receiver operating characteristic curves(AUCs)of 0.780(0.737-0.823)/0.726(0.654-0.799),0.754(0.710-0.798)/0.723(0.656-0.791),and 1.000(1.000-1.000)/0.754(0.688-0.820),respectively.DCA indicated optimal net benefit within probability thresholds of 0-0.9 and 0.05-0.37.The RF model demonstrated superior diagnostic accuracy,reflected by perfect training sensitivity(1.000)and highest validation AUC(0.754),outperforming other methods in clinical applicability.CONCLUSION The RF-based model exhibited superior predictive accuracy for DCI compared to multivariable logistic and LASSO regression models.This approach supports individualized preoperative optimization,enhancing colonoscopy quality through targeted risk stratification.
文摘BACKGROUND Central venous access is essential for administering chemotherapy in patients with gastrointestinal cancer.Peripherally inserted central catheters(PICC)and totally implantable venous access ports(TIVAP)are widely used,but comparative data regarding their impact on catheter-related complications and quality of life(QoL)remain limited.AIM To evaluate the impact of TIVAPs compared with PICC on catheter-related complications and QoL in patients with gastrointestinal cancer undergoing chemotherapy.METHODS This retrospective study included adults with gastrointestinal cancer who underwent central venous access device insertion for chemotherapy at our institution between December 2021 and December 2024.Inclusion criteria encompassed indications for intermittent intravenous chemotherapy,anticipated treatment duration of≥12 weeks,an adequate preoperative hematologic profile,accessible upper body veins,and complete medical records.Patients were excluded if they had an anticipated survival of less than three months,active systemic infection,severe thrombosis or coagulopathy,communication barriers,or an urgent need for dialysis access.Patients were assigned to either the PICC or TIVAP group based on device type.Data collected included demographic variables,cancer characteristics,insertion procedure details,complications,and QoL,assessed via the EuroQol 5-Dimensions-3 levels,visual analogue scale,and the European Organization for Research and Treatment of Cancer QoL Questionnaire-Core 30.RESULTS A total of 346 patients were analyzed.Baseline demographic,clinical,and cancer characteristics were similar between groups.The TIVAP group demonstrated a significantly lower incidence of catheter-related complications than the PICC group,with no pneumothorax occurring in either group.QoL assessments at baseline were comparable.At one month,the TIVAP group exhibited significantly higher EuroQoL Five Dimensions health state scores and QLQ-C30 global health status scores.Multivariate analysis identified TIVAP use,catheter tip placement in the distal superior vena cava/right atrium,prophylactic antibiotic administration,and antimicrobial dressing application as independent protective factors associated with reduced complications and improved QoL.CONCLUSION In patients with gastrointestinal cancer undergoing chemotherapy,TIVAPs are associated with a lower incidence of catheter-related complications and improved QoL than PICCs.Optimal device selection,precise catheter tip positioning,and effective perioperative management are critical for minimizing complications and enhancing patient-reported outcomes during treatment.
基金supported by ZTE Industry-University-Institute Cooperation Funds under Grant No.IA20220800001。
文摘A wide passband frequency selective surface(FSS)is proposed using a five-layer stacked structure.The proposed structure applies four layers of dielectric plates and five layers of metal patches to provide a passband and exhibits more stable frequency responses and lower insertion loss under wide-angle oblique incidence compared with the typical three-layer metal-dielectric structure.According to the simulation results,the proposed FSS can achieve a passband range of 1.7-2.7 GHz with an insertion loss of less than 0.5 d B and a relative bandwidth of 44.1%,and it can preserve stable transmission characteristics with the incident angle ranging from 0°to 45°.
基金supported by the National Natural Science Foundation of China(Nos.U2030206,12104022,52271014 and 22075003)the Presidential Foundation of CAEP(No.YZJJZL2023173)Sichuan Science and Technology Program(No.2021YFH0092).
文摘Li/MnO_(2) primary batteries are widely used in industry for their high specific capacity and safety.However,a deep comprehension of the Li^(+)insertion mechanism and the high self-discharge rate of the batteries is still needed.Here,the storage mechanism of Li^(+)in the tunnel structure of MnO_(2) as well as the dissolution and migration of Mn-ions were investigated based on multi-scale approaches.The Li/Mn ratio(at%)is determined at about 0.82 when the discharge voltage decreases to 2 V.The limited Li-ions transport rate in the bulk MnO_(2) restrains the reduction reaction,resulting in a low practical specific capacity.Moreover,utilizing spherical aberration-corrected transmission electron microscopy(TEM)coupled with electron energy loss spectroscopy(EELS),the presence of a mixed valence state layer of Mn^(2+)/Mn^(3+)/Mn^(4+)on the surface of the original 20 nm MnO_(2) particles was identified,which could contribute to the initial dissolution of Mn-ions.The battery separator exhibited channels for Mn-ions migration and diffusion and aggregated Mn particles.We put forward the discharge and degradation route in the ways of Mn-ions trajectories,and our findings provide a deep understanding of the high self-discharge rates and the capacity decay of Li-Mn primary batteries.
基金supported by the National Natural Science Foundation of China(Grant No.21906015)the Fundamental Research Funds for the Central Universities(Grant No.N2205006 and N2225013).
文摘Rechargeable aqueous aluminum ion batteries(AIBs)are inspiring researchers’enthusiasm due to the low cost and high theoretical capacity of aluminum.Polyaniline(PANI)materials have the potential for aluminum ion storage due to the properties of its excellent conductivity and inherent theoretical capacity.However,the poor cycling stability and low loadings of PANI limit its application in energy storage.In this study,PANI-x electrodes with high mass loadings are successfully prepared by the electrodeposition method for reversible AlCl_(2)^(+)storage.Among them,the PANI-2 electrode possesses the highest areal capacity(0.59 and 0.51 mAh cm^(−2)at the current density of 0.5 and 10 mA cm^(−2))and excellent cycling stability in saturated AlCl3.Ex situ N 1s fitting spectra of PANI-2 and molecular dynamics simulations of 1 M,3 M,and saturated AlCl_(3)electrolytes demonstrate that PANI can achieve reversible redox reactions in saturated AlCl3,thereby achieving its excellent stability.Density functional theory calculations and ex situ spectra characterizations of PANI-2 demonstrate the insertion/de-insertion mechanism in the form of AlCl_(2)^(+)ions.In conclusion,PANI-2|Saturated AlCl_(3)|EG(exfoliated graphite foil)full cell is assembled successfully.This work provides promising guidance for the preparation of high-loading electrodes for AIBs.
基金The Ili Kazakh Autonomous Prefecture Science and Technology Plan Project(Project No.:YJC2023A28)。
文摘Objective:Patients after radical gastrectomy often require medium-to long-term intravenous therapy.However,traditional central venous catheters(CVCs)have issues such as high infection risk and poor comfort.This study aims to deeply explore the clinical application value of peripherally inserted central catheters(PICCs)after radical gastrectomy,providing a scientific basis for optimizing intravenous access selection.Methods:Fifty patients requiring catheterization after radical gastrectomy at the Friendship Hospital of Ili Kazak Autonomous Prefecture from December 2022 to May 2024 were selected.Catheterization site selection was based on patients’preferences,dividing them into two groups:the experimental group receiving PICCs and the control group receiving CVCs,with 25 patients in each group.Multi-dimensional comparative analysis was conducted,including catheterization operation time,catheter indwelling time,success rates of first and second catheterizations,and complication rates.Statistical methods such as t-tests and chi-square tests were used for in-depth analysis.Results:Compared to the control group,the experimental group had longer catheterization operations and catheter indwelling times,and a higher success rate of first catheterization(P<0.05).The incidence of catheterization complications in the experimental group was 12.00%,lower than the 40.00%in the control group(P<0.05).Conclusion:Although PICC catheterization after radical gastrectomy has relatively longer catheterization operation and indwelling times,it has a high success rate of first catheterization and a low complication rate,demonstrating high clinical application value and worth promoting in clinical practice.
