Objective: The aim of our study was to analyze the clinical results and prognosis for early elderly patients after surgery and to explore the rational treatment. Methods: Between January 1992 and December 2008, 98 ear...Objective: The aim of our study was to analyze the clinical results and prognosis for early elderly patients after surgery and to explore the rational treatment. Methods: Between January 1992 and December 2008, 98 early elderly breast cancer patients aged ≥ 65 years were treated with surgery, of which 52 patients received modified radical mastectomy and 46 patients received simple mastectomy. Results: Sixty-four (65.3%) patients had comorbidities including coronary heart disease, hypertension, diabetes, etc. After a median follow up of 56 months (21 to 280 months), the 5-year cumulative survival rate of breast modified radical mastectomy group and mastectomy group were 84.0% and 82.7%, separately (P = 0.653). The 5-year recurrence rate were 3.8% and 8.1%, separately (P = 0.504). Conclusion: The simple mastectomy is suitable for the treatment of early elderly breast cancer patients for its lower complication and recurrence rate. Early old women with breast cancer may be safely treated by simple mastectomy. Our findings suggest that modified radical mastectomy does not significantly increase the overall survival.展开更多
BACKGROUND Modified radical mastectomy(MRM)is the most common surgical treatment for breast cancer.General anesthesia poses a challenge in fragile MRM patients,including cardiovascular instability,insufficient postope...BACKGROUND Modified radical mastectomy(MRM)is the most common surgical treatment for breast cancer.General anesthesia poses a challenge in fragile MRM patients,including cardiovascular instability,insufficient postoperative pain control,nausea and vomiting.Thoracic paravertebral block(TPVB)is adequate for simple mastectomy,but its combination with interscalene brachial plexus block(IBPB)has not yet been proved to be an effective anesthesia method for MRM.CASE SUMMARY We describe our experience of anesthesia and pain management in 10 patients with multiple comorbidities.An ultrasound-guided TPVB was placed at T2-T3 and T5-T6,and combined with IBPB,with administration of 10,15 and 5 mL of 0.5%ropivacaine,respectively.A satisfactory anesthetic effect was proved by the absence of ipsilateral tactile sensation within 30 min.Propofol 3 mg/kg/h and oxygen supplementation via a nasal cannula were administered during surgery.None of the patients required additional narcotics,vasopressors,or conversion to general anesthesia.The maximum pain score was 2 on an 11-point numerical rating scale.Two patients required one dose of celecoxib 8 h postoperatively and none reported nausea or emesis.CONCLUSION This case series demonstrated that combined two-site TPVB and small-volume IBPB with sedation can be used as an alternative anesthetic modality for MRM,providing good postoperative analgesia.展开更多
Objective: To investigate the effects of ultrasound-guided thoracic paravertebral block combined with general anesthesia on the secretion of pain-related mediators after modified radical mastectomy. Methods: A total o...Objective: To investigate the effects of ultrasound-guided thoracic paravertebral block combined with general anesthesia on the secretion of pain-related mediators after modified radical mastectomy. Methods: A total of 108 patients with breast cancer who were treated with modified radical mastectomy in this hospital between July 2015 and February 2017 were divided into the control group (n=54) and paravertebral block group (n=54) by random number table. Control group received routine general anesthesia, and paravertebral block group received ultrasound-guided thoracic paravertebral block combined with general anesthesia. The differences in serum levels of pain mediators, inflammatory factors and stress hormones were compared between the two groups of patients immediately after surgery (T0), 6h after surgery (T1), 12h after surgery (T2) and 24h after surgery (T3). Results: At T0, there was no statistically significant difference in serum levels of pain mediators, inflammatory factors and stress hormones between the two groups. At T1, T2 and T3, serum pain mediators NPY, PGE2 and 5-HT levels of paravertebral block group were lower than those of control group;serum inflammatory factors IL-1, IL-6, TNF-α and MCP-1 levels were lower than those of control group;serum stress hormones ACTH, Cor, AngⅠ and AngⅡ levels were lower than those of control group. Conclusion: ultrasound-guided thoracic paravertebral block combined with general anesthesia can effectively reduce the release of pain mediators and relieve the systemic inflammatory stress response after modified radical mastectomy.展开更多
Objective:To study the clinical effect of breast conserving combined with sentinel lymph node biopsy and modified radical mastectomy in patients with early breast cancer.Methods:Female patients with early breast cance...Objective:To study the clinical effect of breast conserving combined with sentinel lymph node biopsy and modified radical mastectomy in patients with early breast cancer.Methods:Female patients with early breast cancer in clinical stage I and II were selected as the main objects of this study,the study period started from July 2017 to July 2020.In the breast conserving and sentinel lymph node biopsy patients,50 cases were randomly selected as the experimental group;50 cases in the modified radical mastectomy patients were randomly selected as the control group.The clinical intervention effect of the two groups was analyzed.Results:the perioperative indexes of the experimental group were shorter than those of the control group,the patients recovered faster,the incidence of complications in the experimental group was lower,and the quality of life scores of the experimental group were significantly higher than those of the control group,and the difference was statistically significant,the intervention effect of the experimental group was also better.Conclusion:The application of breast conserving and sentinel lymph node biopsy in the treatment of early breast cancer can promote the recovery of patients,shorten the operation time and reduce the rate of complications,which has significant clinical significance.展开更多
Objective:To observe the curative effect of Qingre Shengji Ointment(清热生肌膏)on acute radiation dermatitis caused by radiotherapy after modified radical mastectomy.Methods:100 patients with radiotherapy after modifi...Objective:To observe the curative effect of Qingre Shengji Ointment(清热生肌膏)on acute radiation dermatitis caused by radiotherapy after modified radical mastectomy.Methods:100 patients with radiotherapy after modified radical mastectomy in our hospital from June 2019 to December 2020 were randomly divided into treatment group and control group,with 50 cases in each group.The treatment group was given Qingre Shengji Ointment(清热生肌膏)on the basis of routine nursing,and the intervention began until one week after radiotherapy,while the control group was given routine nursing.Observe and record the occurrence time of acute radiation dermatitis,the degree of acute radiation dermatitis,changes of skin erythema,pruritus,pain,changes of interleukin-6(IL-6)and curative effect were evaluated.The degree of dermatitis was evaluated by RTOG grading standard,the erythema was evaluated by TCM symptom score,and pruritus and pain were evaluated by visual analogue scale(VAS).Blood routine,liver and kidney function,electrocardiogram and other safety indicators and adverse reactions were recorded before and after the study.Results:The time of acute radiation dermatitis was 6-11 days(median 8 days)in the treatment group and 8-14 days(median 10 days)in the control group(P<0.01).The degree and probability of acute radiation dermatitis in the treatment group were 82%(41/50)in grade I,16%(8/50)in grade II and 2%(1/50)in grade III.The degree and probability of acute radiation dermatitis in the control group were 54%(27/50)in grade I,40%(20/50)in grade II and 6%(3/50)in grade III(P<0.05).The highest TCM symptom score of skin erythema in the treatment group was lower than that in the control group(P<0.01).The results of generalized estimation equation show that,The VAS scores of pruritus and pain were(1.34±0.01)and(2.08±0.02)(Waldχ^(2)=1198.123,P<0.01)in the treatment group and(2.08±1.74)(Wald^(2)=1547.804,P<0.01)in the control group,respectively.Compared with the control group,the VAS scores of pruritus and pain were(1.14±0.01)and(2.08±1.74)(Wald^(2)=1547.804,P<0.01)in the treatment group.After observation,the curative effect of the treatment group was better than that of the control group(P<0.05),and the subjective symptoms of patients were obviously improved.After treatment,the level of IL-6 in the treatment group was significantly lower than that before treatment,and was lower than that in the control group(P<0.01).Conclusion:Qingre Shengji Ointment(清热生肌膏)can prevent and treat acute radiation dermatitis to some extent,and its mechanism may be to inhibit the release of inflammatory cytokines,reduce the degree of dermatitis,improve the quality of life of patients,and its safety is good.VAS score can subjectively evaluate the changes of itching and pain,and it is easy to use,so it is worthy of clinical application.展开更多
Background- To compare two types of therapy for primary breast carcinoma, breast-conserving therapy (BCT) and modified radical mastectomy (MRM), in a matched cohort study. Methods: A series of 1,746 patients with...Background- To compare two types of therapy for primary breast carcinoma, breast-conserving therapy (BCT) and modified radical mastectomy (MRM), in a matched cohort study. Methods: A series of 1,746 patients with primary breast cancer treated with BCT or MRM in a single Chinese institute between January 2000 and February 2009 were analyzed retrospectively to compare their outcomes with respect to the incidence of local recurrence (LR), distant metastasis, and survival. The patients were matched with regard to age at diagnosis, spreading to axillary lymph nodes, hormone receptor status, the use of neoadjuvant chemotherapy and maximal tumor diameter. The match ratio was 1:1, and each arm included 873 patients. Results: The median follow-up period was 71 months. The 6-year disease-free survival (DFS) and 6-year distant disease-free survival (DDFS) rates differed significantly between two groups. The 6-year local recurrence-free survival (LRFS) rates were 98.2% [95% confidence interval (CI): 0.973-0.989] in the BCT group and 98.7% (95% CI: 0.980-0.994) in the MRM group (P=0.182), respectively. DFS rates in BCT and MRM groups were 91.3% (95% CI: 0.894-0.932) and 86.3% (95% CI: 0.840-0.886) (P〈0.001), respectively, whereas the DDFS rates in BCT and MRM groups were 93.6% (95% CI: 0.922-0.950) and 87.7% (95% CI: 0.854-0.900) (P〈0.001), respectively. Conclusions: BCT in eligible patients is as effective as MRM with respect to local tumor control, DFS and DDFS, and may result in a better outcome than MRM in Chinese primary breast cancer patients.展开更多
An elastoplastic constitutive model based on the Modified Cam Clay(MCC)model is developed to describe the mechanical behaviour of soils cemented via microbially induced calcite precipitation(MICP).It considers the inc...An elastoplastic constitutive model based on the Modified Cam Clay(MCC)model is developed to describe the mechanical behaviour of soils cemented via microbially induced calcite precipitation(MICP).It considers the increase of the elastic stiffness,the change of the yield surface due to MICP cementation and the degradation of calcium carbonate bonds during shearing.Specifically,to capture the typical contraction-dilation transition in MICP soils,the original volumetric hardening rule in the MCC model is modified to a combined deviatoric and volumetric hardening rule.The model could reproduce a series of drained triaxial tests on MICP-treated soils with different calcium carbonate contents.Further,we carry out a parametric study and observe numerical instability in some cases.In combination with an analytical analysis,our numerical modelling has identified the benefits and limitations of using MCCbased models in the simulation of MICP-cemented soils,leading to suggestions for further model development.展开更多
Spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular factors.Although the spinal cord ...Spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular factors.Although the spinal cord neurons have the capacity to regenerate their axons,the expression of growth inhibitory factors,lack or suppression of proper guidance cues,and profound inflammatory responses do not permit successful regeneration(Khyeam et al.,2021).展开更多
In order to reduce the waste of resources and environmental pollution caused by excessive application of chemical fertilizers, improve the utilization rate of fertilizers, and promote the large-scale and high-quality ...In order to reduce the waste of resources and environmental pollution caused by excessive application of chemical fertilizers, improve the utilization rate of fertilizers, and promote the large-scale and high-quality development of the Chinese rose industry. In this experiment, corn stover biochar, phosphoric acid modified biochar and organic fertilizer were used as test materials, and the effects of mixed application of modified biochar and organic fertilizer on the growth and development of Chinese rose as well as soil physicochemical properties were investigated by using the method of pot planting test. The results showed that modified biochar with organic fertilizer had the most significant effect on the enhancement of soil pH, organic matter content and soil carbon-to-nitrogen ratio. After 120 d of planting, modified biochar with organic fertilizer had the most significant effect on the enhancement of plant height and crown width of Chinese rose;both organic fertilizer and modified biochar with organic fertilizer significantly increased the chlorophyll content of Chinese rose. The number of flowers and the number of branches were the highest in the modified biochar with organic fertilizer treatment. In conclusion, the application of modified biochar with organic fertilizer can better improve the soil pH, and increase the soil organic matter content and carbon-to-nitrogen ratio to change the biological traits of Chinese rose. The results of this study provide a theoretical basis for the reduction of chemical fertilizers and the resource utilization of agricultural wastes and guarantee the sustainable development of the cut flower industry.展开更多
The commercialization of genetically modified(GM)crops has increased food production,improved crop quality,reduced pesticide use,promoted changes in agricultural production methods,and become an important new producti...The commercialization of genetically modified(GM)crops has increased food production,improved crop quality,reduced pesticide use,promoted changes in agricultural production methods,and become an important new production strategy for dealing with insect pests and weeds while reducing the cultivated land area.This article provides a comprehensive examination of the global distribution of GM crops in 2023.It discusses the internal factors that are driving their adoption,such as the increasing number of GM crops and the growing variety of commodities.This article also provides information support and application guidance for the new developments in global agricultural science and technology.展开更多
Under investigation in this paper is a complex modified Korteweg–de Vries(KdV) equation, which describes the propagation of short pulses in optical fibers. Bilinear forms and multi-soliton solutions are obtained thro...Under investigation in this paper is a complex modified Korteweg–de Vries(KdV) equation, which describes the propagation of short pulses in optical fibers. Bilinear forms and multi-soliton solutions are obtained through the Hirota method and symbolic computation. Breather-like and bound-state solitons are constructed in which the signs of the imaginary parts of the complex wave numbers and the initial separations of the two parallel solitons are important factors for the interaction patterns. The periodic structures and position-induced phase shift of some solutions are introduced.展开更多
Granite is usually composed of quartz,biotite,feldspar,and cracks,and the variation characteristics of these components could reflect the deformation and failure process of rock well.Taking granite as an example,the v...Granite is usually composed of quartz,biotite,feldspar,and cracks,and the variation characteristics of these components could reflect the deformation and failure process of rock well.Taking granite as an example,the video camera was used to record the deformation and failure process of rock.The distribution of meso-components in video images was then identified.The meso-components of rock failure precursors were also discussed.Moreover,a modified LSTM(long short-term memory method)based on SSA(sparrow search algorithm)was proposed to estimate the change of meso-components of rock failure precursor.It shows that the initiation and expansion of cracks are mainly caused by feldspar and quartz fracture,and when the quartz and feldspar exit the stress framework,rock failure occurs;the second large increase of crack area and the second large decrease of quartz or feldspar area may be used as a precursor of rock failure;the precursor time of rock failure based on meso-scopic components is about 4 s earlier than that observed by the naked eye;the modified LSTM network has the strongest estimation ability for quartz area change,followed by feldspar and biotite,and has the worst estimation ability for cracks;when using the modified LSTM network to predict the precursors of rock instability and failure,quartz and feldspar could be given priority.The results presented herein may provide reference in the investigation of rock failure mechanism.展开更多
In order to study the anti-fatigue performance of RCA modified asphalt (RMA),the performance of RMA and 90#matrix asphalt with different modifier content were measured by asphalt penetration,ductility,softening point,...In order to study the anti-fatigue performance of RCA modified asphalt (RMA),the performance of RMA and 90#matrix asphalt with different modifier content were measured by asphalt penetration,ductility,softening point,Brookfield viscosity,rheological index,infrared spectrum and dielectric constant test.This paper discusses the changes of asphalt basic indexes,fatigue properties and asphalt components based on dielectric properties under different modifier contents,and analyzes the grey correlation degree between components and asphalt pavement performance indexes.The results show that the optimum content of RCA modifier is 16.7%of the asphalt quality according to the penetration,ductility,softening point,Brockfield viscosity,viscosity temperature curve and fatigue life.In the phase angle-strain curve,there is disorder in the latter part of the curve.According to the strain (ε_(d)) corresponding to the disorder point,a new fatigue failure criterion is proposed and proved.Based on the new asphalt fatigue failure criterion,the fatigue prediction model of asphalt mixture is improved,and the fatigue life predicted by the improved fatigue model is compared with the fatigue life obtained by four-point bending fatigue test.The results show that the proposed new asphalt fatigue failure criterion is reasonable,and the fatigue life predicted by the improved asphalt mixture fatigue prediction model is accurate.The research method of classifying asphalt components based on dielectric properties is simple and effective,and the components have a high correlation with the road performance of base asphalt and modified asphalt.展开更多
Objective:To evaluate the effectiveness and safety of modified Xiaoyao powder for postpartum depression(PPD)by conducting a systematic review of randomized controlled trials(RCTs).Methods:The Chinese National Knowledg...Objective:To evaluate the effectiveness and safety of modified Xiaoyao powder for postpartum depression(PPD)by conducting a systematic review of randomized controlled trials(RCTs).Methods:The Chinese National Knowledge Infrastructure Databases(CNKI),the Chinese Scientific Journals Database(VIP),Wanfang,Google Scholar,the SinoMed,Embase,Cochrane Library,and PubMed databases were searched from their inception to April 25,2023.The Cochrane Risk of Bias tool was used to assess the quality of the trials.We applied the risk ratio to present dichotomous data and the mean difference to present continuous data.Data with similar characteristics were pooled for meta-analysis and heterogeneity was assessed using I2.Results:This review included 35 trials involving 2848 participants.The quality of the included studies was low(unclear randomization processes and insufficient reporting of blinding).Participants treated with modified Xiaoyao powder plus Western medicine showed lower Hamilton Depression Scale(HAMD)depression score than those who used Western medicine alone(mean difference=-2.15;95%confidence interval:-2.52 to 1.78;P<.00001),and higher effective rate(relative risk=1.19;95%confidence interval:1.15 to 1.24;P<.00001),When comparing modified Xiaoyao alone with Western medicine,the HAMD depression score remained low,however,the efficacy rate was higher in the modified Xiaoyao group.Regarding adverse events,the modified Xiaoyao group reported weight gain,nausea,and diarrhea,but no severe adverse events were reported.Conclusion:Modified Xiaoyao may help relieve depression in PPD when used alone or in combination with Western medicine,with minor side effects.Therefore,future high-quality,large-sample size RCTs are warranted.展开更多
Zirconium-based metal-organic framework UiO-66 was successfully prepared by solvothermal method,and UiO-66 was modified by adding regulators such as formic acid,acetic acid,and hydrochloric acid.The NH_(3)-SCR reactiv...Zirconium-based metal-organic framework UiO-66 was successfully prepared by solvothermal method,and UiO-66 was modified by adding regulators such as formic acid,acetic acid,and hydrochloric acid.The NH_(3)-SCR reactivity of the samples was evaluated by the denitration activity evaluation system,and the UiO-66 and the regulator-modified UiO-66 were characterized by XRD,SEM,BET,FTIR,TG,NH_(3)-TPD,etc.,the effects of regulator types on the structure and properties of UiO-66 were investigated.The experimental results show that,after adding the modifier,the morphology of UiO-66 changes from irregular quadrilateral with serious agglomeration to particles with regular crystal shape and good dispersibility,and the crystal morphology of the catalyst is improved.In addition,after adding the modifier,UiO-66 has a larger specific surface area and stronger surface acidity,which optimizes the catalytic performance of UiO-66.The catalytic performance test results of NH_(3)-SCR show that the low-temperature activity of UiO-66 is poor,and it only shows a certain catalytic activity at higher temperatures.The catalytic activity of UiO-66 was significantly improved after adding the regulator.Among them,the UiO-66-HCl modified with hydrochloric acid had the best catalytic activity,and the denitration rate reached 70%when the denitration temperature was 380℃.展开更多
This paper proposes a modified iterative learning control(MILC)periodical feedback-feedforward algorithm to reduce the vibration of a rotor caused by coupled unbalance and parallel misalignment.The control of the vibr...This paper proposes a modified iterative learning control(MILC)periodical feedback-feedforward algorithm to reduce the vibration of a rotor caused by coupled unbalance and parallel misalignment.The control of the vibration of the rotor is provided by an active magnetic actuator(AMA).The iterative gain of the MILC algorithm here presented has a self-adjustment based on the magnitude of the vibration.Notch filters are adopted to extract the synchronous(1×Ω)and twice rotational frequency(2×Ω)components of the rotor vibration.Both the notch frequency of the filter and the size of feedforward storage used during the experiment have a real-time adaptation to the rotational speed.The method proposed in this work can provide effective suppression of the vibration of the rotor in case of sudden changes or fluctuations of the rotor speed.Simulations and experiments using the MILC algorithm proposed here are carried out and give evidence to the feasibility and robustness of the technique proposed.展开更多
Background: Sudden sensorineural hearing loss(SSNHL) is a prevalent emergency in ear, nose, and throat practice. Previous studies have demonstrated that intratympanic steroid therapy(IST) can serve as a salvage treatm...Background: Sudden sensorineural hearing loss(SSNHL) is a prevalent emergency in ear, nose, and throat practice. Previous studies have demonstrated that intratympanic steroid therapy(IST) can serve as a salvage treatment for SSNHL after the failure of systemic steroid therapy(SST).Objective: This study aimed to analyze the efficacy of modified IST involving the insertion of a tympanic tube and gelfoam as a salvage treatment for patients with SSNHL, and to explore its associated factors.Methods: Totally, 74 patients who were aged 22–81 years with SSNHL were enrolled and allocated to either the control group(n = 25) or the treatment group(n = 49) based on their treatment modalities. All patients received SST lasting for at least 7 days. Subsequently, patients in the treatment group, after SST failure, underwent IST twice a week for 2–6 weeks, while the control group did not. Efficacy was assessed by the improvement in pure tone average at the affected frequency at the beginning and end of IST.Results: Hearing improvement in all patients after IST in the treatment group was 9.71 ± 14.84 dB, with significant improvement at affected frequencies(250-8000 Hz) compared with the control group(P < 0.05). The findings indicated the duration from the onset of SSNHL to the beginning of IST as an independent factor for pure tone average improvement after treatment(P = 0.002), whereas age, duration of SST, and time of IST were not(P > 0.05).Conclusion: The modified IST was demonstrated to be a safe and effective method as a salvage treatment for SSNHL. This study explored the efficacy of a modified IST approach, incorporating the utilization of tympanic tubes and gelfoam as key components. The findings underscore the advantages of gelfoam as a strategic drug carrier placed in the round window niche. By minimizing drug loss, extending action time, and increasing perilymph concentration, gelfoam enhances the therapeutic impact of IST, contributing to improved hearing outcomes in patients with SSNHL.展开更多
BACKGROUND With the increasing incidence of proximal gastric cancer,laparoscopic proximal gastrectomy has been applied.However,reflux esophagitis often occurs after traditional esophagogastric anastomosis.In order to ...BACKGROUND With the increasing incidence of proximal gastric cancer,laparoscopic proximal gastrectomy has been applied.However,reflux esophagitis often occurs after traditional esophagogastric anastomosis.In order to solve this problem,several methods of digestive tract reconstruction have emerged,but the most satisfying method remains to be discussed.Therefore,we modified traditional Kamikawa anastomosis to investigate the appropriate digestive tract reconstruction in laparo-scopic proximal gastrectomy.All the patients were successfully operated on without conversion to laparotomy.The duration of operation and digestive tract reconstruction were 203.500(150-224)min and 87.500(73-111)min,respectively.The intraoperative amount of bleeding was 20.500 mL±0.696 mL.The time of postoperative first flatus,the first postoperative fluid intake,and the postoperative length of stay were 2(1-3)d,4(3-5)d,and 9(8-10)d,respectively.All the patients were followed up for 12-23 months.The body mass index at 6 and 12 months after surgery were 22.577 kg/m2±3.098 kg/m2 and 22.594 kg/m2±3.207 kg/m2,respectively.The nutrition risk screening 2002 score,the patient-generated subjective global assessment score,and the gastroesophageal reflux disease scale score were good at 6 and 12 months after surgery.Reflux esophagitis and anastomotic stenosis were not observed in any of the patients during their 12-month postoperative gastroscopy or upper gastrointestinal tract visits.All the patients exhibited no tumor recurrence or metastasis.CONCLUSION The modified Kamikawa anastomosis is safe and feasible for laparoscopic proximal gastrectomy and has good antireflux effects and nutritional status.展开更多
L-tryptophan is an essential amino acid for human health. Nanofibrillated cellulose (NFC) from marram grass (Ammophila arenaria) extracted from plants harvested in the center of Tunisia was used for the first time for...L-tryptophan is an essential amino acid for human health. Nanofibrillated cellulose (NFC) from marram grass (Ammophila arenaria) extracted from plants harvested in the center of Tunisia was used for the first time for the modification of a glassy carbon electrode (GCE), for the sensitive detection of L-tryptophan (Trp). After spectroscopic and morphological characterization of the extracted NFC, the GC electrode modification was monitored through cyclic voltammetry. The NFC-modified electrode exhibited good analytical performance in detecting Trp with a wide linear range between 7.5 × 10−4 mM and 10−2 mM, a detection limit of 0.2 µM, and a high sensitivity of 140.0 µA∙mM−1. Additionally, the NFC/GCE showed a good reproducibility, good selectivity versus other amino acids, uric acid, ascorbic acid, and good applicability to the detection of Trp in urine samples.展开更多
A novel method was developed to enhance the utilization rate of steel slag(SS).Through treatment of SS with phosphoric acid and aminopropyl triethoxysilane(KH550),we obtained modified SS(MSS),which was used to prepare...A novel method was developed to enhance the utilization rate of steel slag(SS).Through treatment of SS with phosphoric acid and aminopropyl triethoxysilane(KH550),we obtained modified SS(MSS),which was used to prepare MSS/wood-plastic composites(MSS/WPCs)by replacing talcum powder(TP).The composites were fabricated through melting blending and hot pressing.Their mechanical and combustion properties,which comprise heat release,smoke release,and thermal stability,were systematically investigated.MSS can improve the mechanical strength of the composites through grafting reactions between wood powder and thermoplastics.Notably,MSS/WPC#50(16wt%MSS)with an MSS-to-TP mass ratio of 1:1 exhibited optimal comprehensive performance.Compared with those of WPC#0 without MSS,the tensile,flexural,and impact strengths of MSS/WPC#50 were increased by 18.5%,12.8%,and 18.0%,respectively.Moreover,the MSS/WPC#50 sample achieved the highest limited oxygen index of 22.5%,the highest vertical burning rating at the V-1 level,and the lowest horizontal burning rate at 44.2 mm/min.The formation of a dense and stable char layer led to improved thermal stability and a considerable reduction in heat and smoke releases of MSS/WPC#50.However,the partial replacement of TP with MSS slightly compromised the mechanical and flame-retardant properties,possibly due to the weak grafting caused by SS powder agglomeration.These findings suggest the suitability of MSS/WPCs for high-value-added applications as decorative panels indoors or outdoors.展开更多
文摘Objective: The aim of our study was to analyze the clinical results and prognosis for early elderly patients after surgery and to explore the rational treatment. Methods: Between January 1992 and December 2008, 98 early elderly breast cancer patients aged ≥ 65 years were treated with surgery, of which 52 patients received modified radical mastectomy and 46 patients received simple mastectomy. Results: Sixty-four (65.3%) patients had comorbidities including coronary heart disease, hypertension, diabetes, etc. After a median follow up of 56 months (21 to 280 months), the 5-year cumulative survival rate of breast modified radical mastectomy group and mastectomy group were 84.0% and 82.7%, separately (P = 0.653). The 5-year recurrence rate were 3.8% and 8.1%, separately (P = 0.504). Conclusion: The simple mastectomy is suitable for the treatment of early elderly breast cancer patients for its lower complication and recurrence rate. Early old women with breast cancer may be safely treated by simple mastectomy. Our findings suggest that modified radical mastectomy does not significantly increase the overall survival.
文摘BACKGROUND Modified radical mastectomy(MRM)is the most common surgical treatment for breast cancer.General anesthesia poses a challenge in fragile MRM patients,including cardiovascular instability,insufficient postoperative pain control,nausea and vomiting.Thoracic paravertebral block(TPVB)is adequate for simple mastectomy,but its combination with interscalene brachial plexus block(IBPB)has not yet been proved to be an effective anesthesia method for MRM.CASE SUMMARY We describe our experience of anesthesia and pain management in 10 patients with multiple comorbidities.An ultrasound-guided TPVB was placed at T2-T3 and T5-T6,and combined with IBPB,with administration of 10,15 and 5 mL of 0.5%ropivacaine,respectively.A satisfactory anesthetic effect was proved by the absence of ipsilateral tactile sensation within 30 min.Propofol 3 mg/kg/h and oxygen supplementation via a nasal cannula were administered during surgery.None of the patients required additional narcotics,vasopressors,or conversion to general anesthesia.The maximum pain score was 2 on an 11-point numerical rating scale.Two patients required one dose of celecoxib 8 h postoperatively and none reported nausea or emesis.CONCLUSION This case series demonstrated that combined two-site TPVB and small-volume IBPB with sedation can be used as an alternative anesthetic modality for MRM,providing good postoperative analgesia.
文摘Objective: To investigate the effects of ultrasound-guided thoracic paravertebral block combined with general anesthesia on the secretion of pain-related mediators after modified radical mastectomy. Methods: A total of 108 patients with breast cancer who were treated with modified radical mastectomy in this hospital between July 2015 and February 2017 were divided into the control group (n=54) and paravertebral block group (n=54) by random number table. Control group received routine general anesthesia, and paravertebral block group received ultrasound-guided thoracic paravertebral block combined with general anesthesia. The differences in serum levels of pain mediators, inflammatory factors and stress hormones were compared between the two groups of patients immediately after surgery (T0), 6h after surgery (T1), 12h after surgery (T2) and 24h after surgery (T3). Results: At T0, there was no statistically significant difference in serum levels of pain mediators, inflammatory factors and stress hormones between the two groups. At T1, T2 and T3, serum pain mediators NPY, PGE2 and 5-HT levels of paravertebral block group were lower than those of control group;serum inflammatory factors IL-1, IL-6, TNF-α and MCP-1 levels were lower than those of control group;serum stress hormones ACTH, Cor, AngⅠ and AngⅡ levels were lower than those of control group. Conclusion: ultrasound-guided thoracic paravertebral block combined with general anesthesia can effectively reduce the release of pain mediators and relieve the systemic inflammatory stress response after modified radical mastectomy.
文摘Objective:To study the clinical effect of breast conserving combined with sentinel lymph node biopsy and modified radical mastectomy in patients with early breast cancer.Methods:Female patients with early breast cancer in clinical stage I and II were selected as the main objects of this study,the study period started from July 2017 to July 2020.In the breast conserving and sentinel lymph node biopsy patients,50 cases were randomly selected as the experimental group;50 cases in the modified radical mastectomy patients were randomly selected as the control group.The clinical intervention effect of the two groups was analyzed.Results:the perioperative indexes of the experimental group were shorter than those of the control group,the patients recovered faster,the incidence of complications in the experimental group was lower,and the quality of life scores of the experimental group were significantly higher than those of the control group,and the difference was statistically significant,the intervention effect of the experimental group was also better.Conclusion:The application of breast conserving and sentinel lymph node biopsy in the treatment of early breast cancer can promote the recovery of patients,shorten the operation time and reduce the rate of complications,which has significant clinical significance.
基金Traditional Chinese Medicine Research Program of Hebei Provincial Administration of Traditional Chinese Medicine(NO.2020512)。
文摘Objective:To observe the curative effect of Qingre Shengji Ointment(清热生肌膏)on acute radiation dermatitis caused by radiotherapy after modified radical mastectomy.Methods:100 patients with radiotherapy after modified radical mastectomy in our hospital from June 2019 to December 2020 were randomly divided into treatment group and control group,with 50 cases in each group.The treatment group was given Qingre Shengji Ointment(清热生肌膏)on the basis of routine nursing,and the intervention began until one week after radiotherapy,while the control group was given routine nursing.Observe and record the occurrence time of acute radiation dermatitis,the degree of acute radiation dermatitis,changes of skin erythema,pruritus,pain,changes of interleukin-6(IL-6)and curative effect were evaluated.The degree of dermatitis was evaluated by RTOG grading standard,the erythema was evaluated by TCM symptom score,and pruritus and pain were evaluated by visual analogue scale(VAS).Blood routine,liver and kidney function,electrocardiogram and other safety indicators and adverse reactions were recorded before and after the study.Results:The time of acute radiation dermatitis was 6-11 days(median 8 days)in the treatment group and 8-14 days(median 10 days)in the control group(P<0.01).The degree and probability of acute radiation dermatitis in the treatment group were 82%(41/50)in grade I,16%(8/50)in grade II and 2%(1/50)in grade III.The degree and probability of acute radiation dermatitis in the control group were 54%(27/50)in grade I,40%(20/50)in grade II and 6%(3/50)in grade III(P<0.05).The highest TCM symptom score of skin erythema in the treatment group was lower than that in the control group(P<0.01).The results of generalized estimation equation show that,The VAS scores of pruritus and pain were(1.34±0.01)and(2.08±0.02)(Waldχ^(2)=1198.123,P<0.01)in the treatment group and(2.08±1.74)(Wald^(2)=1547.804,P<0.01)in the control group,respectively.Compared with the control group,the VAS scores of pruritus and pain were(1.14±0.01)and(2.08±1.74)(Wald^(2)=1547.804,P<0.01)in the treatment group.After observation,the curative effect of the treatment group was better than that of the control group(P<0.05),and the subjective symptoms of patients were obviously improved.After treatment,the level of IL-6 in the treatment group was significantly lower than that before treatment,and was lower than that in the control group(P<0.01).Conclusion:Qingre Shengji Ointment(清热生肌膏)can prevent and treat acute radiation dermatitis to some extent,and its mechanism may be to inhibit the release of inflammatory cytokines,reduce the degree of dermatitis,improve the quality of life of patients,and its safety is good.VAS score can subjectively evaluate the changes of itching and pain,and it is easy to use,so it is worthy of clinical application.
文摘Background- To compare two types of therapy for primary breast carcinoma, breast-conserving therapy (BCT) and modified radical mastectomy (MRM), in a matched cohort study. Methods: A series of 1,746 patients with primary breast cancer treated with BCT or MRM in a single Chinese institute between January 2000 and February 2009 were analyzed retrospectively to compare their outcomes with respect to the incidence of local recurrence (LR), distant metastasis, and survival. The patients were matched with regard to age at diagnosis, spreading to axillary lymph nodes, hormone receptor status, the use of neoadjuvant chemotherapy and maximal tumor diameter. The match ratio was 1:1, and each arm included 873 patients. Results: The median follow-up period was 71 months. The 6-year disease-free survival (DFS) and 6-year distant disease-free survival (DDFS) rates differed significantly between two groups. The 6-year local recurrence-free survival (LRFS) rates were 98.2% [95% confidence interval (CI): 0.973-0.989] in the BCT group and 98.7% (95% CI: 0.980-0.994) in the MRM group (P=0.182), respectively. DFS rates in BCT and MRM groups were 91.3% (95% CI: 0.894-0.932) and 86.3% (95% CI: 0.840-0.886) (P〈0.001), respectively, whereas the DDFS rates in BCT and MRM groups were 93.6% (95% CI: 0.922-0.950) and 87.7% (95% CI: 0.854-0.900) (P〈0.001), respectively. Conclusions: BCT in eligible patients is as effective as MRM with respect to local tumor control, DFS and DDFS, and may result in a better outcome than MRM in Chinese primary breast cancer patients.
基金funded by the German Research Foundation(DFG)(Grant No.NA 330/20e1).
文摘An elastoplastic constitutive model based on the Modified Cam Clay(MCC)model is developed to describe the mechanical behaviour of soils cemented via microbially induced calcite precipitation(MICP).It considers the increase of the elastic stiffness,the change of the yield surface due to MICP cementation and the degradation of calcium carbonate bonds during shearing.Specifically,to capture the typical contraction-dilation transition in MICP soils,the original volumetric hardening rule in the MCC model is modified to a combined deviatoric and volumetric hardening rule.The model could reproduce a series of drained triaxial tests on MICP-treated soils with different calcium carbonate contents.Further,we carry out a parametric study and observe numerical instability in some cases.In combination with an analytical analysis,our numerical modelling has identified the benefits and limitations of using MCCbased models in the simulation of MICP-cemented soils,leading to suggestions for further model development.
文摘Spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular factors.Although the spinal cord neurons have the capacity to regenerate their axons,the expression of growth inhibitory factors,lack or suppression of proper guidance cues,and profound inflammatory responses do not permit successful regeneration(Khyeam et al.,2021).
文摘In order to reduce the waste of resources and environmental pollution caused by excessive application of chemical fertilizers, improve the utilization rate of fertilizers, and promote the large-scale and high-quality development of the Chinese rose industry. In this experiment, corn stover biochar, phosphoric acid modified biochar and organic fertilizer were used as test materials, and the effects of mixed application of modified biochar and organic fertilizer on the growth and development of Chinese rose as well as soil physicochemical properties were investigated by using the method of pot planting test. The results showed that modified biochar with organic fertilizer had the most significant effect on the enhancement of soil pH, organic matter content and soil carbon-to-nitrogen ratio. After 120 d of planting, modified biochar with organic fertilizer had the most significant effect on the enhancement of plant height and crown width of Chinese rose;both organic fertilizer and modified biochar with organic fertilizer significantly increased the chlorophyll content of Chinese rose. The number of flowers and the number of branches were the highest in the modified biochar with organic fertilizer treatment. In conclusion, the application of modified biochar with organic fertilizer can better improve the soil pH, and increase the soil organic matter content and carbon-to-nitrogen ratio to change the biological traits of Chinese rose. The results of this study provide a theoretical basis for the reduction of chemical fertilizers and the resource utilization of agricultural wastes and guarantee the sustainable development of the cut flower industry.
基金supported by the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences。
文摘The commercialization of genetically modified(GM)crops has increased food production,improved crop quality,reduced pesticide use,promoted changes in agricultural production methods,and become an important new production strategy for dealing with insect pests and weeds while reducing the cultivated land area.This article provides a comprehensive examination of the global distribution of GM crops in 2023.It discusses the internal factors that are driving their adoption,such as the increasing number of GM crops and the growing variety of commodities.This article also provides information support and application guidance for the new developments in global agricultural science and technology.
基金Project supported by the National Natural Science Foundation of China (Grant No. 12161061)the Fundamental Research Funds for the Inner Mongolia University of Finance and Economics (Grant No. NCYWT23036)+2 种基金the Young Innovative and Entrepreneurial Talents of the Inner Mongolia Grassland Talents Project in 2022,Autonomous Region “Five Major Tasks” Research Special Project for the Inner Mongolia University of Finance and Economics in 2024 (Grant No. NCXWD2422)High Quality Research Achievement Cultivation Fund for the Inner Mongolia University of Finance and Economics in 2024 (Grant No. GZCG2426)the Talent Development Fund of Inner Mongolia Autonomous Region, China。
文摘Under investigation in this paper is a complex modified Korteweg–de Vries(KdV) equation, which describes the propagation of short pulses in optical fibers. Bilinear forms and multi-soliton solutions are obtained through the Hirota method and symbolic computation. Breather-like and bound-state solitons are constructed in which the signs of the imaginary parts of the complex wave numbers and the initial separations of the two parallel solitons are important factors for the interaction patterns. The periodic structures and position-induced phase shift of some solutions are introduced.
基金Project(41472254)supported by the National Natural Science Foundation of China。
文摘Granite is usually composed of quartz,biotite,feldspar,and cracks,and the variation characteristics of these components could reflect the deformation and failure process of rock well.Taking granite as an example,the video camera was used to record the deformation and failure process of rock.The distribution of meso-components in video images was then identified.The meso-components of rock failure precursors were also discussed.Moreover,a modified LSTM(long short-term memory method)based on SSA(sparrow search algorithm)was proposed to estimate the change of meso-components of rock failure precursor.It shows that the initiation and expansion of cracks are mainly caused by feldspar and quartz fracture,and when the quartz and feldspar exit the stress framework,rock failure occurs;the second large increase of crack area and the second large decrease of quartz or feldspar area may be used as a precursor of rock failure;the precursor time of rock failure based on meso-scopic components is about 4 s earlier than that observed by the naked eye;the modified LSTM network has the strongest estimation ability for quartz area change,followed by feldspar and biotite,and has the worst estimation ability for cracks;when using the modified LSTM network to predict the precursors of rock instability and failure,quartz and feldspar could be given priority.The results presented herein may provide reference in the investigation of rock failure mechanism.
基金Funded by Natural Science Foundation of Inner Mongolia,China (No. 2019MS05033)。
文摘In order to study the anti-fatigue performance of RCA modified asphalt (RMA),the performance of RMA and 90#matrix asphalt with different modifier content were measured by asphalt penetration,ductility,softening point,Brookfield viscosity,rheological index,infrared spectrum and dielectric constant test.This paper discusses the changes of asphalt basic indexes,fatigue properties and asphalt components based on dielectric properties under different modifier contents,and analyzes the grey correlation degree between components and asphalt pavement performance indexes.The results show that the optimum content of RCA modifier is 16.7%of the asphalt quality according to the penetration,ductility,softening point,Brockfield viscosity,viscosity temperature curve and fatigue life.In the phase angle-strain curve,there is disorder in the latter part of the curve.According to the strain (ε_(d)) corresponding to the disorder point,a new fatigue failure criterion is proposed and proved.Based on the new asphalt fatigue failure criterion,the fatigue prediction model of asphalt mixture is improved,and the fatigue life predicted by the improved fatigue model is compared with the fatigue life obtained by four-point bending fatigue test.The results show that the proposed new asphalt fatigue failure criterion is reasonable,and the fatigue life predicted by the improved asphalt mixture fatigue prediction model is accurate.The research method of classifying asphalt components based on dielectric properties is simple and effective,and the components have a high correlation with the road performance of base asphalt and modified asphalt.
基金supported by the State Administration of Traditional Chinese Medicine High-level Key Discipline Construction Project of Traditional Chinese Medicine-Beijing University of Traditional Chinese Medicine Combined Fundamentals of Chinese and Western Medicine(Pharmacology Discipline,Project No.zyyzdxk-2023256).
文摘Objective:To evaluate the effectiveness and safety of modified Xiaoyao powder for postpartum depression(PPD)by conducting a systematic review of randomized controlled trials(RCTs).Methods:The Chinese National Knowledge Infrastructure Databases(CNKI),the Chinese Scientific Journals Database(VIP),Wanfang,Google Scholar,the SinoMed,Embase,Cochrane Library,and PubMed databases were searched from their inception to April 25,2023.The Cochrane Risk of Bias tool was used to assess the quality of the trials.We applied the risk ratio to present dichotomous data and the mean difference to present continuous data.Data with similar characteristics were pooled for meta-analysis and heterogeneity was assessed using I2.Results:This review included 35 trials involving 2848 participants.The quality of the included studies was low(unclear randomization processes and insufficient reporting of blinding).Participants treated with modified Xiaoyao powder plus Western medicine showed lower Hamilton Depression Scale(HAMD)depression score than those who used Western medicine alone(mean difference=-2.15;95%confidence interval:-2.52 to 1.78;P<.00001),and higher effective rate(relative risk=1.19;95%confidence interval:1.15 to 1.24;P<.00001),When comparing modified Xiaoyao alone with Western medicine,the HAMD depression score remained low,however,the efficacy rate was higher in the modified Xiaoyao group.Regarding adverse events,the modified Xiaoyao group reported weight gain,nausea,and diarrhea,but no severe adverse events were reported.Conclusion:Modified Xiaoyao may help relieve depression in PPD when used alone or in combination with Western medicine,with minor side effects.Therefore,future high-quality,large-sample size RCTs are warranted.
基金Funded by the National Key Research and Development Program of China(No.2016YFC0209302)。
文摘Zirconium-based metal-organic framework UiO-66 was successfully prepared by solvothermal method,and UiO-66 was modified by adding regulators such as formic acid,acetic acid,and hydrochloric acid.The NH_(3)-SCR reactivity of the samples was evaluated by the denitration activity evaluation system,and the UiO-66 and the regulator-modified UiO-66 were characterized by XRD,SEM,BET,FTIR,TG,NH_(3)-TPD,etc.,the effects of regulator types on the structure and properties of UiO-66 were investigated.The experimental results show that,after adding the modifier,the morphology of UiO-66 changes from irregular quadrilateral with serious agglomeration to particles with regular crystal shape and good dispersibility,and the crystal morphology of the catalyst is improved.In addition,after adding the modifier,UiO-66 has a larger specific surface area and stronger surface acidity,which optimizes the catalytic performance of UiO-66.The catalytic performance test results of NH_(3)-SCR show that the low-temperature activity of UiO-66 is poor,and it only shows a certain catalytic activity at higher temperatures.The catalytic activity of UiO-66 was significantly improved after adding the regulator.Among them,the UiO-66-HCl modified with hydrochloric acid had the best catalytic activity,and the denitration rate reached 70%when the denitration temperature was 380℃.
基金Supported by National Natural Science Foundation of China(Grant Nos.51975037,52375075).
文摘This paper proposes a modified iterative learning control(MILC)periodical feedback-feedforward algorithm to reduce the vibration of a rotor caused by coupled unbalance and parallel misalignment.The control of the vibration of the rotor is provided by an active magnetic actuator(AMA).The iterative gain of the MILC algorithm here presented has a self-adjustment based on the magnitude of the vibration.Notch filters are adopted to extract the synchronous(1×Ω)and twice rotational frequency(2×Ω)components of the rotor vibration.Both the notch frequency of the filter and the size of feedforward storage used during the experiment have a real-time adaptation to the rotational speed.The method proposed in this work can provide effective suppression of the vibration of the rotor in case of sudden changes or fluctuations of the rotor speed.Simulations and experiments using the MILC algorithm proposed here are carried out and give evidence to the feasibility and robustness of the technique proposed.
文摘Background: Sudden sensorineural hearing loss(SSNHL) is a prevalent emergency in ear, nose, and throat practice. Previous studies have demonstrated that intratympanic steroid therapy(IST) can serve as a salvage treatment for SSNHL after the failure of systemic steroid therapy(SST).Objective: This study aimed to analyze the efficacy of modified IST involving the insertion of a tympanic tube and gelfoam as a salvage treatment for patients with SSNHL, and to explore its associated factors.Methods: Totally, 74 patients who were aged 22–81 years with SSNHL were enrolled and allocated to either the control group(n = 25) or the treatment group(n = 49) based on their treatment modalities. All patients received SST lasting for at least 7 days. Subsequently, patients in the treatment group, after SST failure, underwent IST twice a week for 2–6 weeks, while the control group did not. Efficacy was assessed by the improvement in pure tone average at the affected frequency at the beginning and end of IST.Results: Hearing improvement in all patients after IST in the treatment group was 9.71 ± 14.84 dB, with significant improvement at affected frequencies(250-8000 Hz) compared with the control group(P < 0.05). The findings indicated the duration from the onset of SSNHL to the beginning of IST as an independent factor for pure tone average improvement after treatment(P = 0.002), whereas age, duration of SST, and time of IST were not(P > 0.05).Conclusion: The modified IST was demonstrated to be a safe and effective method as a salvage treatment for SSNHL. This study explored the efficacy of a modified IST approach, incorporating the utilization of tympanic tubes and gelfoam as key components. The findings underscore the advantages of gelfoam as a strategic drug carrier placed in the round window niche. By minimizing drug loss, extending action time, and increasing perilymph concentration, gelfoam enhances the therapeutic impact of IST, contributing to improved hearing outcomes in patients with SSNHL.
基金Supported by the Fujian Medical University Sailing Fund General Project,No.2022QH1117Key Clinical Specialty Discipline Construction Program of Fujian,Fujian Health Medicine and Politics,No.[2022]884.
文摘BACKGROUND With the increasing incidence of proximal gastric cancer,laparoscopic proximal gastrectomy has been applied.However,reflux esophagitis often occurs after traditional esophagogastric anastomosis.In order to solve this problem,several methods of digestive tract reconstruction have emerged,but the most satisfying method remains to be discussed.Therefore,we modified traditional Kamikawa anastomosis to investigate the appropriate digestive tract reconstruction in laparo-scopic proximal gastrectomy.All the patients were successfully operated on without conversion to laparotomy.The duration of operation and digestive tract reconstruction were 203.500(150-224)min and 87.500(73-111)min,respectively.The intraoperative amount of bleeding was 20.500 mL±0.696 mL.The time of postoperative first flatus,the first postoperative fluid intake,and the postoperative length of stay were 2(1-3)d,4(3-5)d,and 9(8-10)d,respectively.All the patients were followed up for 12-23 months.The body mass index at 6 and 12 months after surgery were 22.577 kg/m2±3.098 kg/m2 and 22.594 kg/m2±3.207 kg/m2,respectively.The nutrition risk screening 2002 score,the patient-generated subjective global assessment score,and the gastroesophageal reflux disease scale score were good at 6 and 12 months after surgery.Reflux esophagitis and anastomotic stenosis were not observed in any of the patients during their 12-month postoperative gastroscopy or upper gastrointestinal tract visits.All the patients exhibited no tumor recurrence or metastasis.CONCLUSION The modified Kamikawa anastomosis is safe and feasible for laparoscopic proximal gastrectomy and has good antireflux effects and nutritional status.
文摘L-tryptophan is an essential amino acid for human health. Nanofibrillated cellulose (NFC) from marram grass (Ammophila arenaria) extracted from plants harvested in the center of Tunisia was used for the first time for the modification of a glassy carbon electrode (GCE), for the sensitive detection of L-tryptophan (Trp). After spectroscopic and morphological characterization of the extracted NFC, the GC electrode modification was monitored through cyclic voltammetry. The NFC-modified electrode exhibited good analytical performance in detecting Trp with a wide linear range between 7.5 × 10−4 mM and 10−2 mM, a detection limit of 0.2 µM, and a high sensitivity of 140.0 µA∙mM−1. Additionally, the NFC/GCE showed a good reproducibility, good selectivity versus other amino acids, uric acid, ascorbic acid, and good applicability to the detection of Trp in urine samples.
基金financially supported from the National Natural Science Foundation of China(No.U23A20605)the University Synergy Innovation Program of Anhui Province,China(No.GXXT-2020-072)+2 种基金Anhui Jieqing Project,China(No.2208085J19)Anhui Graduate Innovation and Entrepreneurship Practice Project,China(No.2022cxcysj090)China Baowu Low Carbon Metallurgy Innovation Foundation(No.BWLCF202202).
文摘A novel method was developed to enhance the utilization rate of steel slag(SS).Through treatment of SS with phosphoric acid and aminopropyl triethoxysilane(KH550),we obtained modified SS(MSS),which was used to prepare MSS/wood-plastic composites(MSS/WPCs)by replacing talcum powder(TP).The composites were fabricated through melting blending and hot pressing.Their mechanical and combustion properties,which comprise heat release,smoke release,and thermal stability,were systematically investigated.MSS can improve the mechanical strength of the composites through grafting reactions between wood powder and thermoplastics.Notably,MSS/WPC#50(16wt%MSS)with an MSS-to-TP mass ratio of 1:1 exhibited optimal comprehensive performance.Compared with those of WPC#0 without MSS,the tensile,flexural,and impact strengths of MSS/WPC#50 were increased by 18.5%,12.8%,and 18.0%,respectively.Moreover,the MSS/WPC#50 sample achieved the highest limited oxygen index of 22.5%,the highest vertical burning rating at the V-1 level,and the lowest horizontal burning rate at 44.2 mm/min.The formation of a dense and stable char layer led to improved thermal stability and a considerable reduction in heat and smoke releases of MSS/WPC#50.However,the partial replacement of TP with MSS slightly compromised the mechanical and flame-retardant properties,possibly due to the weak grafting caused by SS powder agglomeration.These findings suggest the suitability of MSS/WPCs for high-value-added applications as decorative panels indoors or outdoors.