Background: The rate of accidental dural puncture is particularly high during the period of training, especially in novices. The structured epidural teaching model (SETM) includes three standardized video lessons, the...Background: The rate of accidental dural puncture is particularly high during the period of training, especially in novices. The structured epidural teaching model (SETM) includes three standardized video lessons, the construction of a 3D epidural module by trainees and practical training by using an epidural simulator with and without the CompuFlo™ Epidural instrument. In this study we report the retrospective analysis of the accidental dural puncture rate of inexperienced trainees during their 6 months clinical practice rotation in obstetrics before and after the introduction of the SETM in our Institution. Method: We evaluated the incidence of accidental dural puncture before the introduction of the SETM methodology and afterwards by analyzing our departmental database from February 2019 to January 2023. All epidural blocks were executed by trainees who had never previously performed an epidural block and were about to begin their obstetrics rotation. Results: We analyzed 7415 epidurals: 3703 were performed before the introduction of the SETM methodology (control group) and 3712 afterwards (study group). The incidence of accidental dural puncture was 0.37% for the control group and 0.13% for the study group (p<.05). The probability of making an accidental dural puncture was 64% (OR: 0.36) lower for trainees who had the training than for those who did not. Conclusions: After the introduction of the structured teaching method, we observed a significant reduction of accidental dural puncture during the training period. We hope that our observation will encourage a constructive discussion among experts about the need to use standardized and validated tools as a valuable aid in teaching epidural anesthesia.展开更多
BACKGROUND Chronic obstructive pulmonary disease(COPD)is associated with high morbidity and mortality rates worldwide.Older patients have a degenerative cardiopulmonary function,weak compensatory capacity,and poor sur...BACKGROUND Chronic obstructive pulmonary disease(COPD)is associated with high morbidity and mortality rates worldwide.Older patients have a degenerative cardiopulmonary function,weak compensatory capacity,and poor surgical tolerance.Therefore,the mode of anesthesia must be optimized.Remimazolam is a new ultrashort-acting benzodiazepine with a rapid onset of action,rapid metabolism,and mild effects on pulmonary circulation.Remimazolam sedation combined with an epidural block has not been reported in hypertensive older adults with severe COPD and inguinal mass resection.CASE SUMMARY We report the case of a 73-year-old man with hypertension and severe COPD,who underwent resection of an enlarged inguinal mass that he had noticed more than 7 mo before presentation.The patient presented with a“right inguinal mass”and was recommended to undergo an enlarged inguinal mass resection.Surgery was relatively challenging,due to the large mass(13 cm×8 cm×7 cm),hard texture,and poor mobility.Considering the advanced age of the patient,gradeⅢhypertension,and severe COPD,we administered remimazolam combined with an epidural block for anesthesia to ensure perioperative safety and careful consideration.The anesthetic effect was precise;the procedure was performed smoothly without any complications,and the patient was successfully anesthetized.However,anesthetic management in such cases has not yet been reported by previous studies.CONCLUSION Remimazolam sedation combined with an epidural block is safe and effective in older patients with hypertension and severe COPD.展开更多
Introduction: Video examples with task demonstrations by experts, with the expert’s eye movements superimposed on the task, are known as “eye movement modeling examples” (EMME). We performed this study to evaluate ...Introduction: Video examples with task demonstrations by experts, with the expert’s eye movements superimposed on the task, are known as “eye movement modeling examples” (EMME). We performed this study to evaluate if there were improvements in the performance of anesthesia novice trainees when executing the epidural technique after an EMME of epidural block procedure. Methods: We developed an eye movement modeling example (EMME) from eye tracking recordings made by experienced anesthesiologists with more than 20 years of experience. Forty-two PGY3 anesthesia trainees who had never previously performed an epidural block were randomized to receive (study group) or not receive (control group) the EMME video before their institutional training. All the trainees were evaluated every 10 epidural blocks until the end of the rotation period, by an independent, blinded observer using the Global Rating Scale for Epidural Anesthesia (GRS). Results: Trainees who received the EMME training exhibited more respect for the patient’s tissues (P Discussion: This is the first study that has used the EMME for a practical, clinical teaching purpose on real patients and that has used it as an aid in teaching epidural anesthesia. We demonstrated that inexperienced trainees who received the EMME training improved their proficiency at epidural blocks as compared to those who had no EMME training beforehand. Given this result, we welcome further studies to investigate the impact and the role of EMME on clinical teaching in the field of anesthesia.展开更多
<b>Background:</b> Poor postoperative pain control leads to longer postoperative care, longer hospital stay and decreased patient overall satisfaction. <b>Aim:</b> To compare the efficacy and s...<b>Background:</b> Poor postoperative pain control leads to longer postoperative care, longer hospital stay and decreased patient overall satisfaction. <b>Aim:</b> To compare the efficacy and safety of bilateral ultrasound-guided quadratus lumborum block versus lumbar epidural block on the management of postoperative pain following major lower abdominal cancer surgery. <b>Methods:</b> The study was a double-blinded, and randomized study, conducted in South Egypt Cancer Institute, Assiut University, Egypt. It included cancer patients scheduled for major lower abdominal cancer surgery in the period from 2019 to 2020. They were divided into two groups: Group Ι received pre-emptive ultrasound-guided Quadratus Lumborum Block (QLB) with 25 mL of 0.25% bupivacaine on each side of the abdominal wall before induction of General Anesthesia (GA), and Group II received pre-emptive lumbar epidural block with 15 mL of 0.25% bupivacaine before induction of GA. VAS score, and time of the first analgesic request and postoperative total analgesic consumption were evaluated. <b>Results:</b> Sixty patients were included in our study. VAS score at rest was comparable between both studied groups in the first 6 h. At 8 and 10 h, Group II had a significantly higher VAS score at rest (P < 0.001 and 0.026 respectively). Meanwhile, at 12 h, patients in Group I had a significantly higher VAS score (P = 0.026). Mean time of the first request for rescue analgesia was significantly prolonged in Group I (13.27 ± 2.38 hrs.) compared to Group II (10.20 ± 1.42 hrs.) (P < 0.001) respectively, mean total morphine consumption, over the first 24 hours postoperatively, was significantly lower in Group I (5.17 ± 1.32 mg) than in Group II (7.33 ± 1.45 mg) (P < 0.001). A larger number of patients in Group II had nausea at different time points postoperatively than in Group I (P < 0.001), but no significant difference was observed between both studied groups regarding the incidence of vomiting. <b>Limitation:</b> Small sample size and shorter period for postoperative follow-up. <b>Conclusions:</b> Management of postoperative pain following major lower abdominal cancer surgery with US-guided QLB was associated with the reduction in the total analgesic consumption and delayed the first request of analgesia as compared to lumbar epidural block technique.展开更多
Background: Pneumatic arterial tourniquet is a very commonly used technique in limb surgeries to provide bloodless field to facilitate dissection and decrease blood loss. However, arterial tourniquet has many deleteri...Background: Pneumatic arterial tourniquet is a very commonly used technique in limb surgeries to provide bloodless field to facilitate dissection and decrease blood loss. However, arterial tourniquet has many deleterious effects including hemodynamic changes, serum lactate and potassium level changes and tourniquet-induced pain which sometimes can be severe and intolerable. Aim of the study: To evaluate the effect of different regional blocks: femoral-sciatic, spinal and epidural blocks on serum lactate and potassium levels and the degree of arterial tourniquet-induced pain in patients undergoing lower limb orthopedic surgeries. Methods: 60 patients underwent lower limb orthopedic surgery with application of tourniquet for duration not more than 90 minutes. Patients were assigned randomly to one of three groups (20 each) Group I had sciatic-femoral block, Group II: patients had spinal anesthesia and Group III: patients had epidural anesthesia. Intraoperative hemodynamics, changes in serum potassium and lactate levels and tourniquet pain after tourniquet inflation & deflation, were recorded. Results: There was no statistically significant difference among the three groups regarding tourniquet pain after tourniquet inflation (p = 0.872) and deflation (p = 0.902), and regarding serum levels changes of potassium (p = 0.067) and lactate (p = 0.051). However, each group showed statistically significant increase in post deflation tourniquet pain (p = 0.003, 0.002, 0.003, in groups F, S, E respectively) and serum potassium (p = 0.004, 0.006, 0.000, in groups F, S, E respectively) and lactate levels (p = 0.004, 0.000, 0.000, in groups F, S, E respectively) when compared to the pre-deflation values, and the increase was directly proportional to the duration of tourniquet. Conclusion: the three different types of anesthesia (femoral-sciatic, spinal and epidural block) have the same effect on serum lactate and potassium levels and the degree of tourniquet pain, which were related to the duration of tourniquet inflation.展开更多
Objective: To investigate the effect of epidural block combined with intravenous anesthesia on stress response and T lymphocyte subsets in patients with breast cancer undergoing radical mastectomy. Methods: In our hos...Objective: To investigate the effect of epidural block combined with intravenous anesthesia on stress response and T lymphocyte subsets in patients with breast cancer undergoing radical mastectomy. Methods: In our hospital from July 2016 to June 2017 undergoing radical mastectomy for breast cancer of 88 patients were randomly divided into observation group and control group of 44 cases, 2 patients underwent routine preoperative preparation, and routine blood pressure, heart rate, pulse, oxygen saturation, ECG monitoring, control group with intravenous anesthesia. The observation group was treated with epidural block combined with intravenous anesthesia. 2 groups of patients before anesthesia, 30 MIM (T0), 1 h after skin incision (T1), 4 h after operation (T2), 24 h after operation (T3), 48 h after operation (T4) from peripheral venous blood were measured by interleukin-8 (IL-8) and interferon gamma (IFN-γ), cortisol (Cor), prolactin (PRL), growth hormone (GH) and T lymphocyte subsets (CD3+, CD4+, CD8+), the calculation of CD4+/CD8+ value. Results: the serum IL-8 level of T1, T2, T3and T4 decreased gradually, were lower than at T0, and the control group at each time point had no significant difference, T1, T2, T3group, T4IL-8 levels lower than the control group;the 2 groups of serum IFN-γ levels T1 and T2had no significant change, T3and T4increased gradually, was higher than that of T0, but no significant difference between the 2 groups of IFN-γ levels. 2 serum Cor levels peaked at T1, decreased at T2, was higher than that of T0, T3, T4returned to T0, the observation group T1, T2Cor level lower than the control group;the serum PRL levels of 2 groups reached a peak at T1, T2, T3at the time of T4decreased gradually, was higher than that of T0, T1, T2, T3of the observation group at the PRL level is lower than the control group;the serum level of GH 2 in group T1increased gradually, reached a peak at T2, T3and T4 decreased gradually, was higher than that of T0, the observation group T1, T2, T3, T4, GH levels lower than the control group. 2 groups of CD3+ decreased gradually in T1, T2, were lower than T0, T3, T4returned to T0, the observation group T1, T2CD3+ was higher than the control group;group CD4+ decreased gradually in T1, T2, T3and T4were lower than control, T0when, and the observation group CD4+ in T1, T2, T3, T4, no significant changes were observed in group T1, T2, T3, T4and CD4+ higher than that of the control group;the 2 group CD8+ had no obvious changes in T1, T2, T3, T4;observation group CD4+/CD8+ decreased gradually in T1, T2, were lower than T0, T3, T4returned to T0, the observation group T1, T2CD4+/CD8+ was higher than the control group. Conclusion: epidural block combined with intravenous anesthesia for breast cancer radical mastectomy can effectively relieve the stress and inflammatory reaction, alleviate the immunosuppression, and help to restore the postoperative immune function.展开更多
Background: The study was done to assess the postoperative analgesic efficacy of ultrasound-guided continuous transverses abdominis plane block, continuous lumbar paravertebral block and a continuous lumbar epidural b...Background: The study was done to assess the postoperative analgesic efficacy of ultrasound-guided continuous transverses abdominis plane block, continuous lumbar paravertebral block and a continuous lumbar epidural block in patients undergoing lower abdominal surgeries (unilateral inguinal hernia repair). We compared their analgesic efficacy over the first 48 hour postoperative, in a randomized, single-blind study in 120 patients divided into four equal groups, 30 patients in each group. Methods: 120 patients randomly assigned into four equal groups, with 30 patients in each group. Group T received ultrasound-guided transverses abdominis plane block with 20 ml of bupivacaine 0.25% followed by continuous infusion of bupivacaine 0.125% (0.1 ml/kg/hr) and group P received ultrasound-guided continuous lumbar paravertebral block with bupivacaine 0.25% bolus dose 20 ml, followed by continuous infusion of bupivacaine 0.125% (0.1 ml/kg/hr). Group E received continuous lumbar epidural infusion of bupivacaine 0.25% bolus dose 20 ml, followed by continuous infusion of bupivacaine 0.125% (0.1 ml/kg/hr) and group C received normal saline bolus dose 20 ml, followed by continuous infusion of normal saline (0.1 ml/kg/hr). General anesthesia induced with fentanyl 1 - 2 μg/kg and propofol 1 - 3 mg/kg followed by atracurium 0.5 mg/kg. At the end of the surgical procedure, we activated the regional block with recording of parameters in the postoperative period each patient was assessed for visual analog scale (VAS) at rest and on movement, analgesic consumption, vital signs and presence of complications (nausea, vomiting, sedation), and postoperative patient satisfaction all data collected postoperatively by a blinded investigator at one, two, 6, 12, 24 and 48 hours postoperatively. Results: Postoperative analgesic efficacy is more in group E than group P and group T, the latter is least effective in pain control. Also in group E the postoperative analgesic consumption is lower than in group P and group T, re-garding complications as nausea and vomiting more recorded in epidural than the other two groups. Conclusion: Regarding postoperative analgesic efficacy, the continuous lumbar epidural block is more effective than continuous paravertebral and continuous transverses abdominis plane block, but regarding complications, there was a higher incidence in epidural group than other two groups.展开更多
BACKGROUND Symptomatic cervical facet cysts are relatively rare compared to those in the lumbar region.These cysts are usually located in the 7th cervical and 1st thoracic vertebral(C7/T1)area,and surgical excision is...BACKGROUND Symptomatic cervical facet cysts are relatively rare compared to those in the lumbar region.These cysts are usually located in the 7th cervical and 1st thoracic vertebral(C7/T1)area,and surgical excision is performed in most cases.However,facet cysts are associated with degenerative conditions,and elderly patients are often ineligible for surgical procedures.Cervical interlaminar epidural block has been used in patients with cervical radiating symptoms and achieved good results.Therefore,cervical interlaminar epidural block may be the first-choice treatment for symptomatic cervical facet cysts.CASE SUMMARY A 70-year-old man complained of a tingling sensation in the left hand,focused on the 4th and 5th fingers,for 1 year,and posterior neck pain for over 5 mo.The patient’s numeric rating scale(NRS)score was 5/10.The patient was diagnosed with symptomatic cervical facet cyst at the left C7/T1 facet joint.Fluoroscopyguided cervical interlaminar epidural block at the C7/T1 level with 20 mg triamcinolone and 5 mL of 0.5%lidocaine was administered.The patient's symptoms improved immediately after the block,with an NRS score of 3 points.After 3 mo,his left posterior neck pain and tingling along the left 8th cervical dermatome were relieved,with an NRS score of 2.CONCLUSION A cervical interlaminar epidural block is a good alternative for managing symptomatic cervical facet cysts.展开更多
BACKGROUND The background of this study was analgesia in natural delivery.The combined spinal-epidural anesthesia has obvious analgesic effect on the parturients in natural labor,and combined spinal-epidural anesthesi...BACKGROUND The background of this study was analgesia in natural delivery.The combined spinal-epidural anesthesia has obvious analgesic effect on the parturients in natural labor,and combined spinal-epidural anesthesia has been widely used in anesthesia for various diseases.AIM To study the effects of combined spinal-epidural anesthesia on anxiety,labor analgesia,and motor blocks in parturients during natural delivery.METHODS A total of 120 women who gave birth at Changning District Maternal and Child Health Hospital between December 2021 to December 2022 were included;a random number table approach was employed to divide the women into a control group and a joint group,with each group consisting of 60 women.The control group was given epidural anesthesia,while the joint group was given combined spinal-epidural anesthesia.The visual analog scale(VAS)was used to evaluate the degree of maternal pain.Comparisons were made between the two groups’conditions of childbirth and the duration of labor.Apgar scores were used to evaluate the status of the newborns at birth;Self-rating Anxiety Scale(SAS)and General Self-Efficacy Scale(GSES)scores,umbilical artery blood gas analysis indices and stress indices were compared between the two groups;and the frequencies of motor block and postpartum complications were analyzed.RESULTS In comparison to the control group,in the joint group,the VAS scores for the first,second,and third stages of labor were lower(P<0.05).The rates of conversion to cesarean section and postpartum blood loss in the joint group were lower than those in the control group(P<0.05).No significant differences were observed in the Apgar score,the duration of the first stage of labor,or the total duration of labor between the two groups(P>0.05).The second and third stages of labor in the joint group were shorter than those in the control group(P<0.05).When compared to the control group,the postpartum SAS score of the joint group was lower,while the GSES score was greater(P<0.05).Between the control group and the joint group,the differences observed in pH,arterial carbon dioxide partial pressure,arterial oxygen partial pressure,or arterial hydrogen ion concentration were not significant(P>0.05).Nitric oxide,cortisol,and adrenaline levels were lower in the joint group than in the control group(P<0.05).There were no substantial differences in Bromage grade or rate of complications between the two groups(P>0.05).CONCLUSION For parturients during natural delivery,combined spinal-epidural anesthesia can reduce anxiety,provide labor analgesia,shorten labor time,and reduce postoperative stress levels but did not result in a motor block.展开更多
Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry worldwide.PRV glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ELISA...Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry worldwide.PRV glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ELISA)has been used to distinguish gE-deleted vaccine-immunized pigs from wild-type virus-infected pigs to eradicate PR in some countries.Nanobody has the advantages of small size and easy genetic engineering and has been a promising diagnostic reagent.However,there were few reports about developing nanobody-based ELISA for detecting anti-PRV-gE antibodies.In the present study,the recombinant PRV-gE was expressed with a bacterial system and used to immunize the Bactrian camel.Then,two nanobodies against PRV-gE were screened from the immunized camel by phage display technique.Subsequently,two nanobody-HRP fusion proteins were expressed with HEK293T cells.The PRV-gE-Nb36-HRP fusion protein was selected as the probe for developing the blocking ELISA(bELISA)to detect anti-PRV-gE antibodies.Through optimizing the conditions of bELISA,the amount of coated antigen was 200 ng per well,and dilutions of the fusion protein and tested pig sera were separately 1:320 and 1:5.The cut-off value of bELISA was 24.20%,and the sensitivity and specificity were 96.43 and 92.63%,respectively.By detecting 233 clinical pig sera with the developed bELISA and a commercial kit,the results showed that the coincidence rate of two assays was 93.99%.Additionallly,epitope mapping showed that PRV-gE-Nb36 recognized a conserved conformational epitope in different reference PRV strains.Simple,great stability and low-cost nanobody-based bELISA for detecting anti-PRV-gE antibodies were developed.The bELISA could be used for monitoring and eradicating PR.展开更多
BACKGROUND Epidural analgesia is the most effective analgesic method during labor.Butorphanol administered epidurally has been shown to be a successful analgesic method during labor.However,no comprehensive study has ...BACKGROUND Epidural analgesia is the most effective analgesic method during labor.Butorphanol administered epidurally has been shown to be a successful analgesic method during labor.However,no comprehensive study has examined the safety and efficacy of using butorphanol as an epidural analgesic during labor.AIM To assess butorphanol's safety and efficacy for epidural labor analgesia.METHODS The PubMed,Cochrane Library,EMBASE,Web of Science,China National Knowledge Infrastructure,and Google Scholar databases will be searched from inception.Other types of literature,such as conference abstracts and references to pertinent reviews,will also be reviewed.We will include randomized controlled trials comparing butorphanol with other opioids combined with local anesthetics for epidural analgesia during labor.There will be no language restrictions.The primary outcomes will include the visual analog scale score for the first stage of labor,fetal effects,and Apgar score.Two independent reviewers will evaluate the full texts,extract data,and assess the risk of bias.Publication bias will be evaluated using Egger's or Begg's tests as well as visual analysis of a funnel plot,and heterogeneity will be evaluated using the Cochran Q test,P values,and I2 values.Meta-analysis,subgroup analysis,and sensitivity analysis will be performed using RevMan software version 5.4.This protocol was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)Protocols statement,and the PRISMA statement will be used for the systematic review.RESULTS This study provides reliable information regarding the safety and efficacy of using butorphanol as an epidural analgesic during labor.CONCLUSION To support clinical practice and development,this study provides evidence-based findings regarding the safety and efficacy of using butorphanol as an epidural analgesic during labor.展开更多
BACKGROUND Awake fiberoptic nasotracheal intubation(AFNI)is the preferred airway ma-nagement strategy for patients with difficult airways.However,this procedure can cause significant physical and psychological distres...BACKGROUND Awake fiberoptic nasotracheal intubation(AFNI)is the preferred airway ma-nagement strategy for patients with difficult airways.However,this procedure can cause significant physical and psychological distress.This case report explores the application of a sphenopalatine ganglion(SPG)block as an alternative anal-gesic modality to mitigate the discomfort associated with AFNI.CASE SUMMARY A 63-year-old female with a history of right maxillary osteosarcoma underwent craniotomy for a suspected malignant brain lesion.The patient’s medical history included prior surgery,chemotherapy,and radiation therapy,resulting in signi-ficant jaw impairment and limited neck mobility.Considering the anticipated air-way challenges,AFNI was planned.A SPG block was performed under real-time ultrasound guidance,providing effective analgesia during nasotracheal intuba-tion.CONCLUSION The SPG block represents a promising analgesic approach in AFNI,offering po-tential benefits in alleviating pain involving the nasal and nasopharyngeal regions as well as improving patient cooperation.展开更多
Blockchain technology has witnessed a burgeoning integration into diverse realms of economic and societal development.Nevertheless,scalability challenges,characterized by diminished broadcast efficiency,heightened com...Blockchain technology has witnessed a burgeoning integration into diverse realms of economic and societal development.Nevertheless,scalability challenges,characterized by diminished broadcast efficiency,heightened communication overhead,and escalated storage costs,have significantly constrained the broad-scale application of blockchain.This paper introduces a novel Encode-and CRT-based Scalability Scheme(ECSS),meticulously refined to enhance both block broadcasting and storage.Primarily,ECSS categorizes nodes into distinct domains,thereby reducing the network diameter and augmenting transmission efficiency.Secondly,ECSS streamlines block transmission through a compact block protocol and robust RS coding,which not only reduces the size of broadcasted blocks but also ensures transmission reliability.Finally,ECSS utilizes the Chinese remainder theorem,designating the block body as the compression target and mapping it to multiple modules to achieve efficient storage,thereby alleviating the storage burdens on nodes.To evaluate ECSS’s performance,we established an experimental platformand conducted comprehensive assessments.Empirical results demonstrate that ECSS attains superior network scalability and stability,reducing communication overhead by an impressive 72% and total storage costs by a substantial 63.6%.展开更多
Geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkali...Geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkaline, strongly peraluminous rocks with A/CNK values of 1.37–1.46, are enriched in SiO2, K2O, and Rb, and are depleted in Nb, P, Ti, Eu, and heavy rare earth elements,which indicates the crystallization fractionation of the granitic magma. Zircon U–Pb dating indicates that they formed in ca. 480 Ma. The Nansa granites have εHf(t) values ranging from-16.04 to 4.36 with corresponding TC DMages of 2.10–0.81 Ga, which suggests the magmas derived from the partial melting of ancient metasedimentary with minor involvement of mantle-derived components. A synthesis of data for the Early Paleozoic igneous rocks in the Baoshan block and adjacent(Tengchong,Qiangtang, Sibumasu, Himalaya, etc.) blocks indicates that these blocks were all aligned along the proto-Tethyan margin of East Gondwana in the Early Paleozoic. The Early Paleozoic S-type granites from Nansa were generated in a high-temperature and low-pressure(HTLP) extensional tectonic setting, which resulted from Andean-type orogeny instead of the final assembly of Gondwana or crustal extension in a non-arc environment. In certain places, an expanding environment may exist in opposition to the tectonic backdrop of the lithosphere’s thickening and shortening, leading the crust to melt and decompress,mantle-derived materials to mix, and a small quantity of peraluminous granite to emerge.展开更多
Primary toppling usually occurs in layered rock slopes with large anti-dip angles.In this paper,the block toppling evolution was explored using a large-scale centrifuge system.Each block column in the layered model sl...Primary toppling usually occurs in layered rock slopes with large anti-dip angles.In this paper,the block toppling evolution was explored using a large-scale centrifuge system.Each block column in the layered model slope was made of cement mortar.Some artificial cracks perpendicular to the block column were prefabricated.Strain gages,displacement gages,and high-speed camera measurements were employed to monitor the deformation and failure processes of the model slope.The centrifuge test results show that the block toppling evolution can be divided into seven stages,i.e.layer compression,formation of major tensile crack,reverse bending of the block column,closure of major tensile crack,strong bending of the block column,formation of failure zone,and complete failure.Block toppling is characterized by sudden large deformation and occurs in stages.The wedge-shaped cracks in the model incline towards the slope.Experimental observations show that block toppling is mainly caused by bending failure rather than by shear failure.The tensile strength also plays a key factor in the evolution of block toppling.The simulation results from discrete element method(DEM)is in line with the testing results.Tensile stress exists at the backside of rock column during toppling deformation.Stress concentration results in the fragmented rock column and its degree is the most significant at the slope toe.展开更多
The Early Paleozoic tectono-thermal event was a significant orogenic activity during the Phanerozoic era,which had a profound impact on the early crust of the South China Block(SCB) and established the foundation for ...The Early Paleozoic tectono-thermal event was a significant orogenic activity during the Phanerozoic era,which had a profound impact on the early crust of the South China Block(SCB) and established the foundation for later tectonic activity.The Wuyi-Yunkai orogenic belt in Southeastern China was extensively exposed to Early Paleozoic magmatism,the genetic mechanism of which remains controversial.To shed light on this issue,detailed petrological,geochemical,and zircon U-Pb-Hf isotopic studies were carried out on two granitoids,namely the Yuntongshan pluton and the Gaoqiao pluton,identified in the central Wuyishan.Zircon U-Pb chronology of the Yuntongshan and Gaoqiao bodies yielded ages of437±4 Ma(MSWD=2.2) and 404±2 Ma(MSWD=12),respectively,indicating that they were emplaced during the Early Silurian and Early Devonian periods.These granitoids are primarily composed of biotite-granite and biotite-monzonitic-granites,with high concentrations of S_(i)O_(2)(73.59-75.91 wt%),K_(2)O+Na_(2)O(8.31-8.73wt%),and low contents of MgO,CaO,Cr,Ni.They are classified as high-K calc-alkaline and weakly metaluminous-strongly peraluminous S-type granites.These granitoids are enriched in light rare earth elements(LREEs) and large ion lithophile elements(LILEs) and depleted in heavy rare earth elements(HREEs) and high field strength elements(HFSEs) with arc affinity.The εHf(t) values of-3.3 to-15.4 with two-stage Hf model ages ranging from 2829 to 1644 Ma,combined with the presence of Neoproterozoic inherited zircons,suggest that the primary magma of these granitoids was derived from the partial melting of Neoproterozoic crust with a Paleoproterozoic crustal model age.These findings,combined with the spatio-temporal distribution of regional magmatism,reveal that the late Early-Paleozoic granitoids formed in the intraplate orogenic background originating from the subduction of the proto-Tethys Ocean and proto-Pacific Ocean around the margin of the east Gondwana supercontinent.展开更多
The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various industries.The conventional epoxy coating easily forms many intrinsic defects during the solidification proc...The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various industries.The conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient protection.In the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly technique.The outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)film.The FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier capability.The Ce film connects the outer layer with the substrate,showing the transition effect.The corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling behavior.The synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.展开更多
文摘Background: The rate of accidental dural puncture is particularly high during the period of training, especially in novices. The structured epidural teaching model (SETM) includes three standardized video lessons, the construction of a 3D epidural module by trainees and practical training by using an epidural simulator with and without the CompuFlo™ Epidural instrument. In this study we report the retrospective analysis of the accidental dural puncture rate of inexperienced trainees during their 6 months clinical practice rotation in obstetrics before and after the introduction of the SETM in our Institution. Method: We evaluated the incidence of accidental dural puncture before the introduction of the SETM methodology and afterwards by analyzing our departmental database from February 2019 to January 2023. All epidural blocks were executed by trainees who had never previously performed an epidural block and were about to begin their obstetrics rotation. Results: We analyzed 7415 epidurals: 3703 were performed before the introduction of the SETM methodology (control group) and 3712 afterwards (study group). The incidence of accidental dural puncture was 0.37% for the control group and 0.13% for the study group (p<.05). The probability of making an accidental dural puncture was 64% (OR: 0.36) lower for trainees who had the training than for those who did not. Conclusions: After the introduction of the structured teaching method, we observed a significant reduction of accidental dural puncture during the training period. We hope that our observation will encourage a constructive discussion among experts about the need to use standardized and validated tools as a valuable aid in teaching epidural anesthesia.
文摘BACKGROUND Chronic obstructive pulmonary disease(COPD)is associated with high morbidity and mortality rates worldwide.Older patients have a degenerative cardiopulmonary function,weak compensatory capacity,and poor surgical tolerance.Therefore,the mode of anesthesia must be optimized.Remimazolam is a new ultrashort-acting benzodiazepine with a rapid onset of action,rapid metabolism,and mild effects on pulmonary circulation.Remimazolam sedation combined with an epidural block has not been reported in hypertensive older adults with severe COPD and inguinal mass resection.CASE SUMMARY We report the case of a 73-year-old man with hypertension and severe COPD,who underwent resection of an enlarged inguinal mass that he had noticed more than 7 mo before presentation.The patient presented with a“right inguinal mass”and was recommended to undergo an enlarged inguinal mass resection.Surgery was relatively challenging,due to the large mass(13 cm×8 cm×7 cm),hard texture,and poor mobility.Considering the advanced age of the patient,gradeⅢhypertension,and severe COPD,we administered remimazolam combined with an epidural block for anesthesia to ensure perioperative safety and careful consideration.The anesthetic effect was precise;the procedure was performed smoothly without any complications,and the patient was successfully anesthetized.However,anesthetic management in such cases has not yet been reported by previous studies.CONCLUSION Remimazolam sedation combined with an epidural block is safe and effective in older patients with hypertension and severe COPD.
文摘Introduction: Video examples with task demonstrations by experts, with the expert’s eye movements superimposed on the task, are known as “eye movement modeling examples” (EMME). We performed this study to evaluate if there were improvements in the performance of anesthesia novice trainees when executing the epidural technique after an EMME of epidural block procedure. Methods: We developed an eye movement modeling example (EMME) from eye tracking recordings made by experienced anesthesiologists with more than 20 years of experience. Forty-two PGY3 anesthesia trainees who had never previously performed an epidural block were randomized to receive (study group) or not receive (control group) the EMME video before their institutional training. All the trainees were evaluated every 10 epidural blocks until the end of the rotation period, by an independent, blinded observer using the Global Rating Scale for Epidural Anesthesia (GRS). Results: Trainees who received the EMME training exhibited more respect for the patient’s tissues (P Discussion: This is the first study that has used the EMME for a practical, clinical teaching purpose on real patients and that has used it as an aid in teaching epidural anesthesia. We demonstrated that inexperienced trainees who received the EMME training improved their proficiency at epidural blocks as compared to those who had no EMME training beforehand. Given this result, we welcome further studies to investigate the impact and the role of EMME on clinical teaching in the field of anesthesia.
文摘<b>Background:</b> Poor postoperative pain control leads to longer postoperative care, longer hospital stay and decreased patient overall satisfaction. <b>Aim:</b> To compare the efficacy and safety of bilateral ultrasound-guided quadratus lumborum block versus lumbar epidural block on the management of postoperative pain following major lower abdominal cancer surgery. <b>Methods:</b> The study was a double-blinded, and randomized study, conducted in South Egypt Cancer Institute, Assiut University, Egypt. It included cancer patients scheduled for major lower abdominal cancer surgery in the period from 2019 to 2020. They were divided into two groups: Group Ι received pre-emptive ultrasound-guided Quadratus Lumborum Block (QLB) with 25 mL of 0.25% bupivacaine on each side of the abdominal wall before induction of General Anesthesia (GA), and Group II received pre-emptive lumbar epidural block with 15 mL of 0.25% bupivacaine before induction of GA. VAS score, and time of the first analgesic request and postoperative total analgesic consumption were evaluated. <b>Results:</b> Sixty patients were included in our study. VAS score at rest was comparable between both studied groups in the first 6 h. At 8 and 10 h, Group II had a significantly higher VAS score at rest (P < 0.001 and 0.026 respectively). Meanwhile, at 12 h, patients in Group I had a significantly higher VAS score (P = 0.026). Mean time of the first request for rescue analgesia was significantly prolonged in Group I (13.27 ± 2.38 hrs.) compared to Group II (10.20 ± 1.42 hrs.) (P < 0.001) respectively, mean total morphine consumption, over the first 24 hours postoperatively, was significantly lower in Group I (5.17 ± 1.32 mg) than in Group II (7.33 ± 1.45 mg) (P < 0.001). A larger number of patients in Group II had nausea at different time points postoperatively than in Group I (P < 0.001), but no significant difference was observed between both studied groups regarding the incidence of vomiting. <b>Limitation:</b> Small sample size and shorter period for postoperative follow-up. <b>Conclusions:</b> Management of postoperative pain following major lower abdominal cancer surgery with US-guided QLB was associated with the reduction in the total analgesic consumption and delayed the first request of analgesia as compared to lumbar epidural block technique.
文摘Background: Pneumatic arterial tourniquet is a very commonly used technique in limb surgeries to provide bloodless field to facilitate dissection and decrease blood loss. However, arterial tourniquet has many deleterious effects including hemodynamic changes, serum lactate and potassium level changes and tourniquet-induced pain which sometimes can be severe and intolerable. Aim of the study: To evaluate the effect of different regional blocks: femoral-sciatic, spinal and epidural blocks on serum lactate and potassium levels and the degree of arterial tourniquet-induced pain in patients undergoing lower limb orthopedic surgeries. Methods: 60 patients underwent lower limb orthopedic surgery with application of tourniquet for duration not more than 90 minutes. Patients were assigned randomly to one of three groups (20 each) Group I had sciatic-femoral block, Group II: patients had spinal anesthesia and Group III: patients had epidural anesthesia. Intraoperative hemodynamics, changes in serum potassium and lactate levels and tourniquet pain after tourniquet inflation & deflation, were recorded. Results: There was no statistically significant difference among the three groups regarding tourniquet pain after tourniquet inflation (p = 0.872) and deflation (p = 0.902), and regarding serum levels changes of potassium (p = 0.067) and lactate (p = 0.051). However, each group showed statistically significant increase in post deflation tourniquet pain (p = 0.003, 0.002, 0.003, in groups F, S, E respectively) and serum potassium (p = 0.004, 0.006, 0.000, in groups F, S, E respectively) and lactate levels (p = 0.004, 0.000, 0.000, in groups F, S, E respectively) when compared to the pre-deflation values, and the increase was directly proportional to the duration of tourniquet. Conclusion: the three different types of anesthesia (femoral-sciatic, spinal and epidural block) have the same effect on serum lactate and potassium levels and the degree of tourniquet pain, which were related to the duration of tourniquet inflation.
文摘Objective: To investigate the effect of epidural block combined with intravenous anesthesia on stress response and T lymphocyte subsets in patients with breast cancer undergoing radical mastectomy. Methods: In our hospital from July 2016 to June 2017 undergoing radical mastectomy for breast cancer of 88 patients were randomly divided into observation group and control group of 44 cases, 2 patients underwent routine preoperative preparation, and routine blood pressure, heart rate, pulse, oxygen saturation, ECG monitoring, control group with intravenous anesthesia. The observation group was treated with epidural block combined with intravenous anesthesia. 2 groups of patients before anesthesia, 30 MIM (T0), 1 h after skin incision (T1), 4 h after operation (T2), 24 h after operation (T3), 48 h after operation (T4) from peripheral venous blood were measured by interleukin-8 (IL-8) and interferon gamma (IFN-γ), cortisol (Cor), prolactin (PRL), growth hormone (GH) and T lymphocyte subsets (CD3+, CD4+, CD8+), the calculation of CD4+/CD8+ value. Results: the serum IL-8 level of T1, T2, T3and T4 decreased gradually, were lower than at T0, and the control group at each time point had no significant difference, T1, T2, T3group, T4IL-8 levels lower than the control group;the 2 groups of serum IFN-γ levels T1 and T2had no significant change, T3and T4increased gradually, was higher than that of T0, but no significant difference between the 2 groups of IFN-γ levels. 2 serum Cor levels peaked at T1, decreased at T2, was higher than that of T0, T3, T4returned to T0, the observation group T1, T2Cor level lower than the control group;the serum PRL levels of 2 groups reached a peak at T1, T2, T3at the time of T4decreased gradually, was higher than that of T0, T1, T2, T3of the observation group at the PRL level is lower than the control group;the serum level of GH 2 in group T1increased gradually, reached a peak at T2, T3and T4 decreased gradually, was higher than that of T0, the observation group T1, T2, T3, T4, GH levels lower than the control group. 2 groups of CD3+ decreased gradually in T1, T2, were lower than T0, T3, T4returned to T0, the observation group T1, T2CD3+ was higher than the control group;group CD4+ decreased gradually in T1, T2, T3and T4were lower than control, T0when, and the observation group CD4+ in T1, T2, T3, T4, no significant changes were observed in group T1, T2, T3, T4and CD4+ higher than that of the control group;the 2 group CD8+ had no obvious changes in T1, T2, T3, T4;observation group CD4+/CD8+ decreased gradually in T1, T2, were lower than T0, T3, T4returned to T0, the observation group T1, T2CD4+/CD8+ was higher than the control group. Conclusion: epidural block combined with intravenous anesthesia for breast cancer radical mastectomy can effectively relieve the stress and inflammatory reaction, alleviate the immunosuppression, and help to restore the postoperative immune function.
文摘Background: The study was done to assess the postoperative analgesic efficacy of ultrasound-guided continuous transverses abdominis plane block, continuous lumbar paravertebral block and a continuous lumbar epidural block in patients undergoing lower abdominal surgeries (unilateral inguinal hernia repair). We compared their analgesic efficacy over the first 48 hour postoperative, in a randomized, single-blind study in 120 patients divided into four equal groups, 30 patients in each group. Methods: 120 patients randomly assigned into four equal groups, with 30 patients in each group. Group T received ultrasound-guided transverses abdominis plane block with 20 ml of bupivacaine 0.25% followed by continuous infusion of bupivacaine 0.125% (0.1 ml/kg/hr) and group P received ultrasound-guided continuous lumbar paravertebral block with bupivacaine 0.25% bolus dose 20 ml, followed by continuous infusion of bupivacaine 0.125% (0.1 ml/kg/hr). Group E received continuous lumbar epidural infusion of bupivacaine 0.25% bolus dose 20 ml, followed by continuous infusion of bupivacaine 0.125% (0.1 ml/kg/hr) and group C received normal saline bolus dose 20 ml, followed by continuous infusion of normal saline (0.1 ml/kg/hr). General anesthesia induced with fentanyl 1 - 2 μg/kg and propofol 1 - 3 mg/kg followed by atracurium 0.5 mg/kg. At the end of the surgical procedure, we activated the regional block with recording of parameters in the postoperative period each patient was assessed for visual analog scale (VAS) at rest and on movement, analgesic consumption, vital signs and presence of complications (nausea, vomiting, sedation), and postoperative patient satisfaction all data collected postoperatively by a blinded investigator at one, two, 6, 12, 24 and 48 hours postoperatively. Results: Postoperative analgesic efficacy is more in group E than group P and group T, the latter is least effective in pain control. Also in group E the postoperative analgesic consumption is lower than in group P and group T, re-garding complications as nausea and vomiting more recorded in epidural than the other two groups. Conclusion: Regarding postoperative analgesic efficacy, the continuous lumbar epidural block is more effective than continuous paravertebral and continuous transverses abdominis plane block, but regarding complications, there was a higher incidence in epidural group than other two groups.
文摘BACKGROUND Symptomatic cervical facet cysts are relatively rare compared to those in the lumbar region.These cysts are usually located in the 7th cervical and 1st thoracic vertebral(C7/T1)area,and surgical excision is performed in most cases.However,facet cysts are associated with degenerative conditions,and elderly patients are often ineligible for surgical procedures.Cervical interlaminar epidural block has been used in patients with cervical radiating symptoms and achieved good results.Therefore,cervical interlaminar epidural block may be the first-choice treatment for symptomatic cervical facet cysts.CASE SUMMARY A 70-year-old man complained of a tingling sensation in the left hand,focused on the 4th and 5th fingers,for 1 year,and posterior neck pain for over 5 mo.The patient’s numeric rating scale(NRS)score was 5/10.The patient was diagnosed with symptomatic cervical facet cyst at the left C7/T1 facet joint.Fluoroscopyguided cervical interlaminar epidural block at the C7/T1 level with 20 mg triamcinolone and 5 mL of 0.5%lidocaine was administered.The patient's symptoms improved immediately after the block,with an NRS score of 3 points.After 3 mo,his left posterior neck pain and tingling along the left 8th cervical dermatome were relieved,with an NRS score of 2.CONCLUSION A cervical interlaminar epidural block is a good alternative for managing symptomatic cervical facet cysts.
基金Changning District Health Commission Medical Key(Characteristic)Specialized Program,No.20192003.
文摘BACKGROUND The background of this study was analgesia in natural delivery.The combined spinal-epidural anesthesia has obvious analgesic effect on the parturients in natural labor,and combined spinal-epidural anesthesia has been widely used in anesthesia for various diseases.AIM To study the effects of combined spinal-epidural anesthesia on anxiety,labor analgesia,and motor blocks in parturients during natural delivery.METHODS A total of 120 women who gave birth at Changning District Maternal and Child Health Hospital between December 2021 to December 2022 were included;a random number table approach was employed to divide the women into a control group and a joint group,with each group consisting of 60 women.The control group was given epidural anesthesia,while the joint group was given combined spinal-epidural anesthesia.The visual analog scale(VAS)was used to evaluate the degree of maternal pain.Comparisons were made between the two groups’conditions of childbirth and the duration of labor.Apgar scores were used to evaluate the status of the newborns at birth;Self-rating Anxiety Scale(SAS)and General Self-Efficacy Scale(GSES)scores,umbilical artery blood gas analysis indices and stress indices were compared between the two groups;and the frequencies of motor block and postpartum complications were analyzed.RESULTS In comparison to the control group,in the joint group,the VAS scores for the first,second,and third stages of labor were lower(P<0.05).The rates of conversion to cesarean section and postpartum blood loss in the joint group were lower than those in the control group(P<0.05).No significant differences were observed in the Apgar score,the duration of the first stage of labor,or the total duration of labor between the two groups(P>0.05).The second and third stages of labor in the joint group were shorter than those in the control group(P<0.05).When compared to the control group,the postpartum SAS score of the joint group was lower,while the GSES score was greater(P<0.05).Between the control group and the joint group,the differences observed in pH,arterial carbon dioxide partial pressure,arterial oxygen partial pressure,or arterial hydrogen ion concentration were not significant(P>0.05).Nitric oxide,cortisol,and adrenaline levels were lower in the joint group than in the control group(P<0.05).There were no substantial differences in Bromage grade or rate of complications between the two groups(P>0.05).CONCLUSION For parturients during natural delivery,combined spinal-epidural anesthesia can reduce anxiety,provide labor analgesia,shorten labor time,and reduce postoperative stress levels but did not result in a motor block.
基金supported by the National Natural Science Foundation of China(32273041)the Key R&D Program of Shaanxi Province,China(2022NY-104)the Natural Science Foundation of Shaanxi Province,China(2022JC-12)。
文摘Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry worldwide.PRV glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ELISA)has been used to distinguish gE-deleted vaccine-immunized pigs from wild-type virus-infected pigs to eradicate PR in some countries.Nanobody has the advantages of small size and easy genetic engineering and has been a promising diagnostic reagent.However,there were few reports about developing nanobody-based ELISA for detecting anti-PRV-gE antibodies.In the present study,the recombinant PRV-gE was expressed with a bacterial system and used to immunize the Bactrian camel.Then,two nanobodies against PRV-gE were screened from the immunized camel by phage display technique.Subsequently,two nanobody-HRP fusion proteins were expressed with HEK293T cells.The PRV-gE-Nb36-HRP fusion protein was selected as the probe for developing the blocking ELISA(bELISA)to detect anti-PRV-gE antibodies.Through optimizing the conditions of bELISA,the amount of coated antigen was 200 ng per well,and dilutions of the fusion protein and tested pig sera were separately 1:320 and 1:5.The cut-off value of bELISA was 24.20%,and the sensitivity and specificity were 96.43 and 92.63%,respectively.By detecting 233 clinical pig sera with the developed bELISA and a commercial kit,the results showed that the coincidence rate of two assays was 93.99%.Additionallly,epitope mapping showed that PRV-gE-Nb36 recognized a conserved conformational epitope in different reference PRV strains.Simple,great stability and low-cost nanobody-based bELISA for detecting anti-PRV-gE antibodies were developed.The bELISA could be used for monitoring and eradicating PR.
文摘BACKGROUND Epidural analgesia is the most effective analgesic method during labor.Butorphanol administered epidurally has been shown to be a successful analgesic method during labor.However,no comprehensive study has examined the safety and efficacy of using butorphanol as an epidural analgesic during labor.AIM To assess butorphanol's safety and efficacy for epidural labor analgesia.METHODS The PubMed,Cochrane Library,EMBASE,Web of Science,China National Knowledge Infrastructure,and Google Scholar databases will be searched from inception.Other types of literature,such as conference abstracts and references to pertinent reviews,will also be reviewed.We will include randomized controlled trials comparing butorphanol with other opioids combined with local anesthetics for epidural analgesia during labor.There will be no language restrictions.The primary outcomes will include the visual analog scale score for the first stage of labor,fetal effects,and Apgar score.Two independent reviewers will evaluate the full texts,extract data,and assess the risk of bias.Publication bias will be evaluated using Egger's or Begg's tests as well as visual analysis of a funnel plot,and heterogeneity will be evaluated using the Cochran Q test,P values,and I2 values.Meta-analysis,subgroup analysis,and sensitivity analysis will be performed using RevMan software version 5.4.This protocol was developed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)Protocols statement,and the PRISMA statement will be used for the systematic review.RESULTS This study provides reliable information regarding the safety and efficacy of using butorphanol as an epidural analgesic during labor.CONCLUSION To support clinical practice and development,this study provides evidence-based findings regarding the safety and efficacy of using butorphanol as an epidural analgesic during labor.
文摘BACKGROUND Awake fiberoptic nasotracheal intubation(AFNI)is the preferred airway ma-nagement strategy for patients with difficult airways.However,this procedure can cause significant physical and psychological distress.This case report explores the application of a sphenopalatine ganglion(SPG)block as an alternative anal-gesic modality to mitigate the discomfort associated with AFNI.CASE SUMMARY A 63-year-old female with a history of right maxillary osteosarcoma underwent craniotomy for a suspected malignant brain lesion.The patient’s medical history included prior surgery,chemotherapy,and radiation therapy,resulting in signi-ficant jaw impairment and limited neck mobility.Considering the anticipated air-way challenges,AFNI was planned.A SPG block was performed under real-time ultrasound guidance,providing effective analgesia during nasotracheal intuba-tion.CONCLUSION The SPG block represents a promising analgesic approach in AFNI,offering po-tential benefits in alleviating pain involving the nasal and nasopharyngeal regions as well as improving patient cooperation.
文摘Blockchain technology has witnessed a burgeoning integration into diverse realms of economic and societal development.Nevertheless,scalability challenges,characterized by diminished broadcast efficiency,heightened communication overhead,and escalated storage costs,have significantly constrained the broad-scale application of blockchain.This paper introduces a novel Encode-and CRT-based Scalability Scheme(ECSS),meticulously refined to enhance both block broadcasting and storage.Primarily,ECSS categorizes nodes into distinct domains,thereby reducing the network diameter and augmenting transmission efficiency.Secondly,ECSS streamlines block transmission through a compact block protocol and robust RS coding,which not only reduces the size of broadcasted blocks but also ensures transmission reliability.Finally,ECSS utilizes the Chinese remainder theorem,designating the block body as the compression target and mapping it to multiple modules to achieve efficient storage,thereby alleviating the storage burdens on nodes.To evaluate ECSS’s performance,we established an experimental platformand conducted comprehensive assessments.Empirical results demonstrate that ECSS attains superior network scalability and stability,reducing communication overhead by an impressive 72% and total storage costs by a substantial 63.6%.
基金funded by the National Natural Science Foundation of China (2019M653840XB)the National Natural Science Foundation of China (41972043 and 42062006)。
文摘Geochemistry, zircon U–Pb geochronology, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkaline, strongly peraluminous rocks with A/CNK values of 1.37–1.46, are enriched in SiO2, K2O, and Rb, and are depleted in Nb, P, Ti, Eu, and heavy rare earth elements,which indicates the crystallization fractionation of the granitic magma. Zircon U–Pb dating indicates that they formed in ca. 480 Ma. The Nansa granites have εHf(t) values ranging from-16.04 to 4.36 with corresponding TC DMages of 2.10–0.81 Ga, which suggests the magmas derived from the partial melting of ancient metasedimentary with minor involvement of mantle-derived components. A synthesis of data for the Early Paleozoic igneous rocks in the Baoshan block and adjacent(Tengchong,Qiangtang, Sibumasu, Himalaya, etc.) blocks indicates that these blocks were all aligned along the proto-Tethyan margin of East Gondwana in the Early Paleozoic. The Early Paleozoic S-type granites from Nansa were generated in a high-temperature and low-pressure(HTLP) extensional tectonic setting, which resulted from Andean-type orogeny instead of the final assembly of Gondwana or crustal extension in a non-arc environment. In certain places, an expanding environment may exist in opposition to the tectonic backdrop of the lithosphere’s thickening and shortening, leading the crust to melt and decompress,mantle-derived materials to mix, and a small quantity of peraluminous granite to emerge.
基金The authors wish to thank National Key R&D Program of China(Grant No.2022YFC308100)the National Nature Science Foundation of China(Grant Nos.42107172 and 42072303)for financial support.
文摘Primary toppling usually occurs in layered rock slopes with large anti-dip angles.In this paper,the block toppling evolution was explored using a large-scale centrifuge system.Each block column in the layered model slope was made of cement mortar.Some artificial cracks perpendicular to the block column were prefabricated.Strain gages,displacement gages,and high-speed camera measurements were employed to monitor the deformation and failure processes of the model slope.The centrifuge test results show that the block toppling evolution can be divided into seven stages,i.e.layer compression,formation of major tensile crack,reverse bending of the block column,closure of major tensile crack,strong bending of the block column,formation of failure zone,and complete failure.Block toppling is characterized by sudden large deformation and occurs in stages.The wedge-shaped cracks in the model incline towards the slope.Experimental observations show that block toppling is mainly caused by bending failure rather than by shear failure.The tensile strength also plays a key factor in the evolution of block toppling.The simulation results from discrete element method(DEM)is in line with the testing results.Tensile stress exists at the backside of rock column during toppling deformation.Stress concentration results in the fragmented rock column and its degree is the most significant at the slope toe.
基金supported by the National Natural Science Foundation of China (No.41702204)the Central Fundamental Research (grant number DZLXJK201504)the Major State Research Development Program of China (grant number 2016YFC0600202)。
文摘The Early Paleozoic tectono-thermal event was a significant orogenic activity during the Phanerozoic era,which had a profound impact on the early crust of the South China Block(SCB) and established the foundation for later tectonic activity.The Wuyi-Yunkai orogenic belt in Southeastern China was extensively exposed to Early Paleozoic magmatism,the genetic mechanism of which remains controversial.To shed light on this issue,detailed petrological,geochemical,and zircon U-Pb-Hf isotopic studies were carried out on two granitoids,namely the Yuntongshan pluton and the Gaoqiao pluton,identified in the central Wuyishan.Zircon U-Pb chronology of the Yuntongshan and Gaoqiao bodies yielded ages of437±4 Ma(MSWD=2.2) and 404±2 Ma(MSWD=12),respectively,indicating that they were emplaced during the Early Silurian and Early Devonian periods.These granitoids are primarily composed of biotite-granite and biotite-monzonitic-granites,with high concentrations of S_(i)O_(2)(73.59-75.91 wt%),K_(2)O+Na_(2)O(8.31-8.73wt%),and low contents of MgO,CaO,Cr,Ni.They are classified as high-K calc-alkaline and weakly metaluminous-strongly peraluminous S-type granites.These granitoids are enriched in light rare earth elements(LREEs) and large ion lithophile elements(LILEs) and depleted in heavy rare earth elements(HREEs) and high field strength elements(HFSEs) with arc affinity.The εHf(t) values of-3.3 to-15.4 with two-stage Hf model ages ranging from 2829 to 1644 Ma,combined with the presence of Neoproterozoic inherited zircons,suggest that the primary magma of these granitoids was derived from the partial melting of Neoproterozoic crust with a Paleoproterozoic crustal model age.These findings,combined with the spatio-temporal distribution of regional magmatism,reveal that the late Early-Paleozoic granitoids formed in the intraplate orogenic background originating from the subduction of the proto-Tethys Ocean and proto-Pacific Ocean around the margin of the east Gondwana supercontinent.
基金the National Natural Science Foundation of China(Grant number 51771178)Shaanxi Outstanding Youth Fund project(Grant number 2021JC-45)+2 种基金Key international cooperation projects in Shaanxi Province(Grant number 2020KWZ-007)the Major Program of Science and Technology in Shaanxi Province(Grant number20191102006)Open Fund of State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body(Grant number 32115019)。
文摘The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various industries.The conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient protection.In the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly technique.The outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)film.The FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier capability.The Ce film connects the outer layer with the substrate,showing the transition effect.The corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling behavior.The synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.
