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The Incidence and Risk Factors of Third- and Fourth-Degree Perineal Tears in Ministry of Health in Bahrain over 5 Years
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作者 Fatema Ahmed Basma Alsayegh +1 位作者 Bayan Ahmed Amal Hassani 《Open Journal of Obstetrics and Gynecology》 2024年第7期1060-1073,共14页
Background: Perineal trauma and vaginal laceration are considered a common complication associated with vaginal delivery. Well established risk factors, recognized by the Royal College of Obstetricians and Gynecologis... Background: Perineal trauma and vaginal laceration are considered a common complication associated with vaginal delivery. Well established risk factors, recognized by the Royal College of Obstetricians and Gynecologists, are ethnicity, birth weight over 4 kg persistent occipital posterior position, null parity, induction of labor, shoulder dystocia, instrumental delivery. There are other risk factors that were suggested in the literature, but data are conflicting, such as prolonged second stage of labor, episiotomy and obesity. Objective: To evaluate third- and fourth-degree perineal rears rates and the impact of related risk factors on perineal tears in Ministry of health in Bahrain over 5 years (which includes Salmanyia Medical complex (SMC) and Jidhafs maternity hospital (JMH)). Methods: This retrospective descriptive cross-sectional study analyzed all vaginal deliveries from January 2015 to December 2019 in Obstetrics and Gynecology department in Salmanyia Medical Complex (the main hospital in Kingdom of Bahrain which received all kinds of cases including low and high risks) and Jidhafs Maternity Hospital (tertiary hospital which received only low risk cases), Kingdom of Bahrain. During the period of interest 33,694 records were identified. Data were extracted from observational recording from SMC and JMH labour registry books. Results: There was no statistically significant difference between groups according to age (p = 0.199). On the other hand, there was statistically significant higher cases of >40 weeks at gestational age, obesity > 35 kg/mr, vacuum delivery, pushing stage > 90 min, birth weight > 4 kg, head circumference > 34 cm, fetal length at birth > 50 cm, episiotomy and lower cases of nulliparity in study group compared to control group 16 (66.7%) vs. 13,805 (41.0%), 3 (12.5%) vs. 1448 (4.3%), 3 (12.5%) vs. 1414 (4.2%), 4 (16.7%) vs. 1751 (5.2%), 3 (12.5%) vs. 1751 (5.2%), 12 (50.0%) vs. 15,926 (47.3%), 15 (62.5%) vs. 20,135 (59.8%) and 17 (70.8%) vs. 29,024 (86.2%);(p = 0.027, 0.009, Conclusion: Gestational age > 40 weeks, obesity > 35 kg/mr, pushing stage > 90 min, birth weight > 4 kg, head circumference > 34 cm, fetal length at birth > 50 cm and using of vacuum increase incidence of 3rd and 4th degree perineal tears with vaginal delivery however maternal age and nulliparity have no significant role. Finally, episiotomy did not represent as protective factor for perineal damage. . 展开更多
关键词 Perineal tears Vaginal Laceration Vaginal Delivery
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Preliminary proteomic analysis of human tears in lacrimal adenoid cystic carcinoma and pleomorphic adenoma 被引量:1
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作者 Han Yue Feng-Xi Meng +1 位作者 Rui Zhang Jiang Qian 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第6期841-848,共8页
·AIM: To detect proteomic differences in tears between adenoid cystic carcinoma(ACC) and pleomorphic adenoma(PA).·METHODS: Tear samples were collected from 4 patients with ACC, 5 with PA, and 4 control cases... ·AIM: To detect proteomic differences in tears between adenoid cystic carcinoma(ACC) and pleomorphic adenoma(PA).·METHODS: Tear samples were collected from 4 patients with ACC, 5 with PA, and 4 control cases. Label-free analysis and parallel reaction monitoring(PRM) were used to screen and validate the tear proteome. Gene Ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) were conducted for bioinformatics analysis.·RESULTS: In total, 1059 proteins in tear samples were identified by label-free analysis. Between ACC and PA, 415 differentially expressed proteins were detected. Based on the GO annotation, enzyme regulator activity and serinetype endopeptidase inhibitor activity in the molecular function category, blood microparticle and extracellular matrix in the cellular component category, and response to nutrient levels in the biological process category were most predominant. By KEGG pathway annotation, the different proteins between ACC and PA mainly par ticipated in complement and coagulation cascades, amoebiasis, African trypanosomiasis and cholesterol metabolism. Eight proteins with mostly significant differences were verified by PRM, and five proteins with more than 10-fold increases in ACC compared with PA, including integrin β, α-2-macroglobulin, epididymal secretory sperm binding protein Li 78p, RAB5C, and complement C5, were identified.·CONCLUSION: The combined tools of label-free analysis and PRM are very effective and efficient, especially for samples such as tears. Some proteomic dif ferences in tears between ACC and PA are identified and these protein candidates may be specific biomarkers for future exploration. 展开更多
关键词 adenoid cystic carcinoma pleomorphic adenoma tear PROTEOME
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Long head of biceps tendon transposition for massive and irreparable rotator cuff tears:A systematic review and meta-analysis 被引量:1
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作者 Ren-Wen Wan Zhi-Wen Luo +4 位作者 Yi-Meng Yang Han-Li Zhang Jia-Ni Chen Shi-Yi Chen Xi-Liang Shang 《World Journal of Orthopedics》 2023年第11期813-826,共14页
BACKGROUND Superior capsular reconstruction(SCR)with long head of biceps tendon(LHBT)transposition was developed to massive and irreparable rotator cuff tears(MIRCTs);however,the outcomes of this technique remain uncl... BACKGROUND Superior capsular reconstruction(SCR)with long head of biceps tendon(LHBT)transposition was developed to massive and irreparable rotator cuff tears(MIRCTs);however,the outcomes of this technique remain unclear.AIM To perform a systematic review of biomechanical outcomes and a meta-analysis of clinical outcomes after LHBT transposition for MIRCTs.METHODS We performed a systematic electronic database search on PubMed,EMBASE,and Cochrane Library.Studies of SCR with LHBT transposition were included according to the inclusion and exclusion criteria.Biomechanical studies were assessed for main results and conclusions.Included clinical studies were evaluated for quality of methodology.Data including study characteristics,cohort demographics,and outcomes were extracted.A meta-analysis was conducted of the clinical outcomes.RESULTS According to our inclusion and exclusion criteria,a total of six biomechanical studies were identified and reported an overall improvement in subacromial contact pressures and prevention of superior humeral migration without limiting range of motion(ROM)after LHBT transposition for MIRCTs.A total of five clinical studies were included in the meta-analysis of LHBT transposition outcomes,consisting of 253 patients.The results indicated that compared to other surgical methods for MIRCTs,LHBT transposition had advantages of more significant improvement in ROM(forward flexion mean difference[MD]=6.54,95%confidence interval[CI]:3.07-10.01;external rotation[MD=5.15,95%CI:1.59-8.17];the acromiohumeral distance[AHD][MD=0.90,95%CI:0.21-1.59])and reducing retear rate(odds ratio=0.27,95%CI:0.15-0.48).No significant difference in American Shoulder and Elbow Surgeons score,visual analogue scale score,and University of California at Los Angles score was demonstrated between these two groups for MIRCTs.CONCLUSION In general,SCR with LHBT transposition was a reliable and economical technique for treating MIRCTs,both in terms of biomechanical and clinical outcomes,with comparable clinical outcomes,improved ROM,AHD,and reduced the retear rates compared to conventional SCR and other established techniques.More high-quality randomized controlled studies on the long-term outcomes of SCR with LHBT transposition are required to further assess. 展开更多
关键词 Massive and irreparable rotator cuff tears Long head of biceps tendon transposition Rotator cuff repair Superior capsular reconstruction
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Meniscus tears treatment:The good,the bad and the ugly-patterns classification and practical guide
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作者 Roberto Simonetta Arcangelo Russo +2 位作者 Michelangelo Palco Giuseppe Gianluca Costa Pier Paolo Mariani 《World Journal of Orthopedics》 2023年第4期171-185,共15页
Over the years,several studies demonstrated the crucial role of knee menisci in joint biomechanics.As a result,save the meniscus has become the new imperative nowadays,and more and more studies addressed this topic.Th... Over the years,several studies demonstrated the crucial role of knee menisci in joint biomechanics.As a result,save the meniscus has become the new imperative nowadays,and more and more studies addressed this topic.The huge amount of data on this topic may create confusion in those who want to approach this surgery.The aim of this review is to provide a practical guide for treatment of meniscus tears,including an overview of technical aspects,outcomes in the literature and personal tips.Taking inspiration from a famous movie directed by Sergio Leone in 1966,the authors classified meniscus tears in three categories:The good,the bad and the ugly lesions.The inclusion in each group was determined by the lesion pattern,its biomechanical effects on knee joint,the technical challenge,and prognosis.This classification is not intended to substitute the currently proposed classifications on meniscus tears but aims at offering a readerfriendly narrative review of an otherwise difficult topic.Furthermore,the authors provide a concise premise to deal with some aspects of menisci phylogeny,anatomy and biomechanics. 展开更多
关键词 MENISCUS Meniscus anatomy Meniscus tear Meniscus repair Root lesion Ramp lesion
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Late presentation of dural tears:Two case reports and review of literature
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作者 Chang Xu Rong-Peng Dong +1 位作者 Xue-Liang Cheng Jian-Wu Zhao 《World Journal of Clinical Cases》 SCIE 2023年第11期2464-2473,共10页
BACKGROUND The late presentation of dural tears(LPDT)has a low incidence rate and hidden symptoms and is easily ignored in clinical practice.If the disease is not treated in time,a series of complications may occur,in... BACKGROUND The late presentation of dural tears(LPDT)has a low incidence rate and hidden symptoms and is easily ignored in clinical practice.If the disease is not treated in time,a series of complications may occur,including low intracranial pressure headache,infection,pseudodural cyst formation,and sinus formation.Here,we describe two cases of LPDT.CASE SUMMARY Two patients had sudden fever 1 wk after lumbar surgery.Physical examination showed obvious tenderness in the operation area.The patients were confirmed as having LPDT by lumbar magnetic resonance imaging and surgical exploration.One case was caused by continuous negative pressure suction and malnutrition,and the other was caused by decreased dural ductility and low postoperative nutritional status.The first symptom of both patients was fever,with occasional headache.Both patients underwent secondary surgery to treat the LPDT.Dural defects were observed and dural sealants were used to seal the dural defects,then drainage tubes were retained for drainage.After the operation,the patients were treated with antibiotics and the patients’surgical incisions healed well,without fever or incision tenderness.Both recovered and were discharged 1 wk after the operation.CONCLUSION LPDT is a rare complication of spinal surgery or neurosurgery that has hidden symptoms and can easily be overlooked.Since it may cause a series of complic-ations,LPDT needs to be actively addressed in clinical practice. 展开更多
关键词 Late presentation of dural tears Delayed cerebrospinal fluid leakage Dural repair FACTORS Clinical management Case report
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Assessment of tear film parameters post-treatment with commercial eyelid cleaning wipes:a pilot study
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作者 Amal Aldarwesh Ali Almustanyir +7 位作者 Raied Fagehi Khalaf Alruways Abdulaziz Bin Turki Mansour Alghamdi Muteb Khalaf Alanazi Balsam Alabdulkader Wafa Alotaibi Mosaad Alhassan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第4期659-664,共6页
AIM:To investigate the short-term effects of commercially available eyelid-cleaning wipes on film parameters.METHODS:This study enrolled 48 healthy participants aged 20-35y(both males and females).Clinical assessment ... AIM:To investigate the short-term effects of commercially available eyelid-cleaning wipes on film parameters.METHODS:This study enrolled 48 healthy participants aged 20-35y(both males and females).Clinical assessment included the Ocular Surface Disease Index(OSDI)questionnaire,non-invasive tear break-up time(NITBUT),tear meniscus height(TMH),and lipid layer pattern(LLP).Based on these initial results,participants were categorized as either non-dry eye or dry eye.Participants in each group were randomly allocated to either Blephaclean■or Systane■treatments.Changes in NITBUT,TMH,and LLP levels before and after lid wipe treatment were assessed.RESULTS:The dry eye group exhibited significantly higher OSDI scores and lower NITBUT and TMH levels than in the non-dry eye group(P<0.001).Following the application of eyelid wipes(Systane■wipes),dry eye subjects experienced a significant improvement in NITBUT levels(P=0.0014)compared to the non-dry eye individuals.Although the remaining participants showed a marginal increase in TMH and NITBUT levels,these changes did not achieve statistical significance(P>0.05).Similarly,the LLP levels were significantly improved with Systane■(P<0.001)post-treatment compared to individuals in the non-dry eye group.However,the dry eye subjects showed higher posttreatment LLP levels than the untreated group(P<0.02).CONCLUSION:The short-term effects of Systane®eyelid wipes on tear film parameters suggest their effectiveness in dry eye disease.Nonetheless,further exploration of their long-term impact is essential to justify their cost effectiveness and efficacy in treating both aqueous deficiency and evaporative dryness. 展开更多
关键词 dry eye lid wipes tear break-up time tear meniscus height
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Suppression of the m/n=2/1 tearing mode by electron cyclotron resonance heating on J-TEXT
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作者 方建港 陈忠勇 +13 位作者 严伟 王能超 毛飞越 罗蔷 玄子健 陈曦璇 任正康 张峰 黄梅 夏冬辉 杨州军 陈志鹏 丁永华 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期8-17,共10页
Stabilization of tearing modes and neoclassical tearing modes is of great importance for tokamak operation.Electron cyclotron waves(ECWs)have been extensively used to stabilize the tearing modes with the virtue of hig... Stabilization of tearing modes and neoclassical tearing modes is of great importance for tokamak operation.Electron cyclotron waves(ECWs)have been extensively used to stabilize the tearing modes with the virtue of highly localized power deposition.Complete suppression of the m/n=2/1 tearing mode(TM)by electron cyclotron resonance heating(ECRH)has been achieved successfully on the J-TEXT tokamak.The effects of ECW deposition location and power amplitude on the 2/1 TM suppression have been investigated.It is found that the suppression is more effective when the ECW power is deposited closer to the rational surface.As the ECW power increases to approximately 230 k W,the 2/1 TM can be completely suppressed.The island rotation frequency is increased when the island width is reduced.The experimental results show that the local heating inside the magnetic island and the resulting temperature perturbation increase at the O-point of the island play dominant roles in TM suppression.As the ECW power increases,the 2/1 island is suppressed to smaller island width,and the flow shear also plays a stabilizing effect on small magnetic islands.With the stabilizing contribution of heating and flow shear,the 2/1 TM can be completely suppressed. 展开更多
关键词 tearing mode electron cyclotron resonant heating tearing mode suppression
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Pro-inflammatory cytokines levels in tears and dry eye disease in Parkinson’s disease
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作者 Azyadeh Camacho-Ordonez Atzin Robles-Contreras +5 位作者 Oscar Guerrero-Berger Nadezhda Camacho-Ordonez Roberto Rodríguez-Rivas Laura Adalid-Peralta Amin Cervantes-Arriaga Mayela Rodríguez-Violante 《Annals of Eye Science》 2023年第4期36-47,共12页
Background:Neuroinflammation is an essential event in Parkinson’s disease(PD).Identifying affordable and less invasive biomarkers to make an early diagnosis and monitor therapeutic strategies should be a priority amo... Background:Neuroinflammation is an essential event in Parkinson’s disease(PD).Identifying affordable and less invasive biomarkers to make an early diagnosis and monitor therapeutic strategies should be a priority among researchers.The study’s objective was to measure tear levels of cytokines in subjects with PD and their association with motor features and the presence of dry eye symptoms.Methods:A total of 16 subjects with PD and 16 age-and sex-matched controls were included.Movement Disorders Society-Unified Parkinson’s Disease Rating Scale(MDS-UPDRS),Hoehn and Yahr(HY)stage scale,Montreal Cognitive Assessment(MoCA),tear break-up time(TBUT),blink rate(BR),Dry Eye Questionnaire 5(DEQ-5)were examined,and pro-inflammatory cytokines[interleukin(IL)-1β,IL-6,IL-8,IL-10,IL-12p70 and tumor necrosis factor-alpha(TNF-α)]were quantified in tears using the BD Cytometric Bead Array Human Inflammatory Cytokine Kit.Results:Higher tear TNF-αwere quantified in PD compared to controls(2.94±3.95 vs.0.33±0.49 pg/mL,P=0.008).According to DEQ-5,50.0%(n=8)of PD subjects and 12.5%(n=2)controls had dry eye disease(DED).No differences were found in cytokines concentrations between PD patients with DED compared to those without DED.IL-8 was associated with the HY stage,TBUT,DEQ-5,and a better MoCA score.A higher BR correlated moderately with a lower HY stage(r=−0.645,P=0.007),and DED patients have lower BR in PD(12.14±2.54 vs.9.0±2.06 blinks/minute,P=0.031).Conclusions:PD patients have higher levels of TNF-αin tears than age-and sex-matched HC.IL-8 in tears may be both involved in the severity of the disease and in the development of DED in PD.In addition,our findings suggest that as HY stage increases,indicating a more advanced stage,BR decreases,indicating greater motor impairment.Conversely,the presence of DED is associated with higher levels of bradykinesia in PD patients,suggesting a potential relationship between DED and motor impairment severity. 展开更多
关键词 tears pro-inflammatory cytokines dry eye disease(DED) Parkinson’s disease(PD)
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Effects of diamagnetic drift on nonlinear interaction between multi-helicity neoclassical tearing modes
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作者 王海源 姜帅 +3 位作者 刘桐 魏来 栾其斌 王正汹 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期452-458,共7页
A numerical study of the diamagnetic drift effect on the nonlinear interaction between multi-helicity neoclassical tearing modes(NTMs) is carried out using a set of four-field equations including two-fluid effects.The... A numerical study of the diamagnetic drift effect on the nonlinear interaction between multi-helicity neoclassical tearing modes(NTMs) is carried out using a set of four-field equations including two-fluid effects.The results show that,in contrast to the single-fluid case,5/3 NTM cannot be completely suppressed by 3/2 NTM with diamagnetic drift flow.Both modes exhibit oscillation and coexist in the saturated phase.To better understand the effect of the diamagnetic drift flow on multiple-helicity NTMs,the influence of typical relevant parameters is investigated.It is found that the average saturated magnetic island width increases with increasing bootstrap current fraction f_(b) but decreases with the ion skin depth δ.In addition,as the ratio of parallel to perpendicular transport coefficients χ_(‖)/χ_(⊥) increases,the average saturated magnetic island widths of the 3/2 and 5/3 NTMs increase.The underlying mechanisms behind these observations are discussed in detail. 展开更多
关键词 TOKAMAK TWO-FLUID neoclassical tearing modes multi-helicity
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Microstructure and Hot Tearing Sensitivity Simulation and Parameters Optimization for the Centrifugal Casting of Al-Cu Alloy
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作者 Xueli He Shengkun Lv +4 位作者 Ruifeng Dou Yanying Zhang Junsheng Wang Xunliang Liu Zhi Wen 《Computers, Materials & Continua》 SCIE EI 2024年第8期2873-2895,共23页
Four typical theories on the formation of thermal tears:strength,liquid film,intergranular bridging,and solidifica-tion shrinkage compensation theories.From these theories,a number of criteria have been derived for pr... Four typical theories on the formation of thermal tears:strength,liquid film,intergranular bridging,and solidifica-tion shrinkage compensation theories.From these theories,a number of criteria have been derived for predicting the formation of thermal cracks,such as the stress-based Niyama,Clyne,and RDG(Rapaz-Dreiser-Grimaud)criteria.In this paper,a mathematical model of horizontal centrifugal casting was established,and numerical simulation analysis was conducted for the centrifugal casting process of cylindrical Al-Cu alloy castings to investigate the effect of the centrifugal casting process conditions on the microstructure and hot tearing sensitivity of alloy castings by using the modified RDG hot tearing criterion.Results show that increasing the centrifugal rotation and pouring speeds can refine the microstructure of the alloy but increasing the pouring and mold preheating temperatures can lead to an increase in grain size.The grain size gradually transitions from fine grain on the outer layer to coarse grain on the inner layer.Meanwhile,combined with the modified RDG hot tearing criterion,the overall distribution of the castings’hot tearing sensitivity was analyzed.The analysis results indicate that the porosity in the middle region of the casting was large,and hot tearing defects were prone to occur.The hot tearing tendency on the inner side of the casting was greater than that on the outer side.The effects of centrifugal rotation speed,pouring temperature,and preheating temperature on the thermal sensitivity of Al-Cu alloy castings are summarized in this paper.This study revealed that the tendency of alloy hot cracking decreases with the increase of the centrifugal speed,and the maximum porosity of castings decreases first and then increases with the pouring temperature.As the preheating temperature increases,the overall maximum porosity of castings shows a decreasing trend. 展开更多
关键词 Centrifugal casting Al-Cu alloy MICROSTRUCTURE hot tearing SIMULATION
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Risk Factors Associated with Obstetric Perineal Tear in a Maternity Ward of the Communal Medical Center of Ratoma-Conakry-Guinea
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作者 Mamadou Hady Diallo Fatoumata Bamba Diallo +7 位作者 Alhassane II Sow Ibrahima Tangaly Diallo Fatoumata Kora Balde Alpha Boubacar Barry Abdourahamane Diallo Ibrahima Sory Balde Telly Sy Namory Keita 《Open Journal of Obstetrics and Gynecology》 2024年第10期1628-1639,共12页
Introduction: Obstetric perineal tears are a common complication during childbirth. The objectives of this study were to describe the sociodemographic characteristics, the different types of perineal tears and to iden... Introduction: Obstetric perineal tears are a common complication during childbirth. The objectives of this study were to describe the sociodemographic characteristics, the different types of perineal tears and to identify the associated risk factors. Patients and Method: The maternity of the CMC of Ratoma served as a setting for carrying out this study. This was a prospective study of a descriptive and analytical type, which took place over a period of 6 months from July 1, 2021 to January 1, 2022. Results: The frequency of perineal tear was 9%. The average age of the patients concerned was 23.99 years ± 5.18 years, with extremes of 15 and 38 years. Housewives were the most numerous (30.88%). Most of our parturient had undergone excision (99.6%) and they were more frequently primiparous (40.44%) and pauciparous (47.79%). The multiplicity of risk factors was a remarkable fact (scarred perineum, edematous, short, and infected). The presentation was cephalic in 96.33%, posterior variety in 3.81% and the variety of positions could not be specified by the health worker who provided care to the parturient in 46.56%. The expulsion took place in OP (92.37%) and in OS (2.30%). In most cases, midwives carried out deliveries (93%). Perineal tears were 1st degree (54.41%), 2nd degree (39.70%), 3rd degree (5.15%) and 4th degree (0.74%). Conclusion: Prevention of perineal obstetric injuries is based on better knowledge of risk factors and delivery by qualified personnel. The main limitation of this study is the impossibility of highlighting occult perineal lesions due to the weakness of the technical platform. 展开更多
关键词 Perineal tear Risk Factors Conakry
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MXenes: Versatile 2D materials with tailored surface chemistry and diverse applications
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作者 Sunil Kumar Nitu Kumari Yongho Seo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期253-293,I0008,共42页
MXenes,the most recent addition to the 2D material family,have attracted significant attention owing to their distinctive characteristics,including high surface area,conductivity,surface characteristics,mechanical str... MXenes,the most recent addition to the 2D material family,have attracted significant attention owing to their distinctive characteristics,including high surface area,conductivity,surface characteristics,mechanical strength,etc.This review begins by presenting MXenes,providing insights into their structural characteristics,synthesis methods,and surface functional groups.The review covers a thorough analysis of MXene surface properties,including surface chemistry and termination group impacts.The properties of MXenes are influenced by their synthesis,which can be fluorine-based or fluorinedependent.Fluorine-based synthesis techniques involve etching with fluorine-based reagents,mainly including HF or LiF/HCl,while fluorine-free methods include electrochemical etching,chemical vapor deposition(CVD),alkaline etching,Lewis acid-based etching,etc.These techniques result in the emergence of functional groups such as-F,-O,-OH,-Cl,etc.on the MXenes surface,depending on the synthesis method used.Properties of MXenes,such as electrical conductivity,electronic properties,catalytic activity,magnetic properties,mechanical strength,and chemical and thermal stability,are examined,and the role of functional groups in determining these properties is explored.The review delves into the diverse applications of MXenes,encompassing supercapacitors,battery materials,hydrogen storage,fuel cells,electromagnetic interference(EMI) shielding,pollutant removal,water purification,flexible electronics,sensors,additive manufacturing,catalysis,biomedical and healthcare fields,etc.Finally,this article outlines the challenges and opportunities in the current and future development of MXenes research,addressing various aspects such as synthesis scalability,etching challenges,and multifunctionality,and exploring novel applications.The review concludes with future prospects and conclusions envisioning the impact of MXenes on future technologies and innovation. 展开更多
关键词 MXenes 2D materials Surface chemistry MXenes structure SYNTHESIS APPLICATIONS
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Effects of counter-current driven by electron cyclotron waves on neoclassical tearing mode suppression
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作者 高钦 郑平卫 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期501-509,共9页
Through theoretical analysis,we construct a physical model that includes the influence of counter-external driven current opposite to the plasma current direction in the neoclassical tearing mode(NTM).The equation is ... Through theoretical analysis,we construct a physical model that includes the influence of counter-external driven current opposite to the plasma current direction in the neoclassical tearing mode(NTM).The equation is used with this model to obtain the modified Rutherford equation with co-current and counter-current contributions.Consistent with the reported experimental results,numerical simulations have shown that the localized counter external current can only partially suppress NTM when it is far from the resonant magnetic surface.Under some circumstances,the Ohkawa mechanism dominated current drive(OKCD)by electron cyclotron waves can concurrently create both co-current and counter-current.In this instance,the minimal electron cyclotron wave power that suppresses a particular NTM was calculated by the Rutherford equation.The result is marginally less than when taking co-current alone into consideration.As a result,to suppress NTM using OKCD,one only needs to align the co-current with a greater OKCD peak well with the resonant magnetic surface.The effect of its lower counter-current does not need to be considered because the location of the counter-current deviates greatly from the resonant magnetic surface. 展开更多
关键词 driven current neoclassical tearing mode modified Rutherford equation electron cyclotron waves
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Discharge plasma for prebiotic chemistry: Pathways to life’s building blocks
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作者 DingWei Gan LongFei Hong +9 位作者 TianYu Li TianQi Zhang XiangYu Wang JiePing Fan RuSen Zhou DingXin Liu JianXi Ying Patrick JCullen YuFen Zhao RenWu Zhou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期823-835,共13页
Discharge plasmas, recognized as unique platforms for investigating the origins of chemical life, have garnered extensive interest for their potential to simulate prebiotic conditions. This paper embarks on a comprehe... Discharge plasmas, recognized as unique platforms for investigating the origins of chemical life, have garnered extensive interest for their potential to simulate prebiotic conditions. This paper embarks on a comprehensive overview of recent advancements in the plasma-enabled synthesis of life’s building blocks, charting the complex environmental parameters believed to have surrounded life’s inception. This discussion elaborates on the fundamental mechanisms of discharge plasmas and their likely role in fostering conditions necessary for the origin of life on early Earth. We consider a variety of chemical reactions facilitated by plasma, specifically the synthesis of vital organic molecules - amino acids, nucleobases, sugars, and lipids. Further, we delve into the impact of plasmas on prebiotic chemical evolution. We expect this review to open new horizons for future investigations in plasma-related prebiotic chemistry that could offer valuable insights for unraveling the mysteries of life's origin. 展开更多
关键词 origin of life discharge plasma prebiotic chemistry chemical evolution
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Achieving asymmetric redox chemistry for oxygen evolution reaction through strong metal-support interactions
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作者 Shihao Wang Meiling Fan +4 位作者 Hongfei Pan Jiahui Lyu Jinsong Wu Haolin Tang Haining Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期526-535,共10页
Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redo... Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redox chemistry through elaborate surface OO–Ru–OH and bulk Ru–O–Ni/Fe coordination moieties within single-atom Ru-decorated defective NiFe LDH nanosheets(Ru@d-NiFe LDH)in conjunction with strong metal-support interactions(SMSI).Rigorous spectroscopic characterization and theoretical calculations indicate that single-atom Ru can delocalize the O 2p electrons on the surface and optimize d-electron configurations of metal atoms in bulk through SMSI.The^(18)O isotope labeling experiment based on operando differential electrochemical mass spectrometry(DEMS),chemical probe experiments,and theoretical calculations confirm the encouraged surface lattice oxygen,stabilized bulk lattice oxygen,and enhanced adsorption of oxygen-containing intermediates for bulk metals in Ru@d-NiFe LDH,leading to asymmetric redox chemistry for OER.The Ru@d-NiFe LDH electrocatalyst exhibits exceptional performance with an overpotential of 230 mV to achieve 10 mA cm^(−2)and maintains high robustness under industrial current density.This approach for achieving asymmetric redox chemistry through SMSI presents a new avenue for developing high-performance electrocatalysts and instills confidence in its industrial applicability. 展开更多
关键词 Reaction redox chemistry Strong metal-support interactions Layered double hydroxides ELECTROCATALYSTS Water electrolysis
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Why the abnormal phenomena of D-band center theory exist?A new BASED theory for surface catalysis and chemistry
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作者 Zelong Qiao Run Jiang +1 位作者 Jimmy Yun Dapeng Cao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期44-53,共10页
Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with th... Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with the continuous development of material systems and modification strategies,researchers have gradually found that D-band center theory is usually effective for large metal particle systems,but for small metal particle systems or semiconductors,such as single atom systems,the opposite conclusion to the D-band center theory is often obtained.To solve the issue above,here we propose a bonding and anti-bonding orbitals stable electron intensity difference(BASED)theory for surface chemistry.The newly-proposed BASED theory can not only successfully explain the abnormal phenomena of D-band center theory,but also exhibits a higher accuracy for prediction of adsorption energy and bond length of intermediates on active sites.Importantly,a new phenomenon of the spin transition state in the adsorption process is observed based on the BASED theory,where the active center atom usually yields an unstable high spin transition state to enhance its adsorption capability in the adsorption process of intermediates when their distance is about 2.5Å.In short,the BASED theory can be considered as a general principle to understand catalytic mechanism of intermediates on surfaces. 展开更多
关键词 Surface chemistry Surface catalysis D-band center theory Bonding orbital Anti-bonding orbital
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Teaching Status and Teaching Reform Ideas of Physical Chemistry Experiments for Food Quality and Safety Major
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作者 Bo HOU Jing LIAO 《Agricultural Biotechnology》 2024年第3期45-47,54,共4页
Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the ... Physical chemistry experiments are an important branch of chemical experiments.In view of problems and shortcomings in physical chemistry experiment teaching of food quality and safety major in Chengdu University,the teaching methods of physical chemistry experiment course of food quality and safety major were explored and practiced,aiming to arouse students enthusiasm for experiments and cultivate their ability of independent learning,comprehensive thinking and independent problem solving. 展开更多
关键词 Physical chemistry experiment Food quality SAFETY
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The Prevalence Type of the Meniscus Tear in Patients with Anterior Cruciate Ligament (ACL) Injury, in Abu Arish General Hospital, Jazan, KSA
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作者 Eissa Gobran A. Bakri 《Open Journal of Applied Sciences》 2024年第7期1625-1636,共12页
Background: The anterior cruciate ligament (ACL) is the main structure that prevents the forward movement of the tibia about the femur Meniscus tear which is a common finding in patients with anterior cruciate ligamen... Background: The anterior cruciate ligament (ACL) is the main structure that prevents the forward movement of the tibia about the femur Meniscus tear which is a common finding in patients with anterior cruciate ligament (ACL) injury. Aim: To investigate the prevalence of types of meniscus tears in patients with Anterior Cruciate Ligament (ACL) Injury. Methods: A retrospective study was conducted among inpatients. Clinical evaluation included side-to-side difference in anterior tibial translation (ATT) as measured by a KT-1000 arthrometer (MEDmetric Corp) and a grade of pivot-shift test at final follow-up in all patients. Subsequent meniscal tear was defined by symptoms of joint line pain and/or locking or joint effusion requiring surgical treatment. Results: Most of patients were males (92.6%). The patients were categorized into 5 groups according to age with a mean of age 32.8 ± 10.6. The most common causes of ACL injury were falling down (43.2%), trauma (38.1%) or knee torsion (18.8%). Medial meniscal tear was found in 92 knees (55.7%), while lateral meniscal tear was found in 19 knees (10.8%) and the most common type was the longitudinal tear that was found in 31 knees (17.6%). Similarly, 66.7% of the meniscal flap tears and half of the meniscal bucket-handle tears were significantly associated with loose body (P Conclusion: The present study demonstrated that meniscus tears are more common in individuals with chronic ACL rupture. The main factors contributing to ACL injury were classified as falls, trauma, and knee torsion. Gender was identified as a critical determinant in the etiology of ACL injury. The occurrence of a ramp lesion was associated longitudinal meniscal tears, whereas chodoral injury was associated with the majority of meniscal flap tears and meniscal bucket-handle tears. 展开更多
关键词 PREVALENCE TYPE MENISCUS tear Anterior Cruciate Ligament ACL INJURY
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Designing ultrastable P2/O3-type layered oxides for sodium ion batteries by regulating Na distribution and oxygen redox chemistry
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作者 Jieyou Huang Weiliang Li +3 位作者 Debin Ye Lin Xu Wenwei Wu Xuehang Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期466-476,共11页
P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phas... P2/O3-type Ni/Mn-based layered oxides are promising cathode materials for sodium-ion batteries(SIBs)owing to their high energy density.However,exploring effective ways to enhance the synergy between the P2 and 03 phases remains a necessity.Herein,we design a P2/O3-type Na_(0.76)Ni_(0.31)Zn_(0.07)Mn_(0.50)Ti_(0.12)0_(2)(NNZMT)with high chemical/electrochemical stability by enhancing the coupling between the two phases.For the first time,a unique Na*extraction is observed from a Na-rich O3 phase by a Na-poor P2 phase and systematically investigated.This process is facilitated by Zn^(2+)/Ti^(4+)dual doping and calcination condition regulation,allowing a higher Na*content in the P2 phase with larger Na^(+)transport channels and enhancing Na transport kinetics.Because of reduced Na^(+)in the O3 phase,which increases the difficulty of H^(+)/Na^(+) exchange,the hydrostability of the O3 phase in NNZMT is considerably improved.Furthermore,Zn^(2+)/Ti^(4+)presence in NNZMT synergistically regulates oxygen redox chemistry,which effectively suppresses O_(2)/CO_(2) gas release and electrolyte decomposition,and completely inhibits phase transitions above 4.0 V.As a result,NNZMT achieves a high discharge capacity of 144.8 mA h g^(-1) with a median voltage of 3.42 V at 20 mA g^(-1) and exhibits excellent cycling performance with a capacity retention of 77.3% for 1000 cycles at 2000 mA g^(-1).This study provides an effective strategy and new insights into the design of high-performance layered-oxide cathode materials with enhanced structure/interface stability forSIBs. 展开更多
关键词 Sodium-ion batteries P2/O3-type layered oxides Na distribution Oxygen redox chemistry Hydrostability
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Exploration of Ideological and Political Materials for the Course of Inorganic and Analytical Chemistry for Environmental and Ecological Engineering Major
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作者 Lihua XIE Siqian JIAO +4 位作者 Pengqiang YAO Weishuang TONG Yanjiao LI Zhe WANG Haina SONG 《Asian Agricultural Research》 2024年第4期41-47,共7页
Integrating ideological and political theories teaching into the whole process of classroom teaching construction is a new requirement for implementing the fundamental task of cultivating people by virtue and playing ... Integrating ideological and political theories teaching into the whole process of classroom teaching construction is a new requirement for implementing the fundamental task of cultivating people by virtue and playing the role of collaborative education.In order to realize the seamless integration of inorganic and analytical chemistry courses and ideological and political education,this paper summarizes the current situation of ideological and political research on inorganic and analytical chemistry courses in three major databases in China(VIP,CNKI and Wanfang),and sorts out the knowledge points,ideological and political elements and educational goals according to the content of the course chapters,to provide a basic guarantee for the ideological and political education construction of the course. 展开更多
关键词 ENVIRONMENTAL and ECOLOGICAL engineering Ideological and POLITICAL MATERIALS TALENT training INORGANIC and analytical chemistry
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