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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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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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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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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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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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Dynamic tear meniscus parameters in complete blinking:insights into dry eye assessment 被引量:1
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作者 Ying-Huai Zhang Jun Feng +4 位作者 Chen-Yuan Yi Xian-Yu Deng Yong-Jin Zhou Lei Tian Ying Jie 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第12期1911-1918,共8页
AIM:To investigate the relationship between dynamic tear meniscus parameters and dry eye using an automated tear meniscus segmentation method.METHODS:The analysis of tear meniscus videos captured within 5s after a com... AIM:To investigate the relationship between dynamic tear meniscus parameters and dry eye using an automated tear meniscus segmentation method.METHODS:The analysis of tear meniscus videos captured within 5s after a complete blink includes data from 38 participates.By processing video data,several key parameters including the average height of the tear meniscus at different lengths,the curvature of the tear meniscus’s upper boundary,and the total area of the tear meniscus in each frame were calculated.The effective values of these dynamic parameters were then linearly fitted to explore the relationship between their changing trends and dry eye disease.RESULTS:In 94.74%of the samples,the average height of central tear meniscus increased over time.Moreover,97.37%of the samples exhibited an increase in the overall tear meniscus height(TMH)and area from the nasal to temporal side.Notably,the central TMH increased at a faster rate compared to the nasal side with the temporal side showing the slowest ascent.Statistical analysis indicates that the upper boundary curvature of the whole tear meniscus as well as the tear meniscus of the nasal side(2,3,and 4 mm)aid in identifying the presence of dry eye and assessing its severity.CONCLUSION:This study contributes to the understanding of tear meniscus dynamics as potential markers for dry eye,utilizing an automated and non-invasive approach that has implications for clinical assessment. 展开更多
关键词 dry eye DYNAMIC tear meniscus BLINKING
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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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Effect of addition of minor amounts of Sb and Gd on hot tearing susceptibility of Mg-5Al-3Ca alloy 被引量:1
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作者 Xudong Du Feng Wang +3 位作者 Zhi Wang Le Zhou Zheng Liu Pingli Mao 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第2期694-705,共12页
The effects of addition of minor amount of(0.5 wt.%) antimony(Sb) or gadolinium(Gd) and combined addition of Sb and Gd(0.5 wt.%,respectively) on the hot tearing susceptibility(HTS) of Mg-5Al-3Ca alloy were investigate... The effects of addition of minor amount of(0.5 wt.%) antimony(Sb) or gadolinium(Gd) and combined addition of Sb and Gd(0.5 wt.%,respectively) on the hot tearing susceptibility(HTS) of Mg-5Al-3Ca alloy were investigated experimentally using a “T-shaped” hot tearing measuring system. Various solidification parameters of the alloys were measured and calculated through thermal analysis experiments. The microstructure, grain size, and morphology of the crack zone were characterized by scanning electron microscopy and electron backscatter diffraction, and the crystal phases of the alloys were analyzed by X-ray diffraction and energy-dispersive X-ray spectroscopy. The results showed that the addition of 0.5 wt.% Gd resulted in the increase in the vulnerable temperature range(Tv) and reduced the eutectic structure content that could participate in feeding, thereby improving the HTS of the alloy. However, addition of 0.5 wt.% Sb or combined addition of Gd and Sb(0.5 wt.%, respectively) to the Mg-5Al-3Ca alloy shortened the Tvand improved the skeleton strength of the alloy, thereby reducing HTS. Moreover, significantly refined structure of Mg-5Al-3Ca-0.5Gd-0.5Sb alloy improved the feeding ability of the eutectic structure, thus the alloy exhibited the lowest HTS. 展开更多
关键词 Hot tearing susceptibility Mg-5Al-3Ca alloy Thermal analysis Microstructure
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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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ANovel Light Weight CNN Framework Integrated with Marine Predator Optimization for the Assessment of Tear Film-Lipid Layer Patterns
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作者 Bejoy Abraham Jesna Mohan +1 位作者 Linu Shine Sivakumar Ramachandran 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期87-106,共20页
Tear film,the outermost layer of the eye,is a complex and dynamic structure responsible for tear production.The tear film lipid layer is a vital component of the tear film that provides a smooth optical surface for th... Tear film,the outermost layer of the eye,is a complex and dynamic structure responsible for tear production.The tear film lipid layer is a vital component of the tear film that provides a smooth optical surface for the cornea and wetting the ocular surface.Dry eye syndrome(DES)is a symptomatic disease caused by reduced tear production,poor tear quality,or excessive evaporation.Its diagnosis is a difficult task due to its multifactorial etiology.Out of several clinical tests available,the evaluation of the interference patterns of the tear film lipid layer forms a potential tool for DES diagnosis.An instrument known as Tearscope Plus allows the rapid assessment of the lipid layer.A grading scale composed of five categories is used to classify lipid layer patterns.The reported work proposes the design of an automatic system employing light weight convolutional neural networks(CNN)and nature inspired optimization techniques to assess the tear film lipid layer patterns by interpreting the images acquired with the Tearscope Plus.The designed framework achieves promising results compared with the existing state-of-the-art techniques. 展开更多
关键词 Dry-eye syndrome tearscope plus tear film deep neural networks
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Effects of plasma radiation on the nonlinear evolution of neo-classical tearing modes in tokamak plasmas with reversed magnetic shear
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作者 姜帅 王正汹 +1 位作者 魏来 刘桐 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期548-555,共8页
Effects of plasma radiation on the nonlinear evolution of neo-classical double tearing modes(NDTMs)in tokamak plasmas with reversed magnetic shear are numerically investigated based on a set of reduced magnetohydrodyn... Effects of plasma radiation on the nonlinear evolution of neo-classical double tearing modes(NDTMs)in tokamak plasmas with reversed magnetic shear are numerically investigated based on a set of reduced magnetohydrodynamics(MHD)equations.Cases with different separations △_(rs)=|r_(s2)-r_(s1)|between the two same rational surfaces are considered.In the small △_(rs)cases,the plasma radiation destabilizes the NDTMs and makes the kinetic energy still grow gradually in the late nonlinear phase.Moreover,the NDTM harmonics with high mode numbers reach a high level in the presence of plasma radiation,forming a broad spectrum of MHD perturbations that induces a radially broadened region of MHD turbulence.As a result,the profiles of safety factors also enter a nonlinear oscillation phase.In the intermediate △_(rs)case,the plasma radiation can advance the explosive burst of kinetic energy that results from the fast driven reconnection between the two rational surfaces,because it can further promote the destabilizing effects of bootstrap current perturbation on the magnetic island near the outer rational surfaces.In the large △_(rs)case,through destabilizing the outer islands significantly,the plasma radiation can even induce the explosive burst in the reversed magnetic shear configuration where the burst cannot be induced in the absence of plasma radiation. 展开更多
关键词 neoclassical tearing mode MAGNETOHYDRODYNAMICS nonlinear phenomena
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An Improved Transosseous Pullout Suture Technique for Arthroscopic Repair of a Meniscus Root Tear
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作者 Wen-bin ZHAO Feng TU Hao WANG 《Current Medical Science》 SCIE CAS 2023年第4期779-783,共5页
Objective:This study aimed to explore the clinical efficiency of an improved transosseous pullout suture technique for arthroscopic repair of a meniscus root tear.Methods:From January 2017 to January 2021,53 patients ... Objective:This study aimed to explore the clinical efficiency of an improved transosseous pullout suture technique for arthroscopic repair of a meniscus root tear.Methods:From January 2017 to January 2021,53 patients with posterior meniscus root tears combined with anterior cruciate ligament(ACL)and/or posterior cruciate ligament(PCL)tears were collected.Totally,in 29 patients(group A),the 2.0 mm modified pullout tunnel method was used to suture the posterior meniscus root,while 24 patients(group B)were treated with the traditional 4.5 mm pullout tunnel method.In group A,20 patients had lateral meniscus posterior root(LMPR)combined with ACL tears,5 patients had LMPR combined with ACL and PCL tears,and 4 patients had medial meniscus posterior root(MMPR)combined with ACL tears.In group B,19 patients had LMPR combined with ACL tears,3 patients had LMPR combined with ACL and PCL tears,and 2 patients had MMPR combined with ACL tears.The improvement of the Lysholm and VAS scores and the incidence of complications in group A and group B before the operation,1 month and 3 months after the operation,and after the final follow-up were compared.Results:Preoperative Lysholm score was 26.0±5.6 in group A and 26.7±5.8 in group B(P>0.05).One-month postoperative Lysholm score was 66.5±5.7 in group A and 54.3±2.4 in group B(P<0.001).Three-month postoperative Lysholm score was 81.1±7.2 in group A and 73.2±9.7 in group B(P<0.05).Lysholm scores after the final follow-up was 90.3±5.6 in group A and 90.0±5.0 in group B(P>0.05).Preoperative VAS score was 6.3±1.4 in group A and 6.3±1.2 in group B(P>0.05).One-month postoperative VAS score was 1.8±0.7 in group A and 2.4±0.9 in group B(P<0.05).Three-month postoperative VAS score was 0.7±0.6 in group A and 0.8±0.6 in group B(P>0.05).VAS score after the final follow-up was 0.2±0.4 in group A and 0.3±0.5 in group B(P>0.05).Conclusion:The improved transosseous pullout suture technique using a smaller 2.0 mm bone tunnel can virtually eliminate the risk of conflict with other bone tunnels and facilitate the management of bone tunnels in multiple ligament injuries,while also diminishing suture abrasion caused by the windshield wiper effect.The technique achieves good clinical efficacy. 展开更多
关键词 meniscus root tear bone tunnel multiple ligament injury tunnel management windshield wiper effect
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Role of lymphotoxin alpha as a new molecular biomarker in revolutionizing tear diagnostic testing for dry eye disease
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作者 Chao-Ran Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第11期1883-1889,共7页
Dry eye disease(DED),primarily classified as multifactorial ocular surface disorder,afflicts tens of millions of individuals worldwide,adversely impacting their quality of life.Extensive research has been conducted on... Dry eye disease(DED),primarily classified as multifactorial ocular surface disorder,afflicts tens of millions of individuals worldwide,adversely impacting their quality of life.Extensive research has been conducted on tear film analysis over the past decades,offering a range of tests to evaluate its volume,health,and integrity.Yet,early diagnosis and effective treatment for DED continue to pose significant challenges in clinical settings.Nevertheless,by recognizing key phenomena in DED such as ocular surface inflammation,hyperosmolarity,and tear film instability,this article provides a comprehensive overview of both traditional and recently developed methods for diagnosing and monitoring DED.The information serves as a valuable resource not only for clinical diagnosis but also for further research into DED. 展开更多
关键词 dry eye disease tear film BIOMARKER matrix metalloproteinase 9 lymphotoxin alpha
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Validation of the current and pressure coupling schemes with nonlinear simulations of TAE and analysis on the linear stability of tearing mode in the presence of energetic particles
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作者 张豪伟 马志为 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第4期39-50,共12页
Both current and pressure coupling schemes have been adopted in the hybrid kinetic–magnetohydrodynamic code CLT-K recently.Numerical equivalences between these two coupling schemes are strictly verified under differe... Both current and pressure coupling schemes have been adopted in the hybrid kinetic–magnetohydrodynamic code CLT-K recently.Numerical equivalences between these two coupling schemes are strictly verified under different approximations.First,when considering only the perturbed distribution function of energetic particles(EPs),the equivalence can be proved analytically.Second,when both the variations of the magnetic field and the EP distribution function are included,the current and pressure coupling schemes numerically produce the same result in the nonlinear simulations.On this basis,the influences of co-/counter-passing and trapped EPs on the linear stabilities of the m/n=2/1 tearing mode(TM)have been investigated(where m and n represent the poloidal and toroidal mode numbers,respectively).The results of scanningβh of EPs show that the co-passing and trapped EPs are found to stabilize the TM,while the counter-passing EPs tend to destabilize the TM.The behind(de)stabilization mechanisms of the TM by EPs are carefully analyzed.Furthermore,after exceeding critical EP betas,the same branch of the high-frequency mode is excited by co-/counterpassing and trapped EPs,which is identified as the m/n=2/1 energetic particle mode. 展开更多
关键词 hybrid kinetic–magnetohydrodynamic simulation tearing mode energetic particle
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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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Tear inflammation related indexes after cataract surgery in elderly patients with type 2 diabetes mellitus
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作者 Jun Lv Cheng-Jian Cao +3 位作者 Wei Li Shuang-Le Li Jun Zheng Xiu-Li Yang 《World Journal of Clinical Cases》 SCIE 2023年第2期385-393,共9页
BACKGROUND Quantitative studies on the changes in inflammation-related content in tears,especially the effect of diabetes,are lacking.In this study,we measured the preoperative and postoperative tear inflammatory medi... BACKGROUND Quantitative studies on the changes in inflammation-related content in tears,especially the effect of diabetes,are lacking.In this study,we measured the preoperative and postoperative tear inflammatory mediator levels in cataract patients,focusing on the expression of inflammatory factors in postoperative cataracts in the diabetic,and investigated the effect of drugs on the control of postoperative inflammation.AIM To study the expression of inflammatory factors in elderly people with type 2 diabetes after cataract surgery.METHODS Patients with a mean age of 70.3±6.3 years were divided into group A(composed of elderly patients with cataracts and type 2 diabetes,n=20 eyes)and group B(patients with age-related cataract,n=20 eyes).Their tears were collected before each operation and on days 1 and 3,and weeks 1,2,3,and 4 post-surgery.Saline(150μL)was dropped into the conjunctival sac of the surgical eye,followed by oculogyration in four directions.The fluid in the conjunctival sac was extracted using a sterile syringe and stored in Eppendorf tubes at-80°C until measurement.The expression levels of matrix metalloproteinase-2(MMP-2),MMP-9,tissue inhibitor of metalloproteinase-1(TIMP-1),TIMP-2,interleukin-6(IL-6),and IL-20 in tear fluid were measured using enzyme-linked immunosorbent assays.RESULTS The postoperative expression levels of MMP-2,MMP-9,TIMP-2,IL-6,and IL-20 in group A were significantly higher than those in group B,whereas the concentration of TIMP-1 in group A remained lower than that in group B.The levels of MMP-2 and IL-6 in both groups continuously increased until the peak in the first postoperative week,and then gradually decreased over the next three weeks.Ultimately,MMP-2 declined to a lower level than that preoperatively at week 4,but IL-6 decreased to the same level as that preoperatively.The level of MMP-9 peaked in the first two weeks postoperative and then returned to the same level as 1-day post-operation.The concentration of TIMP-1 post-operation remained constant at a lower level than before surgery,and TIMP-2 Levels remained stable in both groups.IL-20 content started to increase in the third week after surgery.CONCLUSION Inflammatory factor levels in tears fluctuated before and post-operation,which indicated more severe postoperative inflammation in the first two weeks. 展开更多
关键词 Type 2 diabetes mellitus Elderly patients Cataract surgery tear inflammation-related indicators Temporal changes Prognosis
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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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热轧含钛低合金高强钢板断口分层机理研究 被引量:2
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作者 董欣欣 杨丽 +2 位作者 唐勤 张丽颖 杨建辉 《有色金属科学与工程》 CAS 北大核心 2024年第1期51-57,共7页
利用光学显微镜(OM)、电子背散射衍射仪(EBSD)、透射电镜(TEM)等设备研究了含钛低合金高强钢拉伸断口分层原因。结果显示:在显微组织和晶粒尺寸正常的情况下,MnS和大颗粒Ti(C,N)夹杂物聚集是导致断口分层的根本原因。拉伸断口呈现撕裂棱... 利用光学显微镜(OM)、电子背散射衍射仪(EBSD)、透射电镜(TEM)等设备研究了含钛低合金高强钢拉伸断口分层原因。结果显示:在显微组织和晶粒尺寸正常的情况下,MnS和大颗粒Ti(C,N)夹杂物聚集是导致断口分层的根本原因。拉伸断口呈现撕裂棱+浅韧窝的准解理形貌。塑性变形过程中,Ti(C,N)破碎导致显微裂纹萌生。裂纹沿着薄膜状MnS传导,最终在MnS和基体界面形成撕裂棱。大量平行分布的MnS夹杂物共同作用,使断口产生分层现象。通过降低S、N含量能够有效减少两类夹杂物数量,消除断口分层现象,改善塑性指标。 展开更多
关键词 显微组织 拉伸断口 撕裂棱 准解理 夹杂物
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