Expert consensus on difficulty assessment of endodontic therapy

Endodontic diseases are a kind of chronic infectious oral disease. Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha. However, it is very essential for endodontic treatment to debride the root canal system and prevent the root canal system from bacterial reinfection after root canal therapy(RCT). Recent research, encompassing bacterial etiology and advanced imaging techniques, contributes to our understanding of the root canal system’s anatomy intricacies and the technique sensitivity of RCT. Success in RCT hinges on factors like patients, infection severity, root canal anatomy, and treatment techniques. Therefore, improving disease management is a key issue to combat endodontic diseases and cure periapical lesions. The clinical difficulty assessment system of RCT is established based on patient conditions, tooth conditions, root canal configuration, and root canal needing retreatment, and emphasizes pre-treatment risk assessment for optimal outcomes. The findings suggest that the presence of risk factors may correlate with the challenge of achieving the high standard required for RCT. These insights contribute not only to improve education but also aid practitioners in treatment planning and referral decision-making within the field of endodontics.

Transfer learning-based super-resolution in panoramic models for predicting mandibular third molar extraction difficulty: a multi-center study

Background:This study aims to predict the extraction difficulty of mandibular third molars based on panoramic images using transfer learning while employing super-resolution(SR)technology to enhance the feasibility and validity of the prediction.Methods:We reviewed a total of 608 preoperative mandibular third molar panoramic radiographs from two medical facilities:the First Affiliated Hospital of Zhengzhou University(n=509;456 in the training set and 53 in the test set)and the Henan Provincial Dental Hospital(n=99 in the validation set).We conducted a deep-transfer learning network on high-resolution(HR)panoramic radiographs to improve the longitudinal resolution of the images and obtained the SR images.Subsequently,we constructed models named Model-HR and Model-SR using high-dimensional quantitative features extracted through the Least Absolute Shrinkage and Selection Operator method.The models’performances were evaluated using the receiver operating characteristic curve(ROC).To assess the reliability of the model,we compared the results from the test set with those of three dentists.Results:Model-SR outperformed Model-HR(area under the curve(AUC):0.779,sensitivity:85.5%,specificity:60.9%,and accuracy:79.8%vs.AUC:0.753,sensitivity:73.7%,specificity:73.9%,and accuracy:73.7%)in predicting the difficulty of extracting mandibular third molars.Both Model-HR(AUC=0.821,95%CI 0.687–0.956)and Model-SR(AUC=0.963,95%CI 0.921–0.999)demonstrated superior performance compared to expert dentists(highest AUC=0.799,95%CI 0.671–0.927).Conclusions:Model-SR yielded superior predictive performance in determining the difficulty of extracting mandibular third molars when compared with Model-HR and expert dentists’visual assessments.

The Effect of Topic Familiarity and Linguistic Difficulty on EFL Listening Comprehension

As a highly integrative and demanding receptive skill,listening comprehension presents a challenge to both learners and researchers.The study reported in this paper is listening comprehension objective-factor research.Manipulating topic factors,the study investigated the effect of topic familiarity and linguistic difficulty on EFL(English as a foreign language)listening comprehension of learners at different proficiency levels.

Analysis of drilling difficulty of extended-reach wells based on drilling limit theory

With the continuous increase in vertical depths and horizontal displacements of directional wells,the difficulties of drilling operations continue to increase,and more accurate methods of drilling difficulty evaluation are needed.In this paper,a drilling difficulty evaluation method is built by combining drilling limit model and expert evaluation.Firstly,the concept of drilling difficulty index is introduced,and the method to calculate drilling difficulty index is established.Next,the meanings of five drilling difficulty levels are explained and the optimization design method with drilling difficulty as the target is built.At last,the theoretical model is applied to the extended-reach drilling of the Liuhua oilfield in the South China Sea,in which drilling difficulties are evaluated and the relationship between drilling difficulty and development control radius is revealed.The results indicate that extended-reach drilling in the Liuhua oilfield is on the“normal”difficulty level on average,rotary drilling in 8_(1/2)-in.section is the most difficult,and the main constraint conditions are excessive torque and high friction.Through technology upgradation,the drilling difficulties are decreased,the development control radius increases from 6.6 to 11.4 km,and the maximum horizontalto-vertical ratio increases from 5.3 to 8.7.Then,the development wells in marginal oilfields and adjustment wells in old oilfields can be drilled on“normal”difficulty level.Therefore,technology upgradation,especially drilling rig upgradation,is the most important development direction for extended-reach drilling in the South China Sea.

Effect of rehabilitation education on pain, knee stiffness and performance difficulty in patients undergoing knee replacement surgery: A randomized clinical trial

Objective:To determine the effect of rehabilitation education on pain,knee stiffness and performance difficulty in patients undergoing knee replacement surgery.Methods:This randomized clinical trial study was performed on 96 patients undergoing knee replacement surgery,who were randomly divided into two groups:the control group and the intervention group,with 48 patients in each group.In the intervention group,the patients received educational intervention in four stages one day before surgery,24 h and 48 h later,upon discharge from the hospital.In the control group,only the routine of the hospital was performed.Questionnaires were completed before and 6 weeks after the intervention.Results:The mean scores of pain,knee stiffness and performance difficulty were significantly decreased in the intervention group(P=0.01).Compared to the control group,the intervention group had a better outcome of the illness,including pain,knee stiffness and performance difficulty(P=0.001).Conclusion:Rehabilitation education could be a suitable way to improve the surgical outcomes of patients undergoing total knee replacement.

Rxamining the relationships between medical students'preferred online instructional strategies,course difficulty level,learning performance and effectiveness

Students'preferences and engagement with online educational resources and activities are crucial for academic success in the context of online medical education.This study investigated the preferences of Chinese medical students regarding the teaching strategies used by instructors and their relationship with course difficulty level,students'academic performance and perceived effectiveness.Survey data(n=375)was collected from the medical students from one of the largest medical schools in Southern China during the spring semester of 2020.

A Note on the Validity of the Shannon Formulation for Fitts’ Index of Difficulty

The three most common variations of Fitts’ index of difficulty are the Fitts formulation, the Welford formulation, and the Shannon formulation. A recent paper by Hoffmann [1] critiqued the three and concluded that the Fitts and Welford formulations are valid and that the Shannon formulation is invalid. In this paper, we challenge Hoffmann’s position regarding the Shannon formulation. It is argued that the issue of validity vs. invalidity is ill-conceived, given that Fitts’ law is a “model by analogy” with no basis in human motor control. The relevant questions are of utility: Does a model work? How well? Is it useful? Where alternative formulations exist, they may be critiqued and compared for strengths and weaknesses, but validity is an irrelevant construct. In a reanalysis of data from Fitts’ law experiments, models built using the Shannon formulation are (re)affirmed to be as good as, and generally better than, those built using the Fitts or Welford formulation.

Sensitivity Analysis on the Negative Degree of Difficulty Geometric Programming Problem

The range of optimal values in cost optimization models provides management with options for decision making. However, it can be quite challenging to achieve feasible range of optimality in Geometric programming (Gp) models having negative degrees of difficulty. In this paper, we conduct sensitivity analysis on the optimal solution of Geometric programming problem with negative degree of difficulty. Using imprest data, we determine the optimal objective function, dual decision variables, primal decision variables;the range of values, the cost coefficient and RHS constraint must lie for the solution to stay optimal. From the analysis, we established that incremental sensitivity analysis has the functional form .

The Reasons of Students’ Difficulty in Improving Their Listening in China

With the promoting of world integration,the role of English listening and speaking is becoming more and more important.English listening is attached more importance to in higher education.Although many universities and college students take different measures to improve the students’English listening abilities,it is found that it is difficult to improve the students’English listening abilities effectively.This article will analyze the reasons of students’difficulty in improving their listening in the aim at discussing the measures to improve the students’listening effectively with other educators.

Prof.Larry Benowitz:the future of optic nerve regeneration and the difficulty of keeping retinal ganglion cells alive

Editor’s note Guangzhou Glaucoma Forum(GZGF)was successfully held in the Zhongshan Ophthalmology Center on April 21-22,2018.The forum gathered domestic and international experts from all over the world,including Prof.Larry Benowitz from Harvard Medical School,Prof.Leopold Schmetterer from Singapore Eye Research Institute,Prof.Anuj Chauhan from University of Florida,Prof.Shlomo Melamed from Israel,and Prof.Keith Barton from Moorfields Eye Hospital.AME editorial team had the honor to interview Prof.Benowitz.

Influencing program satisfaction for undergraduate students in STEM areas:The impact of interdisciplinary features,disciplinary connectedness,faculty support,and examination difficulty

Ensuring program satisfaction for undergraduate students in the areas of science,technology,engineering and mathematics(STEM)matters in student retention and education quality improvement.This study explores how four rarely examined variables support from faculty members,interdisciplinary features of STEM program courses,disciplinary connectedness of STEM program core courses,and examination difficulty impact Chinese STEM undergraduates’program satisfaction.With data from 619 Chinese STEM undergraduates,structural equation modeling shows that course satisfaction partially mediates the impact of support from faculty members on program satisfaction,while fully mediating that of interdisciplinary features of STEM program courses and disciplinary connectedness of STEM program core courses on program satisfaction.Examination difficulty exerts no significant impact on program satisfaction neither directly nor indirectly.Support from faculty members impact course satisfaction significantly stronger for junior and senior students than for freshmen and sophomores,while interdisciplinary features of STEM program courses impact course satisfaction stronger for freshmen and sophomores than for juniors and seniors.The study ends with practical implications for the higher education reform in relevant areas.

The Influence of “Pygmalion Effect” on the Junior School Students Who Have Difficulty Learning English

Pygmalion Effect refers to the expectation from teachers have stimulative effects on students' learning. English educa-tion of junior middle school has its unique nature, and the phenomenon of having trouble in learning English in middle school stu-dents exists generally. So, the key point of this research is how the students use Pygmalion Effect to improve their English Learn-ing.

Text Difficulty Study:Do Machines Behave the Same as Humans Regarding Text Difficulty?

With the emergence of pre-trained models,current neural networks are able to give task performance that is comparable to humans.However,we know little about the fundamental working mechanism of pre-trained models in which we do not know how they approach such performance and how the task is solved by the model.For example,given a task,human learns from easy to hard,whereas the model learns randomly.Undeniably,difficulty-insensitive learning leads to great success in natural language processing(NLP),but little attention has been paid to the effect of text difficulty in NLP.We propose a human learning matching index(HLM Index)to investigate the effect of text difficulty.Experiment results show:1)LSTM gives more human-like learning behavior than BERT.Additionally,UID-SuperLinear gives the best evaluation of text difficulty among four text difficulty criteria.Among nine tasks,some tasks’performance is related to text difficulty,whereas others are not.2)Model trained on easy data performs best in both easy and medium test data,whereas trained on hard data only performs well on hard test data.3)Train the model from easy to hard,leading to quicker convergence.

Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer

BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic cavities.Therefore,it is essential for colorectal surgeons to have a comprehensive understanding of pelvic structure prior to surgery and anticipate potential surgical difficulties.AIM To evaluate predictive parameters for technical challenges encountered during laparoscopic radical sphincter-preserving surgery for rectal cancer.METHODS We retrospectively gathered data from 162 consecutive patients who underwent laparoscopic radical sphincterpreserving surgery for rectal cancer.Three-dimensional reconstruction of pelvic bone and soft tissue parameters was conducted using computed tomography(CT)scans.Operative difficulty was categorized as either high or low,and multivariate logistic regression analysis was employed to identify predictors of operative difficulty,ultimately creating a nomogram.RESULTS Out of 162 patients,21(13.0%)were classified in the high surgical difficulty group,while 141(87.0%)were in the low surgical difficulty group.Multivariate logistic regression analysis showed that the surgical approach using laparoscopic intersphincteric dissection,intraoperative preventive ostomy,and the sacrococcygeal distance were independent risk factors for highly difficult laparoscopic radical sphincter-sparing surgery for rectal cancer(P<0.05).Conversely,the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance was identified as a protective factor(P<0.05).A nomogram was subsequently constructed,demonstrating good predictive accuracy(C-index=0.834).CONCLUSION The surgical approach,intraoperative preventive ostomy,the sacrococcygeal distance,and the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance could help to predict the difficulty of laparoscopic radical sphincter-preserving surgery.

Type 2 Diabetes—Hard to Select a Healthy Choice

Introduction: The use of foods containing high levels of sugar is increasing all the time. This is a risk factor for increased incidence of type 2 diabetes. There are few studies that have investigated the availability of low-sugar müsli products in grocery stores. Purpose: The study aims to identify which types of müsli contain high respectively low levels of sugar, and which brands are involved. Methods: The material consists of both qualitative interviews and observations from five grocery stores: City Gross, Hemköp, Ica Maxi, Stora Coop and Willy’s in Helsingborg, Sweden. The qualitative interviews had a semi-structured character and were recorded. The interviews took approx. 20 minutes and a textual analysis was conducted of the results. Data from observation was analyzed based on brand, nutritional composition and flavors, and also, where low sugar products were placed on store shelves. Results: The grocery stores provided together brands from AXA, Coop, Finax, Frebaco, Garant, ICA, Risenta, Saltå Kvarn och Urtekram, in total 24 müsli products. Of these products, 19 were high in sugar. The observation reveals that müsli products with high sugar content (17 - 29 g per 100 g müsli) are more prominently displayed than those with low sugar content. From the interviews with the store managers, it became clear that it would be valuable to highlight healthy müsli products on the shelves. However, central bureaucracy puts obstacles to such measures. Discussion: The study emphasizes the need for increased visibility of low-sugar products and proposes solutions such as negotiating with responsible person at the head office in Stockholm. Several reviews have shown that if the grocery store raises the prices of unhealthy food, the consumer is willing to purchase healthier müsli and other products. Conclusion: This study shows the need for grocery stores to upgrade healthy müsli products along with advertising to be able to influence customer’s shopping habits. Also, further research is needed how type 2 diabetes is affected by high intakes of food products with high sugar content.

Ableism and (Neo)Racism in School Placement Processes in Quebec: School Personnel Interpretations of Immigrant Student Difficulties - A Secondary Publication

The school placement processes of students from immigrant backgrounds considered to be in“difficulty”is an international concern at the intersection of works relating to special education and those concerning the school experiences of students from immigrant backgrounds or racialized groups.The research problem of this article concerns the identification of these students as disabled or as having adjustment or learning difficulties.From a perspective anchored in Disability Critical Race Studies,this ethnographic study documents different interpretations of perceived difficulties made by school actors with regard to seven primary school students from immigrant backgrounds.Five interpretation types are presented:(1)medicalization by dismissal of cultural markers,(2)medicalization by professional constraint,(3)medicalization by cultural deficit,(4)precautionary wait,and(5)cultural differentialism.Our results help to shed light on the special education overrepresentation phenomenon regarding these students and to understand how ableism and(neo)racism contribute to it.

Gifted Students’Special Educational Programs in France:An Analysis of Students’Needs as Perceived by Headmasters-A Secondary Publication

Some French public middle schools offer gifted students the opportunity to pursue their education in general classes,while benefiting from specific facilities within the framework of a dedicated educational program.In this study,we sought to identify and analyze the needs of these students as perceived by the headmaster of each middle school involved.The results highlight two main student needs,common to all these programs(uneasiness and difficulties in peer relationships)as well as needs specifically mentioned by some headmasters(non-adaptive behavior).

语言学习

激活·素养解读English learning methods英语学习方法1 Learning a foreign language is a challenge to us.Like lots of English learners,we have met with a variety of difficulties in learning English well.Words learning may be the first difficulty as it is hard for us to memorize a large number of words.Then reading and writing ability is another difficulty.Without a good mastery of vocabulary and grammar,we can't understand what the sentences mean in the text and don't know how to write an article.However,only if we have a regular study in English learning,can we deal with them.

An Assessment of English Instruction for Elementary-Level Students in Jeddah Governorate, as Perceived by English Supervisors and Educators

This study investigated the perceptions of English educators and supervisors in Jeddah Governorate regarding the process of teaching English to elementary students.A survey was conducted using a sample size of 94 educators and 10 supervisors.The data indicate that respondents considered English instruction at the elementary level essential for expanding kids’perspectives,improving academic performance,and promoting international involvement.The main advantages cited are the development of English language skills and the promotion of early education.Although not as easily noticeable,the disadvantages include potential negative impacts on an individual’s proficiency in Arabic and their sense of national identification.The highlighted challenges encompass insufficient teacher training,student reluctance towards English,limited resources,and school disparities.The proposed techniques focused on prioritizing English instructors’training,ensuring the use of appropriate content,utilizing technology,and promoting awareness of students and educators.The current research found different obstacles in teaching English at elementary stages.To overcome these obstacles,it will be essential to enhance teacher competencies,develop efficient teaching methods,get the backing of stakeholders,assign adequate resources,and carry out continuous evaluations.Further research can also contribute to a better understanding of how early English learning impacts on Arabic identity and proficiency.

Evidence for the Reliability and Validity of the Arabic Version of the Student Risk Screening Scale for Internalizing and Externalizing Behaviors (SRSS-IE)

School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric properties are critical to making decisions about choosing a screening instrument. The purpose of the present study was to examine the psychometric properties of the student risk screening scale for internalizing and externalizing behaviors (SRSS-IE). Participants included 3145 students and their teachers. Item-level analyses of the current sample supported the retention of all items. The internal consistency of the SRSS items ranged from 0.83 to 0.85. Convergent validity between the SRSS-IE and a well-established screening tool, the strength and difficulties questionnaire (SDQ), was found for the total score (r = 0.70). Additionally, the results of this study demonstrate strong social validity, suggesting the SRSS-IE to be a useful and functional screening tool. We conclude that the SRSS-IE is a valid and reliable instrument for assessing the level of emotional and behavioral difficulties among elementary students.