BACKGROUND For intrahepatic duct(IHD)stones,laparoscopic liver resection(LLR)is currently a reliable treatment.However,the current LLR difficulty scoring system(DSS)is only available for patients with hepatocellular c...BACKGROUND For intrahepatic duct(IHD)stones,laparoscopic liver resection(LLR)is currently a reliable treatment.However,the current LLR difficulty scoring system(DSS)is only available for patients with hepatocellular carcinoma.AIM To explore the development of a DSS for IHD stone patients with LLR and the validation of its reliability.METHODS We used clinical data from 80 patients who received LLR for IHD stones.Forty-six of these patients were used in multiple linear regression to construct a scoring system.Another 34 patients from different centers were used as external validation.The completeness of our DSS was then evaluated in patients with varying degrees of surgical difficulty based on documented surgical outcomes in the study group of patients.RESULTS The following five predictors were ultimately included and scored by calculating the weighted contribution of each factor to the prediction of operative time in the training cohort:Location of stones,number of stones≥3,stones located in the bile ducts of several grades,previous biliary surgery less than twice,distal bile duct atrophy.Subsequently,the data set was validated using a DSS developed from the variables.The following variables were identified as statistically significant in external validation:Operative time,blood loss,intraoperative transfusion,postoperative alanine aminotransferase,and Clavien-Dindo grading≥3.These variables demonstrated statistically significant differences in patients with three or more grades.CONCLUSION Patients with IHD stones have varying degrees of surgical difficulty,and the newly developed DSS can be validated with external data to effectively predict risks and complications after LLR surgery.展开更多
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 ...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.展开更多
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...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.展开更多
This experimental study investigated how text difficulty and different working memory capacity(WMC)affected Chinese EFL learners’reading comprehension and their tendency to engage in task-unrelated thoughts,that is,m...This experimental study investigated how text difficulty and different working memory capacity(WMC)affected Chinese EFL learners’reading comprehension and their tendency to engage in task-unrelated thoughts,that is,mind wandering(MW),in the course of reading.Sixty first-year university non-English majors participated in the study.A two-factor mixed experimental design of 2(text difficulty:difficult and simple)×2(WMC:high/large and low/small)was employed.Results revealed that 1)the main and interaction effects of WMC and text difficulty on voluntary MW were significant,whereas those on involuntary MW were not;2)while reading the easy texts,the involuntary MW of high-WMC individuals was less frequent than that of low-WMC ones,whereas while reading the difficult ones,the direct relationship between WMC and involuntary MW was not found;and that 3)high-WMC individuals had a lower overall rate of MW and better reading performance than low-WMC individuals did,but with increasing text difficulty,their rates of overall MW and voluntary MW were getting higher and higher,and the reading performance was getting lower and lower.These results lend support to WM theory and have pedagogical implications for the instruction of L2 reading.展开更多
Objective: To study the application effect of mouth-opening training sticks combined with oral massage on patients with mouth-opening difficulty after treatment for head and neck cancer. Methods: Using convenient samp...Objective: To study the application effect of mouth-opening training sticks combined with oral massage on patients with mouth-opening difficulty after treatment for head and neck cancer. Methods: Using convenient sampling, 60 patients with mouth-opening difficulty after treatment for head and neck cancer admitted to the Oncology Department from February 2022 to October 2023 were selected for a 2-week exercise and nursing program. The patients were divided into a control group (February 1, 2022 to November 30, 2022) and an observation group (December 1, 2022 to October 31, 2023), with 30 patients in each group. The control group underwent routine mouth-opening functional exercises combined with cork for oral support training, while the observation group underwent routine mouth-opening functional exercises combined with oral massage and mouth-opening training sticks for oral support training. The mouth-opening degree, mouth-opening difficulty level, comfort level, compliance, and quality of life were observed in both groups. Results: Before the intervention, there were no statistically significant differences in mouth-opening degree and mouth-opening difficulty level between the two groups (P > 0.05). After the intervention, the mouth-opening degree, mouth-opening difficulty level, oral comfort level, compliance, and QLICP-HN scores in the observation group were all better than those in the control group, with statistically significant differences (P < 0.05). Conclusion: The combination of mouth-opening training sticks and oral massage with mouth-opening functional exercises can effectively improve the degree of mouth-opening difficulty, enhance oral comfort, increase compliance with mouth-opening exercises, and improve quality of life.展开更多
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...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.展开更多
The difficulty of extracting hidden information, which is essentially a kindof secrecy, is analyzed by information-theoretic method. The relations between key rate, messagerate, hiding capacity and difficulty of extra...The difficulty of extracting hidden information, which is essentially a kindof secrecy, is analyzed by information-theoretic method. The relations between key rate, messagerate, hiding capacity and difficulty of extraction are studied in the terms of unicity distance ofstego-key, and the theoretic conclusion is used to analyze the actual extracting attack on LeastSignificant Bit(LSB) steganographic algorithms.展开更多
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 evaluatio...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.展开更多
Distinguishing the difficulty degree of top coal caving was a precondition of the popularization and application of the roadway sub-level caving in steep seam. Because of complexity and uncertainty of the coal seam, t...Distinguishing the difficulty degree of top coal caving was a precondition of the popularization and application of the roadway sub-level caving in steep seam. Because of complexity and uncertainty of the coal seam, the expression of influence factors was diffi-culty with exact data. According to the fuzzy and uncertainty of influence factors, triangular fuzzy membership functions were adopted to carry out the factors ambiguity, of which the factors not only have the consistency of semantic meaning, but also dissolve sufficiently expert knowledge. Based on the properties and structures of fasART fuzzy neural net-works of fuzzy logic system and practical needs, a simplified fasART model was put for-ward, stability and reliability of the network were improved, the deficiency of learning sam-ples and uncertainty of the factors were better treated. The method is of effective and practical value was identified by experiments.展开更多
This paper expounds the necessity of constructing China's rural multiplex financial system as follows.First,overcome the bottleneck effect arising from the shortage of capital in the process of development of rura...This paper expounds the necessity of constructing China's rural multiplex financial system as follows.First,overcome the bottleneck effect arising from the shortage of capital in the process of development of rural small and medium-sized enterprise,and increase farmers' income;second,provide capital support for rural modern industrial development,and promote rural economic development;third,rationally allocate capital,master the money flow and coordinate urban-rural development.The paper also profoundly analyzes the difficulties of constructing China's rural multiplex financial system as follows.First,the existing rural financial system structure is irrational and the function is unsound;second,non-governmental financial market is disorderly and the organization is unsound;third,the rural financial system is simple and the overhaul of rural credit cooperatives system has not yet been done;fourth,the construction of rural system of financial laws and regulations is laggard,and the construction of rural multiplex financial system lacks good social environment.The specific thoughts,measures and countermeasures of constructing mechanism innovation of China's rural multiplex financial system are put forward as follows.First,increasingly perfect legal system and provide legal support for constructing China's rural multiplex financial system;second,quicken the overhaul of rural credit cooperatives system and perfect its function in China's rural multiplex financial system;third,strengthen the degree of support and development,and change the situation of simple structure of rural financial system;fourth,reinforce administrative supervision and perfect public services,and standardize the rural financial market order.展开更多
Probabilistic method requires a lot of sample information to describe the probability distributions of uncertain variables and has difficulty in dealing with the optimization problem with uncertain parameters which co...Probabilistic method requires a lot of sample information to describe the probability distributions of uncertain variables and has difficulty in dealing with the optimization problem with uncertain parameters which contains unsufficient information.To solve this problem,a robust optimization operation method based on information gap decision theory(IGDT) is presented considering the non-probabilistic uncertainties of parameters.By the proposed method the maximum resistance to the disturbance of uncertain parameters is achieved and the optimization strategies with uncertain parameters are presented.Finally,numerical simulation is performed on the modified IEEE-14 bus system.Numerical results show the effectiveness of the proposed approach.展开更多
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 le...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.展开更多
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 ...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.展开更多
Transcranial direct current stimulation (tDCS), an emerging technique for non-invasive brain stimulation, is increasingly used to induce changes in cortical excitability and modulate motor behavior, especially for u...Transcranial direct current stimulation (tDCS), an emerging technique for non-invasive brain stimulation, is increasingly used to induce changes in cortical excitability and modulate motor behavior, especially for upper limbs. The purpose of this study was to investigate the effects of tDCS of the primary motor cortex on visuomotor coordination based on three levels of task difficulty in healthy subjects. Thirty-eight healthy participants underwent real tDCS or sham tDCS. Using a single-blind, sham-controlled crossover design, tDCS was applied to the primary motor cortex. For real tDCS conditions, tDCS intensity was 1 mA while stimulation was applied for 15 minutes. For the sham tDCS, electrodes were placed in the same position, but the stimu- lator was turned off after 5 seconds. Visuomotor tracking task, consisting of three levels (levels 1, 2, 3) of difficulty with higher level indicating greater difficulty, was performed before and after tDCS application. At level 2, real tDCS of the primary motor cortex improved the accurate index compared to the sham tDCS. However, at levels 1 and 3, the accurate index was not significantly increased after real tDCS compared to the sham tDCS. These findings suggest that tasks of mod- erate difficulty may improve visuomotor coordination in healthy subjects when tDCS is applied compared with easier or more difficult tasks.展开更多
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 performe...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.展开更多
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 m...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.展开更多
In order to have the optimal capital structure, the company with higher volatility of return adjusts the capital structure more frequently and has shorter debt maturity. Investors also have shorter investment cycle on...In order to have the optimal capital structure, the company with higher volatility of return adjusts the capital structure more frequently and has shorter debt maturity. Investors also have shorter investment cycle on these companies. Investment cycle is also affected by information asymmetry. The less asymmetric the information is, the more information investors get and the longer the investment cycle is. The adjustment frequency is also restricted by financial strength. This paper measures the debt maturity structure of the firm as the weighted average of debt maturity, and it is more precise than the ratio of long term debt to total debt. In empirical tests on debt maturity, the results show that financial strength, volatility of return and asymmetric information all have negative impacts on debt maturity.展开更多
Background: Unsafe abortions are one of the leading causes of maternal mortality, especially in developing countries. In Cameroon, the maternal mortality rate remains high, and the scarcity of data on abortions leads ...Background: Unsafe abortions are one of the leading causes of maternal mortality, especially in developing countries. In Cameroon, the maternal mortality rate remains high, and the scarcity of data on abortions leads to a lack of solid evidence to advocate on the extent of the abortions related complications. Our objective was to evaluate the unsafe abortions related complications, and to assess the difficulties of accessing safe abortions in our setting. Methods: We carried out a meta-analytic and systematic review in the biomedical databases MEDLINE (Pubmed), Google Scholar and African Journal Online concerning unsafe abortions and/or difficulties in accessing safe abortions in Cameroon. The keywords used for the search are seen in table I. Selection of studies was simultaneously done by two authors. Data were extracted through a form designed on Google Form. We used a random-effect model for proportion estimation, and The I<sup>2</sup> and Q statistics to assess the extent of heterogeneity. Results: A total of 430 studies were identified, from which 28 were included and analysed. About 5% (95% CI: 3 - 7) of unsafe abortions leads to death. The contribution of unsafe abortions in maternal deaths was 23% (95% CI: 20 - 27). The rate of severe bleeding and/or anemia were 40% (95% CI: 18 - 63) and the rate of infection was 17% (95% CI: 7 - 28), dominated by pelvic infections, pelviperitonitis, severe sepsis, and septic shock. Case reports described uterine perforations, uterine rupture during the following pregnancy. Abortion was performed in the practitioner’s or patient’s home in 41.4% of cases, in a health center in 35.1% of cases, in a private clinic in 21.2% of cases, drugs selling places and in traditional healer clinics. The restriction of abortion laws, the stigma surrounding abortion and its consequences at any level of the society, lead to the underreporting of unsafe abortions and a deep reluctance to advocate for safe abortion services. Conclusion: The strengthening of awareness campaigns for provider behavior change communication, family planning, the de-stigmatization of abortions, the training of health personnel in post-abortion care, a multidisciplinary and multicentric action would contribute to the reduction in morbidity and mortality due to abortions.展开更多
Unsafe abortions constitute a public health problem. It is one of the causes of maternal mortality in the world and particularly in developing countries. Despite the progress made, maternal mortality remains high in C...Unsafe abortions constitute a public health problem. It is one of the causes of maternal mortality in the world and particularly in developing countries. Despite the progress made, maternal mortality remains high in Cameroon. The scarcity and disparity of data on abortions lead to a lack of strong evidence to advocate to decision-makers on the extent of the problems associated with abortions in Cameroon. Our objective is to estimate the rates of mortalities and complications related to unsafe abortions, as well as the difficulties of accessing safe abortions in Cameroon. We will carry out a systematic and meta-analytical review in the biomedical databases MEDLINE (Pubmed), Google Scholar and African Journal Online (AJOL) concerning unsafe abortions and/or difficulties in accessing safe abortions in Cameroon, without date or language restriction. Gray literature will be also consulted. Two authors will simultaneously select the studies and data extraction will be done using a Google Form. Proportions will be estimated on a random-effect model. The I<sup>2</sup> and Q statistics will be used to assess the extent of heterogeneity across the studies. The outcome of both the quantitative and qualitative parts of the study will be commented. Death and morbidity due to abortions can be prevented. A concerted multidisciplinary and multicentric action would be essential.展开更多
This study examined the relationship between budget participation and managerial performance as mediated by trust in supervisor and explored the moderating role of budget-goal difficulty on budget participation, trust...This study examined the relationship between budget participation and managerial performance as mediated by trust in supervisor and explored the moderating role of budget-goal difficulty on budget participation, trust in supervisor, and managerial performance. One-hundred-fifty-eight useful responses were drawn at random from subordinate managers of manufacturing companies listed on the Taiwan Stock Exchange. The mediating effect of trust in supervisor was examined by path analysis. Subgroup analysis was used to examine the contingency effect of budget-goal difficulty on the mediating role of trust in supervisor between budget participation and performance. The findings support our hypotheses and demonstrate the mediating effect of trust in supervisor and the moderating effect of budget-goal difficulty.展开更多
文摘BACKGROUND For intrahepatic duct(IHD)stones,laparoscopic liver resection(LLR)is currently a reliable treatment.However,the current LLR difficulty scoring system(DSS)is only available for patients with hepatocellular carcinoma.AIM To explore the development of a DSS for IHD stone patients with LLR and the validation of its reliability.METHODS We used clinical data from 80 patients who received LLR for IHD stones.Forty-six of these patients were used in multiple linear regression to construct a scoring system.Another 34 patients from different centers were used as external validation.The completeness of our DSS was then evaluated in patients with varying degrees of surgical difficulty based on documented surgical outcomes in the study group of patients.RESULTS The following five predictors were ultimately included and scored by calculating the weighted contribution of each factor to the prediction of operative time in the training cohort:Location of stones,number of stones≥3,stones located in the bile ducts of several grades,previous biliary surgery less than twice,distal bile duct atrophy.Subsequently,the data set was validated using a DSS developed from the variables.The following variables were identified as statistically significant in external validation:Operative time,blood loss,intraoperative transfusion,postoperative alanine aminotransferase,and Clavien-Dindo grading≥3.These variables demonstrated statistically significant differences in patients with three or more grades.CONCLUSION Patients with IHD stones have varying degrees of surgical difficulty,and the newly developed DSS can be validated with external data to effectively predict risks and complications after LLR surgery.
文摘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.
基金Institutional review board statement:The study was reviewed and approved by the Wenzhou Central Hospital Institutional Review Board(Approval No.K2018-01-003).
文摘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.
文摘This experimental study investigated how text difficulty and different working memory capacity(WMC)affected Chinese EFL learners’reading comprehension and their tendency to engage in task-unrelated thoughts,that is,mind wandering(MW),in the course of reading.Sixty first-year university non-English majors participated in the study.A two-factor mixed experimental design of 2(text difficulty:difficult and simple)×2(WMC:high/large and low/small)was employed.Results revealed that 1)the main and interaction effects of WMC and text difficulty on voluntary MW were significant,whereas those on involuntary MW were not;2)while reading the easy texts,the involuntary MW of high-WMC individuals was less frequent than that of low-WMC ones,whereas while reading the difficult ones,the direct relationship between WMC and involuntary MW was not found;and that 3)high-WMC individuals had a lower overall rate of MW and better reading performance than low-WMC individuals did,but with increasing text difficulty,their rates of overall MW and voluntary MW were getting higher and higher,and the reading performance was getting lower and lower.These results lend support to WM theory and have pedagogical implications for the instruction of L2 reading.
文摘Objective: To study the application effect of mouth-opening training sticks combined with oral massage on patients with mouth-opening difficulty after treatment for head and neck cancer. Methods: Using convenient sampling, 60 patients with mouth-opening difficulty after treatment for head and neck cancer admitted to the Oncology Department from February 2022 to October 2023 were selected for a 2-week exercise and nursing program. The patients were divided into a control group (February 1, 2022 to November 30, 2022) and an observation group (December 1, 2022 to October 31, 2023), with 30 patients in each group. The control group underwent routine mouth-opening functional exercises combined with cork for oral support training, while the observation group underwent routine mouth-opening functional exercises combined with oral massage and mouth-opening training sticks for oral support training. The mouth-opening degree, mouth-opening difficulty level, comfort level, compliance, and quality of life were observed in both groups. Results: Before the intervention, there were no statistically significant differences in mouth-opening degree and mouth-opening difficulty level between the two groups (P > 0.05). After the intervention, the mouth-opening degree, mouth-opening difficulty level, oral comfort level, compliance, and QLICP-HN scores in the observation group were all better than those in the control group, with statistically significant differences (P < 0.05). Conclusion: The combination of mouth-opening training sticks and oral massage with mouth-opening functional exercises can effectively improve the degree of mouth-opening difficulty, enhance oral comfort, increase compliance with mouth-opening exercises, and improve quality of life.
文摘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.
文摘The difficulty of extracting hidden information, which is essentially a kindof secrecy, is analyzed by information-theoretic method. The relations between key rate, messagerate, hiding capacity and difficulty of extraction are studied in the terms of unicity distance ofstego-key, and the theoretic conclusion is used to analyze the actual extracting attack on LeastSignificant Bit(LSB) steganographic algorithms.
基金the financial support from the Natural Science Foundation of China(Grant Nos.51904317 and 51821092)Science Foundation of China University of Petroleum,Beijing(Grant No.ZX20180414)other projects(ZLZX2020-0107-01)
文摘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.
文摘Distinguishing the difficulty degree of top coal caving was a precondition of the popularization and application of the roadway sub-level caving in steep seam. Because of complexity and uncertainty of the coal seam, the expression of influence factors was diffi-culty with exact data. According to the fuzzy and uncertainty of influence factors, triangular fuzzy membership functions were adopted to carry out the factors ambiguity, of which the factors not only have the consistency of semantic meaning, but also dissolve sufficiently expert knowledge. Based on the properties and structures of fasART fuzzy neural net-works of fuzzy logic system and practical needs, a simplified fasART model was put for-ward, stability and reliability of the network were improved, the deficiency of learning sam-ples and uncertainty of the factors were better treated. The method is of effective and practical value was identified by experiments.
文摘This paper expounds the necessity of constructing China's rural multiplex financial system as follows.First,overcome the bottleneck effect arising from the shortage of capital in the process of development of rural small and medium-sized enterprise,and increase farmers' income;second,provide capital support for rural modern industrial development,and promote rural economic development;third,rationally allocate capital,master the money flow and coordinate urban-rural development.The paper also profoundly analyzes the difficulties of constructing China's rural multiplex financial system as follows.First,the existing rural financial system structure is irrational and the function is unsound;second,non-governmental financial market is disorderly and the organization is unsound;third,the rural financial system is simple and the overhaul of rural credit cooperatives system has not yet been done;fourth,the construction of rural system of financial laws and regulations is laggard,and the construction of rural multiplex financial system lacks good social environment.The specific thoughts,measures and countermeasures of constructing mechanism innovation of China's rural multiplex financial system are put forward as follows.First,increasingly perfect legal system and provide legal support for constructing China's rural multiplex financial system;second,quicken the overhaul of rural credit cooperatives system and perfect its function in China's rural multiplex financial system;third,strengthen the degree of support and development,and change the situation of simple structure of rural financial system;fourth,reinforce administrative supervision and perfect public services,and standardize the rural financial market order.
基金National Natural Science Foundation of China(No.61533010)Science and Technology Commission of Shanghai Municipality,China(No.14ZR1415300)
文摘Probabilistic method requires a lot of sample information to describe the probability distributions of uncertain variables and has difficulty in dealing with the optimization problem with uncertain parameters which contains unsufficient information.To solve this problem,a robust optimization operation method based on information gap decision theory(IGDT) is presented considering the non-probabilistic uncertainties of parameters.By the proposed method the maximum resistance to the disturbance of uncertain parameters is achieved and the optimization strategies with uncertain parameters are presented.Finally,numerical simulation is performed on the modified IEEE-14 bus system.Numerical results show the effectiveness of the proposed approach.
文摘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.
文摘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.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT&Future Planning,No.2012R1A1B4003477
文摘Transcranial direct current stimulation (tDCS), an emerging technique for non-invasive brain stimulation, is increasingly used to induce changes in cortical excitability and modulate motor behavior, especially for upper limbs. The purpose of this study was to investigate the effects of tDCS of the primary motor cortex on visuomotor coordination based on three levels of task difficulty in healthy subjects. Thirty-eight healthy participants underwent real tDCS or sham tDCS. Using a single-blind, sham-controlled crossover design, tDCS was applied to the primary motor cortex. For real tDCS conditions, tDCS intensity was 1 mA while stimulation was applied for 15 minutes. For the sham tDCS, electrodes were placed in the same position, but the stimu- lator was turned off after 5 seconds. Visuomotor tracking task, consisting of three levels (levels 1, 2, 3) of difficulty with higher level indicating greater difficulty, was performed before and after tDCS application. At level 2, real tDCS of the primary motor cortex improved the accurate index compared to the sham tDCS. However, at levels 1 and 3, the accurate index was not significantly increased after real tDCS compared to the sham tDCS. These findings suggest that tasks of mod- erate difficulty may improve visuomotor coordination in healthy subjects when tDCS is applied compared with easier or more difficult tasks.
文摘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.
文摘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.
文摘In order to have the optimal capital structure, the company with higher volatility of return adjusts the capital structure more frequently and has shorter debt maturity. Investors also have shorter investment cycle on these companies. Investment cycle is also affected by information asymmetry. The less asymmetric the information is, the more information investors get and the longer the investment cycle is. The adjustment frequency is also restricted by financial strength. This paper measures the debt maturity structure of the firm as the weighted average of debt maturity, and it is more precise than the ratio of long term debt to total debt. In empirical tests on debt maturity, the results show that financial strength, volatility of return and asymmetric information all have negative impacts on debt maturity.
文摘Background: Unsafe abortions are one of the leading causes of maternal mortality, especially in developing countries. In Cameroon, the maternal mortality rate remains high, and the scarcity of data on abortions leads to a lack of solid evidence to advocate on the extent of the abortions related complications. Our objective was to evaluate the unsafe abortions related complications, and to assess the difficulties of accessing safe abortions in our setting. Methods: We carried out a meta-analytic and systematic review in the biomedical databases MEDLINE (Pubmed), Google Scholar and African Journal Online concerning unsafe abortions and/or difficulties in accessing safe abortions in Cameroon. The keywords used for the search are seen in table I. Selection of studies was simultaneously done by two authors. Data were extracted through a form designed on Google Form. We used a random-effect model for proportion estimation, and The I<sup>2</sup> and Q statistics to assess the extent of heterogeneity. Results: A total of 430 studies were identified, from which 28 were included and analysed. About 5% (95% CI: 3 - 7) of unsafe abortions leads to death. The contribution of unsafe abortions in maternal deaths was 23% (95% CI: 20 - 27). The rate of severe bleeding and/or anemia were 40% (95% CI: 18 - 63) and the rate of infection was 17% (95% CI: 7 - 28), dominated by pelvic infections, pelviperitonitis, severe sepsis, and septic shock. Case reports described uterine perforations, uterine rupture during the following pregnancy. Abortion was performed in the practitioner’s or patient’s home in 41.4% of cases, in a health center in 35.1% of cases, in a private clinic in 21.2% of cases, drugs selling places and in traditional healer clinics. The restriction of abortion laws, the stigma surrounding abortion and its consequences at any level of the society, lead to the underreporting of unsafe abortions and a deep reluctance to advocate for safe abortion services. Conclusion: The strengthening of awareness campaigns for provider behavior change communication, family planning, the de-stigmatization of abortions, the training of health personnel in post-abortion care, a multidisciplinary and multicentric action would contribute to the reduction in morbidity and mortality due to abortions.
文摘Unsafe abortions constitute a public health problem. It is one of the causes of maternal mortality in the world and particularly in developing countries. Despite the progress made, maternal mortality remains high in Cameroon. The scarcity and disparity of data on abortions lead to a lack of strong evidence to advocate to decision-makers on the extent of the problems associated with abortions in Cameroon. Our objective is to estimate the rates of mortalities and complications related to unsafe abortions, as well as the difficulties of accessing safe abortions in Cameroon. We will carry out a systematic and meta-analytical review in the biomedical databases MEDLINE (Pubmed), Google Scholar and African Journal Online (AJOL) concerning unsafe abortions and/or difficulties in accessing safe abortions in Cameroon, without date or language restriction. Gray literature will be also consulted. Two authors will simultaneously select the studies and data extraction will be done using a Google Form. Proportions will be estimated on a random-effect model. The I<sup>2</sup> and Q statistics will be used to assess the extent of heterogeneity across the studies. The outcome of both the quantitative and qualitative parts of the study will be commented. Death and morbidity due to abortions can be prevented. A concerted multidisciplinary and multicentric action would be essential.
文摘This study examined the relationship between budget participation and managerial performance as mediated by trust in supervisor and explored the moderating role of budget-goal difficulty on budget participation, trust in supervisor, and managerial performance. One-hundred-fifty-eight useful responses were drawn at random from subordinate managers of manufacturing companies listed on the Taiwan Stock Exchange. The mediating effect of trust in supervisor was examined by path analysis. Subgroup analysis was used to examine the contingency effect of budget-goal difficulty on the mediating role of trust in supervisor between budget participation and performance. The findings support our hypotheses and demonstrate the mediating effect of trust in supervisor and the moderating effect of budget-goal difficulty.