[ Objective] The research aimed to contrast and analyze meteorological factors between Zhongshan station of the South Pole and Chi- nese inland. [ Method ] Based on meteorological observation data at Zhongshan station...[ Objective] The research aimed to contrast and analyze meteorological factors between Zhongshan station of the South Pole and Chi- nese inland. [ Method ] Based on meteorological observation data at Zhongshan station of the South Pole since established, contrast and analysis were taken on the atmospheric temperature, relative humidity and atmospheric pressure with that at Shanghe station of Chinese inland, to find out variation laws of the each meteorological factor in the two stations, and to analyze different change relations among factors. [ Result] Although geo- graphic positions of the two stations were different, and they were respectively in south and north hemispheres, each meteorological factor at the two stations had same change rules. Interannual anomaly relationship of the meteorological factor had certain rule. That was to say, variation of the positive or negative anomaly advanced or lagged for 1 -2 years. [ Conclusion] The research had reference value for studying global climatic variation.展开更多
There are many idioms related to color words in English and Chinese.The use of color words in idioms adds beauty and vividness to the language.Due to the cultural differences,“color idioms”have gained different cult...There are many idioms related to color words in English and Chinese.The use of color words in idioms adds beauty and vividness to the language.Due to the cultural differences,“color idioms”have gained different cultural connotations with the development of English and Chinese languages.It is of great significance to accurately understand and grasp the meanings and differences of color-related idioms in Chinese and English.This paper intends to analyze and expound the cultural connotations of English and Chinese idioms related to several widely used basic color words with the aim of helping English learners know and use the idioms about color words better.展开更多
Based on the theory of thematic complexity, a contrastive analysis on 2 sections selected from research articles-method and discussion, was conducted. The differences and similarities between the 2 sections in simple ...Based on the theory of thematic complexity, a contrastive analysis on 2 sections selected from research articles-method and discussion, was conducted. The differences and similarities between the 2 sections in simple theme, multiple theme, textual theme, interpersonal theme, topical theme and thematic progression were analyzed and concluded. The author believes that the causes of the differences and similarities are the different genre features of the 2 sections and the academic features of the materials selected.展开更多
For the safety protection of passengers when train crashes occur, special structures are crucially needed as a kind of indispensable energy absorbing device. With the help of the structures, crash kinetic-energy can b...For the safety protection of passengers when train crashes occur, special structures are crucially needed as a kind of indispensable energy absorbing device. With the help of the structures, crash kinetic-energy can be completely absorbed or dissipated for the aim of safety. Two composite structures(circumscribed circle structure and inscribed circle structure) were constructed. In addition, comparison and optimization of the crashworthy characteristic of the two structures were carried out based on the method of explicit finite element analysis(FEA) and Kriging surrogate model. According to the result of Kriging surrogate model, conclusions can be safely drawn that the specific energy absorption(SEA) and ratio of specific energy absorption to initial peak force(REAF) of circumscribed circle structure are lager than those of inscribed circle structure under the same design parameters. In other words, circumscribed circle structure has better performances with higher energy-absorbing ability and lower initial peak force. Besides, error analysis was adopted and the result of which indicates that the Kriging surrogate model has high nonlinear fitting precision. What is more, the SEA and REAF optimum values of the two structures have been obtained through analysis, and the crushing results have been illustrated when the two structures reach optimum SEA and REAF.展开更多
Once more to the lake is a representative work of the American Writer, Elwyn Brooks White, and has been acclaimed by people in the world. The paper offers a three-layered contrasting analysis of the essay. By detailed...Once more to the lake is a representative work of the American Writer, Elwyn Brooks White, and has been acclaimed by people in the world. The paper offers a three-layered contrasting analysis of the essay. By detailed analysis of the contrasts running through the whole essay, the author finds that those contrasts are symbol of White's internal struggle and reflection for life.On the foundation of the three-layered contrasts, the paper presents the theme analysis and clarifies the content of the essay.展开更多
[Objective] The research aimed to contrast parallel observation data of pressure and temperature in Qingxian station. [Method] By u- sing pressure and temperature observed by automatic station and artificial station i...[Objective] The research aimed to contrast parallel observation data of pressure and temperature in Qingxian station. [Method] By u- sing pressure and temperature observed by automatic station and artificial station in Qingxian from January of 2009 to December of 2010, compara- tive analysis of observation data was conducted, and formation reason of difference value was discussed. E Resultl Monthly average pressure differ- ence between automatic station and artificial observation value was from -0.7 to 0.1 hPa. Difference value of monthly average maximum pressure was from -0.5 to 0.4 hPa, while difference value of monthly average minimum pressure was from -0.7 to 0.2 hPa. Difference value of monthly extremely maximum pressure was from -0.3 to 0.6 hPa, while difference value of monthly extremely minimum pressure was from -1.1 to 0.1 hPa. Monthly average temperature difference value was from -2.0 to 0 ℃. Difference value of monthly average maximum temperature was from -0.4 to 0 ℃, while difference value of monthly average minimum temperature was from -0.1 to 0.2 ℃. Difference value of monthly extremely maximum temperature was from -0.3 to 0.3 ℃, while difference value of monthly extremely minimum temperature was from -0.3 to 0.3 ℃. [ Conclusion] Generation reason of observation difference mainly included differences of observation instrument and principle, differences of data collection time and method, different sensor installation positions and environments, manual intervention and observation error.展开更多
I Introduction The fact that we are human beings who live together in society determines that much that we want to accomplish can be done only through social communication with other people. It is under
Learning to handle hypothetical situations in a new language is always difficult(Catford,et al.,1974).This rule holds true for Moroccan Arabic(henceforth MA)speakers learning English because grammatical devices in the...Learning to handle hypothetical situations in a new language is always difficult(Catford,et al.,1974).This rule holds true for Moroccan Arabic(henceforth MA)speakers learning English because grammatical devices in the two languages differ in almost all equivalent situations.For instance,while English verb forms are used to indicate tense in conditional sentences,MA uses them to indicate aspect.Adopting the typology of conditional constructions suggested by Dancygier(1999)and Dancygier&Sweetser(2005),this study provides a contrastive analysis of conditionals in English and MA to predict the possible errors EFL/ESL learners are likely to make while learning English.The analysis shows that the main discrepancy between English conditionals and MA conditionals lies in the verb form used by the two systems.Accordingly,if EFL/ESL learners are influenced by verb form in their L1,they are likely to face some challenges while learning English conditionals.That is,they are likely to use the past tense in the protases of English predictive conditionals and generic conditionals since the perfective form of the verb is used in the protases of these two types in MA.Concerning the protases of English non-predictive conditionals,Moroccan EFL/ESL learners are likely to use either the past tense or the present tense since both the perfective and the imperfective forms of the verb are possible in the protases of MA non-predictive conditionals.However,due to the fact that the perfective form is the prototypical form in the protases of conditionals in MA,EFL/ESL learners are likely to use the past tense more often than the present tense.The analysis also shows that EFL/ESL learners tend to use the present tense in the apodoses of English conditionals since the prevalent form in the apodoses of MA conditionals is the imperfective.展开更多
Based on ideational,interpersonal,and textual metafunctions in systemic functional linguistics(SFL),a contrastive analysis is carried out on two same-topic news reports of Chinese and American main stream media.Two re...Based on ideational,interpersonal,and textual metafunctions in systemic functional linguistics(SFL),a contrastive analysis is carried out on two same-topic news reports of Chinese and American main stream media.Two reports from the People’s Daily and CNN are analyzed in terms of the lexical-grammatical systems(transitivity,mood and modality,and theme)realizing the three corresponding metafunctions to compare Chinese and American media reports on the same event.Results show that the two reports deploy different transitivity processes,but indicate similarity in the uses of mood and thematic choices.There are also respective preferences for reporting the sametopic news:CNN focuses on the whole process of the incident,the report being relatively objective and fair without obvious emotional bias,while the report of People’s Daily is relatively comprehensive,analyzing the incident from various angles,and playing a positive role in guiding public opinion.展开更多
With the rapid development of the UHV power grid, evaluation of the economic and social benefits of the UHV power grid is conducive to guiding the planning and construction of UHV power grid. At present economic benef...With the rapid development of the UHV power grid, evaluation of the economic and social benefits of the UHV power grid is conducive to guiding the planning and construction of UHV power grid. At present economic benefit evaluation system of the UHV power grid is driving to maturity stage on the whole at home and abroad, but it invariably tends to regard social benefits as part of economic benefits, without evaluating social benefit separately. The social benefit evaluation model of UHV power grid is built in case of sufficient investigation. The differentials between social benefit and social cost are calculated respectively by three kinds of solutions according to the constructed social cost evaluation index system and social benefits evaluation index system, conclusion that UHV power grid transmission has better social benefits can be reached by contrastively analyzing the social three kinds of solutions corresponding to benefits. At last, the evaluation model and method are verified and analyzed through the analysis of engineering projects.展开更多
Back-translation is the translation of a translated text back into the language of the original text, which is an effective way to ensure accurate translation and assumes to be beneficial to improving learner＇s Engli...Back-translation is the translation of a translated text back into the language of the original text, which is an effective way to ensure accurate translation and assumes to be beneficial to improving learner＇s English competence. This thesis, based on the author＇s back translation training exercise, intends to make a constrastive study of source text in English and its back-translation precisely from the aspects of word choice, collocation, and sentence mechanics. Results have shown that by doing back-translation practice, the learners will strengthen their awareness of language differences between English and Chinese. Besides, as a special kind of translation, back-translation has its implications on English learning and Chinese-English translation, such as being a recitation method and testing tool.展开更多
According to sociolinguistic research of speech events, the choice of linguistic forms is determined by the formality of the context and the relationship between interlocutors in a speech event. In this respect, addre...According to sociolinguistic research of speech events, the choice of linguistic forms is determined by the formality of the context and the relationship between interlocutors in a speech event. In this respect, address forms are socially driven phenomena which make the fundamental point in sociolinguistics clearly. The attempt of this study will be made to discuss the impact of the cultures, especially people in America and China. Mainly, the paper is pertinent to ask some questions： （1） whether there are any different pronouns of address used in different cultures, （2） the discrepancy of forms of address used in America and China and how interlocutors used them respectively and （3） are there any semantic systems presented in both two cultures based upon interlocutors＇ social position and cultural background.展开更多
In this study, two comparative methods were selected to treat acute appendicitis, one is laparoscopic surgery, the other is open surgery, and two different surgical methods were used for clinical treatment. Methods: 7...In this study, two comparative methods were selected to treat acute appendicitis, one is laparoscopic surgery, the other is open surgery, and two different surgical methods were used for clinical treatment. Methods: 72 patients with acute appendicitis in our hospital were analyzed and studied from March 2019 to August 2021. The patients were divided into open group and laparoscopic group, with 31 patients in each group. In the open group and the laparoscopic group, the former chose open appendectomy and the latter chose laparoscopic appendectomy. Results: in the time of recovery of gastrointestinal function, time of getting out of bed after operation, amount of blood loss during operation, operation time and incision, the effect of patients in open abdominal group was significantly lower than that of patients in laparoscopic group (P < 0.05). The incidence of complications in the laparoscopic group was significantly higher than that in the open group, such as postoperative wound infection, postpoisoning marks, intestinal obstruction, abdominal abscess, etc. the difference was statistically significant (P < 0.05). Conclusion: in the clinical comparative analysis of the treatment of patients with acute appendicitis, laparoscopic appendectomy can effectively reduce the blood loss during the operation, improve the patients' postoperative recovery ability, reduce the hospitalization time and shorten the postoperative excretion time. The analysis and research show that, in the treatment of patients with acute appendicitis analyzed by the two groups, laparoscopic surgery is more suitable for the treatment of patients with acute appendicitis, can effectively reduce the occurrence of complications, and is more effective than open surgery. After the recovery, it can also well reduce the incidence of complications, and has higher clinical application value, so as to help patients recover as soon as possible.展开更多
Background:All neurons of the visual system exhibit response to differences in luminance.This neural response to visual contrast,also known as the contrast response function(CRF),follows a characteristic sigmoid shape...Background:All neurons of the visual system exhibit response to differences in luminance.This neural response to visual contrast,also known as the contrast response function(CRF),follows a characteristic sigmoid shape that can be fitted with the Naka-Rushton equation.Four parameters define the CRF,and they are often used in different visual research disciplines,since they describe selective variations of neural responses.As novel technologies have grown,the capacity to record thousands of neurons simultaneously brings new challenges:processing and robustly analyzing larger amounts of data to maximize the outcomes of our experimental measurements.Nevertheless,current guidelines to fit neural activity based on the Naka-Rushton equation have been poorly discussed in depth.In this study,we explore several methods of boundary-setting and least-square curve-fitting for the CRF in order to avoid the pitfalls of blind curve-fitting.Furthermore,we intend to provide recommendations for experimenters to better prepare a solid quantification of CRF parameters that also minimize the time of the data acquisition.For this purpose,we have created a simplified theoretical model of spike-response dynamics,in which the firing rate of neurons is generated by a Poisson process.The spike trains generated by the theoretical model depending on visual contrast intensities were then fitted with the Naka-Rushton equation.This allowed us to identify combinations of parameters that were more important to adjust before performing experiments,to optimize the precision and efficiency of curve fitting(e.g.,boundaries of CRF parameters,number of trials,number of contrast tested,metric of contrast used and the effect of including multi-unit spikes into a single CRF,among others).Several goodness-of-fit methods were also examined in order to achieve ideal fits.With this approach,it is possible to anticipate the minimal requirements to gather and analyze data in a more efficient way in order to build stronger functional models.Methods:Spike-trains were randomly generated following a Poisson distribution in order to draw both an underlying theoretical curve and an empirical one.Random noise was added to the fit to simulate empirical conditions.The correlation function was recreated on the simulated data and re-fit using the Naka-Rushton equation.The two curves were compared:the idea being to determine the most advantageous boundaries and conditions for the curve-fit to be optimal.Statistical analysis was performed on the data to determine those conditions for experiments.Experiments were then conducted to acquire data from mice and cats to verify the model.Results:Results were obtained successfully and a model was proposed to assess the goodness of the fit of the contrast response function.Various parametres and their influence of the model were tested.Other similar models were proposed and their performance was assessed and compared to the previous ones.The fit was optimized to give semi-strict guidelines for scientists to follow in order to maximize their efficiency while obtaining the contrast tuning of a neuron.Conclusions:The aim of the study was to assess the optimal testing parametres of the neuronal response to visual gratings with various luminance,also called the CRF.As technology gets more powerful and potent,one must make choices when experimenting.With a strong model,robust boundaries,and strong experimental conditioning,the best fit to a function can lead to more efficient analysis and stronger cognitive models.展开更多
The influence of temperatures on the stacking fault energies and deformation mechanism of a Re- containing single crystal nickel-based superalloy during creep at elevated temperatures was investigated by means of calc...The influence of temperatures on the stacking fault energies and deformation mechanism of a Re- containing single crystal nickel-based superalloy during creep at elevated temperatures was investigated by means of calculating the stacking fault energy of alloy, measuring creep properties and performing contrast analysis of dislocation configuration. The results show that the alloy at 760 ℃ possesses lower stacking fault energy, and the stacking fault of alloy increases with increasing temperature. The defor- mation mechanism of alloy during creep at 760 ℃ is 7＇ phase sheared by 〈110〉 super-dislocations, which may be decomposed to form the configuration of Shockley partials plus super-lattice intrinsic stacking fault, while the deformation mechanism of alloy during creep at 1070 ℃ is the screw or edge super- dislocations shearing into the rafted 7＇ phase. But during creep at 7（50 and 980 ℃, some super- dislocations shearing into 7＇ phase may cross-slip from the {111} to {100} planes to form the K-W locks with non-plane core structure, which may restrain the dislocations slipping to enhance the creep resis- tance of alloy at high temperature. The interaction between the Re and other elements may decrease the diffusion rate of atoms to improve the microstructure stability, which is thought to be the main reason why the K-W locks are to be kept in the Re-containing superalloy during creep at 980 ℃.展开更多
In this paper,a model-based reconstruction technique is proposed to simultaneously measure the relative deoxyhemoglobin concentration and the relative blood flow velocity in cerebral cortex.With the help of this model...In this paper,a model-based reconstruction technique is proposed to simultaneously measure the relative deoxyhemoglobin concentration and the relative blood flow velocity in cerebral cortex.With the help of this model-based reconstruction technique,artifacts due to nonuniform laser illumination and curvature of cortex are efficiently corrected.The results of relative deoxyhemoglobin concentration and relative blood flow velocity are then used to detect and distinguish cerebral arteries and veins.In an experimental study on rat,cerebral blood vessels are segmented from the reconstructed blood flow image by Otsu multiple threshold method.Afterwards,arteries and veins are distinguished by a simple fuzzy criterion based on the information of relative deoxyhemoglobin concentration.展开更多
文摘[ Objective] The research aimed to contrast and analyze meteorological factors between Zhongshan station of the South Pole and Chi- nese inland. [ Method ] Based on meteorological observation data at Zhongshan station of the South Pole since established, contrast and analysis were taken on the atmospheric temperature, relative humidity and atmospheric pressure with that at Shanghe station of Chinese inland, to find out variation laws of the each meteorological factor in the two stations, and to analyze different change relations among factors. [ Result] Although geo- graphic positions of the two stations were different, and they were respectively in south and north hemispheres, each meteorological factor at the two stations had same change rules. Interannual anomaly relationship of the meteorological factor had certain rule. That was to say, variation of the positive or negative anomaly advanced or lagged for 1 -2 years. [ Conclusion] The research had reference value for studying global climatic variation.
文摘There are many idioms related to color words in English and Chinese.The use of color words in idioms adds beauty and vividness to the language.Due to the cultural differences,“color idioms”have gained different cultural connotations with the development of English and Chinese languages.It is of great significance to accurately understand and grasp the meanings and differences of color-related idioms in Chinese and English.This paper intends to analyze and expound the cultural connotations of English and Chinese idioms related to several widely used basic color words with the aim of helping English learners know and use the idioms about color words better.
文摘Based on the theory of thematic complexity, a contrastive analysis on 2 sections selected from research articles-method and discussion, was conducted. The differences and similarities between the 2 sections in simple theme, multiple theme, textual theme, interpersonal theme, topical theme and thematic progression were analyzed and concluded. The author believes that the causes of the differences and similarities are the different genre features of the 2 sections and the academic features of the materials selected.
基金Projects(51405516,U1334208)supported by the National Natural Science Foundation of ChinaProject(2013GK2001)supported by the Science and Technology Program for Hunan Provincial Science and Technology Department,ChinaProject(2013zzts040)supported by the Graduate Degree Thesis Innovation Foundation of Central South University,China
文摘For the safety protection of passengers when train crashes occur, special structures are crucially needed as a kind of indispensable energy absorbing device. With the help of the structures, crash kinetic-energy can be completely absorbed or dissipated for the aim of safety. Two composite structures(circumscribed circle structure and inscribed circle structure) were constructed. In addition, comparison and optimization of the crashworthy characteristic of the two structures were carried out based on the method of explicit finite element analysis(FEA) and Kriging surrogate model. According to the result of Kriging surrogate model, conclusions can be safely drawn that the specific energy absorption(SEA) and ratio of specific energy absorption to initial peak force(REAF) of circumscribed circle structure are lager than those of inscribed circle structure under the same design parameters. In other words, circumscribed circle structure has better performances with higher energy-absorbing ability and lower initial peak force. Besides, error analysis was adopted and the result of which indicates that the Kriging surrogate model has high nonlinear fitting precision. What is more, the SEA and REAF optimum values of the two structures have been obtained through analysis, and the crushing results have been illustrated when the two structures reach optimum SEA and REAF.
文摘Once more to the lake is a representative work of the American Writer, Elwyn Brooks White, and has been acclaimed by people in the world. The paper offers a three-layered contrasting analysis of the essay. By detailed analysis of the contrasts running through the whole essay, the author finds that those contrasts are symbol of White's internal struggle and reflection for life.On the foundation of the three-layered contrasts, the paper presents the theme analysis and clarifies the content of the essay.
文摘[Objective] The research aimed to contrast parallel observation data of pressure and temperature in Qingxian station. [Method] By u- sing pressure and temperature observed by automatic station and artificial station in Qingxian from January of 2009 to December of 2010, compara- tive analysis of observation data was conducted, and formation reason of difference value was discussed. E Resultl Monthly average pressure differ- ence between automatic station and artificial observation value was from -0.7 to 0.1 hPa. Difference value of monthly average maximum pressure was from -0.5 to 0.4 hPa, while difference value of monthly average minimum pressure was from -0.7 to 0.2 hPa. Difference value of monthly extremely maximum pressure was from -0.3 to 0.6 hPa, while difference value of monthly extremely minimum pressure was from -1.1 to 0.1 hPa. Monthly average temperature difference value was from -2.0 to 0 ℃. Difference value of monthly average maximum temperature was from -0.4 to 0 ℃, while difference value of monthly average minimum temperature was from -0.1 to 0.2 ℃. Difference value of monthly extremely maximum temperature was from -0.3 to 0.3 ℃, while difference value of monthly extremely minimum temperature was from -0.3 to 0.3 ℃. [ Conclusion] Generation reason of observation difference mainly included differences of observation instrument and principle, differences of data collection time and method, different sensor installation positions and environments, manual intervention and observation error.
文摘I Introduction The fact that we are human beings who live together in society determines that much that we want to accomplish can be done only through social communication with other people. It is under
文摘Learning to handle hypothetical situations in a new language is always difficult(Catford,et al.,1974).This rule holds true for Moroccan Arabic(henceforth MA)speakers learning English because grammatical devices in the two languages differ in almost all equivalent situations.For instance,while English verb forms are used to indicate tense in conditional sentences,MA uses them to indicate aspect.Adopting the typology of conditional constructions suggested by Dancygier(1999)and Dancygier&Sweetser(2005),this study provides a contrastive analysis of conditionals in English and MA to predict the possible errors EFL/ESL learners are likely to make while learning English.The analysis shows that the main discrepancy between English conditionals and MA conditionals lies in the verb form used by the two systems.Accordingly,if EFL/ESL learners are influenced by verb form in their L1,they are likely to face some challenges while learning English conditionals.That is,they are likely to use the past tense in the protases of English predictive conditionals and generic conditionals since the perfective form of the verb is used in the protases of these two types in MA.Concerning the protases of English non-predictive conditionals,Moroccan EFL/ESL learners are likely to use either the past tense or the present tense since both the perfective and the imperfective forms of the verb are possible in the protases of MA non-predictive conditionals.However,due to the fact that the perfective form is the prototypical form in the protases of conditionals in MA,EFL/ESL learners are likely to use the past tense more often than the present tense.The analysis also shows that EFL/ESL learners tend to use the present tense in the apodoses of English conditionals since the prevalent form in the apodoses of MA conditionals is the imperfective.
文摘Based on ideational,interpersonal,and textual metafunctions in systemic functional linguistics(SFL),a contrastive analysis is carried out on two same-topic news reports of Chinese and American main stream media.Two reports from the People’s Daily and CNN are analyzed in terms of the lexical-grammatical systems(transitivity,mood and modality,and theme)realizing the three corresponding metafunctions to compare Chinese and American media reports on the same event.Results show that the two reports deploy different transitivity processes,but indicate similarity in the uses of mood and thematic choices.There are also respective preferences for reporting the sametopic news:CNN focuses on the whole process of the incident,the report being relatively objective and fair without obvious emotional bias,while the report of People’s Daily is relatively comprehensive,analyzing the incident from various angles,and playing a positive role in guiding public opinion.
文摘With the rapid development of the UHV power grid, evaluation of the economic and social benefits of the UHV power grid is conducive to guiding the planning and construction of UHV power grid. At present economic benefit evaluation system of the UHV power grid is driving to maturity stage on the whole at home and abroad, but it invariably tends to regard social benefits as part of economic benefits, without evaluating social benefit separately. The social benefit evaluation model of UHV power grid is built in case of sufficient investigation. The differentials between social benefit and social cost are calculated respectively by three kinds of solutions according to the constructed social cost evaluation index system and social benefits evaluation index system, conclusion that UHV power grid transmission has better social benefits can be reached by contrastively analyzing the social three kinds of solutions corresponding to benefits. At last, the evaluation model and method are verified and analyzed through the analysis of engineering projects.
文摘Back-translation is the translation of a translated text back into the language of the original text, which is an effective way to ensure accurate translation and assumes to be beneficial to improving learner＇s English competence. This thesis, based on the author＇s back translation training exercise, intends to make a constrastive study of source text in English and its back-translation precisely from the aspects of word choice, collocation, and sentence mechanics. Results have shown that by doing back-translation practice, the learners will strengthen their awareness of language differences between English and Chinese. Besides, as a special kind of translation, back-translation has its implications on English learning and Chinese-English translation, such as being a recitation method and testing tool.
文摘According to sociolinguistic research of speech events, the choice of linguistic forms is determined by the formality of the context and the relationship between interlocutors in a speech event. In this respect, address forms are socially driven phenomena which make the fundamental point in sociolinguistics clearly. The attempt of this study will be made to discuss the impact of the cultures, especially people in America and China. Mainly, the paper is pertinent to ask some questions： （1） whether there are any different pronouns of address used in different cultures, （2） the discrepancy of forms of address used in America and China and how interlocutors used them respectively and （3） are there any semantic systems presented in both two cultures based upon interlocutors＇ social position and cultural background.
文摘In this study, two comparative methods were selected to treat acute appendicitis, one is laparoscopic surgery, the other is open surgery, and two different surgical methods were used for clinical treatment. Methods: 72 patients with acute appendicitis in our hospital were analyzed and studied from March 2019 to August 2021. The patients were divided into open group and laparoscopic group, with 31 patients in each group. In the open group and the laparoscopic group, the former chose open appendectomy and the latter chose laparoscopic appendectomy. Results: in the time of recovery of gastrointestinal function, time of getting out of bed after operation, amount of blood loss during operation, operation time and incision, the effect of patients in open abdominal group was significantly lower than that of patients in laparoscopic group (P < 0.05). The incidence of complications in the laparoscopic group was significantly higher than that in the open group, such as postoperative wound infection, postpoisoning marks, intestinal obstruction, abdominal abscess, etc. the difference was statistically significant (P < 0.05). Conclusion: in the clinical comparative analysis of the treatment of patients with acute appendicitis, laparoscopic appendectomy can effectively reduce the blood loss during the operation, improve the patients' postoperative recovery ability, reduce the hospitalization time and shorten the postoperative excretion time. The analysis and research show that, in the treatment of patients with acute appendicitis analyzed by the two groups, laparoscopic surgery is more suitable for the treatment of patients with acute appendicitis, can effectively reduce the occurrence of complications, and is more effective than open surgery. After the recovery, it can also well reduce the incidence of complications, and has higher clinical application value, so as to help patients recover as soon as possible.
文摘Background:All neurons of the visual system exhibit response to differences in luminance.This neural response to visual contrast,also known as the contrast response function(CRF),follows a characteristic sigmoid shape that can be fitted with the Naka-Rushton equation.Four parameters define the CRF,and they are often used in different visual research disciplines,since they describe selective variations of neural responses.As novel technologies have grown,the capacity to record thousands of neurons simultaneously brings new challenges:processing and robustly analyzing larger amounts of data to maximize the outcomes of our experimental measurements.Nevertheless,current guidelines to fit neural activity based on the Naka-Rushton equation have been poorly discussed in depth.In this study,we explore several methods of boundary-setting and least-square curve-fitting for the CRF in order to avoid the pitfalls of blind curve-fitting.Furthermore,we intend to provide recommendations for experimenters to better prepare a solid quantification of CRF parameters that also minimize the time of the data acquisition.For this purpose,we have created a simplified theoretical model of spike-response dynamics,in which the firing rate of neurons is generated by a Poisson process.The spike trains generated by the theoretical model depending on visual contrast intensities were then fitted with the Naka-Rushton equation.This allowed us to identify combinations of parameters that were more important to adjust before performing experiments,to optimize the precision and efficiency of curve fitting(e.g.,boundaries of CRF parameters,number of trials,number of contrast tested,metric of contrast used and the effect of including multi-unit spikes into a single CRF,among others).Several goodness-of-fit methods were also examined in order to achieve ideal fits.With this approach,it is possible to anticipate the minimal requirements to gather and analyze data in a more efficient way in order to build stronger functional models.Methods:Spike-trains were randomly generated following a Poisson distribution in order to draw both an underlying theoretical curve and an empirical one.Random noise was added to the fit to simulate empirical conditions.The correlation function was recreated on the simulated data and re-fit using the Naka-Rushton equation.The two curves were compared:the idea being to determine the most advantageous boundaries and conditions for the curve-fit to be optimal.Statistical analysis was performed on the data to determine those conditions for experiments.Experiments were then conducted to acquire data from mice and cats to verify the model.Results:Results were obtained successfully and a model was proposed to assess the goodness of the fit of the contrast response function.Various parametres and their influence of the model were tested.Other similar models were proposed and their performance was assessed and compared to the previous ones.The fit was optimized to give semi-strict guidelines for scientists to follow in order to maximize their efficiency while obtaining the contrast tuning of a neuron.Conclusions:The aim of the study was to assess the optimal testing parametres of the neuronal response to visual gratings with various luminance,also called the CRF.As technology gets more powerful and potent,one must make choices when experimenting.With a strong model,robust boundaries,and strong experimental conditioning,the best fit to a function can lead to more efficient analysis and stronger cognitive models.
基金supported by the National Natural Science Foundation of China (Grant No. 51271125)
文摘The influence of temperatures on the stacking fault energies and deformation mechanism of a Re- containing single crystal nickel-based superalloy during creep at elevated temperatures was investigated by means of calculating the stacking fault energy of alloy, measuring creep properties and performing contrast analysis of dislocation configuration. The results show that the alloy at 760 ℃ possesses lower stacking fault energy, and the stacking fault of alloy increases with increasing temperature. The defor- mation mechanism of alloy during creep at 760 ℃ is 7＇ phase sheared by 〈110〉 super-dislocations, which may be decomposed to form the configuration of Shockley partials plus super-lattice intrinsic stacking fault, while the deformation mechanism of alloy during creep at 1070 ℃ is the screw or edge super- dislocations shearing into the rafted 7＇ phase. But during creep at 7（50 and 980 ℃, some super- dislocations shearing into 7＇ phase may cross-slip from the {111} to {100} planes to form the K-W locks with non-plane core structure, which may restrain the dislocations slipping to enhance the creep resis- tance of alloy at high temperature. The interaction between the Re and other elements may decrease the diffusion rate of atoms to improve the microstructure stability, which is thought to be the main reason why the K-W locks are to be kept in the Re-containing superalloy during creep at 980 ℃.
基金supported by NIH/NIA1R01AG 029681supported by the New Century Talent Program by the Ministry of Education of China,and Shanghai Shuguang Program(07SG13)supported by the China Scholarship Council.
文摘In this paper,a model-based reconstruction technique is proposed to simultaneously measure the relative deoxyhemoglobin concentration and the relative blood flow velocity in cerebral cortex.With the help of this model-based reconstruction technique,artifacts due to nonuniform laser illumination and curvature of cortex are efficiently corrected.The results of relative deoxyhemoglobin concentration and relative blood flow velocity are then used to detect and distinguish cerebral arteries and veins.In an experimental study on rat,cerebral blood vessels are segmented from the reconstructed blood flow image by Otsu multiple threshold method.Afterwards,arteries and veins are distinguished by a simple fuzzy criterion based on the information of relative deoxyhemoglobin concentration.
