Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three...Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three-line stedle lines and 27 restoring lines(cultivars) commonly culti- vated in Central China region were regarded as expadmental materials to conduct 4 x27NCII cross design, and the grain characters of three-line hybrid rico were analyzed at genetic and correlation levels. [ Result] Four characters of grain length, grain width, 1 000-grain weight and length- width ratio play the leading role in additive gene effect; these four characters were simultaneously influenced by male parent and female parent, but the effect from male parent was relatively larger. The grain length, grain width, 1 000-grain weight and length-width ratio all have high brood hedtabUities( respectively 99.65%, 98.31%, 95.27% and 98.81% ). Correlation analysis showed that grain length was positively correlated with 1 000-grain weight and length-width ratio at extremely significant level; 1 000-grain weight was positively correlated with grain length and length- width ratio at extremely significant level, and was insignificantly correlated with grain width; grain width was negatively correlated with grain length and length-width ratio at extremely significant level. Path analysis showed that the direct path coefficients of grain length, grain width and 1 0(30- grain weight to length-width ratio were 0.624 6, -0.555 9 and -0.015 8, respectively. [ Conclusion] This study systematically analyzed the effects of stedle line and restoring line on grain characters of hybrid rice, which provided theoretical basis for breeding high quality and yield hy- brid dce.展开更多
This paper described the whole process of three line hybrid pepper seed production in detail, including requirement of the seed production base, parent culti- vation, field management, and specified the key operation ...This paper described the whole process of three line hybrid pepper seed production in detail, including requirement of the seed production base, parent culti- vation, field management, and specified the key operation techniques in seed pro- duction, such as parental impurity removal to preserve pure state, pollen collection, pollination and seed collecting essentials. This specification is of guiding significance for the production of hybrid pepper seed and ensuring the purity of hybrid pepper seed.展开更多
Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical metho...Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical methods. The results showed that dominance effects were predominant for TN. The expression of those additive effects were affected by environment and genotype interaction, but the expression of dominance effects were not affected. Heterosis was the strongest in the middle developmental periods of TN. Additive effects and dominance effects were selectively expressed throughout in the entire tillering developmental stage. Analysis of genetic correlation between TN at different stages and the productive panicles indicated that a close correlation appeared earlier in the populations with higher heterosis than in those with less heterosis. Utilization of heterosis at the middle tillering stage might enhance the final biomass but reduce the percentage of productive panicles.展开更多
This paper presents a novel vision based localization algorithm from three-line structure ( TLS) .Two types of TLS are investigated: 1) three parallel lines ( Structure I) ; 2) two parallel lines and one orthogonal li...This paper presents a novel vision based localization algorithm from three-line structure ( TLS) .Two types of TLS are investigated: 1) three parallel lines ( Structure I) ; 2) two parallel lines and one orthogonal line ( Structure II) .From single image of either structure,the camera pose can be uniquely computed for vision localization.Contributions of this paper are as follows: 1 ) both TLS structures can be used as simple and practical landmarks,which are widely available in daily life; 2) the proposed algorithm complements existing localization methods,which usually use complex landmarks,especially in the partial blockage conditions; 3) compared with the general Perspective-3-Lines ( P3L) problem,camera pose can be uniquely computed from either structure.The proposed algorithm has been tested with both simulation and real image data.For a typical simulated indoor condition ( 75 cm-size landmark,less than 7.0 m landmark-to-camera distance,and 0.5-pixel image noises) ,the means of localization errors from Structure I and Structure II are less than 3.0 cm.And the standard deviations are less than 3.0 cm and 1.5 cm,respectively.The algorithm is further validated with two actual image experiments.Within a 7.5 m × 7.5 m indoor situation,the overall relative localization errors from Structure I and Structure II are less than 2.2% and 2.3% ,respectively,with about 6.0 m distance.The results demonstrate that the algorithm works well for practical vision localization.展开更多
To enhance the image motion compensation accuracy of off-axis three-mirror anastigmatic( TMA)three-line array aerospace mapping cameras,a new method of image motion velocity field modeling is proposed in this paper. F...To enhance the image motion compensation accuracy of off-axis three-mirror anastigmatic( TMA)three-line array aerospace mapping cameras,a new method of image motion velocity field modeling is proposed in this paper. Firstly,based on the imaging principle of mapping cameras,an analytical expression of image motion velocity of off-axis TMA three-line array aerospace mapping cameras is deduced from different coordinate systems we established and the attitude dynamics principle. Then,the case of a three-line array mapping camera is studied,in which the simulation of the focal plane image motion velocity fields of the forward-view camera,the nadir-view camera and the backward-view camera are carried out,and the optimization schemes for image motion velocity matching and drift angle matching are formulated according the simulation results. Finally,this method is verified with a dynamic imaging experimental system. The results are indicative of that when image motion compensation for nadir-view camera is conducted using the proposed image motion velocity field model,the line pair of target images at Nyquist frequency is clear and distinguishable. Under the constraint that modulation transfer function( MTF) reduces by 5%,when the horizontal frequencies of the forward-view camera and the backward-view camera are adjusted uniformly according to the proposed image motion velocity matching scheme,the time delay integration( TDI) stages reach 6 at most. When the TDI stages are more than 6,the three groups of camera will independently undergo horizontal frequency adjustment. However, when the proposed drift angle matching scheme is adopted for uniform drift angle adjustment,the number of TDI stages will not exceed 81. The experimental results have demonstrated the validity and accuracy of the proposed image motion velocity field model and matching optimization scheme,providing reliable basis for on-orbit image motion compensation of aerospace mapping cameras.展开更多
The hook formation mechanism in continuously cast slabs of ultra-low carbon steel was analyzed in detail through numerical calculations and experimental observations using optical microscopy,and its distribution chara...The hook formation mechanism in continuously cast slabs of ultra-low carbon steel was analyzed in detail through numerical calculations and experimental observations using optical microscopy,and its distribution characteristics were determined.Numerical simulations confirmed that the freezing–overflow mechanism is the primary cause of hook formation.They also revealed that the freezing event occurs unpredictably,while the overflow event takes place during the positive strip time.The average pitch of oscillation marks(OMs)on the slab surface was 8.693 mm,while the theoretical pitch was 8.889 mm,with a difference of approximately 2%.This discrepancy primarily results from varying degrees of overflow,which affects the morphology of the OMs and the positions of their deepest points.Notably,this result further confirmed that the freezing and overflow in the meniscus were indeed caused by the periodic oscillation of the mold.Higher superheat hindered hook formation,leading to a negative correlation between the hook depth distribution around the slab and the temperature distribution within the mold.Therefore,the depth of the corner hook was greater than that of other positions,which was caused by the intensified cooling effect of the corner.Moreover,key factors influencing hook development were analyzed,providing insights into transient fluid flow and heat transfer characteristics within the mold.Transient fluid flow and heat transfer contributed to the randomness and tendency of hook formation.This randomness was reflected in the varying angles of the hooks,whereas the tendency was evident in the negative correlation between superheat and hook length.Based on the randomness and tendency of hook formation and its profile characteristics,a new method for controlling hook depth based on“sine law”is proposed.展开更多
BACKGROUND Hook of hamate fractures occur either due to repetitive stress from gripping sports(e.g.,golf,tennis,and baseball),leading to fatigue fracture,or as a result of trauma from falls or other injuries.The recom...BACKGROUND Hook of hamate fractures occur either due to repetitive stress from gripping sports(e.g.,golf,tennis,and baseball),leading to fatigue fracture,or as a result of trauma from falls or other injuries.The recommended treatment involves the excision of bone fragments to facilitate athletes’early return to sports;excision surgery is also performed in trauma cases.However,some patients prefer nonsurgical treatment options,and conservative treatment should be considered.AIM To present a case series of 16 patients conservatively treated for hook of hamate fractures.METHODS This study included 16(11 males and 5 females;right side,6 cases;left side,10)patients who desired conservative treatment and could be followed-up until bone union was achieved.The average age of the patients was 49.6(range:24-72)years.The average time from injury to consultation was 4.3(range:0.2-21.4)weeks.The treatment involved 4 weeks of casting from the forearm to the metacarpophalangeal joint,followed by 8 weeks of splint fixation of the wrist.Follow-up computed tomography scans were performed every 4 weeks.RESULTS Bone union was achieved in all patients.The average duration of casting was 3.7(range:0-5)weeks and that of splint fixation thereafter was 8.6(range:0-28)weeks.The patients did not exhibit joint contractures or range of motion restrictions due to prolonged immobilization.CONCLUSION Conservative treatment with external fixation may be an option for hook of hamate fractures.展开更多
This editorial critically evaluates the landmark study by Tanaka and Yoshii,which demonstrated a 100%union rate with conservative management of hamate hook fractures,challenging the historical preference for surgical ...This editorial critically evaluates the landmark study by Tanaka and Yoshii,which demonstrated a 100%union rate with conservative management of hamate hook fractures,challenging the historical preference for surgical intervention.In contrast to Scheufle et al’s report of 90%-100%failure rates with early surgical approaches,Tanaka and Yoshii’s protocol achieved universal healing despite delayed diagnoses in 25%of cases.Central to this success is the systematic inte-gration of high-resolution computed tomography for early diagnosis and dynamic monitoring of trabecular bone regeneration,significantly reducing missed dia-gnoses and guiding personalized immobilization timelines.The patient-centered strategy—allowing temporary splint removal during low-risk activities—balanced fracture stability with joint mobility preservation,avoiding post-treatment stiff-ness.However,limitations such as small sample size(n=16),selection bias,and insufficient long-term functional data(e.g.,grip strength,return-to-sport metrics)underscore the need for comparative trials.Emerging trends,including adjunct therapies like low-intensity pulsed ultrasound and biologics(e.g.,teriparatide),are proposed to accelerate healing while minimizing immobilization risks.This work redefines conservative fracture management paradigms,emphasizing in-novation without compromising efficacy.Overall,this assessment deepens our understanding of the conservative management of hook fractures and provides evidence-based insights for improved clinical decision-making.展开更多
During the continuous casting process of low carbon steel,the solidified hook formed in the mold has great effects on the surface quality of the cast slab.Some factory experiments have been conducted to investigate th...During the continuous casting process of low carbon steel,the solidified hook formed in the mold has great effects on the surface quality of the cast slab.Some factory experiments have been conducted to investigate the microscopic characteristics and reveal the influence of process parameters on solidified hooks.The depth of the hooks showed a positive correlation with the deflection angle,length,and oscillation mark(OM)depth,which indicates that the OM depth can serve as an approximate indicator for evaluating the depth of the solidified hooks.On the wide and narrow faces of the cast slab,the depth of the solidified hooks and the temperature distribution in the mold show opposite trends,with lower depths of solidified hooks at positions with higher temperatures.In addition,the influence of process parameters on solidified hooks was analyzed.With the increase in superheat,not only the depth of solidified hooks gradually decreases,but also the ratio of depression-typed marks increases.Increasing casting speed and decreasing immersion depth of the submerged entry nozzle will both lead to a decrease in the depth of the solidified hook.展开更多
Objective:To evaluate the therapeutic effect of dynamic fixation with a hook plate-double loop plate internal fixation system for high-energy acromioclavicular joint complex dislocation(denoted as HACD,i.e.,Rockwood t...Objective:To evaluate the therapeutic effect of dynamic fixation with a hook plate-double loop plate internal fixation system for high-energy acromioclavicular joint complex dislocation(denoted as HACD,i.e.,Rockwood type III-V dislocation).Methods:Fifty-eight patients with HACD were selected and evenly divided by drawing lots.The experimental group underwent ligament reconstruction treatment,while the reference group received hook plate fixation treatment.The efficacy and other indicators were compared between the groups.Results:The overall effective rates between the groups were similar(P>0.05).The experimental group had a longer surgical duration,lower pain scores at 6 months postoperatively,higher shoulder joint function scores,and a lower complication rate,with P<0.05 when compared between groups.Conclusion:The effectiveness of the double loop plate internal fixation system ligament reconstruction treatment for patients with HACD is comparable to that of hook plate fixation treatment.Although the surgical duration is slightly longer,postoperative pain is milder,facilitating the recovery of shoulder joint function in patients and offering higher safety.展开更多
文摘Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three-line stedle lines and 27 restoring lines(cultivars) commonly culti- vated in Central China region were regarded as expadmental materials to conduct 4 x27NCII cross design, and the grain characters of three-line hybrid rico were analyzed at genetic and correlation levels. [ Result] Four characters of grain length, grain width, 1 000-grain weight and length- width ratio play the leading role in additive gene effect; these four characters were simultaneously influenced by male parent and female parent, but the effect from male parent was relatively larger. The grain length, grain width, 1 000-grain weight and length-width ratio all have high brood hedtabUities( respectively 99.65%, 98.31%, 95.27% and 98.81% ). Correlation analysis showed that grain length was positively correlated with 1 000-grain weight and length-width ratio at extremely significant level; 1 000-grain weight was positively correlated with grain length and length- width ratio at extremely significant level, and was insignificantly correlated with grain width; grain width was negatively correlated with grain length and length-width ratio at extremely significant level. Path analysis showed that the direct path coefficients of grain length, grain width and 1 0(30- grain weight to length-width ratio were 0.624 6, -0.555 9 and -0.015 8, respectively. [ Conclusion] This study systematically analyzed the effects of stedle line and restoring line on grain characters of hybrid rice, which provided theoretical basis for breeding high quality and yield hy- brid dce.
基金Supported by the Planning Subject of"the Twelfth Five-Year-Plan"in National Science and Technology for the Rural Development in China(2011BAD35B07)the Job Subsidies for the Experts in Staple Vegetable Breeding of Vegetable Industry of Hunan Province+1 种基金the"the Twelfth Five-Year-Plan"of National Science and Technology Support Plan(2012BAD02B02)the Special Fund for Agro-Scientific Research in Public Interest(201303028)~~
文摘This paper described the whole process of three line hybrid pepper seed production in detail, including requirement of the seed production base, parent culti- vation, field management, and specified the key operation techniques in seed pro- duction, such as parental impurity removal to preserve pure state, pollen collection, pollination and seed collecting essentials. This specification is of guiding significance for the production of hybrid pepper seed and ensuring the purity of hybrid pepper seed.
文摘Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical methods. The results showed that dominance effects were predominant for TN. The expression of those additive effects were affected by environment and genotype interaction, but the expression of dominance effects were not affected. Heterosis was the strongest in the middle developmental periods of TN. Additive effects and dominance effects were selectively expressed throughout in the entire tillering developmental stage. Analysis of genetic correlation between TN at different stages and the productive panicles indicated that a close correlation appeared earlier in the populations with higher heterosis than in those with less heterosis. Utilization of heterosis at the middle tillering stage might enhance the final biomass but reduce the percentage of productive panicles.
基金Sponsored by the National Natural Science Foundation of China (Grant No. 51208168)the Research Grant from the Department of Education of Liaoning Province (Grant No. L2010060)
文摘This paper presents a novel vision based localization algorithm from three-line structure ( TLS) .Two types of TLS are investigated: 1) three parallel lines ( Structure I) ; 2) two parallel lines and one orthogonal line ( Structure II) .From single image of either structure,the camera pose can be uniquely computed for vision localization.Contributions of this paper are as follows: 1 ) both TLS structures can be used as simple and practical landmarks,which are widely available in daily life; 2) the proposed algorithm complements existing localization methods,which usually use complex landmarks,especially in the partial blockage conditions; 3) compared with the general Perspective-3-Lines ( P3L) problem,camera pose can be uniquely computed from either structure.The proposed algorithm has been tested with both simulation and real image data.For a typical simulated indoor condition ( 75 cm-size landmark,less than 7.0 m landmark-to-camera distance,and 0.5-pixel image noises) ,the means of localization errors from Structure I and Structure II are less than 3.0 cm.And the standard deviations are less than 3.0 cm and 1.5 cm,respectively.The algorithm is further validated with two actual image experiments.Within a 7.5 m × 7.5 m indoor situation,the overall relative localization errors from Structure I and Structure II are less than 2.2% and 2.3% ,respectively,with about 6.0 m distance.The results demonstrate that the algorithm works well for practical vision localization.
基金Sponsored by the National High Technology Research and Development Program of China(Grant No.863-2-5-1-13B)the Jilin Province Science and Technology Development Plan Item(Grant No.20130522107JH)
文摘To enhance the image motion compensation accuracy of off-axis three-mirror anastigmatic( TMA)three-line array aerospace mapping cameras,a new method of image motion velocity field modeling is proposed in this paper. Firstly,based on the imaging principle of mapping cameras,an analytical expression of image motion velocity of off-axis TMA three-line array aerospace mapping cameras is deduced from different coordinate systems we established and the attitude dynamics principle. Then,the case of a three-line array mapping camera is studied,in which the simulation of the focal plane image motion velocity fields of the forward-view camera,the nadir-view camera and the backward-view camera are carried out,and the optimization schemes for image motion velocity matching and drift angle matching are formulated according the simulation results. Finally,this method is verified with a dynamic imaging experimental system. The results are indicative of that when image motion compensation for nadir-view camera is conducted using the proposed image motion velocity field model,the line pair of target images at Nyquist frequency is clear and distinguishable. Under the constraint that modulation transfer function( MTF) reduces by 5%,when the horizontal frequencies of the forward-view camera and the backward-view camera are adjusted uniformly according to the proposed image motion velocity matching scheme,the time delay integration( TDI) stages reach 6 at most. When the TDI stages are more than 6,the three groups of camera will independently undergo horizontal frequency adjustment. However, when the proposed drift angle matching scheme is adopted for uniform drift angle adjustment,the number of TDI stages will not exceed 81. The experimental results have demonstrated the validity and accuracy of the proposed image motion velocity field model and matching optimization scheme,providing reliable basis for on-orbit image motion compensation of aerospace mapping cameras.
基金financially supported by the National Natural Science Foundation of China(No.52174306)the Fundamental Research Funds for the Central Universities(Nos.N2225023 and N2425006)the Basic Research Projects of Liaoning Provincial Department of Education(No.LJ212410148027)。
文摘The hook formation mechanism in continuously cast slabs of ultra-low carbon steel was analyzed in detail through numerical calculations and experimental observations using optical microscopy,and its distribution characteristics were determined.Numerical simulations confirmed that the freezing–overflow mechanism is the primary cause of hook formation.They also revealed that the freezing event occurs unpredictably,while the overflow event takes place during the positive strip time.The average pitch of oscillation marks(OMs)on the slab surface was 8.693 mm,while the theoretical pitch was 8.889 mm,with a difference of approximately 2%.This discrepancy primarily results from varying degrees of overflow,which affects the morphology of the OMs and the positions of their deepest points.Notably,this result further confirmed that the freezing and overflow in the meniscus were indeed caused by the periodic oscillation of the mold.Higher superheat hindered hook formation,leading to a negative correlation between the hook depth distribution around the slab and the temperature distribution within the mold.Therefore,the depth of the corner hook was greater than that of other positions,which was caused by the intensified cooling effect of the corner.Moreover,key factors influencing hook development were analyzed,providing insights into transient fluid flow and heat transfer characteristics within the mold.Transient fluid flow and heat transfer contributed to the randomness and tendency of hook formation.This randomness was reflected in the varying angles of the hooks,whereas the tendency was evident in the negative correlation between superheat and hook length.Based on the randomness and tendency of hook formation and its profile characteristics,a new method for controlling hook depth based on“sine law”is proposed.
文摘BACKGROUND Hook of hamate fractures occur either due to repetitive stress from gripping sports(e.g.,golf,tennis,and baseball),leading to fatigue fracture,or as a result of trauma from falls or other injuries.The recommended treatment involves the excision of bone fragments to facilitate athletes’early return to sports;excision surgery is also performed in trauma cases.However,some patients prefer nonsurgical treatment options,and conservative treatment should be considered.AIM To present a case series of 16 patients conservatively treated for hook of hamate fractures.METHODS This study included 16(11 males and 5 females;right side,6 cases;left side,10)patients who desired conservative treatment and could be followed-up until bone union was achieved.The average age of the patients was 49.6(range:24-72)years.The average time from injury to consultation was 4.3(range:0.2-21.4)weeks.The treatment involved 4 weeks of casting from the forearm to the metacarpophalangeal joint,followed by 8 weeks of splint fixation of the wrist.Follow-up computed tomography scans were performed every 4 weeks.RESULTS Bone union was achieved in all patients.The average duration of casting was 3.7(range:0-5)weeks and that of splint fixation thereafter was 8.6(range:0-28)weeks.The patients did not exhibit joint contractures or range of motion restrictions due to prolonged immobilization.CONCLUSION Conservative treatment with external fixation may be an option for hook of hamate fractures.
文摘This editorial critically evaluates the landmark study by Tanaka and Yoshii,which demonstrated a 100%union rate with conservative management of hamate hook fractures,challenging the historical preference for surgical intervention.In contrast to Scheufle et al’s report of 90%-100%failure rates with early surgical approaches,Tanaka and Yoshii’s protocol achieved universal healing despite delayed diagnoses in 25%of cases.Central to this success is the systematic inte-gration of high-resolution computed tomography for early diagnosis and dynamic monitoring of trabecular bone regeneration,significantly reducing missed dia-gnoses and guiding personalized immobilization timelines.The patient-centered strategy—allowing temporary splint removal during low-risk activities—balanced fracture stability with joint mobility preservation,avoiding post-treatment stiff-ness.However,limitations such as small sample size(n=16),selection bias,and insufficient long-term functional data(e.g.,grip strength,return-to-sport metrics)underscore the need for comparative trials.Emerging trends,including adjunct therapies like low-intensity pulsed ultrasound and biologics(e.g.,teriparatide),are proposed to accelerate healing while minimizing immobilization risks.This work redefines conservative fracture management paradigms,emphasizing in-novation without compromising efficacy.Overall,this assessment deepens our understanding of the conservative management of hook fractures and provides evidence-based insights for improved clinical decision-making.
基金the financial support of National Key Research and Development Plan(No.2021YFB3702000)National Natural Science of China(Nos.52074076,52174306 and U20A20272)Fundamental Research Funds for the Central Universities(Nos.N2225023 and N2425006).Author information。
文摘During the continuous casting process of low carbon steel,the solidified hook formed in the mold has great effects on the surface quality of the cast slab.Some factory experiments have been conducted to investigate the microscopic characteristics and reveal the influence of process parameters on solidified hooks.The depth of the hooks showed a positive correlation with the deflection angle,length,and oscillation mark(OM)depth,which indicates that the OM depth can serve as an approximate indicator for evaluating the depth of the solidified hooks.On the wide and narrow faces of the cast slab,the depth of the solidified hooks and the temperature distribution in the mold show opposite trends,with lower depths of solidified hooks at positions with higher temperatures.In addition,the influence of process parameters on solidified hooks was analyzed.With the increase in superheat,not only the depth of solidified hooks gradually decreases,but also the ratio of depression-typed marks increases.Increasing casting speed and decreasing immersion depth of the submerged entry nozzle will both lead to a decrease in the depth of the solidified hook.
文摘Objective:To evaluate the therapeutic effect of dynamic fixation with a hook plate-double loop plate internal fixation system for high-energy acromioclavicular joint complex dislocation(denoted as HACD,i.e.,Rockwood type III-V dislocation).Methods:Fifty-eight patients with HACD were selected and evenly divided by drawing lots.The experimental group underwent ligament reconstruction treatment,while the reference group received hook plate fixation treatment.The efficacy and other indicators were compared between the groups.Results:The overall effective rates between the groups were similar(P>0.05).The experimental group had a longer surgical duration,lower pain scores at 6 months postoperatively,higher shoulder joint function scores,and a lower complication rate,with P<0.05 when compared between groups.Conclusion:The effectiveness of the double loop plate internal fixation system ligament reconstruction treatment for patients with HACD is comparable to that of hook plate fixation treatment.Although the surgical duration is slightly longer,postoperative pain is milder,facilitating the recovery of shoulder joint function in patients and offering higher safety.