Aim:To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods:Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. T...Aim:To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods:Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. The spermatozoa were frozen in straws by liquid nitrogen vapor using egg-yolk-free Tes-Tris (mTTE) synthetic extender and glycerol as cryoprotectant.The effects of glycerol concentration (1%,3 %,5 %,10 % and 15 % [v/v]) and its equilibration time (10 min,30 min,60 min and 90 min) on post-thaw spermatozoa were examined by sperm motility and sperm head membrane integrity.Results:The post-thaw motility and head membrane integrity of spermatozoa were significantly higher (P<0.05) for 5 % glycerol (42.95±2.55 and 50.39±2.42,respectively) than those of the other groups (1%:19.19±3.22 and 24.84±3.64;3 %:34.23±3.43 and 41.37±3.42;10 %: 15.68±2.36 and 21.39±3.14;15 %:7.47±1.44 and 12.90±2.18).The parameters for 30 min equilibration (42.95±2.55 and 50.39±2.42) were better (P<0.05) than those of the other groups (10 min:31.33±3.06 and 38. 98±3.31;60 min:32.49±3.86 and 40.01±4.18;90 min:31.16±3.66 and 38.30±3.78).Five percent glycerol and 30 min equilibration yielded the highest post-thaw sperm motility and head membrane integrity.Conclusion: Cynomolgus monkey spermatozoa can be successfully cryopreserved in a chemically defined extender,which is related to the concentration and the equilibration time of glycerol.展开更多
A general and versatile strategy to prepare melamine-formaldehyde(MF)microcapsules encapsulating oil-based fragrances by combining solvent evaporation and in situ polymerization was proposed in this work.The oil-based...A general and versatile strategy to prepare melamine-formaldehyde(MF)microcapsules encapsulating oil-based fragrances by combining solvent evaporation and in situ polymerization was proposed in this work.The oil-based fragrance was pre-encapsulated by an inner polyacrylate membrane via solvent evaporation,followed by in situ polymerization of MF precondensates as an outer shell.The polyacrylate membrane is used as an intermediate bridging layer to stabilize the oil-based fragrance,and to provide driving forces for in situ polymerization of MF precondensates through electrostatic attractions between carboxyl groups and ammonium ions.It was demonstrated that MF microcapsules containing clove oil were prepared successfully.The amount and the composition of the intermediate polyacrylate bridging layer were critical.Smooth and sphere-shaped MF-clove oil microcapsules were prepared when the weight ratio of polyacrylate to clove oil was over 60 wt%and the concentration of acrylic acid(AA)increased to 10 wt%in polyacrylate.In addition,MF microcapsules containing sunflower oil and hexyl salicylate were prepared by using this method.The work suggests that this new approach can be potentially used to encapsulate various core materials,tuning the shell properties of microcapsules such as thickness,mechanical strength and release properties.展开更多
This paper reports an efficient method of preparing porous polymeric microspheres by solvent evaporation in foam phase,in which phase separation between polymer and porogen occurs in foam phase instead of that in wate...This paper reports an efficient method of preparing porous polymeric microspheres by solvent evaporation in foam phase,in which phase separation between polymer and porogen occurs in foam phase instead of that in water phase by using the traditional solvent eva poration method.The method provides outstanding features,including being time-saving,of high-yield and able for continuous production,in which formation of porous polymeric microspheres finished within 3 min with a high production yield up to approximate 95 wt% and the process was able to be developed into a continuous process for production of porous polymeric microspheres.It was also universal to non-crosslinked polymers since the method is a development on the traditional emulsion solvent evaporation method.The new method is efficient and can be used potentially on the industrial scale for continuous production of porous polymeric microsphere s.展开更多
Noise artifacts are one of the key obstacles in applying continuous monitoring and computer-assisted analysis of lung sounds. Traditional adaptive noise cancellation (ANC) methodologies work reasonably well when signa...Noise artifacts are one of the key obstacles in applying continuous monitoring and computer-assisted analysis of lung sounds. Traditional adaptive noise cancellation (ANC) methodologies work reasonably well when signal and noise are stationary and independent. Clinical lung sound auscultation encounters an acoustic environment in which breath sounds are not stationary and often correlate with noise. Consequendy, capability of ANC becomes significantly compromised. This paper introduces a new methodology for extracting authentic lung sounds from noise-corrupted measurements. Unlike traditional noise cancellation methods that rely on either frequency band separation or signal/noise independence to achieve noise reduction, this methodology combines the traditional noise canceling methods with the unique feature of time-split stages in breathing sounds. By employing a multi-sensor system, the method first employs a high-pass filter to eliminate the off-band noise, and then performs time-shared blind identification and noise cancellation with recursion from breathing cycle to cycle. Since no frequency separation or signal/noise independence is required, this method potentially has a robust and reliable capability of noise reduction, complementing the traditional methods.展开更多
AIM: During emergency period, infectious diseases can be a major threat to military forces. During field training in southern China, diarrhea is the main cause of nonbattle injury. To evaluate the causes of and risk f...AIM: During emergency period, infectious diseases can be a major threat to military forces. During field training in southern China, diarrhea is the main cause of nonbattle injury. To evaluate the causes of and risk factors for diarrhea in emergency period, we collected clinical and epidemiological data from the People's Liberation Army (PLA) during fieldtraining in southern China. METHODS: From September 25 to October 2 1997, 2636 military personnel were investigated. Fecal sample cultures for lapactic pathogens were obtained from 103 military personnel with diarrhea. In addition, a questionnaire was administered to 103 cases and 206 controls to evaluate the association between illness and potential risk factors. At the same time,another questionnaire of 1:4 case-case control was administered to 22 severe cases (each severe case paired 4 mild cases). RESULTS: The training troop's diarrhea incidence rate was significantly higher than that of garrison. The diarrhea incidence rate of officers was significantly lower than that of soldiers. A lapactic pathogen was identified in 63.1% (65/103) of the troops with diarrhea. Enterotoxigenic Escherichia coli (35.0%) and plesiomona shigelloides (16.5%) were the most common bacterial pathogens. All bacterial isolates were sensitive to norfloxacin and ceftazidine. However, almost all of them were resistant to sulfamethoxazole, trimethoprim-sulfamethoxazole,oxytetracycline, doxycycline, furazolidone, ampicillin and cloromycetin to a different degree. Risk factors associated with diarrhea includediidrinking raw water, eating outside,contacting diarrhea patients, lacking sanitation, depression,lacking sleep, which were established by multiple-factor logistic regression analysis. In addition, the unit incidence rate was associated with the density of flies and the average daily boiled water available by regression and discriminate analysis. CONCLUSION: A series of risk factors are associated with the incidence rate of diarrhea. Our results may provide a useful basis for prevention and cure of diarrhea in emergency period of PLA.展开更多
Within the affine connection framework of Lagrangian control systems, basedon the results of Sussmann on small-time locally controllability of single-input affine nonlinearcontrol systems, the controllability results ...Within the affine connection framework of Lagrangian control systems, basedon the results of Sussmann on small-time locally controllability of single-input affine nonlinearcontrol systems, the controllability results for mechanical control systems with single-input areextended to the case of the systems with isotropic damping, where the Lagrangian is the kineticenergy associated with a Riemannian metric. A sufficient condition of negative small-time locallycontrollability for the system is obtained. Then,it is demonstrated that such systems are small-timelocally configuration controllable if and only if the dimension of the configuration manifold isone. Finally, two examples are given to illustrate the results. Lie bracketting of vector fields andthe symmetric product show the advantages in the discussion.展开更多
This paper presents a novel approach to detect and diagnose faults in the dynamic part of a class of stochastic systems . the Such a group of systems are subjected to a set of crisp inputs but the outputs considered a...This paper presents a novel approach to detect and diagnose faults in the dynamic part of a class of stochastic systems . the Such a group of systems are subjected to a set of crisp inputs but the outputs considered are the measurable probability density functions (PDFs) of the system output, rather than the system output alone. A new approximation model is developed for the output probability density functions so that the dynamic part of the system is decoupled from the output probability density functions. A nonlinear adaptive observer is constructed to detect and diagnose the fault in the dynamic part of the system. Conver-gency analysis is performed for the error dynamics raised from the fault detection and diagnosis phase and an applicability study on the detection and diagnosis of the unexpected changes in the 2D grammage distributions in a paper forming process is included.展开更多
The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equat...The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equatorial view and is three-lobed circular in the polar view. Pollen grains are usually radially symmetrical, isopolar, tricolporate or syntricolporate, with reticulate sculpture. The pollen characteristics among species are fairly similar to each other. Morphological information regarding the pollen grains shows that Parnassia is a natural genus. Based on exine ornamentation observed under SEM, three types of pollen grains were recognized: (i) type I, with foveolate-reticulate sculpture; (ii) type II, with a finely reticulate sculpture; and (iii) type III, with a coarsely reticulate sculpture. Most sections of this genus have one type of sculpture of pollen morphology, but Sect. Nectarotrilobos has three types of sculpture and Sect. Saxifragastrum has two types of sculpture. All three types of sculpture can be found in Southwest China, with species with the longest (Parnassia delavayi Franch.) and shortest (Parnassia faberi Oliv.) colpi, implying that Southwest China is the center of diversification of the genus.展开更多
文摘Aim:To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods:Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. The spermatozoa were frozen in straws by liquid nitrogen vapor using egg-yolk-free Tes-Tris (mTTE) synthetic extender and glycerol as cryoprotectant.The effects of glycerol concentration (1%,3 %,5 %,10 % and 15 % [v/v]) and its equilibration time (10 min,30 min,60 min and 90 min) on post-thaw spermatozoa were examined by sperm motility and sperm head membrane integrity.Results:The post-thaw motility and head membrane integrity of spermatozoa were significantly higher (P<0.05) for 5 % glycerol (42.95±2.55 and 50.39±2.42,respectively) than those of the other groups (1%:19.19±3.22 and 24.84±3.64;3 %:34.23±3.43 and 41.37±3.42;10 %: 15.68±2.36 and 21.39±3.14;15 %:7.47±1.44 and 12.90±2.18).The parameters for 30 min equilibration (42.95±2.55 and 50.39±2.42) were better (P<0.05) than those of the other groups (10 min:31.33±3.06 and 38. 98±3.31;60 min:32.49±3.86 and 40.01±4.18;90 min:31.16±3.66 and 38.30±3.78).Five percent glycerol and 30 min equilibration yielded the highest post-thaw sperm motility and head membrane integrity.Conclusion: Cynomolgus monkey spermatozoa can be successfully cryopreserved in a chemically defined extender,which is related to the concentration and the equilibration time of glycerol.
基金Supported by the National Natural Science Foundation of China(21466016,21577053)the Natural Science Foundation of Yunnan Province(2016FB024).
文摘A general and versatile strategy to prepare melamine-formaldehyde(MF)microcapsules encapsulating oil-based fragrances by combining solvent evaporation and in situ polymerization was proposed in this work.The oil-based fragrance was pre-encapsulated by an inner polyacrylate membrane via solvent evaporation,followed by in situ polymerization of MF precondensates as an outer shell.The polyacrylate membrane is used as an intermediate bridging layer to stabilize the oil-based fragrance,and to provide driving forces for in situ polymerization of MF precondensates through electrostatic attractions between carboxyl groups and ammonium ions.It was demonstrated that MF microcapsules containing clove oil were prepared successfully.The amount and the composition of the intermediate polyacrylate bridging layer were critical.Smooth and sphere-shaped MF-clove oil microcapsules were prepared when the weight ratio of polyacrylate to clove oil was over 60 wt%and the concentration of acrylic acid(AA)increased to 10 wt%in polyacrylate.In addition,MF microcapsules containing sunflower oil and hexyl salicylate were prepared by using this method.The work suggests that this new approach can be potentially used to encapsulate various core materials,tuning the shell properties of microcapsules such as thickness,mechanical strength and release properties.
基金financially supported by National Natural Science Foundation of China (22068018, 21466016 and 51863011)Natural Science Foundation of Yunnan Province (2016FB024)Yunnan Ten Thousand Talents Plan Young & Elite Talents Project。
文摘This paper reports an efficient method of preparing porous polymeric microspheres by solvent evaporation in foam phase,in which phase separation between polymer and porogen occurs in foam phase instead of that in water phase by using the traditional solvent eva poration method.The method provides outstanding features,including being time-saving,of high-yield and able for continuous production,in which formation of porous polymeric microspheres finished within 3 min with a high production yield up to approximate 95 wt% and the process was able to be developed into a continuous process for production of porous polymeric microspheres.It was also universal to non-crosslinked polymers since the method is a development on the traditional emulsion solvent evaporation method.The new method is efficient and can be used potentially on the industrial scale for continuous production of porous polymeric microsphere s.
基金Hong Wang's research was supported in part by the Anesthesiology Department at Wayne State University and in part by Wayne State University Research Enhancement ProgramLeyi Wang" s research was supported in part by the National Science Foundation ( No.
文摘Noise artifacts are one of the key obstacles in applying continuous monitoring and computer-assisted analysis of lung sounds. Traditional adaptive noise cancellation (ANC) methodologies work reasonably well when signal and noise are stationary and independent. Clinical lung sound auscultation encounters an acoustic environment in which breath sounds are not stationary and often correlate with noise. Consequendy, capability of ANC becomes significantly compromised. This paper introduces a new methodology for extracting authentic lung sounds from noise-corrupted measurements. Unlike traditional noise cancellation methods that rely on either frequency band separation or signal/noise independence to achieve noise reduction, this methodology combines the traditional noise canceling methods with the unique feature of time-split stages in breathing sounds. By employing a multi-sensor system, the method first employs a high-pass filter to eliminate the off-band noise, and then performs time-shared blind identification and noise cancellation with recursion from breathing cycle to cycle. Since no frequency separation or signal/noise independence is required, this method potentially has a robust and reliable capability of noise reduction, complementing the traditional methods.
基金Supported by the Key Program of Military Medical ScienceTechnique Foundation during the 9~(th)-Five Year Plan Period
文摘AIM: During emergency period, infectious diseases can be a major threat to military forces. During field training in southern China, diarrhea is the main cause of nonbattle injury. To evaluate the causes of and risk factors for diarrhea in emergency period, we collected clinical and epidemiological data from the People's Liberation Army (PLA) during fieldtraining in southern China. METHODS: From September 25 to October 2 1997, 2636 military personnel were investigated. Fecal sample cultures for lapactic pathogens were obtained from 103 military personnel with diarrhea. In addition, a questionnaire was administered to 103 cases and 206 controls to evaluate the association between illness and potential risk factors. At the same time,another questionnaire of 1:4 case-case control was administered to 22 severe cases (each severe case paired 4 mild cases). RESULTS: The training troop's diarrhea incidence rate was significantly higher than that of garrison. The diarrhea incidence rate of officers was significantly lower than that of soldiers. A lapactic pathogen was identified in 63.1% (65/103) of the troops with diarrhea. Enterotoxigenic Escherichia coli (35.0%) and plesiomona shigelloides (16.5%) were the most common bacterial pathogens. All bacterial isolates were sensitive to norfloxacin and ceftazidine. However, almost all of them were resistant to sulfamethoxazole, trimethoprim-sulfamethoxazole,oxytetracycline, doxycycline, furazolidone, ampicillin and cloromycetin to a different degree. Risk factors associated with diarrhea includediidrinking raw water, eating outside,contacting diarrhea patients, lacking sanitation, depression,lacking sleep, which were established by multiple-factor logistic regression analysis. In addition, the unit incidence rate was associated with the density of flies and the average daily boiled water available by regression and discriminate analysis. CONCLUSION: A series of risk factors are associated with the incidence rate of diarrhea. Our results may provide a useful basis for prevention and cure of diarrhea in emergency period of PLA.
文摘Within the affine connection framework of Lagrangian control systems, basedon the results of Sussmann on small-time locally controllability of single-input affine nonlinearcontrol systems, the controllability results for mechanical control systems with single-input areextended to the case of the systems with isotropic damping, where the Lagrangian is the kineticenergy associated with a Riemannian metric. A sufficient condition of negative small-time locallycontrollability for the system is obtained. Then,it is demonstrated that such systems are small-timelocally configuration controllable if and only if the dimension of the configuration manifold isone. Finally, two examples are given to illustrate the results. Lie bracketting of vector fields andthe symmetric product show the advantages in the discussion.
文摘This paper presents a novel approach to detect and diagnose faults in the dynamic part of a class of stochastic systems . the Such a group of systems are subjected to a set of crisp inputs but the outputs considered are the measurable probability density functions (PDFs) of the system output, rather than the system output alone. A new approximation model is developed for the output probability density functions so that the dynamic part of the system is decoupled from the output probability density functions. A nonlinear adaptive observer is constructed to detect and diagnose the fault in the dynamic part of the system. Conver-gency analysis is performed for the error dynamics raised from the fault detection and diagnosis phase and an applicability study on the detection and diagnosis of the unexpected changes in the 2D grammage distributions in a paper forming process is included.
文摘The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equatorial view and is three-lobed circular in the polar view. Pollen grains are usually radially symmetrical, isopolar, tricolporate or syntricolporate, with reticulate sculpture. The pollen characteristics among species are fairly similar to each other. Morphological information regarding the pollen grains shows that Parnassia is a natural genus. Based on exine ornamentation observed under SEM, three types of pollen grains were recognized: (i) type I, with foveolate-reticulate sculpture; (ii) type II, with a finely reticulate sculpture; and (iii) type III, with a coarsely reticulate sculpture. Most sections of this genus have one type of sculpture of pollen morphology, but Sect. Nectarotrilobos has three types of sculpture and Sect. Saxifragastrum has two types of sculpture. All three types of sculpture can be found in Southwest China, with species with the longest (Parnassia delavayi Franch.) and shortest (Parnassia faberi Oliv.) colpi, implying that Southwest China is the center of diversification of the genus.