To identify suitable grass species for growth in the Jianghan Plain,the micromorphologies of the upper and lower epidermis of the leaves of 14 bermudagrass varieties of Cynodon dactylon were investigated,and the numbe...To identify suitable grass species for growth in the Jianghan Plain,the micromorphologies of the upper and lower epidermis of the leaves of 14 bermudagrass varieties of Cynodon dactylon were investigated,and the number,length,and width of long and short cells and stomata were measured.The results showed that the anticlinal wall of epidermal cells looked like waves and the stoma was distributed in the upper and lower epidermis.However,the various indicators of the leaf epidermis of different species of Cd were significantly different.The length and width of long cells and the length of short cells of Cd Mohawk,Cd Suncity,and wild type Cd were relatively large,which may improve their ability to adapt to the pastoral soil and make them suitable for the rainy environment of the Jianghan Plain.On the contrary,the results of all indicators of Cd Xinnong 1,Cd hulled,and Cd unhulled ranked at the bottom,which was not suitable for pastoral soil habitats,while the wild type Cd could adapt to both the pastoral soil and the vegetation concrete habitat.Moreover,the long cells and short cells of Cd Kashi were tightly arranged,and the stoma in Cd Pyramid and Cd hulled were more dense,which may improve their ability to adapt to an arid environment.展开更多
Ultrastructual characteristics of Sertoli cells of Salmonidae from Ohrid Lake during the spermatogenetic cycle have been analysed. Sertoli cells being an integral part of the seminiferous lobules underwent considerabl...Ultrastructual characteristics of Sertoli cells of Salmonidae from Ohrid Lake during the spermatogenetic cycle have been analysed. Sertoli cells being an integral part of the seminiferous lobules underwent considerable changes, which influenced their cytomorphological features. The degenerative changes of Sertoli cells were manifested by an extreme vacuolisation, mitochondria in degeneration with widened crysts and thickened matrix, desorganised ER, autophagosomes, ＂myeline-like＂ structures and lysed cytoplasmic regions. The above mentioned changes were followed by karyopycnisis, comlete degeneration and delamination of cells from the wall of the seminiferous lobules, lysis and detritus formations （Sertoli necrotic material） in the lumen of the lobules. The aim of this paper is special research of the ultrastructural characteristics, i.e. the changes on a level with testes which happen in the postspawning period in the two species of Teleostei of Ohrid Lake, Ohrid trout （Salmo letnica Kar.） and Ohrid belvica （Acantholingua ochridana Steind.）. The postspawning period is emphasized in Teleostei in this relatively short period, when one reproductive cycle finishes and the following has to start, on a level of testicular parenhyma very important histological changes are going on which give special histological identification, i. e. in the postspawning period there is a complete reorganization of the testes.展开更多
Extracting the cell objects of red tide algae is the most important step in the construction of an automatic microscopic image recognition system for harmful algal blooms.This paper describes a set of composite method...Extracting the cell objects of red tide algae is the most important step in the construction of an automatic microscopic image recognition system for harmful algal blooms.This paper describes a set of composite methods for the automatic segmentation of cells of red tide algae from microscopic images.Depending on the existence of setae,we classify the common marine red tide algae into non-setae algae species and Chaetoceros,and design segmentation strategies for these two categories according to their morphological characteristics.In view of the varied forms and fuzzy edges of non-setae algae,we propose a new multi-scale detection algorithm for algal cell regions based on border-correlation,and further combine this with morphological operations and an improved GrabCut algorithm to segment single-cell and multicell objects.In this process,similarity detection is introduced to eliminate the pseudo cellular regions.For Chaetoceros,owing to the weak grayscale information of their setae and the low contrast between the setae and background,we propose a cell extraction method based on a gray surface orientation angle model.This method constructs a gray surface vector model,and executes the gray mapping of the orientation angles.The obtained gray values are then reconstructed and linearly stretched.Finally,appropriate morphological processing is conducted to preserve the orientation information and tiny features of the setae.Experimental results demonstrate that the proposed methods can effectively remove noise and accurately extract both categories of algae cell objects possessing a complete shape,regular contour,and clear edge.Compared with other advanced segmentation techniques,our methods are more robust when considering images with different appearances and achieve more satisfactory segmentation effects.展开更多
Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell ...Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell morphology before and after Cr(Ⅵ) reduction was observed with a scanning electron microscope(SEM),and the reduction product is found to adhere to terminals of CH-1 cells.Energy-dispersive X-ray(EDX) and electron paramagnetic resonance(EPR) analyses reveal that the main component of the reduction product is Cr(Ⅲ).Furthermore,small and large-scale demonstration projects reveal that Achromobacter sp.can be used to detoxify chromium-containing slag and to selectively recover chromium by using this novel technique.Chromium recovery rate increases with decreasing particle sizes of chromium-containing slag and slagheap height.Chromium recovery rates in 10 t/batch and 20 t/batch of on-site demonstration projects for chromium-containing slag detoxification are more than 90%.展开更多
Bacteriophages or more commonly ＂phages＂ are bacterial viruses. They are ubiquitous and good indicators of bacterial contaminations since their prevalence is high in those environments where their hosts are abundant...Bacteriophages or more commonly ＂phages＂ are bacterial viruses. They are ubiquitous and good indicators of bacterial contaminations since their prevalence is high in those environments where their hosts are abundant. Phage classification is based on morphology and for this reason, even though it is considered an old technique, TEM （Transmission Electron Microscopy） still plays a key role in their characterization. In the present work, the authors focused on TEM analysis of phage ФApr-1 isolated against Lactococcuslactis （L. lactis）, implicated in industrial fermentations and of phage ФIZSAM-1, active against Listeria monocytogenes （L. monocytogenes）, isolated from the environment. For observation with TEM （EM 900T-Zeiss）, phages were harvested in liquid media and were negative stained with fosfotungstic acid 2‰. An accurate viral ultrastructure analysis by using TEM is fundamental not only in the first approach of characterization of newly isolated phages but also for providing useful information to go further to the selection process as potential bio-decontaminants.展开更多
Superabsorbent polymers(SAPs) as soil moisture conditioners have been increasingly used in agriculture, but conflicting results were reported regarding the effects of SAPs on crop growth. In this study, both laborator...Superabsorbent polymers(SAPs) as soil moisture conditioners have been increasingly used in agriculture, but conflicting results were reported regarding the effects of SAPs on crop growth. In this study, both laboratory cultivation and analysis were conducted to investigate the effects of different SAPs on the growth and physiology of crops under water-saving agricultural practices. Maize(Zea mays L.) seedlings were cultivated using distilled water or three different SAP hydrogels, sodium polyacrylate(SP), potassium polyacrylate(PP), and sodium polyacrylate embedded with phosphate rock powder(SPP), as growth media. Growth characteristics of the model plant and damage were assessed using scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results showed that both the SP and PP treatments had pronounced negative effect on the hydrogels of growth of maize seedlings. The SPP treatment appeared to facilitate the stem-leaf growth and had no obvious adverse effect on root growth. All the three hydrogel treatments caused varying degrees of damage to the organizational structure and cellular morphology of the roots, with the SP and PP treatments causing the most severe damage; the membrane system of root cells was damaged by both SP and PP treatments. An excessive accumulation of sodium and reduction of calcium occurred in the roots may be responsible for the observed damage to the cell membrane system, which, in turn, may have promoted the wilting of the cells.展开更多
Cell mechanics plays an important role in cellular physiological activities. Recent studies have shown that cellular mechanical properties are novel biomarkers for indicating the cell states. In this article, temperat...Cell mechanics plays an important role in cellular physiological activities. Recent studies have shown that cellular mechanical properties are novel biomarkers for indicating the cell states. In this article, temperature-controllable atomic force microscopy(AFM) was applied to quantitatively investigate the effects of temperature and cellular interactions on the mechanics and morphology of human cancer cells. First, AFM indenting experiments were performed on six types of human cells to investigate the changes of cellular Young's modulus at different temperatures and the results showed that the mechanical responses to the changes of temperature were variable for different types of cancer cells. Second, AFM imaging experiments were performed to observe the morphological changes in living cells at different temperatures and the results showed the significant changes of cell morphology caused by the alterations of temperature. Finally, by co-culturing human cancer cells with human immune cells, the mechanical and morphological changes in cancer cells were investigated. The results showed that the co-culture of cancer cells and immune cells could cause the distinct mechanical changes in cancer cells, but no significant morphological differences were observed. The experimental results improved our understanding of the effects of temperature and cellular interactions on the mechanics and morphology of cancer cells.展开更多
文摘To identify suitable grass species for growth in the Jianghan Plain,the micromorphologies of the upper and lower epidermis of the leaves of 14 bermudagrass varieties of Cynodon dactylon were investigated,and the number,length,and width of long and short cells and stomata were measured.The results showed that the anticlinal wall of epidermal cells looked like waves and the stoma was distributed in the upper and lower epidermis.However,the various indicators of the leaf epidermis of different species of Cd were significantly different.The length and width of long cells and the length of short cells of Cd Mohawk,Cd Suncity,and wild type Cd were relatively large,which may improve their ability to adapt to the pastoral soil and make them suitable for the rainy environment of the Jianghan Plain.On the contrary,the results of all indicators of Cd Xinnong 1,Cd hulled,and Cd unhulled ranked at the bottom,which was not suitable for pastoral soil habitats,while the wild type Cd could adapt to both the pastoral soil and the vegetation concrete habitat.Moreover,the long cells and short cells of Cd Kashi were tightly arranged,and the stoma in Cd Pyramid and Cd hulled were more dense,which may improve their ability to adapt to an arid environment.
文摘Ultrastructual characteristics of Sertoli cells of Salmonidae from Ohrid Lake during the spermatogenetic cycle have been analysed. Sertoli cells being an integral part of the seminiferous lobules underwent considerable changes, which influenced their cytomorphological features. The degenerative changes of Sertoli cells were manifested by an extreme vacuolisation, mitochondria in degeneration with widened crysts and thickened matrix, desorganised ER, autophagosomes, ＂myeline-like＂ structures and lysed cytoplasmic regions. The above mentioned changes were followed by karyopycnisis, comlete degeneration and delamination of cells from the wall of the seminiferous lobules, lysis and detritus formations （Sertoli necrotic material） in the lumen of the lobules. The aim of this paper is special research of the ultrastructural characteristics, i.e. the changes on a level with testes which happen in the postspawning period in the two species of Teleostei of Ohrid Lake, Ohrid trout （Salmo letnica Kar.） and Ohrid belvica （Acantholingua ochridana Steind.）. The postspawning period is emphasized in Teleostei in this relatively short period, when one reproductive cycle finishes and the following has to start, on a level of testicular parenhyma very important histological changes are going on which give special histological identification, i. e. in the postspawning period there is a complete reorganization of the testes.
基金Supported by the National Natural Science Foundation of China(Nos.61301240,61271406)
文摘Extracting the cell objects of red tide algae is the most important step in the construction of an automatic microscopic image recognition system for harmful algal blooms.This paper describes a set of composite methods for the automatic segmentation of cells of red tide algae from microscopic images.Depending on the existence of setae,we classify the common marine red tide algae into non-setae algae species and Chaetoceros,and design segmentation strategies for these two categories according to their morphological characteristics.In view of the varied forms and fuzzy edges of non-setae algae,we propose a new multi-scale detection algorithm for algal cell regions based on border-correlation,and further combine this with morphological operations and an improved GrabCut algorithm to segment single-cell and multicell objects.In this process,similarity detection is introduced to eliminate the pseudo cellular regions.For Chaetoceros,owing to the weak grayscale information of their setae and the low contrast between the setae and background,we propose a cell extraction method based on a gray surface orientation angle model.This method constructs a gray surface vector model,and executes the gray mapping of the orientation angles.The obtained gray values are then reconstructed and linearly stretched.Finally,appropriate morphological processing is conducted to preserve the orientation information and tiny features of the setae.Experimental results demonstrate that the proposed methods can effectively remove noise and accurately extract both categories of algae cell objects possessing a complete shape,regular contour,and clear edge.Compared with other advanced segmentation techniques,our methods are more robust when considering images with different appearances and achieve more satisfactory segmentation effects.
文摘Based on the principle of bacterial leaching and bacterial metallurgy,a novel technology for the detoxification of chromium-containing slag by Achromobacter sp.CH-1 and chromium recovery was proposed.Strain CH-1 cell morphology before and after Cr(Ⅵ) reduction was observed with a scanning electron microscope(SEM),and the reduction product is found to adhere to terminals of CH-1 cells.Energy-dispersive X-ray(EDX) and electron paramagnetic resonance(EPR) analyses reveal that the main component of the reduction product is Cr(Ⅲ).Furthermore,small and large-scale demonstration projects reveal that Achromobacter sp.can be used to detoxify chromium-containing slag and to selectively recover chromium by using this novel technique.Chromium recovery rate increases with decreasing particle sizes of chromium-containing slag and slagheap height.Chromium recovery rates in 10 t/batch and 20 t/batch of on-site demonstration projects for chromium-containing slag detoxification are more than 90%.
文摘Bacteriophages or more commonly ＂phages＂ are bacterial viruses. They are ubiquitous and good indicators of bacterial contaminations since their prevalence is high in those environments where their hosts are abundant. Phage classification is based on morphology and for this reason, even though it is considered an old technique, TEM （Transmission Electron Microscopy） still plays a key role in their characterization. In the present work, the authors focused on TEM analysis of phage ФApr-1 isolated against Lactococcuslactis （L. lactis）, implicated in industrial fermentations and of phage ФIZSAM-1, active against Listeria monocytogenes （L. monocytogenes）, isolated from the environment. For observation with TEM （EM 900T-Zeiss）, phages were harvested in liquid media and were negative stained with fosfotungstic acid 2‰. An accurate viral ultrastructure analysis by using TEM is fundamental not only in the first approach of characterization of newly isolated phages but also for providing useful information to go further to the selection process as potential bio-decontaminants.
基金supported by the National Natural Science Foundation of China (Nos. 30600347 and 41071162)the Science and Technology Program of Guangzhou City, China (Nos. 201508030039 and 201604020074)
文摘Superabsorbent polymers(SAPs) as soil moisture conditioners have been increasingly used in agriculture, but conflicting results were reported regarding the effects of SAPs on crop growth. In this study, both laboratory cultivation and analysis were conducted to investigate the effects of different SAPs on the growth and physiology of crops under water-saving agricultural practices. Maize(Zea mays L.) seedlings were cultivated using distilled water or three different SAP hydrogels, sodium polyacrylate(SP), potassium polyacrylate(PP), and sodium polyacrylate embedded with phosphate rock powder(SPP), as growth media. Growth characteristics of the model plant and damage were assessed using scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results showed that both the SP and PP treatments had pronounced negative effect on the hydrogels of growth of maize seedlings. The SPP treatment appeared to facilitate the stem-leaf growth and had no obvious adverse effect on root growth. All the three hydrogel treatments caused varying degrees of damage to the organizational structure and cellular morphology of the roots, with the SP and PP treatments causing the most severe damage; the membrane system of root cells was damaged by both SP and PP treatments. An excessive accumulation of sodium and reduction of calcium occurred in the roots may be responsible for the observed damage to the cell membrane system, which, in turn, may have promoted the wilting of the cells.
基金supported by the National Natural Science Foundation of China(61175103,61375107,61327014,61433017)the Research Fund of the State Key Laboratory of Robotics(2014-Z07)CAS FEA International Partnership Program for Creative Research Teams
文摘Cell mechanics plays an important role in cellular physiological activities. Recent studies have shown that cellular mechanical properties are novel biomarkers for indicating the cell states. In this article, temperature-controllable atomic force microscopy(AFM) was applied to quantitatively investigate the effects of temperature and cellular interactions on the mechanics and morphology of human cancer cells. First, AFM indenting experiments were performed on six types of human cells to investigate the changes of cellular Young's modulus at different temperatures and the results showed that the mechanical responses to the changes of temperature were variable for different types of cancer cells. Second, AFM imaging experiments were performed to observe the morphological changes in living cells at different temperatures and the results showed the significant changes of cell morphology caused by the alterations of temperature. Finally, by co-culturing human cancer cells with human immune cells, the mechanical and morphological changes in cancer cells were investigated. The results showed that the co-culture of cancer cells and immune cells could cause the distinct mechanical changes in cancer cells, but no significant morphological differences were observed. The experimental results improved our understanding of the effects of temperature and cellular interactions on the mechanics and morphology of cancer cells.
