Toxoplasmosis is an important cause of reproductive failure in man and farm animals resulting in significant socio-economic losses worldwide. The aim of this study was to avail large scale data-regarding the sero-prev...Toxoplasmosis is an important cause of reproductive failure in man and farm animals resulting in significant socio-economic losses worldwide. The aim of this study was to avail large scale data-regarding the sero-prevalence of T. gondii infection in dairy animals from the Khartoum State, Sudan using the commercially available Latex Agglutination Diagnostic kits. The study revealed that the overall seroprevalence of T. gondii infection at herd level of dairy animals in the State was 92.7%. The within herd seroprevalence was ranging from 8% up to 100% with mean of 51.3% in different herds of different dairy animals species in the State. Only 6 herds, 3 herds, 3 herds and 1 herd of cattle, camel sheep and goat respectively were found to be clean from anti-T, gondii antibody in the present study. Interestingly, most of the clean herds (12 herds) are located in the Khartoum district. The differences between the three districts, the seven localities and the four animal species were statistically highly significant (P 〈 0.01). The overall sero-prevalence of T. gondii infection in dairy animals--at individual level--was 45.3%. Sheep scored the highest seroprevalence rate (75.0%) followed by goats (64.0%), camels (54.1%) and cattle (40.9%) with high statistically significant differences (P 〈 0.01). The highest level of antibody titration was reported in sheep and goats. This is the first area-wide and large scale report on seroprevalence of T. gondii infection in dairy animals from the Sudan. It was concluded that dairy animals in the Sudan are widely exposed to T. gondii and people in the Sudan should be aware of the possibility of hyper-prevalence of human toxoplasmosis through these food animals. Research on clinical toxoplasmosis in dairy animals and human in the Sudan is recommended to evaluate the role T. gondii infection in economical losses in dairy farm industry and for building strategy of sustainable toxoplasmosis control.展开更多
A snake algorithm has been known that it has a strong point in extracting the exact contour of an object. But it is apt to be influenced by scattered edges around the control points. Since the shape of a moving object...A snake algorithm has been known that it has a strong point in extracting the exact contour of an object. But it is apt to be influenced by scattered edges around the control points. Since the shape of a moving object in 2D image changes a lot due to its rotation and translation in the 3D space, the conventional algorithm that takes into account slowly moving objects cannot provide an appropriate solution. To utilize the advantages of the snake algorithm while minimizing the drawbacks, this paper proposes the area variation based color snake algorithm for moving object tracking. The proposed algorithm includes a new energy term which is used for preserving the shape of an object between two consecutive images. The proposed one can also segment precisely interesting objects on complex image since it is based on color information. Experiment results show that the proposed algorithm is very effective in various environments.展开更多
A pot experiment was conducted to investigate the action mechanisms phorus (P) uptake of Capsicum annuum L. in a sterilized fossil Oxisol of arbuscular mycorrhizal (AM) fungi in phos- Three P levels of 0, 10 and 2...A pot experiment was conducted to investigate the action mechanisms phorus (P) uptake of Capsicum annuum L. in a sterilized fossil Oxisol of arbuscular mycorrhizal (AM) fungi in phos- Three P levels of 0, 10 and 200 mg kg-1 soil (P0, P10 and P200, respectively) without and with AM fungal inoculation were applied as Ca(H2PO4)2-H20. Shoot dry matter yields and shoot P uptake increased significantly (P 〉 0.05) by the inoculation of AM fungi at P0 and P10. Root length and P concentration in soil solution increased with the inoculation of AM fungi but the root:shoot ratio decreased or remained constant. Around 50% roots of inoculated plants were infected by AM and the external hyphae amounted to 20 m g^-1 soil at P10 and P200. The hyphae surface area of the infected root cylinder amounted to 11 and 2 cm^2 cm^-2 root at P0 and P10, respectively. The increased P uptake of inoculated plants was mainly because of an up to 5 times higher P influx of the infected root. Model calculations showed that the root alone could not have achieved the measured P influx in both infected and non-infected roots. But the P influx for hyphae calculated by the model was even much higher than the measured one. The P uptake capacity of hyphae introduced in the model was too high. Model calculations further showed that the depletion zone around roots or hyphae was very narrow. In the case of the root only 7% of the soil volume would contribute P to the plant, while in the case of hyphae it would be 100%. The results together with the model calculations showed that the increased P uptake of AM inoculated plants could be explained partly by the increased P concentration in the soil solution and by the increased P absorbing surface area coming from the external hyphae.展开更多
In this paper, the phase behavior and interracial properties of symmetric ternary polymeric blends A/B/AB are studied by dissipative particle dynamics (DPD) simulations. By using the structure factor and nematic ord...In this paper, the phase behavior and interracial properties of symmetric ternary polymeric blends A/B/AB are studied by dissipative particle dynamics (DPD) simulations. By using the structure factor and nematic order parameter, we carefully characterized the diversified phases and phase transitions, and established the phase diagram of such symmetric ternary blends. It can be generally divided into four regions: disordered phase (DIS) region at high temperature, ordered lameUar phase (LAM) region, bicontinuous microemulsion (BμE) channel and phase-separated phase (2P) region at low temperature with the increase of the total volume fractions of homopolymers φn, which shows good accordance with that in previous experimental and theoretical reports. Furthermore, we calculated the elastic constants of 2P and LAM phase, and discussed the transition mechanisms from 2P and LAM to BμE phase, respectively. The results show a direct relevance between the phase transitions and the change of interfacial properties. Finally, we also demonstrate that the B,uE channel becomes narrower in lower temperature caused by the temperature dependence of interfacial properties of ternary blends.展开更多
文摘Toxoplasmosis is an important cause of reproductive failure in man and farm animals resulting in significant socio-economic losses worldwide. The aim of this study was to avail large scale data-regarding the sero-prevalence of T. gondii infection in dairy animals from the Khartoum State, Sudan using the commercially available Latex Agglutination Diagnostic kits. The study revealed that the overall seroprevalence of T. gondii infection at herd level of dairy animals in the State was 92.7%. The within herd seroprevalence was ranging from 8% up to 100% with mean of 51.3% in different herds of different dairy animals species in the State. Only 6 herds, 3 herds, 3 herds and 1 herd of cattle, camel sheep and goat respectively were found to be clean from anti-T, gondii antibody in the present study. Interestingly, most of the clean herds (12 herds) are located in the Khartoum district. The differences between the three districts, the seven localities and the four animal species were statistically highly significant (P 〈 0.01). The overall sero-prevalence of T. gondii infection in dairy animals--at individual level--was 45.3%. Sheep scored the highest seroprevalence rate (75.0%) followed by goats (64.0%), camels (54.1%) and cattle (40.9%) with high statistically significant differences (P 〈 0.01). The highest level of antibody titration was reported in sheep and goats. This is the first area-wide and large scale report on seroprevalence of T. gondii infection in dairy animals from the Sudan. It was concluded that dairy animals in the Sudan are widely exposed to T. gondii and people in the Sudan should be aware of the possibility of hyper-prevalence of human toxoplasmosis through these food animals. Research on clinical toxoplasmosis in dairy animals and human in the Sudan is recommended to evaluate the role T. gondii infection in economical losses in dairy farm industry and for building strategy of sustainable toxoplasmosis control.
文摘A snake algorithm has been known that it has a strong point in extracting the exact contour of an object. But it is apt to be influenced by scattered edges around the control points. Since the shape of a moving object in 2D image changes a lot due to its rotation and translation in the 3D space, the conventional algorithm that takes into account slowly moving objects cannot provide an appropriate solution. To utilize the advantages of the snake algorithm while minimizing the drawbacks, this paper proposes the area variation based color snake algorithm for moving object tracking. The proposed algorithm includes a new energy term which is used for preserving the shape of an object between two consecutive images. The proposed one can also segment precisely interesting objects on complex image since it is based on color information. Experiment results show that the proposed algorithm is very effective in various environments.
基金Supported by the Higher Education Commission of Pakistan
文摘A pot experiment was conducted to investigate the action mechanisms phorus (P) uptake of Capsicum annuum L. in a sterilized fossil Oxisol of arbuscular mycorrhizal (AM) fungi in phos- Three P levels of 0, 10 and 200 mg kg-1 soil (P0, P10 and P200, respectively) without and with AM fungal inoculation were applied as Ca(H2PO4)2-H20. Shoot dry matter yields and shoot P uptake increased significantly (P 〉 0.05) by the inoculation of AM fungi at P0 and P10. Root length and P concentration in soil solution increased with the inoculation of AM fungi but the root:shoot ratio decreased or remained constant. Around 50% roots of inoculated plants were infected by AM and the external hyphae amounted to 20 m g^-1 soil at P10 and P200. The hyphae surface area of the infected root cylinder amounted to 11 and 2 cm^2 cm^-2 root at P0 and P10, respectively. The increased P uptake of inoculated plants was mainly because of an up to 5 times higher P influx of the infected root. Model calculations showed that the root alone could not have achieved the measured P influx in both infected and non-infected roots. But the P influx for hyphae calculated by the model was even much higher than the measured one. The P uptake capacity of hyphae introduced in the model was too high. Model calculations further showed that the depletion zone around roots or hyphae was very narrow. In the case of the root only 7% of the soil volume would contribute P to the plant, while in the case of hyphae it would be 100%. The results together with the model calculations showed that the increased P uptake of AM inoculated plants could be explained partly by the increased P concentration in the soil solution and by the increased P absorbing surface area coming from the external hyphae.
基金supported by the National Natural Science Foundation of China(21174154,20874110,50930002)
文摘In this paper, the phase behavior and interracial properties of symmetric ternary polymeric blends A/B/AB are studied by dissipative particle dynamics (DPD) simulations. By using the structure factor and nematic order parameter, we carefully characterized the diversified phases and phase transitions, and established the phase diagram of such symmetric ternary blends. It can be generally divided into four regions: disordered phase (DIS) region at high temperature, ordered lameUar phase (LAM) region, bicontinuous microemulsion (BμE) channel and phase-separated phase (2P) region at low temperature with the increase of the total volume fractions of homopolymers φn, which shows good accordance with that in previous experimental and theoretical reports. Furthermore, we calculated the elastic constants of 2P and LAM phase, and discussed the transition mechanisms from 2P and LAM to BμE phase, respectively. The results show a direct relevance between the phase transitions and the change of interfacial properties. Finally, we also demonstrate that the B,uE channel becomes narrower in lower temperature caused by the temperature dependence of interfacial properties of ternary blends.