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Kim B Shin JH Han K Seo HW Oh Y Kang I Park C Lee BH Jang JS Kim SH Chae C 《Veterinary research communications》2011,35(7):469-475
The expression of myeloperoxidase (MPO) was examined in the swine influenza virus (SIV)-infected neutrophils in the lungs of pigs experimentally infected with swine influenza virus (SIV) subtype H1N2 by immunohistochemistry. Five pigs each from the infected and non-infected group were euthanized 1, 3, 5, 7, and 10?days post-inoculation (dpi). Immunohistochemical reactivity was mainly seen in neutrophils. The score for pulmonary histopathological lesions correlated with the score for MPO immunohistochemical reactivity (r ( s )?=?0.962, P?0.01). In addition, the score for in situ hybridization of SIV nucleic acid correlated with the score for MPO immunohistochemical reactivity (r ( s )?=?0.976, P?0.01). These results suggest neutrophils are one of the primary effector cells in the early phase of SIV infection in pigs. 相似文献
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To assess the effects of negative and positive behaviors on milk yields, this study examined the attitudes and behaviors of stockpersons toward their cows and milk yields at a farm where 15 workers milked 67 cows as rotating shift work. At a holding area when moving cows to the parlor, stockperson behaviors were observed at 34 milkings. Behaviors were classified as negative (NEG) or positive (POS): NEG were attempts to move cows using touching (NT), vocalization (NV), and gestures (NG); POS were communications without attempting to move cows, consisting of touch (PT) or vocalization (PV). Numbers of NV and NEG were negatively correlated with milk yields of first parity (p < .05). Average milk yields of first parity and all cows were higher when PT were observed (p < .001, p < .0001) and POS were observed (p < .001 and p < .0001). Numbers of PT were positively correlated with milk yields of first parity (p < .05). Average milk yields of second parity were higher when PV was observed (p < .01). Positive behaviors, especially touching, are related to higher herd milk yields. Negative behaviors such as negative vocalizations are related to lower yields of younger cows. 相似文献
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Estimating the onset of cambial activity in Scots pine in northern Finland by means of the heat-sum approach 总被引:1,自引:0,他引:1
We estimated the date of onset (Date(est)) of cambial activity by the pinning method in Scots pine (Pinus sylvestris L.) trees at Vanttauskoski (Site 1) and Laanila (Site 2) near the latitudinal limit of Scots pine in northern Finland. In each year and at each site, observations were made on a different set of five trees. The estimated dates of onset of cambial activity were compared with the corresponding heat sums, calculated in degree-days according to two models. Within years, Date(est) varied among trees by up to 15 days at Site 1 and up to 13 days at Site 2. Among years, mean Date(est) varied by 15.3 days at Site 1 and 12.0 days at Site 2. The overall mean Date(est) differed between sites by 6 days (June 5 at Site 1 and June 11 at Site 2). Among all trees in all years, the mean number of degree days (d.d.) calculated from mean daily temperature above a threshold of 5 degrees C before Date(est) ranged from 68.7 to 135 d.d. at Site 1 and from 37.4 to 154.7 d.d. at Site 2. Among years, the mean heat sum before Date(est )ranged from 94 to 112.5 d.d. at Site 1 and from 61.4 to 136 d.d. at Site 2. Variation among years in heat sum before Date(est) at Site 2 was highly significant, indicating that one or more factors other than, or in addition to, heat sum determines the onset of cambial activity in Scots pine. Similar results were obtained when heat sum was computed from the area between the sine wave generated by daily maximum and minimum temperature and the threshold temperature. 相似文献
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A high molecular weight polyhydroxyamide (PHA) solution in N, N-dimethyl acetamide (DMAc) was prepared from 3,3′-dihydroxybenzidine
and isophthalic chloride (IPC), which was used for spinning PHA fiber. Before spinning, the diffusion property of DMAc into
various coagulants was examined. The fiber was well formed in coagulants such as water/ethanol with a composition of 5/5,
ethanol, and ethanol/isopropanol with a composition of 7/3 and 5/5. However, the PHA fiber spun in the water/ethanol mixture
contained voids. After the fiber spun in ethanol was annealed at over 350°C, the ultimate stress and initial modulus of the
fiber increased from 75.5 MPa and 3.22 GPa to 369 MPa and 29.5 GPa, respectively. These properties of the PHA fiber spun by
the dry spinning method were also enhanced, attaining 154 MPa and 5.56 Gpa, respectively. 相似文献
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Flow analysis of profile extrusion is essential for design and production of a profile extrusion die. Velocity, pressure,
and temperature distribution in an extrusion die are predicted and compared with the experimental results. A two dimensional
numerical method is proposed for three dimensional analysis of the flow field within the profile extrusion die by applying
a modified cross-sectional numerical method. Since the cross-sectional shape of the die is varied gradually, it is assumed
that the pressure is constant within a cross-sectional plane that is perpendicular to the flow direction. With this assumption,
the velocity component in the cross-sectional direction is neglected. The exact cross-sectional shape at any position is calculated
based on the geometry of standard cross-sections. The momentum and energy equations are solved with proper boundary conditions
at a cross-section and then the same calculation is carried out for the next cross-section using the current calculated values.
An L-shaped profile extrusion die is produced and employed for experimental investigation using a commercially available polypropylene.
Numerical prediction for the varying cross-sectional shape provides better results than the previous studies and is in good
agreement with the experimental results. 相似文献
60.
Involvement of a vascular hypersensitive response in quantitative resistance to Ralstonia solanacearum on tomato rootstock cultivar LS‐89 下载免费PDF全文
K. Nakaho S. Seo K. Ookawa Y. Inoue S. Ando Y. Kanayama S. Miyashita H. Takahashi 《Plant pathology》2017,66(1):150-158
Ralstonia solanacearum causes bacterial wilt disease in Solanaceae spp. Expression of the Phytophthora inhibitor protease 1 (PIP1) gene, which encodes a papain‐like extracellular cysteine protease, is induced in R. solanacearum‐inoculated stem tissues of quantitatively resistant tomato cultivar LS‐89, but not in susceptible cultivar Ponderosa. Phytophthora inhibitor protease 1 is closely related to Rcr3, which is required for the Cf‐2‐mediated hypersensitive response (HR) to the leaf mould fungus Cladosporium fulvum and manifestation of HR cell death. However, up‐regulation of PIP1 in R. solanacearum‐inoculated LS‐89 stems was not accompanied by visible HR cell death. Nevertheless, upon electron microscopic examination of inoculated stem tissues of resistant cultivar LS‐89, several aggregated materials associated with HR cell death were observed in xylem parenchyma and pith cells surrounding xylem vessels. In addition, the accumulation of electron‐dense substances was observed within the xylem vessel lumen of inoculated stems. Moreover, when the leaves of LS‐89 or Ponderosa were infiltrated with 106 cells mL?1 R. solanacearum, cell death appeared in LS‐89 at 18 and 24 h after infiltration. The proliferation of bacteria in the infiltrated leaf tissues of LS‐89 was suppressed to approximately 10–30% of that in Ponderosa, and expression of the defence‐related gene PR‐2 and HR marker gene hsr203J was induced in the infiltrated tissues. These results indicated that the response of LS‐89 is a true HR, and induction of vascular HR in xylem parenchyma and pith cells surrounding xylem vessels seems to be associated with quantitative resistance of LS‐89 to R. solanacearum. 相似文献