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51.
    
The high-temperature treatment of paprika oleoresins (Capsicum annuum L.) modified the carotenoid profile, yielding several degradation products, which were analyzed by HPLC-APCI-MS. From the initial MS data, compounds were grouped in two sets. Set 1 grouped compounds with m/z 495, and set 2 included compounds with m/z 479, in both cases for the protonated molecular mass. Two compounds of the first set were tentatively identified as 9,10,11,12,13,14,19,20-octanor-capsorubin (compound II) and 9,10,11,12,13,14,19,20-octanor-5,6-epoxide-capsanthin (compound IV), after isolation by semipreparative HPLC and analysis by EI-MS. Compounds VII, VIII, and IX from set 2 were assigned as 9,10,11,12,13,14,19,20-octanor-capsanthin and isomers, respectively. As these compounds were the major products formed in the thermal process, it was possible to apply derivatization techniques (hydrogenation and silylation) to analyze them by EI-MS, before and after chemical derivatization. Taking into account structures of the degradation products, the cyclization of polyolefins could be considered as the general reaction pathway in thermally induced reactions, yielding in the present study xylene as byproduct and the corresponding nor-carotenoids.  相似文献   
52.
    
During 2001, a mild infectious laryngotracheitis virus (ILTV) infection occurred in broiler flocks in the southeastern United States. Clinical signs included mild tracheitis, swollen sinuses, and conjunctivitis, with no increased mortality and minimal serologic response. Infrequent intranuclear inclusion bodies with or without syncytial cell formation were observed in eyelid, trachea, and larynx and in the chorioallantoic membrane of infected embryos. Immunohistochemistry and a nested infectious laryngotracheitis polymerase chain reaction (ILT PCR) were utilized to confirm the presence of ILTV nucleic acid in fixed tissues. In addition, 2-wk-old specific-pathogen-free (SPF) birds inoculated with field material exhibited the mild signs observed in broilers in the field. Tracheal swabs and tissues taken from these SPF birds were also positive by nested ILT PCR. Restriction fragment length polymorphism analysis of ILT PCR products indicated that ILT virus associated with mild respiratory disease in the southeast is related to the chicken embryo origin vaccine type strains.  相似文献   
53.
In recent years, multiple cases of aggressive behavior of Common ravens (Corvus corax) have been reported by farmers in Catalonia (NE Spain), including attacking of newborn animals and consumption of dead foetuses. In the present study, seroprevalence of Toxoplasma gondii and Neospora caninum was determined from 113 legally trapped and released Common ravens. T. gondii antibodies were found in 91 (80.5%; CI 95%:72-87) of 113 sera tested by the modified agglutination test. Antibodies to N. caninum were found in 24 (35.8%; IC 95%: 24.5-48.5) of 67 Common ravens tested by an indirect fluorescence antibody test with titers ranging from 1:50 (n=18) to ≥1:100 (n=6). To the author's knowledge, this is the first report of the presence of T. gondii and N. caninum antibodies in C. corax. The seroprevalence detected is one of the highest reported worldwide in wild birds, suggesting an important role for this species in the epidemiology of both parasites.  相似文献   
54.
    
Osmotic dehydration was assessed as an operation for supplementing a solid foodstuff (a gel was used as the model food) with grape phenolics from a concentrated red grape must to increase its antioxidant properties. The model food was processed for up to 24 h, and the osmotic pressure was adjusted by diluting the concentrated red grape must. In all conditions tested, low molecular weight phenolics (相似文献   
55.
Ten dogs were presented with fractures of the proximal tibial epiphysis and tuberosity. All dogs had a cranioproximal-caudodistal angulation of the tibial plateau. Six dogs had marked caudal displacement of the proximal tibial epiphysis, five of which had also sustained fractures of the proximal fibula. The estimated mean angle of inclination of the tibial plateau of affected limbs was 45.8 +/- 9.6 degrees, which was significantly greater (P<0.0005) than the estimated mean angle of the normal contralateral limb 26.2 +/- 6.6 degrees. The mean angle of inclination of the tibial plateau of dogs with fibular fractures (n=5) was not significantly different from dogs without fibular fractures (n=5) (P>0.25). Five dogs were treated conservatively and five were treated by three different methods of surgical repair. Surgically treated dogs had significantly greater preoperative tibial plateau angles (P<0.05). All dogs regained full limb usage, regardless of the method of treatment chosen.  相似文献   
56.
Two experiments were conducted to determine whether exposure to a photoperiod of artificial long days in autumn increased milk yield in subtropical goats milked once (Exp. I) or twice daily (Exp. II). In Exp. I, starting at d 10 of lactation, 1 group of does was kept under naturally decreasing photoperiod (DD1X; n = 8), whereas the other group was submitted to an artificial photoperiod of long days (LD1X; n = 8; 16 h light:8 h darkness). The kids were weaned 28 d after parturition, and dams were manually milked once daily. Milk yield and milk components (fat, protein, and lactose) were assessed up to 140 d of lactation. From d 0 to 28 of lactation (suckling phase), mean daily milk yield did not differ between DD1X and LD1X goats (2.3 ± 0.2 kg vs. 2.4 ± 0.2 kg; P = 0.717). However, between d 29 and 84 (early milking phase), mean daily milk yield was greater in LD1X does than in DD1X does (2.6 ± 0.1 kg vs. 2.1 ± 0.1 kg; P = 0.001). Finally, between d 85 and 140 (late milking phase), mean daily milk yield was greater in LD1X goats than in DD1X goats (P ≤ 0.05) only during the first 2 wk. In Exp. II, one group of goats was exposed to a photoperiod of naturally decreasing days (DD2X; n = 8) and another group was submitted to an artificial photoperiod of long days (LD2X; n = 7). In both groups, kids were weaned on d 28 of lactation and the dams were manually milked twice daily. During the nursing phase, mean daily milk yield did not differ between the DD2X and LD2X groups (2.5 ± 0.3 kg vs. 2.6 ± 0.2 kg; P = 0.767). In the early milking phase, mean daily milk yield was greater in LD2X than in DD2X goats (3.3 ± 0.2 kg vs. 2.8 ± 0.2 kg; P = 0.022), whereas during the late milking phase, milk yield did not differ between the 2 groups (P = 0.946). In both experiments, milk composition was not significantly influenced by exposure to long-day photoperiod. We conclude that, in subtropical female goats that start lactation in late autumn, exposure to an artificial long-day photoperiod stimulates milk yield, even if goats are milked once daily. In addition, combining exposure to long days with twice-daily milking will increase further milk yield in such goats without affecting milk components.  相似文献   
57.
The aims of our study were to compare the effectiveness of poultry manure (PM) and banana waste (BW), with regard to their use as inoculant carriers of a bacterial consortium constituted by strains of Azospirillum, Azotobacter and P-solubiliser bacteria and to establish the most efficient dose of biofertilizer for a soil cultivated with banana (Musa paradisiaca AAA Simmonds), with respect to improving plant performance and soil physical and microbiological properties. Six months after planting, plant growth had increased with increase in dose of the biofertilizers applied. The biofertilizer prepared on BW enhanced the density of P-solubiliser bacteria, the concentrations of available P and foliar P to a greater extent than with the biofertilizer prepared on PM. The increases produced by the biofertilizer prepared on PM for the soil aggregate stability, enzymatic activities and the labile carbon fractions were highly correlated to the dose applied. Both biofertilizers can be considered potentially useful as inoculant carriers of PGPR but the usefulness of BW appears to be restricted to moderate doses of application (≤3%).  相似文献   
58.
    
The main aim of this paper was to determine the rate of erosion and aggradation within a forest road on different geological structures as well as a comparison of changes between roadbeds and road cutslopes. The research was conducted in the Lejowa Valley in the Tatra Mountains. The measurements of the forest road were performed using a Leica ScanStation C10 terrestrial laser scanner (TLS) with a set of six-inch Leica High Definition Survey (HDS) targets. Based on the multi-temporal digital elevation models (DEMs) two DEM of Differences (DoD) were created for the summer season of 2019 and the 2019–2020 period. The research has shown that there is a significant difference between the rate of relief change for roads constructed atop conglomerates and limestone. The net change for the road within conglomerates was an erosion of 432.37 m3ha-1 yr-1, while for the road within limestone it was a sediment deposition which amounted to 3.87 m3ha-1 yr-1. Research has shown that there exists a difference in the rate of erosion for road cutslopes and roadbeds constructed within conglomerates. It was shown that the erosion rate for the roadbeds was 1.7-times larger than that for the studied road cutslopes in the period 2019–2020. Improperly designed and constructed forest roads may be subject to intensive relief transformations, even after they are no longer in use.  相似文献   
59.
    
Cefquinome is a fourth‐generation cephalosporin that is used empirically in goats. Different physiologic factors like pregnancy or lactation could determine the pharmacokinetic behavior of drugs in the organism. The objectives of this study are to (a) compare the pharmacokinetics of cefquinome after intravenous and intramuscular administration in adult nonpregnant (n = 6), pregnant (n = 6), and lactating goats (n = 6), at a dose of 2 mg/kg, with rich sampling by nonlinear mixed‐effects modeling, (b) conduct a pharmacokinetic/pharmacodynamic analysis to evaluate the efficacy of the recommended posology in goats with different physiological states, and (c) determine the optimal posology that achieve a PTA value ≥ 90%, taking into account a T > MIC ≥ 60% of a MIC value ≤ 0.25 µg/ml, in the different subpopulations of goats for both routes. Gestation significantly increased Ka and V1, while reduced F0, Cl, and Q. On the other hand, lactation significantly increased V1 and reduced Tk0. Cefquinome concentrations achieved in placental cotyledon, amniotic fluid, and fetal serum indicate a minimal penetration across the placental barrier. Moreover, milk penetration of cefquinome was minimal. The total body clearance of cefquinome for goats was 0.29 L kg?1 hr?1, that is apparently higher than the reported for cows (0.13 L kg?1 hr?1) and pigs (0.16 L kg?1 hr?1). So, the optimal dose regimen for cefquinome after intravenous and intramuscular administration required higher dose and frequency of administration compared with recommendations for cows or pigs. Therefore, 2 mg kg?1 8 hr?1 and 5 mg kg?1 12 hr?1 could be used for IV and IM routes, respectively, for the treatment of respiratory infections caused by P. multocida and M. haemolytica, but only 5 mg kg?1 12 hr?1 by both routes should be recommended for Escherichia coli infections.  相似文献   
60.
    
In recent decades, distributed temperature sensing (DTS) has emerged as a robust technology for environmental applications, enabling high-resolution temperature measurements along fibre optic cables (FOCs). The actively heated fibre optic (AHFO) method is employed to monitor soil moisture (θ$$ theta $$, m3 m−3), wherein the soil temperature subsequent to the application of a heat pulse is measured by a DTS (AHFO-DTS approach). Despite significant improvements in the application of AHFO-DTS under controlled and natural conditions, the thermal behaviour of soil during multiple saturation–natural drying cycles has been insufficiently evaluated. This study aimed to address this gap by constructing an experimental horizontal soil profile in the laboratory for the application of the AHFO-DTS method during two successive saturation–drainage–evaporation (SDE) cycles. Three heating strategies were applied to a metallic alloy in contact with a FOC, and calibration models were used to correlate θ$$ theta $$ with the thermal conductivity (λ$$ lambda $$), cumulative temperature increase (Tcum$$ {T}_{mathrm{cum}} $$), and maximum temperature increase (Tmax$$ {T}_{mathrm{max}} $$). The results indicated that during the second SDE cycle, the highest errors in θ$$ theta $$ estimates were observed with the low power-short heat pulse, whereas the application of the low power-long duration and high power-short duration pulses improved the accuracy of calculations. Additionally, errors in θ$$ theta $$ estimates escalated under wetter conditions, attributed to a shift in soil heat transfer capacity from the first to the second SDE cycle for θ$$ theta $$ > 0.10 m3 m−3. This behaviour was ascribed to thermal hysteresis, arising from the contact resistance of the FOC and the alloy with the surrounding soil. Furthermore, the Tmax$$ {T}_{mathrm{max}} $$ method exhibited the least sensitivity to this effect and yielded reliable θ$$ theta $$ estimates, thus its adoption is recommended. Moreover, the use of the low power-long duration heating strategy is suggested as it promotes a trade-off between energy saving and accurate estimates. We concluded that assessing soil thermal response under multiple SDE cycles enhances the comprehension of the AHFO-DTS method. Overall, our findings provide insights into enhancing the applicability of this approach under field conditions, particularly following irrigation schedules and natural rainfall events.  相似文献   
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