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91.
The objectives of this study were to evaluate the performance of the cropping system model (CSM)-CERES-Rice to simulate growth and development of an aromatic rice variety under irrigated conditions in a semiarid environment of Pakistan and to determine the impact of various plant densities and nitrogen (N) application rates on grain yield and economic return. The crop simulation model was evaluated with experimental data collected in experiments that were conducted in 2000 and 2001 in Faisalabad, Punjab, Pakistan. The experimental design was a randomized complete block design with three replications and included three plant densities (one seedling hill−1, PD1; two seedlings hill−1, PD2; and three seedlings hill−1, PD3) and five N fertilizer regimes (control, N0; 50 kg ha−1, N50; 100 kg ha−1, N100; 150 kg ha−1, N150; and 200 kg ha−1, N200). To determine the most appropriate combination of plant density and N levels, four plant densities from one seedling hill−1 to four seedlings hill−1 and 13 N levels ranging from 0 to 300 kg N ha−1 (52 scenarios) were simulated for 35 years of historical daily weather data under irrigated conditions. The evaluation of CSM-CERES-Rice showed that the model was able to simulate growth and yield of irrigated rice in the semiarid conditions, with an average error of 11% between simulated and observed grain yield. The results of the stimulation analysis result showed that two seedlings hill−1 along with 200 kg N ha−1 (PD2N200) produced the highest yield as compared to all other scenarios. Furthermore, the economic analysis through the mean gini dominance also showed the dominance of this treatment (PD2N200) compared to the other treatment combinations. Thus, the management scenario that consisted of two seedlings hill−1 and 200 kg N ha−1 was the best for high yield and monitory return of irrigated rice in the semiarid environment. The mean monetary returns ranged from 291 US $ ha−1 to 1 460 US $ ha−1 to 1 460 US  ha−1 among the 52 production options that were simulated. This approaching was demonstrated as effective way to optimize the density and N management for high yield and monetary return. It will help the rice production.  相似文献   
92.
Milk heated to 75 and 85 degrees C in a water bath or in a microwave oven was assayed for changes in salt partitioning after cooling to room temperature. To properly to assess differences and draw valid comparisons, the two heating methods used in the experiment were applied to samples for identical exposure times, and the samples were heated to attain the same final temperatures. Although the soluble Ca and P(i) contents were lower in the heated milk samples, no significant differences in salt partitioning were found between microwave and conventional heating. Ionic calcium levels in the milk samples pasteurized using microwave energy were very close to the levels in the samples heated in a conventional water bath (approximately 90% of the level in the untreated milk samples). The microwave heating-induced changes were completely reversed after storage at 20 degrees C for 24 h. The coagulation properties of the heated milk samples were also examined, and the coagulation time was longer and the curd formation rate slower in the microwave-heated milk than in the raw milk. Still, the experimental results demonstrated that microwave heating was no more detrimental to the milk than conventional heating and could thus be used for pasteurization purposes.  相似文献   
93.

Two Asian longhorn beetles, Anoplophora glabripennis and Anoplophora chinensis, are among the most serious alien invasive species attacking forest and urban trees, both in North America and Europe. Major efforts have been put into preventing further entry and establishment of the two species as well as promoting their successful eradication. Here, we review these efforts, their progress and outcome, and scientific advancements in monitoring and control methods. The combined international activities and harmonizing legislative changes in detection and eradication methods have proven worthwhile, with more than 45% of eradication programmes successful in the last 12 years. Some countries were able to completely eradicate all populations and others managed to reduce the area affected. Although the costs of the eradication programmes can be very high, the benefits outweigh inaction. Attempts to eradicate A. chinensis have been more challenging in comparison with those targeting A. glabripennis. For both species, efforts are hampered by the ongoing arrival of new beetles, both from their native regions in Asia and from other invaded regions via bridgehead effects. The methods used for eradication have not changed much during the last decade, and host removal is still the method most commonly used. On the other hand, detection methods have diversified during the last decade with advances in semiochemical research and use of detection dogs. The next decade will determine if eradications continue to be successful, particularly in the case of A. chinensis, which has been targeted in some countries for containment instead of eradication.

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94.
Poultry feed is at the start of the food safety chain in the "farm-to-fork" model, and might serve as a source of antimicrobial resistant bacteria present in poultry meat. Antimicrobial resistance was investigated in 1137 enterococci and 163 Escherichia coli strains recovered from 23 samples of commercial broiler feed and 66 samples of raw feeding materials taken over half a year timespan. Enumeration of enterococci and E. coli were also performed using traditional plating and fluorescent in situ hybridisation methods. Viable enterococci were detected in all feed samples and in 66% of samples of separate feed ingredients, while E. coli was present in 50% and 32% of feed and raw feeding materials, respectively. The median values (50th percentile) for plate and FISH counts for feeds were, respectively, 2.70 log CFU/g and 5.52 log cells/g for enterococci, and 0.15 log CFU/g and 6.00 log cells/g for E. coli. Among enterococci recovered from feed ingredients, resistance to rifampicin, erythromycin, nitrofurantoin, tetracycline, and ciprofloxacin was found in 59.8%, 21.6%, 21.2%, 18.0% and 6.9% of the isolates, respectively. A considerable proportion of the enterococci isolates obtained from broiler feed displayed resistance to tetracycline (69.1%), rifampicin (58.5%), erythromycin (52.9%) and nitrofurantoin (36.2%). Lower percentage of resistance was observed to chloramphenicol (4.6%), ciprofloxacin (3.9%), vancomycin (1.9%) and ampicillin (1.2%). Among E. coli recovered from feed ingredients and poultry feeds, resistance to ampicillin, tetracycline and streptomycin was found in 22.9%, 27.6% and 19.0% and in 22.4%, 41.4% and 17.0% of the isolates, respectively. These data show that feedstuffs and poultry feeds are extensively contaminated by resistant enterococci and, in a lesser extent, by E. coli, thus leading to their introduction in the farm environment.  相似文献   
95.
Continued contact between humans and animals, in combination with the ever-increasing movement of human and animal populations that is one effect of globalization, contributes to the spread of diseases, often with detrimental effects on public health. This has led professionals involved in both animal health and public health to recognize veterinary public health (VPH) as a key area for their activities to address the human-animal interface. Veterinarians, a profession with major involvement in this field, are in need of specific knowledge and skills to prevent and control public-health problems. As a result, VPH must be directly integrated into veterinary educational programs. At present, only few veterinary schools have specific VPH programs; in most institutions, VPH does not feature as a specific subject in either undergraduate or post-graduate curricula. SAPUVET and SAPUVETNET II are network projects supported by the ALFA program of the European Union (EU). Their main objectives are to reach a common understanding between European and Latin American universities in the definition of the areas in which VPH is important in their respective countries, and to design a harmonized training program for veterinarians in VPH, by making use of new technological applications and innovative teaching methodologies. The elaboration of educational material in combination with case studies presenting real-life problems provides a basis to apply the knowledge acquired on VPH. It is envisaged that the material and modules developed during the two projects will be integrated into the veterinary curricula of the participating universities, as well as in other partner organizations.  相似文献   
96.
Arbuscular mycorrhizal (AM) fungi are key organisms of the soil/plant system, influencing soil fertility and plant nutrition, and contributing to soil aggregation and soil structure stability by the combined action of extraradical hyphae and of an insoluble, hydrophobic proteinaceous substance named glomalin-related soil protein (GRSP). Since the GRSP extraction procedures have recently revealed problems related to co-extracting substances, the relationship between GRSP and AM fungi still remains to be verified. In this work the hypothesis that GRSP concentration is positively correlated with the occurrence of AM fungi was tested by using Medicago sativa plants inoculated with different isolates of Glomus mosseae and Glomus intraradices in a microcosm experiment. Our results show that (i) mycorrhizal establishment produced an increase in GRSP concentration - compared to initial values - in contrast with non-mycorrhizal plants, which did not produce any change; (ii) aggregate stability, evaluated as mean weight diameter (MWD) of macroaggregates of 1-2 mm diameter, was significantly higher in mycorrhizal soils compared to non-mycorrhizal soil; (iii) GRSP concentration and soil aggregate stability were positively correlated with mycorrhizal root volume and weakly correlated with total root volume; (iv) MWD values of soil aggregates were positively correlated with values of total hyphal length and hyphal density of the AM fungi utilized.The different ability of AM fungal isolates to affect GRSP concentration and to form extensive and dense mycelial networks, which may directly affect soil aggregates stability by hyphal enmeshment of soil particles, suggests the possibility of selecting the most efficient isolates to be utilized for soil quality improvement and land restoration programs.  相似文献   
97.

Background

Graham Little – Piccardi – Lassueur (GLPL) syndrome is a rare dermatosis characterized by scarring alopecia, loss of pubic and axillary hair, and progressive development of variously located follicular papules. We report a first case ever of an autoimmune response in a patient suffering from GLPL syndrome.

Methods

Immunofluorescence and immunoblot analysis were used in a variety of cell cultures including human, monkey, hamster, mouse and bovine cells to analyze the presence of autoantibodies in a GLPL patient.

Results

The autoimmune serum showed a pattern of centromere and spindle microtubule staining resembling that of the chromosomal passenger protein complex. By using a complex of proteins expressed in baculovirus, immunoblot analysis demonstrated that the INCENP protein is a major autoantigen in this patient with GLPL syndrome.

Conclusion

An autoimmune response in GLPL syndrome is reported against the INCENP centromere protein. The occasional development of autoimmunity in GLPL patients could serve as a test in continuing efforts to detect this disease and for a more directed therapy based on the autoantigen response.
  相似文献   
98.
The Northern Adriatic Sea is the area of the Mediterranean Sea where eutrophication and episodes related to harmful algae have occurred most frequently since the 1970s. In this area, which is highly exploited for mollusk farming, the first occurrence of human intoxication due to shellfish consumption occurred in 1989, nearly 10 years later than other countries in Europe and worldwide that had faced similar problems. Until 1997, Adriatic mollusks had been found to be contaminated mostly by diarrhetic shellfish poisoning toxins (i.e., okadaic acid and dinophysistoxins) that, along with paralytic shellfish poisoning toxins (i.e., saxitoxins), constitute the most common marine biotoxins. Only once, in 1994, a toxic outbreak was related to the occurrence of paralytic shellfish poisoning toxins in the Adriatic coastal waters. Moreover, in the past 15 years, the Adriatic Sea has been characterized by the presence of toxic or potentially toxic algae, not highly widespread outside Europe, such as species producing yessotoxins (i.e., Protoceratium reticulatum, Gonyaulax spinifera and Lingulodinium polyedrum), recurrent blooms of the potentially ichthyotoxic species Fibrocapsa japonica and, recently, by blooms of palytoxin-like producing species of the Ostreopsis genus. This review is aimed at integrating monitoring data on toxin spectra and levels in mussels farmed along the coast of the Emilia-Romagna region with laboratory studies performed on the species involved in the production of those toxins; toxicity studies on toxic or potentially toxic species that have recently appeared in this area are also reviewed. Overall, reviewed data are related to: (i) the yessotoxins producing species P. reticulatum, G. spinifera and L. polyedrum, highlighting genetic and toxic characteristics; (ii) Adriatic strains of Alexandrium minutum, Alexandrium ostenfeldii and Prorocentrum lima whose toxic profiles are compared with those of strains of different geographic origins; (iii) F. japonica and Ostreopsis cf. ovata toxicity. Moreover, new data concerning domoic acid production by a Pseudo-nitzschia multistriata strain, toxicity investigations on a Prorocentrum cf. levis, and on presumably ichthyotoxic species, Heterosigma akashiwo and Chattonella cf. subsalsa, are also reported.  相似文献   
99.
Neuroblastoma (NB) is a common cancer in childhood, and lethal in its high-risk form, primarily because of its high metastatic potential. Targeting cancer cell migration, and thus preventing metastasis formation, is the rationale for more effective cancer therapy against NB. Previous studies have described the leaf extract from Posidonia oceanica marine plant (POE) as an antioxidant, anti-inflammatory agent and inhibitor of cancer cell migration. This study aims to examine the POE anti-migratory role in human SH-SY5Y neuroblastoma cells and the underlying mechanisms of action. Wound healing and gelatin zymography assays showed that POE at early times inhibits cell migration and reduces pro-MMP-2 release into culture medium. By monitoring expression level of key autophagy markers by Western blot assay, a correlation between POE-induced cell migration inhibition and autophagy activation was demonstrated. Cell morphology and immunofluorescence analyses showed that POE induces neurite formation and neuronal differentiation at later times. These results suggest POE might act against cell migration by triggering early nontoxic autophagy. The POE-induced cellular morphological change toward cell differentiation might contribute to prolonging the phytocomplex anti-migratory effect to later times. Overall, these results encourage future in vivo studies to test POE applicability in neuroblastoma treatment.  相似文献   
100.
ABSTRACT: This study shows that high pathogenic H5N1 influenza virus infection of chicken induced high levels of bioactive interferon type I in the lung (4.3 × 105 U/mg tissue), plasma (1.1 × 105 U/mL), and spleen (9.1 × 105 U/mg tissue). In contrast, a low pathogenic attenuated H5N1 vaccine strain only induced approximately 24 times less IFN in the lung, 441 times less in the spleen and 649 less in the plasma. This was in the same range as a reassortant carrying the HA from the vaccine strain and the remaining genes from the high pathogenic virus. On the other hand, a reassortant virus with the HA from the high pathogenic H5N1 with the remaining genes from the vaccine strain had intermediate levels of IFN. The level of interferon responses related to the viral load, and those in the spleen and blood to the spread of virus to lymphoid tissue, as well as disease severity. In vitro, the viruses did not induce interferon in chicken embryonic fibroblasts, but high levels in splenocytes, with not clear relationship to pathogenicity and virulence. This, and the responses also with inactivated viruses imply the presence of plasmacytoid dendritic cell-like leukocytes within the chicken immune system, possibly responsible for the high interferon responses during H5N1 infection. Our data also indicate that the viral load as well as the cleavability of the HA enabling systemic spread of the virus are two major factors controlling systemic IFN responses in chicken.  相似文献   
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