Roasting effects on formation mechanisms of coffee brew melanoidins     

Bekedam EK  Loots MJ  Schols HA  Van Boekel MA  Smit G 《Journal of agricultural and food chemistry》2008,56(16):7138-7145

The effect of the roasting degree on coffee brew melanoidin properties and formation mechanisms was studied. Coffee brew fractions differing in molecular weight (Mw) were isolated from green and light-, medium-, and dark-roasted coffee beans. Isolated fractions were characterized for their melanoidin, nitrogen, protein, phenolic groups, chlorogenic acid, quinic acid, caffeic acid, and sugar content. It was found that the melanoidin level in all fractions correlated with both the nitrogen and the protein content. The melanoidin level also correlated with the phenolic groups' level and ester-linked quinic acid level. It was concluded that proteins and chlorogenic acids should be primarily involved in melanoidin formation. Initial roasting, from green to light-roasted beans, especially led to the formation of intermediate Mw (IMw) melanoidins when compared to high Mw (HMw) melanoidins. Indications were found that this IMw melanoidin formation is mainly due to Maillard reactions and chlorogenic acid incorporation reactions between chlorogenic acids, sucrose, and amino acids/protein fragments. Additionally, it was found that prolonged roasting predominantly led to formation melanoidins with a high Mw. Furthermore, arabinogalactans seem to be relatively more involved in melanoidin formation than galactomannans. It was hypothesized that chromophores may be formed or attached through the arabinose moiety of arabinogalactan proteins (AGP). Finally, it could be concluded that galactomannans are continuously incorporated in AGP-melanoidins upon roasting.  相似文献   

Evaluation of NASA satellite- and assimilation model-derived long-term daily temperature data over the continental US   总被引：2，自引：0，他引：2  

Jeffrey W. White  Gerrit Hoogenboom  Paul W. Stackhouse Jr.  James M. Hoell 《Agricultural and Forest Meteorology》2008,148(10):1574-1584

Agricultural research increasingly is expected to provide precise, quantitative information with an explicit geographic coverage. Limited availability of daily meteorological records often constrains efforts to provide such information through use of simulation models, spatial analysis, and related decision support tools. The Prediction Of Worldwide Energy Resources (NASA/POWER) project at the NASA Langley Research Center provides daily data globally for maximum and minimum temperatures and other weather variables on a 1° latitude–longitude grid. The data are assembled from a range of products derived from satellite imagery, ground observations, windsondes, modeling and data assimilation. Daily temperature data from NASA/POWER for 1983 to 2004 for the continental US were compared with data of 855 individual ground stations from the National Weather Service Cooperative Observer Program (COOP). Additionally, a wheat (Triticum aestivum L.) simulation model was used to compare predicted time to anthesis using the two data sources. Comparisons of daily maximum temperatures (T_max) gave an r²-value of 0.88 (P < 0.001) and root-mean-squared error (RMSE) of 4.1 °C. For minimum temperature (T_min), the r²-value was 0.88 (P < 0.001) and RMSE, 3.7 °C. Mean values of T_max, and T_min from NASA/POWER were, respectively, 2.4 °C cooler and 1.1 °C warmer than the COOP data. Differences in temperature were least during summer months. When data were aggregated over periods of 8 days or more, the RMSE values declined to below 2.7 °C for T_max and T_min. Simulations of time to anthesis with the two data sources were also strongly correlated (r² = 0.92, P < 0.001, RMSE = 14.5 d). Anthesis dates of winter wheat regions showed better agreement than southern, winter-grown spring wheat regions. The differences between the data sources were associated with differences in elevation, which in large part resulted from NASA/POWER data being based on mean elevations over a 1° grid cells vs. COOP data corresponding to the elevation of specific stations. Additional sources of variation might include proximity to coastlines and differences in observation time, although these factors were not quantified. Overall, if mountainous and coastal regions are excluded, the NASA/POWER data appeared promising as a source of continuous daily temperature data for the USA for research and management applications concerned with scales appropriate to the 1° coordinate grid. It further appeared that the POWER data could be improved by adjusting for elevation (lapse rate) effects, reducing seasonal bias, and refining estimation of actual maximum and minimum temperatures in diurnal cycles.  相似文献   

Optimizing Parameters of CSM-CERES-Maize Model to Improve Simulation Performance of Maize Growth and Nitrogen Uptake in Northeast China   总被引：1，自引：0，他引：1  

LIU Hai-long  YANG Jing-yi  HE Ping  BAI You-lu  JIN Ji-yun  Craig F Drury  ZHU Ye-ping  YANGXue-ming  LI Wen-juan  XIE Jia-gui  YANG Jing-min  Gerrit Hoogenboom 《中国农业科学(英文版)》2012,(11):1898-1913

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Diurnal patterns in dispersal of Monilinia fructigena conidia in an apple orchard in relation to weather factors     

Finian Bannon  Gerrit Gort  Gerard van Leeuwen  Imre Holb  Mike Jeger 《Agricultural and Forest Meteorology》2009,149(3-4):518-525

The aerial concentration of Monilinia fructigena (causing brown rot in pome fruit) conidia was sampled during 1997 and 1998 in an apple orchard and was related to weather conditions. The highest hourly concentration measured in 1997 was 230 conidia/m³, in 1998 concentrations were lower than in 1997 throughout the season. In both years concentrations were highest in the afternoon hours. Generalised linear models, employing a Poisson distribution for the spore counts and a logarithm link function, were used to study the relationships between spore counts and lagged weather variables. In 1997 the best fitting model had variables temperature lagged at 100 h, an east–west component of wind direction, and wind speed; whereas in 1998 the best model included in addition an effect of relative humidity. Temperature and wind direction had consistent effects on hourly spore counts in both years, but whereas temperature has a biologically relevant effect on spore production and maturation, the effect of wind direction is likely to reflect the purely local effect of orchard layout. Results are compared with observations made in stone fruit orchards where Monilinia laxa and Monilinia fructicola are the predominant species, and differences in epidemiology between these systems are discussed.  相似文献   

Plasma chemistry reference values from captive red-legged partridges (Alectoris rufa)     

Rodríguez P  Tortosa FS  Millán J  Gortázar C 《British poultry science》2004,45(4):565-567

1. Haematological and plasma biochemical parameters of 66 captive red-legged partridges (Alectoris rufa) of both sexes were analysed in order to determine reference values, taking sex and age into account. 2. There were no statistically significant differences in haematocrit, plasma glucose content or creatine kinase activity either with age or between sexes. 3. Plasma cholesterol concentrations showed differences between sexes, whereas the plasma concentrations of urea, uric acid and creatinine were significantly affected by age. 4. Plasma triglyceride and total protein concentrations were affected by both sex and age. 5. A peak at 6 months old in those parameters related to protein metabolism, such as urea, uric acid and creatinine may be related to the end of the growing period and the start of ovulation after moulting.  相似文献   

Epidemiological study on porcine circovirus type 2 (PCV2) infection in the European wild boar (Sus scrofa)     

Vicente J  Segalés J  Höfle U  Balasch M  Plana-Durán J  Domingo M  Gortázar C 《Veterinary research》2004,35(2):243-253

Porcine circovirus type 2 (PCV2) is considered as the causative agent of postweaning multisystemic wasting syndrome (PMWS) in domestic pigs, where the virus is ubiquitous as evidenced by serological surveys. We present the results of the first nationwide sero-survey on the presence of PCV2 antibodies in European wild boars, and report the first PMWS case in a wild boar from Spain. Sera from 656 hunter harvested wild boars from 45 different geographical sites and 22 additional imported animals were analysed by means of an immunoperoxidase monolayer assay (IPMA). We also examined the tissues from 55 healthy and one diseased wild boars for the presence of PCV2 nucleic acid and PMWS lesions by in situ hybridisation and histopathology, respectively. Additionally, abundance estimates of wild boars and field interviews were carried out on 30 sampling sites. The prevalence of medium to high PCV2 serological titres among the examined wild boars was 47.89 +/- 1.9%. Seropositive wild boars appeared in all but one of the geographical regions analysed. Seroprevalence and titre of PCV2 antibodies were closely related to the management of the wild boar populations. Wild boars from intensively managed, farm-like populations had higher prevalence than wild boars living in more natural situations. The effect of wild boar abundance and management on PCV2 antibody prevalence was further evidenced by the high correlation existing between the relative abundance estimates of animals and the percentage of wild boars with medium to high levels of PCV2 antibodies. PCV2 nucleic acid was detected in the tissues of three wild boars. One of these was diagnosed as PMWS. The results, in addition to information on piglet mortalities, suggest a potential role of PMWS in piglet mortality in intensively managed wild boar populations.  相似文献   

Systemic AA-amyloidosis in a European wild boar (Sus scrofa) suffering from generalized tuberculosis     

Segalés J  Vicente J  Luján L  Toussaint MJ  Gruys E  Gortázar C 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2005,52(3):135-137

Summary An adult female wild boar (Sus scrofa) was found moribund in Cabaneros National Park (central Spain). The animal had a markedly emaciated carcass, with body weight of 25.9 kg. At necropsy, most of the parenchymatous organs had widespread variably sized granulomas. Generalized tuberculosis was confirmed by PCR detection of Mycobacterium bovis in the mandibular lymph node. Large amounts of a hyaline, pale eosinophilic material were observed in liver, kidney and intestine. Congo red staining and green birefringence identified amyloid, which was further classified as AA type based on immunohistochemical results. It is speculated that the abundant serum amyloid A derivatives deposited in the tissues as AA-amyloid may be associated with the generalized tuberculosis. This is the first report of amyloidosis in the European wild boar.  相似文献   

Genetic diversity of anaplasma species major surface proteins and implications for anaplasmosis serodiagnosis and vaccine development     

de la Fuente J  Lew A  Lutz H  Meli ML  Hofmann-Lehmann R  Shkap V  Molad T  Mangold AJ  Almazán C  Naranjo V  Gortázar C  Torina A  Caracappa S  García-Pérez AL  Barral M  Oporto B  Ceci L  Carelli G  Blouin EF  Kocan KM 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2005,6(1):75-89

The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several pathogens of veterinary and human medical importance. An understanding of the diversity of Anaplasma major surface proteins (MSPs), including those MSPs that modulate infection, development of persistent infections, and transmission of pathogens by ticks, is derived in part, by characterization and phylogenetic analyses of geographic strains. Information concerning the genetic diversity of Anaplasma spp. MSPs will likely influence the development of serodiagnostic assays and vaccine strategies for the control of anaplasmosis.  相似文献   

Etiology of asparagus replant-bound early decline     

Wim J. Blok  Gerrit J. Bollen 《European journal of plant pathology / European Foundation for Plant Pathology》1996,102(1):87-98

Asparagus replant-bound early decline (ARED) was characterized and its etiology was elucidated in experiments under greenhouse and field conditions. Selective soil treatments were used to differentiate between autotoxic compounds and soil-borne pathogens as causal agents. In greenhouse experiments, there were symptoms of ARED within 12—15 weeks. Asparagus plants grown in soil formerly used for asparagus (asparagus soil) showed brown lesions on primary and secondary roots, and many secondary roots had rotted. Root weights of plants grown in asparagus soil were lower than those of plants grown in fresh soil.Fusarium oxysporum f. sp.asparagi (Foa) was by far the most common species among the fungi isolated from roots with lesions. Under greenhouse and field conditions, there were similar symptoms, which indicates that the results obtained under greenhouse conditions are similar to those in the field. The vertical distribution of the ARED-causing factor(s) was studied in a greenhouse experiment in which plants were grown in soil from three layers: 0–30, 30–60, and 60–90 cm. For all four asparagus soils tested, there were ARED symptoms and similar disease severity in samples from all three depths. The causal factor persisted at least 11 years after soil was no longer used for asparagus. When asparagus soil was diluted with fresh soil to give mixtures with 100%, 80%, 50%, 20% and 0% asparagus soil, disease severity did not decrease with increasing dilution of the asparagus soil from 100% to 20%. Disease severity of all mixtures with asparagus soil was significantly higher than that for fresh soil. The results imply that ARED is caused by a pathogen colonizing the soil rather than inhibition by autotoxins released from residues of the preceding asparagus crop. This conclusion is supported by the results of greenhouse and outdoor experiments with heat and fungicide treatments of soil. ARED was nullified by heat treatments of 30 min at 55 or 60 °C but not 45 and 50 °C, eliminating autotoxins as an important cause of ARED because they are heat-stable. Foa is eliminated by a 30-min soil treatment at 55–60 °C but not 50 °C. Prochloraz, known for its toxicity toF. oxysporum, also nullified ARED. Disease severity level was related to the density of Foa in soil. The results provide conclusive evidence thatF. oxysporum f. sp.asparagi is the main cause of ARED in the Netherlands, which largely removes the need to discriminate between early decline and replant-bound early decline, because Foa is the main cause of both diseases.  相似文献   

Transportation of animals and emergency slaughtering: what are the rules?     

de Groot H  Hooijer G 《Tijdschrift voor diergeneeskunde》2008,133(6):244-248

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