Classification of cereal flours by chemometric analysis of MIR spectra     

Cocchi M  Foca G  Lucisano M  Marchetti A  Pagani MA  Tassi L  Ulrici A 《Journal of agricultural and food chemistry》2004,52(5):1062-1067

Different kinds of cereal flours submitted to various technological treatments were classified on the basis of their mid-infrared spectra by pattern recognition techniques. Classification in the wavelet domain was achieved by using the wavelet packet transform for efficient pattern recognition (WPTER) algorithm, which allowed singling out the most discriminant spectral regions. Principal component analysis (PCA) on the selected features showed an effective clustering of the analyzed flours. Satisfactory classification models were obtained both on training and test samples. Furthermore, mixtures of varying composition of the studied flours were distributed in the PCA space according to their composition.  相似文献   

Corrigendum to “Predictability and uncertainty of the soil erodibility factor using a global dataset” [Catena 31 (1997) 1–22] and to “Erratum to Predictability and uncertainty of the soil erodibility factor using a global dataset” [Catena 32 (1998) 307–308]     

Dino Torri  Jean Poesen  Lorenzo Borselli 《CATENA》2002,46(4):309

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Usefulness of amino acid composition to discriminate between honeydew and floral honeys. Application to honeys from a small geographic area     

Iglesias MT  De Lorenzo C  Del Carmen Polo M  Martín-Alvarez PJ  Pueyo E 《Journal of agricultural and food chemistry》2004,52(1):84-89

With the aim of finding methods that could constitute a solid alternative to melissopalynological and physicochemical analyses to determine the botanical origin (floral or honeydew) of honeys, the free amino acid content of 46 honey samples has been determined. The honeys were collected in a small geographic area of approximately 2000 km(2) in central Spain. Twenty-seven honey samples were classified as floral and 19 as honeydew according to their palynological and physicochemical analyses. The resulting data have been subjected to different multivariant analysis techniques. One hundred percent of honey samples have been correctly classified into either the floral or the honeydew groups, according to their content in glutamic acid and tryptophan. It is concluded that free amino acids are good indicators of the botanical origin of honeys, saving time compared with more tedious analyses.  相似文献   

Effect of olive ripening degree on the oxidative stability and organoleptic properties of cv. Nostrana di Brisighella extra virgin olive oil     

Rotondi A  Bendini A  Cerretani L  Mari M  Lercker G  Toschi TG 《Journal of agricultural and food chemistry》2004,52(11):3649-3654

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Biochemical and molecular analysis of carotenoid biosynthesis in flavedo of orange (Citrus sinensis L.) during fruit development and maturation   总被引：8，自引：0，他引：8  

Rodrigo MJ  Marcos JF  Zacarías L 《Journal of agricultural and food chemistry》2004,52(22):6724-6731

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Spectroscopic detection of forest diseases:a review (1970-2020)     

Lorenzo Cotrozzi 《林业研究》2022,33(1):21-38

Sustainable forest management is essential to confront the detrimental impacts of diseases on forest eco-systems.This review highlights the potential of vegetation spectroscopy in improving the feasibility of assessing forest disturbances induced by diseases in a timely and cost-effec-tive manner.The basic concepts of vegetation spectroscopy and its application in phytopathology are first outlined then the literature on the topic is discussed.Using several opti-cal sensors from leaf to landscape-level,a number of for-est diseases characterized by variable pathogenic processes have been detected,identified and quantified in many coun-try sites worldwide.Overall,these reviewed studies have pointed out the green and red regions of the visible spec-trum,the red-edge and the early near-infrared as the spectral regions most sensitive to the disease development as they are mostly related to chlorophyll changes and symptom develop-ment.Late disease conditions particularly affect the short-wave-infrared region,mostly related to water content.This review also highlights some major issues to be addressed such as the need to explore other major forest diseases and geographic areas,to further develop hyperspectral sensors for early detection and discrimination of forest disturbances,to improve devices for remote sensing,to implement long-term monitoring,and to advance algorithms for exploitation of spectral data.Achieving of these goals will enhance the capability of vegetation spectroscopy in early detection of forest stress and in managing forest diseases.  相似文献   

Aspectos Cronologicos en la Maduracion Nuclear de Oocitos Bovinos Cultivados in vitro     

P. Lorenzo    M. J. Illera    J. C. Illera  M. Illera 《Anatomia, histologia, embryologia》1995,24(2):139-144

In this study, the chronological changes in the meiotic progress of in vitro maturation of bovine oocytes was analysed. Oocytes (n = 1044) were obtained from a local abbatoir and were classified into two groups according to the presence or absence of cumulus cells. They were incubated in microdrops (5 per drop) in TCM-199 (control), TCM-199 + 10% fetal calf serum (treatment 2) and TCM-199 + 10% estrous cow serum (treatment 3). Oocytes were fixed and stained at the end of 0, 6, 12, 18, 24 and 30h of the beginning of in vitro culture, were evaluated according to the nuclear stage of maturation. These results demonstrated that the immature oocytes at the time of collection (0 h) were in the germinal vesicle stage (GV), and that the highest maturation rate was at 24 h of culture in all treatments. Serum treatments enhanced the maturation rates obtained (52.1 and 55.7%) compared to control (serum-free) medium (42.7%; P<0.05) in cumulus-cell-enclosed oocytes. In denuded oocytes, the maturation rates were lower compared to cumulus-cells-enclosed oocytes in all treatments. In conclusion, meiotic progression of bovine oocytes can be influenced by the inclusion of sera in the maturation media and by the presence of the cumulus cells.  相似文献   

Sampling Shrimp Populations in Hatcheries     

Lorenzo M.  Juarez Allan H.  Luxem  David B.  Rouse 《Journal of the World Aquaculture Society》1996,27(2):218-222

Abstract.– Shrimp populations were estimated with volumetric sampling techniques during different phases of hatchery operations. Factors considered which might effect precision of estimates included stage age, density and temperature. Estimates of nauplii were obtained with coefficient of variation values smaller than 3% when nauplii were concentrated in 20-L buckets and smaller than 8% when released in 13,000 L of water in larval rearing tanks. In both cases estimates were of sufficient precision to make management decisions for routine hatchery work. A technique was developed for estimating shrimp populations in larval rearing tanks with coefficient of variation values smaller than 15%. Volumetric sampling of postlarvae older than PL₄, in larval rearing tanks was highly variable due to the tendency of shrimp to congregate and attach to tank walls and bottoms. A direct relationship was observed between postlarval density and the precision of population estimates in harvest buckets. Water temperature and postlarval age did not affect precision at the densities and ages studied. These findings have important implications for commercial transactions. Industry standards utilizing coefficient of variation are recommended for larvae and postlarvae population estimates.  相似文献   

A PCR technique for the detection of Jaagsiekte sheep retrovirus in the blood suitable for the screening of ovine pulmonary adenocarcinoma in field conditions     

De Las Heras M  Ortín A  Salvatori D  Pérez de Villareal M  Cousens C  Miguel Ferrer L  Miguel Cebrián L  García de Jalón JA  Gonzalez L  Michael Sharp J 《Research in veterinary science》2005,79(3):201-264

Ovine pulmonary adenocarcinoma (OPA) is a naturally occurring contagious lung neoplasia caused by jaagsiekte sheep retrovirus (JSRV). Although no specific circulating antibodies against the virus can be detected in infected sheep, JSRV proviral DNA sequences can be found in peripheral blood leukocytes (PBLs) in clinically affected and in a proportion of in contact animals. In this study, existing hemi-nested PCR procedure is compared with a new one-step PCR technique that was developed to minimise potential DNA contamination and reduce sample and reagent handling. Different blood preparations were assessed and the best results were achieved on DNA prepared from buffy coat. The sensitivity of this PCR was lower in JSRV infected sheep without lesions of OPA than in clinically affected sheep, which indicate that this PCR may not be not fully appropriate for screening of individual sheep, but rather to provide results at flock level. This PCR is the only currently available blood test for detection of JSRV infected sheep and may be useful in epidemiological studies and in control programmes of OPA.  相似文献   

Comparison of blood and milk non-specific immune parameters in heifers after calving in relation to udder health     

Piccinini R  Binda E  Belotti M  Casirani G  Zecconi A 《Veterinary research》2005,36(5-6):747-757

A practical protocol to study udder immune status in field conditions was planned with the aim to assess different non-specific immune parameters in milk samples from dairy heifers during the periparturient period. Five herds located in northern Italy were selected and overall 39 heifers were enrolled in the trial. Milk samples were taken at 7, 14, 21, 28, 45, 60, and 75 days after calving. The parameters assessed were N-acetyl-beta-glucosaminidase (NAGase), lysozyme, respiratory burst (RB), somatic cell counts (SCC) and serum protein profile. SCC and NAGase were higher in the first sampling after calving, while lysozyme showed large variations during the observation period without a definite trend. The levels of RB observed in the first two weeks after calving, even if lower, were not statistically different from the values observed in samples taken over the following weeks. This study confirmed that the levels of immune components in milk are different from what is observed at blood level in the same cow. A significant decrease in RB in milk polymorphonuclear leukocytes (PMN) post-calving was not observed; milk PMN from healthy cows showed low RB levels, while the values from infected quarters were significantly higher. Significant differences between healthy and infected animals were also observed for milk NAG, lactoglobulin and albumin. These data suggest that udder immune response could be influenced both by the cow immune status and by external factors such as pathogens and management. Therefore, the reduction in immune defences, particularly in heifers, is not unavoidable and methods to boost PMN activity should be explored.  相似文献