A microwave tomographic system for wood characterization in the forest products industry     

Matteo Pastorino  Alessandro Fedeli  Andrea Salvadè  Samuel Poretti  Manuela Maffongelli 《Wood material science & engineering》2015,10(1):75-85

Abstract

Nondestructive testing and evaluation techniques able to extract information about the internal structure of the samples under test are very important in the wood industry. Microwave imaging systems have been considered for a long time promising apparatuses for this task. In this framework, approaches exploiting the full scattering phenomena for creating images of the distributions of the dielectric properties of the targets have been developed in the last few years. In this paper, a prototype of microwave tomographic system is presented and several experimental validation confirming its suitability for the use in the wood and forest product industry are reported.  相似文献   

Determination of cocoa butter equivalents in milk chocolate by triacylglycerol profiling     

Buchgraber M  Androni S  Anklam E 《Journal of agricultural and food chemistry》2007,55(9):3284-3291

An analytical approach for the detection and quantification of cocoa butter equivalents (CBEs) in milk chocolate is presented. It is based on (i) a comprehensive standardized database covering the triacylglycerol composition of a wide range of authentic milk fat (n=310), cocoa butter (n=75), and CBE (n=74) samples and 947 gravimetrically prepared mixtures thereof, (ii) the availability of a certified cocoa butter reference material (IRMM-801) for calibration, (iii) an evaluation algorithm, which allows a reliable quantification of the milk fat content in chocolate fats using a simple linear regression model, (iv) a subsequent correction of triacylglycerols deriving from milk fat, (v) mathematical expressions to detect the presence of CBEs in milk chocolate, and (vi) a multivariate statistical formula to quantify the amount of CBEs in milk chocolate. The detection limit was 1% CBE in chocolate fat (0.3% CBE in milk chocolate, having a fat content of 30%). For quantification, the average error for prediction was 1.2% CBE in chocolate fat, corresponding to 0.4% in milk chocolate (fat content, 30%).  相似文献   

Anthocyanins present in selected tropical fruits: acerola, jambolão, jussara, and guajiru     

de Brito ES  de Araújo MC  Alves RE  Carkeet C  Clevidence BA  Novotny JA 《Journal of agricultural and food chemistry》2007,55(23):9389-9394

Many tropical fruits are rich in anthocyanins, though limited information is available about the characterization and quantification of these anthocyanins. The identification and quantification of anthocyanin pigments in four tropical fruits were determined by HPLC-MS/MS. Fruits studied included acerola (Malphigia emarginata), jussara (Euterpe edulis), jambol?o (Syzygium cumini), and guajiru (Chrysobalanus icaco). All four fruits were found to contain anthocyanin pigments. Anthocyanidin backbones included cyanidin, delphinidin, peonidin, pelargonidin, petunidin, and malvidin. Guajiru contained several acylated forms, while acerola, jussara, and jambol?o contained only nonacylated glycosides. These results demonstrate that these tropical fruits are rich in anthocyanins and that the anthocyanins are widely ranging in anthocyanidin backbone, glycosylation, and acylation.  相似文献   

Prevalence of antimicrobial resistance in enteric Escherichia coli from domestic pets and assessment of associated risk markers using a generalized linear mixed model     

Liliana R. Leite-Martins  Maria I.M. Mahú  Ana L. Costa  Ângelo Mendes  Elisabete Lopes  Denisa M.V. Mendonça  João J.R. Niza-Ribeiro  Augusto J.F. de Matos  Paulo Martins da Costa 《Preventive veterinary medicine》2014

Antimicrobial resistance (AMR) is a growing global public health problem, which is caused by the use of antimicrobials in both human and animal medical practice. The objectives of the present cross-sectional study were as follows: (1) to determine the prevalence of resistance in Escherichia coli isolated from the feces of pets from the Porto region of Portugal against 19 antimicrobial agents and (2) to assess the individual, clinical and environmental characteristics associated with each pet as risk markers for the AMR of the E. coli isolates.  相似文献   

Assessment of the combination of spinosad and milbemycin oxime in preventing the development of canine Angiostrongylus vasorum infections     

Claudia Böhm  Manuela Schnyder  Stig Milan Thamsborg  Caryn M. Thompson  Candace Trout  Sonja Wolken  Beate Schnitzler 《Veterinary parasitology》2014,199(3-4):272-277

Angiostrongylus vasorum is an increasingly reported parasite in Europe that develops in dogs after ingestion of infective third stage larvae (L3) that reside in gastropod molluscs which are needed to complete the parasite's life-cycle. Infection can produce a diversity of clinical signs, determined by involvement of the respiratory, neurological, and/or coagulation system, with a likely fatal outcome in the absence of treatment. Few drugs have been shown to reliably prevent infection, and data on treatment of infections is limited. A controlled, randomized, partially blinded laboratory study was therefore executed to evaluate the efficacy and safety of a combination tablet of spinosad/milbemycin oxime in dogs inoculated with approximately 250 A. vasorum L3. Sixteen healthy nematode free adult dogs were randomly allocated to two study groups of 8 dogs each. Thirty days post inoculation (dpi) all dogs in the fed state were treated: dogs in group B were treated with spinosad and milbemycin oxime at the dose rates of 45–60 mg/kg and 0.75–1.0 mg/kg bodyweight, respectively, approximately the lower half portion of the expected full unit dose range; dogs in group A were treated with placebo tablets. All dogs were euthanized and necropsied 56–58 dpi. The heart and lungs were examined to determine the presence of A. vasorum. All placebo group dogs were infected at necropsy with counts ranging from 22 to 98 adult worms and a geometric mean worm count of 55.2. In contrast, the geometric mean worm count in the spinosad/milbemycin oxime group was 0.7 with worm numbers ranging from 0 to 8. The results of this study demonstrate that a single treatment with the tablet combination of spinosad and milbemycin oxime administered 30 dpi provided 98.8% preventive efficacy against development of adult A. vasorum infections. Monthly treatments with spinosad and milbemycin oxime have the potential to prevent the establishment of infections with A. vasorum in dogs.  相似文献   

Successful analysis of gut contents in fungal-feeding oribatid mites by combining body-surface washing and PCR     

Cecilia Remén  Manuela Krüger 《Soil biology & biochemistry》2010,42(11):1952-1957

The feeding habits of soil mesofauna have been a mystery for decades, and depending on the methods used, different degrees of feeding specialisation have been observed. A new way to study the almost unknown feeding habits of soil mesofauna e.g. oribatid mites is to use PCR-based techniques. When applying PCR on these small organisms, the low amount of ingested DNA can cause problems. Even more important is to certify that the amplified DNA does not originate from body-surface contamination. The aim of this study was to analyse if washing of the body surface combined with PCR can be a successful approach when identifying the food ingested by fungivorous mites. The method was developed in a laboratory system where we used the oribatid mite Archegozetes longisetosus as a model organism due to its relatively short life cycle and ease of laboratory culturing. The results demonstrated that surface contamination is a serious problem. Both washing and dissection was needed to remove surface contamination on such small organisms. To get a reliable result the samples also had to contain at least five pooled guts, but preferably ten. This is the first step towards a successful use of PCR-based methods to study natural feeding habits of species most likely contaminated on the body surface. When modified for field conditions, the results obtained by this method have a high potential to answer many questions about the animals feeding habits, and their functional role in the soil.  相似文献   

Interaction of the mutant genes B,og c,hp and t in the coloring of tomato fruit     

Thiago Matos Andrade  Wilson Roberto Maluf  Celso Mattes de Oliveira  Luiz Antônio Augusto Gomes  Daniela Costa Santos  Regis de Castro Carvalho  Ranoel José de Sousa Gonçalves  Álvaro Carlos Gonçalves Neto 《Euphytica》2015,205(3):773-783

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Carotenoid, chlorophyll, and chlorophyll-derived compounds in grapes and port wines     

Mendes-Pinto MM  Silva Ferreira AC  Caris-Veyrat C  Guedes de Pinho P 《Journal of agricultural and food chemistry》2005,53(26):10034-10041

Carotenoids and chlorophyll-derived compounds in grapes and Port wines were investigated by HPLC-DAD and HPLC-DAD-MS (ESP+) analysis. A total of 13 carotenoid and chlorophyll-derived compounds are formally reported in grapes, 3 are identified for the first time, pheophytins a and b and (13Z)-beta-carotene, and 3 others remain unknown. In Port wines 19 compounds with carotenoid or chlorophyll-like structures are present, 8 still unidentified. The young wines showed higher total carotenoid content and chlorophyll-like compounds compared to aged Ports, with lutein and beta-carotene as major carotenoids. Among samples analyzed of monovarietal Vitis vinifera L. cultivar wines produced with the five most important Douro varieties, Tinta Roriz contained the highest levels of carotenoids and Touriga Franca the lowest. The forced-aging study indicated that lutein was more sensitive to temperature than beta-carotene. Additionally, aged wines showed higher ratios of beta-carotene/lutein concentrations compared to new Ports. Rates of degradation of chlorophyll derivative compounds were higher than those for carotene and lutein.  相似文献   

Purification and partial characterization of lipoxygenase from desert truffle (Terfezia claveryi Chatin) ascocarps     

Pérez-Gilabert M  Sánchez-Felipe I  García-Carmona F 《Journal of agricultural and food chemistry》2005,53(9):3666-3671

A lipoxygenase from Terfezia claveryi Chatin ascocarp, a mycorrhizal hypogeous fungus, is described for the first time. The higher proportion of PUFA in T. claveryi ascocarps makes lipid rancidity the main factor limiting its storage life. Thus, the studies on LOX from T. claveryi are important because this enzyme, among other roles, may be involved in an alteration of lipids leading to consumer rejection. The enzyme has been purified to apparent homogeneity by phase partitioning in the presence of Triton X-114, followed by two steps of cation-exchange chromatography. The purified T. claveryi LOX preparation consisted of a single major band with an apparent molecular mass of 66 kDa after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzymic activity exhibited a strong specificity toward linoleic and linolenic acids as substrates, while only 32% activity was observed using gamma-linolenic acid. The pH optimum of this enzyme was pH 7.0. When the enzyme reacted with linoleic acid, it produced a single peak, which comigrated with standard 13-hydroperoxy-octadecadienoic acid; 13-hydroperoxy-octadecatrienoic acid was produced during the reaction with linolenic acid.  相似文献   

Interaction of contaminated sediment from a salt marsh with estuarine water: evaluation by leaching and ecotoxicity assays and salts from leachate evaporation     

Sara Peres  M. Clara F. Magalhães  Maria Manuela Abreu  Sara Leitão  Ana Santos  Maria José Cerejeira 《Journal of Soils and Sediments》2016,16(5):1612-1624

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