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71.
Vasta V Ventura V Luciano G Andronico V Pagano RI Scerra M Biondi L Avondo M Priolo A 《Meat science》2012,90(2):451-456
This study was designed to assess whether different grazing managements affect the appearance of organic volatile compounds (VOC) in lamb fat. Forty-two lambs were divided into four groups: 9 lambs were restricted in stall and fed concentrate (S group); 12 lambs grazed from 9 am to 5 pm (8 h group); 10 lambs grazed from 9 am to 1 pm (4hAM group) and 11 lambs grazed from 1 pm to 5 pm (4hPM group). After 72 days on feed the animals were slaughtered and the perirenal fat subjected to SPME-GC/MS analysis of VOC; the data were analyzed by stepwise discriminant analysis. The 6-methyl-2-heptanone and furanone, 2,5-dimethyl, 4-hydroxy-3(2H) allowed discrimination between the 4hAM and the 4hPM animals. These are the first results indicating that the time of the day in which the animals are allowed to graze affects the appearance of VOC in lamb fat. 相似文献
72.
Avondo M Bonanno A Pagano RI Valenti B Grigoli AD Luigia Alicata M Galofaro V Pennisi P 《The Journal of dairy research》2008,75(1):48-54
We evaluated the effect of grazing time of day on goat milk chemical composition, renneting properties and milk fatty acid profile in a Mediterranean grazing system. Sixteen lactating Girgentana goats were divided into two experimental groups and housed in individual pens, where they received 500 g/d of barley grain. For 5 weeks the two groups were left to graze in two fenced plots on a ryegrass sward as follows: morning group (AM), from 9.00 to 13.00; afternoon group (PM), from 12.00 to 16.00. In selected herbage, water-soluble carbohydrates (WSC) increased in the afternoon (204 v. 174 g/kg dry matter, DM; P=0.01), whereas crude protein (CP) and linolenic acid decreased (respectively, 16.7 v. 19.8% DM; P<0.01 and 26.8 v. 30.4 g/kg DM; P<0.01). Pasture dry matter intake (DMI) was significantly higher in the afternoon (0.82 v. 0.75 kg/d; P=0.026). Fat corrected milk production (FCM), milk fat and lactose content were not affected by treatment, whereas protein and titrable acidity ( degrees SH) increased in the PM group (respectively 3.56 v. 3.42%; P=0.01; 3.55 v. 3.22 degrees SH/50 ml; P=0.01). In contrast, milk urea content was significantly higher in the AM group (381 v. 358 mg/l; P=0.037). The results seem to indicate that an improvement in ruminal efficiency might be obtained by shifting grazing time from morning to afternoon, as a consequence of a more balanced ratio between nitrogenous compounds and sugars. Indeed, the higher linolenic acid and the lower conjugated linoleic acid (CLA) (respectively 1.02 v. 0.90, P=0.037; 0.71 v. 0.81% of total fatty acids, P=0.022) in the milk of goats grazing in the afternoon seem to indicate a reduced biohydrogenation activity in the PM group. 相似文献
73.
Divya Bharat Rafaela Ramos Mororo Cavalcanti Chrissa Petersen Nathan Begaye Brett Ronald Cutler Marcella Melo Assis Costa Renata Kelly Luna Gomes Ramos Marina Ramos Ferreira Youyou Li Leena P. Bharath Emma Toolson Paul Sebahar Ryan E. Looper Thunder Jalili Namakkal S. Rajasekaran Zhenquan Jia J. David Symons Pon Velayutham Anandh Babu 《Molecular nutrition & food research》2018,62(2)
74.
Andreia Maria da Anunciao Gomes Marcelo Manzi Marinho Marcella Coelho Berjante Mesquita Ana Carolina Coelho Prestes Miquel Lürling Sandra M. F. O. Azevedo 《Lakes & Reservoirs: Research and Management》2020,25(3):275-282
Both global warming and eutrophication are predicted to promote cyanobacterial blooms. At the same time, how tropical phytoplankton communities exhibiting different trophic state systems will respond to temperature variations is less clear. To investigate the effects of temperature changes and nutrient additions on phytoplankton communities, and gain insights regarding possible resistance to these effects, the present study focused on testing the hypothesis that temperature variations and nutrient additions will have a stronger effect on cyanobacteria dominance in eutrophic water system than in oligo‐mesotrophic water systems. Experiments were conducted with phytoplankton communities from two aquatic ecosystems exhibiting different trophic states. To this end, water samples from a eutrophic and oligo‐mesotrophic system were collected and incubated at 25 and 30ºC. Samples receiving additional surplus nitrogen (N) and phosphorus (P) inputs were included to serve as eutrophication treatments. The study results indicated that temperature variations alone did not promote cyanobacteria in water from either the oligo‐mesotrophic or eutrophic water system. However, nutrient enrichment of the water from the eutrophic system significantly boosted the cyanobacteria, with the biomass increasing by factor of 10 for both the 25°C and 30°C treatments. In contrast, eutrophication of the water from the oligo‐mesotrophic system did not change the relative contribution of phytoplankton groups, with the response ratios being much lower than those for the water from the eutrophic system. Although based on a simple experimental design, the results of the present study suggest that cyanobacteria dominance is favoured by further nutrient additions for eutrophic water systems, independently of any direct temperature effects, and that more pristine environments possess some resistance against eutrophication effects. Since global warming is assumed to indirectly intensify eutrophication symptoms, the results of the present study underscore the importance of nutrient control. 相似文献
75.
Cascianelli Silvia Cornia Marcella Baraldi Lorenzo Cucchiara Rita 《International Journal on Document Analysis and Recognition》2022,25(3):207-217
International Journal on Document Analysis and Recognition (IJDAR) - Handwritten Text Recognition (HTR) in free-layout pages is a challenging image understanding task that can provide a relevant... 相似文献
76.
Inhibition of para‐Hydroxyphenylpyruvate Dioxygenase by Analogues of the Herbicide Nitisinone As a Strategy to Decrease Homogentisic Acid Levels,the Causative Agent of Alkaptonuria 下载免费PDF全文
Dr. Marcella Laschi Dr. Giulia Bernardini Dr. Elena Dreassi Dr. Lia Millucci Dr. Michela Geminiani Dr. Daniela Braconi Dr. Barbara Marzocchi Prof. Maurizio Botta Prof. Fabrizio Manetti Prof. Dr. Annalisa Santucci 《ChemMedChem》2016,11(7):674-678
Alkaptonuria (AKU) is a rare multisystem metabolic disease caused by deficient activity of homogentisate 1,2‐dioxygenase (HGD), which leads to the accumulation of homogentisic acid (HGA). Currently, there is no treatment for AKU. The sole drug with some beneficial effects is the herbicide nitisinone ( 1 ), an inhibitor of p‐hydroxyphenylpyruvate dioxygenase (4‐HPPD). 1 has been used as a life‐saving drug in infants with type I tyrosinemia despite severe side effects due to the buildup of tyrosine. Four clinical trials of nitisinone to treat AKU have shown that 1 consistently decreases HGA levels, but also caused the accumulation of tyrosine in blood serum. Moreover, the human preclinical toxicological data for 1 are incomplete. In this work, we performed pharmacodynamics and toxicological evaluations of 1 , providing the first report of LD50 values in human cells. Intracellular tyrosinemia was also evaluated. Three additional 4‐HPPD inhibitors with a more favorable profile than that of 1 in terms of IC50, LD50, and tyrosine accumulation were also identified among commercially available compounds. These may be promising starting points for the development of new therapeutic strategies for the treatment of AKU. 相似文献
77.
78.
Wojciech Mróz Karol Falkowski Maciej Miśnik Ester Rossi Marcella Balordi Waldemar Stampor 《Organic Electronics》2013,14(11):2880-2888
Electric field-modulated photoluminescence (EML) measurements are presented for vacuum-evaporated films of cyclometallated Pt (II) complexes of 1,3-di(2-pyridyl) benzenes used as triplet emitters in organic light-emitting diodes (OLEDs). The excimer phosphorescence is quenched by the external electric field of 2.5 MV/cm up to 25% but the same effect on monomer phosphorescence is one order of magnitude smaller. The higher quenching effect for triplet excimers than triplet monomers in solid films of Pt complexes is rationalized assuming excimers to be populated within excimer-active domains of the films through an intermediate stage of geminate (e–h) pairs derived from dissociated monomer excitons. The EML data for excimers are successfully described in the framework of Sano–Tachiya–Noolandi–Hong (STNH) theory of geminate (e–h) pair recombination where the final recombination step (e–h capture) proceeds on a sphere of finite radius (a) with a finite speed. The conventional Onsager theory (a = 0) is sufficient to explain the EML quenching effect for monomers. The results are important for explaining the decrease of electroluminescence quantum efficiency observed in OLEDs working under high electric fields. 相似文献
79.
Gyeong-Man Kim Kim Huyen Trang Le Sara Maria Giannitelli Yu Jin Lee Alberto Rainer Marcella Trombetta 《Journal of materials science. Materials in medicine》2013,24(6):1425-1442
Currently, one of the main drawbacks of using poly(ε-caprolactone) in the biomedical and pharmaceutical fields is represented by its low biodegradation rate. To overcome this limitation, electrospinning of PCL blended with a water-soluble poly(N-vinyl-2-pyrrolidone) was used to fabricate scaffolds with tunable fiber surface morphology and controllable degradation rates. Electrospun scaffolds revealed a highly immiscible blend state. The incorporated PVP phase was dispersed as inclusions within the electrospun fibers, and then easily extracted by immersing them in cell culture medium, exhibiting nanoporosity on the fiber surface. As a striking result, nanoporosity facilitated not only fiber biodegradation rates, but also improved cell attachment and spreading on the blend electrospun scaffolds. The present findings demonstrate that simultaneous electrospinning technique for PCL with water-soluble PVP provides important insights for successful tuning biodegradation rate for the PCL electrospun scaffolds but not limited to expand other high valuable biocompatible polymers for the future biomedical applications, ranging from tissue regeneration to controlled drug delivery. 相似文献
80.
Marcella MastromatteoLucia Lecce Nicoletta De VietroPietro Favia Matteo Alessandro Del Nobile 《Journal of food engineering》2011,104(3):373-379
In this study, polyvinyl alcohol films incorporated with lysozyme, as active compound, and natural fibres were investigated. Various composite systems were developed to control the release of lysozyme from the matrix by using different surface treatments of the natural fibres. Specifically, the plasma enhanced-chemical vapour deposition of acrylic acid and diamond-like coating on spelt bran powders, in a particular home-made rotating plasma reactor, were studied. Moreover, a mathematical model able to describe the release kinetics of the active compound from the polyvinyl alcohol film into water was presented. To validate the model the release kinetic of lysozyme were determined. The model was successfully used to fit the above experimental data, corroborating the validity of the hypothesis made to derive it. Results showed that the incorporation of treated natural fibres to the polymeric matrix allows to obtaining a decrease of the lysozyme diffusion coefficient up to 73.5% compared to active film without fibre. 相似文献