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Vigentini Ileana Grassi Silvia Sinelli Nicoletta Di Egidio Valentina Picozzi Claudia Foschino Roberto Casiraghi Ernestina 《农业科学与技术》2014,(6):475-486
The aim of this work was to verify the potential of infrared (IR) spectroscopy in near and mid regions to detect the beginning of the malolactic fermentation (MLF) occurring in a model-wine and the further cells autolysis. MLF in wine is a secondary biotransformation due to lactic acid bacteria that usually occurs spontaneou,;ly or after starter inoculation at the end of alcoholic fermentation. Nowadays, it is desirable to supply winemakers with a new rapid and non-destructive approach to monitor MLF progress and 1R spectroscopy technology appears to be suitable for this purpose. The transformation of L-malic acid into L-lactic acid was carried out by inoculating a synthetic wine with an Oenococcus oeni culture and it was monitored through microbiological and chemical methods. At the same time, Fourier transform near infrared (FT-NIR) spectral data, in diffusive transflection mode using an optic probe, and FT-IR spectra, using an germanium crystal attenuated total reflectance (ATR) cell, were collected. Principal component analysis of the spectra was able to identify absorption bands related to the key molecular modifications that took place during the L-malic acid transformation. Thus, the samples were discriminated according to the fermentation phase. Although this study is a preliminary approach, results confirm that near infrared (NIR) and mid infrared (MIR) spectroscopy could be successfully applied to detect the start of MLF and the autolysis of the lactic acid bacteria (LAB) cells. 相似文献
13.
Use of decision support systems (DSS) has thus far been framed as a social process of adoption or technical process of usability. We analyze the development of a DSS as a process of institutionalization of new as well as drift of existing practices. We write an Actor-Network-Theory (ANT) account, i.e. an interpretive study, that follows the traces left by both human and non-human actors (e.g. technology, methodologies, etc.) to understand how a DSS development project institutionalizes DSS technology in several forest management organizations in the German state of Rheinland Pfalz. The research has an innovative value since it uses ANT in the design of a DSS, hence affecting it, while commonly ANT has been used to understand why networks work or do not. Moreover, we use a new technology (PREZITM, www.prezi.com) for the visualization of the whole actor network coherent to the ANT methodology, i.e. “keeping the social flat.” As a result, the development of the ANT account proposed in the present paper, even if still partial, supports the design of new technologies being introduced in current practice and generates an important learning effect thanks to the underpinning interpretative approach. 相似文献
14.
Angioni A Barra A Russo MT Coroneo V Dessi S Cabras P 《Journal of agricultural and food chemistry》2003,51(10):3073-3078
The composition of the essential oil from ripe and unripe berries and leaves of Juniperus oxycedrus L. ssp. oxycedrus, Juniperus phoenicea ssp. turbinata and Juniperus communis ssp. communis was analyzed by GC-MS, and microbiological assays were carried out. Samples were collected in different localities (Sardinia, Italy) and hydro distilled. The yields ranged between 2.54% +/- 0.21 (v\w dried weight) and 0.04% +/- 0.00. A total of 36 components were identified. The major compounds in the essential oils were alpha-pinene, beta-pinene, delta-3-carene, sabinene, myrcene, beta-phellandrene, limonene, and D-germacrene. Both qualitative and quantitative differences between species and between different parts of the plant were observed. The essential oils and their major compounds were tested against Candida albicans, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, and the minimum inhibitory concentration and minimum bactericidal concentration were determined. The results obtained led to a nonsignificant inhibitory effect, although all the essential oils from Juniperus phoenicea ssp. turbinata and the essential oil from leaves of Juniperus oxycedrus ssp. oxycedrus exhibited rather good or weak activity against Candida albicans and Staphylococcus aureus. 相似文献
15.
The possibility of arbitrarily "adding" and "subtracting" single photons to and from a light field may give access to a complete engineering of quantum states and to fundamental quantum phenomena. We experimentally implemented simple alternated sequences of photon creation and annihilation on a thermal field and used quantum tomography to verify the peculiar character of the resulting light states. In particular, as the final states depend on the order in which the two actions are performed, we directly observed the noncommutativity of the creation and annihilation operators, one of the cardinal concepts of quantum mechanics, at the basis of the quantum behavior of light. These results represent a step toward the full quantum control of a field and may provide new resources for quantum information protocols. 相似文献
16.
A new test method for the evaluation of total antioxidant activity of herbal products 总被引:2,自引:0,他引:2
Zaporozhets OA Krushynska OA Lipkovska NA Barvinchenko VN 《Journal of agricultural and food chemistry》2004,52(1):21-25
A new test method for measuring the antioxidant power of herbal products, based on solid-phase spectrophotometry using tetrabenzo-[b,f,j,n][1,5,9,13]-tetraazacyclohexadecine-Cu(II) complex immobilized on silica gel, is proposed. The absorbance of the modified sorbent (lambda(max) = 712 nm) increases proportionally to the total antioxidant activity of the sample solution. The method represents an attractive alternative to the mostly used radical scavenging capacity assays, because they generally require complex long-lasting stages to be carried out. The proposed test method is simple ("drop and measure" procedure is applied), rapid (10 min/sample), requires only the monitoring of time and absorbance, and provides good statistical parameters (s(r)相似文献
17.
M A Memon J J McClure E A Usenik 《Journal of the American Veterinary Medical Association》1987,191(5):563-564
An 8-year-old Quarter Horse stallion was admitted with a swelling involving the prepuce, dorsal part of the scrotum, and root of the penis. The swelling was first noticed 10 days after breeding, with no evidence that it had resulted from a kick by the mare. The penis was retracted into the prepuce, except for a 10- to 15-cm protrusion of the glans penis. Treatment included warm hydrotherapy, massage, stockinette compression, antidiuretics, antibiotics, penile support, and exercise, without success. At necropsy, a massive preputial hematoma was found extending forward from the root of the penis to 12 cm proximal to the glans penis. The exact origin of the hematoma could not be determined. Most likely, bleeding had originated from the vascular plexus lying subfascially on the surface of the penis outside the intact tunica albuginea or from a branch of the external pudendal artery. 相似文献
18.
Rodriguez-Rodriguez R Perona JS Herrera MD Ruiz-Gutierrez V 《Journal of agricultural and food chemistry》2006,54(6):2096-2102
There is currently a considerable amount of interest in the benefits of certain dietary elements, and in particular of olive oil, in endothelial function and thus in hypertension. "Orujo" or pomace olive oil is obtained from the residues of the olive by a novel centrifugation process, and it is a good dietary source of triterpenic compounds such as oleanolic and maslinic acid, erythrodiol, and uvaol. Until now, there was no information available regarding the properties of these triterpenoids on the vasculature of hypertensive animals. However, in this in vitro study, we have analyzed the vasorelaxation induced by these triterpenoids in isolated aorta from spontaneously hypertensive rats (SHR). The triterpenoids tested induced concentration-dependent vasorelaxation, mostly involving nitric oxide (NO). Indeed, the responses were attenuated by removal of the endothelium or following pretreatment with the NO synthase inhibitor L-NAME. Furthermore, the differences that were observed in the potency of relaxation, the selectivity, and the dependence on the endothelium were attributed to structural features of the triterpenoids. In conclusion, triterpenic components in pomace olive oil induce vasorelaxation of the aorta from SHR, and this effect generally involves endothelial NO. 相似文献
19.
Simona Normando VMD Elisabetta Canali Prof Valentina Ferrante VMD PhD Marina Verga Prof. 《Journal of Equine Veterinary Science》2002,22(3)
A survey was carried out in 25 riding centers to evaluate the prevalence of behavioral problems among saddle horses and to investigate the relationship between these and individual traits, training and management of the affected horses. Seven percent of the 650 horses examined had some kind of behavioral problems, and crib-biting was the most frequent. These behavioral problems seemed to be related to the sort of training and management. Show jumping horses tended to be affected simultaneously by more than one behavioral problem and to be more aggressive towards other horses. Although show jumpers were ridden more often, they had fewer opportunities to graze. The prevalence of behavioral problems was lower among those horses ridden Western style than among those ridden English style; the latter employs more hand to bit contact. The study also showed that horses groomed and ridden by one and the same person had more problems than horses groomed and ridden also by different people. 相似文献
20.
Valentina Vitale Rita Balocchi Maurizio Varanini Micaela Sgorbini Alberto Macerata Claudio Sighieri Paolo Baragli 《Journal of Veterinary Behavior: Clinical Applications and Research》2013,8(5):400-403
Analysis of heart rate variability (HRV) is a noninvasive approach for investigating the sympathovagal balance of the autonomic nervous system. In recent years, HRV has been increasingly evaluated in animal research. In horses, it has been suggested that basal resting conditions can be achieved by restraining them. The aim of this study was to verify how restriction of movement influences HRV i2n horses. Ten healthy standardbred mares were used to measure the electrocardiographic signal under 2 conditions: free to move in the stall and restrained in the stock. Results indicate that the restriction of movement is associated with increased nervous system sympathetic activity not consistent with resting conditions. 相似文献