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61.
Luigi Bardelli Giacomo Poggi 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2006,560(2):517-523
The use of fast digital sampling techniques in Nuclear Physics experiments as a replacement of the standard analog signal processing methods is discussed for applications needing high-resolution signal amplitude measurements. This is for example the case of a solid-state detector with a charge-sensitive preamplifier, processed using fast digital sampling methods. Under very general assumptions, an expression for the achievable resolution and dynamic range of the system is reported, valid for any detector/digitizer/digital-filter combination, taking into account the detector noise and the ADC properties, namely the Effective Number of Bits (ENOB) and the sampling frequency. The system properties are summarized using the parameter PSENOB, i.e. the “Peak-Sensing-Equivalent Number of Bits”. These results can be used to predict the attainable performances in various applications, possibly requiring a resolution/dynamic-range trade-off. Numerical examples for some representative cases in γ-ray spectroscopy and charged particle experiments are reported, demonstrating that the equivalent performances of a 15 bit peak-sensing ADC are feasible with today-available sampling ADCs. For ease of presentation, other non-trivial effects as baseline- and non-linearity-related issues as well as experimental tests of the proposed approach are presented in a companion paper [L. Bardelli, G. Poggi, Digital sampling-systems in high-resolution and wide dynamic-range energy measurements: finite time window, baseline effects, and experimental tests, this issue]. 相似文献
62.
An algorithm for the spectrum of the rotational component of surface ground motion during earthquake is derived. To obtain the rotation the total motion is decomposed into the wave components. Then the rotational motion is obtained in terms of the horizontal and vertical components treated as non-stationary random processes. The evolutionary spectrum of the rotational acceleration is a function of respective translational spectra, their co-spectrum and respective wave parameters. The analysis shows a shift of the higher frequency components in the rotational spectrum. The rotation is a function of the time derivative of translational components. 相似文献
63.
Francesco Salvo Maria Marcella Tripodo Giacomo Dugo 《Journal of the science of food and agriculture》1984,35(2):212-214
High performance liquid chromatography (h.p.l.c.) was used to characterise and quantify fructose and glucose in seven members of the Cucurbitaceae family. The h.p.l.c. system consisted of a μ-Bondapak/Carbohydrate packed column, a solvent system of acetonitrile-water (800 ml l?-1) with a flow rate of 2.5 ml min?-1, and a refractive index detector. The analysis, including sample preparation, was completed in less than 45 min. The quantities of fructose and glucose obtained were, except for one sample, <1% on a fresh weight basis, and the glucose: fructose ratios ranged from 0.41:1 to 0.93:1. 相似文献
64.
The differential forms of heat and work, owing to their dependence upon parameters characterizing the interaction between system and environment (and not only upon the state functions of the system), differ basically from the usual non-exact differentials.
The main aim of this paper is to examine these differences considering quasi-static irreversible processes with the uniformity of internal temperature and pressure. Besides, the specific heat is defined referring only to the properties of the system and to the path of the process and not to the actual heat transfer 相似文献
The main aim of this paper is to examine these differences considering quasi-static irreversible processes with the uniformity of internal temperature and pressure. Besides, the specific heat is defined referring only to the properties of the system and to the path of the process and not to the actual heat transfer 相似文献
65.
Claudia Stefanutti Fabio Mazza Antonio Vivenzio Serafina Di Giacomo Giuseppina Perrone Mariarosaria Serra Antonello Bucci 《Lipids》2009,44(12):1141-1148
An open-labeled randomized trial with parallel groups was carried out to study the effects of Dif1stat® (Monascus purpureus–Linear aliphatic alcohols–Niacin) in the treatment of primary moderate hypercholesterolemia. The trial lasted 8 months. The patients, males and females, were assigned to two groups: A (#130), treated with diet, and B (#110) submitted to diet + Dif1stat®. After 4 months, group A did not show significant changes in Total cholesterol (TC), LDL-cholesterol (LDLC), HDL-cholesterol (HDLC) or non-HDL-cholesterol (non-HDLC). The same group, showed a reduction in TC (–22%), LDLC (–30%) and non-HDLC (–27%) after 8 months (P ≤ 0.001). After 4 months, TC (–21.3%), LDLC (–29%), and non-HDLC (–26%) were significantly lowered in group B (P ≤ 0.001). In group B, TC, LDLC and non-HDLC showed a further reduction after 8 months: –29.4, –38 and –37%, respectively (P ≤ 0.001). Even triglycerides (TG) decreased significantly (–33%) (P ≤ 0.001). After 8 months, group B showed a significant reduction of TG (–33%) (P ≤ 0.001), when compared to group A. Some safety parameters were significantly reduced in both groups: AST and γ-GT in group A after 4 and 8 months, as well as ALT, AST and γ-GT in group B after 8 months (P ≤ 0.001). Dif1stat®, given with a suitable diet, was well tolerated in the long-term and induced an anti-atherogenic plasma lipid and lipoprotein profile, in patients with moderate hypercholesterolemia. 相似文献
66.
It is well known that halons are ozone-depleting substances and their release into the atmosphere has contributed in the last
decades to the reduction in the ozone layer. In consequence to the Montreal Protocol, an international agreement designed
to gradually eliminate the use of such substances, fire protection industry researchers faced the challenge of finding effective
solutions to replace halon extinguishers. This research aims to provide a method to support the decision maker in the selection
of the most suitable extinguisher substance for a specific application. According to such framework, a set of quantitative
and qualitative criteria has been established in the decision-making problem. Such criteria have been properly regrouped in
clusters in order to better evaluate their relative importance by means of AHP method and the criteria have been used for
scoring the alternatives. The choice of an extinguisher substance rather than another has been subsequently carried out by
means of a fuzzy TOPSIS approach, which reflects the vagueness of qualitative criteria. 相似文献
67.
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69.
This paper presents the investigation of the chlorophyll and carotenoid pigments composition in monovarietal virgin olive oils produced from the five main olive varieties (Minuta, Ottobratica, Calabrese, Ogliarola, Baddarica) cultivated in Sicily (southern Italy), from four main olive varieties (DolceAgogia, Moraiolo, Leccino, Frantoio) cultivated in Umbria (central Italy), and from three main olive varieties (Leccino, Oliva Nera di Collecorto, Noccioluta) cultivated in Molise (central Italy). Reversed-phase high performance liquid chromatography using a C-30 column with photodiode array detection was used for pigments analyses. In all, 19 compounds were identified and quantified in 60 olive oils samples. The qualitative pigments pattern was similar among the varieties investigated, whereas quantitative differences were found among the different cultivars; among the varieties investigated in this work, the oils from Umbria showed the highest pigment content (34.19 ppm in average), followed by the oils from Molise (18.61 ppm in average) and the oils from Sicily which showed the lowest pigment contents (13.38 ppm in average). In general, pheophytin a was the major component (range 0.49–19.42 ppm), followed by β-carotene (range 1.27–9.30 ppm) and lutein (range 0.44–5.12 ppm). Those differences may be due to genetic factors and/or geographical differences. Moreover, auroxanthin was detected for the first time in olive oils and was detected only in olive oils from Umbria and Molise regions. The ratio between the two isochromic pigment fractions, namely the ratio between the chlorophyll and carotenoid fractions showed an average value close to unity. The lutein/β-carotene ratio was less than one in the majority of the cases. These parameters, along with other analytical parameters, could be used as indicators of typicality in olive oils. The presence of a specific pigment profile in olive oils could infact be used to guarantee the genuineness of the product, since the quality control of food requires a precise knowledge of the pigments composition of the original products. 相似文献
70.
Naghia Ahmed Dario Ronchi Giacomo Pietro Comi 《International journal of molecular sciences》2015,16(8):18054-18076
Replication and maintenance of mtDNA entirely relies on a set of proteins encoded by the nuclear genome, which include members of the core replicative machinery, proteins involved in the homeostasis of mitochondrial dNTPs pools or deputed to the control of mitochondrial dynamics and morphology. Mutations in their coding genes have been observed in familial and sporadic forms of pediatric and adult-onset clinical phenotypes featuring mtDNA instability. The list of defects involved in these disorders has recently expanded, including mutations in the exo-/endo-nuclease flap-processing proteins MGME1 and DNA2, supporting the notion that an enzymatic DNA repair system actively takes place in mitochondria. The results obtained in the last few years acknowledge the contribution of next-generation sequencing methods in the identification of new disease loci in small groups of patients and even single probands. Although heterogeneous, these genes can be conveniently classified according to the pathway to which they belong. The definition of the molecular and biochemical features of these pathways might be helpful for fundamental knowledge of these disorders, to accelerate genetic diagnosis of patients and the development of rational therapies. In this review, we discuss the molecular findings disclosed in adult patients with muscle pathology hallmarked by mtDNA instability. 相似文献