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91.
A full-length cDNA, encoding a Bowman-Birk protease inhibitor (BBI), was isolated from lentil immature seeds. The deduced amino acid sequence was longer than that of the BBI extracted from lentil seeds and contained two binding sites; the first inhibitory site inhibits trypsin whereas the second one inhibits chymotrypsin. In order to characterize this lentil BBI, a longer (complete) and its C-terminally processed (mature) form were heterologously expressed in the yeast Pichia pastoris. The recombinant BBI proteins proved to be active against trypsin and chymotrypsin, showing Ki values at nanomolar levels. Mass spectrometry analysis revealed that complete BBI was composed of an array of molecular masses, whereas mature BBI showed the presence of a major peak of the expected size. The effects of mature BBI on the growth of human colon adenocarcinoma HT29 and colonic fibroblast CCD-18Co cells were evaluated. Lentil BBI was able to inhibit the growth of such cells at concentrations higher than 19 μM, in a concentration-dependent manner; by contrast, the CCD18-Co cells were unaffected. These data broaden our knowledge of the beneficial biological activities of naturally-occurring BBI proteins and address the need for systematic evaluation of natural variants in order to design novel strategies in preventive medicine.  相似文献   
92.
Sixty male Apenninica suckling lambs carcasses were studied in order to evaluate the relationship between carcass and meat quality of light lambs as evaluated according to the EU Mediterranean classification system. Increased carcass weight (6–12 kg) was accompanied by greater carcass size and compactness and reduced bone percentage. Moreover the meat quality was similar with the increase of carcass weight in terms of colour, water holding capacity and suitability for domestic storage. No differences for the examined parameters were found between carcasses classified in quality 1 and 2. The EU Mediterranean classification system appears to be unrelated to the quality of the merchandized meat.  相似文献   
93.
Acute toxicity bioassays in which fish were exposed to short-term cyclic fluctuations of ammonia were conducted on rainbow trout (Salmo gairdneri) and on cutthroat trout (S. clarki). Companion tests were also conducted in which test fish were subjected to ammonia at constant concentrations. The tests ranged in duration from 96 h to 4 weeks. Median lethal concentration (LC 50) values in terms of both average and peak concentrations of ammonia for the fluctuating concentration tests were compared with LC 50 values for the constant concentration (conventional) tests. Based on comparisons of total dose exposure, results showed that fish were more tolerant of constant concentrations of ammonia than of fluctuating concentrations. Fish subjected to fluctuating concentrations of ammonia at levels below those acutely toxic were subsequently better able to withstand exposure to higher fluctuating concentrations than fish not previously so acclimated.  相似文献   
94.
A research program addressed to evaluate the magnesium hydride storage scaling up effects is being developed by CESI RICERCA, Milano, and the Hydrogen Group of Padova University. A storage device containing 500 g of magnesium hydride powder (manufactured by Venezia Tecnologie S.p.A. using high-energy ball milling) has been designed and tested in different operating conditions. A number of absorption and desorption cycles at different temperatures and pressures has been carried out in order to see if the results are comparable with laboratory data obtained on small amounts (fractions of grams) of powder samples. A sensible performance degradation that reduced the overall storage capacity of about 50% has been noticed after 20 cycles, presumably due to local powder heating, fragmentation and subsequent compaction. Further tests on a smaller tank equipped also with a porous baffle gave useful indications for the design of an improved large hydrogen reservoir.  相似文献   
95.
The scope for diffusion of very low-enthalpy geothermal plants in the Piemonte region of Italy, using groundwater heat pumps (GWHP), was analyzed to check environmental sustainability and the benefits in terms of reducing greenhouse gas emissions from fossil fuels. GWHP implementation seemed particularly suitable to the specific characteristics of the Piemonte plain. An important thick and productive shallow aquifer is present across the entire plain beneath the major energy users and is therefore appropriate for geothermal energy development purposes. The building stock could be adapted to heat pumps in different ways, but objective-oriented policies will be required to reach the best results in terms of environmental benefits.  相似文献   
96.
An integrated approach to quality of service for content delivery using Web services includes quality definitions, user contracts, and fault monitoring.  相似文献   
97.
Summary An investigation of the distribution of the cyclic oligomers of poly(lactic acid), formed both by pyrolysis of the polymer and by equilibration with a catalyst, has been performed by Negative Chemical Ionization and Thermospray Mass Spectrometry.The results indicate that the two methods can be used to obtain information on the relative amounts of the oligomers present in the mixture.  相似文献   
98.
A simple method for parametric analysis of grid amplifier performances is presented here. The proposed approach is based on the development of an equivalent transmission line model where each element of the grid is represented by an S-matrix derived from a full-wave simulation in an infinite array environment. The proposed technique makes it possible to investigate the dependency of grid amplifier performance on its major parameters taking into account the actual geometry of each part of the circuit while preserving the simulation efficiency.  相似文献   
99.
A trustable and accurate ground truth is a key requirement for benchmarking self-localization and mapping algorithms; on the other hand, collection of ground truth is a complex and daunting task, and its validation is a challenging issue. In this paper we propose two techniques for indoor ground truth collection, developed in the framework of the European project Rawseeds, which are mutually independent and also independent on the sensors onboard the robot. These techniques are based, respectively, on a network of fixed cameras, and on a network of fixed laser scanners. We show how these systems are implemented and deployed, and, most importantly, we evaluate their performance; moreover, we investigate the possible fusion of their outputs.  相似文献   
100.
The problem of information flow in multithreaded programs remains an important open challenge. Existing approaches to specifying and enforcing information-flow security often suffer from over-restrictiveness, relying on nonstandard semantics, lack of compositionality, inability to handle dynamic threads, inability to handle synchronization, scheduler dependence, and efficiency overhead for the code that results from security-enforcing transformations. This paper suggests a remedy for some of these shortcomings by developing a novel treatment of the interaction between threads and the scheduler. As a result, we present a permissive noninterference-like security specification and a compositional security type system that provably enforces this specification. The type system guarantees security for a wide class of schedulers and provides a flexible and efficiency-friendly treatment of dynamic threads.  相似文献   
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