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Theresa Hague Andrea Petroczi Paul LR Andrews James Barker Declan P Naughton 《Chemistry Central journal》2010,4(1):2
This is a correction to the following paper: Hague T, Petroczi A, Andrews PR, Barker J, Naughton DP: Determination of metal
ion content of beverages and estimation of target hazard quotients: a comparative study. Chem Central J 2008, 2:13. 相似文献
3.
The Re-Analysis of the 1700 MeV Structure of the P
11 Partial Wave Using the πN → KΛ Production Data
We have used the Breit-Wigner resonance model with S
11, P
11, and P
13 resonances in the s-channel to reanalyze the old πN → KΛ data with the aim to establish the origin of the prominent structure in the total cross section in the vicinity of 1700 MeV.
We have found a new set of resonance parameters enforcing the experimentally observed structure of the total cross-section
data simultaneously with the linear dependence of the differential cross sections with cos θ in the energy range 1650 MeV
< W < 1800 MeV. Owing to the differential cross-section linearity, the P
13 partial wave has been strongly attenuated in this model, and the total cross-section structure is attributed to the resonant
behavior of the P
11 partial wave. In this paper we show that, at least in the Breit-Wigner resonance model, it is not possible to achieve a detailed
reproduction of the narrow 1700 MeV total cross-section peak using the standard partial widths. To understand the phenomenon,
a much narrower width of a resonant state, the N(1710) P
11 in our case, is required (Γ ≈ 68 MeV), but then the agreement of the model predictions with the total cross-section data
at higher energies is lost. One way out is to allow for the existence of another P
11 resonance in that energy range. The same feature is shown by the polarization data: The introduction of a much narrower resonance
spoils the level of agreement which the Breit-Wigner resonance model is able to achieve with experiment, but the consistency
is restored when another resonance is introduced. Analyzing the qqq or qqqq
nature of the recommended narrow P
11 structure in the neighborhood of 1700 MeV we reopen (remind of) the possibility that another P
11 resonant state exists in addition to the standard N(1710) P
11 PDG-resonance, and that one of the two states can be identified with the yet undiscovered cryptoexotic pentaquark state.
To clarify the situation, we strongly recommend a remeasurement of the πN → KΛ process in the energy range 1650 MeV < W < 1800 MeV. 相似文献
4.
The generation of dressed meson–nucleon scattering-matrix poles is presented. A possible scenario for the interrelation of
bare and dressed baryon poles is shown by using a particular version of coupled-channel Dyson–Schwinger type model. These
findings are then applied to the Roper resonance, and the conclusion is drawn that it is dynamic in nature. A possible correlation
between bare and dressed propagator poles on one side and the quantities of constituent quark-model calculations on the other
side are discussed. 相似文献
5.
Bruno Bassan Claudia Ceci 《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(1-2):55-77
In this paper we show that the solution of a stochastic boundary value problem with additive noise and with a completely nonlinear drift is a Markov field if only if the boundary condition is an initial or a final type condition 相似文献
6.
In this paper we study a nonlinear filtering problem for a general Markovian partially observed system (X,Y), whose dynamics is modeled by correlated jump-diffusions having common jump times. At any time t∈[0,T], the σ-algebra $\mathcal{F}^{Y}_{t}:= \sigma\{ Y_{s}: s\leq t\}$ provides all the available information about the signal X t . The central goal of stochastic filtering is to characterize the filter, π t , which is the conditional distribution of X t , given the observed data $\mathcal{F}^{Y}_{t}$ . In Ceci and Colaneri (Adv. Appl. Probab. 44(3):678–701, 2012) it is proved that π is the unique probability measure-valued process satisfying a nonlinear stochastic equation, the so-called Kushner-Stratonovich equation (in short KS equation). In this paper the aim is to improve the hypotheses to obtain the KS equation and describe the filter π in terms of the unnormalized filter ?, which is solution of a linear stochastic differential equation, the so-called Zakai equation. We prove the equivalence between strong uniqueness of the solution of the KS equation and strong uniqueness of the solution of the Zakai one and, as a consequence, we deduce pathwise uniqueness of the solution of the Zakai equation by applying the Filtered Martingale Problem approach (Kurtz and Ocone in Ann. Probab. 16:80–107, 1988; Ceci and Colaneri in Adv. Appl. Probab. 44(3):678–701, 2012). To conclude, we discuss some particular models. 相似文献
7.
A partially observable control problem for an R
d
-valued jump process with counting observations is studied. The state and the observations may be strongly dependent and, in particular, the two processes may jump together. An equivalent separated problem is introduced and the existence of an optimal control for the separated problem is obtained in the class of relaxed and generalized controls. Equivalence between the initial problem and the relaxed generalized separated control problem is discussed. 相似文献
8.
Theresa Hague Andrea Petroczi Paul LR Andrews James Barker Declan P Naughton 《Chemistry Central journal》2008,2(1):13
Background
Considerable research has been directed towards the roles of metal ions in nutrition with metal ion toxicity attracting particular attention. The aim of this study is to measure the levels of metal ions found in selected beverages (red wine, stout and apple juice) and to determine their potential detrimental effects via calculation of the Target Hazard Quotients (THQ) for 250 mL daily consumption. 相似文献9.
Volpicella M Leoni C Costanza A De Leo F Gallerani R Ceci LR 《Current protein & peptide science》2011,12(5):386-398
Plant protease inhibitors (PIs) are generally small proteins present in high concentrations in storage tissues (tubers and seeds), and to a lower level in leaves. Even if most of them are active against serine and cysteine proteases, PIs active against aspartic proteases and carboxypeptidases have also been identified. Inhibitors of serine proteases are further classifiable in several families on the basis of their structural features. They comprise the families known as Bowman-Birk, Kunitz, Potato I and Potato II, which are the subject of review articles included in this special issue. In the present article we aim to give an overview of other families of plant PIs, active either against serine proteases or other class of proteases, describing their distribution, activity and main structural characteristics. 相似文献
10.
Consiglio A Grillo G Licciulli F Ceci LR Liuni S Losito N Volpicella M Gallerani R De Leo F 《Current protein & peptide science》2011,12(5):448-454
PlantPIs is a web querying system for a database collection of plant protease inhibitors data. Protease inhibitors in plants are naturally occurring proteins that inhibit the function of endogenous and exogenous proteases. In this paper the design and development of a web framework providing a clear and very flexible way of querying plant protease inhibitors data is reported. The web resource is based on a relational database, containing data of plants protease inhibitors publicly accessible, and a graphical user interface providing all the necessary browsing tools, including a data exporting function. PlantPIs contains information extracted principally from MEROPS database, filtered, annotated and compared with data stored in other protein and gene public databases, using both automated techniques and domain expert evaluations. The data are organized to allow a flexible and easy way to access stored information. The database is accessible at http://www.plantpis.ba.itb.cnr.it/. 相似文献