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71.
Schürmann D. Di Leva A. Gialanella L. De Cesare M. De Cesare N. Imbriani G. D’Onofrio A Romano M. Romoli M. Terrasi F. 《The European Physical Journal A - Hadrons and Nuclei》2013,49(6):1-10
Using the Coulomb and proximity potential model (CPPM) we have investigated the cluster decays of the isotopes 212-240Pa, 219-245Np, 228-246Pu, 230-249Am and 232-252Cm leading to doubly magic 208Pb and its neighboring nuclei, which are not experimentally detected but which may be detectable in the future. It is found that most of the decays are favourable for experimental measurements (i.e., $T_{1/2}<10^{30}$ s) and this observation will serve as a guide to future experiments. Our study reveals the role of doubly magic 208Pb daughter nuclei and near doubly magic nuclei in the cluster decay process. In order to make a comparison with CPPM we also calculated the logarithmic half-lives using the Universal formula for the cluster decay (UNIV) by Poenaru et al., the Universal Decay Law (UDL) and the Scaling Law of Horoi et al., and they are found to be in good agreement. The Geiger-Nuttall plots of $log_{10}(T_{1/2})$ versus $Q^{-1/2}$ for various clusters from different isotopes of heavy parent nuclei have been studied and are found to be linear. 相似文献
72.
Lapolla A Molin L Seraglia R Sechi A Cosma C Bonfante L Chilelli NC Ragazzi E Traldi P 《European journal of mass spectrometry (Chichester, England)》2011,17(3):245-253
The development of new analytical methodologies related to the proteome for the evaluation of renal physiology and pathology is surely of wide interest for physicians, giving them new tools for monitoring complications associated with diabetes, such as end-stage renal disease. In the present study, the clinical significance of the urinary abundance of two peptides, SGSVIDQSRVLNLGPITR (the uromodulin precursor, m/z 1912) and IGPHypGPHypGLMGPP [present in the collagen-α-5(IV) chain precursor, m/z 1219], detected by matrix- assisted laser desorption/ionisation mass spectrometry (MALDI/MS) in microalbuminuric or nephropathic diabetic patients and in non-diabetic nephropathic patients was evaluated. A progressive increase in the abundance of the ion at m/z 1219 and a decrease in the abundance of the ion at m/z 1912 have been found in diabetic microalbuminuric, diabetic-nephropathic and nephropathic patients. Linear correlations are present between serum creatinine values and the abundances of the ions at m/z 1219 (positive correlation, r=0.3645, P<0.0001) and at m/z 1912 (negative correlation, r=-0.3053, P<0.0005). Correlations between the MALDI data and the estimated glomerular filtration rate were also found, while relationships with urinary albumin excretion were found only in sub-sets of patients. Analysis of receiver operating characteristic curves showed a sensitivity up to 96% and a specificity of up to 84% for the two ionic species, or their ratio, for distinguishing diabetic patients with different degrees of nephropathy from healthy subjects, proving that the urinary abundance of the two peptides at m/z 1219 and m/z 1912, determined with MALDI/MS, may be considered as a possible diagnostic tool for the determination of progression toward renal failure, also with the aim of monitoring kidney function, in diabetic patients. 相似文献
73.
Let K be a commutative ring with unity, R a prime K-algebra, Z(R) the center of R, d and δ nonzero derivations of R, and f(x 1,…, x n ) a multilinear polynomial over K. If [d(f(r 1,…, r n )), δ (f(r 1,…, r n ))] ? Z(R), for all r 1,…, r n ? R, then either f(x 1,…, x n ) is central valued on R or {d, δ} are linearly dependent over C, the extended centroid of R, except when char(R) = 2 and dim C RC = 4. 相似文献
74.
Bruno Buonomo Alberto d’Onofrio 《Journal of Optimization Theory and Applications》2013,158(2):554-575
We consider the problem of a rational politician who gains benefit from both being popular and corrupt. In 1994, Feichtinger and Wirl studied this trade-off by means of an infinite-horizon optimal control approach. We reconsider the problem over a finite time horizon, to model the dilemma of a politician who stays in office for a limited period of time and wishes to be reelected. We also include explicitly the possibility that awareness of politician’s conduct to the general population is delayed and the effect of such delay on the politician’s optimal behavior is analyzed. We show the outcomes under several different scenarios, with particular reference to the role of the politician’s communication skills. One general conclusion is that the synergy of a good public’s memory and immediate knowledge of corruption may often help the people to protect themselves from political corruption. Moreover, this synergy may greatly enhance the popularity of a politician with poor communication skills, provided that he/she aims at maximizing benefit from popularity during his/her mandate. 相似文献
75.
Silvia Burlina Cristina Banfi Maura Brioschi Silvia Visentin Maria Grazia Dalfr Pietro Traldi Annunziata Lapolla 《Journal of mass spectrometry : JMS》2019,54(4):359-365
In pregnancy complicated by gestational diabetes mellitus (GDM), the human placenta shows several pathological functional and structural changes, but the extent to which maternal glycemic control contributes to placental abnormalities remains unclear. The aim of this study was to profile and compare the proteome of placentas from healthy pregnant women and those with GDM, to investigate the placenta‐specific protein composition and possible changes of its function in presence of GDM. Quantitative proteomic analysis, based on LC‐MSE approach, revealed that higher (approximately 15% increase) levels of galectin 1 and collagen alpha‐1 XIV chain (although the difference regarding the latter was at the limit of significance) were present in GDM samples, while heat shock 70 kDa protein 1A/1B was less abundant in GDM placental tissue. These data seem to indicate that GDM, when well controlled, did not markedly affect the placental proteome. 相似文献
76.
A. Formicola M. Aliotta G. Gyürky F. Raiola R. Bonetti C. Broggini L. Campajola P. Corvisiero H. Costantini A. D’Onofrio Z. Fülöp G. Gervino L. Gialanella A. Guglielmetti C. Gustavino G. Imbriani M. Junker A. Ordine P. Prati V. Roca D. Rogalla C. Rolfs M. Romano F. Schümann E. Somorjai O. Straniero F. Strieder F. Terrasi H. P. Trautvetter S. Zavatarelli 《The European Physical Journal A - Hadrons and Nuclei》2000,8(4):443-446
The energy loss of deuterons in 3He gas was measured at E d = 15 to 100 keV using the 3He pressure dependence of the 3He(d,p)4He cross-section at a given incident energy. At the highest energies, the observed energy loss is in good agreement with a standard compilation. However, with decreasing energy the experimental values drop steadily below the theoretical values and near E d = 18 keV they drop sharply (within 1 keV) reaching the domain of nuclear stopping power. This threshold behavior is due to the minimum 1s → 2s electron excitation of the He target atoms, i.e. it is a quantum effect. Some consequences are discussed. 相似文献
77.
The 33S chemical shifts, δ, and the line widths of selected sulphones, sulphoximides, sulphimides, sulphides and sulphonium ions were measured at 23.009 MHz. δ increased with decreasing electronic charge on sulphur. The line width varied from 3–10 ppm for sulphones to 400 ppm for sulphonium ions. The higher geometrical flexibility of five-membered ring sulphones with respect to the six-membered ring compounds was reflected in the variations of δ with methyl substitution. Open-chain sulphoximides are shielded with respect to the corresponding sulphones, whereas open-chain sulphimides are deshielded with respect to the corresponding sulphoximides. 相似文献
78.
79.
Simonetta Orlandi Marinella Caporale Maurizio Benaglia Rita Annunziata 《Tetrahedron: Asymmetry》2003,14(24):3827-3830
Starting from the commercially available enantiopure (1S,2S)-2-amino-1-phenyl-1,3-propanediol novel enantiomerically pure benzimidazoles were prepared; N-alkylation gave chiral benzimidazolium salts, which were tested in asymmetric benzoin condensations. The synthesis of conceptually new, enantiomerically pure, C2 symmetric bis-thiazolium and bis-benzimidazolium salts was also developed. These new chiral heterocycles were employed as catalysts in the asymmetric dimerisation of benzaldehyde to give benzoin with moderate enantioselectivity. 相似文献
80.
Annunziata Palumbo Giovanna Valenti 《Mathematical Methods in the Applied Sciences》2002,25(11):945-954
A predator–prey model is proposed within the general scheme of extended thermodynamics. An additional equation of balance is needed to account for the flux of the number density of the predator as an independent field variable. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献