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[en] We develop a stochastic approach to obtain the energies and wave functions of the full spectrum of the nuclear pairing Hamiltonian (i.e. not only the ground-state but also the excited states of the nuclear many-body systems). We assume that nuclear Cooper pairs may spontaneously jump from one energy configuration to another, the mechanism resembling that of the random walk on a mesh of non-equidistant points. A probability distribution associated with such a random walk is modelled and the resulting solutions tested using an exact quantum algorithm. We use the Hamiltonian parameters characteristic for the nuclear scale: at present an agreement between the quantum and stochastic treatment is of the order of a few per mille in terms of eigen-energies. (author)
Journal
International Journal of Modern Physics E; ISSN 0218-3013; 
; v. 13(1); p. 203-211
; v. 13(1); p. 203-211
[en] We present a model which allows for the calculation of fragment excitation energy, fragment kinetic energies and neutron evaporation in nuclear fission. The model is based on the assumption that, at the end of the fission process, fragments are excited to a temperature which is proportional to the reaction Q-value. Starting from this assumption the distribution functions of fragment excitation can be formulated and the distribution functions for the kinetic energies can be derived by a Monte Carlo method. From the distribution functions for the excitation energy neutron evaporation characteristics are calculated. (author)
Journal
International Journal of Modern Physics E; ISSN 0218-3013; ; v. 13(1); p. 321-326
; v. 13(1); p. 321-326
[en] A nonlinear supersymmetric (NLSUSY) Einstein–Hilbert (EH)-type new action for the unity of nature is obtained by performing Einstein gravity analogue geometrical arguments in high symmetry spacetime inspired by NLSUSY. The new action is unstable and breaks down spontaneously into the EH action with matter in ordinary Riemann spacetime. All elementary particles except the graviton are composed of the fundamental fermion 'superon' (the Nambu–Goldstone (NG) fermion of NLSUSY) and regarded as the eigenstates of SO(10) super-Poincare (SP) algebra, called the superon-graviton model (SGM) of nature. Some phenomenological implications for low energy particle physics and cosmology are discussed. The linearization of NLSUSY including N=1 SGM action is attempted explicitly to obtain the linear SUSY local field theory, which is equivalent and renormalizable. (author)
Journal
International Journal of Modern Physics E; ISSN 0218-3013; ; v. 13(3); p. 539-571
; v. 13(3); p. 539-571
[en] Calculations of the 6,8He+28Si total reaction cross-sections at intermediate energies are performed on the basis of the Glauber–Sitenko microscopic optical-limit model. The target-nucleus density distribution is taken from the electron-nucleus scattering data, and the 6,8He densities are used as they are derived in different models. The results of the calculations are compared with existing experimental data. The effects of the density tails of the projectile nuclei as well as the role of shell admixtures and short-range correlations are analyzed. (author)
Journal
International Journal of Modern Physics E; ISSN 0218-3013; ; v. 13(3); p. 573-583
; v. 13(3); p. 573-583
[en] The E subunit of vacuole-type ATPase from P. horikoshii OT3 was overexpressed, purified and crystallized. The native crystals diffracted X-rays to 1.85 Å resolution. The vacuole-type ATPases in eukaryotic cells translocate protons across various biological membranes including the vacuolar membrane by consuming ATP molecules. The E subunit of the multisubunit complex V-ATPase from Pyrococcus horikoshii OT3, which has a molecular weight of 22.88 kDa, has been cloned, overexpressed in Escherichia coli, purified and crystallized by the microbatch method using PEG 4000 as a precipitant at 296 K. A data set to 1.85 Å resolution with 98.8% completeness and an Rmerge of 6.5% was collected from a single flash-cooled crystal using synchrotron radiation. The crystal belonged to the orthorhombic space group P212121, with unit-cell parameters a = 52.196, b = 55.317, c = 77.481 Å, and is most likely to contain one molecule per asymmetric unit
Journal
[en] The binding of Cu2+ ions to the copper-binding domain of the amyloid precursor protein of Alzheimer’s disease reduces the production of the amyloid β peptide, which is centrally involved in Alzheimer’s disease. Structural studies of the copper-binding domain will provide a basis for structure-based drug design that might prove useful in treating this devastating disease. Alzheimer’s disease is thought to be triggered by production of the amyloid β (Aβ) peptide through proteolytic cleavage of the amyloid precursor protein (APP). The binding of Cu2+ to the copper-binding domain (CuBD) of APP reduces the production of Aβ in cell-culture and animal studies. It is expected that structural studies of the CuBD will lead to a better understanding of how copper binding causes Aβ depletion and will define a potential drug target. The crystallization of CuBD in two different forms suitable for structure determination is reported here
Journal
No abstract available
Journal
Informatore Agrario; ISSN 0020-0689; ; v. 60(1); p. 51-54
; v. 60(1); p. 51-54
[en] Boerhavia diffusa is a medicinally important plant and finds extensive uses in traditional herbal drug preparations. For the development of improved varieties in terms of superior yield and quality of herb/root of B. diffusa, mutation breeding was attempted. Mutants generated by physical and chemical mutagenic treatments were screened for yield and quality parameters of the root/herb up to three consecutive generations. The selected-screened lines generated by physical and chemical mutagenic treatments on two selected genotypes I and II were molecularly analyzed using eight isozymes and eleven RAPD primers producing good amplification. Mutants from BD10 (selected genotype I) were distinct, while, in case of BD22 (selected genotype II), only one mutant BDMu7 was recorded distinct by isozyme analysis. The wild mutant (BDMu16, with maximum height and mouve coloured flower) was distinct in RAPD banding pattern. Isozymes differentiated the mutants from their respective controls, whereas RAPD differentiated the mutants and controls and also distinguished the mutants. The RAPD analysis was found to be better suited than isozymes for detecting genetic differences among controls and their mutants. However, both RAPD and isozyme analyses gave similar patterns of genetic relationships
[it]
Boerhavia diffusa è una pianta importante dal punto di vista medicinale trova largo impiego nelle preparazioni farmaceutiche tradizionali a base di erbe. Per lo sviluppo di varietà migliorate in termini di resa superiore e qualità dei germogli e radici di B. diffusa, è stata sperimentato il miglioramento genetico tramite mutazioni. I mutanti generati da trattamenti mutagenici fisici e chimici sono stati saggiati in ordine ai parametri quantitativi e qualitativi del germoglio/radice fino a tre generazioni consecutive. Le linee selezionate-controllate generate da trattamenti mutageni fisici e chimici su due genotipi selezionati I e II sono stati analizzati dal punto di vista molecolare utilizzando otto isoenzimi e 11 primer RAPD che producevano una buona amplificazione. I mutanti di BD10 (genotipo selezionato I) venivano distinti, mentre, nel caso di BD22 (genotipo selezionato II), solo un mutante BDMu7 è stato registrato come distinto tramite analisi isoenzimatica. Il mutante spontaneo (BDMu16, con altezza massima e fiore color malva) veniva distinto nella configurazione di bandeggio RAPD. Gli isoenzimi hanno differenziato i mutanti dai rispettivi controlli, mentre il RAPD differenziava i mutanti e i controlli e distingueva pure i mutanti. L´analisi RAPD risultava migliore degli isoenzimi per individuare le differenze genetiche nell´ambito dei controlli e dei loro mutanti. Tuttavia, sia il RAPD, sia gli isoenzimi hanno fornito tipi simili di relazioni geneticheJournal
Journal of Genetics and Breeding; ISSN 0394-9257; ; v. 58(1); p. 37-46
; v. 58(1); p. 37-46
[en] An experiment on induced mutation in two varieties of opium poppy was laid out to create new genetic variability for isolation of high yielding genotypes. Varieties NBRI-1 and NBRI-5 were subjected to irradiation for five doses of gamma rays and NBRI-5 was also treated with four doses of EMS and 20 mixed doses of EMS plus gamma rays. The data were recorded on 15 plants/treatment for 10 polygenic characters as pooled in M1 and M2 generations separately as well as in each dose-wise in M2 population. The results indicated that GCV, heritability and genetic advance were higher in M1 than M2 in both the varieties for all the traits except for opium and seed yield. The genetic advance was consistently high for opium yield, seed yield and capsule weight in all the doses for both the varieties with some exception. The dose level of kR10 and kR30 in NBRI-1 revealed high GCV, heritability and genetic advance for seed weight. These treatment levels also had high values of all these three genetic parameters for capsules per plant, capsule size and capsule weight. The values of these three parameters were also high for all the doses in M2 generations of both the varieties for opium yield, seed weight, capsule weight and capsule size in comparison to control. The GCV, heritability and genetic advance were consistently high for all the mixed doses in NBRI-5 for opium yield, seed weight and capsule weight, with some exception
[it]
E´ stato impostato un esperimento di mutazione indotta in due varietà di papavero da oppio per creare nuova variabilità genetica per l´isolamento di genotipi ad alta resa. Le varietà NBRI-1 e NBRI-5 sono state sottoposte a irradiazione con cinque dosi di raggi gamma e NBRI-5 è stata pure trattata con quattro dosi di EMS e 20 dosi miste di EMS più raggi gamma. Su 15 piante/trattamento sono stati registrati i dati relativi a 10 caratteri in complesso, separatamente per le generazioni M1 ed M2 e per ogni dose nella generazione M2. I risultati hanno indicato che la GCV, l´ereditabilità e il guadagno genetico erano più elevati in M2 rispetto a M1 in ambedue le varietà per tutti i caratteri, a eccezione della resa in oppio e in seme. Il guadagno genetico era costantemente elevato per la resa in oppio, la resa in seme e il peso delle capsule in tutte le dosi per ambedue le varietà, con qualche eccezione. I livelli di dose kR10 e kR30 in NBRI-1 hanno evidenziato alti GCV, ereditabilità e guadagno genetico per il peso dei semi. Questi livelli di trattamento presentavano inoltre valori elevati di tutti e tre i parametri genetici per il numero di capsule per pianta, le dimensioni e il peso delle capsule. I valori di questi tre parametri erano elevati anche per tutte le dosi nelle generazioni M2 di ambedue le varietà di oppio relativamente alla resa in oppio, al peso dei semi, al peso e alla dimensione delle capsule in confronto al controllo. GCV, ereditabilità e guadagno genetico sono risultati costantemente elevati per tutte le dosi miste in NBRI-5 relativamente alla resa in oppio, al peso dei semi e delle capsule, con qualche eccezioneJournal
Journal of Genetics and Breeding; ISSN 0394-9257; ; v. 58(4); p. 319-322
; v. 58(4); p. 319-322
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