Heavy Particle Accompanied Fission of 284Og - A Statistical Model Study

The structural characteristics of SHN can be investigated through the decay of SHN. In the present work ternary fission of SHN 284Og for two proton magic fixed third fragment 48Ca and 68Ni is studied at three different excitation energies 20, 35 and 50 MeV. Interestingly, 169Yb + 67Ni + 48Ca is having larger yield values and hence it is the most favoured way of fragmentation at intermediate excitation energy 35 MeV. It is observed that, asymmetric fission is favoured over symmetric fission at all the excitation for the third fragment 48Ca. Asymmetric fission is the most favoured with the fragment combination 148Sm + 68Ni + 68Ni for fixed A3 = 68Ni at all the excitations. Unlike the Ca third fragment, near symmetric fission is also favoured with 113Ag + 103Tc + 68Ni for A3 = 68Ni at all the three excitation energies.

Transformations of actinides fission product yields due to post scission emission of nuclear particles:232Th

The "many ensembles" method was proposed to investigate the influence of nuclear particles' post-scission emission on mass and charge distributions of fission products. The post scission approximation had been used; each of these ensembles consists of the fission fragments after emission of chains of different lengths, both the beta (±β) particles and neutrons. The theory allows one to find the most probable two fragment clusters of fission products and study their evolution after the post-scission emission of nuclear particles. The isotope ²³²Th was chosen as an example, the fission fragments of which are intensively studied in the experiment. It is shown that the post-scission emission of nuclear particles eventually leads to the convergence of the asymmetric peaks, which looks like enhanced symmetric fission mode over asymmetric one for fission product yields. A comparison of the theoretical results and experimental data for the ²³²Th fission fragments indicates their satisfactory matching.

Asymmetric crypt fission in colectomy specimens in patients with ulcerative colitis

AimsWe previously found colonic crypts with asymmetric fission bordering regenerating ulcers in ulcerative colitis (UC). The present objective was to assess the frequency of asymmetric crypt-fission in colectomy specimens from patients with long-lasting UC.MethodsH&E-stained sections from seven colectomies from patients with UC without dysplasia or carcinoma were investigated. Symmetric fission was characterised by branched colon crypts showing ≥2 identical crypts, whereas asymmetric fission exhibited branched colon crypt portraying ≥2 dissimilar crypts, differing in diameter, length and/or shape.ResultsThe number of crypts in fission in the 89 sections was 3586; of those, 2930 (81.7%) were asymmetric and the remaining 656 (18.3%), symmetric. Out of 927 vertically-cut crypts (in well-oriented sections), 912 (98.4%) were asymmetric, and the remaining 14 (1.6%), symmetric, and out 2660, cross-cut (transected) crypts in fission, 2018 (75.9%) were asymmetric and the remaining 642 (24.1%), symmetric.ConclusionCrypt fission is rarely found in the normal colon in adults. Symmetric crypt fission found in UC is possibly triggered by a compensatory homeostatic mechanism of crypt production in mucosal areas replaced by chronic inflammation. But asymmetric crypt fission is a pathological aberration that affects crypts in patients with a particular predisposition to develop mucosal dysplasia. It is suggested that this previously unattended histological parameter be included in the pathological descriptions of colectomy specimens from patients with UC.

Significance of Neutrino Environments on Neutrino-Induced Fission and Neutron-Induced Fission Processes

This paper presents Mathematical Formulation for Neutrino-Fission of a heavy nuclei in Neutrino-environments. It has been proposed that neutrino fission is a dynamic two-process reaction, where more than one neutrino can be captured by target nucleus. A quantity named Neutrino-Zeta with units of eV-1 has been defined to represent Neutrino-environments. Neutrino-zeta with assumed excited energy states for heavy nuclei A∼230-270 is estimated to be 0.0212 MeV-1, with the probability of fission Barrier energy state P(Ex,f)= 0.169064014 with Ex,f =6MeV. P(Ex,f)=0.222664 is highest at zeta=0.1MeV-1 . It has been shown that probabilities of certain excitation energy states and their corresponding decay reactions at those excitation energies can be equal for two neutrino-zetas. Neutron induced fission for different neutrinos hypothesize that probability of symmetric fission channels is higher at low neutrino-zetas, which can be tested experimentally.

Asymmetric crypt fission in sessile serrated lesions

ObjectiveSessile serrated lesions without dysplasia (SSL-ND) are epitomised by dilated crypts with epithelial serrations and architectural distortions portraying boot-shapes, L-shapes or inverted-T shapes. Recently, crypts in asymmetric fission were detected in SSL-ND. The purpose was to assess the frequency of crypts in asymmetric fission in a cohort of SSL-ND.MethodsThe frequency of crypts in fission was assessed in 60 SSL-ND, the distribution of cell proliferation in 48 SSL-ND and the expression of maspin, a tumour-suppressor protein, in 29 SSL-ND.ResultsOut of the 60 SSL-ND, 40 (66.7%) showed crypts in fission: 39 (65%) SSL-ND had crypts in asymmetric fission and one SSL-ND (1.7%), in symmetric fission (p<0.05). Of 1495 crypts recorded in the 60 SSL-ND, 73 (4.9%) were in asymmetric fission but only one (0.06%), in symmetric fission (p<0.05). Out of the 48 Ki67-immunostained SSL-ND,15 (31%) showed randomly distributed proliferating cell-domains. All 29 SSL-ND revealed maspin-upregulation (including crypts in asymmetric and symmetric fission). In contrast, the normal colon mucosa showed occasional single crypts in symmetric fission, proliferating cell-domains limited to the lower thirds of the crypts, absence of crypts in asymmetric fission and remained maspin negative.ConclusionsSSL-ND thrive with crypts in asymmetric fission displaying randomly distributed proliferating cell-domains and maspin-upregulation. These histo-biological aberrations disclose pathological cryptogenesis and suggest possibly unfolding somatic mutations in SSL-ND. The present findings may open new vistas on the parameters pertinent to the susceptibility of SSL-ND to develop dysplasia and carcinoma.

Monte-Carlo calculation of fission process for neutron-induced typical actinide nuclei fission

A global potential-driving model with well-determined parameters is proposed by uniting the empirical asymmetric fission potential and the empirical symmetric fission potential, which can precisely calculate the pre-neutron-emission mass distributions for neutron-induced actinide nuclei fission. Based on the developed potential-driving model, Monte-Carlo code calculates the characteristics of fission reaction process for neutron-induced 241 Am fission. Typical calculated results, including yields, kinetic energy distributions, fission neutron spectrum and decay γ-ray spectrum, are compared with experimental data and evaluated data. It shows that the Monte-Carlo calculated results agree quite well with the experiment data, which indicate that Monte-Carlo code with the developed potential-driving model can reproduce and predict the characteristics of fission reaction process at reasonable energy ranges. Given the well predictions on the characteristics of fission reaction process, Monte-Carlo code with the developed potential-driving model can guide for the physical design of nuclear fission engineering.