We tabulate the atomic mass excesses and binding energies, ground-state shell-plus-pairing corrections, ground-state microscopic corrections, and nuclear ground-state deformations of 9318 nuclei ...ranging from 16O to A=339. The calculations are based on the finite-range droplet macroscopic and the folded-Yukawa single-particle microscopic nuclear-structure models, which are completely specified. Relative to our FRDM(1992) mass table in Möller et al. (1995), the results are obtained in the same model, but with considerably improved treatment of deformation and fewer of the approximations that were necessary earlier, due to limitations in computer power. The more accurate execution of the model and the more extensive and more accurate experimental mass data base now available allow us to determine one additional macroscopic-model parameter, the density-symmetry coefficient L, which was not varied in the previous calculation, but set to zero. Because we now realize that the FRDM is inaccurate for some highly deformed shapes occurring in fission, because some effects are derived in terms of perturbations around a sphere, we only adjust its macroscopic parameters to ground-state masses.
The values of ten constants are determined directly from an optimization to fit ground-state masses of 2149 nuclei ranging from 16O to 106265Sg and 108264Hs. The error of the mass model is 0.5595 MeV for the entire region of nuclei included in the adjustment, but is only 0.3549 MeV for the region N≥65.
We also provide masses in the FRLDM, which in the more accurate treatments now has an error of 0.6618 MeV, with 0.5181 MeV for nuclei with N≥65, both somewhat larger than in the FRDM. But in contrast to the FRDM, it is suitable for studies of fission and has been extensively so applied elsewhere, with FRLDM(2002) constants. The FRLDM(2012) fits 31 fission-barrier heights from 70Se to 252Cf with a root-mean-square deviation of 1.052 MeV.
It is well known that most actinides fission into fragments of unequal size. This contradicts liquid-drop-model theory from which symmetric fission is expected. The first attempt to understand this ...difference suggested that division leading to one of the fragments being near doubly magic 132Sn is favored by gain in binding energy. After the Strutinsky shell-correction method was developed an alternative idea that gained popularity was that the fission saddle might be lower for mass-asymmetric shapes and that this asymmetry was preserved until scission. Recently it was observed Phys. Rev. Lett. 105 (2010) 252502 that 180Hg preferentially fissions asymmetrically in contradiction to the fragment-magic-shell expectation which suggested symmetric division peaked around 90Zr, with its magic neutron number N=50, so it was presented as a “new type of asymmetric fission”. However, in a paper Phys. Lett. B 34 (1971) 349 a “simple” microscopic mechanism behind the asymmetry of the actinide fission saddle points was proposed to be related to the coupling between levels of type 40ΛΩ and 51ΛΩ. The paper then generalizes this idea and made the remarkable prediction that analogous features could exist in other regions. In particular it was proposed that in the rare-earth region couplings between levels of type 30ΛΩ and 41ΛΩ would favor mass-asymmetric outer saddle shapes. In this picture the asymmetry of 180Hg is not a “new type of asymmetric fission” but of analogous origin as the asymmetry of actinide fission. This prediction has never been cited in the discussion of the recently observed fission asymmetries in the “new region of asymmetry”, in nuclear physics also referred to as the rare-earth region. We show by detailed analysis that the mechanism of the saddle asymmetry in the sub-Pb region is indeed the one predicted half a century ago.
Aim
Phase angle (PhA) can be determined through bioelectrical impedance analysis and is a unique variable for skeletal muscle. The objective of this study was to evaluate the relationship between PhA ...and muscle mass/quality in older adults. In addition, we attempted to determine the cutoff value of PhA for poor muscle function.
Methods
Community-dwelling Japanese older men (n=285, 81.1±7.1 years) and women (n=724, 80.4±6.8 years) participated in this study and were classified into four groups based on the Asian Working Group for Sarcopenia (normal, presarcopenia, dynapenia, and sarcopenia). We measured PhA using bioelectrical impedance analysis, muscle quantity and quality indicators using ultrasonography, muscle strength, and physical performance and compared them in four groups. We also tried to determine the cutoff value of PhA for poor muscle function.
Results
We found a significant difference in PhA among the four groups in men (P<0.05), and the dynapenia (3.61±0.75°) and sarcopenia groups (3.40±0.74°) showed significantly lower values than the normal group (4.50±0.86°) (P<0.05), but not the presarcopenia group (4.12±0.85°). In women, a significant difference was also observed among the four groups (P<0.05), and the dynapenia (3.41±0.65°) and sarcopenia groups (3.31±0.66°) showed significantly lower measures than the normal group (4.14±0.71°) (P<0.05), but not the presarcopenia group (4.07±0.51°). The receiver-operating characteristic curve analysis indicated the best cutoff value of PhA (men: 4.05°, women: 3.55°) to discriminate sarcopenia and dynapenia from normal and presarcopenia.
Conclusion
These findings suggest that PhA is a useful indicator for muscle function.
Zirconium tetrachloride (ZrCl4) is one of the best catalysts for improving the reversible hydrogen storage performance of the MgH2–Mg system. MgH2 catalyzed by ZrCl4 shows a remarkably reduced ...apparent activation energy, which leads to improved dehydrogenation and rehydrogenation kinetics. X-ray photoelectron spectroscopy (XPS) revealed the chemical state of ZrCl4 as ZrCl3 and metallic Zr after ball milling with MgH2. The in situ-formed ZrCl3 and metallic Zr showed good catalytic effect on MgH2, which substantially lowered the dehydrogenation and rehydrogenation temperatures. The scanning electron microstructure analysis revealed the excellent grain refinement property of the catalyst to reduce the crystallite size of MgH2 during ball-milling. The decreased crystallite size reduces the diffusion path length of hydrogen and increases the active surface area of MgH2–Mg, which eventually enhances the dehydrogenation and rehydrogenation kinetics.
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•Cyclic performance of ZrCl4-doped MgH2 was studied.•ZrCl4-doped Mg could be rehydrogenated at room temperature.•Activation energy of hydrogen absorption-desorption of c-Mg was significantly reduced.•ZrCl4 was reduced to ZrCl3 and Zr by MgH2, which acts as a catalyst.
The thermal desorption processes of hydrogen (H2) and methane (CH4) from lithium-based materials, Li2ZrO3 and Li4SiO4, exposed to air at room temperature of 293 K with a relative humidity of 80%, ...were investigated using gas chromatography (GC). The GC analysis revealed that the absolute values of the released H2 and CH4 gases at 523 K were approximately 7.42 × 10−6 and 1.54 × 10−6 ml/g for Li2ZrO3, and 3.24 × 10−6 and 0 ml/g for Li4SiO4. The amounts of H2 and CH4 released increased with increase in annealing temperatures and considerably depended on absorption properties of water (H2O) and carbon dioxide (CO2) present in air at room temperature. The production of CH4 at low temperature is due to the intermediate species including CHx precursors produced by the reaction between H split from H2O and Li2CO3 resulting in the CO2 absorption of Li2ZrO3 and Li4SiO4 materials.
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•Thermal desorption processes of H2 and CH4 from air-exposed Li2ZrO3 and Li4SiO4 were investigated by gas chromatography.•H2 and CH4 were released at low temperatures less than 523 and 773 K for air-exposed Li2ZrO3 and Li4SiO4, respectively.•The production of CH4 at low temperature is due to the reaction between H split from H2O and Li2CO3.
Marine planktonic copepods are an ecologically important group with high species richness and abundance. Here, we propose a new metagenetic approach for revealing the community structure of marine ...planktonic copepods using 454 pyrosequencing of nuclear large subunit ribosomal DNA. We determined an appropriate similarity threshold for clustering pyrosequencing data into molecular operational taxonomic units (MOTUs) using an artificial community containing 33 morphologically identified species. The 99% similarity threshold had high species‐level resolution for MOTU clustering but overestimated species richness. The artificial community was appropriately clustered into MOTUs at 97% similarity, with little inflation in MOTU numbers and with relatively high species‐level resolution. The number of sequence reads of each MOTU was correlated with dry weight of that taxon, suggesting that sequence reads could be used as a proxy for biomass. Next, we applied the method to field‐collected samples, and the results corresponded reasonably well with morphological analysis of these communities. Numbers of MOTUs were well correlated with species richness at 97% similarity, and large numbers of sequence reads were generally observed in MOTUs derived from species with large biomass. Further, MOTUs were successfully classified into taxonomic groups at the family level at 97% similarity; similar patterns of species richness and biomass were revealed within families with metagenetic and morphological analyses. At the 99% similarity threshold, MOTUs with high proportions of sequence reads were identified as biomass‐dominant species in each field‐collected sample. The metagenetic approach reported here can be an effective tool for rapid and comprehensive assessment of copepod community structure.
Summary
Candida albicans is a commonly found member of the human microflora and is a major human opportunistic fungal pathogen. A perturbation of the microbiome can lead to infectious diseases caused ...by various micro‐organisms, including C. albicans. Moreover, the interactions between C. albicans and bacteria are considered to play critical roles in human health. The major biological feature of C. albicans, which impacts human health, resides in its ability to form biofilms. In particular, the extracellular matrix (ECM) of Candida biofilm plays a multifaceted role and therefore may be considered as a highly attractive target to combat biofilm‐related infectious diseases. In addition, extracellular DNA (eDNA) also plays a crucial role in Candida biofilm formation and its structural integrity and induces the morphological transition from yeast to the hyphal growth form during C. albicans biofilm development. This review focuses on pathogenic factors such as eDNA in Candida biofilm formation and its ECM production and provides meaningful information for future studies to develop a novel strategy to battle infectious diseases elicited by Candida‐formed biofilm.
Successful feeding on preferred prey could be important for the survival of fish larvae. However, high taxonomic resolution of prey types from damaged gut contents is difficult to achieve through ...morphological classification, especially for fragile organisms or immature stages. In this study, <10 mm early post-larvae of Japanese sardine Sardinops melanostictus and Pacific round herring Etrumeus teres were collected from Tosa Bay (Japan) during their main spawning periods. Diet and plankton communities present in the environment were investigated using molecular operational taxonomic units (MOTUs) clustered using eukaryoticmetagenetic data fromthe 18S V9 region. There were no clear differences in the diets of the co-existing fish species. Fragile protists and gelatinous metazoans occasionally represented large proportions of gut content; however, copepods comprised the majority of the prey items. Among the copepods, the Calanidae MOTU derived fromthe large copepod Calanus sinicus was most consumed, followed by the Paracalanidae MOTU identified as small Paracalanus parvus s.l. The C. sinicus MOTU largely dominated intermediate (0.5–1.0 mm) and large (1.0–2.0 mm) environmental mesoplankton communities, whereas the P. parvus s.l. MOTU was the most dominant in small-sized (0.1–0.5 mm) communities. Early post-larvae fish were considered to prefer eggs or nauplii of C. sinicus, which was the second-dominant MOTU in small-sized communities. These results suggested that both food availability and developmental stages of copepods determined prey preference.
The effect of vanadium doping on the kinetics and thermodynamics of hydrogenation–dehydrogenation process of Mg2Ni have been investigated. Two samples, Mg2Ni-5 wt.% V and Mg2Ni-10 wt.% vanadium were ...prepared by ball milling process. The hydrogenation–dehydrogenation kinetics along with pressure–composition isotherm (PCT) of vanadium doped and pure-Mg2Ni samples were studied. The sample Mg2Ni-5 wt.% V has shown improved hydrogenation–dehydrogenation kinetics with extended plateau region as compared to pure-Mg2Ni under similar conditions. Marginal changes in the enthalpies of hydrogenation–dehydrogenation have been observed on vanadium addition. The improved properties could be beneficial for the viable commercial applications of Mg2Ni as a negative electrode of metal-hydride batteries and as a material for hydrogen storage.
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•Hydrogen storage capacity increase on vanadium addition.•H-sorption kinetics improved on vanadium addition.•Plateau region have been extended and flatten on vanadium addition.•Extended plateau will help to increase the discharge duration in Ni-MH battery.
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