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Both amorphous and liquid As2Se3 exhibit fast decrease of optical transmittance under a nanosecond pulsed laser excitation. This light-induced effect is called fast photodarkening (PD). After the cessation of excitation (one shot), the PD recovers within 0.1 s, but remains in a wide time domain from 10–7 to 10–2 s. Dynamic responses of the PD-recovery are studied through the autocorrelation function (ACF) in time domain and the power spectrum (PS) in frequency domain. The first zero-crossing time in the ACF, τ0, a measure of decay time in the relaxation process, is scaled with the time interval of the original measured data, tm, with the relationship, τ0 ∝ tmγ (γ ~ 1.0) in both the amorphous and liquid states. The PS is described by 1/fα (α = 0.8–0.9). Both the ACF and PS results indicate that the structural relaxation of the As–Se network occurs with similar decay processes in "any" time region, which can be inferred to have fractal nature in time domain. [ABSTRACT FROM AUTHOR]

Grain yield of rice consists of sink capacity and grain filling. There are some genes known to contribute to sink capacity, but few genes associated with grain filling are known. We conducted a genetic analysis on yield-related traits by using a chromosome segment substitution line population that have introgression from DV85, an aus variety of rice, in the background of T65, a japonica variety. Refined whole-genome genotypes of the 43 TD-CSSLs were obtained by genotyping-by-sequencing. The effects of previously detected quantitative trait loci (QTLs), qNSC1 and qNSC2 , were confirmed by the amount of non-structural carbohydrate (NSC) at 5 days after heading (DAH). The CSSL for qSWTR11 , the QTL for decrease in shoot weight during the maturity stage, showed the highest NSC at 5 DAH and lowest at 35 DAH. The brown rice yield of these lines were not stably significant. Most of the sink-related traits correlated between the 2 tested years, but most of the grain-filling traits did not show correlation between the 2 years. Correlation analysis revealed that the sink capacity is stable and primarily determines the yield, and grain filling is more affected by the environment. In addition, biomass production before heading and during the maturity stage contributes to higher yield in TD-CSSLs, and the amount of translocation of stem reserve does not affect much to the yield. We conclude that higher NSC at the heading stage and rapid decrease in shoot biomass during the maturity stage did not directly contribute to the yield formation in the japonica genetic background.

Due to the high incidence of mammary tumors in dogs, it is important to elucidate the pathogenesis of these tumors in veterinary medicine. Radiation therapy is often used to treat mammary tumors that target DNA lesions. RAD51 is a key molecule that repairs DNA damage via homologous recombination. We examined the relationship between RAD51 expression and radiosensitivity in mammary tumor cell lines. CHMp and CHMm from the same individual were selected based on the differences in RAD51 expression. The radiosensitivity of both cell lines was examined using MTT and scratch assays; CHMm, which has high RAD51 expression, showed higher sensitivity to radiation than CHMp. However, the nuclear focus of RAD51 during DNA repair was formed normally in CHMp, but not in most of CHMm. Since irradiation resulted in the suppression of cell cycle progression in CHMp, the expression of p21, a cell cycle regulatory factor, was detected in CHMp after 15 Gy irradiation but not in CHMm. These results indicate that functional expression is more important than the quantitative expression of RAD51 in canine mammary tumor cells in response to DNA damage.

We propose a compressed logistic model for bacterial growth by invoking a time-dependent rate instead of the intrinsic growth rate (constant), which was adopted in traditional logistic models. The new model may have a better physiological basis than the traditional ones, and it replicates experimental observations, such as the case example for E. coli, Salmonella, and Staphylococcus aureus . Stochastic colonial growth at a different rate may have a fractal-like nature, which should be an origin of the time-dependent reaction rate. The present model, from a stochastic viewpoint, is approximated as a Gaussian time evolution of bacteria (error function)., (© 2022 IOP Publishing Ltd.)