Neural representation of a one-week delay in remembering information after production and self-generated elaboration encoding strategy

Many studies have confirmed the memory enhancement effect of production, generation and elaboration which can be effective after only one encoding. It is also known that greater memory enhancement effects can be obtained by combining multiple memory strategies during encoding. This study aimed to investigate whether the combination of production and self-generated elaboration enhances memory performance compared with production or generation alone. A total of 23 undergraduate and graduate students participated in this study. In the functional magnetic resonance imaging analysis, we explored the neural representation of remembering information after production and self-generated elaboration strategy. We set four encoding strategy conditions: (1) Read Silent (read without production), (2) Read Aloud (only production), (3) Add Silent (self-generated elaboration without production), (4) Add Aloud (production and self-generated elaboration). The retrieval performance and brain activity while retrieving the learned sentences after a one-week delay were examined. The behavioral results showed that the highest memory performance was for sentences encoded in Add Aloud. The interaction between production and self-generated elaboration was statistically significant. These results suggest that the memory enhancement effect of combining production and self-generated elaboration is not a simple addition nor synergistic facilitation effect. The imaging results showed that the following areas were related to the retrieval of the target encoded in the add aloud condition: the area related to integration of internal and external information (precuneus), area related to information rich stimuli (lateral occipital lobe), area related to self-involvement and inference of others' feelings (MPFC), area related to seen imagery (retrosplenial region) and area related to adjustment of movement (cerebellum). These results suggest that with an encoding strategy that combines production and self-generated elaboration, integrated auditory input of vocalizations and generated images, visual images of the scene, self-relevance, inference of other's feeling, movement by moving mouth are stored with the target and enhanced memory performance of AA.

Uncertainty drives exploration of negative information across younger and older adults

Although individuals generally avoid negative information, recent research documents that they voluntarily explore negative information to resolve uncertainty. However, it remains unclear (a) whether uncertainty facilitates exploration similarly when exploration is expected to lead to negative, neutral, or positive information, and (b) whether older adults seek negative information to reduce uncertainty like younger adults do. This study addresses the two issues across four experimental studies (N = 407). The results indicate that individuals are more likely to expose themselves to negative information when uncertainty is high. In contrast, when information was expected to be neutral or positive, the uncertainty surrounding it did not significantly alter individuals' exploration behavior. Furthermore, we found that uncertainty increased the exploration of negative information in both older and younger adults. In addition, both younger and older adults chose to explore negative information to reduce uncertainty, even when there were positive or neutral alternatives. In contrast to the age-related similarities in these behavioral measures, older adults demonstrated reduced scores in questionnaires on sensation seeking and curiosity, relative to their counterparts who were younger. These results suggest that information uncertainty has a selective facilitation effect on exploration for negative information and that normal aging does not alter this tendency, despite age-related reductions in self-reported measures of personality traits relevant to information seeking.

Severity Classification of Clinical Signs and Defining the Moribund State as an Experimental Endpoint for Acute Toxicity Testing Using Japanese Medaka (Oryzias latipes)

Use of the moribund state as an endpoint for acute toxicity testing in fish is complicated by the lack of consensus about the sublethal signs that define the state or that can predict imminent death. Defining the moribund state in fish requires determination of the association between each observable sublethal sign and transition to imminent death. To establish a criterion for defining the moribund state in Japanese medaka (Oryzias latipes), we determined death/clinical-sign ratios, defined as the proportion of fish with each clinical sign that transitioned to imminent death, for 13 clinical signs observed in individually housed fish exposed to one of two typical toxicants, three pharmaceuticals, two pesticides, and one metal. Also, the time from onset of each clinical sign to transition to imminent death (referred to as the survival time) was determined by continuous monitoring. Three of the observed clinical signs-immobility, lethargy, and immobility at the surface-were found to be indicators of the moribund state, with each of these signs having a death/clinical-sign ratio of 1.0. Evaluation of the survival time after onset of the other 10 signs enabled determination of whether timely euthanasia would be appropriate, thereby providing a means of reducing the suffering of laboratory fish in the period before death. Environ Toxicol Chem 2022;41:1089-1095. © 2022 SETAC.

The Role of Cognitive Control in Age-Related Changes in Well-Being

Maintaining emotional well-being in late life is crucial for achieving successful and healthy aging. While previous research from Western cultures has documented that emotional well-being improves as individuals get older, previous research provided mixed evidence on the effects of age on well-being in Eastern Asian cultures. However, previous studies in East Asia do not always take into account the effects of cognitive control—an ability which has been considered as a key to enable older adults to regulate their emotions. In the current study, we tested whether cognitive control abilities interact with age in determining individuals’ well-being in 59 Japanese females (age range: 26–79; M_age = 64.95). Participants’ mental health and mental fatigue were tracked for 5 years together with their cognitive control abilities. We found that as individuals became older, they showed improved mental health and decreased mental fatigue. In addition, we found a quadratic effect of age on mental fatigue, which was further qualified by baseline cognitive control abilities. Specifically, in those who had a lower level of cognitive control abilities, mental fatigue declined until the mid-60s, at which point it started increasing (a U-shape effect). In contrast, in those who had a higher level of cognitive control ability, mental fatigue showed a steady decrease with age even after their mid-60s. These results suggest that whether advancing age is associated with positive vs. negative changes in well-being depends on cognitive control abilities, and that preserved cognitive control is a key to maintain well-being in late life.

Proton Shell Evolution below ^{132}Sn: First Measurement of Low-Lying β-Emitting Isomers in ^{123,125}Ag

The β-delayed γ-ray spectroscopy of neutron-rich ^{123,125}Ag isotopes is investigated at the Radioactive Isotope Beam Factory of RIKEN, and the long-predicted 1/2^{-} β-emitting isomers in ^{123,125}Ag are identified for the first time. With the new experimental results, the systematic trend of energy spacing between the lowest 9/2^{+} and 1/2^{-} levels is extended in Ag isotopes up to N=78, providing a clear signal for the reduction of the Z=40 subshell gap in Ag towards N=82. Shell-model calculations with the state-of-the-art V_{MU} plus M3Y spin-orbit interaction give a satisfactory description of the low-lying states in ^{123,125}Ag. The tensor force is found to play a crucial role in the evolution of the size of the Z=40 subshell gap. The observed inversion of the single-particle levels around ^{123}Ag can be well interpreted in terms of the monopole shift of the π1g_{9/2} orbitals mainly caused by the increasing occupation of ν1h_{11/2} orbitals.

Rapid Bactericidal Action of Propolis against Porphyromonas gingivalis

Propolis, a resinous substance produced by bees, is used as a folk medicine for treatment of periodontal diseases. However, its mode of the action and the compounds responsible for its activities remain obscure. In the present study, we comprehensively investigated the antibacterial activities of ethanol-extracted propolis (EEP) and EEP-derived compounds toward Porphyromonas gingivalis, a keystone pathogen for periodontal diseases. Broth microdilution and agar dilution assays were used to determine the minimum inhibitory concentrations of EEP against a range of oral bacterial species, of which P. gingivalis showed a higher level of sensitivity than oral commensals such as streptococci. Its antibacterial activity toward P. gingivalis was maintained even after extensive heat treatment, demonstrating a high level of thermostability. EEP also induced death of P. gingivalis cells by increasing membrane permeability within 30 min. Spatiotemporal analysis based on high-speed atomic force microscopy revealed that EEP immediately triggered development of aberrant membrane blebs, followed by bleb fusion events on the bacterial surface. Furthermore, we isolated artepillin C, baccharin, and ursolic acid from EEP as antibacterial compounds against P. gingivalis. Of those, artepillin C and baccharin showed bacteriostatic activities with membrane blebbing, while ursolic acid showed bactericidal activity with membrane rupture. In particular, ursolic acid demonstrated a greater ability to affect bacterial membrane potential with increased membrane permeability, probably because of its highly lipophilic nature as compared with other compounds. Taken together, these findings provide mechanistic insight into the antibacterial activities of EEP and its exquisite membrane-targeting antibacterial compounds and imply the applicability of narrow-spectrum therapeutics with EEP for treatment of periodontitis. In addition, the advanced technology utilized in the present study to visualize the nanometer-scale dynamics of microorganisms will contribute to expanding our understanding of the activities of antimicrobials and the mechanism of drug resistance in bacteria.

Lysophosphatidic acid in medicinal herbs enhances prostaglandin E2 and protects against indomethacin-induced gastric cell damage in vivo and in vitro

Lysophosphatidic acid (LPA) is a bioactive phospholipid that induces diverse biological responses. Recently, we found that LPA ameliorates NSAIDs-induced gastric ulcer in mice. Here, we quantified LPA in 21 medicinal herbs used for treatment of gastrointestinal (GI) disorders. We found that half of them contained LPA at relatively high levels (40-240 μg/g) compared to soybean seed powder (4.6 μg/g), which we previously identified as an LPA-rich food. The LPA in peony (Paeonia lactiflora) root powder is highly concentrated in the lipid fraction that ameliorates indomethacin-induced gastric ulcer in mice. Synthetic 18:1 LPA, peony root LPA and peony root lipid enhanced prostaglandin E₂ production in a gastric cancer cell line, MKN74 cells that express LPA₂ abundantly. These materials also prevented indomethacin-induced cell death and stimulated the proliferation of MKN74 cells. We found that LPA was present in stomach fluids at 2.4 μM, which is an effective LPA concentration for inducing a cellular response in vitro. These results indicated that LPA is one of the active components of medicinal herbs for the treatment of GI disorder and that orally administered LPA-rich herbs may augment the protective actions of endogenous LPA on gastric mucosa.

β-γ and isomeric decay spectroscopy of 168Dy

This contribution will report on the experimental work on the level structure of 168Dy. The experimental data have been taken as part of the EURICA decay spectroscopy campaign at RIBF, RIKEN in November 2014. In the experiment, a 238U primary beam is accelerated up to 345 MeV/u with an average intensity of 12 pnA. The nuclei of interest are produced by in-flight fission of 238U impinging on Be target with a thickness of 5 mm. The excited states of 168Dy have been populated through the decay from a newly identified isomeric state and via the β decay from 168Tb. In this contribution, scientific motivations, experimental procedure and some preliminary results for this study are presented.

Shell Evolution towards ^{78}Ni: Low-Lying States in ^{77}Cu

The level structure of the neutron-rich ^{77}Cu nucleus is investigated through β-delayed γ-ray spectroscopy at the Radioactive Isotope Beam Factory of the RIKEN Nishina Center. Ions of ^{77}Ni are produced by in-flight fission, separated and identified in the BigRIPS fragment separator, and implanted in the WAS3ABi silicon detector array, surrounded by Ge cluster detectors of the EURICA array. A large number of excited states in ^{77}Cu are identified for the first time by correlating γ rays with the β decay of ^{77}Ni, and a level scheme is constructed by utilizing their coincidence relationships. The good agreement between large-scale Monte Carlo shell model calculations and experimental results allows for the evaluation of the single-particle structure near ^{78}Ni and suggests a single-particle nature for both the 5/2_{1}^{-} and 3/2_{1}^{-} states in ^{77}Cu, leading to doubly magic ^{78}Ni.

Does A Major Earthquake Change Job Preferences and Human Values?

Does a major natural disaster change human values and job preferences? The present studies examined whether the experience of a natural disaster experience shifts people's values and job preferences toward pro–social directions. In Study 1 (cross–temporal analysis), we analysed job application data in nine cities in Japan over 12 years and found that the popularity of pro–social occupations (e.g. firefighter) increased after the Great Hanshin–Awaji Earthquake in 1995, in particular the area hit hardest by the quake. In Study 2 (a large national survey), we found that Japanese respondents who had experienced a major earthquake are more likely to hold a pro–social job than those who never experienced a major earthquake. Together, the current findings suggest that the experience of a major natural disaster shifts human values from the egocentric to the allocentric direction, which in turn could result in a social structure that values pro–social occupations. Copyright © 2017 European Association of Personality Psychology

94 β-Decay Half-Lives of Neutron-Rich _{55}Cs to _{67}Ho: Experimental Feedback and Evaluation of the r-Process Rare-Earth Peak Formation

The β-decay half-lives of 94 neutron-rich nuclei ^{144-151}Cs, ^{146-154}Ba, ^{148-156}La, ^{150-158}Ce, ^{153-160}Pr, ^{156-162}Nd, ^{159-163}Pm, ^{160-166}Sm, ^{161-168}Eu, ^{165-170}Gd, ^{166-172}Tb, ^{169-173}Dy, ^{172-175}Ho, and two isomeric states ^{174m}Er, ^{172m}Dy were measured at the Radioactive Isotope Beam Factory, providing a new experimental basis to test theoretical models. Strikingly large drops of β-decay half-lives are observed at neutron-number N=97 for _{58}Ce, _{59}Pr, _{60}Nd, and _{62}Sm, and N=105 for _{63}Eu, _{64}Gd, _{65}Tb, and _{66}Dy. Features in the data mirror the interplay between pairing effects and microscopic structure. r-process network calculations performed for a range of mass models and astrophysical conditions show that the 57 half-lives measured for the first time play an important role in shaping the abundance pattern of rare-earth elements in the solar system.

Concentrated Phosphatidic Acid in Cereal Brans as Potential Protective Agents against Indomethacin-Induced Stomach Ulcer

One of complications associated with long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) is peptic ulcer. Recently, we found that orally administered phosphatidic acid (PA) ameliorated aspirin-induced stomach lesions in mice. In this study, we identified PA-rich food sources and examined the effects of the food materials on indomethacin-induced stomach ulcer. Among examined, buckwheat (Fagopyrum esculentum) bran contained the highest level of PA (188 mg/100 g). PA was the richest phospholipid (25%) in the lipid fraction of the buckwheat bran. Administration of the lipid extracts of buckwheat bran significantly ameliorated indomethacin-induced stomach lesions in mice. In contrast, wheat (Triticum durum) bran lipids (PA, 4%) and soybean (Glycine max) lipids (PA, 3%) were not associated with ameliorative effects. These results indicated that PA-rich lipids can be used as an effective supplement for prevention of NSAID-induced stomach ulcer.

β-Decay Half-Lives of 110 Neutron-Rich Nuclei across the N=82 Shell Gap: Implications for the Mechanism and Universality of the Astrophysical r Process

The β-decay half-lives of 110 neutron-rich isotopes of the elements from _{37}Rb to _{50}Sn were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r-process calculations and reinforce the notion that the second (A≈130) and the rare-earth-element (A≈160) abundance peaks may result from the freeze-out of an (n,γ)⇄(γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the r process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r-process events.

Isomer decay spectroscopy of 164Sm and 166Gd: midshell collectivity around N=100

Excited states in the N=102 isotones 166Gd and 164Sm have been observed following isomeric decay for the first time at RIBF, RIKEN. The half-lives of the isomeric states have been measured to be 950(60) and 600(140) ns for 166Gd and 164Sm, respectively. Based on the decay patterns and potential energy surface calculations, including β6 deformation, a spin and parity of 6- has been assigned to the isomeric states in both nuclei. Collective observables are discussed in light of the systematics of the region, giving insight into nuclear shape evolution. The decrease in the ground-band energies of 166Gd and 164Sm (N=102) compared to 164Gd and 162Sm (N=100), respectively, presents evidence for the predicted deformed shell closure at N=100.

Yrast 6⁺ seniority isomers of (136,138)Sn

Delayed γ-ray cascades, originating from the decay of (6⁺) isomeric states, in the very neutron-rich, semimagic isotopes (136,138)Sn have been observed following the projectile fission of a ²³⁸U beam at RIBF, RIKEN. The wave functions of these isomeric states are proposed to be predominantly a fully aligned pair of f(7/2) neutrons. Shell-model calculations, performed using a realistic effective interaction, reproduce well the energies of the excited states of these nuclei and the measured transition rates, with the exception of the B(E2;6⁺→4⁺) rate of ¹³⁶Sn, which deviates from a simple seniority scheme. Empirically reducing the νf(7/2)(2) orbit matrix elements produces a 4₁⁺ state with almost equal seniority 2 and 4 components, correctly reproducing the experimental B(E2;6⁺→4⁺) rate of ¹³⁶Sn. These data provide a key benchmark for shell-model interactions far from stability.

Monopole-driven shell evolution below the doubly magic nucleus 132Sn explored with the long-lived isomer in 126Pd

A new isomer with a half-life of 23.0(8) ms has been identified at 2406 keV in (126)Pd and is proposed to have a spin and parity of 10(+) with a maximally aligned configuration comprising two neutron holes in the 1h(11/2) orbit. In addition to an internal-decay branch through a hindered electric octupole transition, β decay from the long-lived isomer was observed to populate excited states at high spins in (126)Ag. The smaller energy difference between the 10(+) and 7(-) isomers in (126)Pd than in the heavier N=80 isotones can be interpreted as being ascribed to the monopole shift of the 1h(11/2) neutron orbit. The effects of the monopole interaction on the evolution of single-neutron energies below (132)Sn are discussed in terms of the central and tensor forces.

β-Decay half-lives of 76,77Co, 79,80Ni, and 81Cu: experimental indication of a doubly magic 78Ni

The half-lives of 20 neutron-rich nuclei with Z=27-30 have been measured at the RIBF, including five new half-lives of (76)Co(21.7(-4.9)(+6.5) ms), (77)Co(13.0(-4.3)(+7.2) ms), (79)Ni(43.0(-7.5)(+8.6) ms), (80)Ni(23.9(-17.2)(+26.0) ms), and (81)Cu(73.2 ± 6.8 ms). In addition, the half-lives of (73-75)Co, (74-78)Ni, (78-80)Cu, and (80-82)Zn were determined with higher precision than previous works. Based on these new results, a systematic study of the β-decay half-lives has been carried out, which suggests a sizable magicity for both the proton number Z = 28 and the neutron number N=50 in (78)Ni.

1p3/2 proton-hole state in 132Sn and the shell structure along N = 82

A low-lying state in 131In82, the one-proton hole nucleus with respect to double magic 132Sn, was observed by its γ decay to the Iπ=1/2- β-emitting isomer. We identify the new state at an excitation energy of Ex=1353  keV, which was populated both in the β decay of 131Cd83 and after β-delayed neutron emission from 132Cd84, as the previously unknown πp3/2 single-hole state with respect to the 132Sn core. Exploiting this crucial new experimental information, shell-model calculations were performed to study the structure of experimentally inaccessible N=82 isotones below 132Sn. The results evidence a surprising absence of proton subshell closures along the chain of N=82 isotones. The consequences of this finding for the evolution of the N=82 shell gap along the r-process path are discussed.

Isomers in 128Pd and 126Pd: evidence for a robust shell closure at the neutron magic number 82 in exotic palladium isotopes

The level structures of the very neutron-rich nuclei 128Pd and 126Pd have been investigated for the first time. In the r-process waiting-point nucleus 128Pd, a new isomer with a half-life of 5.8(8) μs is proposed to have a spin and parity of 8(+) and is associated with a maximally aligned configuration arising from the g(9/2) proton subshell with seniority υ=2. For 126Pd, two new isomers have been identified with half-lives of 0.33(4) and 0.44(3) μs. The yrast 2(+) energy is much higher in 128Pd than in 126Pd, while the level sequence below the 8(+) isomer in 128Pd is similar to that in the N=82 isotone 130Cd. The electric quadrupole transition that depopulates the 8(+) isomer in 128Pd is more hindered than the corresponding transition in 130Cd, as expected in the seniority scheme for a semimagic, spherical nucleus. These experimental findings indicate that the shell closure at the neutron number N=82 is fairly robust in the neutron-rich Pd isotopes.

Antitumor properties and modulation of antioxidant enzymes' activity by Aloe vera leaf active principles isolated via supercritical carbon dioxide extraction

The aim of this study was to evaluate the potential anticancer properties and modulatory effect of selected Aloe vera (A. vera) active principles on antioxidant enzyme activities. Thus, three anthraquinones (Namely: aloesin, aloe-emodin and barbaloin) were extracted from A. vera leaves by supercritical fluid extraction and subsequently purified by high performance liquid chromatography. Additionally, the N-terminal octapeptide derived from verectin, a biologically active 14 kDa glycoprotein present in A. vera, was also tested. In vivo, active principles exhibited significant prolongation of the life span of tumor-transplanted animals in the following order: barbaloin> octapeptide> aloesin > aloe-emodin. A. vera active principles exhibited significant inhibition on Ehrlich ascite carcinoma cell (EACC) number, when compared to positive control group, in the following order: barbaloin> aloe-emodin > octapeptide > aloesin. Moreover, in trypan blue cell viability assay, active principles showed a significant concentration-dependent cytotoxicity against acute myeloid leukemia (AML) and acute lymphocytes leukemia (ALL) cancerous cells. Furthermore, in MTT cell viability test, aloe-emodin was found to be active against two human colon cancer cell lines (i.e. DLD-1 and HT2), with IC(50) values of 8.94 and 10.78 microM, respectively. Treatments of human AML leukemic cells with active principles (100 microg ml(-1)) resulted in varying intensities of internucleosomal DNA fragmentation, hallmark of cells undergoing apoptosis, in the following order: aloe-emodin> aloesin> barbaloin> octapeptide. Intererstingly, treatment of EACC tumors with active principles resulted in a significant elevation activity of key antioxidant enzymes (SOD, GST, tGPx, and LDH). Our data suggest that the tested A. vera compounds may exert their chemo-preventive effect through modulating antioxidant and detoxification enzyme activity levels, as they are one of the indicators of tumorigenesis. These findings are discussed in the light of the potential of A. vera plant extracts for developing efficient, specific and non-toxic anticancer drugs that are affordable for developing countries.

Fast-scanning atomic force microscopy reveals the molecular mechanism of DNA cleavage by ApaI endonuclease

Newly developed fast-scanning atomic force microscopy (AFM) allows the dissection of molecular events such as DNA-enzyme reactions at the single-molecule level. With this novel technology, a model is proposed of the DNA cleavage reaction by a type IIP restriction endonuclease ApaI. Detailed analyses revealed that ApaI bound to DNA as a dimer and slid along DNA in a one-dimensional diffusion manner. When it encountered a specific DNA sequence, the enzyme halted for a moment to digest the DNA. Immediately after digestion, the ApaI dimer separated into two monomers, each of which remained on the DNA end and then dissociated from the DNA end. Thus, fast-scanning AFM is a powerful tool to aid the understanding of protein structures and dynamics in biological reactions at the single-molecule level in sub-seconds.