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The mechanism of PH3 oxidation is investigated at B3LYP/6-311+g (d, p) level using density functional theory calculation with n = 0–6 water molecules addition. The corresponding geometric structure, energy surface profile are studied to determine the catalytic effect of water clusters. The results show that addition of water clusters into the system will be beneficial for the oxidation reaction to different extent. Four water molecules addition is the most favorable mode as it lowers the reaction barrier from 29.04 kcal (0H2O) to 12.40 kcal/mol. The energy barrier follows the order: 0H2O > (H2O)5 > (H2O)2 > (H2O)6 > (H2O)3 > (H2O)4. Natural bond orbital (NBO) analysis shows that four water molecules addition has the largest second order stabilization energy of LP (O1) (O1 in H2O) → σ*(P-H1) and LP (O2) (O2 in H2O) → σ*(O3-H2), which facilitates proton transfer and formation of P-OH bond. In addition, the reaction rate constants k(TS) are simulated from 293 to 433 K. The result shows that four water molecules addition has best catalytic effect thermodynamically and kinetically.

Alzheimer’s disease (AD) is correlated with brain atrophy, neuronal loss, neurotransmitter imbalance, and cognitive decline, which also occur in normal aging. Thus, comparing the differences between normal aging and AD is of interest in order to test the accelerated aging hypothesis of AD. An imbalance between excitatory/inhibitory (E/I) neurotransmission, especially in gamma-aminobutyric acid (GABA) inhibition dysfunction, is involved in both AD and normal aging. In the present study, we performed correlation analyses between electroencephalograms (EEGs) and memory in middle-aged (∼12 months old) wild-type mice (WT) and AD model mice (APP/PS1) after E/I balance adjustment via GABAA agonist muscimol and antagonist bicuculline administration (0.1 mg/kg intraperitoneally). Specifically, EEGs of the hippocampus and prefrontal cortex were recorded during Y-maze performance. Overall, WT and AD mice showed different correlation patterns between EEG activity and behavioral memory performance. Significant correlations were observed in EEG activity across a wider range of frequency bands (2–100 Hz, except 4–8 Hz) in WT mice, but were mainly observed in low frequency bands (delta-theta, 2–8 Hz) in AD mice. In addition, muscimol and bicuculline treatment contributed to better brain function in AD mice; in contrast, bicuculline administration resulted in poorer brain function in WT mice. Thus, our study suggests that AD shows a distinct pattern of disrupted brain function, rather than accelerated aging. Importantly, this work reveals new insights into future AD treatment by influencing low-frequency EEG activity through E/I balance adjustment, thereby aiding cognitive recovery.

Adolescence is a period that exhibits both vulnerability and adaptation to environmental stimulus. This study explored the co-existence effect of environmental enrichment (EE) and restraint stress (RS) on innate anxiety and depressive-like behavior in adolescent mice. Male ICR mice were treated with daily EE and RS (4 h/d or 8 h/d) for 2 or 4 weeks from early adolescence (postnatal day 30) and emotional behaviors were evaluated 24 h after the end of treatment. 4 weeks of 8 h RS treatment decreased immobility time in forced swimming test, demonstrating an antidepressant-like effect. For 2 weeks of treatment, 8 h RS significantly reduced the time spent in the lighted compartment of the light-dark box, indicating an increased anxiety level. These results show that under the present experimental design, RS treatment with different duration could have different effect on mice emotion-related behavior, but there was no interaction between EE and RS.

Background Ischemic stroke leads to a long-term disability in humans and no efficient clinical therapy exists to date. The middle cerebral artery occlusion (MCAO) model in non-human primates has shown to be of value for translational stroke research. New method In the current study, a photothrombotic (PT) stroke model was established in rhesus monkeys with either a proximal or distal segment of middle cerebral artery (MCA) thrombosis. This study is the first that compares the two approaches of PT stroke in monkeys using behavioral and physiological measurements and MRI scans. Results The experiment found that infarct occurred in the MCA target regions, with all monkeys having impaired behavior reflected by deficits in neurologic function, and motor and cognition in object retrieval detour (ORD) task. The monkeys with distal MCA thrombosis developed with sequential photo-irritations of the Sylvian fissure zone, adjacent central anterior gyrus and central posterior gyrus, had similar impairments with respect to behavior and showed a tendency of a small edema volume with proximal MCA thrombosis at days 4 and 7 post PT stroke. Comparison with existing methods The distal MCA thrombosis developed with sequential photo-irritations might provide a consistent and well-tolerated focal ischemia in rhesus monkeys, compared with other PT stroke models which usually were singly conducted on the animal’s motor cortex and had a temporal effect. Conclusions The sequentially photo-irritated PT stroke model is a promising ischemic stroke model in rhesus monkey for studying human stroke pathology and physiology and for new therapies development.

This work explores the adsorption and dissociation of AsH3 on Ni- and Cu-doped graphene by density functional theory (DFT) method. The most stable configurations, adsorption energy, and dissociation pathways are calculated thoroughly. In addition, the electron density difference (EDD), charge transfer, partial density of states (PDOS), and frontier orbitals are performed to describe the adsorption and dissociation process. The first dehydrogenation step on PG-Cu is easier than on PG-Ni due to the lower energy barrier. But further dissociation is becoming difficult in both systems. The third dehydrogenation steps are the rate determining steps for the whole reactions on PG-Ni and PG-Cu, as the energy barrier is 2.01 and 1.72 eV. In conclusion, PG-Ni and PG-Cu has similar AsH3 sensitivity, but the dissociation of AsH3 on PG-Cu is easier than on PG-Ni. It indicates that PG-Cu has better catalytic activity as an AsH3 removal catalyst than PG-Ni. This work may provide useful information for further experimental studies to develop efficient and long-term AsH3 removal catalysts.

This work explores the adsorption and dissociation of AsH

Premise of the Study Microsatellite markers were developed for Primula sinolisteri, a perennial distylous herb belonging to section Obconicolisteri (Primulaceae), to facilitate future investigations of the population genetics and mating patterns of populations in this species. Methods and Results We developed 30 microsatellite markers for P. sinolisteri using HiSeq X‐Ten sequencing and measured polymorphism and genetic diversity in a sample of 36 individuals from three natural populations. The markers displayed relatively high polymorphism, with the number of observed alleles per locus ranging from one to 19 (mean = 4.42). The observed and expected heterozygosity ranged from 0–1.000 and 0.083–0.882, respectively. Twenty‐nine of the loci were also successfully amplified in homostylous P. sinolisteri var. aspera. Conclusions The microsatellite markers we have identified in P. sinolisteri provide powerful tools for investigating patterns of population genetic diversity and the evolutionary relationships between heterostyly and homostyly in this species.

Adolescence is a critical developmental stage during which substantial remodeling occurs in brain areas involved in emotional and learning processes. Although a robust literature on the biological effects of extremely low frequency magnetic fields (ELF-MFs) has been documented, data on the effects of ELF-MF exposure during this period on cognitive functions remain scarce. In this study, early adolescent male mice were exposed from postnatal day (P) 23-35 to a 50 Hz MF at 2 mT for 60 min/day. On P36-45, the potential effects of the MF exposure on spatial memory performance were examined using the Y-maze and Morris water maze tasks. The results showed that the MF exposure did not affect Y-maze performance but improved spatial learning acquisition and memory retention in the water maze task under the present experimental conditions.

The clinical use of morphine to reduce pain is limited because of its drug tolerance, dependence and addiction. In the present study, the tree shrews (Tupaia belangeri chinensis) developed morphine tolerance and chronic morphine dependence by morphine injections with increasing doses (5, 10, 15, 20 mg/kg body weight for 7 days). Meanwhile, the naloxone (1.25 mg/kg body weight)-induced conditioned place aversion (CPA) and the withdrawal symptom were also found. The tree shrew model of chronic morphine dependence can be used to investigate the withdrawal symptoms and to select potential withdrawal symptoms reducing drugs in the future.

Bats (Chiroptera) are the second-most abundant mammalian order in the world, occupying a diverse range of habitats and exhibiting many different life history traits. In order to contribute to this highly underrepresented group we describe the sleep architecture of two species of frugivorous bat, the greater short-nosed fruit bat (Cynopterus sphinx) and the lesser dawn fruit bat (Eonycteris spelaea). Electroencephalogram (EEG) and electromyogram (EMG) data were recorded from multiple individuals (>or=5) by telemetry over a 72-h period in a laboratory setting with light/dark cycles equivalent to those found in the wild. Our results show that over a 24-h period both species spent more time asleep than awake (mean 15 h), less than previous reported for Chiroptera (20 h). C. sphinx spent significantly more of its non-rapid eye movement sleep (NREM) and rapid eye movement sleep (REM) quotas during the light phase, while E. spelaea divided its sleep-wake architecture equally between both light and dark phases. Comparing the sleep patterns of the two species found that C. sphinx had significantly fewer NREM and REM episodes than E. spelaea but each episode lasted for a significantly longer period of time. Potential hypotheses to explain the differences in the sleep architecture of C. sphinx with E. spelaea, including risk of predation and social interaction are discussed.

The beta-adrenergic system has been suggested to be involved in novelty detection and memory modulation. The present study aimed to investigate the role of beta-adrenergic receptors on novelty-based spatial recognition memory and exploratory behavior in mice using Y-maze test and open-field respectively. Mice were injected with three doses of beta-adrenergic receptor antagonist, propranolol (2, 10 and 20 mg/kg) or saline at three different time points (15 min prior to training, immediately after training and 15 min before test). The results showed that higher doses of propranolol (10 and 20 mg/kg) given before the training trial impaired spatial recognition memory while those injected at other two time points did not. A detailed analysis of exploratory behavior in open-field showed that lower dose (2 mg/kg) of propranolol reduced exploratory behavior of mice. Our findings indicate that higher dose of propranolol can impair acquisition of spatial information in the Y-maze without altering locomotion, suggesting that the beta-adrenergic system may be involved in modulating memory processes at the time of learning.

The central nervous system exhibits remarkable plasticity in early life. Prenatal morphine exposure may induce adverse behavioral effects on the neonate and the developing offspring. In the present study, we investigated the effect of prenatal morphine exposure (daily from embryonic days 12-16, 20mg/kg) on 11-day-old chicks using two forms of spatial paradigms: one trial detour behavior task in which animals must bypass an obstacle to reach the desired goal without any training and detour learning task which required several trials of training to reach the detour criterion. The results showed that, on the condition that chicks could successfully detour in the first trial, morphine exposed chicks exhibited longer detour latency to finish the task, coupled by a preference for turning right versus turning left. In contrast, no significant difference in learning and memory was found in detour learning task between morphine exposed chicks and saline chicks. These findings suggest specific behavioral changes associated with prenatal exposure to opioids during mid to late gestation, also raise attention to the possible health hazard from pregnancy drug use in everyday life.

We investigated memory impairment in newly hatched chicks following in ovo exposure to a 50-Hz magnetic field (MF) of 2 mT (60 min/day) on embryonic days 12-18. Isolated and paired chicks were used to test the effect of stress during training, and memory retention was tested at 10, 30, and 120 min, following exposure to a bitter-tasting bead (100% methylanthranilate). Results showed that memory was intact at 10 min in both isolated and paired chicks with or without MF exposure. However, while isolated chicks had good memory retention levels at 30 and 120 min, those exposed to MF did not. The results suggest a potential disruption of memory formation following in ovo exposure to MF, with this effect only evident in the more stressed, isolated chicks.

In the present study, we examined the effects of exposure to an extremely low-frequency magnetic field of 1 mT intensity on learning and memory in Lohmann brown domestic chicks using detour learning task. These results show that 20 h/day exposure to a low-frequency magnetic field induces a significant impairment in detour learning but 50 min/day exposure has no effect.

The central nervous system exhibits remarkable plasticity in early life and can be altered significantly by prenatal morphine exposure. Previous studies show that prenatal morphine exposure may alter the capacity for learning and memory in post-partum chicks. The one-trial passive avoidance learning paradigm with 1-day-old chicks is an excellent model to study several mechanisms of memory formation, including STM, ITM, and LTM. The following represents our investigation of the effect of prenatal morphine exposure on learning and memory deficits in the chick. In these experiments, morphine was injected into the airspace of eggs (20 mg/kg) and the one-trial passive avoidance learning paradigm was used to test the effect of prenatal morphine exposure on memory consolidation. The data suggest that chicks injected with morphine daily from E12 to E16 had significantly impaired long-term memory at 120 min after training (p