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To explore the size effect of asphalt mixture, asphalt mastic asphalt mixture was taken as the research object, and the uniaxial compressive strength was used as the evaluation index. The applicability of the three size effect theories of Bazant, Carpinteri, and Weibull were evaluated, and the corresponding size effect law parameters were calculated. The critical dimensions and critical strength of the asphalt mixture were determined, and the effects of coarse aggregate properties, maximum nominal particle size, and loading rate on the size effect of asphalt mixture were analyzed. Results show that the asphalt mixture has an obvious size effect phenomenon, and the uniaxial compressive stress-strain curves of asphalt samples with different sizes have the characteristics of compaction stage, elastic stage, and transition from plastic deformation to failure stage. The uniaxial compressive strength of the asphalt mixture is negatively correlated with the sample size, and as the sample size increases, the strength reduction decreases gradually. With the increase in the elastic modulus of the coarse aggregate, the critical strength value increases continuously, and the critical dimension decreases. As the maximum nominal particle size increases, the critical dimension and critical strength increase gradually. With the increase in the loading rate, the critical strength continues to increase, and the critical dimension gradually decreases. The Bazant and Carpinteri size effect laws are more suitable for the analysis of the size effect of asphalt mixture, while the Weibull size effect law has a large error. When SMA is used as the pavement structural layer, the ratio S of the structural layer thickness to the maximum nominal particle size calculated by the Bazant size effect law is 2.6 to 3.5, and the S range calculated by the Carpinteri size effect law is 2.6 to 4.0.

Juvenile social isolation (SI) and neglect have a negative impact on neurodevelopment persistently, which is associated with cognitive dysfunction in neurodevelopmental disorders. Given the critical role of metabotropic glutamate receptors (mGluRs) in synaptic homeostasis of the prefrontal cortex (PFC), pharmacological intervention on mGluRs has been attempted in order to improve cognitive dysfunction in animal models of neurodevelopmental disorder, as well as in clinical trials. Here we examined the effects of the mGluR2/3 antagonist LY341495 on prefrontal synaptic transmission, spatial working memory, and recognition memory in adult C57BL/6J mice that experienced juvenile SI. We found that SI-reared mice exhibited working memory impairment and decreased excitatory presynaptic release probability of pyramidal neurons in the medial PFC compared with group-reared mice. The positive effect of LY341495 on excitatory synaptic transmission in SI-reared mice was more prominent than the effect in group-reared mice. A single treatment with mGluR2/3 antagonist LY341495 significantly improved the performance of SI-reared mice in the Y-maze test but not in the novel object recognition (NOR) test, while repeated treatments were effective in both tasks. These findings suggest that enhancing glutamatergic transmission via inhibition of mGluR2/3 signaling might represent a promising strategy for improving cognitive function in neurodevelopmental disorders.

SUMMARY: The myodural bridge (MDB) is confirmed that connecting the most of suboccipital muscles to the cervical dura mater through the posterior intervertebral spaces and widely exists in mammals and birds. In order to reveal whether the MDB is universally existing in amniota of vertebrates, we explored the existence and the morphological features of the MDB in the Trachemys scripta elegans. Twenty fresh red-eared slider specimens were observed by the gross anatomy dissection and histological analysis. In the results, three kind of muscles in the postoccipital region of the red-eared slider were found. The rectus capitis dorsum minor muscle originated from the posterior margin of the occiput (C0) and terminated at the spinous process of the atlas (C1). The transversospinales muscle was attached to the vertebral arch and the postzygapophysis of the atlas and extended to the spinous process of the axis (C2). The C2-C3 intertransversales muscle were extended from the postzygapophysis of C2 and the one of C3. The three muscles covered the dorsal interspaces among C0-C3, and meantime they were closely connected with dense connective tissues, which filled in these interspaces. Each of these thick dense connective tissue membranes sent off several short and strong fibrous bundles ventrally to merge with the cervical spinal dura mater. Furthermore the connective tissues connecting these muscles with cervical spinal dura mater directly were revealed under the microscopy and they consisted of parallel and intensive collagen fibers with orientation from dorsal to ventral. In conclusion, this study for the first time demonstrated the existence of the MDB in the testudines, in all of the dorsal atlantooccipital, atlantoaxial and C2-C3 intervertebral spaces. Based on our results and comparative anatomical evidences in recent year, it could be inferred that the MDB might be its highly conserved structure in the evolution of amniota.

The experimental optical rotation (OR), electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) spectra of (R)-3-hydroxy-4,5-dimethylfuran-2(5H)-one (sotolon, 1) and (R)-5-ethyl-3-hydroxy-4-methylfuran-2(5H)-one (maple furanone, 2) taken in chloroform were compared to their spectra calculated with time-dependent density functional theory (TDDFT). Sotolon was shown to exist as a dimer in chloroform while maple furanone remains a monomer. Transition state barriers for the enol/keto tautomerization of sotolon were calculated and found to be high. The VCD method offers promise to ultimately distinguish between the presence of monomers or dimers.

Juvenile social isolation (SI) and neglect is associated with a wide range of psychiatric disorders. While dysfunction of the corticolimbic pathway is considered to link various abnormal behaviors in SI models of schizophrenia, the enduring effects of early social deprivation on physiological properties of medium spiny neurons (MSNs) in nucleus accumbens (NAc) are not well understood. This study investigated the impacts of juvenile SI on locomotor activity to methamphetamine (METH) and neurophysiological characteristics of MSNs in the core of NAc. Socially isolated C57BL/6 mice experienced single housing for 4 weeks on postnatal day (PND) 21. The locomotor response to METH (1.0 mg/kg) was observed in both socially isolated and group-housed mice at PND 56. The effects of juvenile SI on the excitatory synaptic events in MSNs and the intrinsic excitability of MSNs in NAc core were investigated in other batches during PND 63–70. Socially isolated mice showed locomotor hypersensitivity to METH, although the expression of locomotor sensitization to METH in socially isolated mice was not different from group-housed mice. The recordings from MSNs of SI-reared mice exhibited higher frequency and smaller amplitude of miniature/spontaneous excitatory postsynaptic current than those from group-reared mice. Moreover, SI resulted in increased intrinsic excitability of MSNs in adult mice. These results demonstrate neuronal hyperactivity in the NAc of socially isolated mice, which could contribute to locomotor hypersensitivity to METH. Furthermore, the findings indicate a biological link between early negative life events and the vulnerability to psychostimulant-induced psychosis in adulthood.

This study constructed the relationship between l -amino acids and four-carbon d -sugar using quantum theory. Theoretically, an l -amino acid could react with the ketone to afford the corresponding Schiff base which may take place an Aldol reaction with a molecule of formaldehyde. An assumption is proposed that the Aldol addition products with ( R ) or ( S ) configuration could have different quantity due to the effect from stereogenic center of l -amino acid. By hydrolysis of the Aldol addition, different d - or l -sugar would form. Thus, B3LYP, WP1MPW91 and wB97XD theories were used for the energy difference computations at the 6-311++G(2d,p) level in the gas phase, or in water using PCM and SMD model, respectively. The predicted ee value sequence agrees well to the experimental result in the asymmetric synthesis of 3-carbon sugar using five l -amino acids. Further theoretical study exhibited that 4-carbon D sugar should form if the corresponding l -amino acid is used. The ee values of the 4-carbon sugar are bigger than those of 3-carbon d -sugars catalyzed by the same l -amino acids. This looks like the chiral amplification in the procedure.

Binocular depth perception (BDP) is one of the most demanding visual function that involves both dorsal and ventral visual information streams. Substantial research has been conducted on the disruption of BDP in patients with schizophrenia. However, research on first-episode and drug-naive patients with schizophrenia (FEDN) is limited. To assess the BDP of schizophrenia patients while controlling for the effects of antipsychotics and the duration of illness. We investigated BDP in patients with schizophrenia via the Titmus Stereopsis Test in this study, by matching the patients into three groups: FEDN (n = 17), long duration of illness and medicine treatment (LDMT) (n = 31) and the healthy control group (n = 40). Results showed that both the FEDN (mean = 1.71, 95% confidence interval [CI]: [1.57, 1.84]) and LDMT (1.73, 95% CI: [1.66, 1.81]) patients displayed a significant decline (p = 0.01, Cohen's d = 0.67, p = 0.001, Cohen's d = 0.92, respectively) in depth perception compared to the healthy control (1.55, 95% CI: [1.48, 1.61]) group. Additionally, there were no significant differences (p = 0.68, Cohen's d = 0.11) between the FEDN and LDMT groups, and no correlation (Pearson r = -0.16, p = 0.38, R2 = 0.03) was observed between the duration of illness and impaired BDP in the LDMT group. The proportion of individuals with stereopsis detection in either FEDN (12/17) or LDMT (26/31) groups under stereo threshold 63 arc seconds (″), were significantly lower (Pearson χ2 = 6.29, p = 0.043, φc = 0.27) compared to the healthy control group (38/40). Significant difference in stereopsis detection also occurred at 50″ (Pearson χ2 = 12.31, p = 0.001, φc = 0.37), 40″ (Pearson χ2 = 12.38, p = 0.002, φc = 0.38), 32″ (Pearson χ2 = 6.69, p = 0.035, φc = 0.28), 25″ (Pearson χ2 = 14.82, p = 0.001, φc = 0.41) and 20″ (Pearson χ2 = 6.73, p = 0.034, φc = 0.28) between the three groups. These findings showed a moderately strong association between schizophrenia and defective stereopsis.

A novel driving method implemented with high frequency electromagnetic isolation is proposed in this paper. And the hardware designing schematic diagram and the software configuration method are presented. Then the corresponding operating principle is analyzed in detail based on digital control chip and analog circuits. The proposed driving method can be applied to real-time varying pulse width of the control signal and the duty-cycle ratio of this control pulse can be regulated in the range of 0–100 %. This novel driving method can achieve not only the advantages of high insulation and high common-mode suppression, but also the merits of low cost and fast dynamic response speed, and it is suitable for the isolation and amplification of high frequency switching control pulse signal. Finally, the experimental results show that the proposed driving method in this paper is effective.

In this study, the effects of siderophores produced by six bacteria on mycelium growth, Cd and Pb accumulation, lipid peroxidation, protein content and antioxidant enzyme in Oudemansiella radicata were investigated in Cd and Pb-containing liquid medium. The results showed that inoculation with siderophore-containing filtrates (SCF) partly enhanced the growth of O. radicata after 15 days, with 0.8-32.4% biomass increase for Cd and 0.7-20.8% for Pb compared to control(s), which lacked siderophore. The maximum enhancement for accumulation were found to be confined to Bacillus sp. FFQ2(s) (26.5%) for Cd and Pseudomonas sp. CY63(s) (158.9%) for Pb. A significant decrease in MDA content indicated that lipid peroxidation in O. radicata was alleviated by siderophores. Besides, antioxidant enzyme SOD and POD activities also displayed obviously decrease in SCF-treated mycelium compared to control(s) treatment, while CAT activity did not present significant change. Protein level in O. radicata treated by SCF increased from 0.3 to 138.0% for Cd and from 10.9 to 107.1% for Pb compared to control(s). Therefore, the present work suggests that microbial siderophores can reduce the toxicity of metals to mycelium and then alleviate heavy metals-inducing oxidative stress in O. radicata.

In the last two decades, many studies have focused on the muscles and dense connective tissues located in the suboccipital region. Our study investigated the existence of the second terminations originating from the suboccipital muscles, and the relationship between the variable types of the To Be Named Ligament (TBNL). Anatomical dissection was performed on 35 head-neck specimens. The existence of the second terminations of the suboccipital muscles was confirmed and various types of the TBNL were observed in this study. The second terminations originated from multiple suboccipital muscles including the rectus capitis posterior minor (RCPmi), rectus capitis posterior major (RCPma) and obliquus capitis inferior (OCI) muscles, merged and terminated at the TBNL. The overall incidence of the second terminations of the suboccipital muscles was 34.29% and it varied among the various suboccipital muscle origins. 28.57% of the second terminations originated from the RCPma; 11.43% was from the RCPmi and 8.57% was from the OCI. Furthermore, there was a significant relationship between the existence of second terminations and the particular type of the TBNL. 95% of the arcuate type of the TBNL was accompanied with the second terminations which attached to their turning part, whereas only 10% of all the radiate type of the TBNL was accompanied with the second terminations. This study for the first time described the second terminations originating from multiple suboccipital muscles and demonstrated the relationship with the various types of the TBNL. We speculated that the second terminations maintain the arcuate TBNL and transfer tensile forces to the Myodural Bridge (MDB), thereby modulating the physiological functions of the MDB.