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The TBC (thermal barrier coating) systems provide protection against high temperature corrosion of the superalloy substrates in the gas turbine engines. However, the lateral growth of TGO (thermally-grown oxide) and the thermal expansion misfit between TGO and BC(bond coat) induce internal stress which can be sufficient to activate plastic deformation or buckling in TGO. In this paper, the analytic and optimization methods were applied for improving durability of the TBC system. First, an analytic method for obtaining the deformation results of TBC system was applied. In the following step, the analysis results were obtained for the experimental points selected by the D-optimal DOE method. Based on these analysis data, the fitting functions for showing the deformation of the TBC system were constructed using the response surface method. Finally, a multi-objective global optimization method was developed for upgrading durability of the TBC system. The developed analytic and optimization methods can be widely used to improve the performance of the TBC system for the gas turbine engines.

The theoretical positioning accuracy of multilateration (MLAT) with the time difference of arrival (TDOA) algorithm is very high. However, there are some problems in practical applications. Here we analyze the location performance of the time sum of arrival (TSOA) algorithm from the root mean square error (RMSE) and geometric dilution of precision (GDOP) in additive white Gaussian noise (AWGN) environment. The TSOA localization model is constructed. Using it, the distribution of location ambiguity region is presented with 4-base stations. And then, the location performance analysis is started from the 4-base stations with calculating the RMSE and GDOP variation. Subsequently, when the location parameters are changed in number of base stations, base station layout and so on, the performance changing patterns of the TSOA location algorithm are shown. So, the TSOA location characteristics and performance are revealed. From the RMSE and GDOP state changing trend, the anti-noise performance and robustness of the TSOA localization algorithm are proved. The TSOA anti-noise performance will be used for reducing the blind-zone and the false location rate of MLAT systems.

Like mothers, fathers play a vital role in the development of the brain and behavior of offspring in mammals with biparental care. Unlike mothers, fathers do not experience the physiological processes of pregnancy, parturition, or lactation before their first contact with offspring. Whether pup exposure can induce the onset of paternal behavior and the underlying neural mechanisms remains unclear. By using Slc:ICR male mice exhibiting maternal-like parental care, the present study found that repeated exposure to pups for six days significantly increased the total duration of paternal behavior and shortened the latency to retrieve and care for pups. Repeated pup exposure increased c-Fos-positive neurons and the levels of dopamine- and TH-positive neurons in the nucleus accumbens (NAc). In addition, inhibition of dopamine projections from the ventral tegmental area to the NAc using chemogenetic methods reduced paternal care induced by repeated pup exposure. In conclusion, paternal behavior in virgin male ICR mice can be initiated by repeated pup exposure via sensitization, and the dopamine system may be involved in this process.

Consolation is a complex empathic behavior that has recently been observed in some socially living rodents. Despite the growing body of literature suggesting that stress affects some simple form of empathy, the relationship between stress and consolation remains largely understudied. Using monogamous mandarin voles, we found that an acute restraint stress exposure significantly reduced consolation-like behaviors and induced anxiety-like behaviors. Along with these behavioral changes, corticotropin-releasing factor (CRF) and CRF receptor 1 (CRFR1) neurons were activated within the anterior cingulate cortex (ACC) and prelimbic cortex (PrL) but not within the infralimbic cortex (IL). Chemogenetic activation of CRF neurons in the ACC and PrL, recaptured acute stress-induced behavioral dysfunctions. We further observed that intracellular PKA and PKC signaling pathways mediate CRF-induced behavioral dysfunctions, but they work in a regional-specific, sex-biased manner. Together, these results suggest that the local CRF-CRFR1 system within the ACC and PrL is involved in the consolation deficits and anxiety induced by acute stress.

In the early stage of life, experiencing social isolation can generate long-lasting deleterious effects on behaviors and brain development. However, the effects of chronic social isolation during adolescence on social behaviors and its underlying neurobiological mechanisms remain unclear. The present study found that four weeks of social isolation during adolescence impaired social recognition ability in the three-chamber test and five-trial social recognition test, and increased aggressive-like behaviors, but reduced environmental exploration, as showed in the social interaction test. Chronic social isolation decreased levels of dopamine D2 receptor in the shell of the nucleus accumbens (NAcc) and medial prefrontal cortex. It also reduced TH in the NAcc. Using in vivo fiber photometry, it was also found that isolated mice displayed a reduction in NAcc shell activity upon exploring unfamiliar social stimuli. An injection of a 100 ng dose of the D2R agonist quinpirole into the shell of the NAcc reversed behavioral abnormalities induced by chronic social isolation. These data suggest that the dopamine system is involved in alterations in social behaviors induced by chronic social isolation. This finding sheds light on the mechanism underlying abnormalities in social behavior induced by adolescent chronic social isolation and provides a promising target to treat mental diseases relevant to social isolation.

Chronic social defeat stress (CSDS) has been found to produce different impacts on anxiety-like behaviors, spatial cognitive function and memory in rodents with different susceptibilities. However, the impacts of chronic social defeat on social behaviors in adult male mice with different susceptibilities to social defeat and the underlying mechanisms in the brain remain unclear. In the present study, we found that ten days of social defeat reduced the tendency of susceptible adult male C57 mice to approach an unfamiliar individual and increased their avoidance of an unfamiliar CD-1 mouse but had no effects on resilient individuals. In addition, CSDS enhanced anxiety-like behavior in susceptible animals, but produced no effects in the resilient group. Meanwhile, CSDS increased the number of corticotropin-releasing factor (CRF)-positive neurons in the paraventricular nucleus of the hypothalamus and CRF-R2-positive neurons in the accumbens nucleus shell in both resilient and susceptible animals. CSDS increased the number of CRF-R1-positive neurons and CRF-R1 mRNA expression in the prelimbic cortex (PrL) and the number of CRF-R2-positive neurons in the basolateral amygdala, but reduced the number of CRF-R2-positive neurons and mRNA expression in the PrL in susceptible animals. Therefore, the different effects of CSDS on sociability and anxiety-like behavior in mice with different susceptibilities may be associated with region- and type-specific alterations in CRF receptor levels. These findings help us understand the underlying mechanism by which social stress affects emotion and social behavior and provides an important basis for the treatment of disorders of social and emotional behavior caused by social stress.

Reaction between silver salt and conjugational N-hetrocyclic carboxylic acid with the presence of bipyridyl skeletons auxiliary ligand afforded a d10 metal polymer namely [(ddpp)Ag(bipy) (1)] (ddpp = 2, 5-di(2′,4′-dicarboxylphenyl)pyridine, bipy = 4,4′-bipyridine). It was characterized by elements analysis, infrared spectroscopy, single crystal X-ray diffraction and thermogravimetry studying. For the polymer 1, silver centers are three coordinated geometry with an ON2 donor set provided by ddpp and bipy. The polymer 1 is built from 1-D alternative/zig-zag chain, as the secondary building unit, and further stacks via hydrogen bonds which formed between two isophthalic moieties of ddpp ligands and weak interactions to generate a two-dimensional, 2D supramolecular layer. Moreover, the polymer 1 displays thermal stability in solid state and the luminescence behaviour is also investigated in a dimethyl sulphoxide solution at ambient temperature, and it also can be applied in design of sensors to detect of trace aluminum, zinc and calcium ion.

Feature extraction of radar echo image is an important part of identification and recognition of air targets. In recent years, with the rapid development of deep learning, new solutions are provided for it. In this paper, the convolution neural network (CNN) is applied to feature extraction. Based on the classic CNN model, Adam is used to update the model parameters, dropout is used to prevent over fitting, and an improved CNN model is constructed. Then, the radar echo image data set is used to train the model, so as to extract target features and classify them. Simulation results show that the accuracy of the improved model is 99%, and the training speed is greatly improved. Different from the traditional extraction method which relies on manual experience, the improved CNN can improve the efficiency of feature extraction of radar echo image and lay a solid foundation for further research and identification of air targets.