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ObjectiveTo analyze and assess the pollution levels of lead (Pb), cadmium (Cd), and chromium (Cr) in rural soils of Wanzhou District, Chongqing Municipality, and to provide data support for proposing relevant measures and suggestions.MethodsBased on the soil monitoring data from 2017 to 2021, the ecological risk assessment was conducted by applying the Soil Pollution Risk Control Standard for Agricultural Land of Soil Environmental Quality (for trial implementation) (GB 15168‒2018), the pollution index method and the potential ecological risk method.ResultsA total of 100 soil samples were collected, with pH values ranged from 3.50 to 8.30, and a mean value of 6.10. The mean values of Pb, Cd, and Cr in the soil were 25.2 mg·kg-1, 0.310 mg·kg-1, and 68.6 mg·kg-1, respectively. Except for Cr, the mean values of other elements exceeded the soil background values. Cd level had the largest coefficient of variation and uneven spatial distribution, with an overall exceedance rate of 30.0%. Pollution levels of Pb and Cr were generally at the alert level, while Cd was generally at a light pollution level. The proportion of Cd pollution levels was higher than that of Pb and Cr, and the difference was statistically significant (χ2=15.015, P=0.001). The Nemerow comprehensive pollution index in different townships ranged from 0.70 to 2.07, with a median value of 1.10, and was generally at a light pollution level. The potential ecological hazard risk of Cd was relatively high, and was generally at a mild level of hazard. The highest contribution rate in the comprehensive potential ecological hazard index was Cd, accounting for 84.1%.ConclusionThere is a certain degree of Cd pollution and mild ecological risk in rural soils of Wanzhou District. Monitoring and management of Cd pollution in rural soils of Wanzhou District, Chongqing Municipality, should be strengthened.

Against the background of the new phase of urban-rural integration and development in China, the importance of the translocal mindset has been increasingly highlighted. It has also been found that factors such as urban-rural factor flow, structural adjustment, and functional transformation have a series of effects on household livelihood resilience. Therefore, identifying rural-urban translocal household livelihood resilience characteristics and exploring the rural-urban population impact influx on rural household livelihood resilience are important guidelines for the formulation and implementation of policies related to new urbanization, regional agriculture, and rural areas. This study conducted in-depth field research in six villages spanning four counties and districts in Lishui City to identify the key characteristics of translocal households. It constructed an indicator system encompassing buffering capacity, self-organization, and learning ability, employed advanced mathematical methods such as the entropy method, comprehensive index method, and structural equation modeling to quantitatively measure the livelihood resilience of translocal families, and analyzed the characteristics of different types of translocal households' livelihood resilience in different regions and the influencing factors of translocal households' livelihood resilience in the context of population mobility. In addition, this study examined the most recent and pre-eminent scholarly works, profoundly incorporating their insights. This approach not only enhances the theoretical lens for examining the resilience of urban-rural cross-regional household livelihoods, but also provides a rigorous scientific basis for policy formulation. These authoritative references, characterized by their theoretical sophistication and empirical robustness, serve as a crucial source of inspiration and validation for this research, thereby assuming paramount significance in guiding the advancement of new urbanization and urban-rural integration. Based on the aforementioned study background, research methodology, and cited authoritative literature, this study drew the following conclusions: 1) Urban cross-locality significantly enhances the resilience level of rural families with poor transportation conditions and average economic development. However, for rural areas with better overall development, the impact of such rural-urban population migration is limited. The overall level of livelihood resilience of rural-urban cross-regional families in Lishui is moderate, with a mean score of 0.304, which is significantly higher than the mean value of 0.245 for non-cross-regional rural families. This difference is mainly reflected in the learning abilities of the family members. 2) The key to rural-urban cross-locality migration lies in the information flow transmitted by family members after migration. This greatly enhances the knowledge and information environment of the family, further increasing their livelihood resilience by optimizing their learning ability. The improvement in the information environment obtained through population migration has a greater impact on the family livelihood resilience level than capital flow, whereas material flow has no significant impact. 3) In addition to information flow, factors such as "proportion of migrant workers," "education level of migrant workers," "occupational stability of migrant workers," "number of vocational training times for migrant workers," and "income proportion of migrant workers" are also key factors affecting the livelihood resilience of cross-locality families. 4) The impact of population flow characteristics on resilience is the most significant, followed by information flow characteristics; furthermore, capital flow's impact is relatively low. However, there is no significant correlation between material flow characteristics and level of resilience of cross-regional family livelihoods. Besides strengthening their own capabilities, migrant workers conveying ideas and information about new technologies in the city to rural families is also an important factor improving the level of resilience in family livelihoods.

The diblock copolymer electrolyte PEGMEMAm-GMAn-Br （PGA-Br）， a copolymer of poly（ethylene glycol methyl ether methacrylate） （PEGMEMA）， and glycidyl methacrylate （GMA） were synthesised by designing the molecular structure of the polymer and using thermally-initiated free-radical polymerisation. The electrochemical performance were investigated. The results show that the ionic conductivity of polymer electrolyte is improved by PGA block or grafting on polymer electrolyte， and the ionic conductivity at room temperature reaches 1.05×10-4 S·cm-1. At the same time， PGA-Br block copolymer electrolytes exhibit a low glass transition temperature （-65 ℃）， a high thermal decomposition temperature， an electrochemical stability window of up to 5.1 V， and flame-retardant property. The Li|Li symmetrical solid-state battery assembled with PGA-Br copolymer electrolyte exhibits an enhanced electrode/electrolyte solid-solid interface， which can achieve uniform deposition of lithium metal and effectively inhibit the lithium dendrites growth. The LiNi0.8Co0.1Mn0.1O2 （NCM811） |PGA-Br|Li solid-state battery based on PGA-Br block copolymer electrolyte can achieve a high first cycle discharge specific capacity of 160.1 mAh/g at 0.1 C， and the capacity retention rate is as high as 91.5% after 100 cycles， and with a stable Coulombic efficiency of over 98.5%.

Abstract Parkinson’s disease (PD) is the second largest group of neurodegenerative diseases, and its existing drug treatments are not satisfactory. Natural cell membrane drugs are used for homologous targeting to enhance efficacy. In this study, microfluidic electroporation chip prepared mesenchymal stem cell-derived neuron-like cell membrane-coated curcumin PLGA nanoparticles (MM-Cur-NPs) was synthesized and explored therapeutic effect and mechanism in PD. MM-Cur-NPs can protect neuron from damage, restore mitochondrial membrane potential and reduce oxidative stress in vitro. In PD mice, it also can improve movement disorders and restore damaged TH neurons. MM-Cur-NPs was found to be distributed in the brain and metabolized with a delay within 24 h. After 1 h administration, MM-Cur-NPs were distributed in brain with a variety of neurotransmitters were significantly upregulated, such as dopamine. Differentially expressed genes of RNA-seq were enriched in the inflammation regulation, and it was found the up-expression of anti-inflammatory factors and inhibited pro-inflammatory factors in PD. Mechanically, MM-Cur-NPs can not only reduce neuronal apoptosis, inhibit the microglial marker IBA-1 and inflammation, but also upregulate expression of neuronal mitochondrial protein VDAC1 and restore mitochondrial membrane potential. This study proposes a therapeutic strategy provide neuroprotective effects through MM-Cur-NPs therapy for PD.

With the deepening application of artificial intelligence in the field of education, teaching quality evaluation has become the key to improving educational effectiveness. In order to quantify the effectiveness of knowledge transmission and mastery in digital media teaching, this paper proposes an improved Bayesian knowledge tracking model (BF-BKT), which has been specifically optimized for teaching quality evaluation. The motivation stems from the shortcomings of existing technology in evaluating teaching quality, especially the lack of effective integration of student learning behavior and forgetting patterns. This article describes the development process of the BF-BKT model, which innovatively combines learning behavior data and forgetting patterns by introducing behavioral forgetting features to more accurately predict students’ learning status and teaching effectiveness. The BF-BKT model not only considers whether students have mastered a certain knowledge point, but also further analyzes their forgetting situation at different time points, providing a more comprehensive perspective for evaluating teaching quality. To validate the performance of the BF-BKT model, we compared it with the traditional BKT model and two diverse BKT variants. We conducted systematic experiments and analysis by selecting public datasets as simulation scenarios. The experimental results show that the BF-BKT model performs well in predicting students’ knowledge mastery and evaluating teaching quality, and its performance is superior to other comparative methods, proving the effectiveness and superiority of the model.

Abstract Background One noteworthy concern within the realm of education is the level of engagement demonstrated by students. Among the factor that can have a crucial role in this domain is teacher support, especially emotional support which has an impact on several aspects of learners’ education. Furthermore, various studies have investigated the relationship between Emotional Intelligence (EI) and learners’ engagement. Methods Accordingly, this study investigated the possible role of trait EI and the emotional support of teachers and how these constructs may work to associate learners’ engagement. For this objective, a total of 309 Chinese students across different colleges and universities in 5 provinces of Beijing, Shanghai, Jiangsu, Hubei, and Shaanxi were enrolled. They were 126 females and 183 males, with ages ranging from 18 to 30 years old (Mean = 24.6). Results The results of this research through running Structural Equation Modeling (SEM) demonstrated that teachers’ emotional support and trait EI both can associate students’ learning engagement. The final measurement model shows that about 73% of changes in learners’ engagement can be associated by their trait EI and teachers’ emotional support. Conclusions This study underscores the importance of emotional support from teachers and the trait of EI in relation to students’ engagement in learning. Both factors were shown to play a significant role in associating student engagement. Moreover, this study could potentially have wider impacts on members of academic teams.

Deep learning and multimodal remote and proximal sensing are widely used for analyzing plant and crop traits, but many of these deep learning models are supervised and necessitate reference datasets with image annotations. Acquiring these datasets often demands experiments that are both labor-intensive and time-consuming. Furthermore, extracting traits from remote sensing data beyond simple geometric features remains a challenge. To address these challenges, we proposed a radiative transfer modeling framework based on the Helios 3-dimensional (3D) plant modeling software designed for plant remote and proximal sensing image simulation. The framework has the capability to simulate RGB, multi-/hyperspectral, thermal, and depth cameras, and produce associated plant images with fully resolved reference labels such as plant physical traits, leaf chemical concentrations, and leaf physiological traits. Helios offers a simulated environment that enables generation of 3D geometric models of plants and soil with random variation, and specification or simulation of their properties and function. This approach differs from traditional computer graphics rendering by explicitly modeling radiation transfer physics, which provides a critical link to underlying plant biophysical processes. Results indicate that the framework is capable of generating high-quality, labeled synthetic plant images under given lighting scenarios, which can lessen or remove the need for manually collected and annotated data. Two example applications are presented that demonstrate the feasibility of using the model to enable unsupervised learning by training deep learning models exclusively with simulated images and performing prediction tasks using real images.

In recent years, HRB400 and HTRB600 steel bars have become the mainstream standard reinforcing steel used in concrete structures in China. However, significant controversy still exists regarding the selection of material constitutive models and the determination of model parameters for buckling, fatigue, hysteresis, and other material characteristics. In this article, an automated process of multi-parameter calculation of the constitutive model for reinforcing steel – simulation accuracy evaluation of the constitutive model – selection of the constitutive model of reinforcing steel is established based on the hybrid programming method using MATLAB and OpenSees software. First, tensile and low-cycle fatigue tests were carried out on HRB400 and HTRB600 steel bars. Second, based on the constitutive model in OpenSees software and the skeleton curve and characteristics such as yielding, fatigue, and hysteresis, the constitutive model parameters of HRB400 and HTRB600 steel bars are determined using indirect and direct fitting methods. Finally, the five similarity parameters of the simulated normalized cumulative hysteretic energy dissipation coefficient are compared with the test results. The results indicate that the simulation accuracy of the Reinforcing Steel model exceeds 72%, which is higher than other four models, making it the best choice for reinforcing steel in numerical simulation.

Stomatal conductance (gs) is a crucial component of plant physiology, as it links plant productivity and water loss through transpiration. Estimating gs indirectly through leaf temperature (Tl) measurement is common for reducing the high labor cost associated with direct gs measurement. However, the relationship between observed Tl and gs can be notably affected by local environmental conditions, canopy structure, measurement scale, sample size, and gs itself. To better understand and quantify the variation in the relationship between Tl measurements to gs, this study analyzed the sensitivity of Tl to gs using a high-resolution three-dimensional model that resolves interactions between microclimate and canopy structure. The model was used to simulate the sensitivity of Tl to gs across different environmental conditions, aggregation scales (point measurement, infrared thermometer, and thermographic image), and sample sizes. Results showed that leaf-level sensitivity of Tl to gs was highest under conditions of high net radiation flux, high vapor pressure deficit, and low boundary layer conductance. The study findings also highlighted the trade-off between measurement scale and sample size to maximize sensitivity. Smaller scale measurements (e.g., thermocouple) provided maximal sensitivity because they allow for exclusion of shaded leaves and the ground, which have low sensitivity. However, large sample sizes (up to 50 to 75) may be needed to differentiate genotypes. Larger-scale measurements (e.g., thermal camera) reduced sample size requirements but include low-sensitivity elements in the measurement. This work provides a means of estimating leaf-level sensitivity and offers quantitative guidance for balancing scale and sample size issues.

Summary: Poor skin wound healing, which is common in patients with diabetes, is related to imbalanced macrophage polarization. Here, we find that nutrition sensor GCN2 (general control nonderepressible 2) and its downstream are significantly upregulated in human skin wound tissue and mouse skin wound macrophages, but skin wound-related GCN2 expression and activity are significantly downregulated by diabetes and hyperglycemia. Using wound healing models of GCN2-deleted mice, bone marrow chimeric mice, and monocyte-transferred mice, we show that GCN2 deletion in macrophages significantly delays skin wound healing compared with wild-type mice by altering M1 and M2a/M2c polarization. Mechanistically, GCN2 inhibits M1 macrophages via OXPHOS-ROS-NF-κB pathway and promotes tissue-repairing M2a/M2c macrophages through eukaryotic translation initiation factor 2 (eIF2α)-hypoxia-inducible factor 1α (HIF1α)-glycolysis pathway. Importantly, local supplementation of GCN2 activator halofuginone efficiently restores wound healing in diabetic mice with re-balancing M1 and M2a/2c polarization. Thus, the decreased macrophage GCN2 expression and activity contribute to poor wound healing in diabetes and targeting GCN2 improves wound healing in diabetes.

The energy storage plays a prominent part in the life histories of many animals inhabiting cold harsh environment, thus anuran amphibians rely on larger residual energy stores from post-hibernation to cope with unfavourable weather conditions before breeding. As the habitat conditions often change in different locations, selective pressure for energy storage could also vary. However, we still have limited knowledge on whether anurans living under different environmental backgrounds would adopt suitable strategies to cope with energy demands during reproduction. Here, we examined patterns of energy storage in spring (after hibernation and before reproduction) in seven plateau brown frog (Rana kukunoris) populations with different climatic conditions in the eastern Tibetan Plateau. After removing the effects of age and body size, liver weights of both sexes and fat body weights in males were negatively correlated with temperature, suggesting that these reserves were critical for this anuran to survive through harsh and extended dormancy period under uncertain environmental conditions. Additionally, reproductive investment in both sexes could partly explain the increase in post-hibernation energy stores with decreasing temperature. Males had relatively heavier liver and fat body weights than females, indicating that males store more energy reserves for breeding activity compared with females. Therefore, we suggest that both the variation of environmental conditions and sexual differentiation of reproductive roles play a prominent role in shaping the energy allocation and reserve patterns in the dormancy and breeding of amphibian species.

Abstract Background Airborne fine particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5) pollution is associated with the prevalence of respiratory diseases, including asthma, bronchitis and chronic obstructive pulmonary disease. In patients with those diseases, circulating asymmetric dimethylarginine (ADMA) levels are increased, which contributes to airway nitric oxide deficiency, oxidative stress and inflammation. Overexpression of dimethylarginine dimethylaminohydrolase 1 (DDAH1), an enzyme degrading ADMA, exerts protective effects in animal models. However, the impact of DDAH1/ADMA on PM2.5-induced lung injury has not been investigated. Methods Ddah1 −/− and DDAH1-transgenic mice, as well as their respective wild-type (WT) littermates, were exposed to either filtered air or airborne PM2.5 (mean daily concentration ~ 50 µg/m3) for 6 months through a whole-body exposure system. Mice were also acutely exposed to 10 mg/kg PM2.5 and/or exogenous ADMA (2 mg/kg) via intratracheal instillation every other day for 2 weeks. Inflammatory response, oxidative stress and related gene expressions in the lungs were examined. In addition, RAW264.7 cells were exposed to PM2.5 and/or ADMA and the changes in intracellular oxidative stress and inflammatory response were determined. Results Ddah1 −/− mice developed more severe lung injury than WT mice after long-term PM2.5 exposure, which was associated with greater induction of pulmonary oxidative stress and inflammation. In the lungs of PM2.5-exposed mice, Ddah1 deficiency increased protein expression of p-p65, iNOS and Bax, and decreased protein expression of Bcl-2, SOD1 and peroxiredoxin 4. Conversely, DDAH1 overexpression significantly alleviated lung injury, attenuated pulmonary oxidative stress and inflammation, and exerted opposite effects on those proteins in PM2.5-exposed mice. In addition, exogenous ADMA administration could mimic the effect of Ddah1 deficiency on PM2.5-induced lung injury, oxidative stress and inflammation. In PM2.5-exposed macrophages, ADMA aggravated the inflammatory response and oxidative stress in an iNOS-dependent manner. Conclusion Our data revealed that DDAH1 has a marked protective effect on long-term PM2.5 exposure-induced lung injury.

In this digital age, where parental attention is often diverted by digital engagement, the phenomenon of “parental phubbing,” defined as parents ignoring their children in favor of mobile devices, is scrutinized for its potential impact on child development. This study, utilizing questionnaire data from 612 parents and Structural Equation Modeling (SEM) with moderated mediation, examines the potential association between parental phubbing and young children’s electronic media use. The findings revealed a correlation between parental phubbing and increased electronic media use in children. Parent–child conflict, informed by instances of parental phubbing, was identified as a partial mediator in this relation. Notably, children’s emotion regulation emerged as a moderating factor, with adept regulation linked to reduced adverse effects of parental phubbing and improved relational harmony. These findings underscore the importance of parental awareness of their digital behaviors and the benefits of fostering robust parent–child relationships and supporting children’s emotional regulation to nurture well-adjusted “digital citizens” in the contemporary media landscape.

Thymic epithelial cells (TECs) are essential for the production of self-tolerant T cells. Single-cell ATAC-seq of medullary TECs suggests that Sirt6-mediated epigenetic regulation may regulate the development of thymic tuft cells from these TECs.

Abstract Stem cells from human exfoliated deciduous teeth (SHED) can be used as a potential clinical material. But the use of xenogeneic ingredients will increase the risk of zoonotic disease transmission. Human platelet lysate (HPL) is a potential surrogate and used in human cell expansion with reliability in clinical applications. In this study, we synthesized chitosan/gelatin/gellan gum hydrogel supplemented with HPL and investigated the effect of 3D culture for SHED. TMT-tagged proteomics was used to decipher the secretome protein profiles of SHEDs and a total of 3209 proteins were identified, of which 23 were up-regulated and 192 were down-regulated. The results showed that hydrogel supplemented with HPL promoted SHED proliferation. After induction, the hydrogel coating contributed to osteogenic differentiation, adipogenic differentiation and differentiation into neural-like cells of SHED. SHED encapsulated in a hydrogel promotes migration and angiogenesis of HUVEC. In conclusion, our research found that hydrogel supplemented with HPL can be used as a method for SHED in standardized production and can contribute to the clinical application of SHED in cell therapy.

A facile and efficient visible-light-mediated method for directly converting 1,4-naphthoquinones into dihydrocyclo-buta[b]naphthalene-3,8-diones (DHCBNDOs) under mild and clean conditions without using any photocatalysts is reported. This approach exhibited favorable compatibility with functional groups and afforded a series of DHCBNDOs with excellent regioselectivity and high yields. Moreover, detailed mechanism studies were carried out both experimentally and theoretically. The readily accessible, low-cost and ecofriendly nature of the developed strategy will endow it with attractive applications in organic and medicinal chemistry.

Non-alcoholic fatty liver disease (NAFLD) is the most common among lipid metabolism disorders. Autophagy plays an important role in lipid metabolism in NAFLD. Pueraria flavonoids, the main active ingredients of Pueraria lobata, exert antioxidant and anti-inflammatory effects. Herein, we report the potential lipid-lowering and anti-inflammatory effects of Pueraria flavonoids on NAFLD induced by a high-fat diet. In vivo and in vitro experiments showed that Pueraria flavonoids reduced intracellular lipid deposition by inhibiting lipid synthesis and the release of pro-inflammatory cytokines. We analyzed the autophagy flux by mRFP-GFP-LC3 plasmid transfection to assess the role of autophagy in intracellular scavenging. After treating mice fed on high fat and HepG2 cells with Pueraria flavonoids, the number of autophagosomes increased significantly, along with the level of autophagy. The autophagy loss after siRNA transfection aggravated lipid deposition and the release of inflammatory cytokines. Mechanistically, Pueraria flavonoids trigger autophagy through PI3K/Akt/mTOR signaling pathway to reduce lipid deposition and inflammation. In summary, our results showed that Pueraria flavonoids stimulated autophagy by inhibiting the PI3K/Akt/mTOR signaling pathway, thereby reducing intracellular lipid accumulation and inflammation levels and alleviating NAFLD.

In recent years, the incidence of depressive symptoms among Chinese college students has been increasing. Studies have shown that depressive symptoms are related to a variety of psychosocial factors, among which neuroticism, resilience, and attention bias are most notably related, but the correlation among the three is not clear. This study aimed to investigate the influence mechanisms of different degrees of resilience, attentional bias, and neuroticism in the formation of depressive symptoms. The college freshmen of this study were selected through stratified multi-stage cluster sampling. Students provided informed consent and then completed a general situation questionnaire and four scales: the Chinese version of the Connor–Davidson Resilience Scale, the Attention to Positive and Negative Information Scale, the Eysenck Personality Questionnaire, and the Zung Self-Rating Depressive Symptoms Scale. In total, 1,493 freshmen participated in the research group. Our results showed that low resilience, negative attention bias, and high neuroticism jointly increased the risk of depressive symptoms. There is a significant correlation between these three factors and depressive symptoms. Additionally, strength, tenacity, and attention bias all had more significant effects on the occurrence of depressive symptoms. These findings indicate that there may be an important psychological mechanism for the occurrence, development, and poor prognosis of depressive symptoms.

Summary: The generation of mature T cells and establishment of central tolerance is predominantly orchestrated by thymic epithelial cells (TECs). Proprotein convertases are responsible for the proteolysis of proproteins into their mature bioactive counterparts. Here, we found that Furin, a member of the subtilisin/kexin-like PCs family, is highly expressed in TECs compared with other members of this family. TEC-specific deletion of Furin caused severe thymic atrophy and predominantly reduced the number of medullary TECs and thymic tuft cells, and to a less degree, cortical TECs. Furin deletion attenuated the proliferation of TECs, impaired thymopoiesis, and led to autoimmune disorders in mice. Furin promotes the development of TECs via cleavage of proIGF1 receptor and pro-Insulin receptor and the activation of downstream ERK/MAPK and Akt signaling pathways. Thus, this study uncovered the role of furin in TEC development and function and highlighted the importance of post-translational modification of immature proproteins in TEC biology.

To improve the performance of conventional double-effect absorption refrigeration systems (DEARS), new series parallel (SP) and reverse parallel (RP) configurations using LiCl-H2O and LiBr-H2O as working fluids, combined with two vapor compressors (VC), are proposed and thermodynamically evaluated. The effects of the distribution ratio (D) and compression ratio (CR) on the system performance are discussed. The results reveal that both configurations can extend the operation ranges of DEARS effectively at a higher distribution ratio, and the performance for low-grade heat source utilization is improved substantially by the use of VC. The compressor positioned between the evaporator and absorber is superior to that between the high-pressure generator and low-pressure generator because of the better performance improvement and larger operating ranges. In all the examined cases, LiCl-H2O systems perform better than LiBr-H2O systems in terms of the coefficient of performance (COP) and exergetic efficiency. At the higher CR of approximately 2, the compression-assisted DEARS can be driven by heat sources below 100 °C with high levels of COPs above 1.16 for the LiBr-H2O working pair and 1.29 for the LiCl-H2O working pair. The system can operate at the optimum condition by adjusting the CR values according to the characteristics of the heat sources.

Abstract Stem cell therapy has shown great efficacy in many diseases. However, the treatment mechanism is still unclear, which is a big obstacle for promoting clinical research. Therefore, it is particularly important to track transplanted stem cells in vivo, find out the distribution and condition of the stem cells, and furthermore reveal the treatment mechanism. Many tracking methods have been developed, including magnetic resonance imaging (MRI), fluorescence imaging, and ultrasound imaging (UI). Among them, MRI and UI techniques have been used in clinical. In stem cell tracking, a major drawback of these technologies is that the imaging signal is not strong enough, mainly due to the low cell penetration efficiency of imaging particles. Cell penetrating peptides (CPPs) have been widely used for cargo delivery due to its high efficacy, good safety properties, and wide delivery of various cargoes. However, there are few reports on the application of CPPs in current stem cell tracking methods. In this review, we systematically introduced the mechanism of CPPs into cell membranes and their advantages in stem cell tracking, discussed the clinical applications and limitations of CPPs, and finally we summarized several commonly used CPPs and their specific applications in stem cell tracking. Although it is not an innovation of tracer materials, CPPs as a powerful tool have broad prospects in stem cell tracking. Graphic abstract

The pathology of Alzheimer's disease (AD) is complex and heterogeneous, and there are currently no drugs that can stop its progression. The failure of traditional chemical small-molecule drug development showed the weakness of single target and made researchers look to cell therapy with multiple regulatory effects. Stem cells from human exfoliated deciduous teeth (SHED) are a kind of neural crest-derived mesenchymal stem cells which have broad prospects in the treatment of neurodegenerative diseases. In this study, we demonstrated the therapeutic effects of SHED in AD mice, including behavioral improvement, neuronal protection, and alleviation of neuroinflammation. Tracking experiments on SHED showed that some of the transplanted cells could enter the brain. To elucidate the role played by the majority of cells transplanted into veins, blood proteomic assays were performed. Data are available via ProteomeXchange with identifier PXD030313. Among the altered proteins, the PPAR pathway related to energy metabolism was considered to be an important signaling pathway involved in regulation through gene ontology analysis and pathway analysis. Western blot showed that the transplantation of SHED improved the glucose metabolism in AD mice by increasing the PPARγ signaling pathway. These results suggested that SHED have a potential in relieving AD pathological symptoms and improving behavioral cognition. The therapeutic mechanism of SHED is related to up-regulating PPARγ signaling pathway and reducing neuronal damage.

Abstract Parkinson’s disease (PD), the second most common neurodegenerative disease worldwide, is caused by the loss of dopaminergic (DAergic) neurons in the substantia nigra resulting in a series of motor or non-motor disorders. Current treatment methods are unable to stop the progression of PD and may bring certain side effects. Cell replacement therapy has brought new hope for the treatment of PD. Recently, human dental tissue-derived mesenchymal stem cells have received extensive attention. Currently, dental pulp stem cells (DPSCs) and stem cells from human exfoliated deciduous teeth (SHED) are considered to have strong potential for the treatment of these neurodegenerative diseases. These cells are considered to be ideal cell sources for the treatment of PD on account of their unique characteristics, such as neural crest origin, immune rejection, and lack of ethical issues. In this review, we briefly describe the research investigating cell therapy for PD and discuss the application and progress of DPSCs and SHED in the treatment of PD. This review offers significant and comprehensive guidance for further clinical research on PD.

Environmental stress is generally regarded as an important evolutionary force for promoting the differentiation of shape, structure and function of animal organs closely related to survival and reproduction. Geographical variation of temperature and corresponding change in intensity of male-male competition might drive inter-population differences in directional testes asymmetry (DTA). Here, we investigated inter-population variation in DTA of the brown frog (Rana kukunoris) at seven different altitudes on the eastern Tibetan Plateau. We found that the size of right testes increased with temperature, but not left testes. We also found that male age, body mass or body condition, and testis mass had not effect on DTA, suggesting that heavier or older R. kukunoris males or those with larger testes had not stronger DTA. The operational sex ratio did not affect DTA, but there was a positive correlation between DTA and temperature, suggesting that differences in the length of activity period and resources availability across locations may affect the energy budget of this frog, resulting in a gradual change in reproduction energy parallel to increasing temperature.

An increasing number of epidemiological studies have shown that there is a significant inverse relationship between the onset of Alzheimer's disease/Parkinson's disease (AD/PD) and cancer, but the mechanism is still unclear. Considering that intestinal flora can connect them, we tried to explain this phenomenon from the intestinal flora. This review briefly introduced the relationship among AD/PD, cancer, and intestinal flora, studied metabolites or components of the intestinal flora and the role of intestinal barriers and intestinal hormones in AD/PD and cancer. After screening, a part of the flora capable of participating in the occurrence processes of the three diseases at the same time was obtained, the abundance changes of the special flora in AD/PD and various types of cancers were summarized, and they were classified according to the flora function and abundance, which in turn innovatively and reasonably explained the fact that AD/PD and cancer showed certain antagonism in epidemiological statistics from the perspective of intestinal flora. This review also proposed that viewing the risk relationship between diseases from the perspective of intestinal flora may provide new research ideas for the treatment of fecal microbiota transplantation (FMT) and related diseases.

In order to study the application of computer digital image processing technology in film and television (FAT) animation visual sensing expression, by studying the principle of digital image processing technology and visual sensing technology, a spatial image adaptive steganography image enhancement algorithm by multiscale filters is proposed to carry out enhancement processing of the original image in FAT production. This algorithm can provide more high-quality and refined original materials for FAT animation production, which is convenient for FAT animation postproduction to produce higher-resolution and clear FAT works. Finally, the algorithm is verified. The results show that the spatial image adaptive steganography image enhancement algorithm has high security, and the highest average detection error rate is 25.06%. When α=0.4, the security of the spatial image adaptive steganography image enhancement algorithm is up to 34.62% and the image distortion rate is low. The established image enhancement algorithm can significantly improve the security of the existing spatial image steganography algorithm under different embedding rates, especially at a high embedding rate; the improvement of the spatial domain steganography algorithm is greater. The proposed steganographic image enhancement algorithm by image preprocessing has higher security and better image enhancement effect.

The serine/threonine-protein kinase general control nonderepressible 2 (GCN2) is a well-known stress sensor that responds to amino acid starvation and other stresses, making it critical to the maintenance of cellular and organismal homeostasis. More than 20 years of research has revealed the molecular structure/complex, inducers/regulators, intracellular signaling pathways and bio-functions of GCN2 in various biological processes, across an organism’s lifespan, and in many diseases. Accumulated studies have demonstrated that the GCN2 kinase is also closely involved in the immune system and in various immune-related diseases, such as GCN2 acts as an important regulatory molecule to control macrophage functional polarization and CD4+ T cell subset differentiation. Herein, we comprehensively summarize the biological functions of GCN2 and discuss its roles in the immune system, including innate and adaptive immune cells. We also discuss the antagonism of GCN2 and mTOR pathways in immune cells. A better understanding of GCN2′s functions and signaling pathways in the immune system under physiological, stressful, and pathological situations will be beneficial to the development of potential therapies for many immune-relevant diseases.

Plastic film mulching often increases the yield of winter wheat in the Loess Plateau of China, but the physiological mechanisms are unclear, especially in response to the interaction between mulch and water supply. In this study, we investigated the interactive effects of initial soil water (dry, moderate, and wet), soil cover (plastic mulch, bare soil), and seasonal conditions on the dynamics of dry matter partitioning, water-soluble carbohydrates (WSC), and flag leaf senescence, and their relations with yield and its components. Plastic mulch increased dry matter accumulation at anthesis and maturity relative to bare soil, with no interaction with season or initial soil water. Allocation of dry matter to leaf, stem, and spike did not change with soil cover. Compared with bare soil, mulch increased WSC accumulation by 14% at anthesis and its translocation by 16%. Soil cover did not influence the senescence of flag leaf after anthesis as indicated by similar dynamics of the C:N ratio. Grain yield was higher under plastic mulch than bare soil in two out of three seasons, and was associated with a higher translocation amount of WSC and post-anthesis dry matter that linked grain weight, grain number, and harvest index.

Stem cells in different types may interact with each other to maintain homeostasis or growth and the interactions are complicated and extensive. There is increasing evidence that mesenchymal-epithelial interactions in early morphogenesis stages of both tooth and hair follicles show many similarities. In order to explore whether stem cells from one tissue could interact with cells from another tissue, a series of experiments were carried out. Here we successfully extracted and identified stem cells from human exfoliated deciduous teeth (SHED) of 8–12 years old kids, and then found that SHED could promote hair regeneration in a mouse model. In vitro, SHED shortened the hair regeneration cycle and promoted the proliferation and aggregation of dermal cells. In vivo, when SHED and skin cells of C57 mice were subcutaneously co-transplanted to nude mice, more hair was formed than skin cells without SHED. To further explore the molecular mechanism, epidermal and dermal cells were freshly extracted and co-cultured with SHED. Then several signaling molecules in hair follicle regeneration were detected and we found that the expression of Sonic Hedgehog (Shh) and Glioma-associated oncogene 1 (Gli1) was up-regulated. It seems that SHED may boost the prosperity of hairs by increase Shh/Gli1 pathway, which brings new perspectives in tissue engineering and damaged tissue repairing.

The breeding biology of the little egret (Egretta garzetta) was studied in 20 nests within the mixed-species breeding colonies at Nanchong, Sichuan, Southwest China, in 2006. By measuring a set of physical characteristics of vegetation at the nests and at a set of 20 randomly chosen sites we showed that birds preferentially used taller trees in areas with fewer shrubs of higher species diversity. Nests at lower locations in trees had marginally lower hatching success due to their destruction by humans; this destruction contributed marginally significantly to lowering of the total nesting success in all studied nests. Although gale winds also had a negative effect on breeding success, the anthropogenic influences were a greater factor in reproductive failure. We found similar effects in our review of literature on breeding success of the little egret from various geographical areas. Our results may be of use by conservation organizations in their actions to protect colonies of the little egret.

When a commercial vehicle diesel engine works for an extended period of time at the torque spot, it can easily cause a mechanical failure due to the high temperature of the piston. In this paper, the temperature plug method was used to measure the temperature of the piston at the maximum torque spot. In order to reduce the failure caused by high temperature, the finite element analysis software Ansys was used in this paper to study the effects of different thicknesses of ceramic coatings on the piston surface of a diesel engine on the maximum temperature of the piston substrate. The bonding layer of the ceramic coating was NiCoCrAlY with a thickness of 0.1 mm, and the insulating layer was a La2Zr2O7 coating with respective thicknesses of 0.2 mm, 0.3 mm, 0.5 mm, 0.7 mm, and 0.9 mm. When the thickness of the ceramic coating was increased from 0.3 mm to 1.0 mm, the maximum temperature of the piston base decreased from 347.9 °C to 267.46 °C. This showed that the use of a thermal-barrier coating can effectively reduce the maximum temperature of the piston and greatly improve the safety of engine operation.

Although some advances have been made in understanding the molecular regulation of mTEC development, the role of epigenetic regulators in the development and maturation of mTEC is poorly understood. Here, using the TEC-specific Sirt6 knockout mice, we found the deacetylase Sirtuin 6 (Sirt6) is essential for the development of functionally competent mTECs. First of all, TEC-specific Sirt6 deletion dramatically reduces the mTEC compartment, which is caused by reduced DNA replication and subsequent impaired proliferation ability of Sirt6-deficient mTECs. Secondly, Sirt6 deficiency specifically accelerates the differentiation of mTECs from CD80–Aire– immature population to CD80+Aire– intermediate mature population by promoting the expression of Spib. Finally, Sirt6 ablation in TECs markedly interferes the proper expression of tissue-restricted antigens (TRAs) and impairs the development of thymocytes and nTreg cells. In addition, TEC conditional knockout of Sirt6 results in severe autoimmune disease manifested by reduced body weight, the infiltration of lymphocytes and the presence of autoantibodies. Collectively, this study reveals that the expression of epigenetic regulator Sirt6 in TECs is crucial for the development and differentiation of mTECs, which highlights the importance of Sirt6 in the establishment of central immune tolerance.

Since mesenchymal stem cells derived from human teeth are characterized as having the properties of excellent proliferation, multilineage differentiation, and immune regulation. Dental stem cells exhibit fibroblast-like microscopic appearance and express mesenchymal markers, embryonic markers, and vascular markers but do not express hematopoietic markers. Dental stem cells are a mixed population with different sensitive markers, characteristics, and therapeutic effects. Single or combined surface markers are not only helpful for understanding the subpopulation of mixed stem cell populations according to cell function but also for improving the stable treatment effect of dental stem cells. Focusing on the discovery and characterization of stem cells isolated from human teeth over the past 20 years, this review outlines the effect of marker sorting on cell proliferation and differentiation ability and the assessment of the clinical application potential. Classified dental stem cells from markers and functional molecules can solve the problem of heterogeneity and ensure the efficacy of cell therapy strategies including dentistry, neurologic diseases, bone repair, and tissue engineering.

Human gingival mesenchymal stem cells (GMSCs) are derived from migratory neural crest stem cells and have the potential to differentiate into neurons. Metformin can inhibit stem–cell aging and promotes the regeneration and development of neurons. In this study, we investigated the potential of metformin as an enhancer on neuronal differentiation of GMSCs in the growth environment of chitosan hydrogel. The crosslinked chitosan/β–glycerophosphate hydrogel can form a perforated microporous structure that is suitable for cell growth and channels to transport water and macromolecules. GMSCs have powerful osteogenic, adipogenic and chondrogenic abilities in the induction medium supplemented with metformin. After induction in an induction medium supplemented with metformin, Western blot and immunofluorescence results showed that GMSCs differentiated into neuron–like cells with a significantly enhanced expression of neuro–related markers, including Nestin (NES) and β–Tubulin (TUJ1). Proteomics was used to construct protein profiles in neural differentiation, and the results showed that chitosan hydrogels containing metformin promoted the upregulation of neural regeneration–related proteins, including ATP5F1, ATP5J, NADH dehydrogenase (ubiquinone) Fe–S protein 3 (NDUFS3), and Glutamate Dehydrogenase 1 (GLUD1). Our results help to promote the clinical application of stem–cell neural regeneration.

Many environmental factors such as temperature or food level may influence growth and mortality risks of ectothermic vertebrates in both aquatic and terrestrial habitats. In this study, plasticity in growth rates, survival, larval period, and size at metamorphosis were examined in Bufo gargarizans gargarizans larvae under different combinations of temperature and food level. Our results showed that larvae metamorphosed at an older age when reared at 17.3°C. A significant interaction between food level and temperature revealed that the food level has obviously affected length of larval period when tadpoles raised at 17.3 °C, but not at 27.3 or 31.3 °C. Also, we found clear evidence that growth rates are influenced by both temperature and food level. Interestingly, tadpoles reared at 17.3 °C had larger size at metamorphosis than those reared at other temperatures, suggesting that B. g. gargarizans larvae reared at cold temperatures have a longer developmental period but they are also larger as metamorphs than conspecifics reared at warmer temperatures. Therefore, the global climate change or local manipulations of the environment may promote growth and development of B. g. gargarizans larvae, but not large size at metamorphosis.

Fine particulate matter (PM2.5) airborne pollution increases the risk of respiratory and cardiovascular diseases. Although metformin is a well-known antidiabetic drug, it also confers protection against a series of diseases through the activation of AMP-activated protein kinase (AMPK). However, whether metformin affects PM2.5-induced adverse health effects has not been investigated. In this study, we exposed wild-type (WT) and AMPKα2−/− mice to PM2.5 every other day via intratracheal instillation for 4 weeks. After PM2.5 exposure, the AMPKα2−/− mice developed more severe lung injury and cardiac dysfunction than were developed in the WT mice; however the administration of metformin was effective in attenuating PM2.5-induced lung injury and cardiac dysfunction in both the WT and AMPKα2−/− mice. In the PM2.5-exposed mice, metformin treatment resulted in reduced systemic and pulmonary inflammation, preserved left ventricular ejection fraction, suppressed induction of pulmonary and myocardial fibrosis and oxidative stress, and increased levels of mitochondrial antioxidant enzymes. Moreover, pretreatment with metformin significantly attenuated PM2.5-induced cell death and oxidative stress in control and AMPKα2-depleted BEAS-2B and H9C2 cells, and was associated with preserved expression of mitochondrial antioxidant enzymes. These data support the notion that metformin protects against PM2.5-induced adverse health effects through a pathway that appears independent of AMPKα2. Our findings suggest that metformin may also be a novel drug for therapies that treat air pollution associated disease. Keywords: Metformin, AMPKα2, PM2.5, Lung injury, Cardiac dysfunction

The clinical use of doxorubicin for cancer therapy is limited by its cardiotoxicity, which involves cardiomyocyte apoptosis and oxidative stress. Previously, we showed that general control nonderepressible 2 (GCN2), an eukaryotic initiation factor 2α (eIF2α) kinase, impairs the ventricular adaptation to chronic pressure overload by affecting cardiomyocyte apoptosis. However, the impact of GCN2 on Dox-induced cardiotoxicity has not been investigated. In the present study, we treated wild type (WT) and Gcn2−/− mice with four intraperitoneal injections (5 mg/kg/week) to induce cardiomyopathy. After Dox treatment, Gcn2−/− mice developed less contractile dysfunction, myocardial fibrosis, apoptosis, and oxidative stress compared with WT mice. In the hearts of the Dox-treated mice, GCN2 deficiency attenuated eIF2α phosphorylation and induction of its downstream targets, activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP), and preserved the expression of anti-apoptotic factor Bcl-2 and mitochondrial uncoupling protein-2(UCP2). Furthermore, we found that GCN2 knockdown attenuated, whereas GCN2 overexpression exacerbated, Dox-induced cell death, oxidative stress and reduction of Bcl-2 and UCP2 expression through the eIF2α-CHOP-dependent pathway in H9C2 cells. Collectively, our data provide solid evidence that GCN2 has a marked effect on Dox induced myocardial apoptosis and oxidative stress. Our findings suggest that strategies to inhibit GCN2 activity in cardiomyocyte may provide a novel approach to attenuate Dox-related cardiotoxicity. Keywords: GCN2, Doxorubicin, Cardiotoxicity, Oxidative stress, CHOP, UCP2

Blastocystis is one of the most common intestinal parasites in humans worldwide. To understand its prevalence and to explore the risk factors for Blastocystis in humans in developing countries, a molecular epidemiological investigation of Blastocystis was conducted in ethnic minority groups on both sides of the China–Myanmar border. A total of 461 fecal specimens were collected from 289 Yao people in China and 172 Wa people in Myanmar, together with a questionnaire for each participant. Based on sequence analysis of the partial small subunit of ribosomal RNA (SSU rRNA) gene (barcode region or 260 bp region), an average prevalence of 6.29% (29/461) was observed, with 4.50% (13/289) in Yao people and 9.30% (16/172) in Wa people. Twenty-two Blastocystis isolates were successfully subtyped by sequence analysis of the barcode region. Three subtypes were identified: ST1 (n = 7), ST3 (n = 13) and ST4 (n = 2). A statistical difference in the prevalence of Blastocystis was only observed between children (12.37%, 12/97) and adults (4.95%, 16/323), and between not washing hands (11.02%, 14/127) and washing hands (4.76%, 15/315) after using toilets, emphasizing the importance and necessity of health education in people in the investigated areas, especially in children.

This study documents the occurrence of sulfonamides (SA) and their acetylated metabolite compounds in an aquaculture environment in China. Five parent compounds of SAs and four metabolites were detected in fish water, surface water, and groundwater. The most relevant compounds in terms of frequency of detection and maximum concentrations detected were sulfamethoxazole and sulfachinoxalin in fish water and surface water, with average concentrations of 541 ng/L and 274 ng/L, respectively. The acetylated metabolites were detected at higher concentrations than their parent compounds in groundwater, although they were much lower than in the surface environment. The recent appearance of acetylated metabolites of SAs in groundwater samples demonstrates the environmental health concern and the need of further study.

Testes asymmetry theory predicts that males in good condition or mature age may be able to develop larger degrees of directional asymmetry than males in poor condition or younger age. In this study, we tested the testes asymmetry theory in the Bufo gargarizans. We found that B. gargarizans has a significant directional asymmetry in testes mass, with left testis being significantly larger than right testis. Male body condition was correlated with relative testes mass and absolute testes asymmetry, but not correlated with relative testes asymmetry. Therefore, we suggested that males in good body condition have the higher ability of sperm competition than males in poor body condition. Additionally, male age was correlated with absolute testes asymmetry, but not correlated with relative testes mass and testes asymmetry, thus not supporting the hypothesis that males with a higher degree of directional asymmetry survive better.