Development and genetic regulation of pollen intine in Arabidopsis and rice.

Pollen intine serves as a protective layer situated between the pollen exine and the plasma membrane. It performs essential functions during pollen development, including maintaining the morphological structure of the pollen, preventing the loss of pollen contents, and facilitating pollen germination. The formation of the intine layer commences at the bicellular pollen stage. Pectin, cellulose, hemicellulose and structural proteins are the key constituents of the pollen intine. In Arabidopsis and rice, numerous regulatory factors associated with polysaccharide metabolism and material transport have been identified, which regulate intine development. In this review, we elucidate the developmental processes of the pollen wall and provide a concise summary of the research advancements in the development and genetic regulation of the pollen intine in Arabidopsis and rice. A comprehensive understanding of intine development and regulation is crucial for unraveling the genetic network underlying intine development in higher plants.

Effects of porous structure on the deformation failure mechanism of cement sheaths for wellbores.

The influence and mechanism of porous structure on the deformation failure of cement sheaths under hydraulic pressure is still unclear. To solve this problem, a net slurry cement sheath and a liquid silicon cement sheath were prepared by using a cement material and a liquid silicon suspension. The distributions of the pore radius and spatial location were analyzed using computed tomography scanning and statistics to obtain their probability density distribution functions. Based on the distribution functions, the single-layer and double-layer porous reconstruction models of the net slurry cement sheath and liquid silicon cement sheath were constructed using a FLAC 3D program. A series of numerical simulations were conducted to study the deformation failure of the cement sheaths under in situ stress and hydraulic pressure. The effects of the porous and double-layer structures on the breakdown pressure, plastic failure zone, radial deformation, and stress distribution of the cement sheaths were analyzed. As a result, the mechanisms for the influence of the porous and double-layer structures on the failure mode, failure path, and interaction between the cement sheath and metal casing were revealed. The results of this research provide a theoretical basis for an in-depth understanding of the failure mechanisms of porous cement sheaths.

Effect of prior drought and heat stress on Camellia sinensis transcriptome changes to Ectropis oblique (Lepidoptera: Geometridae) resistance.

Tea plants are continuously confronted with a wide range of biotic and abiotic stressors in the field, which can occur concurrently or sequentially. To elucidate the molecular mechanisms in responses to such individual and combined stresses, we used RNAseq to compare the temporal changes in the transcriptome of Camellia sinensis to Ectropis oblique Prout alone or in combination with exposure to drought and heat. Compared with the individual stress, tea plants exhibit significant differences in transcriptome profiles under the combined stresses. Additionally, many unique genes exhibited significant differences in expression in individual and combined stress conditions. Our research showed novel insights into the molecular mechanisms of E. oblique Prout resistance in tea plants and provided a valuable resource for developing tea varieties with broad spectrum stress tolerance.

VO2-enabled transmission-reflection switchable coding terahertz metamaterials.

Coding metamaterials have offered unprecedented degrees of freedom to manipulate electromagnetic waves in time and frequency domains in terms of various coding sequences, however, it is still challenging to realize dynamic coding metamaterials in the terahertz range. Here, we propose VO2-enabled transmission-reflection switchable coding terahertz metamaterials consisting of multilayered gold and VO2 patterns. The insulator-to-metal transition of VO2 leads to switch between the refractive and reflective scattering beams by changing the temperature. The four 2-bit elements are used to construct coding metasurface-based OAM generator with l = 1. Remarkably, the transmission-reflection switching functionality of the coding metasurface can be achieved at different frequencies. In addition, the novel designs in our work can achieve EM waves manipulation and provide a useful method to dynamically switch transmission-reflection response in the THz frequency regime.

Preparation, characterization and immune activity of Codonopsis pilosula polysaccharide loaded in chitosan-graphene oxide.

The purpose of this study was to investigate the effects of chitosan graphene oxide Codonopsis pilosula polysaccharide (CS-GO-CPP) complex on the immune function of macrophage cells (RAW264.7). In this experiment, chitosan (CS) was combined with graphene oxide (GO) by electrostatic action to prepare CS-GO nanocomposites, and it was used as a carrier to load Codonopsis pilosula polysaccharide (CPP) onto CS-GO to prepare CS-GO-CPP. Using infrared spectroscopy detection, zeta potential detection, and thermogravimetric analysis, we conduct a preliminary analysis of the structure of CS-GO-CPP. Macrophages were employed to evaluate CS-GO-CPP immunomodulatory activity and the possible mechanism responsible for the activation of macrophages in vitro. The results showed that compared with CPP, CS-GO-CPP did not change the basic structure of polysaccharide, and its thermal stability was improved. 0.78- 12.5 µg·mL-1 of CS-GO-CPP could significantly promote the phagocytic activity of RAW264.7 cells (P < 0.05) and significantly increase NO content, IL-4 and IFN-γ secretion, the expression of CD40, CD86, and F4/80 (P < 0.05). CS-GO-CPP might activate the NF-κB signaling pathway and induce the nuclear translocation of NF-κB p65. In conclusion, CS-GO-CPP has a capacity to activate RAW264.7 cells for an improvement of immunomodulation activities, which might be through NF-κB signaling pathway.

Aberrant HO-1/NQO1-Reactive Oxygen Species-ERK Signaling Pathway Contributes to Aggravation of TPA-Induced Irritant Contact Dermatitis in Nrf2-Deficient Mice.

NF-erythroid 2-related factor 2 (Nrf2) is a major transcription factor to protect cells against reactive oxygen species (ROS) and reactive toxicants. Meanwhile, Nrf2 can inhibit contact dermatitis through redox-dependent and -independent pathways. However, the underlying mechanisms of how Nrf2 mediates irritant contact dermatitis (ICD) are still unclear. In this article, we elucidated the role of Nrf2 in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced acute ICD. Our study demonstrated that the ear thickness, redness, swelling, and neutrophil infiltration were significantly increased, accompanied by increased expression of inflammatory cytokines (IL-1α, IL-1ß, IL-6, etc.) and decreased expression of antioxidant genes (HO-1 and NQO1) in Nrf2 knockout mice. Moreover, ERK phosphorylation was elevated in mouse embryonic fibroblasts (MEFs) from Nrf2 knockout mouse. Inhibition of ERK significantly alleviated TPA-induced cutaneous inflammation and ROS accumulation in MEFs derived from mouse. Conversely, ROS scavenging inhibited the ERK activation and TPA-induced inflammation in MEFs. Taken together, the findings illustrate the key role of the Nrf2/ROS/ERK signaling pathway in TPA-induced acute ICD.

Spiky titanium dioxide nanoparticles-loaded Plantaginis Semen polysaccharide as an adjuvant to enhance immune responses.

The purpose of this study was to prepare spiky titanium dioxide nanoparticles-loaded Plantaginis Semen polysaccharide (SN-TiO2-PSP), and the structural characterization and immune response of infectious laryngotracheitis (ILT) vaccine in Hetian chickens were investigated. The structural characterization of SN-TiO2-PSP was analyzed by FT-IR, TEM, and TGA analysis. And the immune organs indexes, lymphocytes proliferation, specific antibody levels, and ratios of CD4+ and CD8+ T lymphocytes were studied. Structural characterization results showed that SN-TiO2-PSP has a typical polysaccharide absorption peak and good stability. The SN-TiO2-PSP's shape was similar to sea urchin, and its zeta potential and particle size were 27.56 mV and 976.11 nm, respectively. In vivo results showed that SN-TiO2-PSP could enhance the proliferation of peripheral lymphocytes, specific antibody levels, CD4+ and CD8+ T lymphocytes ratios, IL-4 and INF-γ levels in Hetian chickens vaccinated with ILT vaccine on D7, D14, D21, and D28. In addition, SN-TiO2-PSP not only enhanced the indexes of immune organs but also promoted the development of immune organs. Therefore, SN-TiO2-PSP has immune adjuvant activity and may become a new potential immune adjuvant.

Effectiveness of simulation debriefing methods in nursing education: A systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis aimed to evaluate debriefing methods' effectiveness on learning outcomes for nursing students. DESIGN: A systematic review and meta-analysis were applied according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement. DATA SOURCES: Publications were searched in PubMed, EMBASE, The Cochrane Library, Web of Science, China National Knowledge Infrastructure, and WANFANG (China) databases from inception to 2020. REVIEW METHODS: Two researchers independently retrieved articles and evaluated their quality. Review Manager version 5.3 software was used to conduct the meta-analysis, following the PRISMA guidelines. Bias risk was assessed using the Joanna Briggs Institute manual. Heterogeneity was assessed by I2 statistics. Standardized mean difference (SMD) and 95% confidence intervals (CIs) were used for effect size analysis based on learning outcomes. RESULTS: Sixteen studies were selected in the systematic review and 13 studies with 1637 nursing students were included in the meta-analysis. Five debriefing methods were used in the intervention group. The analysis showed that Debriefing for Meaningful Learning was more effective on the debriefing quality (SMD = 0.52, 95%CI [0.32, 0.72]), and that video-assisted debriefing was more effective on nursing students' experiences (SMD = 0.30, 95%CI [0.02, 0.58]) and critical thinking (SMD = 0.90, 95%CI [0.65, 1.15]) compared with the usual debriefing. However, written debriefing did not show better effects on students' experiences (SMD = -0.22, 95%CI [-0.51, 0.07]), and peer-led debriefing did not show better effects on the debriefing quality compared with the usual debriefing (SMD = -0.15, 95%CI [-1.43, -0.67]). CONCLUSIONS: The study indicated that Debriefing for Meaningful Learning and video-assisted debriefing showed a positive impact on nursing education. Future studies that have larger sample sizes, high-quality debriefing methods, robust study designs, and other learning outcomes are required.

Immunomodulatory effects of polysaccharides enzymatic hydrolysis from Hericium erinaceus on the MODE-K/DCs co-culture model.

The aim of this study was to explore the indirect immunomodulatory activities and its mechanism of enzymatic hydrolysis of Hericium erinaceus polysaccharides (EHEP) in the MODE-K/DCs co-culture model. According to the TEER value, transmission of phenol red and AKP activity of MODE-K cells, single model was established in order to evaluate the eligibility of MODE-K cells monolayer. Then the MODE-K/DCs co-culture model was set up and HEP and EHEP were added into the apical chamber, DCs were obtained for the expression of key surface markers, the ability of phagocytosis, the morphology, the secretion of cytokines and the production of target proteins. We found that after 21 d of culture, the MODE-K cells monolayer became intact and dense, which can be used for the MODE-K/DCs co-culture model. Under the treatment of HEP and EHEP, immature DCs become into mature DCs with the high expression of CD86 and MHCII, the low antigens up-taking, the typical morphology, the more content of IL-12 and TNF-α and the high level of TLR4, MyD88 and NF-κB proteins. However, compared with HEP, EHEP showed the better immunomodulatory activities. These findings indicated that EHEP could indirectly affect the immune function of DCs in the MODE-K/DCs co-culture model.

Large asymmetric anomalous reflection in bilayer gradient metasurfaces.

Gradient metasurfaces have attracted much attention due to intriguing wavefront and polarization manipulation. Here, a bilayer gradient metasurface is constructed by use of a rectangular nanorod layer and its complementary nanoaperture. It reveals asymmetric anomalous reflection and symmetric anomalous transmission for two counter-propagating directions. The dependence of the anomalous reflection and transmission phenomena on nanostructure thickness are numerically studied in optical frequencies. The increasing metallic layer thickness of the gradient metasurface greatly enhances anomalous reflection of the left-handed circularly polarized wave (LCP) for the nanorod side and suppresses anomalous reflection for the other side. Both resonant frequencies of anomalous reflection and transmission linearly shift with the refractive index. The bilayer gradient metasurface is important for realizing wavefront modulation and optical sensing.

Topical Applications of a Novel Emollient Inhibit Inflammation in Murine Models of Acute Contact Dermatitis.

The benefits of emollients for eczematous dermatitis and psoriasis have been thought to be due to the improvements in epidermal function, including epidermal permeability barrier, stratum corneum hydration, and stratum corneum pH. We determined here whether emollient can direct inhibit cutaneous inflammation. Ear inflammation was induced by topical application of either 12-O-tetradecanoylphorbol-13-acetate (TPA) or 1-fluoro-2,4-dinitrofluorobenzene (DNFB). Either 1% hydrocortisone cream or the novel emollient was applied to the right ear of the mice 45 min and 2 hours after TPA or DNFB application. The untreated left ear served as untreated controls. Both ear weight and ear thickness were measured 24 hours after TPA and DNFB application. Topical applications of either hydrocortisone cream or emollient significantly decreased both ear thickness and ear weight in comparison to untreated controls. In DNFB model, hydrocortisone significantly lowered expression levels of mRNA for IL-1α, IL-1ß, and TNFα, while the emollient markedly decreased expression levels of IL-1α and TNFα mRNA. In TPA model, both hydrocortisone and emollient significantly decreased expression levels of IL-1α, IL-1ß, IL-6, and TNFα mRNA. In parallel, inflammatory infiltration was also reduced by topical applications of either hydrocortisone or emollient. These results demonstrate that this novel emollient can directly inhibit cutaneous inflammation in murine models of both acute irritant contact dermatitis and acute allergic contact dermatitis. However, whether this emollient could also alleviate eczematous dermatitis in humans remains to be explored.

Multi-walled carbon nanotube polysaccharide modified Hericium erinaceus polysaccharide as an adjuvant to extend immune responses.

In recent years, the utilization of CS-MWCNT as targeted drug carriers has attracted considerable attention. Hericium erinaceus polysaccharide (HEP) has been reported as an immunostimulant to improve immune responses. This study was focussed on developing CS-MWCNT encapsulating HEP (CS-MWCNT-HEP). Using in mice peritoneal macrophages, we found the immune response could be effectively regulated by CS-MWCNT-HEP, promoted the expression of the MHCII, CD86, F4/80 and gp38. Moreover, the mice immunized with CS-MWCNT-HEP nanoparticles significantly extended PCV2-specific IgG immune response and the levels of cytokines. The results demonstrated that CS-MWCNT-HEP may be a promising drug delivery system for immuno-enhancement.

Machine Learning in Preoperative Prediction of Postoperative Immediate Remission of Histology-Positive Cushing's Disease.

Background: There are no established accurate models that use machine learning (ML) methods to preoperatively predict immediate remission after transsphenoidal surgery (TSS) in patients diagnosed with histology-positive Cushing's disease (CD). Purpose: Our current study aims to devise and assess an ML-based model to preoperatively predict immediate remission after TSS in patients with CD. Methods: A total of 1,045 participants with CD who received TSS at Peking Union Medical College Hospital in a 20-year period (between February 2000 and September 2019) were enrolled in the present study. In total nine ML classifiers were applied to construct models for the preoperative prediction of immediate remission with preoperative factors. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the performance of the models. The performance of each ML-based model was evaluated in terms of AUC. Results: The overall immediate remission rate was 73.3% (766/1045). First operation (p<0.001), cavernous sinus invasion on preoperative MRI(p<0.001), tumour size (p<0.001), preoperative ACTH (p=0.008), and disease duration (p=0.010) were significantly related to immediate remission on logistic univariate analysis. The AUCs of the models ranged between 0.664 and 0.743. The highest AUC, i.e., the best performance, was 0.743, which was achieved by stacking ensemble method with four factors: first operation, cavernous sinus invasion on preoperative MRI, tumour size and preoperative ACTH. Conclusion: We developed a readily available ML-based model for the preoperative prediction of immediate remission in patients with CD.

Thermal Acclimation of Foliar Carbon Metabolism in Pinus taiwanensis Along an Elevational Gradient.

Climate change could negatively alter plant ecosystems if rising temperatures exceed optimal conditions for obtaining carbon. The acclimation of plants to higher temperatures could mitigate this effect, but the potential of subtropical forests to acclimate still requires elucidation. We used space-for-time substitution to determine the photosynthetic and respiratory-temperature response curves, optimal temperature of photosynthesis (T opt), photosynthetic rate at T opt, temperature sensitivity (Q 10), and the rate of respiration at a standard temperature of 25°C (R 25) for Pinus taiwanensis at five elevations (1200, 1400, 1600, 1800, and 2000 m) in two seasons (summer and winter) in the Wuyi Mountains in China. The response of photosynthesis in P. taiwanensis leaves to temperature at the five elevations followed parabolic curves, and the response of respiration to temperature increased with temperature. T opt was higher in summer than winter at each elevation and decreased significantly with increasing elevation. Q 10 decreased significantly with increasing elevation in summer but not winter. These results showed a strong thermal acclimation of foliar photosynthesis and respiration to current temperatures across elevations and seasons, and that R 25 increased significantly with elevation and were higher in winter than summer at each elevation indicating that the global warming can decrease R 25. These results strongly suggest that this thermal acclimation will likely occur in the coming decades under climate change, so the increase in respiration rates of P. taiwanensis in response to climatic warming may be smaller than predicted and thus may not increase atmospheric CO2 concentrations.

Current situation and advances in road transportation safety among children / 中国学校卫生

Abstract@#In China, road traffic injury has been the 2nd leading cause of death for minors aging from 1 to 14 years old, has become an urgent public health problem in China. This paper introduces the current situation of children s road traffic accident injuries. Based on Haddon s model, the influencing factors of children s road traffic safety are summarized into two aspects:individual and environmental levels. Also it puts forward targeted strategies for children road safety, including improving the relevant laws and regulations system, releasing commercial insurance into children CRS evaluation criteria, improving the safety awareness level of parents, strengthening the campus traffic safety education and optimizing the road safety protection facilities, all of which could contribute to protect child safety, thus providing reference for China to improve the road traffic safety education for children.

Phospholipase C epsilon mediates cytokine cascade induced by acute disruption of epidermal permeability barrier in mice.

Disruption of epidermal barrier is an important trigger in abnormal cutaneous inflammation. Phospholipase C epsilon (PLCε), a Ras/Rap1 effector, is essential for regulating cytokines production in different types of skin inflammation. Our previous studies have demonstrated that elevated expression of PLCε participates in the psoriasis-like inflammation in PLCε overexpressing transgenic mice model, while the reduction in PLCε expression attenuates inflammatory responses in either TPA- or DNFB-induced cutaneous inflammation. Here, we determined the role of PLCε in cutaneous inflammation induced by acute abrogation of epidermal permeability barrier. In comparison to wild type controls, PLCε KO mice exhibited reduced ear swelling and infiltration of granulocytes after tape-stripping. Moreover, expression levels of pro-inflammatory cytokines (IL-1α, IL-1ß), chemokines (CXCL-1, CXCL-2, CCL20), and antimicrobial peptides (S100 proteins, MBD3) were lower in PLCε-deficient versus wild type mice. Likewise, expression levels of cytokines and chemokines were also lower in PLCε deficient keratinocytes and fibroblasts following IL-22 stimulation in vitro. Furthermore, knockdown of PLCε with its siRNA decreased expression of IL-1α, CCL20, and S100 proteins, and MBD3 in HEK cultures. Collectively, these results suggested that PLCε mediated cytokine cascade induced by acute barrier disruption. IL-22 is likely the upstream of PLCε-mediated cytokine cascade following acute barrier disruption.

"Diminishing returns" in the scaling of leaf area vs. dry mass in Wuyi Mountain bamboos, Southeast China.

PREMISE OF STUDY: Leaf area and dry mass are crucial for plant metabolic performance. The "diminishing returns" hypothesis predicts that leaf area will scale less than one with respect to leaf dry mass, indicating that the cost of light interception increases with leaf area. However, it remains unclear whether and how this scaling relationship varies among species growing in different environments. METHODS: More than 2000 measurements from five bamboo species adapted to high and low light and growing at different elevations in Wuyi Mountains, Southeast China, were used to explore how the leaf area vs. dry mass scaling relationship was affected by light and elevation. KEY RESULTS: The data indicate that (1) the normalization constants for leaf area vs. dry mass were positively but not significantly correlated with increasing leaf size and that (2) the scaling exponents remained numerically invariant among all five bamboo species, with a common slope of 0.85. Standardized major axis (SMA) analyses and comparisons of 95% confidence intervals also showed that the numerical values of the scaling exponents did not differ regardless of elevation and were similar between shaded and unshaded adapted species, whereas the numerical values of the normalization constants increased with decreasing light. CONCLUSIONS: The data collected for all five bamboo species are consistent with the "diminishing returns" hypothesis, i.e., the scaling exponents governing the leaf area vs. dry mass scaling relationship are less than one within and across species and are insensitive to light conditions or elevation.