Lock-in thermography provides a fast, low-cost, and accurate non-destructive testing for subsurface defect detection in materials. However, there is serious sensor noise and background interference ...presented in the infrared images captured by lock-in thermography. In this paper, we set up lock-in thermography experiments to analyze the characteristics of sensor noise and background interference. Based on their different characteristics, we design a two-stage CNN model for the joint removal of sensor noise and background interference. This model consists of a number of multi-direction feature extraction blocks (MDFEBs) to extract local features in different directions for pixel-level sensor noise removal, and an encoder–decoder architecture with large receptive fields to extract global features for background interference correction. Experimental results demonstrate that our proposed method outperforms the well-established infrared image denoising and non-uniform background correction techniques on specimens made of different materials and at various excitation frequencies. The proposed two-stage CNN model provides high-quality input of infrared images for the following subsurface defect detection task in lock-in thermography.
Citrus bark cracking viroid (CBCVd), previously called Citrus viroid IV, belongs to the genus Cocadviroid within the family Pospiviroidae. CBCVd has been identified as an important causative agent in ...citrus and hops. In this study, we obtained the full-length genomes of different variants of all detected citrus viroids from Pakistan through transcriptome sequencing. Different CBCVd variants were first found in Pakistan. These newly discovered Pakistani CBCVd variants were provisionally called "CBCVd-LSS" for their low sequence similarity (80.9%-88.9%) with the CBCVd RefSeq sequence (NC_003539). The two most predominant CBCVd sequences from Pakistan had the closest identity, 90.6% and 87.9%, with two CBCVd sequences isolated from hops. Identification and molecular characterization of CBCVd from citrus in Pakistan and China were also reported. The length of CBCVd from China ranged from 282 to 286 nucleotides, while that of the one from Pakistan ranged from 273 to 277 nucleotides. Based on genetic diversity and phylogenetic analysis, two main CBCVd clades were identified. CBCVd sequences from Pakistan, China, and other countries were further divided into six sub-clades. Sequence alignment revealed some nucleotide changes between these sub-clades, and analysis indicated that several mutations could significantly affect the primary and secondary structure of the viroid. Our results indicated that the CBCVd sequences from Pakistan and China were significantly different with respect to genome and secondary structure and Pakistan might be one of the independent geographical origins of CBCVd worldwide.
To investigate the association and effects of air pollution level on male semen quality in urban and rural areas, this study examines the outdoor concentrations of particulate matter (PM10), sulfur ...dioxide (SO2), nitrous dioxide (NO2) and semen quality outcomes for 1346 volunteers in both urban and rural areas in Chongqing, China. We found the urban area has a higher pollution level than the rural area, contrasted with better semen quality in the rural residents, especially for sperm morphology and computer assistant semen analysis (CASA) motility parameters. A multivariate linear regression analysis demonstrates that concentrations of PM10, SO2, and NO2 significantly and negatively are associated with normal sperm morphology percentage (P < 0.001) and sperm kinetic parameters. In conclusion, exposure to higher concentrations of PM10, SO2, and NO2 in urban ambient air may account for worse semen quality in urban males.
•We investigate the distributions of PM10, SO2 and NO2 in urban and rural areas in Chongqing, China.•We explore the associations of air pollution and male semen quality.•The concentrations of PM10, SO2, and NO2 are significantly higher in urban areas.•Median values of some semen quality parameters in rural male were higher than urban male.•PM10, SO2, and NO2 were negatively associated with semen quality parameters.
Air pollution is higher in the urban area while there is better semen quality in rural males. Polluted air may thus account for worse semen quality in urban males.
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Due to the p-π conjugative effect between the nitrogen atom of the amide and the carbonyl, the amide carbonyl has much low reactivity and the Schiff base reaction between the amide ...and amine usually did not take place, but after the amide was polymerized, it's quite different. Herein, benzene-1,3,5-triyltris((9H-carbazol-9-yl) methanone) (HTCZ) is not able to have the Schiff base reaction with melamine. Surprisingly, after HTCZ was polymerized according to the Friedel-Crafts reaction, the resultant polymer PHTCZ-1 performed the Schiff base reaction with melamine successfully, and a kind of novel N-rich porous organic polymers, namely, PHTCZ-1-MA was successfully synthesized. Moreover, PHTCZ-1-MA owned much higher Brunauer-Emmett-Teller surface area (613 m2·g−1) and pore volume (0.57 cm3·g−1) with very high nitrogen content (42.39 wt%). The theoretical calculation showed that the positive charge of the carbonyl carbon increased by 18% after the polymerization, which greatly improved the reactivity of the carbonyl. Because of this amazing change, PHTCZ-1-MA was proven to be an excellent adsorbent for CO2 capture (180 mg·g−1 at 273 K and 1.0 bar) and mercury(II) adsorption (335 mg·g−1 at 273 K). This study makes the impossibility possible and provides a unique synthesis strategy for the fabrication of a kind of N-rich porous organic polymers.
Suicide is a major public health issue in China. Studies of suicide risk factors have reported both inconsistent and inconclusive results. This review aimed to determine suicide risk factors in ...China.
Medline/PubMed, EMBASE, CNKI (China National Knowledge Infrastructure) and VIP (Chinese Journal of Science and Technology of VIP) were searched for relevant reports. Two investigators independently assessed the eligibility of identified studies and extracted data. Pooled odds ratios (and 95% confidence intervals) were calculated for each factor with Revman 5.0.
Forty-four studies with 192,362 subjects were included. The pooled results indicated that mood disorders and stressful life events (physical illness, suicide of relatives) increased the risk of suicide ideation among the entire population. Socio-family environment (single or remarried parent, study pressure and academic achievement) and unhealthy behaviors (smoking, alcohol drinking, and drug use) were risk factors for suicide ideation among youth. Unhealthy behaviors (smoking and alcohol drinking), mood disorders, and stressful life events (suicide of relatives) were the main risk factors for attempted suicide. Persons living in rural areas, and those with lower education, mood disorders, and/or a history of negative life events had a higher risk of completed suicide. In China, before 2000, females had a significantly higher rate of completed suicide than males, while after 2000, no significant gender difference was found.
Socio-family environment, lifestyle, life events and psychiatric/psychological factors are associated with suicidal behaviors in China. Further case-control or cohort studies are needed to better understand suicide behaviors in China. Meanwhile, there is an urgent need for comprehensive studies of suicide interventions among high-risk populations.
Nitrogen (N), one of the most important plant nutrients, plays crucial roles in multiple plant developmental processes. Spikelets are the primary sink tissues during reproductive growth, and N ...deficiency can cause floral abortion. However, the roles of N nutrition in meiosis, the crucial step in plant sexual reproduction, are poorly understood. Here, we identified an N-dependent meiotic entrance mutant with loss of function of ELECTRON TRANSFER FLAVOPROTEIN SUBUNIT β (ETFβ) in rice (Oryza sativa). etfβ displayed meiosis initiation defects, excessive accumulation of branched-chain amino acids (BCAAs) and decrease in total N contents in spikelets under N starvation, which were rescued by applying excess exogenous inorganic N. Under N starvation, ETFβ, through its involvement in BCAA catabolism, promotes N reutilization and contributes to meeting N demands of spikelets, highlighting the impact of N nutrition on meiosis initiation. We conclude that N nutrition contributes to plant fertility by affecting meiosis initiation.
Deoxynivalenol (DON) poses a serious global food safety risk due to its high toxicity and contamination rate. It disrupts the intestinal epithelial barrier, allowing exogenous toxins to enter the ...circulation and resulting in sepsis and systemic toxicity. In this research, 32 male Kunming mice and Porcine Small Intestinal Epithelial (IPEC-J2) cells were treated with DON at 0–4.8 mg/kg (7 d) and 0–12 μM (24 h), respectively. Histopathological results revealed that DON disrupted the intestinal epithelial barrier, causing apoptosis and tight junction (TJ) injury. Immunofluorescence and protein expression results showed that DON-induced p53-dependent mitochondrial pathway apoptosis and fibrillar actin (F-actin)-associated TJ injury and that the RhoA/ROCK pathway were activated in mice jejunal tissue and IPEC-J2 cells. Pretreatment with RhoA or ROCK inhibitors (Rosin or Y-27632) maintained DON-induced apoptosis and F-actin-associated TJ injury in IPEC-J2 cells. Thus, DON induces damage to the intestinal epithelial barrier through the RhoA/ROCK pathway-mediated apoptosis and F-actin-associated TJ disruption.
The Somatosensory Amplification Scale (SSAS) was designed to measure individual’s tendency to experience visceral and somatic sensations as unusually intense, disturbing and alarming. In this study, ...we aimed to investigate the reliability and validity of the SSAS in the Chinese general population, as well as the mediating effect of somatosensory amplification in the relationship between alexithymia and somatization. A total of 386 healthy adults were enrolled in this study. Participants completed the Chinese versions of the Somatosensory Amplification Scale (SSAS-C), the somatization subscale of the Symptom Check List 90 (SCL-90 som), the Toronto Alexithymia Scale (TAS-20), and the Short form Health Anxiety Inventory (SHAI). One hundred and thirty-three participants were randomly selected to complete the SSAS-C again two weeks after the initial assessment. The reliability and validity of the SSAS-C were analyzed. Confirmatory factor analysis showed that the one-factor model achieved adequate model fits; one item was deleted due to low factor loading. The revised SSAS-C showed good internal consistency and test-retest reliability. The SSAS-C scores correlated positively with the scores of SCL-90 som, TAS-20 and the SHAI, showing good convergent validity. In addition, somatosensory amplification mediated the association between alexithymia and somatization. The Chinese version of SSAS has acceptable reliability and validity for the general population. In addition, alexithymia may increase somatization through higher somatosensory amplification.
Low Ni alumina-forming austenitic (AFA) heat-resistant steel is an advanced high-temperature stainless steel with reduced cost, good machinability, high-temperature creep strength, and ...high-temperature corrosion resistance. Using the First-principles approach, this study examined the effect of Mn content on austenite stability and mechanical properties at the atomic level. Adding Mn to low Ni-AFA steel increases the unit cell volume with an accompanying increase in the absolute value of formation energy; the austenite formed more easily. The austenitic matrix binding energy decreases and remains negative, indicating austenite stability. As the Mn content increases from 3.2 to 12.8 wt%, the system's bulk modulus (B) rises significantly, and the shear modulus (G) falls. In addition, the system's strength and hardness decrease, and the Poisson ratio of the austenite matrix increases with improved elasticity; the system has excellent plasticity with an increase in the B/G. For the Fe
-Cr
-Ni
-Al
system, with the increase of Mn content, the electron density distribution between the atoms is relatively uniform, and the electrons around the Mn atoms are slightly sparse, which will slightly reduce the structural stability of the matrix. The experiment demonstrated the matrix maintains the austenitic structure when adding 3.2-12.8 wt% Mn elements to low Ni-AFA steel. At an Mn content of 8 wt%, the overall mechanical properties of the high-Mn AFA steel are optimal, with a tensile strength of 581.64 MPa, a hardness of 186.17 HV, and an elongation of 39%.
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