Insights into high concentrations of particle-bound imidazoles in the background atmosphere of southern China: Potential sources and influencing factors.

Imidazoles are important constituents in atmospheric brown carbon and have gained increasing attention in the past decade. Although imidazoles have been studied widely in laboratories, the sparse field observations severely limit the understanding of imidazole's abundance and sources in the atmosphere. In this study, we measured particle-bound imidazoles and their precursors at a background forest site in the Nanling Mountains of southern China. The average concentration of imidazoles (4.17 ± 3.76 ng/m3) was found to be significantly higher than other background sites worldwide. Further analyses revealed that a majority of imidazoles (59.1%) at the site originated from secondary formation through reactions of dicarbonyls (e.g., glyoxal and methylglyoxal) and reduced nitrogen species, with relatively minor contributions from regional transport (32.8%) and biomass burning (8.1%). In addition, the key factors influencing secondary formation of imidazoles, such as relative humidity, water-soluble inorganic ions, and pH, were analyzed. Our results indicated that the secondary formation of imidazoles can be greatly enhanced under high humidity conditions, particularly during fog events. Overall, this study offers valuable insights into potential sources and influencing factors of ambient imidazoles in background atmospheres.

MES7 Modulates Seed Germination via Regulating Salicylic Acid Content in Arabidopsis.

Seed germination is an important phase transitional period of angiosperm plants during which seeds are highly sensitive to different environmental conditions. Although seed germination is under the regulation of salicylic acid (SA) and other hormones, the molecular mechanism underlying these regulations remains mysterious. In this study, we determined the expression of SA methyl esterase (MES) family genes during seed germination. We found that MES7 expression decreases significantly in imbibed seeds, and the dysfunction of MES7 decreases SA content. Furthermore, MES7 reduces and promotes seed germination under normal and salt stress conditions, respectively. The application of SA restores the seed germination deficiencies of mes7 mutants under different conditions. Taking together, our observations uncover a MeSA hydrolytic enzyme, MES7, regulates seed germination via altering SA titer under normal and abiotic stress conditions.

Genetic etiology study of four Chinese families with two nonsyndromic deaf children in succession by targeted next-generation sequencing.

BACKGROUND: Genetic components contribute significantly to the cause of hearing loss. Nonsyndromic hearing loss has been shown to have high genetic heterogeneity. For families who had given birth to two nonsyndromic deaf children in succession, it seems that their deafness was highly related to genetics. OBJECTIVES: This study aimed to disclose the genetic causes of the subjects from the four Chinese families with two nonsyndromic deaf children in succession who failed to find the genetic etiology of the hearing loss by common deafness genetic screening (GJB2, GJB3, SLC26A4, and MT-RNR1, including 20 hot variants in 4 genes). METHODS: Targeted next-generation sequencing (NGS) of 127 known deafness genes was performed in probands of four families, followed by a series of comprehensive analyses of all family members combined with a literature review of related genes. RESULTS: We identified pathogenic variants in three families including c.919-2A>G/c.1985G>A in SLC26A4; c.109G>A (p.V37I) in GJB2; and m.7505T>C in MT-TS1. Sanger sequencing confirmed that these variants segregated with the hearing impairment of each family. We also identified c.331C>T/c.625-5C>T/c.5717G>A in CDH23; c.138T>C in POU3F4 in two families, in which the pathogenicity in clinical was likely pathogenic or unknown. CONCLUSIONS: Using the NGS detection technology, we found the genetic etiology of the HL in part of deaf families. Our study provided a useful piece of information for the variant spectrum of hearing loss in Chinese families with two deaf children in succession.

[Current status of newborn deafness gene screeningin parts of China].

Objective:To analyze the current status of newborn deafness gene screening from 2016 to 2017 in multiple regions of China, and to provide a reference for further promotion and application. Method:The "newborn deafness gene screening questionnaire" was sent to 41 institutions in eastern, central and western China after expert demonstration. The survey content included status of genetic screening, screening methods, the number of screenings, and the status of positive detections from January 1st, 2016 to December 31th, 2017. Each institution returned the questionnaire, the investigator conducted data verification and quality sampling. Finally, we performed analysis of screening methods and the positive detection rate of each gene on questionnaires with complete data. Result:Forty-one questionnaires were sent out and 41 were returned, the questionnaire return rate was 100%, in which 12 questionnaires were complete. Of the 41 institutions, 15 carried newborn deafness gene screening, with a rate of 36.59%（15/41）. The highest rate was in the east（72.22%, 13/18）, and the differences among the regions were statistically significant. As for the screening methods, among 12 questionnaires with complete data, 9 variants in 4 genes and 20 variants in 4 genes accounted for the highest proportion, both with the rate of 33.33%（4/12）, followed by 15 variants in 4 genes（25%, 3/12） and 5 variants in 3 genes（8.34%, 1/12）. A total of 340, 521 neonates were included in the study, and 17, 036 were positive for screening, with a positive rate of 5.00%. Among them, the single heterozygous mutation rate of GJB2 gene was 2.43%（8269/340, 521）, the biallele mutation rate was 0.02%（56/340, 521）,the single heterozygous mutation rate of SLC26A4 gene was 1.99%（6771/340, 521）, the biallele mutation rate was 0.01%（39/340, 521）,the single heterozygous mutation rate of GJB3 gene was 0.33%（1140/340, 521）, the mitochondrial 12SrRNA gene mutation rate was 0.22%（746/340, 521） and the double-gene heterozygous mutation rate was 0.004%（15/340, 521）. Conclusion:From 2016 to 2017, the newborn deafness gene screening is more extensive in the eastern region of China than in the central and western regions. In institutions that have carried out deafness gene screening, 9 variants in 4 genes and 20 variants in 4 genes are widely used; the GJB2 gene and SLC26A4 gene mutations are the most common. The results could provide references for areas where deafness gene screening is about to be performed.

Current status of universal newborn hearing screening program at 26 institutions in China.

OBJECTIVES: The present study aimed to determine the status of a universal newborn hearing screening (UNHS) program being conducted in parts of China, by comparing differences in the program findings between 2016 and 2017, as well as across regions in China. METHODS: This study investigated a nationally representative sample of newborns from 26 provinces, autonomous regions, and municipalities in mainland China. A ''Newborn Hearing Screening Survey'' questionnaire was sent to 43 hearing screening institutions throughout China and the data were analyzed, with appropriate quality control throughout the study process. RESULTS: Twenty-six questionnaires, covering 55.88% (19/34) of the provincial administrative regions in China were appropriately completed. The overall sampling frame comprised 238,795 (year 2016) and 229,185 (year 2017) newborns, respectively. We found differences between two years, the initial screening coverage in 2017 (96.10%) was higher than that in 2016 (94.96%); the referral rate at initial screening in 2017 (9.21%) was lower than that in 2016 (10.26%); and the rescreening rate in 2017 (73.50%) was higher than that in 2016 (68.44%). We found differences across three regions, the rescreening rate were highest in West China, the referral rate at rescreening and the referral rate to diagnostic audiological assessment diagnosis were both highest, while the hearing-loss rate was lowest, in the East China in two years. Overall, 61.54% (n = 16) reported using otoacoustic emissions (OAEs), while 38.46% (n = 10) reported using OAEs in combination with automated auditory brainstem response (AABR) tests, for the initial screening. For rescreening, most sites (n = 19, 73.08%) reported using OAEs in combination with AABR, followed by OAEs only (n = 4, 15.38%) and AABR only (n = 3, 11.54%). Of the twenty-six institutions, 57.69% (n = 15) were equipped with a digital information management system for UNHS program, East China had the highest rate of it (81.82%, 9/11). CONCLUSIONS: This study indicated that implementation of a UNHS program had essentially been achieved in many regions of China under the guidance of technical specifications for newborn hearing screening. Compared with 2016, the overall quality of the UNHS program had improved in 2017 and that in East China was better than in the Midland and West China. However, national quality control of the UNHS program is still required to enhance the quality of the program and public education needs to be emphasized to improve the rescreening and reception rate.

AtXRN4 Affects the Turnover of Chosen miRNA*s in Arabidopsis.

Small RNA (sRNA) turnover is a key but poorly understood mechanism that determines the homeostasis of sRNAs. Animal XRN genes contribute the degradation of sRNAs, AtXRN2 and AtXRN3 also contribute the pri-miRNA processing and miRNA loop degradation in plants. However, the possible functions of the plant XRN genes in sRNA degradation are far from known. Here, we find that AtXRN4 contributes the turnover of plant sRNAs in Arabidopsis thaliana mainly by sRNA-seq, qRT-PCR and Northern blot. The mutation of AtXRN4 alters the sRNA profile and the accumulation of 21 nt sRNAs was increased. Some miRNA*s levels are significantly increased in xrn4 mutant plants. However, the accumulation of the primary miRNAs (pri-miRNAs) and miRNA precursors (pre-miRNAs) were generally unchanged in xrn4 mutant plants which indicates that AtXRN4 contributes the degradation of some miRNA*s. Moreover, AtXRN4 interacts with Arabidopsis Argonaute 2 (AtAGO2). This interaction takes place in Processing bodies (P-bodies). Taken together, our observations identified the interaction between XRN4 with AtAGO2 and suggested that plant XRN4 also contributes the turnover of sRNAs.

LncRNA growth arrest-specific transcript 5 targets miR-21 gene and regulates bladder cancer cell proliferation and apoptosis through PTEN.

The aim of this study was to investigate the mechanism by which growth arrest-specific transcript 5 (GAS5) regulates bladder cancer cells. Bladder cancer samples were collected and tested for experiment. Dual-luciferase reporter assay was used to verify the downstream target genes for GAS5 and miR-21. The expression level of GAS5 was decreased and that of miR-21 was increased, indicating a negative correlation between the two. Patients with high GAS5 level and low miR-21 level had relatively longer survival rates. GAS5 inhibited bladder cancer cells proliferation and promoted apoptosis, and miR-21 had the opposite effects. MiR-21 was a direct target for GAS5, whereas phosphatase and tensin homolog (PTEN) was a direct target gene of miR-21. Low expression of miR-21 could reverse the proliferative and antiapoptotic effects caused by GAS5 silencing. High levels of GAS5 and low levels of miR-21 might be associated with a higher survival rate in bladder cancer patients. GAS5 could exert antiproliferative and proapoptotic effects on bladder cancer cells through miR-21 and PTEN.

Research on life evaluation method of solder joint based on eddy current pulse thermography.

With the wide usage of electronic packaging technologies such as Ball Grid Array in electronic industry, it is necessary to maintain its quality in order to meet the demand of electronic products for function, integration, and size reduction. However, as the size of solder joints in such technology decreases, the solder joints are more and more prone to defects. To solve the life prediction problem of small-size packages having interconnections in the high-density chip, a method based on the eddy current pulsed thermography (ECPT) is put forward to study the remaining life prediction of solder joints. A 3D induction heating finite element model is established, by which the crack length of defect solder joints can be distinguished using temperature field. At the same time, the remaining life of defect solder joints can be characterized by the length of the crack. Furthermore, the experiments are carried out on solder joints whose diameter is 0.4 mm. Both simulation and experiment results verify that it is reliable and convenient to use 3D induction heating based temperature field from ECPT to evaluate the remaining life of cracks in solder joints.

Nationwide population genetic screening improves outcomes of newborn screening for hearing loss in China.

PURPOSE: The benefits of concurrent newborn hearing and genetic screening have not been statistically proven due to limited sample sizes and outcome data. To fill this gap, we analyzed outcomes of newborns with genetic screening results. METHODS: Newborns in China were screened for 20 hearing-loss-related genetic variants from 2012 to 2017. Genetic results were categorized as positive, at-risk, inconclusive, or negative. Hearing screening results, risk factors, and up-to-date hearing status were followed up via phone interviews. RESULTS: Following up 12,778 of 1.2 million genetically screened newborns revealed a higher rate of hearing loss by three months of age among referrals from the initial hearing screening (60% vs. 5.0%, P < 0.001) and a lower rate of lost-to-follow-up/documentation (5% vs. 22%, P < 0.001) in the positive group than in the inconclusive group. Importantly, genetic screening detected 13% more hearing-impaired infants than hearing screening alone and identified 2,638 (0.23% of total) newborns predisposed to preventable ototoxicity undetectable by hearing screening. CONCLUSION: Incorporating genetic screening improves the effectiveness of newborn hearing screening programs by elucidating etiologies, discerning high-risk subgroups for vigilant management, identifying additional children who may benefit from early intervention, and informing at-risk newborns and their maternal relatives of increased susceptibility to ototoxicity.

Detection of small-size solder ball defects through heat conduction analysis.

Aiming to solve the defect detection problem of a small-size solder ball in the high density chip, heat conduction analysis based on eddy current pulsed thermography is put forward to differentiate various defects. With establishing the 3D finite element model about induction heating, defects such as cracks and void can be distinguished by temperature difference resulting from heat conduction. Furthermore, the experiment of 0.4 mm-diameter solder balls with different defects is carried out to prove that crack and void solder can be distinguished. Three kinds of crack length on a gull-wing pin are selected, including 0.24 mm, 1.2 mm, and 2.16 mm, to verify that the small defect can be discriminated. Both the simulation study and experiment result show that the heat conduction analysis method is reliable and convenient.

Newborn hearing concurrent genetic screening for hearing impairment-a clinical practice in 58,397 neonates in Tianjin, China.

OBJECTIVE: Newborn hearing screening (NHS) is used worldwide due to its feasibility and cost-efficiency. However, neonates with late-onset and progressive hearing impairment will be missed by NHS. Genetic factors account for an estimated 60% of congenital profound hearing loss. Our previous cohort studies were carried out in an innovative mode, i.e. hearing concurrent genetic screening, in newborns to improve the abilities or early diagnosis and intervention for the hearing defects. In this study, we performed the first clinical practice of this mode in Tianjin city. METHODS: A large cohort of 58,397 neonates, born between December 2011 and December 2012, in 44 hospitals in Tianjin, were screened for 20 hot spot hearing loss associated mutations from GJB2, GJB3, SLC26A4 and MTRNR1(12S rRNA). The data of genetic screening results was comprehensively analyzed with newborn hearing screening (NHS) results. RESULTS: We developed an accurate, high throughput genetic screening method and applied it to a total of 58,397 newborns in Tianjin. 3225 (5.52%) infants were detected to carry at least one mutation allele in GJB2, GJB3, SLC26A4 or MTRNR1. 34 (0.58‰) infants were positive for hearing loss caused by GJB2 or SLC26A4 mutations (homozygote or compound heterozygote). 54(0.93‰) infants are heterozygous of various genes. 109(1.87‰) infants had the pathological mitochondrial DNA mutation. CONCLUSION: Accurate, comprehensive hearing loss associated genetic screening can facilitate genetic counseling and provides valuable prognostic information to affected infants. This united screening mode of this study was a promising clinical practice.

Combinative neural network and its applications.

A new approach named combinative neural network (CN) using partial least squares (PLS) analysis to modify the hidden layer in the multi-layered feed forward (MLFF) neural networks (NN) was proposed in this paper. The significant contributions of PLS in the proposed CN are to reorganize the outputs of hidden nodes such that the correlation of variables could be circumvented, to make the network meet the non-linear relationship best between the input and output data of the NN, and to eliminate the risk of over-fitting problem at the same time. The performance of the proposed approach was demonstrated through two examples, a well defined nonlinear approximation problem, and a practical nonlinear pattern classification problem with unknown relationship between the input and output data. The results were compared with those by conventional MLFF NNs. Good performance and time-saving implementation make the proposed method an attractive approach for non-linear mapping and classification.

[Clinical study on applying brainstem auditory evoked potential to monitor anesthesia depth and awaken in children].

OBJECTIVES: To study applying auditory brainstem reaction (ABR) to monitor the general anesthesia depth and awaken degree in children as an objective guide. METHODS: Forty-five infant or children patients, American Society of Anesthesiologists(ASA) graded I-II, with normal audition, were selected and divided into 3 groups (15 cases per group) to receive propofal venous anesthesia, fentanyl venous anesthesia, or isoflurane anesthesia, respectively. During anesthesia, peak latencies (PL) of I, III, V wave, and interpeak latencies (IPL) of I-III, III-V, I-V were monitored and recorded after short sound stimulation of 90 db which accumulated 1,000 times with Madsen. The changing of PL and IPL with time passing and anesthesia dosage was studied to discuss the feature of ABR in each anesthesia procedure as above. RESULTS: There is a significant positive correlation between PL and IPL of ABR waves as above and the dosage of propofol or the concentration of isoflurane. The dosage or the concentration increased, and PL and IPL prolonged. It is important of PL of wave I to reflect anesthesia degree. It is wave V with the best stability and correlation to monitor anesthesia degree. After anesthesia period or patients almost awaken, PL and IPL of some ABR waves were still more than normal values, which is detention reaction. For the fentanyl anesthesia, ABR is not sensible enough, i.e. has little correlation. CONCLUSION: The changing of PL and IPL of ABR waves could conclude anesthesia degree in children and be treated as reference of whether awaken or not in some certain, but have possibility of detention reaction.