Engineering Co-N-Cr Cross-Interfacial Electron Bridges to Break Activity-Stability Trade-Off for Superdurable Bifunctional Single Atom Oxygen Electrocatalysts.

Atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts have exhibited encouraging oxygen reduction reaction (ORR) activity. Nevertheless, the insufficient long-term stability remains a widespread concern owing to the inevitable 2-electron byproducts, H2O2. Here, we construct Co-N-Cr cross-interfacial electron bridges (CIEBs) via the interfacial electronic coupling between Cr2O3 and Co-N-C, breaking the activity-stability trade-off. The partially occupied Cr 3d-orbitals of Co-N-Cr CIEBs induce the electron rearrangement of CoN4 sites, lowering the Co-OOH* antibonding orbital occupancy and accelerating the adsorption of intermediates. Consequently, the Co-N-Cr CIEBs suppress the two-electron ORR process and approach the apex of Sabatier volcano plot for four-electron pathway simultaneously. As a proof-of-concept, the Co-N-Cr CIEBs is synthesized by the molten salt template method, exhibiting dominant 4-electron selectively and extremely low H2O2 yield confirmed by Damjanovic kinetic analysis. The Co-N-Cr CIEBs demonstrates impressive bifunctional oxygen catalytic activity (▵E=0.70 V) and breakthrough durability including 100 % current retention after 10 h continuous operation and cycling performance over 1500 h for Zn-air battery. The hybrid interfacial configuration and the understanding of the electronic coupling mechanism reported here could shed new light on the design of superdurable M-N-C catalysts.

d-Orbital Electron Delocalization Realized by Axial Fe4 C Atomic Clusters Delivers High-Performance Fe-N-C Catalysts for Oxygen Reduction Reaction.

Fe-N-C catalyst for oxygen reduction reaction (ORR) has been considered as the most promising nonprecious metal catalyst due to its comparable catalytic performance to Pt in proton exchange membrane fuel cells (PEMFCs). The active centers of Fe-pyrrolic N4 have been proven to be extremely active for ORR. However, forming a stable Fe-pyrrolic N4 structure is a huge challenge. Here, a Cyan-Fe-N-C catalyst with Fe-pyrrolic N4 as the intrinsic active center is constructed with the help of axial Fe4 C atomic clusters, which shows a half-wave potential of up to 0.836 V (vs. RHE) in the acid environment. More remarkably, it delivers a high power density of 870 and 478 mW cm-2 at 1.0 bar in H2 -O2 and H2 -Air fuel cells, respectively. According to theoretical calculation and in situ spectroscopy, the axial Fe4 C can provide strong electronic perturbation to Fe-N4 active centers, leading to the d-orbital electron delocalization of Fe and forming the Fe-pyrrolic N4 bond with high charge distribution, which stabilizes the Fe-pyrrolic N4 structure and optimizes the OH* adsorption during the catalytic process. This work proposes a new strategy to adjust the electronic structure of single-atom catalysts based on the strong interaction between single atoms and atomic clusters.

Fe-N-C catalysts decorated with oxygen vacancies-rich CeOx to increase oxygen reduction performance for Zn-air batteries.

Platinum group metal (PGM)-free catalysts represented by nitrogen and iron co-doped carbon (Fe-N-C) catalysts are desirable and critical for metal-air batteries, but challenges still exist in performance and stability. Here, cerium oxides (CeOx) are incorporated into a two-dimensional Fe-N-C catalyst (FeNC-Ce-950) via a host-guest strategy. The Ce4+/Ce3+ redox system creates a large number of oxygen vacancies for rapid O2 adsorption to accelerate the kinetics of oxygen reduction reaction (ORR). Consequently, the as-synthesized FeNC-Ce-950 catalyst exhibits a half-wave potential (E1/2) of 0.921 V and negligible decay (<2 mV for ΔE1/2) after 5,000 accelerated durability cycles, significantly outperforming most of ORR catalysts reported in recent years and precious metal counterparts. When applied in a zinc-air battery, it demonstrates a peak power density of 175 mW cm-2 and a specific capacity of 757 mAh gZn-1. This study also provides a reference for the exploration of Fe-N-C catalysts decorated with variable valence metal oxides.

Nutritional complexity in children with ADHD related morbidities in China: A cross-sectional study.

BACKGROUND AND OBJECTIVES: To assess the general and nutritional health of children with attention deficit/ hyperactivity disorder (ADHD). METHODS AND STUDY DESIGN: The National Multicenter Sleep Research Database for 23791 school-age children in grades 1-6 from 9 cities in China was accessed. Children with a specialist diagnosis of ADHD or not (non-ADHD) in 2005 were studied. National anthropometric growth standards for children aged 2-18 years classified children as underweight, wasted, stunted (short stature presumed nutritional), or overweight/obesity. Independent variables were preterm birth, sleep quality and prior disease and ADHD was the dependent variable. Binary logistic regression models were developed along with interaction analyses for associated disorder or disease on overweight/obesity, and stunted. RESULTS: Some 18731 records were analyzed for 808 children with ADHD. The comparative prevalences for ADHD with non-ADHD children were stunted 9.8% vs 5.9% (p<0.001) and overweight/ obesity (32.6% vs 29.6%, p=0.002) respectively. ADHD boys were more often underweight (7.5% vs 5.3%, p=0.027), but not in girls. ADHD likelihood Odds Ratios, ORs (with 95%CI) were for premature birth 1.838, (1.393-2.423), allergic diseases 1.915 (1.526-2.399), otitis media 1.54 (1.118- 2.146), tonsillar or adenoid hypertrophy1.662 (1.348-2.050), gastroesophageal reflux 3.008(1.792-1.792-5.049), and sleep disorder 2.201(1.847-2.623) were ADHD risk factors. Only poor sleep quality and ADHD exhibited an interaction for stunted with OR=0.409 (0.233-0.719). CONCLUSIONS: Compromised and complex nutritional health in ADHD children challenges clinical nutrition with a range of health problems, albeit coherent with the needed nutritional emphasis in the 'first 1000 days'.

Neuropsychological Profile Related with Executive Function of Chinese Preschoolers with Attention-Deficit/Hyperactivity Disorder: Neuropsychological Measures and Behavior Rating Scale of Executive Function-Preschool Version.

BACKGROUND:: Previous studies have found that schoolchildren with attention-deficit/hyperactivity disorder (ADHD) showed difficulties in neuropsychological function. This study aimed to assess neuropsychological function in Chinese preschoolers with ADHD using broad neuropsychological measures and rating scales and to test whether the pattern and severity of neuropsychological weakness differed among ADHD presentations in preschool children. METHODS:: The 226 preschoolers (163 with ADHD and 63 controls) with the age of 4-5 years were included and assessed using the Behavior Rating Scale of Executive Function-Preschool Version (BRIEF-P) and a series of tests to investigate neuropsychological function. RESULTS: Preschoolers with ADHD showed higher scores in all domains of the BRIEF-P (inhibition: 30.64 ± 5.78 vs.20.69 ± 3.86, P < 0.001; shift: 13.40 ± 3.03 vs.12.41 ± 2.79, P = 0.039; emotional control:15.10 ± 3.53 vs.12.20 ± 2.46, P < 0.001; working memory: 28.41 ± 4.99 vs.20.95 ± 4.60, P < 0.001; plan/organize: 17.04 ± 3.30 vs.13.29 ± 2.40, P < 0.001) and lower scores of Statue (23.18 ± 7.84 vs.28.27 ± 3.18, P = 0.001), Word Generation (15.22 ± 6.52 vs.19.53 ± 7.69, P = 0.025), Comprehension of Instructions (14.00 ± 4.44 vs.17.02 ± 3.39, P = 0.016), Visuomotor Precision (P < 0.050), Toy delay (P = 0.048), and Matrices tasks (P = 0.011), compared with normal control. In terms of the differences among ADHD subtypes, all ADHD presentations had higher scores in several domains of the BRIEF-P (P < 0.001), and the ADHD-combined symptoms (ADHD-C) group had the poorest ratings on inhibition and the ability to Plan/Organize. For neuropsychological measures, the results suggested that the ADHD-C group had poorer performances than the ADHD-predominantly inattentive symptoms (ADHD-I) group on Statue tasks (F = 7.34, η2 = 0.12, P < 0.001). Furthermore, the ADHD-hyperactive/impulsive symptoms group had significantly poorer performances compared to the ADHD-C group in the Block Construction task (F = 4.89, η2 = 0.067, P = 0.003). However, no significant group differences were found between the ADHD-I group and normal control. CONCLUSION:: Based on the combined evaluation of performance-based neuropsychological tests and the BRIEF-P, preschoolers with ADHD show difficulties of neuropsychological function in many aspects.

Parent-adolescent interaction and risk of adolescent internet addiction: a population-based study in Shanghai.

BACKGROUND: Family-based intervention is essential for adolescents with behavioral problems. However, limited data are available on the relationship between family-based factors and adolescent internet addiction (AIA). We aimed to examine this relationship using a representative sample of Shanghai adolescents. METHODS: In October 2007, a total of 5122 adolescents were investigated from 16 high schools via stratified-random sampling in Shanghai. Self-reported and anonymous questionnaires were used to assess parent-adolescent interaction and family environments. AIA was assessed by DRM-52 Scale, developed from Young's Internet-addiction Scale, using seven subscales to evaluate psychological symptoms of AIA. RESULTS: Adjusting for adolescents' ages, genders, socio-economic status, school performances and levels of the consumption expenditure, strong parental disapproval of internet-use was associated with AIA (vs. parental approval, OR = 2.20, 95% CI: 1.24-3.91). Worse mother-adolescent relationships were more significantly associated with AIA (OR = 3.79, 95% CI: 2.22-6.48) than worse father-adolescent relationships (OR = 1.76, 95% CI: 1.10-2.80). Marital status of "married-but-separated" and family structure of "left-behind adolescents" were associated with symptoms of some subscales. When having high monthly allowance, resident students tended to develop AIA but commuter students did not. Family social-economic status was not associated with the development of AIA. CONCLUSIONS: The quality of parent-adolescent relationship/communication was closely associated with the development of AIA, and maternal factors were more significantly associated with development of AIA than paternal factors. Family social-economic status moderated adolescent internet-use levels but not the development of AIA.

Personal characteristics related to the risk of adolescent internet addiction: a survey in Shanghai, China.

BACKGROUND: Paralleling the rapid growth in computers and internet connections, adolescent internet addiction (AIA) is becoming an increasingly serious problem, especially in developing countries. This study aims to explore the prevalence of AIA and associated symptoms in a large population-based sample in Shanghai and identify potential predictors related to personal characteristics. METHODS: In 2007, 5,122 adolescents were randomly chosen from 16 high schools of different school types (junior, senior key, senior ordinary and senior vocational) in Shanghai with stratified-random sampling. Each student completed a self-administered and anonymous questionnaire that included DRM 52 Scale of Internet-use. The DRM 52 Scale was adapted for use in Shanghai from Young's Internet Addiction Scale and contained 7 subscales related to psychological symptoms of AIA. Multiple linear regression and logistic regression were both used to analyze the data. RESULTS: Of the 5,122 students, 449 (8.8%) were identified as internet addicts. Although adolescents who had bad (vs. good) academic achievement had lower levels of internet-use (p < 0.0001), they were more likely to develop AIA (odds ratio 4.79, 95% CI: 2.51-9.73, p < 0.0001) and have psychological symptoms in 6 of the 7 subscales (not in Time-consuming subscale). The likelihood of AIA was higher among those adolescents who were male, senior high school students, or had monthly spending >100 RMB (all p-values <0.05). Adolescents tended to develop AIA and show symptoms in all subscales when they spent more hours online weekly (however, more internet addicts overused internet on weekends than on weekdays, p < 0.0001) or when they used the internet mainly for playing games or real-time chatting. CONCLUSIONS: This study provides evidence that adolescent personal factors play key roles in inducing AIA. Adolescents having aforementioned personal characteristics and online behaviors are at high-risk of developing AIA that may compound different psychological symptoms associated with AIA. Spending excessive time online is not in itself a defining symptom of AIA. More attention is needed on adolescent excessive weekend internet-use in prevention of potential internet addicts.

[Clinical and genetic study of a case with Smith-Magenis syndrome].

OBJECTIVE: To explore the clinical feature and genetic diagnosis for Smith-Magenis syndrome (SMS). METHOD: The clinical data, including craniofacial anomalies, physical and mental status were analyzed. Routine and high resolution G-banding was performed to analyze the karyotype of the patient and her parents, and array comparative genomic hybridization (array CGH) was used to detect small chromosome anomaly. RESULT: A-two-year old girl was sent to our clinic for mental retardation and cardiac malformation. Some sleep problems were reported by parents, including difficulties falling asleep, shortened sleep cycles. She also had some neurobehavioral symptoms including hyperactivity and self-injurious behaviors head-banging. She had distinctive craniofacial features including low hairline, frontal bossing, a broad face, broad nasal bridge, a tented upper lip, prognathism, low-set ears and high-vaulted arch. She had moderate mental retardation. Cardiac findings included ventricular septal defect, atrial septal defect, overriding aorta and pulmonary hypertension. Primary ventriculomegaly was seen in magnetic resonance imaging (MRI). Routine karyotype analysis showed a karyotype of 46, XX. However, high resolution karyotype analysis showed a suspected partial deletion of the short arm of chromosome 17. Array comparative genomic hybridization (array CGH) finely mapped the deletion to a 3.8 Mb region on 17p11.2. The molecular karyotype was then ascertained as 46, XX.arr17p11.2(16543655-20374751)×1dn. The parents had normal karyotypes. CONCLUSION: Smith-Magenis syndrome is a multisystem disorder characterized by developmental delay and mental retardation, distinctive craniofacial features, sleep disturbance and behavioral problems. Array comparative genomic hybridization (array CGH) finely mapped the deletion on 17p11.2.

[Internet addiction among Shanghai adolescents: prevalence and epidemiological features].

OBJECTIVE: To study the prevalence of internet use and internet addiction in adolescents of Shanghai. METHOD: From September to October 2007, a total of 5135 adolescents from 16 middle schools of 6 districts of Shanghai took part in the epidemiological study by a cross-sectional survey and 5123 adolescents finally enrolled in the study. A questionnaire of "DRM Adolescent Internet Use 52 Scale" was administrated to investigate the prevalence of internet use and internet addiction in adolescents of Shanghai. On this scale of 5-point rating, the scale includes seven parts of contents as tolerance, abstinence reaction, planning ability, self-control ability, whenness, sociability and hazard. RESULTS: The rate of internet use among the surveyed adolescents was 94.32% (4673/5123), among which the incidence rate of internet addiction was 8.78% (450/5123). Boys, senior middle-school students were more susceptible to internet addiction than girls and junior middle-school students (male scores 122.42+/-43.46, female scores 116.92+/-38.10, F=23.22, P=0.00; senior middle-school students 125.24+/-39.02, junior middle-school students 110.30+/-42.35, F=164.68, P=0.00). Students from vocational senior middle-school were most susceptible (junior middle-school students 110.30+/-42.35, ordinary senior middle-school students 122.83+/-40.99, key senior middle-school students 120.05+/-37.87, vocational senior middle-school students 133.37+/-36.84, F=34.44, P=0.00). The 2nd grade students of senior middle-school have the highest risk for internet-addiction. CONCLUSION: The prevalence of internet use and internet addiction in adolescents of Shanghai should be comparatively high in China, which indicates that great attention should be paid to the prevention and control.

[Association between vitamin D receptor gene polymorphism and vitamin D deficiency rickets].

OBJECTIVE: To explore the genetic susceptibility of children to vitamin D deficiency rickets through studying the association between Vitamin D receptor (VDR) gene polymorphism and vitamin D deficiency rickets. METHODS: One hundred and fifty-nine children (100 boys and 59 girls, aged 0 to 2 years), with new-onset vitamin D deficiency rickets were enrolled. The patients sampled from a community of Jiamusi City, Heilongjiang Province. Seventy-eight healthy age-matched children (46 boys and 32 girls) were used as the controls. VDR gene polymorphism (cleaved by restriction endonuclease Fok I) was analyzed by polymerase chase reaction-restriction fragment length polymorphism (PCR-RFLP). The frequencies of the VDR genotype and allele were compared between the two groups. RESULTS: The frequencies of FF, Ff and ff genotypes were 37%, 51% and 12% in the Rickets group, and 18%, 55% and 27% in the Control group. A significant difference was found in the frequency distribution of the VDR genotype between the two groups (chi(2)(0.01(2))=9.210, chi(2)=13.3880, P < 0.01). In the Rickets group, f allele frequency was lower (37% vs 54%), while the F allele was more common than the Control group (63% vs 46%). CONCLUSIONS: There is an association between the VDR gene Fok I polymorphism and vitamin D deficiency rickets. The individuals with the F allele are more susceptible to vitamin D deficiency rickets.

[Anxiety state and its related factors in Shanghai high school students].

OBJECTIVE: To investigate the anxiety state in high school students and related factors in order to get reasonable suggestions for prevention. METHODS: The mental health test (MHT) for high school students, and the living environmental and parental style were used in this study. RESULTS: MHT served as an assessment scale of anxiety. The efficiency sample was 3,050, aged 11 to 18 years old. The level of total anxiety and its each contents was low to moderate (0.24 to 0.54). The percentage of moderate to high of total anxiety was 16.7%, the percentage of moderate to high of each anxiety aspects were 8.8%-21.8%. The mostly high aspects were self-blame, schooling anxiety, social anxiety and over sensitiveness. In general, the girls' anxiety level was higher than boys', but the boys' lonely feeling was higher than the girls'. The total score of anxiety was decreased with age. Except of the over sensitiveness, the decrease tendency of each anxiety contents was significant in boys. For girls, the lonely feeling was deceased and the over sensitiveness increased with age. The age of fifteen seems as a significant changing age. The related disadvantage factors of students' anxiety were: the low education level, the parents' anxiety and depression characters, the authoritarian or neglecting parental style, the often contradiction parental styles between mother and father, parents often quarrel, the experience of often being scalded and physical punishment, lacking in care of others when in difficulties. CONCLUSIONS: The schooling pressure should be decreased to an appropriate level. The students' self-confidence and social ability should be emphasized. Good family environments and the support outside the family should be quite important for adolescents' mental health, these factors might decrease the adolescents' anxiety.