Search

A spectral variation accompanied with flux variability is a commonly-observed phenomenon for blazars. In order to further investigate the optical spectral feature of blazars, we have collected the long-term optical V and R band data of 27 blazars (14 BL Lacs and 13 FSRQs), and calculated their optical spectral indices. The results show that the spectral indices vary with respect to the brightness for all of these blazars. In general, the optical spectrum progressively becomes flatter (or steeper), when the brightness increases. However the spectrum changes more and more slowly, until it tends to be stable. In other words, the source becomes bluer (or redder) and then gradually stabilizes when it brightens, which are briefly named the bluer-stable-when-brighter (BSWB) and redder-stable-when-brighter (RSWB) behaviors, respectively. Thirteen of the 14 BL Lacs show the BSWB behavior, with an exception of AO 0235+164. On the contrary, most of FSRQs (10 out of 13) exhibit the RSWB trend. It is confirmed that blazars follow the two universal optical spectral behaviors, namely, BSWB and RSWB. The model of two constant-spectral-index components can well explain the optical spectral features qualitatively and quantitatively. The results illustrate that the optical emission are mainly composed of two stable-color components, i.e., less variable thermal emission and high variable synchrotron radiation. And in most cases, the thermal component of BL Lacs is redder than that of synchrotron radiation, whereas FSRQs are the opposite., Comment: 9 pages, 14 figures, accepted by MNRAS

Background This study aimed to explore the trend and risk indicators for dental caries of children aged 12 years in China based on national oral health survey data in 2005 and 2015. Methods Research data were from the two latest national oral health surveys conducted in mainland China, including 30 and 31 provinces, autonomous regions, and municipalities in 2005 and 2015, respectively. Children aged 12 years were clinically examined for dental caries and dental fluorosis according to the World Health Organization criteria. Sociodemographic characteristics and oral health-related behaviours were collected using questionnaires. Multilevel zero-inflated negative binomial regression model was used to investigate the association between dental caries severity and dental fluorosis, sociodemographic characteristics, and oral health-related behaviours. Results The final analyses included 12,350 and 27,818 children surveyed in 2005 and 2015, respectively. The standardized prevalence of dental caries increased from 27.05% (95% confidence interval [CI], 24.25-28.85) in 2005 to 37.92% (95% CI, 34.94-40.90) in 2015, and the respective standardized mean decayed, missing, filled teeth (DMFT) index scores increased from 0.50 (standard deviation [SD], 1.04) to 0.83 (SD, 1.45) (P < 0.001). Fujian province had the highest increase in dental caries, followed by Liaoning, Heilongjiang, Hainan, and Yunnan. Results revealed that children who were girls, more frequently experienced dental pain, and had more recent dental visits, had significantly higher DMFT scores after adjusting for the survey year and other variables (all P < 0.05). Conclusions Dental caries of 12-year-old children in China deteriorated from 2005 to 2015, particularly in the northeast and southwest regions. Dental caries was associated with sex, dental pain, and dental service utilization.

Objective The purpose of this study was to assess the associations between the self-reported oral health-related quality of life (OHRQoL) of older Chinese people and their socio-economic status and oral health using data collected in the 4th National Oral Health Survey. Methods After multistage stratified cluster sampling, 4332 adults aged 65-74 years participated in the study. After a clinical examination, the participants completed a structured questionnaire. A Mandarin version of the General Oral Health Assessment Index (GOHAI) was included in the questionnaire. Clinical examinations were carried out using the criteria recommended by the World Health Organization. Multivariate analysis was used to evaluate the associations of the clinical and socio-demographic variables with the GOHAI scores of the participants. Results The weighted mean (SE) GOHAI score was 51.6 (0.0). Female sex and having more than 10 missing teeth, unrestored tooth spaces, more than 10 decayed teeth and a periodontal pocket ≥6 mm were negatively associated with the GOHAI score, while having a higher education level and living in the Eastern region of China were positively associated with the GOHAI score. Conclusion After adjustment for confounders, the OHRQoL of older Chinese individuals was mainly affected by untreated dental caries and the loss of teeth. Older Chinese individuals who were male, had a higher education level, were from the Eastern region, had no unrestored tooth spaces or deep periodontal pockets and had fewer decayed or missing teeth had higher GOHAI scores, indicating better OHRQoL.

Purpose LACTB, regulated by a variety of microRNAs (miRNAs), is proven to be a tumor suppressor. However, there are few reports that LACTB in colon cancer cells is regulated by miRNA. Therefore, the aim of this study was to explore the miRNAs that regulate LACTB in colon cancer. Patients and methods Data from TCGA were analyzed in starBase and GEPIA2, and Western blot and quantitative PCR (qPCR) were used to detect the expression of LACTB in colon cancer cell lines. MiRNAs targeting LACTB were predicted by MicroT-CDS, starBase, miRDB, mirDIP, and DIANA. The relationship between LACTB and miRNA was explored by dual-luciferase assay. MTT, propidium iodide (PI), Western blot, Annexin V-FITC/PI Kit, qPCR and transwell assay were used to detect the changes in cell proliferation, cell cycle, autophagy, apoptosis, epithelial-to-mesenchymal transition (EMT), cell migration, and invasiveness in colon cancer cells that overexpressed miR-1276 and/or LACTB. Results The results showed that the LACTB mRNA level was lower and the miR-1276 level was higher in colon cancer than in normal tissue. MiR-1276 inhibited the expression of LACTB. Furthermore, overexpression of miR-1276 in colon cancer cells increased proliferation, migration, invasiveness and EMT, and decreased autophagy and apoptosis. Supplementing LACTB suppressed these effects of miR-1276. Conclusion In conclusion, miR-1276, which may be a potential therapy for colon cancer, inhibits cell growth and promotes apoptosis by targeting LACTB in colon cancer cells.

Objective. Tenacissoside H (TDH) is a Chinese medicine monomer extracted from Marsdenia tenacissima extract (MTE), which has been confirmed to have antitumor effects, but its mechanism is still unclear. The aim of this study was to investigate the effect and mechanism of TDH on human colon cancer LoVo cell proliferation and migration and explore the correlation of TDH treatment with the expression of GOLPH3 and cell signaling pathways in LoVo cells. Methods. LoVo cells were treated with TDH at 0.1, 1, 10, and 100 μg/mL for 24, 48, and 72 h. The proliferation rate of LoVo cells was evaluated by MTT assay. Recombinant plasmid p-CMV-2-GOLPH3 was constructed, and p-CMV-2-GOLPH3 and p-CMV-2 empty plasmids were transfected into LoVo cells by lipofection. Western blotting was used to detect the transfection efficiency and the expression of p-p70S6K, p70S6K, β-catenin, and GOLPH3. The apoptosis rate was analyzed with Annexin V-FITC/PI double-staining method, and cell migration assessed by transwell assay. Results. TDH inhibited the proliferation of LoVo cells in a concentration-dependent manner. The IC50 of TDH treatment in LoVo cells at 24, 48, and 72 h was 40.24, 13.00, and 5.73 μg/mL, respectively. TDH treatment significantly induced apoptosis and suppressed the viability and migration of human colon cancer LoVo cells. The effect of TDH on induction of apoptosis and inhibition of migration in LoVo cells decreased significantly after activating the PI3K/AKT/mTOR and Wnt/β-catenin signaling pathways with agonists. Additionally, the expression of GOLPH3 protein downregulated significantly in LoVo cells under TDH treatment. Overexpression of the GOLPH3 gene increased the expression of key proteins in PI3K/AKT/mTOR and Wnt/β-catenin signaling pathways and blocked the antitumor activity of TDH. Conclusion. Collectively, the present results indicated that TDH can inhibit the proliferation vitality of colon cancer LoVo cells through downregulating GOLPH3 expression and activity of PI3K/AKT/mTOR and Wnt/β-catenin signaling pathways.

Asthma is one of the most common chronic inflammatory diseases of the respiratory tract. Previous studies have shown that the reduction of regulatory B cells (Bregs) can increase inflammation of the body and promote the formation of chronic airway inflammation in asthma, but the detailed mechanisms have not been fully elucidated. The intestinal flora Clostridium leptum (CL) has been reported to modulate immune regulatory cells in the body, but the specific mechanisms are not clear. This study aimed to investigate the effects of CL on the differentiation of interleukin (IL)- 10The abundances of CL and the frequencies of blood Bregs from asthmatic patients and healthy controls were compared. The house dust mite (HDM)-induced asthma model was established in mice. The effects of CL exposure and B cell infusion on Breg differentiation, T cell cytokine production, and inflammatory cell infiltration in mouse lungs were examined. Bregs were cocultured with regulatory T cells (Tregs) and CD4Compared with healthy controls, asthmatic patients had significantly reduced frequencies of blood Bregs and abundances of fecal CL, and these two parameters were positively correlated. In the asthma model, the frequencies of Bregs in lungs were significantly reduced; while the infusion of Bregs isolated from CL- supplemented mice significantly reduced airway inflammation and hyperresponsiveness. In addition, Bregs inhibited the differentiation of cocultured non-Tregs into multiple effector cells and enhanced Foxp3 expression in cocultured Tregs.Bregs contribute to the alleviation of airway inflammation, which provides insight on implementing CL-based microbial induction of Bregs in asthma therapy.

Colorectal cancer (CRC) is one of the most common malignant tumors in the digestive system, and Chinese herbal medicine plays an important role in tumor treatment. The in-depth study of auriculasin isolated from Flemingia philippinensis showed that auriculasin promoted reactive oxygen species (ROS) generation in a concentration-dependent manner; when ROS scavenger NAC was added, the effects of auriculasin in promoting ROS generation and inhibiting cell viability were blocked. Auriculasin induced CRC cell apoptosis, led to mitochondrial shrinkage, and increased the intracellular accumulation of Fe2+ and MDA. When auriculasin and NAC were added simultaneously, the levels of apoptosis, Fe2+ and MDA returned to the control group levels, indicating that auriculasin activated apoptosis and ferroptosis by inducing ROS generation. In addition, auriculasin promoted the expression of Keap1 and AIFM1, but significantly reduced the phosphorylation level of AIFM1, while NAC significantly blocked the regulation of Keap1 and AIFM1 by auriculasin, which indicates that auriculasin can also induce oxeiptosis through ROS. When Z-VAD-FMK, Ferrostatin-1, Keap1 siRNA, PGAM5 siRNA and AIFM1 siRNA were added respectively, the inhibitory effect of auriculasin on cell viability was significantly weakened, indicating that auriculasin inhibits cell viability by inducing apoptosis, ferroptosis and oxeiptosis. Auriculasin also inhibited the invasion and clone forming ability of CRC cells, while NAC blocked the above effects of auriculasin. Therefore, auriculasin can promote CRC cell apoptosis, ferroptosis and oxeiptosis by inducing ROS generation, thereby inhibiting cell viability, invasion and clone formation, indicating that auriculasin has a significant antitumor effect.

Fe3O4 is a common earth mineral, which often exists in the form of inclusions in natural diamond. It is important to explore the effects of various proportions of Fe3O4 dopants on the characteristics of synthetic diamonds as they help us to better understand the formation mechanism of natural O-containing diamonds and the state of Fe3O4 that exists inside the growth environment of natural diamonds. Diamonds were successfully synthesized using a large volume cubic high-pressure apparatus (CHPA) with an FeNi alloy catalyst doped with Fe3O4 under conditions of 6.0–6.5 GPa and 1350–1400 °C. Optical microscopy measurements indicate that as the doping ratio increases, the crystal growth is slower and there is a tendency towards cracking. The XPS spectrum confirmed that oxygen successfully enters the diamond lattice by forming CO and C–O bonds when the amount of Fe3O4 dopants is increased. We noticed that increasing the dopant ratio leads to a gradual decrease in nitrogen content in the crystals under the same pressure; however, with the same dopant, the nitrogen content decreases as the pressure increases. According to Raman spectroscopy, our synthesized crystals are high-quality sp3 structure Ib diamonds, and the full width at half maximum of the crystals gradually increases with increasing dopant concentration. Additionally, the Raman peak position shifts to the long-wave direction at higher dopant ratios. It also implies that, under the same doping conditions, the pressure increase improves the crystallinity ratio in the crystals. X-ray diffraction (XRD) of the inclusion-containing diamonds found that Fe3O4 was reduced to FeO when it was added to the FeNi catalyst.

Herein, the characteristics of heavy FeS-doped diamond crystals were studied using a China-type large volume cubic high-pressure apparatus (CHPA) with FeNi alloy as the catalyst at 6.0–6.5 GPa and 1350–1400 °C. The crystals were characterized via optical microscopy (OM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy (Raman). OM of the crystal showed that the crystals cracked when the doping ratio was increased, and an increase in pressure was beneficial to alleviate the phenomenon of cracking. The XPS spectrum of the crystal showed that S successfully enters the diamond lattice in three bonding modes, C–SO2–C6H5, C–S–SO2–C and C–S, under high concentration doping conditions. The infrared spectrum showed that the content of N in the crystal decreased with an increase in the doping ratio. The Raman spectroscopy analysis showed that the heavy FeS-doped Ib-type diamond single crystal has a high quality sp3 structure, and the full width at half maximum (FWHM) of the crystal gradually broadened as the doping ratio increased. Additionally, it showed that increasing the pressure under the same doping concentration is beneficial to increase the crystallinity of the crystal.

Acarospora impressula, A. umbilicata, Psora gresinonis, and P. himalayana are reported for the first time from China and Psora decipiens for the first time from Qinghai Province. Descriptions, illustrations, and distributions are given for each species.

One of the most topical issues regarding the recent geodynamics of Eastern Asia is identifying the boundaries of the Amurian (AM) block, it has great significance to research the relationship between the Northeast Asia and the Pacific Plate. In this study, continuous Global Positioning System (GPS) measurement data from Northeast China, Southeast Russia, the Korean Peninsula (KP) and Eastern Mongolia are used to calculate the velocity field and Euler pole. The results show that the two sides of the Tanlu fault zone have different velocity directions and Euler centers. And the movement velocity and rotation velocity of the two blocks are different. Chi-square (χ2) statistics indicate significant relative movement between the AM and KP blocks, confirming that they are generally independent and do not belong to the same block. The focal mechanism solutions and energy release indicate that Tanlu fault zone is a large dextral strike-slip fault, there are many deep-focus earthquakes, shallow-focus earthquakes and volcanic earthquakes in this fault zone, which release a lot of energy. Under the strong pushing of the Pacific plate, the KP block is forced to changed direction from SEE to SE along the Tanlu fault zone. These comprehensive calculations show that the AM and KP blocks are two mutually independent blocks, the boundary between them is the Tanlu fault zone.

Although heterotrophic nitrification-aerobic denitrification (HN-AD) is promising in nitrogen removal, it remains unclear for most HN-AD strains in physiological characteristics and metabolic mechanisms. In this study, a newly isolated strain Acinetobacter sp. Z1 converted not only inorganic nitrogen, but also organic nitrogen to N

adolescents aged 12 to 15 years based on the 4th National Oral Health Survey and to explore its associated factors.Students aged 12 to 15 years were recruited using to a multistage stratified random sampling method. All the subjects received oral examination and completed a questionnaire. Information relating to OHRQoL was collected through a Mandarin version of the child oral impacts on daily performances (Child-OIDP) questionnaire. The relationship between the Child-OIDP scores and independent variables was assessed using a Mann-Whitney U-test, Kruskal-Wallis test and a multivariate Poisson regression.A total of 89,582 subjects were included in the analysis, of whom 76.6% reported oral impacts in the last 6 months. Eating was the most affected daily performance. The results of the regression analysis showed that factors associated with adolescents' OHRQoL included sex, location of residence, region, only child status, parents' level of education, frequency of sugar consumption, self-perception of general/oral health, dental appointments in the past 12 months, oral health knowledge status, age, decayed, missing and filled teeth (DMFT) index and number of teeth with gingival bleeding.Oral impacts were common among Chinese adolescents, although most were not so severe. Eating was the most commonly affected performance. Sex, location of residence, region, only child status, parents' level of education, frequency of sugar consumption, selfperception of general/oral health status, dental appointments in the previous 12 months, oral health knowledge status, age, DMFT index and number of teeth with gingival bleeding were found to be associated with OHRQoL.

Background. Early diagnosis is very important for the clinical treatment of gastric cancer (GC) and colorectal cancer (CRC). We aimed to detect Golgi phosphoprotein 3 (GOLPH3) and evaluate its diagnostic value. Materials and Methods. Serum concentrations of GOLPH3 were detected by ELISA in 136 CRC patients, 102 GC patients, and 50 healthy controls at the Second Affiliated Hospital of Fujian Medical University from June 2016 to December 2019. Serum concentrations of CEA and CA19-9 were detected by ECLIA. Results. Serum concentrations of GOLPH3, CEA, and CA19-9 were higher in GC and CRC patients than in healthy controls ( P < 0.001 ). Serum GOLPH3 concentrations were increased in GC and CRC patients with tumors greater than 5 cm, poor differentiation, greater depth of tumor invasion, and increased lymphatic and distant metastases ( P < 0.05 ). In the GC and CRC groups, the AUCs of GOLPH3 were higher than those of CEA and CA19-9 ( P < 0.05 ), while the AUCs of the marker combination were higher than those of GOLPH3 ( P < 0.05 ), and postoperative serum GOLPH3 levels were lower than preoperative levels ( P < 0.001 ). Serum GOLPH3 concentrations in CRC patients correlated positively with CEA and CA19-9 concentrations ( P < 0.05 ). Conclusion. Serum GOLPH3 concentrations in GC and CRC patients are related to TNM stage. GOLPH3 may represent a novel biomarker for the diagnosis of GC and CRC. The combination of serum GOLPH3, CEA, and CA19-9 concentrations can improve diagnostic efficiency for GC and CRC. GOLPH3 is expected to become an indicator for the early diagnosis and evaluation of surgical effects.

Xie, C.-M., Ren, Zh.-J, Wang, Ch.-X. & Zhang, L.-L. 2020. Four species of Fuscidea new to China. – Herzogia 33: 447–454.Fuscidea asbolodes, F. elixii and F. scrupulosa are reported for the first time in Asia and F. recensa var. arcuatula is new to China. Detailed taxonomic descriptions with illustrations as well as a key to all known Chinese Fuscidea species are provided.

Comprehensive research on ethnic disparities in dental caries in China is limited. The aims of this cross-sectional study were to compare the levels of dental caries in adolescents between the Han ethnic group and ethnic minority groups in China and to explore the risk indicators for dental caries within ethnic subgroups. Data from the Fourth National Oral Health Survey in 2015, which covered all 31 province-level administrative divisions in mainland China, were used. The dental caries status in the permanent dentition of adolescents aged 12, 13, 14, and 15 y was measured using the decayed, missing, and filled teeth (DFMT) score, and sociodemographic characteristics and oral health–related behaviors were also collected. A total of 118,601 adolescents were included, with ethnic minority groups accounting for 13.15%. Of the Han and minority groups, the standardized prevalence of dental caries experience was 40.58% and 47.67%, and the mean DMFT scores were 0.97 and 1.28, respectively. According to the multivariate zero-inflated negative binomial regression analysis, the caries status of minorities was more severe than Han adolescents (adjusted prevalence rate ratio [PRR], 1.14; 95% confidence interval [CI], 1.10–1.18). This disparity was greater among adolescents who lived in rural areas, had mid-level economic status, and frequently consumed sugary beverages. After propensity score matchings, Uygur (PRR, 1.44; 95% CI, 1.25–1.67), Tibetan (PRR, 1.39; 95% CI, 1.3–1.48), and Yi (PRR, 1.24; 95% CI, 1.04–1.48) adolescents were significantly more likely to have caries than Han adolescents. Subgroup analyses revealed that gender, age, location of residence, economic status, region, consumption of sweet snacks and sugary beverages, and dental visit pattern were significantly associated with dental caries within ethnic minorities.

Background Escherichia coli are mostly commensals but also contain pathogenic lineages. It is largely unclear whether the commensal E. coli as the potential origins of pathogenic lineages may consist of monophyletic or polyphyletic populations, elucidation of which is expected to lead to novel insights into the associations of E. coli diversity with human health and diseases. Methods Using genomic sequencing and pulsed field gel electrophoresis (PFGE) techniques, we analyzed E. coli from the intestinal microbiota of three groups of healthy individuals, including preschool children, university students, and seniors of a longevity village, as well as colorectal cancer (CRC) patients, to probe the commensal E. coli populations for their diversity. Results We delineated the 2280 fresh E. coli isolates from 185 subjects into distinct genome types (genotypes) by PFGE. The genomic diversity of the sampled E. coli populations was so high that a given subject may have multiple genotypes of E. coli, with the general diversity within a host going up from preschool children through university students to seniors. Compared to the healthy subjects, the CRC patients had the lowest diversity level among their E. coli isolates. Notably, E. coli isolates from CRC patients could suppress the growth of E. coli bacteria isolated from healthy controls under nutrient-limited culture conditions. Conclusions The coexistence of multiple E. coli lineages in a host may help create and maintain a microbial environment that is beneficial to the host. As such, the low diversity of E. coli bacteria may be associated with unhealthy microenvironment in the intestine and hence facilitate the pathogenesis of diseases such as CRC.

The phenomenon of aggregation-induced emission (AIE) is inseparable from molecular aggregation and self-assembly. Therefore, the combination of AIE and supramolecular self-assembly is well-matched. AIE-guided dynamic assembly (AGDA) could effectively respond to the endogenous stimuli (such as pH, enzymes, redox molecules) and exogenous stimuli (temperature, light, ultrasound) in the disease microenvironment, so as to achieve specific imaging and diagnosis of the disease lesions. Moreover, AGDA also dynamically adjust the intramolecular motions of AIE molecules, thereby adjusting the energy dissipation pathways and realizing the switch between photodynamic therapy and photothermal therapy for superior therapeutic effects. In this review, we aim to give an overview of the constructing strategies, stimuli-responsive imaging, regulation of intramolecular motion of AGDA in recent years, which is expected to grasp the research status and striving directions of AGDA for imaging and therapy.

Background The financial burden of oral diseases is a growing concern as the medical expenses rise worldwide. The aim of this study was to investigate the dental expenditure, analyze its progressivity and horizontal inequality under the general health finance and insurance system, and identify the key social determinants of the inequality for Chinese adults. Methods A secondary analysis used the data of 13,464 adults from the 4th National Oral Health Epidemiological Survey (NOHES) in China was undertaken. The dental expenditure was collected and divided into out-of-pocket and health insurance payments. Horizontal inequality index and Kakwani index were used to analyze the horizontal inequality and progressivity, respectively. The decomposition model of the concentration index was set up to explore the associated socioeconomic determinants. Results The results showed that a mean dental expenditure per capita of Chinese adults was $20.55 (95% Confidence Interval-CI: 18.83,22.26). Among those who actually used dental service, the cost was $100.95 (95%CI: 93.22,108.68). Over 90% of dental spending was due to out-of-pocket expenses. For self-reported oral health, the horizontal inequality index was − 0.1391 and for the decayed tooth (DT), it was − 0.2252. For out-of-pocket payment, the Kakwani index was − 0.3154 and for health insurance payment it was − 0.1598. Income, residential location, educational attainment, oral hygiene practice, self-reported oral health, age difference were the main contributors to the inequality of dental expenditure. Conclusion Dental expenditure for Chinese adults was at a lower level due to underutilization. The ratio of payments of dental expenditure and utilization was disproportional, whether it was out-of-pocket or insurance payment. Individuals who were more in need of oral care showed less demand for service or not required service in time. For future policy making on oral health, it is worth the effort to further promote the awareness of the importance of oral health and utilization of dental service.

Underground utility tunnels have gradually become the focus of much research interest, but on the whole, that research remains concerned with three aspects, namely, seismic response, damage assessment, and seismic design. However, underground utility tunnels are also subject to crustal movement, which takes the forms of horizontal displacement, vertical subsidence, and ground tilt. Although the strain magnitude associated with such movement is small relative to that due to a destructive earthquake, the design life of an underground utility tunnel can be as much as a century, meaning that long-term cumulative damage cannot be ignored. Integrating the ideas of interdisciplinary research, we use geodetic data from the global positioning system (GPS), interferometric synthetic aperture radar (InSAR), and strain sensors to calculate the cumulative strain of shallow ground. The results show that the cumulative damage to an underground utility tunnel can be well inversed by using GPS and InSAR data. They also show that this cumulative damage forms a large proportion of the damage history of the utility tunnel, meaning that it should not be neglected in engineering practice. Not only is the present research a preliminary attempt to use geodetic data to calculate the cumulative damage to an underground utility tunnel, it also provides theoretical support for the safety design of underground utility tunnels.

Root nodules in peanut (Arachis hypogaea L.) could directly utilize nitrogen (N) in the atmosphere as N source, which plays an important role in the N supply in peanut. However, little is known about the mechanism of efficient N fixation by root nodule. In this study,花生根系着生根瘤,能够直接利用大气中的氮气作为氮源,在花生氮素供应中占有举足轻重的地位.而有关根瘤高效固氮的机理研究甚少.本研究在盆栽条件下,利用

Poly(hexamethylene succinate- co -hexamethylene fumarate)s (PHSF) with low hexamethylene fumarate content ( C HF , between 0 and 18 mol%) were prepared and employed to explore the effect of intersegmental interaction in crystalline lattice on the polymorphism phenomenon. Wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) results demonstrate that the crystal modification of PHSF exhibits not only C HF -dependent but also crystallization temperature ( T c ) dependent. Both high C HF and high T c benefit the formation of orthorhombic modification, while low C HF and low T c benefit the formation of monoclinic modification. More intriguingly, the specific “C C C O⋯H C C” hydrogen bonds formed between fumaryl units provide a direct way to regulate the polymorphism from perspective inside chain structure. When C HF is between 8 and 12 mol%, the crystal modification of PHSF is determined by formation of intersegmental hydrogen bonding interaction or not through varying T c . At high T c , the specific hydrogen bonds form and render the formation of orthorhombic crystal; while at low T c , only van der Waals forces remain and PHSF chains crystallize into monoclinic crystal. The content of carbonyl group belonging to fumaryl in polyester chain is a key factor for the formation of hydrogen bonds and the selection of crystal structure during crystallization. Additionally, the orthorhombic crystal shows higher equilibrium melting point than monoclinic crystal; and the monoclinic crystal can transform to orthorhombic crystal by annealing, revealing that orthorhombic crystal is more thermally stable.

A one-dimensional hydrodynamic model is developed for a magnetized plasma sheath, consisting of Maxwell electrons, q-non-extensive electrons, and thermal ions. A significant change is observed in the quantities characterizing isolated dust particles in the presence of superextensive electrons (q

To evaluate the use of oral health services, the economic burden of oral diseases and related influential factors in China.Using the multistage, stratified, equal proportion, random sampling method in the 4th National Oral Health Survey of China conducted in 2015 to 2016, residents aged 3 to 5 years, 12 to 15 years, 35 to 44 years, 55 to 64 years, and 65 to 74 years respectively were recruited, clinically examined and answered a questionnaire. Utilisation of oral health services were assessed in all the age groups and the economic burden of oral diseases in the past 12 months were assessed in the 3 to 5 years and 35 to 74 year-old groups. Chi-squared tests, t tests, correlation analysis and a one-way ANOVA were used to determine the relationships of different factors with utilisation of oral health services and the economic burden of oral diseases.In the subject groups - 3 to 5 years, 12 to 15 years and 35 to 74 years - the prevalence of the utilisation of oral health services in the past 12 months was 14.6% (5,876/40,353), 23.6% (27,936/118,592), and 20.1% (2,708/13,461), respectively. In all three groups, receiving dental treatment was the most common reason for subjects' recent dental visit. The average dental cost in the past 12 months was 403.43 CNY (median = 100) for 3 to 5-year-old children and 850.83 CNY (median = 300) for adults aged 35 to 74 years old. Area, education and annual household income per person were the socio-economic influential factors. Oral health status, oral hygiene and attitudes to and knowledge of oral health affected the utilisation of oral health services and the economic burden of oral diseases.The percentage of dental service utilisation was relatively low, and the economic burden was high. The related factors for both utilisation of oral health services and the economic burden of oral diseases included living in area, educational attainment, household income, perceived oral health status, and oral hygiene.

To assess the current periodontal status of 35 to 44-year-olds from the Chinese population and to analyse potential influence factors on periodontal disease.The data of subjects were collected from both urban and rural areas of all 31 provinces, autonomous regions and municipalities of the mainland of China, as part of the 4th National Oral Health Survey. All subjects were aged 35 to 44 years old. In total, 4,410 subjects were enrolled in the present study. Each subject was asked to undergo a professional oral examination and to fill in a questionnaire. Periodontal health status was evaluated by probe bleeding, calculus, periodontal pocket depth and clinical attachment loss. The data were analysed using the chi-square test and binary logistic regression analysis.The prevalence of probe bleeding and calculus was 87.4% and 96.7% respectively among the 35 to 44-year-old population. Prevalence of shallow pockets (4 mm ≤ PD6 mm) and deep pockets (PD ≥ 6 mm) was 45.8% and 6.9% respectively among 35 to 44-year-old people. In addition, prevalence of clinical attachment loss (CAL3 mm) was 33.2%. Gender, educational level, smoking, teeth brushing frequency, dental floss and toothpick use were found relevant to periodontal condition.Periodontal disease was highly prevalent among 35 to 44-year-old Chinese adults. Gender, educational level, smoking, teeth brushing frequency, toothpick and dental floss use could be potential influence factors of periodontal health status.

To investigate the current status and distribution of resources for oral health in China, by means of analysing national data from the National Investigation of Resources for Oral Health.The National Investigation of Resources for Oral Health in China was performed in 2015, in parallel with the 4th National Oral Health Survey of China (2015 to 2016). A structured questionnaire on resources for oral health was used to collect the data of professional institutions and stomatological/dental workforce in each province. For each province, the local Investigation Group was responsible to summarise the status and distribution of institutions with stomatological/dental departments and stomatological/dental workforce. Descriptive analysis of resources for oral health was performed to learn about the number and percentage of each category both for each province and nationally. The ratio of number of stomatological/dental workforce to population was also calculated and compared with the criteria of the World Health Organisation (WHO).There were totally 75,399 stomatological/dental departments nationally in all professional institutions in the mainland of China, most of which were set in institutions of primary health care services. Institutions of private sectors accounted for a higher proportion (69.8%) which was over two-fold compared to that of public ones (30.2%). General hospitals were the major part of hospitals with stomatological/dental departments compared with stomatological/dental specialised hospitals. Stomatological/dental clinics were the majority of institutions of primary health care services, compared to community health care service centres/stations and township health care services. Amongst all professional institutions of public health with stomatological/dental departments, 35.0% were maternal and child health care services and 11.2% were institutions for prevention and control of oral diseases. The total number of stomatological/dental workforce in the country was 314,347, among whom 171,587 (54.6%) were stomatologists/dentists. The ratio of number of stomatologists/dentists to population was 1:7,768 nationally, which was lower than the WHO standard of 1:5,000.The National Investigation of Resources for Oral Health in China exhibited the current status and distribution of resources for oral health over the country, whereas insufficiencies of stomatological/dental workforce and institutions and inequalities of their distribution were found nationally. This could provide some policy suggestions for the health authorities in China to promote oral health in the Chinese population in the future.