[Labor progression characteristics of primiparous term singleton pregnant women complicated with adenomyosis].

Objective: To analyze the labor progression characteristics of primiparous term singleton pregnant women with adenomyosis. Methods: From April 2014 to May 2021, pregnant women underwent regular antenatal examination in Peking University Third Hospital were enrolled in this retrospective study, 109 primiparous term pregnant women with adenomyosis who underwent singleton, primipara, cephalic and vaginal delivery were referred as the adenomyosis group, while 109 pregnant women without adenomyosis primiparous term pregnant women at the same time were referred as the control group. The general clinical information, labor process intervention, pregnancy outcomes and labor course time of the two groups were analyzed. Results: (1) General clinical conditions: the pre-pregnancy uterine volume of the adenomyosis group was larger than that of the control group [(66.8±23.7) vs (41.4±13.1) cm3, P<0.05]. The proportion of assisted reproductive pregnancy and endometriosis in the adenomyosis group were higher than those in the control group [31.2% (34/109) vs 7.3% (8/109); 31.2% (34/109) vs 5.5% (6/109); all P<0.05]. There were no significant differences in maternal age, gestational age at delivery, pre-pregnancy body mass index, gestational weight gain, gravidity, incidence of pregnancy complications (gestational diabetes mellitus, pre-eclampsia and thyroid diseases) and premature rupture of membranes between the two groups (all P>0.05). (2) Labor process intervention and maternal and fetal outcomes: postpartum hemorrhage was higher in the adenomyosis group than the control group (median: 300 vs 260 ml, P=0.018). There were no significant differences in the proportion of labor onset, use of oxytocin, artificial rupture of membranes, perineal laceration Ⅲ and above, episiotomy, newborn weight and 1-minute Apgar score between the two groups (all P>0.05). (3) Time of labor process: there were no significant differences between the two groups in the time required for the first stage, third stage, total stage and cervical dilation 0-1, 1-2, 2-3, 3-4, 4-5, 5-6, 6-7 cm (all P>0.05). The time required for cervical dilation 7-8, 8-9, 9-10 cm and the second stage of labor in adenomyosis group (median: 20, 18, 15 and 12 minutes, respectively) were shorter than those of the control group (median: 23, 23, 23 and 26 minutes, respectively), and the differences were statistically significant (all P<0.05). (4) The effect of endometriosis on labor: there was no significant difference in the effect of endometriosis on labor in adenomyosis group (P>0.05). Conclusions: The labor process of primiparous term pregnant women with adenomyosis is significantly accelerated after the cervical dilatation for 7 cm, which should be closely observed. The third stage of labor course is managed aggressively with drugs to prevent postpartum hemorrhage.

[Application of mathematical models of infectious diseases in the evaluation of COVID-19 transmission risk at mass gatherings].

The SARS-CoV-2 Omicron variant is rampant in Europe and the United States, and the Delta variant has caused several small-scale outbreaks in China. It is particularly important to simulate the transmission risk of novel coronavirus pneumonia (COVID-19) during large-scale events, so as to ensure a good preparation of personnel, materials, isolation sites and other support work in advance. Taking the Beijing 2022 Winter Olympic Games as an example, this study introduces the use of mathematical models to simulate the entry risks, closed-loop risks and prevention and control measures of athletes, officials and other stakeholders of the Olympic Games. In the simulation results on January 19, 2022, the estimated number of Olympic Games-related infections who were identified at borders was 357 (95%CI: 153-568) and the observed number was 323. The estimated number of "seed" cases that entered the closed-loop of Olympics Games was 195 (95%CI: 43-335), and the observed number of cases in the closed-loop was 212. This study demonstrates the important role of mathematical models of infectious diseases in the pragmatic application of preventive medicine and public health.

[Detection of drug resistance genes of mycobacterium tuberculosis by rolling circle amplification technique with multicolor fluorescent probes].

The aim of this study was to construct a simple, rapid and ultra-sensitive optical biosensing technique based on rolling circle amplification (RCA), and to apply it to multiple detection of drug-resistant genes of mycobacterium tuberculosis. The common mutation sites of isoniazid, rifampicin and streptomycin resistance genes are katG315 (AGC➝ACC), rpoB531 (CAC➝TAC) and rpsL43 (AAG➝AGG). For these three gene sites, from February 2020 to May 2021, in the Department of Laboratory Medicine of the First Affiliated Hospital of Army Military Medical University, the padlock probe (PLP), primers and capture probes were designed. And a solid-phase RCA constant temperature amplification reaction system based on magnetic beads was constructed and the experimental parameters were optimized. The RCA products were accurately captured by the multicolor fluorescent probes (Cy3/Cy5/ROX), and the single-tube multiple detection of three mutation genes was realized. The sensitivity, specificity and linear range of this method were further verified. The results showed that the response range of katG315 in the same reaction system ranged from 1.0 pmol/L to 0.1 nmol/L. The response range of rpoB531 and rpsL43 ranged from 1.0 pmol/L to 50.0 pmol/L and 1.0 pmol/L to 20.0 pmol/L, and the method had good specificity and sensitivity, and could accurately identify single base mutations in mixed targets, with the minimum detection limit as low as 1.0 pmol/L. The recoveries of simulated serum samples were 95.0%-105.2%. In conclusion, the constant temperature amplification multiple detection method constructed in this study can quickly realize the single-tube multiple detection of three drug resistance mutation sites. This technology is low-cost, simple and rapid, and does not rely on large equipment, providing a new analysis method for pathogen drug resistance gene detection.

[Predicting zoonotic diseases dynamics using mathematic models].

The interspecies transmission of pathogens among multiple hosts is a complex dynamic process, which poses a severe challenge to the reliability of the early warning system of zoonotic infectious diseases. By introducing the theories and methods of infectious disease ecology, this paper reviews and summarizes the study of the interaction among pathogens, hosts and environment through the dynamic mathematical model of environment-host-infectious diseases, and also includes research paradigm for quantifying the effects of environment on epidemic trends, vectors and pathogenic microorganisms. Taking the study of Apodemus-type hemorrhagic fever with renal syndrome, also known as epidemic hemorrhagic fever, in China as an example, the application of mathematical model of infectious diseases in actual prediction and early warning of epidemic situation is introduced, and new monitoring indexes and early warning methods is further developed.

Controllable valley filter in graphene topological line defect with magnetic field.

The extended line defect of graphene is an extraordinary candidate in valleytronics while the high valley polarization can only occur for electrons with high incidence angles which brings about tremendous challenges to experimental realization. In this paper, we propose a novel quantum mechanism to filter one conical valley state in the line defect of graphene by applying a local magnetic field. It is found that due to the movement of the Dirac points, the transmission profiles of the two valleys are shifted along the injection-angle axis at the same pace, resulting in the peak transmission of one valley state being reduced drastically while remaining unaffected for the other valley state, which induces nearly perfect valley polarization. The valley polarization effect can occur for all the incident angle and plays a key role in graphene valleytronics.

[2019-nCoV: new challenges from coronavirus].

The outbreak of pneumonia caused by the novel coronavirus (2019-nCoV) in Wuhan, Hubei province of China, at the end of 2019 shaped tremendous challenges to China's public health and clinical treatment. The virus belongs to the ß genus Coronavirus in the family Corornaviridae, and is closely related to SARS-CoV and MERS-CoV, causing severe symptoms of pneumonia. The virus is transmitted through droplets, close contact, and other means, and patients in the incubation period could potentially transmit the virus to other persons. According to current observations, 2019-nCoV is weaker than SARS in pathogenesis, but has stronger transmission competence; it's mechanism of cross-species spread might be related with angiotensin-converting enzyme Ⅱ (ACE2), which is consistent with the receptor SARS-CoV. After the outbreak of this disease, Chinese scientists invested a lot of energy to carry out research by developing rapid diagnostic reagents, identifying the characters of the pathogen, screening out clinical drugs that may inhibit the virus, and are rapidly developing vaccines. The emergence of 2019-nCoV reminds us once again of the importance of establishing a systematic coronavirus surveillance network. It also poses new challenges to prevention and control of the emerging epidemic and rapidly responses on scientific research.

[2019-nCoV: new challenges from coronavirus].

The outbreak of pneumonia caused by the novel coronavirus 2019-nCoV in Wuhan, Hubei province of China, at the end of 2019 shaped tremendous challenges to China's public health and clinical treatment. The virus belongs to the ß genus Coronavirus in the family Corornaviridae, and is closely related to SARS-CoV and MERS-CoV, causing severe symptoms of pneumonia. The virus is transmitted through droplets, close contact, and other means, and patients in the incubation period could potentially transmit the virus to other persons. According to current observations, 2019-nCoV is weaker than SARS in pathogenesis, but has stronger transmission competence; it's mechanism of cross-species spread might be related with angiotensin-converting enzyme Ⅱ (ACE2), which is consistent with the receptor SARS-CoV. After the outbreak of this disease, Chinese scientists invested a lot of energy to carry out research by developing rapid diagnostic reagents, identifying the characters of the pathogen, screening out clinical drugs that may inhibit the virus, and are rapidly developing vaccines. The emergence of 2019-nCoV reminds us once again of the importance of establishing a systematic coronavirus surveillance network. It also poses new challenges to prevention and control of the emerging epidemic and rapidly responses on scientific research.

Adherence to the 2006 American Heart Association's Diet and Lifestyle Recommendations for cardiovascular disease risk reduction is associated with bone mineral density in older Chinese.

This cross-sectional study investigated the association between the modified 2006 American Heart Association Diet and Lifestyle Recommendations (AHA-DLR) and bone mineral density in Chinese adults. We found that better adherence to the AHA-DLR associated with higher bone mineral density (BMD) at multiple sites. INTRODUCTION: Accumulating evidence shows that cardiovascular disease (CVD) and osteoporosis are associated with each other, yet little research has focused on whether strategies to reduce CVD risk could also benefit bone health. We aimed to assess the association between adherence to the modified 2006 American Heart Association Diet and Lifestyle Recommendations (AHA-DLR) and BMD in Chinese adults. METHODS: We included 2092 women and 1051 men aged 40-75 years in this community-based cross-sectional study. Dietary information was assessed using a 79-item food frequency survey through face-to-face interviews at baseline (2008-2010) and 3 years later (2011-2013). Adherence to the AHA-DLR was assessed using modified diet and lifestyle scores (American Heart Association Diet and Lifestyle Score (AHA-DLS)) adjusted for bone health. BMD for the whole body, lumbar spine, total hip, femur neck, and trochanter sites was measured using dual-energy X-ray absorptiometry in 2011-2013. RESULTS: After adjusting for potential covariates, greater adherence to the modified AHA-DLS was positively and dose-dependently associated with BMD. The mean BMD was 1.93-3.11% higher in quartile 4 (vs. 1) (all p values <0.01) at multiple sites. Five-unit increases in the modified AHA-DLS score were associated with 4.20-6.07, 4.44-8.51, and 3.36-4.67 mg/cm2 increases in BMD at multiple sites for the total subjects, males, and females, respectively (all p values <0.01). CONCLUSIONS: Better adherence to the AHA-DLR shows protective associations with BMD at multiple sites in the middle-aged and elderly Chinese population.

[Durability of protective effect of resin-based coating material on root surface].

OBJECTIVE: To compare the durability of resin-based root-surface coating material and all-in-one self-etching adhesive on root surface in vitro. METHODS: Human extracted premolars or molars with intact roots were selected. The cementum was removed using a periodontal scaler to expose root dentin. The root surface was coated with an acid-resistant nail varnish, leaving a window of 3 mm×3 mm on the exposed dentin.The window was covered with either PRG Barrier Coat (PRG) or Clearfil S3 Bond (CS3). After water aging for 14 d, specimens were immersed in acid buffer at pH 4.5 for 4 d and the demineralization buffer was changed every 24 h. Then the specimen was split longitudinally through the center of the 'window' and the cross-sectional surface was observed with scanning electron microscope (SEM). After fixed and dehydrated, the prepared samples were coated with platinum. The coating material, root dentin and the interface was observed by scanning electron microscope (SEM). The thickness of the coating material was measured on the SEM images. Regarding toothbrush wear test, coronal dentindisks were prepared and covered with PRG and CS3, respectively. After storage in water for 24 h, the specimen was subjected to the toothbrush wear tester for 100, 200, 300, 500, 700, 1 500 brushing cycles. A slurry of fluoride toothpaste (1:2 ratio of toothpaste and deionized water by weight) was used and the brushing load was 300 N. The surface microstructure of remaining coating material was analyzed using SEM. The wear depths were determined by a profilometer. Statistical analysis was performed with SPSS 20.0 by one-way ANOVA. The level of significance was at 0.05. RESULTS: Application of PRG Barrier Coat produced a coating layer of (47.1±27.3) µm, while CS3 presented a thin film of (5.7±2.1) µm in thickness. The exposed dentin was hermetically sealed and no obvious gap was observed at the interface in both PRG and CS3 groups. There was no dentin demineralization observed in both groups after water aging. The wear depths of PRG and CS3 increased along with the numbers of brushing cycles. PRG wore at a significant lower pace than CS3 did (P<0.05). CONCLUSION: PRG coating resin had similar performances as CS3 on protecting root dentin from demineralization after water aging. What's more, PRG demonstrated a higher toothbrush wear resistance than CS3. We concluded that PRG Barrier Coat contained S-PRG filler may be an effective coating material for protecting exposed root from both chemical and mechanical challenges. Further studies should be carried out to evaluate the long-term reliability of the rootsurface coating materials under the clinical setting.

An analysis of the intervention effect of perioperative evidence-based nursing on orthopedic trauma patients' vagal reflex.

OBJECTIVE: to discuss the application value of evidence-based nursing (EBN) on orthopedic trauma patients' perioperative vagus reflex intervention effect. PATIENTS AND METHODS: Eighty-six patients were selected, who were hospitalized in orthopedics department of our hospital because of trauma from March, 2013 to March, 2014. Then, they were divided into the control group (n = 41 cases) and the treatment group (n = 45 cases) according to random number table after obtaining the consent of the Hospital Ethics Committee and the informed consent of the patients as well as their relatives. Control group patients were treated with conventional nursing before, during and after operation, and treatment group patients were treated with EBN. Then, the incidence of vagal reflex on the two groups of patients was compared. HRV frequency domain was applied to analyze the differences of autonomic nervous function changes on the two groups of patients, and ELISA test was taken to detect the differences of the concentration change of serum TNF-alpha and IL-6. RESULTS: The prevalence of vagal reflex on patients in treatment group was significantly lower than that in the control group, with statistically significant difference (p < 0.05); low frequency (LF) and high frequency (HF) on patients from both groups decreased after treatment while LF/HF increased, and LF and HF on patients of the treatment group decreased more significantly and LF/HF increased more significantly than those of the control group, with statistically significant difference (p < 0.05); the concentration of TNF-alpha and IL-6 on both groups of patients after nursing also decreased, and the treatment group decreased more significantly, with statistically significant difference (p < 0.05). CONCLUSIONS: EBN could reduce the prevalence of vagal reflex to some extent on perioperative orthopedic trauma patients. It might be because EBN could improve vagal tone and reduce the concentration of TNF-alfa and IL-6.

Hantavirus infection in rodents and haemorrhagic fever with renal syndrome in Shaanxi province, China, 1984-2012.

The transmission of haemorrhagic fever with renal syndrome (HFRS) is deeply influenced by the reservoir and hantavirus prevalence rate. In this study, a surveillance on human HFRS cases, relative rodent abundance, and hantavirus infection prevalence was conducted in Shaanxi province, China, during 1984-2012. A generalized linear model with Poisson-distributed residuals and a log link was used to quantify the relationship between reservoir, virus and HFRS cases. The result indicated that there was a significant association of HFRS incidence with relative rodent density and the prevalence rate. This research provides evidence that the changes of infection prevalence in the reservoir could lead directly to the emergence of a new epidemic. It was concluded that the measurement of a number of these variables could be used in disease surveillance to give useful advance warning of potential disease epidemics.

Disorder effect on the integer quantum Hall effect in trilayer graphene.

We numerically investigate the disorder effect on the integer quantum Hall effect in a trilayer graphene (TLG) system by use of the Kubo formula. For a clean sample, both Bernal (ABA) and rhombohedral (ABC) stacked TLGs display the same quantum rule with abnormal quantized Hall plateaus σxy = νe(2)/h (ν =± 6, ± 10, ± 14,…) in the band center and normal quantized Hall plateaus at the band edges. In the presence of disorder, the Hall plateaus become obscure and the higher plateaus disappear first with the increase of the disorder; however, the Hall plateaus of the ABA-stacked TLG are destroyed more readily in comparison with the ABC-stacked one. The longitudinal conductance minimums of the system corresponding to the Hall plateaus become narrower and thinner with disorder, and those of the ABC-stacked TLG are comparatively more stable than those of the ABA structure. The findings indicate that the l = 3 chiral quasiparticles with cubic energy dispersion in ABC-stacked TLG have comparatively stronger immunity to the disorder than the l = 1 and 2 chiral quasiparticles in the ABA counterpart.

Environmental variability and the transmission of haemorrhagic fever with renal syndrome in Changsha, People's Republic of China.

The transmission of haemorrhagic fever with renal syndrome (HFRS) is influenced by climatic, reservoir and environmental variables. The epidemiology of the disease was studied over a 6-year period in Changsha. Variables relating to climate, environment, rodent host distribution and disease occurrence were collected monthly and analysed using a time-series adjusted Poisson regression model. It was found that the density of the rodent host and multivariate El Niño Southern Oscillation index had the greatest effect on the transmission of HFRS with lags of 2­6 months. However, a number of climatic and environmental factors played important roles in affecting the density and transmission potential of the rodent host population. It was concluded that the measurement of a number of these variables could be used in disease surveillance to give useful advance warning of potential disease epidemics.

KOH catalysed preparation of activated carbon aerogels for dye adsorption.

Organic carbon aerogels (CAs) were prepared by a sol-gel method from polymerisation of resorcinol, furfural, and hexamethylenetetramine catalysed by KOH at around pH 9 using ambient pressure drying. The effect of KOH in the sol-gel on CA synthesis was studied. It was found that addition of KOH prior to the sol-gel polymerisation process improved thermal stability of the gel, prevented the crystallinity of the gel to graphite, increased the microporosity of CA and promoted activation of CA. The CAs prepared using the KOH catalyst exhibited higher porosity than uncatalysed prepared samples. Activation in CO(2) at higher temperature also enhanced the porosity of CAs. Adsorption tests indicated that the CAs were effective for both basic and acid dye adsorption and the adsorption increased with increasing surface area and pore volume. The kinetic adsorption of dyes was diffusion control and could be described by the second-order kinetic model. The equilibrium adsorption of dyes was higher than activated carbon.

A phenomenological approach to the anisotropic magnetoresistance and planar Hall effect in tetragonal La(2/3)Ca(1/3)MnO3 thin films.

A La(2/3)Ca(1/3)MnO(3) Hall bar with its long dimension roughly along the hard axis [110] was fabricated on a single-crystal-like tensilely strained film on SrTiO(3)(001). The anisotropic magnetoresistance (AMR) and planar Hall effect (PHE) have been studied at various external magnetic fields and temperatures. A phenomenological model in the high field limit is developed, and the galvanomagnetic tensor based on a tetragonal symmetry 4/mmm (D(4h)), applicable to epitaxial films on a substrate, has been obtained by expanding the tensor to the sixth order. The derived in-plane transverse resistance R(xy) shows a sin2φ(M) angular dependence, while the longitudinal R(xx) is constituted by not only a two-fold cos2φ(M) term, but also a four-fold cos4φ(M) term due to the square symmetry of the lattice. The model is in good agreement with the experimental results in high fields, while deviations are observed near the {100} easy axis with the decreasing field. Close inspection of the fitting parameters reveals the evolution of these term weights with temperature and magnetic field, which is distinct from conventional ferromagnetic metals and cannot be explained by the phenomenological model. An alternative mechanism for AMR, stemming from the magnetization-induced local orbit deformation through spin-orbit interaction, as previously proposed by O'Donnell et al, may be prevalent in manganites and other systems of complicated crystal structure.

Preparation, microstructure and hydrogen sorption properties of nanoporous carbon aerogels under ambient drying.

Organic aerogels are prepared by the sol-gel method from polymerization of resorcinol with furfural. These aerogels are further carbonized in nitrogen in order to obtain their corresponding carbon aerogels (CA); a sample which was carbonized at 900 °C was also activated in a carbon dioxide atmosphere at 900 °C. The chemical reaction mechanism and optimum synthesis conditions are investigated by means of Fourier transform infrared spectroscopy and thermoanalyses (thermogravimetric/differential thermal analyses) with a focus on the sol-gel process. The carbon aerogels were investigated with respect to their microstructures, using small angle x-ray scattering (SAXS), transmission electron microscopy (TEM) and nitrogen adsorption measurements at 77 K. SAXS studies showed that micropores with a radius of gyration of <0.35 ± 0.07 to 0.55 ± 0.05 nm were present, and TEM measurements and nitrogen adsorption showed that larger mesopores were also present. Hydrogen storage properties of the CA were also investigated. An activated sample with a Brunauer-Emmett-Teller surface area of 1539 ± 20 m(2) g(-1) displayed a reasonably high hydrogen uptake at 77 K with a maximum hydrogen sorption of 3.6 wt% at 2.5 MPa. These results suggest that CA are promising candidate hydrogen storage materials.