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Epilepsy ranks fourth among neurological diseases, featuring spontaneous seizures and behavioural and cognitive impairments. Although anti-epileptic drugs are currently available clinically, 30 % of epilepsy patients are still ineffective in treatment and 52 % of patients experience serious adverse reactions. In this work, the neuroprotective effect of α-linolenic acid (ALA, a nutrient) in mice and its potential molecular mechanisms exposed to pentylenetetrazol (PTZ) was assessed. The mice were injected with pentetrazol 37 mg/kg, and ALA was intra-gastrically administered for 40 d. The treatment with ALA significantly reduced the overall frequency of epileptic seizures and improved the behaviour impairment and cognitive disorder caused by pentetrazol toxicity. In addition, ALA can not only reduce the apoptosis rate of brain neurons in epileptic mice but also significantly reduce the content of brain inflammatory factors (IL-6, IL-1 and TNF-α). Furthermore, we predicted that the possible targets of ALA in the treatment of epilepsy were JAK2 and STAT3 through molecular docking. Finally, through molecular docking and western blot studies, we revealed that the potential mechanism of ALA ameliorates PTZ-induced neuron apoptosis and neurological impairment in mice with seizures by down-regulating the JAK2/STAT3 pathway. This study aimed to investigate the anti-epileptic and neuroprotective effects of ALA, as well as explore its potential mechanisms, through the construction of a chronic ignition mouse model via intraperitoneal PTZ injection. The findings of this research provide crucial scientific support for subsequent clinical application studies in this field.
Let $[a_1(x),a_2(x),a_3(x),\ldots ]$ be the continued fraction expansion of an irrational number $x\in [0,1)$. We are concerned with the asymptotic behaviour of the product of consecutive partial quotients of x. We prove that, for Lebesgue almost all $x\in [0,1)$,
We also study the Baire category and the Hausdorff dimension of the set of points for which the above liminf and limsup have other different values and similarly analyse the weighted product of consecutive partial quotients.
The super-temporal-resolution (STR) reconstruction of turbulent flows is an important data augmentation application for increasing the data reach in measurement techniques and understanding turbulence dynamics. This paper proposes a data assimilation (DA) strategy based on weak-constraint four-dimensional variation to conduct an STR reconstruction in a turbulent jet beyond the Nyquist limit from given low-sampling-rate observations. Highly resolved large-eddy simulation (LES) data are used to produce synthetic measurements, which are used as observations and for validation. A segregated assimilation procedure is realised to assimilate the initial condition, inflow boundary condition and model error separately. Different types of observational data are tested. The first type is down-sampled LES data containing many small-scale turbulence structures with or without synthetic noise. The DA results show that the temporal variation of the small-scale structures is well recovered even with noise in the observations. The spectra are resolved to a frequency approximately one order of magnitude higher than what can be captured within the Nyquist limit. The second type of observation is low-sampling-rate tomographic particle image velocimetry (tomo-PIV) data with or without the injection of small-scale structures. The modulation between the large-scale structures contained in the tomo-PIV fields and the small scales injected from the observations is improved. The resultant small scales in the STR reconstruction have the characteristics of authentic turbulence to a considerable extent. Additionally, DA yields much smaller errors in the prediction of particle positions when compared with the Wiener filter, demonstrating the great potential for Lagrangian particle tracking in measurement techniques.
Adsorption of nanoparticles on minerals affects the fate and transport of nanoparticles directly and is of great significance to many fields, including research into ore deposits, geochemistry, the environment and mineral materials. Whereas many previous studies have been conducted under the equilibrium pH and low solid (mineral) to liquid (nanoparticle suspension) ratio conditions, adsorption processes under initial pH and high solid/liquid ratio conditions may represent many important yet underexamined complex scenarios. To fill in this research gap, the adsorption of gold nanoparticles on illite was investigated experimentally at a relatively high solid/liquid ratio of 5 g L–1 and the effects of initial pH, ionic strength, citrate concentration, temperature and illite particle size were evaluated. The adsorbed amount of gold nanoparticles (from <5% to nearly 100%) increased with increasing ionic strength, temperature and citrate concentration and decreased with increasing pH and illite particle size. The presence of illite resulted in the dynamic evolution of the pH of the suspension, which, along with solution chemistry parameters, controlled the electrostatic interaction of illite and gold nanoparticles. The adsorption results, scanning electron microscopy observations and surface properties of illite suggest that the negatively charged gold nanoparticles were adsorbed predominantly on the positive illite edges through electrostatic interaction. The electrostatic attraction between illite and gold nanoparticles appeared to be strong, supported by the minor amount of desorption. These research findings are expected to provide a valuable reference regarding many critical issues in the geosciences as well as for industrial applications.
Breast cancer is a high-risk disease with a high mortality rate among women. Chemotherapy plays an important role in the treatment of breast cancer. However, chemotherapy eventually results in tumours that are resistant to drugs. In recent years, many studies have revealed that the activation of Wnt/β-catenin signalling is crucial for the emergence and growth of breast tumours as well as the development of drug resistance. Additionally, drugs that target this pathway can reverse drug resistance in breast cancer therapy. Traditional Chinese medicine has the properties of multi-target and tenderness. Therefore, integrating traditional Chinese medicine and modern medicine into chemotherapy provides a new strategy for reversing the drug resistance of breast tumours. This paper mainly reviews the possible mechanism of Wnt/β-catenin in promoting the process of breast tumour drug resistance, and the progress of alkaloids extracted from traditional Chinese medicine in the targeting of this pathway in order to reverse the drug resistance of breast cancer.
The phase summation effect in sum-frequency mixing process is utilized to avoid a nonlinearity obstacle in the power scaling of single-frequency visible or ultraviolet lasers. Two single-frequency fundamental lasers are spectrally broadened by phase modulation to suppress stimulated Brillouin scattering in fiber amplifier and achieve higher power. After sum-frequency mixing in a nonlinear optical crystal, the upconverted laser returns to single frequency due to phase summation, when the phase modulations on two fundamental lasers have a similar amplitude but opposite sign. The method was experimentally proved in a Raman fiber amplifier-based laser system, which generated a power-scalable sideband-free single-frequency 590 nm laser. The proposal manifests the importance of phase operation in wave-mixing processes for precision laser technology.
High-power continuous-wave single-frequency Er-doped fiber amplifiers at 1560 nm by in-band and core pumping of a 1480 nm Raman fiber laser are investigated in detail. Both co- and counter-pumping configurations are studied experimentally. Up to 59.1 W output and 90% efficiency were obtained in the fundamental mode and linear polarization in the co-pumped case, while less power and efficiency were achieved in the counter-pumped setup for additional loss. The amplifier performs indistinguishably in terms of laser linewidth and relative intensity noise in the frequency range up to 10 MHz for both configurations. However, the spectral pedestal is raised in co-pumping, caused by cross-phase modulation between the pump and signal laser, which is observed and analyzed for the first time. Nevertheless, the spectral pedestal is 34.9 dB below the peak, which has a negligible effect for most applications.
Lower-crust-derived adakitic rocks in the Gangdese belt provide important constraints on the timing of Tibetan crustal thickening and on the relative contributions of magmatic and tectonic processes. Here we present geochronological and geochemical data for the Wangdui porphyritic monzogranites in the western Gangdese belt. Zircon U–Pb dating yields emplacement ages of 46–44 Ma. All samples have high Sr (321–599 ppm), low Yb (0.76–1.33 ppm) and Y (10.6–18.3 ppm) contents, with high La/Yb (51.1–72.3) and Sr/Y (21.0–51.4) ratios, indicating adakitic affinities. The low MgO (0.97–1.76 wt %), Cr (7.49–53.6 ppm) and Ni (4.75–29.1 ppm) contents, as well as high 87Sr/86Sr(i) (0.7143–0.7145), low ϵNd(t) (−10.4 to −9.8) and zircon ϵHf(t) (−17.7 to 0.4) values, suggest that the Wangdui pluton most likely originated from partial melting of the thickened ancient lower crust. In combination with previously published data, despite the east–west-trending heterogeneity of crustal composition in the Gangdese belt, the La/Yb ratios of magmatic rocks reveal that both western and eastern segments experienced remarkable crustal thickening in the Eocene. However, in contrast to the thickened juvenile lower crust in the eastern segment formed by the underplating of mantle-derived magmas, tectonic shortening plays a more crucial role in thickening of the ancient basement in western Gangdese. In fact, such Eocene-thickened ancient lower-crust-derived adakitic rocks are widely distributed in the central Himalayan–Tibetan orogen. This, together with the extensive development of fold–thrust belts, suggests that tectonic shortening might be the main mechanism accounting for the crustal thickening associated with the India–Asia collision.
Cognitive decline in advanced age is closely related to dementia. The trajectory of cognitive function in older Chinese is yet to be fully investigated. We aimed to investigate the trajectories of cognitive function in a nationally representative sample of older people living in China and to explore the potential determinants of these trajectories.
Methods:
This study included 2,038 cognitively healthy persons aged 65–104 years at their first observation in the Chinese Longitudinal Healthy Longevity Survey from 2002 to 2014. Cognitive function was measured using the Chinese version of the Mini-Mental State Examination (MMSE). Group-based trajectory modeling was used to identify potential heterogeneity of longitudinal changes over the 12 years and to investigate associations between baseline predictors of group membership and these trajectories.
Results:
Three trajectories were identified according to the following types of changes in MMSE scores: slow decline (14.0%), rapid decline (4.5%), and stable function (81.5%). Older age, female gender, having no schooling, a low frequency of leisure activity, and a low baseline MMSE score were associated with the slow decline trajectory. Older age, body mass index (BMI) less than 18.5 kg/m2, and having more than one cardiovascular disease (CVD) were associated with the rapid decline trajectory.
Conclusion:
Three trajectories of cognitive function were identified in the older Chinese population. The identified determinants of these trajectories could be targeted for developing prevention and intervention strategies for dementia.
To evaluate the effects of gestational weight gain (GWG) in the first trimester (GWG-F) and the rate of gestational weight gain in the second trimester (RGWG-S) on gestational diabetes mellitus (GDM), exploring the optimal GWG ranges for the avoidance of GDM in Chinese women.
Design:
A population-based prospective study was conducted. Gestational weight was measured regularly in every antenatal visit and assessed by the Institute of Medicine (IOM) criteria (2009). GDM was assessed with the 75-g, 2-h oral glucose tolerance test at 24–28 weeks of gestation. Multivariable logistic regression was performed to assess the effects of GWG-F and RGWG-S on GDM, stratified by pre-pregnancy BMI. In each BMI category, the GWG values corresponding to the lowest prevalence of GDM were defined as the optimal GWG range.
Setting:
Southwest China.
Participants:
Pregnant women (n 1910) in 2017.
Results:
After adjusting for confounders, GWG-F above IOM recommendations increased the risk of GDM (OR; 95 % CI) among underweight (2·500; 1·106, 5·655), normal-weight (1·396; 1·023, 1·906) and overweight/obese women (3·017; 1·118, 8·138) compared with women within IOM recommendations. No significant difference was observed between RGWG-S and GDM (P > 0·05) after adjusting for GWG-F based on the previous model. The optimal GWG-F ranges for the avoidance of GDM were 0·8–1·2, 0·8–1·2 and 0·35–0·70 kg for underweight, normal-weight and overweight/obese women, respectively.
Conclusions:
Excessive GWG in the first trimester, rather than the second trimester, is associated with increased risk of GDM regardless of pre-pregnancy BMI. Obstetricians should provide more pre-emptive guidance in achieving adequate GWG-F.
X-ray powder diffraction data, unit-cell parameters and space group for azilsartan, C25H20N4O5, are reported [a = 9.641(3) Å, b = 11.301(9) Å, c = 20.010(8) Å, α = 90°, β = 90.351(5)°, γ = 90°, unit-cell volume V = 2196.735(4) Å3, Z = 4, ρcal = 1.379 g·cm−3, and space group P21/c]. All measured lines were indexed and are consistent with the P21/c space group. No detectable impurities were observed.
X-ray powder diffraction data, unit-cell parameters, and space group for alogliptin benzoate, C18H21N5O2·C7H6O2, are reported [a = 28.8260(8) Å, b = 9.9654(4) Å, c = 8.1477(8) Å, α = 90, β = 90, γ = 90°, unit-cell volume V = 2340.57 Å3, Z = 4, ρcal = 1.3097 g cm−3, and space group P212121]. All measured lines were indexed and are consistent with the P212121 space group, No detectable impurities were observed.
On April 25, 2015, a massive 8.1-magnitude earthquake struck Nepal at 2:11 pm (Beijing time). The 68-member-strong China International Search & Rescue Team (CISAR) left for Nepal at 6 am, April 26, to help with relief work. The CISAR was the first foreign team to rescue a survivor who was trapped beneath the rubble in the Gongabu area after the earthquake. On May 8, the team fulfilled the search-and-rescue mission and returned to Beijing. During the 2 weeks of rescue work, the team treated more than 3700 victims and cleared approximately 430 buildings. In this rescue mission, 10 experienced medical officers (including nine doctors and a nurse) from the General Hospital of Chinese People’s Armed Police Force (PAP) comprised the medical team of CISAR. In this report, we focus on the medical rescues by CISAR and discuss the characteristics of the medical rescue in Nepal. (Disaster Med Public Health Preparedness. 2018;12:536–538)
The present study was performed to test the predictive value of different cut-off points of anthropometric parameters for the presence of type 2 diabetes (T2DM) or glucose tolerance abnormalities in north-east Chinese adults.
Design
Multistage random cluster sampling method in a cross-sectional study.
Setting
Height, body weight, maximal body weight in the past, waist and hip circumferences, blood pressure, 2 h post-load glucose and other lifestyle factors were measured.
Subjects
We used data from 1058 adults aged 20 years or over, selected in the city of Mudanjiang, in 2005.
Results
BMI, maximal BMI in the past (MAXBMI), waist:hip ratio (WHR), waist:height ratio (WHtR) and waist circumference (WC) were significantly correlated with each other. Partial correlation coefficients between WHtR and WC, and between MAXBMI and BMI, were higher than those between the other indices. The association of anthropometric indices with T2DM or glucose tolerance abnormalities was significantly highest for the collaboration cut-off points of MAXBMI (≥23·0 kg/m2 for T2DM, ≥22·0 kg/m2 for glucose tolerance abnormalities) with WHtR (≥0·52). Areas under the receiver-operating characteristic curves also showed that WHtR was a better anthropometric index that discriminated between the presence and absence of T2DM and an excellent indicator with high Youden’s index.
Conclusions
MAXBMI combined with WHtR was a better anthropometric index associated with T2DM or glucose tolerance abnormalities. The combined use of these two measures is a good choice for T2DM prevention and screening.
The hot water tail-flick test is widely used to measure the degree of nociception experienced by laboratory animals. This study was carried out to optimise interval times for the hot water immersion tail-flick tests in rats.
Method
Ten different intervals from 10 s to 1 h were tested in 60 Sprague–Dawley male rats. At least eight rats were tested for each interval in three consecutive hot water tail-flick tests. Dixon's up-and-down method was also used to find the optimal intervals. The same rats were then divided into two groups. In Group N, naloxone was injected to reverse the prolonged latency times, whereas saline was used in the control Group S.
Results
Intervals of 10 s, 20 s, 30 min and 1 h did not significantly impact latencies, yielding similar results in three consecutive tests (p > 0.05). However, interval times of between 30 s and 20 min, inclusively, caused significantly prolonged latencies in the second and third tests (p < 0.001). Dixon's up-and-down method showed that 95% of the rats had prolonged latencies in hot water tail-flick tests at intervals longer than 32 s. Naloxone reversed prolonged latencies in Group N, whereas the latencies in Group S were further prolonged in 5 min interval tests.
Conclusion
The optimal intervals for hot water tail-flick tests are either shorter than 20 s or longer than 20 min. The prolonged latencies after repetitive tests were attributable to an endocrine opioid.
An experiment on Al-Cu impedance-match targets, carried out at the Shenguang highpower laser facility, is described. The shock adiabat of Cu in the pressure region 0.4- 0.8 TPa, measured experimentally, is close to the extrapolated results of the data at lower pressure obtained with a high-explosive loading facility and also is in agreement with the data at high pressure measured in the underground nuclear test environment.
Primordial germ cells (PGCs) were isolated from the genital ridges of chicken (Gallus domesticus) embryos at the 19th stage and purified by Ficoll density-gradient centrifugation. PGCs were co-cultured with somatic cells in preliminary culture and subcultured. Identification of PGCs was carried out by histochemical methods, including alkaline phosphatase (AKP) and periodic acid–Schiff (PAS). The proliferating activity of PGCs in subculture was demonstrated by immunocytochemistry of proliferating cell nuclear antigen (PCNA). Meanwhile, proliferating PGCs were compared under different culture conditions of 5–20% fetal cattle serum (FCS), insulin–transferrin–selenite (ITS) medium, conditioned medium (CM), 15% FCS+ITS, 15% FCS+40% CM. The results showed that the cultured PGCs were positive for AKP and PAS staining and displayed intensive proliferating activity by PCNA. The PGCs without centrifugation grew better than those with centrifugation. The PGCs formed larger colonies in media with 5% FCS or ITS than other media, indicating that 5% FCS or ITS supplemented media could be an ideal culture system for PGC proliferation in the PGC-somatic cell co-culture, in addition to the embryonic fibroblast feeder layer.
In order to allow people to explore potential fire environments without risk of danger, a new fire scout mobile robot used in urban environments is introduced in this paper. It adapts itself to stair climbing by using articulated-chain-wheeled mobile style with differential wheels. The positive pressure with continuous flow of protected gas inside the body endows the robot with explosion protection capability. When the wireless control signal is interrupted, it could automatically return to safe place along previous path based on sensorial data. Since position estimation only using encoders reading has serious limitations as mobile robot movement proceeds, a novel method integrating data of encoders and ultrasonic sensors is built, which uses iterative closest point algorithm to do data matching so as to adjust position and orientation of the mobile robot. This path retracing method realizes high accuracy and fast speed of automatic returning when the mobile robot is working in static urban environment even if the environment is unknown.