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An ultra-wideband (UWB) and compact-size four-port multiple input multiple output (MIMO) antenna with a footprint of 34 mm × 34 mm fed by an asymmetric coplanar strip (ACS) is investigated. The proposed antenna is composed of four orthogonally placed identical modified elliptical-shaped radiators and achieves an impedance bandwidth of 3.4–12.2 GHz. By etching two inverted L-shaped slots in the radiator element, WLAN band and X-band are rejected in the operating communication range. Because of the usage of a meander line decoupler, the isolation enhancement at the 8–12 GHz band is achieved and the isolation is more than 18 dB for most of the UWB range. The performance of the proposed antenna is studied in terms of isolation between each port, radiation pattern, current distribution, gain, envelope correlation coefficient, diversity gain, and total active reflection coefficient. The compact size and reduced complexity make the proposed design highly suitable for portable devices.
To improve contact tracing for healthcare workers, we built and configured a Bluetooth low-energy system. We predicted close contacts with great accuracy and provided an additional contact yield of 14.8%. This system would decrease the effective reproduction number by 56% and would unnecessarily quarantine 0.74% of employees weekly.
An online pattern recognition method of lower limb movements is proposed based on the personalized surface electromyography (sEMG) signals, and the corresponding experimental researches are performed in the rehabilitation training. Further, a wireless wearable acquisition instrument is used. Based on this instrument, a host computer for the personal online recognition and real-time control of rehabilitation training is developed. Three time-domain features and two features in the nonlinear dynamics are selected as the joint set of the characteristic values for the sEMG signals. Then a particle swarm optimization (PSO) algorithm is used to optimize the feature channels, and a k-nearest neighbor (KNN) algorithm and the extreme learning machine (ELM) algorithm are combined to classify and recognize individual sample data. Based on the multi-pose lower limb rehabilitation robot, the real-time motion recognition and the corresponding rehabilitation training are carried out by using the online personalized classifier. The experimental results of eight subjects indicate that it takes only 6 min to build an online personalized classifier for the four types of the lower limb movements. The recognition between switches of different rehabilitation training movements is timely and accurate, with an average recognition accuracy of more than 95%. These results demonstrate that this system has a strong practicability.
The burden of mental disorders is increasing worldwide, thus, affecting society and healthcare systems. This study investigated the independent influences of age, period and cohort on the global prevalence of mental disorders from 1990 to 2019; compared them by sex; and predicted the future burden of mental disorders in the next 25 years.
The age-specific and sex-specific incidence of mental disorders worldwide was analysed according to the general analysis strategy used in the Global Burden of Disease Study in 2019. The incidence and mortality trends of mental disorders from 1990 to 2019 were evaluated through joinpoint regression analysis. The influences of age, period and cohort on the incidence of mental disorders were evaluated with an age–period–cohort model.
From 1990 to 2019, the sex-specific age-standardized incidence and disability-adjusted life years (DALY) rate decreased slightly. Joinpoint regression analysis from 1990 to 2019 indicated four turning points in the male DALY rate and five turning points in the female DALY rate. In analysis of age effects, the relative risk (RR) of incidence and the DALY rate in mental disorders in men and women generally showed an inverted U-shaped pattern with increasing age. In analysis of period effects, the incidence of mental disorders increased gradually over time, and showed a sub-peak in 2004 (RR, 1.006 for males; 95% CI, 1.000–1.012; 1.002 for women, 0.997–1.008). Analysis of cohort effects showed that the incidence and DALY rate decreased in successive birth cohorts. The incidence of mental disorders is expected to decline slightly over the next 25 years, but the number of cases is expected to increase.
Although the age-standardized burden of mental disorders has declined in the past 30 years, the number of new cases and deaths of mental disorders worldwide has increased, and will continue to increase in the near future. Therefore, relevant policies should be used to promote the prevention and management of known risk factors and strengthen the understanding of risk profiles and incidence modes of mental disorders, to help guide future research on control and prevention strategies.
Dietary antioxidant indices (DAI) may be potentially associated with relative telomere length (RTL) of leucocytes. This study aimed to investigate the relationship between DAI and RTL. A cross-sectional study involving 1656 participants was conducted. A generalised linear regression model and a restricted cubic spline model were used to assess the correlation of DAI and its components with RTL. Generalised linear regression analysis revealed that DAI (β = 0·005, P = 0·002) and the intake of its constituents vitamin C (β = 0·043, P = 0·027), vitamin E (β = 0·088, P < 0·001), Se (β = 0·075, P = 0·003), and Zn (β = 0·075, P = 0·023) were significantly and positively correlated with RTL. Sex-stratified analysis showed that DAI (β = 0·006, P = 0·005) and its constituents vitamin E (β = 0·083, P = 0·012), Se (β = 0·093, P = 0·006), and Zn (β = 0·092, P = 0·034) were significantly and positively correlated with RTL among females. Meanwhile, among males, only vitamin E intake (β = 0·089, P = 0·013) was significantly and positively associated with RTL. Restricted cubic spline analysis revealed linear positive associations between DAI and its constituents’ (vitamin E, Se and Zn) intake and RTL in the total population. Sex-stratified analysis revealed a linear positive correlation between DAI and its constituents’ (vitamin E, Se and Zn) intake and RTL in females. Our study found a significant positive correlation between DAI and RTL, with sex differences.
Currently, students with relatively weak vocal learning foundations generally suffer from learning anxiety disorders. Anxiety disorder is a psychological feeling of excessive worry, and college students’ learning anxiety often leads to uncontrollable worries such as nervousness, panic, and feeling threatened. This learning anxiety will make students increasingly reject learning, thereby affecting learning efficiency.
Subjects and Methods
The study explored three perspectives: establishing a friendly and interactive teacher-student relationship, optimizing the model of vocal music teaching courses in universities, and carrying out innovative course practices. The effectiveness of innovative practice in vocal music teaching courses in universities was tested and verified using the Sarason Exam Anxiety Scale. The experiment used 120 college students from two classes to be divided into a control group and an intervention group. The intervention group learned according to the innovative practice of vocal music teaching courses in universities, while the control group still learned according to the original learning model.
The experimental results show that there is a significant difference in anxiety results between the control group and the intervention group before and after the course implementation. The learning anxiety of students in the control group and intervention group before the innovation practice course experiment was 40.5% and 40.4%, respectively. After innovative practice, the learning anxiety of the two groups of students was 40.8% and 31.5%, respectively.
The innovative practice of vocal music teaching courses in universities can effectively alleviate the learning anxiety of college students.
Many studies have investigated the positivity rate of hepatitis B surface antibody (HBsAb) after hepatitis B vaccine (HepB) immunization. However, the antibody level, assessed monthly or at more frequent intervals after each of the three doses, particularly within the first year after birth, has not been previously reported. To elucidate the level of antibody formation at various times after vaccination, the current study used the available detection data of HBsAb in hospitalized children to analyze the HBsAb level after immunization combined with their vaccination history. Both the positivity rate and geometric mean concentration (GMC) increased sequentially with immunization doses, reaching their peaks earlier after the third dose than after the first two doses, and the rate of HBsAb positivity was able to reach 100% between 11 and 90 days after completing the three doses of HepB. Within one year after receiving the three doses, the antibody positivity rate and GMC were maintained above 90% and 100 mIU/mL, respectively, and subsequently steadily declined, reaching the lowest value in the 9th and 10th years. The current findings reveal, in more detail, the level of antibody formation at different times following each dose of HepB in hospitalized children, particularly in the age group up to one year after vaccination. For the subjects of this study, we prefer to believe that the proportion of HBsAb non-response should be less than 5% after full immunization with HepB, provided that the appropriate time for blood collection is chosen.
Collaboration between local governments and businesses for poverty reduction has not yet been fully explored in China. Based on an in-depth investigation of two counties during the Targeted Poverty Alleviation campaign, this study proposes a multilayered and relational approach to understanding how different levels of officials collaborate with business to reduce poverty. Elite bureaucrats at the county and township levels prefer a growth-oriented strategy for attracting large-scale enterprises to make investment. Their coalition with businesses has created profits and employment but also hindered authentic participation of small- and medium-sized businesses and villagers in their selected villages. In contrast, in villages that were not prioritized by elite bureaucrats, local officials could utilize their discretion and indigenous resources to exploit development opportunities and support small- and medium-sized businesses to reach poor villagers. This study unpacks China's multilevel system to understand the various forms of government–business collaboration and their implications for rural poverty reduction.
The penultimate deglaciation was characterized by a sub-millennial-scale warm event in the Heinrich Stadial 11(HS11), termed the 134-ka event. However, its precise timing and structure remain poorly constrained due to the lack of high-resolution and precisely dated records. We present an oxygen isotope record of a speleothem with well-developed annual lamina from Zhangjia Cave, located on the north margin of the Sichuan Basin, characterizing Asian summer monsoon (ASM) changes in the 134-ka event, which included an increase excursion of ca. 149 years and decrease excursion of ca. 200 years, inferred from 3.3‰ δ18O variations. This event also divided the weak ASM interval-II (WMI-II), corresponding to HS11, into two stages, the WMI-IIa 132.8–134.1 ka and WMI-IIb 134.4–136.4 ka. With a comparable climatic pattern globally, the 134-ka event is essentially similar to the millennial-scale events in last glacial–deglacial period. Particularly, the observed weak-strong-weak ASM sequence (138.8–132.8 ka) is largely controlled by changes in the Atlantic Meridional Overturning Circulation (AMOC) forced by the meltwater of northern high-latitude ice sheets. Moreover, our results underpin that AMOC, rather than the global ice volume, is more critical to ASM variations during the last two deglaciations.
With advancements in cancer treatments, the survival rates of patients with their first primary cancer (FPC) have increased, resulting in a rise in the number of patients with second primary cancer (SPC). However, there has been no assessment on the incidence of suicide among patients with SPC. This study assessed the occurrence of suicide among patients with SPC and compared them with that in patients with FPC.
This was a retrospective, population-based cohort study that followed patients with FPC and SPC diagnosed from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) 17 registries database between 1 January 2000 and 31 December 2019.
For patients with SPC, an age of 85+ years at diagnosis was associated with a higher incidence of suicide death (HR, 1.727; 95% CI, 1.075–2.774), while the suicide death was not considerably different in the chemotherapy group (P > 0.05). Female genital system cancers (HR, 3.042; 95% CI, 1.819–6.361) accounted for the highest suicide death among patients with SPC. The suicide death distribution of patients with SPC over time indicated that suicide events mainly occurred within 5 to 15 years of diagnosis. Compared with patients with FPC, patients with SPC in general had a lower risk of suicide, but increased year by year.
The risk of suicide was reduced in patients with SPC compared with patients with FPC, but increased year by year. Therefore, oncologists and related health professionals need to provide continuous psychological support to reduce the incidence of suicide. The highest suicide death was found among patients with female genital system cancer.
This work demonstrates the generation of short pulse duration and high-beam-quality laser pulses using transient stimulated Brillouin scattering at a high repetition rate. Thermal effects and optical breakdown are identified as the main factors that restrict energy reflectivity and beam quality under high repetition rates and transient situations. Through experimental analysis, the interaction length and focal point size are determined to be the key parameters in reducing the thermal effect by reducing the absorption of the laser pulse by the medium. The obtained results show that pulses with a duration of 175 ps and beam quality M2 of around 1.2 can be achieved with a maximum energy reflectivity of over 40% under an interaction length of 50 mm. Furthermore, at an interaction length of 90 mm, a pulse output with a minimum duration of 115 ps (0.5τQ) is achieved.
Instability evolutions of shock-accelerated thin cylindrical SF$_6$ layers surrounded by air with initial perturbations imposed only at the outer interface (i.e. the ‘Outer’ case) or at the inner interface (i.e. the ‘Inner’ case) are numerically and theoretically investigated. It is found that the instability evolution of a thin cylindrical heavy fluid layer not only involves the effects of Richtmyer–Meshkov instability, Rayleigh–Taylor stability/instability and compressibility coupled with the Bell–Plesset effect, which determine the instability evolution of the single cylindrical interface, but also strongly depends on the waves reverberated inside the layer, thin-shell correction and interface coupling effect. Specifically, the rarefaction wave inside the thin fluid layer accelerates the outer interface inward and induces the decompression effect for both the Outer and Inner cases, and the compression wave inside the fluid layer accelerates the inner interface inward and causes the decompression effect for the Outer case and compression effect for the Inner case. It is noted that the compressible Bell model excluding the compression/decompression effect of waves, thin-shell correction and interface coupling effect deviates significantly from the perturbation growth. To this end, an improved compressible Bell model is proposed, including three new terms to quantify the compression/decompression effect of waves, thin-shell correction and interface coupling effect, respectively. This improved model is verified by numerical results and successfully characterizes various effects that contribute to the perturbation growth of a shock-accelerated thin heavy fluid layer.
A model-free adaptive robust control based on time delay estimation (TDE) is proposed for robot in the presence of disturbance and input saturation. TDE is utilized to estimate the complicated nonlinear terms of the robot including unknown dynamics and disturbance, and a TDE error observer is developed to estimate the inevitable TDE error. When the input torque of the robot exceeds the upper or lower limit of the input saturation, an auxiliary system and a saturation deviation boundary adaptive law are employed to mitigate the negative impact of input saturation on the position tracking. Finally, the robust control law is obtained by backstepping. The stability of the closed-loop system is proved by Lyapunov functions, and the validity of the proposed method is demonstrated by comparative simulations and experiments. Compared with the model-based controllers and other model-free controllers, the proposed method does not necessitate the accurate dynamic model of the complicated system and with lower computation. Moreover, it can guarantee the desired position tracking performance of the robot even subject to disturbance and input saturation simultaneously.
Decreasing symptom-to-door (S2D) delay is of vital importance for reducing morbidity and mortality in patients with ST-segment elevation myocardial infarction (STEMI). The factors associated with S2D delay in STEMI patients have not been well-characterized.
The aim of this study was to identify factors associated with S2D delay in patients with STEMI.
The PubMed, CINAHL, and Embase databases were searched for data. References from the selected articles and relevant background papers were also manually searched to identify additional eligible studies. The included articles were reviewed and assessed for risk of bias. The level of evidence for each identified factor was evaluated using a semiquantitative synthesis.
Twelve (12) papers were included in the review. Factors associated with S2D delay were complex and could be divided into sociodemographic, clinical history, and onset characteristics. The level of evidence regarding female sex and diabetes was strong, and the evidence was moderate regarding older age, smoking, history of hypertension, self-transport, or referral.
Female sex, older age, previous diabetes, previous hypertension, smoking, and self-transport are all strong or moderate risk factors for S2D time delay in patients with ST-segment myocardial infarction. More efforts should be made to educate at-risk populations concerning symptoms of STEMI and the importance of seeking early medical assistance.
To evaluate the potential superiority of donanemab vs. aducanumab on the percentage of participants with amyloid plaque clearance (≤24.1 Centiloids [CL]) at 6 months in patients with early symptomatic Alzheimer's disease (AD) in phase 3 TRAILBLAZER-ALZ-4 study. The amyloid cascade in AD involves the production and deposition of amyloid beta (Aβ) as an early and necessary event in the pathogenesis of AD.
Participants (n = 148) were randomized 1:1 to receive donanemab (700 mg IV Q4W [first 3 doses], then 1400 mg IV Q4W [subsequent doses]) or aducanumab (per USPI: 1 mg/kg IV Q4W [first 2 doses], 3 mg/kg IV Q4W [next 2 doses], 6 mg/kg IV Q4W [next 2 doses] and 10 mg/kg IV Q4W [subsequent doses]).
Baseline demographics and characteristics were well-balanced across treatment arms (donanemab [N = 71], aducanumab [N = 69]). Twenty-seven donanemab-treated and 28 aducanumab-treated participants defined as having intermediate tau.
Upon assessment of florbetapir F18 PET scans (6 months), 37.9% donanemab-treated vs. 1.6% aducanumab-treated participants achieved amyloid clearance (p < 0.001). In the intermediate tau subpopulation, 38.5% donanemab-treated vs. 3.8% aducanumab-treated participants achieved amyloid clearance (p = 0.008).
Percent change in brain amyloid levels were −65.2%±3.9% (baseline: 98.29 ± 27.83 CL) and −17.0%±4.0% (baseline: 102.40 ± 35.49 CL) in donanemab and aducanumab arms, respectively (p < 0.001). In the intermediate tau subpopulation, percent change in brain amyloid levels were −63.9%±7.4% (baseline: 104.97 ± 25.68 CL) and −25.4%±7.8% (baseline: 102.23 ± 28.13 CL) in donanemab and aducanumab arms, respectively (p ≤ 0.001).
62.0% of donanemab-treated and 66.7% of aducanumab-treated participants reported an adverse event (AE), there were no serious AEs due to ARIA in donanemab arm and 1.4% serious AEs (one event) due to ARIA were reported in aducanumab arm.
This study provides the first active comparator data on amyloid plaque clearance in patients with early symptomatic AD. Significantly higher number of participants reached amyloid clearance and amyloid plaque reductions with donanemab vs. aducanumab at 6 months.
Previously presented at the Clinical Trials on Alzheimer's Disease - 15th Conference, 2022.
Four species of Porpidia are newly reported from China, including one species new to science (Porpidia crystallina) and three records (Porpidia umbonifera, P. seakensis and P. cf. contraponenda) new to China. Porpidia crystallina is characterized by a macrocarpa-type exciple containing crystals, a Cinereorufa-green epihymenium, large ascospores and a lack of secondary metabolites. Morpho-anatomical, chemical and phylogenetic analyses were carried out to elucidate the placement of the species and to support the delimitation of the new taxon. Detailed taxonomic descriptions, ecological and chemical characters, and illustrations are provided for each species. A key to all known Chinese Porpidia species is also provided.
This study analyzes the linewidth narrowing characteristics of free-space-running Brillouin lasers and investigates the approaches to achieve linewidth compression and power enhancement simultaneously. The results show that the Stokes linewidth behavior in a free-space-running Brillouin laser cavity is determined by the phase diffusion of the pump and the technical noise of the system. Experimentally, a Stokes light output with a power of 22.5 W and a linewidth of 3.2 kHz was obtained at a coupling mirror reflectivity of 96%, which is nearly 2.5 times compressed compared with the linewidth of the pump (7.36 kHz). In addition, the theorical analysis shows that at a pump power of 60 W and a coupling mirror reflectivity of 96%, a Stokes output with a linewidth of 1.6 kHz and up to 80% optical conversion efficiency can be achieved by reducing the insertion loss of the intracavity. This study provides a promising technical route to achieve high-power ultra-narrow linewidth special wavelength laser radiations.
High-power femtosecond mid-infrared (MIR) lasers are of vast importance to both fundamental research and applications. We report a high-power femtosecond master oscillator power amplifier laser system consisting of a single-mode Er:ZBLAN fiber mode-locked oscillator and pre-amplifier followed by a large-mode-area Er:ZBLAN fiber main amplifier. The main amplifier is actively cooled and bidirectionally pumped at 976 nm, generating a slope efficiency of 26.9%. Pulses of 8.12 W, 148 fs at 2.8 μm with a repetition rate of 69.65 MHz are achieved. To the best of our knowledge, this is the highest average power ever achieved from a femtosecond MIR laser source. Such a compact ultrafast laser system is promising for a wide range of applications, such as medical surgery and material processing.
Germplasm innovation can provide materials for breeding sugarcane cultivars. Saccharum officinarum is the main source of high-sugar and high-yield genes in sugarcane breeding. ‘Nobilization’ is the theoretical basis for exploiting S. officinarum, and S. officinarum authenticity directly affects sugarcane nobility breeding efficiency. Herein, the authenticity of 22 SLC-series S. officinarum clones imported from Sri Lanka and preserved in the China National Germplasm Repository of Sugarcane (NGRS) was explored by four-primer amplification-arrested mutation PCR (ARMS PCR) and somatic chromosome number counting. The amplified bands from SLC 08 120 and SLC 08 131 were the same with those from S. officinarum clone Badila, i.e. a common band of 428 bp and a S. officinarum-specific band of 278 bp, hence they were tentatively assigned as S. officinarum clones. The other 20 SLC clones had both 278 bp (S. officinarum-specific) and 203 bp (S. spontaneum-specific) bands, which are hybrid characteristics. In addition, the chromosome numbers of SLC 08 120 and SLC 08 131 are both 80, belong to typical S. officinarum. While the chromosome numbers of the other 20 materials are ranging from 101 to 129, consistent with hybrids of S. officinarum and S. spontaneum. This molecular cytological characterization indicates that among the 22 introduced SLC-series clones, only two, SLC 08 120 and SLC 08 131, were S. officinarum. Future agronomic trait and resistance analyses could facilitate their use as crossing parents in sugarcane breeding.
Previous observational studies have reported potential associations among attention-deficit/hyperactivity disorder (ADHD), obesity, and diabetes (including type 1 and type 2 diabetes mellitus [T1DM/T2DM]). However, whether the association between ADHD and diabetes is mediated by obesity is unknown.
With two-sample Mendelian randomization, we analysed the causal effect of ADHD on T1DM and T2DM and six obesity-related traits [including body mass index, waist circumference (WC), hip circumference, waist-to-hip ratio (WHR), body fat percentage and basal metabolic rate] and the causal effect of these obesity-related traits on T1DM/T2DM. Finally, with multivariable Mendelian randomization, we explored and quantified the possible mediation effects of obesity-related traits on the causal effect of ADHD on T1DM/T2DM.
Our results showed that ADHD increased the risk of T2DM by 14% [odds ratio (OR) = 1.140, 95% confidence interval (CI) = 1.005–1.293] but with no evidence of an effect on T1DM (OR = 0.916, 95% CI = 0.735–1.141, P = 0.433.). In addition, ADHD had a 6.1% increased causal effect on high WC (OR = 1.061, 95% CI = 1.024–1.099, P = 0.001) and an 8.2% increased causal effect on high WHR (OR = 1.082, 95% CI = 1.035–1.131, P = 0.001). In addition, a causal effect of genetically predicted high WC (OR = 1.870, 95% CI = 1.594–2.192, P < 0.001) on a higher risk of T2DM was found. In further analysis, WC mediated approximately 26.75% (95% CI = 24.20%–29.30%) of the causal association between ADHD and T2DM.
WC mediates a substantial proportion of the causal effect of ADHD on the risk of T2DM, which indicated that the risk of T2DM induced by ADHD could be indirectly reduced by controlling WC as a main risk factor.