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This paper presents a low-profile miniaturized dual-band antenna utilizing the quarter-mode substrate integrated waveguide (QMSIW) structure. The two modes of TE110 and TE220 of a single QMSIW structure are employed, enabling a dual-band operation. The frequency ratio between the two bands can be tuned by loading a capacitive structure, which is comprised of a capacitive-loaded patch and a short circuit post, inside the QMSIW structure. By introducing parasitic QMSIW structures through magnetic coupling, a dual-band antenna with enhanced bandwidths is achieved. The antenna has dimensions of smaller than 400 mm2 (0.048λL2) with a uniform height of 1.4 mm (0.016λL). Measurement results indicate that the −6 dB impedance bandwidths of the antennas can cover the 5G N78 (3.3–3.6 GHz) and N79 (4.8–5 GHz) bands, and the average efficiencies is better than −2.5 dB. To the authors’ knowledge, the proposed designs offer dual-wideband operation while having the smallest planar dimension compared to the previously reported antennas. Furthermore, an extended electric coupling dual-band antenna configuration is also described and measured, which achieves similar bandwidth extension as the proposed antenna.
While there is evidence that childhood maltreatment (CM) is positively associated with drug use (DU), the strength and difference of the association between CM and its subtypes (hereafter CM + ST) and DU remains to be further explored. A multilevel meta-analysis was conducted on 101 independent studies reporting 333 effect sizes (N = 132,341; Mage = 24.65; 43.80%males). Results showed significantly positive correlations between CM + ST and DU (range from 0.109 to 0.185). The results of the subgroup analysis revealed notable disparities in the correlations between distinct CM subtypes and DU (F = 5.358, P<0.01). Specifically, the effect size for childhood sexual abuse (CSA) was significantly lower than childhood emotional maltreatment (CEM) and childhood physical maltreatment (CPM), while no significant difference was noted between the CEM and CPM groups. These effect sizes also varied across regions, drug types, gender, detection rate of CM, the presence or absence of alcohol in substances, publication status and measurement method. The significant yet differing correlations between different subtypes of CM and DU to some extent support the principle of equality in psychopathology. These findings help explain the relationship between CM + ST and DU laying the groundwork for further research into the intricate and complex associations between CM and DU.
Prior observational studies have reported the potential protective effect of n-3 fatty acids on the prognosis of acute pancreatitis (AP). However, the causal impact of n-3 fatty acids on AP is unclear. We aimed to investigate further the association of n-3 fatty acids with AP. We performed a meta-analysis and Mendelian randomisation (MR) to explore the association between n-3 fatty acids and the prognosis of AP from clinical observation and genetics perspectives, respectively. Nine randomised controlled trials were included in this study. The result meta-analysis showed that complementary therapy of n-3 fatty acids significantly decreased mortality (Relative Risk (RR): 0·30; 95 % CI 0·14, 0·65, P < 0·05) and infectious complications in AP (RR: 0·45; 95 % CI 0·27, 0·77, P < 0·05). Compared with the control groups, the hospital stays (MD: −1·02; 95 % CI −1·85, −0·20, P < 0·05) in AP patients with n-3 fatty acids treatment were statistically reduced. However, the ICU stay (MD: −0·49; 95 % CI −1·29, −0·31, P > 0·05) between control groups and AP patients with n-3 fatty acids treatment was insignificant. Utilising genetic susceptibility analysis in the MR approach, the MR showed n-3 fatty acids have a significant causal effect on the AP risk (OR, 0·887; 95 % CI 0·797, 0·986, P = 0·027, fixed-effect; OR, 0·887; 95 % CI 0·792, 0·993, P = 0·037, random-effect). n-3 fatty acids complementary therapy may improve the prognosis of AP. Furthermore, genetically predicted serum levels of n-3 fatty acids can significantly lower AP risk.
Understanding the genetic basis of porcine mental health (PMH)-related traits in intensive pig farming systems may promote genetic improvement animal welfare enhancement. However, investigations on this topic have been limited to a retrospective focus, and phenotypes have been difficult to elucidate due to an unknown genetic basis. Intensively farmed pigs, such as those of the Duroc, Landrace, and Yorkshire breeds, have undergone prolonged selection pressure in intensive farming systems. This has potentially subjected genes related to mental health in these pigs to positive selection. To identify genes undergoing positive selection under intensive farming conditions, we employed multiple selection signature detection approaches. Specifically, we integrated disease gene annotations from three human gene–disease association databases (Disease, DisGeNET, and MalaCards) to pinpoint genes potentially associated with pig mental health, revealing a total of 254 candidate genes related to PMH. In-depth functional analyses revealed that candidate PMH genes were significantly overrepresented in signaling-related pathways (e.g., the dopaminergic synapse, neuroactive ligand‒receptor interaction, and calcium signaling pathways) or Gene Ontology terms (e.g., dendritic tree and synapse). These candidate PMH genes were expressed at high levels in the porcine brain regions such as the hippocampus, amygdala, and hypothalamus, and the cell type in which they were significantly enriched was neurons in the hippocampus. Moreover, they potentially affect pork meat quality traits. Our findings make a significant contribution to elucidating the genetic basis of PMH, facilitating genetic improvements for the welfare of pigs and establishing pigs as valuable animal models for gaining insights into human psychiatric disorders.
Research findings based on the data of current automatic identification systems (AISs) can only be applied to some parts of navigation research owing to their insufficient mining depth. Previously, route planning research has been based on the waypoint and corresponding optimised algorithm without considering the actual navigation situation and sailing habits. The planned route considerably differs from the actual sailing route, and the application result is undesirable. A novel solution to support the route planning problem has been introduced owing to the large accumulation of AIS big data. In this study, the ship navigable route framework (SNRF) which is reflected by real data via mining AIS big data serves as the basic network for the planned maritime route. This study uses the concept of manifold distance based on AIS big data to build a maritime SNRF through high-density searching. It can provide basic theoretical support for actual navigation distance calculation, route planning and route accessibility inspection in the future.
Natural clays are often employed as substrates for heterogeneous catalysts. However, the direct use of raw clays as catalysts has received less research attention. The objective of the present study was to help fill this gap by investigating catalytic properties of raw pelagic clays (PC) collected from the Indian Ocean. The raw PC were discovered to be efficient catalysts in the reduction of 4-nitrophenol (4-NP) in the presence of NaBH4. The effects of parameters including pH values, dosages of PC, and initial concentration of 4-NP and NaBH4 on the conversion or degradation rate of 4-NP have been investigated. The 4-NP was observed to be completely degraded within 480 s under conditions of 0.10 mM 4-NP, 25.0 mM NaBH4, and 0.20 g/L PC at an initial pH value of 7.0. The apparent rate constant was evaluated to be 27.53 × 10–3 s–1. Unlike previous pseudo-first order kinetics experiments, the induction period and degradation stages were observed to occur simultaneously during the PC catalysis. The S-shaped kinetics for 4-NP conversion was found to be perfectly matched by Fermi's function, and the enzyme-like catalysis by PC was appointed to describe the kinetics. Species of Fe(III), Mn(IV), and Mn(III) in PC were found to be essential, and were partly reduced to Fe(0) and Mn(II) by NaBH4 in our reaction, contributing to rapid conversion of 4-NP to 4-aminophenol (4-AP). The raw PC was converted to magnetic PC (m-PC) particles, which made PC particles separate easily for cycling use. This discovery would also have applications in continuous flow-fluid catalysis.
The stability, dispersion, and rheological properties of clay suspensions are important in the process of drilling. Organic clays were obtained traditionally by cation exchange, which is thermally unstable due to weak electrostatic interaction between the cationic surfactant and clay minerals. The purpose of the present study was to yield a stable and well dispersed organic bentonite (OBent) as a rheological additive for oil-based drilling mud. The co-modified method was used to modify bentonite by a cationic surfactant (cetyltrimethoxyammonium bromide: CTAB) and a silane coupling agent (hexadecyltrimethoxysilane: HDTMS). Firstly, the basal spacing of bentonite was enlarged by intercalation of CTAB, and the thermal stability of bentonite was improved by covalent bonds of HDTMS onto the bentonite platelets. The as-prepared OBent was characterized by infrared analysis, X-ray diffraction analysis, thermogravimetric analysis, and scanning electron microscopy. The hydrophobicity, solubility, viscosity, and tribological performance of the OBent were also recorded. The test results showed that the hydrophobicity of the co-modified bentonite was improved significantly, and was greater than that of bentonite modified with single surfactant CTAB or HDTMS. The bentonite modified by the surfactant together with the silane coupling agent had stable rheology and a lower coefficient of friction than the single surfactant-modified bentonite because more HDTMS entered into the interlayer spaces and formed chemical bonds at the inner surface of platelets.
Currently, most wheel-legged robots need to complete the switching of the wheel-and-leg modal in a stationary state, and the existing algorithms of statically switching the wheel-leg modal cannot meet the control requirements of multimodal switching dynamically for robots. In this paper, to achieve efficient switching of the wheel-and-leg modal for a quadruped robot, the novel transformable mechanism is designed. Then, a multimodal coordination operation control framework based on multiple algorithms is presented, incorporating the minimum foot force distribution method (algorithm No.1), the minimum joint torque distribution method (algorithm No.2), and the method of combining the single rigid body dynamic model with quadratic programming (algorithm No.3). In the process of switching wheel-leg modal dynamically, the existing algorithm No.3 is prone to produce the wrong optimal force due to the change of the whole-body rotational inertia. Therefore, an improved algorithm No.1 and algorithm No.2 are proposed, which do not consider the change in the body’s inertia. The control effects of the three algorithms are compared and analyzed by simulation. The results show that algorithm No.3 can maintain a small error in attitude angle and speed tracking regardless of whether the robot is under multilegged support or omnidirectional walking compared to the other two algorithms. However, proposed algorithms No.1 and No.2 can more accurately track the target speed when the robot is walking with wheels raising and falling. Finally, a multi-algorithm combination control scheme formulated based on the above control effects has been demonstrated to be effective for the dynamic switching of the wheel-and-leg modal.
This paper proposes a linear quadratic approximation approach to dynamic nonlinear rationally inattentive control problems with multiple states and multiple controls. An efficient toolbox to implement this approach is provided. Applying this toolbox to five economic examples demonstrates that rational inattention can help explain the comovement puzzle in the macroeconomics literature.
Many rural youths in China receive a poor-quality, strict and exam-oriented education. In everyday and professional discourses, incorporating live-streaming technologies in rural schooling is tied to promises of improved educational quality and a narrowed urban‒rural education gap. Reflecting a dystopian ideology of meritocracy, this article investigates how live-streaming technologies transmit suzhi (human quality) education and downplay the exam-oriented education with which rural students and teachers are familiar. The authors argue that the two educational vehicles for meritocracy work together to channel students to a seemingly meritocratic pathway of social mobility but funnel rural students to an inferior educational track according to their rural registration and lower-class backgrounds. The online version of suzhi education complicates and even exacerbates the already fierce educational competition that rural students face. Rural students’ low aspirations and their teachers’ apathy towards live-streaming classes challenge the purportedly transformative effects of live-streaming technologies in China's rural schooling.
In this study, aluminium fluoride trihydrate (AlF3⋅3H2O) was used to inhibit the sintering of calcined coal-series kaolin (CCSK). In addition, the oil absorption properties of CCSK were studied. The particle-size distribution, specific surface area and porosity of the samples were investigated as a function of calcination temperature and the addition of AlF3⋅3H2O. Moreover, the ability of AlF3⋅3H2O to improve the oil absorption of CCSK was explored. The morphology, structure and phase composition of the specimens were investigated using scanning electron microscopy and X-ray diffraction. The phase transition during heating of the samples was studied using thermogravimetric analysis. The preparation with 10 wt.% AlF3⋅3H2O had the optimal sintering inhibition effect on CCSK at 1000°C. The release of SiF4 gas during heating and the formation of mullite whiskers on the particle surface caused by AlF3⋅3H2O moderated the formation of molten-phase liquid bridges between particles and inhibited sintering of the raw material powder. Furthermore, the formation of submicron mullite whiskers on the surface of the CCSK particles enhanced the oil-absorption properties of the sample significantly.
According to the public data collected from the Health Commission of Gansu Province, China, regarding the COVID-19 pandemic during the summer epidemic cycle in 2022, the epidemiological analysis showed that the pandemic spread stability and the symptom rate (the number of confirmed cases divided by the sum of the number of asymptomatic cases and the number of confirmed cases) of COVID-19 were different among 3 main epidemic regions, Lanzhou, Linxia, and Gannan; both the symptom rate and the daily instantaneous symptom rate (daily number of confirmed cases divided by the sum of daily number of asymptomatic cases and daily number of confirmed cases) in Lanzhou were substantially higher than those in Linxia and Gannan. The difference in the food sources due to the high difference of the population ethnic composition in the 3 regions was probably the main driver for the difference of the symptom rates among the 3 regions. This work provides potential values for prevention and control of COVID-19 in different regions.
High-speed water entry is a transient hydrodynamic process that is accompanied by strongly compressible flow, free surface splash, cavity evolution and other nonlinear hydrodynamic phenomena. To address these problems, a novel fluid–structure interaction (FSI) scheme based on the immersed boundary method is proposed which is suitable for strongly compressible multiphase flows. In this scheme, considering the multiphase interfaces at the immersed boundary, an improved immersed boundary method for effectively suppressing the non-physical force oscillation is proposed. Additionally, a quaternion-based six degrees of freedom motion system is used to describe rigid body motion, and the multiphase flow Eulerian finite element method is applied as the fluid solver. Using analytical solutions, experimental data and literature data, the accuracy and robustness of the FSI scheme are validated. Finally, the high-speed water entry of the slender body with different noses is investigated, and the hydrodynamic loads including the axial and normal drag forces and the bending moment are extensively discussed. The hydrodynamic load and motion trajectory are determined by the nose configuration. The tail slamming phenomenon is the primary focus, and it is revealed that its formation is primarily related to the pitch moment formed at the stage of crossing the free surface. Tail slamming also causes violent impact loads, especially bending moments, which may cause slender projectiles to break off. Finally, to combine the features of the flat and hemispherical noses, the water entry of the projectile with a truncated hemispherical nose is simulated and discussed.
We first establish a lower bound on the size and spectral radius of a graph G to guarantee that G contains a fractional perfect matching. Then, we determine an upper bound on the distance spectral radius of a graph G to ensure that G has a fractional perfect matching. Furthermore, we construct some extremal graphs to show all the bounds are best possible.
The southern Great Xing’an Range (SGXR), located in the eastern segment of the Central Asian Orogenic Belt (CAOB), is one of the most economically important Cu–Mo–Fe–Sn–Pb–Zn–Ag metallogenic provinces in China. The newly discovered Panjiaduan Cu–Pb–Zn deposit (9.3 Mt; at 1.36% Cu, 2.90% Pb, 3.80% Zn and 38.12 g/t Ag), located in the SE segment of the SGXR, is primarily hosted in fracture zones in volcanic rocks and granodiorite of the Manitu Formation. Four paragenetic stages of metallic mineralization are identified: (I) quartz-pyrite-arsenopyrite; (II) quartz-polymetallic sulphide; (III) quartz-galena-sphalerite-argentite; and (IV) quartz-calcite-minor sulphide. The hydrothermal quartz contains three types of primary fluid inclusion (FIs): vapour-rich two-phase liquid-vapour (LV-type), liquid-rich two-phase liquid-vapour (VL-type) and three-phase liquid-vapour-solid FIs (SL-type). Stages I and II contain all types with homogenization temperatures (Th) of 324–386 °C and 276–334 °C as well as salinities of 0.7–38.0 wt% and 0.9–34.7 wt%, respectively, whereas stage III is composed of VL- and LV-type FIs with Th of 210–269 °C and salinities of 0.5–7.2 wt%. Only VL-type FIs occur in stage IV, with Th of 139–185 °C and salinities of 1.6–4.2 wt%. The δ18OH2O and δD values vary from −15.7 to 2.6‰ and −132.7 to −110.2‰, respectively, indicating predominant meteoric water with an initial magmatic source. The He–Ar isotopic compositions of the pyrite inclusions from the Panjiaduan Cu–Pb–Zn veins suggest that fluids were derived from the crust.
This paper presents a deep-learning-based workflow to detect synapses and predict their neurotransmitter type in the primitive chordate Ciona intestinalis (Ciona) electron microscopic (EM) images. Identifying synapses from EM images to build a full map of connections between neurons is a labor-intensive process and requires significant domain expertise. Automation of synapse classification would hasten the generation and analysis of connectomes. Furthermore, inferences concerning neuron type and function from synapse features are in many cases difficult to make. Finding the connection between synapse structure and function is an important step in fully understanding a connectome. Class Activation Maps derived from the convolutional neural network provide insights on important features of synapses based on cell type and function. The main contribution of this work is in the differentiation of synapses by neurotransmitter type through the structural information in their EM images. This enables the prediction of neurotransmitter types for neurons in Ciona, which were previously unknown. The prediction model with code is available on GitHub.
Hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) is a severe and life-threatening complication, characterised by multi-organ failure and high short-term mortality. However, there is limited information on the impact of various comorbidities on HBV-ACLF in a large population. This study aimed to investigate the relationship between comorbidities, complications and mortality. In this retrospective observational study, we identified 2166 cases of HBV-ACLF hospitalised from January 2010 to March 2018. Demographic data from the patients, medical history, treatment, laboratory indices, comorbidities and complications were collected. The mortality rate in our study group was 47.37%. Type 2 diabetes mellitus was the most common comorbidity, followed by alcoholic liver disease. Spontaneous bacterial peritonitis, pneumonia and hepatic encephalopathy (HE) were common in these patients. Diabetes mellitus and hyperthyroidism are risk factors for death within 90 days, together with gastrointestinal bleeding and HE at admission, HE and hepatorenal syndrome during hospitalisation. Knowledge of risk factors can help identify HBV-ACLF patients with a poor prognosis for HBV-ACLF with comorbidities and complications.
In this paper, we show that the permeability of a porous material (Tartar (1980)) and that of a bubbly fluid (Lipton and Avellaneda. Proc. R. Soc. Edinburgh Sect. A: Math. 114 (1990), 71–79) are limiting cases of the complexified version of the two-fluid models posed in Lipton and Avellaneda (Proc. R. Soc. Edinburgh Sect. A: Math. 114 (1990), 71–79). We assume the viscosity of the inclusion fluid is $z\mu _1$ and the viscosity of the hosting fluid is $\mu _1\in \mathbb {R}^{+}$, $z\in \mathbb {C}$. The proof is carried out by the construction of solutions for large $|z|$ and small $|z|$ with an iteration process similar to the one used in Bruno and Leo (Arch. Ration. Mech. Anal. 121 (1993), 303–338) and Golden and Papanicolaou (Commun. Math. Phys. 90 (1983), 473–491) and the analytic continuation. Moreover, we also show that for a fixed microstructure, the permeabilities of these three cases share the same integral representation formula (3.17) with different values of contrast parameter $s:=1/(z-1)$, as long as $s$ is outside the interval $\left [-\frac {2E_2^{2}}{1+2E_2^{2}},-\frac {1}{1+2E_1^{2}}\right ]$, where the positive constants $E_1$ and $E_2$ are the extension constants that depend only on the geometry of the periodic pore space of the material.
Subthreshold depression (sD) negatively impacts well-being and psychosocial function and is more prevalent compared with major depressive disorder (MDD). However, as adults with sD are less likely to seek face-to-face intervention, internet-based cognitive-behavioral therapy (ICBT) may overcome barriers of accessibility to psychotherapy. Although several trials explored the efficacy of ICBT for sD, the results remain inconsistent. This study evaluated whether ICBT is effective in reducing depressive symptoms among Chinese adults with sD.
Methods
A randomized controlled trial was performed. The participants were randomly assigned to 5 weeks of ICBT, group-based face-to-face cognitive-behavioral therapy (CBT), or a waiting list (WL). Assessments were conducted at baseline, post-intervention and at a 6-month follow-up. The primary outcome measured depressive symptoms using the Center for Epidemiological Studies Depression Scale (CES-D). Outcomes were analyzed using a mixed-effects model to assess the effects of ICBT.
Results
ICBT participants reported greater reductions on all the outcomes compared to the WL group at post-intervention. The ICBT group showed larger improvement on the Patient Health Questionnaire-9 (PHQ-9) at post-intervention (d = 0.12) and at follow-up (d = 0.10), and with CES-D at post-intervention (d = 0.06), compared to the CBT group.
Conclusions
ICBT is effective in reducing depressive symptoms among Chinese adults with sD, and improvements in outcomes were sustained at a 6-month follow-up. Considering the low rates of face-to-face psychotherapy, our findings highlight the considerable potential and implications for the Chinese government to promote the use of ICBT for sD in China.