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A novel ionic liquid/α-ZrP (C16MIM/α-ZrP) lamellar nanocomposite was fabricated via the electrostatic self-assembly deposition technique by using exfoliated α-ZrP nanosheets and guest molecules (1-hexadecyl-3-methylimidazolium bromide) as building blocks under mild conditions. C16MIM/α-ZrP nanocomposite was characterized by various analytical techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier transform infrared spectroscopy, and synchronous thermal analyzer. The net interlayer spacing of α-ZrP determined by XRD confirmed that the C16MIM cations formed a monolayer arrangement between the α-ZrP nanosheets. The morphology and microstructure of C16MIM/α-ZrP composite were observed using SEM and TEM. The C16MIM/α-ZrP modified glass carbon electrode exhibited excellent electrocatalytic activity toward the oxidation of nitrite in weak base media. The results obtained with differential pulse voltammetry demonstrated that the C16MIM/α-ZrP hybrid detected nitrite linearly in the concentration range from 7.3 μM to 1.25 mM with the detection limit of 1.26 μM (S/N = 3). Additionally, the prepared sensor showed outstanding reproducibility, high stability, and anti-interference capability.
Al-based composites with micrometer and submicro-TiB2 reinforcements (1 wt%) have been produced by selective laser melting (SLM) from mixed powder under different processing conditions. The results show that the densification level of SLM-processed composite with submicro-TiB2 particles (>99.0%) was 0.3–2.4% larger than that of micrometer TiB2-reinforced composite under the same processing conditions. The distribution of Si precipitates in the matrix experienced a transform from continuous cellular to directional line-like morphology with reinforcement size decreasing from micron to submicron. The reinforcement size added in the matrix also exhibited a critical influence on preferred orientation and grain size of matrix. The SLM-processed composites exhibited improved tensile strength and ductility with a decrease of reinforcement size. High tensile strength of ∼400 MPa and elongation of ∼3.6% were obtained for the fine TiB2-reinforced samples, increasing by 6 and 13% compared with that of micro-TiB2–added samples, respectively.
Some recent studies examined the effect of ambient particulate matter (PM) pollution on depression and suicide. However, the results have been inconclusive.
To determine the overall relationship between PM exposure and depression/suicide in the general population.
We conducted a systematic review and meta-analysis of case-crossover and cohort studies to assess the association between PM2.5 (particles with an aerodynamic diameter of 2.5 µm or less) or PM10 (particles with an aerodynamic diameter between 2.5 and 10 µm) exposure and depression/suicide.
A total of 14 articles (7 for depression and 7 for suicide) with data from 684 859 participants were included in the meta-analysis. With a 10 µg/m3 increase in PM2.5 we found a 19% (odds ratio [95% CI] 1.19 [1.07, 1.33]) increased risk of depression and a marginally increased risk of suicide (odds ratio [95% CI] 1.05 [0.99, 1.11]) in the general population. We did not observe any significant associations between increasing exposure to PM10 and depression/suicide. Sensitivity and subgroup analyses were used to determine the robustness of results. The strongest estimated effect of depression associated with PM2.5 appeared in a long-term lag pattern (odds ratio [95% CI] 1.25 [1.07, 1.45], P < 0.01) and cumulative lag pattern (odds ratio [95% CI] 1.26 [1.07, 1.48], P < 0.01).
The meta-analysis suggested that an increase in ambient PM2.5 concentration was strongly associated with increased depression risk in the general population, and the association appeared stronger at long-term lag and cumulative lag patterns, suggesting a potential cumulative exposure effect over time.
The present study was undertaken to investigate the antiparasitic activity of extracellular products of Streptomyces albus. Bioactivity-guided isolation of chloroform extracts affording a compound showing potent activity. The structure of the compound was elucidated as salinomycin (SAL) by EI-MS, 1H NMR and 13C NMR. In vitro test showed that SAL has potent anti-parasitic efficacy against theronts of Ichthyophthirius multifiliis with 10 min, 1, 2, 3 and 4 h (effective concentration) EC50 (95% confidence intervals) of 2.12 (2.22–2.02), 1.93 (1.98–1.88), 1.42 (1.47–1.37), 1.35 (1.41–1.31) and 1.11 (1.21–1.01) mg L−1. In vitro antiparasitic assays revealed that SAL could be 100% effective against I. multifiliis encysted tomonts at a concentration of 8.0 mg L−1. In vivo test demonstrated that the number of I. multifiliis trophonts on Erythroculter ilishaeformis treated with SAL was markedly lower than that of control group at 10 days after exposed to theronts (P < 0.05). In the control group, 80% mortality was observed owing to heavy I. multifiliis infection at 10 days. On the other hand, only 30.0% mortality was recorded in the group treated with 8.0 mg L−1 SAL. The median lethal dose (LD50) of SAL for E. ilishaeformis was 32.9 mg L−1.
The musk deer (Moschus berezovskii) is an economically important species from which musk is extracted and used in perfumes and medicines. Cestodes (parasitic flatworms) of the genus Moniezia are important parasites that infect this endangered species and can cause high mortality in young deer. In 1982, Moniezia (S.) sichuanensis sp. nov. was described from a specimen obtained from wild musk deer. The new species was distinct from the other described species of Moniezia by the sawtooth-shaped interproglottidal glands, the thick vagina and the absence of a cirrus spine. In the present study, 12 cestodes collected from musk deer were examined morphologically and confirmed to be M. sichuanensis. Molecular characterization was performed by amplifying and comparing the internal transcribed spacer 1 (ITS1) and 5.8S rRNA gene (ITS1–5.8S) of ribosomal DNA with available sequences from other Moniezia species. The amplified sequences ranged from 761 to 764 bp and similarity ranged from 98.7–100%, compared to 67.8–92.4% with other Moniezia spp. Construction of a phylogenetic tree using the neighbour-joining method indicated that all 12 ITS1–5.8S sequences formed a single clade, confirming M. sichuanensis as a separate species. This study provides novel molecular insight into M. sichuanensis that could prove useful for future diagnosis and control of monieziasis in musk deer.
The morphology, composition, and structure of precipitates in an Al–Si–Mg–Hf alloy after heat treatment at 560°C for 20 h were studied by means of Cs-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), energy dispersive X-ray spectrometry (EDS), high-resolution transmission electron microscopy (HRTEM), and first-principle calculations. Precipitates with three kinds of morphologies were observed. The rectangular and square precipitates were predominantly (Si2−xAlx)Hf phases, while the nanobelt-like precipitate is the Si2Hf phase. First-principle calculations were used to show that the Si6 and Si8 sites were the most favorable sites for Al incorporation in the orthorhombic Si2Hf phase.
Selective laser melting (SLM) technology efficiently solves the current manufacturing challenges of high-performance porous structure components, due to its freeform fabrication principle. As the most basic and crucial structure element, the nodes of porous structure component play an important role in its mechanical property. In this study, finite element method was used to investigate the thermal behavior during SLM processing of micro-scale node-structure. The dynamic size of molten pool was continuously predicted and consequently the typical “necking” effect was found, which was consistent with the experiment results. Besides, the influence of laser scan speed on temperature and temperature gradient of molten pool was also analyzed. The results indicated that the “necking” effect became more conspicuous with the applied scan speed increasing, which significantly deteriorated the mechanical property of porous structure components.
With more users, more mobile phones and tablets, more connections to homes and offices, and richer content sharing over wireless communication networks, the industry is facing an exponential increase in mobile broadband traffic in the frequency spectrum from 700 MHz to 2.6 GHz. To meet this demanding challenge, an intuitive idea is to add more licensed spectrum, which would ensure predictable performance in terms of mobility. However, for various reasons, it is possible that sufficient additional licensed spectrum will not be available in the near future. On the other hand, the amount of unlicensed spectrum already assigned or planned to be assigned is comparable or even more than the licensed spectrum. By taking full advantage of the unlicensed spectrum, the burden on the licensed spectrum can be relieved. Unlicensed spectrum has already been utilized in multiple technologies, such as Wi-Fi and Bluetooth, and now there is a new member of the unlicensed family at 5 GHz for mobile broadband. By extending the benefits of Long Term Evolution-Advanced (LTE-A) to the unlicensed spectrum, we can boost the capacity, while maintaining seamless mobility and predictable performance.
Although it has great potential, LTE-Unlicensed is still in its infancy and faces some major challenges. Only by careful design can the LTE-Unlicensed technique truly benefit us with tremendous advantages. Thus, in this chapter, we give a comprehensive introduction to the benefits and design principles of LTE-Unlicensed. In addition, two specific implementation cases are provided for illustration purposes. This chapter is organized as follows. In Section 20.1, the motivation for proposing the LTE-Unlicensed technique will be stated. Then the design challenges in and potential solutions for LTE-Unlicensed will be discussed in Section 20.2. Two distributed resource allocation applications utilizing matching-based approaches will be introduced in Section 20.3. Finally, conclusions are drawn in Section 20.4.
Currently, technologies such as IEEE 802.11 (Wi-Fi), 802.15.1 (Bluetooth), and 802.15.4 (ZigBee) are implemented in the 2.4 GHz ISM (Industry, Scientific, and Medical) and 5 GHz U-NII (Unlicensed National Information Infrastructure) bands, more commonly referred to as the unlicensed bands. Some operators have deployed a large number of Wi-Fi access points (APs) to offload cellular traffic to the unlicensed spectrum. Wi-Fi offloading strikes a trade-off between capacity and performance.
The purpose of the present study was to do a psychometric evaluation of the somatic and psychological health report (SPHERE) among Chinese adolescents. Our participants were 116 twins (50 females). Psychometric evaluation indicated that the reliability and validity of this scale were good. The internal consistencies and split-half reliabilities of all subscales were above 0.80. Furthermore, the item-total correlations were acceptable for all the subscales (all the values were higher than 0.20). The present findings suggest that the SPHERE can be well used to measure Chinese adolescents’ somatic and psychological health.
The objective of this study was to explore the expression of urotensin II (UII), its receptor (GPR14), and vascular endothelial growth factor (VEGF), as well as their associations in the ischaemic brains of rats with focal cerebral ischaemia, under normal and diabetic conditions.
Diabetes mellitus (DM) was induced by injection of streptozotocin (STZ) into Sprague—Dawley rats. Focal cerebral ischaemia was induced by middle cerebral artery occlusion (MCAO) four weeks after DM onset by STZ. Rats (n=80) were divided into four groups: normal control, DM, MCAO, and DM/MCAO. Immunohistochemistry and reverse-transcriptase-polymerase chain reaction (RT-PCR) were used to detect the expression of UII, GPR14 and VEGF in the diabetic and ischaemic brain.
Expression of UII and GPR14 was increased at mRNA and protein levels in the DM and MCAO group compared with controls. In the DM/MCAO group, expression of UII and GPR14 was increased significantly in the ischaemic brain, and was accompanied by a significantly increased VEGF expression.
Diabetes mellitus was seen to aggravate brain lesions after ischaemia, and UII may have an important role.
Severe fever with thrombocytopenia syndrome virus (SFTSV) has been prevalent for some time in China and it was first identified in 2010. However, the seroprevalence of SFTSV in the general population in southeastern China and risk factors associated with the infection are currently unclear. Blood samples were collected from seven counties across Zhejiang province and tested for the presence of SFTSV-specific IgG antibodies by ELISA. A total of 1380 blood samples were collected of which 5·51% were seropositive for SFTSV with seroprevalence varying significantly between sites. Seroprevalence of SFTSV in people who were family members of the patient, lived in the same village as the patient, or lived in a different village than the patient varied significantly. There was significant difference in seroprevalence between participants who bred domestic animals and participants who did not. Domestic animals are probably potential reservoir hosts and contact with domestic animals may be a transmission route of SFTSV.
Three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging of the inner ear after intratympanic injection of gadolinium, together with magnetic resonance imaging scoring of the perilymphatic space, were used to investigate the positive identification rate of hydrops and determine the technique's diagnostic value for delayed endolymphatic hydrops.
Twenty-five patients with delayed endolymphatic hydrops underwent pure tone audiometry, bithermal caloric testing, vestibular-evoked myogenic potential testing and three-dimensional magnetic resonance imaging of the inner ear after bilateral intratympanic injection of gadolinium. The perilymphatic space of the scanned images was analysed to investigate the positive identification rate of endolymphatic hydrops.
According to the magnetic resonance imaging scoring of the perilymphatic space and the diagnostic standard, 84 per cent of the patients examined had endolymphatic hydrops. In comparison, the positive identification rates for vestibular-evoked myogenic potential and bithermal caloric testing were 52 per cent and 72 per cent respectively.
Three-dimensional magnetic resonance imaging after intratympanic injection of gadolinium is valuable in the diagnosis of delayed endolymphatic hydrops and its classification. The perilymphatic space scoring system improved the diagnostic accuracy of magnetic resonance imaging.
Increased intra-individual variability (IIV) in reaction time (RT) across various tasks is one ubiquitous neuropsychological finding in attention deficit hyperactivity disorder (ADHD). However, neurobiological underpinnings of IIV in individuals with ADHD have not yet been fully delineated. The ex-Gaussian distribution has been proved to capture IIV in RT. The authors explored the three parameters [μ (mu), σ (sigma), τ (tau)] of an ex-Gaussian RT distribution derived from the Conners' continuous performance test (CCPT) and their correlations with the microstructural integrity of the frontostriatal–caudate tracts and the cingulum bundles.
We assessed 28 youths with ADHD (8–17 years; 25 males) and 28 age-, sex-, IQ- and handedness-matched typically developing (TD) youths using the CCPT, Wechsler Intelligence Scale for Children, 3rd edition and magnetic resonance imaging (MRI). Microstructural integrity, indexed by generalized fractional anisotropy (GFA), was measured by diffusion spectrum imaging tractrography on a 3-T MRI system.
Youths with ADHD had larger σ (s.d. of Gaussian distribution) and τ (mean of exponential distribution) and reduced GFA in four bilateral frontostriatal tracts. With increased inter-stimulus intervals of CCPT, the magnitude of greater τ in ADHD than TD increased. In ADHD youths, the cingulum bundles and frontostriatal integrity were associated with three ex-Gaussian parameters and with μ (mean of Gaussian distribution) and τ, respectively; while only frontostriatal GFA was associated with μ and τ in TD youths.
Our findings suggest the crucial role of the integrity of the cingulum bundles in accounting for IIV in ADHD. Involvement of different brain systems in mediating IIV may relate to a distinctive pathophysiological processing and/or adaptive compensatory mechanism.
The poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) based ferroelectric and relaxor materials have been proved to be good electrocaloric (EC) materials. To further enhance the EC effect in ferroelectric relaxor terpolymer poly(vinylidene fluoride–trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE)), composites such as polymer-polymer blends and nanocomposites filled with inorganic nanoparticles are fabricated and investigated. It is found that the addition of small amount of filler (such as P(VDF-TrFE) or nano-ZrO2) can increase terpolymer’s crystallinity and enhance its relaxor behavior through interface couplings. The increased crystallinity and enhanced relaxor behavior together result in enhanced electrocaloric effect. The results demonstrate the promise of composite approaches in tailoring and enhancing ECE in the relaxor terpolymers.