Whole-rock major and trace elements, together with zircon U–Pb and Hf-isotope data, are reported for the granitic intrusions in the central part of the Jiamusi–Khanka Massif in the eastern segment of ...the Central Asian Orogenic Belt (CAOB), in order to investigate their precise geochronological framework, petrogenesis, sources and tectonic implications. LA-ICP-MS zircon U–Pb data, combined with previous ages, indicate that the Jiamusi–Khanka Massif is dominated by three stages of granitic magmatism, i.e., Cambrian (530–493Ma), Permian (299–254Ma) and Late Triassic (223–212Ma), with two possible subordinate magmatic events that occurred in the Silurian (434–416Ma) and Carboniferous (331–317Ma). The Permian diorite and granodiorite contain high Al2O3 (15.81–19.07wt.%), Na2O (K2O/Na2O=0.25–0.44) and Sr (748–949ppm) contents and low Y (4–18ppm) and Yb (0.37–1.94ppm) contents, with high Sr/Y ratios of 54–207, indicating that they probably originated from partial melting of a mafic lower crust at high-pressure conditions. However, the coeval monzogranite and granite porphyry have higher SiO2, Y, Yb and HREE contents and lower Al2O3, Na2O/K2O ratio and Sr contents, together with the features of LILE-enriched, HFSE-depleted and Nb–Ta–Ti troughs, reflecting that they were likely produced by partial melting of arc-type crustal materials at a relatively shallow crustal level. Meanwhile, the Late Triassic granites contain high SiO2 (75.90–77.40wt.%) and K2O (4.17–4.87wt.%), combined with low Sr and high Y and HREE, suggesting that they were possibly generated from crustal materials with involvement of slab-derived fluids at low pressure. All the granitoids have high 176Hf/177Hf ratios (0.282518–0.282842) with Hf two-stage model ages of 2005–809Ma, and most of the magmatic zircons have positive εHf(t) values, indicating that the primary magmas of these rocks were derived from partial melting of a dominantly “old” source with a possible significant addition of juvenile materials. Based on the geochemical data and the regional geological investigations, we propose that the Jiamusi–Khanka Massif was an exotic block probably derived from Gondwana, which might be located in a relatively southerly place compared with the current position and faced the Paleo-Pacific Ocean during the Early Permian–Late Triassic time. The Permian granitoids would form in an active continental margin setting, whereas the Late Triassic granites were most likely generated within a local extensional environment, both of which were closely related to the westward subduction of the Farallon plate of the Paleo-Pacific Ocean beneath the Jiamusi–Khanka Massif.
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•Granitoids were emplaced at 530–493Ma, 299–254Ma and 223–212Ma.•Evidence for Precambrian crustal growth in the Jiamusi–Khanka Massif•Granitoids formed in distinct settings from active continental margin to extension
Previous studies have dedicated great efforts in elucidating the key factors on e-waste recycling intentions, however, most of them did not involve the discrepancy between recycling intention and ...actual recycling behavior. This study aims to explore the intention-behavior discrepancy and the role of consumers’ price sensitivity and proactive personality in the intention-behavior transformation toward recycling obsolete mobile phone. Results from a questionnaire survey administered in Jiangsu province confirmed the recycling intention-behavior discrepancy. In terms of focused psychological factors, the results showed that the dimension of “price importance” in price sensitivity has a negative moderating effect (β = −0.135,
p
< 0.05) on the recycling intention-behavior relationship, while the dimension of “price comparison” has a positive moderating effect (β = 0.095,
p
< 0.05) on the relationship between implementation intention and recycling behavior. Proactive personality positively moderates (β = 0.228,
p
< 0.001) the recycling intention-behavior relationship. A series of measures are then proposed to encourage consumers’ recycling behavior of obsolete mobile phones, including vigorously creating a more favorable atmosphere to help individuals overcome the external obstacles in recycling, further increasing formal recycling reward and enhancing consumers’ perceived value of formal recycling service, etc.
Neurosurgery is mainly for the treatment of head trauma, cerebrovascular disease, brain tumors, and spinal cord disorders. These operations are difficult and risky, so disability and mortality are ...high. To reduce the risk of surgery, reduce postoperative complications, and improve the treatment effect of patients, this article applies deep learning and microscopic imaging to the nursing process of neurosurgery. Through deep learning and microscopic imaging, doctors can learn about patients during surgery. The specific situation of the trauma site, after which surgery is performed according to the situation, effectively reduces the casualties, reduces the loss of patients, and provides a reference for the research of neurosurgery nursing. Research results prove that deep learning and microscopic imaging can play an important role in the nursing process of neurosurgery. Compared with conventional treatment methods, microscopic imaging treatment can effectively improve the treatment effect, and the operation time for patients is less than that of conventional treatment. About 20% and the incidence of postoperative complications is lower than 30%, which can effectively reduce the cost to patients and improve the quality of treatment.
•We investigated the anti-JEV effect of luteolin in vitro.•Luteolin exhibited antiviral activity against JEV.•Luteolin showed extracellular virucidal activity on JEV.•Luteolin inhibited JEV at the ...post-entry stage.
Japanese encephalitis virus (JEV), a member of family Flaviviridae, is a neurotropic flavivirus that causes Japanese encephalitis (JE). JEV is one of the most important causative agents of viral encephalitis in humans, and this disease leads to high fatality rates. Although effective vaccines are available, no effective antiviral therapy for JE has been developed. Hence, identifying effective antiviral agents against JEV infection is important. In this study, we found that luteolin was an antiviral bioflavonoid with potent antiviral activity against JEV replication in A549 cells with IC50=4.56μg/mL. Luteolin also showed extracellular virucidal activity on JEV. With a time-of-drug addition assay revealing that JEV replication was inhibited by luteolin after the entry stage. Overall, our results suggested that luteolin can be used to develop an antiviral drug against JEV.
Abstract In this work, the influence of solution treatment on the corrosion behavior and microstructure of HT-HAZ was studied. The results show that the balanced two-phase ratio is discovered after ...solution treatment. After solution treatment at 960°C, a small amount of chromium nitride remains at the two-phase interface and in the ferrite. With the solution treatment temperature increasing to 1120°C, chromium nitride can be fully dissolved. The chemical elements of the two-phase are redistributed during the solution treatment process, which results in changes in PREN. After solution treatment, the proportion of recrystallized grains increases whereas that of sub-structured grains decreases, indicating the reduction of residual stresses and deformations. The percentage of CSL boundaries increases as the solution treatment temperature rises. Compared with HT-HAZ without solution treatment, the improved corrosion resistance after solution treatment is ascribed to the balanced two-phase ratio, less chromium nitride precipitates, smaller residual deformations, and more CSL boundaries. However, the pitting resistance after solution treatment at 960°C is still relatively poor on account of the residual chromium nitride. The pitting nucleation sites are closely associated with the chromium nitride precipitates and PREN of two-phase.
Syndromic surveillance is an incipient approach to early wildlife disease detection. Consequently, systematic assessments are needed for methodology validation in wildlife populations.
We evaluated ...the sensitivity of a syndromic surveillance protocol for respiratory disease detection among chimpanzees in Gombe National Park, Tanzania. Empirical health, behavioural, and demographic data were integrated with an agent‐based, network model to simulate disease transmission and surveillance.
Surveillance sensitivity was estimated as 66% (95% CI: 63.1, 68.8%) and 59.5% (95% CI: 56.5%, 62.4%) for two monitoring methods (weekly count and prevalence thresholds respectively), but differences among calendar quarters in outbreak size and surveillance sensitivity suggest seasonal effects.
We determined that a weekly detection threshold of ≥2 chimpanzees with clinical respiratory disease leading to outbreak response protocols (enhanced observation and biological sampling) is an optimal algorithm for outbreak detection in this population.
Synthesis and applications. This is the first quantitative assessment of syndromic surveillance in wildlife, providing a model approach to detecting disease emergence. Coupling syndromic surveillance with targeted diagnostic sampling in the midst of suspected outbreaks will provide a powerful system for detecting disease transmission and understanding population impacts.
This is the first quantitative assessment of syndromic surveillance in wildlife, providing a model approach to detecting disease emergence. Coupling syndromic surveillance with targeted diagnostic sampling in the midst of suspected outbreaks will provide a powerful system for detecting disease transmission and understanding population impacts.
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Unique optical, electrical, and mechanical properties of continuous semiconductor helices with nanoscale and mesoscale dimensions represent a previously unexplored materials platform for various ...applications requiring near-infrared (NIR) optical activity. However, current methods of their synthesis limit the spectrum of chiral geometries, charge transport, and spectral response. Furthermore, the requirements of nearly perfect enantioselectivity, high uniformity, and high yield need to be attained as well. Here, we show that continuous semiconductor helices with tunable spectral response and high monodispersity can be made via self-assembly of semiconductor nanoparticles (NPs). Unraveling the interdependent effects of solvent, pH, ligand density, and coordination bridges between NPs allowed us to maximize the chiral bias for face-to-face particle–particle interactions, control of the geometry of the helices, and increase assembly efficiency by 3 orders of magnitude. The self-limiting nature of NP association results in consistency of their geometries over the entire synthetic ensemble. The helices show chiroptical activity across a broad range of wavelengths from 300 to 1300 nm, and the maximum/sign of their polarization rotation in NIR part can be modulated by varying their pitch. The method described in this study can be extended to chiral semiconductor materials from a variety of other NPs and their combinations.
A detailed study and comparison was made on the catalytic activities of cutinases from Humilica insolens (HiC), Pseudomonas mendocina (PmC), and Fusarium solani (FsC) using low-crystallinity (lc) and ...biaxially oriented (bo) poly(ethylene terephthalate) (PET) films as model substrates. Cutinase activity for PET hydrolysis was assayed using a pH-stat to measure NaOH consumption versus time, where initial activity was expressed as units of micromoles of NaOH added per hour and per milliliter of reaction volume. HiC was found to have good thermostability with maximum initial activity from 70 to 80 °C, whereas PmC and FsC performed best at 50 °C. Assays by pH-stat showed that the cutinases had about 10-fold higher activity for the lcPET (7% crystallinity) than for the boPET (35% crystallinity). Under optimal reaction conditions, initial activities of cutinases were successfully fit by a heterogeneous kinetic model. The hydrolysis rate constant k 2 was 7-fold higher for HiC at 70 °C (0.62 μmol/cm2/h) relative to PmC and FsC at 50 and 40 °C, respectively. With respect to PET affinity, PmC had the highest affinity, while FsC had the lowest value. In a 96 h degradation study using lcPET films, incubation with PmC and FsC both resulted in a 5% film weight loss at 50 and 40 °C, respectively. In contrast, HiC-catalyzed lcPET film hydrolysis at 70 °C resulted in a 97 ± 3% weight loss in 96 h, corresponding to a loss in film thickness of 30 μm per day. As degradation of lcPET progressed, crystallinity of the remaining film increased to 27% due to preferential degradation of amorphous regions. Furthermore, for all three cutinases, analysis of aqueous soluble degradation products showed that they consist exclusively of terephthalic acid and ethylene glycol.
This paper describes the synthesis, crystal structure, and physicomechanical properties of a biobased polyester prepared from 2,5-furandicarboxylic acid (FDCA) and 1,4-butanediol. ...Melt-polycondensation experiments were conducted by a two-stage polymerization using titanium tetraisopropoxide (TiOiPr4) as a catalyst. Polymerization conditions (catalyst concentration, reaction time and second stage reaction temperature) were varied to optimize poly(butylene-FDCA), PBF, and molecular weight. A series of PBFs with different M w were characterized by DSC, TGA, DMTA, X-ray diffraction and tensile testing. Influence of molecular weight and melting/crystallization enthalpy on PBF material tensile properties was explored. Cold-drawing tensile tests at room temperature for PBF with M w 16K to 27K showed a brittle-to-ductile transition. When M w reaches 38K, the Young modulus of PBF remains above 900 MPa, and the elongation at break increases to above 1000%. The mechanical properties, thermal properties and crystal structures of PBF were similar to petroleum derived poly(butylenes-terephthalate), PBT. Fiber diagrams of uniaxially stretched PBF films were collected, indexed, and the unit cell was determined as triclinic (a = 4.78(3) Å, b = 6.03(5) Å, c = 12.3(1) Å, α = 110.1(2)°, β = 121.1(3)°, γ = 100.6(2)°). A crystal structure was derived from this data and final atomic coordinates are reported. We concluded that there is a close similarity of the PBF structure to PBT α- and β-forms.
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