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The Wulian complex is located on the northern margin of the Sulu orogenic belt, and was formed by collision between the North China Craton (NCC) to the north and South China Craton (SCC) to the south. It consists of the metasedimentary Wulian Group, gneissic granite and meta-diorite. The U–Pb analyses for the detrital zircons from the Wulian Group exhibit one predominant age population of 2600–2400 Ma with a peak at c. 2.5 Ga and several secondary age populations of > 3000, 3000–2800, 2800–2600, 2200–2000, 1900–1800, 1500–1300 and 1250–950 Ma; some metamorphic zircons have metamorphic ages of c. 2.7, 2.55–2.45, 2.1–2.0 and 1.95–1.80 Ga, which are consistent with magmatic-metamorphic events in the SCC. Additionally, the Wulian Group was intruded by the gneissic granite and meta-diorite at c. 0.76 Ga, attributed to Neoproterozoic syn-rifting bimodal magmatic activity in the SCC and derived from partial melting of Archaean continental crust and depleted mantle, respectively. The Wulian Group therefore has tectonic affinity to the SCC and was mainly sourced from the SCC. The detrital zircons have positive and negative ϵHf(t) values, indicating that their source rocks were derived from reworking of both ancient and juvenile crustal rocks. The major early Precambrian crustal growth took place during c. 3.4–2.5 Ga with a dominant peak at 2.96 Ga and several secondary peaks at 3.27, 2.74 and 2.52 Ga. The two oldest zircons with ages of 3307 and 3347 Ma record the recycling of ancient continental crust (> 3.35 Ga) and crustal growth prior to c. 3.95 Ga in the SCC.
To introduce some questionnaires related to family environment such as FAD-GFS (The General Functioning Scale of the MacMaster Family Activity Device), SLE (stressful life events), FSQ (Family Stresses Questionnaire), FLQ (Family Life Questionnaire), EFQ (Everyday Feelings Questionnaire) and evaluate their validity and reliability.
Using cross-sectional design. The general questionnaire, FAD-GFS, SLE, FSQ, FLQ, EFQ were used to collect information about family environment from 504 parents of only children FACESII-CV and Index of General Affect were used as scale of criteria related.
The reliability and validity of FAD-GFS, SLE, FSQ, FLQ, EFQ is: Cronbach coefficient were 0.695 to 0.749; re-test reliability were 0.712 to 0.901; The scores of the scale in those questionnaires were correlated with each factor significantly and the coefficient of correlation is more than those between each factor of those scales. The correlation between the scores of FSQ, EFQ and the scores of Index of General Affect was-0.192, 0.539; The correlation between the scores of FAD-GFS, FLQ the score of total and three factor differently and the scores of family cohesion scores (FACESII-CV) was -0.423, 0.237, 0.514, 0.302, 0.210.
FAD-GFS, SLE, FSQ, FLQ, EFQ has good reliability and validity, in line with requirements of psychometric and is useful as a tool to evaluate the family environment.
Laves phase plays a positive role in improving the strength of high-entropy alloys (HEAs); Nb and Ti elements have potential to promote Laves phase formation in some HEAs. For improving the strength of the face-centered cubic (FCC) CoCrFeMnNi HEA, a series of (CoCrFeMnNi)100−xNbx (atomic ratio: x = 0, 4, 8, 12, 16) and (CoCrFeMnNi)100−xTix (atomic ratio: x = 0, 2, 4, 6, 8, 12) HEAs were prepared by melting. The effects of Nb and Ti on the microstructure evolution and compressive properties of the CoCrFeMnNi HEAs were investigated. For (CoCrFeMnNi)100−xNbx HEAs, the second-phase (Laves and σ phase) volume fraction increased from 0 to 42%. The yield strength also increased gradually from 202 to 1010 MPa. However, the fracture strain decreased from 60% (no fracture) to 12% with increasing Nb content. For (CoCrFeMnNi)100−xTix HEAs, the yield strength increased from 202 to 1322 MPa. The Laves phase volume fraction also increased from 0 to 27%. However, the fracture strain decreased from 60% (no fracture) to 7.5% with increasing Ti content. Addition of Nb and Ti has a good effect on improving the strength of FCC CoCrFeMnNi HEA.
This paper presents new LA-ICP-MS zircon U–Pb chronology, whole-rock geochemical and zircon Hf isotopic data for the felsic lavas of the Huili Group from the southwestern Yangtze Block. LA-ICP-MS zircon U–Pb dating shows that these rocks were emplaced in Late Mesoproterozoic time (∼1028 to 1019 Ma). Relative to typical I-type and S-type granitoids, all the samples are characterized by low Sr and Eu, and high high-field-strength element contents, high TFeO/MgO, enriched rare earth element compositions and negative Eu anomalies, indicating that they share the geochemical signatures of A-type granitoid. They can be further divided into two groups: Group I and Group II. Group I are A1-type felsic rocks and were produced by fractional crystallization of alkaline basaltic magmas. The Group II felsic lavas belong to the A2-type and were derived by partial melting of a crustal source with mixing of mantle-derived magmas. Both Group I and Group II felsic lavas may erupt in a continental back-arc setting. The coexistence of A1- and A2-type rocks in the southwestern Yangtze Block suggests that they can occur in the same tectonic setting.
Northeastern China is a region of high tick abundance, multiple tick-borne pathogens and likely human infections. The spectrum of diseases caused by tick-borne pathogens has not been objectively evaluated in this region for clinical management and for comparison with other regions globally where tick-transmitted diseases are common. Based on clinical symptoms, PCR, indirect immunofluorescent assay and (or) blood smear, we identified and described tick-borne diseases from patients with recent tick bite seen at Mudanjiang Forestry Central Hospital. From May 2010 to September 2011, 42% (75/180) of patients were diagnosed with a specific tick-borne disease, including Lyme borreliosis, tick-borne encephalitis, human granulocytic anaplasmosis, human babesiosis and spotted fever group rickettsiosis. When we compared clinical and laboratory features to identify factors that might discriminate tick-transmitted infections from those lacking that evidence, we revealed that erythema migrans and neurological manifestations were statistically significantly differently presented between those with and without documented aetiologies (P < 0.001, P = 0.003). Twelve patients (6.7%, 12/180) were co-infected with two tick-borne pathogens. We demonstrated the poor ability of clinicians to identify the specific tick-borne disease. In addition, it is necessary to develop specific laboratory assays for optimal diagnosis of tick-borne diseases.
The phase stability, equilibrium lattice parameters, mechanical properties, and chemical bonding of M2B and M2B0.75C0.25 (M = Fe, Cr, W, Mo, Mn) were studied using first-principles calculations within density functional theory. These compounds are thermodynamic stability structures, and the M2B0.75C0.25 stability is worse than that of M2B. The equilibrium lattice parameters are consistent with other available experimental and theoretical data. Stress–strain and Voigt–Reuss–Hill approximations were used to estimate the elastic constants (Cij) and moduli (B, G, E), respectively. The bulk modulus and the ductility increased by adding an appropriate amount of C to the M2B. The compound hardness was studied using a theoretical method based on the work of Tian. The chemical bonding of these compounds was estimated using the Mulliken population analysis and density of states, and the results indicate that the bonding behaviors of these compounds are combinations of metallic and covalent bonds.
The influence of heat treatment (homogenization) on the microstructure, mechanical behavior, and soft magnetic properties of a face-centered cubic (fcc)-based high-entropy alloy (HEA), Fe29Co28Ni29Cu7Ti7, fabricated by casting, was investigated in detail. The as-cast Fe29Co28Ni29Cu7Ti7 HEA was composed of a primary fcc phase containing coherent dispersed L12 nanoprecipitates and trace amounts of a needle-like phase. The tensile yield strength (σ0.2), ultimate strength, and total elongation of the as-cast alloy are 917 MPa, 1060 MPa, and 1.8%, respectively. Following homogenization, the alloy having a single fcc phase shows a decrease of ∼ 55% in yield strength and a decrease of ∼ 36% in ultimate strength; however, the total elongation is increased from 1.8 to 52%. Saturation magnetization (Msat) is decreased from 111.54 to 110.34 Am2/kg, by contrast, coercivity (Hc) is increased from 266.65 to 966.89 A/m. The dissolution of precipitates and grain growth are mainly responsible for the changes in magnetic properties and mechanical behavior.
The BeiDou navigation satellite system (BDS) has been providing a regional service in the Asia–Pacific area since 27 December 2012, and a new Inclined Geosynchronous Satellite Orbit (IGSO) satellite IGSO-6 joined the 14-satellite constellation in operation on 29 March 2016. In this paper, the signal and positioning performance of IGSO-6 are assessed. Compared with other IGSOs, the carrier-to-noise-density ratios of IGSO-6 show comparable performance for the B3 signal and a lower power level for the B2 signal, while the B1 signal is more powerful and has the lowest noise and multipath errors. The satellite-induced code bias of IGSO-6 was investigated and indicates that IGSO-6 has similar characteristics to other IGSOs. The different inter-frequency bias variations among IGSOs with daily periodicity are demonstrated. The BDS positioning performances with IGSO-6 were investigated in Single Point Positioning (SPP) and Precise Point Positioning (PPP) modes at the 95% confidence level. For SPP, there was an improvement of about 4·9% and 3·6% in the horizontal and vertical components, respectively. The convergence time was improved by about 18·3% and 17·8% in the horizontal and vertical components for positioning accuracy to be better than 50 cm, respectively.
Since 2010, Jankowski’s Bunting Emberiza jankowskii has been listed as ‘Endangered’ on the IUCN Red List of Threatened Species. However, because no comprehensive surveys had been conducted, it was not known whether undiscovered populations existed elsewhere, so the population status of the species could not be assessed accurately. The aim of this study was to assess the breeding distribution and population size of Jankowski’s Bunting in China. Fifty sites in Inner Mongolia, and Jilin, Heilongjiang, Liaoning and Hebei Provinces were surveyed to locate suitable habitat and breeding populations of Jankowski’s Bunting. The surveyed sites included historical breeding distribution areas, wintering sites, and regions adjacent to historical breeding distribution areas. We confirmed that Jankowski’s Bunting has disappeared from most of its former breeding distributions, with the exceptions of Dagang, Xiergen and Tumiji. Additionally, 13 new breeding sites were discovered in Inner Mongolia. All currently known populations breed in Mongolian steppe-vegetation zones, with shrubs dominated by the natural Siberian apricot Prunus sibirica, indicating that this type of habitat is crucial for the survival of the species. Based on remote sensing, the suitable breeding habitat for Jankowski’s Bunting is estimated to be approximately 280 km2. The population size of Jankowski’s Bunting could range between 9,800 and 12,500 individuals, which is much higher than the numbers estimated in previous reports that were based on partial surveys. The suitable habitat remaining in Inner Mongolia would highly benefit from the implementation of the National Key Public Forest Protection Project. The population size of Jankowski’s Bunting is larger than previously estimated, but it is still threatened by habitat degradation and fragmentation, and our survey results reinforce the need for more research. The status of Jankowski’s Bunting in China still meets the IUCN criteria B2ab for an ‘Endangered’ species.
We examined the in vitro developmental competence of parthenogenetic activation (PA) oocytes activated by an electric pulse (EP) and treated with various concentrations of AZD5438 for 4 h. Treatment with 10 µM AZD5438 for 4 h significantly improved the blastocyst formation rate of PA oocytes in comparison with 0, 20, or 50 µM AZD5438 treatment (46.4% vs. 34.5%, 32.3%, and 24.0%, respectively; P < 0.05). The blastocyst formation rate was higher in the group treated with AZD5438 for 4 h than in the groups treated with AZD5438 for 2 or 6 h (42.8% vs. 38.6% and 37.2%, respectively; P > 0.05). Furthermore, 66.67% of blastocysts derived from these AZD5438-treated PA oocytes had a diploid karyotype. The blastocyst formation rate of PA and somatic cell nuclear transfer (SCNT) embryos was similar between oocytes activated by an EP and treated with 2 mM 6-dimethylaminopurine for 4 h and those activated by an EP and treated with 10 µM AZD5438 for 4 h (11.11% vs. 13.40%, P > 0.05). In addition, the level of maturation-promoting factor (MPF) was significantly decreased in oocytes activated by an EP and treated with 10 µM AZD5438 for 4 h. Finally, the mRNA expression levels of apoptosis-related genes (Bax and Bcl-2) and pluripotency-related genes (Oct4, Nanog, and Sox2) were checked by RT-PCR; however, there were no differences between the AZD5438-treated and non-treated control groups. Our results demonstrate that porcine oocyte activation via an EP in combination with AZD5438 treatment can lead to a high blastocyst formation rate in PA and SCNT experiments.
The hydrogenation behavior of Ti–44Al–6Nb (at.%) alloy was studied at temperature range of 1373–1693 K, and the effect of hydrogen on hot deformability was tested on Gleeble-1500D thermo-simulation machine. It is found that the lnCH increases linearly with 1/T, and hydrogen content increases with increasing of hydrogen time and flow rate logarithmically. The positive heat of solution of hydrogen denotes that hydrogen absorption in TiAl alloys is an endothermic reaction. The results also show that hydrogen promotes the lamellar colony size and lamellar spacing because that hydrogen can promote the diffusion of elements. There is more residual B2 phase in the hydrogenated alloy revealing that hydrogen stabilizes the B2 phase during hydrogenation. The nanohardness and elastic modulus of the alloy are decreased from 4.4 and 213.5 GPa to 4.2 and 199.8 GPa after hydrogenation with 0.033 wt% H. Thermal simulation results show that the peak stress is decreased by 30% after hydrogenation with 0.033 wt% H which corresponds to decreasing the deformation temperature by about 50 K. This is attributed to hydrogen-promoted dynamic recrystallization and dislocation movement.
In this paper, bymeans of a new recursive algorithm of non-tensor-product-typed divided differences, bivariate polynomial interpolation schemes are constructed over nonrectangular meshes firstly, which is converted into the study of scattered data interpolation. And the schemes are different as the number of scattered data is odd and even, respectively. Secondly, the corresponding error estimation is worked out, and an equivalence is obtained between high-order non-tensor-product-typed divided differences and high-order partial derivatives in the case of odd and even interpolating nodes, respectively. Thirdly, several numerical examples illustrate the recursive algorithms valid for the non-tensor-product-typed interpolating polynomials, and disclose that these polynomials change as the order of the interpolating nodes, although the node collection is invariant. Finally, from the aspect of computational complexity, the operation count with the bivariate polynomials presented is smaller than that with radial basis functions.
Early reperfusion therapy in the treatment of ST segment elevation myocardial infarction (STEMI) patients can improve outcomes. Silent myocardial infarction is associated with poor prognosis, but little is known about its effect on treatment delays. We aimed to characterize STEMI patients presenting without complaints of pain to the emergency departments (EDs) in Singapore.
Retrospective data were requested from the Singapore Myocardial Infarction Registry (SMIR), a national level registry in Singapore. Painless STEMI was defined as the absence of pain (chest, back, shoulder, jaw, and epigastric pain) during ED presentation. The primary outcome was door-to-balloon (D2B) time, defined as the earliest time a patient arrived in the ED to balloon inflation. Secondary outcomes were 1-month and 1-year mortality and occurrence of adverse events.
From January 2010 to December 2012, the SMIR collected 6412 cases; 10.9% of patients presented without any pain. These patients were older (median age =75 v. 58 years old), more likely to be females (39.9% v. 16.1%), Chinese (74.9% v. 62.7%), obese (median body mass index [BMI] =24.5 v. 22.1), and with history of hypertension (71.1% v. 54.6%), diabetes mellitus (48.6% v. 37.0%), and acute myocardial infarction (20.0% v. 12.3%). They had a longer median D2B (80.5 v. 63 minutes, p<0.001) and a higher occurrence of 30-day (38.4% v. 5.7%) and 1-year mortality rates (47.3% v. 8.5%).
A small proportion of STEMI patients presented without any pain to the ED. They tended to have a higher D2B and risks of mortality. Targeted effort is required to improve diagnostic and treatment efficiency in this group.
Malaria remains one of the most devastating diseases. Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection resulting in high mortality and morbidity worldwide. Analysis of precise mechanisms of CM in humans is difficult for ethical reasons and animal models of CM have been employed to study malaria pathogenesis. Here, we describe a new experimental cerebral malaria (ECM) model with Plasmodium berghei ANKA infection in KunMing (KM) mice. KM mice developed ECM after blood-stage or sporozoites infection, and the development of ECM in KM mice has a dose-dependent relationship with sporozoites inoculums. Histopathological findings revealed important features associated with ECM, including accumulation of mononuclear cells and red blood cells in brain microvascular, and brain parenchymal haemorrhages. Blood–brain barrier (BBB) examination showed that BBB disruption was present in infected KM mice when displaying clinical signs of CM. In vivo bioluminescent imaging experiment indicated that parasitized red blood cells accumulated in most vital organs including heart, lung, spleen, kidney, liver and brain. The levels of inflammatory cytokines interferon-gamma, tumour necrosis factor-alpha, interleukin (IL)-17, IL-12, IL-6 and IL-10 were all remarkably increased in KM mice infected with P. berghei ANKA. This study indicates that P. berghei ANKA infection in KM mice can be used as ECM model to extend further research on genetic, pharmacological and vaccine studies of CM.
The yaw attitudes of Global Positioning System (GPS) satellites are critical to both satellite antenna phase centres and the phase wind-up corrections. However, the nominal yaw attitude of GPS satellites can barely be maintained during eclipse seasons. Thus, several yaw attitude models have been developed by the International GNSS Service Analysis Centres (IGS ACs) to avoid positioning degradation caused by non-nominal yaw attitudes. Based on the analysis of the strategy of each AC, the modelled yaw attitude is compared with the nominal one, and the residuals of Precise Point Positioning (PPP) are investigated to evaluate the influence of non-nominal attitudes with over one year of observable data collected from 15 IGS stations. The results suggest that non-nominal attitudes of BLOCK II/IIA satellites have the largest impact of about 20–30 cm, and their positioning accuracy can be improved by 20%−30% with the corresponding yaw attitude model. Similar results have also been demonstrated with BLOCK IIR and BLOCK IIF satellites. Furthermore, compared with the strategy of directly deleting the data for the eclipsing seasons, PPP with the yaw-attitude model achieves better results by about 30% when the satellite geometry is relatively poor.
Whiteflies have distinct nymphal stages: their first stage is mobile, whereas the later immature stages are sessile. The developmental and structural changes of antennae and antennal sensilla in whiteflies during these stages have rarely been investigated. This paper describes the morphology of antennae and antennal sensilla in four nymphal stages of Aleurodicus dispersus based on scanning electron microscopy. There were significant differences found in shape and length of the antennae, and differences in type, number, morphological structure and distributional pattern of antennal sensilla in the four nymphal stages of A. dispersus. We found two types of sensilla on the antennae of first-instar nymph, three types on the third-instar nymphal antennae, four types on the second-instar and seven types on the fourth-instar nymphal antennae. Sensilla trichoidea (ST) and elevated sensilla placodea were found on the antennae of each nymphal stage, sensilla chaetica only occurred on the antennae of fourth-instar nymph. Sensilla furcatea occurred on the antennae of second- and third-instar nymphs, and sensilla basiconica were found on the antennae of second- and fourth-instar nymphs. In addition, there were sensilla campaniform and sensilla coeloconica found only on the antennae of fourth-instar nymph, whereas the ST of fourth-instar nymphs included sensilla trichoidea 1 and sensilla trichoidea 2. The possible functions of antennal sensilla are discussed. Our results contribute to a better understanding of the development of the olfactory system of whitefly nymphal stages, and provide a basis for further exploration of chemical communication mechanisms between whiteflies and host plants.
We present a high precision frequency determination method for digitized NMR FID signals. The method employs high precision numerical integration rather than simple summation as in many other techniques. With no independent knowledge of the other parameters of a NMR FID signal (phase ф, amplitude A, and transverse relaxation time T2) this method can determine the signal frequency f0 with a precision of if the observation time T ≫ T2. The method is especially convenient when the detailed shape of the observed FT NMR spectrum is not well defined. When T2 is +∞ and the signal becomes pure sinusoidal, the precision of the method is which is one order more precise than the ±1 count error induced precision of a typical frequency counter. Analysis of this method shows that the integration reduces the noise by bandwidth narrowing as in a lock-in amplifier, and no extra signal filters are needed. For a pure sinusoidal signal we find from numerical simulations that the noise-induced error in this method reaches the Cramer-Rao Lower Band (CRLB) on frequency determination. For the damped sinusoidal case of most interest, the noise-induced error is found to be within a factor of 2 of CRLB when the measurement time T is 2 or 3 times larger than T2. We discuss possible improvements for the precision of this method.