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Echinococcus granulosus sensu stricto (s.s.), Echinococcus multilocularis and Echinococcus canadensis are the common causes of human echinococcosis in China. An accurate species identification tool for human echinococcosis is needed as the treatments and prognosis are different among species. The present work demonstrates a method for the simultaneous detection of these three Echinococcus species based on multiplex polymerase chain reaction (mPCR). Specific primers of this mPCR were designed based on the mitochondrial genes and determined by extensive tests. The method can successfully detect either separated or mixed target species, and generate expected amplicons of distinct size for each species. Sensitivity of the method was tested by serially diluted DNA, showing a detection threshold as less as 0.32 pg for both E. granulosus s.s. and E. canadensis, and 1.6 pg for E. multilocularis. Specificity assessed against 18 other parasites was found to be 100% except weakly cross-react with E. shiquicus. The assay was additionally applied to 69 echinococcosis patients and 38 healthy persons, confirming the high reliability of the method. Thus, the mPCR described here has high application potential for clinical identification purposes, and can further provide a useful tool for evaluation of serology and imaging method.
A varactor-based fully reconfigurable microstrip bandpass-to-bandpass-with-embedded-stopband filter is presented in this paper. This filter offers wide center frequency and bandwidth tuning flexibility under both bandpass mode and bandpass-with-embedded-stopband mode. The entire tuning ability is based on multiple mode resonator theory and external quality factor tuning structure for bandpass mode and the introduction of transmission zeros (TZs) for bandpass-with-embedded-stopband mode. Under the bandpass mode, the center frequency tuning range is 0.96–1.45 GHz and the bandwidth can be tuned from 0.09 to 1.41 GHz with a fixed center frequency at 1.22 GHz. Under bandpass-with-embedded-stopband mode, the center frequency and bandwidth can be tuned from 0.94 to 1.61 GHz and 0.2–0.33 GHz, respectively. Good agreements are shown between simulated and measured results.
Heavy metal contamination in the paddy soils of China is a serious concern because of its health risk through transfer in food chains. A field experiment was conducted in 2014–2015 to investigate the long-term effects of different biochar amendments on cadmium (Cd) and arsenic (As) immobilisation in a contaminated paddy field in southern China. Two types of biochar, a rice-straw-derived biochar (RB) and a coconut-by-product-derived biochar (CB), were amended separately to determine their impacts on rice yield and their efficacy in reducing Cd and As in rice. The two-year field experiment showed that biochar amendments significantly improved the rice yields and that CB is superior to RB, especially in the first growth season. Using a large amount of biochar amendment (22.5tha–1) significantly increased soil pH and total organic carbon, and concomitantly decreased the Cd content in rice grains over the four growth seasons, regardless of biochar type and application rate. Arsenic levels in rice were similar to the control, and results from this study suggest that there was a sustainable effect of biochar on Cd sequestration in soil and reduction of Cd accumulation in rice for at least two years. Biochar amendment in soil could be considered as a sustainable, reliable and cost-effective option to remediate heavy metal contamination in paddy fields for long periods.
In the field of modernised Global Navigation Satellite System (GNSS) signal design, several Dual-frequency Constant Envelope Multiplexing (DCEM) methods have been recently proposed. However, the existing DCEM methods, such as Alternative Binary Offset Carrier (AltBOC), generalised AltBOC and Asymmetric Constant Envelope Binary Offset Carrier (ACE-BOC), are only applied in some special cases. In this paper, we present a unified DCEM design framework for GNSS signals. The existing DCEM methods can be unified in this framework. First, the signal components at two carrier frequencies are combined into two single-frequency constant envelope signals. Then, the linear sum of dual-frequency signals with non-constant envelopes is obtained. Finally, the linear sum is converted into the corresponding DCEM signal by solving an optimisation problem. The proposed design framework has no strict constraints on the number, power ratio and phase relationship of the signal components. Moreover, some special design cases under this framework are also analysed in detail. The analytical results show that the proposed design method can reach higher multiplexing efficiency compared with the existing methods. Based on the proposed method, we suggest a scheme to multiplex the BeiDou regional signals and global signals at the B2 frequency. The simulation results of correlation functions and Power Spectrum Density (PSD) verify the correctness and effectiveness of the proposed design method.
In this paper, a triple-wideband bandpass filter (BPF) with controllable bandwidths based on two multi-mode stub-loaded resonators (MMSLRs) and a triple-mode resonator is presented. The MMSLR is loaded with two identical folded open-ended stubs and a T-shaped stub. Each passband of the tri-band BPF is formed by four resonant modes, which provide sufficient bandwidths to meet various application requirement. By adjusting the lengths of open-ended stubs, three passband bandwidths can be controlled individually. The center frequencies of the triple-wideband BPF are allocated at 2.7, 3.67, and 5.44 GHz, with the 3 dB fractional bandwidths (FBWs) of 20.1, 14.7, and 26.3%. Among the three passbands, the highest one covers the 5 G WiFi band (5.15–5.85 GHz). The measured results of the proposed filter exhibit excellent agreement with simulated results.
A new genus and species of the Elcanidae (Orthoptera, Elcanoidea), Cascadelcana virginiana n. gen. n. sp., is described based on a forewing specimen from the Upper Triassic (Norian) Cow Branch Formation in the Solite Quarry Lagerstätte near the North Carolina-Virginia boundary, USA. It is distinguished from other elcanid species by its RP+MA1 with six branches, M with two branches before stem MA1 fused with RP, and short CuA almost vertical against the posterior margin. This fossil represents the earliest definitive record of the family Elcanidae and the first orthopteran described from the Triassic of North America. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analyses show that the veins and a pterostigma-like structure on the wing of C. virginiana n. gen. n. sp. are preserved as carbonaceous compressions. The presence of a pterostigma-like structure in elcanids indicates that they may have evolved a particular flight mechanism distinct from those of other orthopterans.
An Al–3% B master alloy has been subjected to equal channel angular pressing (ECAP). The grain refining performance and fading resistance of an Al–3% B master alloy on a commercial purity Al (CPA) have been evaluated. The effect of the number of ECAP passes on the size and the distribution of the AlB2 particles, the grain size of CPA ingots with and without adding the Al–3% B master alloy subjected to ECAP have been investigated. The mean size of AlB2 particles was significantly reduced from ∼34 to ∼12 μm after four ECAP passes. Fine blocky AlB2 particles were uniformly distributed in the Al matrix. It has been revealed that when it was inoculated by the Al–B master alloy subjected to ECAP, the grain size of α-Al was decreased from ∼1200 to ∼180 μm after four ECAP passes, beyond that, the grain size tends to be saturated. It has been proved that grain refinement efficiency and fading resistance of the Al–3% B master alloy subjected to ECAP in CPA ingots was enhanced.
Five orthopteran specimens from the uppermost Middle–lowermost Upper Jurassic of Daohugou, Inner Mongolia, China are described and attributed to the genus Sigmaboilus Fang, Zhang & Wang, 2007 (Prophalangopsidae); and a new species, S. calophlebius sp. nov., is established herein. The diagnostic characters for Sigmaboilus are revised and a key to species of Sigmaboilus, based on male forewings, is provided. Intraspecific variation in forewings of this genus is also discussed.
This study aimed to investigate the effects of dietary live yeast (LY) supplementation on growth, intestinal permeability and immunological parameters of piglets challenged with enterotoxigenic Escherichia coli K88 (ETEC). Piglets weaned at 21 d were allocated into three treatments with six pens and six piglets per pen, receiving the control diet (CON), diets supplemented with antibiotics plus zinc oxide (ANT–ZnO) and LY (Saccharomyces cerevisiae strain CNCM I-4407), respectively, for a period of 2 weeks. On day 8, thirty-six piglets were selected as control without ETEC (CON), CON–ETEC, ANT–ZnO–ETEC and LY–ETEC groups challenged with ETEC until day 10 for sample collections. Piglets fed ANT–ZnO diet had the highest average daily gain and average daily feed intake (P<0·05) during the 1st week, but ADG of piglets fed the ANT–ZnO diet was similar as piglets fed LY diet during the second week. Piglets with LY–ETEC or ANT–ZnO–ETEC had markedly lower diarrhoea score (P<0·05) than piglets with CON–ETEC during the 24 h after ETEC challenge. Relative to piglets with CON, the counts of E. coli, urinary ratio of lactulose to mannitol, plasma IL-6 concentration, mRNA abundances of innate immunity-related genes in ileum and mesenteric lymph node tissues were increased (P<0·05), whereas the villous height of jejunum and relative protein expression of ileum claudin-1 were decreased (P<0·05) in piglets with CON–ETEC; however, these parameters did not markedly change in piglets with LY–ETEC or ANT–ZnO–ETEC. In summary, dietary LY supplementation could alleviate the severity of diarrhoea in piglets with ETEC, which may be associated with the improved permeability, innate immunity and bacterial profile.
More than 200 molecular clouds were newly found distributed beyond the Outer arm in the extreme outer Galaxy (EOG) region by MWISP. Those MCs roughly following the HI′s distribution well delineate the outermost spiral structure (the Outer Scutum-Centaurus arm) and warp of our Galaxy. Besides, those MCs show different σv-Radius relation and exhibit higher value of αvir than MCs in the inner Galaxy.
Previous studies have investigated the association between dietary inflammatory potential and the development of cancer. For breast cancer the results have been equivocal. The present study aimed to investigate whether higher Dietary Inflammatory IndexTM (DII) scores were associated with increased risk of breast cancer among Chinese women. A total of 867 cases and 824 controls were recruited into the present case–control study from September 2011 to February 2016. DII scores were computed based on baseline dietary intake assessed by a validated 81-item FFQ. The OR and 95 % CI were assessed by multivariable logistic regression after adjusting for various potential confounders. DII scores in this study ranged from −5·87 (most anti-inflammatory score) to +5·71 (most proinflammatory score). A higher DII score was associated with a higher breast cancer risk (adjusted ORquartile 4 v. 1 2·28; 95 % CI 1·71, 3·03; adjusted ORcontinuous 1·40; 95 %CI 1·25, 1·39). In stratified analyses, positive associations also were observed except for underweight women or women with either oestrogen receptor+ or progesterone receptor+ status (but not both). Results from this study indicated that higher DII scores, corresponding to more proinflammatory diets, were positively associated with breast cancer risk among Chinese women.
Two stone tablets in the Wangye Museum, Shenzhen, contain a bilingual Sogdian and Chinese epitaph for a Sogdian merchant and his wife, who lived in the northern Chinese city of Ye 鄴 in the late sixth century ce. The two texts are published here for the first time and accompanied by a detailed commentary on philological and historical points of interest.
The BiOBr/Ag3PO4 composites were fabricated by a facile in situ deposition of Ag3PO4 nanoparticles on the BiOBr microsheets and analyzed by X-ray diffraction, scanning electron microscope, high resolution transmission electron microscope, X-ray photoelectron spectroscopy, UV–vis diffuse reflectance absorption spectra, Fourier transform infrared, Raman, photoluminescence (PL), and photoelectrochemical techniques. The photocatalytic performances of as-prepared samples were investigated and compared through degradation of Rhodamine B (RhB) solution. The results suggested that 30 wt% amount of BiOBr in the composites possessed the highest photocatalytic activity. The remarkably improved photocatalytic performances of BiOBr/Ag3PO4 composites could be ascribed to the efficient separation of electron–hole pairs, due to suitable energy band potentials between BiOBr and Ag3PO4. Furthermore, the photoelectrochemical and PL tests verified the separation and transfer efficiency of charges was promoted.
Climate change impacts on and is impacted by areas such as development, economy, security and energy. The concept of climate security encompasses a number of different phenomena and has increasingly been conceptualized in terms of fragility and resilience. Climate change can threaten people's survival and wellbeing (Barnett 2003: 7) and act as conflict multiplier (Adger and Puhin 2014). It can put pressure on economic, social and political systems as well as development processes. Failure to manage these pressures can increase the instability of states and societies. Climate security policy aims to strengthen the resilience of states and societies. This includes climate change mitigation and adaptation efforts, development and humanitarian aid programs as well as peace-building and conflict prevention (Mabey et al. 2011: 12–16; Rüttinger et al. 2015).
Climate security is closely interrelated with energy security. Burning fossil fuels to produce energy is the leading source of greenhouse gas (GHG) emissions, which cause climate change. In turn, climate change affects the security of energy supply (Umbach 2012). Climate change and energy security policies can contradict or reinforce each other. When measures to ensure energy security include a shift toward an increasing share of renewable sources, both policy areas are synergetic. When a move toward more domestic energy generation includes increasing use of fossil fuels, the increase of energy security is detrimental to climate policy goals.
Both the EU and China are large GHG emitters, which makes them major contributors to climate change. In 2013, China emitted 29 percent and the EU 11 percent of total global carbon dioxide emissions. The United States accounted for a 15 percent share (Oliver et al. 2014: 4). China and the EU also share a large degree of energy import dependence. In 2013, the EU imported 53.2 percent of its gross energy consumption (European Commission 2014a; Eurostat 2015) while China's import dependence also is above 50 percent.
Although both the EU and China are fully aware of the threats of climate change to human wellbeing and hold concerns of energy security, their perceptions of and responses to climate and energy security diverge. This fosters both cooperation and persisting divergences at global and bilateral levels.
The following section elaborates EU and Chinese perceptions of climate and energy security, followed by a discussion of the two players’ responses to perceived security concerns over the past two decades.
Flavonoids may play an important role in the protective effects of vegetables, fruits and tea against colorectal cancer. However, associations between flavonoids and colorectal cancer risk are inconsistent, and a few studies have evaluated the effect of flavonoids from different dietary sources separately. This study aimed to evaluate associations of flavonoids intake from different dietary sources with colorectal cancer risk in a Chinese population. From July 2010 to December 2015, 1632 eligible colorectal cancer cases and 1632 frequency-matched controls (age and sex) completed in-person interviews. A validated FFQ was used to estimate dietary flavonoids intake. Multivariate logistical regression models were used to calculate the OR and 95 % CI of colorectal cancer risk after adjusting for various confounders. No significant association was found between total flavonoids and colorectal cancer risk, with an adjusted OR of 1·06 (95 % CI 0·85, 1·32) comparing the highest with the lowest quartile. Anthocyanidins, flavanones and flavones intakes from total diet were found to be inversely associated with colorectal cancer risk. Compared with the lowest quartile, the adjusted OR for the highest quartile were 0·80 (95 % CI 0·64, 1·00) for anthocyanidins, 0·28 (95 % CI 0·22, 0·36) for flavanones and 0·54 (95 % CI 0·43, 0·67) for flavones. All subclasses of flavonoids from vegetables and fruits were inversely associated with colorectal cancer. However, no significant association was found between tea flavonoids and colorectal cancer risk. These data indicate that specific flavonoids, specifically flavonoids from vegetables and fruits, may be linked with the reduced risk of colorectal cancer.
In this paper, the recent studies of laboratory astrophysics with strong magnetic fields in China have been reviewed. On the Shenguang-II laser facility of the National Laboratory on High-Power Lasers and Physics, a laser-driven strong magnetic field up to 200 T has been achieved. The experiment was performed to model the interaction of solar wind with dayside magnetosphere. Also the low beta plasma magnetic reconnection (MR) has been studied. Theoretically, the model has been developed to deal with the atomic structures and processes in strong magnetic field. Also the study of shock wave generation in the magnetized counter-streaming plasmas is introduced.
Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case–control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (Pinteraction=0·029) and BHMT rs3733890 (Pinteraction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.
We report new field observations, zircon U–Pb ages and geochemical data for the discrete members of the Zhaheba ophiolite complex in northeastern Junggar of the Central Asian Orogenic Belt (CAOB) with the aim to understand the accretion process of the eastern Junggar terrane. The zircon age data reveal that the cumulates of the Zhaheba ophiolite crystallized at ~485 Ma while the volcanic sequences erupted at ~400 Ma. Thus, the volcanic sequences are not members of the Zhaheba ophiolite. Chromian spinels from the serpentinite have comparable elemental compositions to those of spinels from MORB-type ophiolites. Similarly, the rift affinity of clinopyroxene and positive zircon εHf(t) (13–20) and mantle δ18O (+5.37‰) values of the cumulates imply that the cumulates crystallized from primitive magmas derived from a depleted mantle source. Elemental and Nd isotopic compositions indicate that the basalts in the Zhaheba area were derived from partial melting of a mantle wedge metasomatized by adakitic melts and/or subduction-related fluids. The data presented in this contribution, together with previous studies, indicate that the Zhaheba–Almantai and Kelameili ophiolites were MORB-type, which implies that there were at least two mid-ocean ridges during Ordovician to early Devonian times in the Junggar Ocean. In the earlier stage, intra-oceanic subduction led to the formation of the intra-oceanic arc, and then the Kelameili ophiolite accreted to an intra-oceanic accretionary wedge. In the later stage, the Zhaheba–Almantai ophiolite accreted to the accretionary wedge along the southern margin of the Iritish suture zone during the roll-back of the subduction zone from north to south.
Rapid solidification of Al30Si70 alloy was studied via electromagnetic levitation technique. The solidification kinetics and the morphology of the solidification front of the Si phase were analyzed in situ by using a high-speed video camera and subsequent microstructural analysis of as-solidified samples. It shows that solidification of the sample always starts from one point. After that, nucleation continues to proceed at the interface front during growth. The morphology of primary Si transforms from faceted wafer to nonfaceted equiaxed grain and the grain size decreases with increase of undercooling. At small undercooling, the growth velocity of primary Si decreases with time and the floated Si wafers have a trend to agglomerate, while at large undercooling, the nucleation rate decreases with time, which are explained by the fact that silicon content, undercooling and density at the solid–liquid interface change with time in solidification. Finally, the nucleation rate and growth velocity were discussed in combination of classical theory.