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The 2Cr13/316L multilayered composite plates were fabricated by hot rolling with recycle heating step. The effect of rolling reductions on microstructure and properties was investigated. The 2Cr13 layer consists of martensite and lath ferrite, but the middle layer has less ferrite than both sides. The content and grains of ferrite increase with the increase of the reduction and number of reheating, which leads to a decrease in the hardness of the 2Cr13 layer. The hardness of the 2Cr13 layer is determined by the volume ratio of martensite and ferrite. Tensile strength of the specimens with the rolling reduction of 72% and 82% reached 815.8 MPa and 763.4 MPa, while elongations were 20% and 20.8%, respectively. With the increase of the rolling reduction, the fracture mode also changed from cleavage fracture to dimple fracture. There were no cracks and delamination when the 2Cr13/316L composite plate bent to 130° and 180°, which indicated better interfacial bonding.
P systems with active membranes are a class of bioinspired computing models, where the rules are used in the non-deterministic maximally parallel manner. In this paper, first, a new variant of timed P systems with active membranes is proposed, where the application of rules can be regulated by promoters with only two polarizations. Next, we prove that any Turing computable set of numbers can be generated by such a P system in the time-free way. Moreover, we construct a uniform solution to the
problem in the framework of such recognizer timed P systems in polynomial time, and the feasibility and effectiveness of the proposed system is demonstrated by an instance. Compared with the existing methods, the P systems constructed in our work require fewer necessary resources and RS-steps, which show that the solution is effective to NP-complete problem.
Several epidemiological studies have investigated that Na or K intakes might be associated with the metabolic syndrome (MetS). However, little evidence has evaluated the association between Na:K ratio and the MetS. In this study, we assessed the association between the dietary Na:K ratio and the MetS. The cross-sectional study was conducted among adults aged 18 years and older in Nanjing, using a multi-stage random sampling method, which resulted in a sample size of 1993 participants. Dietary Na and K intakes were assessed by 3 consecutive days of dietary recollection combined with condiments weighing method. Health-related data were obtained by standardised questionnaires, as well as physical examinations and laboratory assessments. The prevalence rate of the MetS was 36·5 % (728/1993). After adjusting for various lifestyle and dietary factors of the MetS, participants in the highest quartile of dietary Na:K ratio were at a higher risk of developing MetS (OR=1·602; 95 % CI 1·090, 2·353) compared with those in the lowest quartile. Each 1-sd increase in dietary Na:K ratio was associated with a higher risk of prevalent MetS (OR=1·166; 95 % CI: 1·018, 1·336). Among the components of the MetS, dietary Na:K ratio was positively associated with high blood pressure (quartile 3 v. quartile 1: OR=1·656; 95 % CI 1·228, 2·256) and hypertriacylglycerolaemia (quartile 4 v. quartile1: OR=1·305; 95 % CI 1·029, 1·655) in multivariate analysis. These results revealed that higher dietary Na:K ratio significantly increased the risk of the MetS in Chinese adults. Further studies are needed to verify this association.
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.
To investigate the effects of heat stress on broiler metabolism, we assigned 144 broilers to normal control (NC), heat stress (HS) or pair-fed (PF) groups and then monitored the effects using growth performance, carcass characteristics, biochemical assays and GC-MS-based metabolomics. The up-regulation of cloacal temperature confirmed that our experiment was successful in inducing chronic heat stress. The average daily gain and average daily feed intake of the HS group were significantly lower than those of the NC group, by 28·76 and 18·42 %, respectively (P<0·001), whereas the feed:gain ratio was significantly higher, by 14·49 % (P=0·003), and heat stress also increased leg proportion (P=0·027) and intramuscular fat proportion (P<0·001) and decreased breast proportion (P=0·009). When comparing the HS and NC groups and HS and PF groups, our metabolomics approach identified seventy-eight and thirty-four metabolites, respectively, with significantly different levels (variable importance in the projection values >1 and P<0·05). The greater feed:gain ratio of the HS group was significantly positively correlated with the leg, abdominal fat, subcutaneous fat and intramuscular fat proportions and levels of some free amino acids (proline, l-cysteine, methionine and threonine) but was negatively correlated with breast proportion and levels of some NEFA (stearic acid, arachidonic acid, palmitic acid and oleic acid). These findings indicated that the heat-stressed broilers were in negative energy balance and unable to effectively mobilise fat, thereby resulting in protein decomposition, which subsequently affected growth performance and carcass characteristics.
Auto-alignment is a basic technique for high-power laser systems. Special techniques have been developed for laser systems because of their differing structures. This paper describes a new sensor for auto-alignment in a laser system, which can also serve as a reference in certain applications. The authors prove that all of the beam transfer information (position and pointing) can theoretically be monitored and recorded by the sensor. Furthermore, auto-alignment with a single lens sensor is demonstrated on a simple beam line, and the results indicate that effective auto-alignment is achieved.
In the light curves of some solar-type stars, both rotational modulation (caused by corotating bright or dark magnetic features) and flare phenomena can be seen simultaneously. Based on these light curve observations, the relation between stellar magnetic feature activity (reflected by the rotational modulation component of the light curves) and flare activity can be investigated. Here, we analyze the light curve data of a flare-abundant solar-type star, KIC 6034120, observed with Kepler space telescope, and describe magnetic feature activity property by fluctuation range of light curves and flare activity property by time occupation ratio of flares. Distinct phase difference between long-term magnetic feature activity and flare activity is found for this star, which indicates that the source regions of stellar flares (e.g., starspots) on this star do not dominate the rotational modulation of light curves, yet they might be related to a same stellar dynamo process.
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.
Large volumes of data collected by the Automatic Identification System (AIS) provide opportunities for studying both single vessel motion behaviours and collective mobility patterns on the sea. Understanding these behaviours or patterns is of great importance to maritime situational awareness applications. In this paper, we leveraged AIS trajectories to discover vessel spatio-temporal co-occurrence patterns, which distinguish vessel behaviours simultaneously in terms of space, time and other dimensions (such as ship type, speed, width etc.). To this end, available AIS data were processed to generate spatio-temporal matrices and spatio-temporal tensors (i.e., multidimensional arrays). We then imposed a sparse bilinear decomposition on the matrices and a sparse multi-linear decomposition on the tensors. Experimental results on a real-world dataset demonstrated the effectiveness of this methodology, with which we show the existence of connection among regions, time, and vessel attributes.
Palaeoproterozic metasedimentary rocks, also referred to as khondalites, characterized by Al-rich minerals, are extensively exposed in the nucleus of the Yangtze craton, South China block. Samples of garnet–sillimanite gneiss in the khondalite suite were collected from the Kongling complex for Nd isotopic and elemental geochemical study. These rocks are characterized by variable SiO2 contents ranging from 35.71 to 58.07 wt%, and have low CaO (0.45–0.84 wt%) but high Al2O3 (18.56–29.04 wt%), Cr (174–334 ppm) and Ni (42.5–153 ppm) contents. They have high CIW (Chemical Index of Weathering) values (90.4–94.7), indicating intense chemical weathering of the source material. The samples display light rare earth elements (LREE) enrichment with negative Eu anomalies (Eu/Eu*=0.40–0.68), and have flat heavy rare earth elements (HREE) patterns. The high contents of transition elements (e.g. Cr, Ni, Sc, V) and moderately radiogenic Nd isotopic compositions suggest that the paragneisses might be those of first-cycle erosion products of predominantly mafic rocks mixing with small amounts of felsic moderately evolved Archaean crustal source. Geochemical and Nd isotopic compositions reveal that at least some of the protoliths of Kongling khondalite were sourced from local pre-existing mafic igneous rocks in a continental arc tectonic setting. Combined with documented zircon U–Pb geochronological data, we propose that the Palaeoproterozoic high-pressure granulite-facies metamorphism, rapid weathering, erosion and deposition of the khondalites in the interior of the Yangtze craton might be related to a Palaeoproterozoic collisional orogenic event during 2.1–1.9 Ga, consistent with the worldwide contemporary orogeny, implying that the Yangtze craton may have been an important component of the Palaeoprotorozoic Columbia supercontinent.
Brief cognitive–behavioural therapy (CBT) is an emerging treatment for
schizophrenia in community settings; however, further trials are needed,
especially in non-Western countries.
To test the effects of brief CBT for Chinese patients with schizophrenia
in the community (trial registration: ChiCTR-TRC-13003709).
A total of 220 patients with schizophrenia from four districts of Beijing
were randomly assigned to either brief CBT plus treatment as usual (TAU)
or TAU alone. Patients were assessed at baseline, post-treatment and at
6- and 12-month follow-ups by raters masked to group allocation.
At the post-treatment assessment and the 12-month follow-up, patients who
received brief CBT showed greater improvement in overall symptoms,
general psychopathology, insight and social functioning. In total, 37.3%
of those in the brief CBT plus TAU group experienced a clinically
significant response, compared with only 19.1% of those in the TAU alone
group (P = 0.003).
Brief CBT has a positive effect on Chinese patients with schizophrenia in
The objective of this study was to determine the protective effect of glutamate (Glu) in Cu-induced oxidative injury in fish intestine in vivo and enterocytes in vitro. The results indicated that exposure to 6 mg/l Cu for 72 h induced the production of reactive oxygen species, thereby increasing protein oxidation and lipid peroxidation in enterocytes of grass carp in vitro. Cells exposed to Cu alone resulted in a significant increase in lactate dehydrogenase release, which is accompanied by depletions of antioxidants, including total superoxide dismutase (T-SOD), glutathione S-transferase (GST), glutathione reductase (GR), anti-superoxide anion (ASA), anti-hydroxy radical (AHR) activities and GSH content. Pre-treatment with Glu remarkably prevented the toxic effects of Cu on the T-SOD, GST, GR, AHR, and ASA activities and GSH content in enterocytes. However, Cu induced an adaptive increase in the activities of catalase and glutathione peroxidase (GPx). Glu supplementation further increased GPx activity in enterocytes. Interestingly, the experiment in vivo showed that Glu pre-supplementation significantly elevated SOD, GPx, GST, GR, ASA and AHR activities, as well as GSH content. Further results showed that pre-treatment with Glu could alleviate Cu-induced oxidative injury by elevating antioxidant enzyme activities through regulating the expression of NF-E2-related nuclear factor 2 (Nrf2) mRNA. Together, these results indicated that Glu could attenuate Cu-induced cellular oxidative damage in fish intestine, likely mediated through Nrf2 signalling pathways regulating mRNA expressions of antioxidant enzyme genes and synthesis of GSH.
Thermoluminescence (TL) and radioluminescence (RL) are reported over the temperature range 25–673 K from MgSiO4:Tb and MgSiO4:Eu. The dominant signals arise from the transitions within the Rare Earth (RE) dopants, with limited intensity from intrinsic or host defect sites. The Tb and Eu ions distort the lattice and alter the stability of the TL sites and the peak TL temperature scales with the Tb and Eu ion size. The larger Eu ions stabilize the trapped charges more than for the Tb, and so the Eu TL peak temperatures are ∼20% higher. There are further size effects linked to the TL driven by the volume of the upper state orbitals of the rare earth transitions. For Eu the temperatures of the TL peaks are wavelength dependent since higher excited states couple to distant traps via more extensive orbits. The same pattern of peak temperature data is encoded in RL during heating. The data imply that there are sites in which the rare earth and charge stabilizing defects are closely associated within the host lattice, and the stability of the entire complex is linked to the lattice distortions from inclusions of impurities.
Faultline configurations in top management teams are of vital importance in predicting firm outcomes. Grounded in faultline theory, we hypothesise the positive effects of faultlines through the dual routes of coordination and information processing under conditions of various subgroup configuration types. Second-hand data from publicly traded Chinese information technology firms are used to test our hypotheses. The results demonstrate that TMT faultline strength is positively related to a firm’s short-term performance only when both the number and the balance of subgroups are high and is positively related to a firm’s innovation activities only when the number of subgroups is high and the balance of subgroups is low. This study contributes to faultline theory by enriching the connotation of faultlines with the configurational perspective and advancing the debate on the effects of team faultlines as we reveal the benefits of TMT faultlines.
On 13 December 2012, Chang'e-2 completed a successful flyby of the near-Earth asteroid 4179 Toutatis at a closest distance of 770 meters from the asteroid's surface. The observations show that Toutatis has an irregular surface and its shape resembles a ginger-root of a smaller lobe (head) and a larger lobe (body). Such bilobate shape is indicative of a contact binary origin for Toutatis. In addition, the high-resolution images better than 3 meters provide a number of new discoveries about this asteroid, such as an 800-meter depression at the end of the large lobe, a sharply perpendicular silhouette near the neck region, boulders, indicating that Toutatis is probably a rubble-pile asteroid. Chang'e-2 observations have significantly revealed new insights into the geological features and the formation and evolution of this asteroid. In final, we brief the future Chinese asteroid mission concept.
Boulders are ubiquitous on the surfaces of asteroids and their spatial and size distributions provide information for the geological evolution and collisional history of parent bodies. We identify more than 200 boulders on near-Earth asteroid 4179 Toutatis based on images obtained by Chang'e-2 flyby. The cumulative boulder size frequency distribution (SFD) gives a power-index of −4.4 ± 0.1, which is clearly steeper than those of boulders on Itokawa and Eros, indicating much high degree of fragmentation. Correlation analyses with craters suggest that most boulders cannot solely be produced as products of cratering, but are probably survived fragments from the parent body of Toutatis, accreted after its breakup. Similar to Itokawa, Toutatis probably has a rubble-pile structure, but owns a different preservation state of boulders.
A crucial problem is the risk that a manipulator arm would be damaged by twisting or bending during and after contacting a target satellite. This paper presents a solution to minimize the risk of damage to the arm and thereby enhance contact performance. First, a hand-eye servo controller is proposed as a method for accurately tracking and capturing a target satellite. Next, a motion planning strategy is employed to obtain the best-fit contacting moments. Also, an impedance control law is implemented to increase protection during operation and to ensure more accurate compliance. Finally, to overcome the challenge of verifying algorithms for a space manipulator while on the ground, a novel experimental system with a 6-DOF (degree of freedom) manipulator on a chaser field robot is presented and implemented to capture a target field robot; the proposed methods are then validated using the experimental platform.