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The Songshugang deposit is a large Ta–Nb deposit in South China, with Ta–Nb mineralization associated genetically with the granite and pegmatite. A diversity of quartz from topaz–albite granite, quartz–mica pegmatite, quartz–feldspar pegmatite, and quartz–fluorite pegmatite at Songshugang was studied by CL and LA–ICP–MS in order to constrain enrichment mechanisms of Nb and Ta and to find geochemical indicators of quartz for rare metal deposits. Cathodoluminescence image illuminates a canvas of complexity, the quartz from topaz–albite granite, quartz–mica pegmatite, quartz–feldspar pegmatite, and quartz–fluorite pegmatite, exhibits numerous dark CL streaks, patches, and a series of healed fractures. These textures suggest that the rocks were fractured because of deep crustal pressure, and underwent later hydrothermal metasomatism and quartz filling. The quartz from quartz–fluorite pegmatite present limited patches or fractures but distinct growth bands, indicating that the melt fluid composition during the formation of quartz at this stage varies greatly and is less affected by mechanical fragmentation. The LA–ICP–MS analysis of quartz shows that there is a positive correlation between Al and Li in the quartz from topaz–albite granite, quartz–mica pegmatite, quartz–feldspar pegmatite, to quartz–fluorite pegmatite, indicating that Al mainly enters the quartz lattice through charge compensation substitution mechanism with Li. However, our data deviate from the theoretical Li:Al mass ratio of ~ 1:3.89 in quartz, indicating that there may be competition between H+ and Li in a water-rich magmatic environment. The quartz from topaz–albite granite is enriched in K and Na elements, and the quartz from quartz–fluorite pegmatite is enriched in fluorite with a low Ca content in quartz, further elucidating that these rocks were subjected to hydrothermal metasomatism. From topaz–albitite granite to quartz–fluorite pegmatite, Al, Li and Ge content and Al/Ti, Ge/Ti, Sb/Ti ratios in quartz gradually increased, but Ti content gradually decreased, reflecting the high evolution of magma, which can enrich rare metal elements. Based on the characteristics of quartz CL textures and trace elements in topaz–albite granite, quartz–mica pegmatite, quartz–feldspar pegmatite, and quartz–fluorite pegmatite, combined with the albitization and K-feldspathization of rocks, it is suggested that the Nb–Ta mineralization in Songshugang may be influenced by the combined action of magmatic crystallization differentiation and fluid metasomatism. By comparing the quartz in the Songshugang pluton with the quartz in the granite type and pegmatite type rare metal deposits recognized in the world, the Songshugang pegmatite share similarities with the LCT-type pegmatite. Combined with previous studies, the Ge/Ti > 0.1 and Ti < 10 ppm, as well as Al, Li, Ge, Sb, K, Na contents and Al/Ti, Sb/Ti ratios in quartz have the potential to be a powerful exploration marker for identifying granite-like pegmatitic Nb–Ta deposits in other places. [ABSTRACT FROM AUTHOR]

Purpose: Septate uterus is the most common congenital uterine malformation. This retrospective cohort study compared clinical outcomes and second-look hysteroscopy findings in patients with complete and incomplete septate uteri after septoplasty. Methods: We reviewed the medical records of patients with a septate uterus who underwent hysteroscopic septoplasty and second-look hysteroscopy at the West China Second University Hospital between September 2013 and September 2021. Information regarding pregnancy outcomes was collected through telephone interviews. The independent samples t-test, Mann–Whitney U test, Pearson's chi-square test, and Fisher's exact test were used to explore the differences between the complete and incomplete septate uterus groups. Results: A total of 64 patients were enrolled in this study. There was no significant difference in intrauterine adhesion (IUA) rates (16.7% and 32.1%), pregnancy rates (44.1% and 42.9%), term delivery rates (35.3% and 32.1%), premature delivery rates (2.9% and 0), placenta previa rates (2.9% and 3.6%), placenta implantation/adhesion rates (5.9% and 3.6%), and premature rupture of membranes rates (2.9% and 0) between the complete and the incomplete group after hysteroscopic septoplasty (P > 0.05). Endometrial polyps in the septate uterus were common, with an incidence of 33.3% and 25% in the complete and incomplete groups, respectively (P > 0.05). Conclusion: The pregnancy outcomes of complete and incomplete septate uteri after hysteroscopic septoplasty were similar. There was no statistical difference in IUAs after surgery. Different treatment strategies may not be required for complete or incomplete septate uteri. [ABSTRACT FROM AUTHOR]

Conventional grouting methods present challenges in achieving effective surface rock grouting and avoiding interference with concrete grouting and construction processes. The proposed approach includes reserving rock overburden, controlling grouting pressure and concentration, using a segmented grouting method, and selecting appropriate materials to develop a key method for consolidation grouting. This method not only overcomes the problems associated with the conventional consolidation grouting method but also effectively protects the thin layer of breccia lava in the Baihetan Dam foundation and solves the problem of unloading and relaxation of columnar jointed basalt caused by exposed consolidation grouting. The results show that the post grouting inspection hole permeability qualification rate is 99.3%, with the proportion of high-speed measuring points of various rock types ranging from 91.8% to 93.3%, and the proportion of low-speed measuring points ranging from 2.0% to 2.9%. The drop rate of the grout take of sequence I and sequence II is between 30%–60%, except for some dam sections. These results indicate that the proposed method for consolidation grouting meets the design requirements. The findings have significant implications for the design and construction of consolidation grouting in similar projects. [ABSTRACT FROM AUTHOR]

Bats are reservoirs for multiple coronaviruses (CoVs). However, the phylogenetic diversity and transmission of global bat-borne CoVs remain poorly understood. Here, we performed a Bayesian phylogeographic analysis based on 3,594 bat CoV RdRp gene sequences to study the phylogenetic diversity and transmission of bat-borne CoVs and the underlying driving factors. We found that host-switching events occurred more frequently for α-CoVs than for β-CoVs, and the latter was highly constrained by bat phylogeny. Bat species in the families Molossidae, Rhinolophidae, Miniopteridae, and Vespertilionidae had larger contributions to the cross-species transmission of bat CoVs. Regions of eastern and southern Africa, southern South America, Western Europe, and Southeast Asia were more frequently involved in cross-region transmission events of bat CoVs than other regions. Phylogenetic and geographic distances were the most important factors limiting CoV transmission. Bat taxa and global geographic hotspots associated with bat CoV phylogenetic diversity were identified, and bat species richness, mean annual temperature, global agricultural cropland, and human population density were strongly correlated with the phylogenetic diversity of bat CoVs. These findings provide insight into bat CoV evolution and ecological transmission among bat taxa. The identified hotspots of bat CoV evolution and transmission will guide early warnings of bat-borne CoV zoonotic diseases. [ABSTRACT FROM AUTHOR]

The effect of cooling rate and Nb on the microstructure and hardness variation in microalloying medium-carbon non-quenched and tempered steel simulated in a die forging process was studied by thermal simulation experiments. The full ferrite–pearlite microstructure was formed when the cooling rate was below 0.5 °C/s, and the effect of a cooling rate below 0.5 °C/s was analyzed in detail. The results showed that the cooling rate from 0.1 to 0.3 °C/s had no obvious effect on the hardness of V–Ti steel, with the decrease in V(C, N) precipitation strengthening at the cooling rate of 0.3 °C/s being the main reason. At the cooling rate of 0.1 °C/s, the hardness of V–Ti steel increased by 15 HV with the addition of Nb, and the improvement of precipitation strengthening was the main hardening mechanism. When the cooling rate was increased to 0.3 °C/s, the hardness of V–Ti steel increased by 30 HV with the addition of Nb. The increase in pearlite content, decrease in pearlite interlamellar spacing, and improvement of precipitation strengthening were the main hardening mechanisms. [ABSTRACT FROM AUTHOR]

The hardenability of a carburized Mn-Cr gear steel was calculated and compared by linear model, nonlinear model, analytical function, partial approximation method, 1stOpt, and JMatPro software. Jominy hardness curve and chemical composition data were obtained from a steel plant. An appropriate model was optimized and chosen in accordance with the calculation results. Furthermore, the causes of hardenability fluctuations were clarified. The fluctuation of practical chemical composition was statistically analyzed and calculated by the selected model. The main unstable alloying element was Mn, which had the biggest influence on J15. More significantly, the fluctuations of residual elements Ni and Cu were the root cause of large bandwidth of hardness curve. On this basis, the hardenability bandwidth was controlled to within 4 HRC by composition adjustment. Finally, the shortcomings of the various models were discussed, especially the effect of boron and the micro-alloying element. The result showed that the hardenability was slightly improved after adding 0.02% Nb. The hardenability was reduced when Nb content increased to 0.06%. Boron greatly improved the hardenability, but its effect was unstable. [ABSTRACT FROM AUTHOR]

Nano copper oxide (CuO NP) was added to eight soils to study the effect of aging time of copper on the concentration of diethylenetriaminepentaacetic acid (DTPA)-extracted copper (DTPA-Cu), with bulk copper oxide (CuO BP) and copper nitrate [Cu(NO3)2] used for comparison. Moreover, the effect of soil properties on the dissolution of CuO NP was studied. A dissolution model was used to quantitatively describe the dissolution kinetics of CuO NPs in different soils. The results showed that the concentration of DTPA-Cu decreased with increasing aging time in soils spiked with Cu(NO3)2, while the concentration increased to varying degrees in soils spiked with CuO NPs or CuO BPs. In acidic soils, the equilibrium concentrations of DTPA-Cu were 93.3–98.7 mg·kg−1 for CuO NP treatments, 65.5–94.3 mg·kg−1 for CuO BP treatments, and 81.4–90.0 mg·kg−1 for Cu(NO3)2 treatments, which were greater than those in alkaline soils (43.4–56.9 mg·kg−1, 6.26–8.61 mg·kg−1, and 73.9–80.0 mg·kg−1, respectively). In acidic soils, DTPA-Cu equilibrium concentration ranked the different forms of copper treatments as CuO NPs > Cu(NO3)2 > CuO BPs, while in alkaline soils, the order was Cu(NO3)2 > CuO NPs > CuO BPs. The dissolution rate constants and solubility of CuO NPs were 0.33–6.42 and 37.1–100.1 mg·kg−1, respectively. Pearson correlation analysis indicated that the dissolution parameters of CuO NPs were negatively correlated with soil pH and positively correlated with the contents of organic matter, clay, iron oxides, and aluminum oxides. Further, the dissolution rate constant and solubility of CuO NPs could be well predicted by soil pH and the content of free or amorphous aluminum. Our study identified the main factors controlling the dissolution of CuO NPs in farmland soils and highlighted the higher availability of CuO NPs in acidic soils. [ABSTRACT FROM AUTHOR]

The Baihetan super-high arch dam is constructed under complicated geological conditions, including large-scale columnar jointed basalt (CJB) with closely spaced joints and multiple interlayer and intralayer shear belts at the lower part of dam base, which may increase a risk of seepage in adjacent dam foundations. Therefore, curtain grouting is used to reduce the permeability of dam foundations. Lugeon and grouting field tests and geological exploration were carried out to investigate curtain grouting characteristics of the dam foundation. The findings were as follows: (1) the permeability coefficient of the first type of CJB and breccia lava without unloading is 2 × 10−5 ~ 5 × 10−5 cm/s; that of the second type of CJB without unloading is 2.5 × 10−5 ~ 5 × 10−5 cm/s; and that of the unloaded third type of massive basalt is 1 × 10−5 ~ 3 × 10−5 cm/s. (2) The rock core shows that the slurry caused repeated splitting of the rock mass and widened the cracks of the rock mass, which resulted in plastic deformation of the rock mass. The P ~ Q curve of the five-point Lugeon test shows that the curve shape is turbulent and that the maximum Lugeon value appears at the highest pressure. (3) The phenomenon of low-permeability conditions with a large grout take can be frequently observed. The proportion of the hole stages with a water permeability less than 1 LU and grout take greater than 50 kg/m ranges from 12.5 to 37.5%. The proportion of holes with permeability greater than 10 Lu and grout take greater than 50 kg/m is 0 to 12.5%. The findings from this case study can provide a reference for engineering construction. [ABSTRACT FROM AUTHOR]

Located in the northeastern Hunan Province of South China, the Taolin Pb-Zn deposit is one of many metallic deposits structurally controlled by extensional faults in the central segment of the Jiangnan Orogen. The deposit occurs in a tectonic breccia zone between the Mufushan pluton and the Neoproterozoic Lengjiaxi Group. Field and microscopic observations reveal that the hydrothermal ore-forming processes at Taolin can be divided into five stages, from early to late: (1) coarse-grained quartz, (2) quartz + fluorite + chlorite + claybank sphalerite (Sp1) + galena + chalcopyrite, (3) quartz + barite + pale-yellow sphalerite (Sp2) + galena + chalcopyrite, (4) quartz ± chalcopyrite, and (5) fine-grained quartz, in which the stages 2 and 3 are regarded as the main Pb-Zn-forming events. LA-ICP-MS analyses show that Sp1 has higher contents of Fe, Mn, Co, In, and Sn, but lower contents of Ge and Sb, relative to the Sp2. Trace element concentrations of the sphalerite suggest a medium-low temperature hydrothermal event dominated in the Taolin deposit and that the ore fluids gradually decreased in the estimated average temperature and became relatively oxidized from stages 2 to 3. The δ18O values of ore fluids calculated from in situ analysis on the stages 2 and 3 quartz suggest the ore fluids are from a mixture of magmatic and meteoric waters. The δ34S values of sulfides/sulfates from stages 2 and 3 mineralization indicate a dominating magmatic affinity for sulfur. Further, lead isotope compositions for the stages 2 and 3 sulfides are similar to those of the Mufushan pluton, indicating that the ore metals may have been derived from the latter. We thus propose that the Taolin deposit precipitated from a medium-low temperature magmatic-hydrothermal system most likely related to the Mufushan pluton. [ABSTRACT FROM AUTHOR]

An aerobic, Gram-stain-negative, motile and rod-shaped bacterial strain, designated as Z1-4T, was isolated from the phycosphere microbiota of marine dinoflagellate Alexandrium minutum that produces paralytic shellfish poisoning toxins. Phylogenetic analysis based on 16S rRNA gene sequences showed that the new isolate belongs to the genus Mesorhizobium, and it was closely related to Mesorhizobium waimense LMG 28228T and Mesorhizobium amorphae LMG 18977T with both 16S rRNA gene sequence similarities of 97.3%. The values of average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH) relatedness between strain Z1-4T and its relatives are both well below the thresholds used for the delineation of a new species. A genome-based phylogenetic tree constructed by up-to-date bacterial core gene set (UBCG) indicates that strain Z1-4T forms an independent branch within the genus Mesorhizobium. The respiratory quinone of strain Z1-4T was Q-10. The major fatty acids were similar to other members of the genus Mesorhizobium containing the summed feature 8, C16:0, C19:0cycloω8c, C17:0 and summed feature 3. The polar lipids are phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, an unidentified aminophospholipid, five glycolipids and seven unknown polar lipids. The DNA G + C content was determined to be 62.1 mol % based on its genomic sequence. Combined evidences based on the genotypic, chemotaxonomic and phenotypic characteristics clearly indicates that strain Z1-4T represents a novel species of the genus Mesorhizobium, for which the name Mesorhizobium alexandrii sp. nov. is proposed. The type strain is Z1-4T (= KCTC 72512T = CCTCC AB 2019101T). [ABSTRACT FROM AUTHOR]

Repeated cycles of post-remission high-dose cytarabine (Ara-C) have been suggested to improve survival in core binding factor (CBF) acute myeloid leukaemia (AML). High-dose Ara-C used for induction regimens has also been reported to be associated with increased treatment-related mortality (TRM). Few data are available about intermediate-dose Ara-C serving as induction therapy. The aim of our study was to compare the tolerance and outcomes of standard- and intermediate-dose levels of Ara-C as induction in CBF AML and to analyse the clinical heterogeneity of the two AML entities under these induction settings. We retrospectively investigated the outcomes in adults with CBF AML induced with regimens based on standard-dose Ara-C at 100 to 200 mg/m2 or intermediate-dose Ara-C at 1,000 mg/m2. In total, 152 patients with t(8; 21) and 54 patients with inv(16) AML were administered an induction regimen containing anthracyclines plus either standard- or intermediate-dose Ara-C. After a single course of induction, the complete remission (CR) rate in the inv(16) cohort was 52/52 (100%), higher than the 127/147 (86.4%) in the t(8; 21) cohort (P = 0.005). Intermediate-dose Ara-C (HR = 9.931 [2.135–46.188], P = 0.003) and negative KITmut (HR = 0.304 [0.106–0.874], P = 0.027) independently produced an increased CR rate in the t(8; 21) cohort. Positive CD19 expression (HR = 0.133 [0.045–0.387], P = 0.000) and sex (male) (HR = 0.238 [0.085–0.667], P = 0.006) were associated with superior leukaemia-free survival (LFS) in the t(8; 21) cohort independently of KITmut status or the induction regimen. We conclude that intermediate-dose Ara-C is superior to standard-dose Ara-C for induction of remission in t(8; 21) AML, and CD19 status and sex independently confer prognostic significance for LFS. The KITmut status alone does not have an independent effect on survival in t(8; 21) AML. More intensive induction therapy is unnecessary in inv(16) AML. [ABSTRACT FROM AUTHOR]

Neurological diseases have a close relationship to excessive reactive oxygen species (ROS). Neuroglobin (Ngb), an intrinsic protective factor, protected cells from hypoxic/ischemic injury. In the present, we reported a novel neuroprotective manganese porphyrin reconstituted metal protein, Mn-TAT PTD-Ngb, consisting of a HIV Tat protein transduction domain sequence (TAT PTD) attached to the N-terminal of apo-Ngb. Mn-TAT PTD-Ngb had a stronger ROS scavenging ability than that of TAT PTD-Ngb, and reduced intracellular ROS production and restored the function of the mitochondria and inhibited the mitochondria-dependent apoptosis. Besides, Mn-TAT PTD-Ngb activated the phosphoinositide-3 kinase (PI3K)/Akt signaling pathway, which up-regulated the expression of nuclear factor E2-related factor 2 (Nrf2), Heme oxygenase-1 (HO-1), superoxide dismutase (SOD), catalase (CAT). The results showed that the redox chemistry of Mn-TAT PTD-Ngb and redox regulation of multiple signaling pathways attenuated the oxidative injury. [ABSTRACT FROM AUTHOR]

The Baihetan super-high arch dam is the largest hydropower station in the world under construction. Columnar jointed basalt (CJB) is widely distributed at the Baihetan dam foundation, and the many closely spaced joints pose potential risks on the unloading quality of the foundation surface. In this study, typical unloading cracking and relaxation features of CJB based on field survey and the acoustic wave test are revealed during foundation excavation. Considering the large-scale joints in category-I CJB, an equivalent continuum constitutive model was proposed for describing anisotropic deformation and the unloading relaxation modes and the mechanism of columnar joints are further analysed. Both monitoring and numerical results show that: 1) the unloading behaviours include shallow relaxation of columnar joints and combined rebound deformation of columnar joints and shear belts; 2) the relaxation range of columnar joints mainly occurs at the shallow foundation surface with the maximum depth of 3~4 m, and the relaxation degree is obviously exaggerated owing to the sliding of shear belts; 3) the unloading relaxation mode at the shallow foundation mainly belongs to rebound deformation and relaxation of oral joints. The tensile failure occurs in steep joints, and both tensile and shear failure occur in gentle joints. The proposed model can be applied to effectively simulate the unloading relaxation processes of dam foundation excavation. [ABSTRACT FROM AUTHOR]

Columnar jointed basalt (CJB), characterized by a hexagonal joint network, poses a great challenge for geotechnical designs due to its time-dependent propensity to deformation and damage. In this paper, the geometrical structure and failure modes of CJB exposed on a dam foundation is presented. The study was conducted during the unloading excavation of the Baihetan dam, China, aiming to provide a more in-depth understanding of the CJB damage mechanism. A systematic field test for the columnar jointed rock mass was also carried out on the dam foundation using ultrasonic P wave measurements. It was found that the excavation damage zone of the CJB not only showed time-dependent damage both in depth and degree but also showed spatially inhomogeneous distribution of the damage degree. Sequential regression analysis further demonstrated the time-dependent behavior of the CJB. Successive observations using digital borehole cameras in the field showed that the unloading damage mechanism of the Baihetan CJB was mainly related to the time-dependent opening of the initially closed joints. Several reinforcing methods for improving the stability of the damaged CJB, including the injection of liquid cement and the installation of the prestressed rock bolts, are discussed. [ABSTRACT FROM AUTHOR]

The Baihetan super-high arch dam is constructed under complicated geological conditions, including large-scale columnar jointed basalt with closely spaced joints and multiple interlayer and intralayer shear belts at the lower part of dam base. Due to large excavation depth and scale at the dam base, unloading deformation and relaxation of columnar jointed basalt and shear belts were revealed by field investigation, in situ testing, monitoring, and numerical simulations. It was found that the relaxation depth of columnar jointed basalt was related to geostress, rock mass quality, and gently dipping shear belts. The time effect of unloading relaxation is also obvious in the columnar jointed basalt. In terms of unloading deformation control, comprehensive reinforcement measures and proper construction sequence at the dam base were proposed, including reservation of a 5-m-thick rock mass layer as the protective layer, consolidation grouting on the protective layer, preinstallation of mortar anchors through consolidation grouting hole, excavation of protective layers with controlled blasting in small benches, timely anchorage by prestressed cables upon exposure of foundation surface, and additional consolidation grouting for shallow foundation rock mass under concrete cover weight. With the comprehensive reinforcement measures at the dam base, the relaxation depth of columnar jointed basalt was small and shear deformation of shear belts was effectively controlled. Thus, the proposed reinforcement measures were proven to be proper and effective, which could meet the requirements of dam base and provide some reference for similar hydropower projects. [ABSTRACT FROM AUTHOR]

Ischemia-reperfusion (I/R)-induced spinal cord injury can cause apoptotic damage and subsequently act as a blood-spinal cord barrier damage. MicroRNAs (miRNAs) contributed to the process of I/R injury by regulating their target mRNAs. miR-199a-5p is involved in brain and heart I/R injury; however, its function in the spinal cord is not yet completely clarified. In this study, we investigated the role of miR-199a-5p on spinal cord I/R via the endothelin-converting enzyme 1, especially the apoptosis pathway. In the current study, the rat spinal cord I/R injury model was established, and the Basso Beattie Bresnahan scoring, Evans blue staining, HE staining, and TUNEL assay were used to assess the I/R-induced spinal cord injury. The differentially expressed miRNAs were screened using microarray. miR-199a-5p was selected by unsupervised hierarchical clustering analysis. The dual-luciferase reporter assay was used for detecting the regulatory effects of miR-199a-5p on ECE1. In addition, neuron expression was detected by immunostaining assay, while the expressions of p-ERK, ERK, p-JNK, JNK, caspase-9, Bcl-2, and ECE1 were evaluated by Western blot. The results indicated the successful establishment of the I/R-induced spinal cord injury model; the I/R induced the damage to the lower limb motor. Furthermore, 18 differentially expressed miRNAs were detected in the I/R group compared to the sham group, and miR-199a-5p protected the rat spinal cord injury after I/R. Moreover, miR-199a-5p negatively regulated ECE1, and silencing the ECE1 gene also protected the rat spinal cord injury after I/R. miR-199a-5p or silencing of ECE1 also regulated the expressions of caspase-9, Bcl-2, p-JNK, p-ERK, and ECE1 in rat spinal cord injury after I/R. Therefore, we demonstrated that miR-199a-5p might protect the spinal cord against I/R-induced injury by negatively regulating the ECE1, which could aid in developing new therapeutic strategies for I/R-induced spinal cord injury. [ABSTRACT FROM AUTHOR]

The austenite growth behavior of non-quenched and tempered steels (casted by continuous casting and molding casting processes) was studied. The austenite grain size of steel B casted by continuous casting process is smaller than that of steel A casted by molding casting process at the same heating parameters. The abnormal austenite growth temperature of the steels A and B are 950 °C and 1000 °C, respectively. Based on the results, the models for the austenite grain growth below and above the abnormal austenite growth temperature of the investigated steels were established. The dispersedly distributed fine particles MnS in steel B is the key factor refining the austenite grain by pinning the migration of austenite grain boundary. The elongated inclusions MnS are ineffective in preventing the austenite grain growth at high heating temperature. For the non-quenched and tempered steel, the continuous casting process should be adopted and the inclusion MnS should be elliptical, smaller in size and distributed uniformly in order to refine the final microstructure and also improve the mechanical properties. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is an obligate intracellular apicomplexan parasite, and can infect warmblooded animals and humans all over the world. In the past years, ROP family genes encoding particular proteins of T. gondii had made a great contribution to toxoplasmosis. In this study, we used multiple bioinformatics approaches to predict the physical and chemical characteristics, transmembrane domain, epitope, and topological structure of the rhoptry protein 48 (ROP48). The results indicated that ROP48 protein was mainly located in the membrane and had several positive linear-B cell epitopes and Th-cell epitopes, which suggested that ROP48 is a potential DNA vaccine candidate against toxoplasmosis. Then the PCR product amplified from the ROP48 cDNA was inserted into a pEASY-T1 vector to build a recombinant cloning plasmid. After sequencing, ROP48 was subcloned into a eukaryotic expression plasmid pEGFP-C1 to obtain pEGFP-C1-ROP48 (pROP48). After identification by PCR and restriction enzyme digestion, the recombinant plasmid pROP48 was transfected into HEK 293-T cell and identified by RT-PCR. The results showed that the eukaryotic expression plasmid pROP48 was constructed and transfected to the cells of HEK 293-T successfully. Western blotting showed that the expressed proteins can be recognized by anti-STAg mouse sera. [ABSTRACT FROM AUTHOR]

Oil-water relative permeability curve constitutes important basic data in reservoir engineering. Given the influence of dead volume on experimental apparatus, the actual oil-water relative permeability curve cannot be obtained when the unsteady-state method is adopted to measure oil-water relative permeability. In this paper, on the basis of the analysis of the influence of dead volume on oil-water relative permeability, we summarize the conventional methods used to overcome dead volume and then propose the use of relationship theory between resistivity and water saturation to calibrate the oil-water relative permeability curve. This method mainly aims at to measure the resistance values at both ends of the core by using a resistance-measuring instrument. Meantime, the Archie formula is used to calibrate the relational expression of core resistivity and water saturation based on the steady-state experimental method. Therefore, the core of the actual cumulative oil production and the average water saturation can be calculated, and then oil-water relative permeability can be accurately computed without the influence of dead volume. By comparing the oil displacement process of dead volume calculated through two different methods (probability subtraction and resistivity methods), the crude oil in dead volume is found to be displaced at the beginning of the displacement. The oil-water relative permeability curve corrected through resistivity method can eliminate the influence of dead volume and iterative error in calculation, and is consistent with the law of the actual development of oilfield, which has certain theoretical and practical application values. [ABSTRACT FROM AUTHOR]

The Internet is a typical complex network, whose traffic load is controlled by the inter-domain routing system. Due to the co-location of data plane and control plane of Border Gateway Protocol, the survivability of inter-domain routing system is sensitive to severe congestion. Therefore, an initial outage may lead to a cascade of failures in the Internet. But the cascading failures on links are able to be automatically restored when the congestion is mitigated. In this paper, we propose a model - CAFEIN for characterizing this special process. Based on CAFEIN, we assess the difference of impact under intentional attacks and random breakdowns; identify the worst affected part of the Internet; and study the propagation of cascading failures. Through simulations, we find that the cascading failures bring a great deal of added burden to the routing system. However, the cascading effect is amplified globally when the relative capacity of links is very low. Moreover, the difference of impact between intentional attack and random breakdown is not as prominent as previous research due to the unique automatic-restoration process. [ABSTRACT FROM AUTHOR]

Isolated NE-SW stretching the Helan Mountain massif, separating the temperate grassland of the Ordos plateau from the Tenggeli Desert, is a key position of studying the glacier development in west China as well as the coupling conditions of climate change with tectonic uplift. The glacial landforms and deposits including cirques, peaks, knife-edge ridges, lateral moraines, and terminal moraines distribute above 2800 m a.s.l. in the middle part of the Helan Mountain. This distribution indicates that here was once glaciated during the late Quaternary. Morphology features show a clear sequence of landscape forming events took place throughout the Helan Mountain. Laboratory optically stimulated luminescence (OSL) and accelerator mass spectrometry radiocarbon dating (AMS C) results indicate a late history of glacial advance. Late Pleistocene glaciers in the middle part of the Helan Mountain advanced to near their positions at least four times, and the glacial sequences can be assigned as the middle stage of last glacial cycle (MIS3b, 43.2±4.0 ka), last glacial maximum (LGM, ∼18 ka), late glacial (12.0±1.1 ka) and neo-glacial (3.4±0.3 ka) respectively. Adopting equilibrium line altitude ∼2980 m of last glacial maximum and the modern theoretical snowline altitude ∼4724 m as the maximum amplitudes, and the standard marine isotope curve (MIS) as the glacial equilibrium line change since the Gonghe Movement (150 ka), the relationship between the mountain altitude and glacier development is discussed herein. Compared with other environmental indexes such as the loess-paleosol and ice core, conclusions are made that glacier advances in the Helan Mountain during the late Quaternary obviously depended on the coupled control of tectonic uplift of mountain with the climate condition. It is at last glaciation that the mountain reached the altitude above snowline and coupled with the glacial climate. The glacial advances occurred in the early and middle stages of last glacial cycle after the Gonghe Movement. [ABSTRACT FROM AUTHOR]