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Shen Y.-Y.,Xiamen University | Chen X.,Zhejiang Metallurgical Research Institute | Murphy R.W.,CAS Kunming Institute of Zoology | Murphy R.W.,Royal Ontario Museum
PLoS ONE | Year: 2013

In recent years, the number of sequences of diverse species submitted to GenBank has grown explosively and not infrequently the data contain errors. This problem is extensively recognized but not for invalid or incorrectly identified species, sample mixed-up, and contamination. DNA barcoding is a powerful tool for identifying and confirming species and one very important application involves forensics. In this study, we use DNA barcoding to detect erroneous sequences in GenBank by evaluating deep intraspecific and shallow interspecific divergences to discover possible taxonomic problems and other sources of error. We use the mitochondrial DNA gene encoding cytochrome b (Cytb) from turtles to test the utility of barcoding for pinpointing potential errors. This gene is widely used in phylogenetic studies of the speciose group. Intraspecific variation is usually less than 2.0% and in most cases it is less than 1.0%. In comparison, most species differ by more than 10.0% in our dataset. Overlapping intra- and interspecific percentages of variation mainly involve problematic identifications of species and outdated taxonomies. Further, we detect identical problems in Cytb from Insectivora and Chiroptera. Upon applying this strategy to 47,524 mammalian CoxI sequences, we resolve a suite of potentially problematic sequences. Our study reveals that erroneous sequences are not rare in GenBank and that the DNA barcoding can serve to confirm sequencing accuracy and discover problems such as misidentified species, inaccurate taxonomies, contamination, and potential errors in sequencing. © 2013 Shen et al. Source

Yan M.C.,Zhejiang Metallurgical Research Institute
Dong wu xue yan jiu = Zoological research / "Dong wu xue yan jiu" bian ji wei yuan hui bian ji | Year: 2012

Nibea albiflora was immunized by intraperitoneal injection with either Lipopolysaccharide (LPS) or outer membrane protein (OMP) extracted from Vibrio vulnificus or formalin killed Vibrio vulnificus (FKC). The influence of the three antigens on the immunological function of Nibea albiflora was determined at different time points following the injection by testing the agglutinating antibody titers of the serum, lysozyme activity of the serum, phagocytic activity of the blood and the relative survival percentage. The results showed that the three antigens have higher immunogenicity and antigenicity than the control group(injection with sterile saline). The agglutinating antibody titers of the immune challenged groups increased quickly, and were highest on the day 28. The lysozyme activity and phagocytic activity were raised significantly (P<0.01), reaching their top value on day 21, and then the index gradually reduced. The immunological indexes of three immune groups were higher than the control group (P<0.05). The agglutinating antibody titers of the LPS group or the OMP group were lower than the control group, but the relative survival percentage was adverse when challenged with a Vibrio vulnificus infection. The order of relative survival percentage was group LPS>OMP>FKC>Control. Source

Yue X.,CAS Qingdao Institute of Oceanology | Huan P.,CAS Qingdao Institute of Oceanology | Xiao G.,Zhejiang Metallurgical Research Institute | Liu B.,CAS Qingdao Institute of Oceanology
Developmental and Comparative Immunology | Year: 2013

An i-type lysozyme (MmeLys) has been proved to function in immunity of the clam Meretrix meretrix in our previous studies. In this study, the expression patterns of MmeLys mRNA and protein at four chief developmental stages of M. meretrix were analyzed, which was able to provide information about how ontogeny of immunity and, in particular, antibacterial ability occured in the bivalve. The results of real-time PCR and western blot showed that MmeLys expressions were activated in D-veligers and dramatically increased to the highest level in pediveligers. It is proposed that the expression changes at these two stages might be due to the visceral organs changes, which were related to the archenteron formation in D-veligers and the organ-restructuring in pediveligers during metamorphosis. In addition, new methods of whole mount in situ hybridization and whole mount immunofluorescence were applied to identify the MmeLys expression tissues, and these tissues (i.e. hepatopancreas, gill, mantle, mouth, velum and foot) may be involved in the immune function during development of clams. Our study is valuable to a certain extent for exploring the origin of immune functions in clams and provides new methodology for future studies on the immune ontogeny of bivalves. © 2013 Elsevier Ltd. Source

Liu H.,Zhejiang University | Wang X.,Zhejiang University | Liu Y.,Zhejiang University | Dong Z.,Zhejiang Metallurgical Research Institute | And 3 more authors.
Journal of Materials Chemistry A | Year: 2013

Organometallically prepared AlH3 and as-received Al powders were mixed with MgH2 to improve the dehydriding and rehydriding properties of MgH2. Thermal analysis shows that the onset dehydriding temperature of MgH2 is reduced by 55 °C (or 25 °C) when mixed with AlH3 (or Al). The destabilization of MgH2 is attributed to the formation of Mg-Al alloys through the reaction between MgH2 and Al. Isothermal dehydriding measurements demonstrate that AlH3 and Al both improve the dehydriding kinetic of MgH2 to some extent, and it only takes 44 min for MgH2 + AlH3 (5.4 h for MgH2 + Al) to release 60% of the hydrogen of MgH 2 at 300 °C, but 8.6 h are required for as-milled MgH 2. The apparent activation energy for the dehydriding of MgH 2 is reduced from 174.6 kJ mol-1 for as-milled MgH 2 to 154.8 and 138.1 kJ mol-1 for MgH2 mixed with Al and AlH3 respectively; this is responsible for the improvement in the dehydriding kinetics of MgH2. Despite this, AlH3 is better in destabilizing MgH2 than the as-received Al for the fact that Al* formed in situ from the decomposition of AlH 3 is oxide-free on the particle surfaces, which effectively increases the chemical activity of Al*. Furthermore, the brittleness of AlH 3 makes it easier to mix MgH2 with AlH3, which would result in uniform distributions of Mg and Al and shortening of the diffusion length. Concerning the reversibility, at 300 °C and 5 MPa H 2 and MgH2 are fully recovered in the dehydrided MgH 2 + Al, and MgH2 + AlH3 samples after rehydriding for 10 h. The rehydriding kinetic of MgH2 is significantly enhanced for the dehydrided MgH2 + AlH3, but not in the case of the MgH2 + Al. © 2013 The Royal Society of Chemistry. Source

Liu H.,Zhejiang University | Wang X.,Zhejiang University | Liu Y.,Zhejiang University | Dong Z.,Zhejiang Metallurgical Research Institute | And 3 more authors.
Journal of Physical Chemistry C | Year: 2014

In this work, the hydrogen desorption properties of the novel Mg-Al-H hydrogen storage composites prepared by ball-milling the as-received magnesium hydride (MgH2) and the as-prepared aluminum hydride (AlH3) with different molar ratios (1:1, 1:0.5, and 1:0.25) are investigated systematically. Nonisothermal desorption measurements show that more than 7.51 wt % of hydrogen is released from the Mg-Al-H composites when they are heated from room temperature to 500 C. Thermal analysis by differential scanning calorimeter (DSC) and hydrogen desorption spectrum by mass spectrometer (MS-H2) are used synchronously to study the desorption process of the Mg-Al-H. The onset hydrogen desorption temperature of MgH2 in the MgH2 + AlH3 composite is dramatically reduced from 320 C for the pure MgH2 to below 252 C. The DSC/MS-H2 and the X-ray diffraction (XRD) analyses show that the desorption of MgH2 in the Mg-Al-H composite is composed of two steps with the reaction between MgH2 and Al forming Mg17Al12 as the first step and the self-decomposition of the residual MgH2 as the second step. Isothermal desorptions show that the desorption kinetics of the MgH2 in the Mg-Al-H composite is significantly improved. The apparent activation energy for the desorption of MgH2 in the MgH2 + 0.25AlH3 is reduced to 144.6 kJ/mol, which contributes to the improvement in the desorption kinetics of MgH2. The Johnson-Mehl-Avrami (JMA) kinetic studies indicate that the desorption kinetic model of MgH2 in the Mg-Al-H composite is different from the pure MgH2. Concerning the reversibility, under the conditions of 300 C and 5 MPa H2, MgH2 in the Mg-Al-H composite is almost fully recovered after absorption for 5 h while it is partially recovered for the pure MgH2. Among the samples studied, the MgH2 + 0.25AlH 3 composite exhibits the highest reversible hydrogen storage capacity of 6.10 wt % (H/M). © 2013 American Chemical Society. Source

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