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Amphioxus, as the best living proxy to the chordate ancestor, is considered an irreplaceable model organism for evolutionary studies of chordates and deuterostomes. In this study, a high-quality genome of the Beihai amphioxus,Branchiostoma belcheribeihai, wasde novoassembled and annotated. Within four amphioxus genomes, a wide range of gene novelties were identified, revealing new genes that share unexpectedly high similarities with those from non-metazoan species. These gene innovation events have played roles in a range of amphioxus adaptations, including innate immunity responses, adaptation to anaerobic environments, and regulation of calcium balance. The gene novelties related to innate immunity, such as a group of lipoxygenases and a DEAD-box helicase, boosted amphioxus immune responses. The novel genes for alcohol dehydrogenase and ferredoxin could aid in the anaerobic tolerance of amphioxus. A proximally arrayed cluster of EF- hand calcium-binding protein genes were identified to resemble those of bacteria. The copy number of this gene cluster was linearly correlated to the sea salinity of the collection region, suggesting that it may enhance their survival at different calcium concentrations. Collectively, this comprehensive study on gene novelties of amphioxus reveals insights into the early genome evolution of chordates and deuterostomes and provides valuable resources for future research.Significance statementAmphioxus is a slow-evolving model organism for the study of chordate evolution, and while much research has focused on its ortholog evolution, relatively little attention has been paid to its gene innovations. In this study, we assembled and annotated a high-quality genome of the Beihai amphioxus and identified gene novelties across four amphioxus genomes. Many of these new genes resembled those from non-metazoan species, suggesting the possibility of horizontal gene transfer. These gene novelties have been found to enhance amphioxus adaptations, including innate immune responses and anaerobic tolerance. Of particular interest is a cluster of novel EF-hand calcium- binding protein genes located in proximity, which present similarity to bacterial genes. These genes may facilitate adaptation to different calcium concentrations in amphioxus.

By method of TIG, two kinds of welding materials were filled in, under certain welding craft conditions，1Cr18Ni9Ti and 2Cr13 were welded. By OM(ZEISS)、SEM，the microstructure of two kinds of 2Cr13 and 1Cr18Ni9Ti welding joints were observed and analyzed, by electronic universal tensile machine，mechanical properties of welding joints were measured. The results show that 2Cr13 and 1Cr18Ni9Ti welded joints is typical columnar crystal, the microstructure is lath martensite +residual austenite + carbide，the welding joints filled in two kinds of materials， rupture forms are toughness rupture; Elongation and tensile strength of welding joint filled in 308 welding material is better than that filled in H1Cr21Ni10Mn7Mo welding wire.

The traditional response estimation model is based on force-response relationship. According to the transmissibility concept in linear time invariant system, a new response estimation method-transmissibility function (TF) method is provided based on response-response relationship. First, the principle of the method is interpreted in mathematic formula and the restriction condition is presented. Then, an engineering technique called operational conditions combination is presented for calculating the transmissibility function (TF) of vibration responses, and the guideline on how to devise the scheme of working conditions is discussed. Finally, the performance of the developed transmissibility function method is validated by a cylindrical double-shell exciting experiment.

FRF measurements can suffer from various errors. The effect of deterministic errors become more prominent compared to random errors in FRF measurement. Excitation and sensor misalignment is the most common source of deterministic error, so mathematic model is established and the effect on FRF estimation was analyzed for senor and excitation misalignment situations. Finite element model simulation reveals that misalignment error can have the least effect on the dominant FRFs and a stronger effect on lesser FRFs, beside that it also results in the appearance of false peaks in the measured FRFs.

By method of TIG, under certain welding craft conditions, two kinds of welding wire were added,1Cr18Ni9Ti and 2Cr13 steel were welded. By (ZEISS) OM, SEM, the microstructure of two kinds of 2Cr13 and 1Cr18Ni9Ti welding joints were observed and analyzed, by electronic universal tensile machine, mechanical properties of welding joints were measured. The results show that 2Cr13 and 1Cr18Ni9Ti welded joints is typical columnar crystal, the microstructure is lath martensite + residual austenite + carbide; the micro-hardness of two kinds of welding joint changes fluctuantly, it increases firstly and reduces secondly, the value is up to max in welded joint zone. The welding joints filled in two kinds of materials, tensile samples rupture forms are toughness rupture; plasticity and strength of welding joint filled in ER308 welding material is better than that of welding joint filled in H1Cr21Ni10Mn7Mo welding wire. On the contrary, its hardness is lower than that filled in H1Cr21Ni10Mn7Mo welding wire.

By method of TIG, and under certain welding craft conditions,1Cr18Ni9Ti and 2Cr13 were welded. By (ZEISS) OM,SEM,the microstructure of two kinds of 2Cr13 and 1Cr18Ni9Ti welding joints were observed and analyzed, Through seawater immersion test, polarization curves and AC impedance spectroscopy of 1Cr18Ni9Ti and 2Cr13 welding joints were obtained. The results show that 2Cr13 and 1Cr18Ni9Ti welded joints is typical columnar crystal, the microstructure is lath martensite + austenite + carbide; polarization curves and AC impedance spectroscopy show that corrosion resistance of welding joint from strong to weak is: austenite base metal>HAZ near austenite>welded joint>HAZ near martensite>martensite base metal; corrosion resistance of welded joint is between martensite base metal and austenite base metal.

The rupture and deformation of Shaft wall in the vertical topsoil in coal mining, which appears on the common and also is relatively unique phenomenon in China. Today with the increasing of the deep and extra deep Shaft, the destruction of the Shaft wall brings us more difficult task. To solve this basic problem need to figure out the shaft wall rupture mechanism. This paper discusses the current research status of the shaft wall, existence problems and content of the research. We did a lot of engineering investigation and analysis. Focus on the structure design of the wall, the main factors of influence rupture, mechanical characteristics of side wall and etc. Summarizing the shortage that in the study of the shaft wall rupture mechanism, making a supplementary . At the same time, the corresponding relationship between the vertical pressure with the groundwater level, between the groundwater level with vertical additional force. Maximum value of the vertical additional force . The inner link between vertical additional force with vertical pressure, with the depth of surface soil, with the diameter of the mineshaft, the thickness of side wall, the measures for preventing vertical shaft flood. From the five aspects, which reveal the content, analysis the object of study, and show the important significance of research.

Q390 steel owns lots of good mechanical properties, it is used in many fields. By means of Gleeble 1500D thermal simulation machine, high temperature tensile tests were carried out; by OM,SEM, the fracture pattern and the microstructure of different distance from the fracture were watched and analyzed; by means of hardness test, the micro-hardness of different distance from the fracture was measured. The results show that the rupture at different temperature belongs to ductile rupture, with distance increasing from the fracture, the microstructure changes from composition structure of martensite, bainite, residual austenite into base metal structure, the grain size is smaller and smaller. The fracture hardness increases firstly and decreases secondly when tensile temperature increases, it is up to the max when temperature is 1200°C, the value is 395HV; the micro-hardness increases firstly and decreases secondly with distance increasing from the fracture, the hardness is the max when distance is 10mm,8mm,10mm at 800°C,1000°C,1200°C tensile temperature, the max value is respectively 330HV,340HV,370HV.

Foam concrete is used in building energy-saving insulation works, to study its fire performance is very important for further enhancing the fire performance of buildings. Under simulated fire conditions, by determining the compressive strength of foam concrete at different densities, different calcination time and different water content, this experiment studies the effect of these conditions on the fire performance of foam concrete. The results show that in case of fire, the compressive strength loss rate of foam concrete increases with the decreasing of density; to calcine the foam concrete standard specimens whose density are 300kg/m3 and 800kg/m3, their strength loss rates are 66.3% and 25.5%, the compressive strength of foam concrete in the same density increases with the calcination time decreasing, water content has different effects on different densities of foam concrete in the fire security. The foam concrete is non-flammable, but its compressive strength decreases due to the fire of combustible materials and high-temperature calcination.

The laser cladding of Fe power technology was used to repair worn plunger piston surface. The microstructure of cladding layer, binder course and the matrix were observed by OM and SEM. Besides, the micro-hardness of different zones was measured through micro-hardness testing. The results show that the matrix metal microstructure of plunger piston is made of ferrite and austenite. By laser cladding Fe-based power on base metal, the cladding layer grain is fine and uniform, grain growth has obvious direction and finally become dendrites oriented, the microstructure of cladding layer is both second-phase hard particles and Fe-based solutes. The combination between matrix and cladding layer is smooth, belong to metallurgy bonding. The hardness of cladding layer is higher than that of other parts in three parts, the max value of micro-hardness is about 1250HV, it can agree with wear resistance need of plunge piston surface.

Vertebrates diverged from other chordates approximately 500 million years ago and have adopted several modifications of developmental processes. Amphioxus is widely used in evolutionary developmental biology research, such as on the basic patterning mechanisms involved in the chordate body plan and the origin of vertebrates. The fast development of next-generation sequencing has advanced knowledge of the genomic organization of amphioxus; however, many aspects of gene regulation during amphioxus development have not been fully characterized. In this study, we applied high-throughput sequencing on the transcriptomes of 13 developmental stages of Chinese amphioxus to gain a comprehensive understanding of transcriptional processes occurring from the fertilized egg to the adult stage. The expression levels of 3,423 genes were significantly changed (FDR ≤ 0.01). All of these genes were included in a clustering analysis and enrichment of biological functions associated with these clusters was determined. Significant changes were observed in several important processes, including the down-regulation of the cell cycle and the up-regulation of translation. These results should build a foundation for identifying developmentally important genes, especially those regulatory factors involved in amphioxus development and advance understanding of the developmental dynamics in vertebrates.

We describe how the problem of measuring the neutrino mass led us to the development of low-temperature calorimetry. The search for a “17-keV neutrino” concluded with a negative result, but a wide range of applications are now carried on by us and other groups in the fields of x-ray astronomy, recoil measurements of dark matter particles, high precision particle spectrometry, specific heat determinations, neutron detection, and rare decay studies. The masses of the bolometers (calorimeters) extend from 1 mg to 1 kg, nearly as large as for quantum detectors. By lowering the temperature into the 10- 20-mK range, calorimetry is on its way to substantially surpassing the high precision of particle metrology obtainable with the quantum detectors. Calorimeter developments and perspectives are discussed.

The four-and-a-half LIM protein 2 (FHL2) was originally identified to be expressed abundantly in the heart, as well as in a wide range of tissues demonstrated in various studies. The human FHL2 gene expresses different transcripts which are known to differ only in the 5'UTR region. However, little is known about the functional role of the different variants and the mechanism of gene regulation. In the present study, we characterized the different alternative spliced transcripts of FHL2 by in silico analysis and RT-PCR analysis. A novel transcript variant was identified. The FHL2 gene produces transcripts by different 5' exons, which may be responsible for tissue-specific regulation. To study the mechanism of FHL2 gene regulation, the potential promoter region was investigated. We have identified a functional promoter region upstream of the transcription start site. Deletion mutation analysis of 5' flanking region showed that the fragment from -138 to +292 bp have positive regulatory effect. We identified the binding sites of Pax-5/ZF5 in this region and found that Pax-5 and ZF5 expression in HCC samples had a significant positive correlation with FHL2 expression, suggesting a possible role for these transcription factors in the regulation of FHL2 expression.

The visualization and interaction of the photolithography simulation result is useful and challenging. We introduce algorithms that include an automatic sorting algorithm, a transformation model and a dynamic loading algorithm to visualize the large-scale photolithography simulation data in three dimensions in real-time. The automatic sorting algorithm is presented to resort the data output by simulator. And the transformation model converts light intensity data into depth data for 3D modelling. Moreover, the dynamic loading algorithm realizes the out of core visualization. The experimental results demonstrate that our algorithms are effective for photolithography simulation data with 3D large-scale interactive visualization in real-time.

View-frustum culling is one of the key technology , which is used in rendering complicated large-scale scene. The rendering efficiency can be improved greatly in this way which makes real-time rendering possible. In this paper, we divide OBBs(Oriented Bounding Box) in the scene graph by Octree. Then, culling efficiency can be improved a lot by Octree structure. The list of viewed-objects can be determined quickly by this search method from macro structure to micro structure. By means of this algorithm, we can avoid detection between all OBBs and view-frustum and improve rendering efficiency.

To analyze the relationship between the primary mutation at np11778 and the secondary mutations at np9804, np13708, np13730, np15257 in three Chinese pedigrees with Leber's hereditary optic neuropathy (LHON) and to detect the effects of the mutations on LHON.Thirty-seven maternal individuals from three LHON pedigrees and forty-seven normal controls were involved in this study. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing were used to detect the mutations in mitochondrial DNA (mtDNA).All patients and their maternal relatives had the np11778 mtDNA primary mutation. None had the secondary mutations at np9804, np13708 and np13730 and np15257. DNA sequencing of the PCR fragment revealed six new point mutations at np13759, np13928, np13942, np15301, np15323 and np15326.All three Chinese pedigrees with LHON had the mtDNA11778 primary mutation. The frequency of mutation at np13759 in Chinese patients with LHON is higher than that in normal Chinese controls. These findings indicate that np13759 is a new secondary mutation of LHON in Chinese.

We report the development of a waveguide-coupled monolithic Si bolometer for applications in low-background millimeter-wave astrophysical observations. In this device, the absorber of the bolometer is a narrow Bi-coated Si substrate oriented along the E-plane of the waveguide. This design allows efficient coupling of bolometers to waveguide. We measured these devices to have a high coupling efficiency, an electrical responsivity /spl ap/2/spl times/10/sup 9/ V/W, and electrical noise equivalent power (NEP) /spl ap/10/sup -17/ W//spl radic/(Hz) at /spl sim/100 mK. >

The hot-electron microbolometer is a novel low-temperature thermal detector which has potential for very low-noise power measurements at millimeter wavelengths. We are investigating issues in the practical implementation of this detector for low-background applications. We present results from tests of an efficient scheme to couple the detector to waveguide, as well as the expected noise performance of a microbolometer optimized for balloon-borne measurements. The expected NEP of microbolometer in such a measurement is 7/spl times/10/sup 18/ W//spl radic/(Hz) which is nearly a factor of two better than bolometers currently in use. >

Bolometers are used extensively in astrophysics for imaging and spectroscopy at wavelengths between several millimeters and 10 microns. They are particularly useful for applications requiring high sensitivity; current and planned bolometer systems are nearing the sensitivity limit imposed by background photon noise, even in the low-background conditions achieved in observatories on satellites, aircraft, and balloons. Reaching this limit will require new types of bolometers as well as improved preamplifiers to read them out. We describe two types of bolometers optimized for low-background operation and focus on the design and testing of their preamplifier circuits.