New Methods in Gravitational and Seismic Reflection Exploration

For the purpose of regional gravity survey, a completely automatic terrain correction method has been developed. The advantages of previous methods developed by others have been taken over with some modifications, also a new idea for the inner zone correction has been presented. At first, the whole area under investigation is divided into a grid of equal squares of convenient size for the automatic computation. The terrain effect of the far distant zone (r>50 km) is neglected. The terrain effect of the distant zone (30<r<50 km) is evaluated by approximating the prism as a vertical line with all mass centred on it, so, the line mass formula is used for this compulation. The terrain correction of the intermediate zone (2<r≤30 km) is estimated by approximating prism as a segment of a hollow cylinder of different sizes. Specifically, the side of the prism is treated as 4 km in the zone (20<r≤30 km), 2 km in the zone (15<r≤20 km) and 1 km in the zone (2<r≤15 km). The terrain effect of near zone 2 (0.5<r<2 km) is calculated by approximating the terrain as a vertical prism with a horizontal lower face and an upper face constantly sloping towards the station. A simplified formula is used for this computation. The terrain effect of near zone 1 (r≤0.5 km), that is, the square with the gravity station inside, is obtained by triangulating that square with an additional four elevation values provided at the four corners of the square. Since these four heights are read directly from four points on the Ordnance Survey map, they are relatively accurate, so that the triangulated prisms will more approach the real terrain. The gravitational effect of individual prisms in near zone 1 is obtained by integrating gravity over the volume. As a result, the rather complicated formulae are derived. The software MATERRAIN has been developed on the VAX/UNIX operating system not only to make terrain corrections, but to make the free-air and Bouguer corrections. The output from the program is a Bouguer anomaly. The method is tested by the gravity data in the Southern Uplands of Scotland and the results are satisfactory. It is found that some of the original terrain corrections provided by the BGS are underestimated and need to be modified. The method is entirely automatic and easy to use. With respect to reflection seismology, a new experiment was conducted aimed at understanding the wave propagation in volcanic rocks, finding new means of obtaining conventional reflection seismic data, and extracting the weak signals in the presence of noise. To accommodate this, a new areal 'RAZOR' array was designed. Three-component geophones lie on one of two concentric circles of radii 75 and 130 m. The determination of the array dimension is based on several factors such as the wavelength of signal, the true dip of deep reflectors. Three-component seismic data were acquired over the basalt in the Midland Valley of Scotland using an MDS-10 Data System. The SEG-Y data were transformed into an ASCII-coded format and then rotated onto a new coordinate system. The study of characteristics of field data shows that 3-component seismograms are characterised by strong reverberations lasting as long as 500 ms. The reverberation patterns vary from station to station. The horizontal components exhibit larger amplitudes and lower frequency than the vertical component. Furthermore, the data from the inner stations are believed to be more affected by surface conditions than the data from the outer stations. The display of the vertical and radial components from the outer stations shows a line of reflection events at about 420 ms; there are no clear events on the transverse section. By applying a spatial directional filter to each component of seismic data, it is shown that there is more information in the horizontal component passing through the filter than the vertical component. This is attributed to the far larger amplitudes of the horizontal components, which may dominate the polarisation direction of particle motions. The energy variation diagram of each shot shows quantitatively that the radial component receives much more energy than the others. In order to extract weak signals in the presence of noise, a bandpass frequency filter with a low cut-off of 20 Hz and a slope of 30 dB/octave, and a high cut-off of 60 Hz and a slope of 70 dB/octave is applied. The filtered data reveal that the filter can reject part of the low frequency reverberations (<20 Hz) and high frequency noise. For most of high reverberations within the bandwidth, the filter does little to improve the data. Predictive deconvolution filtering shows that it is very good at compressing the wavelets and attenuating the amplitude of reverberations

2,4-Dichloro-6-[2-meth­oxy-4-(prop-2-en-1-yl)phen­oxy]-1,3,5-triazine

The title compound, C13H11Cl2N3O2, was obtained by the reaction of eugenol and cyanuric chloride. The dihedral angle between the benzene and triazine rings is 87.56 (4)°. Two C atoms of the allyl group are disordered over two sites in a 0.72 (2):0.28 (2) ratio

Analysis of the Preventive Medicine Undergraduate Curriculum in China: The West China School of Public Heath Experience: A Case Study

In China, the preventive medicine undergraduate professional training program is the major approach to training public health practitioners. The history of undergraduate education in public health/preventive medicine in China is reviewed utilizing the West China School of Public Health at Sichuan University as an example for analyzing this undergraduate major and its curriculum. Needed reforms in the Chinese undergraduate preventive medicine programs are presented, including review of the traditional preventive medicine course content, revision of its curriculum structure, the need to increase practical experience and to develop variety in teaching and assessment techniques, and systematic planning for curriculum reform. Current efforts at reform of the preventive medicine undergraduate program at Sichuan University’s West China School of Public Health are presented

Identification, Characterization, and Effects of Xenopus laevis PNAS-4 Gene on Embryonic Development

Apoptosis plays an important role in embryonic development. PNAS-4 has been demonstrated to induce apoptosis in several cancer cells. In this study, we cloned Xenopus laevis PNAS-4 (xPNAS-4), which is homologous to the human PNAS-4 gene. Bioinformatics analysis for PNAS-4 indicated that xPNAS-4 shared 87.6% identity with human PNAS-4 and 85.5% with mouse PNAS-4. The phylogenetic tree of PNAS-4 protein was also summarized. An analysis of cellular localization using an EGFP-fused protein demonstrated that xPNAS-4 was localized in the perinuclear region of the cytoplasm. RT-PCR analysis revealed that xPNAS-4, as a maternally expressed gene, was present in all stages of early embryo development. Whole-mount in situ hybridization showed that xPNAS-4 was mainly expressed in ectoderm and mesoderm. Furthermore, microinjection of xPNAS-4 mRNA in vivo caused developmental defects manifesting as a small eye phenotype in the Xenopous embryos, and as a small eye or one-eye phenotype in developing zebrafish embryos. In addition, embryos microinjected with xPNAS-4 antisense morpholino oligonucleotides (MOs) exhibited a failure of head development and shortened axis

The multiplexed light storage of Orbital Angular Momentum based on atomic ensembles

The improvement of the multi-mode capability of quantum memory can further improve the utilization efficiency of the quantum memory and reduce the requirement of quantum communication for storage units. In this letter, we experimentally investigate the multi-mode light multiplexing storage of orbital angular momentum (OAM) mode based on rubidium vapor, and demultiplexing by a photonic OAM mode splitter which combines a Sagnac loop with two dove prisms. Our results show a mode extinction ratio higher than 80$\%$ at 1 $\mu$s of storage time. Meanwhile, two OAM modes have been multiplexing stored and demultiplexed in our experimental configuration. We believe the experimental scheme may provide a possibility for high channel capacity and multi-mode quantum multiplexed quantum storage based on atomic ensembles

Fasciolopsis buski (Digenea: Fasciolidae) from China and India may represent distinct taxa based on mitochondrial and nuclear ribosomal DNA sequences

Sequences of primers used to amplify fragments of Fasciolopsis buski mitochondrial genome. (DOCX 17 kb

Enhanced hydrogen production using a tandem biomass pyrolysis and plasma reforming process

Converting biomass into energy and fuels is considered a promising strategy for replacing the exhaustible fossil fuels. In this study, we report on a tandem process that combines cellulose pyrolysis and plasma-assisted reforming for H-2 production. The hybrid pyrolysis/plasma reforming process was carried out in a two-stage reaction system incorporating a coaxial dielectric barrier discharge (DBD) plasma reactor. The effects of discharge power, steam, reforming temperature, and catalyst on the reaction performance were investigated. The results show that low temperatures are preferred in the non-catalytic plasma reforming process, whereas high temperatures are desired to achieve a high H-2 yield and a high H-2 selectivity in the plasma-catalytic reforming system. The synergistic effect of plasma catalysis was dominant in the plasma-catalytic reforming process at 250 degrees C. In contrast, the catalyst, rather than the plasma, played a dominant role in the plasma-catalytic reforming at higher temperatures (550 degrees C). Using Ni-Co/Al(2)O3 at a reforming temperature of 550 degrees C, a high H-2 yield of 26.6 mmol/g was attainted, which was more than 8 times and about 100% greater than that obtained using plasma alone and catalyst alone, respectively. This work highlights the potential of non-thermal plasmas in lowtemperature biomass conversion.European Union [823745]; Science and Technology Ex-change Project of the Chinese Ministry of Science and Technology [2021-12-2]; Education Cooperation Project between China and Central Eastern European Countries [2021086]; British Council Newton Fund Institutional Links Grant [623389161]; Scientific and Technological Research Council of Turkey (TUBITAK) [219M123]; Chinese Scholarship Council; University of LiverpoolThis project has received the funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska Curie Grant Agreement (No. 823745) . C. Quan and N. Gao gratefully acknowledge funding from the Science and Technology Ex-change Project of the Chinese Ministry of Science and Technology (No. 2021-12-2) and the Education Cooperation Project between China and Central Eastern European Countries (No. 2021086) . X. Tu gratefully acknowledges the British Council Newton Fund Institutional Links Grant (No. 623389161) . J. Yanik gratefully acknowledges funding from the Scientific and Technological Research Council of Turkey (TUBITAK Project Contract no. 219M123) . W. Wang thanks the University of Liverpool and the Chinese Scholarship Council for funding this PhD

Biomass volatiles reforming by integrated pyrolysis and plasma-catalysis system for H2 production: Understanding roles of temperature and catalyst

Biomass utilization is considered a carbon–neutral way to simultaneously tackle the energy crisis and environmental contamination. Challenges still exist to hinder its application, such as low products yield, tar blockage, harsh condition and inferior stability. This paper aims to study whether the newly developed integrated pyrolysis and plasma-catalysis system can be applied into practice of H2 production from real biomass volatiles, and to understand roles of temperature and catalyst. The experiments were performed in a two-stage reactor embedded with a coaxial dielectric barrier discharge plasma zone. Impacts of operating conditions (i.e. discharge power, steam input, heat supply and catalyst packing) on H2 production were investigated. The results show that proper input of discharge power and steam can promote H2 production. Heating supply is recognized as two different effects on plasma-only and plasma-catalysis systems, since reaction temperature elevation acts as inhibitor to plasma characters and cut down the contribution of plasma reforming. After packing bimetallic Ni-Fe/γ-Al2O3 catalyst into plasma, optimal 47.65 mmol/g of H2 can be attained at reforming temperature of 500 ℃, with synergy effects observed. Plasma-catalysis system also outperformed in tar cracking, tar elimination and stability test, attributed to plasma assistance. This work provides an alternative to construct a new plasma-catalysis process for H2 production from biomass volatiles or to couple plasma technology with existing biomass conversion industries for preferable energy and fuel production, highlighting its promising commercialization prospects