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Abstract [Objective] Rosa odorata is an important germplasm resource of Rosa, which has high value of appreciation and utilization. In order to promote the development and utilization of the germplasm resources, the chromosome ploidy, floral synthesis, and characteristics of breeding systems of different R. odorata were studied. [Methods] The chromosome ploidy, pollen vitality, stigma vitality, and flower characteristics of 9 R. odorata were observed and determined by flow cytometer and outcrossing analysis. We also analyzed the breeding systems. [Results] (1) 9 R. odorata were identified as diploid, and their flowers were bisexual with bright colors and mostly double or semi-double petals. Male and female flowers of 5 varieties were matured at different time. (2) 9 R. odorata pollen vitalities were low, with the highest vitality of 35.47%. The outcrossing index (OCI) of all varieties was ≥4, and pollen volume-ovule ratio (P/O) values ranged from 6 709 to 75 521. [Conclusion] The breeding system of 9 R. odorata is mainly outcrossing, and the breeding system is affected by many factors, such as the number of pollen grains and petals.

BACKGROUND Rutile, anatase and brookite are TiO2 polymorphs. In the rutile in-situ U-Pb dating, rutile was determined primarily on electron microprobe data and cathodoluminescence images, while these methods sometimes could not effectively distinguish rutile, anatase and brookite. If there are a small number of the TiO2 polymorphs in the sample, the obtained age may be a mixed age with no significant geological significance. Therefore, the identification of TiO2 polymorphs is very important. OBJECTIVES To identify TiO2 polymorphs from the bauxite deposit in central Guangxi. METHODS TiO2 minerals in bauxite from central Guangxi were used as the research object, and laser Raman spectroscopy was applied to the identification of TiO2 isomorphic minerals. RESULTS Four groups of laser Raman spectral lines with different characteristics were identified. The first three groups have laser Raman spectral peaks of anatase, rutile and brookite, respectively. The fourth group has two kinds of laser Raman spectral characteristic lines, one has both anatase characteristic peaks of 144, 198, 397, 513, 636cm-1 and rutile characteristic peaks of 442, 607cm-1, the other has both anatase characteristic peak of 144cm-1 and brookite characteristic peak of 153, 247, 325, 636cm-1. CONCLUSIONS The TiO2 polymorphs of the bauxite deposit includs rutile, anatase, brookite and intermediate minerals that undergo phase transformation. The study indicates that the bauxite deposit in central Guangxi may have undergone a later regional metamorphism, leading to the transformation of TiO2 polymorphs. The laser Raman spectroscopy provides a new method for the identification of TiO2 polymorphs andrutile for in-situ U-Pb dating.

BACKGROUND In recent years, the in situ Hf isotopic determination method of zircon has been widely used in isotopic geochemistry, and has become an important method to explore the genesis of rocks, the source of ore-forming materials and the evolution of crust and mantle. However, for some rocks, the lack of zircon seriously hinders the restriction of formation and evolution. The development of Hf isotopic determination methods for oxide-type U-bearing accessory minerals, such as rutile, cassiterite and columbite is urgently needed. OBJECTIVES In order to accelerate the studies of in situ Hf isotopic determination of oxide-type U-bearing minerals and their application to the geological research. METHODS In situ Hf isotopic analysis of oxide-type U-bearing accessory minerals was reviewed with NEPTUNE multiple-collector inductively coupled plasma-mass spectrometry (MC-ICPMS) and a 193nm excimer laser ablation system. RESULTS Combined with relevant research work in recent years, the development history of Lu-Hf isotope analysis technology for accessory minerals was briefly described, and the latest progress and existing problems in in-situ Hf isotope determination methods for oxide-type uranium-bearing minerals such as rutile, cassiterite and niobite were systematically reviewed. The current technical difficulties such as the correction strategy for isobaric interference, the lack of quality control standard samples, the lower Hf content, and the improvement of analytical sensitivity were discussed in detail. CONCLUSIONS The low Hf content of oxide-type U-bearing accessory minerals requires a larger spot diameter. The femtosecond laser has the characteristics of fine and uniform grain size of the ablation samples. The combination of femtosecond laser and MC-ICPMS (fs-LA-MC-ICPMS) can reduce the spot diameter and improve the spatial resolution, which is the development direction of in situ Hf isotope analysis of oxide-type U-bearing accessory minerals in the future.

BACKGROUND Microbeam analytical technology can be used to accurately analyze the petrography, morphology, structure, component and isotopic composition of ore minerals on the micro-nano scale, which plays a vital role in supporting the detailed research of geoscience. OBJECTIVES To provide a practical technology for visually and quickly identifying the cobalt-bearing minerals and to understand the occurrence of cobalt in the Chambishi copper-cobalt deposit. METHODS Microscopy was combined with microbeam analytical technologies of micro-XRF, EPMA, LA-ICP-MS to develop a method for quickly identifying the cobalt-bearing minerals from copper-cobalt deposits. First, representative thin sections were selected by polarized light microscopy, micro-XRF map scanning was then used to obtain the distribution characteristics of cobalt and combined elements in the thin sections. The polarized light microscopy was used again to identify independent cobalt minerals and cobalt-bearing minerals based on the characteristics of element distribution. Finally, the representative minerals were circled and the main and trace elements were determined by EPMA and LA-ICP-MS. RESULTS The results showed that in the Chambishi Southeast orebody the cobalt not only existed in the form of independent minerals (pentlandite, linnaeite, carrollite), but also occurred in pyrite and pyrrhotite in the form of isomorphism, while the cobalt in the Chambishi West orebody mainly existed in the form of independent mineral—carrollite with a small amount. CONCLUSIONS The combined microbeam analysis method is proposed to quickly and easily identify cobalt-bearing minerals and to study the occurrence of cobalt in the Chambishi Southeast orebody and Chambishi West orebody. It can effectively save the time of identifying minerals by traditional polarized light microscopy and avoid missing identification of some independent cobalt minerals or cobalt-bearing minerals with small particle size or without obvious optical characteristics.

The kinematic characteristics of the ordinary geneva wheel mechanism are determined by the numbers of sheave groove. The drive crank of geneva wheel is the cycloid production mechanism which equals to the mechanism with a variable length,variable speed and along the cycloid moving crank and makes the kinematic characteristic of the geneva mechanism changed. The forming condition of the outside geneva mechanism with uniform movement are analyzed,then on this basis the design method and the mechanism parameters are proposed. The change rule of the uniform movement interval and the influence of movement coefficient on the width of approximate uniform movement interval and the fluctuation quantity of angular velocity in approximate uniform movement interval are analyzed,the calculation method of the width and the fluctuation quantity of angular velocity of the uniform movement interval are given.

For the geneva mechanism,the kinematics coefficient of the geneva mechanism is a constant if the groove number of the ceneva wheel is a constant.The planetary transmission mechanism using as the drive crank of the geneva wheel is equal to the mechanism which has a variable length and a variable speed along the elliptical moving crank.Therefore the kinematics characteristics of the geneva mechanism can be changed.By using elliptic curve generated within the planetary transmission mechanism as the crank drive geneva mechanism,select mechanism parameters appropriately,can make thegeneva wheel movement in the middle with a uniform motion characteristics.The synthesis method of the combined geneva mechanism is put forward based on the kinematics coefficient.

Sea ice monitoring is one of the important guarantees for marine operation and transport. The space borne remote sensing techniques have the advantages of wide area surveillance, multi-temporal resolution, prompt acquisition, and high precision. They have become one of the key sea ice monitoring techniques. The new Chinese satellite HJ-1A/B CCD images were used in the sea ice monitoring of the Nanpu sea area in winter, during the time from Nov. 29, 2008 to Feb. 21, 2009. A fast processing work flow was established based on the object-oriented information extraction technology. It was used to map the change of the ice area during the period. According to the ice area change, the ice sea distribution, and the historical meteorological information, the ice period was divided into: initial ice (early Dec., 2008 to the end of Dec., 2008), abounding ice (from the end of Dec., 2008 to the end of Jan., 2009), ice thawing (from the end of Jan., 2009 to the end of Feb., 2009). The work contributes to the safe construction of the artificial islands in the Nanpu-4 structure during the icebound season. The study shows that the remote sensing technology is a practical and effective technical means for the sea ice security monitoring of oil fields' exploration, development and engineering construction in beaches. 摘 要: 海冰监测是海上生产作业和运输的重要保障之一，遥感技术以其范围大、多时相、快速、准确等特点成为海冰监测的重要手段。采用最新发射的国产卫星HJ-1A/B星CCD数据，对冀东南堡海域2008年11月29日到2009年2月21日的冬季冰情进行全程监测，建立了基于面向对象的信息提取技术的滩海冰情遥感监测快速处理流程，并运用处理流程对南堡海域各时相的影像解译结果进行统计分析，绘制了整个冰期的冰面积变化统计图。根据冰面积变化统计图、各时相海冰分布图，结合历史气象信息进行分析，得出该海域海冰冰期划分结果：初冰期（2008年12月初至2008年12月底），盛冰期（2008年12月底至2009年1月底）及融冰期(2009年1月底至2009年2月底)。此冰期划分结果对正在建设中的南堡4号构造人工岛冬季冰期的安全施工起到了重要指导作用，表明遥感技术能对油田滩海冰情进行及时、全面、准确的监测，是油田滩海工程冬季海冰安全监测实用、有效的技术手段。图5表3参16 Key words: remote sensing technique, offshore engineering, sea ice monitoring, ice period division, Nanpu sea area

The process of transformation and superposition from the Paleo-Asian Ocean to the Paleo-Pacific Ocean tectonic systems have been a critical scientific issue. However, the final closure of the Paleo-Asian Ocean and the initial subduction time of the Paleo-Pacific Ocean, together with the conversion between them in Northeast China, still remain controversial. The Triassic granites in the Jiamusi Block are located in the key position of Northeast China, recording the conversion process of two tectonic domains. Through systematic geochronology and geochemical studies, it can provide important constraints for revealing the superposition and conversion mechanism of the Paleo-Asian Ocean and the Paleo-Pacific Ocean and the early subduction history of the Paleo-Pacific Ocean plate. In this study, the granites in Jiamusi Block were formed in the Early–Middle Triassic (250–245 Ma), characterized by high Si, rich alkali, poor Mg, and are obviously enriched in light rare earth elements and large ion lithophile elements, depleting in high field strength elements such as Nb, Ta, and Ti. They have typical characteristics of continental magmatic arc, deriving from partial melting of amphibolite facies and garnet amphibolite facies mafic lower crust. Combined with zircon Hf isotope results, zircon εHf(t) values are −6.52 to + 9.79, and the two-stage Hf model ages are 0.6–1.7 Ga, indicating that the magma should be derived from a relative younger crustal source, and some ancient materials may be added. Moreover, based on the spatial-temporal framework and Hf isotope characteristics of magmatism in Northeast China, we believe that the Jiamusi Block belonged to an exotic block. Meanwhile, combined with geochronological and geochemical data of igneous rocks on the Jiamusi Block, we suggest that the evolution of Jiamusi Block was dominated by the Paleo-Pacific Ocean rather than Paleo-Asian Ocean during the Triassic, which means the subduction of Paleo-Pacific Ocean plate initiated at least in Early Triassic. [ABSTRACT FROM AUTHOR]

We developed a Prussian blue@Au nanoparticles/SiO2-cavities/indium tin oxide (ITO) electrode for a novel non-enzymatic hydrogen peroxide detection. The ordered SiO2 cavities were fabricated on the ITO electrode using the close-packed ordered polystyrene spheres (PS) as templates. The PB@Au nanoparticles were prepared using a two-step process in which gold nanoparticles were deposited at the bottom of the SiO2 cavity by electrochemical methods, while Prussian blue was introduced into the AuNP surface by chemical deposition. The submicron-sized conductive region and the domain-limiting effect of the insulating SiO2 cavity give the electrode the characteristics of a microelectrode, enabling it to exhibit unique electrochemical properties during the electrochemical reduction of H2O2. The proposed PB@Au/SiO2 cavity/ITO electrode was further used for detecting H2O2 with a wide linearity range of 0.08–8 mM and a low detection limit of 0.3 μM. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer is a highly heterogeneous disease, which makes it challenging to develop effective targeted therapies. Although the potassium voltage‐gated channel subfamily D (KCND) channels, particularly KCND2 (also known as Kv4.2), have found evidence of involvement in the occurrence and development of various cancers, there are still some limitations in our understanding of KCND2's roles in gastric cancer. Methods: We analyzed the correlation between KCND2 expression and clinical features as well as immune infiltration using the Cancer Genome Atlas (TCGA) database. Functional assays of KCND2 were conducted using Cell counting Kit‐8 (CCK8), clone formation assay and cell cycle analysis. Additionally, immunofluorescence, flow cytometry and quantitative real‐time polymerase chain reaction (qRT‐PCR) techniques were used to investigate tumor proliferation and immune cell infiltration at different levels of KCND2 expression in vivo. Results: KCND2 was markedly elevated in gastric cancer and its expression appeared to link to different grades, T stages, and N stages. In addition, KCND2 was an independent predictor of prognosis, and its elevated levels in TCGA database revealed a more unfavorable prognosis for patients with gastric cancer. KCND2 strengthened the viability at the cellular level by boosting the proliferation of gastric cancer cells and reducing their death rate. Additionally, it also highlights that KCND2 the abilities of proliferating of gastric cancer cells by stimulating NF‐κB both in cell and animal levels. In addition, the findings provided proof that in animal levels, KCND2 might regulate the immune system by associating with promoting M2 macrophages, which are known to play critical roles in cancer progression. Mechanistically, KCND2 was found to lead to the infiltration of M2 macrophages through activation of NF‐κB, ultimately promoting the advancement of gastric cancer. Conclusion: Overall, these findings suggest that KCND2 is likely to be available as an underlying therapeutic target for gastric cancer. [ABSTRACT FROM AUTHOR]