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体外培养生殖干细胞产生功能性配子快速获得种质资源，可缩短育种间隔。在性成熟周期较长的养殖鱼类中，它有望作为一种遗传育种的潜在策略。但在养殖鱼类中体外培养精原细胞产生功能性精子仍然是一种挑战。在该研究中，利用Percoll密度梯度离心从中华乌塘鳢精巢中分离了雄性生殖细胞。经细胞形态和分子标记鉴定表明，得到的细胞主要为减数分裂前精原细胞。随后，通过三维（3D）添加激素（Hor）的培养方法，对分离的高纯度中华乌塘鳢精原细胞进行培养，诱导产生游动精子，其比例为培养细胞的9.4%。人工授精实验结果表明，这些体外产生的精子能与中华乌塘鳢成熟卵子受精并产生正常的后代。该研究还发现，在培养系统中添加褪黑素，可显著提高精子产生效率，达到约16%。进一步研究表明，褪黑激素可能通过ERK1/2信号通路激活细胞周期、精子发生和减数分裂相关信号通路，促进精原细胞分化成功能性精子。该鱼类精原细胞3D培养系统有望作为一种新的干细胞育种策略，加速养殖鱼类遗传育种和种质改良。.

Rational molecular design has led to the achievement of β-conformations of terfluorenes that are usually difficult for oligoalkylfluorenes with less than 5 repeat units. Herein, under the guideline of synergistically molecular attractor–repulsor theory (SMART), we design four models of terfluorenes with the possibility of inducing β-conformation in the terfluorene 2,2′-(spiro[fluorene-9,9′-xanthene]-2,7-diyl) bis(9-(4-(octyloxy)phenyl)-fluoren-9-ol) (2O8-DPFOH-SFX) by manipulating the cooperative effects of steric hindrance, hydrogen bonding (HB) and van der Waals (vdW) forces after thermal annealing. For terfluorene 2O8-DPFOH-SFX, the two isomers, raceme and mesomer, with two side chains residing on the two sides and on the same side of the fluorene backbone, respectively, have different packing styles and hence different optical properties: only the raceme isomer could induce the formation of β-conformation. Due to the steric pairing effect of side chains on both sides and the cooperative interaction of the middle spiro[fluorene-9,9′-xanthene] (SFX) group, the racemes precisely interlace with each other and tend to adopt Δ-shaped stacking, which favors a planar π-conjugated structure for the raceme. This is rationalized by the larger content of planar conformations in the 2O8-DPFOH-SFX raceme, according to molecular dynamics (MD) simulations of the condensed phase. Thus, oligofluorenes with definite molecular structure can be considered as notable materials for gaining insight into the structure–property relationships for optical and electronics applications.

The suh gene is crucial in Notch pathway and regulates mammalian gonad development. In this study, the sequences of suh1 and suh2 genes in Yellow River carp (Cyprinus carpio) were verified. The partial 5'-flanking regions of suh1 and suh2 were analyzed and several potential transcription factor-binding sites were identified. Phylogenetic, gene structure, and chromosome synteny analyses revealed that carp suh1 and suh2 were orthologs and homologous to vertebrate suh. Investigation of the expression profiles of suh1 and suh2 with qPCR showed that these genes were abundant in the brain and gonad of carp, with suh1 exhibiting sexual dimorphism expression pattern in gonad. To study the relationship between gonad differentiation and Notch signaling, primordial gonads were exposed to DAPT, an inhibitor of Notch signaling, in vitro and in vivo. The results revealed a significant downregulation of suh1 and other Notch genes in vitro. In addition, expression of male-biased genes, such as amh, dmrt1, etc., was downregulated, whereas that of female-biased genes, such as foxl2, gdf9, etc., was upregulated. When the primordial gonads were subjected to long-term DAPT exposure, an increased proportion of ovary and delay in testis development were observed. These results suggest that suh gene may have a conservative function between teleosts and mammals. Furthermore, Notch signaling was found to be involved in gonad differentiation in Yellow River carp, and DAPT was noted to inhibit and enhance the expression of male- and female-biased genes, respectively, and induce the increase in number of females.

Ovary development appears to be under polygenic control, and is influenced by multiple genetic factors that may vary from organism to organism. To gain a better insight into the molecular mechanisms of carp ovary development, Suppression Subtractive Hybridization (SSH) DNA libraries in two species of Yellow River carp were analyzed. Primordial gonads and stage II ovaries were used as testers, and adult ovaries as drivers. One hundred and fifty differentially-expressed candidate genes were examined by Southern blot microarray hybridization. We identified 41 differentially-expressed genes in the PG (Primordial gonad) library and 37 in the stage II ovary library. Gene Ontology Biological Pathway analysis showed the genes were involved in signal transduction, proteolysis process, cell differentiation, TGF-β signal and other biological responses. Twenty-two candidate genes were selected and further characterized using qRT-PCR. Pvalb, epd, and MYH were found specifically expressed in PG, while bmp2b, desmin and fp1 were specifically expressed in stage II ovary. Our results indicate that these genes could be used as biomarkers of the early development of carp ovary. This finding will provide a basis for further understanding of the complex gonad developmental molecular mechanisms in Yellow River carp.

The current research of kinetostatic characteristics in flexure mechanisms mainly focus on the improvement of accuracy. To reduce or eliminate the parasitic motion is considered as an approach by using the common knowledge of symmetry. However, there is no study on designing the flexure mechanisms with symmetrical features as many as possible for better kinetostatic performance, when considering the resulting cost by the symmetry. In this paper, the concept of degree of symmetry (DoS) is proposed for the first time, which is committed to symmetry design in the phase of conceptual design. A class of flexure mechanisms with 0-DoS, 1-DoS, 2-DoS and 3-DoS are synthesized respectively based on the Freedom and Constraint Topology method. Their overall compliance matrices in an analytical form formulated within the framework of the screw theory are used to analyze and compare the effect of different number of DoS on the kinetostatic characteristics for flexure mechanisms. The finite element analysis (FEA) simulations are implemented to verify the analytical results. These results show that the higher the DoS is, the smaller the parasitic motion error will be. The flexure model with 3-DoS is optimized according to the overall compliance matrix and then tested by using the FEA simulation. The testing result shows that with the best combination parameters, the parasitic motion error for 3-DoS mechanism is almost eliminated. This research introduces a design principle which can alleviate the unwanted parasitic motion for better accuracy.

Since the adoption of some ambiguous and quantitative characters in Flora Republicae Popularis Sinicae 3(1), species identifications of the series Gravesiana have been in disarray, requiring clarification. Two hundred and fifty-nine individuals from 47 different populations were collected for the estimation of morphological characters and phylogenetic analyses. Spores of 26 populations were observed through scanning electron microscope. Our results were different from those of previous research: (1) six identifiable species, rather than five species observed previously, were confirmed in the series Gravesiana, they are A. gravesii, A. juxtapositum, A. mariesii, A. dentatum, A. longzhouensis and A. obovatum, of which the latter three are newly recognized species. (2) Thirteen characters were measured and estimated through the program Mesquite v. 2.71. The character whether the pinna stalks were 1/3-1/2 times longer than the pinna was used to distinguish A. gravesii and A. lianxianense previously and was found to be unreliable here, whereas such characters as the height of the plant (H), pinna aligned forms (FP), number of pinna (NP), pinna margin (M), number of veins flabellate at base (NV), sori number and shape per pinna (NSS), pinna texture (T), and powder-covered or not on the abaxial surface of the pinna (P) are estimated to be stable and reliable characters useful for identification. Descriptions of new species and their retrieve keys are also listed. (3) Surface ornamentations and spore sizes are helpful for us to distinguish species in series Gravesiana.

Objective:The purpose of this study is to investigate the role ofMethods:TheResults:Expression ofConclusion:These preliminary findings suggest that

The study area is located in the north belt of Qingling latitudinal structural belt and contains well developed folds and faults directed EW and the iliceous carbonate sedimentary formations mainly in Lower Paleozoic Group and the sedimentary clastic rocks in Middle-upper Paleozoic Group. Tuyaowa anomaly belt, mainly with Au, As, Sb anomalies, is the favorable target for Au, As, Sb. Zhaizigou-Jianggou-Yujiagou anomaly belt, with Au, Ag, Cu, Zn, Mo anomalie, is the favorable target for Au, Ag, Cu, Zn, Mo. Miaowa-Houling abnomal belt, with Pb, Hg anomalies and Au, Ag, Zn, Mo weak anomalies, is the favorable target looking for Au, Ag, Zn, Mo and Pb. The abnomal belt of Shuigou-Hugou, with Au, Cu, Mo, Pb, V anomalie, is a favorable target for Au, Cu, Mo, Pb and V.

The Ag-Pb Deposit in A He Lan was located in the eastern of the East Kunlun with complex structure, strong magma activity and rich mineral resource. The silver lead-zinc bodies were hosted in Yanshanian biotite adamellite (Jηγ) and blackmica granite diorite (Jγδ) and controlled by the fracture zone. The orebodies produced in vein and lenticular with a length of 200m-820m, the average thickness of 0.42m-6.77m. The ore minerals were mainly galena and limonite and the gangue minerals were quartz, feldspar and biotite. The ore textures mainly contained xenomorphic granular, metasomatie-relict, entrapped, interspersed and cataclastic etc. And the major structures were crumb(granular), veinlet and block in the ore area. The ores were the zinc-lead-silver type rich in lead-silver and poor in zinc. The surrounding rocks were biotitemonzogranite (Jηγ) and the stones were the biotitemonzogranite cataclasite and breccia.

This paper discussed how we can do to design gem stones cut in accordance with their physical properties. Thickening or thinning can be used for the colored gemstones to improve their color. Orienting the table facet is necessary for the star gem stones, cat's eye gem stones and tiger's eye gem stones. It is very important for a pleochroic stone to be cut in proper orienting to show off the different colors. It is desirable to choose cabochon for an opaque gemstone and facet for a transparent gemstone. And a well-crafted geometrical arrangement of facets is key technique to maximize the brilliance and fire of the stones, such as diamond. Do with these skills and get your ideal gems.

The supramolecular approach of fluorenol polymers brings about excellent self-assembly behavior to fabricate organogels and superstructured thin films through highly directional noncovalent interactions. To understand the aggregation effects on electronic structures, the packing structures and the UV/vis absorption spectra of oligofluorenols (PFOHn, n = 1/3-8), with and without OC8H17 side chains, were studied experimentally and theoretically in crystal, amorphous solids, and solutions, respectively. For the ground state in vacuum the steric repulsion between two adjacent fluorenol units renders the PFOH oligomers twisted in a helix conformation, while the molecular aggregation favors the appearance of planar π-conjugated structures. In comparison with the crystal packing, the content of planar conformation (with the torsion angle less than 20°) is increased in amorphous solids. The hydroxyl groups in oligofluorenols facilitate the formation of hydrogen bonding networks. The red shift in absorption spectra was observed in a systematic experimental study of unsubstituted and substituted oligofluorenols with the increasing concentration both in toluene and chloroform solutions. The subsitituted oligofluorenol R-PFOH1 with only one OC8H17 side chain exhibited a shoulder peak at 430-440 nm, which is different from PFOH1 without side chain and 3R-PFO1 with three OC8H17 side chain. Time-dependent density functional theory (TDDFT) calculations, which were carried out on conformation ensembles taken from a series of molecular dynamics (MD) simulations, revealed that the increase in the content of planar π-conjugated conformations is correlated to the red shift in the absorption spectra upon increasing the solution concentrations. The aggregation-induced red-shift in absorption spectra of oligofluorenols, as well as the blue-shift for oligothiophenes, was rationalized in a unified way from the increased (and reduced) content of planar conformations in molecular aggregates.

To explore the relationship between aggressive behaviors, parent-child separation and experience of childhood abuse among junior high school students.A total of 1417 students in ordinary junior high schools from 3 townships in Huoshan, Anhui were involved in this study. Self-made questionnaire was used to estimate aggressive behaviors, parent-child separation in childhood, child abuse and social demographic information of the students under this study.Related scores (2.52 ± 0.78) on physical aggression in boys was higher than in girls (2.29 ± 0.79) while the scores related to anger (2.60 ± 0.82) and hostility (2.58 ± 0.80) in girls, were higher than those in boys (2.41 ± 0.75, 2.47 ± 0.78), all with statistically significant differences (P0.05). Scores related to different types of aggressive behaviors and the scores in total, were higher in students from the senior class (P0.001). Scores on items as verbal aggression, hostility and in total, were higher in those adolescents which had undergone maternal-child separation during their childhood (P0.05). Scores on hostility and in total, were higher in those adolescents which had suffered from father-child separation during their childhood (P0.05). Scores related to anger, hostility and in total, were higher in those adolescents which had undergone both parent-child separation when they were much younger (P0.05). Students who had suffered from various types of repeated abuse showed higher scores in various types of aggressive behaviors and in total, than those who did not have the same experience. Most of the differences among groups were statistically significant (P0.05).Students that suffered parent-child separation in their earlier childhood and with repeated experiences of abuse in childhood appeared to be risk factors causing aggressive behaviors to develop during the age of adolescence.