烤烟品种资源的RAPD分析

从156个随机引物中筛选出30个引物,对来自国内外的31个烤烟品种进行了遗传多样性和亲缘关系的RAPD分析。在检测的246个位点中,127个位点为多态位点（52％）。聚类分析表明,不同烤烟品种之间存在明显差异,31个品种基本上可分为4大类,品种最多的第一大类（19个）主要由来自美国的Orinoco烤烟选育而成,反映了我国现在推广的烤烟品种遗传基因比较狭窄。研究结果表明,RAPD技术可用于烤烟品种的鉴别和纯度测定。研究为烤烟杂种育种中亲本的选配提供了一定的理论依据。     

PAGE活性染色法分析D.radiodurans过氧化氢酶和超氧化物歧化酶

用PAGE活性染色法分析了D．rndiodurans过氧化氢酶（Cat）和超氧化物歧化酶(SOD)._2种同种异型D．radiodurans（RI和Sark）的Cat在电泳带型上存在差异,两者Kat均可分为A、B和C3条带,但各带所占比例明显不同。SOD的分析结果表明,D.radioduransSOD以Fe2 和Mn2 离子的嵌合体形式存在,其中Fe－SOD成分占90％以上。PAGE活性染色法可检出Cat和SOD的最低菌体总蛋白量分别为1.2和2.0μg。     

Growth patterns in brooding dinosaurs reveals the timing of sexual maturity in non-avian dinosaurs and genesis of the avian condition

The timing of sexual maturation in non-avian dinosaurs is not known. In extant squamates and crocodilians it occurs in conjunction with the initial slowing of growth rates as adult size is approached. In birds (living dinosaurs) on the other hand, reproductive activity begins well after somatic maturity. Here we used growth line counts and spacing in all of the known brooding non-avian dinosaurs to determine the stages of development when they perished. It was revealed that sexual maturation occurred well before full adult size was reached-the primitive reptilian condition. In this sense, the life history and physiology of non-avian dinosaurs was not like that of modern birds. Palaeobiological ramifications of these findings include the potential to deduce reproductive lifespan, fecundity and reproductive population sizes in non-avian dinosaurs, as well as aid in the identification of secondary sexual characteristics.     

Radially Oriented Single‐Crystal Primary Nanosheets Enable Ultrahigh Rate and Cycling Properties of LiNi0.8Co0.1Mn0.1O2 Cathode Material for Lithium‐Ion Batteries

Ni‐rich Li[Ni_xCo_yMn_1?x?y]O₂ (x ≥ 0.8) layered oxides are the most promising cathode materials for lithium‐ion batteries due to their high reversible capacity of over 200 mAh g^?1. Unfortunately, the anisotropic properties associated with the α‐NaFeO₂ structured crystal grains result in poor rate capability and insufficient cycle life. To address these issues, a micrometer‐sized Ni‐rich LiNi_0.8Co_0.1Mn_0.1O₂ secondary cathode material consisting of radially aligned single‐crystal primary particles is proposed and synthesized. Concomitant with this unique crystallographic texture, all the exposed surfaces are active {010} facets, and 3D Li⁺ ion diffusion channels penetrate straightforwardly from surface to center, remarkably improving the Li⁺ diffusion coefficient. Moreover, coordinated charge–discharge volume change upon cycling is achieved by the consistent crystal orientation, significantly alleviating the volume‐change‐induced intergrain stress. Accordingly, this material delivers superior reversible capacity (203.4 mAh g^?1 at 3.0–4.3 V) and rate capability (152.7 mAh g^?1 at a current density of 1000 mA g^?1). Further, this structure demonstrates excellent cycling stability without any degradation after 300 cycles. The anisotropic morphology modulation provides a simple, efficient, and scalable way to boost the performance and applicability of Ni‐rich layered oxide cathode materials.     

Axial resolution enhancement of light‐sheet microscopy by double scanning of Bessel beam and its complementary beam

The side lobes of Bessel beam will create significant out‐of‐focus background when scanned in light‐sheet fluorescence microscopy (LSFM), limiting the axial resolution of the imaging system. Here, we propose to overcome this issue by scanning the sample twice with zeroth‐order Bessel beam and another type of propagation‐invariant beam, complementary to the zeroth‐order Bessel beam, which greatly reduces the out‐of‐focus background created in the first scan. The axial resolution can be improved from 1.68 μm of the Bessel light‐sheet to 1.07 μm by subtraction of the two scanned images across a whole field‐of‐view of up to 300 μm × 200 μm × 200 μm. The optimization procedure to create the complementary beam is described in detail and it is experimentally generated with a spatial light modulator. The imaging performance is validated experimentally with fluorescent beads as well as eGFP‐labeled mouse brain neurons.      

Apple Fruit Diameter and Length Estimation by Using the Thermal and Sunshine Hours Approach and Its Application to the Digital Orchard Management Information System

In apple cultivation, simulation models may be used to monitor fruit size during the growth and development process to predict production levels and to optimize fruit quality. Here, Fuji apples cultivated in spindle-type systems were used as the model crop. Apple size was measured during the growing period at an interval of about 20 days after full bloom, with three weather stations being used to collect orchard temperature and solar radiation data at different sites. Furthermore, a 2-year dataset (2011 and 2012) of apple fruit size measurements were integrated according to the weather station deployment sites, in addition to the top two most important environment factors, thermal and sunshine hours, into the model. The apple fruit diameter and length were simulated using physiological development time (PDT), an indicator that combines important environment factors, such as temperature and photoperiod, as the driving variable. Compared to the model of calendar-based development time (CDT), an indicator counting the days that elapse after full bloom, we confirmed that the PDT model improved the estimation accuracy to within 0.2 cm for fruit diameter and 0.1 cm for fruit length in independent years using a similar data collection method in 2013. The PDT model was implemented to realize a web-based management information system for a digital orchard, and the digital system had been applied in Shandong Province, China since 2013. This system may be used to compute the dynamic curve of apple fruit size based on data obtained from a nearby weather station. This system may provide an important decision support for farmers using the website and short message service to optimize crop production and, hence, economic benefit.     

Synonymous Codon Usage Bias in Plant Mitochondrial Genes Is Associated with Intron Number and Mirrors Species Evolution

Synonymous codon usage bias (SCUB) is a common event that a non-uniform usage of codons often occurs in nearly all organisms. We previously found that SCUB is correlated with both intron number and exon position in the plant nuclear genome but not in the plastid genome; SCUB in both nuclear and plastid genome can mirror the evolutionary specialization. However, how about the rules in the mitochondrial genome has not been addressed. Here, we present an analysis of SCUB in the mitochondrial genome, based on 24 plant species ranging from algae to land plants. The frequencies of NNA and NNT (A- and T-ending codons) are higher than those of NNG and NNC, with the strongest preference in bryophytes and the weakest in land plants, suggesting an association between SCUB and plant evolution. The preference for NNA and NNT is more evident in genes harboring a greater number of introns in land plants, but the bias to NNA and NNT exhibits even among exons. The pattern of SCUB in the mitochondrial genome differs in some respects to that present in both the nuclear and plastid genomes.     

The PWWP domain of mammalian DNA methyltransferase Dnmt3b defines a new family of DNA-binding folds

The PWWP domain is a weakly conserved sequence motif found in > 60 eukaryotic proteins, including the mammalian DNA methyltransferases Dnmt3a and Dnmt3b. These proteins often contain other chromatin-association domains. A 135-residue PWWP domain from mouse Dnmt3b (amino acids 223--357) has been structurally characterized at 1.8 A resolution. The N-terminal half of this domain resembles a barrel-like five-stranded structure, whereas the C-terminal half contains a five-helix bundle. The two halves are packed against each other to form a single structural module that exhibits a prominent positive electrostatic potential. The PWWP domain alone binds DNA in vitro, probably through its basic surface. We also show that recombinant Dnmt3b2 protein (a splice variant of Dnmt3b) and two N-terminal deletion mutants (Delta218 and Delta369) have approximately equal methyl transfer activity on unmethylated and hemimethylated CpG-containing oligonucleotides. The Delta218 protein, which includes the PWWP domain, binds DNA more strongly than Delta369, which lacks the PWWP domain.     

New therapy with XLQ® to suppress chronic prostatitis through its anti-inflammatory and antioxidative activities

Chronic prostatitis is a common urological disease. The etiology of this disease and effective therapy for its treatment are yet to be elucidated. We investigated the functions of XLQ^® in chronic nonbacterial prostatitis using a complete Freund's adjuvant-induced rat model. Prostates and blood samples were collected for further evaluation after oral gavage with XLQ ^® or a vehicle for 4 weeks. The results showed that XLQ ^® significantly decreased the prostate index, ameliorated the histopathologic changes, and reduced CD3+ and CD45+ cell infiltration in the prostate stroma. Further study showed that XLQ ^® suppressed the expression of proinflammatory cytokines, such as interleukin (IL)-1β, IL-2, IL-6, IL-17A, monocyte chemoattractant protein-1, and tumor necrosis factor-α. XLQ ^® showed a strong antioxidant capacity by enhancing the activities of antioxidative enzymes (e.g., total superoxide dismutase, catalase, and glutathione peroxidase) and decreasing the level of lipid peroxidation products (malondialdehyde). Moreover, XLQ ^® can suppress the activation of nuclear factor-κB and P38-mitogen-activated protein kinase signaling pathways. In summary, XLQ ^® has affirmative effects on chronic prostatitis, which could be attributed to its anti-inflammatory and antioxidative capacities. On the basis of these results, XLQ ^® can be developed as an effective and safe therapy for chronic prostatitis.