The primary root procambium contributes to lateral root formation through its impact on xylem connection

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The essential differences in microbial and chemical components of musk of different qualities secreted by captive male forest musk deer (Moschus berezovskii)

Musk is a precious raw material and ingredient in Chinese traditional medicine. The production of unqualified musk has become a puzzling problem in forest musk deer (FMD) breeding. However, what the essential differences between so-called unqualified musk and mature qualified musk have not yet been elucidated. In this study, 12 musk samples were collected and separated into two groups according to their external properties. One group is white or black cream-like secretion with sour or unpleasant odour (MM); the other group is brown or blackish brown solid secretion with pleasant fragrance (DM). Next-generation sequencing and gas chromatography-mass spectrometry were used to explore the essential differences between the DM and MM groups in microbial and chemical compositions. The results indicate that the DM group has more heterogenous microbial structure but simpler relationships among microbial communities. LEfSe analysis showed that 14 taxa at the genus level could be used to distinguish the DM and MM groups and Bacillus, Paracoccus, tenoteophomonas, Mycobacterium and Leuconostoc were more abundant in the DM group (P < 0.05). In addition, six compounds were identified to specifically distinguish the DM and MM groups under the OPLS-DA model. PICRUSt analysis revealed that metabolic pathways such as carbohydrate metabolism, nucleotide metabolism, energy metabolism, transport and catabolism were enriched in the DM group. All these findings of differences in microbiota and chemical compositions would provide potential clues for MM quality improvement and new evidence for the scientific establishment of a quality evaluation standard for musk.     

Optimum timing for integrated pest management: Modelling rates of pesticide application and natural enemy releases

Many factors including pest natural enemy ratios, starting densities, timings of natural enemy releases, dosages and timings of insecticide applications and instantaneous killing rates of pesticides on both pests and natural enemies can affect the success of IPM control programmes. To address how such factors influence successful pest control, hybrid impulsive pest-natural enemy models with different frequencies of pesticide sprays and natural enemy releases were proposed and analyzed. With releasing both more or less frequent than the sprays, a stability threshold condition for a pest eradication periodic solution is provided. Moreover, the effects of times of spraying pesticides (or releasing natural enemies) and control tactics on the threshold condition were investigated with regard to the extent of depression or resurgence resulting from pulses of pesticide applications. Multiple attractors from which the pest population oscillates with different amplitudes can coexist for a wide range of parameters and the switch-like transitions among these attractors showed that varying dosages and frequencies of insecticide applications and the numbers of natural enemies released are crucial. To see how the pesticide applications could be reduced, we developed a model involving periodic releases of natural enemies with chemical control applied only when the densities of the pest reached the given Economic Threshold. The results indicate that the pest outbreak period or frequency largely depends on the initial densities and the control tactics.     

Investigation on the Enhanced Fluorescence Emission from Self-Assembled Au Nanorod Film

Plasmonics - A two-dimension distributed metallic nanostructure substrate containing two-dimensional array of Au nanorods with different configurations is prepared via a self-assembly method....     

Stabilization of population dynamics via threshold harvesting strategies

We study two different harvesting/thinning control strategies in the framework of one-dimensional discrete time population models. They have the common feature of considering a threshold population size, commonly called Biomass at the limit, under which the population is not altered, and they differ in how the harvesting/thinning is applied when that threshold is surpassed: one uses the well known proportional feedback control, whereas the other employs the recently proposed target oriented control. We focus on the possibility of applying these strategies to control the chaotic behaviour predicted by some one-dimensional discrete time population models. We discuss the basic properties of both strategies and compare them with other simpler control methods. Particularly, we show that increasing the threshold does not affect, or almost does not affect, a stable exploited population as long as the threshold is lower than the carrying capacity of the system.     

Sociality and oxytocin and vasopressin in the brain of male and female dominant and subordinate mandarin voles

The dominant–subordinate hierarchy in animals often needs to be established via agonistic encounters and consequently affects reproduction and survival. Differences in brain neuropeptides and sociality among dominant and subordinate males and females remain poorly understood. Here we explore neuropeptide levels and sociality during agonistic encounter tests in mandarin voles. We found that dominant mandarin voles engaged in higher levels of approaching, investigating, self-grooming and exploring behavior than subordinates. Dominant males habituated better to a stimulus vole than dominant females. Dominant males displayed significantly less oxytocin-immunoreactive neurons in the paraventricular nuclei and more vasopressin-immunoreactive neurons in the paraventricular nuclei, supraoptic nuclei, and the lateral and anterior hypothalamus than subordinates. Dominant females displayed significantly more vasopressin-immunoreactive neurons in the lateral hypothalamus and anterior hypothalamus than subordinates. Sex differences were found in the level of oxytocin and vasopressin. These results indicate that distinct parameters related to central nervous oxytocin and vasopressin are associated with behaviors during agonistic encounters in a sex-specific manner in mandarin voles.     

Theoretical study on the mechanisms of polyethylene electrical breakdown strength increment by the addition of voltage stabilizers

Journal of Molecular Modeling - Glycoprotein D (gD) is an essential protein of herpes simplex virus-1 (HSV-1) that targets the structurally unrelated receptors HVEM and nectin-1. Receptor binding...     

Microsatellite and chloroplast DNA analyses reveal no genetic variation in a beach plant Surianana maritima on the Paracel Islands,China

Genetic variation within and among six natural populations of beach plant Suriana maritima on the Paracel Islands of China was assessed using SSR and chloroplast DNA sequence analysis. The results showed a complete absence of genetic variation between individuals either within or among populations. The cumulative consequences of a founder effect, selfing, and inbreeding may be responsible for the loss of genetic diversity in S. maritima.     

中国广西澳汉蚱属一新种记述（直翅目：蚱总科：枝背蚱科）

记述采自广西大明山自然保护区澳汉蚱属 Austrohancockia Günther 1新种,即波缘澳汉蚱Austrohancockia undatimarginis Deng & Zheng sp. nov.。新种因侧面观背板上缘在肩部之前具3个呈波状凹陷;沟前区侧隆线下方及肩前的下方各具1对瘤突,前者为小,后者为大;背板在肩部之间中隆线两侧具2对短纵隆线,肩角宽大近弧形,明显向外突出区别于属内其它种。模式标本保存在陕西师范大学动物所标本室。     

Cytosolic acidification precedes nitric oxide removal during inhibition of ABA-induced stomatal closure by fusicoccin

The role of nitric oxide (NO) and the relationship between NO and cytosolic pH during inhibition of ABA effect by fusicoccin (FC) in guard cells of Vicia faba were analyzed. ABA induced NO generation and stomatal closure, but FC inhibited the effects of ABA. Treatment with 2-(4-carboxyphenyl)-4,4,5,5-tetra-methylimidazoline-1-oxyl-3-oxide (cPTIO) and N^G-nitro-L-Arg-methyl ester (L-NAME) mimicked the effects of FC. These data suggest that inhibition of ABA effect by FC is possibly related to the decreasing in the NO level. Furthermore, like cPTIO, FC not only suppressed stomatal closure and NO level in guard cells treated with NO donor sodium nitroprusside (SNP), but also reopened stomata, which had been closed by ABA, and reduced the level of NO in guard cells that had been produced by ABA, indicating that FC caused NO removal. Butyric acid simulated the effects of FC on the stomatal aperture and increased NO levels in guard cells treated with SNP and had been closed by ABA, and both FC and butyric acid surely reduced cytosolic pH, which demonstrates that cytosolic acidification mediates FC-induced NO removal. Taken together, our results show that FC induces NO removal and reduces NO level via cytosolic acidification in guard cells, thus inhibiting ABA effect.