Parameter-tuning Networks: Experiments and Active Walk Model

The tuning process of a large apparatus of many components could be represented and quantified by constructing parameter-tuning networks. The experimental tuning of the ion source of the neutral beam injector of HT-7 Tokamak is presented as an example. Stretched-exponential cumulative degree distributions are found in the parameter-tuning networks. An active walk model with eight walkers is constructed. Each active walker is a particle moving with friction in an energy landscape; the landscape is modified by the collective action of all the walkers. Numerical simulations show that the parameter-tuning networks generated by the model also give stretched exponential functions, in good agreement with experiments. Our methods provide a new way and a new insight to understand the action of humans in the parameter-tuning of experimental processes, is helpful for experimental research and other optimization problems.Comment: 4 pages, 5 figure

French Automobiles and the Chinese Boycotts of 2008: Politics Really Does Affect Commerce

We explore the economic impact of boycotts of French automobiles in China during the time of the 2008 Beijing Olympics. Conditions were favorable for a boycott, enabling Chinese consumers to overcome the collective action problems that can prevent boycott success and other voluntary contributions to public goods. We use brand and model level data in a difference-in-difference specification to investigate the boycotts’ effects on sales. A robust pattern of large impacts emerges: sales of French automobile brands fell 25-33% or more. Consumers substituted mostly toward Chinese and other Asian cars. The sales of the French models did not experience similar relative sales declines in countries other than China—triple-difference estimates point toward even larger relative loss of market share in China. Our results provide evidence that commerce can be used as an effective political weapon

A role of corazonin receptor in larval-pupal transition and pupariation in the oriental fruit fly Bactrocera dorsalis (Hendel) (Diptera: Tephritidae)

Corazonin (Crz) is a neuropeptide hormone, but also a neuropeptide modulator that is internally released within the CNS, and it has a widespread distribution in insects with diverse physiological functions. Here, we identified and cloned the cDNAs of Bactrocera dorsalis that encode Crz and its receptor CrzR. Mature BdCrz has 11 residues with a unique Ser11 substitution (instead of the typical Asn) and a His in the evolutionary variable position 7. The BdCrzR cDNA encodes a putative protein of 608 amino acids with 7 putative transmembrane domains, typical for the structure of G-protein-coupled receptors. When expressed in Chinese hamster ovary (CHO) cells, the BdCrzR exhibited a high sensitivity and selectivity for Crz (EC50 approximate to 52.5 nM). With qPCR, the developmental stage and tissue-specific expression profiles in B. dorsalis demonstrated that both BdCrz and BdCrzR were highly expressed in the larval stage, and BdCrzR peaked in 2-day-old 3rd-instar larvae, suggesting that the BdCrzR may play an important role in the larval-pupal transition behavior. Immunochemical localization confirmed the production of Crz in the central nervous system (CNS), specifically by a group of three neurons in the dorso-lateral protocerebrum and eight pairs of lateral neurons in the ventral nerve cord. qPCR analysis located the BdCrzR in both the CNS and epitracheal gland, containing the Inka cells. Importantly, dsRNA-BdCrzR-mediated gene-silencing caused a delay in larval-pupal transition and pupariation, and this phenomenon agreed with a delayed expression of tyrosine hydroxylase and dopa-decarboxylase genes. We speculate that CrzR-silencing blocked dopamine synthesis, resulting in the inhibition of pupariation and cuticular melanization. Finally, injection of Crz in head-ligated larvae could rescue the effects. These findings provide a new insight into the roles of Crz signaling pathway components in B. dorsalis and support an important role of CrzR in larval-pupal transition and pupariation behavior

Laves-phase evolution during aging in fine grained heat-affected zone of a tungsten-strengthened 9% Cr steel weldment

The precipitation and coarsening of Laves-phase in the fine grained heat-affected zone (FGHAZ) of a 9% Cr steel P92 welded joint during thermal aging at 923 K were investigated and compared to the base metal (BM), in order to clarify their effects on the Type IV fracture. Laves-phase precipitated mostly on the prior austenite grain boundaries of the FGHAZ. In comparison with BM, FGHAZ contained more grain boundary areas and can provide more nucleation sites for Laves-phase, resulting in an accelerated precipitation and rapidly reaching to the around 1.0% of saturated volume fraction. The coarsening of Laves-phase precipitates in FGHAZ was also much faster than that in BM, enhanced by the contribution of grain boundary diffusion resulted from its finer prior austenite grains. The FGHAZ had denser and smaller Laves-phase precipitates during the precipitation period in comparison with BM, obviously improved the creep strength by precipitation hardening. However, this effect in FGHAZ reduced sharply during coarsening owing to its coarsening rate greater than that of BM. In addition to the initial coarse polygonal subgrains with low dislocation density in FGHAZ produced by the weld thermal cycle and subsequent tempering in post-weld heat treatment (PWHT), coarse Laves-phase precipitates on grain boundaries formed in the long-term thermal aging, contributing to the formation of the creep cavities, can also play a key role in Type IV fracture of welded joint in 9% Cr steels

Observing white dwarf tidal stripping with TianQin gravitational wave observatory

Recently discovered regular X-ray bursts known as quasi-periodic eruptions have a proposed model that suggests a tidal stripping white dwarf inspiralling into the galaxy's central black hole on an eccentric orbit. According to this model, the interaction of the stripping white dwarf with the central black hole would emit gravitational wave signals as well, their detection can help explore the formation mechanism of quasi-periodic eruptions and facilitate multi-messenger observations. In this paper, we aim to perform a preliminary study of the gravitation wave observation of TianQin on this stripping white dwarf model. We investigated the horizon distance of TianQin on this type of gravitation wave signal and found it can be set to 200Mpc. We also find that those stripping white dwarf model sources with central black hole mass within $10^4\sim10^{5.5}M_\odot$ are more likely to be detected by TianQin. We assessed the parameter estimation precision of TianQin on those stripping white dwarf model sources. Our result shows that, even in the worst case, TianQin can determine the central black hole mass, the white dwarf mass, the central black hole spin, and the orbital initial eccentricity with a precision of $10^{-2}$. In the optimistic case, TianQin can determine the central black hole mass and the white dwarf mass with a precision of $10^{-7}$, determine the central black hole spin with a precision of $10^{-5}$, and determine the orbital initial eccentricity with a precision of $10^{-8}$. Moreover, TianQin can determine the luminosity distance with a precision of $10^{-1}$ and determine the sky localization with a precision of $10^{-2}\sim10$ $\rm deg^2$.Comment: 9 pages, 4 figure

Preparation and biological application of antibodies against leucoanthocyanidin reductase and anthocyanidin reductase from grape berry

Proanthocyanidins (PAs) endow wine with the flavor of bitterness and astringency. Both leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) are two key enzymes of PA biosynthesis in grape berries, but the previous studies on these enzymes only focused on the transcriptional expression of these genes. Here, the full-length cDNAs of VvLAR1, VvLAR2 and VvANR, respectively, were cloned from wine grape berries and were then introduced into the pGEX-4T-1 expression vectors, which were highly expressed in Escherichia coli DH5α cells with the induction of the isopropyl-β-D-thiogalactoside (IPTG). The purified fusion proteins were used as the antigens to immunize rabbits, separately. The obtained antiserums were further purified to obtain the immunoglobulin G (Ig G) fractions, which were demonstrated to be capable of specifically immuno-recognizing the VvLAR1, VvLAR2 and VvANR from the crude protein extracts from grape berries with weight masses of approximately 43 kD. The analyses of translational expression of these enzyme genes during berry development and immunohistochemical localization of these proteins, by using the obtained antibodies, showed that a high amount of VvLAR1, VvLAR2 or VvANR was present at the pre-veraison stage and these enzyme proteins were all localized on the outer layer of the berry skin and the vascular bundle, as well as in the inner layer of the seed coat. This work provides an important basis for further studies on PA biosynthesis in grape berries.

Scaling behaviour and memory in heart rate of healthy human

We investigate a set of complex heart rate time series from healthy human in different behaviour states with the detrended fluctuation analysis and diffusion entropy (DE) method. It is proposed that the scaling properties are influenced by behaviour states. The memory detected by DE exhibits an approximately same pattern after a detrending procedure. Both of them demonstrate the long-range strong correlations in heart rate. These findings may be helpful to understand the underlying dynamical evolution process in the heart rate control system, as well as to model the cardiac dynamic process

Identification and Characterization of a Novel Non-Coding RNA Involved in Sperm Maturation

A long and ever-expanding roster of small (∼20–30 nucleotides) RNAs has emerged during the last decade, and most can be subsumed under the three main headings of microRNAs(miRNAs), Piwi-interacting RNAs(piRNAs), and short interferingRNAs(siRNAs). Among the three categories, miRNAs is the most quickly expanded group. The most recent number of identified miRNAs is 16,772 (Sanger miRbase, April 2011). However, there are insufficient publications on their primary forms, and no tissue-specific small RNAs precursors have been reported in the epididymis. Here, we report the identification in rats of an epididymis-specific, chimeric, noncoding RNA that is spliced from two different chromosomes (chromosomes 5 and 19), which we named HongrES2. HongrES2 is a 1.6 kb mRNA-like precursor that gives rise to a new microRNA-like small RNA (mil-HongrES2) in rat epididymis. The generation of mil-HongrES2 is stimulated during epididymitis. An epididymis-specific carboxylesterase named CES7 had 100% cDNA sequence homology at the 3′end with HongrES2 and its protein product could be downregulated by HongrES2 via mil-HongrES2. This was confirmed in vivo by initiating mil-HongrES2 over-expression in rats and observing an effect on sperm capacitation