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Domestic chickens (Gallus gallus domesticus) fulfill various roles ranging from food and entertainment to religion and ornamentation. To survey its genetic diversity and trace the history of domestication, we investigated a total of 4938 mitochondrial DNA (mtDNA) fragments including 2843 previously published and 2095 de novo units from 2044 domestic chickens and 51 red junglefowl (Gallus gallus). To obtain the highest possible level of molecular resolution, 50 representative samples were further selected for total mtDNA genome sequencing. A fine-gained mtDNA phylogeny was investigated by defining haplogroups A-I and W-Z. Common haplogroups A-G were shared by domestic chickens and red junglefowl. Rare haplogroups H-I and W-Z were specific to domestic chickens and red junglefowl, respectively. We re-evaluated the global mtDNA profiles of chickens. The geographic distribution for each of major haplogroups was examined. Our results revealed new complexities of history in chicken domestication because in the phylogeny lineages from the red junglefowl were mingled with those of the domestic chickens. Several local domestication events in South Asia, Southwest China and Southeast Asia were identified. The assessment of chicken mtDNA data also facilitated our understanding about the Austronesian settlement in the Pacific.

Indirect-drive double-shell implosions have been performed at 100 kJ laser facility in China. The system of differential equations for the unablated mass, the average implosion velocity, and the ablation front radius of an outer shell within an indirect-drive double-shell capsule during acceleraction and deceleraction phases has been proposed from conservation principles of hydrodynamics. In addition, corrected rocket model for the inner shell has been built; the radius and velocity of the outer surface of the inner shell, as well as the radius and velocity of the inner shell mass center, are solved and give simple expressions. These relations provide the maximum implosion velocity and remaining unablated mass in terms of the initial capsule and the radiation temperature. These results are compared with numerical simulations, and good agreements have been observed.

Markers of alleles for three physiological candidate genes for reproductive traits, growth hormone (GHR), gonadotropin-releasing hormone receptor (GNRHR) and neuropeptide Y (NPY) were assessed for the association with the total egg production, number of double-yolked eggs and age at first egg in a single generation of a broiler breeder ( Gallus gallus ) pedigree dam line. Single-nucleotide polymorphisms and deletions were detected in the GHR, GNRHR and NPY genes. Genotypes were identified using a PCR-RFLP assay. The frequency of restriction enzyme+/−alleles in the population was for GHR 0.68 ( Nsp I−) and 0.32 ( Nsp I+), for NPY 0.78 ( Dra I+) and 0.22 ( Dra I−) and for GNRHR 0.54 ( Bpu 1102I+) and 0.46 ( Bpu 1102I−). Trait data from a total of 772 hens in 67 sire families from one generation of the pedigree dam line were recorded. However, the analysis used only the offspring of heterozygous sires to reduce the influence of selection and genetic background ( n =33 sire families for GHR; n =14 sire families for NPY; n =36 sire families for GNRHR). A dominance effect of NPY on age at first egg and an additive effect of GNRHR on the number of double-yolked eggs were found ( P <0.05).

Bos frontalis is an enigmatic bovine species found in selected regions of Myanmar, Bangladesh, China, Thailand, Bhutan and India. Though there are conflicting hypotheses regarding its origin, the most widely held view is that Bos frontalis originated from direct domestication of Bos gaurus (gaur). To study this, we analysed mtDNA control region and cytochrome b gene sequences of 41 B. frontalis from China and India, together with the available sequences in the public databases. Bayesian inference revealed clustering of B. frontalis and B. gaurus sequences into two separate clades. Application of relaxed molecular clock to these clades shows that B. frontalis and B. gaurus diverge between 0.134 and 0.207 million years ago. This time estimate lies much outside the ∼10,000-year-old history of animal domestication. Based on this finding, we argue that B. frontalis should be treated as a separate species/sub-species and not merely a domestic form of B. gaurus. Our study also highlights the gene flow between domestic cattle and B. frontalis population.

The pathway involving the signalling protein p21 Ras propagates a range of extracellular signals from receptors on the cell membrane to the cytoplasm and nucleus 1 . The Ras proteins regulate many effectors, including members of the Raf family of protein kinases. Ras-dependent activation of Raf-1 at the plasma membrane involves phosphorylation events, protein–protein interactions and structural changes 2 , 3 , 4 , 5 , 6 , 7 , 8 . Phosphorylation of serine residues 338 or 339 in the catalytic domain of Raf-1 regulates its activation in response to Ras, Src and epidermal growth factor 9 , 10 . Here we show that the p21-activated protein kinase Pak3 phosphorylates Raf-1 on serine 338 in vitro and in vivo . The p21-activated protein kinases are regulated by the Rho-family GTPases Rac and Cdc42 ( ref. 11 ). Our results indicate that signal transduction through Raf-1 depends on both Ras and the activation of the Pak pathway. As guanine-nucleotide-exchange activity on Rac can be stimulated by a Ras-dependent phosphatidylinositol-3-OH kinase 12 , 13 , a mechanism could exist through which one Ras effector pathway can be influenced by another.

SG-II, a 8-beam Nd:glass laser with an output energy capability of 6kJ at 1.053μm, was built and direct-drive implosions were successfully performed early in 2000. Both exploding pusher and ablative targets were imploded using glass capsules with diameters of 200 and 500μm, and a wall thickness of about 1μm. The deuterium and tritium (DT) gas pressure filled in these capsules were 2.0 and 0.5MPa, respectively. Sophisticated diagnostics were deployed to measure laser absorption, hot electron temperature and fraction, thermal electron temperature, neutron yields, ion temperature, temporally resolved x-ray images, fuel areal density, alpha particle image, and so on. Significant results, such as neutron yields up to 4 × 109 for exploding pushers with 100-ps laser pulse irradiation and 6 × 108 for ablative targets with 1-ns pulses and clear x-ray images to see the compression process, were obtained. Numerical simulations were conducted to optimize target and laser parameter design and to duplicate the results afterwards with the specific shot parameters used in the experiment.

3D point data acquisition has become a practical approach for generating complex 3D shapes. Subsequent smoothing or denoising operations on these raw data sets are required before performing sophisticated modeling operations. Based on covariance analysis and constructed directional curvature, a new approach of anisotropic curvature flow is developed for filtering the point data set. By introducing a forcing term, a balanced flow equation is constructed, which allows the anisotropic diffusion flow to be restricted in the flow diffusion band of the original surface. Thus, the common problem of shape shrinkage that puzzles most current denoising approaches for point-sampled geometry is avoided. Applying dynamic balance techniques, the equation converges to the solution quickly with appealing physical interpretations. The algorithms operate directly on the discrete sample points, requiring no vertex connectivity information. They are shown to be computationally efficient, robust and simple to implement.

The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium 1 , which is assumed to dominate the total extragalactic dispersion. Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs 2 , in at least one case there is evidence for an extreme magneto-ionic local environment 3 , 4 and a compact persistent radio source 5 . Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately 903 − 111 + 72 parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies 2 , 6 , far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications. A repeating fast radio burst co-located with a persistent radio source and associated with a dwarf host galaxy of a high star-formation rate has been detected.

Although the same environmental regulations apply to all regions in China, legal enforcement can be different due to local economic development priorities. There is still a lack of knowledge about how regional disparities affect the operating performance results of the implementation of corporate environmental management practices, thus providing little information for foreign companies when they invest and develop their production base in China. To fill this research gap, this paper collects data from the Fortune 500 Chinese firms to investigate the moderating role of regional disparities in affecting the performance results of corporate environmental management efforts based on the institutional theory. The disclosed corporate environmental responsibility (CER) practices serve as proxy to represent corporate environmental management practices. Content analysis approach was applied to collect and analyze CER practices published in the corporate reports of Chinese manufacturers. The results show that CER has a positive impact on operating income, while regional disparities influence the relationship between CER and corporate operating income. Specifically, CER and operating income are positively related in Eastern China; on the contrary, they are negatively related in Western China. This paper adds to the body of knowledge about environmental discrepancies in the same emerging economy, and provides insights for systematic consideration in terms of the issues of government environmental regulations and corporate environmental strategies.