Free-flowing rivers (FFRs) support diverse, complex and dynamic ecosystems globally, providing important societal and economic services. Infrastructure development threatens the ecosystem processes, ...biodiversity and services that these rivers support. Here we assess the connectivity status of 12 million kilometres of rivers globally and identify those that remain free-flowing in their entire length. Only 37 per cent of rivers longer than 1,000 kilometres remain free-flowing over their entire length and 23 per cent flow uninterrupted to the ocean. Very long FFRs are largely restricted to remote regions of the Arctic and of the Amazon and Congo basins. In densely populated areas only few very long rivers remain free-flowing, such as the Irrawaddy and Salween. Dams and reservoirs and their up- and downstream propagation of fragmentation and flow regulation are the leading contributors to the loss of river connectivity. By applying a new method to quantify riverine connectivity and map FFRs, we provide a foundation for concerted global and national strategies to maintain or restore them.
Big data analysis, Internet technology, and cloud computing are being integrated to the allocation of production and manufacturing (P-M) resources, promoting the transformation, upgrading, and ...innovative development of traditional job-shop P-M resource allocation. However, the existing studies have not fully considered the demand dynamicity of production materials. To solve the problem, this paper attempts to predict the demand and optimize the allocation of job-shop P-M resources. Firstly, a demand prediction model was established for job-shop P-M resources, which can simultaneously capture the static and dynamic spatial dependence of P-M resource volume. Based on the demand prediction, the authors detailed an allocation optimization strategy for job-shop P-M resources, and defined the objective function and constraints. The proposed model was proved effective through experiments.
The microscopic understanding on the influence of the pairing correlations or the superfluidity on the nuclear chiral rotation has been a longstanding and challenging problem. Based on the ...three-dimensional cranking covariant density functional theory, a shell-model-like approach with exact particle number conservation is implemented to take into account the pairing correlations and applied for the chiral doublet bands built on the configuration πh11/22⊗νh11/2−1 in 135Nd. The data available, including the I−ω relation, as well as the electromagnetic transition probabilities B(M1) and B(E2), are well reproduced. It is found that the superfluidity can reduce the critical frequency and make the chiral rotation easier. The mechanism is that the particle/hole alignments along the short/long axis are reduced by the pairing correlations, resulting in the enhanced preference of the collective rotation along the intermediate axis, and inducing the early appearance of the chiral rotation.
Hepatitis E virus (HEV) is a zoonotic pathogen of which pigs are reservoirs. To determine the presence of HEV RNA in commercial pig livers sold in local grocery stores in the USA, 127 packages of ...commercial pig liver were purchased and tested by a universal RT-PCR assay capable of detecting all four known HEV genotypes. Among the 127 livers tested, 14 were positive for HEV RNA. Sequence and phylogenetic analyses revealed that the 14 isolates all belonged to genotype 3. An animal study was subsequently conducted in pigs to determine whether the PCR-positive pig livers still contained infectious virus. The results showed that pigs inoculated with two of the three PCR-positive pig-liver homogenates became infected, as evidenced by the detection of faecal virus shedding, viraemia and seroconversion. The data demonstrated that commercial pig livers sold in grocery stores are contaminated by HEV and that the contaminating virus remains infectious, thus raising a public-health concern for food-borne HEV infection.
HIAF (High Intensity heavy ion Accelerator Facility), a new facility planned in China for heavy ion related researches, consists of two ion sources, a high intensity Heavy Ion Superconducting Linac ...(HISCL), a 45 Tm Accumulation and Booster Ring (ABR-45) and a multifunction storage ring system. The key features of HIAF are unprecedented high pulse beam intensity and versatile operation mode. The HIAF project aims to expand nuclear and related researches into presently unreachable region and give scientists possibilities to conduct cutting-edge researches in these fields. The general description of the facility is given in this article with a focus on the accelerator design.
The neutrinoless double-β (0νββ) decay and the double Gamow-Teller (DGT) transition are investigated with the state-of-the-art Relativistic Configuration-interaction Density functional theory. A ...strong linear correlation between the nuclear matrix elements (NMEs) of the 0νββ decay and the DGT transition is demonstrated. This linear correlation is found to originate from the similarity of the leading-order term of the 0νββ-decay operator and the DGT-transition one, as revealed by expanding the 0νββ-decay operator in terms of the spherical harmonics. The present results provide a strong support to constrain the 0νββ-decay NMEs through the double charge-exchange reactions.
Cartilage in joints such as the hip and knee experiences repeated phases of heavy loading and low load recovery during the 24-h day/night cycle. Our previous work has shown 24 h rhythmic changes in ...gene expression at transcript level between night and day in wild type mouse cartilage which is lost in a circadian clock knock-out mouse model. However, it remains unknown to what extent circadian rhythms also regulate protein level gene expression in this matrix rich tissue.
We investigated daily changes of protein abundance in mouse femoral head articular cartilage by performing a 48-h time-series LC-MS/MS analysis.
Out of the 1,177 proteins we identified across all time points, 145 proteins showed rhythmic changes in their abundance within the femoral head cartilage. Among these were molecules that have been implicated in key cartilage functions, including CTGF, MATN1, PAI-1 and PLOD1 & 2. Pathway analysis revealed that protein synthesis, cytoskeleton and glucose metabolism exhibited time-of-day dependent functions. Analysis of published cartilage proteomics datasets revealed that a significant portion of rhythmic proteins were dysregulated in osteoarthritis and/or ageing.
Our circadian proteomics study reveals that articular cartilage is a much more dynamic tissue than previously thought, with chondrocytes driving circadian rhythms not only in gene transcription but also in protein abundance. Our results clearly call for the consideration of circadian timing mechanisms not only in cartilage biology, but also in the pathogenesis, treatment strategies and biomarker detection in osteoarthritis.
The wide band gap semiconductor Ga
2
O
3
has become an excellent UV detection material due to its suitable band gap, high crystalline quality and thermal stability. In this paper, the microstructure ...of Ga
2
O
3
with different thicknesses is characterized and the solar-blind detection performance of Ga
2
O
3
/p-Si heterojunctions are further investigated. XRD and UV–VIS demonstrate that Ga
2
O
3
sputtered for 20 min is amorphous with a band gap of 4.98 eV, as the sputtering time increases, Ga
2
O
3
grows along the (002) crystal plane and the band gap increases. XPS reveals that the lattice oxygen content in the Ga
2
O
3
increases with the sputtering time, however, the Ga
3+
content reaches a peak in Ga
2
O
3
sputtered for 1.5 h. And the increasing of the binding energy between Ga-O in Ga
2
O
3
/p-Si heterojunctions accelerates response speed. Electrical experiments show that the heterojunction consisting of sputtered 1.5 h Ga
2
O
3
and p-Si reaches a higher PDCR, with a value of 6684 at 5.7 V. Meanwhile, the rise and decay time of the heterojunction are 0.13 s and 0.14 s at 0 V, and the decay time gradually increases from 0.1 to 0.7 s with increasing the applied voltage. However, insertion of 20 nm Si-doped Ga
2
O
3
as a hole-blocking layer at the interface of p-Si and Ga
2
O
3
remarkably declines the decay time under various applied biases and causes no obvious damage to the photo current of the heterojunction.
The time-dependent covariant density functional theory in 3D lattice space has been developed and applied to investigate the microscopic dynamics of the linear-chain cluster states for carbon ...isotopes in the reactions 4He+8Be and 4He+10Be without any symmetry assumptions. By examining the density distribution and its time evolutions, the structure and dynamics of the linear-chain states are analyzed, and the quasiperiodic oscillations of the clusters are revealed. For 4He+8Be, the linear-chain states evolve to a triangular configuration and then to a more compact shape. In contrast, for 4He+10Be, the lifetime of the linear-chain states is much more prolonged due to the dynamical isospin effects by the valence neutrons which slow down the longitudinal oscillations of the clusters and persist the linear-chain states. The dependence of the linear chain survival time and dynamical isospin effects on impact parameters have been illustrated as well.
The mechanical response of amorphous silica (or silica glass) under hydrostatic compression for very high pressures up to 25GPa is modelled via an elastic–plastic constitutive equation (continuum ...mechanics framework). The material parameters appearing in the theory have been estimated from the ex situ experimental data of Rouxel et al. Rouxel T, Ji H, Guin JP, Augereau F, Rufflé B. J Appl Phys 2010;107(9):094903. The model is shown to capture the major features of the pressure–volume response changes from the in situ experimental work of Sato and Funamori Sato T, Funamori N. Phys Rev Lett 2008;101:255502 and Wakabayashi et al. Wakabayashi D, Funamori N, Sato T, Taniguchi T. Phys Rev B 2011;84(14):144103. In particular, the saturation of densification, the increase in elasticity parameters (bulk, shear and Young’s moduli) and Poisson’s ratio are found to be key parameters of the model.
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