This paper presents a numerical study on the flow around two tandem circular cylinders beneath a free surface at a Reynolds number of $180$. The free-surface effects on the wake dynamics and hydrodynamic forces are investigated through a parametric study, covering a parameter space of gap ratios from $0.20$ to $2.00$, spacing ratios from $1.50$ to $4.00$ and Froude numbers from $0.2$ to $0.8$. A jet-like flow accompanied by a shear layer of positive vorticity separating from the free surface is formed in the wake at small gap ratios, which significantly alters the wake pattern through its dynamic behaviours. At shallow submergence depths, the three-dimensional wake transitions from mode B to mode A as the distance between the cylinders increases. As submergence depth increases, the wavy deformation of the primary vortex cores disappears in the wake, and the flow transitions to a two-dimensional state. Higher Froude numbers can extend the effect of the free surface to deeper submergence depths. The critical spacing ratio tends to be larger at higher Froude numbers. Furthermore, the free-surface deformation is examined. The free-surface profile typically comprises a hydraulic jump immediately ahead of the upstream cylinder, trapped waves in the vicinity of the two tandem cylinders and well-defined travelling waves on the downstream side. The frequencies of the waves cluster around the vortex shedding frequency, indicating a close association between the generation of waves and the vortex shedding process.

This study proposes a novel super-resolution (or SR) framework for generating high-resolution turbulent boundary layer (TBL) flow from low-resolution inputs. The framework combines a super-resolution generative adversarial neural network (SRGAN) with down-sampling modules (DMs), integrating the residual of the continuity equation into the loss function. The DMs selectively filter out components with excessive energy dissipation in low-resolution fields prior to the super-resolution process. The framework iteratively applies the SRGAN and DM procedure to fully capture the energy cascade of multi-scale flow structures, collectively termed the SRGAN-based energy cascade reconstruction framework (EC-SRGAN). Despite being trained solely on turbulent channel flow data (via ‘zero-shot transfer’), EC-SRGAN exhibits remarkable generalization in predicting TBL small-scale velocity fields, accurately reproducing wavenumber spectra compared to direct numerical simulation (DNS) results. Furthermore, a super-resolution core is trained at a specific super-resolution ratio. By leveraging this pretrained super-resolution core, EC-SRGAN efficiently reconstructs TBL fields at multiple super-resolution ratios from various levels of low-resolution inputs, showcasing strong flexibility. By learning turbulent scale invariance, EC-SRGAN demonstrates robustness across different TBL datasets. These results underscore the potential of EC-SRGAN for generating and predicting wall turbulence with high flexibility, offering promising applications in addressing diverse TBL-related challenges.

This research communication reports the effects of a compound enzyme preparation consisting of fibrolytic (cellulase 3500 CU/g, xylanase 2000 XU/g, β-glucanase 17 500 GU/g) and amylolytic (amylase 37 000 AU/g) enzymes on nutrient intake, rumen fermentation, serum parameters and production performance in primiparous early-lactation (47 ± 2 d) dairy cows. Twenty Holstein–Friesian cows in similar body condition scores were randomly divided into control (CON, n = 10) and experimental (EXP, n = 10) groups in a completely randomized single-factor design. CON was fed a basal total mixed ration diet and EXP was dietary supplemented with compound enzyme preparation at 70 g/cow/d. The experiment lasted 4 weeks, with 3 weeks for adaptation and then 1 week for measurement. Enzyme supplementation significantly increased diet non-fibrous carbohydrates (NFC) content as well as dry matter intake (DMI) and NFC intake (P < 0.05). EXP had increased ruminal butyrate and isobutyrate percentages (P < 0.01) but decreased propionate and valerate percentages (P < 0.05), as well as increased serum alkaline phosphatase activity and albumin concentration (P ≤ 0.01). Additionally, EXP had increased milk yield (0.97 kg/d), 4% fat corrected milk yield and energy corrected milk yield, as well as milk fat and protein yield (P < 0.01). In conclusion, dietary supplementation with a fibrolytic and amylolytic compound enzyme preparation increased diet NFC content, DMI and NFC intake, affected rumen fermentation by increasing butyrate proportion at the expense of propionate, and enhanced milk performance in primiparous early-lactation dairy cows.

The laboratory generation and diagnosis of uniform near-critical-density (NCD) plasmas play critical roles in various studies and applications, such as fusion science, high energy density physics, astrophysics as well as relativistic electron beam generation. Here we successfully generated the quasistatic NCD plasma sample by heating a low-density tri-cellulose acetate (TCA) foam with the high-power-laser-driven hohlraum radiation. The temperature of the hohlraum is determined to be 20 eV by analyzing the spectra obtained with the transmission grating spectrometer. The single-order diffraction grating was employed to eliminate the high-order disturbance. The temperature of the heated foam is determined to be T = 16.8 ± 1.1 eV by analyzing the high-resolution spectra obtained with a flat-field grating spectrometer. The electron density of the heated foam is about $N_e=4.0\pm 0.3\times {10}^{20}{\text{cm}}^{-3}$ under the reasonable assumption of constant mass density.

The formation of manganese (Mn) oxides is influenced by environmental conditions and, in some red soils, Mn oxides occur as coatings on the surface of kaolinite particles in the form of colloidal films or fine particles. The present study aimed to explore the types of formation mechanisms of Mn oxide minerals on the surface of kaolinite. Mn oxide minerals synthesized by reducing the Mn in KMnO4 with a divalent Mn salt (MnSO4) were examined using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effects of various initial molar ratios of Mn2+/Mn7+ (R = 1:0.67, 1:1, 1:2, and 1:4), cationic species (Na+ or Mg2+), synthesis temperatures (30, 60, and 110°C), and amount of added kaolinite (0.25, 0.5, 1.0, 2.0, and 5.0 g) on the formation of Mn oxides were studied. The results showed that Mn oxide mineral types were affected by the initial R value and the background cation. With decreases in the initial R value, the synthesized minerals transformed from cryptomelane to birnessite. The relative mass ratios of kaolinite to Mn oxide were calculated as 1:0.92, 1:0.63, 1:1.15, and 1:1.63. The sodium cation (Na+) had a greater role than Mg2+ in promoting the dissolution–recrystallization of birnessite to cryptomelane. The synthesis temperature had no effect on mineral types, but Mn content increased as temperature increased. When the amount of added kaolinite was increased from 0.25 to 5.0 g, Mn oxide minerals formed gradually and transformed from birnessite to cryptomelane. This work revealed a possible formation process and reaction mechanism on the surface of kaolinite particles in some red soils.

Chemosensory proteins (CSPs) were necessary for insect sensory system to perform important processes such as feeding, mating, spawning, and avoiding natural enemies. However, their functions in non-olfactory organs have been poorly studied. To clarify the function of CSPs in the development of Mythimna separata (Walker) larvae, two CSP genes, MsCSP17 and MsCSP18, were identified from larval integument transcriptome dataset. Both of MsCSP17 and MsCSP18 contained four conserved cysteine sites (C × (6)-C × (18)-C × (2)-C), with a signal peptide at the N-terminal. RT-qPCR analysis showed that MsCSP17 and MsCSP18 have different expression patterns among different developmental stages and tissues. MsCSP17 was highly expressed in 1st–4th instar larvae, and MsCSP18 had high expression in adults. Both genes were expressed highly in larval head, thorax, integument and mandible. Moreover, both of MsCSP17 and MsCSP18 were lowly expressed in larval integuments when larvae molted for 6 h and 9 h from 3rd to 4th instar, but highly at the beginning and end phase during molting. After injection of dsMsCSP17 and dsMsCSP18, the expression levels of two genes decreased significantly, with the body weight of larvae decreased, the mortality increased, and the eclosion rate decreased. It was suggested that MsCSP17 and MsCSP18 contributed to the development of M. separata larvae.

Sporadic clusters of healthcare-associated coronavirus disease 2019 (COVID-19) occurred despite intense rostered routine surveillance and a highly vaccinated healthcare worker (HCW) population, during a community surge of the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) B.1.617.2 δ (delta) variant. Genomic analysis facilitated timely cluster detection and uncovered additional linkages via HCWs moving between clinical areas and among HCWs sharing a common lunch area, enabling early intervention.

This study topologically describes near-wall flows around a surface-mounted cylinder at a high Reynolds number ($Re$) of $5\times 10^4$ and in a very thick boundary layer, which were partially measured or technically approximated from the literature. For complete and rational flow construction, we use high-resolution simulations and critical-point theory. The large-scale near-wake vortex is composed of two connected segments rolled up from the sides of the cylinder and from the free end. Another large-scale side vortex clearly roots on two notable foci on the lower side wall. In the junction region, the side vortex moves upwards with a curved trajectory, which induces the formation of nodes on the ground surface. In the free-end region, the side vortex is compressed, which results in a smaller trailing-edge vortex and its downstream movement. Only tip vortices are observed in the far wake. The origin of the tip vortices and their distinction from the near-wake vortex are discussed. Further analyses suggest that $Re$ independence should be treated with high caution when $Re$ increases from 500 to ${O}(10^4)$. The occurrence of upwash flow behind the cylinder strongly depends on the increase in $Re$, the mechanism of which is also provided. The separation–reattachment process in the junction region and the trailing-edge vortices are discovered only at a high $Re$. The former should significantly affect the strength of the side vortex in the junction region and the latter should cause a sharp drop in pressure near the trailing edge.

South-east Asia's diverse coastal wetlands, which span natural mudflats and mangroves to man-made salt pans, offer critical habitat for many migratory waterbird species in the East Asian–Australasian Flyway. Species dependent on these wetlands include nearly the entire population of the Critically Endangered spoon-billed sandpiper Calidris pygmaea and the Endangered spotted greenshank Tringa guttifer, and significant populations of several other globally threatened and declining species. Presently, more than 50 coastal Important Bird and Biodiversity Areas (IBAs) in the region (7.4% of all South-east Asian IBAs) support at least one threatened migratory species. However, recent studies continue to reveal major knowledge gaps on the distribution of migratory waterbirds and important wetland sites along South-east Asia's vast coastline, including undiscovered and potential IBAs. Alongside this, there are critical gaps in the representation of coastal wetlands across the protected area networks of many countries in this region (e.g. Viet Nam, Indonesia, Malaysia), hindering effective conservation. Although a better understanding of the value of coastal wetlands to people and their importance to migratory species is necessary, governments and other stakeholders need to do more to strengthen the conservation of these ecosystems by improving protected area coverage, habitat restoration, and coastal governance and management. This must be underpinned by the judicious use of evidence-based approaches, including satellite-tracking of migratory birds, ecological research and ground surveys.

We study the asymptotic behaviour of convective heat transfer for turbulent flows in high-porosity fluid-saturated media by two-dimensional high-resolution numerical simulation. The generalized Navier–Stokes equations for incompressible fluid flow and the heat transport equation in porous media at the representative element volume scale are solved by the lattice Boltzmann method, wherein the non-Darcian effects are taken into consideration. The asymptotic behaviour of the Nusselt number $N$ has been revealed for Rayleigh numbers $10^4\leq R\leq 10^{11}$ and Darcy numbers $10^{-6}\leq \xi \leq 10^6$: all the data for various Darcy numbers gradually collapse onto a unique line with increasing Rayleigh number. The asymptote can be well represented by $N=0.146\times R^{0.286}$ for $R>2\times 10^7$, which approaches the relationship for the Rayleigh–Bénard turbulent convection of free fluid flows. The transition can be characterized by a scaling analysis with $R^{}\xi ^{3/2}\sim 1$, below which, however, the data collapse onto the Darcy limit for porous media. The Reynolds number and the Nusselt number both increase with Darcy number above the onset of convection, whereas a premature saturation of the Nusselt number is observed in comparison with that of the Reynolds number. The counter-gradient heat transport by the large-scale flows is quantified, which compensates for the increase of the gradient heat transport with Darcy number. The heat transfer in high-porosity fluid-saturated media with a very small Darcy number $\xi \geq 10^{-6}$ can be comparable to that of free fluid flows for a sufficiently high Rayleigh number $R\geq 10^{11}$.

To investigate the effects of dietary fibre on follicular atresia in pigs fed a high-fat diet, we fed thirty-two prepubescent gilts a basal diet (CON) or a CON diet supplemented with 300 g/d dietary fibre (fibre), 240 g/d soya oil (SO) or both (fibre + SO). At the 19th day of the 4th oestrus cycle, gilts fed the SO diet showed 112 % more atretic follicles and greater expression of the apoptotic markers, Bax and caspase-3, and these effects were reversed by the fibre diet. The abundance of SCFA-producing microbes was decreased by the SO diet, but this effect was reversed by fibre treatment. Concentrations of serotonin and melatonin in the serum and follicular fluid were increased by the fibre diet. Overall, dietary fibre protected against high fat feeding-induced follicular atresia at least partly via gut microbiota-related serotonin–melatonin synthesis. These results provide insight into preventing negative effects on fertility in humans consuming a high-energy diet.

We aimed to evaluate the relationship of plasma Mg with the risk of new-onset hyperuricaemia and examine any possible effect modifiers in hypertensive patients. This is a post hoc analysis of the Uric acid (UA) Sub-study of the China Stroke Primary Prevention Trial (CSPPT). A total of 1685 participants were included in the present study. The main outcome was new-onset hyperuricaemia defined as a UA concentration ≥417 μmol/l in men or ≥357 μmol/l in women. The secondary outcome was a change in UA concentration defined as UA at the exit visit minus that at baseline. During a median follow-up duration of 4·3 years, new-onset hyperuricaemia occurred in 290 (17·2 %) participants. There was a significantly inverse relation of plasma Mg with the risk of new-onset hyperuricaemia (per sd increment; OR 0·85; 95 % CI 0·74, 0·99) and change in UA levels (per sd increment; β −3·96 μmol/l; 95 % CI −7·14, −0·79). Consistently, when plasma Mg was analysed as tertiles, a significantly lower risk of new-onset hyperuricaemia (OR 0·67; 95 % CI 0·48, 0·95) and less increase in UA levels (β −8·35 μmol/l; 95 % CI −16·12, −0·58) were found among participants in tertile 3 (≥885·5 μmol/l) compared with those in tertile 1 (<818·9 μmol/l). Similar trends were found in males and females. Higher plasma Mg levels were associated with a decreased risk of new-onset hyperuricaemia in hypertensive adults.

Geochronological, major and trace element, and Sr–Nd–Hf isotopic data are reported for the monzonitic rocks of the Fushan pluton in the Taihang Mountains, central North China Craton, in order to investigate their sources, petrogenesis and tectonic implications. Zircon U–Pb dating results reveal that the Fushan pluton was emplaced during the Early Cretaceous (∼126–124 Ma). The monzonites and quartz monzonites are mainly characterized by calc-alkaline and magnesian features and display light rare earth element (LREE) enrichment and flat heavy REE (HREE) patterns with slightly positive Eu anomalies. They have similar whole-rock initial 87Sr/86Sr ratios (0.70653–0.70819), εNd(t) values (−13.6 to −18.6) and zircon εHf(t) values (−21.8 to −17.3). The primary magma of the Fushan pluton was derived from the partial melting of a spinel-facies amphibole-bearing ancient enriched lithospheric mantle. The monzonitic rocks also have high Ba–Sr and low Y and Yb contents, with high Sr/Y and La/Yb ratios. These geochemical features of monzonitic rocks are not only inherited from the magma source but also significantly enhanced by crystal fractionation during magmatic evolution; e.g. hornblende fractionation increased the Ba–Sr concentrations and Sr/Y ratios. During the Early Cretaceous, the slab sinking and roll-back of the Palaeo-Pacific Plate could have created an ancient big mantle wedge beneath East Asia and induced a lithospheric extensional process in the central North China Craton within an intracontinental setting.

The present study was undertaken to investigate the antiparasitic activity of extracellular products of Streptomyces albus. Bioactivity-guided isolation of chloroform extracts affording a compound showing potent activity. The structure of the compound was elucidated as salinomycin (SAL) by EI-MS, 1H NMR and 13C NMR. In vitro test showed that SAL has potent anti-parasitic efficacy against theronts of Ichthyophthirius multifiliis with 10 min, 1, 2, 3 and 4 h (effective concentration) EC50 (95% confidence intervals) of 2.12 (2.22–2.02), 1.93 (1.98–1.88), 1.42 (1.47–1.37), 1.35 (1.41–1.31) and 1.11 (1.21–1.01) mg L−1. In vitro antiparasitic assays revealed that SAL could be 100% effective against I. multifiliis encysted tomonts at a concentration of 8.0 mg L−1. In vivo test demonstrated that the number of I. multifiliis trophonts on Erythroculter ilishaeformis treated with SAL was markedly lower than that of control group at 10 days after exposed to theronts (P < 0.05). In the control group, 80% mortality was observed owing to heavy I. multifiliis infection at 10 days. On the other hand, only 30.0% mortality was recorded in the group treated with 8.0 mg L−1 SAL. The median lethal dose (LD50) of SAL for E. ilishaeformis was 32.9 mg L−1.

Exchange rates influence a country's trading capability, foreign reserves and competitiveness. Recently, the exchange rate between the Chinese RMB and the U.S. dollar has been a contentious issue in both the United States and China. In this paper, we conduct a historical review of how the United States deployed negotiation strategies with China on the exchange rate issue and consider the degree to which it follows theoretical expectations. We then analyze the changing nature of the factors which shape exchange rate negotiations between the two nations in projecting alternative scenarios for the future of conflict resolution between the U.S. and China on this issue. We predict that the U.S. is likely to continue alternating between competition and collaboration, a negotiation cycle influenced by U.S. domestic politics, and China is less likely to continue with accommodation and compromise. The sequencing and timing of each nation's negotiation strategy will lead to widely divergent consequences for the management of exchange rates and the world economy.

For the first time, we estimated the population sizes of two swan species and four goose species from observations during the non-breeding period in East Asia. Based on combined counts from South Korea, Japan and China, we estimated the total abundance of these species as follows: 42,000–47,000 Whooper Swans Cygnus cygnus; 99,000–141,000 Tundra Swans C. columbianus bewickii; 56,000–98,000 Swan Geese Anser cygnoides; 157,000–194,000 Bean Geese A. fabalis; 231,000–283,000 Greater White-fronted Geese A. albifrons; and 14,000–19,000 Lesser White-fronted Geese A. erythropus. While the count data from Korea and Japan provide a good reflection of numbers present, there remain gaps in the coverage in China, which particularly affect the precision of the estimates for Bean, Greater and Lesser White-fronted Geese as well as Tundra Swans. Lack of subspecies distinction of Bean Geese in China until recently also limits our ability to determine the true status of A. f. middendorffii there, but all indications suggest this population numbers around 18,000 individuals and is in need of urgent attention. The small, highly concentrated and declining numbers of Lesser White-fronted Geese give concern for this species, as do the major declines in Greater White-fronted Geese in China (in contrast to numbers in Japan and Korea, considered to be a separate flyway). In the absence of any demographic data, it is impossible to interpret the causes of these changes in abundance. Improved monitoring, including demographic and tracking studies are required to provide the necessary information to retain populations in favourable conservation status.