ABSTRACT
High time resolution and accuracy are of critical importance in the studies of timing analysis and time delay localization of gamma-ray bursts (GRBs), soft gamma-ray repeaters (SGRs) and ...pulsars. The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) consisting of two micro-satellites, GECAM-A and GECAM-B, launched on 2020 December 10, is aimed at monitoring and locating X-ray and GRBs all over the sky. To achieve its scientific goals, GECAM is designed to have the highest time resolution (0.1 $\mu {\rm s}$) among all GRB detectors ever flown. Here, we make a comprehensive time calibration campaign including both on-ground and on-orbit tests to derive not only the relative time accuracy of GECAM satellites and detectors, but also the absolute time accuracy of GECAM-B. Using the on-ground calibration with a $\rm ^{22}Na$ radioactive source, we find that the relative time accuracy between GECAM-A and GECAM-B is about 0.15 $\mu {\rm s}$ (1σ). To measure the relative time accuracy between all detectors of a single GECAM satellite, cosmic-ray events detected on orbit are utilized since they could produce many secondary particles simultaneously record by multiple detectors. We find that the relative time accuracy among all detectors onboard GECAM-B is about 0.12 $\mu {\rm s}$ (1σ). Finally, we use the novel Li-CCF method to perform the absolute time calibration with Crab pulsar and SGR J1935+2154, both of which were jointly observed by GECAM-B and Fermi/GBM, and obtain that the time difference between GECAM-B and Fermi/GBM is 3.06 ± 6.04 $\mu {\rm s}$ (1σ).
We show that parity-time (PT) symmetry can be spontaneously broken in the recently reported energy level attraction of magnons and cavity photons. In the PT-broken phase, the magnon and photon form a ...high-fidelity Bell state with maximum entanglement. This entanglement is steady and robust against the perturbation of the environment, which is in contrast to the general wisdom that expects instability of the hybridized state when the symmetry is broken. This anomaly is further understood by the compete of non-Hermitian evolution and particle number conservation of the hybrid system. As a comparison, neither PT-symmetry breaking nor steady magnon-photon entanglement is observed inside the normal level repulsion case. Our results may open an exciting window to utilize magnon-photon entanglement as a resource for quantum information science.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
This experiment was conducted to assess the comparative effects of dietary antibiotics and oregano essential oil (OEO) addition on growth performance, antioxidant status and intestinal health of ...broilers. A total of 384 one-day-old broilers were randomly allocated to 4 treatments with 6 replicates of 16 broilers each. The 4 treatments were: an antibiotic-free control diet (control), control + 20 mg/kg colistin sulfate and 20 mg/kg virginiamycin (antibiotics), control + 200 mg/kg natural oregano essential oil (NOEO), and control + 200 mg/kg synthetic oregano essential oil (SOEO). The experiment lasted for 42 d. Results showed that birds fed with OEO had greater (P < 0.05) average daily gain (ADG) and lower (P < 0.05) feed conversion ratio (FCR) than those fed with control diet during d 1 to 21. Besides, birds fed with NOEO had the greatest (P < 0.05) ADG in the four groups during d 22 to 42. The serum oxidative stress parameters showed that OEO improved (P < 0.05) the activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and glutathione reductase (GR) of birds on day 21 and the activity of total antioxidant capacity (T-AOC) of birds on d 42. Relative to control, NOEO increased (P < 0.05) the activity of T-AOC in jejunum and decreased (P < 0.05) the level of malondialdehyde (MDA) in serum and jejunum. Moreover, OEO supplementation increased (P < 0.05) the concentrations of sIgA in duodenum and jejunum, Lactobacillus and total anaerobes in cecum, as well as activities of trypsin, chymotrypsin, lipase and amylase in duodenum, but restrained (P < 0.05) the amount of Escherichia coli. The NOEO supplementation increased (P < 0.05) total anaerobes of broilers on d 42 and the villus height to crypt depth ratio (VH/CD) of ileum. These results suggest that OEO improved antioxidant status and intestinal health of broilers which contributed to the growth performance improvement of broilers. Dietary OEO supplementation can be a promising alternative to antibiotic growth promoters for improving poultry production.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•l-his and l-lys cause the transformation of secondary structures of porcine myosin.•R-SH and hydrophobic groups are exposed in the presence of l-his and l-lys.•l-his and l-lys increase the ...solubility of porcine myosin at all ionic strengths.•l-lys contributes more to solubility than l-his due to more loss of α-helix.
The influence of l-lys and l-his on the solubility, surface hydrophobicity, sulphydryl content and conformational characteristics of porcine myosin solubilised in high (0.6M), physiological (0.15M) and low (1mM) ionic strength solutions were explored. The solubility of myosin was increased in the presence of l-his and/or l-lys in all ionic strength solutions used. The presence of l-his and l-lys caused increases in the surface hydrophobicity and reactive sulphydryl content (p<0.05). Circular dichroism revealed a significant decrease of α-helical content with an increase of random coils, β-turns and β-sheets in the presence of l-his and/or l-lys. These results demonstrate that the introduction of l-lys and l-his causes the unfolding of myosin, resulting in loss of α-helical structure, which is followed by increases in random coils, β-turns and β-sheets, which exposes buried hydrophobic and sulphydryl groups to the myosin surface, ultimately increasing the solubility of porcine myosin.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a space‐borne instrument dedicated to monitoring high‐energy transients, including Terrestrial Gamma‐ray Flashes ...(TGFs) and Terrestrial Electron Beams (TEBs). We implemented a TGF/TEB search algorithm for GECAM, with which 147 bright TGFs, 2 typical TEBs and 2 special TEB‐like events are identified during an effective observation time of ∼9 months. We show that, with gamma‐ray and charged particle detectors, GECAM can effectively identify and distinguish TGFs and TEBs, and measure their temporal and spectral properties in detail. A very high TGF‐lightning association rate of ∼80% is obtained between GECAM and GLD360 in east Asia region.
Plain Language Summary
Terrestrial gamma‐ray flashes (TGFs) and Terrestrial Electron Beams (TEBs) represent the most energetic radioactive phenomena in the atmosphere of the Earth. They reflect a natural particle accelerator that can boost electrons up to at least several tens of mega electron volts and produce gamma‐ray radiation. With novel detection technologies, Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) is a new powerful instrument to observe TGFs and TEBs, as well as study their properties. For example, it is difficult for most space‐borne high‐energy instruments to distinguish between TGFs and TEBs. However, we show here that, with the joint observation of gamma‐ray and charged particle detectors, GECAM can effectively identify TGFs and TEBs. GECAM can also reveal their fine features in the light curves and spectra.
Key Points
During 9‐month observation, Gravitational‐wave high‐energy Electromagnetic Counterpart All‐sky Monitor (GECAM) has detected 147 bright Terrestrial Gamma‐ray Flashes (TGFs), 2 typical Terrestrial Electron Beams (TEBs), and 2 special TEB‐like events
With novel detector design, GECAM can effectively classify TGFs and TEBs, and reveal their fine temporal features
We obtained a very high TGF‐lightning association rate (∼80%) between GECAM and GLD360 in east Asia region
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Summary Cartilage defects (CDs) and the most common joint disease, osteoarthritis (OA), are characterized by degeneration of the articular cartilage that ultimately leads to joint destruction. ...Current treatment strategies are inadequate: none results in restoration of fully functional hyaline cartilage, for uncertain long-term prognosis. Tissue engineering of cartilage with auto-cartilage cells or appropriate mesenchymal stem cell (MSC)-derived cartilage cells is currently being investigated to search for new therapies. Platelet-rich plasma (PRP), an autologous source of factors obtained by centrifugation, possesses various functions. For culture of MSCs and cartilage cells, it might be substituted for fetal bovine serum (FBS) with high efficiency and safety. It enhances the regeneration of cartilage cells when added to cartilage tissue engineering constructs for repairing CDs and as regenerative injection therapy for OA. But challenges also remain. Some of the growth factors (GFs) present in PRP have negative effects on the OA joint. It is therefore unlikely that a mix of GFs some of which have negative effects in the OA joint, as present in PRP, will be of benefit in OA. Future directions of PRP application may concentrate on seeking an appropriate and innocuous agent like anti-VEGF antibody that can modulate and control the effect of PRP.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Elucidating the cellular organization of the cerebral cortex is critical for understanding brain structure and function. Using large-scale single-nucleus RNA sequencing and spatial transcriptomic ...analysis of 143 macaque cortical regions, we obtained a comprehensive atlas of 264 transcriptome-defined cortical cell types and mapped their spatial distribution across the entire cortex. We characterized the cortical layer and region preferences of glutamatergic, GABAergic, and non-neuronal cell types, as well as regional differences in cell-type composition and neighborhood complexity. Notably, we discovered a relationship between the regional distribution of various cell types and the region’s hierarchical level in the visual and somatosensory systems. Cross-species comparison of transcriptomic data from human, macaque, and mouse cortices further revealed primate-specific cell types that are enriched in layer 4, with their marker genes expressed in a region-dependent manner. Our data provide a cellular and molecular basis for understanding the evolution, development, aging, and pathogenesis of the primate brain.
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•A comprehensive cell-type taxonomy is constructed for the entire macaque cortex•Stereo-seq reveals the global distribution of 264 cell types and their marker genes•Regional density and composition of cell types are coupled with cortical hierarchy•Cross-species analysis revealed primate-specific cell types enriched in layer 4
A spatially resolved single-cell transcriptome atlas of macaque cortex is generated that reveals the organization and evolution of primate cortical regions.
The aim of this study was to characterize detailed interfacial microstructures and evaluate tensile properties of Al6061-to-Cu dissimilar welded joints via electromagnetic pulse welding (EMPW) at ...different discharge voltages. The EMPWed joints consisted of annular weld zone and central non-weld zone. The outer and inner regions of annular weld zone exhibited mainly diffusion bonding and mechanical interlocking, respectively, representing a well-bonded interface. Distinctive discontinuous “droplet-like” pseudo-eutectic (α-Al + Al2Cu) particles or patches were observed to eject in the adjacent transition region in the non-weld zone. The highly non-equilibrium eutectic-like liquid or slurry at the Al/Cu interface was formed due to the ultra-high strain rate experienced by the interface and the ensuing instant temperature rise beyond the eutectic temperature of Al–Cu system, when the high-velocity flyer Al sheet crashed into the fixed Cu sheet driven by the Lorentz force during EMPW. The interfacial diffusion layer was thin in the order of 1–2 μm. The higher the discharge voltage was, the more obvious the interfacial diffusion layer and mechanical interlocking were, with “wave-like” and “inverted hook-like” interfacial characteristics observed. While interfacial failure occurred during the tensile lap shear tests for the joints made at a discharge voltage of 12 kV, the failure loads were still significantly higher than those specified in the AWS D17.2 standard. The EMPWed joints made at 14 kV and 16 kV remained intact and only base metal failure occurred, with the tensile lap shear failure loads reaching over twice those specified in the AWS D17.2 standard. Thus the well-bonded robust Al/Cu dissimilar welds were successfully achieved via EMPW.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Low temperature is one of the important factors limiting wheat yield in cold regions. Expansins are nonenzymatic proteins that loosen cell walls and play important roles in diverse biological ...processes related to cell wall modification, including development and stress tolerance. Many studies have shown that expansins are involved in resistance to various abiotic stresses, such as heat and drought. However, the role of expansins in response to low‐temperature stress remains unclear.
Based on our previous transcriptome data of a winter wheat cultivar Dongnongdongmai 2 (DN2), we found that one of the expansin genes, TaEXPA8, was significantly induced by low temperature, indicating a role for TaEXPA8 in cold resistance. In this study, the paralogous TaEXPA8 genes TaEXPA8‐A, TaEXPA8‐B and TaEXPA8‐D were cloned by RT‐PCR. These three genes were then transformed into Arabidopsis by the floral dip method. Expression patterns of TaEXPA8 genes in different tissues and in response to several abiotic stresses and hormones were detected by quantitative real‐time PCR (qRT‐PCR).
The results showed that TaEXPA8‐A and TaEXPA8‐B were expressed mainly in roots, while TaEXPA8‐D was expressed predominantly in flowers. TaEXPA8 genes were induced by low‐temperature and drought. The overexpression of TaEXPA8‐B and TaEXPA8‐D enhanced low‐temperature resistance and had increased superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activity and soluble protein, MDA and proline content.
In summary, our study suggested that the expansins TaEXPA8‐B and TaEXPA8‐D are involved in the response to low temperature and possibly play a role in cold resistance by activating the protective enzyme system.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Summary Currently, osteoarthritis (OA) is considered a disease of the entire joint, which is not simply a process of wear and tear but rather abnormal remodelling and joint failure of an organ. The ...bone–cartilage interface is therefore a functioning synergistic unit, with a close physical association between subchondral bone and cartilage suggesting the existence of biochemical and molecular crosstalk across the OA interface. The crosstalk at the bone–cartilage interface may be elevated in OA in vivo and in vitro . Increased vascularisation and formation of microcracks associated with abnormal bone remodelling in joints during OA facilitate molecular transport from cartilage to bone and vice versa . Recent reports suggest that several critical signalling pathways and biological factors are key regulators and activate cellular and molecular processes in crosstalk among joint compartments. Therapeutic interventions including angiogenesis inhibitors, agonists/antagonists of molecules and drugs targeting bone remodelling are potential candidates for this interaction. This review summarised the premise for the presence of crosstalk in bone–cartilage interface as well as the current knowledge of the major signalling pathways and molecular interactions that regulate OA progression. A better understanding of crosstalk in bone–cartilage interface may lead to development of more effective strategies for treating OA patients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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