BmNPV p35 regulates apoptosis in Bombyx mori via a novel target of interaction with the BmVDAC2-BmRACK1 complex

Voltage-dependent anion channel 2 (VDAC2) is an important channel protein that plays a crucial role in the host response to viral infection. The receptor for activated C kinase 1 (RACK1) is also a key host factor involved in viral replication. Our previous research revealed that Bombyx mori VDAC2 (BmVDAC2) and B. mori RACK1 (BmRACK1) may interact with Bombyx mori nucleopolyhedrovirus (BmNPV), though the specific molecular mechanism remains unclear. In this study, the interaction between BmVDAC2 and BmRACK1 in the mitochondria was determined by various methods. We found that BmNPV p35 interacts directly with BmVDAC2 rather than BmRACK1. BmNPV infection significantly reduced the expression of BmVDAC2, and activated the mitochondrial apoptosis pathway. Overexpression of BmVDAC2 in BmN cells inhibited BmNPV-induced cytochrome c (cyto c) release, decrease in mitochondrial membrane potential as well as apoptosis. Additionally, the inhibition of cyto c release by BmVDAC2 requires the involvement of BmRACK1 and protein kinase C. Interestingly, overexpression of p35 inhibited cyto c release during mitochondrial apoptosis in a RACK1 and VDAC2-dependent manner. Even the mutant p35, which loses Caspase inhibitory activity, could still bind to VDAC2 and inhibit cyto c release. In summary, our results indicated that BmNPV p35 interacts with the VDAC2-RACK1 complex to regulate apoptosis by inhibiting cyto c release. These findings confirm the interaction between BmVDAC2 and BmRACK1, the interaction between p35 and the VDAC2-RACK1 complex, and a novel target that BmNPV p35 regulates apoptosis in Bombyx mori via interaction with the BmVDAC2-BmRACK1 complex. The result provide an initial exploration of the function of this interaction in the BmNPV-induced mitochondrial apoptosis pathway.

Computational modeling of Chlamydomonas reinhardtii cellular radiation properties with synergistic consideration of complex structures and compositions

The radiation characteristics of microalgae are of great significance for the design of photobioreactors and ocean optical remote sensing. Yet the complex structure of microalgae makes it difficult to theoretically predict its radiation characteristics based on traditional Mie theory. In this work, taking Chlamydomonas reinhardtii as an example, a multi-component cell model with a complex structure is proposed, which considers the organelles and shape of microalgae, and the volume change during the production of Chlamydomonas reinhardtii lipids. The theoretical calculation is carried out using the discrete dipole approximation method, and an improved transmission method is used for experimental measurement. The experimental data are compared and analyzed with the multi-component complex structure model, the homogeneous sphere model and the coated sphere model. The results show that the calculation accuracy of the multi-component complex structure model is higher, the error of the scattering cross-section is reduced by more than 8.6% compared with the homogeneous sphere model and coated sphere model, and the absorption cross-section and the scattering phase function are in good agreement with the experimental results. With the increase of lipids, the absorption cross-section and the scattering phase function vary slightly. However, the scattering cross-section has an observed change with increasing wavelength. In addition, the theoretical calculation error can be reduced when the influence of the culture medium is taken into account.

Effects of temperature and charged vacancies on electronic and optical properties of β-Ga2O3 after radiation damage

β-Ga2O3 as an ultra-wide bandgap material is widely used in space missions and nuclear reactor environments. It is well established that the physical properties of β-Ga2O3 would be affected by radiation damage and temperature in such application scenarios. Defects are inevitably created in β-Ga2O3 upon irradiation and their dynamic evolution is positively correlated with the thermal motion of atoms as temperature increases. This work utilizes first-principles calculations to investigate how temperature influences the electronic and optical properties of β-Ga2O3 after radiation damage. It finds that the effect of p-type defects caused by Ga vacancies on optical absorption diminishes as temperature increases. The high temperature amplifies the effect of oxygen vacancies to β-Ga2O3, however, making n-type defects more pronounced and accompanied by an increase in the absorption peak in the visible band. The self-compensation effect varies when β-Ga2O3 contains both Ga vacancies and O vacancies at different temperatures. Moreover, in the case of Ga3- (O2+) vacancies, the main characters of p(n)-type defects caused by uncharged Ga0 (O0) vacancies disappear. This work aims to understand the evolution of physical properties of β-Ga2O3 under irradiation especially at high temperatures, and help analyze the damage mechanism in β-Ga2O3-based devices.

Copper Site Motion Promotes Catalytic NOx Reduction under Zeolite Confinement

Ammonia-mediated selective catalytic reduction (NH3-SCR) is currently the key approach to abate nitrogen oxides (NOx) emitted from heavy-duty lean-burn vehicles. The state-of-art NH3-SCR catalysts, namely, copper ion-exchanged chabazite (Cu-CHA) zeolites, perform rather poorly at low temperatures (below 200 °C) and are thus incapable of eliminating effectively NOx emissions under cold-start conditions. Here, we demonstrate a significant promotion of low-temperature NOx reduction by reinforcing the dynamic motion of zeolite-confined Cu sites during NH3-SCR. Combining complex impedance-based in situ spectroscopy (IS) and extended density-functional tight-binding molecular dynamics simulation, we revealed an environment- and temperature-dependent nature of the dynamic Cu motion within the zeolite lattice. Further coupling in situ IS with infrared spectroscopy allows us to unravel the critical role of monovalent Cu in the overall Cu mobility at a molecular level. Based on these mechanistic understandings, we elicit a boost of NOx reduction below 200 °C by reinforcing the dynamic Cu motion in various Cu-zeolites (Cu-CHA, Cu-ZSM-5, Cu-Beta, etc.) via facile postsynthesis treatments, either in a reductive mixture at low temperatures (below 250 °C) or in a nonoxidative atmosphere at high temperatures (above 450 °C).

Thermal transport across TiO2-H2O interface involving water dissociation: Ab initio-assisted deep potential molecular dynamics

Water dissociation on TiO2 surfaces has been known for decades and holds great potential in various applications, many of which require a proper understanding of thermal transport across the TiO2-H2O interface. Molecular dynamics (MD) simulations play an important role in characterizing complex systems' interfacial thermal transport properties. Nevertheless, due to the imprecision of empirical force field potentials, the interfacial thermal transport mechanism involving water dissociation remains to be determined. To cope with this, a deep potential (DP) model is formulated through the utilization of ab initio datasets. This model successfully simulates interfacial thermal transport accompanied by water dissociation on the TiO2 surfaces. The trained DP achieves a total energy accuracy of ∼238.8 meV and a force accuracy of ∼197.05 meV/Å. The DPMD simulations show that water dissociation induces the formation of hydrogen bonding networks and molecular bridges. Structural modifications further affect interfacial thermal transport. The interfacial thermal conductance estimated by DP is ∼8.54 × 109 W/m2 K, smaller than ∼13.17 × 109 W/m2 K by empirical potentials. The vibrational density of states (VDOS) quantifies the differences between the DP model and empirical potentials. Notably, the VDOS disparity between the adsorbed hydrogen atoms and normal hydrogen atoms demonstrates the influence of water dissociation on heat transfer processes. This work aims to understand the effect of water dissociation on thermal transport at the TiO2-H2O interface. The findings will provide valuable guidance for the thermal management of photocatalytic devices.

Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

Erratum: Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande [Phys. Rev. Lett. 130, 031802 (2023)]

This corrects the article DOI: 10.1103/PhysRevLett.130.031802.

[MRI evaluation of condylar bone regeneration after temporomandibular joint disc reduction and suture and analysis of factors affecting bone regeneration]

Objective: To evaluate the MRI manifestations of condylar bone regeneration after disc reduction and suture for anterior disc displacement without reduction (ADDWoR) patients and to analyze the relevant factors affecting bone regeneration. Methods: A total of 61 patients of 75 joints with ADDWoR who attended the Department of Maxillofacial Surgery of the Affiliated Hospital of Stomatology of Nanjing Medical University from April 2020 to December 2021 were enrolled in the study. The characteristics of MRI condylar bone regeneration were analyzed before and after surgery (follow-up for 6 months or more), and logistic regression analysis was performed on the influencing factors of bone regeneration. Results: The new bone formation of the condyle was found in 28 patients, with age of (20.2±4.9) years. However, there were 33 patients that had no condylar bone regeneration, with age of (41.9±17.5) years. A total of 35 joints in this study were found new bone formation. There were 16 joints (45.7%) had new bone formation on the posterior slope of the condyle, 10 joints (28.6%) around the condyle, 6 joints (17.1%) on the anterior slope of the condyle, and only 3 joints (8.6%) on the top of the condyle. Multivariate logistic regression analysis showed that age, preoperative disc length and degree of condylar bone resorption correlated with postoperative condylar bone regeneration(P<0.05). Patients younger than 30 years with non-shortened preoperative disc length and less condylar bone resorption have a higher probability of new bone formation. Conclusions: The condyle has bone regeneration capacity after correcting the abnormal relationship between disc and condyle, and young age, non-shortened preoperative disc length and less condylar bone resorption are conducive to postoperative condylar bone regeneration.

Revealing the Formation and Reactivity of Cage-Confined Cu Pairs in Catalytic NOx Reduction over Cu-SSZ-13 Zeolites by In Situ UV-Vis Spectroscopy and Time-Dependent DFT Calculation

The low-temperature mechanism of chabazite-type small-pore Cu-SSZ-13 zeolite, a state-of-the-art catalyst for ammonia-assisted selective reduction (NH3-SCR) of toxic NOx pollutants from heavy-duty vehicles, remains a debate and needs to be clarified for further improvement of NH3-SCR performance. In this study, we established experimental protocols to follow the dynamic redox cycling (i.e., CuII ↔ CuI) of Cu sites in Cu-SSZ-13 during low-temperature NH3-SCR catalysis by in situ ultraviolet-visible spectroscopy and in situ infrared spectroscopy. Further integrating the in situ spectroscopic observations with time-dependent density functional theory calculations allows us to identify two cage-confined transient states, namely, the O2-bridged Cu dimers (i.e., μ-η2:η2-peroxodiamino dicopper) and the proximately paired, chemically nonbonded CuI(NH3)2 sites, and to confirm the CuI(NH3)2 pair as a precursor to the O2-bridged Cu dimer. Comparative transient experiments reveal a particularly high reactivity of the CuI(NH3)2 pairs for NO-to-N2 reduction at low temperatures. Our study demonstrates direct experimental evidence for the transient formation and high reactivity of proximately paired CuI sites under zeolite confinement and provides new insights into the monomeric-to-dimeric Cu transformation for completing the Cu redox cycle in low-temperature NH3-SCR catalysis over Cu-SSZ-13.

First-principles study of thermal transport properties in ferroelectric HfO2 and related fluorite-structure ferroelectrics

The discovery of ferroelectricity in the fluorite-structure HfO₂ has attracted much interest in various applications including electro-optic devices and nonvolatile memories. Doping and alloying not only induce ferroelectricity in HfO₂, but also significantly impact the thermal conduction which plays an essential role in the heat dissipation and thermal stability of ferroelectric devices. To understand and regulate the heat transfer in ferroelectric HfO₂, it is crucial to investigate the thermal conduction properties of related fluorite-structure ferroelectrics so as to establish the structure-property relationship. In this work, using first-principles calculations, we investigate the thermal transport in twelve fluorite-structure ferroelectrics. We find an overall satisfactory agreement between the calculated thermal conductivities and those predicted by the simple theory of Slack. Among the family of fluorite-structure ferroelectrics, the transition-metal oxides HfO₂ and ZrO₂ have the highest thermal conductivities due to the strong interatomic bonding. We demonstrate that the spontaneous polarization, a feature specific to ferroelectrics, is positively correlated with the thermal conductivity, namely, the larger the spontaneous polarization, the larger the thermal conductivity. This is of chemical origin, namely, both the spontaneous polarization and the thermal conductivity are positively correlated to the "ionicity" of the ferroelectrics. We further find that the thermal conductivity is several times lower in the ferroelectric solid solution Hf_1-xZr_xO₂ than in its pure counterparts, especially in the thin films where the finite size effect further suppresses thermal conduction. Our findings suggest the spontaneous polarization as a specific criterion for identifying ferroelectrics with desired thermal conductivities, which may promote the design and application of ferroelectrics.

[Spatial and temporal distribution characteristics of seasonal A(H3N2) influenza in China, 2014-2019]

Objective: To analyze the spatial and temporal distribution characteristics of seasonal A(H3N2) influenza [influenza A(H3N2)] in China and to provide a reference for scientific prevention and control. Methods: The influenza A(H3N2) surveillance data in 2014-2019 was derived from China Influenza Surveillance Information System. A line chart described the epidemic trend analyzed and plotted. Spatial autocorrelation analysis was conducted using ArcGIS 10.7, and spatiotemporal scanning analysis was conducted using SaTScan 10.1. Results: A total of 2 603 209 influenza-like case sample specimens were detected from March 31, 2014, to March 31, 2019, and the influenza A(H3N2) positive rate was 5.96%(155 259/2 603 209). The positive rate of influenza A(H3N2) was statistically significant in the north and southern provinces in each surveillance year (all P<0.05). The high incidence seasons of influenza A (H3N2) were in winter in northern provinces and summer or winter in southern provinces. Influenza A (H3N2) clustered in 31 provinces in 2014-2015 and 2016-2017. High-high clusters were distributed in eight provinces, including Beijing, Tianjin, Hebei, Shandong, Shanxi, Henan, Shaanxi, and Ningxia Hui Autonomous Region in 2014-2015, and high-high clusters were distributed in five provinces including Shanxi, Shandong, Henan, Anhui, and Shanghai in 2016-2017. Spatiotemporal scanning analysis from 2014 to 2019 showed that Shandong and its surrounding twelve provinces clustered from November 2016 to February 2017 (RR=3.59, LLR=9 875.74, P<0.001). Conclusion: Influenza A (H3N2) has high incidence seasons with northern provinces in winter and southern provinces in summer or winter and obvious spatial and temporal clustering characteristics in China from 2014-2019.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

RNA methyltransferase BmMettl3 and BmMettl14 in silkworm (Bombyx mori) and the regulation of silkworm embryonic development

N6-methyladenosine (m6A) is a ubiquitous reversible epigenetic RNA modification that plays an important role in regulating many biological processes, especially embryonic development. However, regulation of m6A methylation during silkworm embryonic development and diapause remains to be investigated. In this study, we analyzed the phylogeny of subunits of methyltransferases BmMettl3 and BmMettl14, and detected the expression patterns of BmMettl3 and BmMettl14 in different tissues and at different developmental stages in silkworm. To investigate the function of m6A on the development of silkworm embryo, we analyzed the m6A/A ratio in diapause and diapause termination eggs. The results showed that BmMettl3 and BmMettl14 were highly expressed in gonads and eggs. Moreover, the expression of BmMettl3 and BmMettl14 and the m6A/A ratio were significantly increased in diapause termination eggs compared with diapause eggs in the early stage of silkworm embryonic development. Furthermore, in BmN cell cycle experiments, the percentage of cells in the S phase increased when lacking BmMettl3 or BmMettl14. This work contributes to understanding the role of m6A methylation during insect embryogenesis and gametogenesis. It also provides a research orientation to further analyze the role of m6A methylation in diapause initiation and termination during insect embryonic development.

Prediction of radiative properties of spherical microalgae considering internal heterogeneity and optical constants of various components

Most of the current predictions of the radiative properties of microalgae use the homogeneous sphere approximation based on the Mie scattering theory, and the refractive indices of the model were regarded as fixed values. Using the recently measured optical constants of various microalgae components, we propose a spherical heterogeneous model for spherical microalgae. The optical constants of the heterogeneous model were characterized by the measured optical constants of microalgae components for the first time. The radiative properties of the heterogeneous sphere were calculated using the T-matrix method and were well verified by measurements. It shows that the internal microstructure has a more significant effect on scattering cross-section and scattering phase function than absorption cross-section. Compared with the traditional homogeneous models selected with fixed values as refractive index, the calculation accuracy of scattering cross-section of the heterogeneous model improved by 15%-150%. The scattering phase function of the heterogeneous sphere approximation agreed better with measurements than the homogeneous models due to the more detailed description of the internal microstructure. It can be concluded that considering the internal microstructure of microalgae and characterizing the microstructure of the model by the optical constants of the microalgae components helps to reduce the error caused by the simplification of the actual cell.

Simulating nitrogen balance in Canadian agricultural soils from 1981 to 2016

Agriculture produces food, fiber and biofuels for the world's growing population, however, agriculture can be a major contributor of nitrogen (N) losses including emissions of ammonia (NH₃), nitrous oxide (N₂O) and nitrate (NO₃^-) leaching and runoff. A Canadian Agricultural Nitrogen Budget for Reactive N (CANBNr) model was developed to estimate the soil N balance in 3487 soil landscape of Canada polygons from 1981 to 2016. The CANBNr model integrates NH₃ emission from fertilizers, manure from housing, storage and field, as well as direct/indirect N₂O emissions from fertilizers, manures, crop residues and soil organic matter. The NO₃^- leaching is estimated based on the residual soil N (RSN) at harvest and drainage derived with the DeNitrification-DeComposition (DNDC) model. From 1981 to 2016, the N input from fertilizer and N fixation increased at a greater rate than N removal in harvested crops in all provinces of Canada, resulting in an increase in the RSN and N losses. In 2016, the Prairie provinces had lower N losses (11.7 kg N ha^-1) from N₂O, NH₃ and NO₃^- compared with 43.2 kg N ha^-1 in central Canada, and 76.5 kg N ha^-1 in Atlantic Canada. However, the Prairie provinces had 84.3% of the total Canadian farmland (74.3% of the total Canadian N input), while central Canada had 12.9% of Canadian farmland (21.7% of the total Canadian N input). In the Prairie provinces, the total N₂O loss from fertilizer N ranged 4.4-8.6 Gg N whereas NH₃ loss ranged from 17.1 to 44.6 Gg N and these values were influenced by both emission intensity and total land area. Total N₂O losses from manure were highest in Alberta, Ontario and Quebec resulting in 4.8, 4.4, and 3.4 Gg N and NH₃ losses from manure were also highest in these 3 provinces at 61.1, 45.2 and 40.4 Gg N, respectively. Nitrate leaching was impacted by drainage volumes, soil type and N inputs. In the non-growing season, NO₃^- leaching losses (36-yr average) were 63.3 Gg in Ontario and 57.5 Gg N in Quebec compared with 20.8 Gg N for Ontario and 35.5 Gg N for Quebec in the growing season. In contrast, the Prairie provinces showed higher NO₃^- leaching in the growing season (23.1-37.4 Gg N) than in the non-growing season (10.4-13.7 Gg N). In summary, total fertilizer N increased the most over the 36 years in the Prairies which resulted in increased RSN and N leaching losses that will require further intervention.

[Phenotype-genotype analysis of the autosomal recessive hereditary hearing loss caused by OTOA variations]

Objective: To analyze the phenotypic-genotypic characteristics of hereditary deafness caused by OTOA gene variations. Methods: Family histories, clinical phenotypes and gene variations of six pedigrees were analyzed, which were diagnosed with hearing loss caused by OTOA gene variations at the PLA General Hospital from September 2015 to January 2022. The sequence variations were verified by Sanger sequencing and the copy number variations were validated by multiplex ligation-dependent probe amplification (MLPA) in the family members. Results: The hearing loss phenotype caused by OTOA variations ranged from mild to moderate in the low frequencies, and from moderate to severe in the high frequencies in the probands, which came from six sporadic pedigrees, among which a proband was diagnosed as congenital deafness and five were diagnosed as postlingual deafness. One proband carried homozygous variations and five probands carried compound heterozygous variations in OTOA gene. Nine pathogenic variations (six copy number variations, two deletion variations and one missense variation) and two variations with uncertain significance in OTOA were identified in total, including six copy number variations and five single nucleotide variants, and three of the five single nucleotide variants were firstly reported [c.1265G>T(p.Gly422Val),c.1534delG(p.Ala513Leufs*11) and c.3292C>T(p.Gln1098fs*)]. Conclusions: OTOA gene variations can lead to autosomal recessive nonsyndromic hearing loss. In this study, the hearing loss caused by OTOA defects mostly presents as bilateral, symmetrical, and postlingual, and that of a few presents as congenital. The pathogenic variations of OTOA gene are mainly copy number variations followed by deletion variations and missense variations.

Temperature-dependent UV-Vis dielectric functions of BaTiO3 across ferroelectric-paraelectric phase transition

Ferroelectric BaTiO₃ with an electric-field-switchable spontaneous polarization has attracted wide attention in photovoltaic applications due to its efficient charge separation for photoexcitation. The evolution of its optical properties with rising temperature especially across the ferroelectric-paraelectric phase transition is critical to peer into the fundamental photoexcitation process. Herein, by combining spectroscopic ellipsometry measurements with first-principles calculations, we obtain the UV-Vis dielectric functions of perovskite BaTiO₃ at temperatures varying from 300 to 873 K and provide the atomistic insights into the temperature-driven ferroelectric-paraelectric (tetragonal-cubic) structural evolution. The main adsorption peak in dielectric function of BaTiO₃ is reduced by 20.6% in magnitude and redshifted as temperature increases. The Urbach tail shows an unconventional temperature-dependent behavior due to the microcrystalline disorder across the ferroelectric-paraelectric phase transition and the decreased surface roughness at around 405 K. From ab initio molecular dynamics simulations, the redshifted dielectric function of ferroelectric BaTiO₃ coincidences with the reduction of the spontaneous polarization at elevated temperature. Moreover, a positive (negative) external electric field is applied which can modulate the dielectric function of ferroelectric BaTiO₃ blueshift (redshift) with a larger (smaller) spontaneous polarization since it drives the ferroelectric further away from (closer to) the paraelectric structure. This work sheds light on the temperature-dependent optical properties of BaTiO₃ and provides data support for advancing its ferroelectric photovoltaic applications.

[Phenotypic and genotypic characteristics of Escherichia coli causing bloodstream and abdominal co-infection]

Objective: To analyze the phenotypic and genotypic characteristics of Escherichia coli causing bloodstream and abdominal co-infection (CoECO), and provide clues for empirical antibiotics treatment. Methods: The strains of Escherichia coli isolated from blood and abdominal samples in the Department of Laboratory Medicine of the First Medical Center of the PLA General Hospital from 2010 to 2020 were retrospectively analyzed. Mass spectrometer was used to identify all of the strains and the minimum inhibitory concentration (MIC) were detected by VITEK 2 Compact. All isolates were sequenced by 2×150 bp double terminal sequencing strategy on the HiSeq X Ten sequencer (Illumina). After the genome sequence was spliced, the single nucleotide polymorphism (SNP) analysis of the strain sequence was performed using kSNP3 software to clarify the homologous relationship between strains. If the strains isolated from two different parts had high homology, they were regarded as the same strain and the case was with CoECO infection. Meanwhile, the multilocus sequence type (MLST) was determined using PubMLST website and resistant genes were screened by CARD website. Results: A total of 70 cases of CoECO infection were screened, including 45 males and 25 females, and aged (59.2±16.3) years old. The 70 CoECO isolates belonged to 35 sequence types (STs). The most prevalent STs included ST38 (n=6), ST 405 (n=6), ST 1193 (n=6) and ST131 (n=5), and other ST types contained less than 5 strains. The homologous relationship among strains was relatively scattered, presenting a sporadic trend as a whole, and only a few strains had a small-scale outbreak. The CoECO isolates showed significantly resistance to ampicillin (91.4%, 64/70), ampicillin/sulbactam (74.3%, 5 2/70), ceftriaxone (72.9%, 51/70), ciprofloxacin (71.4%, 50/70) and levofloxacin (71.4%, 50/70), and high-sensitivity to piperacillin/tazobactam, carbapenems and amikacin. The most prevalent resistant gene was tet (A/B) (70%, 49/70), followed by bla_TEM (58.6%, 41/70), sul1 (55.7%, 40/70), sul2 (54.3%, 38/70), bla_CTX-M-14(25.7%, 18/70), bla_CTX-M-15(17.1%, 13/70), bla_CTX-M-55(15.7%, 11/70), bla_CTX-M-64/65(5.7%, 4/70), bla_CTX-M-27(4.3%, 3/70), mcr-1 (4.3%, 3/70), bla_NDM-5(2.9%, 2/70). Conclusions: CoECO is distributed dispersedly and has no obvious advantage clone. No genotype with obvious advantages was found. Although the strain has a high resistance rate to some antibacterial drugs, the proportion of carrying resistant genes is low, and it has a high sensitivity to some first-line antibacterial drugs.

[Attention should be paid to the lifelong monitoring of diabetic retinopathy in people with diabetes]

Diabetic retinopathy (DR) is one of the severe complications of diabetes, and also the most common reason of vision loss in Chinese adults over 30 years old. Regular fundus examination and continuous glucose monitoring can prevent 98% of blindness caused by DR. However, due to the irrational allocation of medical resources and the weak awareness of DR patients, only about 50% to 60% of diabetes patients have an annual DR screening. Therefore, it is necessary to build a follow-up system for early screening, prevention, treatment and lifelong monitoring of DR patients. In this review, we discuss the importance of lifelong monitoring, the hierarchical medical system and the follow-up of pediatric DR patients. Novel and multi-level screening methods are cost-saving to patients and cost-effective to healthcare systems, and also can help improve the detection and early treatment of DR.

Thermal transport across copper-water interfaces according to deep potential molecular dynamics

Nanoscale thermal transport at solid-liquid interfaces plays an essential role in many engineering fields. This work performs deep potential molecular dynamics (DPMD) simulations to investigate thermal transport across copper-water interfaces. Unlike traditional classical molecular dynamics (CMD) simulations, we independently train a deep learning potential (DLP) based on density functional theory (DFT) calculations and demonstrated its high computational efficiency and accuracy. The trained DLP predicts radial distribution functions (RDFs), vibrational densities of states (VDOS), density curves, and thermal conductivity of water confined in the nanochannel at a DFT accuracy. The thermal conductivity decreases slightly with an increase in the channel height, while the influence of the cross-sectional area is negligible. Moreover, the predicted interfacial thermal conductance (ITC) across the copper-water interface by DPMD is 2.505 × 10⁸ W m^-2 K^-1, the same order of magnitude as the CMD and experimental results but with a high computational accuracy. This work seeks to simulate the thermal transport properties of solid-liquid interfaces with DFT accuracy at large-system and long-time scales.

Reactive oxygen species-mediated phosphorylation of JNK is involved in the regulation of BmFerHCH on Bombyx mori nucleopolyhedrovirus proliferation

c-Jun N-terminal kinase (JNK) phosphorylation is widely observed during virus infection, modulating various aspects of the virus-host interaction. In our previous research, we have proved that B. mori ferritin heavy-chain homolog (BmFerHCH), an inhibitor of reactive oxygen species (ROS), facilitates B. mori nucleopolyhedrovirus (BmNPV) proliferation. However, one question remains: Which downstream signaling pathways does BmFerHCH regulate by inhibiting ROS? Here, we first determined that silencing BmFerHCH inhibits BmNPV proliferation, and this inhibition depends on ROS. Then, we substantiated that BmNPV infection activates the JNK signaling pathway. Interestingly, the JNK phosphorylation during BmNPV infection is activated by ROS. Further, we found that the enhanced nuclear translocation of phospho-JNK induced by BmNPV infection was dramatically reduced by pretreatment with the antioxidant N-acetylcysteine (NAC), whereas there was more detectable phospho-JNK in the cytoplasm. Next, we investigated how changes in BmFerHCH expression affect JNK phosphorylation. BmFerHCH overexpression suppressed the phosphorylation of JNK and nuclear translocation of phospho-JNK during BmNPV infection, whereas BmFerHCH knockdown facilitated phosphorylation of JNK and nuclear translocation of phospho-JNK. By measuring the viral load, we found the inhibitory effect of BmFerHCH knockdown on BmNPV infection depends on phosphorylated JNK. In addition, the JNK signaling pathway was involved in BmNPV-triggered apoptosis. Hence, we hypothesize that ROS-mediated JNK phosphorylation is involved in the regulation of BmFerHCH on BmNPV proliferation. These results elucidate the molecular mechanisms and signaling pathways of BmFerHCH-mediated response to BmNPV infection.

Interfacial Reaction and Electromigration Failure of Cu Pillar/Ni/Sn-Ag/Cu Microbumps under Bidirectional Current Stressing

The electromigration behavior of microbumps is inevitably altered under bidirectional currents. Herein, based on a designed test system, the effect of current direction and time proportion of forward current is investigated on Cu Pillar/Ni/Sn-1.8 Ag/Cu microbumps. Under thermo-electric stressing, microbumps are found to be susceptible to complete alloying to Cu6Sn5 and Cu3Sn. As a Ni layer prevents the contact of the Cu pillar with the solder, Sn atoms mainly react with the Cu pad, and the growth of Cu₃Sn is concentrated on the Cu pad sides. With direct current densities of 3.5 × 10⁴ A/cm² at 125 °C, the dissolution of a Ni layer on the cathode leads to a direct contact reaction between the Cu pillar and the solder, and the consumption of the Cu pillar and the Cu pad shows an obvious polarity difference. However, with a bidirectional current, there is a canceling effect of an atomic electromigration flux. With current densities of 2.5 × 10⁴ A/cm² at 125 °C, as the time proportion of the forward current approaches 50%, a polarity structural evolution will be hard to detect, and the influence of the chemical flux on Cu-Sn compounds will be more obvious. The mechanical properties of Cu/Sn3.0Ag0.5Cu/Cu are analyzed at 125 °C with direct and bidirectional currents of 1.0 × 10⁴ A/cm². Compared with high-temperature stressing, the coupled direct currents significantly reduced the mechanical strength of the interconnects, and the Cu-Sn compound layers on the cathode became the vulnerable spot. While under bidirectional currents, as the canceling effect of the electromigration flux intensifies, the interconnect shear strength gradually increases, and the fracture location is no longer concentrated on the cathode sides.

Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande

We report a search for cosmic-ray boosted dark matter with protons using the 0.37  megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1  MeV/c^{2} to 300  MeV/c^{2}.

Nontrivial role of polar optical phonons in limiting electron mobility of two-dimensional Ga2O3 from first-principles

The exfoliated two-dimensional (2D) Ga2O3 opens new avenues to fine-tune the carrier and thermal transport properties for improving the electro-thermal performance of gallium oxide-based power electronics with their enhanced surface-to-volume...

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

[Analysis of clinical prognosis of endoscopic salvage surgery in patients with rT2 recurrent nasopharyngeal carcinoma]

Objective: To investigate the feasibility of endoscopic salvage surgery for patients with rT2 recurrent nasopharyngeal carcinoma (rNPC) and to analyze their prognostic factors. Methods: The clinical data of 33 patients with rT2 rNPC who underwent endoscopic extended nasopharyngectomy in Eye & ENT Hospital Affiliated to Fudan University from January 2015 to July 2020 were analyzed, including 29 males (87.9%) and 4 females (12.1%), aging (51.7±10.6) years. The clinicopathological characteristics of these patients were recorded and analyzed, in terms of gender, sex, alcohol and cigarette use, interval between primary treatment to recurrence, adjuvant therapy, lymph node metastasis, internal carotid artery (ICA) invasion, necrosis, margin and reconstruction materials. Kaplan Meier analysis was used to plot the overall survival rate and progression free survival rate curve, Log-rank test was used to analyze the prognostic factors among patients, and multivariate Cox proportional hazards regression was used to determine the independent risk factors of tumor progression free survival. Results: Among 33 patients with rT2 rNPC, the recurrence interval of 24 patients with rNPC after primary radiotherapy was more than 2 years. A total of 25 patients received primary radiotherapy and adjuvant chemotherapy at the same time. There were 6 cases with cervical lymph node metastasis, 12 cases with ICA invasion, 8 cases with positive surgical margin, 7 cases underwent ICA embolization before operation. A total of 18 cases underwent pedicled tissue flap repairment after operation, including 12 pedicled nasal septal mucosa flaps and 6 temporalis muscle flaps. The median follow-up time was 15 months. Five patients died because of disease progression (in 2 cases), post surgical ICA hemorrhage (in 1 case), liver metastasis (in 1 case) and dysphagia (in 1 case). The 1-year, 2-year and 3-year overall survival rates of all patients were 93.9%, 81.8% and 81.8%, respectively. The 1-year, 2-year and 3-year progression free survival rates were 74.7%, 59.7% and 40.9%, respectively. Log-rank statistical analysis showed that the positive surgical margin (P=0.060) and recurrence interval (P=0.151) were possibly related to the prognosis of rT2 rNPC. Multivariate Cox regression analysis showed that the positive surgical margin was an independent risk factor for patients with rT2 rNPC (P=0.034). Nasopharynx hemorrhage occurred in 4 patients, skull base bone necrosis occurred in 2 patients, trismus occurred in 3 patients, and no obvious brain complications occurred in 7 patients with ICA embolization. Conclusion: Endoscopic salvage surgery for rT2 rNPC is a safe and effective surgical option, but the long-term effect still needs long-term follow-up in bulk cases.

Short and long-term inequity in outpatient medical use by the type of medical institutions in Korea

Background

Many countries agree with the horizontal equity that medical resources should be allocated according to medical needs, regardless of income. Although the short-term equity index calculated through cross-sectional data doesn't reflect the dynamics of individual income and medical use, it can be supplemented by the long-term equity index using panel data. Koreans tend to choose expensive but highly specialized services without considering their medical needs because they are free to choose service providers. This study aims to empirically examine how the patterns of outpatient medical use that are not based on medical needs differ in terms of short- and long-term equity for each type of medical institution.

Methods

Using Korea Health Panel Survey(2014-2018), the equity of outpatient medical use(number of visits, medical expenses) of 10,244 people was measured by type of medical institution (tertiary general hospital, general hospital, hospital, clinic, and dentist). Wagstaff&van Doorslaer(2000)’s tool and Jones & Lopez-Nicolas(2004)’s tool were used to calculate the short and long-term horizontal equity index(HI), and mobility index(MI) to compare short and long-term inequity.

Results

In tertiary general hospitals and dentists, there were short and long-term pro-rich inequalities(HI &gt; 0, p &lt; 0.05). As a result of comparison, long-term inequality was greater in the number of visits (MI &lt; 0), while inequality was easing in the long-term in medical expenses(MI &gt; 0) in tertiary general hospitals. In dentists, long-term inequality was less than short-term inequality in both the number of visits and medical expenses (MI &gt; 0).

Conclusions

The short-term equity index is likely to underestimate or overestimate inequity in our society, so a long-term perspective is needed. Inequality patterns for each type of medical institution should be considered in healthcare reforms for fair distribution of medical resources.

Key messages

• Short-term equity index differs from the long-term equity index in outpatient medical use.

• The pattern of short and long-term equity indices may differ by type of medical institutions.

[Research progress on infiltrating zone and microvascular invasion of hepatic alveolar echinococcosis]

Hepatic alveolar echinococcosis (AE) is a parasitic disease with biological characteristics similar to malignant tumor. It has no obvious clinical symptoms in the early stage. Most patients have complications such as jaundice, ascites and gastrointestinal bleeding when they see a doctor. At this time, the course of disease is at an advanced stage. In addition, the incomplete resection of the AE lesion(s) leads to a high postoperative recurrence rate, which has a serious impact on the physical and mental health of patients. Based on the summary of the latest research at home and abroad and the analysis of blood supply, microvascular invasion and vascular growth factor expression in the "infiltrating zone" adjacent to the lesions of hepatic AE, this article has a deep understanding of the occurrence and development process of hepatic AE, aiming to better guide clinical practice and improve the quality of life of patients.

[Design of non-metallic crown for primary molars and analyzation of stress distribution: a finite element study]

Objectives: To study the design of nonmetallic crowns for deciduous molars by means of computer aided design and to analyze the key parameters of the nonmetallic crowns of deciduous molars using finite element method. Methods: The three-dimensional model of a mandibular second primary molar was constructed by using a micro-CT system. The thickness of the crown was limited to 0.5 mm and four different crown shapes (chamfer+anatomic, chamfer+non-anatomic, knife edge+anatomic and knife edge+non-anatomic) were designed. Then, the crown shape was limited as chamfer+non-anatomic and five different thicknesses of the crown (0.50, 0.75, 1.00, 1.25, 1.50 mm) were designed, and three different materials, including polyetherketoneketone (PEKK), polymethylmethacrylate (PMMA) resin and resin-infiltrated ceramic, were applied to make the crown. Stress distribution and fatigue of each component of the model under vertical and oblique loadings were analyzed by using finite element method. Non-axial retention analysis was performed on chamfer+non-anatomic crowns, made of PMMA resin, with thicknesses of 0.50, 0.75, 1.00, 1.25 and 1.50 mm. Results: Among the four crown shape designs, the chamfer+non-anatomic type crown showed the lowest von Mises stress and the highest safety factor. By comparing three different materials, the resin-infiltrated ceramic group showed obvious stress concentration on the buccal edge of the crown and the PEKK group showed stress concentration in the adhesive layer. Results of non-axial retention analysis showed that the torques required by the crowns with five thicknesses at the same rotation angle were as follows: 4 856.1, 4 038.1, 3 497.3, 3 256.3 and 3 074.3 N⋅m, respectively. The comparison of areas of the adhesives fracture among groups were as follows: 0.5 mm group < 0.75 mm group < 1.00 mm group < 1.25 mm group < 1.50 mm group. Conclusions: In the design of nonmetallic crowns for primary molars, the edge of the crown should be designed as chamfer, the shape of the inner crown should be non-anatomical and the minimum preparation amount of the occlusal surface should be 1.00 mm. Among the three materials, PMMA resin, of which elastic modulus is similar to the dentin and the dental adhesive, might be the most suitable material for the crowns of primary molars.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

Manipulation of Rashba splitting and thermoelectric performance of MTe (M = Ge, Sn, Pb) via Te off-centering distortion

The Rashba effect is an essential phenomenon in asymmetrical ferroelectric materials with local dipole fields. Rashba spin splitting due to spin–orbit coupling in the asymmetrical 2D ferroelectricity MTe (M = Ge, Sn, Pb) has provided a promising arena for achieving an ultra-high power factor to improve their thermoelectric performance. Herein, we show that the hidden Rashba effect may exist in centrosymmetric rock-salt MTe because of the emerging macroscopic electric dipoles caused by the local Te off-centering distortion. Using first-principles calculations, we prove that Te off-centering causes a change in the atomic reciprocal displacement and induces a ferroelectric Rashba effect in rock-salt MTe. Further analyses of the energy evaluation, lattice vibration and chemical orbital confirm that the atomic off-centering behavior manipulates Rashba spin splitting and stereochemical irregularities of the s² lone electron pair of the cation, leading to the formation of strong anharmonic bonds in the original high-symmetry crystalline solids. The changes of the phonon dispersion and electronic structure also affect the electron–phonon scattering and scattering mechanism of MTe, which then manipulates the electrical transport properties. This work unravels the underlying physics on how the local Te off-centering distortion manipulates Rashba spin splitting and improves the thermoelectric performance of MTe.

The hidden Rashba effect emerges in centrosymmetric rock-salt MTe and improves thermoelectric performance due to the local Te off-centering distortion.

Optical properties of biochemical compositions of microalgae within the spectral range from 300 to 1700 nm

The optical properties of biochemical compositions of microalgae are vital for the improvement of biosensor design, photobioreactor design, biofuel, and biophotonics techniques. A combination method using both the double optical pathlength transmission method (DOPTM) and the ellipsometry method (EM) is called DOPTM-EM, and it is used to acquire the optical constants of protein, lipid, and carbohydrate of Haematococcus pluvialis, Nannochloropsis sp., and Spirulina in both a solid state and a solution state within the visible and near-infrared spectral range. For different types of microalgae, the refractive indices of protein and carbohydrate in the solid state are similar to each other, but show an observed difference from lipid in the solid state. The refractive indices of protein and carbohydrate in the solution state presents a visible distinction in the researched spectral range. The absorption indices of protein, lipid, and carbohydrate in the solid state for these three types of microalgae are close to each other in the spectral range of 300-500 nm. However, an observed difference is shown in the spectral range of 500-1700 nm. For ease of application, the refractive index of biochemical composition of microalgae was fitted based on the Sellmeier equation. We believe this work can provide a reference to obtain the optical properties of biomaterial with high accuracy.

Engineering the electronic band structure and thermoelectric performance of GeTe via lattice structure manipulation from first-principles

GeTe has become a high-performance thermoelectric material with a figure of merit (ZT) over two through alloying and band engineering strategies. Yet, the question on how to effectively engineer the electronic band structure of GeTe toward achieving a better thermoelectric performance still cannot be clearly answered, and its underlying physics has not been well understood. Here, we manipulate the lattice structure of GeTe via modifying the lattice parameters, interaxial angles and reciprocal displacements, and investigate their influence on the electronic band structure and thermoelectric properties using first-principles calculations. The calculation results show that the reciprocal displacement directly manipulates the energy level of the L-band and the Z-band, resulting in an indirect-direct transition of the band gap and a strong Rashba effect. Modifications of lattice parameters and interaxial angles can affect band gaps, band convergence and density of states, which are crucial to determining thermoelectric performance. This work performs a systematic study on how the lattice structure manipulation influences the electronic band structure and thermoelectric properties of GeTe, and can provide a clear route to further enhance its ZT.

Temperature-induced surface phonon polaritons dissipation in perovskite SrTiO3

Perovskite SrTiO₃ has emerged as a relevant technological material for nano-photonics that confines light to subdiffraction geometry with remarkably wide spectral tunability. Yet, the influence of lattice vibrations on its surface phonon polaritons (SPhPs) and localized surface phonon resonances (LSPhRs) receives little attention, and the underlying physics still remains elusive. Here, we apply spectroscopic ellipsometry (SE) experiments and multiscale simulations spanning from first-principles to finite-difference time-domain (FDTD), and investigate the temperature influence on infrared dielectric functions, SPhPs and LSPhRs of SrTiO₃. SE measurements find that the width of the Reststrahlen band lying between transverse and longitudinal oxygen-related optical phonons changes slightly, but infrared dielectric functions vary significantly as temperature increases. First-principles calculations confirm the coupling of the motion of oxygen atoms to incident photons, forming quasiparticles of SPhPs. FDTD simulations show that strong LSPhRs exist at 250 K in the SrTiO₃ nanodisks but dissipate as lattice vibration strengthens, mainly due to the reduced phonon relaxation lifetime. This work reveals the underlying physics of temperature influence on SPhPs and LSPhRs of SrTiO₃ and helps explore its potential applications as photonic resonators at high temperatures.

Ellipsometric and first-principles study on temperature-dependent UV-Vis dielectric functions of GaN

The third-generation wide bandgap semiconductor GaN currently occupies a hot spot in the fields of high-power electronics and optoelectronics. Fully exploring its optical and optoelectronic characteristics is of great significance. Here, we provide a systematic study on the temperature-dependent dielectric functions of GaN grown by metal-organic chemical vapor deposition in the spectral range of 0.73-5.90 eV via spectroscopic ellipsometry experiments and first-principles calculations. Ellipsometric measurements identify two typical absorption peaks that originate from the excitonic and phonon-assisted indirect absorption process, respectively. To explore the underlying physics, we perform first-principles calculations using the independent-particle approximation, model Bethe-Salpeter equation (mBSE), and phonon-assisted indirect absorption process (Inabs). In comparison with ellipsometric measurements, the mBSE calculation determines the absorption peak contributed by the many-body excitonic effect, while the Inabs calculation successfully predicts the second absorption peak. When heating the crystal, it observes the redshift and weakening of absorption peaks, intrinsically due to the nontrivial electron-phonon interaction as lattice vibration strengthens. While doping GaN with Fe or Si elements, the introduced free carriers modify the electronic interband transition. As the temperature increases, more free carriers are excited, and the temperature influence on the absorption peak is more significant than that of the undoped one. This work fully explores the physical origins of the temperature and doping effect on UV-Vis dielectric functions of GaN, aiming to promote its application in the fields of high-power electronic devices.

Peta-electron volt gamma-ray emission from the Crab Nebula

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10^-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 10³⁶ ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25  TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160  TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 10¹⁵ electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays¹. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. ²). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane^3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

Assessing the impacts of diversified crop rotation systems on yields and nitrous oxide emissions in Canada using the DNDC model

Process-based models are effective tools for assessing the sustainability of agricultural productivity and environmental health under various management practices and rotation systems. The objectives of this study were to (1) calibrate and evaluate the DeNitrification-DeComposition (DNDC) model using measurements of yields, nitrogen (N) uptake, soil inorganic N, soil temperature, soil moisture and nitrous oxide (N₂O) emissions under long-term fertilized continuous corn (CC) and corn-oats-alfalfa-alfalfa (COAA) rotation systems in southwest Ontario from 1959 to 2015, Canada, and (2) explore the impacts of four diverse rotation systems (CC, COAA, corn-soybean-corn-soybean (CSCS) and corn-soybean-winter wheat (CSW)) on corn yields and annual N₂O emissions under long-term climate variability. DNDC demonstrated "good" performance in simulating corn, oats and alfalfa yield (normalized root mean square error (nRMSE) < 20%, Nash-Sutcliffe efficiency (NSE) > 0.5 and index of agreement (d) > 0.8). The model provided "fair" to "good" simulations for corn N uptake and soil inorganic N (NSE > 0.2 and d > 0.8), and also daily soil temperature and soil moisture (nRMSE <30% and d > 0.7) for both calibration and validation periods. The model demonstrated "good" performance in estimating daily and cumulative N₂O emissions from both the continuous and rotational corn, whereas it produced "poor" to "good" predictions for N₂O emissions from the rotational oats and alfalfa crops, however, the emissions from these crops were very low and the relative magnitude of these emissions between all crops investigated were well predicted. The lowest N₂O emissions were from COAA followed by CSCS, CSW then CC. The highest corn yields were from COAA, followed by CSW, CSCS, then CC. This study highlights how modelling approaches can help improve the understanding of the impacts of diversified rotations on crop production and greenhouse gas emissions and contribute towards developing policies aimed at improving the sustainability and resiliency of cropping systems.

[The involvement of neuropilin-1 in primary immune thrombocytopenia]

Objective: To explore the relationship between the expression of neuropilin-1 (NRP-1) on Treg cells and its ligands semaphorins-3A (Sema3A) , transforming growth factor-β(1) (TGF-β(1)) as well as the balance of type 1 helper T cells (Th(1)) and type 2 helper T cells (Th(2)) cells. Methods: This study enrolled 62 patients with immune thrombocytopenia (ITP; 33 and 29 newly diagnosed and chronic ITP, respectively) from March 2014 to May 2015. Consequently, 30 healthy people in the same period were selected as the normal control group. The expression of NRP-1 in Treg cells was detected via flow cytometry. The Sema3A, TGF-β(1), IFN-γ, and IL-4 levels in plasma were detected by enzyme-linked immunosorbent assay. The real-time polymerase chain reaction technique was used to detect the mRNA expression levels of NRP-1, Sema3A, and TGF-β(1). The one-way analysis of variance and independent sample t-test was used for comparison between three and two groups, respectively. Correlations among the mRNA expression levels of NRP-1, Sema3A, and TGF-β(1) were assessed via Spearman correlation coefficients. Results: Treg cells in the newly diagnosed ITP group significantly increased compared with those in the chronic ITP and normal control groups. The expression of NRP-1 decreased[ (0.15 ± 0.03) %, (0.33 ± 0.15) %, and (0.46 ± 0.06) %; P<0.01], the plasma Sema3A level increased[ (8.10 ± 1.32) μg/L, (7.41±1.30) μg/L, and (2.88±0.82) μg/L; P<0.01], and the plasma TGF-β(1) level decreased[ (16.50±3.36) μg/L, (35.17±10.26) μg/L, and (41.00±10.02) μg/L; P<0.01]. Moreover, the level of plasma IFN-γ increased[ (17.21+2.80) ng/L, (10.23+1.59) ng/L, and (8.18+3.27) ng/L; P<0.01], and the ratios of Th(1)/Th(2) (IFN-γ/IL-4) increased (1.29±0.30, 0.72±0.16, and 0.61±0.27; P<0.01) . The mRNA expressions of NRP-1 and Sema3A in the newly diagnosed ITP and chronic ITP groups were lower than that in the normal control group (P<0.01) . Consequently, the NRP-1 mRNA expression was positively correlated with Sema3A and TGF-β(1) mRNA expression in the newly diagnosed ITP group. Conclusion: NRP-1 played an essential role in the pathogenesis of ITP.

[Veracity of using a visual chart with a testing distance of 2.5 meters for measurement of distance visual acuity in teenagers]

Objective: To compare the results of visual acuity testing for teenagers with visual acuity charts designed at 2.5-meter and 5-meter distances, and to investigate the accuracy of the 2.5-meter visual acuity chart. Methods: It was a self-control study. A total of 227 teenagers (454 eyes) with ametropia who came to the ophthalmic clinic of Peking Union Medical College Hospital from March 2019 to September 2019 were included. There were 123 males and 104 females aged (11.74±3.26) years. The vision examiners were trained in the same testing environment and passed the consistency test. Distance visual acuity of all participants was tested with charts designed at 2.5 meters and 5 meters in a 10-minute interval. According to the age (7-9, 10-12, 13-15 and 16-18 years old) and visual acuity (1.00-0.52, 0.40-0.30 and 0.22-0.10), the results of two kinds of visual acuity charts were compared. The testing order of the two visual charts was randomly determined. The visual acuity results were converted into logMAR values and compared. Paried t-student test was used to compare the difference between two charts, and Pearson correlation test was used to explore the correlation between the results of two charts. Results: The visual acuity of the right eye was 0.37±0.24 (logMAR) at 2.5 meters and 0.50±0.26 (logMAR) at 5 meters. The distance visual acuity measured with the 2.5-meter visual acuity chart was better (t=16.19, P<0.01). The visual acuity of the left eye was 0.36±0.23 (logMAR) at 2.5 meters and 0.45±0.23 (logMAR) at 5 meters (t=11.71, P<0.01). The differences between two charts were larger among teenagers with lower visual acuity (r=0.387,P<0.01). Conclusion: Under the same test conditions, the distance visual acuity measured with a 2.5-meter chart was significantly better than a 5-meter chart. The visual acuity chart designed at 2.5 meters was not an appropriate tool to measure distance vision in adolescents. (Chin J Ophthalmol, 2021, 57: 122-125).

[Research of artificial intelligence-based clinical decision support system for primary hepatocellular carcinoma]

Objective: To apply artificial intelligence technology in clinical real-world data of patients with primary hepatocellular carcinoma, explore the precise treatment of disease and build up artificial intelligence-based clinical decision support system. Methods: A total of 5 642 patients with primary hepatocellular carcinoma admitted to West China Hospital from July 2004 to June 2016 with complete follow-up records were included in the study. A merged model composed of multiple sub-classifiers was adopted to calculate therapy recommendation coefficient, and receiver operator characteristic curve was analyzed. Survival risk and recurrence risk were predicted by DeepSurv algorithm, and Kaplan-Meier survival curves were further compared among low, middle and high risk groups. Siamese-Net was applied to find similar patients. Results: The Top-1 and Top-2 accuracy of therapy recommendation coefficient reached 82.36% and 94.13% respectively. In internal verification of West China Hospital, the above-mentioned value reached 95.10% in accordance with multi-disciplinary team results. The C-index derived from survival risk model was 0.735 (95%CI:0.70-0.77), and the difference of Kaplan-Meier in pairwise comparison was of statistical significance under log-rank test (P<0.001). Meanwhile, the C-index derived from recurrence risk model was 0.705 (95%CI:0.68-0.73), and the difference of Kaplan-Meier in pairwise comparison was of statistical significance under log-rank test (P<0.001). Conclusions: The artificial intelligence-based clinical decision support system for primary hepatocellular carcinoma has can accurately make therapy recommendation and prognosis prediction for primary hepatocellular carcinoma.

A retrospective cohort study of early mortality among patients with HIV/TB co-infection in Shanghai municipality

OBJECTIVES

Tuberculosis (TB) is the most common and fatal opportunistic co-infection among HIV-infected individuals. While TB-associated mortality predominantly occurs in the first 90 days after admission, such a correlation remains unclear in HIV/TB co-infected patients. Thus, we aimed to investigate the 90-day mortality and associated risk factors among HIV/TB co-infected patients in China.

METHODS

Adult patients with HIV and a newly confirmed TB diagnosis admitted to the Shanghai Public Health Clinical Center between September 2009 and August 2017 were enrolled. Clinical and laboratory characteristics, key treatments and outcomes were collected retrospectively. The associations between different factors and early mortality were analysed.

RESULTS

Of the 485 laboratory-confirmed HIV/TB patients [median (range) age = 39 (19-79) years], 413 (85.15%) were male. Diagnosis was confirmed by culture, pathology and acid-fast bacilli smear alone in 362 (74.6%), 6 (1.2%) and 117 (24.1%) patients, respectively. Multiple drug-/rifampin-resistant TB was detected in 21 (5.8%) of the 367 patients with a positive culture. Rifampin or rifabutin was administered to 402 (82.9%) patients. Additionally, 66 (13.6%) and 86 (17.7%) died within 90 days and 1 year of admission, respectively. Of the 64 TB-related deaths, 59 (92.2%) occurred within 90 days of admission. In Cox regression, central nervous system (CNS) TB [odds ratio (OR) = 2.49, 95% confidence interval (CI): 1.46-4.23, P < 0.001], no antiretroviral therapy (ART) within 3 months after admission (OR = 11, 95% CI: 6.4-18.9, P < 0.001), and plasma albumin level < 25 g/L (OR = 1.91, 95% CI: 1.07-3.40, P = 0.021) were associated with early death.

CONCLUSIONS

Tuberculosis co-infection was prevalent and fatal in HIV-infected patients, with most deaths occurring within 90 days of admission. Early mortality was associated with CNS-TB, no ART, and serum albumin level < 25 g/L.

Electric Auxetic Effect in Piezoelectrics

Auxetic materials are characterized by a negative Poisson's ratio that they expand laterally in the directions perpendicular to the applied stretching stress and vice versa. Piezoelectrics will change their dimensions when exposed to an external electric field. Here we introduce the concept of the "electric auxetic effect": electric auxetic materials will contract or expand in all dimensions in response to an electric field. Such unusual piezoelectric response driven by an electric field is a close analogy to the auxetic effect driven by a stress field. A key feature of electric auxetic materials is that their longitudinal and transverse piezoelectric coefficients are of the same sign. We demonstrate using first-principles calculations that the Pca2_{1} orthorhombic phase of ferroelectric HfO_{2} exhibits both the negative longitudinal piezoelectric effect and the electric auxetic effect. The unusual negative longitudinal piezoelectric effect arises unexpectedly from the domination of the negative internal-strain contribution over the positive clamped-ion contribution, a character often found in van der Waals solids. We confirm a few more electric auxetic materials with finite electric field calculations by screening through a first-principles-based database of piezoelectrics.

Machine learning interatomic potential developed for molecular simulations on thermal properties of β-Ga2O3

The thermal properties of β-Ga₂O₃ can significantly affect the performance and reliability of high-power electronic devices. To date, due to the absence of a reliable interatomic potential, first-principles calculations based on density functional theory (DFT) have been routinely used to probe the thermal properties of β-Ga₂O₃. DFT calculations can only tackle small-scale systems due to the huge computational cost, while the thermal transport processes are usually associated with large time and length scales. In this work, we develop a machine learning based Gaussian approximation potential (GAP) for accurately describing the lattice dynamics of perfect crystalline β-Ga₂O₃ and accelerating atomic-scale simulations. The GAP model shows excellent convergence, which can faithfully reproduce the DFT potential energy surface at a training data size of 32 000 local atomic environments. The GAP model is then used to predict ground-state lattice parameters, coefficients of thermal expansion, heat capacity, phonon dispersions at 0 K, and anisotropic thermal conductivity of β-Ga₂O₃, which are all in excellent agreement with either the DFT results or experiments. The accurate predictions of phonon dispersions and thermal conductivities demonstrate that the GAP model can well describe the harmonic and anharmonic interactions of phonons. Additionally, the successful application of our GAP model to the phonon density of states of a 2500-atom β-Ga₂O₃ structure at elevated temperature indicates the strength of machine learning potentials to tackle large-scale atomic systems in long molecular simulations, which would be almost impossible to generate with DFT-based molecular simulations at present.

Spectroscopic identification and catalytic relevance of NH4+ intermediates in selective NOx reduction over Cu-SSZ-13 zeolites

Reduction of harmful nitrogen oxides (NO_x) from diesel engine exhausts is one of the key challenges in environmental protection, and can be achieved by NH₃-assisted selective catalytic reduction (NH₃-SCR) using copper-exchanged chabazite zeolites (i.e. Cu-CHA, including Cu-SSZ-13 and Cu-SAPO-34) as catalysts. Understanding the redox chemistry of Cu-CHA in NH₃-SCR catalysis is crucial for further improving the NO_x reduction efficiency. Here, a series of Cu-SSZ-13 catalysts with different Cu ion exchange levels were prepared, thoroughly characterized by different techniques such as X-ray diffraction, diffuse reflectance ultraviolet-visible spectroscopy and temperature-programmed desorption using NH₃ as a probe molecule, etc., and tested in NH₃-SCR reactions under steady-state conditions. In situ studies by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), supplemented with density-functional theory calculations, provided solid evidence for the formation of ammonium ion (NH₄⁺) intermediates resulting from the reduction of Cu²⁺ to Cu⁺ by co-adsorbed NH₃ and NO molecules on Cu-SSZ-13. Catalytic relevance of the NH₄⁺ intermediates, as demonstrated by an increase of NO conversion over Cu-SSZ-13 pre-treated in NH₃/NO atmosphere, can be attributed to the formation of closely coupled Cu⁺/NH₄⁺ pairs promoting the Cu⁺ re-oxidation and, consequently, the overall NH₃-SCR process. This study thus paves a new route for improving the NH₃-SCR efficiency over Cu-CHA zeolite catalyst.

[Preliminary study of the relationship between novel coronavirus pneumonia and liver function damage: a multicenter study]

Objective: To analyze the clinical characteristics of cases of novel coronavirus pneumonia and a preliminary study to explore the relationship between different clinical classification and liver damage. Methods: Consecutively confirmed novel coronavirus infection cases admitted to seven designated hospitals during January 23, 2020 to February 8, 2020 were included. Clinical classification (mild, moderate, severe, and critical) was carried out according to the diagnosis and treatment program of novel coronavirus pneumonia (Trial Fifth Edition) issued by the National Health Commission. The research data were analyzed using SPSS19.0 statistical software. Quantitative data were expressed as median (interquartile range), and qualitative data were expressed as frequency and rate. Results: 32 confirmed cases that met the inclusion criteria were included. 28 cases were of mild or moderate type (87.50%), and four cases (12.50%) of severe or critical type. Four cases (12.5%) were combined with one underlying disease (bronchial asthma, coronary heart disease, malignant tumor, chronic kidney disease), and one case (3.13%) was simultaneously combined with high blood pressure and malignant tumor. The results of laboratory examination showed that the alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin (ALB), and total bilirubin (TBil) for entire cohort were 26.98 (16.88 ~ 46.09) U/L and 24.75 (18.71 ~ 31.79) U/L, 39.00 (36.20 ~ 44.20) g/L and 16.40 (11.34 ~ 21.15) μmol/L, respectively. ALT, AST, ALB and TBil of the mild or moderate subgroups were 22.75 (16.31 ~ 37.25) U/L, 23.63 (18.71 ~ 26.50) U/L, 39.70 (36.50 ~ 46.10) g/L, and 15.95 (11.34 ~ 20.83) μmol/L, respectively. ALT, AST, ALB and TBil of the severe or critical subgroups were 60.25 (40.88 ~ 68.90) U/L, 37.00 (20.88 ~ 64.45) U/L, 35.75 (28.68 ~ 42.00) g/L, and 20.50 (11.28 ~ 25.00) μmol/L, respectively. Conclusion: The results of this multicenter retrospective study suggests that novel coronavirus pneumonia combined with liver damage is more likely to be caused by adverse drug reactions and systemic inflammation in severe patients receiving medical treatment. Therefore, liver function monitoring and evaluation should be strengthened during the treatment of such patients.