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The discovery of covalent H3S and clathrate structure LaH10 with excellent superconducting critical temperatures at high pressures has facilitated a multitude of research on compressed hydrides. However, their superconducting pressures are too high (generally above 150 GPa), thereby hindering their application. In addition, making room-temperature superconductivity close to ambient pressure in hydrogen-based superconductors is challenging. In this work, we calculated the chemically “pre-compressed” Be-H by heavy metals Th and Ce to stabilize the superconducting phase near ambient pressure. An unprecedented ThBeH8 (CeBeH8) with a “fluorite-type” structure was predicted to be thermodynamically stable above 69 GPa (76 GPa), yielding a Tc of 113 K (28 K) decompressed to 7 GPa (13 GPa) by solving the anisotropic Migdal–Eliashberg equations. Be-H vibrations play a vital role in electron–phonon coupling and structural stability of these ternary hydrides. Our results will guide further experiments toward synthesizing ternary hydride superconductors at mild pressures.

Abstract Due to the BCS theory, hydrogen, the lightest element, would be the prospect of room-temperature superconductor after metallization, but because of the difficulty of the hydrogen metallization, the theory about hydrogen pre-compression was proposed that the hydrogen-rich compounds could be a great option for the high T c superconductors. The superior properties of TmH6, YbH6 and LuH6 indicated the magnificent potential of heavy rare earth elements for low-pressure stability. Here, we designed XTmH12 (X = Y, Yb, Lu, and La) to obtain higher T c while maintaining low pressure stability. Most prominently, YbTmH12 can stabilize at a pressure of 60 GPa. Compared with binary TmH6 hydride, its T c was increased to 48 K. The results provide an effective method for the rational design of moderate pressure stabilized hydride superconductors.

Abstract Achieving superconductivity at room temperature (RT) is a holy grail in physics. Recent discoveries on high‐Tc superconductivity in binary hydrides H3S and LaH10 at high pressure have directed the search for RT superconductors to compress hydrides with conventional electron–phonon mechanisms. Here, an exceptional family of superhydrides is predicated under high pressures, MH12 (M = Mg, Sc, Zr, Hf, Lu), all exhibiting RT superconductivity with calculated Tcs ranging from 313 to 398 K. In contrast to H3S and LaH10, the hydrogen sublattice in MH12 is arranged as quasi‐atomic H2 units. This unique configuration is closely associated with high Tc, attributed to the high electronic density of states derived from H2 antibonding states at the Fermi level and the strong electron–phonon coupling related to the bending vibration of H2 and H‐M‐H. Notably, MgH12 and ScH12 remain dynamically stable even at pressure below 100 GPa. The findings offer crucial insights into achieving RT superconductivity and pave the way for innovative directions in experimental research.

Abstract Superconductivity at room temperature and near‐ambient pressures is a highly sought‐after phenomenon in physics and materials science. A recent study reported the presence of this phenomenon in N‐doped lutetium hydride [Nature 615, 244 (2023)], however, subsequent experimental and theoretical investigations have yielded inconsistent results. This study undertakes a systematic examination of synthesis methods involving high temperatures and pressures, leading to insights into the impact of the reaction path on the products and the construction of a phase diagram for lutetium hydrides. Notably, the high‐pressure phase of face‐centered cubic LuH3 (fcc‐LuH3) is maintained to ambient conditions through a high‐temperature and high‐pressure method. Based on temperature and anharmonic effects corrections, the lattice dynamic calculations demonstrate the stability of fcc‐LuH3 at ambient conditions. However, no superconductivity is observed above 2 K in resistance and magnetization measurements in fcc‐LuH3 at ambient pressure. This work establishes a comprehensive synthesis approach for lutetium hydrides, thereby enhancing the understanding of the high‐temperature and high‐pressure method employed in hydrides with superconductivity deeply.

Abstract Analysis of the superconducting properties of transition metal dichalcogenides (TMDs) under high pressures offers valuable insights to guide the design and synthesis of high‐performance superconducting materials. Herein, the effect of pressure is investigated on the superconductivity of a typical van der Waals layered TMDs material, PdSSe, by measuring its transport properties. After initially increased pressure, superconductivity emerges at 10.2 GPa, with a critical superconducting temperature (Tc) of ≈5.1 K, accompanied by the diminishing charge density wave (CDW) that is originally strengthening. Then, the Tc gradually increases with increasing pressure, reaching 12.1 K at the maximum pressure. The study provides experimental evidence for the superconductivity of PdSSe, and to the best of the knowledge, this is the first report on the observation of amplified CDW phenomena under increasing pressure in nonmagnetic TMDs. The abnormal enhancement of CDW transition temperature at low pressure is consistent with the upward trend of resistance, which is related to the electron–electron interaction. Moreover, synchrotron X‐ray diffraction experiments reveal two additional structural phase transitions.

Superconducting electrides are characterized by the emergence of electrons occupying the interstitial region of lattice and exhibit coexistence of distinctive electride state and superconductivity, which have attracted wide attention. However, the underlying crucial factors governing the superconductivity and influencing the structural stability by electride states remain elusive. Here, we performed structure searches in conjunction with first-principles calculations to identify a dynamically stable electride Be6C at 40 GPa, which exhibits p-orbital type electride states and demonstrates superconductivity with a Tc of 22.4 K. Furthermore, it remains dynamically stable even down to ambient conditions while maintaining a Tc of 18.9 K. Further analyses unveiled that the dual p-hybridized electrons within the orbitals of p-orbital electride states and Be-2p mainly composed of a van Hove singularity near the Fermi level and participate in electron–phonon interaction to form Cooper pairs leading to the high-Tc. The preservation of dynamic stability for Be6C at low pressure is primarily attributed to the presence of electride states that effectively form both covalent and ionic bonding properties to bind neighbor Be cations to lower enthalpy of system and subsequently, in turn, lowering the required pressure. Our findings not only explained the underlying factors affecting superconductivity but also revealed the crucial role of electride states in determining the dynamic stability of structure, providing valuable insights for subsequent research on superconducting electrides at low pressures.

Purity metallic materials are increasingly demanded in modern manufacturing industries, but their applications are limited owing to their poor wear resistance and mechanical properties. Therefore, exploring an efficient hardening method to significantly enhance the hardness of pure metals is emergent in materials science. In this work, a series of high pressure and high temperature (HPHT) quenching experiments were carried out on several pure metals, with a maximum hardening factor exceeding 10. The results indicated that pressure has an unusual effect on refining grains and increasing the Hall–Petch coefficient ky. The ky value of pure Fe is 49.5 GPa*μm1/2 with a quenching pressure of 5 GPa, which is two orders higher than that of the untreated polycrystalline sample (0.2 GPa*μm1/2). In addition, we report an extreme hardness of 8.34 GPa in pure Ti induced by HPHT quenching, and the unprecedented hardening comes from the formation of the twin and lath martensitic substructures. The hardening mechanism of the HPHT quenching method is a combination of Hall–Petch hardening and work-hardening. Our results provide a practical route to achieve attractive mechanical properties in pure metals and shine a light on the hardening mechanism of metallic materials.

Abstract Ternary hydrides are regarded as an important platform for exploring high-temperature superconductivity at relatively low pressures. Here, we successfully synthesized the hcp-(La,Ce)H9-10 at 113 GPa with the initial La/Ce ratio close to 3:1. The high-temperature superconductivity was strikingly observed at 176 K and 100 GPa with the extrapolated upper critical field H c2(0) reaching 235 T. We also studied the binary La-H system for comparison, which exhibited a T c of 103 K at 78 GPa. The T c and H c2(0) of the La-Ce-H are respectively enhanced by over 80 K and 100 T with respect to the binary La-H and Ce-H components. The experimental results and theoretical calculations indicate that the formation of the solid solution contributes not only to enhanced stability but also to superior superconducting properties. These results show how better superconductors can be engineered in the new hydrides by large addition of alloy-forming elements.

One of the most important technologies in modern information and service industry is social influence analysis.More and more researchers in social networks focus on social influence.Real social networks are evolving rather than static.The proposal of evolutionary network also brings new challenges and opportunities.At the same time,the massive social information in the evolutionary network also provides strong support for the rapid development of big data analysis technology.In this paper,evolutionary network and influence maximization are discussed.It also discusses the diffusion model of social influence analysis and the influence analysis method based on social network big data.At the same time,some widely used influence algorithms are further sorted out.In addition,this paper also discusses the relationship between big data,evolutionary networks,and social influence maximization.This paper aims to help other researchers to better understand the existing work and provide new ideas for the influence analysis of social networks through the influence analysis of large-scale social networks.

Recently, room-temperature superconductivity has been reported in a nitrogen-doped lutetium hydride at near-ambient pressure [Dasenbrock-Gammon et al., Nature 615, 244 (2023)]. The superconducting properties might arise from Fm3̄m-LuH3−δNε. Here, we systematically study the phase diagram of Lu–N–H at 1 GPa using first-principles calculations, and we do not find any thermodynamically stable ternary compounds. In addition, we calculate the dynamic stability and superconducting properties of N-doped Fm3̄m-LuH3 using the virtual crystal approximation (VCA) and the supercell method. The R3m-Lu2H5N predicted using the supercell method could be dynamically stable at 50 GPa, with a Tc of 27 K. According to the VCA method, the highest Tc is 22 K, obtained with 1% N-doping at 30 GPa. Moreover, the doping of nitrogen atoms into Fm3̄m-LuH3 slightly enhances Tc, but raises the dynamically stable pressure. Our theoretical results show that the Tc values of N-doped LuH3 estimated using the Allen–Dynes-modified McMillan equation are much lower than room temperature.

Ultra-low lattice thermal conductivity has long been a requirement for the high thermoelectric properties of materials. In this work, the novel 1T-Au6Se2 monolayer was obtained by introducing Au6 clusters into the selenide monolayer, and its electrical and thermal transport characteristics are investigated using first-principles computations supplemented with semi-classical Boltzmann transport theory. The calculation shows that the 1T-Au6Se2 monolayer exhibits ultra-low lattice thermal conductivity and excellent thermoelectric properties owing to its low phonon frequency, group velocity, and extremely strong anharmonicity. Based on strain engineering from 0% to 2%, the lattice thermal conductivity further reduces by restricting the thermal transport on the premise of maintaining outstanding electrical transport properties in the p-type doped system. Thence, the value of ZT for the p-type system increases nearly by 70% compared with the non-stressed state at 700 K. Our investigation indicates the ultra-low thermal conductivity and high ZT of the 1T-Au6Se2 monolayer that might be prepared in the lab, providing new insights into enhancing the thermoelectric performance of the material in the future.

Summary: d−d orbital coupling, which increases anisotropic and directional bonding, commonly occurs between d-block transition metals. Here, we report an unexpected d−d orbital coupling in the non-d-block main-group element compound Mg2I based on first-principles calculations. The unfilled d orbitals of Mg and I atoms under ambient conditions become part of the valence orbitals and couple with each other under high pressures, resulting in the formation of highly symmetric I−Mg−I covalent bonding in Mg2I, which forces the valence electrons of Mg atoms into the lattice voids to form interstitial quasi-atoms (ISQs). In turn, the ISQs highly interact with the crystal lattice, contributing to lattice stability. This study greatly enriches the fundamental understanding of chemical bonding between non-d-block main-group elements at high pressures.

Pressure engineering in two-dimensional semiconductor materials, represented by metal phosphorus trichalcogenides (MPTs), has successfully induced diverse novel physical phenomena such as spin-crossover, volume collapse, piezochromism, metallization, and superconductivity. As a typical member of the MPT family, SnPSe3 exhibits exceptional pressure responses, e.g., structural phase transitions, shrinkage of band gap, metallization and superconductivity. However, there is a lack of study on the optoelectronic performance under pressure, which may promote the exploration of high-performance MPT-based photodetectors. Here, the remarkably improved optoelectronic properties of SnPSe3 with high photocurrent density Jph (8.6 × 104 μA cm-2), responsivity R (4.2 × 105 μA W-1), and external quantum efficiency (EQE) (8.4 × 105) are obtained via introducing pressure, which represent almost three orders of magnitude increment compared to the initial values. Combining high-pressure UV-vis absorption and Raman spectral measurements, as well as theoretical calculations, i.e., electronic band structure, electron localization function and Bader charge, it was found that the pressure-enhanced photoelectric properties are mainly associated with the decrease of interatomic distances and the enhancement of interatomic interactions between P-P atoms as well as P-Se atoms, which promotes charge transfer and eventually leads to photocurrent improvement in compressed SnPSe3. The discovery of pressure-enhanced optoelectronic properties in SnPSe3 offers an effective means of regulating photoelectric properties and stimulates the exploration of the novel properties of two-dimensional semiconductors. [ABSTRACT FROM AUTHOR]

Abstract In desert habitats, sand burial is an important factor affecting germination of plant seeds and seedling growth. Xanthium spinosum has strong adaptability in arid desert areas, and is a common malignant invasive plant in Xinjiang, China. The effects of different sand burial depths on seed germination, seedling emergence, growth and biomass allocation were studied to provide a scientific basis for further control of X. spinosum. Six sand burial depths (1, 2, 3, 5, 7 and 9 cm) were established to explore the response of X. spinosum seed germination and seedling growth to sand burial. The first emergence time, peak emergence time, emergence rate, seedling growth height, biomass and biomass distribution of X. spinosum seeds was significantly different at sand burial depths (P < 0.05). The X. spinosum seeds had the highest emergence rate (71.5%) at 1 cm sand burial and the maximum seedling height (7.1 cm). As sand burial depth increased, the emergence rate and seedling height gradually decreased. Emergence rate (12.25%) and seedling height (2.9 cm) were lowest at 9 cm sand burial. The root length at 9 cm depth (13.6 cm) was significantly higher than that at other sand depths (P < 0.05). The sand burial depth affected the biomass accumulation and distribution of X. spinosum. As sand burial depth increased, the root biomass and rhizome ratio increased, and the most deeply buried seedlings allocated more biomass for root growth. The optimal sand burial depth for seed germination and seedling growth of X. spinosum was 1–3 cm, and high burial depth (5–9 cm) was not conducive to the germination and growth of X. spinosum seedlings. For prevention and control of X. spinosum, we suggest deeply ploughing crops before sowing to ensure X. spinosum seeds are ploughed into a deep soil layer.

High pressure can modify the chemical properties of the elements, giving rise to exotic bonding. Here the authors report the prediction of a nitrogen-rich iodine nitride compound IN6 where the iodine atom has an unusual twelve-fold coordination, stable above 100 GPa.

Finding room-temperature superconductors is one of the most important subjects in scientific search. Due to its hydrogen clathrate structures, LaH10 has become one of the widely known room-temperature superconductors under pressure. So exploring the role of hydrogen content would help understanding the mechanism of superconductivity in the hydrides. Here, we explore the evolution of hydrogen content in lanthanum hydrides based on the first-principles calculations. We found new lanthanum hydrides at pressures, such as Cmcm-LaH. The electronic properties and electron–phonon coupling have been studied and found that Fm3¯m-LaH obtained an unexpected low Tc of ∼ 0.001 K. The superconductive mechanism has been studied in LaHx (x = 0, 1, 2, 3, 8, 10), where LaH0 means elemental lanthanum. We found that low content of hydrogen depresses the electron–phonon interaction in La–H compounds before H–H bonds formed. But with the increases of H content, the strong electron–phonon coupling of H atoms would help the compounds obtain high Tc. This result would explain the lanthanum hydrides with lower H content obtain weaker electron–phonon coupling and could not became potential high-temperature superconductors.

A new dysprosium (III) coordination polymer [Dy(Hm-dobdc) (H2O)2]·H2O (Dy-CP), was hydrothermal synthesized based on 4,6-dioxido-1,3-benzenedicarboxylate (H4m-dobdc) ligand containing carboxyl and phenolic hydroxyl groups. The Dy(III) center adopts an octa-coordinated [DyO8] geometry, which can be described as a twisted square antiprism (D4d symmetry). Neighboring Dy(III) ions are interconnected by deprotonated Hm-dobdc3− ligand to form the two-dimensional infinite layers, which are further linked to generate three-dimensional structure through abundant hydrogen bonds mediated primarily by coordinated and lattice H2O molecules. Magnetic studies demonstrates that Dy-CP shows the field-induced slow relaxation of magnetization and the energy barrier Ueff/kB and relaxation time τ0 are 35.3 K and 1.31 × 10–6 s, respectively. Following the vehicular mechanism, Dy-CP displays proton conductivity with σ equal to 7.77 × 10–8 S cm−1 at 353 K and 30%RH. Moreover, luminescence spectra reveal that H4m-dobdc can sensitize characteristic luminescence of Dy(III) ion. Herein, good magnetism, proton conduction, and luminescence are simultaneously achieved, and thus, Dy-CP is a potential multifunctional coordination polymer material.

The temperature dependence of the Al2O3 solubility in bridgmanite has been determined in the system MgSiO3–Al2O3 at temperatures of 2750–3000 ​K under a constant pressure of 27 ​GPa using a multi-anvil apparatus. Bridgmanite becomes more aluminous with increasing temperatures. A LiNbO3-type phase with a pyrope composition (Mg3Al2Si3O12) forms at 2850 ​K, which is regarded as to be transformed from bridgmanite upon decompression. This phase contains 30 ​mol% Al2O3 at 3000 ​K. The MgSiO3 solubility in corundum also increases with temperatures, reaching 52 ​mol% at 3000 ​K. Molar volumes of the hypothetical Al2O3 bridgmanite and MgSiO3 corundum are constrained to be 25.95 ​± ​0.05 and 26.24 ​± ​0.06 ​cm3/mol, respectively, and interaction parameters of non-ideality for these two phases are 5.6 ​± ​0.5 and 2.2 ​± ​0.5 ​KJ/mol, respectively. The increases in Al2O3 and MgSiO3 contents, respectively, in bridgmanite and corundum are caused by a larger entropy of Al2O3 bridgmanite plus MgSiO3 corundum than that of MgSiO3 bridgmanite plus Al2O3 corundum with temperature, in addition to the configuration entropy. Our study may help explain dynamics of the top lower mantle and constrain pressure and temperature conditions of shocked meteorites.

Background: As the most important modifications on the RNA level, N6‐methyladenosine (m6A‐) and 5‐methylcytosine (m5C‐) modification could have a direct influence on the RNAs. Long non‐coding RNAs (lncRNAs) could also be modified by methylcytosine modification. Compared with mRNAs, the function of lncRNAs could be more potent to some extent in biological processes like tumorigenesis. Until now, rare reports have been done associated with cutaneous melanoma. Herein, we wonder if the m6A‐ and m5C‐ modified lncRNAs could influence the immune landscape and prognosis in melanoma, and we also want to find some lncRNAs which could directly affect the malignant behaviors of melanoma. Methods: Systematically, we explored the expression pattern of m6A‐ and m5C‐ modified lncRNAs in melanoma from datasets including UCSC Xena and NCBI GEO, and the prognostic lncRNAs were selected. Then, according to the expression pattern of lncRNAs, melanoma samples from these datasets were divided into several subtypes. Prognostic model, nomogram survival model, drug sensitivity, GO, and KEGG pathway analysis were performed. Furthermore, among several selected lncRNAs, we identified one lncRNA named LINC00893 and investigated its expression pattern and its biological function in melanoma cell lines. Results: We identified 27 m6A‐ and m5C‐ related lncRNAs which were significantly associated with survival, and we made a subtype analysis of melanoma samples based on these 27 lncRNAs. Among the two subtypes, we found differences of immune cells infiltration between these two subtypes. Then, LASSO algorithm was used to screen the optimized lncRNAs combination including ZNF252P‐AS1, MIAT, FAM13A‐AS1, LINC‐PINT, LINC00893, AGAP2‐AS1, OIP5‐AS1, and SEMA6A‐AS1. We also found that there was a significant correlation between the different risk groups predicted based on RS model and the actual prognosis. The nomogram survival model based on independent survival prognostic factors was also constructed. Besides, sensitivity to chemotherapeutic agents, GO and KEGG analysis were performed. In different risk groups, a total of 14 drug molecules with different distributions were obtained, which included AZD6482, AZD7762, AZD8055, camptothecin, dasatinib, erlotinib, gefitinib, gemcitabine, GSK269962A, nilotinib, rapamycin, and sorafenib. A total of 55 significantly related biological processes and 17 KEGG signaling pathways were screened. At last, we noticed that LINC00893 had a relatively lower expression in melanoma tissue and cell lines compared with adjacent tissues and epidermal melanocyte, and down‐regulation of LINC00893 could promote the malignant behavior of melanoma cells in A875 and MV3. In these two melanoma cell lines, down‐regulation of m6A‐related molecules like YTHDF3 and METTL3 could promote the expression of LINC00893. Conclusion: We made an analysis of m6A‐ and m5C‐ related lncRNAs in melanoma samples and a prediction of these lncRNAs' role in prognosis, tumor microenvironment, immune infiltration, and clinicopathological features. We also found that LINC00893, which is potentially regulated by m6A modification, could serve as a tumor‐suppressor in melanoma and play an inhibitory role in melanoma metastasis. [ABSTRACT FROM AUTHOR]

Abstract Background TCAB1, a.k.a. WRAP53β or WDR79, is an important molecule for the maintenance of Cajal bodies and critically involved in telomere elongation and DNA repair. Upregulation of TCAB1 were discovered in a variety types of cancers. However, the function of TCAB1 in tumor cell senescence remains absent. Methods The TCAB1 knockdown cell lines were constructed. The expression levels of TCAB1, p21, p16 and p53 were detected by qRT-PCR and western blotting. Staining of senescence-associated β-galactosidase was used to detect senescent cells. The ubiquitination of the p21 was analysed by immunoprecipitation and in vivo ubiquitination assay. TCGA databases were employed to perform in silico analyses for the mRNA expression of TCAB1, p21, p16 and p53. Results Here, we discovered that knockdown of TCAB1 induced rapid progression of cellular senescence in A549, H1299 and HeLa cells. In exploiting the mechanism underlining the role of TCAB1 on senescence, we found a significant increase of p21 at the protein levels upon TCAB1 depletion, whereas the p21 mRNA expression was not altered. We verified that TCAB1 knockdown was able to shunt p21 from proteasomal degradation by regulating the ubiquitination of p21. In rescue assays, it was demonstrated that decreasing the expression of p21 or increasing the expression of TCAB1 were able to attenuate the cellular senescence process induced by TCAB1 silencing. Conclusions This study revealed the importance of TCAB1 for its biological functions in the regulation of cell senescence. Our results will be helpful to understand the mechanisms of senescence in cancer cells, which could provide clues for designing novel strategies for developing effective treatment regimens.

Metallization of pure hydrogen via overlapping of electronic bands requires high pressure above 3 Mbar. Here the authors study the Ba-H system and discover a unique superhydride BaH12 that contains molecular hydrogen, which demonstrates metallic properties and superconductivity below 1.5 Mbar.

Abstract Background Analysis of the risk factors associated with functional delayed gastric emptying after distal gastric cancer surgery to provide a basis for further reduction of the incidence of this complication. Methods Total of 1382 patients with distal gastric cancer from January 2016 to October 2018 were enrolled. Correlation analysis was performed in 53 patients with FDGE by logistic regression. Subgroup risk analysis was performed in 114 patients with preoperative pyloric obstruction. A Pearson Chi-square analysis was used to compare categorical variables between normal distribution groups. Meanwhile, a t test was used to compare continuous variables between groups. Odds ratio (OR) was used for comparison of the two groups, and it was summarized with its 95% confidence interval (CI) and p value using logistic regression. Result In multivariable analysis, age (OR 1.081, 95% CI, 1.047–1.117), BMI (OR 1.233, 95% CI, 1.116–1.363), preoperative pyloric obstruction (OR 3.831, 95% CI, 1.829–8.023), smaller volume of residual stomach (OR 1.838, 95% CI, 1.325–6.080), and anastomosis in greater curvature perpendicular (OR 3.385, 95% CI, 1.632–7.019) and in greater curvature parallel (OR 2.375, 95% CI, 0.963–5.861) were independent risk factors of FDGE. In the preoperative pyloric obstruction group, higher BMI (OR 1.309, 95% CI, 1.086–1.579) and preoperative obstruction time (OR 1.054, 95% CI, 1.003–1.108) were independent risk factors of FDGE and preoperative gastrointestinal decompression (OR 0.231, 95% CI, 0.068–0.785) was independent protective factor of FDGE. Conclusion Adequate gastrointestinal decompression should be performed before the operation to reduce the incidence of postoperative gastroparesis in patients with preoperative pyloric obstruction. We also could improve the surgical methods to reduce the occurrence of FDGE, such as controlling the size of the residual stomach, ensuring blood supply. Especially selecting an appropriate stapler and anastomosis during the anastomosis process, the occurrence of FDGE can be reduced.

Botulinum neurotoxins (BoNTs) are among the most toxic proteins. Vaccination is an effective strategy to prevent botulism. To generate a vaccine suitable for human use, a recombinant non-His-tagged isoform of the Hc domain of botulinum neurotoxin serotype E (rEHc) was expressed in Escherichia coli and purified by sequential chromatography. The immunogenicity of rEHc was evaluated in mice and dose- and time-dependent immune responses were observed in both antibody titers and protective potency. Then, the pilot-scale expression and purification of rEHc were performed, and its immunological activity was characterized. Our results showed rEHc has good immunogenicity and can elicit strong protective potency against botulinum neurotoxin serotype E (BoNT/E) in mice, indicating that rEHc is an effective botulism vaccine candidate. Further, we developed a novel antitoxin against BoNT/E by purifying F(abʹ)2 from pepsin-digested serum IgG of rEHc-inoculated horses. The protective effect of the F(abʹ)2 antitoxin was determined in vitro and in vivo. The results showed that our F(abʹ)2 antitoxin can prevent botulism in BoNT/E-challenged mice and effectively alleviate the progression of paralysis caused by BoNT/E to achieve therapeutic effects. Therefore, our results provide valuable experimental data for the production of a novel antitoxin, which is a promising candidate for the treatment of BoNT/E-induced botulism.

Abstract Background The status of lymph nodes in early gastric cancer is critical to make further clinical treatment decision, but the prediction of lymph node metastasis remains difficult before operation. This study aimed to develop a nomogram that contained preoperative factors to predict lymph node metastasis in early gastric cancer patients. Methods This study analyzed the clinicopathologic features of 823 early gastric cancer patients who underwent gastrectomy retrospectively, among which 596 patients were recruited in the training cohort and 227 patients in the independent validation cohort. Significant risk factors in univariate analysis were further identified to be independent variables in multivariable logistic regression analysis, which were then incorporated in and presented with a nomogram. And internal and external validation curves were plotted to evaluate the discrimination of the nomogram. Results Totally, six independent predictors, including the tumor size, macroscopic features, histology differentiation, P53, carbohydrate antigen 19-9, and computed tomography-reported lymph node status, were enrolled in the nomogram. Both the internal validation in the training cohort and the external validation in the validation cohort showed the nomogram had good discriminations, with a C-index of 0.82 (95%CI, 0.78 to 0.86) and 0.77 (95%CI, 0.60 to 0.94) respectively. Conclusions Our study developed a new nomogram which contained the most common and significant preoperative risk factors for lymph node metastasis in patients with early gastric cancer. The nomogram can identify early gastric cancer patients with the high probability of lymph node metastasis and help clinicians make more appropriate decisions in clinical practice.

Room temperature superconductivity is a dream that mankind has been chasing for a century. In recent years, the synthesis of H3S, LaH10, and C-S-H compounds under high pressures has gradually made that dream become a reality. But the extreme high pressure required for stabilization of hydrogen-based superconductors limit their applications. So, the next challenge is to achieve room-temperature superconductivity at significantly low pressures, even ambient pressure. In this work, we design a series of high temperature superconductors that can be stable at moderate pressures by incorporating heavy rare earth elements Yb/Lu into sodalite-like clathrate hexahydrides. In particular, the critical temperatures (Tc) of Y3LuH24, YLuH12, and YLu3H24 can reach 283 K at 120 GPa, 275 K at 140 GPa, and 288 K at 110 GPa, respectively. Their critical temperatures are close to or have reached room temperature, and minimum stable pressures are significantly lower than that of reported room temperature superconductors. Our work provides an effective method for the rational design of low-pressure stabilized hydrogen-based superconductors with room-temperature superconductivity simultaneously and will stimulate further experimental exploration.

The hardness of materials is a complicated physical quantity, and the hardness models that are widely used do not function well for transition metal light element (TMLE) compounds. The overestimation of actual hardness is a common phenomenon in hardness models. In this work, high-quality Mn3N2 bulk samples were synthesized under high temperature and high pressure (HTHP) to investigate this issue. The hardness of Mn3N2 was found to be 9.9 GPa, which was higher than the hardness predicted using Guo’s model of 7.01 GPa. Through the combination of the first-principle simulations and experimental analysis, it was found that the metal bonds, which are generally considered helpless to the hardness of crystals, are of importance when evaluating the hardness of TMLE compounds. Metal bonds were found to improve the hardness in TMLEs without strong covalent bonds. This work provides new considerations for the design and synthesis of high-hardness TMLE materials, which can be used to form wear-resistant coatings over the surfaces of typical alloy materials such as stainless steels. Moreover, our findings provide a basis for establishing a more comprehensive theoretical model of hardness in TMLEs, which will provide further insight to improve the hardness values of various alloys.

High-quality P6322 Mn2N0.86 samples were synthesised using a high-pressure metathesis reaction, and the properties of the material were investigated. The measurements revealed that the Vickers hardness was 7.47 GPa, which is less than that predicted by commonly used theoretical models. At low air pressure, Mn2N0.86 and MnO coexist at 500 to 600 °C, and by excluding air, we succeeded in producing Mn4N by heating Mn2N0.86 in nitrogen atmosphere; we carefully studied this process with thermogravimetry and differential scanning calorimetry (TG-DSC). This gives a hint that to control temperature, air pressure and gas concentration might be an effective way to prepare fine Mn-N-O catalysis. Magnetic measurements indicated that ferromagnetism and antiferromagnetism coexist within Mn2N0.86 at room temperature and that these magnetic properties are induced by nitrogen vacancies. Ab intio simulation was used to probe the nature of the magnetism in greater detail. The research contributes to the available data and the understanding of Mn2N0.86 and suggests ways to control the formation of materials based on Mn2N0.86.

Diabetic kidney disease (DKD) is a clinical syndrome that is one of the major causes of end-stage renal disease (ESRD). The pathogenesis of DKD is complex and multifaceted, with most studies indicating its association with genetics, advanced glycosylation end-product deposition, polyol pathway and protein C activation, lipid metabolism abnormalities, microcirculatory dysfunction, oxidative stress, inflammatory factors, and the kallikrein-kinin system. Epigenetics is the science studying gene expression regulation without changes in the DNA sequence. In recent years, increasing evidence has shown that epigenetic mechanisms play a crucial role in the initiation and progression of DKD. For instance, epigenetic modifications such as DNA methylation, histone modifications, and non-coding RNAs can influence the expression of DKD-related genes, thereby regulating the development and progression of DKD. On the other hand, metabolic memory is an important concept in DKD research. Metabolic memory refers to the phenomenon where cells maintain a certain metabolic state even after the disappearance of metabolic stress factors. This state can influence cell function and fate. In DKD, metabolic stress factors such as hyperglycemia can lead to metabolic memory in renal cells, affecting their function and fate, ultimately leading to the development and progression of DKD. Therefore, to further explore the pathogenesis of DKD, research on epigenetics should be strengthened, aiming to provide new ideas and methods for the prevention and treatment of DKD. [ABSTRACT FROM AUTHOR]

The East China Continental Margin (ECCM) is an exemplified natural laboratory not only for studying the origin and evolution of trench-arc-basin system, but also for investigating the deformation mechanism within continent and its margins. For a better understanding on the structure and evolution of the ECCM, a NW–SE trending onshore-offshore seismic profile was recently carried out there using controlled source wide-angle and passive broadband seismic experiments in combination. This 1050-km-long seismic profile transects the East China Sea Continental Shelf Basin (CSB), Zhemin Volcanic Belt, Lower Yangtze Block, and southern North China Craton from East China Sea to continental East China. Preliminary results, such as crustal reflected and refracted phases and P-wave receiver functions, show a good quality of the seismic data and tentatively delineate some first-order characteristics of the crustal structure of the ECCM. Expectably, more detailed crustal seismic velocity and geometric structures along the profile can be constructed by a further processing of the seismic data, and enable continuous and detailed comparisons of the crustal structure and inherent nature among different blocks, combined with other existing seismic profiles in the study region. And these further studies will provide reliable constraints on some controversial geologic issues, such as the origin of CSB, the contacting boundaries and collisional processes among Cathaysian Block, Yangtze and North China cratons. Keywords: Onshore-offshore seismic survey, Controlled source wide-angle seismic experiment, Passive broadband seismic experiment, Crustal structure, East China continental margin

Obtainment of hydrogen-rich metal hydrides that are high-temperature superconductors has been demonstrated under very high pressure, but is still largely unexplored. Here the authors synthesize CeH9, with a structure related to solid metallic hydrogen, at relatively low pressure and without need for heating.

New, stable stoichiometries in Be-P systems are investigated up to 100 GPa by the CALYPSO structure prediction method. Along with the BeP2-I41/amd structure, we identify two novel compounds of Be3P2-P-421m and Be3P2-C2/m. It should be noted that the Be-P compounds are predicted to be energetically unfavorable above 40 GPa. As can be seen, interesting structures may be experimentally synthesizable at modest pressure. Our results indicate that at 33.2 GPa, the most stable ambient-pressure tetragonal Be3P2-P-421m transitions to the monoclinic Be3P2-C2/m structure. Moreover, the predicted Be3P2-P-421m and Be3P2-C2/m phases are energetically favored compared with the Be3P2-Ia-3 structure synthesized experimentally. Electronic structure calculations reveal that BeP2-I41/amd, Be3P2-P-421m, and Be3P2-C2/m are all semiconductors with a narrow band gap. The present findings offer insight and guidance for exploration toward further fundamental understanding and potential applications in the semiconductor field.