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Abstract Background To link the treatment of radiation injury with angiogenesis, and to design and seek a new therapeutic technique for the prevention and treatment of radiation injury. Methods The transverse bone transport device for rabbit mandible was designed and manufactured. Eighteen New Zealand white rabbits were randomly divided into a radiotherapy group and a normal group. The radiotherapy group received 18 Gy of radiation, and the device was implanted two weeks later. After a 7-day incubation period, transverse transportation was performed at a speed of 0.5 circles (0.4 mm) per day, with an 8-day cycle and a total traction distance of 3.2 mm. CBCT, Micro CT, and histological staining were employed to assess the dynamics of movement, osteogenesis, and angiogenesis. Results The transverse bone transport model of rabbit mandible was successfully established. CBCT revealed that the transport height in the normal and radiotherapy groups were 3.24 ± 0.17 mm and 3.22 ± 0.19 mm respectively. Micro CT analysis showed an increase in BV/TV and Tb.N over time, while Tb.Sp decreased; differences in BV/TV existed at 2 weeks but disappeared thereafter; differences in Tb.N and Tb.Sp persisted at 2 and 4 weeks. Histological staining using HE, Masson, and IHC demonstrated good bone maturity accompanied by rich neovascularization, and this was also confirmed by ImageJ software analysis. Conclusions The transverse bone transport was employed for the first time in the radiation-induced mandibular damage, thereby establishing a basis for further investigation into its clinical efficacy, application value, and underlying mechanisms. This breakthrough offers novel prospects for clinical interventions.

Abstract When the solar wind interacts with the ionosphere of an unmagnetized planet, it induces currents that form an induced magnetosphere. These currents and their associated magnetic fields play a pivotal role in controlling the movement of charged particles, which is essential for understanding the escape of planetary ions. Unlike the well-documented magnetospheric current systems, the ionospheric current systems driven by solar wind and atmospheric neutral winds have not been quantitatively observed, which constrains the quantification of energy transfer from stars to these planets. Here, utilizing eight years of data from the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission, we investigate the global distribution of ionospheric currents on Mars. We identify two distinct current systems in the ionosphere: one aligns with the solar wind electric field but exhibits hemispheric asymmetry perpendicular to the solar wind electric field direction; the other corresponds to the flow pattern of annually averaged neutral winds. We propose that these two current systems are driven by the solar wind and atmospheric neutral winds, respectively. Our findings reveal that Martian ionospheric dynamics are influenced by the neutral winds from below and the solar wind from above, highlighting the complex and intriguing nature of current systems on unmagnetized planets.

ObjectivesSingle-strand DNA-binding protein 1 (SSB1) plays a crucial role in the cellular response to DNA damage. This study aimed to explore the expression and regulation of SSB1 in normal rat salivary gland tissues and tissues following radiation, with a specific emphasis on its involvement in the repair of salivary gland injury.MethodsA total of 45 adult SD rats were randomly assigned to one control group or eight experimental groups. In the control group, five rats were euthanized without irradiation, and their parotid gland tissues were collected for analysis. The experimental groups received a dose of 6 Gy of radiation targeting the head and neck region; subsequently, five rats from each group were euthanized hly to collect parotid gland tissue samples, resulting in a total of eight experimental groups. The expression levels of SSB1, γ-H2AX, and PARP1 in the parotid gland tissues were assessed via immunohistochemistry, while changes in SSB1 gene expression were quantified via RT-qPCR.ResultsNo significant morphological differences were observed between the two groups following HE staining. In the immunohistochemistry (IHC) analysis, notable tissue-specific variation in SSB1 expression was identified, with higher levels detected in the ducts than in the acini and connective tissue. The expression of SSB1 gene initially increased post-radiation before subsequently decreasing, ultimately returning to baseline levels, as corroborated by the RT-qPCR results. In contrast, γ-H2AX and PARP1 exhibited minimal expression in the control group; however, their expression peaked at 1 h in the experimental group before gradually declining to levels comparable to those of the control group.ConclusionRadiation induces time-dependent upregulation of SSB1 expression in rat salivary glands, indicating that SSB1 may play a role in radiation-induced repair processes.

Suprathermal electrons are an important population of the Martian ionosphere, either produced by photoionization of atmospheric neutrals or supplied from the Solar Wind (SW). This study is dedicated to an in-depth investigation of the pitch angle distribution of suprathermal electrons at two representative energies, 19−55 eV and 124−356 eV, using the extensive measurements made by the Solar Wind Electron Analyzer on board the Mars Atmosphere and Volatile Evolution. Throughout the study, we focus on the overall degree of anisotropy, defined as the standard deviation of suprathermal electron intensity among different directions which is normalized by the mean omni-directional intensity. The available data reveal the following characteristics: (1) In general, low energy electrons are more isotropic than high energy electrons, and dayside electrons are more isotropic than nightside electrons; (2) On the dayside, the anisotropy increases with increasing altitude at low energies but remains roughly constant at high energies, whereas on the nightside, the anisotropy decreases with increasing altitude at all energies; (3) Electrons tend to be more isotropic in strongly magnetized regions than in weakly magnetized regions, especially on the nightside. These observations indicate that the anisotropy is a useful diagnostic of suprathermal electron transport, for which the conversion between the parallel and perpendicular momenta as required by the conservation of the first adiabatic invariant, along with the atmospheric absorption at low altitudes, are two crucial factors modulating the observed variation of the anisotropy. Our analysis also highlights the different roles on the observed anisotropy exerted by suprathermal electrons of different origins.

The heliospheric environment is very complex and filled with diverse high-energy particles from various origins, and among these particles, cosmic rays (CRs), including anomalous and Galactic components (ACRs and GCRs), are unique as they originate from beyond the solar system. Due to their stable and long-lasting presence in the heliosphere, the study of CRs is crucial for protecting humanity and other lifeforms against the hazards of high-energy radiation. In this work, we aim to study the prolonged changes in CR nitrogen, a fundamental element that constitutes amino acids, using the measurements from the Advanced Composition Explorer (ACE) spacecraft. The comparison of solar modulation on CR nitrogen and oxygen is also made using the yearly averaged ACE observations. The ACR nitrogen has a more even spectrum than ACR oxygen while the spectrum of GCR nitrogen is more abrupt than GCR oxygen. Further model results indicate that GCR nitrogen and oxygen undergo comparable modulation processes within the heliosphere and the slight difference between the observed power-law indices of nitrogen and oxygen spectrum is due to the distinct local interstellar spectrum of the two species. Besides, an analysis is made to explain the observed more flattened ACR spectrum of nitrogen than oxygen caused by the slightly different charge-to-mass ratio Z / A .

Understanding which processes control atmospheric escape and the loss of water from planetary environments is crucial. The ESA’s Venus Express spacecraft has observed a significant depletion in Venus’s upper atmosphere, driven by the solar wind. In such scenarios, the electromagnetic force can accelerate planetary ions to energies that allow them to escape from the planet. However, it is extremely challenging to directly measure electromagnetic forces on planetary ions. Here we present a 3D multifluid Hall–magnetohydrodynamics simulation model to investigate electromagnetic force terms and the effects of each term on solar wind plasma and planetary ions. We find that the total electromagnetic force reaches its peak near the bow shock and the magnetic pileup boundary, with obvious asymmetric characteristics, which slows down the solar wind plasma and compresses the heavy ions toward Venus. In addition, the morphology of the convection electric field force shows obvious north–south asymmetry, which leads to the formation of asymmetric structures and plasma flows in the Venusian magnetotail. The electromagnetic force patterns obtained by simulation are consistent with the results and speculation from observations, suggesting that the multifluid model developed here has substantial capacity in further analysis regarding planetary ion escape.

Idiopathic pulmonary fibrosis (IPF) is a progressive pulmonary disease that leads to interstitial inflammation, lung damage, and eventually life-threatening complications. Among various pathologic factors, Smad4 is a pivotal molecule involved in the progression and exacerbation of IPF. It mediates nuclear transfer of Smad2/Smad3 complexes and initiates the transcription of fibrosis-promoting genes. Thus, the inhibition of Smad4 expression in pulmonary fibroblasts by small interfering RNAs (siRNAs) might be a promising therapeutic strategy for IPF. Herein, we engineered exosome membranes (EM) by cationic lipid (i.e., DOTAP) to load siRNAs against Smad4 (DOTAP/siSmad4@EM), and investigated their specific delivery to pulmonary fibroblasts for treating IPF in a mouse model via pulmonary administration. As reference nanoscaffolds, undecorated DOTAP/siSmad4 complexes (lipoplexes, consisting of cationic lipid DOTAP and siRNAs) and siSmad4-loaded lipid nanoparticles (DOTAP/siSmad4@lipo, consisting of lipoplexes fused with DPPCChol liposomes) were also prepared. The results showed that DOTAP/siSmad4@EM exhibited a higher cellular uptake and gene silencing efficacies in mouse pulmonary fibroblasts (viz., MLg2908) as compared to the two reference nanoscaffolds. Furthermore, the outcomes of the in vivo experiments illustrated that DOTAP/siSmad4@EM could significantly down-regulate the Smad4 expression with augmented anti-fibrosis efficiency. Additionally, the DOTAP/siSmad4@EM conferred excellent biocompatibility with low cytokine levels in bronchoalveolar lavage fluid and proinflammatory responses in the pulmonary area. Taken together, the outcomes of our investigation imply that specific inhibition of Smad4 expression in pulmonary fibroblasts by pulmonary administrated DOTAP/siSmad4@EM is a promising therapeutic strategy for IPF, which could safely and effectively deliver siRNA drugs to the targeted site of action.

Abstract Message passing neural networks such as graph convolutional networks (GCN) can jointly consider various types of features for social bot detection. However, the expressive power of GCN is upper-bounded by the 1st-order Weisfeiler–Leman isomorphism test, which limits the detection performance for the social bots. In this paper, we propose a subgraph encoding based GCN model, SEGCN, with stronger expressive power for social bot detection. Each node representation of this model is computed as the encoding of a surrounding induced subgraph rather than encoding of immediate neighbors only. Extensive experimental results on two publicly available datasets, Twibot-20 and Twibot-22, showed that the proposed model improves the accuracy of the state-of-the-art social bot detection models by around 2.4%, 3.1%, respectively.

Abstract As the interplanetary magnetic field (IMF) carried by the solar wind encounters the martian atmosphere, it tends to pile up and drape around the planet, forming looping magnetic fields and inducing marsward ion flows on the nightside. Previous statistical observations revealed asymmetrical distribution features within this morphology; however, the underlying physical mechanism remains unclear. In this study, utilizing a three‐dimensional multi‐fluid magnetohydrodynamic simulation model, we successfully reproduce the asymmetrical distributions of the looping magnetic fields and corresponding marsward flows on the martian nightside. Analyzing the magnetic forces resulting from the bending of the IMF over the polar area, we find that the asymmetry is guided by the orientation of the solar wind motional electric field (ESW). A higher solar wind velocity leads to enhanced magnetic forces, resulting in more tightly wrapped magnetic fields with an increased efficiency in accelerating flows as they approach closer to Mars.

ObjectivesThe aim of this study was to extract radiomic features from vertebrobasilar artery calcification (VBAC) on head computed tomography (CT) images and investigate its diagnostic performance to identify culprit lesions responsible for acute cerebral infarctions.MethodsPatients with intracranial atherosclerotic disease who underwent vessel wall MRI (VW-MRI) and head CT examinations from a single center were retrospectively assessed for VBAC visual and textural analyses. Each calcified plaque was classified by the likelihood of having caused an acute cerebral infarction identified on VW-MRI as culprit or non-culprit. A predefined set of texture features extracted from VBAC segmentation was assessed using the minimum redundancy and maximum relevance method. Five key features were selected to integrate as a radiomic model using logistic regression by the Aikaike Information Criteria. The diagnostic value of the radiomic model was calculated for discriminating culprit lesions over VBAC visual assessments.ResultsA total of 1,218 radiomic features were extracted from 39 culprit and 50 non-culprit plaques, respectively. In the VBAC visual assessment, culprit plaques demonstrated more observed presence of multiple calcifications, spotty calcification, and intimal predominant calcification than non-culprit lesions (all p

Objective: Radiotherapy for head and neck can damage the salivary gland cells, which can easily result in xerostomia. No effective treatment for radiation-induced salivary gland dysfunction currently exists. Thus, we aimed to study the protective effect of Dicliptera chinensis polysaccharides (DCP) on the prevention of submandibular gland (SMG) cell damage caused by radiotherapy in Sprague-Dawley rats. Design: Mechanical enzyme digestion was used to extract primary rat SMG cells. A radiation injury model was established by treating these cells with a dose of 8 Gy, followed by intervention using different DCP concentrations. The cell counting kit 8 assay was used to determine the inhibition rate of SMG cells in each group. The rates of apoptosis and cell cycle progression were detected using flow cytometry. Expression of the Mre11/Rad50/Nbs1 complex (MRN) was detected using western blotting. Results: DCP increased the proliferation of SMG cells after irradiation, and cell growth activity positively correlated with polysaccharide concentration. Flow cytometry analysis of SMG cell apoptosis revealed that DCP markedly reduced the total apoptosis rate after irradiation, especially the early apoptosis rate. Cell cycle results suggested that DCP reduced the number of cells in the S and G2 phases after irradiation and alleviated the S and G2 blocks. Western blot results indicated that the expression of Mre11, Rad50, and Nbs1 decreased in the radiation-injured group, whereas their expression increased after DCP treatment. Conclusions: DCP can protect the rat SMG cells after radiation and be used as a protective agent against salivary gland cell damage caused by radiotherapy.

The gut is home to a large number of intestinal microbiota that play an important role in the metabolism and immune system of the host. A growing body of evidence suggests that a high-fat diet is closely associated with many metabolic disorders, including fatty liver and type 2 diabetes. According to reports, Tartary buckwheat extract has a positive effect on intestinal microbiota in animals. The effects of Tartary buckwheat on biochemical indexes and intestinal microflora in mice were studied. Tartary buckwheat protein (FGP), Tartary buckwheat resistant starch (FGS) and Tartary buckwheat flour (FGF) alleviated organ damage in mice and lowered the atherosclerotic index (AI) in plasma. Otherwise, principal coordinate analysis (PCoA) showed that intestinal bacterial structure of FGF were separated apparently from other groups. The Firmicutes/Bacteroidetes (F/B) value of the high-fat (HF)-FGF group was significantly lower than that of the HF-FGP and HF-FGS groups. FGF significantly increases the abundance of beneficial bacteria such as Bifidobacterium, while decreasing the abundance of lipopolysaccharide (LPS)-producing bacteria. Observation of blood lipid metabolism parameters and analysis of the intestinal microbiota suggested that FGF can be more effective than FGP and FGS to reduce the effects of a high-fat diet in mice, restoring the blood parameters to values similar of those in mice fed a low-fat diet. FGF may be used to prevent or treat blood lipid metabolism disorders and intestinal microbiota disorders in mice fed a high-fat diet.

Attributed to the lack of an Earth-like global intrinsic dipole magnetic field on Mars, the induced electromagnetic field environment plays a crucial role in the evolution of its atmosphere. The dominant motional electric field (EM) induced by the bulk motion of the magnetic field within the Martian magnetosheath serves to accelerate ions toward escape velocity, thereby forming a plume escape channel. However, the distribution morphology of EM itself has received limited attention in previous research. In this study, by taking advantage of the multi-fluid Hall-MHD model cooperating with the Martian crustal field model, we focus on elucidating the physical mechanisms underlying the asymmetrical distribution of EM and examining the influence of the crustal field on this asymmetry. The results obtained from the simulation conducted in the absence of the crustal field indicate that the EM is more intense within the −ZMSE magnetosheath, where EM is directed toward Mars, primarily due to its corresponding higher velocity and a stronger magnetic field at lower solar zenith angles. The Martian crustal field has the ability to enhance the local EM around the inner boundary of the magnetosheath by amplifying both the magnetic field and its associated velocity. Accordingly, these findings provide valuable insights into the asymmetric nature of EM within the Martian magnetosheath under typical quiet-time solar wind conditions.

Rice (Oryza sativa L.) is one of the most important food crops worldwide. However, during direct seeding, rice is extremely vulnerable to flooding stress, which impairs rice’s emergence and seedling growth and results in a significant yield loss. According to our research, chitosan oligosaccharides have the potential to be a chemical seed-soaking agent that greatly increases rice’s resistance to flooding. Chitosan oligosaccharides were able to enhance seed energy supply, osmoregulation, and antioxidant capacity, according to physiological index assessments. Using transcriptome and metabolomic analysis, we discovered that important differential metabolites and genes were involved in the signaling pathway for hormone synthesis and antioxidant capacity. Exogenous chitosan oligosaccharides specifically and significantly inhibit genes linked to auxin, jasmonic acid, and abscisic acid. This suggested that applying chitosan oligosaccharides could stabilize seedling growth and development by controlling associated hormones and reducing flooding stress by enhancing membrane stability and antioxidant capacity. Finally, we verified the effectiveness of exogenous chitosan oligosaccharides imbibed in seeds by field validation, demonstrating that they can enhance rice seedling emergence and growth under flooding stress.

Wavelike perturbations in the ionosphere of Titan, the largest satellite of Saturn, are explored based on the Cassini Ion Neutral Mass Spectrometer (INMS) measurements. Strong wavelike perturbations are identified for more than twenty ion species, from simple ones such as N+ and CH4+ to complex ones such as C2H3CNH+ and C4H7+. Simultaneous wavelike perturbations in background N2, indicative of atmospheric gravity waves, are also observed, motivating us to speculate that the INMS-derived ion perturbations are wave-driven. The amplitudes of the ion perturbations are found to be larger than that of the N2 perturbations. Clear compositional variation is revealed by the data: heavier ion species exhibit greater amplitudes. Such observations might be understood based on considerations either of force balance or chemical loss in Titan’s ionosphere.

Abstract To address the security risk caused by fixed offset mapping and the limited recoverability of random mapping used in image watermarking, a self‐embedding fragile image watermarking algorithm based on deneighbourhood mapping are proposed. First, the image is divided into several 2 × 2 blocks, and authentication watermark and recovery watermark are generated based on the average value of the image blocks. Then, the denighbourhood mapping is implemented as, for each image block, its mapping block is randomly selected outside its neighbourhood. Finally, the authentication watermark and the recovery watermark are embedded into the image block itself and its mapping block. Theoretical analysis indicates that in the case of continuous area tampering, the proposed watermarking algorithm can achieve a better recovery rate than that of the method based on the random mapping. The experimental results verify the rationality and effectiveness of the theoretical analysis. Moreover, compared with the existing embedding algorithms based on random mapping, chaos mapping, and Arnold mapping, in the case of continuous area tampering, the proposed algorithm also achieves a higher average recovery rate.

We investigate the seasonal variations of ion precipitation, utilizing observations from the Mars Atmosphere and Volatile Evolution mission spanning from 2014 January 4 to 2023 February 14. Our analysis reveals that a diminishing pattern characterizes the transition from Mars season L _s 0°–180° to Mars season L _s 180°–360°, manifesting as a reduction in precipitating ion fluxes. Additionally, we discern a significant influence of the crustal magnetic field on the seasonal variations in precipitating ion fluxes. Intriguingly, within regions where the crustal magnetic field exhibits a strong quasi-horizontal orientation, opposite seasonal trends become evident. The underlying physical mechanism driving these seasonal variations in ion precipitation is probably attributed to the mass loading effect that may decelerate the solar wind and influence the magnetic pileup. A detailed investigation is further demanded in the future.

Artificial intelligence approaches inspired by human cognitive function have usually single learned ability. The authors propose a multimodal foundation model that demonstrates the cross-domain learning and adaptation for broad range of downstream cognitive tasks.

Objective Evidence of therapy for dysfunctional coronary circulation in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI) is limited. This study was performed to compare the effects of atorvastatin and rosuvastatin on dysfunctional coronary circulation. Methods This retrospective study enrolled 597 consecutive patients with STEMI who underwent pPCI in 3 centers from June 2016 to December 2019. Dysfunctional coronary circulation was defined by the thrombolysis in myocardial infarction (TIMI) grade and the TIMI myocardial perfusion grade (TMPG). Logistic regression analysis was used to evaluate the impact of different statin types on dysfunctional coronary circulation. Results The incidence of TIMI no/slow reflow did not differ between the two groups, but the incidence of TMPG no/slow reflow was significantly lower in the atorvastatin than rosuvastatin group (44.58% vs. 57.69%, respectively). After multivariate adjustment, the odds ratio with 95% confidence interval of rosuvastatin was 1.72 (1.17–2.52) for after pretreatment TMPG no/slow reflow and 1.73 (1.16–2.58) for after stenting TMPG no/slow reflow. Atorvastatin and rosuvastatin showed no significant differences in clinical outcomes during hospitalization. Conclusions Compared with rosuvastatin, atorvastatin was associated with better coronary microcirculatory perfusion in patients with STEMI who underwent pPCI.

The plasma transport process is important for the ionosphere of Mars, which controls the structure of the ionosphere above an altitude of 200 km. Plasma transport from the dayside ionosphere is crucial for producing the nightside ionosphere on Mars. The alteration in dayside plasma transport in the presence of crustal fields may influence the distribution of Martian ionospheric plasma and plasma escape in the magnetotail. This study employed a three-dimensional multispecies magnetohydrodynamic (MHD) model to simulate Mars-solar wind interactions. We show the magnetic field distribution and plasma velocity variation on the Martian day-side. The results indicate that the ion transport from low- to high-solar-zenith-angle areas in the south is inhibited by crustal fields, leading to a reduction in the ion number density and a thinner ionosphere near the southern terminator. Many heavy ions remain in the southern dayside ionosphere rather than moving to the nightside. In addition, the maximum reduction in the tailward flux of the planetary ions calculated by the MHD simulation is more than 50% at the southern terminator, indicating an inhibitory effect of the crustal fields on day-to-night transport. These effects may lead to a reduction in ion number density in the southern nightside ionosphere. Finally, we demonstrate a decrease in the global heavy-ion loss rate.

Worries about the increasing number of Sybils in online social networks (OSNs) are amplified by a range of security issues; thus, Sybil detection has become an urgent real-world problem. Lightweight and limited data-friendly, LBP (Loopy Belief Propagation)-based Sybil-detection methods on the social graph are extensively adopted. However, existing LBP-based methods that do not utilize node attributes often assume a global or predefined homophily strength of edges in the social graph, while different user’s discrimination and preferences may vary, resulting in local homogeneity differences. Another issue is that the existing message-passing paradigm uses the same edge potential when propagating belief to both sides of a directed edge, which does not agree with the trust interaction in one-way social relationships. To bridge these gaps, we present SybilHP, a Sybil-detection method optimized for directed social networks with adaptive homophily prediction. Specifically, we incorporate an iteratively updated edge homophily estimation into the belief propagation to better adapt to the personal preferences of real-world social network users. Moreover, we endow message passing on edges with directionality by a direction-sensitive potential function design. As a result, SybilHP can better capture the local homophily and direction pattern in real-world social networks. Experiments show that SybilHP works with high detection accuracy on synthesized and real-world social graphs. Compared with various state-of-the-art graph-based methods on a large-scale Twitter dataset, SybilHP substantially outperforms existing methods.

In the Martian induced magnetosphere, the motion of planetary ions is significantly controlled by the ambient electric fields, which can be decomposed into three components: the motional, Hall, and ambipolar electric fields. Each of them is dominant in different regions and provides the ion acceleration with a particular effectiveness. Therefore, it is necessary to characterize the global distribution of these electric field components. In this study, a global multifluid Hall-MHD model is applied, which considers the motional, Hall, and ambipolar electric fields in ion transport and magnetic induction equations to self-consistently investigate the morphology of the electric fields in the Martian space environment. Numerical results suggest that the motional electric field is dominant in the upstream of the bow shock and in the magnetosheath along the Z _MSE direction, leading to the formation of the ion plume escape channel. At the bow shock, the ambipolar electric field points outward, to decelerate and deflect the solar wind plasma flow. In the magnetosheath region, the ambipolar and motional electric fields with inward direction tend to reaccelerate the solar wind ions. However, along the magnetic pileup boundary, the Hall electric field pointing outward prevents the solar wind ions from penetrating the Martian induced magnetosphere, which also prevails in the Martian magnetotail region, to accelerate the ions’ tailward escape. This is the first systematic investigation of the global distribution of electric fields, which is helpful to understand the processes of ion acceleration/deceleration and escape within the Mars–solar wind interaction.

Ionospheric chemistry plays an unexpectedly important role in the evolution of planetary habitability. This study is dedicated to a detailed modeling of the nightside Martian ionospheric structure and composition, a topic that has been poorly explored due to the absence of relevant measurements, but now becomes tractable owing to the unprecedented measurements made by the Mars Atmosphere and Volatile Evolution. Two-stream kinetic calculations and time-dependent fluid calculations are coupled to derive the nightside density profiles at 100–300 km for a large number of ion species, assuming solar wind electron precipitation as the only viable ionizing source in the ideal nonmagnetized atmosphere. Our calculations indicate the presence of a well-defined ionospheric peak at 146 km with a peak density of 8500 cm ^−3 , as driven by the strong atmospheric “absorption” of precipitating electrons at low altitudes. The distribution of nonterminal species is roughly under chemical equilibrium below 170 km, whereas for terminal species such as NO ^+ and HCO ^+ , diffusion is effective at essentially all altitudes, in direct contrast to the dayside behavior. In the more realistic magnetized atmosphere, the ionospheric peak seldom exists due to the patchiness of electron precipitation. In particular, our model results agree fairly well with the MAVEN measurements, especially in view of the coincidence between electron depletion and thermal plasma void seen along many MAVEN orbits. Compared to the dayside, the nightside ionospheric composition has a much higher proportion of NO ^+ and lower proportion of CO _2 ^+ , likely indicative of nightside enhancement of atmospheric O and N.

Owing to its unevenly distributed crustal fields, Mars acts as a unique obstacle to the solar wind. In the presence of the crustal fields, the transport of the planetary ions on the dayside ionosphere exhibits north–south asymmetry. Additionally, the heavy-ion loss in the magnetotail is affected by the crustal fields. In this paper, a three-dimensional multispecies magnetohydrodynamic model is employed to simulate Mars–solar wind interactions. Numerical results indicate that the meridional transport is dominant in most areas on the dayside ionosphere. In the presence of the crustal fields, the meridional transport on the southern hemisphere (southward transport) is reduced by more than 70% above the strong crustal sources, and the zonal velocity shows local changes inside strong and weak crustal field regions. These effects result in an increase or decrease in the number density of the heavy ions reaching the terminator, thereby influencing the thickness of the ionosphere. Decreased southward velocity leads to a reduction in the heavy-ion loss on the southern magnetotail. The radial outward flux is reduced by more than 30% for O _2 ^+ and CO _2 ^+ and by 10% for O ^+ . This study shows that in addition to the zonal transport, the meridional transport is important for the day-to-night transport on the dayside of Mars. Collectively, the horizontal plasma transport, controlled by crustal fields, is associated with the altered ionosphere structure and reduced heavy-ion loss in the magnetotail.

As an unmagnetized planet, Venus does not have a global dipole magnetic field like Earth. The solar wind interacts directly with the Venusian ionosphere. In this paper, the interaction between solar wind and the Venusian upper atmosphere is investigated by conducting a three-dimensional multispecies magnetohydrodynamic (MHD) model, in which the Venusian ionosphere is developed self-consistently by considering chemical reactions among four major ion species (H ^+ , O _2 ^+ , O ^+ , and CO _2 ^+ ). Based on this developed MHD model, we mainly study the effects of the impulsive solar wind dynamic pressure on the interaction process. Simulation results reveal that the locations of the bow shock and magnetic pileup boundary show an abrupt compression, then expansion, and finally shrinkage to reach a new steady state with the influence of the impulsive dynamic pressure. The recovery time of the large-scale magnetic field is a few minutes. In addition, the peak escape fluxes are enhanced by about 1 order of magnitude due to the increased solar wind dynamic pressure pulse.

Different boundaries could be defined in a planetary ionosphere where the dominant process in function switches from one to the other. Identifying these boundaries and understanding their variations are hence crucial for disentangling the complexity of the ionosphere. Focusing on Mars, we perform a data-driven analysis of various boundaries and the associated time constants based on the multi-instrument measurements made by the Mars Atmosphere and Volatile Evolution mission during six campaigns that sample broadly different internal and external conditions. The boundaries we investigate include the photochemical equilibrium (PCE) boundary, the magnetic frozen boundary, the ion collision boundary, and the ion gyration boundary. Our analysis reveals systematic solar cycle and diurnal variations in that all boundaries tend to be elevated at enhanced solar activity and on the dayside and duskside of Mars. The variations with the magnetic environment are not observed for all boundaries except for the PCE boundary that exhibits an obvious elevation in strongly magnetized regions. Finally, our analysis suggests interesting species-dependent variations of different boundaries. In particularly, the PCE boundary shows the largest variability among all, with reduced boundary locations for all terminal species (NO ^+ , HCO ^+ , ${{\rm{O}}}_{2}^{+}$ , and H _3 O ^+ ) and one extra nonterminal species (CO _2 ^+ ) owing to different chemical properties rendered by different ions.

Rice (Oryza sativa L.) is one of the most significant food crops worldwide. Flooding can significantly impact the survival and emergence of rice seedlings in the direct planting form of rice, leading to a loss of production. This work investigated the critical phase of rice seed germination to the seedling establishment under submergence stress. It also explored the underlying physiological and molecular processes of shoot and root submergence tolerance. Physiological and transcriptomic analysis of flood-tolerant varieties (LS273) and non-flood-tolerant varieties (ZZ39) were performed. Under submergence stress, LS273 showed longer roots, taller shoots than ZZ39, and lower levels of malondialdehyde and GSSG, but a greater level of GSH/GSSG. In response to stress induced by submersion, LS273 produces more auxin than ZZ39. Within shoots, 4285 DEGs specific to LS273 and 4389 DEGs specifics to ZZ39 were found using the RNA-seq technique. There were 3983 specific DEGs in LS273 and 3292 specific DEGs in ZZ39 in the roots. Antioxidants and plant growth hormones were primarily mentioned in the annotations for these DEGs. Overall, our research provides a thorough foundation for investigating the molecular network underlying shoots’ and roots’ resistance to submergence stress in rice seedlings, leading us to hypothesize that the resistance of flood-tolerant rice may be attributed to high levels of oxidation resistance and auxin accumulation.

Significant genetic association exists between rheumatoid arthritis (RA) and cardiovascular disease. The associated mechanisms include common inflammatory mediators, changes in lipoprotein composition and function, immune responses, etc. However, the causality of RA and vascular/heart problems remains unknown. Herein, we performed Mendelian randomization (MR) analysis using a large-scale RA genome-wide association study (GWAS) dataset (462,933 cases and 457,732 controls) and six cardio-cerebrovascular disease GWAS datasets, including age angina (461,880 cases and 447,052 controls), hypertension (461,880 cases and 337,653 controls), age heart attack (10,693 cases and 451,187 controls), abnormalities of heartbeat (461,880 cases and 361,194 controls), stroke (7,055 cases and 454,825 controls), and coronary heart disease (361,194 cases and 351,037 controls) from United Kingdom biobank. We further carried out heterogeneity and sensitivity analyses. We confirmed the causality of RA with age angina (OR = 1.17, 95% CI: 1.04–1.33, p = 1.07E−02), hypertension (OR = 1.45, 95% CI: 1.20–1.75, p = 9.64E−05), age heart attack (OR = 1.15, 95% CI: 1.05–1.26, p = 3.56E−03), abnormalities of heartbeat (OR = 1.07, 95% CI: 1.01–1.12, p = 1.49E−02), stroke (OR = 1.06, 95% CI: 1.01–1.12, p = 2.79E−02), and coronary heart disease (OR = 1.19, 95% CI: 1.01–1.39, p = 3.33E−02), contributing to the understanding of the overlapping genetic mechanisms and therapeutic approaches between RA and cardiovascular disease.

A three-dimensional four species multi-fluid magnetohydrodynamic (MHD) model was constructed to simulate the solar wind global interaction with Mars. The model was augmented to consider production and loss of the significant ion species in the Martian ionosphere, i.e., H+, O2+, O+, CO2+, associated with chemical reactions among all species. An ideal dipole-like local crustal field model was used to simplify the empirically measured Martian crustal field. Results of this simulation suggest that the magnetic pile-up region (MPR) and the velocity profile in the meridian plane are asymmetric, which is due to the nature of the multi-fluid model to decouple individual ion velocity resulting in occurrence of plume flow in the northern Martian magnetotail. In the presence of dipole magnetic field model, boundary layers, such as bow shock (BS) and magnetic pile-up boundary (MPB), become protuberant. Moreover, the crustal field has an inhibiting effect on the flux of ions escaping from Mars, an effect that occurs primarily in the region between the terminator (SZA 90°) and the Sun–Mars line of the magnetotail (SZA 180°), partially around the terminator region. In contrast, near the tailward central line the crustal field has no significant impact on the escaping flux.

Digital signature and watermarking are effective image copyright protection techniques. However, these methods come with some inherent drawbacks, including the incapacity of carrying information and inevitable fidelity loss, respectively. To improve this situation, this paper proposes a neural network-based image batch copyright protection scheme, with which a copyright message bitstream can be extracted from each registered image while no modifications are introduced. Taking advantage of the pattern extraction capability and the error tolerance of the neural network, the proposed scheme achieves perfect imperceptibility and superior robustness. Moreover, the network's preference for diverse data content makes it especially appropriate for multiple images copyright verification. These claims will be further supported by the experimental results in this paper.

The etiology of non-alcoholic fatty liver disease (NAFLD) involves complex interaction of genetic and environmental factors. A large number of observational studies have shown that hypothyroidism contributes to a high risk of NAFLD. However, the exact causality is still unknown. Due to the progress of genome-wide association study (GWAS) and the discovery of Mendelian randomization (MR), it is possible to explore the causality between the two diseases. In this study, in order to research into the influence of intermediate phenotypes on outcome, nine independent genetic variants of hypothyroidism obtained from the GWAS were used as instrumental variables (IVs) to perform MR analysis on NAFLD. Since there was no heterogeneity between IVs (P = 0.70), a fixed-effects model was used. The correlation between hypothyroidism and NAFLD was evaluated by using inverse-variance weighted (IVW) method and weighted median method. Then the sensitivity test was analyzed. The results showed that there was a high OR (1.7578; 95%CI 1.1897–2.5970; P = 0.0046) and a low intercept (−0.095; P = 0.431). None of the genetic variants drove the overall result (P < 0.01). Simply, we proved for the first time that the risk of NAFLD increases significantly on patients with hypothyroidism. Furthermore, we explained possible causes of NAFLD caused by hypothyroidism.

Background. Diabetes mellitus (DM) and dyslipidemia are the main risk factors for atherosclerosis. Elevated glycosylated hemoglobin A1c (HbA1c) and reduced high-density lipoprotein cholesterol (HDL-C) are associated with the progression of atherosclerosis. The aim of this study is at exploring the relationship between the HbA1c/HDL-C ratio and atherosclerosis evaluated using carotid artery intima-media thickness (cIMT) and carotid artery plaque. Methods. In this retrospective study, we enrolled 1304 patients who had multiple cardiovascular risk factors or symptoms of suspected coronary artery disease. cIMT and carotid artery plaque were measured using ultrasonography. Logistic regression was used to explore the correlation between the HbA1c/HDL-C ratio and cIMT or carotid artery plaque. We used restricted cubic spline curves to assess nonlinear relationships between the HbA1c/HDL-C ratio and cIMT or carotid artery plaque. Results. With increased quartiles of HbA1c/HDL-C, patients had higher cIMT and a greater carotid plaque burden. After adjusting for other relevant clinical covariates, patients with the highest HbA1c/HDL-C ratio (quartile 4 (Q4)) had a 2.88 times (95% confidence interval (CI): 2.02–4.10, P

Computational methods that predict protein stability changes induced by missense mutations have made a lot of progress over the past decades. Most of the available methods however have very limited accuracy in predicting stabilizing mutations because existing experimental sets are dominated by mutations reducing protein stability. Moreover, few approaches could consistently perform well across different test cases. To address these issues, we developed a new computational method PremPS to more accurately evaluate the effects of missense mutations on protein stability. The PremPS method is composed of only ten evolutionary- and structure-based features and parameterized on a balanced dataset with an equal number of stabilizing and destabilizing mutations. A comprehensive comparison of the predictive performance of PremPS with other available methods on nine benchmark datasets confirms that our approach consistently outperforms other methods and shows considerable improvement in estimating the impacts of stabilizing mutations. A protein could have multiple structures available, and if another structure of the same protein is used, the predicted change in stability for structure-based methods might be different. Thus, we further estimated the impact of using different structures on prediction accuracy, and demonstrate that our method performs well across different types of structures except for low-resolution structures and models built based on templates with low sequence identity. PremPS can be used for finding functionally important variants, revealing the molecular mechanisms of functional influences and protein design. PremPS is freely available at https://lilab.jysw.suda.edu.cn/research/PremPS/, which allows to do large-scale mutational scanning and takes about four minutes to perform calculations for a single mutation per protein with ~ 300 residues and requires ~ 0.4 seconds for each additional mutation.

Summary: Missense mutations may affect proteostasis by destabilizing or over-stabilizing protein complexes and changing the pathway flux. Predicting the effects of stabilizing mutations on protein-protein interactions is notoriously difficult because existing experimental sets are skewed toward mutations reducing protein-protein binding affinity and many computational methods fail to correctly evaluate their effects. To address this issue, we developed a method MutaBind2, which estimates the impacts of single as well as multiple mutations on protein-protein interactions. MutaBind2 employs only seven features, and the most important of them describe interactions of proteins with the solvent, evolutionary conservation of the site, and thermodynamic stability of the complex and each monomer. This approach shows a distinct improvement especially in evaluating the effects of mutations increasing binding affinity. MutaBind2 can be used for finding disease driver mutations, designing stable protein complexes, and discovering new protein-protein interaction inhibitors. : Protein Folding; Bioinformatics; 3D Reconstruction of Protein Subject Areas: Protein Folding, Bioinformatics, 3D Reconstruction of Protein