Assessing intracellular and extracellular distribution of antibiotic resistance genes in the commercial organic fertilizers.

Compost-based organic fertilizers often contain high levels of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs). Previous studies focused on quantification of total ARGs and MGEs. For a more accurate risk assessment of the dissemination risk of antibiotic resistance, it is necessary to quantify the intracellular and extracellular distribution of ARGs and MGEs. In the present study, extracellular ARGs and MGEs (eARGs and eMGEs) and intracellular ARGs and MGEs (iARGs and iMGEs) were separately analyzed in 51 commercial composts derived from different raw materials by quantitative polymerase chain reaction (qPCR) and metagenomic sequencing. Results showed that eARGs and eMGEs accounted for 11-56% and 4-45% of the total absolute abundance of ARGs and MGEs, respectively. Comparable diversity, host composition and association with MGEs were observed between eARGs and iARGs. Contents of high-risk ARGs were similar between eARGs and iARGs, with high-risk ARGs in the two forms accounting for 6.7% and 8.2% of the total abundances, respectively. Twenty-four percent of the overall ARGs were present in plasmids, while 56.7% of potentially mobile ARGs were found to be associated with plasmids. Variation partitioning analysis, null model and neutral community model indicated that the compositions of both eARGs and iARGs were largely driven by deterministic mechanisms. These results provide important insights into the cellular distribution of ARGs in manure composts that should be paid with specific attention in risk assessment and management.

KAT7 enhances the proliferation and metastasis of head and neck squamous carcinoma by promoting the acetylation level of LDHA.

Lysine acetyltransferase 7 (KAT7), a histone acetyltransferase, has recently been identified as an oncoprotein and has been implicated in the development of various malignancies. However, its specific role in head and neck squamous carcinoma (HNSCC) has not been fully elucidated. Our study revealed that high expression of KAT7 in HNSCC patients is associated with poor survival prognosis and silencing KAT7 inhibits the Warburg effect, leading to reduced proliferation, invasion, and metastatic potential of HNSCC. Further investigation uncovered a link between the high expression of KAT7 in HNSCC and tumor-specific glycolytic metabolism. Notably, KAT7 positively regulates Lactate dehydrogenase A (LDHA), a key enzyme in metabolism, to promote lactate production and create a conducive environment for tumor proliferation and metastasis. Additionally, KAT7 enhances LDHA activity and upregulates LDHA protein expression by acetylating the lysine 118 site of LDHA. Treatment with WM3835, a KAT7 inhibitor, effectively suppressed the growth of subcutaneously implanted HNSCC cells in mice. In conclusion, our findings suggest that KAT7 exerts pro-cancer effects in HNSCC by acetylating LDHA and may serve as a potential therapeutic target. Inhibiting KAT7 or LDHA expression holds promise as a therapeutic strategy to suppress the growth and progression of HNSCC.

Clinical application of repetitive transcranial magnetic stimulation in improving functional impairments post-stroke: review of the current evidence and potential challenges.

In recent years, the stroke incidence has been increasing year by year, and the related sequelae after stroke, such as cognitive impairment, motor dysfunction, and post-stroke depression, seriously affect the patient's rehabilitation and daily activities. Repetitive transcranial magnetic stimulation (rTMS), as a safe, non-invasive, and effective new rehabilitation method, has been widely recognized in clinical practice. This article reviews the application and research progress of rTMS in treating different functional impairments (cognitive impairment, motor dysfunction, unilateral spatial neglect, depression) after stroke in recent years, and preliminary summarized the possible mechanisms. It has been found that the key parameters that determine the effectiveness of rTMS in improving post-stroke functional impairments include pulse number, stimulated brain areas, stimulation intensity and frequency, as well as duration. Generally, high-frequency stimulation is used to excite the ipsilateral cerebral cortex, while low-frequency stimulation is used to inhibit the contralateral cerebral cortex, thus achieving a balance of excitability between the two hemispheres. However, the specific mechanisms and the optimal stimulation mode for different functional impairments have not yet reached a consistent conclusion, and more research is needed to explore and clarify the best way to use rTMS. Furthermore, we will identify the issues and challenges in the current research, explore possible mechanisms to deepen understanding of rTMS, propose future research directions, and offer insightful insights for better clinical applications.

[Mechanism of pregnancy-induced thymus involution and regeneration and medication rules of postpartum prescriptions].

In order to prevent the maternal immune defenses to the semi-allogeneic fetus, the maternal body will present a special adaptive immune system change represented by acute thymic involution(ATI) during pregnancy, which can be quickly regenerated after delivery. The ATI during pregnancy is related to the level of sex hormones, which is mainly caused by progesterone. Pregnancy-induced ATI is manifested as the continuous shrinkage of thymus volume, especially the cortex, and the wrinkle and phagocytosis of the subcapsular cortical thymic epithelial cells(cTECs), while other thymic epithelial cells(TECs) remain unchanged. The postpartum thymus is regenerated by the co-mediation of forkhead box N1(FOXN1) as well as its target genes chemokine(C-C motif) ligand 25(CCL25), chemokine(C-X-C motif) ligand 12(CXCL12), δ-like ligand 4(DLL4), cathepsin L(CTSL), and serine protease 16(PRSS16). Once the postpartum thymus is poorly repaired, immune dysfunction of the maternal body and several puerperal diseases will be induced, seriously endangering the survival of the mother and the newborn. In traditional Chinese medicine(TCM), Qi and blood are the cornerstone of pregnancy, and the thymus plays a key role in regulating Qi and blood. The deficiency of Qi and blood during pregnancy and childbirth is closely related to the abnormal ATI during pregnancy and the poor regeneration of the postpartum thymus. Based on this theory, TCM has profound academic ideas and rich clinical experience in postpartum recuperation. Based on the systematic description of the mechanism of ATI regeneration during pregnancy, as well as data mining and analysis of two classic gynecological works of TCM, Wan's Gynecology and Fu Qing-zhu's Treatise on Gynecology, this study found that the commonly used TCM for postpartum included Angelicae Sinensis Radix, Ginseng Radix et Rhizoma, Glycyrrhizae Radix et Rhizoma, and Chuanxiong Rhizoma. Among them, Ginseng Radix et Rhizoma, Angelicae Sinensis Radix, and Chuanxiong Rhizoma are high-frequency TCMs with positive effects on postpartum recovery.However, the mechanism of these TCMs in promoting postpartum thymus regeneration needs further investigation.

Network pharmacology-based and molecular docking-based analysis of You-Gui-Yin for the treatment of osteonecrosis of the femoral head.

You-Gui-Yin (YGY) is a classic prescription for warming up kidney-Yang and filling in kidney essence in traditional Chinese medicine, and has been used to treat osteonecrosis of the femoral head (ONFH) effectively. However, the underlying mechanisms are still unknown. This study is aimed at exploring the possible mechanisms of action of the YGY in the treatment of ONFH based on network pharmacology and molecular docking. TCMSP was used to screen the active components and targets of YGY. The disease targets of ONFH were collected in several public databases. The protein-protein interaction (PPI) Network was constructed using the STRING platform. The Metascape database platform was used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The key active components and core target proteins of YGY in the treatment of ONFH were verified by the molecular docking. 120 active components were obtained from YGY, among which 73 components were hit by the 117 drug-disease intersection targets. Key effective components included quercetin, kaempferol, beta-sitosterol, glycitein, beta-carotene, and so on. Core target proteins included ALB, AKT1, TNF, IL6, TP53, and so on. According to GO and KEGG analyses, there were 1762 biological processes, 94 cellular component, 138 molecular function and 187 signaling pathways involved. we selected the top 20 biological processes (BP), cellular components (CC), molecular functions (MF) and signaling pathways to draw the heat maps, showing that Lipid and atherosclerosis signaling pathway, IL-17 signaling pathway, HIF-1 signaling pathway, relaxin signaling pathway and MAPK signaling pathway and other pathways may play a key role in the treatment of ONFH by YGY. The results of molecular docking showed that key effective components and corresponding core target proteins exhibited the good binding activity. YGY can treat ONFH through multicomponents, multitargets, and multipathways, which provides a reference for the subsequent research, development of targeted drugs and clinical application.

Causality between depression and ankylosing spondylitis in a European population: Results from a Mendelian randomization analysis.

The aim of this study was to explore the application of Mendelian randomization (MR) Egger and inverse variance weighted (IVW) in a causal effect on depression and ankylosing spondylitis (AS). Instrumental variables (IVs) were determined using genome-wide association studies. The 2-sample MR analysis was conducted by MR Egger to test the causal effect between depression and AS. The pleiotropy of potential instrumental variables was evaluated. The results of MR Egger and IVW were further compared. A total of 3 single nucleotide polymorphisms as the construct IVs were included. IVW results showed a significant causal effect between depression and AS (P < .001). Depression could promote the risk of AS (odds ratio = 1.060, 95% confidence interval: 1.026-1.094). However, the MR Egger showed no causal effect (P = .311). Heterogeneity statistics suggested that no heterogeneity was existed (P > .05). It was also suggested that there was no horizontal pleiotropy in IVs (MR Egger intercept: -0.0004, P = .471). Reverse MR analysis suggested that there was no causal effect between AS and depression (P > .05). Gene expression quantitative trait locus (QTLs) suggested that rs2517601 and RNF39 were positively correlated (beta = 1.066, P < .001). Depression may be one of the causes of AS by MR analysis in a European population. We can estimate the causal effect based on IVW when horizontal pleiotropy is very tiny.

Systematic Appraisal of Guidelines for the Diagnosis and Treatment of Choledocholithiasis.

BACKGROUND: To systematically evaluate the methodological quality of the current up-to-date guidelines pertaining to choledocholithiasis, we conducted a comprehensive analysis of key recommendations and corresponding evidence, focusing on the heterogeneity among these guidelines. METHOD: Systematic searches across various databases were performed to identify the latest guidelines. The identified guidelines, which met the inclusion criteria, underwent evaluation using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool. The key recommendations and evidence from the included guidelines were extracted and reclassified using the Oxford Centre for Evidence-Based Medicine (OCEBM) grading system, and the obtained results were analyzed. RESULTS: Nine guidelines related to choledocholithiasis were included in this study, out of which 4 achieved an overall standardized score of more than 60%, indicating their suitability for recommendation. Upon closer examination of the main recommendations within these guidelines, we discovered significant discrepancies concerning the utilization of similar treatment techniques for different diseases or different treatment methods under comparable conditions, and discrepancies in the recommended treatment duration. High-quality research evidence was lacking, and some recommendations either failed to provide supporting evidence or cited inappropriate and low-level evidence. CONCLUSION: The quality of guidelines pertaining to choledocholithiasis is uneven. Recommendations for the treatment of choledocholithiasis demonstrate considerable disparities among the guidelines, particularly regarding the utilization of endoscopic retrograde cholangiopancreatography as a treatment method and the management approaches for difficult stone cases. Improvements by guideline developers for these factors contributing to the heterogeneity would be a reasonable approach to further update the guidelines for cholangiolithiasis.

Developing an automatic warning system for anomalous chicken dispersion and movement using deep learning and machine learning.

Chicken is a major source of dietary protein worldwide. The dispersion and movement of chickens constitute vital indicators of their health and status. This is especially evident in Taiwanese native chickens (TNCs), a local variety which is high in physical activity when healthy. Conventionally, the dispersion and movement of chicken flocks are observed in patrols. However, manual patrolling is laborious and time-consuming. Moreover, frequent patrols increase the risk of carrying pathogens into chicken farms. To address these issues, this study proposes an approach to develop an automatic warning system for anomalous dispersion and movement of chicken flocks in commercial chicken farms. Embendded systems were developed to acquire videos of chickens from overhead view in a chicken house, in which approximately 20,000 TNCs were raised for a period of 10 wk. Each video was 5-min in length. The videos were transmitted to a remote cloud server and were converted into images. A You Only Look Once-version 7 tiny (YOLOv7-tiny) object detection model was trained to detect chickens in the images. The dispersion of the chicken flocks in a 5-min long video was calculated using nearest neighbor index (NNI). The movement of the chicken flocks in a 5-min long video was quantified using simple online and real-time tracking algorithm (SORT). The normal ranges (i.e., 95% confidence intervals) of chicken dispersion and movement were established using an autoregressive integrated moving average (ARIMA) model and a seasonal autoregressive integrated moving average with exogenous factors (SARIMAX) model, respectively. The system allows farmers to check up on the chicken farm only when the dispersion or movement values were not in the normal ranges. Thus, labor time can be saved and the risk of carrying pathogens into chicken farms can be reduced. The trained YOLOv7-tiny model achieved an average precision of 98.2% in chicken detection. SORT achieved a multiple object tracking accuracy of 95.3%. The ARIMA and SARIMAX achieved a mean absolute percentage error 3.71% and 13.39%, respectively, in forecasting dispersion and movement. The proposed approach can serve as a solution for automatic monitoring of anomalous chicken dispersion and movement in chicken farming, alerting farmers of potential health risks and environmental hazards in chicken farms.

Understory fuel loads and the impact factors of Quercus mongolica natural secondary forest in Hebei Pro-vince, China.

We investigated understory fuel loads of Quercus mongolica natural secondary forests in Hebei Province, China. We analyzed the effects of stand factors, topographic factors, and ground cover factors on the quantity and composition of fuel, established the dynamic models of understory fuel loads, and proposed management measures. The results showed that the understory total fuel load in Q. mongolica natural secondary forests was 11.68 t·hm-2, which exceeded the forest fire potential threshold (10 t·hm-2). The understory dead fuel load was mainly humus, and the understory living fuel load was mainly shrubs. The 1 h time-lag fuel load increased significantly with increasing canopy density, stand density, stand age, and litter thickness. The 10 h time-lag fuel load increased signi-ficantly with increasing stand density, average tree height, and litter thickness. Humus load decreased significantly with increasing altitude and increased significantly with increasing humus thickness. Herb load increased significantly with increasing sunny slope orientation and herbal coverage. Shrub load increased significantly with increasing slope degree, shrub coverage, and humus thickness. Understory total fuel load decreased significantly with increasing altitude, and increased significantly with increasing stand density, humus thickness, and litter thickness. The results of stepwise regression analysis indicated that stand density, humus thickness, and altitude could better predict the understory total fuel load (Radj2=0.775). Therefore, more attention should be paid on the control of stand density of Q. mongolica natural secondary forest in Hebei Province. Cleaning of litters and humus on the ground would help prevent forest fires scientifically and effectively.

Metabolomic and transcriptomic profiling reveals the effect of dietary protein and lipid levels on growth performance in loach (Paramisgurnus dabryanus).

The subject of this study was to explore the optimum requirements of loach (Paramisgurnus dabryanus) regarding dietary proteins and lipids and discuss the underlying mechanism. We designed nine diets to determine the effects of different levels of dietary crude protein (CP: 30%, 35%, and 40%) and ether extract (EE: 6%, 10%, and 14%) on the growth performance and metabolism of P. dabryanus. In total, 2160 healthy P. dabryanus (5.19 ± 0.01 g) were divided into nine groups with four replications at 60 fish per barrel stocking density. The trial lasted for eight weeks. Serum and liver samples were gathered for metabolomic and transcriptomic analyses. The results showed that the specific growth rate of P. dabryanus in the CP40EE10 group was the fastest and notably higher than that in other groups (P< 0.05). Analysis of the metabolome results found that the mTOR signaling pathway, glycerophospholipid metabolism, D-arginine and D-ornithine metabolism were significantly enriched pathways in the CP40EE10 group compared with the other groups (P< 0.05). Moreover, the transcriptomic analysis of differentially expressed genes (DEGs) showed that the expression of ARG (arginase) involved in protein synthesis was significantly upregulated in the CP40EE10 group compared to the slowest growing group (P< 0.05). Additionally, the expression of SPLA2 (secretory phospholipase A2) involved in lipid metabolism and FBP (fructose-1,6-bisphosphatase) involved in glucose metabolism were all significantly downregulated in the CP30EE6 group compared with the CP40EE10 group (P< 0.05). Furthermore, the analysis of differentially expressed metabolites (DEMs) and DEGs co-enriched in the KEGG pathway revealed that the significantly enriched pathways were arginine and proline metabolism, glycerophospholipid metabolism, and glycolysis/gluconeogenesis in CP40EE10 compared with other groups (P< 0.05). We conclude that including 40% CP and 10% EE in the P. dabryanus diet could result in a better growth rate. We hypothesized from metabolomic and transcriptomic analyses that the CP40EE10 diet might promote the growth of P. dabryanus by promoting protein synthesis, lipid metabolism, and energy production.

Palmitic acid/expanded graphite/CuS composite phase change materials toward efficient thermal storage and photothermal conversion.

In this study, an expanded graphite (EG) with nano-CuS (EG/CuS) support material with a special morphology was prepared, with EG/CuS filled with different ratios of palmitic acid (PA). Finally, a PA/EG/CuS composite phase change thermal storage material with photothermal conversion performance was synthesized. The superb chemical and thermal stability of PA/EG/CuS was demonstrated by characterization and analysis of the experiments. EG, a multi-layer structured material, provides rich binding sites for PA and nano-CuS and constructs rich thermal conductivity paths, which effectively improves the thermal conductivity of PA/EG/CuS. It is noted that the maximum thermal conductivity of PA/EG/CuS reached 0.372 W m-1 K-1 and the maximum phase change thermal storage capacity reached 260.4 kJ kg-1, which proved the excellent thermal storage properties of PA/EG/CuS. In addition, PA/EG/CuS exhibits excellent photothermal conversion performance, and the experimental results demonstrated that the best photothermal conversion efficiency of PA/EG/CuS reached 81.4%. The PA/EG/CuS developed in this study provides a promising method for fabricating excellent conductive and low leakage composite phase change materials for solar energy utilization and energy storage.

Evaluation and prediction of ecological carrying capacity in the Qilian Mountain National Park, China.

With increasing human impacts on the ecosystem in natural protected areas, there is an urgent need to undertake an assessment of ecological carrying capacity taken as a benchmark for assessing regional sustainability. Based on satellite remote sensing and socio-economic statistical data from 2000 to 2019, this study distinguished the controlling factors for the spatial and temporal patterns of ecological carrying capacity in the Qilian Mountain National Park, one of the 10 pilot national parks in China. The ecological carrying capacity index (ECCI) was developed by using the Driver-Pressure-State-Impact-Response framework and a comprehensive weight method. The results showed that the multiyear averaged ECCI was low in the south and west but was high in central and eastern regions. The spatial distribution of the ECCI was constrained by soil resources, ecosystem quality, land use/cover and water environment. At the regional scale, the ECCI decreased from 2000 to 2014, especially in Tianzhu, where farmland expansion and severe droughts reduced habitat quality and ecosystem function. However, the ECCI increased significantly from 2014 to 2019, which was attributed to a warm moist climate and the implementation of eco-environmental protection policies. Forest and grassland coverage, soil and water conservation, waste water treatment amount and terrestrial water reserves accounted for 35%, 26%, 20% and 8%, respectively, of the temporal variability in the ECCI. Concurrent with national park development, the ECCI is predicted to increase in most areas from 2020 to 2029 by back-propagation artificial neural networks, except for Sunan, Shandan and Menyuan, possibly owing to increasing conflicts between humans and the environment. The findings of this study provide evidence about the effectiveness of government policies in promoting regional sustainability by altering ecosystem composition and function. In addition, the dominant drivers for the temporal variability of ecological carrying capacity varied in space according to stepwise regression analysis, calling for region-specific management strategies in mountain protected areas and their surroundings.

Clinical Outcomes of Closed Reduction and External Fixation for Isolated Second Metacarpal Base Fracture-Dislocations.

OBJECTIVE: The isolated second metacarpal base fracture-dislocations in adults are rare, and the traditional main treatments include closed reduction with the plaster or splint and open reduction with internal fixation (ORIF). However, closed reduction with the plaster or splint is not solid enough and ORIF can damage the surrounding important tissues. The purpose of this study was to explore the clinical outcomes of closed reduction and external fixation (CREF) for the treatment of isolated second metacarpal base fracture-dislocations. METHODS: Ten patients who suffered isolated second metacarpal base fracture-dislocations between January 1, 2010, and February 1, 2020, were reviewed. All of the patients were treated by CREF. Radiographs and computed tomography scans were performed regularly after the operation. The grip and pinch strength, visual analog scale (VAS) pain score, American Society for Surgery of the Hand total active movement (TAM) and total active flexion (TAF) scores, Cooney score, Sollerman hand function test (SHFT) score, QuickDASH score, and range of motion of the index finger were recorded at the last follow-up visit to evaluate functional recovery; the injured and healthy hands were compared and we also recorded postoperative complications. The paired samples t-test was used to compare the healthy and injured sides. RESULTS: The patients were followed up for a median of 29.50 ± 4.2 months. There were no significant differences in the grip strength, pinch strength, angle of proximal interphalangeal joint (PIPJ) flexion, or angle of distal interphalangeal joint (DIPJ) flexion between the injured and healthy sides at the final follow-up visit (all p > 0.05). The mean TAM (268.20 ± 4.21) and TAF scores (270.60 ± 4.17) on injured side were significantly lower than those on healthy side (all p < 0.05). The mean Cooney score (93.50 ± 7.47) and SHFT score (78.50 ± 1.08) on injured side were lower, while the mean QuickDASH score (7.05 ± 3.11) on injured side was higher than those on healthy side (all p < 0.05). The mean VAS pain score was 0.50 ± 0.53 on injured side. There were no significant postoperative complications except for traumatic arthritis in one patient without obvious clinical symptoms. CONCLUSION: CREF achieves the satisfactory curative effect, and the patients obtain the good functional recovery without significant postoperative complications. CREF is a safe and effective treatment for isolated second metacarpal base fracture-dislocations with satisfactory clinical outcomes.

Multi-omics characterization of silent and productive HPV integration in cervical cancer.

Cervical cancer (CC) that is caused by high-risk human papillomavirus (HPV) remains a significant public health problem worldwide. HPV integration sites can be silent or actively transcribed, leading to the production of viral-host fusion transcripts. Herein, we demonstrate that only productive HPV integration sites were nonrandomly distributed across both viral and host genomes, suggesting that productive integration sites are under selection and likely to contribute to CC pathophysiology. Furthermore, using large-scale, multi-omics (clinical, genomic, transcriptional, proteomic, phosphoproteomic, and single-cell) data, we demonstrate that tumors with productive HPV integration are associated with higher E6/E7 proteins and enhanced tumor aggressiveness and immunoevasion. Importantly, productive HPV integration increases from carcinoma in situ to advanced disease. This study improves our understanding of the functional consequences of HPV fusion transcripts on the biology and pathophysiology of HPV-driven CCs, suggesting that productive HPV integration should be evaluated as an indicator of high risk for progression to aggressive cancers.

One-pot synthesis of liquid photocrosslinkable poly(l-lactide) with terminal triacrylate.

We synthesized a poly(l-lactide)-pentaerythritol triacrylate (PETA) polymer modified with acrylic trifunctional groups using a one-pot method based on ring-opening polymerization of l-lactide and PETA. We calculated the molecular weight and structure of PLA-PETA using gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) (1H, 13C, heteronuclear multiple bond correlation [HMBC]) spectroscopy. Photocrosslinking PLA-PETA using the Omnirad 1173 photoinitiator yielded a transparent sample with 91% crosslinkage. The crosslinked sample was analyzed using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and thermomechanical analysis (TMA) to determine its thermal properties and thermal expansion coefficient. In vitro cell toxicity tests showed an average cell viability >90%, indicating that the PLA-PETA polymer had good biocompatibility with cells after photocrosslinking.

Memory Effect on the Survival of Deinococcus radiodurans after Exposure in Near Space.

Near space (20 to 100 km in altitude) is an extreme environment with high radiation and extreme cold, making it difficult for organisms to survive. However, many studies had shown that there were still microbes living in this extremely harsh environment. It was particularly important to study which factors affected the survival of microorganisms living in near space after exposure to irradiation, as this was related to many studies, such as studies of radioresistance mechanisms, panspermia hypothesis, long-distance microbial transfer, and developing extraterrestrial habitats. Survival after radiation was probably influenced by the growth condition before radiation, which is called the memory effect. In this research, we used different growth conditions to affect the growth of Deinococcus radiodurans and lyophilized bacteria in exponential phase to maintain the physiological state at this stage. Then high-altitude scientific balloon exposure experiments were carried out by using the Chinese Academy of Sciences Balloon-Borne Astrobiology Platform (CAS-BAP) at Dachaidan, Qinghai, China (37°44'N, 95°21'E). The aim was to investigate which factors influence survival after near-space exposure. The results suggested that there was a memory effect on the survival of D. radiodurans after exposure. If the differences in growth rate were caused by differences in nutrition, the survival rate and growth rate were positively correlated. Moreover, the addition of paraquat and Mn2+ during the growth phase can also increase survival. This finding may help to deepen the understanding of the mechanics of radiation protection and provide relevant evidence for many studies, such as of long-distance transfer of microorganisms in near space. IMPORTANCE Earth's near space is an extreme environment with high radiation and extreme cold. Which factors affect the survival of microbes in near space is related to many studies, such as studies of radioresistance mechanisms, panspermia hypothesis, long-distance microbial transfer, and developing extraterrestrial habitats. We performed several exposure experiments with Deinococcus radiodurans in near space to investigate which factors influence the survival rate after near-space exposure; that is, there was a relationship between survival after radiation and the growth condition before radiation. The results suggested that there was a memory effect on the survival of D. radiodurans after exposure. This finding may help to deepen the understanding of the mechanism of radiation protection and provide relevant evidence for many studies, such as of long-distance transfer of microorganisms in near space.

A modified electromagnetic force calculation method has high accuracy and applicability for EMS maglev vehicle dynamics simulation.

The traditional electromagnetic force calculation method does not consider the non-linear magnetization characteristics of the ferromagnetic material or the magnetic resistance in full circuit, resulting in large calculation errors when the electromagnet operation state is far from the rated state, and causing the dynamics simulation results to diverge from the actual situation. A more accurate analytical formula for electromagnetic force is derived based on the full circuit magnetic resistance modification and considering the non-linear magnetization characteristics of ferromagnetic materials. Then combined with the finite element simulation analysis, the magnetic resistance modification (MRM) method is proposed for calculating electromagnetic levitation force and guiding force. This MRM method greatly improves the accuracy of electromagnetic force calculations and provides greater accuracy for EMS maglev vehicle dynamics simulations.

Sugars and sucrose transporters in pollinia of Phalaenopsis aphrodite (Orchidaceae).

The pollen grains of Phalaenopsis orchids are clumped tightly together, packed in pollen dispersal units called pollinia. In this study, the morphology, cytology, biochemistry, and sucrose transporters in pollinia of Phalaenopsis orchids were investigated. Histochemical detection was used to characterize the distribution of sugars and callose at the different development stages of pollinia. Ultra-performance liquid chromatography-high resolution-tandem mass spectrometry data indicated that P. aphrodite accumulated abundant saccharides such as sucrose, galactinol, myo-inositol, and glucose, and trace amounts of raffinose and trehalose in mature pollinia. We found that galactinol synthase (PAXXG304680) and trehalose-6-phosphate phosphatase (PAXXG016120) genes were preferentially expressed in mature pollinia. The P. aphrodite genome was identified as having 11 sucrose transporters (SUTs). Our qRT-PCR confirmed that two SUTs (PAXXG030250 and PAXXG195390) were preferentially expressed in the pollinia. Pollinia germinated in pollen germination media (PGM) supplemented with 10% sucrose showed increased callose production and enhanced pollinia germination, but there was no callose or germination in PGM without sucrose. We show that P. aphrodite accumulates high levels of sugars in mature pollinia, providing nutrients and enhanced SUT gene expression for pollinia germination and tube growth.