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Relict subtropical coniferous forests in China face severe fragmentation, resulting in declining populations, and some are under significant threat from invasive alien species. Despite the crucial importance of understanding forest dynamics, knowledge gaps persist, particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana. In this study, we investigated the impact of invasive plants on the regeneration of forests dominated by K. evelyniana, a subtropical relict species in southwestern China. For this purpose, we characterized forest dynamics of 160 forest plots featuring K. evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K. evelyniana. We identified four distinct forest types in which K. evelyniana was dominant. We found that radial growth of K. evelyniana trees is faster in younger age-classes today than it was for older trees at the same age. The population structure of K. evelyniana in each forest type exhibited a multimodal age-class distribution. However, three forest types lacked established saplings younger than 10 years old, a situation attributed to the dense coverage of the invasive alien Ageratina adenophora. This invasive species resulted in a reduction of understory species diversity. Additionally, our analysis uncovered a significant negative correlation in phylogenetic relatedness (net relatedness index) between native and invasive alien plant species in eastern Yunnan. This suggests closely related invasive species face heightened competition, hindering successful invasion. Taken together, our findings indicate that successful establishment and habitat restoration of K. evelyniana seedling/saplings require effective measures to control invasive plants.

Background: General surgeons play an important role in the provision of trauma care in Canada and the current extent of their trauma experience during training is unknown. We sought to quantify the operative and nonoperative educational experiences among Canadian general surgery trainees. Methods: We conducted a multicentre retrospective study of major operative exposures experienced by general surgery residents, as identified using institutional trauma registries and subsequent chart-level review, for 2008-2018. We also conducted a site survey on trauma education and structure. Results: We collected data on operative exposure for general surgery residents from 7 programs and survey data from 10 programs. Operations predominantly occurred after hours (73% after 1700 or on weekends) and general surgery residents were absent from a substantial proportion (25%) of relevant trauma operations. The structure of trauma education was heterogeneous among programs, with considerable site-specific variability in the involvement of surgical specialties in trauma care. During their training, graduating general surgery residents each experienced around 4 index trauma laparotomies, 1 splenectomy, 1 thoracotomy, and 0 neck explorations for trauma. Conclusion: General surgery residents who train in Canada receive variable and limited exposure to operative and nonoperative trauma care. These data can be used as a baseline to inform the application of competency-based medical education in trauma care for general surgery training in Canada. Contexte : Les chirurgiennes et chirurgiens g n ralistes jouent un r le important dans la prestation de soins de traumatologie au Canada, et l' tendue actuelle de leur exp rience en traumatologie durant la formation est inconnue. Nous avons voulu quantifier les exp riences p dagogiques op ratoires et non op ratoires chez les stagiaires en chirurgie g n rale du Canada. M thodes : Nous avons men une tude r trospective multicentrique sur les expositions op ratoires majeures que vivent les r sidentes et r sidents en chirurgie g n rale, rep r es dans les registres de traumatologie des tablissements et dans le cadre d'un examen subs quent des dossiers, pour la p riode de 2008-2018. Nous avons aussi men une enqu te sur la formation en traumatologie et la structure de celle-ci. R sultats : Nous avons recueilli des donn es sur l'exposition op ratoire des r sidentes et r sidents en chirurgie g n rale de 7 programmes ainsi que des donn es d'enqu te de 10 programmes. Les interventions chirurgicales avaient principalement lieu en dehors des heures normales (73% apr s 17h ou la fin de semaine), et les r sidentes et r sidents taient absents d'une proportion consid rable (25%) des interventions de traumatologie pertinentes. La structure de la formation sur le sujet tait h t rog ne entre les programmes, avec une importante variation d'un tablissement l'autre dans la participation des sp cialit s chirurgicales dans les soins de traumatologie. Durant leur formation, les r sidentes et r sidents en chirurgie g n rale qui terminaient leurs tudes avaient chacun particip environ 4 laparotomies initiales de traumatologie, 1 spl nectomie, 1 thoracotomie et 0 exploration du cou pour un trauma. Conclusion : Les r sidentes et r sidents en chirurgie g n rale form s au Canada sont expos s de fa on variable et limit e aux soins de traumatologie op ratoires et non op ratoires. Ces donn es peuvent servir de valeur de r f rence pour orienter l'application d'une formation m dicale fond e sur les comp tences en traumatologie dans la formation en chirurgie g n rale au Canada., Traumatic injury is the leading cause of death and disability for Canadians aged 1-44 years. (1) Care for the trauma patient is provided by a multitude of providers, most notably [...]

The Hawking evaporation of primordial black holes (PBH) reheats the Universe locally, forming hot spots that survive throughout their lifetime. We propose to use the temperature profile of such hot spots to calculate the decay rate of metastable vacua in cosmology, avoiding inconsistencies inherent to the Hartle-Hawking or Unruh vacuum. We apply our formalism to the case of the electroweak vacuum stability and find that a PBH energy fraction β>7×10−80(M/g)3/2 is ruled out for black holes with masses 0.8g

This research introduced a novel precast shear wall designed to address prevalent challenges encountered in precast shear wall structures, such as issues with difficult installation, high expenses, and the uncertain quality of grouting by eliminating the connection of the vertical distributing bars. Early experimental verification of this novel structural system showcased favourable results concerning its seismic performance. Building upon this groundwork, the paper presented an elaborate horizontal joint deformation model, demonstrating its precise analysis of damage modes and interface slip in the novel structural system with high reliability. Furthermore, in an effort to enhance the damage mode of this novel precast shear wall under conditions of low axial compression ratio, the study introduced and evaluated two improvement measures through finite element parametric analysis. The findings indicated a noticeable enhancement in capacity and a simultaneous reduction in interface slip with the proposed improvement measures. Additionally, the section steel measures were more effective than the additional bars measures.

[Objective] The aim of this study is to investigate the effects of different residue amounts on nitrogen utilization efficiency and losses. [Methods] The experiment involved five different residue amounts (0, 180, 360, 720, 1 440 kg/hm2) and two types of residues (polyethylene and biodegradable residues). Through pot experiments, the study examined the impact of different residue contents on soil total nitrogen, nitrogen gas losses, nitrogen fertilizer utilization efficiency, and tomato growth indicators. [Results] The research indicates that with an increase in residue content, the cumulative emissions of ammonia and nitrous oxide in the soil show a trend of first increasing and then decreasing. When the residue content reaches 720 kg/hm2, the cumulative ammonia emission significantly decreases by 11.31% to 13.70%, and nitrous oxide emission decreases by 4.74% to 5.13%. There was no significant difference in nitrogen residue in the soil. When the residue content is below 180 kg/hm2, the residue promotes tomato growth; when the residue content is above 180 kg/hm2, it inhibits tomato growth. Low residue content has no significant effect on nitrogen fertilizer utilization efficiency. However, when the content is higher than 360 kg/hm2, nitrogen fertilizer utilization efficiency shows a negative correlation with residue content. Through comprehensive analysis, it is suggested that soil residue content should be controlled within 180 kg/hm2 to avoid negative effects on crop growth. Furthermore, due to the degradable nature of biodegradable residues, their adverse effects on nitrogen absorption by plants and nitrogen fertilizer utilization efficiency are weaker than those of polyethylene residues. [Conclusion] Therefore, replacing polyethylene residues with biodegradable residues is considered feasible.

Higher derivative terms in the gravitational action are natural from the perspective of quantum gravity, but are perceived as leading to a lack of well-posedness. The Gauss–Bonnet term has second-order equations of motion, but does not impact gravitational dynamics in 4D, so one might expect that it is not physically relevant. We discuss how signatures can show up in tunnelling processes and whether these will likely be physically accessible in Higgs vacuum decay.

Female adults of the migratory locust, Locusta migratoria manilensis (Meyen), can sense seasonal photoperiod changes, which induces embryonic diapause as a key strategy to overwinter. Serine protease inhibitor genes (SPNs) were thought to play key roles during diapause, while few SPNs were functionally characterized. LmSPN2 was one of those genes differentially expressed between diapause and non-diapause eggs; however, its biological function remained to be explored. So, we conducted RNAi knockdown of LmSPN2, resulting in a significant decrease of the egg diapause rate by 29.7%. Using yeast two-hybrid assays, co-immunoprecipitation, and pull-down methods, we found an interaction between LmSPN2 and LmSPN3, which was proved to be mediated by a glutamate (E331) binding site of LmSPN2. RNAi knockdown of LmSPN3 resulted in a significant increase in diapause rate by 14.6%, indicating an inverse function of LmSPN2 and LmSPN3 on diapause regulation. Double knockdown of two SPN genes resulted in a 26.4% reduction in diapause rate, indicating that LmSPN2 was the dominant regulatory signal. Moreover, we found four Toll pathway genes (easter, spätzle, pelle, and dorsal) upregulated significantly after the knockdown of LmSPN2 while downregulated after the knockdown of LmSPN3. Therefore, we speculate that two SPNs regulate diapause through the Toll pathway. Our results indicated that LmSPN2 positively regulates locust egg entry into diapause, while LmSPN3 is a negative regulator of embryonic commitment to diapause. Their interaction is mediated by the binding site of E331 and influences egg diapause through the Toll pathway. This mechanistic understanding of diapause regulation expands our understanding of insect developmental regulation and provides functional targets for developing locust management strategies.

Promoting metallic magnesium (Mg)-based implants to treat bone diseases in clinics, such as osteosarcoma and bacterial infection, remains a challenging topic. Herein, an iron hydroxide-based composite coating with a two-stage nanosheet-like structure was fabricated on Mg alloy, and this was followed by a thermal reduction treatment to break some of the surface Fe–OH bonds. The coating demonstrated three positive changes in properties due to the defects. First, the removal of –OH made the coating superhydrophobic, and it had self-cleaning and antifouling properties. This is beneficial for keeping the implants clean and for anti-corrosion before implantation into the human body. Furthermore, the superhydrophobicity could be removed by immersing the implant in a 75% ethanol solution, to further facilitate biological action during service. Second, the color of the coating changed from yellow to brown-black, leading to an increase in the light absorption, which resulted in an excellent photothermal effect. Third, the defects increased the Fe2+ content in the coating and highly improved peroxidase activity. Thus, the defect coating exhibited synergistic photothermal/chemodynamic therapeutic effects for bacteria and tumors. Moreover, the coating substantially enhanced the anti-corrosion and biocompatibility of the Mg alloys. Therefore, this study offers a novel multi-functional Mg-based implant for osteosarcoma therapy.

Abstract Background Post-radiation nasopharyngeal necrosis (PRNN) is a severe adverse event following re-radiotherapy for patients with locally recurrent nasopharyngeal carcinoma (LRNPC) and associated with decreased survival. Biological heterogeneity in recurrent tumors contributes to the different risks of PRNN. Radiomics can be used to mine high-throughput non-invasive image features to predict clinical outcomes and capture underlying biological functions. We aimed to develop a radiogenomic signature for the pre-treatment prediction of PRNN to guide re-radiotherapy in patients with LRNPC. Methods This multicenter study included 761 re-irradiated patients with LRNPC at four centers in NPC endemic area and divided them into training, internal validation, and external validation cohorts. We built a machine learning (random forest) radiomic signature based on the pre-treatment multiparametric magnetic resonance images for predicting PRNN following re-radiotherapy. We comprehensively assessed the performance of the radiomic signature. Transcriptomic sequencing and gene set enrichment analyses were conducted to identify the associated biological processes. Results The radiomic signature showed discrimination of 1-year PRNN in the training, internal validation, and external validation cohorts (area under the curve (AUC) 0.713–0.756). Stratified by a cutoff score of 0.735, patients with high-risk signature had higher incidences of PRNN than patients with low-risk signature (1-year PRNN rates 42.2–62.5% vs. 16.3–18.8%, P

Abstract We investigate false vacuum decay catalysed by black holes under the influence of the higher order Gauss-Bonnet term. We study both bubble nucleation and Hawking-Moss types of phase transition in arbitrary dimension. The equations of motion of “bounce” solutions in which bubbles nucleate around arbitrary dimensional black holes are found in the thin wall approximation, and the instanton action is computed. The headline result that the tunnelling action for static instantons is the difference in entropy of the seed and remnant black holes is shown to hold for arbitrary dimension. We also study the Hawking-Moss transition and find a picture similar to the Einstein case, with one curious five-dimensional exception (due to a mass gap). In four dimensions, we find as expected that the Gauss-Bonnet term only impacts topology changing transitions, i.e. when vacuum decay removes the seed black hole altogether, or in a (Hawking-Moss) transition where a black hole is created. In the former case, topology changing transitions are suppressed (for positive GB coupling α), whereas the latter case results in an enhanced transition.

Abstract Sclerotinia sclerotiorum is a necrotrophic plant pathogenic fungus with broad distribution and host range. Bioactive compounds derived from plant extracts have been proven to be effective in controlling S. sclerotiorum. In this study, the mycelial growth of S. sclerotiorum was effectively inhibited by maleic acid, malonic acid, and their combination at a concentration of 2 mg/mL, with respective inhibition rates of 32.5%, 9.98%, and 67.6%. The treatment of detached leaves with the two acids resulted in a decrease in lesion diameters. Interestingly, maleic acid and malonic acid decreased the number of sclerotia while simultaneously increasing their weight. The two acids also disrupted the cell structure of sclerotia, leading to sheet-like electron-thin regions. On a molecular level, maleic acid reduced oxalic acid secretion, upregulated the expression of Ss-Odc2 and downregulated CWDE10, Ss-Bi1 and Ss-Ggt1. Differently, malonic acid downregulated CWDE2 and Ss-Odc1. These findings verified that maleic acid and malonic acid could effectively inhibit S. sclerotiorum, providing promising evidence for the development of an environmentally friendly biocontrol agent.