spatial structure

空间结构
  • 文章类型: Journal Article
    了解物种分布和群落结构的空间变异是群落生态学的核心。然而,距离对元系统结构的影响还很少研究。我们研究了植物传粉者群落结构如何在区域范围内跨地理距离变化,并解开其潜在的本地和区域过程。我们使用多层网络来表示加那利群岛中相互联系的植物-传粉者社区作为元社区。我们使用模块化(即社区被划分为密集相互作用的物种组的程度)来量化跨空间结构中的距离衰减。在多层模块化中,同一物种可以属于不同社区的不同模块,和模块可以跨越社区。这使得能够量化模块组成中的相似性如何随岛之间的距离而变化。我们开发了三个空模型,每个控制多层网络的单独组件,解开物种周转的作用,结构中行驶距离衰减的相互作用重新布线和局部因素。我们在结构中发现了距离衰减的模式,表明随着距离的增加,岛屿倾向于共享更少的模块。物种周转(但不是相互作用重新布线)是触发结构距离衰减的主要区域过程。局部相互作用结构在确定区域尺度上的社区结构相似性方面也起着至关重要的作用。因此,确定在局部尺度上发生的物种相互作用的局部因素驱动距离在区域尺度上的结构衰减。我们的工作强调了社区结构背后的地方和区域过程之间的相互作用。方法论,特别是空模型,我们开发的提供了一个通用框架,用于连接空间中的社区,并测试有关生成空间结构的因素的不同假设。
    Understanding spatial variation in species distribution and community structure is at the core of community ecology. Nevertheless, the effect of distance on metacommunity structure remains little studied. We examine how plant-pollinator community structure changes across geographical distances at a regional scale and disentangle its underlying local and regional processes. We use a multilayer network to represent linked plant-pollinator communities as a metacommunity in the Canary Islands. We used modularity (i.e. the extent to which the community is partitioned into groups of densely interacting species) to quantify distance decay in structure across space. In multilayer modularity, the same species can belong to different modules in different communities, and modules can span communities. This enabled quantifying how similarity in module composition varied with distance between islands. We developed three null models, each controlling for a separate component of the multilayer network, to disentangle the role of species turnover, interaction rewiring and local factors in driving distance decay in structure. We found a pattern of distance decay in structure, indicating that islands tended to share fewer modules with increasing distance. Species turnover (but not interaction rewiring) was the primary regional process triggering distance decay in structure. Local interaction structure also played an essential role in determining the structure similarity of communities at a regional scale. Therefore, local factors that determine species interactions occurring at a local scale drive distance decay in structure at a regional scale. Our work highlights the interplay between local and regional processes underlying community structure. The methodology, and specifically the null models, we developed provides a general framework for linking communities in space and testing different hypotheses regarding the factors generating spatial structure.
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  • 文章类型: Journal Article
    大气冷等离子体(ACP)提出了一种有前途的方法,用于椰奶的灭菌,并表现出对椰子球蛋白(CG)的改性作用,椰奶中的主要过敏原。这项研究通过检查蛋白质结构的变化,研究了ACP治疗在减轻椰子汁变应原性方面的潜在作用。ACP治疗引起CG结构改变,破坏与免疫球蛋白E(IgE)的结合位点。因此,这导致CG和IgE之间的亲和力降低,Ka从2.17×104/M下降到0.64×104/M,从而减少IgE介导的过敏反应。来自变应原和细胞模型的发现进一步证实,ACP治疗使CG的变应原性降低了55.18%,同时抑制脱粒和过敏介质的释放。这项研究提出了一种生产低过敏性椰奶的创新方法,从而扩大了ACP技术在食品工业中的适用性。
    Atmospheric cold plasma (ACP) presents a promising method for the sterilization of coconut milk and exhibits a modifying effect on coconut globulin (CG), the primary allergen in coconut milk. This study investigated the potential role of ACP treatment in mitigating the allergenic properties of coconut milk by examining changes in protein structure. ACP treatment induced structural alterations in CG, disrupting binding sites with immunoglobulin E (IgE). Consequently, this led to a reduction in the affinity between CG and IgE, evidenced by a decrease in Ka from 2.17 × 104/M to 0.64 × 104/M, thereby diminishing IgE-mediated allergic reactions. The findings from allergenic and cellular models further corroborated that ACP treatment decreased the allergenicity of CG by 55.18%, while inhibiting degranulation and the release of allergic mediators. This study presents an innovative methodology for producing hypoallergenic coconut milk, thereby expanding the applicability of ACP technology within the food industry.
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  • 文章类型: Journal Article
    We analyzed age structure and dynamics, spatial distribution patterns, and reproductive capabilities of four Rosa persica populations in Xinjiang, to evaluate the survival status of the species and explore the reasons behind its endangerment. The results showed that the populations had fewer individuals in the youngest (Ⅰ) and oldest (Ⅵ-Ⅷ) age classes, with a predominance of middle-aged individuals, resulting in an irregular pyramid-shaped distribution, described as \"high in the middle, low on both sides\". The populations were generally growing, but were susceptible to external environmental disturbances (Vpi\'>0, Pmax>0). The mortality rate (qx) and vanish rate (Kx) peaked at age Ⅴ, leading to a sharp decline in plant abundance. The life expectancy (ex) decreased progressively with the increases of age class, reaching its lowest at age Ⅷ, which indicated minimal vitality at this stage. A time sequence analysis predicted a future dominance of individuals at age Ⅴ-Ⅷ, suggesting an aging trend. Spatially, the four populations were predominantly clumped, with the intensity of clumping ranked from highest to lowest as P4, P3, P1, and P2. P3 and P4 exhibited better reproductive capabilities than P1 and P2. There was a significant positive correlation between hundred-fruit weight and plant height and crown width, and between total seed number and crown width and hundred-fruit weight.
    以4个单叶蔷薇种群为研究对象,对年龄结构与动态、空间分布类型、结实能力3个方面进行分析,评价生存状况,探讨单叶蔷薇致危机理。结果表明: 单叶蔷薇种群第Ⅰ、Ⅵ~Ⅷ龄级个体数量较少,中间龄级个体数量较多,总体呈“中间高、两侧低”的不规则金字塔型分布。虽然4个单叶蔷薇种群整体上为增长型,但易受外部环境干扰(Vpi′>0,Pmax>0),死亡率(qx)和消失率(Kx)均在第Ⅴ龄级时达到最大值,植株数量锐减;期望寿命(ex)随龄级增加呈递减趋势,且均在第Ⅷ龄级时出现最小值,说明在此阶段植株活力最低。时间序列分析表明,未来4个单叶蔷薇种群的第Ⅰ~Ⅳ龄级个体数量缺乏,第Ⅴ~Ⅷ龄级将占主导地位,单叶蔷薇种群在未来会趋于老龄化。种群空间分布主要为聚集类型,4个种群的聚集强度大小排布为P4>P3>P1>P2。P3、P4种群植株结实能力优于P1、P2种群。百果重与株高、冠幅,种子总数量与冠幅、百果重之间呈显著正相关。.
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  • 文章类型: Journal Article
    宿主种群的社会和空间结构在病原体传播中起着重要作用。对于环境传播的病原体,宿主空间的使用与宿主社会结构和病原体的环境持久性(这决定了两个宿主可以传播的时差)相互作用。一起,这些因素塑造了环境传播病原体的流行病学动态。虽然社会和空间结构以及环境病原体持久性的重要性早已在流行病学中得到认可,它们通常被分开考虑。为了制定强有力的监测和管理策略,需要更好地了解这些因素如何相互作用以确定疾病动态。这里,我们使用一个简单的基于代理的模型,其中我们改变主机移动性(空间),宿主群居性(社会)和病原体腐烂(环境持久性),每个水平从低到高,以揭示它们如何影响流行病学动态。通过比较流行高峰,疫情高峰和最终疫情规模的时间,我们发现较长的感染期,更高的群体流动性,更大的群体规模和更长的病原体持久性导致更大的,更快的爆发,并探索这些过程如何相互作用,以确定流行病学结果,如流行高峰和最终流行规模。我们确定了可用于规划野生动物宿主病原体系统的监视和控制的一般原则,这些系统具有一系列空间行为的环境传播,社会结构和病原体腐烂率。本文是主题问题“空间-社会界面:理论和实证整合”的一部分。
    Social and spatial structures of host populations play important roles in pathogen transmission. For environmentally transmitted pathogens, the host space use interacts with both the host social structure and the pathogen\'s environmental persistence (which determines the time-lag across which two hosts can transmit). Together, these factors shape the epidemiological dynamics of environmentally transmitted pathogens. While the importance of both social and spatial structures and environmental pathogen persistence has long been recognized in epidemiology, they are often considered separately. A better understanding of how these factors interact to determine disease dynamics is required for developing robust surveillance and management strategies. Here, we use a simple agent-based model where we vary host mobility (spatial), host gregariousness (social) and pathogen decay (environmental persistence), each from low to high levels to uncover how they affect epidemiological dynamics. By comparing epidemic peak, time to epidemic peak and final epidemic size, we show that longer infectious periods, higher group mobility, larger group size and longer pathogen persistence lead to larger, faster growing outbreaks, and explore how these processes interact to determine epidemiological outcomes such as the epidemic peak and the final epidemic size. We identify general principles that can be used for planning surveillance and control for wildlife host-pathogen systems with environmental transmission across a range of spatial behaviour, social structure and pathogen decay rates. This article is part of the theme issue \'The spatial-social interface: a theoretical and empirical integration\'.
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  • 文章类型: Journal Article
    肿瘤内免疫浸润是影响非小细胞肺癌(NSCLC)免疫治疗反应的关键决定因素。然而,其表型和相关的空间结构仍然难以捉摸。为了克服这些限制,我们进行了一项综合研究,包括空间转录组(ST)数据(来自6个样本的28.712点).我们确定了两种不同的肿瘤内浸润模式:免疫排斥(以骨髓细胞为特征)和免疫激活(以浆细胞为特征)。免疫排斥和免疫激活特征在NSCLC患者的生存中显示出不利和有利的作用,分别。值得注意的是,CD14+APOE+细胞被认为是免疫排斥样本中的主要细胞类型。上皮间质转化增加,免疫活性降低。在ST和批量转录组学数据中观察到CD14+APOE+细胞和MMP7+肿瘤细胞的共定位,通过对20个非小细胞肺癌样本进行多重免疫荧光进行验证。共位区表现出增殖相关途径和缺氧活性的上调。这种共定位抑制了T细胞浸润和三级淋巴结构的形成。CD14+APOE+细胞和MMP7+肿瘤细胞均与较差的存活率相关。在ORIENT-3临床试验的免疫疗法队列中,不良反应的NSCLC患者表现出更高的CD14+APOE+细胞和MMP7+肿瘤细胞浸润。在同一地点区域内,MK,SEMA3和巨噬细胞迁移抑制因子(MIF)信号通路在细胞-细胞通讯中最为活跃。这项研究确定了NSCLC中的免疫排斥和激活模式以及CD14+APOE+细胞和MMP7+肿瘤细胞的共同定位是免疫抗性的贡献者。
    Intra-tumour immune infiltration is a crucial determinant affecting immunotherapy response in non-small cell lung cancer (NSCLC). However, its phenotype and related spatial structure have remained elusive. To overcome these restrictions, we undertook a comprehensive study comprising spatial transcriptomic (ST) data (28 712 spots from six samples). We identified two distinct intra-tumour infiltration patterns: immune exclusion (characterised by myeloid cells) and immune activation (characterised by plasma cells). The immune exclusion and immune activation signatures showed adverse and favourable roles in NSCLC patients\' survival, respectively. Notably, CD14+APOE+ cells were recognised as the main cell type in immune exclusion samples, with increased epithelial‒mesenchymal transition and decreased immune activities. The co-location of CD14+APOE+ cells and MMP7+ tumour cells was observed in both ST and bulk transcriptomics data, validated by multiplex immunofluorescence performed on 20 NSCLC samples. The co-location area exhibited the upregulation of proliferation-related pathways and hypoxia activities. This co-localisation inhibited T-cell infiltration and the formation of tertiary lymphoid structures. Both CD14+APOE+ cells and MMP7+ tumour cells were associated with worse survival. In an immunotherapy cohort from the ORIENT-3 clinical trial, NSCLC patients who responded unfavourably exhibited higher infiltration of CD14+APOE+ cells and MMP7+ tumour cells. Within the co-location area, the MK, SEMA3 and Macrophage migration inhibitory factor (MIF) signalling pathway was most active in cell‒cell communication. This study identified immune exclusion and activation patterns in NSCLC and the co-location of CD14+APOE+ cells and MMP7+ tumour cells as contributors to immune resistance.
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  • 文章类型: Journal Article
    该研究对比卡鲁胺的结构和构象进行了全面而详细的分析。量子化学计算用于探索分子的构象性质,识别构象异构体之间的显著能量差异。分析表明,氢键稳定了构象异构体,扭转角显着变化。根据循环片段的相对方向,将构象分为“封闭”和“开放”类型。在不同溶剂(CDCl3和DMSO-d6)中的NOE光谱用于研究分子的构象偏好。NOESY实验提供了非极性溶剂中“封闭”构象异构体的优势,以及极性溶剂中“开放”构象异构体的大量存在。CDCl3中开放构象的比例为22.7±3.7%,DMSO-d6中开放构象的比例为59.8±6.2%,而封闭构象的比例为77.3±3.7%和40.2±6.2%,分别。这项综合研究强调了溶剂环境对其结构行为的影响。这些发现大大有助于更深入地理解构象动力学,促进药物开发的进一步探索。
    The study presents a thorough and detailed analysis of bicalutamide\'s structural and conformational properties. Quantum chemical calculations were employed to explore the conformational properties of the molecule, identifying significant energy differences between conformers. Analysis revealed that hydrogen bonds stabilise the conformers, with notable variations in torsion angles. Conformers were classified into \'closed\' and \'open\' types based on the relative orientation of the cyclic fragments. NOE spectroscopy in different solvents (CDCl3 and DMSO-d6) was used to study the conformational preferences of the molecule. NOESY experiments provided the predominance of \'closed\' conformers in non-polar solvents and a significant presence of \'open\' conformers in polar solvents. The proportions of open conformers were 22.7 ± 3.7% in CDCl3 and 59.8 ± 6.2% in DMSO-d6, while closed conformers accounted for 77.3 ± 3.7% and 40.2 ± 6.2%, respectively. This comprehensive study underscores the solvent environment\'s impact on its structural behaviour. The findings significantly contribute to a deeper understanding of conformational dynamics, stimulating further exploration in drug development.
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  • 文章类型: Journal Article
    由于对空间结构和表面电荷特性的考虑不足,传统生物载体的微生物富集受到限制。这里,利用3D打印技术制造高分辨率材料的能力,我们进一步设计了一种带正电荷的海藻酸钠/ε-聚赖氨酸(SA/ε-PL)印刷油墨,构建了具有理想孔隙结构和丰富正电荷的3D打印生物载体,以增强微生物的富集。流变学和力学测试证实,开发的SA/ε-PL油墨可以同时满足打印过程的平滑挤出和3D结构的维护。ε-PL二次交联策略的利用增强了3D机械结构,并赋予了其作为生物载体应用所需的物理性质。与传统的海绵载体相比,3D打印生物载体具有更快的初始附着速率和更高的生物量,达到14.58±1.18VS/cm3,脱氮效率提高了53.9%。此外,由于优越的电化学性能和生物相容性,3D打印的生物载体有效地丰富了电活性反硝化细菌毛囊球菌属,从而支持其优异的脱氮性能。这项研究为废水处理中新型功能生物载体的开发提供了新的见解,从而为实际工程提供科学指导。
    The microbial enrichment of traditional biocarriers is limited due to the inadequate consideration of spatial structure and surface charging characteristics. Here, capitalizing on the ability of 3D printing technology to fabricate high-resolution materials, we further designed a positively charged sodium alginate/ε-poly-l-lysine (SA/ε-PL) printing ink, and the 3D printed biocarriers with ideal pore structure and rich positive charge were constructed to enhance the microbial enrichment. The rheological and mechanical tests confirmed that the developed SA/ε-PL ink could simultaneously satisfy the smooth extrusion for printing process and the maintenance of 3D structure. The utilization of the ε-PL secondary cross-linking strategy reinforced the 3D mechanical structure and imparted the requisite physical properties for its application as a biocarrier. Compared with traditional sponge carriers, 3D printed biocarrier had a faster initial attachment rate and a higher biomass of 14.58 ± 1.18 VS/cm3, and the nitrogen removal efficiency increased by 53.9 %. Besides, due to the superior electrochemical properties and biocompatibility, the 3D printed biocarriers effectively enriched the electroactive denitrifying bacteria genus Trichococcus, thus supporting its excellent denitrification performance. This study provided novel insights into the development of new functional biocarriers in the wastewater treatment, thereby providing scientific guidance for practical engineering.
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  • 文章类型: Journal Article
    宿主群体中多种病原体菌株的共存可能对疫苗开发或治疗功效提出重大挑战。在这里,我们讨论了一种新机制,可以提高长寿命菌株多态性的比率,植根于宿主人口中社会结构的存在。我们证明了互动的社会偏好,结合宿主亚群之间的免疫力差异,可以对病原体菌株施加不同的选择压力,创建支持稳定病毒共存的平衡机制,独立于其他已知机制。我们使用群体遗传模型来研究病原体杂合率作为群体大小的函数,宿主种群组成,突变株适应度差异与宿主社会偏好的相互作用。我们还表明,即使宿主种群分层的小周期周期也会导致菌株共存。这些结果对不同的社会互动偏好是稳健的,应变率的总体差异,和寄主种群组成的空间异质性。我们的结果强调了宿主群体社会分层在增加病原体菌株多样性中的作用,具有在设计具有遏制病原体进化的长期观点的政策或治疗时应该考虑的效果。
    Coexistence of multiple strains of a pathogen in a host population can present significant challenges to vaccine development or treatment efficacy. Here we discuss a novel mechanism that can increase rates of long-lived strain polymorphism, rooted in the presence of social structure in a host population. We show that social preference of interaction, in conjunction with differences in immunity between host subgroups, can exert varying selection pressure on pathogen strains, creating a balancing mechanism that supports stable viral coexistence, independent of other known mechanisms. We use population genetic models to study rates of pathogen heterozygosity as a function of population size, host population composition, mutant strain fitness differences and host social preferences of interaction. We also show that even small periodic epochs of host population stratification can lead to elevated strain coexistence. These results are robust to varying social preferences of interaction, overall differences in strain fitnesses, and spatial heterogeneity in host population composition. Our results highlight the role of host population social stratification in increasing rates of pathogen strain diversity, with effects that should be considered when designing policies or treatments with a long-term view of curbing pathogen evolution.
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  • 文章类型: Journal Article
    决定在何处觅食不仅必须考虑栖息地质量的变化,而且还必须考虑其他人可能在何处觅食。最近的研究表明,当人们记住最近的觅食结果时,负频率依赖学习可以使他们避免被他人利用的资源(间接竞争)。此过程可以推动在人口级别上出现资源使用(资源划分)的一致差异。然而,个人很难感觉到竞争的间接线索。这里,我们建议,通过集体决策,即集体智慧,信息汇集,可以使群体生活的动物种群相对于单独的动物种群更有效地分配资源。我们通过模拟(i)倾向于在最近成功的地方觅食的个体和(ii)使用多数规则选择一种资源的有凝聚力的群体来检验这一假设。虽然孤独的动物可以通过负频率依赖性学习部分避免间接竞争,在群居动物种群中更有可能出现资源分配。较大群体的人口也比较小群体的人口更好地分配资源,尤其是在有更多选择的环境中。我们的结果深入了解了长期记忆与短期记忆的价值,家庭范围的大小和专业化的演变,最佳的群体规模和地域性。本文是主题问题的一部分,“互联互动:通过空间和社会互动丰富食物网研究”。
    Deciding where to forage must not only account for variations in habitat quality but also where others might forage. Recent studies have suggested that when individuals remember recent foraging outcomes, negative frequency-dependent learning can allow them to avoid resources exploited by others (indirect competition). This process can drive the emergence of consistent differences in resource use (resource partitioning) at the population level. However, indirect cues of competition can be difficult for individuals to sense. Here, we propose that information pooling through collective decision-making-i.e. collective intelligence-can allow populations of group-living animals to more effectively partition resources relative to populations of solitary animals. We test this hypothesis by simulating (i) individuals preferring to forage where they were recently successful and (ii) cohesive groups that choose one resource using a majority rule. While solitary animals can partially avoid indirect competition through negative frequency-dependent learning, resource partitioning is more likely to emerge in populations of group-living animals. Populations of larger groups also better partition resources than populations of smaller groups, especially in environments with more choices. Our results give insight into the value of long- versus short-term memory, home range sizes and the evolution of specialization, optimal group sizes and territoriality. This article is part of the theme issue \'Connected interactions: enriching food web research by spatial and social interactions\'.
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  • 文章类型: Journal Article
    植物释放生物挥发性有机化合物(BVOCs)作为信号分子,在诱导对食草动物的抗性中起着至关重要的作用。窃听BVOC信号的邻近植物也可以增加对草食动物的防御或改变生长模式,以应对草食动物损害的潜在风险。尽管BVOC排放的重要性,它们释放背后的进化原理以及导致此类排放多样性的因素仍然知之甚少。为了解开BVOC排放演变的条件,我们开发了一个空间显式模型,形式化了BVOC排放和非排放策略的演化动力学。我们的模型考虑了影响植物适应度的BVOC信号的两个效应:个体内沟通,通过工厂自己的BVOC信号产生排放成本来减轻草食动物的损害,和个体间的交流,这改变了基于来自其他个体的BVOC信号的食草动物的影响,而不会产生排放成本。采用两个数学模型-晶格模型和随机分布模型-我们研究了个体内部沟通,个体间的交流,空间结构影响了BVOC排放策略的演变。我们的分析表明,个体内部交流的增加促进了BVOC排放策略的发展。相比之下,个体间交流效应的增加有利于骗子从邻近工厂释放的BVOCs中受益,而不承担与BVOC排放相关的成本。我们的分析还表明,BVOC信号的空间尺度越窄,BVOC演化的可能性越高。这项研究揭示了控制BVOC排放演变的复杂动力学及其对植物与植物交流的影响。
    Plants emit biogenic volatile organic compounds (BVOCs) as signaling molecules, playing a crucial role in inducing resistance against herbivores. Neighboring plants that eavesdrop on BVOC signals can also increase defenses against herbivores or alter growth patterns to respond to potential risks of herbivore damage. Despite the significance of BVOC emissions, the evolutionary rationales behind their release and the factors contributing to the diversity in such emissions remain poorly understood. To unravel the conditions for the evolution of BVOC emission, we developed a spatially explicit model that formalizes the evolutionary dynamics of BVOC emission and non-emission strategies. Our model considered two effects of BVOC signaling that impact the fitness of plants: intra-individual communication, which mitigates herbivore damage through the plant\'s own BVOC signaling incurring emission costs, and inter-individual communication, which alters the influence of herbivory based on BVOC signals from other individuals without incurring emission costs. Employing two mathematical models-the lattice model and the random distribution model-we investigated how intra-individual communication, inter-individual communication, and spatial structure influenced the evolution of BVOC emission strategies. Our analysis revealed that the increase in intra-individual communication promotes the evolution of the BVOC emission strategy. In contrast, the increase in inter-individual communication effect favors cheaters who benefit from the BVOCs released from neighboring plants without bearing the costs associated with BVOC emission. Our analysis also demonstrated that the narrower the spatial scale of BVOC signaling, the higher the likelihood of BVOC evolution. This research sheds light on the intricate dynamics governing the evolution of BVOC emissions and their implications for plant-plant communication.
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