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BackgroundAlthough social rejection is among the strongest proximal precipitants of major depressive disorder (MDD), little is known about the underlying neurobiological mechanisms and whether neural sensitivity to social rejection may help explain differences in MDD risk. To address this issue, we tested whether neural responses to social threat differed in female adolescents at high vs. low maternal risk for MDD.MethodFemale adolescents with (high-risk; n = 22, Mage = 14.68) and without (low-risk; n = 30, Mage = 15.07) a maternal history of depression were experimentally exposed to negative and neutral social evaluation while undergoing an fMRI scan. Neural responses were assessed by event-related activity and functional connectivity, as well as multivoxel pattern analysis. Activity and functional connectivity analyses focused on a priori-selected regions of interest implicated in self-referential processing and emotion regulation.ResultsCompared to low-risk female adolescents, high-risk female adolescents exhibited greater increases in self-reported depression and social disconnection following social evaluation. Moreover, compared to low-risk female adolescents, high-risk female adolescents exhibited greater amygdala responses to negative social evaluation and a differential pattern of functional connectivity in brain regions related to emotion regulation, self-referential processing, and negative affect. Additionally, these markers of neural threat reactivity were related to depressive symptoms.LimitationsA cross-sectional study design and relatively small, Western sample.ConclusionsThese results suggest that exaggerated neural reactivity to social threat-and an atypical pattern of related functional connectivity-is evident in individuals with a preclinical risk factor for depression. Targeting such responding may thus be a fruitful strategy for preventing depression in at-risk youth.

Street networks allow people and goods to move through cities, but they are vulnerable to disasters like floods, earthquakes, and terrorist attacks. Well-planned network design can make a city more resilient and robust to such disruptions, but we still know little about worldwide patterns of vulnerability, or worldwide empirical relationships between specific design characteristics and resilience. This study quantifies and measures the vulnerability of the street networks of every urban area in the world then models the relationships between vulnerability and street network design characteristics. To do so, we simulate over 2.4 billion trips across more than 8,000 urban areas in 178 countries, while also simulating network disruption events representing floods, earthquakes, and targeted attacks. We find that disrupting high-centrality nodes severely impacts network function. All else equal, networks with higher connectivity, fewer chokepoints, or less circuity are less vulnerable to disruption's impacts. This study thus contributes a new global understanding of network design and vulnerability to the literature. We argue that these design characteristics offer high leverage points for street network resilience and robustness that planners should emphasize when designing or retrofitting urban networks.

In this paper, we focus on examining the K 1 , 2 -structure-connectivity of any connected graph. Let G be a connected graph with n vertices, we show that κ (G ; K 1 , 2) is well defined if diam (G) ≥ 4 , or n ≡ 1 (mod 3) , or G ∉ { C 5 , K n } when n ≡ 2 (mod 3) , or there exist three vertices u, v, w such that N G (u) ∩ (N G ({ v , w }) ∪ { v , w }) = ∅ when n ≡ 0 (mod 3) . Furthermore, if G has K 1 , 2 -structure-cut, we prove κ (G) / 3 ≤ κ (G ; K 1 , 2) ≤ κ (G) . [ABSTRACT FROM AUTHOR]

Diagnosability is a fundamental consideration when designing an interconnected network. The PMC and MM ∗ fault diagnosis models are the two most commonly used models. Both the g -good-neighbour diagnosability and g -extra diagnosability of an interconnection network have been two of the hot topics in the intersectional research areas of Graph theory and Computer Science, which become increasingly attractive for new solutions to real-world problems. However, there are still some problems in the transformation from the concepts of Computer Science to that of mathematics. In this paper, we systematically study such problems and give a strict proof from concepts to mathematical conclusions. In the terms of results, we not only give the relationship between g -good-neighbour diagnosabilities of the network under PMC model and MM ∗ model, but also between g -extra diagnosabilities of the network under PMC and MM ∗ models. To apply our results, we give an application on the enhanced hypercube in the end and derive a lemma explaining whether these are 3-cycles in enhanced hypercubes and how many common neighbours for two vertices of enhanced hypercubes under different values of k in the meantime. [ABSTRACT FROM AUTHOR]

Let G be a graph with vertex set V (G) and S ⊆ V (G). An S -path of G is a path which connects all vertices of S in G. Let P 1 and P 2 be S -paths. If E (P 1) ∩ E (P 2) = 0̸ and V (P 1) ∩ V (P 2) = S , then the two paths P 1 and P 2 are called internally disjoint S - paths. Denoted by π G (S) the maximum number of any pairwise internally disjoint S -paths in G. The r - path-connectivity π r (G) is defined as π r (G) = min { π G (S) | S ⊆ V (G) , | S | = r } , where 2 ≤ r ≤ | V (G) |. In this paper, we focus on the 3-path-connectivity of the n -dimensional star graph S n and obtain that π 3 (S n) = 3 (n − 1) − 1 4 with n ≥ 3. [ABSTRACT FROM AUTHOR]

We study the problem of fairly allocating a divisible resource in the form of a graph, also known as graphical cake cutting. Unlike for the canonical interval cake, a connected envy-free allocation is not guaranteed to exist for a graphical cake. We focus on the existence and computation of connected allocations with low envy. For general graphs, we show that there is always a 1 / 2 -additive-envy-free allocation and, if the agents' valuations are identical, a (2 + ϵ) -multiplicative-envy-free allocation for any ϵ > 0. In the case of star graphs, we obtain a multiplicative factor of 3 + ϵ for arbitrary valuations and 2 for identical valuations. We also derive guarantees when each agent can receive more than one connected piece. All of our results come with efficient algorithms for computing the respective allocations. [ABSTRACT FROM AUTHOR]

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The connectivity is one of the crucial parameters of network used to transport network flow, routing problems and bandwidth allocation problems. The increased connectivity makes a network more stable. In this paper, a new parameter called connectivity status of a vertex is introduced in the intuitionistic fuzzy graph. The related definitions and propositions of connectivity status of a vertex are proposed and investigated in an intuitionistic fuzzy graph. Specifically, connectivity status and status sequence are defined and analysed with various examples. After deleting a vertex, we classify the vertices of an intuitionistic fuzzy graph as connectivity status enhancing vertices, connectivity status neutral vertices and connectivity status reducing vertices because of the change of connectivity status. Finally, we establish two algorithms for these concepts and give an application to illustrate feasibility of algorithms. [ABSTRACT FROM AUTHOR]

Young people struggle with permanent online connection that is associated with their generation. This article looks at teenagers' affective relationship to connectivity and disconnectivity, and how it is socioculturally influenced by the media, family, and peers. It reports on an interview study with 36 teenagers between 15 and 19 years of age from Norway and Portugal. Our findings evidenced how disconnection may arise out of a latent feeling of "disaffect" generated in the experience of the ambience of connected and platform culture as well as the media; or of the unavailability created by how teenagers spend their leisure time, which is influenced by families' moral economies. Teenagers have to perform affective labor in managing the different, sometimes contradictory, forces that converge in the experience of connectivity. Managing digital disconnection appears as an individual—but socially produced—moral obligation to self-govern, to which teenagers have unequal conditions. [ABSTRACT FROM AUTHOR]

Memory impairment is one of the main characteristics of postoperative cognitive dysfunction. It remains elusive how postoperative pathological changes of the brain link to the memory impairment. The clinical setting of perioperation was mimicked via partial hepatectomy under sevoflurane anaesthesia together with preoperative restraint stress (Hep‐Sev‐stress) in mice. Memory changes were assessed with fear conditioning. The medial prefrontal cortex (mPFC)‐dorsal hippocampus connectivity was evaluated with injecting neurotracer 28 days before surgery. Astrocytic activation was limited via injecting AAV‐GFAP‐hM4Di‐eGFP into the mPFC. Astrocytic and microglial phagocytosis of synapses were visualised with co‐labelling hippocampal neuronal axon terminals with PSD‐95 and S100β or Iba1. Neuroinflammation and oxidative stress status were also detected. Hep‐Sev‐stress impaired the memory consolidation (mean [standard error], 49.91 [2.55]% vs. 35.40 [3.97]% in the contextual memory, p = 0.007; 40.72 [2.78]% vs. 27.77 [2.22]% in cued memory, p = 0.002) and the cued memory retrieval (39.00 [3.08]% vs. 24.11 [2.06]%, p = 0.001) in mice when compared with these in the naïve controls. Hep‐Sev‐stress damaged the connectivity from the dorsal hippocampus to mPFC but not from the mPFC to the dorsal hippocampus and increased the astrocytic but not microglial phagocytosis of hippocampal neuronal axon terminals in the mPFC. The intervention also induced neuroinflammation and oxidative stress in the dorsal hippocampus and the mPFC in a regional‐dependent manner. Limiting astrocyte activation in the mPFC alleviated memory consolidation impairment induced by Hep‐Sev‐stress. Postoperative memory consolidation was impaired due to astrocytic phagocytosis‐induced connectivity injury from the dorsal hippocampus to the medial prefrontal cortex. [ABSTRACT FROM AUTHOR]

Non-human primates are extensively used in neuroscience research as models of the human brain, with the rhesus macaque being a prominent example. We have previously introduced a set of tractography protocols (XTRACT) for reconstructing 42 corresponding white matter (WM) bundles in the human and the macaque brain and have shown cross-species comparisons using such bundles as WM landmarks. Our original XTRACT protocols were developed using the F99 macaque brain template. However, additional macaque template brains are becoming increasingly common. Here, we generalise the XTRACT tractography protocol definitions across five macaque brain templates, including the F99, D99, INIA, Yerkes and NMT. We demonstrate equivalence of such protocols in two ways: (a) Firstly by comparing the bodies of the tracts derived using protocols defined across the different templates considered, (b) Secondly by comparing the projection patterns of the reconstructed tracts across the different templates in two cross-species (human–macaque) comparison tasks. The results confirm similarity of all predictions regardless of the macaque brain template used, providing direct evidence for the generalisability of these tractography protocols across the five considered templates. [ABSTRACT FROM AUTHOR]

The settlement of Poliochni, located on the east coast of Lemnos Island (northeast Aegean), stands out as one of the largest early urban centres in the Early Bronze Age Aegean. It is often referred to as the “oldest city in Europe” due to its remarkable urban planning and richness of material culture. Excavations at Poliochni have brought to light important evidence that testify to its nodal position and receptiveness to cultural interactions across the Aegean and beyond, including an array of craft innovations and acts of communal control. Traditionally viewed as a maritime-oriented community with strong Trojan influences and extensive connections with the Cyclades and Mainland Greece, as indicated by distinctive pottery styles and imported raw materials and artefacts, Poliochni’s ceramic assemblage presents a diverse array that incorporates elements from both the Aegean and western Anatolia. This paper offers an analytical overview of the pottery excavated by the Italian Archaeological School at Athens during the 1930s and 1950s. Thin-section petrography and elemental analysis with WD-XRF have allowed a first characterisation of the local potting traditions and a diachronic assessment of raw material exploitation strategies of southeast Lemnos. More importantly, this paper significantly contributes to our knowledge of exchange networks and connectivity during the third millennium BC, through the identification of imports with provenance locations on several islands in the central and northeast Aegean. [ABSTRACT FROM AUTHOR]

A graph G is (2 , m) -linked if, for any distinct vertices a 1 , ... , a m , b 1 , b 2 in G , there exist disjoint connected subgraphs A , B of G such that a 1 , ... , a m ∈ V (A) and b 1 , b 2 ∈ V (B). A fundamental result in structural graph theory is the characterization of (2 , 2) -linked graphs. It appears to be difficult to characterize (2 , m) -linked graphs for m ≥ 3. In this paper, we provide a partial characterization of (2 , m) -linked graphs. This implies that every (2 m + 2) -connected graphs G is (2 , m) -linked and for any distinct vertices a 1 , ... , a m , b 1 , b 2 of G , there is a path P in G between b 1 and b 2 and avoiding { a 1 , ... , a m } such that G − P is connected, improving a previous connectivity bound of 10 m. [ABSTRACT FROM AUTHOR]

Background: Research has increasingly recognized sex differences in aging and Alzheimer's Disease (AD) susceptibility. However, sex effects on the medial temporal lobe (MTL), a crucial region affected by aging and AD, remain poorly understood when it comes to the intricacies of morphology and functional connectivity. This study aimed to systematically analyze structural and functional connectivity among MTL subregions, which are known to exhibit documented morphological sex differences, during midlife, occurring before the putative pivotal age of cerebral decline. The study sought to explore the hypothesis that these differences in MTL subregion volumes would manifest in sex-related functional distinctions within the broader brain network. Methods: 201 cognitively unimpaired adults were included and stratified into four groups according to age and sex (i.e., Women and Men aged 40–50 and 50–60). These participants underwent comprehensive high-resolution structural MRI as well as resting-state functional MRI (rsfMRI). Utilizing established automated segmentation, we delineated MTL subregions and assessed morphological differences through an ANOVA. Subsequently, the CONN toolbox was employed for conducting ROI-to-ROI and Fractional Amplitude of Low-Frequency Fluctuations (fALFF) analyses to investigate functional connectivity within the specific MTL subregions among these distinct groups. Results: Significant differences in volumetric measurements were found primarily between women aged 40–50 and men of all ages, in the posterior hippocampus (pHPC) and the parahippocampal (PHC) cortex (p < 0.001), and, to a lesser extent, between women aged 50–60 and men of all ages (p < 0.05). Other distinctions were observed, but no significant differences in connectivity patterns or fALFF scores were detected between these groups. Discussion: Despite notable sex-related morphological differences in the posterior HPC and PHC regions, women and men appear to share a common pattern of brain connectivity at midlife. Longitudinal analyses are necessary to assess if midlife morphological sex differences in the MTL produce functional changes over time and thus, their potential role in cerebral decline. Clinical trial number: Not applicable. [ABSTRACT FROM AUTHOR]

Indigenous stewardship is essential to the conservation of biocultural diversity, yet conventional conservation models often treat Indigenous territories (ITs) as homogeneous or isolated units. We propose that archipelagos of Indigenous territories (AITs), clusters of ITs that span geographies but are connected through shared cultural or political ties maintained by Indigenous nations, are crucial for understanding and enhancing conservation strategies that recognize the complexity of Indigenous stewardship. We classified 3572 ITs in the Amazon into 4 categories—single or multiple nations with either singular IT or AIT—to assess their spatial heterogeneity, governance, and conservation potential. We then assessed species richness, carbon stocks, and pressures across these different categories. To examine how AITs can enhance biocultural conservation efforts, we conducted a case study of the Cofán Nation in Ecuador. AITs covered 45% of the Amazonian land area and had higher species richness and carbon stocks than single IT configurations. However, AITs faced greater pressures from development and extractive activities. In the case study, the Cofán AIT was shaped by colonization and land titling challenges, but their community‐driven governance, cross‐territorial collaboration, and adaptive responses—such as comanagement agreements and resisting extractive activities—enhanced their ecological and cultural resilience amid growing development pressures. Our findings suggest that AITs facilitate the exchange of resources, knowledge, and cultural practices, which strengthens social connectivity, reinforces governance structures, and enables adaptive management across ITs, thereby enhancing biocultural resilience across discontinuous spaces. This work advocates for a paradigm shift in conservation planning and practice that recognizes the vital role of AITs in sustaining Amazonian ecosystems and Indigenous lifeways, particularly in the face of increasing pressures. [ABSTRACT FROM AUTHOR]

The development of fetal organs can be impacted by systemic changes in maternal circulation, with the placenta playing a pivotal role in maintaining pregnancy homeostasis and nutrient exchange. In clinical obstetrics, oxytocin (OXT) is commonly used to induce labor. To explore the potential role of OXT in the placental homeostasis of OXT, we compared OXT levels in neonatal cord blood among neonates (23–42 weeks gestation) whose mothers either received prenatal OXT or experienced spontaneous labor. Our previous research revealed that the oxytocin receptor (OXTR), essential in forming the blood–retina barrier, is expressed in the retinal pigment epithelium (RPE). We hypothesized that perinatal OXT administration might influence the development of the neural retina and its vasculature, offering therapeutic potential for retinal diseases such as retinopathy of prematurity (ROP). Plasma OXT levels were measured using a commercial OXT ELISA kit. Human fetal RPE (hfRPE) cells treated with OXT (10 µM) were assessed for gene expression via RNA sequencing, revealing 14 downregulated and 32 upregulated genes. To validate these differentially expressed genes (DEGs), hfRPE cells were exposed to OXT (0.01, 0.1, 1, or 10 µM) for 12 h, followed by RNA analysis via real-time PCR. Functional, enrichment, and network analyses (Gene Ontology term, FunRich, Cytoscape) were performed to predict the affected pathways. This translational study suggests that OXT likely crosses the placenta, altering fetal OXT concentrations. RNA sequencing identified 46 DEGs involved in vital metabolic and signaling pathways and critical cellular components. Our results indicate that the perinatal administration of OXT may affect neural retina and retinal vessel development, making OXT a potential therapeutic option for developmental eye diseases, including ROP. [ABSTRACT FROM AUTHOR]

During paradoxical sleep (PS, aka REM sleep) the cerebral cortex displays rapid electroencephalographic activity similar to that of wakefulness, whereas in the posterior associative thalamus, rapid activity is interrupted by frequent periods of slow‐wave (delta) oscillations at 2–3 Hz, thereby dissociating the intrinsic frequency in thalamus and cortex. Here we studied the functional consequences of such a dissociation using intrathalamic and intracortical recordings in 21 epileptic patients, applying coherence analysis to examine changes in functional connectivity between the posterior thalamus (mainly medial pulvinar) and six cortical functional networks, and also between each cortical network with respect to the others. Periods of slow‐wave thalamic activity ('delta PS') were more prevalent than phases of 'rapid PS,' and the delta/rapid thalamic alternance did not overlap with the classical tonic/phasic dichotomy based on rapid eye movements. Thalamo‐cortical and cortico‐cortical functional connectivity significantly decreased during delta PS, relative to both rapid PS periods and to wakefulness. The fact that delta thalamic activity and low thalamo‐cortical binding coincided with a suppression of cortico‐cortical connectivity supports a crucial role for the posterior associative thalamus, and particularly the medial pulvinar, in ensuring trans‐thalamic communication between distant cortical areas. Disruption of such a trans‐thalamic communication during delta PS compromises the functional binding between cortical areas, and consequently might contribute to the alteration of perceptual experiences commonly reported during dreams. Key points: During paradoxical, or REM, sleep (PS), rapid thalamic activity is interrupted by frequent periods of slow delta waves at 2–3 Hz.During these periods of thalamic delta activity there was a drastic drop of functional connectivity between associative thalamus and cortex, and also among different cortical networks.The delta/rapid alternance did not overlap with the classically defined 'tonic/phasic' periods and therefore suggests a distinct dichotomy of functional states in PS.Recurrent decrease in thalamo‐cortical and cortico‐cortical functional connectivity during PS may compromise the spatio‐temporal binding between cortical areas, which in turn could hinder the formation of coherent mental content during dreams. [ABSTRACT FROM AUTHOR]

Summary: Understanding the drivers of assemblages of arbuscular mycorrhizal fungi (AMF) is essential to leverage the benefits of AMF for plant growth and health. Arbuscular mycorrhizal fungi are heterogeneously distributed in space even at small scale. We review the role of plant distribution in driving AMF assemblages (the passenger hypothesis), using a transposition of the conceptual framework of landscape ecology. Because rooting systems correspond to habitat patches with limited carrying capacity that differ in quality due to host‐preference effects, we suggest considering plant communities as mosaics of AMF microhabitats. We review how predictions from landscape ecology apply to plant community effects on AMF, and the existing evidence that tests these predictions. Although many studies have been conducted on the effect of plant compositional heterogeneity on AMF assemblages, they mostly focused on the effect of plant richness, while only a few investigated the effect of configurational heterogeneity, plant connectivity or plant community temporal dynamics. We propose key predictions and future prospects to fill these gaps. Considering plant communities as landscapes extends the passenger hypothesis by including a spatially explicit dimension and its associated ecological processes and may help understand and manipulate AMF assemblages at small spatial scales. [ABSTRACT FROM AUTHOR]

Mass transport in frozen ground is typically regarded slow. However, a highly permeable path can exist in frozen saline sand if the unfrozen water is interconnected at the pore scale. We therefore should consider when the unfrozen water is connected and how permeable can frozen saline sand be, yet there are few studies. This research utilizes in‐situ X‐ray CT to evaluate unfrozen water connectivity and permeability in frozen saline sand considering effects of initial salt content, temperature, freezing rate, and temperature gradient. Results show that higher initial salt content and/or temperature, both of which results in a higher unfrozen water content, easily maintains unfrozen water connectivity. Rapid freezing minimizes the brine expulsion and permits a higher unfrozen water content hence better connectivity. Permeability in frozen saline sand can be several orders higher than the typically reported value, highlighting the potential presence of rapid mass transport through the connected unfrozen water. Plain Language Summary: Frozen aqueous sandy soils in nature often contain a lot of substances such as dissolved salts, gases, contaminants. Mass migration via unfrozen water is of vital importance to groundwater flow, greenhouse gas emission, even contaminated soil remediation. Permeability determination of unfrozen water is well‐studied in salt‐free soils. Our study shows there can be a highly conductive path in frozen saline sand when the unfrozen water is interconnected, even at a low unfrozen water saturation of 14%. The connectivity of unfrozen water remains at −20°C with an initial salt concentration similar to seawater. Rapid freezing causes better connectivity because less unfrozen water is squeezed out of the frozen sand during ice growth. Permeability in frozen saline sand can be several orders of magnitude higher than the typically reported value. These findings indicate that mass transport in frozen ground, via the connected unfrozen water, can be much more active than previously thought. Key Points: Pore‐scale unfrozen water can be interconnected, enabling fast mass transport below 0°C when soil contains saltRapid freezing enhances unfrozen water connectivity and permeability due to less and slower salt migration during freezingPermeability of frozen saline sand can be several orders of magnitude higher than that of salt‐free soil [ABSTRACT FROM AUTHOR]

Let G be a connected graph and S ⊆ V (G) with | S | ≥ 2. A tree T in G is called an S -tree if S ⊆ V (T). Two S -trees T 1 and T 2 are internally disjoint if E (T 1) ∩ E (T 2) = 0̸ and V (T 1) ∩ V (T 2) = S. For an integer k ≥ 2 , the generalized k -connectivity of a graph G , denoted by κ k (G) , is defined as κ k (G) = min { κ G (S) : S ⊆ V (G) and | S | = k } , where κ G (S) denotes the maximum number of pairwise internally disjoint S -trees in G. The generalized connectivity is a generalization of traditional connectivity. Let G n be the class of connected graphs of order n and let f (n , k , t) = min G ∈ G n { | E (G) | : κ k (G) = t }. In this paper, we prove f (n , k , t) ≥ ⌈ t (t + 2) 2 t + 2 n ⌉ for 4 ≤ k ≤ n and 1 ≤ t ≤ n − ⌈ k 2 ⌉. In particular, the lower bound is sharp when k = 4 and t = 2 (i.e., we explicitly provide a family of graphs fulfilling the bound in this case), improving the known results of Sun et al. (2021). [ABSTRACT FROM AUTHOR]

The existing literature provides limited insights into the dynamics of phytoplankton communities and the spatial heterogeneity of physicochemical parameters in multisystem cascade reservoirs (interconnected reservoirs derived from different rivers). The existing studies are concentrated on cascade reservoirs (interconnected reservoirs derived from the same river). To address this knowledge gap, the aims of the present study were as follows: (1) investigate the spatial heterogeneity, within and between reservoirs, of geochemical parameters associated with the eutrophication process, considering total phosphorus, chlorophyll-a, pheophytin, and metals (chromium, copper, nickel, lead, zinc, iron, and manganese); (2) evaluate sediment quality at the designated locations; (3) assess differences in the richness and concentration of sedimentary photopigments between the reservoirs. Application of principal component analysis revealed discernible gradients for the abiotic variables, although the differences were not statistically significant (one-way PERMANOVA test, p > 0.05). The observations suggested a tendency towards spatial homogeneity within and between the reservoirs. The metal concentrations were consistent with regional reference values, while phosphorus levels in the sediment approached the threshold for classification as pollution (~ 2000 mg/kg). Analysis of pigments indicated low dissimilarity among the reservoirs, which could be mainly attributed to the eutrophication process and high connectivity of the sampled areas. To counteract ongoing biotic homogenization, it is essential to reduce nutrient inputs and invest in ecological protection and restoration programs. The analysis of sedimentary photopigments provides an efficient and cost-effective alternative way to assess phytoplankton communities. [ABSTRACT FROM AUTHOR]

Advection of pelagic fish larvae through ocean currents is a source of dispersal that is known to structure marine populations by directly impacting population success and persistence. To be able to understand fish population dynamics and manage existing fisheries it is therefore of importance to assess the extent of exchange between populations and determine the factors that drive it, which is still a challenge in fisheries research today. In this study, the output of a high-resolution basin-scale circulation model is used to calculate the dispersal probability from spawning areas and the remaining Black Sea for a range of commercially important fish such as anchovy, sprat, turbot, red mullet, and bluefish under different environmental conditions. The common trait of many commercially important species in the Black Sea is that they have pelagic larval stages of different time scales which are simulated by tracking virtual drifters in the simulated surface circulation of the Black Sea. Simulation results show that the dynamic current structure of the Black Sea causes low local retention of larvae. During spring and summer lower offshore transport and higher local retention is observed than in fall and winter, which is directly related to the Rim Current strength. The lowest offshore transport is observed on the northern northwestern shelf, the main spawning area for pelagic fish with still 24-32% of larvae transported offshore. Simulations show that pelagic fish species such as anchovy and sprat adopted different reproductive strategies through their species-specific traits. For the summer spawning species anchovy, timing, and location of spawning together with its short pelagic larval stage is shown to enhance retention on the northwestern shelf. Sprat with its long pelagic larval stage and winter spawning is more adapted to high offshore transport, making it unlikely that sprat is recruited to the same area as where it is spawned. This modeling framework provides a basis for investigating recruitment variability of pelagic fish species in the Black Sea specifically considering the impact of climate variability and provides a useful guide to the potential connectivity of marine populations or the spread of invasive pests in the Black Sea. [ABSTRACT FROM AUTHOR]

The ability to modulate specific neural circuits and simultaneously visualize and measure brain activity with MRI would greatly impact our understanding of brain function in health and disease. The combination of neurostimulation methods and functional MRI in animal models have already shown promise in elucidating fundamental mechanisms associated with brain activity. We developed an innovativemagnetogenetics neurostimulation technology that can trigger neural activity through magnetic fields. Similar to other genetic-based neuromodulation methods, magnetogenetics offers cell-, area-, and temporal- specific control of neural activity. Themagnetogenetic protein--Electromagnetic Perceptive Gene (EPG)--is activated by non-invasive magnetic fields, providing a unique way to target neural circuits by the MRI static and gradient fields while simultaneously measuring their effect on brain activity. EPG was expressed in rat's visual cortex and the amplitude of low-frequency fluctuation, resting-state functional connectivity (FC), and sensory activation was measured using a 7T MRI. The results demonstrate that EPG-expressing rats had significantly higher signal fluctuations in the visual areas and stronger FC in sensory areas consistent with known anatomical visuosensory and visuomotor connections. This new technology complements the existing neurostimulation toolbox and provides a means to study brain function in a minimally-invasive way which was not possible previously. [ABSTRACT FROM AUTHOR]

Protected areas are a primary instrument for biodiversity conservation, and area-based targets have become a hallmark of global efforts with the 2022 Kunming-Montreal Global Biological Framework recommending at least 30 percent of land and water be protected by 2030. In parallel, the United States has implemented “America the Beautiful,” a call for local, state, and regionally led efforts to conserve, connect, and restore 30 percent of U.S. lands and waters by 2030. Achieving these goals is complicated, however, by the multiple policy scales at which conservation decisions are made and governed and the limited guidance provided on how gains to protected and connected areas should be evaluated. We assess the connectedness of U.S. protected areas at multiple scales and find that less than 3 percent of the United States is protected and connected. Connectedness increases when the area under investigation is partitioned into smaller policy units (e.g., counties), a product of the modifiable areal unit problem. Similarly, connectedness values increase by an order of magnitude when assessed relative to the protected area network rather than considering all land area. Both findings support the need for standardized reporting frameworks and highlight the challenges in coordinating conservation goals across administrative units. [ABSTRACT FROM AUTHOR]

For patients with refractory epilepsy, the seizure onset zone (SOZ) plays an essential role in determining the specific regions of the brain that will be surgically resected. High-frequency oscillations (HFOs) and connectivity-based approaches have been identified among the potential biomarkers to localize the SOZ. However, there is no consensus on how connectivity between HFO events should be estimated, nor on its subject-specific short-term reliability. Therefore, we propose the channel-level connectivity dispersion (CLCD) as a metric to quantify the variability in synchronization between individual electrodes and to identify clusters of electrodes with abnormal synchronization, which we hypothesize to be associated with the SOZ. In addition, we developed a specialized filtering method that reduces oscillatory components caused by filtering broadband artifacts, such as sharp transients, spikes, or direct current shifts. Our connectivity estimates are therefore robust to the presence of these waveforms. To calculate our metric, we start by creating binary signals indicating the presence of high-frequency bursts in each channel, from which we calculate the pairwise connectivity between channels. Then, the CLCD is calculated by combining the connectivity matrices and measuring the variability in each electrode's combined connectivity values. We test our method using two independent open-access datasets comprising intracranial electroencephalography signals from 89 to 15 patients with refractory epilepsy, respectively. Recordings in these datasets were sampled at approximately 1000 Hz, and our proposed CLCDs were estimated in the ripple band (80-200 Hz). Across all patients in the first dataset, the average ROC-AUC was 0.73, and the average Cohen's d was 1.05, while in the second dataset, the average ROC-AUC was 0.78 and Cohen's d was 1.07. On average, SOZ channels had lower CLCD values than non-SOZ channels. Furthermore, based on the second dataset, which includes surgical outcomes (Engel I-IV), our analysis suggested that higher CLCD interquartile (as a measure of CLCD distribution spread) is associated with favorable outcomes (Engel I). This suggests that CLCD could significantly assist in identifying SOZ clusters and, therefore, provide an additional tool in surgical planning for epilepsy patients. [ABSTRACT FROM AUTHOR]

Enhancing habitat connectivity is a key strategy for conserving endangered species in anthropogenic landscapes. However, connectivity planning often overlooks the crucial energetic costs to animals of traversing complex terrains. We applied a novel approach for estimating energy costs of movement for tigers – a globally endangered species. We used those estimates to calculate landscape connectivity for these animals across the extreme altitudinal gradient of Nepal, where recent sightings of tigers at higher elevations (~3200 m) suggest an upward range expansion from the tiger‐rich lowlands. To evaluate our estimates, we simulated tiger routes to higher‐elevation locations and compared modeled energy costs of those ascents to those derived from a previous model calibrated with data from GPS‐collared tigers in Russia. In areas below 3200 m, we found about 7.5 times greater land areas with high connectivity outside protected areas (~51 000 km2) than inside (~6800 km2). However, most of the highly connected areas below 3200 m consist of croplands (56%). Importantly, community‐managed forests, which spanned the altitudinal gradient, tended to include areas with moderate levels of connectivity. Our estimates of energy costs and those from Russia showed a strong consensus (ρ = 0.70, P < 0.05), with ours better capturing the higher energy costs of traversing mountains and of very large total ascents. Our results show that while barriers to tiger movement across Nepal are ubiquitous, other effective area‐based conservation measures (OECMs), like community‐managed forests, can play prominent roles in promoting tiger habitat connectivity while minimizing human–tiger conflict across anthropogenic landscapes. Our results also underscore the utility of integrating first principles of energy efficiency into connectivity analyses and planning. [ABSTRACT FROM AUTHOR]

Characterizing the genetic diversity of a species is crucial for understanding the factors that influence its local dispersion and population dynamics. Additionally, it provides insights into local processes that may affect the distribution of other species. Lineus sanguineus (Rathke, 1799) is a widely distributed species commonly found on fouling fauna along rocky shores. This species can reproduce asexually by fissiparity, and its pilidium larva facilitates dispersal, similar to other heteronemerteans. The present study utilized a population genetics approach combined with Ecological Niche Modeling analysis to evaluate L. sanguineus populations along the Brazilian coast. We used sequences from two mtDNA regions, 16S ribosomal RNA (16SrRNA) and cytochrome c oxidase subunit 1 (COI), and one nuclear region, Internal Transcribed Spacer 1 (ITS-1), from 85 specimens sampled in nine locations. Genetic diversity analysis revealed greater genetic variation for the ITS-1 marker compared to mtDNA, as evidenced by higher intrapopulation diversity values. There was no clear geographic pattern, and the AMOVA analysis revealed low to moderate genetic structuring and high connectivity among sampled localities, with most of the genetic variation contained within populations. The pairwise FST results indicate high genetic structuring between the Northeast and localities along the South and Southeast of Atlantic coastlines. This pattern suggests that Brazilian oceanic currents play an important role in species connectivity. The paleodistribution pattern demonstrated that the colonization could have occured from the South to the Northeast of the continent. These results reinforce that sexual reproduction and larval dispersion play a vital role in the connectivity of these Southwest Atlantic populations and that oceanographic currents, rafting and artificial transport facilitate these processes. [ABSTRACT FROM AUTHOR]

Mesozooplankton is a key component of the ocean, regulating global processes such as the carbon pump, and ensuring energy transfer from lower to higher trophic levels. Yet, knowledge on mesozooplankton diversity, distribution and connectivity at global scale is still fragmented. To fill this gap, we applied DNA metabarcoding to mesozooplankton samples collected during the Malaspina‐2010 circumnavigation expedition across the Atlantic, Indian and Pacific oceans from the surface to bathypelagic depths. We highlight the still scarce knowledge on global mesozooplankton diversity and identify the Indian Ocean and the deep sea as the oceanic regions with the highest proportion of hidden diversity. We report no consistent alpha‐diversity patterns for mesozooplankton at a global scale, neither across vertical nor horizontal gradients. However, beta‐diversity analysis suggests horizontal and vertical structuring of mesozooplankton communities mostly attributed to turnover and reveals an increase in mesozooplankton beta‐diversity with depth, indicating reduced connectivity at deeper layers. Additionally, we identify a water mass type‐mediated structuring of mesozooplankton bathypelagic communities instead of an oceanic basin‐mediated as observed at upper layers. This suggests limited dispersal at deep ocean layers, most likely due to weaker currents and lower mixing of water mass types, thus reinforcing the importance of oceanic currents and barriers to dispersal in shaping global plankton communities. [ABSTRACT FROM AUTHOR]

Despite substantial neuroscience research in the last decade revealing the claustrum's prominent role in mammalian forebrain organization, as evidenced by its extraordinarily widespread connectivity pattern, claustrum studies in humans are rare. This is particularly true for studies focusing on claustrum connections. Two primary reasons may account for this situation: First, the intricate anatomy of the human claustrum located between the external and extreme capsule hinders straightforward and reliable structural delineation. In addition, the few studies that used diffusion‐weighted‐imaging (DWI)‐based tractography could not clarify whether in vivo tractography consistently and reliably identifies claustrum connections in humans across different subjects, cohorts, imaging methods, and connectivity metrics. To address these issues, we combined a recently developed deep‐learning‐based claustrum segmentation tool with DWI‐based tractography in two large adult cohorts: 81 healthy young adults from the human connectome project and 81 further healthy young participants from the Bavarian longitudinal study. Tracts between the claustrum and 13 cortical and 9 subcortical regions were reconstructed in each subject using probabilistic tractography. Probabilistic group average maps and different connectivity metrics were generated to assess the claustrum's connectivity profile as well as consistency and replicability of tractography. We found, across individuals, cohorts, DWI‐protocols, and measures, consistent and replicable cortical and subcortical ipsi‐ and contralateral claustrum connections. This result demonstrates robust in vivo tractography of claustrum connections in humans, providing a base for further examinations of claustrum connectivity in health and disease. [ABSTRACT FROM AUTHOR]

Winter flounder Pseudopleuronectes americanus (Walbaum 1792) are a coastal flatfish species of economic and cultural importance that have dwindled to <15, % of their historic abundance in the southern New England/Mid‐Atlantic region of the United States, with evidence indicating near‐extirpation of certain local populations. This species exhibits intricate behaviors in spawning and migration that contribute to population complexity and resilience. These behaviors encompass full or partial philopatry to natal estuaries, the generation of multiple pulses of larval delivery, and partial migration. The patterns of genetic diversity within and among estuaries and cohorts presented here carry important implications in understanding the susceptibility to demographic shocks, even if the full extent of genetic diversity within and among winter flounder stocks on the US East Coast remains unresolved. Our findings reveal connectivity between estuaries in Long Island, New York, suggesting the potential for genetic rescue of depleted subpopulations. Family reconstruction and relatedness analysis indicate that split cohorts and migration contingents are not the result of genetically distinct lineages. We found no evidence for genetic structure separating these groups, and in some instances, we were able to detect closely related individuals that belonged to different migratory contingents or cohorts. Characterizing the spatial and behavioral organization of this species at the population level is crucial for comprehending its potential for recovery, not only in terms of biomass but also in reinstating the complex population structure that supports resilience. The search for generality in winter flounder spawning and migration behavior remains elusive, but perhaps the lack of generalities within this species is what has allowed it to persist in the face of decades of environmental and anthropogenic stressors. [ABSTRACT FROM AUTHOR]

Aim: The persistence of large carnivore populations depends on their survival outside protected areas, where they often impact local livelihoods through livestock depredation. Understanding the impacts of human behaviour on large carnivores in shared landscapes is thus important but is often overlooked in habitat assessments or conservation planning. We employed an integrated approach that considers human behaviour and landscape structure metrics to assess the potential for human‐puma (Puma concolor) coexistence in the Chaco region, a global deforestation and defaunation hotspot. Location: Argentine Dry Chaco (~490,000 km2). Methods: We identified suitable puma habitat patches and movement areas using occupancy modelling and combined it with a spatial human‐puma conflict risk model based on interview data to identify 'safe' and 'unsafe' habitat patches. We then used resistance surfaces to identify 'safe' and 'unsafe' movement areas, as well as 'severed' movement areas where anthropogenic land conversion inhibits movement. Results: Safe puma habitat patches (i.e., suitable and safe) covered 29% of the region, whereas attractive sinks (i.e., suitable but risky) represented 12%. Movement areas corresponded to 60% of the region, while conflict risk and high landscape resistance undermined connectivity: unsafe and severed movement areas covered 10% and 11% of the region, respectively. Nearly 98% of safe habitat and movement areas occurred outside protected areas. Main Conclusions: We provide an integrated conceptual framework and spatial explicit template for a three‐pronged conservation strategy to (1) protect safe habitat and movement areas, (2) mitigate livestock depredation in attractive sinks and unsafe movement areas and (3) restore landscape in severed and matrix areas to improve ecological connectivity. This would allow pumas to maintain viable populations while reducing negative impacts on local people. More generally, we show how integrating habitat and conflict risk models can reveal opportunities and challenges for human‐carnivore coexistence beyond protected areas. [ABSTRACT FROM AUTHOR]

Human‐transformed residuals, especially those derived from human waste (dumps), farmland, and livestock are involved in the emergence of antibiotic‐resistant bacteria (ARB) in the environment. Wildlife can act as vectors of ARB dispersal through different environments, but also as sentinels to detect the early spread and determine ARB sources. The development of integrated monitoring programmes focused on wildlife would help to anticipate the risks of ARB to humans and livestock. We used the yellow‐legged gull (Larus michahellis) as a model species to investigate and monitor the spatial patterns of ARB dispersal across an extensive farmland region located in northeastern Spain (Lleida). By integrating GPS tracking data and ARB clinical testing for 26 individuals within a network analysis framework, we modelled the risk of spatial pathogen spread through faeces during the bacteria‐transmission latency period (16 days after sample collection). Additionally, we created a connectivity network to determine the main sources of ARB in the area, focusing on three main habitats of special risk for infection: dumps, livestock facilities, and irrigation ponds. Seven individuals were infected by Escherichia coli, with one also co‐infected with Listeria monocytogenes and Salmonella spp. Potential pathogen dispersal distances ranged from 1.13 km to 23.13 km from the breeding colony. Our network analyses revealed 54 main nodes (i.e. high‐risk habitats recurrently visited by tracked gulls) and 1182 links among them. Our findings revealed a high degree of connectivity between the breeding area, located in a shallow lake, and nearby dumps, highlighting them as significant contributors to ARB dispersal. Synthesis and applications: The integration of GPS data, pathogen testing and network analyses can shed further light on pathogen dynamics by creating spatial risk maps and identifying ARB sources. In combination with complementary molecular epidemiology techniques within a One Health framework, our approach can emerge as an important tool for monitoring ARB dynamics within highly human‐transformed ecosystems. This may empower managers for the development of targeted ARB monitoring programmes and effective mitigation strategies, ultimately improving both animal and public health. [ABSTRACT FROM AUTHOR]

The common opossum (Didelphis marsupialis) is a marsupial widely distributed in the Neotropics, where it lives in urbanized environments. The apparent scarcity and fragmentation of available habitat, and high rates of vehicle collisions, may represent barriers to dispersal. To assess the functional connectivity of this species and its potential use as a model in urban ecology, we evaluated the structure and genetic diversity of opossums in the metropolitan area of the Aburrá Valley (AMVA), Colombia, using sequences of the mitochondrial Cytochrome B (Cytb) gene and nine autosomal microsatellite loci. Although Cytb presented low levels of variation, microsatellite markers revealed high genetic diversity (He = 0.852 and Ho = 0.698). The geographic distribution of mitochondrial lineages and a spatial principal component analysis (sPCA) of microsatellites showed the absence of genetic structure and effective barriers to dispersal of opossums in the study area. This scenario suggests that hostile landscapes such as those in urban environments may be suitable enough to allow the effective connectivity of some species such as the common opossum and others with high dispersal ability in urbanized areas. Nonetheless, it is necessary to evaluate the impact of releases of rescued fauna made by the environmental authority on the population structure of urban opossums. [ABSTRACT FROM AUTHOR]

Fluvial networks are characterised by spatial and temporal transitions as geomorphic and ecological processes within these systems are mediated longitudinally by sediment and water fluxes which vary spatially in magnitude and variability. The aim of this special issue was to shed light on the nature of source-to-sink fluvial transitions associated with spatial and temporal variability in geomorphic and hydrological processes. We encouraged contributions that considered fluvial transitions at any spatial or temporal scale, and invited research that addressed the implications of such transitions. The number of submissions was limited, which was potentially indicative of the lack of field-based studies being conducted at a catchment- or source-to-sink scale. Two of the published submissions considered longitudinal transitions in sediment sources using a sediment finger-printing approach, while the remaining two articles combined traditional fluvial sedimentology techniques with optically stimulated luminescence chronology to deduce controls on river reach flood dynamics. As we enter a time of unprecedented human impact on the environment, there is a clear need for future research to focus on the catchment as a holistic unit as the interconnectedness of landscape pattern and process has implications for biodiversity, water quality, ecosystem service provision and thus catchment management. [ABSTRACT FROM AUTHOR]

Cognitive models state that social anxiety (SA) involves biased cognitive processing that impacts what is learned and remembered within social situations, leading to the maintenance of SA. Neuroscience work links SA to enhanced error monitoring, reflected in error-related neural responses arising from mediofrontal cortex (MFC). Yet, the role of error monitoring in SA remains unclear, as it is unknown whether error monitoring can drive changes in memory, biasing what is learned or remembered about social situations. Motivated by the longer-term goal of identifying mechanisms implicated in SA, in the current study we developed and validated a novel paradigm for probing the role of error-related MFC theta oscillations (associated with error monitoring) and incidental memory biases in SA. Electroencephalography (EEG) data were collected while participants completed a novel Face-Flanker task, involving presentation of task-unrelated, trial-unique faces behind target/flanker arrows on each trial. A subsequent incidental memory assessment evaluated memory biases for error events. Severity of SA symptoms were associated with greater error-related theta synchrony over MFC, as well as between MFC and sensory cortex. Social anxiety also was positively associated with incidental memory biases for error events. Moreover, greater error-related MFC-sensory theta synchrony during the Face-Flanker predicted subsequent incidental memory biases for error events. Collectively, the results demonstrate the potential of a novel paradigm to elucidate mechanisms underlying relations between error monitoring and SA. [ABSTRACT FROM AUTHOR]

Protected areas play a crucial role in current global policies to mitigate the erosion of biodiversity and systematic reserve site selection models are increasingly involved in their design. These models address the optimisation problem that seeks to cover spaces hosting biodiversity features with nature reserves at a minimum cost for human activities. To increase the likelihood of a successful implementation, reserves need to be spatially consistent. Widely used decision support tools such as Marxan and PrioritizR commonly enforce compactness indirectly by penalising the reserve perimeter in the objective function. Few other optimisation models explicitly consider spatial properties such as limited fragmentation, connectivity of selected sites, and buffer zones around them, etc. So far, no reserve site selection model can guarantee the production of a connected, compact, and gap-free reserve all at once. The impossibility of designing reserve solutions with desirable spatial properties using existing models makes it difficult to implement such solutions in the real world. Therefore, we propose a mixed-integer linear program to build a reserve that is connected, compact, and gap-free. To enforce these spatial attributes within a reserve site selection model, we used a multicommodity flow approach. We tested the computational feasibility of our model on generated instances and the real instance of Fernando de Noronha. The results indicate that a single model can be used to enforce compactness, connectivity, and the absence of gaps. Using this optimisation model, conservation practitioners can design reserve solutions with desirable spatial properties, thereby increasing the likelihood of a successful implementation. • We provide a mixed-integer linear program that allows the explicit designing of compact, connected and gap-free reserves. • These spatial characteristics are essential for the successful implementation of protected areas in the real world. • We propose several variations in the formulation to give greater control over the geometric characteristics of the reserves. • Compact, connected, and gap-free reserves do not result in a significant increase in socio-economic costs. • Our model can solve instances of 500 planning units within a realistic timeframe, although larger instances may be addressed. [ABSTRACT FROM AUTHOR]

To expand the scale of spiking neural networks (SNNs), an interface circuit that supports multiple SNN cores is essential. This circuit should be designed using an asynchronous approach to leverage characteristics of SNNs similar to those of the human brain. However, the absence of a global clock presents timing issues during implementation. Hence, we propose an intermediate latching template to establish asynchronous nonlinear connectivity with multipipeline processing between multiple SNN cores. We design arbitration and distribution blocks in the interface circuit based on the proposed template and fabricate an interface circuit that supports four SNN cores using a full‐custom approach in a 28‐nm CMOS (complementary metal–oxide–semiconductor) FDSOI (fully depleted silicon on insulator) process. The proposed template can enhance throughput in the interface circuit by up to 53% compared with the conventional asynchronous template. The interface circuit transmits spikes while consuming 1.7 and 3.7 pJ of power, supporting 606 and 59 Mevent/s in intrachip and interchip communications, respectively. [ABSTRACT FROM AUTHOR]

Saturated hydraulic conductivity (Ks) is a crucial parameter that influences water flow in saturated soils, with applications in various fields such as surface water runoff, soil erosion, drainage, and solute transport. However, accurate determination of Ks is challenging due to temporal and spatial uncertainties. This study addresses the knowledge gap regarding the long‐term behavior of Ks in sandy soils with less than 10% fine particles. The research investigates the changes in Ks over a long period of constant head tests and examines the factors influencing its variation. Two sandy samples were tested using a hydraulic conductivity cell, and the hydraulic head and discharge were recorded for over 50 days. The results show a general decline in Ks throughout the test, except for brief periods of increase. At the end of both tests, there are noticeable reductions in the saturated hydraulic conductivities of the samples, with one sample being 96% and the other sample 91% less than the maximum recorded saturated hydraulic conductivity during the tests. Furthermore, the relationship between flow rate and hydraulic head gradient does not follow the expected linear correlation from Darcy's law, highlighting the complex nature of sandy soil saturated hydraulic conductivity. The investigation of soil properties in three different sections of the samples before and after the tests revealed a decrease in the percentage of fine particles and a shift in specific gravity from the bottom to the top of the sample, suggesting particle migration along the flow direction. Factors such as clogging by fine particles and pore pressure variation contribute to the changes in Ks. The findings of this research show the importance of considering changes of saturated hydraulic conductivity during constant‐head laboratory tests. Therefore, this study provides evidence for the requirement to further assess the laboratory methods for measurement of the saturated hydraulic conductivity in sandy soil mixtures. Key Points: The estimation of saturated hydraulic conductivity through constant head tests demonstrates sensitivity to the duration of the testsObservations indicate an alteration in particle size distribution before and after testing within different sections of the samplesFlow rate and hydraulic gradient vary over the test duration, emphasizing the complex hydraulic system within the samples [ABSTRACT FROM AUTHOR]

This paper focuses on a morphological study of the MnTe-like structures, carried out by the evaluation of the tortuosity tensor and other related parameters using a computational fluid dynamics approach recently developed by our research group. The present work focuses on all possible crystals—existing or not developed yet—having the same structure as that of the manganese telluride. This analysis provides new information not present yet in the open literature. The motivation behind this study lies in the importance of this type of structure in physics and material science. In particular, the structures investigated are anisotropic and bi-disperse, with two independent geometrical parameters controlling the structure shape: the ratio of the particle diameters (r1) and the normalised inter-particle distance (r2). Exploiting this fact, several different structures of the same family are created, changing these two parameters independently, also allowing inter-penetration of particles to enlarge the study's applicability. The results are primarily obtained in terms of the tortuosity tensor, needed to catch and quantify the anisotropy of the structures. Then, other morphological parameters, such as connectivity, principal diffusion directions, and anisotropy factors, are evaluated, obtaining in this way a novel morphological characterisation of the structure. It is found that high values of tortuosity are observed at lower and higher values of {r1, r2}, which means that there exists a minimum value between them. Additionally, the anisotropy factor is found to be higher at lower values of {r1, r2} and lower at higher ones. This is in accordance with the fact that, as the inter-particle distance and the ratio between particle diameters increase, the structure enlarges, which implies a lower influence of the particle distribution and, thus, a gradually more isotropic structure. [ABSTRACT FROM AUTHOR]

Localization is crucial in wireless sensor networks for various applications, such as tracking objects in outdoor environments where GPS (Global Positioning System) or prior installed infrastructure is unavailable. However, traditional techniques involve many anchor nodes, increasing costs and reducing accuracy. Existing solutions do not address the selection of appropriate anchor nodes and selecting localized nodes as assistant anchor nodes for the localization process, which is a critical element in the localization process. Furthermore, an inaccurate average hop distance significantly affects localization accuracy. We propose an improved DV-Hop algorithm based on anchor sets (AS-IDV-Hop) to improve the localization accuracy. Through simulation analysis, we validated that the AS-IDV-Hop proposed algorithm is more efficient in minimizing localization errors than existing studies. The AS-IDV-Hop algorithm provides an efficient and cost-effective solution for localization in Wireless Sensor Networks. By strategically selecting anchor and assistant anchor nodes and rectifying the average hop distance, AS-IDV-Hop demonstrated superior performance, achieving a mean accuracy of approximately 1.59, which represents about 25.44%, 38.28%, and 73.00% improvement over other algorithms, respectively. The estimated localization error is approximately 0.345, highlighting AS-IDV-Hop’s effectiveness. This substantial reduction in localization error underscores the advantages of implementing AS-IDV-Hop, particularly in complex scenarios requiring precise node localization. [ABSTRACT FROM AUTHOR]

Densities of juvenile corals (≤ 50 mm diameter) are expected to vary between geographically isolated and more spatially proximate reefs, and may constrain local recovery potential. This study compared juvenile coral densities and their relationships with local abundance of adult congenerics at geographically isolated reefs within Australia's Coral Sea Marine Park (CSMP) versus highly connected reefs within the Great Barrier Reef Marine Park (GBRMP). Three latitudinal regions and two habitats (reef crest and slope) were examined within both marine parks to test for spatial variation. Densities of juvenile corals in the CSMP (13.99 ± 0.72 juveniles 10 m−2) were significantly lower compared to those in the GBRMP (23.72 ± 1.86 juveniles 10 m−2). Specifically, there were significantly less Acropora and Pocillopora juveniles on the reef crest in the central CSMP compared to the GBRMP. Relationships between juvenile abundance and percent coral cover were greatest for Acropora and Pocillopora in the GBRMP. This may be due to the low range of coral cover estimates recorded in the CSMP, especially for Acropora (0–15%). Low juvenile coral abundance, and in particular, the lack of fast-growing juvenile corals (e.g., Acropora) in the Central CSMP, in combination with low cover of broodstock (particularly Acropora) on CSMP reefs, poses a significant constraint on post-disturbance recovery capacity, possibly attributable to isolation and limited connectivity among reefs in this region. [ABSTRACT FROM AUTHOR]

The symmetric difference of two graphs G1,G2$$ {G}_1,{G}_2 $$ on the same set of vertices V$$ V $$ is the graph on V$$ V $$ whose set of edges are all edges that belong to exactly one of the two graphs G1,G2$$ {G}_1,{G}_2 $$. For a fixed graph H$$ H $$ call a collection 풢 of spanning subgraphs of H$$ H $$ a connectivity code for H$$ H $$ if the symmetric difference of any two distinct subgraphs in 풢 is a connected spanning subgraph of H$$ H $$. It is easy to see that the maximum possible cardinality of such a collection is at most 2k′(H)≤2δ(H)$$ {2}^{k\prime (H)}\le {2}^{\delta (H)} $$, where k′(H)$$ {k}^{\prime }(H) $$ is the edge‐connectivity of H$$ H $$ and δ(H)$$ \delta (H) $$ is its minimum degree. We show that equality holds for any d$$ d $$‐regular (mild) expander, and observe that equality does not hold in several natural examples including any large cubic graph, the square of a long cycle and products of a small clique with a long cycle. [ABSTRACT FROM AUTHOR]