Distinct Patches Research Articles

Design of Enhanced Wide Band Microstrip Patch Antenna Based on Defected Ground Structures (DGS) for Sub-6 GHz Applications

In this paper a comprehensive comparative study of three distinct microstrip patch antenna (MPA) designs, each optimized for the sub-6 GHz applications, is presented. The initial design phase utilized a Rogers RT 5880 substrate with a permittivity (εr1) of 2.2 and a thickness(H1) of 1.42 mm. The proposed model achieved a resonance band ranging from 4.8 to 7 GHz, with a bandwidth of 2.2 GHz and a return loss (S11) of -20 dB. Subsequent enhancements involved integrating a Barium Strontium Titanate (BST) thin film (εr2 = 250, thickness(H2) = 0.005 mm), effectively shifting the operational band to 3.5-5.3 GHz. The final design iteration, which incorporated both BST and a Defective Ground Structure (DGS), represented a substantial advancement, achieving wideband operation from 1.8 to 6 GHz, expanding the bandwidth to 4.2 GHz, and improving the S11 to -25 dB. This integration also resulted in a compact antenna size of 30 x 26.5 x 1.42 mm³. These findings underscore the synergistic impact of BST and DGS in enhancing MPA design, marking a significant progression in antenna technology, vital for a range of wireless communication.

Weak phylogenetic effect on specialist plant assemblages and their persistence on habitat islands

AbstractAimThe influence of species phylogenetic relatedness on the formation of insular assemblages remains understudied in functional island biogeography, especially for terrestrial habitat islands (i.e. distinct habitat patches embedded in a matrix that differ in the prevailing environmental conditions). Here, we tested three eco‐evolutionary hypotheses: (1) functional specialization of species (i.e. specialism) is associated with phylogenetic clustering at the habitat archipelago scale, (2) such clustering increases with insularity at the habitat island scale and (3) traits indicative of effective local persistence strategies shape island specialism.LocationTerrestrial habitat islands, Europe (Fens in the Western Carpathians, Outcrops in Moravia and Mountaintops in the Cantabrian Range).TaxonAngiosperms.MethodsWe assessed the phylogenetic relatedness of habitat specialists in three different archipelagos composed of terrestrial habitat islands based on phylogenetic signals and phylogenetic diversity (PD) measures. We estimated the effect of insularity on PD using linear models and the effect of persistence traits on specialism using phylogenetic logistic regressions.ResultsOur hypotheses were largely not supported. Outcrop and mountaintop specialist assemblages did not exhibit any phylogenetic structuring, whereas fen specialists were clustered at the archipelago scale. Therefore, insularity seems not to act as a selective force for phylogenetic structure, and ecologically important persistence traits do not operate as precursors of specialism.Main ConclusionsOur results show that species phylogenetic relatedness plays a minor role in shaping habitat island specialist assemblages. Furthermore, the effects of phylogenetic relatedness on assemblages of island specialists are system and scale dependent. Finally, accounting for species' phylogenetic relatedness on persistence traits yielded results similar to previous studies, which corroborates the positive relationship between insularity and functional traits (indicative of enhanced plant persistence abilities with increasing within‐archipelago insularity).

The IFN-γ-CXCL9/CXCL10-CXCR3 axis in vitiligo: Pathological mechanism and treatment.

Vitiligo is a disease featuring distinct white patches that result from melanocyte destruction. The overall pathogenesis of vitiligo remains to be elucidated. Nevertheless, considerable research indicates that adaptive immune activation plays a key role in this process. Specifically, the interferon-gamma (IFN-γ), C-X-C motif chemokine ligands (CXCL9/10), and C-X-C motif chemokine receptor (CXCR3) signaling axis, collectively referred to as IFN-γ-CXCL9/10-CXCR3 or ICC axis, has emerged as a key mediator responsible for the recruitment of autoimmune CXCR3+ CD8+ T cells. These cells serve as executioners of melanocytes by promoting their detachment and apoptosis. Moreover, IFN-γ is generated by activated T cells to create a positive feedback loop, exacerbating the autoimmune response. This review not only delves into the mechanistic insights of the ICC axis but also explores the significant immunological effects of associated cytokines and their receptors. Additionally, the review provides a thorough comparison of existing and emerging treatment options that target the ICC axis for managing vitiligo. This review aims to foster further advancements in basic research within related fields and facilitate a deeper understanding of alternative treatment strategies targeting different elements of the axis.

Self-Prompting Tracking: A Fast and Efficient Tracking Pipeline for UAV Videos

In the realm of visual tracking, remote sensing videos captured by Unmanned Aerial Vehicles (UAVs) have seen significant advancements with wide applications. However, there remain challenges to conventional Transformer-based trackers in balancing tracking accuracy and inference speed. This problem is further exacerbated when Transformers are extensively implemented at larger model scales. To address this challenge, we present a fast and efficient UAV tracking framework, denoted as SiamPT, aiming to reduce the number of Transformer layers without losing the discriminative ability of the model. To realize it, we transfer the conventional prompting theories in multi-model tracking into UAV tracking, where a novel self-prompting method is proposed by utilizing the target’s inherent characteristics in the search branch to discriminate targets from the background. Specifically, a self-distribution strategy is introduced to capture feature-level relationships, which segment tokens into distinct smaller patches. Subsequently, salient tokens within the full attention map are identified as foreground targets, enabling the fusion of local region information. These fused tokens serve as prompters to enhance the identification of distractors, thereby avoiding the demand for model expansion. SiamPT has demonstrated impressive results on the UAV123 benchmark, achieving success and precision rates of 0.694 and 0.890 respectively, while maintaining an inference speed of 91.0 FPS.

Alopecia Areata's Psychological Impact on Quality of Life, Mental Health, and Work Productivity: A Scoping Review

Alopecia areata is an autoimmune disorder characterized by the abrupt loss of hair in distinct patches, which can manifest on the scalp or any other place of the body with hair. Although it is essentially a dermatological condition, its psychological effects on individuals go beyond the visible symptoms. This abstract is to provide a concise overview of the current body of literature regarding the psychological ramifications of alopecia areata, with a specific emphasis on its impact on quality of life, mental well-being, and occupational efficiency. The outward manifestation of hair loss in patients with alopecia areata has a substantial impact on their overall quality of life. The modified physical appearance frequently results in sensations of self-awareness, social isolation, and a detrimental effect on self-worth. People may face difficulties in their regular routines, such as personal grooming and getting dressed, which might worsen their overall quality of life. Individuals with alopecia areata commonly experience significant mental health consequences. The psychosocial stress linked to the disease might contribute to the onset or worsening of anxiety and depression. Research has indicated a greater occurrence of anxiety and depressed symptoms in patients with alopecia areata in comparison to the general population. The persistent nature of the illness and ambiguity around the progression of hair loss can also lead to continuous psychological discomfort. The psychological impact of alopecia areata might hurt work productivity. Workers may encounter several obstacles in their professional environment, including diminished self-assurance, heightened rates of absenteeism, and issues in establishing and maintaining interpersonal connections. Stigmatization and misunderstandings about the condition might exacerbate challenges in the workplace.

543 - Early repigmentation of stable vitiligo through point-of-care melanocyte transfer using non-cultured autologous skin cell suspension

Abstract Introduction Vitiligo is an acquired depigmenting skin condition characterized by the loss of skin pigmentation, impacting 0.5% to 2% of the global population.1–3 Vitiligo presents as distinct depigmented patches resulting from autoimmune melanocyte destruction. Individuals with visual vitiligo lesions often experience negative body image, diminished self-confidence, discomfort, and overall lower quality of life (QoL).4 While there are medical treatment options available, these can be associated with poor efficacy and low medication compliance.4 Residual lesions after treatment may require surgical intervention which allows for melanocyte transplantation from an area that is pigmented to one that is lacking functional melanocytes. Through a point-of-care device, a non-cultured autologous skin cell suspension (ACSC) can be prepared using a small skin sample; the ASCS contains healthy melanocytes and is immediately applied onto skin treated with ablative laser to aid in the repigmentation of affected areas. Objective The objective of this study was to evaluate the one-time application of ASCS, with a 1:20 donor to treatment site expansion ratio, for the safe and effective repigmentation of stable vitiligo lesions. Methods A randomized, within-subject controlled, central observer-blinded study was conducted to compare the clinical performance of laser ablation, ASCS, and NB-UVB to NB-UVB alone for repigmentation of stable vitiligo lesions in adults. Subjects received NB-UVB phototherapy on both ASCS-treated and controlled lesions as per recommended by the Vitiligo Working Group. Repigmentation of ASCS-treated and control lesions were categorized by a Central Review Committee (CRC) of blinded dermatologists as one of the following: 0%-25%, 26%-50%, 51%-79%, or 80-100%. The primary effectiveness endpoint was defined as the proportion of lesions achieving ≥80% repigmentation for ASCS-treated versus control areas at Week 24. Early regimentation was assessed at Weeks 4 and 12 as a post hoc analysis. Results A significantly higher proportion of the ASCS-treated areas (36.0%, n = 9) compared to control-treated areas (0.0%) attained ≥80% repigmentation at Week 24 (P = 0.012). At Week 4, 30.4% (n = 7/23) of ASCS-treated areas had ≥26% repigmentation compared to 4.3% (n = 1/23) in the control areas. At Week 12, 56.5% (n = 13/23) of ASCS-treated areas had ≥26% repigmentation compared to 21.7% (n = 5/23) in the control areas. At Week 24, 64% (n = 16/25) of ASCS-treated areas had ≥26% repigmentation compared to 28% (n = 7/25) in the control areas. Conclusion A one-time treatment of ASCS, with the addition of NB-UVB, can result in excellent repigmentation results by 24 weeks, with most subjects seeing ≥26% repigmentation as early as 4 to 12 weeks.

Substrate integrated waveguide-based frequency-tunable self-octaplexing antenna

This communication presents the first-ever substrate integrated waveguide (SIW)-based frequency-tunable self-octaplexing antenna (SOA) for wireless communication. The structure is arranged by implementing eight distinct patches with planar 50-ohm feedlines at the top of the SIW cavity, which realize eight distinct resonant frequencies. Independent tuning of each resonant frequency is achieved by incorporating appropriately allocated pockets in the antenna substrate, which can be filled with solid dielectrics of different permittivity. The obtained tuning range is broad, from 4.76 GHz to 9.82 GHz, with the capability of tuning each port individually. Furthermore, the port isolation (for all ports) that is better than 20.5 dB. The proposed antenna has a realized gain of 3.91, 3.2, 4.05, 4.14, 3.8, 3.37, 3.55 and 3.28 dBi when using Rogers RT-6010 for pocket filling. Furthermore, the antenna provides stable radiation characteristics with precise tuning. The proposed device is suitable for various applications, including multi-standard wireless communications, due to its small size, wide tuning range, consistent radiation patterns, and comparable isolation levels.

Early Repigmentation of Stable Vitiligo through Point-of-Care Melanocyte Transfer Using Non-Cultured Autologous Skin Cell Suspension

Introduction: Vitiligo is an acquired depigmenting skin condition characterized by the loss of skin pigmentation, impacting 0.5% to 2% of the global population.1,2 Vitiligo presents as distinct depigmented patches resulting from autoimmune melanocyte destruction. Individuals with visual vitiligo lesions often experience negative body image, diminished self-confidence, discomfort, and overall lower quality of life (QoL).3 While there are medical treatment options available, these can be associated with poor efficacy and low medication compliance.4 Residual lesions after treatment may require surgical intervention which allows for melanocyte transplantation from an area that is pigmented to one that is lacking functional melanocytes. Through a point-of-care device, a non-cultured autologous skin cell suspension (ACSC) can be prepared using a small skin sample; the ASCS contains healthy melanocytes and is immediately applied onto skin treated with ablative laser to aid in the repigmentation of affected areas. The objective of this study was to evaluate the one-time application of ASCS, with a 1:20 donor to treatment site expansion ratio, for the safe and effective repigmentation of stable vitiligo lesions. Methods: A randomized, within-subject controlled, central observer-blinded study was conducted to compare the clinical performance of laser ablation, ASCS, and NB-UVB to NB-UVB alone for repigmentation of stable vitiligo lesions in adults. Subjects received NB-UVB phototherapy on both ASCS-treated and controlled lesions as per recommended by the Vitiligo Working Group. Repigmentation of ASCS-treated and control lesions were categorized by a Central Review Committee (CRC) of blinded dermatologists as one of the following: 0%-25%, 26%-50%, 51%-79%, or 80-100%. The primary effectiveness endpoint was defined as the proportion of lesions achieving ≥80% repigmentation for ASCS-treated versus control areas at Week 24. Early regimentation was assessed at Weeks 4 and 12 as a post hoc analysis. Results: A significantly higher proportion of the ASCS-treated areas (36.0%, n = 9) compared to control-treated areas (0.0%) attained ≥80% repigmentation at Week 24 (P = 0.012). At Week 4, 30.4% (n = 7/23) of ASCS-treated areas had ≥26% repigmentation compared to 4.3% (n = 1/23) in the control areas. At Week 12, 56.5% (n = 13/23) of ASCS-treated areas had ≥26% repigmentation compared to 21.7% (n = 5/23) in the control areas. At Week 24, 64% (n = 16/25) of ASCS-treated areas had ≥26% repigmentation compared to 28% (n = 7/25) in the control areas. Conclusion: A one-time treatment of ASCS, with the addition of NB-UVB, can result in excellent repigmentation results by 24 weeks, with most subjects seeing ≥26% repigmentation as early as 4 to 12 weeks.

Assessing the functional vulnerability of woody plant communities within a large scale tropical rainforest dynamics plot.

Tropical forests are characterized by intricate mosaics of species-rich and structurally complex forest communities. Evaluating the functional vulnerability of distinct community patches is of significant importance in establishing conservation priorities within tropical forests. However, previous assessments of functional vulnerability in tropical forests have often focused solely on isolated factors or individual disturbance events, with limited consideration for a broad spectrum of disturbances and the responses of diverse species. We assessed the functional vulnerability of woody plant communities in a 60-ha dynamic plot within a tropical montane rainforest by conducting in silico simulations of a wide range disturbances. These simulations combined plant functional traits and community properties, including the distribution of functional redundancy across the entire trait space, the distribution of abundance across species, and the relationship between species trait distinctiveness and species abundance. We also investigated the spatial distribution patterns of functional vulnerability and their scale effects, and employed a spatial autoregressive model to examine the relationships between both biotic and abiotic factors and functional vulnerability at different scales. The functional vulnerability of tropical montane rainforest woody plant communities was generally high (the functional vulnerability of observed communities was very close to that of the most vulnerable virtual community, with a value of 72.41% on average at the 20m×20m quadrat scale), and they exhibited significant spatial heterogeneity. Functional vulnerability decreased with increasing spatial scale and the influence of both biotic and abiotic factors on functional vulnerability was regulated by spatial scale, with soil properties playing a dominant role. Our study provides new specific insights into the comprehensive assessment of functional vulnerability in the tropical rainforest. We highlighted that functional vulnerabilities of woody plant communities and their sensitivity to environmental factors varied significantly within and across spatial scales in the tropical rainforest landscape. Preserving and maintaining the functionality of tropical ecosystems should take into consideration the variations in functional vulnerability among different plant communities and their sensitivity to environmental factors.

Gymnocranius indicus, a new large-eye seabream from the Indian Ocean

Abstract Gymnocranius indicus sp. nov. is described as a new species of the fish subfamily Monotaxinae (Sparoidea: Lethrinidae), a group of commercially important species distributed throughout the Indo-West Pacific, on the basis of 16 specimens collected from the Indian Ocean. The new species shares the following characters with its western Pacific sibling, the eyebrowed large-eye seabream, G. superciliosus: elongate body, distinctive and conspicuous dark patch above the eye, prominent forehead, moderately forked caudal fin, its lobes slightly convex inside, flank silvery, and reddish-to-red dorsal, pectoral, anal and caudal fins. However, principal component analysis based on seven morphological variables distinguished most specimens from the Indian Ocean from G. superciliosus. The most influential variable in the analysis was the eye diameter, significantly larger in the new species than in G. superciliosus. All specimens of the new species that were examined also lacked blue ornamentation on the snout and cheek. At the mitochondrial cytochrome oxidase subunit-I locus, the mean genetic p-distance between the two species was 0.039. With Gymnocranius indicus sp. nov., the genus now includes 12 valid nominal species; three additional species remain undescribed.

Geographic atrophy: pathophysiology and current therapeutic strategies.

Geographic atrophy (GA) is an advanced stage of age-related macular degeneration (AMD) that leads to gradual and permanent vision loss. GA is characterized by the loss of photoreceptor cells and retinal pigment epithelium (RPE), leading to distinct atrophic patches in the macula, which tends to increase with time. Patients with geographic atrophy often experience a gradual and painless loss of central vision, resulting in difficulty reading, recognizing faces, or performing activities that require detailed vision. The primary risk factor for the development of geographic atrophy is advanced age; however, other risk factors, such as family history, smoking, and certain genetic variations, are also associated with AMD. Diagnosis is usually based on a comprehensive eye examination, including imaging tests such as fundus photography, optical coherence tomography (OCT), and fluorescein angiography. Numerous clinical trials are underway, targeting identified molecular pathways associated with GA that are promising. Recent approvals of Syfovre and Izervay by the FDA for the treatment of GA provide hope to affected patients. Administration of these drugs resulted in slowing the rate of progression of the disease. Though these products provide treatment benefits to the patients, they do not offer a cure for geographic atrophy and are limited in efficacy. Considering these safety concerns and limited treatment benefits, there is still a significant need for therapeutics with improved efficacy, safety profiles, and better patient compliance. This comprehensive review discusses pathophysiology, currently approved products, their limitations, and potential future treatment strategies for GA.

Coupled information networks drive honeybee (Apis mellifera) collective foraging.

Collective behaviour by eusocial insect colonies is typically achieved through multiple communication networks that produce complex behaviour at the group level but often appear to provide redundant or even competing information. A classic example occurs in honeybee (Apis mellifera) colonies, where both the dance communication system and robust scent-based mechanisms contribute to the allocation of a colony's workforce by regulating the flow of experienced foragers among known food sources. Here we analysed social connectivity patterns during the reactivation of experienced foragers to familiar feeding sites to show that these social information pathways are not simply multiple means to achieve the same end but intersect to play complementary roles in guiding forager behaviour. Using artificial feeding stations, we mimicked a natural scenario in which two forager groups were simultaneously collecting from distinct patches containing different flowering species. We then observed the reactivation of these groups at their familiar feeding sites after interrupting their foraging. Social network analysis revealed that temporarily unemployed individuals interacted more often and for longer with foragers that advertised a familiar versus unfamiliar foraging site. Due to such resource-based assortative mixing, network-based diffusion analysis estimated that reactivation events primarily resulted from interactions among bees that had been trained to the same feeding station and less so from different-feeder interactions. Both scent- and dance-based interactions strongly contributed to reactivation decisions. However, each bout of dance-following had an especially strong effect on a follower's likelihood of reactivation, particularly when dances indicated locations familiar to followers. Our findings illustrate how honeybee foragers can alter their social connectivity in ways that are likely to enhance collective outcomes by enabling foragers to rapidly access up-to-date information about familiar foraging sites. In addition, our results highlight how reliance on multiple communication mechanisms enables social insect workers to utilise flexible information-use strategies that are robust to variation in the availability of social information.

X-LDA: An interpretable and knowledge-informed heterogeneous graph learning framework for LncRNA-disease association prediction

The identification of disease-related long noncoding RNAs (lncRNAs) is beneficial to unravel the intricacies of gene expression regulation and epigenetic signatures. Computational methods provide a cost-effective means to explore lncRNA-disease associations (LDAs). However, these methods often lack interpretability, leaving their predictions less convincing to biological and medical researchers. We propose an interpretable and knowledge-informed heterogeneous graph learning framework based on graph patch convolution and integrated gradients to predict LDAs and provides intuitive explanations for its predictions, called X-LDA. The heterogeneous graph is the foundation of the predictions of LDAs, we construct the knowledge-informed heterogeneous graph including LDAs drawn from biological experiments, lncRNA similarities rooted in gene sequences, disease similarities constructed based on disease categorizations. To integrate diverse biological premises and facilitate interpretability, we define nine distinct graph patch types, which encapsulate essential topological relationships within lncRNA-disease node pairs. X-LDA is designed to employ parameter sharing and multi-convolution kernels to grasp common and multiple perspectives of the graph patches, respectively. This approach culminates in the fusion of various semantic information into context embeddings. These post-hoc explanations hinge on graph patch features and integrated gradients, shedding light on the underlying factors driving predictions. Cross validation experiment on the dataset curated from databases and literatures demonstrates that the superior performance of X-LDA in comparison to nine state-of-the-art methods of three categories. X-LDA achieves a larger average area under the receiver operating curve 0.9891 (by at least 6.68%), and a larger average area under the precision–recall curve 0.7907 (by at least 23.2%) than competitive methods. The results of our well-designed ablation and interpretability experiments and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis demonstrate X-LDA’s robustness, learnability, predictability, and interpretability. The applicability of X-LDA is also demonstrated through a case study involving the investigation of associated lncRNAs in prostate cancer, colorectal cancer, and breast cancer.

Introducing desirable patches to initiate ecosystem transitions and accelerate ecosystem restoration.

Meeting restoration targets may require active strategies to accelerate natural regeneration rates or overcome the resilience associated with degraded ecosystem states. Introducing desired ecosystem patches in degraded landscapes constitutes a promising active restoration strategy, with various mechanisms potentially causing these patches to become foci from which desired species can re-establish throughout the landscape. This study considers three mechanisms previously identified as potential drivers of introduced patch dynamics: autocatalytic nucleation, directed dispersal, and resource concentration. These mechanisms reflect qualitatively different positive feedbacks. We developed an ecological model framework that compared how the occurrence of each mechanism was reflected in spatio-temporal patch dynamics. We then analyzed the implications of these relationships for optimal restoration design. We found that patch expansion accelerated over time when driven by the autocatalytic nucleation mechanism, while patch expansion driven by the directed dispersal or resource concentration mechanisms decelerated over time. Additionally, when driven by autocatalytic nucleation, patch expansion was independent of patch position in the landscape. However, the proximity of other patches affected patch expansion either positively or negatively when driven by directed dispersal or resource concentration. For autocatalytic nucleation, introducing many small patches was a favorable strategy, provided that each individual patch exceeded a critical patch size. Introducing a single patch or a few large patches was the most effective restoration strategy to initiate the directed dispersal mechanism. Introducing many small patches was the most effective strategy for reaching restored ecosystem states driven by a resource concentration mechanism. Our model results suggest that introducing desirable patches can substantially accelerate ecosystem restoration, or even induce a critical transition from an otherwise stable degraded state toward a desired ecosystem state. However, the potential of this type of restoration strategy for a particular ecosystem may strongly depend on the mechanism driving patch dynamics. In turn, which mechanism drives patch dynamics may affect the optimal spatial design of an active restoration strategy. Each of the three mechanisms considered reflects distinct spatio-temporal patch dynamics, providing novel opportunities for empirically identifying key mechanisms, and restoration designs that introduce desired patches in degraded landscapes according to these patch dynamics.

Vegetation patch dynamics in rangelands: How feedbacks between large herbivores, vegetation and soil fauna alter patches over space and through time

AbstractAimLarge herbivore grazing is a popular conservation management tool to promote vegetation structural diversity of rangelands. However, vegetation patch dynamics, that is, how patches of grazing‐defended tall vegetation and grazer‐preferred short lawns shift over space and time, is poorly understood. Here, we describe a new conceptual framework for patch dynamics within rangelands, combining theories of classical cyclical succession, self‐organization and multitrophic feedbacks between grazers, vegetation and bioturbating soil fauna.LocationWe use the cattle‐grazed salt marsh of the island Schiermonnikoog, The Netherlands, as a model system. The grazed salt marsh is characterized by distinct tall vegetation patches dominated by the grazing‐defended rush Juncus maritimus and grazing‐intolerant grass Elytrigia atherica, surrounded by a matrix of grazing lawn (dominated by Festuca rubra).The FrameworkBased on previous observational and experimental studies, we propose a cyclical patch dynamic where plant species composition and structure transitions through four phases: patch initiation (a) occurs when the grazing‐defended rush J. maritimus establishes in the grazed lawn. Patch establishment (b) follows when the grazing‐intolerant grass E. atherica establishes in the patch due to associational defence by J. maritimus and produces a large amount of litter that attracts the key bioturbating amphipod Orchestia gammarellus. Patch expansion (c) occurs when O. gammarellus activities improve soil properties of the patch, which favours E. atherica growth, leading to E. atherica competitively displacing J. maritimus in the centre of the patch. Patch degeneration (d) follows when cattle enter the enlarged patch to consume E. atherica in the centre, trample the soil, displace O. gammarellus and decrease vegetation cover, opening space for grazing‐lawn species to invade. The cycle restarts when remnants of the rush J. maritimus in the degenerated patches (or individuals recently established from seed dispersal) initiate new patches in the grazing lawn.SynthesisOur proposed patch‐dynamic model provides a means to describe the mechanisms driving vegetation patch dynamics and serves as a foundation for further experimental and observational exploration, not only for this specific system, but more generally for grazed systems worldwide that show patches of typical grazing‐defended and grazer‐preferred vegetation.

Sacred Groves as the Source of Local Medicinal Plants and Sites of Biodiversity Conservation in North 24 Parganas, West Bengal

A Sacred Grove (SG) is any grove of trees, shrubs and even herbs of special religious importance to a particular culture. SGs are consideredas distinct patches of vegetation (ranging in size from a small cluster of a few trees to a large forest stand spanning several hundredacres) which are venerated in the name of local deities or ancestral spirits, promoting conservation. Conservation of biodiversity insacred groves is a consequence of the sacred physical space of the sacred grove which is communally shared as commons and used toobserve crucial social ceremonies in indigenous societies. While documenting the sacred groves in the district of North 24 Parganas ofWest Bengal through a detailed field survey, plants of local medicinal importance were identified in these patches in which the localpeople traditionally conserved the medicinal plants since time immemorial. An extensive field survey to potential district areas anddocumentation of major flora, including their correct identification and their related Traditional Knowledge (TK) in each SG was done.More than 120 local medicinal plants were found and traditional knowledge associated with these plants was documented whichincluded Adhatoda vasica, Abroma agustum, Andrographis paniculata, Bacopa monnieri, Centella asiatica, Cocculus hirsutus, Gloriosasuperba, Tinospora cordifolia to name very few. Out of these purified aqueous extract of Cocculus hirsutus has also been reported inCOVID-19 treatment in many research papers. Traditional knowledge associated with these plants found in the sacred groves is a hiddentreasure from where further research, learning and dissemination of potential information can ensue. These SGs are examples of in-situconservation traditionally by local people and gene pool for various medicinal plants.

Chemical and population genetic analysis show no evidence of ecotype formation in a European population of the parasitoid wasp Nasonia vitripennis

Ecotypes, subpopulations or strains of a single species locally adapted to divergent ecological conditions within the same habitat are often considered to be the first steps in sympatric speciation. It has been suggested that two ecotypes are distinguishable in Nasonia vitripennis, a prominent model organism for parasitic Hymenoptera, with one ecotype parasitizing fly pupae in bird nests, and the other one parasitizing fly pupae on carrion. This differentiation into two ecotypes has been hypothesized to indicate incipient sympatric speciation in populations of this globally distributed species. In the present study, we investigated the differentiation into these two distinct ecotypes focusing on chemical profiles and the population genetic divergence in a wild N. vitripennis population from the Netherlands. Isofemale lines were obtained from bird nest boxes and from deer carrion, respectively, representing both microhabitats. To test for phenotypic differentiation, we determined the surface cuticular hydrocarbon (CHC) profiles from wasps of both host patches. Using a panel of 14 microsatellites, we concordantly determined the population genetic structure and tested for genetic differentiation between foundresses obtained from both microhabitats. Both the phenotypic as well as the genetic datasets show no evidence for any kind of separation based on the postulated two ecotypes, but rather suggest free interbreeding with no gene flow interruption between the two distinct host patches. Our findings challenge previous assumptions on clearly distinguishable ecotypes in N. vitripennis, and demonstrate how a chemical ecological assessment coupled with population genetics can be instrumental in re-evaluating the potential of ecological differentiation and incipient speciation mechanisms in parasitoid wasps.

Blast from the past: a study of decades-old fungal cultures resolves a long-standing tree disease mystery

A root disease in plantations of Pinus radiata and Pinus pinaster, where trees died in distinct patches, was present in the Western Cape province of South Africa during the 1970s and 1980s. Phytophthora cinnamomi was initially believed to be the cause, but the disease was later ascribed to the insect-associated fungus Leptographium serpens, a fungal species residing in the Ophiostomatales. Doubt regarding the cause of the disease was raised in a later study due to the fact that most Leptographium spp., particularly those that colonise ray parenchyma tissues, which is the case for L. serpens, are not typically primary disease agents. In this study, cultures of an unidentified sterile fungus collected from the dying trees were revived and identified using DNA sequencing methods, which were not available when the disease was first studied. These cultures were identified as the pyrophillic pathogen Rhizina undulata, well-known to cause patch death of conifers in South Africa and elsewhere in the world. While the patches of dying trees no longer exist and the disease cannot be newly studied, it is most likely that the tree death originally thought to be caused by L. serpens was due primarily to R. undulata. The study provides a vivid example of the value of preserving cultures of fungi for later study and the power of modern techniques to identify fungal pathogens.

The spatial distribution of insect communities of a mountaintop forest archipelago is not correlated with landscape structure: A multitaxa approach

Abstract Understanding community assembly in habitat patches requires an integrative approach, considering the potential role of local and regional factors and organisms' dispersal abilities among patches. For this, assessing the degree of species overlap between patches (nestedness) can be particularly informative, especially regarding different taxa and distinct patch properties. We assessed the potential role of landscape‐patch structure in shaping the nestedness patterns of five taxonomic groups with distinct dispersal abilities (ants, bees, dung beetles, fruit‐feeding butterflies and aculeate wasps). We collected insects from 11 forest patches in the Espinhaço mountain range in southeast Brazil. We assessed the potential contribution of three forest island attributes (size, distance and shape) to the nestedness of insect communities and then tested if metacommunities were significantly nested with respect to habitat (forest islands). Finally, we evaluated how species of each taxonomic group contribute to metacommunity nestedness. While there was a substantial variation in the contribution to the nested pattern within each taxon, all taxa studied exhibited a significantly nested pattern of species distribution. The landscape‐patch structure and the vagility of the different taxa did not influence the contribution of sites to the metacommunity nested pattern. Our integrative approach provides critical data on the role of different factors in shaping species distribution in natural patches. Species with different dispersal abilities and patches with distinct landscape properties contributed similarly to nestedness, indicating the potential role of the vegetation matrix permeability in shaping the distribution of organisms in the studied forest archipelago.

Structural polymorphisms within a common powdery mildew effector scaffold as a driver of coevolution with cereal immune receptors

In plants, host-pathogen coevolution often manifests in reciprocal, adaptive genetic changes through variations in host nucleotide-binding leucine-rich repeat immune receptors (NLRs) and virulence-promoting pathogen effectors. In grass powdery mildew (PM) fungi, an extreme expansion of a RNase-like effector family, termed RALPH, dominates the effector repertoire, with some members recognized as avirulence (AVR) effectors by cereal NLR receptors. We report the structures of the sequence-unrelated barley PM effectors AVRA6, AVRA7, and allelic AVRA10/AVRA22 variants, which are detected by highly sequence-related barley NLRs MLA6, MLA7, MLA10, and MLA22 and of wheat PM AVRPM2 detected by the unrelated wheat NLR PM2. The AVR effectors adopt a common scaffold, which is shared with the RNase T1/F1 family. We found striking variations in the number, position, and length of individual structural elements between RALPH AVRs, which is associated with a differentiation of RALPH effector subfamilies. We show that all RALPH AVRs tested have lost nuclease and synthetase activities of the RNase T1/F1 family and lack significant binding to RNA, implying that their virulence activities are associated with neo-functionalization events. Structure-guided mutagenesis identified six AVRA6 residues that are sufficient to turn a sequence-diverged member of the same RALPH subfamily into an effector specifically detected by MLA6. Similar structure-guided information for AVRA10 and AVRA22 indicates that MLA receptors detect largely distinct effector surface patches. Thus, coupling of sequence and structural polymorphisms within the RALPH scaffold of PMs facilitated escape from NLR recognition and potential acquisition of diverse virulence functions.