Single Island Research Articles

Shedding light on dark taxa in sky‐island Appalachian leaf litter: Assessing patterns of endemicity using large‐scale, voucher‐based barcoding

Abstract Developing systematic conservation plans depends on a wealth of information on a region's biodiversity. For ‘dark taxa' such as arthropods, such data are usually very incomplete and in most cases left out from assessments. Sky islands are important and often fragile biodiversity hotspots. Southern Appalachian high‐elevation spruce–fir forests represent a particularly threatened sky‐island ecosystem, hosting numerous endemic and threatened species, but their arthropods remain understudied. Here we use voucher‐based megabarcoding to explore genetic differentiation among leaf‐litter arthropod communities of these highlands, and to examine the extent to which they represent dispersed communities of more or less coherent species, manageable as a distributed unit. We assembled a dataset comprising more than 6000 COI sequences representing diverse arthropod groups to assess species richness and sharing across peaks and ranges. Comparisons were standardised across taxa using automated species delimitation, measuring endemism levels by putative species. Species richness was high, with sites hosting from 86 to 199 litter arthropod species (not including mites or myriapods). Community profiles suggest that around one fourth of these species are unique to single sky islands and more than one third of all species are limited to a particular range. Across major taxa, endemicity was lowest in Araneae, and highest in neglected groups like Isopoda, Pseudoscorpionida, Protura and Diplura. Southern Appalachian sky islands of spruce–fir habitat host significantly distinct leaf‐litter arthropod communities, with high levels of local endemicity. This is the first work to provide such a clear picture of peak and range uniqueness for a taxonomically broad sample. Ensuring the protection of a sizeable fraction of high‐elevation litter species richness will therefore require attention at a relatively fine spatial scale.

Non-Native Marine Macroalgae of the Azores: An Updated Inventory

Non-native species (NNS) represent a threat to biodiversity, and their occurrence and distribution should be periodically updated and made easily available to researchers and policymakers. An updated inventory of macroalgal NNS currently present in the Azores was produced based on published reports. Data concerning the first report and the distribution in the archipelago are provided for each species, as well as their respective native ranges and possible vectors of introduction. The resulting list comprises 42 taxa, i.e., 8.05% of the marine flora presently reported in the Azores, with 16 new NNS recorded over the last decade. The most isolated islands of the Western Group presented lower numbers of NNS (4.25% and 6.25%). In contrast, the two islands with the most used marina for transatlantic recreational sailing presented higher numbers (12.90% and 16.87%). Shipping is the main introduction vector (68%), whereas most macroalgal NNS are originally from the Pacific Ocean (31%) and the Indo-Pacific (31%). The presence of 13 species is restricted to single islands, and no species is reported exclusively in the Western group. Asparagopsis armata is the only algal NNS reported from all islands of the Azores. Future work is proposed to support policymaking.

Hypometabolic patterns of focal cortical dysplasia in PET-MRI co-registration imaging: a retrospective evaluation in a series of 83 patients.

To characterize the PET-MRI co-registration of hypometabolic patterns in focal cortical dysplasia (FCD) types I and II and provide some suggestions in presurgical evaluation of epilepsy surgery. We retrospectively analyzed PET-MRI co-registration imaging data from a cohort of 83 epilepsy patients with histologically confirmed FCD types I and II. Hypometabolic patterns were classified into 4 types: bottom of sulcus hypometabolism (BOSH), single island of sulcus hypometabolism (SIOS), single gyrus or sulcus hypometabolism (SGOS), and multiple gyri and sulci hypometabolism (MGOS). Most of cases that were overlooked by conventional MRI and PET evaluation but positive in PET-MRI co-registration were focalized lesions in dorsolateral frontal lobe (9/15) and FCD type IIa was the most prevalent pathological type (11/15). The FCD histological types (p = 0.027) and locations (p < 0.001) were independent predictors of PET-MRI co-registration hypometabolic patterns. Focalized hypometabolic patterns (BOSH, SIOS, SGOS) were primarily observed in the frontal lobe (33/39) and FCD type II (43/62) and extensive pattern (MGOS) in temporal lobe (18/20) and FCD type I (16/21; p < 0.005). PET-MRI co-registration enhanced the detection of FCD type IIa compared with conventional MRI and PET reading. The hypometabolic patterns of FCD type I and temporal lobe FCD were more extensive than those of FCD type II and frontal lobe FCD, respectively. The predilection of focalized hypometabolic patterns in frontal lobe FCD suggested that subtle lesions should be checked carefully in patients with suspected frontal lobe epilepsy.

Effect of Twin Island Configuration on Airwake Aerodynamics over Generic Aircraft Carrier using CFD

The technological advancements have led to the evolution of numerous concepts in an aircraft carrier’s topdeck design, the twin island concept being the latest entrant. An aircraft carrier’s bluff body geometry presents many challenges to the pilot, landing on deck being the most critical. The present study aims to undertake a computational investigation of the aerodynamic analysis of a Twin Island GAC (Generic Aircraft Carrier) conceptualized vis- à-vis its base variant. The flow over the twin island GAC flight deck and downstream is analysed using various transverse planes perpendicular to the flow direction as detailed in the paper. Subsequently, a parametric study was undertaken for understanding the effects of longitudinal translations of the two islands with respect to the baseline GAC position. The results depict the advantage of certain variants of twin islands over a single island, and ~68 % reduction in turbulence is achieved along the glideslope by one of the variations which could aid in reducing pilot workload. The data can act as a catalyst for utilization and incorporation in future floating platform designs and further studies in this field.

Phylogenetic relationships of Cuban and Caribbean Plumeria (Apocynaceae) based on the plastid genome

Abstract Plumeria L. (Apocynaceae) is a Neotropical genus mostly restricted to the Caribbean, which is cultivated in tropical gardens worldwide. Almost all ~27 species are endemic to the Caribbean Islands, except for four (Plumeria inodora Jacq., Plumeria obtusa L., Plumeria pudica Jacq., and Plumeria rubra L.) that are native to Central America and northern South America. Cuba harbours the largest diversity of the genus, with 13 endemic species. We present the first molecular phylogeny of the genus based on the nucleotide sequences of the complete plastid genome. Partial plastid genomes of 11 Plumeria species and one closely related species (Himatanthus sp.) were sequenced using long-PCR and next-generation sequencing. The recovered clades mostly grouped by single islands or closely neighboring islands. The phylogenetic relationships indicate patterns of adaptive radiation, with ecological shifts within these island-based clades and a west-to-east colonization route in the region. Plumeria rubra and Himatanthus sp. were resolved as sister to the rest of the genus. One unexpected finding was that P. pudica, a species restricted to the southern Caribbean Basin mainland, was recovered within the clade containing the Caribbean Island endemics, rendering the endemic group polyphyletic. Our study provides a phylogenetic framework for future studies that will need to include nuclear molecular markers and a more extensive sampling.

DNA barcodes of the Greater Antillean butterflies (Lepidoptera: Papilionoidea) suggest a richer, more isolated fauna and higher endemism

Abstract We provide the first comprehensive assessment of the Greater Antilles butterfly fauna from a molecular perspective. We gathered COI barcodes for 82% of the archipelago’s 367 species. Barcodes perform relatively well for species identification. A barcode gap separates 83% of the 270 species (represented by at least two sequences) from its nearest neighbour (NN). Of the 31 species represented by single barcodes, 26 have minimum distances from their NN above 2%. Maximum intraspecific distances are higher than 2% for 57 species (21%); however, values are lower within single islands suggesting that a part of these species has evolved into endemic lineages overlooked or unrecognized until today. Barcodes are diagnostic for only 80 of the currently accepted 180 subspecies represented by at least two sequences suggesting numerous conflicts with the infraspecific classification and highlighting its subjectivity. For 20 species, and several subspecies within them, we propose a split into two or more species and elevating several subspecies to the species category. Other data sources including novel or previously ignored morphological characters of adults and immature stages, natural history and/or additional nuclear sequences support these taxonomic changes.

Numeric assessment of the effect of the twin island design on the airflow dynamics around a generic aircraft carrier

The twin island concept is the most recent innovation in the top-deck architecture of an aircraft carrier. The carrier’s bluff body design presents the pilot with a number of difficulties, with landing on deck posing the biggest problem. The goal of the current study is to carry out the numerical analysis of the aerodynamic behaviour of twin island structure on Generic Aircraft Carrier. The flow characterization has been performed utilizing the normalized axial velocity and turbulent kinetic energy as aids for establishing pilot workload along the glideslope line. In this paper, multiple transverse planes cut across perpendicular to the flow direction are used to analyse the flow across the flight deck of twin island GAC and its downstream. The impacts of the two islands’ longitudinal translations with regard to the initial GAC position were then investigated and the results were analysed and compiled with reference to the landing approach path of the aircraft. The results show that the twin island designs are preferable to a single island. The maximum advantage in terms of turbulence reduction is achieved when the bifurcated islands are longitudinally repositioned forward of the original single island design position. The modified design not only achieves a 72% reduction in peak turbulence but also provides an additional time advantage to the pilot for assessing the environmental conditions while he is approaching the carrier flight deck for landing thus aiding to efficiently and effectively manage the workload. The findings of this study can act as a driving force for the integration and application of twin island concept in future design plans for floating structures and further studies in the field.

Study and Modeling of the Kinetics of the Photocatalytic Destruction of Stearic Acid Islands on TiO2 Films.

The kinetics of the removal of stearic acid (SA) islands by photocatalytic coatings is controversial, with some reporting that the islands fade as their thickness, h, decreases with the irradiation time, t, but maintain a constant area, a, -da/dt = 0, and others reporting that -dh/dt = 0 and -da/dt = -constant, i.e., the islands shrink, rather than fade. This study attempts to understand the possible cause for these two very different observations through a study of the destruction of a cylindrical SA island and an array of such islands, on two different photocatalytic films, namely, Activ self-cleaning glass, and a P25 TiO2 coating on glass, which have established uniform and heterogeneous surface activities, respectively. In both cases, using optical microscopy and profilometry, it is shown that, irrespective of whether there is as a single cylindrical island or an array of islands, h decreases uniformly with t, -dh/dt = constant, and -da/dt = 0, so that the SA islands just fade. However, in a study of the photocatalyzed removal of SA islands with a volcano-shaped profile, rather than that of a cylinder, it is found that the islands shrink and fade. A simple 2D kinetic model is used to rationalize the results reported in this work. Possible reasons for the two very different kinetic behaviors are discussed. The relevance of this work to self-cleaning photocatalytic films is discussed briefly.

Impact of Local Composition on the Emission Spectra of InGaN Quantum-Dot LEDs.

A possible solution for the realization of high-efficiency visible light-emitting diodes (LEDs) exploits InGaN-quantum-dot-based active regions. However, the role of local composition fluctuations inside the quantum dots and their effect of the device characteristics have not yet been examined in sufficient detail. Here, we present numerical simulations of a quantum-dot structure restored from an experimental high-resolution transmission electron microscopy image. A single InGaN island with the size of ten nanometers and nonuniform indium content distribution is analyzed. A number of two- and three-dimensional models of the quantum dot are derived from the experimental image by a special numerical algorithm, which enables electromechanical, continuum k→·p→, and empirical tight-binding calculations, including emission spectra prediction. Effectiveness of continuous and atomistic approaches are compared, and the impact of InGaN composition fluctuations on the ground-state electron and hole wave functions and quantum dot emission spectrum is analyzed in detail. Finally, comparison of the predicted spectrum with the experimental one is performed to assess the applicability of various simulation approaches.

Novel technique to control the focal spot size using carbon nanotube based cold cathode electron beam (C-beam) architecture

This article discusses the development of a cold cathode electron beam (C-beam) based on vertically aligned carbon nanotubes (VACNTs) and the optimization of field emission (FE) from C-beam architecture design. The characteristics of the electron beam are typically required to match the applications of interest. To study the FE, five distinct multi-array emitter island designs, viz., 65 × 65, 75 × 75, 90 × 90, 100 × 100, and 240 × 240 μm2, were fabricated. The island 240 × 240 μm2 (single island) was divided into a group of four subislands each with dimensions 65 × 65, 75 × 75, 90 × 90, and 100 × 100 μm2. We explored the field-screening effect of these different island designs using experiments and modeling, and we discovered that the size of the island had a significant impact on the FE properties. Moreover, we found that the island’s size significantly affected its I–V properties, with a 75 × 75 μm2 island offering 0.7 mA anode current the best emission current among other islands. Additionally, tungsten cross wire (EN 12543-5), a typical resolution testing object, had its focal spot size (FSS) measured using x-ray imaging, and the lowest FSS of 0.45 and 0.49 mm in both vertical and horizontal directions was obtained. This innovative method has a great deal of promise for developing the next generation of VACNT-based electron sources.

The role of methylation of glutamate dehydrogenase gene promoters (&lt;i&gt;GDH1&lt;/i&gt; and &lt;i&gt;GDH2&lt;/i&gt;) in the regulation of their expression in corn leaves under hypoxia

The regulation of glutamate dehydrogenase, an enzyme that is involved in both nitrogen and carbon metabolism, and also links between the tricarboxylic acid cycle and the -aminobutyric acid shunt, has been studied. It was found that oxygen deficiency-induced changes in glutamate dehydrogenase activity in maize leaves (Zea mays L.) are to increase its catalytic activity by more than twice. Differential expression of genes was studied by real-time PCR in GDH1 and GDH2, which encode the - and -subunits of glutamate dehydrogenase, respectively, in the maize genome. Decreased relative level of gene transcripts GDH2 was accompanied by an increase in the expression activity of the gene GDH1. This, in turn, presumably promoted the amination reaction of 2-oxoglutarate. In the promoter of the gene GDH2, the presence of two CpG islands 404 and 383 bp in size was found. Gene promoter GDH1 does not contain a single CpG island; however, 38% of the CpNpG and CpNpN sites of the total number of studied dinucleotides in its composition were found. To assess the influence of the degree of methylation of individual CpG dinucleotides that are part of the promoter regions of genes GDH1 and GDH2 on their expression under hypoxic conditions, a comparative analysis of the dynamics of the transcriptional activity of the genes of - and -subunits of glutamate dehydrogenase from the methyl status of their promoters was carried out. Inversely proportional superposition of changes in the methylation profile of gene promoters GDH1 and GDH2 and transformation of the level of expression of these genes shows their correlation. The data obtained as a result of methyl-specific PCR indicate that an increase in the proportion of methylated CpG dinucleotides leads to a decrease in the amount of mRNA of the gene GDH2, while a decrease in this value for the gene GDH1 causes the induction of its functioning. Methylation of promoter regions of glutamate dehydrogenase genes regulates their transcriptional activity in maize leaves in vivo under conditions of oxygen deficiency. Thus, the little data on the molecular mechanisms of regulation of the synthesis of glutamate dehydrogenase isoenzymes were supplemented by new results on the role of the degree of methylation of gene promoters GDH1 and GDH2 glutamate dehydrogenases in their differential expression during maizes adaptation to hypoxia.

Inter- and intra-island speciation and their morphological and ecological correlates in Aeonium (Crassulaceae), a species-rich Macaronesian radiation.

The most species-rich and ecologically diverse plant radiation on the Canary Islands is the Aeonium alliance (Crassulaceae). In island radiations like this, speciation can take place either within islands or following dispersal between islands. Aiming at quantifying intra- and inter-island speciation events in the evolution of Aeonium, and exploring their consequences, we hypothesized that (1) intra-island diversification resulted in stronger ecological divergence of sister lineages, and that (2) taxa on islands with a longer history of habitation by Aeonium show stronger ecological differentiation and produce fewer natural hybrids. We studied the biogeographical and ecological setting of diversification processes in Aeonium with a fully sampled and dated phylogeny inferred using a ddRADseq approach. Ancestral areas and biogeographical events were reconstructed in BioGeoBEARS. Eleven morphological characters and three habitat characteristics were taken into account to quantify the morphological and ecological divergence between sister lineages. A co-occurrence matrix of all Aeonium taxa is presented to assess the spatial separation of taxa on each island. We found intra- and inter-island diversification events in almost equal numbers. In lineages that diversified within single islands, morphological and ecological divergence was more pronounced than in lineages derived from inter-island diversification, but only the difference in morphological divergence was significant. Those islands with the longest history of habitation by Aeonium had the lowest percentages of co-occurring and hybridizing taxon pairs compared with islands where Aeonium arrived later. Our findings illustrate the importance of both inter- and intra-island speciation, the latter of which is potentially sympatric speciation. Speciation on the same island entailed significantly higher levels of morphological divergence compared with inter-island speciation, but ecological divergence was not significantly different. Longer periods of shared island habitation resulted in the evolution of a higher degree of spatial separation and stronger reproductive barriers.

The circadian demethylation of a unique intronic deoxymethylCpG-rich island boosts the transcription of its cognate circadian clock output gene

We demonstrate that there is a tight functional relationship between two highly evolutionary conserved cell processes, i.e., the circadian clock(CC) and the circadian DNA demethylation-methylation of cognate deoxyCpG-rich islands. We have discovered that every circadian clock-controlled output gene (CCG), but not the core clock nor its immediate-output genes, contains a single cognate intronic deoxyCpG-rich island, the demethylation-methylation of which is controlled by the CC. During the transcriptional activation period, these intronic islands are demethylated and, upon dimerization of two YY1 protein binding sites located upstream to the transcriptional enhancer and downstream from the deoxyCpG-rich island, store activating components initially assembled on a cognate active enhancer (a RORE, a D-box or an E-box), in keeping with the generation of a transcriptionally active condensate that boosts the initiation of transcription of their cognate pre-mRNAs. We report how these single intronic deoxyCpG-rich islands are instrumental in such a circadian activation/repression transcriptional process.

Performance of staggered bit island spacing adjustment for a SRTR BPMR system

One of the key problems facing the designer of data storage devices is how to handle the exponential rise in demand for information storage. To enhance the storage capacity of bit-patterned magnetic recording (BPMR) that stores one data bit in a single magnetic island, the spacing among bit islands, i.e., bit period and track pitch, must be reduced. However, the interference effects from both the across- and along-track directions are unavoidably increased, which leads to performance degradation. This paper proposes to utilize the proper spacing arrangement of magnetic islands for a single-reader two-track reading scheme to increase the staggered BPMR system’s storage capacity. We also study how the system performs for different distances between magnetic islands when track misregistration and media noise are present. Simulation results reveal that the staggered BPMR system with an appropriate magnetic island spacing can provide better performance than the traditional island placement, where the spacing between bit islands in across- and along-track directions is same.

Island life accelerates geographic radiation in the white‐eyes (Zosteropidae)

White‐eyes are an iconic avian radiation of small passerines that are mainly distributed across the eastern hemisphere tropics and subtropics. Species diversity of white‐eyes is particularly high on oceanic islands, and many species are restricted to single islands or island groups. The high rate of species diversification of white‐eyes ranks them among the fastest radiations known in birds, but whether their accelerated diversification was the result of repeatedly colonizing islands remains unexplored. We used a newly estimated timetree for nearly all zosteropids and phylogenetic comparative methods to estimate and compare diversification rates between island and continental lineages. We show that island white‐eyes have similar extinction rates, yet higher speciation rates compared with continental white‐eyes. In addition, we find higher rates of transitions from islands to continents. Our results show the importance of islands, such as Wallacean and Melanesian archipelagos of the Indo‐Pacific, in facilitating high rates of speciation within this remarkable clade.

Measuring the island tourism development sustainability at dual spatial scales using a four-dimensional model: A case study of Shengsi archipelago, China

Measuring the island tourism development sustainability is critical for utilizing the island tourism resources, improving the island's socioeconomic prosperity, and maintaining its ecosystem but challenging due to the complex factors and their spatial heterogeneities. In the present study, a model was established for comprehensively measuring the island tourism development sustainability. The model is composed of four dimensions, namely, tourism attractions, ecological resilience, traffic accessibility, and accommodation capacity, and their spatial heterogeneities at dual spatial scales, i.e., evaluation unit and single island scales. An island tourism development sustainability composite index (ITDSCI, 0–5, dimensionless) was proposed to integrate the four dimensions at the dual scales. Remote sensing, field survey, and statistical data served as the data source, and the geographic information system was used to realize the spatial exhibitions of evaluation results. An important island tourism destination in China, Shengsi Archipelago, was selected to demonstrate the model. The results indicated the distinct heterogeneities of ITDSCI at the dual spatial scales. At evaluation unit scale, ITDSCI ranged from 0 to 5 with 2.21 as the mean value. Within each of the dimensions, point and line resources contributed much more than area resources to the tourism attractions; anthropogenic influence played a dominant role in changing the ecological resilience; and the external and internal traffic were both crucial for traffic accessibility. The four dimensions jointly determined the ITDSCI, with traffic accessibility and tourism attractions making larger contributions than the remaining two dimensions. At single island scale, ITDSCI ranged from 0 to 3.45 with 1.39 as the mean value; it distinctly increased with the increase in island area and shape complexity. Larger islands generally had more point resources and better traffic conditions, while islands with more complex shapes and higher isolation usually contained more line and area resources, respectively. Then, spatial mismatch analyses among the four dimensions revealed the urgency to improve the ecological resilience, and suggestions for coordinating the four dimensions were proposed in scopes of the entire archipelago and the contrasting sub-regions. The empirical study verified the non-collinearity among the four dimensions and validated the effectiveness and applicability of the model in comprehensively measuring the spatial heterogeneity of island tourism development sustainability.

Low genetic diversity in a widespread whistling alien: A comparison of Eleutherodactylus johnstonei Barbour, 1914 (Eleutherodactylidae) and congeners in native and introduced ranges

There is no clear empirical evidence to support the general assumption that genetic diversity favours successful invasions. Many invading species disperse and establish successfully despite low genetic diversity, a phenomenon known as the genetic paradox of biological invasion. Model systems that allow comparison of genetic patterns between exotic and native source populations are still scarce. This is particularly true for amphibians. Here we compare genetic patterns of the widely introduced Johnstone’s Whistling Frog, Eleutherodactylus johnstonei, with its successful alien congener E. antillensis and the single island endemic E. portoricensis. Genetic diversity and population differentiation in native and introduced populations of the three taxa were inferred from mitochondrial D-loop sequences (235 bp). Our results reveal that exotic populations of the two alien taxa, E. johnstonei and E. antillensis, are not only genetically impoverished due to founder effects, but that, moreover, their native range source-populations exhibit low genetic diversity and inter-population differentiation in the first place. Populations of the endemic E. portoricensis, on the other hand, are genetically more diverse and show marked inter-population differentiation. These observed genetic patterns are consistent with geological processes and invasion histories. We argue that the establishment success of the alien taxa in our model system is better explained by ecological factors and anthropogenic drivers than by genetic diversity. As these factors provide more parsimonious explanations, they should be given priority in management decisions. However, molecular studies with higher resolution are needed to fully test possible genetic and epigenetic components that could promote the invasion process.

The shear Alfvén continuum with a magnetic island chain in tokamak plasmas

The shear Alfvén continuum spectrum is studied for a tokamak with a single island chain using the ideal magnetohydrodynamics theory. We have taken into account the toroidal geometry and toroidal mode coupling with the island considered as a highly-shaped stellarator. Various new frequency gaps open up inside the island due to its asymmetry both poloidally and toroidally, such as the mirror-induced Alfvén eigenmode (MAE) gap and the helicity-induced Alfvén eigenmode (HAE) gap. We have shown that the MAE gap acts as the continuation of the outside toroidal Alfvén eigenmode (TAE) gap into the island. However, the combined TAE/MAE gap is getting narrower as the island grows, leaving only half of its original width with a moderate island size as much as 3.2% of the minor radius. In addition, the two-dimensional eigenfunction of the continuum mode on the lower tip of the MAE gap now has highly localised structures around the island’s long axis, contrary to the usual oscillatory global solutions found with no or a low level of toroidal asymmetry—an indication of the continuous spectrum becoming discrete and dense. These results have implications for the frequency, mode structure and continuum damping of global TAEs residing in the gap.

Staphylococcus coagulans possesses many virulence factors of Staph. aureus and Staph. pseudintermedius.

To understand the Staphylococcus coagulans prevalence in causing skin infections in dogs and detection of various virulence genes in Staph. coagulans isolates. Staph. coagulans was isolated from pus swabs collected from dogs with skin infection and identified by detecting thermonuclease, coagulase, and urease genes. The presence of methicillin-resistant gene (mecA) was performed by PCR. Antimicrobial susceptibility test was carried out by disc diffusion method. In total, 38 Staph. coagulans clinical isolates and 42 Staph. coagulans genomes available in NCBI database were screened for 19 virulence genes by PCR and in silico prediction, respectively. A prevalence of 13.8% (38/275) of Staph. coagulans dog skin infection was observed and 15.8% (6/38) of Staph. coagulans isolates carried mecA gene. Many Staph. coagulans isolates were susceptible to all tested antimicrobials. Twenty nine per cent isolates were resistant to ciprofloxacin. Genes encoding leukotoxins, DNase, exfoliative toxin, superantigen-like exotoxin, immunoglobulin-binding proteins, fibrinogen-binding proteins, autolysin, and rod shape-determining protein were detected in almost all the Staph. coagulans clinical isolates and genomes from NCBI database, whereas anti-adhesin plasma-sensitive protein genes were present in relatively lesser number of Staph. coagulans clinical isolates and genomes from NCBI database. Staph. coagulans possesses many virulence factors that are present in other coagulase-positive staphylococci, such as Staph. aureus and Staph. pseudintermedius. The presence of two bi-component leukotoxin genes in tandem with other virulence factor genes in a single pathogenic island in the Staph. coagulans genomes explained their eminence in the virulence of Staph. coagulans causing infections. Staph. coagulans was classified as a separate species in the year 2020 and primarily causes skin infections in dogs. Identification of this species is not included in any of the automated bacterial identification systems. Hence, many veterinary laboratories do not have a strategy to identify this bacterium. This study will help in the identification of Staph. coagulans in veterinary laboratories by PCR apart from detecting various virulence factors present in this pathogen. The existence of many virulence factors and prevalence in different animals in varied geographical locations suggest that Staph. coagulans is an important coagulase-positive staphylococcal pathogen in animals.

Island carrying capacity for three development types: ecological resource, agricultural production, and urban construction

The evaluation of island carrying capacity is the premise for conducting the island spatial planning and can contributes to guiding island ecological conservation and socioeconomic developments. In this study, the island carrying capacities were evaluated for the three major development types, namely, ecological resource, agricultural production, and urban construction, based on the quantity and quality. The occupancy and vacancy rates of island carrying capacity were measured in different scenarios. Miaodao Archipelago and Dongtou Archipelago in China were selected as the study area to demonstrate the evaluation. The former is constituted all by spatially isolated rocky islands, while the latter is featured by the coexistence of the sandy and rocky islands and the connection with the mainland by bridges. The results indicated the high variances of occupancy and vacancy rates of island carrying capacity at multiple spatial scales. Across the two archipelagos, climate conditions, island composition, and spatial connections with the mainland controlled the spatial variance at this scale. For different types of islands, the sandy island presented distinctly higher occupancy and vacancy rates for agricultural production than the rocky islands. At the single island scale within the same archipelago, the developments of agricultural production and urban construction distinctly increased with the increase in the island area. The dependency of island constructions on the external world in Dongtou Archipelago was higher than that in Miaodao Archipelago. Meanwhile, the difference in traffic conditions between the two archipelagos did not distinctly influence the food dependency on the external world. Then, practical suggestions in terms of quantity control and quality promotion were proposed to improve the island carrying capacity.