Pattern Of Patches Research Articles

Hierarchically Structured and Tunable Hydrogel Patches: Design, Characterization, and Application.

Recent studies show the importance of hydrogel geometry for various applications, such as encoding, micromachines, or tissue engineering. However, fabricating hydrogel structures with micrometer-sized features, advanced geometry, and precise control of porosity remains challenging. This work presents hierarchically structured hydrogels, so-called hydrogel patches, with internally deviating regions on a micron-scale. These regions are defined in a one-step, high-throughput fabrication process via stop-flow lithography. Between the specified projection pattern during fabrication, an interconnecting lower crosslinked and more porous hydrogel network forms, resulting in at least two degrees of crosslinking within the patches. A detailed investigation of patch formation is performed for two material systems and pattern variations, revealing basic principles for reliable patch formation. In addition to the two defined crosslinked regions, further regions are implemented in the patches by adapting the pattern accordingly. The variations in pattern geometry impact the mechanical characteristics of the hydrogel patches, which display pattern-dependent compression behavior due to predefined compression points. Cell culture on patches, as one possible application, reveals that the patch pattern determines the cell area of L929 mouse fibroblasts. These results introduce hierarchically structured hydrogel patches as a promising and versatile platform system with highcustomizability.

Scale matters: How spatial resolution impacts remote sensing based urban green space mapping?

Urban green spaces (UGS) provide ecological and habitat benefits such as carbon sequestration, oxygen production, humidity increase, noise reduction, and pollution absorption. UGS maps derived from remote sensing images serve as the fundamental data for urban planning and carbon sequestration assessments. However, the spatial resolution of remote sensing image and the pattern of urban structures significantly influence UGS mapping, making it challenging to obtain accurate UGS maps. To investigate the impact of spatial resolution on UGS mapping, this study utilized five different spatial resolution datasets: Gaofen2 (1 m, 4 m), Sentinel2 (10 m), and Landsat8 (15 m, 30 m). Random forest, LightGBM, and support vector machine were employed to map UGS, and the accuracies of UGS maps at different spatial resolutions were compared. Subsequently, the spatial distribution patterns of uncertainties in UGS maps were analyzed from both overall and urban functional zone perspectives. Furthermore, the uncertainty analysis of UGS mapping was conducted considering different landscape patterns in urban functional zones. The results indicate: (1) UGS map varies at different spatial resolution. Higher uncertainties associated with coarser spatial resolutions. Medium and coarse spatial resolution images inadequately capture the fine-grained distribution of urban green spaces. (2) Uncertainty in UGS mapping at different spatial resolutions is generally consistent in spatial distribution. From a functional zoning perspective, the accuracy of green space mapping over non-natural zones is sensitive to spatial resolution. (3) The distribution pattern of UGS patches affects the accuracy of UGS mapping. Uncertainty can be reduced in UGS mapping at medium and coarse spatial resolutions based on UGS landscape pattern indices by multiple linear regression, random forest and LightGBM model. This study comprehensively reveals that uncertainties in mapping UGS from multi-spatial resolution remote sensing images vary across urban functional zones and landscape pattern indices, and it is the first attempt to propose methods for UGS area correction based on landscape pattern indices. The results of this study will facilitate the application of remote sensing data at different spatial resolutions in urban areas.

Edge De-epithelialization for Reducing Pharyngocutaneous Fistula in Patch Free Flap Reconstructions for Salvage Total Laryngectomy Defects: A Case-Control Study.

The leakage of saliva through the deep neck region from a pharyngocutaneous fistula could cause devastating complications, including vascular ruptures leading to mortality. While a partial pharyngoesophageal defect is created after total laryngectomy, a patch pattern of hypopharyngeal reconstruction is required, for which a fasciocutaneous free flap is usually applied. If radiotherapy fails to cure pharyngeal cancer, salvage total laryngectomy (STL) is needed. However, postradiation tissues tend not to heal well, and the incidence of pharyngocutaneous fistula therefore increases. We proposed an edge-epithelialization method to address this problem and conducted a retrospective study for comparison. The inclusion criteria were patients with head and neck cancer who underwent total laryngectomy that immediately required patch free flap reconstruction at a single medical center (January 2012-December 2021). Receipt of presurgical radiotherapy, hospitalization duration, and the presence of postoperative complications were recorded. The included patients were separated into two groups: Group A (edge de-epithelialization not adopted) (n=79) and Group B (edge de-epithelialization adopted) (n=51). Forty-four and twenty-two patients in Groups A and Group B, respectively, received preoperative radiotherapies and simultaneous STL and fasciocutaneous free flap reconstructions. The incidence of pharyngocutaneous fistula was significantly lower in Group B (p=0.0145). This phenomenon was the same for patients who underwent preoperative radiotherapy only (p=0.0470) but not for patients who did not receive preoperative radiotherapy (p=0.2363). Edge de-epithelialization is an effective method for reducing pharyngocutaneous fistula formation in patch free flap reconstructions after STLs.

A novel codominant plumage color pattern of white breast patches in WugangTong geese was controlled by EDNRB2

Two basic plumage color patterns are observed in adult geese: solid grey (G) or colorless white (W). However, a Chinese indigenous breed, the Wugangtong goose (WGT), continues to be subject to selective breeding efforts as it displays segregation of plumage colors, including G, W, and a novel color pattern designated Wb (G with white breast circles). The underlying genetic mechanisms responsible for the Wb phenotype are yet to be determined. The current study employed the population differentiation index (FST) to analyze 90 geese exhibiting diverse plumage colors, identifying the fifth intron of EDNRB2 as a particularly noteworthy region with the highest FST values. Sanger sequencing of the region surrounding the EDNRB2 gene identified a 14-bp insertion within exon 3 as the causal mutation. The heterozygosity of this 14-bp insertion and wild-type alleles was completely associated with the Wb phenotype, thereby substantiating the codominant nature of the G and W phenotypes. An inter-species corroborated this finding cross between the graylag (no 14-bp insertion) and the swan goose (homozygous for the 14-bp insertion) breeds, as hybrids from this cross exhibited the Wb phenotype. Transcriptomes from white breast patches and gray dorsal skins of 4 Wb geese were compared. A significant downregulation of genes involved in melanin synthesis and melanocyte development was observed, including EDRNB2 and MLANA. The downregulation of MLANA indicated that the mutated EDNRB2 resulted in melanocyte loss in specific body regions, as MLANA is a marker gene for melanocytes. The findings were corroborated by melanin staining using the Mansson-Fontana method, which revealed no melanin particles deposited in the white breast patches. In summary, the gray plumage color was codominant to the white color in WGT geese, and plumage color variations were controlled by EDNRB2. The findings of our study offer valuable and practical guidance for the purification of plumage colors among WGT, whether through traditional phenotype selection or molecular breeding methods.

Spatial Modeling of Insect Pollination Services in Fragmented Landscapes.

Pollination mapping and modeling have opened new avenues for comprehending the intricate interactions between pollinators, their habitats, and the plants they pollinate. While the Lonsdorf model has been extensively employed in pollination mapping within previous studies, its conceptualization of bee movement in agricultural landscapes presents notable limitations. Consequently, a gap exists in exploring the effects of forest fragmentation on pollination once these constraints are addressed. In this study, our objective is to model pollination dynamics in fragmented forest landscapes using a modified version of the Lonsdorf model, which operates as a distance-based model. Initially, we generated several simulated agricultural landscapes, incorporating forested and agricultural habitats with varying forest proportions ranging from 10% to 50%, along with a range of fragmentation degrees from low to high. Subsequently, employing the modified Lonsdorf model, we evaluated the nesting suitability and consequent pollination supply capacity across these diverse scenarios. We found that as the degree of forest fragmentation increases, resulting in smaller and more isolated patches with less aggregation, the pollination services within landscapes tend to become enhanced. In conclusion, our research suggests that landscapes exhibiting fragmented forest patch patterns generally display greater nesting suitability due to increased floral resources in their vicinity. These findings highlight the importance of employing varied models for pollination mapping, as modifications to the Lonsdorf model yield distinct outcomes compared to studies using the original version.

Cattle and nurse trees shape subtropical forest–grassland ecotones

Abstract South American subtropical landscapes are dominated by open grasslands and mosaics of forest–grassland formations. Forests are often restricted to riverine margins with sharp forest–grassland ecotones. Understanding the mechanisms maintaining forest–grassland ecotones is important to anticipate the effects of changing climate and disturbance regimes on the extent of these biomes and the ecosystem services they provide. We used a combination of field surveys and long‐term field experiments to explore the mechanisms that explain tree cover expansion at the ecotone of riverine forests and grasslands in central Uruguay, within the South American Campos. We assessed the role of tree seed dispersal and seedling establishment limitations, and experimentally tested for the effects of cattle, nurse tree cover and grasses on the recruitment of forest and grassland tree species at the forest–grassland ecotone. We found that forest expansion depends on the interplay between cattle and nurse trees. Vachellia caven trees colonize the grassland successfully and facilitate the formation of forest patches by enhancing seed accumulation and seedling establishment of forest tree species. Surprisingly, grass cover had mostly positive effects on early seedling survival of forest tree seedlings. However, cattle limits tree seedling growth and survival, especially of forest tree species. This results in a nucleated vegetation pattern of tree patches that ultimately limits forest expansion. Synthesis and applications. Tree cover can potentially expand on the subtropical South American grasslands. Reductions in cattle densities and increases in rainfall levels associated with climate change could facilitate forest expansion in this region.

Genetic algorithm-enabled on-demand co-design of optically transparent metamaterial for multispectral stealth applications.

This paper proposes a genetic algorithm (GA)-enabled co-design method for the development of metamaterials with on-demand microwave reflectivity and infrared (IR) emissivity. First, we proposed a multilayered metamaterial based on metasurface with hexagonal patch and ring patterns. An equivalent circuit model (ECM) was then established to model the microwave reflectivity of the metamaterial. To achieve broadband low microwave reflectivity, a GA based on this ECM was adopted to optimize the structural parameters of the metamaterial. A co-design task was accomplished by setting a judgment condition in the algorithm for low IR emissivity. With the help of GA, a metamaterial with broadband low microwave reflectivity and low IR emissivity was designed. Subsequently, a prototype metamaterial was fabricated by patterning optically transparent indium tin oxide films. The calculated, simulated, and measured results agreed well. The co-designed metamaterial had an IR emissivity of 0.15 within the spectral range of 3-14 µm, -10 dB microwave reflectivity at frequencies of 3.1-32.2 GHz, and transparency in the visible band. The proposed co-design method will benefit the design and application of multispectral stealth metamaterials.

Embedded system controlled switching system for reconfigurable antennas

AbstractA multiband and reconfigurable antenna is the one of the main aspects in the communication system which has an extremely important role. An embedded based solution for the fast operation of a reconfigurable antenna to work in a specific operating frequency band is the solution of future technologies. Embedded based solution increases the speed by avoiding the dependence on manual control of the RF switching elements. In this paper, the proposed embedded system‐controlled switching mechanism operate the reconfigurable antenna in any one of the operating bands by a single command to be send from a remote location. The embedded system receives the command and configure a set of PIN diodes as per the modes. The proposed solution consists an Arduino UNO board as motherboard, SIM900A as GSM module to receive the command from user, biasing circuit to control the operation of PIN diode, PIN diode to reconfigure the patch pattern and a user mobile for sending AT command.The proposed model is successful and tested on proteus software 8.0. The model is also deployed on the newly designed multiple‐input‐multiple‐output antenna where the result shows the successful operation to achieve multiband frequency operation.

Fire refugia patch dynamics differ between prescribed fires and wildfires in longleaf pine savanna

Increasing wildfire activity has spurred an increasing push for the application of prescribed fire to reduce wildfire risk while simultaneously acting as a surrogate for fire’s historical role as a fundamental ecosystem process. However, prescribed fires are often ignited using uniform ignitions to maintain operational control and there are concerns that they may not be able to replicate the landscape heterogeneity, particularly patterns in unburned patches, generated by historical fires. Fire refugia, unburned areas within fire perimeters, play an integral role in determining post-fire recovery and community structure. We assess patterns in fire refugia across 443 large (>200 ha) wildfire and prescribed fire perimeters using remotely sensed fire severity data in longleaf pine (Pinus palustris) savannas of the Florida Panhandle. Contrary to concerns, large prescribed fires had a significantly greater proportion of unburned area than wildfires, driven by larger refugia patch sizes. Drier conditions promoted smaller and more numerous fire refugia patches. Our study demonstrates differences in wildfires versus prescribed fire outcomes on landscape structure, with implications for future longleaf pine savanna management.

Characteristics and Influencing Factors of Landscape Pattern Gradient Transformation of Small-Scale Agroforestry Patches in Mountain Cities

Small-scale agroforestry patches possess irreplaceable value compared to large-scale patches. In southwestern mountainous cities of China, the complex terrain and urbanization have led to the presence of numerous small, fragmented agroforestry patches around urban areas. These patches serve as crucial habitats for endemic species and provide essential space for wild food sources, thereby contributing to a range of ecosystem services. Consequently, their proper conservation and utilization planning are of paramount importance. This study investigates the transformation characteristics of landscape patterns of mountainous small-scale agroforestry patches and their constituent elements across urban–rural gradients, identifying the driving factors behind these transformations to support conservation and utilization planning. From an urban–rural gradient perspective, four directional transects were selected and divided into uniform sample grids. Using Fragstats 4.3, landscape indices of small-scale agroforestry patches were calculated, analyzing the transformation characteristics of these patches and their elements across different gradients. Spearman correlation coefficients in SPSS were employed to assess the influence of terrain and relevant anthropogenic factors on the transformation of agroforestry patches. The findings reveal the following: (1) Small-scale agroforestry patches and their elements exhibit similar patterns in terms of size, fragmentation, dispersion, and connectivity, showing an “increasing trend in size and connectivity, decreasing fragmentation, and fluctuating dispersion” from urban centers to natural areas, with slight variations in orchard patches. However, patch cohesion and shape complexity display nonlinear differentiated transformation characteristics. (2) Overall, small-scale agroforestry patches are significantly influenced by anthropogenic construction factors, with the landscape pattern of forest patches notably affected by terrain factors. (3) Across urban–rural gradient zones, the landscape patterns of small-scale agroforestry patches in urban centers, suburbs, and rural natural areas are more affected by terrain factors, whereas those in urban construction zones are significantly influenced by anthropogenic construction factors. The findings of this study provide a scientific basis for the conservation and planning of mountainous small-scale agroforestry patches.

Changes in secondary sexual characteristics of female red swamp crayfish (Procambarus clarkii) and relationship to ovarian development: Implications for intensive breeding of seedlings

A rapid selection method of mature Procambarus clarkii females for use in intensive breeding of seedlings is proposed based on evaluation of secondary sexual characteristics and variation patterns in this study. Following regular sampling in ponds, the weight, cephalothorax length, annulus ventralis length, body width, white patch coverage (WC) on the uropod, and uropod content weight-to-weight (WW) ratio of female P. clarkii were found to change significantly during ovarian development. The random forest model identified white patches on the uropod as secondary sexual characteristics of female P. clarkii. In fact, the ovarian maturity status could be determined based on the variable pattern of these white patches (distribution shape, coverage, and density), particularly WC. White patches waxed and waned during ovarian development and oviposition. Specifically, white patches were absent from the uropod of female P. clarkii before the avitellogenic stage; visible on the uropod in the early vitellogenic stage (WC < 30%); WC 30–45% occurred in the midvitellogenic stage; WC > 45% occurred in the late vitellogenic stage; and white patches disappeared from the uropod of female P. clarkii in the post-vitellogenic and resorptive stage. The accuracy of identifying mature female P. clarkii (late vitellogenic stage) based on the white patch pattern was 86.36%. Hence, the observation of white patch changes on the uropod might represent an effective method for rapidly identifying mature female P. clarkii with the potential to improve artificial intensive breeding.

Clonal propagation, scale dependent assembly, and nucleation drives natural regeneration in a restinga sandy coastal plain

AbstractOn the sandy coastal plains, environmental filters that limit seedling establishment and survival create a naturally heterogeneous landscape, formed by vegetation patches inserted in a matrix of bare sandy soil. The succession processes in these ecosystems depend on some pioneer species that facilitate the recruitment and survival of other species. Here, we evaluated the spatial pattern and changes of vegetation patches of restinga (i.e., coastal sandy plain vegetation) over one decade (2011–2021). The research was carried out in Alagoas State, Northeast of Brazil. We considered as patches the vegetation islands inserted in a matrix of bare sandy soil and applied methodologies of photointerpretation. Landscape metrics included patch area, edge, shape, and core area. To test the effect of landscape metrics on species occurrence and species richness per patch, we applied generalized linear models (GLM) with binomial and quasi‐Poisson distributions, respectively. We used the “betapart” package to evaluate the importance of turnover and nestedness as drivers of beta diversity among patches. Our data indicate that a key plant (Myrciaria floribunda), which can propagate by root suckers, initiates a succession process, creating regeneration nuclei, which seem to follow a deterministic succession pattern until the patch reaches 10 m2 in area. In the successional sequence, the patches grow and coalesce with neighboring patches. Species richness of patches presented an unimodal response to patch size. Overall, there is a greater contribution of species turnover to among‐patch beta diversity. However, for patches smaller than 10 m2, beta diversity was mostly driven by nestedness, reflecting a process of species addition to the growing patches. The succession pattern found in the study area should be considered for the formulation of nature‐based restoration models, expected to be more efficient and effective for ecosystems with similar environmental filters.

A polarization insensitive terahertz tri-band graphene metasurface absorber

A graphene-based tri-band perfect metasurface absorber is presented for the far-infrared frequency range. A two-dimensional periodic pattern of graphene patches is created on a thin SiO2 dielectric layer, which is backed by a gold ground plane of sufficient thickness ( t ) ensuring zero transmission of the impinging electromagnetic (EM) wave. An array of graphene elliptical discs is placed around graphene square patches and thin graphene strips are used to connect these elliptical patches to the square patches. In terms of the lowest frequency of absorption, the proposed absorber seems to be a thin one as t∼λmax/13. It is also considered compact because the periodicity of the cells is on the order of λmax/22. The absorption spectrum gives three perfect absorption peaks with absorptivity greater than 99% at 5.76 and 9.06 THz. Further, the absorptivity is better than 96% at 7.86 THz. The performance of the proposed absorber remains invariant with change in polarization of the incident wave. It is revealed that this absorber performs satisfactorily throughout a broad angular range of incidence of about ± 60°.

Experimental Study on Influence of Different Patterns of an Emergent Vegetation Patch on the Flow Field and Scour/Deposition Processes in the Wake Region

AbstractFlume experiments were conducted to comprehend the impact of different patterns of an emergent vegetation patch on the flow field and the scour process in natural rivers. Velocity measurements, flow visualization, and scour tests were undertaken around different vegetation patch patterns, which were simulated inspired by the expansion process of a typical instream vegetation. The patch expansion process was idealized with an initially circular patch of rigid emergent stems becoming elongated due to positive and negative feedbacks. The expansion of the vegetation patch was considered to occur in three stages, in which the density of the patch from the previous stage was increased while the patch was also elongated by connecting at its downstream side with another sparser vegetation patch. These stages were replicated succesively by increasing the density and elongating the patch. In this way, two processes (i.e., elongation and decrease in permeability), which usually have hydrodynamically opposite effects on flow fields, were simulated at the same obstruction. Despite generally elongated obstacles being streamlined bodies, the morphometric analysis obtained by laser scanner revealed that streamlined elongation of permeable patches amplifies global scour and enhances localization of the local scour hole. This situation implies that as the patch expands, in the wake region, the steady‐wake region becomes shorter, turbulence diminishes, lateral shear stress enhances, and deposition cannot occur far from the patch. Consequently, as the patch expands, the hydrodynamic consequences may restrict further patch expansion after a certain length/density.

The relative impacts of vegetation, topography and weather on landscape patterns of burn severity in subtropical forests of southern China

Understanding the landscape patterns of burn severity is vital for managing fire-prone ecosystems. Relatively limited research has been done about fire and burn severity patterns in subtropical forests. Here, we derived the pre-fire forest type data from a global land-cover product at 30 m resolution based on time-series Landsat imageries. Using Landsat 8 OLI remote sensing imagery and field-based composite burn index (CBI), this study spatially mapped the burn severity of 27 forest fires in the subtropical forest ecosystems in southern China from 2017 to 2021. The landscape pattern of patches with different burn severity was quantified using landscape indices. In addition, factors influencing the patterns of burn severity across the landscape were determined using the Geodetector model. Burn severity of patches varied significantly over space. High burn severity was common in forest patches with low fragmentation, low patch density, and regular shape. In contrast, moderate and low burn severity was prevalent in patches with smaller patch size, high patch density, and complex shapes. Extensively burned forest patches were located at higher elevations, while more fragmented patches were located in gently sloping areas. Topographic factors were the most significant factors influencing variances in burn severity across the forest patches, followed by weather conditions. Compared to low elevation areas, vegetation types at the high elevation areas (dominated by Masson pine) are more singular, with higher fuel loads, thus resulting in a more regularly-shaped distribution of highly severe burning patches. A detailed understanding of burn severity patterns and driving factors in a landscape can help develop sustainable forest management and restoration strategies. Practically, fire managers should conduct mechanical fuel treatments or thinning of forests at high-elevation areas to reduce the potential of severe fire behavior and the continuity of fire spread.

Decreased species richness along bare patch gradient in the degradation of Kobresia pasture on the Tibetan Plateau

The Kobresia pasture in the Tibetan Plateau, as the world's largest and most unique pastoral alpine ecosystem, is undergoing severe degradation, visible in the formation of bare patches. Characteristics of bare patches in Kobresia pastures are regarded as indicators of the fragmentation and degradation of the alpine landscapes. Here, we used unmanned aerial vehicles (UAV)-based low-elevation remote sensing to monitor 72 study sites in the eastern Tibetan Plateau for identifying the spatial patterns of bare patches of Kobresia pasture degradation on regional scale. We conducted field surveys of species composition, quantified fragmentation caused by bare patches using four landscape indices (patch area, total edge length, shape index and splitting index, representing the patch area, length of the edge, shape, and dispersion of the bare patches, respectively), then modeled the response of plant species richness and productivity at the scale of 50 × 50 m to the Kobresia pasture fragmentation process. Our results indicated that species richness and biomass production decreased significantly with each increasing bare patch index. The total edge length of bare patches increased the spatial turnover of plant species. Although bare patch area significantly decreased the species richness of plant communities, it led to a decrease in forb richness and an increase in grass richness along the degradation of Kobresia pastures.Bare patch areas, as the most easily accessible and highly accurate parameter by UAV-based low-elevation remote sensing, significantly related to the decrease in species richness and productivity, and mainly explained the changes in functional group composition. For assessing the ecological integrity of grassland functionality (plant species diversity and above-ground productivity), bare patch area can be used as an important indicator of Kobresia pasture degradation.

Fertility islands, keys to the establishment of plant and microbial diversity in a highly alkaline hot desert

The distribution of plant communities in hot desert ecosystems is discontinuous and resembles the pattern of heterogeneous resource patches, known as “fertility islands”. Understanding the key factors that allow plants to establish in these conditions, as well as their associated microbial diversity, is crucial to the comprehension and preservation of these ecosystems. Saudi Arabia in the Arabian Peninsula, is one of the driest regions in the world, with a very low water regime and low soil nutrient contents. The establishment of ecosystems in these arid desert conditions is therefore subject to numerous constraints. Understanding the biotic and abiotic factors linked to the formation of fertility islands, from the perspective of soil composition and its associated microbiome, both in the soil and in the roots of associated plant community, is therefore a fundamental issue for the preservation of these ecosystems. In this study, we analyzed the soil composition between a fertility island and bare soil. The proportions of micro- and macro-elements important for plant nutrition, namely magnesium, phosphorus, potassium and iron were higher in the fertility island. We also observed that soil bacterial and fungal diversity increased in the fertility island. Key taxa such as Rhizobia and Glomeraceae which play important roles in ecosystem functioning were identified in both the fertility island soil and in the roots of the established plant community. These results confirm that plant establishment is linked to soil conditions, in line with the fertility island hypothesis, and that the microbial community in the fertility island differs both in diversity and in composition from that of the bare soil. Fertility islands soils and the roots of established plant community harbor a microbiome potentially crucial to ecosystem functioning, and are of major interest for conservation and agronomy programs.

Separated Fan-Beam Projection with Gaussian Convolution for Invariant and Robust Butterfly Image Retrieval.

Butterfly image retrieval is a challenging issue requiring the feature representation not only to be sensitive to the subtle inter-class difference but also to remain robust to large intra-class variations. Fan-beam projection is a mathematical tool originally applied to computed tomographic (CT) reconstruction of objects. In this paper, we introduce it for the first time into object recognition field. Separated fan-beam projection followed by Gaussian convolutions of different widths are designed to extract multiscale invariant features, patch-projection angles (PPA) and texture-projection angles (TPA), for separately depicting the patch patterns and texture properties of butterfly images. The PPA and TPA are then treated as heterogeneous co-occurrence patterns to be fused by a 2D histograms as final feature representation. We present a comprehensive experimental evaluation including image retrieval at species and subspecies levels, complementarity to deep-learning features, invariance and robustness. All the results consistently show the superior performance of the proposed method over the state-of-the arts.

First Report of Fusarium denticulatum Causing Chlorotic Leaf Distortion of Sweetpotato in China.

Sweetpotato (Ipomoea batatas) is one of the most important crops in China. To gain a clearer picture of the occurrence of diseases on sweetpotato, 50 fields (100 plants/field) were randomly surveyed in prominent sweetpotato growing areas of Lulong county, Hebei Province in the years 2021-2022. Plants showing chlorotic leaf distortion with mildly twisted young leaves and stunted vines were observed frequently. It was similar to the symptoms of chlorotic leaf distortion of sweetpotato (Clark et al. 2013). The incidence of disease with patch pattern ranged from 15% to 30%. Ten symptomatic leaves were excised, surface disinfested with 2% sodium hypochlorite for 1 min, rinsed three times in sterilized ddH2O, and cultured on potato dextrose agar (PDA) at 25°C. Nine fungal isolates were obtained. A pure culture of representative isolate FD10 obtained after serial hyphal tip transfer was examined for morphological and genetic characters. Colonies of isolate FD10 on PDA at 25°C were slow growing (4±0.1mm/day) with aerial, white-to-pink mycelium. Lobed colonies had greyish-orange pigmentation in reverse and conidia aggegated in false heads. Conidiophores were prostrate and short. Phialides were mostly monophialidic but occasionally polyphialidic. Polyphialidic openings often denticulate in a rectangular arrangement. Microconidia were abundant, long, oval to allantoid, mostly none or one septate, and 4.79 to 9.53 × 2.08 to 3.22 μm (n = 20). Macroconidia were fusiform to falcate with a beaked apical cell and a footlike basal cell, 3 to 5 septate, and 25.03 to 52.92 × 2.56 to 4.49 µm. Chlamydospores were absent. All in agreement with the morphology of Fusarium denticulatum (Nirenberg and O'Donnell 1998). Genomic DNA of isolate FD10 was extracted. The EF-1α and β-tubulin genes were amplified and sequenced (O'Donnell and Cigelnik 1997; O'Donnell et al. 1998). The obtained sequences were deposited in GenBank (accession nos. OQ555191 and OQ555192). BLASTn revealed that those sequences showed 99.86% (EF-1α) and 99.93% (β-tubulin) homology with the relative sequences of F. denticulatum type strain CBS407.97 (accession nos. MT011002.1 and MT011060.1), respectively. Furthermore, a neighbor-joining phylogenetic tree based on the EF-1α and β-tubulin sequences revealed that the isolate FD10 clustered with F. denticulatum. Based on morphological characteristics and sequence analysis, the isolate FD10 associated with chlorotic leaf distortion of sweetpotato was identified as F. denticulatum. Pathogenicity tests were performed by immersing ten 25-cm-long vine-tip cuttings of cultivar Jifen 1 origin from tissue culture in a conidial suspension (1 × 106 conidia per ml) of isolate FD10. Vines immersed in sterile distilled water used as a control. All inoculated plants in 25-cm plastic pots were incubated in a climate chamber at 28℃ and 80% RH for two and half months and the control were incubated in a separate climate chamber. Nine inoculated plants developed chlorotic terminals, moderate interveinal chlorosis and slight leaf distortion. No symptoms were observed on the control plants. The pathogen was reisolated from inoculated leaves and matched the morphological and molecular characteristics of the original isolates, thus fulfilling Koch's postulates. To our knowledge, this is the first report of F. denticulatum causing chlorotic leaf distortion of sweetpotato in China. Its identification will promote the management of this disease in China.

Kuala Lumpur Green Space Fragmentation Index Analysis and Green Corridors Suggestion using Geographic Information System

More than half of the world’s population lives in urban areas, and the United Nations has projected that nearly all future global population growth will occur in urban areas. Urbanization has caused rapid industrial, transportation and residential development at the expense of environmental deterioration. Activities involving large-scale land clearances are conducted to satisfy human needs for expansion. The clearances have caused green area fragmentation and patches, especially in the rapidly developing urban areas. This study is aimed at detecting the current coverage of green space in the metropolitan city of Kuala Lumpur (KL), the capital city of Malaysia and monitor its fragmentation using a very high spatial resolution satellite data. Green cover which includes trees, grass, and shrubs of KL was first extracted from the SPOT 6 data using Object Oriented method which can classified the green covers. The fragmented green spaces in KL were analyzed using a range of fragmentation indices namely Number of Patches, Edge Density, Class Area, Total Landscape Area, Mean Patch Size and Mean Shape Index using the Patch Analyst tool embedded in the ArcGIS software version 10.0 to study the patterns of green patches. The connectivity of the green patches was studied and proposed to overcome the fragmentation problems. Kuala Lumpur (KL) was chosen as the case study as it is a rapidly developing city with a significant loss of green space. The urban green spaces were more fragmented as there were more built-up areas. Results of the green cover extraction reveal that the KL city centre had the lowest percentage of green cover (2.09 %) area to the urban area compared to the other five zones (Sentul Manjalara 5.03 %, Wangsa Maju Maluri 6.09 %, Damansara Penchala 11.22 %, Bukit Jalil Seputeh 7.07 % and Bandar Tun Razak Sg Besi 7.42 %). Since KL’s urban growth predominantly consists of compact building blocks, the highest land use was believed to be for commercial purposes. Around 66% of industrial and commercial activities are concentrated in the KL city centre, resulting in a diverse green space structure and a growing gap between patches in the city centre zone. The green patches were then connected to create green corridors in the city centre. Several parameters were involved in the analysis, including area, distance, types of land use (green areas and place of interest for the origin and destination), slopes under 7% value (topology with flat surfaces) and road networks. The origin and destination points were analyzed using the network analysis method in Quantum GIS to produce routes with the shortest path algorithm. Results showed that six routes were suitable for designing green corridors in the KL city centre area connecting green spaces and places of interest. All six routes were analyzed every 400 meters using Google Earth Street View to see the surrounding facilities. The Green Corridor Route 6 was the most appropriate for people, as it included parks and places of interest for city dwellers. The green corridor could then be promoted as a walkable area to minimize carbon emissions in the urban area, reducing the urban heat island phenomenon and increasing green connectivity for a better urban life.