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Author(s):  
Neha Ahuja ◽  
Rajesh Khanna ◽  
Jaswinder Kaur

Abstract In this work, a printed ultra-wideband (UWB) antenna has been proposed exhibiting band notch characteristics. The proposed design covers the entire UWB band except for the 3.5 GHz band providing the band notch for the WiMAX band. This design consists of two-quarter elliptical patches placed symmetrically over the FR4 substrate. The elliptical shape of the patch is responsible for the UWB band achieved. The slot has been created on the optimized patch area to achieve the desired characteristics providing a notch for the WiMAX band. The slot in the patch is so perfectly designed that it gives the patch a perfect shape of butterfly wings. After designing, the proposed antenna was simulated and then fabricated. The fabricated and simulated results are in close agreement with each other which shows, the proposed UWB antenna is good enough for biomedical applications.


2021 ◽  
Vol 27 (5) ◽  
pp. 1146-1151
Author(s):  
Kee-Young Lee ◽  
Min-Kyung Kim ◽  
Jeong-Hee Kim

Recently, the issue of the harmful effects of nail care products has been posed. In case of cuticle remover, information on hazards of chemical substances is limited and product safety reports are also insufficient. This study evaluated the safety of the top three commercially selling cuticle removers that are widely used in nail care: Blue cross, Zero cleanser and Flower vita cuticle cares. To measure the pH level of cuticle remover cosmetics, distilled water and DMEM. The toxic effect of cuticle removers on cultured HaCaT was identified by MTT-assay. The patch test was performed to evaluate the occurrence of erythema on the patch area according to the criteria of ICDRG after applying the cuticle remover cosmetics (as is). Adherence to the cosmetic pH measurement guidelines, it w as confirmed that the blue cross product did not meet the pH standard of the final product of the domestic cosmetic method. When measuring the pH by diluting DMEM with a solvent, Flower vita product maintained a pH close to Neutral 7.0 overall. All three cuticle removers demonstrated dose-dependent cytotoxic on HaCaT cell. The viability of cells treated with 10 μg/mL Blue cross or 10 μg/mL Zero cleanser was presented below 10%. Otherwise, Flower vita treatment at concentrations of 0.5~20 μg up to 20 μg/mL did not affect the viability (above 70%) in the HaCaT. Of the patch test, there was positive in one case (3.3%) at 2 weeks. It was observed that a doubful reaction (-/+) to Flower vita and weak positive reactions (+) to Blue cross, and zero cleanser. Taken together, it was shown that the Flower vita product have the lowest cytotoxicity in HaCaT cells and slight allergic reaction, proving more safer than other tw o products in vivo and in vitro.


2021 ◽  
Vol 13 (19) ◽  
pp. 4001
Author(s):  
Jason V. Lombardi ◽  
Humberto L. Perotto-Baldivieso ◽  
Maksim Sergeyev ◽  
Amanda M. Veals ◽  
Landon Schofield ◽  
...  

Few ecological studies have explored landscape suitability using the gradient concept of landscape structure for wildlife species. Identification of conditions influencing the landscape ecology of endangered species allows for development of more robust recovery strategies. Our objectives were to (i) identify the range of landscape metrics (i.e., mean patch area; patch and edge densities; percent land cover; shape, aggregation, and largest patch indices) associated with woody vegetation used by ocelots (Leopardus pardalis), and (ii) quantify the potential distribution of suitable woody cover for ocelots across southern Texas. We used the gradient concept of landscape structure and the theory of slack combined with GPS telemetry data from 10 ocelots. Spatial distribution of high suitable woody cover is comprised of large patches, with low shape-index values (1.07–2.25), patch (27.21–72.50 patches/100 ha), and edge (0–191.50 m/ha) densities. High suitability landscape structure for ocelots occurs in 45.27% of woody cover in southern Texas. Our study demonstrates a new approach for measuring landscape suitability for ocelots in southern Texas. The range of landscape values identified that there are more large woody patches containing the spatial structure used by ocelots than previously suspected, which will aid in evaluating recovery and road planning efforts.


2021 ◽  
Vol 879 (1) ◽  
pp. 012038
Author(s):  
A R P Murad ◽  
Syartinilia

Abstract Javan Hawk-Eagle (JHE, Nisaetus bartelsi) is an endemic species in Java Island and an important biological indicator of ecosystem health. The government has issued regulations to protect this species and increase the population by 10% from 2015 until 2019. East Java has the largest JHE potential habitat in Java Island based on a previous study using satellite images of 2002. Therefore, the current habitat distribution of JHE’s is essential for getting knowledge about patch dynamics in JHE’s habitat. This study’s objective was to analyze patch dynamics of JHE’s habitat from 2002 until 2015 and validate habitat distribution. Previously predicted probability map (2002) of JHE’s were updated using Landsat 8 satellite images of 2015 and was validated through ground-truth checked. Results showed that the distribution of JHE’s habitat after validation is 28 patches, which is covered 4766.26 km2. The dynamics that occur in the JHE’s patch are patch lost(1 patch), patch area decreased (5 patches), patch area increased (13 patches), new patch (4 patches), and merged patch. After validation, there are six newly identified patches, and one patch area increased. The total area increased by 2156.14 km2 or 82.61% of the total area occupied by JHE’s in 2002. About 39.89% of total habitat patches were located inside the protected area. This study recommends continuing monitoring activities on habitat patches, including potential habitat patches in lowland areas, and proposing conservation activities based on habitat patch dynamics that occurred from 2002 to 2015.


2021 ◽  
Vol 28 (4) ◽  
pp. 312-324
Author(s):  
Alexander Kurniawan Sariyanto Putera ◽  
Dyah Perwitasari-Farajallah ◽  
Yeni Aryati Mulyani ◽  
Stanislav Lhota ◽  
Riki Herliansyah ◽  
...  

Balikpapan Bay is one of the wetlands providing potential foraging habitat for waterbirds in Indonesia. Potential habitat loss due to oil industry expansion, recent waterbird occurrence, and co-occurrence of two closely related species with similar foraging characteristics led to habitat selection. Habitat selection could be affected by food as an intrinsic factor and extrinsic factor, for example, accessibility to the physical and biological components of the habitat. This study aimed to measure the foraging habitat selection, identify significant habitat quality parameters for the habitat selection and predict the foraging habitat selection model. We used one-zero sampling for collecting foraging habitat selection data, corer sampling for prey data, and collecting the abiotic environment, and Generalized Linear Modelling (GLM) to build the model. We identified four species as the migrant Little Egret (Egretta garzetta), Great Egret (Ardea alba), Purple Heron (Ardea purpurea), and Lesser Adjutant (Leptoptilos javanicus). All species, except Purple Heron, selected foraging habitats. A simple mathematic model of foraging habitat selection was significantly affected by two factors: water depth and patch area. A large patch area may provide primary prey abundance for waterbirds, while a low water depth level may give easy access to the prey.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Zhihua Xu

Aiming at the problem of slow convergence in the parallel calculation of patch area landscape art index, a parallel calculation method of patch area landscape art index based on land cover data was proposed. Firstly, patch type area index, patch connectivity index, patch number index, and fragmentation index were selected as patch area landscape art spatial staggered pattern indexes to conduct characteristic analysis and establish a 3D visual reconstruction model with actual colors. Then, the coordinate points of the landscape space staggered pattern are transformed into three-dimensional visual coordinate points to realize the reconstruction of landscape art space staggered pattern in patch area. The aerial landscape image of patch area is preprocessed and input into GPU to build a Gaussian difference pyramid model. The feature points of the patch area in the aerial landscape image are calculated by the parallel computing process, and the patch boundary in the aerial landscape image is determined. The landscape perimeter of the patch area was calculated according to the boundary. The experimental results show that the complete convergence time of the horizontal axis error and the vertical axis error is 2.13 s and 1.81 s, respectively, and the absolute error and relative error of the perimeter measurement are controlled below 0.60 m and 1.00%, respectively.


2021 ◽  
Author(s):  
James D. Karimi ◽  
Jim A. Harris ◽  
Ron Corstanje

Abstract Context Landscape connectivity is assumed to influence ecosystem service (ES) trade-offs and synergies. However, empirical studies of the effect of landscape connectivity on ES trade-offs and synergies are limited, especially in urban areas where the interactions between patterns and processes are complex. Objectives The objectives of this study were to use a Bayesian Belief Network approach to (1) assess whether functional connectivity drives ES trade-offs and synergies in urban areas and (2) assess the influence of connectivity on the supply of ESs. Methods We used circuit theory to model urban bird flow of P. major and C. caeruleus at a 2 m spatial resolution in Bedford, Luton and Milton Keynes, UK, and Bayesian Belief Networks (BBNs) to assess the sensitivity of ES trade-offs and synergies model outputs to landscape and patch structural characteristics (patch area, connectivity and bird species abundance). Results We found that functional connectivity was the most influential variable in determining two of three ES trade-offs and synergies. Patch area and connectivity exerted a strong influence on ES trade-offs and synergies. Low patch area and low to moderately low connectivity were associated with high levels of ES trade-offs and synergies. Conclusions This study demonstrates that landscape connectivity is an influential determinant of ES trade-offs and synergies and supports the conviction that larger and better-connected habitat patches increase ES provision. A BBN approach is proposed as a feasible method of ES trade-off and synergy prediction in complex landscapes. Our findings can prove to be informative for urban ES management.


2021 ◽  
Author(s):  
Xin Lin ◽  
Chungan Li ◽  
Mei Zhou ◽  
Wenhai Liang ◽  
Biao Li

Abstract This study investigated the short-term spatial variability of an mangrove patch, located in the Pearl Bay in Guangxi, China. Unmanned aerial vehicle (UAV) imagery covering the period from March 2015 to October 2017 were used and the following models were developed: two annual ultra-high resolution spatial resolution digital orthophoto maps (DOMs), two digital elevation models (DEMs), two digital surface models (DSMs), two canopy height models (CHMs), and a canopy height difference model (d-CHM). Using these models, the spatial dynamics of the extent and canopy height of the patch were analyzed. The resolution of the DOMs was 0.1 m, with an average geometrical error of 0.17 m and a maximum error of 0.44 m. The resolutions of DEMs, DSMs, CHMs, d-CHM were all 1 m. The average elevation errors of CHM in 2015 and 2017 were 0.002 m and -0.001 m, respectively, with maximum absolute errors of 0.034 m and 0.030 m, respectively. The average elevation error of d-CHM was -0.003 m and the maximum absolute error was 0.036 m, and the data quality were rated as good. From 2015 to 2017, the area of the mangrove patch increased from 8.16 ha to 8.79 ha, with an average annual increase of 3.7%. Specifically, the areas of expansion, shrinkage, and maximum seaward expansion were 6356 m2, 19 m2, and 24 m, respectively. The driving factor for the variability was natural processes. Stand canopy height exhibited a particular trend of decrease from northwest to southeast (horizontal; parallel to the seawall) and from the land to the sea (vertically; perpendicular to the seawall). From 2015 to 2017, 88.2% of the patch area showed increased canopy height, with an average increase of 0.78 m and a maximum increase of 3.2 m. In contrast, 11.8% of the patch area showed decreased canopy height with a maximum decrease of 3.1 m. The main reason for the decrease in canopy height was the death of trees caused by serious insect plagues. On the other hand, the reason for the increase in height could be attributed to the natural growth of mangrove trees, but further studies are required to verify the cause. UAV remote sensing has an incomparable advantage over traditional methods in that it provides extremely detailed and highly accurate information for in-depth study of the spatial evolution of mangrove patches, which would significantly contribute towards the protection and management of mangroves.


2021 ◽  
Author(s):  
James Karimi ◽  
Jim A. Harris ◽  
Ron Concorstanje

Abstract Context Landscape connectivity is assumed to influence ecosystem service (ES) trade-offs and synergies. However, empirical studies of the effect of landscape connectivity on ES trade-offs and synergies are limited, especially in urban areas where the interactions between patterns and processes are complex.Objectives The objectives of this study were to use a Bayesian Belief Network approach to (1) assess whether functional connectivity drives ES trade-offs and synergies in urban areas and (2) assess the influence of connectivity on the supply of ESs.Methods We used circuit theory to model urban bird flow of P. major and C. caeruleus at a 2 m spatial resolution in Bedford, Luton and Milton Keynes, UK, and Bayesian Belief Networks (BBNs) to assess the sensitivity of ES trade-offs and synergies model outputs to landscape and patch structural characteristics (patch area, connectivity and bird species abundance).Results We found that functional connectivity was the most influential variable in determining two of three ES trade-offs and synergies. Patch area and connectivity exerted a strong influence on ES trade-offs and synergies. Low patch area and low to moderately low connectivity were associated with high levels of ES trade-offs and synergies.Conclusions This study demonstrates that landscape connectivity is an influential determinant of ES trade-offs and synergies and supports the conviction that larger and better-connected habitat patches increase ES provision. A BBN approach is proposed as a feasible method of ES trade-off and synergy prediction in complex landscapes. Our findings can prove to be informative for urban ES management.


Oryx ◽  
2021 ◽  
pp. 1-8
Author(s):  
Rodrigo Costa-Araújo ◽  
André Luis Regolin ◽  
Felipe Martello ◽  
João Pedro Souza-Alves ◽  
Tomas Hrbek ◽  
...  

Abstract Tropical forest hotspots have a high diversity of species but have lost > 70% of their original vegetation cover and are characterized by a multitude of small and isolated fragments. Paradoxically, conservation actions in these areas are still mainly focused on protection of large tracts of forests, a strategy now infeasible because of the small area of forest remnants. Here we use the Vulnerable black-handed titi monkey Callicebus melanochir as a model to study the effects of habitat loss, fragmentation and degradation on arboreal mammals and to provide insights for science-driven conservation in fragmented landscapes in tropical forest hotspots. We surveyed 38 Atlantic Forest fragments in Bahia State, Brazil and assessed the effects of patch area, quality and visibility, and landscape connectivity on the occurrence of our model species. Patch area was the single best model explaining species occurrence. Nonetheless, patch quality and visibility, and landscape connectivity, positively affect occurrence. In addition to patch area, patch quality, patch visibility and landscape connectivity are useful for predicting the occurrence of arboreal mammals in the fragments of tropical forest hotspots. We encourage the assessment of habitat quality (based on remotely sensed vegetation indices) and habitat visibility (based on digital elevation models) to improve discoverability of arboreal mammal populations and selection of fragments for conservation purposes across fragmented landscapes of tropical forest hotspots. Large remnants of tropical forest hotspots are scarce and therefore we require baseline data to support conservation actions and management in small forest fragments.


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