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1.
Plant Dis ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640430

RESUMO

Lycium chinense Mill is a deciduous broad-leaved shrub belonging to the Solanaceae family and, is widely distributed throughout Korea. This plant is native to, or cultivated for various oriental medicinal purposes in, multiple regions of Asia, including Korea, China, and Japan (Lee 1982; Kim et al. 1994). Eleven Puccinia species have been reported to infect Lycium species (Otálora et al. 2018). In May and October 2022, symptoms of rust disease caused by Puccinia sp. were observed on almost all the leaves of about 60 sprawling stems of L. chinense plants on the seashore of Jeju island, Korea (33°14'15.0835″N, 126°30'53.40E). Brownish red (uredinium) or blackish brown (telium) pustules were observed on upper and lower surfaces of infected leaves. These symptoms were observed on about 40 L. chinense plants, barely growing between rocks on the seashore of Ulsan Metropolitan City, and on the about 20 L. chinense plants on a small home garden of Jindo-gun, Korea, in June and October 2023, respectively. Uredinia were amphigenous, individually scattered, but sometimes formed groups of two or three on leaves and sepals, ferruginous, pulverulent, and surrounded by a ruptured epidermis, often developing into blackish telia. Urediniospores were either ellipsoid or ovoid, approximately 29.3-34.9 × 17-24.3 µm, with yellowish walls, 1-2 µm thick. The germ pores were bizonate, and each band contained four pores covered by low papillae. Blackish-brown telia were observed on both leaf surfaces. Teliospores were broadly ellipsoidal, and rounded at the apex and towards the base. They were measured approximately 37.1-53.4 × 25-34.5 µm. The walls were light chestnut-brown and 2-3.7 µm thick, apically up to 5-9 µm thick. The swollen pedicel was persistent, basal, hyaline, smooth, and similar in length to the spores (Fig. 1). These morphological characteristics were similar to those of P. tumidipes, as described by Otálora et al. (2018). The representative specimens were preserved at the Animal and Plant Quarantine Agency Herbarium (PQK220531, -230605, and -231026). The fungal internal transcribed spacer (ITS2) and cytochrome oxidase subunit 3(CO3) regions were amplified from the total DNA of the isolates, using the primer pairs ITS5, ITS4, CO3F1, and CO3R1 for phylogenetic analysis (White et al. 1990; Vialle et al. 2009). PCR products were sequenced (Celemics, Seoul, Korea), and deposited in GenBank (Accession numbers are shown in Fig. 2.). The combined ITS2 and CO3 sequences were grouped with those of other isolates of P. tumidipes in the phylogenetic tree (Fig. 2). In November 2022, three pathogenicity tests were conducted using a urediniospore suspension made with the PQK220531 isolate in sterile distilled water. The suspension was smeared onto the upper surface of healthy L. chinense leaves. The three inoculated plants were kept in the dark at saturated moisture levels for 24 hours and placed in an isolated glasshouse together with the three control plants. After two weeks, uredinia of P. tumidipes were observed on the leaves of the inoculated plants, but not on the control plants. Although no spermogonial or aecial stage has been observed in Korea, our study has proven that P. tumidipes is the causal fungus of rust disease in L. chinense. This result is also the first discovery of the New-World P. tumidipes in Asia, showing this fungus is not limitedly distributed in America and suggesting further surveys be done on its exact geographical distribution.

2.
Plant Dis ; 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616387

RESUMO

Puccinia xanthii Schw. is a microcyclic rust fungus, first found on Xanthium strumarium Lour in North Carolina, the United States. This rust fungus is native to the continental United States, Hawaii, Mexico, and the West Indies (Arthur 1934). It has become notoriously invasive and is now distributed in the Europe (Bulgaria, France, Hungary, Italy, Romania, Spain, and the former Yugoslavia), India, Indonesia, Australia, and South Africa (Parmelee 1969; Alcorn 1976; Wahyuno 2012). In East Asia, the fungus has been reported in Japan (Hiratsuka et al. 1992) and China (Zhao et al. 2014) but not in Korea. It has been reported mainly on the invasive weeds Xanthium and Ambrosia species. In addition, it rarely occurs on sunflowers (Helianthus spp.) in Australia (Alcorn 1976), South Africa (Pretorius et al. 2000), and North America (Gulya and Charlet 2002). In Korea, rust disease symptoms caused by a Puccinia fungus were first found on X. orientale L. at the roadside of Okcheon-gun, Chungcheongbuk-do (36 27'95.428"N 127 66'26.378"E) in October 2021 and were repeatedly observed in the same site in 2022. The similar symptom was additionally found on X. orientale in Yesan-gun, Oct. 2022. The symptoms were brown spots on round chlorotic haloes on the adaxial leaf surface and dark brown pustules on the abaxial leaf surface. Telia were brown to dark brown, round, mostly grouped, 0.28-0.61 mm in diameter, and mainly formed on the abaxial leaf surface but sometimes on the adaxial leaf surface. Teliospores were two-celled, pedicellate, and measured 37.6-110 × 12.4-21.5 µm in size; the wall was yellowish or almost colorless, smooth, 1.2-2.6 µm thick at the sides, and up to 7.4 µm thick at the apex. The morphological characteristics of the teliospores were identical to those of P. xanthii described by Arthur (1934) and Parmelee (1969). Based on phylogenetic analyses (e-Xtra 2) of the internal transcribed spacer (ITS) and partial large subunit (LSU) rDNA extracted from the teliospores, they were identified as P. xanthii. BLAST analysis showed that the sequences had high homologies (over 99.82%) with the reference strains of P. xanthii (EF635903 and KX999896). The representative specimens were preserved at the Animal and Plant Quarantine Agency Herbarium (PQK211005 for Okcheon-gun isolate and PQK220913 for Yesan-gun) and the sequences were deposited in GenBank (OR958716 and OR958692). A pathogenicity test was performed by dropping a suspension of germinating teliospores and basidiospores onto the adaxial leaf surfaces of apparently healthy X. orientale plants in Oct. 2022, using the isolate PQK220913 (OR958692). The three inoculated plants were placed together with three controls treated with only distilled water, in the dark at saturated humidity for 24 hours in an isolated greenhouse. After two weeks, typical rust symptoms were observed in the three infected plants, whereas no symptoms appeared in the control plants (e-Xtra 1). The causal fungus was identified as P. xanthii based on host relationships, successful experimental inoculation, morphological characteristics, and sequence similarity of partial DNA fragments. To our knowledge, this is the first report of P. xanthii on X. orientale in Korea. P. xanthii was additionally confirmed on X. orientale in Gumi-si, Boeun-gun, Seongju-gun, Naju-si, and Gunsan-si in 2023, indicating its wide distribution in Korea. It is expected that P. xanthii could be a candidate as a biological agent for controlling the invasive weed, X. orientale.

5.
Plant Dis ; 2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37246338

RESUMO

Malva sylvestris (Malvaceae), known as common mallow, is native to Europe, western Asia, and northern Africa. It was intentionally introduced to Korea as an ornamental plant in the early 20th century, and has become partly naturalized in several areas including the woods (Jung et al. 2017). Among nine microcylic Puccinia species attacking the Malvaceae plants, three species of P. heterospora, P. malvacearum, and P. modiolae have been reported on M. sylvestris (Classen et al. 2000, Colenso 1885, McKenzie 1998 and Melo et al. 2012). Only P. modiolae has been found on Alcea rosea and M. verticillata, and not M. sylvestris in Korea (Lee et al. 2022; Ryu et al. 2022). In August 2022, rust disease symptoms of a Puccinia fungus were observed on some overgrown seedlings of M. sylvestris, which were neglected in containers after sales at a wholesale nursery (36°50'19.8″N, 128°55'28.7″E) in Bonghwa, Korea. Typical rust spots were observed around 60% (on 111 seedlings of the 186 seedlings of M. sylvestris). The brown spots were produced on round chlorotic haloes on the adaxial leaf surface, and brown to dark brown pustules on the abaxial. Subepidermal spermogonia on the adaxial, were obovoid, and 112.1-160.0 × 88.7-149.3 µm in size. Telia were golden-brown to dark brown, round, mostly grouped, and 0.30-0.72 mm in diameter, and mainly hypophyllus. Fusoid teliospores were two-celled, rarely one- or three-celled, 36.2-92.3 × 10.6-19.3 µm in size, with many anomalies appearing notched at apex; wall was yellowish or almost colorless, smooth, 1.0-2.6 µm thick at the sides, and up to 6.8 µm thick at the apex; pedicel was hyaline, thick wall, persistent, and (39.3-)60.4-154.6(-189.9) µm long. Based on these morphological features together with the results of the phylogenetic analyses (e-Xtra 2) using internal transcribed spacer (ITS) and partial large subunit (LSU) sequences according to the method described by Ryu et al. (2022), the fungus was identified as an autoecious P. modiolae, recently reported on M. verticillate and A. rosea in Korea (Lee et al. 2022; Ryu et al. 2022). A representative sample was deposited in the Animal and Plant Quarantine Agency Herbarium (PQK220818). Pathogenicity tests were done using three host plants: M. sylvestris, M. verticillate and A. rosea. Three to four leaf discs with basidiospore-bearing telia were placed on the upper surfaces of healthy young leaves of the seedlings. Three replicates of each host plant set including an untreated control were tested. The plants were kept in an isolated glass house. At ten to twelve days after inoculation, typical telial spots of P. modiolae were recovered, but not in the control plants, showing all three tested species were highly susceptible (e-Xtra 1). The ITS and LSU sequences obtained from the genomic DNAs of each newly recovered rust spot were consistent with that of the inoculum (accession no. OQ542745). The previous A. rosea isolate (OP369290 by Ryu et al. 2022) also showed the pathogenesis on M. sylvestris and M. verticillata by the same tests, mentioned above (e-Xtra 1). To date, only one collection of P. modiolae on M. sylvestris has been reported in Louisiana, the United States (Aime and Abbasi 2018). The results of this study show that P. modiolae is firstly confirmed as the causal rust fungus of M. sylvestris and the same causal agent of M. verticillate and A. rosea rust disease, recently reported in Korea.

6.
Ind Health ; 61(2): 102-111, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35387946

RESUMO

The rate of industrial accidents in Korea is two to three times higher than those in advanced countries such as Germany. These accidents are mainly concentrated in high-risk industrial areas. Using the ninth wave of the Occupational Safety and Health Company Survey by the Occupational Safety and Health Research Institute (OSHRI), we analyzed the influence of corporate culture on the occurrence of occupational accidents in high-risk industries using negative binomial regression. We found that older workers and foreign workers had a positive effect on the accident rate, while female workers had a negative effect on the accident rate. In addition, it was found that the health and safety management organization also reduced occupational accidents. Corporate culture and workplace environment significantly reduced industrial accidents among workers. This suggests that internal elements of an organization such as corporate culture and working environment can have an impact in reducing the occurrence of industrial accidents.


Assuntos
Acidentes de Trabalho , Saúde Ocupacional , Humanos , Feminino , Acidentes de Trabalho/prevenção & controle , Cultura Organizacional , Estudos Transversais , Indústrias , Gestão da Segurança
7.
Virus Genes ; 59(1): 158-162, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36208404

RESUMO

We identified a tentative novel positive-strand RNA virus from Rudbeckia sp., namely, Rudbeckia citrivirus A (RuCVA). The complete genome sequence of the novel virus was 8821 nucleotides in length, excluding the poly(A) tail. It has three open reading frames (ORFs): a putative polyprotein, a movement protein, and a coat protein. Phylogenetic analysis showed that the virus was more closely related to Citrus leaf blotch virus isolates and unassigned citriviruses. The sequence identity of the virus with other citriviruses was lower than 56.9% at the complete nucleotide sequence level. For each ORF, the sequence identity was lower than 64.2% at the nucleotide level and 67.8% at the amino acid level. These results satisfied the species demarcation criteria for Betaflexiviridae. Therefore, we suggest that RuCVA is a novel member of the genus Citrivirus.


Assuntos
Flexiviridae , Rudbeckia , Filogenia , Rudbeckia/genética , Genoma Viral , Fases de Leitura Aberta , RNA Viral/genética
8.
Plant Dis ; 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36399006

RESUMO

Alcea rosea, in the family Malvaceae, is a biennial plant native to China and is grown typically for gardening in Korea (Lee 2003). Seven microcyclic Puccinia species have been reported on A. rosea: P. heterogenea, P. heterospora, P. lobata, P. malvacearum, P. platyspora, P. sherardiana, and P. modiolae (Demers et al. 2015; Aime and Abbasi 2018). In early May 2022, characteristic symptoms of rust were observed on four of ten seedlings of A. rosea purchased at a wholesale nursery (36°50'19.8″N, 128°55'28.7″E) in Bonghwa, Korea. Rust spots were present on almost 90% of the 1,000 seedlings of A. rosea in that nursery during our survey in late May. Through a distribution survey from June to July 2022, similar symptomatic leaves were additionally collected from the leaves of A. rosea grown in gardens at five sites in Gimcheon (two sites), Gumi (one), Seongju (one), and Busan (one). Spots were yellow-orange the center surrounded by chlorotic haloes on the adaxial leaf surface, and reddish-brown or dark brown pustules on the abaxial leaf surface. Over time, the spots enlarged and coalesced, causing the decay of large sections of the leaves, and heavily infected leaves fell early. Spermogonia, produced at the center of the chlorotic spot on the adaxial leaf surface, were subepidermal, obovoid, and 113.2-164.5 × 97.6-153.3 µm in size. Telia were reddish-brown to dark brown, round, mostly grouped, 0.28-0.61 mm in diameter, and mainly formed on the abaxial leaf surface but sometimes on the adaxial leaf surface also. Teliospores were two-celled, but rarely one- or three-celled, and were fusoid and 37. 6-110 × 12.4-21.5 µm in size; the wall was yellowish or almost colorless, smooth, 1.2-2.6 µm thick at the sides, and up to 7.4 µm thick at the apex. The morphological characteristics were similar to those of P. modiolae, although the teliospores in our study were longer than those observed by Aime and Abbasi (2018). For phylogenetic analysis, genomic DNA was extracted from the teliospores of each regional specimen. Partial 18S, internal transcribed spacer (ITS), and partial 28S sequences were amplified using primers NS1, ITS4, ITS5, and LR11. The PCR products were sequenced (Celemics, Seoul, Korea) and deposited in GenBank. The ITS-partial large subunit (LSU) sequence and 28S sequences had 100% homology with other P. modiolae sequences deposited in GenBank (accession numbers are shown in Fig. 2). In the phylogenetic trees of the ITS and LSU sequences, the isolates collected in this study were grouped with the reference sequences of P. modiolae, including the Korean isolate (ON631218) recently reported on Malva verticillata by Lee et al. (2022). For the pathogenicity test, the teliospores with germinating basidiospores were suspended in sterile distilled water and smeared on the upper surface of asymptomatic A. rosea leaves in August. The inoculated plants were sprayed with distilled water and kept in the dark with saturated moisture for 24 h in an isolated glass house of the Animal & Plant Quarantine Agent. After 2 weeks, typical rust spots and telia of P. modiolae were observed on the leaves of the inoculated plants, but not in the control plants, which were only sprayed with distilled, sterilized water and otherwise treated similarly to the inoculated plants. The results of this study show that the casual fungus is P. modiolae, which has been commonly found in A. rosea in Korea. To the best of our knowledge, this is the first report of P. modiolae in A. rosea in Korea.

9.
Sci Rep ; 12(1): 17808, 2022 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-36280678

RESUMO

In this study, we investigated a convolutional neural network (CNN)-based framework for the estimation of the best-corrected visual acuity (BCVA) from fundus images. First, we collected 53,318 fundus photographs from the Gyeongsang National University Changwon Hospital, where each fundus photograph is categorized into 11 levels by retrospective medical chart review. Then, we designed 4 BCVA estimation schemes using transfer learning with pre-trained ResNet-18 and EfficientNet-B0 models where both regression and classification-based prediction are taken into account. According to the results of the study, the predicted BCVA by CNN-based schemes is close to the actual value such that 94.37% of prediction accuracy can be achieved when 3 levels of difference can be tolerated during prediction. The mean squared error and [Formula: see text] score were measured as 0.028 and 0.654, respectively. These results indicate that the BCVA can be predicted accurately for extreme cases, i.e., the level of BCVA is close to either 0.0 or 1.0. Moreover, using the Guided Grad-CAM, we confirmed that the macula and the blood vessel surrounding the macula are mainly utilized in the prediction of BCVA, which validates the rationality of the CNN-based BCVA estimation schemes since the same area is also exploited during the retrospective medical chart review. Finally, we applied the t-distributed stochastic neighbor embedding to examine the characteristics of CNN-based BCVA estimation schemes. The developed BCVA estimation schemes can be employed to obtain the objective measurement of BVCA as well as the medical screening of people with poor access to medical care through smartphone-based fundus imaging.


Assuntos
Macula Lutea , Redes Neurais de Computação , Humanos , Estudos Retrospectivos , Fundo de Olho , Acuidade Visual
10.
Indian J Dermatol ; 67(2): 204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092232

RESUMO

Background: Pigmentary skin disorders impair the quality of life, leading to the development of therapeutic modalities. However, these treatments should focus more on effectiveness and safety. Aims and Objectives: To evaluate the effect of a temperature-adjustable cryotherapy device on the expression of pigmentation-related biomarkers. Methods and Results: A temperature- and time-adjustable cryotherapy device was employed to improve 200 mJ UVB-induced pigmentation on mice at -5°C (for 5, 10 or 20 s), 0°C (for 5, 10 or 20 s), 5°C (for 5, 10 or 20 s), or 10°C (for 5, 10 or 20 s). Expression of pigmentation-related biomarkers, such as tyrosinase, c-kit, melanocortin 1 receptor and microphthalmia-associated transcription factor before and after treatment with the cryotherapy device was investigated with real-time polymerase chain reaction and immunohistochemistry. Results: Expression of pigmentation-related biomarkers was decreased after the treatment of the temperature-adjustable cryotherapy device. Gene expression of the pigmentation-related biomarkers was decreased under the above conditions with some exception. Protein expression of the pigmentation-related biomarkers showed decreased tendency under the conditions with some exceptions. Conclusion: The temperature-adjustable cryotherapy device used in this study reduced the expression of pigmentation-related biomarkers on mice and may be used to treat patients with skin pigmentation.

11.
Arch Virol ; 167(11): 2381-2385, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35920980

RESUMO

Through high-throughput RNA sequencing, we discovered a putative new cytorhabdovirus in the seeds of Rudbeckia sp., which we have tentatively named "rudbeckia virus 1" (RudV1). Its complete 12,502-nt genomic sequence contains five open reading frames (ORFs): ORF1 (putative nucleocapsid protein, N), ORF2 (putative phosphoprotein, P), ORF3 (putative cell-to-cell movement protein, P3), ORF4 (putative matrix protein, M), and ORF5 (putative RNA-dependent RNA polymerase, L). BLASTp searches showed that ORF1, ORF3, ORF4, and ORF5 of RudV1 are most closely related to the corresponding proteins of Tagetes erecta virus 1 (a putative member of the genus Cytorhabdovirus) with 33.87% (88% query coverage), 55.98% (89% query coverage), 35.33% (94% query coverage), and 57.75% (98% query coverage) sequence identity at the amino acid level, respectively. Phylogenetic analysis and pairwise comparisons indicated that RudV1 is a novel member of the genus Cytorhabdovirus within the family Rhabdoviridae.


Assuntos
Rhabdoviridae , Rudbeckia , Aminoácidos/genética , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas do Nucleocapsídeo/genética , Fases de Leitura Aberta , Fosfoproteínas/genética , Filogenia , RNA Viral/genética , RNA Polimerase Dependente de RNA , Rudbeckia/genética
12.
Microbiol Resour Announc ; 11(8): e0042422, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35916506

RESUMO

We determined the complete genome sequence of the citrus vein enation virus (CVEV) collected from a Korean yuja tree (Citrus junos). The CVEV genome has 5,983 nucleotides, showing 97.3 to 98.6% identity with complete genomic sequences of other CVEV isolates, with the highest similarity being to the isolate PCJ.

14.
Sci Rep ; 12(1): 1444, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35087071

RESUMO

We analyzed fundus images to identify whether convolutional neural networks (CNNs) can discriminate between right and left fundus images. We gathered 98,038 fundus photographs from the Gyeongsang National University Changwon Hospital, South Korea, and augmented these with the Ocular Disease Intelligent Recognition dataset. We created eight combinations of image sets to train CNNs. Class activation mapping was used to identify the discriminative image regions used by the CNNs. CNNs identified right and left fundus images with high accuracy (more than 99.3% in the Gyeongsang National University Changwon Hospital dataset and 91.1% in the Ocular Disease Intelligent Recognition dataset) regardless of whether the images were flipped horizontally. The depth and complexity of the CNN affected the accuracy (DenseNet121: 99.91%, ResNet50: 99.86%, and VGG19: 99.37%). DenseNet121 did not discriminate images composed of only left eyes (55.1%, p = 0.548). Class activation mapping identified the macula as the discriminative region used by the CNNs. Several previous studies used the flipping method to augment data in fundus photographs. However, such photographs are distinct from non-flipped images. This asymmetry could result in undesired bias in machine learning. Therefore, when developing a CNN with fundus photographs, care should be taken when applying data augmentation with flipping.


Assuntos
Aprendizado Profundo , Fundo de Olho , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Conjuntos de Dados como Assunto , Técnicas de Diagnóstico Oftalmológico , Humanos , República da Coreia , Estudos Retrospectivos
15.
Virusdisease ; 32(4): 834-836, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34901331

RESUMO

Raphanus sativus cryptic virus 2 (RsCV-2), an unclassified species belonging to the family Partitiviridae, was identified in cabbage seeds (Brassica rapa subsp. pekinensis) imported from Italy using high-throughput paired-end RNA sequencing. Three contigs derived from RsCV-2 isolate PQ shared nucleotide sequence homologies (approximately 94, 87, and 86%) with dsRNA1, 2, and 3 of RsCV-2, respectively. Phylogenetic analysis and pairwise comparison showed that RsCV-2 isolates were more closely related to deltapartitiviruses. To the best of our knowledge, this is the first report of RsCV-2 on B. rapa subsp. pekinensis in the world. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13337-021-00744-w.

16.
Insects ; 12(10)2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34680620

RESUMO

To infer the introduction sources of the oriental fruit fly, Bactrocera dorsalis, we used a mitochondrial marker to reconstruct the haplotype network and 15 microsatellite loci to reveal genetic structure and relationships between the geographically or temporally different collections from Asia. We performed Approximate Bayesian computations to infer a global origin and a source of the quarantine collections found in Korea. As a result, the 40 populations were divided into three groups, of which genetic similarity is not related to the geographic vicinity. Korean samples had a similar genetic structure to Taiwan and Thailand ones. Our results suggest that the place of origin of the B. dorsalis specimens found in Korea's border quarantine is likely to be Taiwan or Thailand. As the global origin of B. dorsalis, we estimated that Taiwan and Thailand were most likely the global origins of Southeast Asian populations by testing hypothetical scenarios by the approximate Bayesian computation analyses. Our results will allow easier identification of the source region of the forthcoming invasion of quarantined B. dorsalis specimens.

17.
Sensors (Basel) ; 21(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34695982

RESUMO

There are multifarious stationary vehicles in urban driving environments. Autonomous vehicles need to make appropriate overtaking maneuver decisions to navigate through the stationary vehicles. In literature, overtaking maneuver decision problems have been addressed in the perspective of either discretionary lane-change or parked vehicle classification. While the former approaches are prone to generating undesired overtaking maneuvers in urban traffic scenarios, the latter approaches induce deadlock situations behind a stationary vehicle which is not distinctly classified as a parked vehicle. To overcome the limitations, we analyzed the significant decision factors in the traffic scenes and designed a Deep Neural Network (DNN) model to make human-like overtaking maneuver decisions. The significant traffic-related and intention-related decision factors were harmoniously extracted in the traffic scene interpretation process and were utilized as the inputs of the model to generate overtaking maneuver decisions in the same manner with the human driver. The overall validation results convinced that the extracted decision factors contributed to increasing the learning performance of the model, and consequently, the proposed decision-making system enabled the autonomous vehicles to generate more human-like overtaking maneuver decisions in various urban traffic scenarios.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Cognição , Humanos , Intenção , Redes Neurais de Computação
18.
Insects ; 12(6)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200556

RESUMO

Lycorma delicatula (White) suddenly arrived in Korea where it rapidly spread out in the central region of Korea and caused serious damage to grape vineyards. To trace the source region of its invasiveness, population genetic structures were compared between the native region, China, and the introduced regions, Korea and Japan. We examined 762 individuals from 38 different population collections using 15 microsatellite loci. Both principal coordinate and structure analyses displayed that the Chinese populations were separated into three subgroups which were located significantly far apart from each other. Among them, the Shanghai population was located closest to most Korean populations. Based on the genetic relationships and structures, it was revealed that the multiple introductions into Korea occurred at least three times. In addition, the Shanghai population was strongly estimated to be a source of initial invasive populations of Korea. In addition, analysis of the approximate Bayesian computation suggested simultaneous spread from two distant locations early in the invasion by artificial transportation of the host plants bearing egg masses. Our population genetics study can provide a precedent case with regards to identifying spreads by anthropogenic outcomes in other invasive regions.

19.
Sci Rep ; 11(1): 10670, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34021183

RESUMO

Optical coherence tomography (OCT) is a noninvasive method that can quickly and accurately examine the eye at the cellular level. Several studies have used OCT for analysis of anterior chamber cells. However, these studies have several limitations. This study was performed to supplement existing reports of automated analysis of anterior chamber cell images using spectral domain OCT (SD-OCT) and to compare this method with the Standardization of Uveitis Nomenclature (SUN) grading system. We analyzed 2398 anterior segment SD-OCT images from 34 patients using code written in Python. Cell density, size, and eccentricity were measured automatically. Increases in SUN grade were associated with significant cell density increases at all stages (p < 0.001). Significant differences were observed in eccentricity in uveitis, post-surgical inflammation, and vitreous hemorrhage (p < 0.001). Anterior segment SD-OCT is reliable, fast, and accurate means of anterior chamber cell analysis. This method showed a strong correlation with the SUN grade system. Also, eccentricity could be helpful as a supplementary evaluation tool.


Assuntos
Câmara Anterior/citologia , Rastreamento de Células/métodos , Processamento de Imagem Assistida por Computador/métodos , Software , Idoso , Algoritmos , Contagem de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica
20.
Polymers (Basel) ; 13(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670700

RESUMO

Functionalized graphene-polymer nanocomposites have gained significant attention for their enhanced mechanical, thermal, and antibacterial properties, but the requirement of multi-step processes or hazardous reducing agents to functionalize graphene limits their current applications. Here, we present a single-step synthesis of thermally reduced graphene oxide (TrGO) based on shellac, which is a low-cost biopolymer that can be employed to produce poly(vinyl alcohol) (PVA)/TrGO nanocomposites (PVA-TrGO). The concentration of TrGO varied from 0.1 to 2.0 wt.%, and the critical concentration of homogeneous TrGO dispersion was observed to be 1.5 wt.%, below which strong interfacial molecular interactions between the TrGO and the PVA matrix resulted in improved thermal and mechanical properties. At 1.5 wt.% filler loading, the tensile strength and modulus of the PVA-TrGO nanocomposite were increased by 98.7% and 97.4%, respectively, while the storage modulus was increased by 69%. Furthermore, the nanocomposite was 96% more effective in preventing bacterial colonization relative to the neat PVA matrix. The present findings indicate that TrGO can be considered a promising material for potential applications in biomedical devices.

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