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1.
Sci Rep ; 14(1): 13770, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38877208

ABSTRACT

Indoor inspection robots operating in occupied buildings need to minimize disturbance to occupants and access high areas of a room and cramped spaces obstructed by obstacles for higher inspection coverage. However, existing indoor inspection robots are still unable to meet these requirements. This paper aims to explore the feasibility of applying wall-climbing robots to address these requirements. To this end, we propose a small-sized wall-climbing robot prototype that can move on common indoor surfaces. We extend the proposed prototype to support thermographic inspection by integrating thermal imaging technology into it. Experiment results show that the proposed robot prototype can reach more wall and floor areas for inspection than previously developed indoor inspection robots. It has also been demonstrated that the reduced size and the wall-climbing ability allow the robot to largely avoid human activity areas, thereby reducing disturbance to occupants. This study represents the first attempt to introduce wall-climbing robots into the indoor inspection domain and provides the initial validation of their advantages over existing indoor inspection robots regarding improving inspection coverage and minimizing disturbance to occupants. The findings in this study can provide valuable insights for the future design, selection and application of robotic systems for indoor inspection tasks.

2.
Sensors (Basel) ; 22(6)2022 Mar 14.
Article in English | MEDLINE | ID: mdl-35336415

ABSTRACT

Due to the significant advancement of Natural Language Processing and Computer Vision-based models, Visual Question Answering (VQA) systems are becoming more intelligent and advanced. However, they are still error-prone when dealing with relatively complex questions. Therefore, it is important to understand the behaviour of the VQA models before adopting their results. In this paper, we introduce an interpretability approach for VQA models by generating counterfactual images. Specifically, the generated image is supposed to have the minimal possible change to the original image and leads the VQA model to give a different answer. In addition, our approach ensures that the generated image is realistic. Since quantitative metrics cannot be employed to evaluate the interpretability of the model, we carried out a user study to assess different aspects of our approach. In addition to interpreting the result of VQA models on single images, the obtained results and the discussion provides an extensive explanation of VQA models' behaviour.


Subject(s)
Natural Language Processing
3.
Zootaxa ; 4949(2): zootaxa.4949.2.3, 2021 Mar 25.
Article in English | MEDLINE | ID: mdl-33903343

ABSTRACT

The integrated results of maximum likelihood (ML) and Bayesian inference (BI) analyses, principal component analyses (PCA), and a multiple factor analysis (MFA) recover a new, widely allopatric species of the Cyrtodactylus intermedius species group. Cyrtodactylus kulenensis sp. nov is endemic to the Phnom Kulen sandstone massif of the Phnom Kulen National Park, Siem Reap Province, in the lowlands of northwestern Cambodia. A phylogenetic analysis from a short read (275 base pairs) of the mitochondrial gene NADH dehydrogenase subunit 2 (ND2) from C. kulenensis sp. nov. was aligned with 1449 base pairs from all other species in the intermedius group.  The analysis recovered C. kulenensis sp. nov. as the sister species to a lineage composed of populations from the widely separated hilly regions of Sa Keao and Sakaerat in eastern Thailand. Multivariate (PCA, DAPC, and MFA) and univariate analyses (ANOVA) using combinations of meristic (scale counts), mensural (morphometric), and categorical (color pattern and morphology) characters from 52 specimens encompassing all species of the intermedius group clearly demonstrate C. kulenensis sp. nov. is significantly different and discretely diagnosable from all other species in the intermedius group. This new discovery further highlights the herpetological diversity and high levels of range-restricted endemism in basin-habitat-island landscapes throughout Indochina and the continued need for field work in the landscapes that remain unsurveyed.


Subject(s)
Lizards , Animals , Bayes Theorem , Cambodia , Ecosystem , Factor Analysis, Statistical , Lizards/classification , Lizards/genetics , Lizards/physiology , Phylogeny , Principal Component Analysis
4.
Zool Res ; 40(5): 358-393, 2019 Sep 18.
Article in English | MEDLINE | ID: mdl-31502426

ABSTRACT

We provide an integrative taxonomic analysis of the Lipinia vittigera species complex from mainland Southeast Asia. Based on examination of external morphology, color pattern, and 681 base pairs of the cytochrome oxidase subunit I (COI) mitochondrial gene, we demonstrate the presence of four morphologically distinct lineages of Lipinia in Vietnam, Cambodia, Thailand, and Malaysia, showing a sequence divergence ranging 15.5%-20.4%. All discovered lineages are discretely diagnosable from one another by a combination of scalation traits and color patterns. A review of the published distribution data and a re-examination of available type material revealed the following results:(1) distribution of L. vittigera (Boulenger, 1894) sensu stricto is restricted to Sundaland and the Thai-Malay Peninsula south of the Isthmus of Kra; (2) L. microcercus (Boettger, 1901) stat. nov. is elevated to full species rank; the species has a wide distribution from central and southern Vietnam across Cambodia to eastern Thailand; we regard Lygosoma vittigerum kronfanum Smith, 1922 and Leiolopisma pranensis Cochran, 1930 as its junior synonyms; (3) Lipinia trivittata sp. nov. occurs in hilly areas of southern Vietnam, Cambodia, and eastern Thailand; and (4) Lipinia vassilievi sp. nov. is currently known only from a narrow area along the Vietnamese-Cambodian border in the foothills of the central Annamite Mountain Range. We further provide an identification key for Lipinia occurring in mainland Southeast Asia.


Subject(s)
Lizards/genetics , Lizards/physiology , Pigmentation , Animal Distribution , Animals , Indochina , Species Specificity
5.
PLoS One ; 11(4): e0153108, 2016.
Article in English | MEDLINE | ID: mdl-27050302

ABSTRACT

Based on an integrative taxonomic approach, we examine the differentiation of Southeast Asian snail-eating turtles using information from 1863 bp of mitochondrial DNA, 12 microsatellite loci, morphology and a correlative species distribution model. Our analyses reveal three genetically distinct groups with limited mitochondrial introgression in one group. All three groups exhibit distinct nuclear gene pools and distinct morphology. Two of these groups correspond to the previously recognized species Malayemys macrocephala (Chao Phraya Basin) and M. subtrijuga (Lower Mekong Basin). The third and genetically most divergent group from the Khorat Basin represents a previously unrecognized species, which is described herein. Although Malayemys are extensively traded and used for religious release, only few studied turtles appear to be translocated by humans. Historic fluctuations in potential distributions were assessed using species distribution models (SDMs). The Last Glacial Maximum (LGM) projection of the predictive SDMs suggests two distinct glacial distribution ranges, implying that the divergence of M. macrocephala and M. subtrijuga occurred in allopatry and was triggered by Pleistocene climate fluctuations. Only the projection derived from the global circulation model MIROC reveals a distinct third glacial distribution range for the newly discovered Malayemys species.


Subject(s)
DNA, Mitochondrial/genetics , Turtles/classification , Animals , Cambodia , Phylogeny , Turtles/genetics
6.
Zootaxa ; (3814): 68-80, 2014 Jun 06.
Article in English | MEDLINE | ID: mdl-24943413

ABSTRACT

A new species of the genus Lycodon Fitzinger, 1826 is described from the Cardamom Mountains of southwest Cambodia. Lycodon zoosvictoriae distinctly differs from all other species of Lycodon in Southeast Asia by a combination of its morphometric characters and unique coloration. The new species has 17 dorsal scales at midbody; 2+2 temporals; 8 supralabials; 10 infralabials; loreal separated from internasal and orbit; 213 ventrals; 85 subcaudals; pale tan brown ground color; irregular dark brown blotches on anterior part, 31 transverse blotches on posterior part of body and 26 blotches on tail. Given its submontane type locality, the new species could prove to be endemic to the Cardamom Mountains of southwest Cambodia and probably Southeast Thailand.


Subject(s)
Colubridae/classification , Animal Distribution , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Body Size , Cambodia , Colubridae/anatomy & histology , Colubridae/growth & development , Ecosystem , Female , Male
7.
PLoS One ; 8(10): e72855, 2013.
Article in English | MEDLINE | ID: mdl-24130664

ABSTRACT

The climatic cycles of the Quaternary, during which global mean annual temperatures have regularly changed by 5-10°C, provide a special opportunity for studying the rate, magnitude, and effects of geographic responses to changing climates. During the Quaternary, high- and mid-latitude species were extirpated from regions that were covered by ice or otherwise became unsuitable, persisting in refugial retreats where the environment was compatible with their tolerances. In this study we combine modern geographic range data, phylogeny, Pleistocene paleoclimatic models, and isotopic records of changes in global mean annual temperature, to produce a temporally continuous model of geographic changes in potential habitat for 59 species of North American turtles over the past 320 Ka (three full glacial-interglacial cycles). These paleophylogeographic models indicate the areas where past climates were compatible with the modern ranges of the species and serve as hypotheses for how their geographic ranges would have changed in response to Quaternary climate cycles. We test these hypotheses against physiological, genetic, taxonomic and fossil evidence, and we then use them to measure the effects of Quaternary climate cycles on species distributions. Patterns of range expansion, contraction, and fragmentation in the models are strongly congruent with (i) phylogeographic differentiation; (ii) morphological variation; (iii) physiological tolerances; and (iv) intraspecific genetic variability. Modern species with significant interspecific differentiation have geographic ranges that strongly fluctuated and repeatedly fragmented throughout the Quaternary. Modern species with low genetic diversity have geographic distributions that were highly variable and at times exceedingly small in the past. Our results reveal the potential for paleophylogeographic models to (i) reconstruct past geographic range modifications, (ii) identify geographic processes that result in genetic bottlenecks; and (iii) predict threats due to anthropogenic climate change in the future.


Subject(s)
Phylogeography , Animals , Ecosystem , Genetic Variation , Temperature , Turtles
8.
Zootaxa ; 3599: 246-60, 2013 Jan 07.
Article in English | MEDLINE | ID: mdl-24613873

ABSTRACT

We describe a new species of the agamid genus Calotes Cuvier, 1817 from southern Vietnam, which is most similar to Calotes mystaceus Duméril & Bibron, 1837, but can be distinguished from the latter and its other congeners by genetic and morphological differences. We discuss the current distribution of the new species and its sister species C. mystaceus in Mainland Southeast Asia.


Subject(s)
Lizards/classification , Lizards/genetics , Animals , Electron Transport Complex IV/genetics , Electron Transport Complex IV/metabolism , Female , Lizards/anatomy & histology , Male , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA , Vietnam
9.
J Antimicrob Chemother ; 61(3): 541-7, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18238892

ABSTRACT

OBJECTIVES: Overexpression of efflux pumps such as MDR1 has been identified as an important mechanism contributing to fluconazole resistance in Candida albicans. This phenomenon is frequently observed in fluconazole-resistant strains isolated from AIDS patients treated with various pharmaceuticals. Therefore, we hypothesized that some of these compounds might influence the expression of genes responsible for fluconazole resistance. METHODS: We examined a variety of clinically relevant compounds for their in vitro effects on MDR1 expression with a C. albicans reporter strain containing a transcriptional fusion of the MDR1 promoter (MDR1P) with the gfp gene. Activation of the MDR1 promoter and subsequent green fluorescent protein production was determined by fluorescence microscopy and flow cytometry. Additionally, MDR1 transcription was confirmed and quantified by RT-PCR analysis, followed by Mdr1p detection by western blot. Finally, the effect of a selected agent on resistance to fluconazole was tested by chequerboard titration of both substances. RESULTS: Of 15 compounds tested, only rifampicin induced a rapid and dose-dependent increase in MDR1 expression (up to 122-fold induction), whereas structurally related molecules such as rifabutin and rifamycin were not active. Induction of MDR1 expression upon rifampicin exposure was also observed in 10 blood culture isolates. In contrast, rifampicin exposure did not markedly affect the expression of the transporters CDR1 and CDR2. Increased MDR1 expression was accompanied by elevated MICs for fluconazole after exposure of C. albicans to rifampicin, whereas Mdr1p expression was only moderately induced. CONCLUSIONS: Out of the compounds examined, only rifampicin specifically induced MDR1 expression in all C. albicans strains tested. Rifampicin may play a general role in signal transduction or another means of modulation of gene expression in C. albicans.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/biosynthesis , Candida albicans/physiology , Gene Expression Regulation, Fungal/physiology , Rifampin/pharmacology , ATP Binding Cassette Transporter, Subfamily B , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , Candida albicans/drug effects , Drug Resistance, Fungal/drug effects , Drug Resistance, Fungal/physiology , Gene Expression Regulation, Fungal/drug effects , Humans
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