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1.
Sensors (Basel) ; 22(14)2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35891101

RESUMO

Lane detection plays an essential role in autonomous driving. Using LiDAR data instead of RGB images makes lane detection a simple straight line, and curve fitting problem works for realtime applications even under poor weather or lighting conditions. Handling scatter distributed noisy data is a crucial step to reduce lane detection error from LiDAR data. Classic Hough Transform (HT) only allows points in a straight line to vote on the corresponding parameters, which is not suitable for data in scatter form. In this paper, a Scatter Hough algorithm is proposed for better lane detection on scatter data. Two additional operations, ρ neighbor voting and ρ neighbor vote-reduction, are introduced to HT to make points in the same curve vote and consider their neighbors' voting result as well. The evaluation of the proposed method shows that this method can adaptively fit both straight lines and curves with high accuracy, compared with benchmark and state-of-the-art methods.

2.
Insects ; 13(3)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35323546

RESUMO

We investigated and described the thoracic structures, jumping mechanism, and promesothoracic interlocking mechanism of the click beetle Campsosternus auratus (Drury) (Elateridae: Dendrometrinae). Two experiments were conducted to reveal the critical muscles and sclerites involved in the jumping mechanism. They showed that M2 and M4 are essential clicking-related muscles. The prosternal process, the prosternal rest of the mesoventrite, the mesoventral cavity, the base of the elytra, and the posterodorsal evagination of the pronotum are critical clicking-related sclerites. The destruction of any of these muscles and sclerites resulted in the loss of normal clicking and jumping ability. The mesonotum was identified as a highly specialized saddle-shaped biological spring that can store elastic energy and release it abruptly. During the jumping process of C. auratus, M2 contracts to establish and latch the clicking system, and M4 contracts to generate energy. The specialized thoracic biological springs (e.g., the prosternum and mesonotum) and elastic cuticles store and abruptly release the colossal energy, which explosively raises the beetle body in a few milliseconds. The specialized trigger muscle for the release of the clicking was not found; our study supports the theory that the triggering of the clicking is due to the building-up of tension (i.e., elastic energy) in the system.

3.
Zookeys ; 993: 47-120, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262675

RESUMO

The Chinese species of Phorocardius Fleutiaux, 1931 have been studied and six species are described as new: P. alterlineatus Ruan & Douglas, sp. nov.; P. flavistriolatus Ruan & Douglas, sp. nov.; P. minutus Ruan & Douglas, sp. nov.; P. rufiposterus Ruan & Douglas, sp. nov.; P. yunnanensis Ruan & Douglas, sp. nov.; and P. zhiweii Ruan, Douglas & Qiu, sp. nov. Lectotypes are designated for Cardiophorus comptus Candèze, 1860, Cardiophorus contemptus Candèze, 1860, Phorocardius magnus Fleutiaux, 1931, and Cardiophorus manuleatus Candèze, 1888. The holotype is identified for Cardiophorus yanagiharae Miwa, 1927. Phorocardius florentini (Fleutiaux, 1895) and P. manuleatus (Candèze, 1888) are newly reported from China; P. comptus (Candèze, 1860) is excluded from the Chinese fauna. A key to the 11 Phorocardius species known from China is given. Phorocardius is newly recorded from deep within the Palearctic Region. The procoxal cavities of P. rufiposterus Ruan & Douglas, sp. nov. are closed, which is different from all other species of Phorocardius. An annotated checklist of the 21 Phorocardius species of the world is provided. Additionally, Phorocardius contemptus (Candèze, 1860), comb. nov. is transferred from Cardiophorus to Phorocardius; four species are transferred from Phorocardius to Displatynychus: Displatynychus bombycinus (Candèze, 1895), comb. nov., Displatynychus pakistanicus (Platia & Ahmed, 2016), comb. nov., Displatynychus sobrinus (Laporte, 1840), comb. nov., and Displatynychus tibialis (Platia & Ahmed, 2016), comb. nov.

4.
Zookeys ; 857: 85-104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303806

RESUMO

Five species of Scutellathous Kishii, 1955 are recognized from China, of which three are new. Scutellathoushabenularis sp. nov., S.nanlingensis sp. nov., and S.quadrata sp. nov. are described and illustrated. A key to species from China, a checklist, and a distribution map are provided. The relationships and comparisons among genera Athous Eschscholtz, 1829, Ohirathous Han & Park, 2012, Parathous Fleutiaux, 1918, and Scutellathous Kishii, 1955 are discussed.

5.
Zookeys ; 852: 111-124, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31210746

RESUMO

Sternocampsuscoriaceus, sp. nov. is described and illustrated from China. A new combination, Campsosternuscastaneus (Jiang & Wang, 1999) is proposed. A key and a checklist of the known species, together with a distribution map of Chinese Sternocampsus species, are provided.

6.
Zootaxa ; 4403(1): 186-200, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29690252

RESUMO

The flea beetle genus Meishania Chen Wang is revised and five new species-M. cangshanensis sp. nov., M. flavipennis sp. nov., M. fulvotigera sp. nov., and M. sichuanica sp. nov. from China and M. bhutanensis sp. nov. from Bhutan-are described. All species of Meishania are illustrated and a key to species is provided.


Assuntos
Besouros , Distribuição Animal , Estruturas Animais , Animais , Butão , China , Sifonápteros
7.
Zootaxa ; 4526(4): 589-599, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30651508

RESUMO

Dima guizhouensis Ruan, Kundrata Qiu sp. nov. and Dima xiaolongi Ruan, Kundrata Qiu sp. nov. are described from Guizhou and Hunan Provinces in China, respectively. Both species are easily distinguishable from most of their congeners by having a strongly convex pronotum and relatively long elytra with carinate interstria VI. The only superficially similar species is D. tianmuensis Qiu Kundrata in Qiu et al. (2018) from Zhejiang Province. Habitus and main diagnostic characters are figured for both new species, and their systematic placement is discussed. The discovery of these species brings the total number of Dima species in China to 13.


Assuntos
Besouros , Distribuição Animal , Animais , China
8.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(11): 1134-1137, 2017 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-29132457

RESUMO

OBJECTIVE: To investigate the relationship between serum 25-hydroxyvitamin D [25(OH)D] levels at birth and respiratory distress syndrome (RDS) in preterm infants. METHODS: This retrospective study recruited preterm infants with gestational age of below 34 weeks who were born between January 2014 and December 2016. These preterm infants were divided into two groups: RDS (n=72) and control (n=40). Clinical data of the two groups were collected, including gestational age, birth weight, gender, delivery mode, Apgar scores at 1 minute and 5 minutes, incidence of maternal gestational diabetes mellitus, and use of prenatal steroid hormone. Peripheral blood samples were collected and 25(OH)D levels were measured by chemiluminescence immunoassay. The association between serum 25(OH)D levels at birth and RDS was analyzed by multivariate logistic regression. RESULTS: Apgar scores at 1 minute and 5 minutes and serum 25(OH)D levels in the RDS group were significantly lower than those in the control group (P<0.05), while the rates of neonatal asphyxia and vitamin D deficiency were significantly higher than those in the control group (P<0.05). Multivariate logistic regression analysis showed that neonatal asphyxia (OR=2.633, 95%CI: 1.139-6.085) and vitamin D deficiency (OR=4.064, 95%CI: 1.625-10.165) were risk factors for RDS in preterm infants. CONCLUSIONS: Vitamin D deficiency might be associated with increased risk of RDS in preterm infants. Reasonable vitamin D supplementation during pregnancy might reduce the incidence of RDS in preterm infants.


Assuntos
Síndrome do Desconforto Respiratório do Recém-Nascido/sangue , Vitamina D/análogos & derivados , Suplementos Nutricionais , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Síndrome do Desconforto Respiratório do Recém-Nascido/etiologia , Vitamina D/sangue , Deficiência de Vitamina D/complicações
9.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(6): 3911-3912, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-25484166

RESUMO

The Postman Butterfly (Heliconius melpomene) is one of the heliconiine butterflies found in the Central and South America. In this study, the complete mitochondrial genome sequence of its subspecies, Heliconius melpomene rosina, is determined for the first time. Results show that this circular genome is 15,327 bp in length, and consists of 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and a putative control region (D-loop). The genome organization, nucleotide composition and codon usage are identical to those reported from other butterfly mitochondrial genomes. The whole nucleotide composition is 39.33% of A, 42.33% of T, 10.88% of C and 7.46% of G, with a relatively lower level of G and an extremely higher AT content of 81.66%. Most of the PCGs initiate with the ATN start codons except for ND1 and COX1 genes, which separately start with TTG and CGA. Totally 13 PCGs terminate with the standard canonical stop codons of TAA/TAG/TGA or an incomplete stop codon of T- -. The mitochondrial genome sequence reported here would be potentially useful for the phylogenetic studies in butterflies.


Assuntos
Borboletas/genética , Genoma Mitocondrial , Animais , Composição de Bases , Borboletas/classificação , Códon de Iniciação , Códon de Terminação , DNA Mitocondrial/química , DNA Mitocondrial/isolamento & purificação , DNA Mitocondrial/metabolismo , Proteínas de Insetos/química , Proteínas de Insetos/genética , Filogenia , RNA Ribossômico/química , RNA Ribossômico/genética , RNA de Transferência/química , RNA de Transferência/genética , Análise de Sequência de DNA
10.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(3): 1728-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25259453

RESUMO

In this study, the complete mitochondrial genome of a fungus-growing termite, Macrotermes natalensis, with the total length of 16,325 bp, is reported for the first time. This mtgenome harbors 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region (D-loop). The total base composition is 44.1% of A, 21.5% of T, 11.5% of G, and 22.9% of C, so the percentage of A and T (65.6%) is much higher than that of G and C. Most of the genes are distributed on H-strand, except for four subunit genes (ND1, ND4, ND4L, ND5) and eight tRNA genes. All protein-coding genes start with an ATN codon, and terminate with the canonical stop codon (TAA/TAG) or a single T (T- -). The complete mitochondrial genome sequence reported here adds a new genetic resource for the genus Macrotermes and might be useful for phylogenetic and systematic analyses within the genus Macrotermes.


Assuntos
Genoma Mitocondrial , Isópteros/genética , Isópteros/microbiologia , Animais , Pareamento de Bases/genética , Sequência de Bases , Genes Mitocondriais , RNA de Transferência/genética
11.
Opt Express ; 21(22): 26780-5, 2013 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-24216899

RESUMO

An imaging technique has been developed to image a color picture hidden behind a 5 mm thick, highly scattering layer with low transmittance of 0.24%. Small vibrations (< 1 µm) were induced in the hidden picture, causing a time-varying speckle pattern on the scattering layer in the front, which is captured by a CCD camera and quantified as speckle contrast difference (SCD). With two lasers at 543 nm and 633 nm, the imaging system raster-scans the front of the scattering layer and the resulting SCD image reveals the color features of the hidden picture.

12.
Opt Express ; 21(17): 20197-209, 2013 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-24105565

RESUMO

The acoustically modulated laser speckle contrast technique has been employed to quantify and classify 25 colors (made up by different percentages of the two base colors cyan and magenta) hidden behind a 5 mm thick opaque layer with 0.24% transmittance. The main components included two He-Ne lasers (543 and 633 nm), a consumer grade digital camera (Nikon 1 J1), focusing optics and a loudspeaker. The camera captured the laser speckle patterns with the sound on and off, respectively, from which the speckle contrast differences were calculated and used in a nearest neighbor classification algorithm. The classification accuracy was between 55% and 88% depending on the underlying reflectance of all the colors to be classified.

13.
Opt Lett ; 37(19): 4092-4, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23027289

RESUMO

We demonstrate a technique to measure the reflectance of colored objects, including blue, green, and yellow, hidden behind an opaque slab based on acoustically modulated laser speckle. One colored paper at a time was placed behind a 1 cm thick opaque slab with an air gap of 5 mm. Small periodic movements (nanometer scale) at 200 Hz were induced in the colored paper. A coherent red He-Ne laser illuminated the front of the slab, producing acoustically modulated speckle patterns, which were captured by a CCD camera. The magnitude of the time-varying speckle intensity is indicative of the hidden colored paper's reflectance.


Assuntos
Lasers , Fenômenos Ópticos , Cor , Papel
14.
Appl Opt ; 49(3): 497-504, 2010 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-20090817

RESUMO

We report a differential fluorescence speckle confocal microscope that acquires an image in a fraction of a second by exploiting the very high frame rate of modern digital micromirror devices (DMDs). The DMD projects a sequence of predefined binary speckle patterns to the sample and modulates the intensity of the returning fluorescent light simultaneously. The fluorescent light reflecting from the DMD's "on" and "off" pixels is modulated by correlated speckle and anticorrelated speckle, respectively, to form two images on two CCD cameras in parallel. The sum of the two images recovers a widefield image, but their difference gives a near-confocal image in real time. Experimental results for both low and high numerical apertures are shown.

15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(20-21): 1901-6, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19501027

RESUMO

Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) analysis was used to study volatile and semi-volatile compounds emitted by the Eupatorium odoratum (E. odoratum) extract. Variables of HS-SPME such as the type of SPME fiber, extraction time and temperature, incubation time, desorption time and temperature have been optimized. Optimized conditions were obtained by the use of divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber, 5 min/20 min incubation/extraction time at 65 degrees C, 5 min desorption time at 260 degrees C. Using three different polar chromatographic columns to get retention index and mass spectrometry data, 99 volatile and semi-volatile compounds were tentatively identified in the E. odoratum extract. This study has identified the promising source of E. odoratum oviposition repellent.


Assuntos
Chromolaena/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Repelentes de Insetos/análise , Extratos Vegetais/análise , Microextração em Fase Sólida/métodos , Repelentes de Insetos/química , Repelentes de Insetos/farmacologia , Oviposição/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Volatilização
16.
Anal Chem ; 79(23): 8974-8, 2007 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17956148

RESUMO

Disposable sensors based on the degradation of thin films as a result of an enzymatic reaction have been developed into efficient enzyme detectors. Film degradation has traditionally been monitored using surface plasmon resonance (SPR), quartz crystal microbalance (QCM), or classical ac impedance measurements. The enzyme detection principle has now been integrated with an array technology derived from a recently developed impedance imaging technique, scanning photoinduced impedance microscopy (SPIM). SPIM is based on photocurrent measurements at field-effect structures. The material under investigation is commonly deposited onto a semiconductor-insulator substrate. In this work, field-effect capacitors were replaced by hydrogenated amorphous silicon (a-Si:H) n-i-p photodiode structures, which have recently been shown to be suitable for SPIM measurements with good lateral resolution. To demonstrate the feasibility of SPIM for the characterization of biosensor arrays, polymer dots of the inert polymer cellulose acetate and an alpha-chymotrypsin-sensitive poly(ester amide) were deposited onto a-Si:H n-i-p/SiO2 structures and their enzymatic degradation was monitored using a laser scanning setup.


Assuntos
Técnicas Biossensoriais , Microscopia/métodos , Polímeros/química , Reprodutibilidade dos Testes , Ressonância de Plasmônio de Superfície
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