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1.
Anal Chem ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976234

RESUMO

Photoelectrochemical (PEC) water splitting is gaining recognition as an effective method for producing green hydrogen. However, the absence of in situ, continuous decoding hydrogen generation tools hampers a detailed understanding of the physics and chemistry involved in hydrogen generation within PEC systems. In this article, we present a quantitative, spatiotemporally resolved optical sensor employing a fiber Bragg grating (FBG) to probe hydrogen formation and temperature characteristics in the PEC system. Demonstrating this principle, we observed hydrogen formation and temperature changes in a novel cappuccino cell using a BiVO4/TiO2 photoanode and a Cu2O/CuO/TiO2 photocathode. Our findings demonstrate that FBG sensors can probe dynamic hydrogen formation at 0.5 s temporal resolution; these sensors are capable of detecting hydrogen concentrations as low as 0.6 mM. We conducted in situ and continuous monitoring of hydrogen and temperature to ascertain various parameters: the rate of hydrogen production at the photocathode surface, the time to reach hydrogen saturation, the distribution of hydrogen and temperature, and the rate of hydrogen transfer in the electrolyte under both external bias and unbiased voltage conditions. These results contribute valuable insights into the design and optimization of PEC water-splitting devices, advancing the in situ comprehensive monitoring of PEC water-splitting processes.

2.
Arch Virol ; 169(5): 97, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619640

RESUMO

The complete genome sequence of a novel badnavirus, tentatively named "fatsia badnavirus 1" (FaBV1, OM540428), was identified in Fatsia japonica. The infected plant displayed virus-like symptoms on leaves, including yellowing and chlorosis. The genome of FaBV1 is 7313 bp in length and similar in size and organization to other members of the genus Badnavirus (family Caulimoviridae), containing four open reading frames (ORFs), three of which are found in all known badnaviruses, and the other of which is only present in some badnaviruses. The virus has the genome characteristics of badnaviruses, including a tRNAMet binding site (5'-TCTGAATTTATAGCGCTA-3') and two cysteine-rich domains (C-X-C-2X-C-4X-H-4X-C and C-2X-C-11X-C-2X-C-4X-C-2X-C). Pairwise sequence comparisons of the RT+RNase H region indicated that FaBV1 shares 61.4-71.2% nucleotide (nt) sequence identity with other known badnaviruses, which is below the threshold (80% nt sequence identity in the RT+RNase H region) used for species demarcation in the genus Badnavirus. Phylogenetic analysis revealed that FaBV1, ivy ringspot-associated virus (IRSaV, MN850490.1), and cacao mild mosaic virus (CMMV, KX276640.1) together form a separate clade within the genus Badnavirus, suggesting that FaBV1 is a new member of the genus Badnavirus in the family Caulimoviridae. To our knowledge, this is the first report of a badnavirus infecting F. japonica.


Assuntos
Araliaceae , Badnavirus , Caulimoviridae , Badnavirus/genética , Filogenia , China , Ribonuclease H
3.
Sensors (Basel) ; 24(12)2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38931593

RESUMO

Copper ion (Cu2+) pollution poses a serious threat to marine ecology and fisheries. However, the complexity of seawater and its interference factors make the online detection of Cu2+ quite challenging. To address this issue, we introduce the concept of the photo-assisted adjustment barrier effect into electrochemical detection, using it as a driving force to generate electrochemical responses. The Schottky barrier demonstrates a remarkable regulatory influence on the electrochemical response under photoexcitation, facilitating the response through Cu2+ adsorption. We developed a 4-MBA-AuNPs/CdS/FTO composite that serves as a sensitive platform for Cu2+ detection, achieving a detection limit of 70 nM. Notably, the photo-assisted adjustment of the barrier effect effectively counters the interference posed by ions in seawater, ensuring accurate detection. Furthermore, the sensor exhibits a promising recovery rate (99.62-104.9%) in real seawater samples, highlighting its practical applications. This innovative approach utilizing the photo-assisted adjustment barrier effect offers a promising path for developing electrochemical sensors that can withstand interference.

4.
Sensors (Basel) ; 24(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38610420

RESUMO

This work proposes a highly sensitive sandwich heterostructure multimode optical fiber microbend sensor for heart rate (HR), respiratory rate (RR), and ballistocardiography (BCG) monitoring, which is fabricated by combining a sandwich heterostructure multimode fiber Mach-Zehnder interferometer (SHMF-MZI) with a microbend deformer. The parameters of the SHMF-MZI sensor and the microbend deformer were analyzed and optimized in detail, and then the new encapsulated method of the wearable device was put forward. The proposed wearable sensor could greatly enhance the response to the HR signal. The performances for HR, RR, and BCG monitoring were as good as those of the medically approved commercial monitors. The sensor has the advantages of high sensitivity, easy fabrication, and good stability, providing the potential for application in the field of daily supervision and health monitoring.

5.
Arch Virol ; 168(10): 245, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37676512

RESUMO

A new positive-sense, single-stranded RNA virus, tentatively named "Valeriana jatamansi tymovirus 1" (VaJV1, OQ730267), was isolated from Valeriana jatamansi Jones displaying symptoms of vein-clearing in Yunnan Province, China. The complete genome of VaJV1 consists of 6,215 nucleotides and contains three open reading frames (ORFs). The genome structure of VaJV1 is typical of members of the genus Tymovirus. BLASTn analysis and multiple sequence alignments showed that the complete genome and coat protein of VaJV1 shared the most sequence similarity (65.5% nucleotides and 50.5% amino acid sequence identity) with an isolate of the tymovirus okra mosaic virus (NC_009532). Phylogenetic analysis confirmed that VaJV1 clustered most closely with other tymoviruses. We propose that Valeriana jatamansi tymovirus 1 represents a new species within the genus Tymovirus.


Assuntos
Tymovirus , Valeriana , China , Filogenia , Nucleotídeos , Análise de Sequência
6.
Arch Virol ; 168(10): 248, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37682357

RESUMO

Fusarium diseases include wilts, blights, rots, and cankers of many horticultural, field, ornamental, and forest crops in both agricultural and natural ecosystems, and they significantly hinder food plant production. Here, we describe a novel mycovirus, tentatively designated as "Fusarium fusarivirus 1" (FuFV1), which was discovered in an isolate of the phytopathogenic fungus Fusarium sp. FuFV1 has a positive-sense single-stranded RNA (+ssRNA) genome of 6,391 nucleotides (nt) containing three open reading frames (ORFs). ORF1 encodes a large polypeptide of 1,501 amino acids (aa) with conserved RNA-dependent RNA polymerase (RdRp) and helicase (Hel) domains. ORF2, overlapping ORF1 by 122 nucleotides, encodes a polypeptide with a conserved Smc domain. The third and smaller ORF (ORF3) encodes a polypeptide with an unknown function. BLASTp analysis of the ORF1-encoded polypeptide revealed that FuFV1 shares the highest aa sequence similarity (68.5% identity, E-value 0.0) with Fusarium poae fusarivirus 1 (FpFV1, genus Alphafusarivirus). Phylogenetic analysis of the RdRp and helicase (Hel) sequences indicated that FuFV1 clustered closely with FpFV1 in a separate branch within the clade containing members of the genus Alphafusarivirus. Based on these results, we propose that FuFV1 should be considered a novel mycovirus belonging to the genus Alphafusarivirus of the family Fusariviridae.


Assuntos
Ecossistema , Fusarium , Fusarium/genética , Filogenia , Aminoácidos , DNA Helicases , Fungos , Nucleotídeos
7.
Arch Virol ; 168(5): 154, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37145182

RESUMO

The complete genome sequence of a putative novel closterovirus, tentatively named "Dregea volubilis closterovirus 1" (DvCV1, GenBank accession no. MZ779122), infecting Dregea volubilis in China was determined using high-throughput sequencing (HTS). The complete genome sequence of DvCV1 consists of 16,165 nucleotides (nt) and contains nine ORFs. The genome structure of DvCV1 is typical of members of the genus Closterovirus. Complete genome sequence analysis showed that DvCV1 shares 41.4-48.4% nucleotide sequence identity with other known closteroviruses. The putative RNA-dependent RNA polymerase (RdRp), heat shock protein 70-like protein (HSP70h), and coat protein (CP) of DvCV1 share 46.80-62.65%, 31.06-51.80%, and 28.34-37.37% amino acid sequence identity, respectively, with the RdRp, HSP70h and CP of other closteroviruses. Phylogenetic analysis based on HSP70h aa sequences placed DvCV1 alongside other members of the genus Closterovirus in the family Closteroviridae. These results suggest that DvCV1 is a new member of the genus Closterovirus. This is the first report of a closterovirus infecting D. volubilis.


Assuntos
Closteroviridae , Closterovirus , Closterovirus/genética , Filogenia , Genoma Viral , RNA Viral/genética , Closteroviridae/genética , Fases de Leitura Aberta , Doenças das Plantas
8.
Arch Virol ; 168(5): 139, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37059886

RESUMO

Through high-throughput sequencing, a novel citlodavirus, tentatively named "Myrica rubra citlodavirus 1" (MRV1, accession no. OP374189), was isolated from the leaves of Myrica rubra in Yunnan exhibiting narrow deformity of leaf tips, shrinkage, and chlorosis along the veins. The complete genome sequence was determined and analyzed using cloning and Sanger sequencing. MRV1 is a single-stranded circular non-enveloped DNA virus with a genome size of 3775 nucleotides and contains six open reading frames (ORFs). The virion-sense genome strand encodes a coat protein (CP, nt 750-1,493, 247 aa), two hypothetical movement proteins (V3, nt 382-666, 94 aa; and V2, nt 461-895, 144 aa), and one movement protein (MP, nt 1,527-2,438, 303 aa). The complementary strand of the genome encodes two replication proteins (RepA, nt 3,712-2,834, 292 aa; Rep, nt 2,867-2,553, 104 aa). The MRV1 genome contains the stem-loop motif 5'-TAATATTAC-3', which is a highly conserved nonanucleotide motif found in the origin of virion-strand replication in geminiviruses. Genome sequence alignment analysis showed that citrus chlorotic dwarf associated virus (CCDaV, accession no. JQ920490) shared the highest nucleotide sequence similarity (66.10% identity) with MRV1. Phylogenetic analysis showed that CCDaV is the closest known relative of MRV1, and that these viruses clustered in a single branch within a clade consisting of citlodaviruses. These results indicate that MRV1 should be regarded as a new species of the genus Citlodavirus in the family Geminiviridae.


Assuntos
Myrica , Filogenia , Genoma Viral , China , Sequenciamento de Nucleotídeos em Larga Escala , Fases de Leitura Aberta , Folhas de Planta , Doenças das Plantas
9.
Plant Dis ; 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37947493

RESUMO

Lily virus X (LVX) is a positive-sense ssRNA virus belonging to the genus Potexvirus in the family Alphaflexiviridae. LVX is known to infect plants of the genera Lilium and Tricyrtis in the family Liliacea. LVX was first reported in an asymptomatic lily (Lilium formosanum) from England (Stone, 1980), but has been shown to infect plants in the Netherlands (Chen et al. 2005), the United States (Jordan et al. 2008) and Japan (Nijo et al. 2018). To date, the complete genomes of two LVX isolates from the Netherlands and Japan have been reported. Paris polyphylla var. yunnanensis, known as Dianchonglou in China, is a perennial plant of the family Melanthiaceae (formerly belonging to the family Trillium). In China, its rhizome is commonly used as an antispasmodic agent for stroke and cancer treatment (Chang et al. 2017). From 2019 to 2022, leaf mottle and shrinkage which are typical symptoms of viral infections were observed on the leaves of P. polyphylla var. yunnanensis plants in Dianchonglou fields in Qujing, Yunnan. Disease incidence ranged from 19% to 45% across 5 fields (90 plants per field) in Qujing. To identify the possible viral pathogen(s) associated with the disease, the mirVanaTM miRNA isolation Kit was used to extract total RNA was from a mixed sample pool of 5 symptomatic leaf samples collected from the 5 fields. RNA sequencing library was constructed using TruSeqTM RNA sample preparation kit. Sequencing on the Illumina HiSeqTM 2500 platform (Illumina, USA) with 125-bp paired-end reads yielded 23,077,786 raw reads. 22,534,100 clean reads were obtained by removing reads of low quality and poly-N using Trimmomatic software (Bolger et al. 2014). By utilizing the paired-end splicing method in Trinity software (Grabherr et al. 2011) the the raw reads were De novo assembled into 184,596 contigs, of which 303 were related to viruses, including Paris mosaic necrosis virus (PMNV), Pear alphapartitivirus (PAPV), Dahlia mosaic virus (DMV), and Lily virus X (LVX). BLASTn analysis revealed that 12 contigs (lengths ranging from 344 nt to 5,981 nt, query cover 6% to 99%) were most similar (57.32% to 91.67% nt identities) to the genome sequences of LVX, suggesting a possible infection of LVX in the plants. To confirm the result, a full-length genomic sequence of LVX was obtained by reverse transcription polymerase chain reaction (RT-PCR) using specific primers designed based on the sequence of the assembled contigs. The PCR products were cloned into pGEM-T vector (Promega Corporation, USA) and sequenced using the Sanger method (Sangon Biotech, Shanghai, China). The obtained full-length genomic sequence of the LVX isolate (LVX-PP, accession number OM100017) was 5,981 nt in length. BLASTp analysis demonstrated that the putative Rep and CP of LVX-PP shared 76.27% to 81.05% and 80.81% to 81.82% aa sequence similarities with that of other LVX isolates, respectively. Maximum-likelihood phylogenetic trees inferred from the Rep and CP aa sequences showed that LVX-PP clustered closely with LVX isolates. The leaf samples were further analyzed using a lily virus X (LVX) ELISA kit (DEIAPV181, Creative Diagnostics, U.S.A.). Healthy P. polyphylla var. yunnanensis leaves were taken as a negative control and buffer solution as a blank control. The results showed a positive reaction for all five symptomatic plants (OD = 1.259 ± 0.007) relative to the negative (OD = 0.099) and blank (OD = 0.073) controls. These results indicate that LVX can infect P. polyphylla var. yunnanensis. To our knowledge, this is the first report that LVX has been detected in P. polyphylla var. yunnannensis. This study will serve as an important reference for the study of the host range of LVX. Further studies will be required to determine how LVX spreads between P. polyphylla var. yunnannensis and other host plants.

10.
Sensors (Basel) ; 23(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37299945

RESUMO

Toxoplasma gondii (T. gondii) is a zoonotic parasite that is widely distributed and seriously endangers public health and human health. Therefore, accurate and effective detection of T. gondii is crucial. This study proposes a microfluidic biosensor using a thin-core microfiber (TCMF) coated with molybdenum disulfide (MoS2) for immune detection of T. gondii. The single-mode fiber was fused with the thin-core fiber, and the TCMF was obtained by arc discharging and flame heating. In order to avoid interference and protect the sensing structure, the TCMF was encapsulated in the microfluidic chip. MoS2 and T. gondii antigen were modified on the surface of TCMF for the immune detection of T. gondii. Experimental results showed that the detection range of the proposed biosensor for T. gondii monoclonal antibody solutions was 1 pg/mL to 10 ng/mL with sensitivity of 3.358 nm/log(mg/mL); the detection of limit was calculated to be 87 fg/mL through the Langmuir model; the dissociation constant and the affinity constant were calculated to be about 5.79 × 10-13 M and 1.727 × 1014 M-1, respectively. The specificity and clinical characteristics of the biosensor was explored. The rabies virus, pseudorabies virus, and T. gondii serum were used to confirm the excellent specificity and clinical characteristics of the biosensor, indicating that the proposed biosensor has great application potential in the biomedical field.


Assuntos
Técnicas Biossensoriais , Toxoplasma , Animais , Humanos , Molibdênio/química , Microfluídica , Técnicas Biossensoriais/métodos
11.
Sensors (Basel) ; 23(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36992047

RESUMO

Due to their rapid development and wide application in modern agriculture, robots, mobile terminals, and intelligent devices have become vital technologies and fundamental research topics for the development of intelligent and precision agriculture. Accurate and efficient target detection technology is required for mobile inspection terminals, picking robots, and intelligent sorting equipment in tomato production and management in plant factories. However, due to the limitations of computer power, storage capacity, and the complexity of the plant factory (PF) environment, the precision of small-target detection for tomatoes in real-world applications is inadequate. Therefore, we propose an improved Small MobileNet YOLOv5 (SM-YOLOv5) detection algorithm and model based on YOLOv5 for target detection by tomato-picking robots in plant factories. Firstly, MobileNetV3-Large was used as the backbone network to make the model structure lightweight and improve its running performance. Secondly, a small-target detection layer was added to improve the accuracy of small-target detection for tomatoes. The constructed PF tomato dataset was used for training. Compared with the YOLOv5 baseline model, the mAP of the improved SM-YOLOv5 model was increased by 1.4%, reaching 98.8%. The model size was only 6.33 MB, which was 42.48% that of YOLOv5, and it required only 7.6 GFLOPs, which was half that required by YOLOv5. The experiment showed that the improved SM-YOLOv5 model had a precision of 97.8% and a recall rate of 96.7%. The model is lightweight and has excellent detection performance, and so it can meet the real-time detection requirements of tomato-picking robots in plant factories.


Assuntos
Solanum lycopersicum , Frutas , Agricultura , Algoritmos , Movimento Celular
12.
Sensors (Basel) ; 23(20)2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37896588

RESUMO

This study introduces a new wearable fiber-optic sensor glove. The glove utilizes a flexible material, polydimethylsiloxane (PDMS), and a silicone tube to encapsulate fiber Bragg gratings (FBGs). It is employed to enable the self-perception of hand posture, gesture recognition, and the prediction of grasping objects. The investigation employs the Support Vector Machine (SVM) approach for predicting grasping objects. The proposed fiber-optic sensor glove can concurrently monitor the motion of 14 hand joints comprising 5 metacarpophalangeal joints (MCP), 5 proximal interphalangeal joints (PIP), and 4 distal interphalangeal joints (DIP). To expand the measurement range of the sensors, a sinusoidal layout incorporates the FBG array into the glove. The experimental results indicate that the wearable sensing glove can track finger flexion within a range of 0° to 100°, with a modest minimum measurement error (Error) of 0.176° and a minimum standard deviation (SD) of 0.685°. Notably, the glove accurately detects hand gestures in real-time and even forecasts grasping actions. The fiber-optic smart glove technology proposed herein holds promising potential for industrial applications, including object grasping, 3D displays via virtual reality, and human-computer interaction.


Assuntos
Dedos , Articulações , Humanos , Amplitude de Movimento Articular , Tecnologia de Fibra Óptica , Postura
13.
Opt Express ; 30(22): 40251-40264, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298961

RESUMO

A highly sensitive optical fiber Mach-Zehnder interference curvature sensor based on MMF-GIMMF-MMF, which was made by sandwiching the graded-index multimode fiber (GIMMF) between two pieces of very short stepped-index multimode fibers (SIMMFs) spliced with input-single-mode fiber (SMF) and output-SMF, respectively, was proposed. The core diameter of the SIMMFs and GIMMF was 105 µm and 50 µm, respectively, and cladding diameter of them were both 125 µm. The sensing principle of the MMF-GIMMF- MMF sensors and the influences of structure parameters on the interference spectrum characteristics were theoretically analyzed in detail. Experimental results showed that when the length of the GIMMF was short enough (usually ≤ 10 mm), interference spectrum was induced by the interaction between the core modes and the low-order cladding modes due to the special structure of the designed Mach-Zehnder interferometer. Intensity of the interference valleys was highly sensitive to the applied bending but nearly independent of the surrounding temperature, on the contrary, the dip wavelength showed negligible sensitivity to the applied bending but relatively high temperature sensitivity. Thus, a temperature- independent curvature sensor could be realized by tracing the intensity variation of interference valley. In addition, different interference valley exhibited different intensity-based curvature sensitivity, providing more options for curvature sensing applications. Especially, total length of the sensor could be as short as 3 mm with length of GIMMF and SIMMFs only 1mm, the maximum curvature sensitivity could reach up to -78.75 dB/m-1 in the small curvature range of 0-2.36 m-1. Owing to its compact size, easy fabrication, good reproducibility and low cost, the proposed sensor is promising for bending-related high-precision engineering applications.

14.
Arch Virol ; 167(11): 2365-2370, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35857147

RESUMO

A novel double-stranded RNA (dsRNA) virus, tentatively named "Paris alphapartitivirus 1" (ParAPV1, OL960006-OL960007), was detected in Paris polyphylla var. yunnanensis plants exhibiting leaf chlorosis and shrinkage symptoms in Yunnan. Its complete genome sequence was determined using Illumina and Sanger sequencing. ParAPV1 has a bipartite genome that consists of dsRNA1 (1,917 bp) encoding the viral RNA-dependent RNA polymerase (RdRp), and dsRNA2 (1,818 bp) encoding the putative coat protein (CP). Sequence comparisons showed that the RdRp and CP of ParAPV1 are most similar to those of pear alphapartitivirus (PpPV2), with 69.97% and 54.21% amino acid sequence identities respectively. Phylogenetic analysis of the RdRp amino acid sequences of ParAPV1 and other partitiviruses showed that ParAPV1 cluster with viruses in a clade containing alphapartitiviruses, and that its closest known relatives are PpPV2 (BBA66577) and rose partitivirus (RoPV, ANQ45203S). Taken together, these results suggest that ParAPV1 should be regarded as a new member of genus Alphapartitivirus in the family Partitiviridae. This is the first report of a partitivirus infecting P. polyphylla var. yunnanensis.


Assuntos
Ascomicetos , Besouros , Liliaceae , Melanthiaceae , Vírus de RNA , Animais , Ascomicetos/genética , China , Genoma Viral , Liliaceae/genética , Filogenia , Doenças das Plantas , Vírus de RNA/genética , RNA de Cadeia Dupla/genética , RNA Viral/genética , RNA Polimerase Dependente de RNA/genética , Análise de Sequência de DNA
15.
Arch Virol ; 167(2): 645-650, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35037104

RESUMO

Paris mitovirus 1 (ParMV1) is a positive-sense RNA virus that was detected in diseased Paris polyphylla var. yunnanensis plants in Wenshan, Yunnan. The complete genome sequence of ParMV1 is 2,751 nucleotides in length, and the genome structure is typical of mitoviruses. The ParMV1 genome has a single open reading frame (ORF; nt 358-2,637) that encodes an RNA-dependent RNA polymerase (RdRp) with a predicted molecular mass of 86.42 kDa. ParMV1 contains six conserved motifs (Ι-VΙ) that are unique to mitoviruses. The 5' and 3' termini of the genome are predicted to have a stable secondary structure, with the reverse complementary sequence forming a panhandle structure. Comparative genome analysis revealed that the RdRp of ParMV1 shares 23.1-40.6% amino acid (aa) and 32.3-45.7% nucleotide (nt) sequence identity with those of other mitoviruses. Phylogenetic analysis based on RdRp aa sequences showed that ParMV1 clusters with mitoviruses and hence should be considered a new member of the genus Mitovirus in the family Mitoviridae. This is the first report of a novel mitovirus infecting Paris polyphylla var. yunnanensis.


Assuntos
Liliaceae , Vírus de RNA , China , Genoma Viral , Fases de Leitura Aberta , Filogenia , Doenças das Plantas , Vírus de RNA/genética , RNA Viral/genética
16.
Appl Opt ; 61(15): 4463-4470, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36256285

RESUMO

To nondestructively detect the mold growth process on silk, a coaxial concave reflection conical fiber optic sensor was developed using conical quartz fibers, fiber connectors, fiber couplers, and a plastic fixator. We established a theoretical model of this sensor and studied the influence of its structural parameters on its sensitivity, characterized the morphology of Aspergillus niger, and detected its growth process on a silk surface. A linear relationship between the sensor's output signal and the mold height was found. The sensor sensitivity, maximum detection error, and low limit of detection were 2.4 E-5 AU/µm, 7.83%, and 10 µm, respectively.


Assuntos
Quartzo , Seda , Tecnologia de Fibra Óptica , Modelos Teóricos , Plásticos
17.
Appl Opt ; 61(36): 10727-10734, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36606932

RESUMO

This study proposes a refractive index (RI) sensor using a cascaded tapered thin-core microfiber (TTCMF) based on the Vernier effect. The thin-core fiber was made into a TTCMF by arc discharging and flame heating and then sandwiched between two single-mode fibers (SMFs). The two structures with the same SMF-TTCMF-SMF but slightly different free spectral ranges (FSRs) were cascaded to generate the Vernier effect. The FSR varied with the taper parameters of TTCMF. The RI sensitivities of a single TTCMF sensor, series SMF-TTCMF-SMF sensor, and parallel SMF-TTCMF-SMF sensor were compared and analyzed. Using the Vernier effect in the RI measurement range from 1.3313 to 1.3392, a very high RI sensitivity of -15,053.411n m/R I U was obtained using the series SMF-TTCMF-SMF structure, and -16,723.243n m/R I U using the parallel structure, which were basically consistent with the simulation results. Compared with the RI sensitivity of the single TTCMF sensor, the RI sensitivities of series and parallel sensors were increased by 4.65 times and 5.16 times, respectively. In addition, in the temperature range from 35°C to 65°C, temperature sensitivities of -0.196n m/ ∘ C and -0.0489n m/ ∘ C were obtained using series and parallel structures, respectively; the corresponding temperature cross errors were 1.302×10-5 R I U/ ∘ C and 2.92×10-6 R I U/ ∘ C, respectively. Based on the advantages of high RI sensitivity, simple structure, low-temperature cross sensitivity, and convenient fabrication, the proposed sensors have great potential in biosensing fields.

18.
Opt Express ; 29(21): 32983-32995, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34809119

RESUMO

In the present work, we introduced a highly sensitive vibration sensor, which is based on the dispersion turning point (DTP) microfiber Mach-Zehnder interferometer. The axial strain and vibration sensing characteristics of the microfiber Mach-Zehnder interferometer were investigated. First, we theoretically analyzed the spectrum evolution characteristics of the microfiber Mach-Zehnder interferometer caused by axial strain. Second, the microfiber with different diameters was fabricated using the electrode discharge and fused taper method, and the axial strain experiments were conducted; the maximum sensitivity of the DTP microfiber with a diameter of ∼2.2 µm reached -45.55 pm/µÉ› at ∼1550 nm. Finally, based on the axial strain principle of the microfiber, we designed a highly sensitive vibration sensor using a DTP microfiber integrated into a rectangular through-hole cantilever beam. The 30-3500 Hz vibration signal monitoring could be realized, the maximum signal-to-noise ratio (SNR) was ∼75 dB at 52 Hz, and the acceleration sensitivity reached as high as 0.764 V/g at 45Hz. These results suggested the high performance of the microfiber in axial strain and micro-vibration sensing fields.

19.
Arch Virol ; 166(11): 3199-3205, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34387750

RESUMO

A novel virus, Paris virus 2 (ParV2), was isolated from diseased Paris polyphylla var. yunnanensis, and its complete genome sequence was determined and analyzed. ParV2 is a positive-sense single-stranded RNA (+ssRNA) virus with a genome size of 4,118 nucleotides. The ParV2 genome contains six putative open reading frames (ORFs) that encode proteins with predicted molecular weights of 40.14, 100.26, 7.31, 7.85, 26.09, and 8.77 kDa. The first ORF (ORF1) of ParV2 encodes a putative protein of 40.14 kDa (P40, nt: 20-1,096), whiles the second ORF (ORF2, 888 aa) containing the GDD motif encodes the highly conserved RNA-dependent RNA polymerase protein (RdRP, nt:20-2,683, P100, 100.26 kDa) of viruses in the family Tombusviridae. Multiple sequence alignments analysis showed that the complete genome sequence of ParV2 shares 31.7-55.5% nucleotide sequence identities with viruses in the family Tombusviridae. Ginger chlorotic fleck-associated tombusvirus (GCFaV-1, Accession No. QKE30557) had the highest sequence identity (55.5%) with ParV2. GCFaV-1 also shares 59.2% RdRP and 34.9% CP amino acid sequence identities with ParV2. Sequence comparisons and phylogenetic analysis of RdRP suggested that ParV2 is a novel member of the family Tombusviridae, and its closest known relative is GCFaV-1.


Assuntos
Melanthiaceae/virologia , Filogenia , Doenças das Plantas/virologia , Tombusviridae/genética , Genoma Viral , Fases de Leitura Aberta , RNA Polimerase Dependente de RNA/genética , Tombusviridae/isolamento & purificação , Proteínas Virais/genética
20.
Arch Virol ; 166(7): 2045-2050, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33944994

RESUMO

A novel negative-stranded (ns) RNA virus tentatively named "Yunnan paris negative-stranded virus" (YPNSV), was isolated from Paris polyphylla var. yunnanensis plants exhibiting leaf chlorosis and mosaic symptoms in Yunnan. Its complete genome sequence was determined using Illumina and Sanger sequencing. YPNSV has a bipartite genome that consists of a negative-stranded (ns) RNA1 encoding the viral RNA-dependent RNA polymerase (RdRp, p251), an ambisense RNA2 coding for the putative movement protein (MP, p46) and nucleocapsid protein (NP, p39), with the two open reading frames separated by a long intergenic region that is rich in A and U. Sequence comparisons showed that the RdRp, MP, and NP of YPNSV are most similar to those of watermelon crinkle leaf-associated virus 2 (WCLaV-2), with 69.1%, 50.4%, and 60.9% amino acid sequence identity, respectively. Phylogenetic analysis based on deduced amino acid sequences of RdRp and NP showed that YPNSV clustered in a clade with coguviruses and that its closest known relative is WCLaV-2. Based on the above results, YPNSV should be regarded as a new member of genus Coguvirus, family Phenuiviridae.


Assuntos
Genoma Viral/genética , Melanthiaceae/virologia , Vírus de RNA de Sentido Negativo/genética , Sequência de Aminoácidos , China , Vírus de RNA de Sentido Negativo/classificação , Fases de Leitura Aberta , Filogenia , Doenças das Plantas/virologia , RNA Viral/genética , Proteínas Virais/genética
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