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1.
Angew Chem Int Ed Engl ; 62(4): e202216838, 2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36440880

RESUMEN

The synthesis of crystalline polymer with a well-defined orientated state and a two-dimensional crystalline size beyond a micrometer will be essential to achieve the highest physical feature of polymer material but remain challenging. Herein, we show the synthesis of the crystalline unipolymer monolayer with an unusual ultrahigh modulus that is higher than the ITO substrate and high conductance by simultaneous electrosynthesis and manipulation. We find that the polymer monolayer has fully extended in the vertical and unidirectional orientation, which is proposed to approach their theoretically highest density, modulus, and conductivity among all aggregation formations of the current polymer. The modulus and current density can reach 40 and 1000 times higher than their amorphous counterpart. It is also found that these monolayers exhibit the bias- and length-dependent multiple charge states and asymmetrically negative differential resistance (NDR) effect, indicating that this unique molecular tailoring and ordering design is promising for multilevel resistive memory devices. Our work demonstrates the creation of a crystalline polymer monolayer for approaching the physical limit of polymer electronic materials and also provides an opportunity to challenge the synthetically iterative limit of an isolated ultra-long polymer.

2.
J Insect Sci ; 152015.
Artículo en Inglés | MEDLINE | ID: mdl-26546689

RESUMEN

In insects, the frequency distribution of the measurements of sclerotized body parts is generally used to classify larval instars and is characterized by a multimodal overlap between instar stages. Nonparametric methods with fixed bandwidths, such as histograms, have significant limitations when used to fit this type of distribution, making it difficult to identify divisions between instars. Fixed bandwidths have also been chosen somewhat subjectively in the past, which is another problem. In this study, we describe an adaptive kernel smoothing method to differentiate instars based on discontinuities in the growth rates of sclerotized insect body parts. From Brooks' rule, we derived a new standard for assessing the quality of instar classification and a bandwidth selector that more accurately reflects the distributed character of specific variables. We used this method to classify the larvae of Austrosimulium tillyardianum (Diptera: Simuliidae) based on five different measurements. Based on head capsule width and head capsule length, the larvae were separated into nine instars. Based on head capsule postoccipital width and mandible length, the larvae were separated into 8 instars and 10 instars, respectively. No reasonable solution was found for antennal segment 3 length. Separation of the larvae into nine instars using head capsule width or head capsule length was most robust and agreed with Crosby's growth rule. By strengthening the distributed character of the separation variable through the use of variable bandwidths, the adaptive kernel smoothing method could identify divisions between instars more effectively and accurately than previous methods.


Asunto(s)
Simuliidae/crecimiento & desarrollo , Animales , Cabeza/anatomía & histología , Cabeza/crecimiento & desarrollo , Larva/anatomía & histología , Larva/crecimiento & desarrollo , Simuliidae/anatomía & histología
3.
Genes (Basel) ; 14(10)2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37895216

RESUMEN

The pinion-streaked snout Schrankia costaestrigalis is a new potato pest that has recently been recorded in China. In this study, we analyzed the complete mitochondrial genome of S. costaestrigalis. The results revealed the mitogenome (GenBank: OQ181231) to occur as a circular DNA molecule of 16,376 bp with 51.001% AT content, including 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and 1 control region. Notably, the PCGs exhibited typical ATN (Met) start codons, including cox1, which deviated from the usual CGA start codon observed in other lepidopteran mitogenomes, and followed the conventional TAN stop codons. The 22 tRNA genes demonstrated the ability to form a cloverleaf structure, with the exception of trnS1-NCU, which lacked the DHU arm present in other Erebidae mitogenomes. Additionally, conserved motifs like "ATAGA + poly-T (19 bp) stretch" and five microsatellite-like elements (TA) were identified in the AT-rich region. The phylogenetic trees revealed that the Hypenodinae subfamily forms an independent lineage closely related to Erebinae and Catocalinae. The comprehensive mitogenome of S. costaestrigalis will greatly enhance future studies focused on the molecular classification and phylogenetic understanding of the Hypenodinae subfamily within the larger family Erebidae.


Asunto(s)
Genoma Mitocondrial , Mariposas Nocturnas , Animales , Filogenia , Mariposas Nocturnas/genética , ARN de Transferencia/genética , ARN de Transferencia/química , Codón de Terminación
4.
PeerJ ; 10: e14067, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36193428

RESUMEN

Despite the significant progress that has been made in the genome sequencing of Beauveria species, mitochondrial genome (mitogenome) used to examine genetic diversity within fungal populations. Complete mitogenomes of Beauveria species can be easily sequenced and assembled using various sequencing techniques. However, since mitogenome annotations are mainly derived from similar species comparison and software prediction, and are not supported by RNA-seq transcripts data, it leads to problems with the accuracy of mitochondrial annotations and the inability to understand RNA processing. In this study, we assembled and annotated the mitogenome of eight Beauveria strains using Illumina DNA and RNA sequencing data. The circular mitogenome of eight Beauveria strains ranged from 26,850 bp (B. caledonica strain ATCC 64970) to 35,999 bp (B. brongniartii strain GYU-BMZ03), with the intronic insertions accounting for most of the size variation, thus contributing to a total mitochondrial genome (mitogenome) size of 7.01% and 28.95%, respectively. Intron number variations were not directly related to the evolutionary relationship distance. Besides ribosomal protein S3 (rps3), most introns are lost too quickly and lack the stability of protein-coding genes. The short RNA-seq reads from next-generation sequencing can improve the mitochondrial annotation accuracy and help study polycistronic transcripts and RNA processing. The transcription initiation sites may be located in the control region. Most introns do not serve as taxonomic markers and also lack open reading frames (ORFs). We assumed that the poly A tail was added to the polycistronic transcript before splicing and one polycistronic transcript (trnM (1)-trnL (1)-trnA-trnF-trnK-trnL (2)-trnQ-trnH-trnM (2)-nad2-nad3-atp9-cox2-trnR (1)-nad4L-nad5-cob-trnC-cox1-trnR (2)-nad1-nad4-atp8-atp6-rns-trnY-trnD-trnS-trnN-cox3-trnG-nad6-trnV-trnI-trnS-trnW-trnP-rnl(rps3)-trnT-trnE-trnM (3)) was first processed from the mitogenome and was subsequently processed into smaller mono-, di-, or tricistronic RNAs.


Asunto(s)
Beauveria , Genoma Mitocondrial , Genoma Mitocondrial/genética , Beauveria/genética , Secuencia de Bases , Mapeo Cromosómico , Intrones
5.
Mitochondrial DNA B Resour ; 6(10): 2946-2948, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34553052

RESUMEN

The genus Morphostenophanes is a small arboreal group of darkling beetles that are endemic to the Oriental region. The complete mitochondrial genome of the M. sinicus population from the Manwan Town was first characterized. The mitogenome consisted of a circular DNA molecule of 15,662 bp with a 66.352% AT content. It comprises 13 protein-coding genes (PCGs), 22 tRNA genes, and two rRNA genes. The PCGs have a typical ATN (Met) start codon, except for nad1 (TTG as a start codon), and are terminated by typical TAN stop codons.

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