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1.
Nano Lett ; 24(11): 3498-3506, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38440992

RESUMO

Solar distillation is a promising approach for addressing water scarcity, but relentless stress/strain perturbations induced by wind and waves would inevitably cause structural damage to solar absorbers. Despite notable advances in efficient solar absorbers, there have been no reports of compliant and robust solar absorbers withstanding practical mechanical impacts. Herein, an elastic and robust hydrogel absorber that exhibited a high level of evaporation performance was fabricated by introducing ion-coordinated MXene nanosheets as photothermal conversion units and mechanically enhanced fillers. The ion-coordinated MXene nanosheets acting as strong cross-linking points provided excellent elasticity and robustness to the hydrogel absorber. As a result, the evaporation rate of hydrogel absorber, with a high initial value of 2.61 kg m-2 h-1 under one sun irradiation, remained at 2.15 kg m-2 h-1 under a 100% tensile strain state and 2.40 kg m-2 h-1 after 10 000 stretching-releasing cycles. This continuous and stable water desalination approach provides a promising device for actual seawater distillation.

2.
Nano Lett ; 23(13): 6216-6225, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37341290

RESUMO

It remains a challenge to artificially fabricate fibers with the macroscopic mechanical properties and characteristics of spider silk. Herein, a covalently cross-linked double-network strategy was proposed to disrupt the inverse relation of strength and toughness in the fabrication of ultratough and superstrong artificial polymer fibers. Our design utilized a strong fishnet-like structure based on immovable cellulose nanocrystal cross-links to mimic the function of the ß-sheet nanocrystallites and a slidable mechanically interlocked network based on polyrotaxane to imitate the dissipative stick-slip motion of the ß-strands in spider silk. The resultant fiber exhibited superior mechanical properties, including gigapascal tensile strength, a ductility of over 60%, and a toughness exceeding 420 MJ/m3. The fibers also showed robust biological functions similar to those of spider silks, demonstrating mechanical enhancement, energy absorption ability, and shape memory. A composite with our artificial fibers as reinforcing fibers exhibited remarkable tear and fatigue resistance.

3.
Int J Mol Sci ; 25(11)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38891989

RESUMO

Negeviruses are insect-specific enveloped RNA viruses that exhibit a wide geographic distribution. A novel nege-like virus, tentatively named Aphis gossypii nege-like virus (AGNLV, GenBank: OR880429.1), was isolated from aphids (Aphis gossypii) in Lijiang City, Yunnan, China. AGNLV has a genome sequence of 9258 nt (excluding the polyA tail) encoding three open reading frames (ORFs). ORF1 (7149 nt) encodes a viral methyltransferase, a viral RNA helicase, and an RNA-dependent RNA polymerase. ORF2 (1422 nt) encodes a DiSB-ORF2_chro domain and ORF3 encodes an SP24 domain. The genome sequence of AGNLV shares the highest nucleotide identity of 60.0% and 59.5% with Wuhan house centipede virus 1 (WHCV1) and Astegopteryx formosana nege-like virus (AFNLV), respectively. Phylogenetic analysis based on the RNA-dependent RNA polymerase shows that AGNLV is clustered with other negeviruses and nege-like viruses discovered in aphids, forming a distinct "unclassified clade". Interestingly, AGNLV only encodes three ORFs, whereas AFNLV and WHCV1 have four ORFs. Structure and transmembrane domain predictions show the presence of eight alpha helices and five transmembrane helices in the AGNLV ORF3. Translational enhancement of the AGNLV 5' UTR was similar to that of the 5' UTR of plant viruses. Our findings provide evidence of the diversity and structure of nege-like viruses and are the first record of such a virus from a member of the genus Aphis.


Assuntos
Afídeos , Genoma Viral , Fases de Leitura Aberta , Filogenia , Animais , Afídeos/virologia , China , Vírus de RNA/genética , Vírus de RNA/isolamento & purificação , Vírus de RNA/classificação , RNA Polimerase Dependente de RNA/genética , Proteínas Virais/genética , Proteínas Virais/química , Vírus de Insetos/genética , Vírus de Insetos/isolamento & purificação , Vírus de Insetos/classificação , RNA Viral/genética
4.
Vascular ; : 17085381231192688, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37522318

RESUMO

BACKGROUND: Abdominal aortic aneurysm (AAA) is a potentially fatal vascular disorder with a high mortality rate. It was previously reported that fibroblast growth factor 21 (FGF21) was highly expressed in AAA patients. Nonetheless, its underlying mechanism in AAA progression is unclarified. METHODS: Angiotensin II (Ang-II) was used to induce AAA in human aortic vascular smooth muscle cells (HASMCs) and mouse models. Western blotting and RT-qPCR were utilized for measuring protein and RNA levels. Immunofluorescence staining was utilized for detecting LC3B expression in HASMCs. Elastica van Gieson staining was conducted for histological analysis of the abdominal aortas of mice. RESULTS: FGF21 displayed a high level in Ang-II-stimulated HASMCs and AAA mice. FGF21 depletion ameliorated abdominal aorta dilation and Ang-II-triggered pathological changes in mice. FGF21 silencing hindered autophagy and PI3K/AKT/mTOR pathway. CONCLUSIONS: FGF21 contributes to AAA progression by enhancing autophagy and activating PI3K/AKT/mTOR pathway.

5.
J Nematol ; 55(1): 20220036, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37143485

RESUMO

Meloidogyne paramali n. sp. was detected from Japanese maple trees (Acer palmatum) from Chiba, Japan during quarantine inspections in China. This species is characterized by second-stage juveniles (J2) with short tail length 32.2 (24-36.8) µm, finely rounded to broadly pointed tail terminus with extremely short hyaline tail terminus 4.3 (3.0-4.9) µm; perineal patterns of females characterized by an oval or irregular appearance, with round and low dorsal arch, and fine and smooth striae. M. paramali n. sp. is very similar to M. mali in that the perineal pattern has fine, smooth striae and both J2 have a short tail, but it can be distinguished from the latter by perineal pattern of the female (lateral field distinct vs. indistinct), shorter J2 hyaline tail terminus (4.3 [3.0-4.9] µm vs. 8.2 [4.8-12.7] µm, and by J2 tail with finely rounded to broadly pointed tail terminus, never sharply pointed vs. finely rounded and almost pointed. The polytomous key codes of the new species are as follows: Female: A21, B2, C32, D4; Male: A21, B3, C2, D1, E2, F2; J2: A2, B23, C43, D34, E12, F34. Detailed phylogenetic analysis based on partial 18S, ITS, D2-D3 28S, and partial mtCOI sequences also confirmed it as a new species, which is very close to M. mali and M. vitis and forms molecular group VIII. M. marylandi and other Meloidogyne species detected from plants from Japan in China are also discussed.

6.
Fish Physiol Biochem ; 48(6): 1539-1554, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36266516

RESUMO

Fenpropathrin has been a commonly used insecticide to control agricultural and household insects over a few decades. Up to now, fenpropathrin residue in soil and water has been often determined due to its widespread use, which poses serious threat to environment and aquatic organisms. The potential of fenpropathrin to affect aquatic lives is still poorly understood. In this study, we used zebrafish (Danio rerio) embryo as an experimental model system to evaluate the toxicity of fenpropathrin to the development of zebrafish nervous system. Zebrafish embryos were separately exposed to fenpropathrin at the dose of 0.016 mg/L, 0.032 mg/L, 0.064 mg/L, starting at 6 h post-fertilizationhpf (hpf) up to 96 hpf. The results showed that fenpropathrin exposure gives rise to physiological, behavioral, and neurodevelopmental impairments in zebrafish embryos, including enhanced acetylcholinesterase (AChE) activity, abnormal swimming behavior, karyopyknosis in brain cells, increased intercellular space, and uneven migration of neuron in brain area. In addition, the expressions of genes concerning neurodevelopment and neurotransmitter system were inhibited following fenpropathrin exposure. We also found that fenpropathrin exposure distinctly induced oxidative stress by increasing reactive oxygen species (ROS) generation and inhibiting the production of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). Expectedly, some apoptosis-associated genes were induced and the apoptosis appeared in the brain and heart cells of zebrafish embryos. Moreover, fenpropathrin exposure also inhibited the expressions of genes in Nrf2 signaling pathway, such as heme oxygenase-1 (HO-1) and SOD. In summary, the results of this study indicate that oxidative stress-triggered apoptosis may be an underlying fundamental of fenpropathrin-induced neurotoxicity in zebrafish embryos.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Acetilcolinesterase/metabolismo , Estresse Oxidativo/genética , Superóxido Dismutase/metabolismo , Embrião não Mamífero/metabolismo , Poluentes Químicos da Água/toxicidade
7.
Sensors (Basel) ; 21(22)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34833746

RESUMO

Aimed at the problems in which the performance of filters derived from a hypothetical model will decline or the cost of time of the filters derived from a posterior model will increase when prior knowledge and second-order statistics of noise are uncertain, a new filter is proposed. In this paper, a Bayesian robust Kalman filter based on posterior noise statistics (KFPNS) is derived, and the recursive equations of this filter are very similar to that of the classical algorithm. Note that the posterior noise distributions are approximated by overdispersed black-box variational inference (O-BBVI). More precisely, we introduce an overdispersed distribution to push more probability density to the tails of variational distribution and incorporated the idea of importance sampling into two strategies of control variates and Rao-Blackwellization in order to reduce the variance of estimators. As a result, the convergence process will speed up. From the simulations, we can observe that the proposed filter has good performance for the model with uncertain noise. Moreover, we verify the proposed algorithm by using a practical multiple-input multiple-output (MIMO) radar system.


Assuntos
Algoritmos , Ruído , Teorema de Bayes , Radar
8.
J Nematol ; 532021.
Artigo em Inglês | MEDLINE | ID: mdl-34761225

RESUMO

A stunt nematode species, Quinisulcius curvus, recovered from the rhizosphere of sea randa (Guettarda speciosa), is described and characterized herein based on integrative taxonomy. Morphometrics and distribution of all reported populations of Q. curvus are also discussed. The Chinese population of Q. curvus displayed slight variation in stylet length; however, the rest of the characters matches well with the original description. This is the first record of Q. curvus from Hainan, China, and the first molecular characterization for this species. Phylogenetic analysis based on partial 18S, 28S and ITS sequences placed Q. curvus with related stunt nematodes species, but clearly separated from them. The present study expanded the geographic record and provided molecular data on Q. curvus from China.

9.
Nanotechnology ; 31(33): 335504, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32353833

RESUMO

Flexible sensors at small scales have potential applications in many fields. Until now, the research on high-performance vibration sensors based on soft materials with high sensitivity and precision, fast response and high stability are still in its infancy. In this work, a flexible, wearable and high precision film sensor based on multi-walled carbon nanotube (MWCNT) was prepared via a vacuum filtration process and then encapsulated within polydimethylsiloxane (PDMS). The sensor exhibits an ultrahigh sensitivity with gauge factor of 214.3 at flexural strain of 0.4%. When used to monitor the vibration responses of a carbon-fiber beam induced by the base excitation and impact hammer, the time and frequency responses were comparable with the results obtained by the accelerometer, with difference less than 1\!%. In addition, when the MWCNT/PDMS thin film was employed as an electronic skin sensor attached on the human body to detect human activities, the high sensitivity and repeatability demonstrate a great potential application in monitoring human motion.

10.
Reprod Fertil Dev ; 32(9): 879-884, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32448404

RESUMO

This study investigated the possibility of a sealed culture system in polymerase chain reaction (PCR) tubes to maintain embryo development. The embryo density that could support the development of 2-cell stage mouse embryos to the hatching stage was determined. At an embryo density of 1:2 (100 embryos cultured in 200µL CZB medium that had been pretreated with a reference gas containing 5% O2), the developmental rate was higher and fewer embryos exhibited reactive oxygen species- or hypoxia-induced injury compared with other sealed culture groups. Expression of growth factors (insulin-like growth factor (IGF) 1, IGF2, epidermal growth factor and transforming growth factor-α) and their receptors was evaluated, with similar expression patterns seen for embryos in sealed culture (5% O2, embryo density of 1:2) compared with the control group (embryos cultured in microdrops and placed in a 37°C, 5% CO2 water-jacketed incubator; P>0.05). After transfer of blastocysts generated by the sealed culture into recipients, there were no obvious differences in the rate of normal live pups births between the sealed culture and control groups (P>0.05). Thus, the sealed embryo culture system in PCR tubes is feasible for use in situations which cannot use a traditional incubator, such as in space and during the transport of embryos.


Assuntos
Blastocisto/metabolismo , Técnicas de Cultura Embrionária/instrumentação , Oxigênio/metabolismo , Animais , Apoptose , Blastocisto/patologia , Transferência Embrionária , Desenho de Equipamento , Feminino , Fertilização in vitro , Regulação da Expressão Gênica no Desenvolvimento , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Nascido Vivo , Masculino , Camundongos , Gravidez , Taxa de Gravidez , Espécies Reativas de Oxigênio/metabolismo
11.
J Nematol ; 522020.
Artigo em Inglês | MEDLINE | ID: mdl-33829168

RESUMO

Bursaphelenchus yongensis was first reported in China, and later found in Japan and Korea. It is characterized by a relatively slim body (a = 42 and 57 for females and males, respectively). The excretory pore is located at level of median bulb, the lateral field has three lines, and a small vulval flap is present. A long post-uterine branch extends 2/3 to 3/4 of the vulva to anus distance. The conoid female tail has a 2-5 µm long mucron in the central position at the terminus. Spicules are small, condylus high and strongly dorsally bent. Subsequently Bursaphelenchus uncispicularis was described from China. Both morphological characters and morphometrics are very similar to B. yongensis, except for the number of lateral lines (4 vs 3) and male caudal papillae (7 vs 4). Re-examination of type material and a Beijing population of B. yongensis determined that B. yongensis has 7 caudal papillae instead of 4 as originally reported. It is possible that the poor condition of the type specimens of B. uncispicularis could have created difficulty in the determination of lateral line number. Unfortunately, type material of B. uncispicularis has been lost. Therefore, there is no evidence that B. uncispicularis exists. It is now established that B. yongensis is present in China, Japan and Korea with a common host species (P. thunbergii) and a common widespread vector (Cryphalus fulvus). Therefore, based on the geographic, ecological, molecular, and morphological data, we propose Bursaphelenchus uncispicularis Zhuo, Li, Li, Yu & Liao, 2007 as a junior synonym of B. yongensis Gu, Braasch, Burgermeister, Brandstetter & Zhang, 2006.

12.
J Nematol ; 522020.
Artigo em Inglês | MEDLINE | ID: mdl-33829187

RESUMO

Root-knot nematode, Meloidogyne mali can cause damage in trees, shrubs, and herbaceous plants, and was placed on the EPPO Alert List in 2014. In the present study, we report a population isolated from Japanese maple. The recovered population is described by detailed morphological and molecular approaches. The molecular phylogentic analysis based on 28S rRNA, ITS, and mitochondrial COI genes places the population in the clade together with other M. mali sequences available in GenBank. The cloned sequences of the 28S rRNA gene revealed a high intragenomic rRNA polymorphism where the polymorphic copies are spread across M. mali clade. Similarly, we also found high variation in the mitochondrial COI gene. Among four haplotypes in M. mali, three occur in the newly found population. Our study provides the first report of intragenomic polymorphism in M. mali, and the results suggest that intragenomic polymorphism maybe widespread in Meloidogyne.

13.
J Nematol ; 52: 1, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32180385

RESUMO

Laimaphelenchus sinensis n. sp. isolated from declining Chinese pine, Pinus tabuliformis Carrière, is described and characterized morphologically and molecularly. The new species has four incisures in the lateral field and the excretory pore situated posterior to the nerve ring; the female has a vulval flap and vaginal sclerotization is quite prominent in majority of specimens. The female tail is conoid, ventrally curved having a single stalk-like terminus with 8 to 10 projections. The male spicules are 14.0 (13.2-15) µm long along curved median line and tail is ventrally curved typical of the genus; however, the projections are less prominent as compared to those of female. The male has two pairs of caudal papillae and Bursa is absent. Phylogenetically, the ribosomal DNA sequences of the new species placed it within Laimaphelenchus clade and are morphologically similar to L. persicus, L. preissii, L. simlaensis and L. unituberculus.Laimaphelenchus sinensis n. sp. isolated from declining Chinese pine, Pinus tabuliformis Carrière, is described and characterized morphologically and molecularly. The new species has four incisures in the lateral field and the excretory pore situated posterior to the nerve ring; the female has a vulval flap and vaginal sclerotization is quite prominent in majority of specimens. The female tail is conoid, ventrally curved having a single stalk-like terminus with 8 to 10 projections. The male spicules are 14.0 (13.2-15) µm long along curved median line and tail is ventrally curved typical of the genus; however, the projections are less prominent as compared to those of female. The male has two pairs of caudal papillae and Bursa is absent. Phylogenetically, the ribosomal DNA sequences of the new species placed it within Laimaphelenchus clade and are morphologically similar to L. persicus, L. preissii, L. simlaensis and L. unituberculus.

14.
J Nematol ; 52: 1-11, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32185944

RESUMO

Seinura italiensis n. sp. isolated from the medium soil imported from Italy is described and illustrated using morphological and molecular data. The new species is characterized by having short body (477 (407-565) µm and 522 (469-590) µm for males and females, respectively), three lateral lines, stylet lacking swellings at the base, and excretory pore at the base or slightly anterior to base of metacorpus; females have 58.8 (51.1-69.3) µm long post-uterine sac (PUS), elongate conical tail with its anterior half conoid, dorsally convex, and ventrally slightly concave and the posterior half elongated, narrower, with finely rounded to pointed tip and males having seven caudal papillae and 14.1 (12.6-15.0) µm long spicules. Morphologically, the new species is similar to S. caverna, S. chertkovi, S. christiei, S. hyrcania, S. longicaudata, S. persica, S. steineri, and S. tenuicaudata. The differences of the new species with aforementioned species are discussed. In molecular phylogenetic analyses using near full-length small and large subunit ribosomal DNA (SSU and LSU rDNA D2-D3 expansion segments) sequences, the new species fell into a clade including three previously described/sequenced species of the genus in both SSU and LSU Bayesian phylogenetic trees.Seinura italiensis n. sp. isolated from the medium soil imported from Italy is described and illustrated using morphological and molecular data. The new species is characterized by having short body (477 (407-565) µm and 522 (469-590) µm for males and females, respectively), three lateral lines, stylet lacking swellings at the base, and excretory pore at the base or slightly anterior to base of metacorpus; females have 58.8 (51.1-69.3) µm long post-uterine sac (PUS), elongate conical tail with its anterior half conoid, dorsally convex, and ventrally slightly concave and the posterior half elongated, narrower, with finely rounded to pointed tip and males having seven caudal papillae and 14.1 (12.6-15.0) µm long spicules. Morphologically, the new species is similar to S. caverna, S. chertkovi, S. christiei, S. hyrcania, S. longicaudata, S. persica, S. steineri, and S. tenuicaudata. The differences of the new species with aforementioned species are discussed. In molecular phylogenetic analyses using near full-length small and large subunit ribosomal DNA (SSU and LSU rDNA D2-D3 expansion segments) sequences, the new species fell into a clade including three previously described/sequenced species of the genus in both SSU and LSU Bayesian phylogenetic trees.

15.
J Nematol ; 512019.
Artigo em Inglês | MEDLINE | ID: mdl-34179795

RESUMO

Ektaphelenchus koreanus n. sp. is isolated from Pinus packaging wood from Korea in Ningbo customs. The new species can be characterized by having four incisures in the lateral field, the excretory pore located posterior to nerve ring, female devoid of vulval flap, and having long post-vulval intestinal sac (55-106 µm), tail with a finely rounded terminus. Six caudal papillae in male and spicule short (12.7-13.7 µm), having broad squared to rounded condylus, triangular rounded rostrum, cucullus absent. Morphologically the species is most similar with E. berbericus, E. joyceae, E. oleae, E. ibericus, and E. taiwanensis but it can be differentiated by plenty of morphometrical and morphological characters. In addition, a morphometry table of Ektaphelenchus is also presented.

16.
J Nematol ; 50(1): 69-76, 2018 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-30335913

RESUMO

Three populations of neotylenchid nematodes were isolated in Ningbo, P. R. China, from white pine lumber (Pinus monticola) imported from the USA. The nematodes were morphologically intermediate between Hexatylus and Deladenus. The nematodes were molecularly characterized based on sequences of the rDNA small subunit 18S, large subunit 28S D2/D3, and internal transcribed spacer sequences. The phylogenetic inferences placed the nematodes with other neotylenchid nematodes, i.e., Fergusobia and Rubzovinema. Based on the morphology and phylogenetic analysis, this nematode is described herein as Delatylus andersoni n. gen., n. sp. The new genus/species is characterized by the female body habitus ranging from nonobese to semiobese and from straight to dorsally curved when heat relaxed, cephalic framework with six unequal sized lip sectors, lateral fields having 10 to 12 lines, 4 to 5 guide rings on the stylet, excretory pore posterior to the nerve ring, spermatheca diminished or absent, vulvar opening large, and relative proximity of vulva to the anus. Detailed morphological and molecular characterization of the new genus/species is presented along with the comparison of the related genera.

17.
J Nematol ; 50(3): 369-386, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30451421

RESUMO

Xiphinema parachambersi n. sp. recovered in Ningbo, China, from the rhizosphere of ornamental plants ( Gardenia jasminoides and Euonymus hamiltonianus ) imported from Japan is described. The new species is characterized by a long female body 1,830 to 2,109 µ m long, odontostyle 105 to 116 µ m long, reproductive system mono-opisthodelphic, vulva located anteriorly at 25.2 to 27.7% of total body, long ovary 119 to 292 µ m with simple uterus and Z-organ absent, female tail elongated conoid with a rounded terminus. Only two juvenile stages were available to study and no male was found. The polytomous identification codes for this new species are A1, B4, C2, D23, E1, F2, G2, H2, I2, J2, K?, L1 and it belongs to the morphospecies group 1. Phylogenetic analysis based on the 18S, ITS1 and 28S D2/D3 sequences of the new species showed close relationships with X. chambersi . Morphologically, the new species is similar to X. chambersi , X. hangzhouense , and X. winotoi but can be differentiated by morphological characters and DNA sequences. To help identify the species, a diagnostic key to the group 1 species is presented.

18.
J Nematol ; 49(4): 404-417, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29353930

RESUMO

Xiphinema japonicum n. sp., isolated in Ningbo, China, from the rhizosphere of Podocarpus macrophyllus (Thunb.) imported from Japan is described. The new species belongs to Xiphinema non-americanum group 7 and is characterized by medium body length (3.0-3.7 mm), total stylet length 190-201 µm, vulva located anteriorly (V = 30.5%-35.3%), two equally developed female genital branches without uterine differentiation (no Z or pseudo-Z organ and/or spines in the uteri), short tail, convex-conoid with subdigitate peg in terminus, and absence of males. The species has four juvenile developmental stages (J1 was not found). The polytomous identification codes of the new species are (codes in parentheses are exceptions) A4-B4-C4-D5(4)-E2(3)-F3(4)-G2(3)-H2-I3-J4-K?-L1. Morphologically, the new species is mainly characterized by combination of the codes C4 and E2(3), making the species unique and different from other species in the genus. It is most similar to the North American species Xiphinema bakeri, herein considered as its cryptic species by the nature of high morphological similarity, but with significant differences in DNA sequences in nearly full length 18S, ITS1, 28S D2/D3, and cytochrome c oxidase subunit 1 sequences. The second morphologically close species is Xiphinema setariae from which the new species could be separated based on morphological and molecular characters. Morphological comparisons with phylogenetically related species are also discussed.

19.
J Nematol ; 49(2): 168-176, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28706317

RESUMO

Deladenus posteroporus n. sp. isolated from packaging wood originated from Canada and from white pine lumber from the United States, both intercepted in the port of Ningbo, China, is described and illustrated. Both mycetophagous and infective forms were recovered from the Canadian sample, whereas only the mycetophagous form was found in the U.S. SAMPLE: The new species is characterized by the posteriorly positioned excretory pore relative to the hemizonid in both mycetophagous and infective forms, by a broadly rounded tail end in mycetophagous females and lateral fields with 11 to 12 lines midbody in both mycetophagous females and males. The partial 18S, complete internal transcribed spacer, and partial 28S D2/D3 rRNA genes were amplified and sequenced. Phylogenetic analyses of the genes grouped the new species with previously sequenced species of Deladenus in a fully supported clade. This is the first report of Deladenus species with a known infective stage to have the excretory pore positioned posterior to the hemizonid.

20.
J Nematol ; 48(1): 34-42, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27168651

RESUMO

Aphelenchoides fuchsi sp. n. is described and illustrated from bark and wood samples of a weakened Mondell pine in Kermanshah Province, western Iran. The new species has body length of 332 to 400 µm (females) and 365 to 395 µm (males). Lip region set off from body contour. The cuticle is weakly annulated, and there are four lines in the lateral field. The stylet is 8 to 10 µm long and has small basal swellings. The excretory pore is located ca one body diam. posterior to metacorpus valve or 51 to 62 µm from the head. The postuterine sac well developed (60-90 µm). Spicules are relatively short (15-16 µm in dorsal limb) with apex and rostrum rounded, well developed, and the end of the dorsal limb clearly curved ventrad like a hook. The male tail has usual three pairs of caudal papillae (2+2+2) and a well-developed mucro. The female tail is conical, terminating in a complicated step-like projection, usually with many tiny nodular protuberances. The new species belongs to the Group 2 sensu Shahina, category of Aphelenchoides species. Phylogenetic analysis based on small subunit (SSU) and partial large subunit (LSU) sequences of rRNA supported the morphological results.

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