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1.
Molecules ; 28(9)2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37175298

RESUMO

Based on the DFT calculations, two-dimensional (2D) R-graphyne has been demonstrated to have high stability and good conductivity, which can be conducive to the relevant electrocatalytic activity of the material. Different from the poor graphene, R-graphyne, which is completely composed of anti-aromatic structural units, can exhibit certain HER catalytic activity. In addition, doping the TM atoms in Group VIIIB can be considered an effective strategy to enhance the HER catalytic activity of R-graphyne. Particularly, Fe@R-graphyne, Os@R-graphyne, Rh@R-graphyne and Ir@R-graphyne can exhibit higher HER catalytic activities due to the formation of more active sites. Usually, the shorter the distance between the TM and C atoms is, the better the HER activity of the C-site is. Furthermore, doping Ni and Rh atoms of Group VIIIB can significantly improve the OER catalytic performance of R-graphyne. It can be found that ΔGO* can be used as a good descriptor for the OER activities of TM@R-graphyne systems. Both Rh@R-graphyne and Ni@R-graphyne systems can exhibit bifunctional electrocatalytic activities for HER/OER. In addition, all the relevant catalytic mechanisms are analyzed in detail. This work not only provides nonprecious and highly efficient HER/OER electrocatalysts, but also provides new ideas for the design of carbon-based electrocatalysts.

2.
Plant Biotechnol J ; 20(3): 554-563, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34695276

RESUMO

Wheat stem (or black) rust, caused by Puccinia graminis f. sp. tritici (Pgt), has been historically among the most devastating global fungal diseases of wheat. The recent occurrence and spread of new virulent races such as Ug99 have prompted global efforts to identify and isolate more effective stem rust resistance (Sr) genes. Here, we report the map-based cloning of the Ug99-effective SrTm5 gene from diploid wheat Triticum monococcum accession PI 306540 that encodes a typical coiled-coil nucleotide-binding leucine-rich repeat protein. This gene, designated as Sr22b, is a new allele of Sr22 with a rare insertion of a large (13.8-kb) retrotransposon into its second intron. Biolistic transformation of an ~112-kb circular bacterial artificial chromosome plasmid carrying Sr22b into the susceptible wheat variety Fielder was sufficient to confer resistance to stem rust. In a survey of 168 wheat genotypes, Sr22b was present only in cultivated T. monococcum subsp. monococcum accessions but absent in all tested tetraploid and hexaploid wheat lines. We developed a diagnostic molecular marker for Sr22b and successfully introgressed a T. monococcum chromosome segment containing this gene into hexaploid wheat to accelerate its deployment and pyramiding with other Sr genes in wheat breeding programmes. Sr22b can be a valuable component of gene pyramids or transgenic cassettes combining different resistance genes to control this devastating disease.


Assuntos
Basidiomycota , Resistência à Doença , Triticum , Alelos , Mapeamento Cromossômico , Resistência à Doença/genética , Genes de Plantas/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Triticum/genética , Triticum/microbiologia
3.
Plant Dis ; 106(3): 901-905, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34546784

RESUMO

Oat stem rust, caused by Puccinia graminis f. sp. avenae, is one of the most devastating diseases of oat. The most cost-effective and environmentally friendly strategy to control this disease is the use of resistant cultivars. However, P. graminis f. sp. avenae can overcome the resistance of cultivars by rapidly changing its virulence. Thus, information on the virulence of P. graminis f. sp. avenae populations and resistance of cultivars is critical to control the disease. The current study was conducted to monitor the virulence composition and dynamics of the P. graminis f. sp. avenae population in China and to evaluate resistance of oat cultivars. Oat leaves naturally infected by P. graminis f. sp. avenae were collected in 2018 and 2019, and 159 isolates were derived from single uredinia. The isolates were tested on 12 international differential lines, and eight races, TJJ, TBD, TJB, TJD, TJL, TJN, TGD, and TKN, were identified for the first time in China. The predominant race was TJD, virulent against Pg1, Pg2, Pg3, Pg4, Pg8, Pg9, and Pg15, accounting for 35.8 and 37.8% in 2018 and 2019, respectively. The sub-predominant races were TJN (30.2% in 2018, 28.3% in 2019) and TKN (20.8% in 2018, 12.3% in 2019). All isolates were virulent to Pg1, Pg2, Pg3, and Pg4, and avirulent to Pg6 and Pg16. The three predominant races (TJD, TJN, and TKN) were used to evaluate resistance in 30 Chinese oat cultivars at the seedling and adult plant stages. Five cultivars, Bayan 1, Baiyan 2, Baiyan 3, Baiyan 5, and Baiyan 9, were highly resistant to the three races at both seedling and adult plant stages. The results of the virulences and frequencies of P. graminis f. sp. avenae races and the resistant cultivars will be useful in elucidating the pathogen migration and evolution and for breeding oat cultivars with stem rust resistance.


Assuntos
Avena , Resistência à Doença , Puccinia , China , Resistência à Doença/genética , Melhoramento Vegetal , Doenças das Plantas , Virulência/genética
4.
Aesthetic Plast Surg ; 45(6): 2781-2787, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34244833

RESUMO

BACKGROUND: Many techniques have been introduced to correct cryptotia. The previous methods are releasing the constricted cartilage and changing the mechanical fulcrum partly to the right position. However, some patients are still not satisfied with the treatment results, due to cryptotia recurrence and insufficient superior 1/3 width. This study aimed to develop a new method for completely changing the mechanical direction of constricted cartilage for correcting cryptotia. METHODS: From 2007 to 2020, twenty-four cryptotia patients were treated. During surgical reconstruction, the retroauricular skin flap was elevated, the posterior aspect of the upper auricular cartilage was completely exposed, and the abnormal insertion of the auricular intrinsic muscles detached. The sharply curved antihelical cartilage was cut and overturned, and the scalp skin flap was undermined and advanced toward the postauricular sulcus. The edge of the retroauricular scalp flap is fixed on the mastoid periosteum. The incision was closed. RESULTS: Eighteen patients had unilateral cryptotia, and six had bilateral cryptotia. Relatively favorable results were obtained in the follow-up period (range, 6-48 months). There were no cases of skin necrosis, complications, or revision surgery. CONCLUSIONS: The main advantages of this technique are the surgically reproducible results, and that it can be applied to most cases. The method described in this paper could potentially increase the width of the upper third of the auricle and reduce recurrence rate, while also leaving an inconspicuous scar and a satisfactory auricular contour. It is suggested that this technique could be an alternative method of cryptotia correction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Pavilhão Auricular , Procedimentos de Cirurgia Plástica , Pavilhão Auricular/cirurgia , Cartilagem da Orelha/cirurgia , Orelha Externa/cirurgia , Humanos , Retalhos Cirúrgicos
5.
Mol Biol Rep ; 47(6): 4303-4309, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32418113

RESUMO

Wheat stem rust, caused by Puccinia graminis f. sp. tritici (Pgt), is a fungus that causes the devastating fungalwheat stem rust disease in wheat production. Rapid identification of the physiological races of Pgt are very importance for the prevention of wheat stem rust. In this paper we developed a molecular method to identify the most prevalent race of Pgt, as a supplement for traditionally used host-specific methods. Amplified fragment length polymorphism (AFLP) was employed as a means of analyzing DNA polymorphisms in six common physiological races of Pgt in China and Ug99. In total, 64 pairs of primers were used for AFLP screening of race-specific molecular markers. One primer pair-namely, E7/M7 (5'-GACTGCGTACCAATTCG G-3'/5'-GATGAGTCCTGAGTAACGG-3')-yielded a unique band for the race 34MKG that was purified and cloned into the pGEM-T vector for sequencing. We then designed a new primer pairs (sequence-characterized amplified region marker) to amplify the 171-bp fragment and confirmed that the marker was highly specific for 34MKG. These results provide a new tool for monitoring different races of Pgt for improved control of wheat stem rust in China.


Assuntos
Resistência à Doença/genética , Doenças das Plantas/genética , Puccinia/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados/métodos , Basidiomycota/genética , China , Mapeamento Cromossômico/métodos , Repetições de Microssatélites/genética , Fenótipo , Doenças das Plantas/microbiologia , Polimorfismo Genético/genética , Puccinia/metabolismo , Triticum/genética , Triticum/microbiologia
6.
Plant Dis ; 104(8): 2082-2085, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32552283

RESUMO

Wheat stem rust caused by Puccinia graminis f. sp. tritici is an important wheat disease with sudden and devastating characteristics. The appearance and spread of new P. graminis f. sp. tritici races (Ug99, TKTTF, and TTTTF) have once again renewed the interest in the prevention and control of wheat stem rust. Fungicides can effectively control the epidemics of this disease in a short period of time. However, the fungal pathogen is prone to developing resistance. Therefore, we collected 89 isolates of P. graminis f. sp. tritici from four provinces in China and used the spore germination method to test the sensitivity of the isolates to fungicide triadimefon. Seven relatively triadimefon-sensitive isolates and six relatively triadimefon-resistant isolates were further tested for sensitivity to fungicides carbendazim, mancozeb, thiophanate-methyl, and kresoxim-methyl. The results showed that the mean concentration for 50% of maximal effect of the isolates to triadimefon was 16.14 mg·liter-1, and the mean resistance factor was 4.48. Only 29 isolates were resistant to triadimefon in which 27 isolates had low levels of resistance and 2 isolates had moderate levels of resistance. However, most of the 89 isolates had no resistance to triadimefon. There was a positive correlation between resistance to triadimefon and carbendazim, but there was no cross-resistance between triadimefon resistance with thiophanate-methyl or kresoxim-methyl resistance. This study provides valuable information for managing fungicide resistant isolates of P. graminis f. sp. tritici.


Assuntos
Basidiomycota , Fungicidas Industriais , China , Doenças das Plantas , Triazóis
7.
Int J Mol Sci ; 20(19)2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31581639

RESUMO

Wheat stem rust caused by Puccinia graminis f. sp. tritici (Pgt) had been a devastating foliar disease worldwide during the 20th century. With the emergence of Ug99 races, which are virulent to most stem rust resistance genes deployed in wheat varieties and advanced lines, stem rust has once again become a disease threatening global wheat production. Sr52, derived from Dasypyrum villosum and mapped to the long arm of 6V#3, is one of the few effective genes against Ug99 races. In this study, the wheat-D. villosum Robertsonian translocation T6AS·6V#3L, the only stock carrying Sr52 released to experimental and breeding programs so far, was crossed with a CS ph1b mutant to induce recombinants with shortened 6V#3L chromosome segments locating Sr52. Six independent homozygous recombinants with different segment sizes and breakpoints were developed and characterized using in situ hybridization and molecular markers analyses. Stem rust resistance evaluation showed that only three terminal recombinants (1381, 1380, and 1392) containing 8%, 22%, and 30% of the distal segment of 6V#3L, respectively, were resistant to stem rust. Thus, the gene Sr52 was mapped into 6V#3L bin FL 0.92-1.00. In addition, three molecular markers in the Sr52-located interval of 6V#3L were confirmed to be diagnostic markers for selection of Sr52 introgressed into common wheat. The newly developed small segment translocation lines with Sr52 and the identified molecular markers closely linked to Sr52 will be valuable for wheat disease breeding.


Assuntos
Basidiomycota , Mapeamento Cromossômico , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Recombinação Genética , Triticum/genética , Triticum/microbiologia , Pontos de Quebra do Cromossomo , Genes de Plantas , Marcadores Genéticos , Fenótipo
8.
J Craniofac Surg ; 29(2): e162-e167, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29303853

RESUMO

BACKGROUND: Patients' satisfaction is an increasingly important indicator for successful ear reconstruction surgeries. However, there is no scientifically sound patient-based outcome instrument in this field. This study aims at developing a patient-reported outcome measure for microtia reconstruction for investigating patients' satisfaction and perception of reconstructed ear and clinical researches. METHODS: The development of questionnaire included 3 stages. Traditional psychometric tests were used for analysis. At first stage, a preliminary version of the questionnaire was developed using qualitative methods, including interviews with 10 patients. At second stage, the questionnaire was field tested by survey of 76 patients. Redundant items were deleted; acceptability, reliability, and responsiveness were examined. At third stage, survey was conducted to another 94 patients with the shortened questionnaire to further evaluate the acceptability, reliability, and validity. RESULTS: A questionnaire of 12 items for microtia reconstruction was developed. Results demonstrated the instrument satisfied the current criteria. The acceptability (missing data <1%, largest endorsement frequencies <60%), reliability (Cronbach alphas >0.80, item-total correlations >0.7, interitem correlation <0.8), validity (scale intercorrelations r = 0.59, low correlations with age and sex) of the questionnaire. CONCLUSIONS: The questionnaire is an acceptable, reliable, and validated outcome measure for evaluation of ear reconstruction esthetic outcomes in microtia patients. It could be used for further comparison studies and effectiveness studies.


Assuntos
Microtia Congênita/cirurgia , Satisfação do Paciente , Procedimentos de Cirurgia Plástica , Inquéritos e Questionários , Adolescente , Adulto , Criança , Estética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Percepção , Psicometria , Reprodutibilidade dos Testes , Adulto Jovem
9.
Front Plant Sci ; 14: 1156936, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063217

RESUMO

Wheat stem rust is caused by Puccinia graminis f. sp. tritici. This major disease has been effectively controlled via resistance genes since the 1970s. The appearance and spread of new races of P. graminis f. sp. tritici (eg., Ug99, TKTTF, and TTRTF) have renewed the interest in identifying the resistance gene and breeding cultivars resistant to wheat stem rust. In this study, gene postulation, pedigree analysis, and molecular detection were used to determine the presence of stem rust resistance genes in 65 commercial wheat cultivars from Hebei Province. In addition, two predominant races 21C3CTHTM and 34MRGQM were used to evaluate the resistance of these cultivars at the adult-plant stage in 2021-2022. The results revealed that 6 Sr genes (namely, Sr5, Sr17, Sr24, Sr31, Sr32, Sr38, and SrTmp), either singly or in combination, were identified in 46 wheat cultivars. Overall, 37 wheat cultivars contained Sr31. Sr5 and Sr17 were present in 3 and 3 cultivars, respectively. Gao 5218 strong gluten, Jie 13-Ji 7369, and Kenong 1006 contained Sr24, Sr32, and Sr38, respectively. No wheat cultivar contained Sr25 and Sr26. In total, 50 (76.9%) wheat cultivars were resistant to all tested races of P. graminis f. sp. tritici in field test in 2021-2022. This study is important for breeding wheat cultivars with resistance to stem rust.

10.
Plast Reconstr Surg ; 150(1): 157e-167e, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35575865

RESUMO

BACKGROUND: Effective handling of auricular complications after the first stage of autologous cartilage microtia reconstruction remains one of the most demanding challenges for plastic surgeons. Here, the authors discuss relevant details for treatment of such complications in various conditions. METHODS: A total of 1739 microtia patients underwent the first stage of auricular reconstruction with autogenous costal cartilage between 2007 and 2019. Different complications occurred in 136 cases. The details of complications are described, and relevant tactics for appropriate prevention and treatment are introduced. RESULTS: Selective methods for the management of different complications in a prompt and effective manner after the first stage of ear reconstruction have been shown to salvage and maintain the contour of the reconstructed auricle to the maximum extent. CONCLUSION: Auricular complications can be well treated and prevented through careful preoperative preparation, meticulous intraoperative manipulation, and proper postoperative management. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


Assuntos
Microtia Congênita , Cartilagem Costal , Pavilhão Auricular , Procedimentos de Cirurgia Plástica , Cartilagem/transplante , Microtia Congênita/cirurgia , Cartilagem Costal/transplante , Pavilhão Auricular/cirurgia , Orelha Externa/cirurgia , Humanos , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/métodos
11.
Int J Pediatr Otorhinolaryngol ; 153: 111016, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34974275

RESUMO

OBJECT: For congenital microtia patients with a depressed mastoid area, it is unclear whether autologous fat grafting to fill the depressed area of the cheek will affect the survival of the subsequent grafted costal cartilage stent. An animal model was used for in vivo research to provide guidance for clinical applications. METHODS: Autologous costal cartilage was implanted in nude mice. Fat samples were collected at different time points and histological examination performed to analyze the activity of chondrocytes and the deposition of the chondrocyte matrix. RESULTS: This nude mouse fat transplantation model study showed that there were statistical differences in chondrocyte viability between the fat filling group and the control group, but there was no statistical difference in the effect on collagen content. CONCLUSION: Transplanting fat reduces the viability of chondrocytes, but has little effect on collagen matrix deposition.


Assuntos
Microtia Congênita , Cartilagem Costal , Tecido Adiposo , Animais , Condrócitos , Microtia Congênita/cirurgia , Cartilagem da Orelha , Orelha Externa , Humanos , Camundongos , Camundongos Nus , Stents
12.
PeerJ ; 10: e14118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262408

RESUMO

Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici (an obligate biotrophic pathogen) is a worldwide threat to wheat production that occurs over a wide geographic area in China. For monitoring genetic variation and virulence structure of Blumeria graminis f. sp. tritici in Liaoning, Heilongjiang, and Sichuan in 2015, 31 wheat lines with known Powdery mildew resistance genes and 2 EST-SSR markers were used to characterize the virulence and genetic diversity. Results indicated that 90% of all isolates were virulent on Pm3c, Pm3e, Pm3f, Pm4a, Pm5, Pm6 (Timgalen), Pm7, Pm16, Pm19, and Pm1 + 2 + 9 and 62.6% to 89.9% of isolates were virulent on Pm3a, Pm3b, Pm3d, Pm4b, Pm6 (Coker747), Pm8, Pm17, Pm20, Pm23, Pm30, Pm4 + 8, Pm5 + 6, Pm4b + mli, Pm2 + mld, Pm4 + 2X, Pm2 + 6. The Pm13 and PmXBD genes were effective against most collected isolates from Liaoning and Heilongjiang Provinces. Only Pm21 exhibited an immune infection response to all isolates. Furthermore, closely related isolates within each region were distinguished by cluster analyses using EST-SSR representing some gene exchanges and genetic relationships between the flora in Northeast China (Liaoning, Heilongjiang) and Sichuan. Only 45% of the isolates tested show a clear correlation between EST-SSR genetic polymorphisms and the frequency of virulence gene data. However, the EST-SSR polymorphism of isolated genes did not correspond to the virulence diversity of isolates in the single-gene lineage identification of hosts.


Assuntos
Ascomicetos , Ascomicetos/genética , Erysiphe/genética , Variação Genética/genética , Virulência/genética , Polimorfismo Genético
13.
Front Plant Sci ; 13: 1031611, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36507438

RESUMO

This is the first study reporting droplet digital PCR and quantitative real time PCR for detection of Tilletia caries (syn. T. tritici), which causes common bunt of wheat and leads to yield losses of 80% in many wheat growing areas worldwide. To establish an accurate, rapid and quantifiable detection method, we tested 100 inter simple sequence repeats (ISSR) primers and obtained a species-specific fragment (515 bp) generated by ISSR 827. Then, a specific 266 bp band for the sequence characterized amplified region (SCAR) marker was produced from T. caries. The detection limit reached 50 pg/µL. Based on the SCAR marker, we further developed a higher sensitivity of quantitative real time-polymerase chain reaction (qRT-PCR) with a detection limit of 2.4 fg/µL, and droplet digital PCR (ddPCR) with a detection limit of 0.24 fg/µL. Both methods greatly improved the detection sensitivity of T. caries, which will be contribute a lot for quickly and accurately detection of T. caries, which causes wheat common bunt.

14.
Polymers (Basel) ; 13(5)2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673625

RESUMO

3D printing technology is a versatile technology. The waste of 3D printed plastic products is a matter of concern because of its impact on the circular economy. In this paper, we discuss the current status and problems of 3D printing, different methods of 3D printing, and applications of 3D printing. This paper focuses on the recycling and degradation of different 3D printing materials. The degradation, although it can be done without pollution, has restrictions on the type of material and time. Degradation using ionic liquids can yield pure monomers but is only applicable to esters. The reprocessing recycling methods can re-utilize the excellent properties of 3D printed materials many times but are limited by the number of repetitions of 3D printed materials. Although each has its drawbacks, the great potential of the recycling of 3D printed waste plastics is successfully demonstrated with examples. Various recycling approaches provide the additional possibility of utilizing 3D printing waste to achieve more efficient circular application.

15.
PeerJ ; 9: e10580, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33614261

RESUMO

Wheat stem rust, caused by Puccinia graminis f. sp. tritici, (Pgt) is a devastating disease in wheat production. The disease has been effectively controlled since the 1970s due to the widespread use of the Sr31 resistance gene. However, Sr31 has lost its effectiveness following the emergence and spread of the Ug99 race variants. Therefore, there is an urgent global effort to identify new germplasm resources effective against those races. In this study, the resistance to Pgt of 95 wheat advance lines from Heilongjiang Province was evaluated using three predominant races of Pgt, 21C3CTTTM, 34C0MKGSM, and 34C3MTGQM, in China at the seedling and adult plant stage. The presence of 6 Sr genes (Sr2, Sr24, Sr25, Sr26, Sr31, and Sr38) was evaluated using linked molecular markers. The results showed that 86 (90.5%) wheat lines had plant stage resistance to all three races. Molecular marker analysis showed that 24 wheat lines likely carried Sr38, 15 wheat lines likely carried Sr2, 11 wheat lines likely carried Sr31, while none of the wheat lines carried Sr24, Sr25, or Sr26. Furthermore, six out of the 95 wheat lines tested carried both Sr2 and Sr38, three contained both Sr31 and Sr38, and two wheat lines contained both Sr2 and Sr31. Wheat lines with known Sr genes may be used as donor parents for further breeding programs to provide resistance to stem rust.

16.
Materials (Basel) ; 14(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34501198

RESUMO

The properties of the MoS2/Zr coatings can be significantly affected by the deposition temperature. In this study, the MoS2/Zr composite coatings were fabricated on the cemented carbide surface, utilizing the duplex deposition technology at various deposition temperatures. The effects of deposition temperature on the mechanical and friction properties of the MoS2/Zr coatings were systematically studied. Results exhibited that as the deposition temperature increased, the adhesion force increased first and then decreased, and the coating thickness and micro-hardness gradually increased. Dry sliding tests against a hardened steel ring showed that the tribological behaviors and wear mechanisms of the MoS2/Zr coatings varied with deposition temperature, which were due to the changing mechanical properties of coatings caused by the temperature. The coatings deposited at a temperature of 180 °C and 200 °C possessed preferable comprehensive mechanical and tribological properties.

17.
RSC Adv ; 11(4): 2010-2019, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35424197

RESUMO

The gas diffusion layer (GDL) is an important component in the proton exchange membrane fuel cell (PEMFC), and the main function of GDL is to transfer water and gas. This paper explores the effect of the gradient hydrophobicity of GDL on the proton exchange membrane fuel cell (PEMFC). The gradient GDL design uses two microporous layers (MPL). First, polytetrafluoroethylene (PTFE) : carbon black in MPL near the carbon paper side was fixed at 3 : 7, and then the content of PTFE : carbon black in MPL near the catalyst layer (CL) was set to 3 : 7, 2 : 8 and 1 : 9. Second, the fixed PTFE : carbon black in MPL near the carbon paper side was 2 : 8, and the PTFE : carbon black in MPL near CL was 2 : 8 and 1 : 9. We found that, when near the carbon paper side and PTFE : carbon black = 3 : 7, GDL can obtain good cell performance through gradient hydrophobic treatment. Moreover, when near the carbon paper side and PTFE : carbon black = 2 : 8, the cell performance did not change much after GDL gradient hydrophobic treatment. We found that when GDL is subjected to a gradient hydrophobic treatment, the content of PTFE and carbon black must be rationally allocated to obtain good water management capabilities.

18.
PeerJ ; 9: e10425, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33510966

RESUMO

Wheat powdery mildew, caused by the biotrophic fungus Blumeria graminis f. sp. tritici (Bgt), is a serious disease of wheat worldwide that can cause significant yield losses. Growing resistant cultivars is the most cost-effective and eco-soundly strategy to manage the disease. Therefore, a high breeding priority is to identify genes that can be readily used either singly or in combination for effective resistance to powdery mildew and also in combination with genes for resistance to other diseases. Yunnan Province, with complex and diverse ecological environments and climates, is one of the main wheat growing regions in China. This region provides initial inoculum for starting epidemics of wheat powdery mildew in the region and other regions and thus, plays a key role in the regional and large-scale epidemics of the disease throughout China. The objectives of this study were to evaluate seedling resistance of 69 main wheat cultivars to powdery mildew and to determine the presence of resistance genes Pm3, Pm8, Pm13, Pm16, and Pm21in these cultivars using gene specific DNA markers. Evaluation of 69 wheat cultivars with six Bgt isolates showed that only four cultivars were resistant to all tested isolates, indicating that the overall level of powdery mildew resistance of Yunnan wheat cultivars is inadequate. The molecular marker results showed that 27 cultivars likely have at least one of these genes. Six cultivars were found likely to have Pm3,18 likely to have Pm8,5 likely to have Pm16,and 3 likely to have Pm21. No cultivar was found to carry Pm13. The information on the presence of the Pmresistance genes in Yunnan wheat cultivars can be used in future wheat disease breeding programs. In particular, cultivars carrying Pm21, which is effective against all Bgtraces in China, should be pyramided with other effective genes to developing new cultivars with durable resistance to powdery mildew.

19.
Front Plant Sci ; 12: 751398, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721479

RESUMO

Wheat stem (or black) rust is one of the most devastating fungal diseases, threatening global wheat production. Identification, mapping, and deployment of effective resistance genes are critical to addressing this challenge. In this study, we mapped and characterized one stem rust resistance (Sr) gene from the tetraploid durum wheat variety Kronos (temporary designation SrKN). This gene was mapped on the long arm of chromosome 2B and confers resistance to multiple virulent Pgt races, such as TRTTF and BCCBC. Using a large mapping population (3,366 gametes), we mapped SrKN within a 0.29 cM region flanked by the sequenced-based markers pku4856F2R2 and pku4917F3R3, which corresponds to 5.6- and 7.2-Mb regions in the Svevo and Chinese Spring reference genomes, respectively. Both regions include a cluster of nucleotide binding leucine-repeat (NLR) genes that likely includes the candidate gene. An allelism test failed to detect recombination between SrKN and the previously mapped Sr9e gene. This result, together with the similar seedling resistance responses and resistance profiles, suggested that SrKN and Sr9e may represent the same gene. We introgressed SrKN into common wheat and developed completely linked markers to accelerate its deployment in the wheat breeding programs. SrKN can be a valuable component of transgenic cassettes or gene pyramids that includes multiple resistance genes to control this devastating disease.

20.
EClinicalMedicine ; 31: 100668, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33385126

RESUMO

BACKGROUND: Gallbladder drainage plays a key role in the management of acute cholecystitis (AC) patients. Percutaneous transhepatic gallbladder drainage (PTGBD) is commonly used while endoscopic naso-gallbladder drainage (ENGBD) serves as an alternative. METHODS: A single center, prospective randomized controlled trial was performed. Eligible AC patients were randomly assigned to ENGBD or PTGBD group. Randomization was a computer-generated list with 1:1 allocation. All patients received cholecystectomy 2-3 months after drainage. The primary endpoint was abdominal pain score, and the intention-to-treat population was analyzed. (ClinicalTrials.gov: NCT03701464). FINDINGS: Between Oct 1, 2018 and Feb 29, 2020, 22 out of 61 consecutive AC patients were enrolled in the final analysis. The mean abdominal pain scores before drainage, and at 24, 48, and 72 h after drainage in ENGBD were 6.9 ± 1.1, 4.3 ± 1.2, 2.2 ± 0.8 and 1.5 ± 0.5, respectively, while those of PTGBD were 7.4 ± 1.2, 6.2 ± 1.2, 5.3 ± 1.0 and 3.7 ± 0.9; and the mean gallbladder area tenderness scores were 8.4 ± 1.2, 5.7 ± 0.9, 3.5 ± 0.7, 2.5 ± 0.5 for ENGBD and 8.6 ± 0.9, 7.3 ± 1.0, 7.4 ± 0.5, 4.8 ± 0.9 for PTGBD. The mean abdominal pain and gallbladder area tenderness scores of the ENGBD significantly decreased than the PTGBD (group × time interaction P<0.001, respectively). ENGBD group presented lower post-operative hemorrhage and abdominal drainage tube placement rates (median (IQR) 15[5-20] vs 40[20-70]ml, 3vs9, P = 0.03), and pathological grade and lymphocyte count were observed (P = 0.004) between groups. No adverse events were observed in 3 months follow-up. INTERPRETATION: Compared to PTGBD, ENGBD group presented less pain, better gallbladder pathological grades and less surgical difficulties during cholecystectomy procedures. FUNDING: National Natural Science Foundation of China (82060551).

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