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1.
iScience ; 27(4): 109429, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38562522

RESUMO

Originally derived from graphite, high-quality single-layer graphene is an excellent anti-wear and -friction additive in metal matrix. Here, the tribological performance of 3 different commercialized graphene derivatives (e.g., graphene oxide [GO], reduced graphene oxide [RGO], and graphene nanoplatelet [GNP]) as additives in a Cu matrix, were investigated from an industrial perspective. To increase the interaction of graphene derivatives with Cu particles, and addressing the aggregation problem of the graphene derivatives, different binders (polyvinyl alcohol [PVA] and cellulose nanocrystals [CNC]) were introduced into the system. Benefiting from such a strategy, a uniform distribution of the graphene derivatives in Cu matrix was achieved with graphene loading up to 5 wt %. After high-temperature sintering, the graphene is preserved and well distributed in the Cu matrix. It was found that the GNP-containing sample shows the most stable friction coefficient behavior. However, GO and RGO also improve the tribological performance of Cu under different circumstances.

2.
NanoImpact ; 33: 100499, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38369193

RESUMO

Graphene is a 2D-material with many useful properties such as flexibility, elasticity, and conductivity among others. Graphene could therefore become a material used in many occupational fields in the future, which can give rise to occupational exposure. Today, exposure is unknown, due to the lack of efficient measuring techniques for occupational exposure to graphene. Readily available screening techniques for air sampling and -analysis are either nonspecific or nonquantitative. Quantifying materials from the broad graphene family by an easy-to-use method is important for the large-scale industrial application of graphene, especially when for the safety of working environment. Graphene consists primarily of elemental carbon, and the present study evaluates the organic carbon/elemental carbon (OC/EC)-technique for exposure assessment. The purpose of this work is to evaluate the OC/EC analysis technique as an efficient and easy-to-use method for quantification of occupational exposure to graphene. Methods that can identify graphene would be preferable for screening, but they are time consuming and semi-quantitative and therefore not suited for quantitative work environment assessments. The OC/EC-technique is a thermal optical analysis (TOA), that quantitively determines the amount of and distinguishes between two different types of carbon, organic and elemental. The technique is standardised, well-established and among other things used for diesel exposure measurements (ref standard). OC/EC could therefore be a feasible measuring technique to quantitively determine occupational exposure to graphene. The present evaluation of the technique provides an analytical method that works quantitatively for graphene, graphene oxide and reduced graphene oxide. Interestingly, the TOA technique makes it possible to distinguish between the three graphene forms used in this study. The technique was tested in an industrial setting and the outcome suggests that the technique is an efficient monitoring technique to be used in combination with characterisation techniques like for example Raman spectroscopy, scanning electron microscopy and atomic force microscopy.


Assuntos
Grafite , Exposição Ocupacional , Monitoramento Ambiental/métodos , Exposição Ocupacional/análise , Carbono/análise
3.
J Colloid Interface Sci ; 660: 974-988, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38286057

RESUMO

Metal-organic frameworks (MOFs) have been regarded as a potential candidate with great application prospects in the field of gas sensing. Although plenty of previous efforts have been made to improve the sensitivity of MOF-based nanocomposites, it is still a great challenge to realize ultrafast and high selectivity to typical flammable gases in a wide range. Herein, porous xPd-NPs@ZnO were prepared by optimized heat treatment, which maintained the controllable morphology and high specific surface area of 471.08 m2g-1. The coupling effects of photoexcitation and thermal excitation on the gas-sensing properties of nanocomposites were systematically studied. An ultrafast high response of 88.37 % towards 200 ppm H2 was realized within 1.2 s by 5.0Pd-NPs@ZnO under UV photoexcitation. All xPd-NPs@ZnO exhibited favorable linearity over an extremely wide range (0.2-4000 ppm H2) of experimental tests, indicating the great potential in quantitative detection. The photoexcited carriers enabled the nanocomposites a considerable response at lower operating temperatures, which made diverse applications of the sensors. The mechanisms of high sensing performances and the photoexcitation enhancement were systematically explained by DFT calculations. This work provides a solid experimental foundation and theoretical basis for the design of controllable porous materials and novel photoexcited gas detection.

4.
Adv Sci (Weinh) ; 11(9): e2307067, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38095537

RESUMO

Pressure-induced swelling has been reported earlier for several hydrophilic layered materials. MXene Ti3C2Tx is also a hydrophilic layered material composed by 2D sheets but so far pressure-induced swelling is reported for this material only under conditions of shear stress at MPa pressures. Here, high-pressure experiments are performed with MXenes prepared by two methods known to provide "clay-like" materials. MXene synthesized by etching MAX phase with HCl+LiF demonstrates the effect of pressure-induced swelling at 0.2 GPa with the insertion of additional water layer. The transition is incomplete with two swollen phases (ambient with d(001) = 16.7Å and pressure-induced with d(001) = 19.2Å at 0.2 GPa) co-existing up to the pressure point of water solidification. Therefore, the swelling transition corresponds to change from two-layer water intercalation (2L-phase) to a never previously observed three-layer water intercalation (3L-phase) of MXene. Experiments with MXene prepared by LiCl+HF etching have not revealed pressure-induced swelling in liquid water. Both MXenes also show no anomalous compressibility in liquid methanol. The presence of pressure-induced swelling only in one of the MXenes indicates that the HCl+LiF synthesis method is likely to result in higher abundance of hydrophilic functional groups terminating 2D titanium carbide.

5.
Tree Physiol ; 44(1)2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-37847604

RESUMO

Root pruning hinders the absorption and utilization of nutrients and water by seedlings in the short term. Arbuscular mycorrhizal fungi (AMF) are an important source of nutrient and water for seedlings except for the root system. However, the mechanism by which AMF affect the physiological growth of seedlings after root pruning has rarely been studied. In this study, a pot experiment was conducted through a three-compartment partition system to clarify the effects of Funneliformis mosseae (F. mosseae) strain BGC XJ07A on the physiological growth of root-pruned Robinia pseudoacacia seedlings. Five root pruning treatments (zero, one-fifth, one-fourth, one-third and one-half of the taproot length were removed) were applied to noninoculated seedlings and those inoculated with F. mosseae. The results showed that the presence of F. mosseae significantly increased the shoot and root biomasses, leaf photosynthetic rate, stomatal conductance and transpiration rate. The root projected area, root surface area, average root diameter, root density, root volume and number of root tips of the inoculated seedlings were higher than those without inoculation in all root pruning treatments. The root cytokinin, gibberellins and indole-3-acetic acid concentrations, but root abscisic acid concentration, were higher than those measured in the absence of inoculation in all root pruning treatments. Moreover, the changes in the root endogenous hormone concentrations of the seedlings were closely related to the root morphological development and seedling biomass. The AMF increased the soil available nitrogen, soil available phosphorus, soil available potassium and soil organic matter concentrations compared with the noninoculated treatment. These results indicate that AMF can alleviate the adverse effects of root pruning on the physiological growth of R. pseudoacacia and soil properties, and can provide a basis for AMF application to forest cultivation and the sustainable development of forest ecosystems.


Assuntos
Fungos , Micorrizas , Robinia , Micorrizas/fisiologia , Plântula , Ecossistema , Fotossíntese , Água , Solo
6.
Plant Dis ; 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38127631

RESUMO

Papaya (Carica papaya L.) belonging to the family Caricaceae is well known for its economic and nutritional value. Anthraconse caused by Colletotrichum spp. is a main postharvest disease of papaya fruit during storage (Cia et al., 2007). In July 2022, papaya fruits with anthracnose symptoms were collected in Changjiang County (108.996180E, 19.246560N), Hainan Province, China. The disease incidence of fruit rot reached 6.3%. Initial symptoms appeared as the watery lesions with tiny black spots, turning to dark brown, sunken necrotic lesions. The diseased tissues were cut into 18 pieces (5×5 mm) from 6 papaya fruits, disinfected with 2% sodium hypochlorite for 60 s, and rinsed three times with sterilized water. The pieces were air-dried and then placed on potato dextrose agar (PDA) at 28 ℃ for five days. Twelve isolates with similar morphology were obtained from 18 tissue pieces. Three isolates (FMG01, FMG02 and FMG03) were selected for morphological identification, molecular identification, and pathogenicity tests. Colonies were initially white, then gradually became dark grey on PDA. The ascospores were hyaline, fusoid, rounded at both ends, 37.43-84.32 (55.79±7.61) µm × 4.30-6.55 (5.36±0.60) µm (n=50). The conidia were hyaline, unicellular, long cylindrical, bluntly rounded at both ends, 11.59-25.54 (18.62±2.33) µm × 5.12-8.44 (7.19±0.62) µm (n=100). Appressoria were gray to dark brown, irregular, pyriform, or ovoid, 10.14-21.40 (13.81±2.25) µm × 6.05-11.85 (9.16±1.29) µm (n=50). Morphological features are similar to Colletotrichum gigasporum identified and described by Rakotoniriana et al (Rakotoniriana et al., 2013). In order to accurately identify the isolates, the internal transcribed spacer region (ITS) of the rDNA, the glyceraldehyde-3-phosphate dehydrogenase (GAPDH), the partial actin (ACT), the beta-tubulin (TUB2) and the calmodulin (CAL) genes were amplified and sequenced (Cannon et al., 2012). The nucleotide sequences were deposited into GenBank (accession numbers, ITS: OR017446 to OR017448, GAPDH: OR042810 to OR042812, ACT: OR042813 to OR042815, TUB2: OR042816 to OR042818, CAL: OR042819 to OR042821). Based on the BLASTn analysis, these sequences were more than 99% with the reference strain CBS 125476 of C. gigasporum sequences (ITS: MH863698, GAPDH: KF687833, ACT: KF687790, TUB2: KF687875, CAL: KF687814), respectively. The results of the multilocal phylogenetic analysis showed that the three isolates were C. gigasporum based on the Maximum Likelihood and Bayesian inference method. The pathogenicity test was performed by wounded with a sterile needle on the surface-sterilized papaya fruits. The mycelial discs (5 mm diameter) of three isolates were inoculated orderly on the same fruit, and the same inoculation was applied to non-wound papaya fruits. The control group were inoculated with sterilized PDA. Each treatment carried out with 9 fruits. The inoculated fruits were placed at 28 ℃ in plastic preservation boxes (32×22×11 cm) with sterilized distilled water to maintain high humidity. After 5 d of inoculation, typical anthracnose symptoms were observed on wound fruits and the non-wound fruits developed symptoms at 7 dpi, control fruits were symptomless. The fungi re-isolated from the inoculated fruits lesions after inoculation and identified by morphological characterization and molecular identification, fulfilling Koch's postulates. C. gigasporum has been reported causing leaf rot of Dalbergia odorifera in China (Wan et al., 2018). To our knowledge, this is the first report of anthracnose fruit rot of papaya caused by C. gigasporum in China.

7.
Plant Dis ; 2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37807094

RESUMO

Dalbergia odorifera (Family: Fabaceae) is a national second-grade protected tree in China with high medicinal and economic value (Zhao et al., 2020). In July, 2022, a leaves spot disease on D. odorifera with typical anthracnose symptoms was observed in plantations in Haikou (110.319153°E, 19.072900°N), Dongfang (108.630297°E, 19.103838°N) and Qiongzhong (109.704460°E, 19.088440°N), Hainan Province, China. Disease incidence was 7.5% (n = 50 plants). Early symptoms of infected leaves were small and round dark brown spots, which developed into larger irregular necrotic lesions and leaves withered. Leaf tissues (5×5 mm) at the disease-health junction of spots from 19 leaves were sterilized with 2.5% sodium hypochlorite for 1 min, and rinsed with sterile distilled water three times. These sterilized tissues were placed on potato dextrose agar (PDA) and incubated at 28 ℃ for 5 d. 7 strains of fungi with similar morphology were isolated, and 3 single-hyphal isolates (HHL01, HHL02 and HHL03) from each location were selected for further study. Colonies on PDA were fluffy orange-yellow mycelium. Conidia were aseptate, cylindrical, smooth-walled, straight, hyaline with both ends bluntly rounded, 11.82 to 15.77 × 3.87 to 6.71 µm (n = 100; average = 13.75 × 5.52 µm). Appressoria formed on slides, measured 5.54 to 10.64 × 4.19 to 7.41 µm (n = 30; average = 8.06 × 5.97 µm) were brown to black, elliptical to irregular. For molecular biological identification, the genomic DNA of three isolates was extracted by fungal genomic DNA extraction kit (Tiangen Biotech (Beijing) Co., Ltd.). The partial sequences of internal transcribed spacer region (ITS; ITS1/ITS4), glyceraldehyde-3-phosphate dehydrogenase (GAPDH; GDF1/GDR1), actin (ACT; ACT512F/ACT783R), ß-tubulin (TUB2; TI/Bt2b) and calmodulin (CAL; CL1C/CL2C) were amplified and sequenced by Sangon Biotech (Shanghai) Co., Ltd (Carbone and Kohn, 1999; Weir et al., 2012). The sequences were deposited as GenBank Accession Nos. OR018110-OR018112 (ITS); OR050529-OR050537 (GAPDH, ACT and CAL) and OR192168-OR192170 (TUB). BLASTn results showed these sequences were more than 99% identity with the strain of C. karstii CORCK1 (GenBank Accession Nos. HM585406, HM585387, HM581991, HM585424 and HM582010, respectively). Multi-locus phylogenetic tree of Colletotrichum spp. showed that those three isolates were sister to C. karstii based on the maximum likelihood and bayesian inference methods. To verify pathogenicity, 2 mL spore suspension (1 × 106conidia/ml) of the isolates was sprayed on each leaves of 1-year-old D. odorifera plants, and sterile distilled water was similarly sprayed on other leaves as a negative control. The plants were incubated in a greenhouse under 90% ± 5% RH at 28 °C. Light brown small round necrotic patches developed 3 days after inoculation, while the control was asymptomatic. Photographs were taken on the fifth day after inoculation. The fungi were re-isolated from the diseased leaves and identified by morphological characterization and molecular identification, fulfilling Koch's postulates. C. karstii has been reported causing leaf rot of Carissa grandiflora in Spain (Garcia-Lopez et al., 2021), and anthracnose caused by C.tropicale was reported on D. odorifera (Yi et al., 2023). To our knowledge, this is the first report of Dalbergia odorifera leaf spot disease caused by Colletotrichum karstii. This finding provides an important basis for further research on the control of the disease.

8.
ACS Appl Mater Interfaces ; 15(32): 38857-38866, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37550051

RESUMO

Although two-dimensional nanosheets like graphene could be ideal atomic coatings to prevent corrosion, it is still controversial whether they are actually effective due to the presence of parasitic effects such as galvanic corrosion. Here, we reported a reduced graphene oxide (RGO) coating strategy to protect sintered Cu metal powders from corrosion by addressing the common galvanic corrosion issue of graphene. A layer of silane molecules, namely, (3-aminopropyl)triethoxysilane (APTES), is deposited between the surface of Cu particles and the graphene oxide (GO), acting as a primer to enhance adhesion and as an insulating interlayer to prevent the direct contact of the Cu with conductive RGO, mitigating the galvanic corrosion. Due to this core-shell coating, the RGO uniformly distributes in the Cu matrix after sintering, avoiding aggregation of RGO, which takes place in conventional GO-Cu composites. The dual coating of GO and silane results in bulk samples with improved anticorrosion properties, as demonstrated by galvanostatic polarization tests using Tafel analysis. Our development not only provides an efficient synthesis method to controllably coat GO on the surface of Cu but also suggests an alternative strategy to avoid the galvanic corrosion effect of graphene to improve the anticorrosion performance of metal.

9.
Nat Commun ; 14(1): 5251, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37640698

RESUMO

Operando monitoring of complex physical and chemical activities inside rechargeable lithium-ion batteries during thermal runaway is critical to understanding thermal runaway mechanisms and giving early warning of safety-related failure. However, most existing sensors cannot survive during such extremely hazardous thermal runaway processes (temperature up to 500 °C accompanied by fire and explosion). To address this, we develop a compact and multifunctional optical fiber sensor (12 mm in length and 125 µm in diameter) capable of insertion into commercial 18650 cells to continuously monitor internal temperature and pressure effects during cell thermal runaway. We observe a stable and reproducible correlation between the cell thermal runaway and the optical response. The sensor's signal shows two internal pressure peaks corresponding to safety venting and initiation of thermal runaway. Further analysis reveals that a scalable solution for predicting imminent thermal runaway is the detection of the abrupt turning range of the differential curves of cell temperature and pressure, which corresponds to an internal transformation between the cell reversible and irreversible reactions. By raising an alert even before safety venting, this new operando measurement tool can provide crucial capabilities in cell safety assessment and warning of thermal runaway.

11.
J Colloid Interface Sci ; 645: 297-305, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37150003

RESUMO

Supercapacitors are attracting extensive attention in energy storage fields thanks to their high safety, cost-effectiveness, and environmental friendliness. The carbon materials, especially for the porous carbon materials derived from renewable biomass materials, are important electrode materials with cost-effective feature for supercapacitors. However, the inferior ionic conductivity of biomass materials inhibits their electrochemical performance in energy storage devices. Herein, an immiscible liquid-mediated method is provided to improve the ionic conductivity of silk-derived nitrogen-doped porous carbon (NPC) electrodes. Natural Bombyx mori (silkworm) silk is used as a carbon source for the preparation of electrode of supercapacitor. Further introducing immiscible organic liquid into the NPCs promotes the ion transport in the inner pores of the electrodes. With the assistance of organic liquid, the supercapacitor presents a specific capacitance of 565.3 F g-1 at a current density of 1 A g-1. The supercapacitor shows the maximum specific energy and power density of 26.2 Wh kg-1 and 263.9 W kg-1, and holds a capacitance retention of approximately 93.3% after 10 000 cycles. This work provides a facile method for the rational design of carbon material derived from biomass material to fabricate electrode with high ionic conductivity, and the strategy will be extendable to other biomass materials for a wide range of applications.

12.
Plant Dis ; 2023 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-37005506

RESUMO

Mango (Mangifera indica L.), belongs to the family Anacardiacea, and is one of the most popular tropical fruits in the world. Stem-end rot is a major postharvest disease of mango fruit, causing severe losses during storage in China (Chen et al., 2015). In July 2021, the mango fruits harvested from Baise Municipal National Agricultural Science and Technology Park (23.683568 N, 106.986325 E) of Guangxi province in China developed stem-end rot during storage. The disease incidence reached ca. 8.3%. The initial symptoms appeared as light brown lesions surrounding the peduncle, which quickly expanded becoming large dark-brown lesions. Small pieces of epidermis (5 mm × 5 mm) from 8 typical diseased friuts were cut from the edges of lesions surface-sterilized with 2% sodium hypochlorite and rinsed with sterile distilled water. The tissue was plated on potato dextrose agar (PDA) and incubated at 28 ℃ in the dark for 3 days. Fifteen, similarcolonies were isolated from the symptomatic tissue. The representative isolates DF-1, DF-2 and DF-3 were selected for morphological characterization, molecular identification, and pathogenicity testing. The colonies were circular with fluffy aerial mycelium, initially white turning to smoke-gray from the center in upper side and greenish black in reverse side, covering the 90 mm diameter Petri dish after 4 days of incubation on PDA at 28 ℃ in dark. Pycnidia were produced on the surface of the colony after 30 days. Conidia were fusiform, aseptate, hyaline, thin-walled with granular contents, apex sub-obtuse, base subtruncate to bluntly rounded, 14.0-20.3 (16.8±1.6) µm × 3.1-7.2 (5.1±0.9) µm (n=50). The sexual stage was absent. Based on morphology, isolates were preliminarily identified as Botryosphaeria speices. To accurately identify the pathogen, genomic DNA was extracted from the mycelium of the three isolates DF-1, DF-2 and DF-3. The internal transcribed spacer of rDNA region (ITS), elongation factor 1-alpha (EF-1α) and beta-tubulin gene (TUB) genes were amplified using primers ITS1/ITS4, EF1-728F/EF1-986R and Bt2a/Bt2b, respectively (Slippers et al., 2004). The nucleotide sequences were all deposited in GenBank (ITS: OP729176-OP729178 EF-1α: OP758194-OP758196 and TUB: OP758197-OP758199). Based on the BLASTn analysis, the ITS, EF1-α and TUB sequences of three isolates were 100%, 99% and 99% similar to the Botryosphaeria fabicerciana MFLUCC 10-0098 sequences (ITS: JX646789, EF-1α: JX646854 and TUB: JX646839). Multi-locus phylogenetic analyses (ITS, EF-1α and TUB) showed that the isolate DF-1, DF-2 and DF-3 were clustered within Botryosphaeria fabicerciana clade based on the maximum likelihood , Bayesian inference, and maximum parsimony methods. The pathogenicity test was performed by placing discs mycelium around the peduncle of mature mango fruits by pin-prick method. Each treatment carried out with 12 fruits. The inoculated fruits were placed in plastic boxes at 28 ℃ with three replicates. Three days after inoculation, typical symptoms of stem-end rot were observed. The control fruits were inoculated with sterile PDA discs, and remained symptomless. The same fungus was re-isolated from the symptomatic tissue to complete Koch's postulate. Botryosphaeria fabicerciana (basionym: Fusicoccum fabicercianum) was first reported as pathogen causing senescent twig of Eucalyptus spp. in China (Chen et al., 2011; Phillips et al., 2013). To our knowledge, this is the first report of Botryosphaeria fabicerciana causing stem-end rot of Mangifera indica in China.

13.
Plant Dis ; 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081633

RESUMO

Terminalia catappa belonging to the family Combretaceae, spreads in tropical and subtropical coastal areas. It mainly serves as shading and decorative tree (Anand et al, 2015). It is planted as roadside tree in Southern China. A leaf spot disease of T. catappa was observed at Wencheng Town (110.805323°E, 19.524567°N), Wenchang City, Hainan province, China in June, 2022. The disease incidence of leaves reached 10%. The occurrence of this leaf spot would reduce the ornamental value of T. catappa. The early symptoms of infected leaves were small, round, dark brown spots surrounded by irregular light halos, developing to larger irregular necrotic lesions and leaves withered. Twelve diseased leaves were collected from three survey trees. Symptomatic leaf samples were collected and cut into small pieces (3×3 mm). The pieces were surface sterilized with 2.5% sodium hypochlorite for 1 min, rinsed with sterile distilled water three times, placed on potato dextrose agar (PDA) medium and incubated at 28 ℃ in the dark for 3 days. Three hyphal tip isolates (DYLR-1, DYLR-2 and DYLR-3) were cultured on PDA. Colonies on PDA reached the edge of the 90 mm plates after 3 d and had fluffy mycelia with an uneven margin, initially creamy white, becoming light grey (5 d) to mouse grey (10 d) at the surface with the black globular cavity. To induce sporulation, the isolates were transferred to 2% water agar media with sterilised pine needles placed on the surface of the media. Conidia was hyaline, unicellular, thin-walled, smooth with granular contents, aseptate, narrowly fusiform, base subtruncate to bluntly rounded, 11.1 to 16.7 (14.5±1.4) × 4.6 to 7.6 (6.2±0.7) µm (n=50). Spermatia was hyaline, unicellular, aseptate, allantoid to rod-shaped, 3.2 to 6.9 (5.1±0.9) µm × 2.0 to 3.8 (2.5±0.4) µm (n=50). Pathogenicity tests were performed both in vitro and in vivo, and replicated twice. All three isolates were used for pathogenicity tests, with 18 detached leaves used for pathogenicity tests in vitro and 3 seedlings used for pathogenicity tests in vivo. A 5-mm-diameter agar plug containing mycelia were placed on the leaves both without and with wound. Sterile PDA plugs were used as controls. The leaves were moisturized with a clear plastic bag for 24 hours in a greenhouse under 90% ± 5% RH at 25 ℃. Brown spot symptoms were observed at 1 day post-inoculation (dpi) in vitro and 3 dpi in vivo. The same strains were reisolated from lesions of inoculated leaves. Control plants were symptomless. For molecular identification, internal transcribed spacer region and intervening 5.8S nrRNA gene (ITS; ITS1/ITS4 primers; White et al. 1990), translation elongation factor 1-alpha gene (tef1-α; EF1-728F/EF1-986R primers; Carbone and Kohn 1999), beta-tubulin gene (tub2; Bt2a/Bt2b primers; Glass and Donaldson 1995) and DNA directed RNA polymerase II second largest subunit gene (rpb2; RPB2bot6F/RPB2bot7R; Sakalidis et al. 2011) regions were PCR amplified from genomic DNA. The sequences (GenBank accessions numbers: OP435357 to OP435359 of ITS; OP535354 to OP535356 of tef1-α; OP535351 to OP535353 of tub2; OP535348 to OP535350 of rpb2) had 100%, 99.7%, 100%, 100% similar to the type strain of Neofusicoccum sinoeucalypti CERC2005 (GenBank accessions numbers: KX278061, KX278166, KX278270 and KX278290), respectively. Multi-locus phylogenetic tree (ITS, tef1-α, tub2 and rpb2) of Neofusicoccum spp. (Zhang et al. 2021) showed that those three isolates were sister to N. sinoeucalypti based on the maximum likelihood and bayesian inference methods. N. sinoeucalypti was first reported pathogen causing from Eucalyptus plantations and adjacent plants in China (Li et al. 2018). To our knowledge, this is the first report of Neofusicoccum sinoeucalypti causing leaf spot disease on Terminalia catappa in China. Neofusicoccum species, commonly cause diseases in woody plants worldwide, and identification of this pathogen is important for effective disease management and control.

14.
Chem Commun (Camb) ; 59(18): 2571-2583, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36749576

RESUMO

Energy storage devices are important components in portable electronics, electric vehicles, and the electrical distribution grid. Batteries and supercapacitors have achieved great success as the spearhead of electrochemical energy storage devices, but need to be further developed in order to meet the ever-increasing energy demands, especially attaining higher power and energy density, and longer cycling life. Rational design of electrode materials plays a critical role in developing energy storage systems with higher performance. Graphene, the well-known 2D allotrope of carbon, with a unique structure and excellent properties has been considered a "magic" material with its high energy storage capability, which can not only aid in addressing the issues of the state-of-the-art lithium-ion batteries and supercapacitors, but also be crucial in the so-called post Li-ion battery era covering different technologies, e.g., sodium ion batteries, lithium-sulfur batteries, structural batteries, and hybrid supercapacitors. In this feature article, we provide a comprehensive overview of the strategies developed in our research to create graphene-based composite electrodes with better ionic conductivity, electron mobility, specific surface area, mechanical properties, and device performance than state-of-the-art electrodes. We summarize the strategies of structure manipulation and surface modification with specific focus on tackling the existing challenges in electrodes for batteries and supercapacitors by exploiting the unique properties of graphene-related materials.

15.
Front Psychiatry ; 13: 997174, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36440399

RESUMO

Objective: To investigate the adaptability of Comprehensive Behavioral Intervention for Tics (CBIT) for a Chinese population, and evaluate the efficacy of combined CBIT and pharmacotherapy (CBIT + PT) compared to CBIT or pharmacotherapy (PT) alone for reducing tics and for improving the quality of life (QoL) in a sample of Chinese children with chronic tic disorders (CTD) and Tourette syndrome (TS). Materials and methods: In this 10-week randomized controlled pilot trial, 37 outpatients aged between 6 and 16 years affected by TS and CTD were randomly assigned to receive CBIT (n = 22) or PT alone (n = 15). Considering the feasibility, the patients allocated to the CBIT treatment group could further choose whether to simultaneously take medicine voluntarily, resulting in a CBIT alone group (n = 12) and a CBIT + PT group (n = 10). Results: At baseline, no significant difference was found between the three groups in the demographic and clinical characteristics (p > 0.05). All three groups showed a significant reduction in tic severity after treatment assessed by the Yale Global Tic Severity Scale (YGTSS) severity score [F (2,33) = 35.05, p < 0.001, η p 2 = 0.51], the score of the Clinical Global Impression scale for Improvement (CGI-I) [F (1,34) = 13.87, p = 0.001, η p 2 = 0.29], and YGTSS impairment score [F (2,33) = 31.71, p < 0.001, η p 2 = 0.48]. Significant interactions were found between the time-point and group in emotional functioning [F (2,29) = 4.39, p = 0.02, η p 2 = 0.23], psychosocial functioning [F (2,29) = 5.93, p = 0.007, η p 2 = 0.29], and total QoL score [F (1,34) = 3.72, p = 0.04, η p 2 = 0.20] of Pediatric Quality of Life Inventory (PedsQL 4.0) for children suggesting a significantly larger improvement in emotional functioning, psychosocial functioning, and total QoL score of the life quality in the CBIT group for children self-report. PedsQL for proxy report only showed a significant main effect of time-point in physical functioning [F (1,33) = 8.35, p = 0.01, η p 2 = 0.2], emotional functioning [F (1,33) = 10.75, p = 0.002, η p 2 = 0.25], psychosocial functioning [F (1,34) = 11.38, p = 0.002, η p 2 = 0.26], and total Qol score [F (1,34) = 13.21, p = 0.001, η p 2 = 0.29]. Conclusion: CBIT is probably effective in reducing tic severity in Chinese children with tic disorders. CBIT + PT may not be superior to CBIT alone in reducing tic severity and improving quality of life. CBIT alone showed advantages in improving quality of life over CBIT + PT and PT alone. CBIT might be an appropriate treatment option for patients with tic disorder in Chinese mainland.

16.
Front Comput Neurosci ; 16: 1047954, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36405786

RESUMO

Tic is a combination of a series of static facial and limb movements over a certain period in some children. However, due to the scarcity of tic disorder (TD) datasets, the existing work on tic recognition using deep learning does not work well. It is that spatial complexity and time-domain variability directly affect the accuracy of tic recognition. How to extract effective visual information for temporal and spatial expression and classification of tic movement is the key of tic recognition. We designed the slow-fast and light-efficient channel attention network (SFLCA-Net) to identify tic action. The whole network adopted two fast and slow branch subnetworks, and light-efficient channel attention (LCA) module, which was designed to solve the problem of insufficient complementarity of spatial-temporal channel information. The SFLCA-Net is verified on our TD dataset and the experimental results demonstrate the effectiveness of our method.

17.
Front Pediatr ; 10: 945616, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35874596

RESUMO

Background: This study aimed to identify the threshold for success in supracondylar humeral fracture surgery by describing the learning curve for beginners and exploring the relationship between the learning curve and the prognosis of supracondylar fractures of the humerus. Methods: Surgical information was collected of the first 100 humeral fractures treated by four pediatric orthopedic surgeons. The relationship between operation time, wire placement success rate, and surgical experience was determined using the restricted cubic strip (RCS). The inflection point in the curve and other risk factors that may affect fracture prognosis were collected and subjected to multiple logistic regression to clarify the relationship between the learning curve and prognosis of supracondylar fractures of the humerus. After the training, the four fresh surgeons were interviewed in the form of questionnaires to get feedback from the trainees. Results: A total of 400 supracondylar fractures of the humerus from four pediatric orthopedists were included in the study. On an RCS analysis, 65 surgical experiences were the inflection point of the learning curve. Before and after these 65 surgical experiences, there were significant differences in the patients' anatomical reduction (186 vs. 122, P < 0.001), conversion to incision (33 vs. 6, P = 0.008), and supervising physician guidance (28 vs. 2, P < 0.001). In the multiple logistic regression analysis, functional recovery after supracondylar fractures of the humerus was significantly associated with surgical experience, intraoperative conversion to incision, and post-operative infection. Four surgeons and a supervisor were interviewed. They believed that self-confidence establishment requires the experience accumulation of about 30 operations. The most critical surgical technique is the reduction of fractures. Conclusions: Although the accumulated experience of 30 operations can establish the self-confidence of trainers, fresh surgeons must accumulate experience with 65 operations to master closed reduction and internal fixation for supracondylar fractures. Surgical experience significantly impacts the post-operative recovery of patients with fractures. Level of Evidence: Level III.

18.
Small ; 18(16): e2106403, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35274455

RESUMO

Energy-storage materials can be assembled directly on the electrodes of a battery using electrochemical methods, this allowing sequential deposition, high structural control, and low cost. Here, a two-step approach combining electrophoretic deposition (EPD) and cathodic electrodeposition (CED) is demonstrated to fabricate multilayer hierarchical electrodes of reduced graphene oxide (rGO) and mixed transition metal sulfides (NiCoMnSx ). The process is performed directly on conductive electrodes applying a small electric bias to electro-deposit rGO and NiCoMnSx in alternated cycles, yielding an ideal porous network and a continuous path for transport of ions and electrons. A fully rechargeable alkaline battery (RAB) assembled with such electrodes gives maximum energy density of 97.2 Wh kg-1 and maximum power density of 3.1 kW kg-1 , calculated on the total mass of active materials, and outstanding cycling stability (retention 72% after 7000 charge/discharge cycles at 10 A g-1 ). When the total electrode mass of the cell is considered, the authors achieve an unprecedented gravimetric energy density of 68.5 Wh kg-1 , sevenfold higher than that of typical commercial supercapacitors, higher than that of Ni/Cd or lead-acid Batteries and similar to Ni-MH Batteries. The approach can be used to assemble multilayer composite structures on arbitrary electrode shapes.

19.
Artigo em Inglês | MEDLINE | ID: mdl-35329414

RESUMO

The Yangtze River economic belt is an inland river economic belt with international influence composed of 11 provinces and municipalities in the Yangtze River Basin. This paper uses the super-efficiency model to calculate the green total factor productivity of 11 provinces and municipalities in the Yangtze River economic belt (YREB). Then we establish a model to study the impact of industrial structure upgrading, industrial structure rationalization, and environmental regulation on green total factor productivity (GTFP). Empirical analysis shows that the industrial structure upgrading and environmental regulation have a significant impact on GTFP and show regional characteristics. The more developed the economy and the higher the industrial structure, the greater the impact of upgrading and environmental regulation on GTFP. Compared with other control variables, the urbanization rate impacts GTFP, followed by regional economic development.


Assuntos
Desenvolvimento Econômico , Rios , China , Cidades , Eficiência , Indústrias
20.
Nat Genet ; 54(1): 73-83, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34980919

RESUMO

Lychee is an exotic tropical fruit with a distinct flavor. The genome of cultivar 'Feizixiao' was assembled into 15 pseudochromosomes, totaling ~470 Mb. High heterozygosity (2.27%) resulted in two complete haplotypic assemblies. A total of 13,517 allelic genes (42.4%) were differentially expressed in diverse tissues. Analyses of 72 resequenced lychee accessions revealed two independent domestication events. The extremely early maturing cultivars preferentially aligned to one haplotype were domesticated from a wild population in Yunnan, whereas the late-maturing cultivars that mapped mostly to the second haplotype were domesticated independently from a wild population in Hainan. Early maturing cultivars were probably developed in Guangdong via hybridization between extremely early maturing cultivar and late-maturing cultivar individuals. Variable deletions of a 3.7 kb region encompassed by a pair of CONSTANS-like genes probably regulate fruit maturation differences among lychee cultivars. These genomic resources provide insights into the natural history of lychee domestication and will accelerate the improvement of lychee and related crops.


Assuntos
Domesticação , Genoma de Planta , Litchi/genética , China , Produtos Agrícolas/genética , Evolução Molecular , Flores/genética , Haplótipos , Heterozigoto , Litchi/crescimento & desenvolvimento , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Especificidade da Espécie
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