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1.
Small ; 20(40): e2402774, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38805741

RESUMO

2D layered molybdenum disulfide (MoS2) has garnered considerable attention as an attractive electrode material in sodium-ion batteries (SIBs), but sluggish mass transfer kinetic and capacity fading make it suffer from inferior cycle capability. Herein, hierarchical MoS2 nanosheets decorated porous TiO2 nanofibers (MoS2 NSs@TiO2 NFs) with rich oxygen vacancies are engineered by microemulsion electrospinning method and subsequent hydrothermal/heat treatment. The MoS2 NSs@TiO2 NFs improves ion/electron transport kinetic and long-term cycling performance through distinctive porous structure and heterogeneous component. Consequently, the electrode exhibits excellent long-term Na storage capacity (298.4 mAh g-1 at 5 A g-1 over 1100 cycles and 235.6 mAh g-1 at 10 A g-1 over 7200 cycles). Employing Na3V2(PO4)3 as cathode, the full cell maintains a desirable capacity of 269.6 mAh g-1 over 700 cycles at 1.0 A g-1. The stepwise intercalation-conversion and insertion/extraction endows outstanding Na+ storage performance, which yields valuable insight into the advancement of fast-charging and long-cycle life SIBs anode materials.

2.
Inorg Chem ; 63(26): 12377-12384, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38902911

RESUMO

Pathogenic bacteria have consistently posed a formidable challenge to human health, creating the critical need for effective antibacterial solutions. In response, enzyme-metal-organic framework (MOF) composites have emerged as a promising class of antibacterial agents. This study focuses on the development of an enzyme-MOF composite based on HZIF-8, incorporating the advantages of simple synthesis, ZIF-8 antibacterial properties, lysozyme hydrolysis, and high biological safety. Through a one-pot method, core-shell nanoparticles (HZIF-8) were synthesized. This structure enables efficient immobilization of lysozyme and lactoferrin within the HZIF-8, resulting in the formation of the lysozyme-lactoferrin@HZIF-8 (LYZ-LF@HZIF-8) composite. Upon exposure to light irradiation, HZIF-8 itself possessed antibacterial properties. Lysozyme initiated the degradation of bacterial peptidoglycan and lactoferrin synergistically enhanced the antibacterial effect of lysozyme. All of the above ultimately contributed to comprehensive antibacterial activity. Antibacterial assessments demonstrated the efficacy of the LYZ-LF@HZIF-8 composite, effectively eradicating Staphylococcus aureus at a cell density of 1.5 × 106 CFU/mL with a low dosage of 200 µg/mL and completely inactivating Escherichia coli at 400 µg/mL with the same cell density. The enzyme-MOF composite exhibited significant and durable antibacterial efficacy, with no apparent cytotoxicity in vitro, thereby unveiling expansive prospects for applications in the medical and food industries.


Assuntos
Antibacterianos , Escherichia coli , Lactoferrina , Estruturas Metalorgânicas , Testes de Sensibilidade Microbiana , Muramidase , Staphylococcus aureus , Zeolitas , Muramidase/farmacologia , Muramidase/química , Muramidase/metabolismo , Lactoferrina/química , Lactoferrina/farmacologia , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Estruturas Metalorgânicas/síntese química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Zeolitas/química , Zeolitas/farmacologia , Imidazóis/química , Imidazóis/farmacologia , Imidazóis/síntese química , Porosidade , Propriedades de Superfície , Tamanho da Partícula , Enzimas Imobilizadas/química , Enzimas Imobilizadas/farmacologia
3.
Ecotoxicol Environ Saf ; 276: 116317, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615641

RESUMO

We have previously shown that excessive activation of macrophage proinflammatory activity plays a key role in TCE-induced immune liver injury, but the mechanism of polarization is unclear. Recent studies have shown that TLR9 activation plays an important regulatory role in macrophage polarization. In the present study, we demonstrated that elevated levels of oxidative stress in hepatocytes mediate the release of mtDNA into the bloodstream, leading to the activation of TLR9 in macrophages to regulate macrophage polarization. In vivo experiments revealed that pretreatment with SS-31, a mitochondria-targeting antioxidant peptide, reduced the level of oxidative stress in hepatocytes, leading to a decrease in mtDNA release. Importantly, SS-31 pretreatment inhibited TLR9 activation in macrophages, suggesting that hepatocyte mtDNA may activate TLR9 in macrophages. Further studies revealed that pharmacological inhibition of TLR9 by ODN2088 partially blocked macrophage activation, suggesting that the level of macrophage activation is dependent on TLR9 activation. In vitro experiments involving the extraction of mtDNA from TCE-sensitized mice treated with RAW264.7 cells further confirmed that hepatocyte mtDNA can activate TLR9 in mouse peritoneal macrophages, leading to macrophage polarization. In summary, our study comprehensively confirmed that TLR9 activation in macrophages is dependent on mtDNA released by elevated levels of oxidative stress in hepatocytes and that TLR9 activation in macrophages plays a key role in regulating macrophage polarization. These findings reveal the mechanism of macrophage activation in TCE-induced immune liver injury and provide new perspectives and therapeutic targets for the treatment of OMDT-induced immune liver injury.


Assuntos
DNA Mitocondrial , Hepatócitos , Estresse Oxidativo , Receptor Toll-Like 9 , Tricloroetileno , Animais , Camundongos , Hepatócitos/efeitos dos fármacos , Tricloroetileno/toxicidade , Receptor Toll-Like 9/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Células RAW 264.7 , Doença Hepática Induzida por Substâncias e Drogas , Ativação de Macrófagos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL
4.
Artigo em Inglês | MEDLINE | ID: mdl-38726473

RESUMO

BACKGROUND: Cleft lip and palate is one of the most common oral and maxillofacial deformities associated with a variety of functional disorders. Cleft palate speech disorder (CPSD) occurs the most frequently and manifests a series of characteristic speech features, which are called cleft speech characteristics. Some scholars believe that children with CPSD and poor speech outcomes may also have weaknesses in speech input processing ability, but evidence is still lacking so far. AIMS: (1) To explore whether children with CPSD and speech output disorders also have defects in speech input processing abilities; (2) to explore the correlation between speech input and output processing abilities. METHODS & PROCEDURES: Children in the experimental group were enrolled from Beijing Stomatological Hospital, Capital Medical University, and healthy volunteers were recruited as controls. Then three tasks containing real and pseudo words were performed sequentially. Reaction time, accuracy and other indicators in three tasks were collected and then analysed. OUTCOMES & RESULTS: The indicators in the experimental group were significantly lower than those in the control group. There was a strong correlation between speech input and output processing tasks. The performance of both groups when processing pseudo words in the three tasks was worse than that when dealing with real words. CONCLUSIONS & IMPLICATIONS: Compared with normal controls, children with CPSD have deficits in both speech input and output processing, and there is a strong correlation between speech input and output speech processing abilities. In addition, the pseudo words task was more challenging than the real word task for both groups. WHAT THIS PAPER ADDS: What is already known on the subject Children with cleft lip and palate often have speech sound disorders known as cleft palate speech disorder (CPSD). CPSD is characterised by consonant errors called cleft speech characteristics, which can persist even after surgery. Some studies suggest that poor speech outcomes in children with CPSD may be associated with deficits in processing speech input. However, this has not been validated in mainland China. What this paper adds to existing knowledge The results of our study indicate that children with CPSD exhibit poorer performance in three tasks assessing speech input and output abilities compared to healthy controls, suggesting their deficits in both speech input and output processing. Furthermore, a significant correlation was observed between speech input and output processing abilities. Additionally, both groups demonstrated greater difficulty in processing pseudo words compared to real words, as evidenced by their worse performance in dealing with pseudo words. What are the potential or actual clinical implications of this work? The pseudo word tasks designed and implemented in our study can be employed in future research and assessment of speech input and output abilities in Chinese Mandarin children with CPSD. Additionally, our findings revealed the significance of considering both speech output processing abilities and potential existence of speech input processing ability for speech and language therapists when evaluating and developing treatment options for children with CPSD as these abilities are also important for the development of literacy development.

5.
Aesthetic Plast Surg ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789807

RESUMO

BACKGROUND: Androgenetic alopecia (AGA) is a prevalent type of hair loss that impacts individuals of both genders. Platelet-rich plasma (PRP) and minoxidil have been employed as therapeutic interventions for AGA, yet the efficacy of their concurrent use remains ambiguous. OBJECTIVE: To perform a comprehensive review and meta-analysis aimed at evaluating the effectiveness of platelet-rich plasma (PRP) in combination with minoxidil for the treatment of androgenetic alopecia (AGA). METHODS: We conducted a comprehensive search of the databases PubMed, Embase, Web of Science, and Cochrane Library, encompassing their complete records up until December 2023. Eligible studies were randomized controlled trials that compared the combination of PRP and minoxidil with minoxidil or PRP alone in patients with AGA. The primary outcome measure was the change in hair growth as assessed by the hair density or hair thickness. Secondary outcome measures included patient satisfaction, and global photographic assessment. RESULTS: A total of 6 studies involving 343 participants were included in this meta-analysis. The results showed that PRP combined with minoxidil significantly improved hair growth compared to minoxidil or PRP alone. The pooled analysis demonstrated a significant increase in hair density (weighted mean difference [WMD] = 9.14; 95% confidence interval [CI]: 6.57-11.70) and hair diameter (WMD = 4.72; 95% CI 3.21-6.23) in the PRP combined with minoxidil group. Moreover, patients receiving PRP combined with minoxidil reported higher satisfaction rates compared to those using minoxidil or PRP alone. CONCLUSIONS: This meta-analysis suggests that PRP combined with minoxidil is an effective treatment for AGA, providing significant improvement in hair growth and patient satisfaction. LEVEL OF EVIDENCE III: 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 .

6.
J Environ Manage ; 351: 119890, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38160542

RESUMO

The high-concentration powder carrier bio-fluidized bed (HPB) technology is an emerging approach that enables on-site upgrading of wastewater treatment plants (WWTPs). HPB technology promotes the formation of biofilm sludge with micron-scale composite powder carriers as the core and suspended sludge mainly composed of flocs surrounding the biofilm sludge. This study proposed a novel integrated strategy for assessing and controlling the sludge ages in suspended/bio-film activated sludge supported by micron-scale composite powder carrier. Utilizing the cyclone unit and the corresponding theoretical model, the proposed strategy effectively addresses the sludge ages contradiction between denitrifying bacteria and polyphosphate-accumulating organisms (PAOs), thereby enhancing the efficiency of municipal wastewater treatment. The sludge age of the suspended (25 d) and bio-film (99 d) sludge, calculated using the model, contribute to the simultaneous removal of nitrogen and phosphorus. Meanwhile, the model further estimates distinct contributions of suspended and bio-film sludge to chemical oxygen demand (COD) and total nitrogen (TN), which are 55% and 42% for COD, 20% and 57% for TN of suspended sludge and bio-film sludge, respectively. This suggests that the contribution of suspended sludge and bio-film sludge to COD and TN removal efficiency can be determined and controlled by the operational conditions of the cyclone unit. Additionally, the simulation values for COD, ammonia nitrogen (NH4+-N), TN and total phosphorus (TP) closely align with the actual values of WWTPs over 70 days (p < 0.001) with the correlation coefficients (R2) of 0.9809, 0.9932, 0.9825, and 0.837, respectively. These results support the theoretical foundation of HPB technology for simultaneous nitrogen and phosphorus removal in sewage treatment plants. Therefore, this model serves as a valuable tool to guide the operation, design, and carrier addition in HPB technology implementation.


Assuntos
Esgotos , Purificação da Água , Esgotos/química , Águas Residuárias , Pós , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos/microbiologia , Fósforo , Nitrogênio , Desnitrificação
7.
Chin Med Sci J ; 39(1): 19-28, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38623048

RESUMO

Objective As primary Sj?gren's syndrome (pSS) primarily affects the salivary glands, saliva can serve as an indicator of the glands' pathophysiology and the disease's status. This study aims to illustrate the salivary proteomic profiles of pSS patients and identify potential candidate biomarkers for diagnosis.Methods The discovery set contained 49 samples (24 from pSS and 25 from age- and gender-matched healthy controls [HCs]) and the validation set included 25 samples (12 from pSS and 13 from HCs). Totally 36 pSS patients and 38 HCs were centrally randomized into the discovery set or to the validation set at a 2:1 ratio. Unstimulated whole saliva samples from pSS patients and HCs were analyzed using a data-independent acquisition (DIA) strategy on a 2D LC?HRMS/MS platform to reveal differential proteins. The crucial proteins were verified using DIA analysis and annotated using gene ontology (GO) and International Pharmaceutical Abstracts (IPA) analysis. A prediction model for SS was established using random forests.Results A total of 1,963 proteins were discovered, and 136 proteins exhibited differential representation in pSS patients. The bioinformatic research indicated that these proteins were primarily linked to immunological functions, metabolism, and inflammation. A panel of 19 protein biomarkers was identified by ranking order based on P-value and random forest algorichm, and was validated as the predictive biomarkers exhibiting good performance with area under the curve (AUC) of 0.817 for discovery set and 0.882 for validation set.Conclusions The candidate protein panel discovered may aid in pSS diagnosis. Salivary proteomic analysis is a promising non-invasive method for prognostic evaluation and early and precise treatments for pSS patients. DIA offers the best time efficiency and data dependability and may be a suitable option for future research on the salivary proteome.


Assuntos
Síndrome de Sjogren , Humanos , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/metabolismo , Proteômica/métodos , Biomarcadores/metabolismo , Saliva/metabolismo , Prognóstico
8.
Zhongguo Zhong Yao Za Zhi ; 49(4): 968-980, 2024 Feb.
Artigo em Zh | MEDLINE | ID: mdl-38621904

RESUMO

This study aims to characterize and identify the chemical constituents in 11 parts of Forsythia suspensa by using ultra-performance liquid chromatography-quadrupole time of flight-mass spectrometry(UPLC-Q-TOF-MS) combined with a self-established chemical constituent database, including leaves, flowers, fruits, green F. suspensa, old F. suspensa, and seeds. The quality attributes and differences of different parts of F. suspensa were evaluated by principal component analysis, partial least square discriminant analysis, and other stoichiometric methods. A total of 79 compounds were identified, including 13 phenylethanol glycosides, 10 lignans, 12 flavonoids, 10 organic acids, 14 terpenoids, and 20 other types of compounds. Among them, 34 compounds were the main variables of difference between the different parts of F. suspensa, and the content of each component was relatively higher in the leaves and green F. suspensa. The LPS-induced inflammation model of RAW264.7 cells was applied to study the anti-inflammatory activity of the extracts of the different parts of F. suspensa and the main constituents. The results show that the extracts of green F. suspensa, flower, twig, and stem exhibited anti-inflammatory activity, and the constituents such as forsythoside A, phyllyrin, phillygenin, and(+)-pinoresinol-ß-D-glucopyranoside could significantly inhibit anti-inflammatory activity released by NO. The chemical constituent in different parts of F. suspensa is analyzed comprehensively, and the anti-inflammatory activity is evaluated in this study, which provides a reference for the development and comprehensive utilization of F. suspensa resources.


Assuntos
Forsythia , Extratos Vegetais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Forsythia/química , Cromatografia Líquida de Alta Pressão , Flavonoides , Anti-Inflamatórios/farmacologia
9.
Phys Chem Chem Phys ; 25(36): 24733-24744, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37670665

RESUMO

The catalytic conversion of carbon dioxide (CO2) and olefins into acrylates has been a long standing target, because society attempts to synthesize commodity chemicals in a more economical and sustainable fashion. In this work, two alkylation reaction pathways were investigated to explore the role of methylene linkage (-CH2-) on the formation of alkyl acrylate from coupling of CO2 and ethylene, catalyzed by a nickel catalyst in the presence of different alkyl iodides. The energy barrier of Ni-O bond cleavage decreases with increasing methylene linkage of alkyl iodides, which may be due to NPA charge transfer of alkyl iodides. Meanwhile, the O1 (ester sp3 O atom) attack route leading to the formation of alkyl acrylate competes with the O2 (carboxylic sp2 O atom) attack route in terms of energy barriers. Further studies on the fluoro-substituted alkyl acrylates show that neither CF3I nor CF3CH2I is effective in releasing trifluoroalkyl acrylates from the nickellacycle, which explains why only negligible amounts of the desired product were detected in the experiment. In addition, we investigated the non-productive pathways leading to byproducts, such as propionic acid, propionates and ion pair complexes, etc. By comparing the results obtained with CH3I, the use of C2H5I as an electrophilic reagent may stabilize the non-productive intermediates. The methylene linkage has little effect on the main productive pathway. However, it has a significant influence on the side reactions, which is detrimental to the formation of alkyl acrylate in competing with the main productive pathway.

10.
Sensors (Basel) ; 23(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37177776

RESUMO

The leaf phenotypic traits of plants have a significant impact on the efficiency of canopy photosynthesis. However, traditional methods such as destructive sampling will hinder the continuous monitoring of plant growth, while manual measurements in the field are both time-consuming and laborious. Nondestructive and accurate measurements of leaf phenotypic parameters can be achieved through the use of 3D canopy models and object segmentation techniques. This paper proposed an automatic branch-leaf segmentation pipeline based on lidar point cloud and conducted the automatic measurement of leaf inclination angle, length, width, and area, using pear canopy as an example. Firstly, a three-dimensional model using a lidar point cloud was established using SCENE software. Next, 305 pear tree branches were manually divided into branch points and leaf points, and 45 branch samples were selected as test data. Leaf points were further marked as 572 leaf instances on these test data. The PointNet++ model was used, with 260 point clouds as training input to carry out semantic segmentation of branches and leaves. Using the leaf point clouds in the test dataset as input, a single leaf instance was extracted by means of a mean shift clustering algorithm. Finally, based on the single leaf point cloud, the leaf inclination angle was calculated by plane fitting, while the leaf length, width, and area were calculated by midrib fitting and triangulation. The semantic segmentation model was tested on 45 branches, with a mean Precisionsem, mean Recallsem, mean F1-score, and mean Intersection over Union (IoU) of branches and leaves of 0.93, 0.94, 0.93, and 0.88, respectively. For single leaf extraction, the Precisionins, Recallins, and mean coverage (mCoV) were 0.89, 0.92, and 0.87, respectively. Using the proposed method, the estimated leaf inclination, length, width, and area of pear leaves showed a high correlation with manual measurements, with correlation coefficients of 0.94 (root mean squared error: 4.44°), 0.94 (root mean squared error: 0.43 cm), 0.91 (root mean squared error: 0.39 cm), and 0.93 (root mean squared error: 5.21 cm2), respectively. These results demonstrate that the method can automatically and accurately measure the phenotypic parameters of pear leaves. This has great significance for monitoring pear tree growth, simulating canopy photosynthesis, and optimizing orchard management.


Assuntos
Imageamento Tridimensional , Pyrus , Imageamento Tridimensional/métodos , Árvores , Plantas , Folhas de Planta
11.
Opt Lett ; 47(23): 6221-6224, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219214

RESUMO

We show that stable (3+1)-dimensional vector light bullets with ultraslow propagating velocity and extreme low generation power can be realized in a cold Rydberg atomic gas. They can also be actively controlled by using a nonuniform magnetic field; especially, trajectories of their two polarization components can have significant Stern-Gerlach deflections. The results obtained are useful for revealing the nonlocal nonlinear optical property of Rydberg media and for measuring weak magnetic fields.

12.
Phys Chem Chem Phys ; 24(35): 21078-21084, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36017736

RESUMO

Extensive global minimum searches augmented with first-principles theory calculations performed in this work indicate that the experimentally observed perfect inverse sandwich lanthanide boride complexes D7h La2B7- (1), D8h La2B8 (3), D9h La2B9- (7) can be extended to their actinide counterparts C2v Ac2B7- (1'), D8h Ac2B8 (3'), D9h Ac2B9- (7') with a Bn monocyclic ring (n = 7-9) sandwiched by two Ac dopants. Such M2Bn-/0 inverse sandwiches (1/1', 3/3', 7/7') can be used as building blocks to generate the ground-state C2 La4B13- (2)/Ac4B13- (2'), D2 La4B15- (4)/Ac4B15- (4'), C3v/C3 La4B18 (5)/Ac4B18 (5'), Oh Ac7B24+ (6'), Oh Ac7B24, Td Ac4B24 (8'), C1 La5B24+ (9)/Ac5B24+ (9'), and Td Ac4B29- (10') which are based on boron frameworks consisting of multiple conjoined Bn rings (n = 7-9). Detailed bonding analyses show that effective (d-p)σ, (d-p)π and (d-p)δ coordination bonds are formed between the Bn rings and metal doping centers, conferring three-dimensional aromaticity and extra stability to the systems. In particular, the perfect body-centered cubic Oh Ac7B24+ (6') and Oh Ac7B24 with six conjoined B8 rings can be extended in x, y, and z dimensions to form one-dimensional Ac10B32 (11'), two-dimensional Ac3B10 (12'), and three-dimensional AcB6 (13') nanomaterials, presenting a B8-based bottom-up approach from metal boride nanoclusters to their low-dimensional nanomaterials.

13.
Phys Chem Chem Phys ; 24(6): 3918-3923, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35094042

RESUMO

It is well-known that transition-metal-doping induces dramatic changes in the structures and bonding of small boron clusters, as demonstrated by the newly observed perfect inverse sandwich D8h [La(η8-B8)La] and D9h [La(η9-B9)La]-. Based on extensive global minimum searches and first-principles theory calculations, we predict herein the possibility of perfect endohedral trihedral metallo-borospherene D3h La@[La5&B30] (1, 3A'1) and its monoanion Cs La@[La5&B30]- (2, 2A') and dianion D3h La@[La5&B30]2- (3, 1A'1). These La-doped boron clusters are composed of three inverse sandwich La(η8-B8)La on the waist and two inverse sandwich La(η9-B9)La on the top and bottom which share one apex La atom at the center and six periphery B2 units between neighboring η8-B8 and η9-B9 rings, with three octo-coordinate La atoms and two nona-coordinate La atoms as integrated parts of the cage surface. Detailed adaptive natural density partitioning (AdNDP) and iso-chemical shielding surface (ICSS) analyses indicate that La@[La5&B30]0/-/2- (1/2/3) are spherically aromatic in nature. The one-dimensional nanowire La4B21 (4, P31m) constructed from D3h La@[La5&B30] (1) along the C3 axis of the system appears to be metallic. The IR and Raman spectra of La@[La5&B30] (1) and photoelectron spectroscopy of the slightly distorted Cs La@[La5&B30]- (2) are theoretically simulated to facilitate their spectroscopic characterizations.

14.
Sensors (Basel) ; 20(10)2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32466108

RESUMO

Automatic detection of intact tomatoes on plants is highly expected for low-cost and optimal management in tomato farming. Mature tomato detection has been wildly studied, while immature tomato detection, especially when occluded with leaves, is difficult to perform using traditional image analysis, which is more important for long-term yield prediction. Therefore, tomato detection that can generalize well in real tomato cultivation scenes and is robust to issues such as fruit occlusion and variable lighting conditions is highly desired. In this study, we build a tomato detection model to automatically detect intact green tomatoes regardless of occlusions or fruit growth stage using deep learning approaches. The tomato detection model used faster region-based convolutional neural network (R-CNN) with Resnet-101 and transfer learned from the Common Objects in Context (COCO) dataset. The detection on test dataset achieved high average precision of 87.83% (intersection over union ≥ 0.5) and showed a high accuracy of tomato counting (R2 = 0.87). In addition, all the detected boxes were merged into one image to compile the tomato location map and estimate their size along one row in the greenhouse. By tomato detection, counting, location and size estimation, this method shows great potential for ripeness and yield prediction.


Assuntos
Aprendizado Profundo , Solanum lycopersicum , Frutas , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação
15.
J Comput Chem ; 40(11): 1227-1232, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30776133

RESUMO

Detailed molecular orbital and bonding analyses reveal the existence of both fluxional σ- and π-bonds in the global minima Cs B 18 2 - (1) and Cs MB18 (3) and transition states Cs B 18 2 - (2) and Cs MB 18 - (4) of B 18 2 - dianion and MB 18 - monoanions (M = K, Rb, and Cs). It is the fluxional bonds that facilitate the fluxional behaviors of the quasi-planar B 18 2 - and half-sandwich MB 18 - which possess energy barriers smaller than the difference of the corresponding zero-point corrections. © 2019 Wiley Periodicals, Inc.

16.
J Comput Chem ; 40(9): 966-970, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30341943

RESUMO

Based on detailed bonding analyses on the fluxional behaviors of planar B19 - , tubular Ta@B20 - , and cage-like B39 - , we propose the concept of fluxional bonds in boron nanoclusters as an extension of the classical localized bonds and delocalized bonds in chemistry. © 2018 Wiley Periodicals, Inc.

17.
Phys Chem Chem Phys ; 21(40): 22611-22617, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31589225

RESUMO

As the first all-boron fullerene observed in experiments, cage-like borospherene B40 has attracted considerable attention in recent years. However, B40 has been proved to be chemically reactive and tends to coalesce with one another via the formation of covalent bonds. We explore herein the possibility of low-dimensional functional networks of B40 with effective transition-metal intercalations. We find that the four equivalent B7 heptagons on the waist of each B40 can serve as effective ligands to coordinate various transition metal centers in exohedral motifs. The intercalated metal atoms entail these networks with a variety of intriguing properties. The two-dimensional (2D) Cr2B40 network is a ferromagnetic metal while the 2D Zn2B40 network becomes semiconducting. In contrast, other 2D M2B40 (M = Sc, Ti, V, Mn, Fe, Co, Ni and Cu) networks and 1D CrB40 belong to nonmagnetic metals. The 3D Cr3B40 network is a magnetic metal. This work presents the viable possibility of assembling Mn&B40 metalloborospherenes into stable functional nanomaterials via effective transition-metal intercalations with potential applications in electronic and spintronic devices.

18.
Phys Chem Chem Phys ; 20(22): 15344-15349, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29796458

RESUMO

Shortly after the discovery of all-boron fullerenes D2d B40-/0 (borospherenes), the first axially chiral borospherenes C3/C2 B39- were characterized in experiments in 2015. Based on extensive global minimum searches and first-principles theory calculations, we present herein two new axially chiral members to the borospherene family: the aromatic cage-like C2 B34(1) and C2 B35+(2). Both B34(1) and B35+(2) feature one B21 boron triple chain on the waist and two equivalent heptagons and hexagons on the cage surface, with the latter being obtained by the addition of B+ into the former at the tetracoordinate defect site. Detailed bonding analyses show that they follow the universal bonding pattern of σ + π double delocalization, with 11 delocalized π bonds over a σ skeleton. Extensive molecular dynamics simulations show that these borospherenes are kinetically stable below 1000 K and start to fluctuate at 1200 K and 1100 K, respectively. The IR, Raman, and UV-vis spectra of 1 and 2 are computationally simulated to facilitate their experimental characterization.

19.
Phys Chem Chem Phys ; 20(22): 15330-15334, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29796470

RESUMO

Recent joint experimental and theoretical investigations have shown that seashell-like C2 B28 is the smallest neutral borospherene reported to date, while seashell-like Cs B29- (1-) as a minor isomer competes with its quasi-planar counterparts in B29- cluster beams. Extensive global minimum searches and first-principles theory calculations performed in this work indicate that with two valence electrons detached from B29-, the B29+ monocation favors a seashell-like Cs B29+ (1+) much different from Cs B29- (1-) in geometry which is overwhelmingly the global minimum of the system with three B7 heptagonal holes in the front, on the back, and at the bottom, respectively, unveiling an interesting charge-induced structural transition from Cs B29- (1-) to Cs B29+ (1+). Detailed bonding analyses show that with one less σ bond than B29- (1-), Cs B29+ (1+) also possesses nine delocalized π-bonds over its σ-skeleton on the cage surface with a σ + π double delocalization bonding pattern and follows the 2(n + 1)2 electron counting rule for 3D spherical aromaticity (n = 2). B29+ (1+) is therefore the smallest borospherene monocation reported to date which is π-isovalent with the smallest neutral borospherene C2 B28. The IR, Raman, and UV-vis spectra of B29+ (1+) are computationally simulated to facilitate its spectroscopic characterization.

20.
Phys Chem Chem Phys ; 20(38): 25009-25015, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30246197

RESUMO

Transition-metal doping leads to dramatic structural changes and results in novel bonding patterns in small boron clusters. Based on the experimentally derived mono-ring planar C9v Ta©B92- (1) and extensive first-principles theory calculations, we present herein the possibility of high-symmetry double-ring tubular D9d Ta@B183- (2) and C9v Ta2@B18 (3) and triple-ring tubular D9h Ta2@B27+ (4), which may serve as embryos of single-walled metalloboronanotube α-Ta3@B48(3,0) (5) wrapped up from the recently observed most stable free-standing boron α-sheet on a Ag(111) substrate with a transition-metal wire (-Ta-Ta-) coordinated inside. Detailed bonding analyses indicate that, with an effective dz2-dz2 overlap on the Ta-Ta dimer along the C9 molecular axis, both Ta2@B18 (3) and Ta2@B27+ (4) follow the universal bonding pattern of σ + π double delocalization with each Ta center conforming to the 18-electron rule, providing tubular aromaticity to these Ta-doped boron complexes with magnetically induced ring currents. The IR, Raman, and UV-vis spectra of 3 and 4 are computationally simulated to facilitate their future experimental characterization.

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