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1.
Sensors (Basel) ; 24(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38894345

RESUMO

In this study, an innovative laser 3D-scanning technology is proposed to scan pipe inner walls in order to solve the problems of the exorbitant expenses and operational complexities of the current equipment for the 3D data acquisition of the pipe inner wall, and the difficulty of both the efficiency and accuracy of traditional light stripe-center extraction methods. The core of this technology is the monocular-structured light 3D scanner, the image processing strategy based on tracking speckles, and the improved gray barycenter method. The experimental results demonstrate a 52% reduction in the average standard error of the improved gray barycenter method when compared to the traditional gray barycenter method, along with an 83% decrease in the operation time when compared to the Steger method. In addition, the size data of the inner wall of the pipe obtained using this technology is accurate, and the average deviation of the inner diameter and length of the pipe is less than 0.13 mm and 0.41 mm, respectively. In general, it not only reduces the cost, but also ensures high efficiency and high precision, providing a new and efficient method for the 3D data acquisition of the inner wall of the pipe.

2.
J Imaging ; 9(12)2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38132676

RESUMO

The phenotyping of plant growth enriches our understanding of intricate genetic characteristics, paving the way for advancements in modern breeding and precision agriculture. Within the domain of phenotyping, segmenting 3D point clouds of plant organs is the basis of extracting plant phenotypic parameters. In this study, we introduce a novel method for point-cloud downsampling that adeptly mitigates the challenges posed by sample imbalances. In subsequent developments, we architect a deep learning framework founded on the principles of SqueezeNet for the segmentation of plant point clouds. In addition, we also use the time series as input variables, which effectively improves the segmentation accuracy of the network. Based on semantic segmentation, the MeanShift algorithm is employed to execute instance segmentation on the point-cloud data of crops. In semantic segmentation, the average Precision, Recall, F1-score, and IoU of maize reached 99.35%, 99.26%, 99.30%, and 98.61%, and the average Precision, Recall, F1-score, and IoU of tomato reached 97.98%, 97.92%, 97.95%, and 95.98%. In instance segmentation, the accuracy of maize and tomato reached 98.45% and 96.12%. This research holds the potential to advance the fields of plant phenotypic extraction, ideotype selection, and precision agriculture.

3.
Zhongguo Zhong Yao Za Zhi ; 34(7): 858-60, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19623981

RESUMO

OBJECTIVE: To investigate the chemical constituents of the leaves of Aquilaria sinensis, and provide a certain of basis for the comprehensive uses of the plant of A. sinensis. METHOD: The chemical constituents were isolated by various column chromatographic method. The structures were identified by spectral analyses of NMR, MS, et al. RESULT: Thirteen compounds were isolated and identified as 7-hyroxy-5, 4'-dimethoxy flovone (1), 5-hydroxy-7, 4'-dimethoxy flavone (2), luteolin-7-3',4'-trimethyl (3), isocorydine (4), 4-hydroxybenzoic acid (5), triacontenoic (6), hentriacontane (7), alpha-stigmasterol (8), epifriedelanol (9), friedelan (10), friedelin (11), genkwanin (12), 5, 4'-dihyroxy-7, 3'-dimethoxy flovone (13). CONCLUSION: Compound 4 was obtained from this genus for the first time, compounds 1, 6-11, 13 were obtained from this species for the first time.


Assuntos
Folhas de Planta/química , Thymelaeaceae/química , Espectroscopia de Ressonância Magnética , Compostos Orgânicos/análise , Compostos Orgânicos/química , Compostos Orgânicos/isolamento & purificação
4.
Sci Rep ; 9(1): 5226, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30914701

RESUMO

Soil oxygen shortages in root areas have negative effects on crop growth and decrease crops yield and quality, and soil hypoxia conditions will be aggravated by application of subsurface drip irrigation (SDI). A two-year field experiment was conducted to evaluate the response of maize to micro/nanobubbles oxygation (MNBO) at three dissolved oxygen (DO) concentrations (10, 20 and 30 mg/L) and seven MNBO periods (vegetative stage, reproductive stage, filling and ripening stage, combination of two stages and the whole growth stage) in addition to a control treatment (CK, no oxygation during the growth period). Our results revealed that the MNBO treatments increased maize root dry weight, root length density and root surface area in 0-20 cm soil. The highest yield was obtained in O20A (MNBO at 20 mg/L DO during the growth period), with an increase of 11.66% relative to CK. Crude ash, starch and vitamin C were improved by application of MNBO at 20 mg/L DO. However, excessive oxygen adversely affected maize growth, decreasing the maize yield in 2013 relative to CK. The results suggest that application of MNBO at 20 mg/L DO during the growth period of spring maize was appropriate.


Assuntos
Oxigênio/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Solo
5.
RSC Adv ; 9(36): 20742-20748, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35515517

RESUMO

Highly efficient red-emitting Eu3+-doped double perovskite Ca2YSbO6 phosphors have been successfully prepared by the traditional high-temperature solid state method. The phase purity, photoluminescence and decay properties as a function of the Eu3+ concentration have been investigated in detail. The XRD results demonstrate that all of the obtained phosphors can be assigned to a pure monoclinic structure. Upon 464 nm excitation, a strong red emission situated at 614 nm (5D0-7F2) indicates that Eu3+ ions occupy a site with low symmetry. The quenching concentration of Eu3+ ions reaches as high as 70 mol% and the quenching mechanism is discussed. Especially, the prepared phosphor exhibits a high quantum efficiency of 92.1% and superior thermal stability, with PL intensity at 423 K up to 81.6% of that at room temperature. Moreover, a warm white light with a correlated color temperature of 4720 K and a color rendering index of 82.6 is achieved by fabricating a Ca2YSbO6:Eu3+ phosphor in a 460 nm blue-InGaN chip together with the commercial Y3Al5O12:Ce3+ yellow phosphor.

6.
Dalton Trans ; 47(18): 6528-6537, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29696276

RESUMO

Owing to its low-cost and satisfactory luminescent-emission performance in warm white light-emitting diodes (w-LEDs), the non-rare-earth Mn4+-activated red phosphor has become a promising competitor of commercial rare-earth doped phosphor. In this study, a series of novel red-light emitting phosphors based on Ca2YSbO6:Mn4+ have been developed successfully by a conventional solid-state reaction. The structural and luminescent properties of these phosphors are systematically investigated. The as-prepared Ca2YSbO6:Mn4+ product exhibits a broad excitation band ranging from 250 to 600 nm and an abnormal intense deep-red emission centered at 680 nm with a full width at half maximum (FWHM) of ∼46 nm. The optimal Mn4+ doping concentration is about 0.3 mol%, and the concentration quenching mechanism is determined to be a dipole-dipole interaction. Impressively, the Ca2YSbO6:0.003Mn4+ phosphor shows an outstanding quantum efficiency of 62.6% and an excellent thermal stability. In addition, the effect of Li+, Mg2+, Na+ and K+ dopants on the luminescent properties of Mn4+-doped Ca2YSbO6 phosphors is elucidated. Furthermore, by employing the as-prepared Ca2YSbO6:Mn4+ as a red component, a warm w-LED with high color rendering index (Ra = 87.5) and low correlated color temperature (CCT = 3255 K) can be acquired. It is believed that the present phosphor has a potential application as a supplement of the red component for warm w-LEDs.

7.
Chin J Nat Med ; 13(4): 290-4, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25908626

RESUMO

The present study was designed to determine the chemical constituents and identify new components of the leaves of Aquilaria sinensis (Lour.) Gilg. The compounds were isolated and purified by repeated silica gel, Sephadex LH-20, and ODS column chromatography and their structures were elucidated by NMR and HR-ESI-MS spectrometry. Eight megastigmane glycosides and two cucurbitacins were isolated and identified as (9S) megastigma-4,7-diene-2,3,9-triol 9-O-ß-D-glucopyranoside (1), (9S) megastigma-4(13),7-diene-3,6,9-triol 9-O-ß-D-glucopyranoside (2), macarangloside D (3), corchoionoside C (4), staphylionoside H (5), (+) 3-oxo-α-ionol-ß-D-glucopyranoside (6), (-) 3-oxo-α-ionol-ß-D-glucopyranoside (7), citroside B (8), 2-O-ß-D-glucopyranosyl cucurbitacin I (9), bryoamaride (10). Compounds 1 and 2 were newly identified megstigmane glucosides and reported from this genus for the first time.


Assuntos
Cicloexanonas/química , Glucosídeos/química , Norisoprenoides/química , Folhas de Planta/química , Thymelaeaceae/química , Cromatografia Líquida , Cucurbitacinas/química , Glucosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Norisoprenoides/isolamento & purificação
8.
Drug Des Devel Ther ; 7: 767-70, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23976844

RESUMO

A 41-year-old male had suffered from gradual hearing loss in his right ear for 2 years. Head computed tomography and magnetic resonance imaging scans showed a neoplasm in the cerebellopontine angle region, which was confirmed by the diagnosis of acoustic neurilemmoma by pathological findings after surgery. Following surgery, he routinely received valproic acid (VPA) to prevent seizures. However, the patient presented with hypofibrinogenemia and cerebral hemorrhage after taking VPA for 12 days. The hypofibrinogenemia recurred when VPA was re-administered. After withdrawal of VPA, his fibrinogen concentration rose to normal within several days. As far as we are aware, this is the first case of cerebral hemorrhage due to VPA to have been reported. Herein, as well as reporting on this case, a mini review of the relevant literature is also presented.


Assuntos
Afibrinogenemia/induzido quimicamente , Anticonvulsivantes/efeitos adversos , Hemorragia Cerebral/induzido quimicamente , Ácido Valproico/efeitos adversos , Adulto , Anticonvulsivantes/uso terapêutico , Humanos , Masculino , Convulsões/prevenção & controle , Fatores de Tempo , Ácido Valproico/uso terapêutico
9.
Asian Pac J Cancer Prev ; 13(9): 4777-81, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23167419

RESUMO

OBJECTIVE: To investigate the relationship between the efficacy and safety of different doses of thalidomide (Thal) plus dexamethasone (Dex) as the initial therapy in elderly patients with newly diagnosed multiple myeloma (MM). METHODS: Clinical data of 28 elderly patients with newly diagnosed MM who underwent the TD regimen as the initial therapy were analyzed retrospectively. The patients were divided into two groups according to the maximal sustained dose of Thal: lower dose (group A) and higher dose (group B). The overall response rate (ORR), progression free survival (PFS), overall survival (OS), and adverse events (AES) were compared between the two groups. RESULTS: A total of 28 patients were followed up with a median of 18 months. The ORR was 60.1%. The median response time and PFS were 2.0 and 17.0 months, respectively. The mean sustained dose of Thal in group B was significantly higher than group A (292.9 mg v 180.4 mg, P=0.01). There was no significantly difference in ORR (57.1% v 64.3%, P=1.00) and PFS (9.63months v 17.66 months, P=0.73) between groups A and B. During the follow up, only five patients died (<40%) and, therefore, median OS values were not available. It is estimated, however, that the mean survival time in the two groups was 35.6 and 33.4 months (P>0.05), respectively. All of the patients tolerated the treatment well. The incidence of AES in patients with a grading above 3 in group B was significantly higher than in group A (P=0.033). CONCLUSIONS: The TD regimen results in a high response rate and manageable AES as the initial therapy in elderly patients with MM. TD should be considered as the front line regimen for the treatment of elderly patients with MM in areas with financial constraints. The clinical response can be achieved at a low dose Thal with minimal toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Dexametasona/administração & dosagem , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Talidomida/administração & dosagem , Resultado do Tratamento
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